Female adults of the migratory locust,Locusta migratoria manilensis(Meyen),can sense seasonal photoperiod changes,which induces embryonic diapause as a key strategy to overwinter.Serine protease inhibitor genes(SPNs)w...Female adults of the migratory locust,Locusta migratoria manilensis(Meyen),can sense seasonal photoperiod changes,which induces embryonic diapause as a key strategy to overwinter.Serine protease inhibitor genes(SPNs)were thought to play key roles during diapause,while few SPNs were functionally characterized.LmSPN2 was one of those genes differentially expressed between diapause and non-diapause eggs;however,its biological function remained to be explored.So,we conducted RNAi knockdown of LmSPN2,resulting in a significant decrease of the egg diapause rate by 29.7%.Using yeast two-hybrid assays,co-immunoprecipitation,and pull-down methods,we found an interaction between LmSPN2 and LmSPN3,which was proved to be mediated by a glutamate(E331)binding site of LmSPN2.RNAi knockdown of LmSPN3 resulted in a significant increase in diapause rate by 14.6%,indicating an inverse function of LmSPN2 and LmSPN3 on diapause regulation.Double knockdown of two SPN genes resulted in a 26.4%reduction in diapause rate,indicating that LmSPN2 was the dominant regulatory signal.Moreover,we found four Toll pathway genes(easter,spätzle,pelle,and dorsal)upregulated significantly after the knockdown of LmSPN2 while downregulated after the knockdown of LmSPN3.Therefore,we speculate that two SPNs regulate diapause through the Toll pathway.Our results indicated that LmSPN2 positively regulates locust egg entry into diapause,while LmSPN3 is a negative regulator of embryonic commitment to diapause.Their interaction is mediated by the binding site of E331 and influences egg diapause through the Toll pathway.This mechanistic understanding of diapause regulation expands our understanding of insect developmental regulation and provides functional targets for developing locust management strategies.展开更多
Potato protease inhibitors(PPIs),as the main component of potato protein isolate,have good safety,nutrition and great market potential.The antioxidant and anticancer properties of PPIs were evaluated with cellbased bi...Potato protease inhibitors(PPIs),as the main component of potato protein isolate,have good safety,nutrition and great market potential.The antioxidant and anticancer properties of PPIs were evaluated with cellbased biological assays.The results showed that when the concentration of PPIs was 5 mg/mL,the peroxyl radical scavenging value was(2119±204)mg VCE/100 g,and the cellular antioxidant activity values were(45.83±3.5)(no PBS wash)and(33.25±4.4)μmol QE/100 g(PBS wash).Cells pretreated with PPIs could significantly prevent the oxidative damage induced by H_(2)O_(2),inhibit the morphological changes of cells and maintain the integrity.Furthermore,PPIs had selective anti-proliferative effects on GIST882 cells(IC50=(10.53±3.87)mg/mL)and demonstrated potent inhibition of the growth,migration and invasion of cancer cells.These findings provide a scientific basis for PPIs as promising candidates for functional foods to aid in the prevention of oxidative damage and cancer.展开更多
Capsicum annuum L. was initially domesticated in Mexico and northern Central America, and represented an ancient Neotropical plant food complex. The purpose of this paper is to report the isolation and purification of...Capsicum annuum L. was initially domesticated in Mexico and northern Central America, and represented an ancient Neotropical plant food complex. The purpose of this paper is to report the isolation and purification of a novo-member of a protease inhibitor from jalapeño pepper (Capsicum annuum L.) (PIJP). The molecular weight of PIJP inhibitor is 5.95 kDa with 56 amino acids and 6 Cys residues with high inhibitory activity to trypsin with a Ki value of 95 nM. This inhibitor according to the alignment with homologous from NCBI and Pfam databases is a member of proteinase inhibitors II. It is worthwhile to mention a major compositional difference between the proteinase inhibitor II families which have 8 Cys residues. PIJP is the first purified proteinase inhibitor, member of this family with only 6 Cys residues.展开更多
AIM:To evaluates the effectiveness and safety of the first generation,NS3/4A protease inhibitors(PIs) in clinical practice against chronic C virus,especially in patients with advanced fibrosis. METHODS:Prospective stu...AIM:To evaluates the effectiveness and safety of the first generation,NS3/4A protease inhibitors(PIs) in clinical practice against chronic C virus,especially in patients with advanced fibrosis. METHODS:Prospective study and non-experimental analysis of a multicentre cohort of 38 Spanish hospitals that includes patients with chronic hepatitis C genotype 1,treatment-na?ve(TN) or treatment-experienced(TE),who underwent triple therapy with the first generation NS3/4A protease inhibitors,boceprevir(BOC) and telaprevir(TVR),in combination with pegylated interferon and ribavirin. The patients were treatment in routine practice settings. Data on the study population and on adverse clinical and virologic effects were compiled during the treatment period and during follow up.RESULTS:One thousand and fifty seven patients were included,405(38%) were treated with BOC and 652(62%) with TVR. Of this total,30%(n = 319) were TN and the remaining were TE:28%(n = 298) relapsers,12%(n = 123) partial responders(PR),25%(n = 260) null-responders(NR) and for 5%(n = 57) with prior response unknown. The rate of sustained virologic response(SVR) by intention-to-treatment(ITT) was greater in those treated with TVR(65%) than in those treated with BOC(52%)(P < 0.0001),whereas by modified intention-to-treatment(m ITT) no were found significant differences. By degree of fibrosis,56% of patients were F4 and the highest SVR rates were recorded in the non-F4 patients,both TN and TE. In the analysis by groups,the TN patients treated with TVR by ITT showed a higher SVR(P = 0.005). However,by m ITT there were no significant differences between BOC and TVR. In the multivariate analysis by m ITT,the significant SVR factors were relapsers,IL28 B CC and non-F4; the type of treatment(BOC or TVR) was not significant. The lowest SVR values were presented by the F4-NR patients,treated with BOC(46%) or with TVR(45%). 28% of the patients interrupted the treatment,mainly by non-viral response(51%):this outcome was more frequent in the TE than in the TN patients(57% vs 40%,P = 0.01). With respect to severe haematological disorders,neutropaenia was more likely to affect the patients treated with BOC(33% vs 20%,P ≤ 0.0001),and thrombocytopaenia and anaemia,the F4 patients(P = 0.000,P = 0.025,respectively). CONCLUSION:In a real clinical practice setting with a high proportion of patients with advanced fibrosis,effectiveness of first-generation PIs was high except for NR patients,with similar SVR rates being achieved by BOC and TVR.展开更多
Lunasin protease inhibitor concentrate(LPIC)is a novel combination of soy bioactive peptide lunasin,Kunitz and Bowman-Birk protease inhibitors.The reported anti-inflammatory and anticancer properties of each one of th...Lunasin protease inhibitor concentrate(LPIC)is a novel combination of soy bioactive peptide lunasin,Kunitz and Bowman-Birk protease inhibitors.The reported anti-inflammatory and anticancer properties of each one of them suggest LPIC as a promising candidate for the treatment of infl ammatory-related diseases.Our objective was to assess the in vivo anti-infl ammatory properties of LPIC.First,an in vitro test was performed in lipopolysaccharide(LPS)-activated RAW264.7 murine macrophages by measuring the production of nitric oxide(NO),interleukin-6(IL-6),and tumor necrosis factorα(TNF-α)as infl ammatory markers.For the in vivo model,ulcerative colitis(UC)was induced in mice via oral administration of dextran sodium sulfate(DSS).LPIC treatment was performed via daily intraperitoneal injection of 50 mg/kg body weight.Body weight,visible blood in stool and stool consistency were scored daily as macroscopic indicators of disease progression.Occult blood was evaluated by the presence of hemoglobin in stool every third day.Colon length,caecum weight,colonic myeloperoxidase activity(MPO),presence of pro-inflammatory cytokines in blood and colon,changes in the architecture,and expression of inducible nitric oxide synthase(i NOS)in colonic tissue were evaluated.In vitro,LPIC induced production of NO and maintained cytokine levels in comparison to activated untreated macrophages.In vivo,LPIC increased colonic bleeding and did not improve macroscopic markers of the disease,but reduced colonic IL-1βand IL-6,decreased systemic circulation of TNF-α,attenuated neutrophils infi ltration and i NOS expression in colonic tissue,and diminished the damage in colonic architecture.Our results suggest that combinations of peptides in LPIC may counteract the antiinfl ammatory properties in vitro;while in vivo,LPIC can signifi cantly reduce the histopathological damage,hence is a possible therapeutic strategy to attenuate UC.展开更多
Protease inhibitors have been isolated from many variable sources;however, the need to identify and characterize new molecules has increased with the discovery of new therapeutic targets and the lack of specificity of...Protease inhibitors have been isolated from many variable sources;however, the need to identify and characterize new molecules has increased with the discovery of new therapeutic targets and the lack of specificity of already identified compounds with inhibitory activity. The goal of this work was to search for inhibitory activity against four proteolytic enzymes already recognized as therapeutic targets: human neutrophil elastase, dipeptidyl peptidase IV, subtilisin from Bacillus licheniformis and cathepsin K in selected marine invertebrates from the Caribbean Sea. A systematic screening was carried out with selected aqueous extracts belonging to 20 species from seven different phyla: Annelida, Bryozoa, Chordata, Cnidaria, Equinodermata, Mollusca and Porifera, all collected at the coast of Havana (Cuba). All extracts showing initial inhibitory activity were characterized in terms of IC<sub>50</sub> values and specific inhibitory activity (SIA). Model enzymes were used in the case of human neutrophil elastase (porcine pancreatic elastase) and cathepsin K (papain) for the screening and all positive results were confirmed by testing toward the therapeutic targets. Ten extracts were identified showing inhibitory activity against human neutrophil elastase, for which the most promising values were obtained for Nerita peloronta. Only one extract, Bunodosoma granulifera, showed inhibitory activity against dipeptidyl peptidase IV with rather poor values of IC<sub>50</sub> and SIA. Seven extracts showed inhibitory activity against B. licheniformis subtilisin with very good IC<sub>50</sub> and SIA values for Lissodendorix isodyctialis, Cenchritis muricatus, and N. peloronta. Finally, eight extracts were positive for cathepsin K with almost similar parameters values among them. All these results confirmed the richness and potential of the marine invertebrate’s fauna and indicated new promising sources for the identification of natural compounds with potential application in therapeutics.展开更多
Plant derived protease inhibitors(PIs)are a promising defensin for crop im-provement and insect pest management.Although agronomist made significant efforts in utilizing PIs for managing insect pests.the potentials of...Plant derived protease inhibitors(PIs)are a promising defensin for crop im-provement and insect pest management.Although agronomist made significant efforts in utilizing PIs for managing insect pests.the potentials of PIs are still obscured.Insect ability to compensate nutrient starvation induced by dietary PI feeding using different strategies,that is,overexpression of PI-sensitive protease,expression of PI-insensitive proteases,degradation of PI,has made this innumerable collection of PIs worthless.A practical challenge for agronomist is to identify potent PI candidates,to limit insect compensatory responses and to elucidate insect compensatory and resistance mechanisms activated upon herbivory.This knowledge could be further efficiently utilized to identify potential targets for RNAi-mediated pest control.These vital genes of insects could be functionally anno-tated using the advanced gene-editing technique,CRISPR/Cas9.Contemporary research is exploiting different in silico and modern molecular biology techniques to utilize PIs in controlling insect pests efficiently.This review is structured to update recent advancements in this field,along with is chronological background.展开更多
Midgut juice plays an important role in food digestion and detoxification in insects.In order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic ac...Midgut juice plays an important role in food digestion and detoxification in insects.In order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic activity of midgut juice and its degradation of Bt proteins(Cry2A,Cry1C,Cry1Aa,and Cry1Ac)were evaluated in this study through protease inhibitor treatments.The activities of total protease in midgut juices were significantly inhibited by phenylmethylsulfonyl fluoride(PMSF),tosyl-L-lysine chloromethyl ketone(TLCK),pepstatin A and leupeptin.The enzymatic activity of chymotrypsin was significantly inhibited by PMSF,and enzymatic activity of trypsin was significantly inhibited by ethylenediaminetetraacetic acid(EDTA),PMSF,tosyl phenylalanine chloromethyl ketone(TPCK),TLCK and trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane(E-64).EDTA could significantly inhibit the degradation of Cry2A by C.medinalis.EDTA,PMSF,TPCK,and TLCK could inhibit the degradation of Cry1C and Cry1Aa.EDTA,PMSF,TPCK,TLCK,and E-64 could inhibit the degradation of Cry1Ac.Our results indicated that some protease inhibitors hindered various enzymatic activities in the larval midgut of C.medinalis,which may reduce the insect’s ability to degrade Bt toxins.These findings may aid the application of protease inhibitors in the management of this insect pest in the future.展开更多
Human alpha-2-macroglobulin is a well-known inhibitor of a broad spectrum of proteases and plays important roles in immunity,inflammation,and infections.Here,we report the cryo-EM structures of human alpha-2-macroglob...Human alpha-2-macroglobulin is a well-known inhibitor of a broad spectrum of proteases and plays important roles in immunity,inflammation,and infections.Here,we report the cryo-EM structures of human alpha-2-macroglobulin in its native state,induced state transformed by its authentic substrate,human trypsin,and serial intermediate states between the native and fully induced states.These structures exhibit distinct conformations,which reveal the dynamic transformation of alpha-2-macroglobulin that acts as a protease inhibitor.The results shed light on the molecular mechanism of alpha-2-macroglobulin in entrapping substrates.展开更多
It is hypothesized that protease inhibitors play an essential role in survival of venomous animals through protecting peptide/protein toxins from degradation by proteases in their prey or predators. However, the biolo...It is hypothesized that protease inhibitors play an essential role in survival of venomous animals through protecting peptide/protein toxins from degradation by proteases in their prey or predators. However, the biological function of protease inhibitors in scorpion venoms remains unknown. In the present study, a trypsin inhibitor was purified and characterized from the venom of scorpion Mesobuthus eupeus, which enhanced the biological activities of crude venom components in mice when injected in combination with crude venom. This protease inhibitor, named Me KTT-1, belonged to Kunitz-type toxins subfamily. Native Me KTT-1 selectively inhibited trypsin with a K_i value of 130 nmol×L^(–1). Furthermore, Me KTT-1 was shown to be a thermo-stable peptide. In animal behavioral tests, Me KTT-1 prolonged the pain behavior induced by scorpion crude venom, suggesting that protease inhibitors in scorpion venom inhibited proteases and protect the functionally important peptide/protein toxins from degradation, consequently keeping them active longer. In conclusion, this was the first experimental evidence about the natural existence of serine protease inhibitor in the venom of scorpion Mesobuthus eupeus, which preserved the activity of venom components, suggests that scorpions may use protease inhibitors for survival.展开更多
The recent outbreak of novel coronavirus pneumonia(COVID-19)caused by a new coronavirus has posed a great threat to public health.Identifying safe and effective antivirals is of urgent demand to cure the huge number o...The recent outbreak of novel coronavirus pneumonia(COVID-19)caused by a new coronavirus has posed a great threat to public health.Identifying safe and effective antivirals is of urgent demand to cure the huge number of patients.Virusencoded proteases are considered potential drug targets.The human immunodeficiency virus protease inhibitors(lopinavir/ritonavir)has been recommended in the global Solidarity Trial in March launched by World Health Organization.However,there is currently no experimental evidence to support or against its clinical use.We evaluated the antiviral efficacy of lopinavir/ritonavir along with other two viral protease inhibitors in vitro,and discussed the possible inhibitory mechanism in silico.The in vitro to in vivo extrapolation was carried out to assess whether lopinavir/ritonavir could be effective in clinical.Among the four tested compounds,lopinavir showed the best inhibitory effect against the novel coronavirus infection.However,further in vitro to in vivo extrapolation of pharmacokinetics suggested that lopinavir/ritonavir could not reach effective concentration under standard dosing regimen[marketed as Kaletraò,contained lopinavir/ritonavir(200 mg/50 mg)tablets,recommended dosage is 400 mg/10 mg(2 tablets)twice daily].This research concluded that lopinavir/ritonavir should be stopped for clinical use due to the huge gap between in vitro IC50 and free plasma concentration.Nevertheless,the structure–activity relationship analysis of the four inhibitors provided further information for de novel design of future viral protease inhibitors of SARS-CoV-2.展开更多
The gastrointestinal barrier is-with approximately 400 m^2-the human body's largest surface separating the external environment from the internal milieu. This barrier serves a dual function: permitting the absorpt...The gastrointestinal barrier is-with approximately 400 m^2-the human body's largest surface separating the external environment from the internal milieu. This barrier serves a dual function: permitting the absorption of nutrients, water and electrolytes on the one hand, while limiting host contact with noxious luminal antigens on the other hand. To maintain this selective barrier, junction protein complexes seal the intercellular space between adjacent epithelial cells and regulate the paracellular transport. Increased intestinal permeability is associated with and suggested as a player in the pathophysiology of various gastrointestinal and extraintestinal diseases such as inflammatory bowel disease, celiac disease and type 1 diabetes. The gastrointestinal tract is exposed to high levels of endogenous and exogenous proteases, both in the lumen and in the mucosa. There is increasing evidence to suggest that a dysregulation of the protease/antiprotease balance in the gut contributes to epithelial damage and increased permeability. Excessive proteolysis leads to direct cleavage of intercellular junction proteins, or to opening of the junction proteins via activation of protease activated receptors. In addition, proteases regulate the activity and availability of cytokines and growth factors, which are also known modulators of intestinal permeability. This review aims at outlining the mechanisms by which proteases alter the intestinal permeability. More knowledge on the role of proteases in mucosal homeostasis and gastrointestinal barrier function will definitely contribute to the identification of new therapeutic targets for permeability-related diseases.展开更多
Telaprevir and Boceprevir are the first direct acting antivirals approved for chronic hepatitis C in combination with peg-interferon alfa and ribavirin.Pancytopenia due to myelotoxicity caused by these drugs may occur...Telaprevir and Boceprevir are the first direct acting antivirals approved for chronic hepatitis C in combination with peg-interferon alfa and ribavirin.Pancytopenia due to myelotoxicity caused by these drugs may occur,but severe hematological abnormalities or aplastic anemia(AA) have not been described.We collected all cases of severe pancytopenia observed during triple therapy with telaprevir in four Spanish centers since approval of the drug in 2011.Among 142 cirrhotic patients receiving treatment,7 cases of severe pancytopenia(5%) were identified and three were consistent with the diagnosis of AA.Mean age was 59 years,five patients had compensated cirrhosis and two patients had severe hepatitis C recurrence after liver transplantation.Severe pancytopenia was diagnosed a median of 10 wk after the initiation of therapy.Three patients had pre-treatment hematological abnormalities related to splenomegaly.In six patients,antiviral treatment was interrupted at the onset of hematological abnormalities.Two patients died due to septic complications and one patient due to acute alveolar hemorrhage.The remaining patients recovered.Severe pancytopenia and especially AA,are not rare during triple therapy with telaprevir in patients with advanced liver disease.Close monitoring is imperative in this setting to promptly detect serious hematological disorders and to prevent further complications.展开更多
BACKGROUND Squamous cell carcinoma antigen(SCCA)is regarded as a specific indicator of epithelial malignancies and is widely used in the diagnosis of squamous cell carcinoma(SCC).However,the expression of SCCA in gast...BACKGROUND Squamous cell carcinoma antigen(SCCA)is regarded as a specific indicator of epithelial malignancies and is widely used in the diagnosis of squamous cell carcinoma(SCC).However,the expression of SCCA in gastric adenocarcinoma has not been studied in detail.CASE SUMMARY A 52-year-old man was admitted to our hospital for a 2.5 cm x 2.5 cm ulcer at the antrum-body junction with dull pain and fullness in the upper abdomen for 2 mo.His pre-surgery serological testing results showed 0.51 ng/mL SCCA(reference interval,<1.5 ng/mL)and 9.9 ng/mL carcinoembryonic antigen(reference range,<4.7 ng/mL).He underwent radical distal gastrectomy and Roux-en Y anastomosis and was diagnosed with poorly differentiated mucinous adenocarcinoma(Lauren classification:Diffuse)by pathological examination of the resected lesion.Immunohistochemistry showed that SCCA was highly expressed in the cytoplasm of cancer cells.After surgery,the patient received an S-1 adjuvant chemotherapy regimen for six cycles containing tegafur,gimeracil,and oteracil potassium.He showed no sign of recurrence or metastasis within 24-mo follow-up.CONCLUSION This is a frontal report of SCCA overexpression in poorly differentiated adenocarcinoma of the stomach.展开更多
For human immunodeficiency virus(HIV)-infected patients, the 1990s were marked by the introduction of highly active antiretroviral therapy(HAART) representing a new perspective of life for these patients. The use of H...For human immunodeficiency virus(HIV)-infected patients, the 1990s were marked by the introduction of highly active antiretroviral therapy(HAART) representing a new perspective of life for these patients. The use of HAART was shown to effectively suppress the replication of HIV-1 and dramatically reduce mortality and morbidity, which led to a better and longer quality of life for HIV-1-infected patients. Apart from the substantial benefits that result from the use of various HAART regimens, laboratory and clinical experience has shown that HAART can induce severe and considerable adverse effects related to metabolic complications of lipid metabolism, characterized by signs of lipodystrophy, insulin resistance, central adiposity, dyslipidemia, increased risk of cardiovascular disease and even an increased risk of atherosclerosis. New drugs are being studied, new therapeutic strategies are being implemented, and the use of statins, fibrates, and inhibitors of intestinal cholesterol absorption have been effective alternatives. Changes in diet and lifestyle have also shown satisfactory results.展开更多
RNA viruses are critically dependent upon virally encoded proteases to cleave the viral polyproteins into functional proteins.Many of these proteases exhibit a similar fold and contain an essential catalytic cysteine,...RNA viruses are critically dependent upon virally encoded proteases to cleave the viral polyproteins into functional proteins.Many of these proteases exhibit a similar fold and contain an essential catalytic cysteine,offering the opportunity to inhibit these enzymes with electrophilic small molecules.Here we describe the successful application of quantitative irreversible tethering(qIT)to identify acrylamide fragments that target the active site cysteine of the 3C protease(3Cpro)of Enterovirus 71,the causative agent of hand,foot and mouth disease in humans,altering the substrate binding region.Further,we re-purpose these hits towards the main protease(Mpro)of SARS-CoV-2 which shares the 3C-like fold and a similar active site.The hit fragments covalently link to the catalytic cysteine of Mpro to inhibit its activity.We demonstrate that targeting the active site cysteine of Mpro can have profound allosteric effects,distorting secondary structures to disrupt the active dimeric unit.展开更多
Plants associate with diverse microbes that exert beneficial,neutral,or pathogenic effects inside the host.During the initial stages of invasion,the plant apoplast constitutes a hospitable environment for invading mic...Plants associate with diverse microbes that exert beneficial,neutral,or pathogenic effects inside the host.During the initial stages of invasion,the plant apoplast constitutes a hospitable environment for invading microbes,providing both water and nutrients.In response to microbial infection,a number of secreted proteins from host cells accumulate in the apoplastic space,which is related to microbial association or colonization processes.However,the molecular mechanisms underlying plant modulation of the apoplast environment and how plant-secreted proteases are involved in pathogen resistance are still poorly understood.Recently,several studies have reported the roles of apoplastic proteases in plant resistance against bacteria,fungi,and oomycetes.On the other hand,microbe-secreted proteins directly and/or indirectly inhibit host-derived apoplastic proteases to promote infection.These findings illustrate the importance of apoplastic proteases in plant–microbe interactions.Therefore,understanding the protease-mediated apoplastic battle between hosts and pathogens is of fundamental importance for understanding plant–pathogen interactions.Here,we provide an overviewof plant–microbe interactions in the apoplastic space.We define the apoplast,summarize the physical and chemical properties of these structures,and discuss the roles of plant apoplastic proteases and pathogen protease inhibitors in host–microbe interactions.Challenges and future perspectives for research into protease-mediated apoplastic interactions are discussed,which may facilitate the engineering of resistant crops.展开更多
Hypoxia,as an important hallmark of the tumor microenvironment,is a major cause of oxidative stress and plays a central role in various malignant tumors,including glioblastoma.Elevated reactive oxygen species(ROS)in a...Hypoxia,as an important hallmark of the tumor microenvironment,is a major cause of oxidative stress and plays a central role in various malignant tumors,including glioblastoma.Elevated reactive oxygen species(ROS)in a hypoxic microenvironment promote glioblastoma progression;however,the underlying mechanism has not been clarified.Herein,we found that hypoxia promoted ROS production,and the proliferation,migration,and invasion of glioblastoma cells,while this promotion was restrained by ROS scavengers N-acetyl-L-cysteine(NAC)and diphenyleneiodonium chloride(DPI).Hypoxia-induced ROS activated hypoxia-inducible factor-1α(HIF-1α)signaling,which enhanced cell migration and invasion by epithelial-mesenchymal transition(EMT).Furthermore,the induction of serine protease inhibitor family E member 1(SERPINE1)was ROS-dependent under hypoxia,and HIF-1αmediated SERPINE1 increase induced by ROS via binding to the SERPINE1 promoter region,thereby facilitating glioblastoma migration and invasion.Taken together,our data revealed that hypoxia-induced ROS reinforce the hypoxic adaptation of glioblastoma by driving the HIF-1α-SERPINE1 signaling pathway,and that targeting ROS may be a promising therapeutic strategy for glioblastoma.展开更多
COVID-19 has become a global public health crisis since its outbreak in China in December 2019.Currently there are few clinically effective drugs to combat SARS-CoV-2 infection.The main protein(M^(pro)),papain-like pr...COVID-19 has become a global public health crisis since its outbreak in China in December 2019.Currently there are few clinically effective drugs to combat SARS-CoV-2 infection.The main protein(M^(pro)),papain-like protease(PL^(pro))and RNA-dependent RNA polymerase(RdRp)of SARS-CoV-2 are involved in the viral replication,and might be prospective targets for anti-coronavirus drug development.Here,we investigated the antiviral activity of oridonin,a natural small-molecule compound,against SARS-CoV-2 infection in vitro.The time-of-addition analysis showed that oridonin efficiently inhibited SARS-CoV-2 infection by interfering with the genome replication at the post-entry stage.Mechanistically,the inhibition of viral replication by oridonin depends on the oxidation activity ofα,β-unsaturated carbonyl.Further experiments showed that oridonin not only effectively inhibited SARS-CoV-2 Mpro activity,but also had some inhibitory effects on PLpro-mediated deubiquitinating and viral polymerase-catalyzed RNA elongation activities at high concentrations.In particular,oridonin could inhibit the bat SARS-like CoV and the newly emerged SARS-CoV-2 omicron variants(BA.1 and BA.2),which highlights its potential as a pan-coronavirus antiviral agent.Overall,our data provide strong evidence that oridonin is an efficient antiviral agent against SARS-CoV-2 infection.展开更多
Background:Enterovirus 71(EV71)is a major virus that causes hand-foot-mouth disease.In cases of infants and young children,EV71 infection has been associated with severe neurological disease and potentially fatal syst...Background:Enterovirus 71(EV71)is a major virus that causes hand-foot-mouth disease.In cases of infants and young children,EV71 infection has been associated with severe neurological disease and potentially fatal systemic complications.The sporadic outbreak worldwide is increasingly prevalent in the Asia-Pacific region,where it has become a major public health concern.Objective:No specific antiviral drugs are currently approved for the treatment of EV71 infection.The purpose of this study is to comprehensively review the research progress of anti-EV71 drugs(synthetic small molecule inhibitors and nature drugs)in the past twenty years,and further to promote the research and development of antiviral drugs against enterovirus infection.Methods:This study reviewed the drugs on anti EV71 in the past decades.The literature search in PubMed database was conducted for original studies and review articles on drugs against enterovirus 71.Related articles published in English were selected for study and discussion.Results:As reviewed in this paper,bioactive molecules include receptor analogues,protease inhibitors,natural drugs derived from traditional chinese medicine or natural medicine.These bioactive molecules have shown significant effectiveness in inhibiting the entry and replication of EV71 in vitro and in vivo experiments.Conclusion:This review demonstrated that the entry receptor of EV71 into host cells has been studied,and receptor drugs against enterovirus have been made some progress,but most receptor analogues have not been reported.Further research is needed in this area in the future.On the other hand,the protease inhibitors have always been a major aspect of anti-enterovirus research and can be developed as antiviral agents for clinical application.In terms of natural drugs,many monomers derived from traditional chinese medicine or natural medicine have good antiviral activity and little toxic and side effects on host cells,but in view of their multi-target properties,the mechanism of drug action needs to be further studied.展开更多
基金This work was supported by the National Key R&D Program of China(2022YFD1400500)the China Agriculture Research System of MOF and MARA(CARS-34-07)+1 种基金the Publicinterest Scientific Institution Basal Research Fund,China(Y2022GH12)the Central Public-interest Scientific Institution Basal Research Fund,China(S2021XM22 and S2022XM21)。
文摘Female adults of the migratory locust,Locusta migratoria manilensis(Meyen),can sense seasonal photoperiod changes,which induces embryonic diapause as a key strategy to overwinter.Serine protease inhibitor genes(SPNs)were thought to play key roles during diapause,while few SPNs were functionally characterized.LmSPN2 was one of those genes differentially expressed between diapause and non-diapause eggs;however,its biological function remained to be explored.So,we conducted RNAi knockdown of LmSPN2,resulting in a significant decrease of the egg diapause rate by 29.7%.Using yeast two-hybrid assays,co-immunoprecipitation,and pull-down methods,we found an interaction between LmSPN2 and LmSPN3,which was proved to be mediated by a glutamate(E331)binding site of LmSPN2.RNAi knockdown of LmSPN3 resulted in a significant increase in diapause rate by 14.6%,indicating an inverse function of LmSPN2 and LmSPN3 on diapause regulation.Double knockdown of two SPN genes resulted in a 26.4%reduction in diapause rate,indicating that LmSPN2 was the dominant regulatory signal.Moreover,we found four Toll pathway genes(easter,spätzle,pelle,and dorsal)upregulated significantly after the knockdown of LmSPN2 while downregulated after the knockdown of LmSPN3.Therefore,we speculate that two SPNs regulate diapause through the Toll pathway.Our results indicated that LmSPN2 positively regulates locust egg entry into diapause,while LmSPN3 is a negative regulator of embryonic commitment to diapause.Their interaction is mediated by the binding site of E331 and influences egg diapause through the Toll pathway.This mechanistic understanding of diapause regulation expands our understanding of insect developmental regulation and provides functional targets for developing locust management strategies.
基金supported by the Science and Technology Mission Project of Liaoning Province Science and Technology Council(2021JH5/10400016)the Service Local Project of Liaoning Provincial Committee of Education(LSNFW202002)the Science and Technology Mission Project of Shenyang Science and Technology Council(20-207-3-25)。
文摘Potato protease inhibitors(PPIs),as the main component of potato protein isolate,have good safety,nutrition and great market potential.The antioxidant and anticancer properties of PPIs were evaluated with cellbased biological assays.The results showed that when the concentration of PPIs was 5 mg/mL,the peroxyl radical scavenging value was(2119±204)mg VCE/100 g,and the cellular antioxidant activity values were(45.83±3.5)(no PBS wash)and(33.25±4.4)μmol QE/100 g(PBS wash).Cells pretreated with PPIs could significantly prevent the oxidative damage induced by H_(2)O_(2),inhibit the morphological changes of cells and maintain the integrity.Furthermore,PPIs had selective anti-proliferative effects on GIST882 cells(IC50=(10.53±3.87)mg/mL)and demonstrated potent inhibition of the growth,migration and invasion of cancer cells.These findings provide a scientific basis for PPIs as promising candidates for functional foods to aid in the prevention of oxidative damage and cancer.
基金DGAPA-UNAM,Project PAPIIT IN200711J.P.Carrillo Montes thanks CONACyT for his fellowship(206846).
文摘Capsicum annuum L. was initially domesticated in Mexico and northern Central America, and represented an ancient Neotropical plant food complex. The purpose of this paper is to report the isolation and purification of a novo-member of a protease inhibitor from jalapeño pepper (Capsicum annuum L.) (PIJP). The molecular weight of PIJP inhibitor is 5.95 kDa with 56 amino acids and 6 Cys residues with high inhibitory activity to trypsin with a Ki value of 95 nM. This inhibitor according to the alignment with homologous from NCBI and Pfam databases is a member of proteinase inhibitors II. It is worthwhile to mention a major compositional difference between the proteinase inhibitor II families which have 8 Cys residues. PIJP is the first purified proteinase inhibitor, member of this family with only 6 Cys residues.
文摘AIM:To evaluates the effectiveness and safety of the first generation,NS3/4A protease inhibitors(PIs) in clinical practice against chronic C virus,especially in patients with advanced fibrosis. METHODS:Prospective study and non-experimental analysis of a multicentre cohort of 38 Spanish hospitals that includes patients with chronic hepatitis C genotype 1,treatment-na?ve(TN) or treatment-experienced(TE),who underwent triple therapy with the first generation NS3/4A protease inhibitors,boceprevir(BOC) and telaprevir(TVR),in combination with pegylated interferon and ribavirin. The patients were treatment in routine practice settings. Data on the study population and on adverse clinical and virologic effects were compiled during the treatment period and during follow up.RESULTS:One thousand and fifty seven patients were included,405(38%) were treated with BOC and 652(62%) with TVR. Of this total,30%(n = 319) were TN and the remaining were TE:28%(n = 298) relapsers,12%(n = 123) partial responders(PR),25%(n = 260) null-responders(NR) and for 5%(n = 57) with prior response unknown. The rate of sustained virologic response(SVR) by intention-to-treatment(ITT) was greater in those treated with TVR(65%) than in those treated with BOC(52%)(P < 0.0001),whereas by modified intention-to-treatment(m ITT) no were found significant differences. By degree of fibrosis,56% of patients were F4 and the highest SVR rates were recorded in the non-F4 patients,both TN and TE. In the analysis by groups,the TN patients treated with TVR by ITT showed a higher SVR(P = 0.005). However,by m ITT there were no significant differences between BOC and TVR. In the multivariate analysis by m ITT,the significant SVR factors were relapsers,IL28 B CC and non-F4; the type of treatment(BOC or TVR) was not significant. The lowest SVR values were presented by the F4-NR patients,treated with BOC(46%) or with TVR(45%). 28% of the patients interrupted the treatment,mainly by non-viral response(51%):this outcome was more frequent in the TE than in the TN patients(57% vs 40%,P = 0.01). With respect to severe haematological disorders,neutropaenia was more likely to affect the patients treated with BOC(33% vs 20%,P ≤ 0.0001),and thrombocytopaenia and anaemia,the F4 patients(P = 0.000,P = 0.025,respectively). CONCLUSION:In a real clinical practice setting with a high proportion of patients with advanced fibrosis,effectiveness of first-generation PIs was high except for NR patients,with similar SVR rates being achieved by BOC and TVR.
基金partially supported by HATCH 1010230 and Hatch Project TEN00487partially supported by COLCIENCIAS-FULBRIGHT cohort 2017。
文摘Lunasin protease inhibitor concentrate(LPIC)is a novel combination of soy bioactive peptide lunasin,Kunitz and Bowman-Birk protease inhibitors.The reported anti-inflammatory and anticancer properties of each one of them suggest LPIC as a promising candidate for the treatment of infl ammatory-related diseases.Our objective was to assess the in vivo anti-infl ammatory properties of LPIC.First,an in vitro test was performed in lipopolysaccharide(LPS)-activated RAW264.7 murine macrophages by measuring the production of nitric oxide(NO),interleukin-6(IL-6),and tumor necrosis factorα(TNF-α)as infl ammatory markers.For the in vivo model,ulcerative colitis(UC)was induced in mice via oral administration of dextran sodium sulfate(DSS).LPIC treatment was performed via daily intraperitoneal injection of 50 mg/kg body weight.Body weight,visible blood in stool and stool consistency were scored daily as macroscopic indicators of disease progression.Occult blood was evaluated by the presence of hemoglobin in stool every third day.Colon length,caecum weight,colonic myeloperoxidase activity(MPO),presence of pro-inflammatory cytokines in blood and colon,changes in the architecture,and expression of inducible nitric oxide synthase(i NOS)in colonic tissue were evaluated.In vitro,LPIC induced production of NO and maintained cytokine levels in comparison to activated untreated macrophages.In vivo,LPIC increased colonic bleeding and did not improve macroscopic markers of the disease,but reduced colonic IL-1βand IL-6,decreased systemic circulation of TNF-α,attenuated neutrophils infi ltration and i NOS expression in colonic tissue,and diminished the damage in colonic architecture.Our results suggest that combinations of peptides in LPIC may counteract the antiinfl ammatory properties in vitro;while in vivo,LPIC can signifi cantly reduce the histopathological damage,hence is a possible therapeutic strategy to attenuate UC.
文摘Protease inhibitors have been isolated from many variable sources;however, the need to identify and characterize new molecules has increased with the discovery of new therapeutic targets and the lack of specificity of already identified compounds with inhibitory activity. The goal of this work was to search for inhibitory activity against four proteolytic enzymes already recognized as therapeutic targets: human neutrophil elastase, dipeptidyl peptidase IV, subtilisin from Bacillus licheniformis and cathepsin K in selected marine invertebrates from the Caribbean Sea. A systematic screening was carried out with selected aqueous extracts belonging to 20 species from seven different phyla: Annelida, Bryozoa, Chordata, Cnidaria, Equinodermata, Mollusca and Porifera, all collected at the coast of Havana (Cuba). All extracts showing initial inhibitory activity were characterized in terms of IC<sub>50</sub> values and specific inhibitory activity (SIA). Model enzymes were used in the case of human neutrophil elastase (porcine pancreatic elastase) and cathepsin K (papain) for the screening and all positive results were confirmed by testing toward the therapeutic targets. Ten extracts were identified showing inhibitory activity against human neutrophil elastase, for which the most promising values were obtained for Nerita peloronta. Only one extract, Bunodosoma granulifera, showed inhibitory activity against dipeptidyl peptidase IV with rather poor values of IC<sub>50</sub> and SIA. Seven extracts showed inhibitory activity against B. licheniformis subtilisin with very good IC<sub>50</sub> and SIA values for Lissodendorix isodyctialis, Cenchritis muricatus, and N. peloronta. Finally, eight extracts were positive for cathepsin K with almost similar parameters values among them. All these results confirmed the richness and potential of the marine invertebrate’s fauna and indicated new promising sources for the identification of natural compounds with potential application in therapeutics.
文摘Plant derived protease inhibitors(PIs)are a promising defensin for crop im-provement and insect pest management.Although agronomist made significant efforts in utilizing PIs for managing insect pests.the potentials of PIs are still obscured.Insect ability to compensate nutrient starvation induced by dietary PI feeding using different strategies,that is,overexpression of PI-sensitive protease,expression of PI-insensitive proteases,degradation of PI,has made this innumerable collection of PIs worthless.A practical challenge for agronomist is to identify potent PI candidates,to limit insect compensatory responses and to elucidate insect compensatory and resistance mechanisms activated upon herbivory.This knowledge could be further efficiently utilized to identify potential targets for RNAi-mediated pest control.These vital genes of insects could be functionally anno-tated using the advanced gene-editing technique,CRISPR/Cas9.Contemporary research is exploiting different in silico and modern molecular biology techniques to utilize PIs in controlling insect pests efficiently.This review is structured to update recent advancements in this field,along with is chronological background.
基金This study was supported by the Zhejiang Provincial Natural Science Foundation of China(LY20C140004)the National Science and Technology Major Project of China(2016ZX08001001)+1 种基金the National Natural Science Foundation of China(31501669)the earmarked fund for China Agriculture Research System(CARS-01-36).
文摘Midgut juice plays an important role in food digestion and detoxification in insects.In order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic activity of midgut juice and its degradation of Bt proteins(Cry2A,Cry1C,Cry1Aa,and Cry1Ac)were evaluated in this study through protease inhibitor treatments.The activities of total protease in midgut juices were significantly inhibited by phenylmethylsulfonyl fluoride(PMSF),tosyl-L-lysine chloromethyl ketone(TLCK),pepstatin A and leupeptin.The enzymatic activity of chymotrypsin was significantly inhibited by PMSF,and enzymatic activity of trypsin was significantly inhibited by ethylenediaminetetraacetic acid(EDTA),PMSF,tosyl phenylalanine chloromethyl ketone(TPCK),TLCK and trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane(E-64).EDTA could significantly inhibit the degradation of Cry2A by C.medinalis.EDTA,PMSF,TPCK,and TLCK could inhibit the degradation of Cry1C and Cry1Aa.EDTA,PMSF,TPCK,TLCK,and E-64 could inhibit the degradation of Cry1Ac.Our results indicated that some protease inhibitors hindered various enzymatic activities in the larval midgut of C.medinalis,which may reduce the insect’s ability to degrade Bt toxins.These findings may aid the application of protease inhibitors in the management of this insect pest in the future.
基金supported by the National Natural Science Foundation of China(31971154,31730023,31521002)the Chinese Ministry of Science and Technology(2017YFA0504700,2021YFA1300100)+1 种基金the Chinese Academy of Sciences(CAS)(XDB37010100)the National Laboratory of Biomacromolecules of China(2019KF07)。
文摘Human alpha-2-macroglobulin is a well-known inhibitor of a broad spectrum of proteases and plays important roles in immunity,inflammation,and infections.Here,we report the cryo-EM structures of human alpha-2-macroglobulin in its native state,induced state transformed by its authentic substrate,human trypsin,and serial intermediate states between the native and fully induced states.These structures exhibit distinct conformations,which reveal the dynamic transformation of alpha-2-macroglobulin that acts as a protease inhibitor.The results shed light on the molecular mechanism of alpha-2-macroglobulin in entrapping substrates.
基金supported by MOST(2013CB911300,2010CB529800)NSFC(Nos.31025025,31025025,U1132601,31200590)+1 种基金CAS(SAJC201308)Yunnan Province(2011CI139,2012BC009)
文摘It is hypothesized that protease inhibitors play an essential role in survival of venomous animals through protecting peptide/protein toxins from degradation by proteases in their prey or predators. However, the biological function of protease inhibitors in scorpion venoms remains unknown. In the present study, a trypsin inhibitor was purified and characterized from the venom of scorpion Mesobuthus eupeus, which enhanced the biological activities of crude venom components in mice when injected in combination with crude venom. This protease inhibitor, named Me KTT-1, belonged to Kunitz-type toxins subfamily. Native Me KTT-1 selectively inhibited trypsin with a K_i value of 130 nmol×L^(–1). Furthermore, Me KTT-1 was shown to be a thermo-stable peptide. In animal behavioral tests, Me KTT-1 prolonged the pain behavior induced by scorpion crude venom, suggesting that protease inhibitors in scorpion venom inhibited proteases and protect the functionally important peptide/protein toxins from degradation, consequently keeping them active longer. In conclusion, this was the first experimental evidence about the natural existence of serine protease inhibitor in the venom of scorpion Mesobuthus eupeus, which preserved the activity of venom components, suggests that scorpions may use protease inhibitors for survival.
基金supported in part by grants from the National Science and Technology Major Projects(Grant Number 2018ZX09711003)National Key Research and Development Project(2020YFC0841700)+1 种基金the National Natural Science Foundation of China(Grant Number 31621061)the Hubei Science and Technology Project(Grant Number 2020FCA003)。
文摘The recent outbreak of novel coronavirus pneumonia(COVID-19)caused by a new coronavirus has posed a great threat to public health.Identifying safe and effective antivirals is of urgent demand to cure the huge number of patients.Virusencoded proteases are considered potential drug targets.The human immunodeficiency virus protease inhibitors(lopinavir/ritonavir)has been recommended in the global Solidarity Trial in March launched by World Health Organization.However,there is currently no experimental evidence to support or against its clinical use.We evaluated the antiviral efficacy of lopinavir/ritonavir along with other two viral protease inhibitors in vitro,and discussed the possible inhibitory mechanism in silico.The in vitro to in vivo extrapolation was carried out to assess whether lopinavir/ritonavir could be effective in clinical.Among the four tested compounds,lopinavir showed the best inhibitory effect against the novel coronavirus infection.However,further in vitro to in vivo extrapolation of pharmacokinetics suggested that lopinavir/ritonavir could not reach effective concentration under standard dosing regimen[marketed as Kaletraò,contained lopinavir/ritonavir(200 mg/50 mg)tablets,recommended dosage is 400 mg/10 mg(2 tablets)twice daily].This research concluded that lopinavir/ritonavir should be stopped for clinical use due to the huge gap between in vitro IC50 and free plasma concentration.Nevertheless,the structure–activity relationship analysis of the four inhibitors provided further information for de novel design of future viral protease inhibitors of SARS-CoV-2.
文摘The gastrointestinal barrier is-with approximately 400 m^2-the human body's largest surface separating the external environment from the internal milieu. This barrier serves a dual function: permitting the absorption of nutrients, water and electrolytes on the one hand, while limiting host contact with noxious luminal antigens on the other hand. To maintain this selective barrier, junction protein complexes seal the intercellular space between adjacent epithelial cells and regulate the paracellular transport. Increased intestinal permeability is associated with and suggested as a player in the pathophysiology of various gastrointestinal and extraintestinal diseases such as inflammatory bowel disease, celiac disease and type 1 diabetes. The gastrointestinal tract is exposed to high levels of endogenous and exogenous proteases, both in the lumen and in the mucosa. There is increasing evidence to suggest that a dysregulation of the protease/antiprotease balance in the gut contributes to epithelial damage and increased permeability. Excessive proteolysis leads to direct cleavage of intercellular junction proteins, or to opening of the junction proteins via activation of protease activated receptors. In addition, proteases regulate the activity and availability of cytokines and growth factors, which are also known modulators of intestinal permeability. This review aims at outlining the mechanisms by which proteases alter the intestinal permeability. More knowledge on the role of proteases in mucosal homeostasis and gastrointestinal barrier function will definitely contribute to the identification of new therapeutic targets for permeability-related diseases.
基金(in part)Instituto de Salud Carlos III(PI11/01907),Ministerio de Economia y Competitividad,co-funded by Fondo Europeo de Desarrollo Regional,Union Europea,Una manera de hacer EuropaRoche Organ Transplantation Research Foundation(ROTRF,CI:442035057)(all to Forns X)
文摘Telaprevir and Boceprevir are the first direct acting antivirals approved for chronic hepatitis C in combination with peg-interferon alfa and ribavirin.Pancytopenia due to myelotoxicity caused by these drugs may occur,but severe hematological abnormalities or aplastic anemia(AA) have not been described.We collected all cases of severe pancytopenia observed during triple therapy with telaprevir in four Spanish centers since approval of the drug in 2011.Among 142 cirrhotic patients receiving treatment,7 cases of severe pancytopenia(5%) were identified and three were consistent with the diagnosis of AA.Mean age was 59 years,five patients had compensated cirrhosis and two patients had severe hepatitis C recurrence after liver transplantation.Severe pancytopenia was diagnosed a median of 10 wk after the initiation of therapy.Three patients had pre-treatment hematological abnormalities related to splenomegaly.In six patients,antiviral treatment was interrupted at the onset of hematological abnormalities.Two patients died due to septic complications and one patient due to acute alveolar hemorrhage.The remaining patients recovered.Severe pancytopenia and especially AA,are not rare during triple therapy with telaprevir in patients with advanced liver disease.Close monitoring is imperative in this setting to promptly detect serious hematological disorders and to prevent further complications.
基金The Six Top Talent Project of Jiangsu Province,No.WSW-004National Natural Science Foundation of China,No.81671836and Key Laboratory for Laboratory Medicine of Jiangsu Province of China,No.ZDXKB2016005.
文摘BACKGROUND Squamous cell carcinoma antigen(SCCA)is regarded as a specific indicator of epithelial malignancies and is widely used in the diagnosis of squamous cell carcinoma(SCC).However,the expression of SCCA in gastric adenocarcinoma has not been studied in detail.CASE SUMMARY A 52-year-old man was admitted to our hospital for a 2.5 cm x 2.5 cm ulcer at the antrum-body junction with dull pain and fullness in the upper abdomen for 2 mo.His pre-surgery serological testing results showed 0.51 ng/mL SCCA(reference interval,<1.5 ng/mL)and 9.9 ng/mL carcinoembryonic antigen(reference range,<4.7 ng/mL).He underwent radical distal gastrectomy and Roux-en Y anastomosis and was diagnosed with poorly differentiated mucinous adenocarcinoma(Lauren classification:Diffuse)by pathological examination of the resected lesion.Immunohistochemistry showed that SCCA was highly expressed in the cytoplasm of cancer cells.After surgery,the patient received an S-1 adjuvant chemotherapy regimen for six cycles containing tegafur,gimeracil,and oteracil potassium.He showed no sign of recurrence or metastasis within 24-mo follow-up.CONCLUSION This is a frontal report of SCCA overexpression in poorly differentiated adenocarcinoma of the stomach.
基金financially supported in the our laboratory with resources from The National Council of Technological and Scientific Developmentthe State of Sao Paulo Research Foundationthe National Institute of Science and Technology of Complex Fluids.
文摘For human immunodeficiency virus(HIV)-infected patients, the 1990s were marked by the introduction of highly active antiretroviral therapy(HAART) representing a new perspective of life for these patients. The use of HAART was shown to effectively suppress the replication of HIV-1 and dramatically reduce mortality and morbidity, which led to a better and longer quality of life for HIV-1-infected patients. Apart from the substantial benefits that result from the use of various HAART regimens, laboratory and clinical experience has shown that HAART can induce severe and considerable adverse effects related to metabolic complications of lipid metabolism, characterized by signs of lipodystrophy, insulin resistance, central adiposity, dyslipidemia, increased risk of cardiovascular disease and even an increased risk of atherosclerosis. New drugs are being studied, new therapeutic strategies are being implemented, and the use of statins, fibrates, and inhibitors of intestinal cholesterol absorption have been effective alternatives. Changes in diet and lifestyle have also shown satisfactory results.
基金supported by grants from Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Sciences (2021-I2M-1-037, China)National Key Research and Development Program of China (2016YFD0500300)+5 种基金the CRP-ICGEB Research Grant 2019 (CRP/CHN19-02, China)supported by grants from the Institute of Chemical Biology (Imperial College London, UK)the UK Engineering and Physical Sciences Research Council (Studentship award EP/F500416/1, UK)The Imperial College COVID19 Research FundThe crystallization facility at Imperial College was funded by BBSRC (BB/ D524840/1, UK)the Wellcome Trust (202926/Z/16/Z, UK)
文摘RNA viruses are critically dependent upon virally encoded proteases to cleave the viral polyproteins into functional proteins.Many of these proteases exhibit a similar fold and contain an essential catalytic cysteine,offering the opportunity to inhibit these enzymes with electrophilic small molecules.Here we describe the successful application of quantitative irreversible tethering(qIT)to identify acrylamide fragments that target the active site cysteine of the 3C protease(3Cpro)of Enterovirus 71,the causative agent of hand,foot and mouth disease in humans,altering the substrate binding region.Further,we re-purpose these hits towards the main protease(Mpro)of SARS-CoV-2 which shares the 3C-like fold and a similar active site.The hit fragments covalently link to the catalytic cysteine of Mpro to inhibit its activity.We demonstrate that targeting the active site cysteine of Mpro can have profound allosteric effects,distorting secondary structures to disrupt the active dimeric unit.
文摘Plants associate with diverse microbes that exert beneficial,neutral,or pathogenic effects inside the host.During the initial stages of invasion,the plant apoplast constitutes a hospitable environment for invading microbes,providing both water and nutrients.In response to microbial infection,a number of secreted proteins from host cells accumulate in the apoplastic space,which is related to microbial association or colonization processes.However,the molecular mechanisms underlying plant modulation of the apoplast environment and how plant-secreted proteases are involved in pathogen resistance are still poorly understood.Recently,several studies have reported the roles of apoplastic proteases in plant resistance against bacteria,fungi,and oomycetes.On the other hand,microbe-secreted proteins directly and/or indirectly inhibit host-derived apoplastic proteases to promote infection.These findings illustrate the importance of apoplastic proteases in plant–microbe interactions.Therefore,understanding the protease-mediated apoplastic battle between hosts and pathogens is of fundamental importance for understanding plant–pathogen interactions.Here,we provide an overviewof plant–microbe interactions in the apoplastic space.We define the apoplast,summarize the physical and chemical properties of these structures,and discuss the roles of plant apoplastic proteases and pathogen protease inhibitors in host–microbe interactions.Challenges and future perspectives for research into protease-mediated apoplastic interactions are discussed,which may facilitate the engineering of resistant crops.
基金This work was supported by the National Natural Science Foundation of China(Nos.81772688 and 81372698)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)+1 种基金the Research Foundation for Talented Scholars of Xuzhou Medical University(No.RC20552223)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX20_2463),China。
文摘Hypoxia,as an important hallmark of the tumor microenvironment,is a major cause of oxidative stress and plays a central role in various malignant tumors,including glioblastoma.Elevated reactive oxygen species(ROS)in a hypoxic microenvironment promote glioblastoma progression;however,the underlying mechanism has not been clarified.Herein,we found that hypoxia promoted ROS production,and the proliferation,migration,and invasion of glioblastoma cells,while this promotion was restrained by ROS scavengers N-acetyl-L-cysteine(NAC)and diphenyleneiodonium chloride(DPI).Hypoxia-induced ROS activated hypoxia-inducible factor-1α(HIF-1α)signaling,which enhanced cell migration and invasion by epithelial-mesenchymal transition(EMT).Furthermore,the induction of serine protease inhibitor family E member 1(SERPINE1)was ROS-dependent under hypoxia,and HIF-1αmediated SERPINE1 increase induced by ROS via binding to the SERPINE1 promoter region,thereby facilitating glioblastoma migration and invasion.Taken together,our data revealed that hypoxia-induced ROS reinforce the hypoxic adaptation of glioblastoma by driving the HIF-1α-SERPINE1 signaling pathway,and that targeting ROS may be a promising therapeutic strategy for glioblastoma.
基金the Creative Research Group Program of Natural Science Foundation of Hubei Province(2022CFA021)the China Postdoctoral Science Foundation(2022M720895)+1 种基金the National Natural Science Foundation of China(3210011 and 32200132)the Natural Science Foundation of Hubei Province,China(2017CFB535).
文摘COVID-19 has become a global public health crisis since its outbreak in China in December 2019.Currently there are few clinically effective drugs to combat SARS-CoV-2 infection.The main protein(M^(pro)),papain-like protease(PL^(pro))and RNA-dependent RNA polymerase(RdRp)of SARS-CoV-2 are involved in the viral replication,and might be prospective targets for anti-coronavirus drug development.Here,we investigated the antiviral activity of oridonin,a natural small-molecule compound,against SARS-CoV-2 infection in vitro.The time-of-addition analysis showed that oridonin efficiently inhibited SARS-CoV-2 infection by interfering with the genome replication at the post-entry stage.Mechanistically,the inhibition of viral replication by oridonin depends on the oxidation activity ofα,β-unsaturated carbonyl.Further experiments showed that oridonin not only effectively inhibited SARS-CoV-2 Mpro activity,but also had some inhibitory effects on PLpro-mediated deubiquitinating and viral polymerase-catalyzed RNA elongation activities at high concentrations.In particular,oridonin could inhibit the bat SARS-like CoV and the newly emerged SARS-CoV-2 omicron variants(BA.1 and BA.2),which highlights its potential as a pan-coronavirus antiviral agent.Overall,our data provide strong evidence that oridonin is an efficient antiviral agent against SARS-CoV-2 infection.
基金supported financially by the National Natural Science Foundation of China(82101630).
文摘Background:Enterovirus 71(EV71)is a major virus that causes hand-foot-mouth disease.In cases of infants and young children,EV71 infection has been associated with severe neurological disease and potentially fatal systemic complications.The sporadic outbreak worldwide is increasingly prevalent in the Asia-Pacific region,where it has become a major public health concern.Objective:No specific antiviral drugs are currently approved for the treatment of EV71 infection.The purpose of this study is to comprehensively review the research progress of anti-EV71 drugs(synthetic small molecule inhibitors and nature drugs)in the past twenty years,and further to promote the research and development of antiviral drugs against enterovirus infection.Methods:This study reviewed the drugs on anti EV71 in the past decades.The literature search in PubMed database was conducted for original studies and review articles on drugs against enterovirus 71.Related articles published in English were selected for study and discussion.Results:As reviewed in this paper,bioactive molecules include receptor analogues,protease inhibitors,natural drugs derived from traditional chinese medicine or natural medicine.These bioactive molecules have shown significant effectiveness in inhibiting the entry and replication of EV71 in vitro and in vivo experiments.Conclusion:This review demonstrated that the entry receptor of EV71 into host cells has been studied,and receptor drugs against enterovirus have been made some progress,but most receptor analogues have not been reported.Further research is needed in this area in the future.On the other hand,the protease inhibitors have always been a major aspect of anti-enterovirus research and can be developed as antiviral agents for clinical application.In terms of natural drugs,many monomers derived from traditional chinese medicine or natural medicine have good antiviral activity and little toxic and side effects on host cells,but in view of their multi-target properties,the mechanism of drug action needs to be further studied.
