Parkinson’s disease is a common neurodegenerative disorder that is associated with abnormal aggregation and accumulation of neurotoxic proteins,includingα-synuclein,amyloid-β,and tau,in addition to the impaired eli...Parkinson’s disease is a common neurodegenerative disorder that is associated with abnormal aggregation and accumulation of neurotoxic proteins,includingα-synuclein,amyloid-β,and tau,in addition to the impaired elimination of these neurotoxic protein.Atypical parkinsonism,which has the same clinical presentation and neuropathology as Parkinson’s disease,expands the disease landscape within the continuum of Parkinson’s disease and related disorders.The glymphatic system is a waste clearance system in the brain,which is responsible for eliminating the neurotoxic proteins from the interstitial fluid.Impairment of the glymphatic system has been proposed as a significant contributor to the development and progression of neurodegenerative disease,as it exacerbates the aggregation of neurotoxic proteins and deteriorates neuronal damage.Therefore,impairment of the glymphatic system could be considered as the final common pathway to neurodegeneration.Previous evidence has provided initial insights into the potential effect of the impaired glymphatic system on Parkinson’s disease and related disorders;however,many unanswered questions remain.This review aims to provide a comprehensive summary of the growing literature on the glymphatic system in Parkinson’s disease and related disorders.The focus of this review is on identifying the manifestations and mechanisms of interplay between the glymphatic system and neurotoxic proteins,including loss of polarization of aquaporin-4 in astrocytic endfeet,sleep and circadian rhythms,neuroinflammation,astrogliosis,and gliosis.This review further delves into the underlying pathophysiology of the glymphatic system in Parkinson’s disease and related disorders,and the potential implications of targeting the glymphatic system as a novel and promising therapeutic strategy.展开更多
Cotton provides the most abundant natural fiber for the textile industry.The mature cotton fiber largely consists of secondary cell walls with the highest proportion of cellulose and a small amount of hemicellulose an...Cotton provides the most abundant natural fiber for the textile industry.The mature cotton fiber largely consists of secondary cell walls with the highest proportion of cellulose and a small amount of hemicellulose and lignin.To dissect the roles of hemicellulosic polysaccharides during fiber development,four IRREGULAR XYLEM 15(IRX15)genes,GhIRX15-1/-2/-3/-4,were functionally characterized in cotton.These genes encode DUF579 domain-containing proteins,which are homologs of AtIRX15 involved in xylan biosynthesis.The four GhIRX15 genes were predominantly expressed during fiber secondary wall thickening,and the encoded proteins were localized to the Golgi apparatus.Each GhIRX15 gene could restore the xylan deficient phenotype in the Arabidopsis irx15irx15l double mutant.Silencing of GhIRX15s in cotton resulted in shorter mature fibers with a thinner cell wall and reduced cellulose content as compared to the wild type.Intriguingly,GhIRX15-2 and GhIRX15-4 formed homodimers and heterodimers.In addition,the GhIRX15s showed physical interaction with glycosyltransferases GhGT43C,GhGT47A and GhGT47B,which are responsible for synthesis of the xylan backbone and reducing end sequence.Moreover,the GhIRX15s can form heterocomplexes with enzymes involved in xylan modification and side chain synthesis,such as GhGUX1/2,GhGXM1/2 and GhTBL1.These findings suggest that GhIRX15s participate in fiber xylan biosynthesis and modulate fiber development via forming large multiprotein complexes.展开更多
The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed...The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.展开更多
Occurrence of neurofibrillary tangles of the tau protein is a hallmark of tau-related neurodegenerative diseases, i.e. Alzheimer's disease(AD) and frontotemporal dementia. The pathological mechanism underlying AD ...Occurrence of neurofibrillary tangles of the tau protein is a hallmark of tau-related neurodegenerative diseases, i.e. Alzheimer's disease(AD) and frontotemporal dementia. The pathological mechanism underlying AD remains poorly understood, and effective treatments are still unavailable to mitigate the disease.Inhibiting of tau aggregation and disrupting the existing fibrils are key targets in drug discovery towards preventing or curing AD. In this study, grape seed proanthocyanidins(GSPs) was found to effectively inhibit the repeat domain of tau(tau-RD) aggregation and disaggregate tau-RD fibrils in a concentrationdependent manner by inhibiting β-sheet formation of tau-RD. In cells, GSPs relieved cytotoxicity induced by tau-RD aggregates. Molecular dynamics simulations indicated that strong hydrogen bonding,hydrophobic interaction and π-π stacking between GSPs and tau-RD protein were major reasons why GSPs had high inhibitory activity on tau-RD fibrillogenesis. These results provide preliminary data to develop GSPs into medicines, foodstuffs or nutritional supplements for AD patients, suggesting that GSPs could be a candidate molecule in the drug design for AD therapeutics.展开更多
Delayed passage of meconium or constipation during the perinatal period is traditionally regarded as a signal to initiate further work up to evaluate for serious diagnoses such as Hirschsprung’s disease(HD),meconium ...Delayed passage of meconium or constipation during the perinatal period is traditionally regarded as a signal to initiate further work up to evaluate for serious diagnoses such as Hirschsprung’s disease(HD),meconium ileus due to Cystic Fibrosis,etc.The diagnosis of HD particularly warrants invasive testing to confirm the diagnosis,such as anorectal manometry or rectal suction biopsy.What if there was another etiology of perinatal constipation,that is far lesser known?Cow’s milk protein allergy(CMPA)is often diagnosed in infants within the first few weeks of life,however,there are studies that show that the CMPA allergen can be passed from mother to an infant in-utero,therefore allowing symptoms to show as early as day one of life.The presentation is more atypical,with perinatal constipation rather than with bloody stools,diarrhea,and vomiting.The diagnosis and management would be avoidance of cow's milk protein within the diet,with results and symptom improvement in patients immediately.Therefore,we discuss whether an alternative pathway to address perinatal constipation should be further discussed and implemented to potentially avoid invasive techniques in patients.This entails first ruling out CMPA with safe,noninvasive techniques with diet modification,and if unsuccessful,then moving forward with further diagnostic modalities.展开更多
[Objectives] To investigate the effects of ginseng protein on gut microbiota and BDNF/TrkB signaling pathway in Alzheimer s disease (AD) mice. [Methods] D-galactose/AlCl 3 co-induction was used to establish AD model, ...[Objectives] To investigate the effects of ginseng protein on gut microbiota and BDNF/TrkB signaling pathway in Alzheimer s disease (AD) mice. [Methods] D-galactose/AlCl 3 co-induction was used to establish AD model, and mice were randomly divided into normal group 1, normal group 2, model group 1, model group 2, ginseng protein group, and microbiota transplantation group. Morris water maze experiment was used to evaluate learning and memory ability, and Western blot method was used to detect the expression of APP, p-Tau, BDNF, TrkB, p-TrkB proteins in brain tissue, and 16S rDNA was used to detect diversity of fecal microbiota. [Results] Ginseng protein and microbiota transplantation can shorten the escape latency of mice ( P <0.05), increase the number of crossing platforms ( P <0.05), reduce the expression of APP and p-Tau proteins in brain tissue ( P <0.05, P <0.01), increase the expression of BDNF, p-TrkB, p-TrkB/TrkB proteins ( P <0.05, P <0.01), and reduce the abundance of Alloprevotella, Ruminococcaceae _UCG-014, Prevotellaceae _UCG-001, and Ruminococcus _1 ( P <0.05, P <0.01). [Conclusions] The action mechanism of ginseng protein anti AD may be through regulating gut microbiota diversity and activating the BDNF/TrkB signaling pathway.展开更多
Objective To investigate the effects of 14-3-3 protein overexpression on the 1-methyl-4-phenylpyridinium （MPP^＋） induced pheochromocytoma （PC12） cell death and the potential mechanisms. Methods pcDNA3.1（＋）-14-...Objective To investigate the effects of 14-3-3 protein overexpression on the 1-methyl-4-phenylpyridinium （MPP^＋） induced pheochromocytoma （PC12） cell death and the potential mechanisms. Methods pcDNA3.1（＋）-14-3-3 plasmids, which could be expressed in mammalian cell, were constructed and transfected into PC 12 cells with Lipofectamine 2000. The expression of 14-3-3 protein, Bcl-2 protein, and BAD protein were determined by western blot. 3-（4,5- dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assay, microplate reader, and flow cytometric analysis were used to measure cell viability, the caspase activity, and apoptotic ratio respectively. Results （1） The expression of 14-3-3 protein increased significantly three weeks after pcDNA3.1（＋）-14-3-3 plasmids transfected into PC 12 cells. （2） MPP^＋ caused a decrease of cell viability in a dose-dependent manner. At 100μmol/L MPP^＋, cell viability reduced approximately 50%. （3） The caspase activity increased along with the MPP^＋ concentrations rising and reached its maximum value （0.34 μmol/mg protein） at 100 μmol/L MPP＊. However caspase activity decreased significantly when the MPP^＋ concentration exceeded 100 μmol/L. （4） Overexpression of 14-3-3 protein decreased the apoptosis ratio of PC 12 cells treated with 100μmol/L MPP^＋ from 26.5% to 8.6%. （5） Bcl-2 protein tended to decrease but BAD protein tended to increase after treatment of PC 12 cells with 100 μmol/L MPP^＋. Overexpression of 14-3-3 protein significantly increased the cellular level of Bcl-2 protein and decreased that of BAD protein. Conclusion Overexpression of 14-3-3 protein may reduce MPP^＋-induced apoptotic cell death in PC12 cells by up-regulating the Bcl-2 expression and down-regulating the BAD expression. These results may provide a promising target for treatment of Parkinson＇s disease.展开更多
Two major causes of human aging include protein misfolding and free radicals. Protein misfolding occurs when proteins which are synthesized by cells do not have the proper amino acid sequence or do not achieve the cor...Two major causes of human aging include protein misfolding and free radicals. Protein misfolding occurs when proteins which are synthesized by cells do not have the proper amino acid sequence or do not achieve the correct three-dimensional configuration to function properly. Peer-reviewed scientific literature explains how these processes contribute to many age-associated diseases. A few examples include cancer, heart disease, dementias including Parkinson’s and Alzheimer’s </span><span style="font-family:Verdana;">diseases, and arthritis. This article reviews how protein misfolding can be slowed and even reversed by appropriate nutrition, potentially slowing and reversing these diseases. One cause of misfolding is mRNA translation occurring too rapidly for proper chaperone binding or protein folding. A second cause is deficiency of amino acids so improper tRNA binding occurs. A third cause is free radicals. They cause mutations promoting misfolding and cancer, and oxidize lipoproteins causing plaque in circulation promoting heart disease and stroke. Nutrients with proven actions will contribute to longer healthspans for our aging population. Healthspan is the number of healthy years before chronic or terminal diseases substantially impair the quality of life. This can be done especially by slowing and reversing these three causes of PM. Niacin, quercetin, EGCG, alpha-lipoic acid, N-acetyl-carnitine, tyrosine and cysteine address protein misfolding. Vitamin C and glutathione trap free radicals. Vitamin K amplifies free radical cancer killing by vitamin C and activates decalcification enzymes which remove calcium deposits in the circulatory system and strengthen bones. Apigenin activates the pathway of caloric restriction and induces cancer cell apoptosis. This article provides citations and explanations of the progress showing new ways to maintain health as we age. For convenience and cost savings, many of these ingredients can be consumed in supplement form, taken twice a day to maintain water-soluble nutrient levels.展开更多
[Objective] ＂Tapping panel dryness （TPD）＂, a syndrome known as tapping incision blocked partly or entirely during latex exploiting, has become the most important factor causing great losses for rubber production. ...[Objective] ＂Tapping panel dryness （TPD）＂, a syndrome known as tapping incision blocked partly or entirely during latex exploiting, has become the most important factor causing great losses for rubber production. Aiming to elucidate the molecular mechanism of tapping panel dryness occurrence, this study carried out molecular cloning and bioinformatical analysis of a mRPL21 cDNA sequence, a gene associated with TPD. [Method] In a preliminary study, an expressed sequence tag （EST） encoding a deduced protein homologous to mitochondrial 50S ribosomal protein L21 （mRPL21）, which showed to be down-regulated in the latex of TPD-affected rubber trees, was isolated by suppression subtractive hybridization （SSH）. After ESTs assembling and RT-PCR validation, an 853 bp cDNA sequence with an open reading frame （ORF） was cloned, which was named as HbmRPL21 under GenBank accession number of HM230670. [Result] Bioinformatical analysis suggests that HbmRPL21 encodes a deduced polypeptide of 271 amino acids with a theoretical molecular weight （Mw） of 30.52 kDa and isolectric point （pI） of 8.40, and HbmRPL21 is a mitochondrion-targeted protein with a conserved domain of Ribosomal_L21p involving translation. Homology analysis reveals high amino acid sequence identity of mRPL21 from plants, while diversity of that between plant and animal kingdom. [Conclusion] This study laid the basis for further revealing the biological functions of mRPL21 in TPD-affected rubber trees.展开更多
Endoplasmic reticulum stress and mitochondrial dysfunction play important roles in Parkinson s disease,but the regulato ry mechanism remains elusive.Prohibitin-2(PHB2)is a newly discove red autophagy receptor in the m...Endoplasmic reticulum stress and mitochondrial dysfunction play important roles in Parkinson s disease,but the regulato ry mechanism remains elusive.Prohibitin-2(PHB2)is a newly discove red autophagy receptor in the mitochondrial inner membrane,and its role in Parkinson’s disease remains unclear.Protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)is a factor that regulates cell fate during endoplasmic reticulum stress.Parkin is regulated by PERK and is a target of the unfolded protein response.It is unclear whether PERK regulates PHB2-mediated mitophagy thro ugh Parkin.In this study,we established a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced mouse model of Parkinson’s disease.We used adeno-associated virus to knockdown PHB2 expression.Our res ults showed that loss of dopaminergic neurons and motor deficits were aggravated in the MPTP-induced mouse model of Parkinson’s disease.Ove rexpression of PHB2 inhibited these abnormalities.We also established a 1-methyl-4-phenylpyridine(MPP+)-induced SH-SY5Y cell model of Parkinson’s disease.We found that ove rexpression of Parkin increased co-localization of PHB2 and microtubule-associated protein 1 light chain 3,and promoted mitophagy.In addition,MPP+regulated Parkin involvement in PHB2-mediated mitophagy through phosphorylation of PERK.These findings suggest that PHB2 participates in the development of Parkinson’s disease by intera cting with endoplasmic reticulum stress and Parkin.展开更多
INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 a...INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer .展开更多
γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the ...γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general.展开更多
基金supported by the National Key R&D Program of China,No.2021YFF0702203(to HYL)the National Natural Science Foundation of China,No.82101323(to TS)Preferred Foundation of Zhejiang Postdoctors,No.ZJ2021152(to TS).
文摘Parkinson’s disease is a common neurodegenerative disorder that is associated with abnormal aggregation and accumulation of neurotoxic proteins,includingα-synuclein,amyloid-β,and tau,in addition to the impaired elimination of these neurotoxic protein.Atypical parkinsonism,which has the same clinical presentation and neuropathology as Parkinson’s disease,expands the disease landscape within the continuum of Parkinson’s disease and related disorders.The glymphatic system is a waste clearance system in the brain,which is responsible for eliminating the neurotoxic proteins from the interstitial fluid.Impairment of the glymphatic system has been proposed as a significant contributor to the development and progression of neurodegenerative disease,as it exacerbates the aggregation of neurotoxic proteins and deteriorates neuronal damage.Therefore,impairment of the glymphatic system could be considered as the final common pathway to neurodegeneration.Previous evidence has provided initial insights into the potential effect of the impaired glymphatic system on Parkinson’s disease and related disorders;however,many unanswered questions remain.This review aims to provide a comprehensive summary of the growing literature on the glymphatic system in Parkinson’s disease and related disorders.The focus of this review is on identifying the manifestations and mechanisms of interplay between the glymphatic system and neurotoxic proteins,including loss of polarization of aquaporin-4 in astrocytic endfeet,sleep and circadian rhythms,neuroinflammation,astrogliosis,and gliosis.This review further delves into the underlying pathophysiology of the glymphatic system in Parkinson’s disease and related disorders,and the potential implications of targeting the glymphatic system as a novel and promising therapeutic strategy.
基金supported by the National Natural Science Foundation of China(31970516 and 32372104)the Foundation of Hubei Hongshan Laboratory(2021hszd014).
文摘Cotton provides the most abundant natural fiber for the textile industry.The mature cotton fiber largely consists of secondary cell walls with the highest proportion of cellulose and a small amount of hemicellulose and lignin.To dissect the roles of hemicellulosic polysaccharides during fiber development,four IRREGULAR XYLEM 15(IRX15)genes,GhIRX15-1/-2/-3/-4,were functionally characterized in cotton.These genes encode DUF579 domain-containing proteins,which are homologs of AtIRX15 involved in xylan biosynthesis.The four GhIRX15 genes were predominantly expressed during fiber secondary wall thickening,and the encoded proteins were localized to the Golgi apparatus.Each GhIRX15 gene could restore the xylan deficient phenotype in the Arabidopsis irx15irx15l double mutant.Silencing of GhIRX15s in cotton resulted in shorter mature fibers with a thinner cell wall and reduced cellulose content as compared to the wild type.Intriguingly,GhIRX15-2 and GhIRX15-4 formed homodimers and heterodimers.In addition,the GhIRX15s showed physical interaction with glycosyltransferases GhGT43C,GhGT47A and GhGT47B,which are responsible for synthesis of the xylan backbone and reducing end sequence.Moreover,the GhIRX15s can form heterocomplexes with enzymes involved in xylan modification and side chain synthesis,such as GhGUX1/2,GhGXM1/2 and GhTBL1.These findings suggest that GhIRX15s participate in fiber xylan biosynthesis and modulate fiber development via forming large multiprotein complexes.
基金supported by the National Natural Science Foundation of China,Nos.91849115 and U1904207(to YX),81974211 and 82171247(to CS)Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences,No.2020-PT310-01(to YX).
文摘The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.
基金supported by the National Natural Science Foundation of China (21878262)。
文摘Occurrence of neurofibrillary tangles of the tau protein is a hallmark of tau-related neurodegenerative diseases, i.e. Alzheimer's disease(AD) and frontotemporal dementia. The pathological mechanism underlying AD remains poorly understood, and effective treatments are still unavailable to mitigate the disease.Inhibiting of tau aggregation and disrupting the existing fibrils are key targets in drug discovery towards preventing or curing AD. In this study, grape seed proanthocyanidins(GSPs) was found to effectively inhibit the repeat domain of tau(tau-RD) aggregation and disaggregate tau-RD fibrils in a concentrationdependent manner by inhibiting β-sheet formation of tau-RD. In cells, GSPs relieved cytotoxicity induced by tau-RD aggregates. Molecular dynamics simulations indicated that strong hydrogen bonding,hydrophobic interaction and π-π stacking between GSPs and tau-RD protein were major reasons why GSPs had high inhibitory activity on tau-RD fibrillogenesis. These results provide preliminary data to develop GSPs into medicines, foodstuffs or nutritional supplements for AD patients, suggesting that GSPs could be a candidate molecule in the drug design for AD therapeutics.
文摘Delayed passage of meconium or constipation during the perinatal period is traditionally regarded as a signal to initiate further work up to evaluate for serious diagnoses such as Hirschsprung’s disease(HD),meconium ileus due to Cystic Fibrosis,etc.The diagnosis of HD particularly warrants invasive testing to confirm the diagnosis,such as anorectal manometry or rectal suction biopsy.What if there was another etiology of perinatal constipation,that is far lesser known?Cow’s milk protein allergy(CMPA)is often diagnosed in infants within the first few weeks of life,however,there are studies that show that the CMPA allergen can be passed from mother to an infant in-utero,therefore allowing symptoms to show as early as day one of life.The presentation is more atypical,with perinatal constipation rather than with bloody stools,diarrhea,and vomiting.The diagnosis and management would be avoidance of cow's milk protein within the diet,with results and symptom improvement in patients immediately.Therefore,we discuss whether an alternative pathway to address perinatal constipation should be further discussed and implemented to potentially avoid invasive techniques in patients.This entails first ruling out CMPA with safe,noninvasive techniques with diet modification,and if unsuccessful,then moving forward with further diagnostic modalities.
基金Supported by Liaoning Province Science and Technology Department Project(20180530033,2022-MS-281)Liaoning Provincial Department of Education Project(LJKZZ20220105)Liaoning University of Traditional Chinese Medicine Project(2021LZY042).
文摘[Objectives] To investigate the effects of ginseng protein on gut microbiota and BDNF/TrkB signaling pathway in Alzheimer s disease (AD) mice. [Methods] D-galactose/AlCl 3 co-induction was used to establish AD model, and mice were randomly divided into normal group 1, normal group 2, model group 1, model group 2, ginseng protein group, and microbiota transplantation group. Morris water maze experiment was used to evaluate learning and memory ability, and Western blot method was used to detect the expression of APP, p-Tau, BDNF, TrkB, p-TrkB proteins in brain tissue, and 16S rDNA was used to detect diversity of fecal microbiota. [Results] Ginseng protein and microbiota transplantation can shorten the escape latency of mice ( P <0.05), increase the number of crossing platforms ( P <0.05), reduce the expression of APP and p-Tau proteins in brain tissue ( P <0.05, P <0.01), increase the expression of BDNF, p-TrkB, p-TrkB/TrkB proteins ( P <0.05, P <0.01), and reduce the abundance of Alloprevotella, Ruminococcaceae _UCG-014, Prevotellaceae _UCG-001, and Ruminococcus _1 ( P <0.05, P <0.01). [Conclusions] The action mechanism of ginseng protein anti AD may be through regulating gut microbiota diversity and activating the BDNF/TrkB signaling pathway.
基金supported by National Natural Science Foundation of China(No:30570627).
文摘Objective To investigate the effects of 14-3-3 protein overexpression on the 1-methyl-4-phenylpyridinium （MPP^＋） induced pheochromocytoma （PC12） cell death and the potential mechanisms. Methods pcDNA3.1（＋）-14-3-3 plasmids, which could be expressed in mammalian cell, were constructed and transfected into PC 12 cells with Lipofectamine 2000. The expression of 14-3-3 protein, Bcl-2 protein, and BAD protein were determined by western blot. 3-（4,5- dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assay, microplate reader, and flow cytometric analysis were used to measure cell viability, the caspase activity, and apoptotic ratio respectively. Results （1） The expression of 14-3-3 protein increased significantly three weeks after pcDNA3.1（＋）-14-3-3 plasmids transfected into PC 12 cells. （2） MPP^＋ caused a decrease of cell viability in a dose-dependent manner. At 100μmol/L MPP^＋, cell viability reduced approximately 50%. （3） The caspase activity increased along with the MPP^＋ concentrations rising and reached its maximum value （0.34 μmol/mg protein） at 100 μmol/L MPP＊. However caspase activity decreased significantly when the MPP^＋ concentration exceeded 100 μmol/L. （4） Overexpression of 14-3-3 protein decreased the apoptosis ratio of PC 12 cells treated with 100μmol/L MPP^＋ from 26.5% to 8.6%. （5） Bcl-2 protein tended to decrease but BAD protein tended to increase after treatment of PC 12 cells with 100 μmol/L MPP^＋. Overexpression of 14-3-3 protein significantly increased the cellular level of Bcl-2 protein and decreased that of BAD protein. Conclusion Overexpression of 14-3-3 protein may reduce MPP^＋-induced apoptotic cell death in PC12 cells by up-regulating the Bcl-2 expression and down-regulating the BAD expression. These results may provide a promising target for treatment of Parkinson＇s disease.
文摘Two major causes of human aging include protein misfolding and free radicals. Protein misfolding occurs when proteins which are synthesized by cells do not have the proper amino acid sequence or do not achieve the correct three-dimensional configuration to function properly. Peer-reviewed scientific literature explains how these processes contribute to many age-associated diseases. A few examples include cancer, heart disease, dementias including Parkinson’s and Alzheimer’s </span><span style="font-family:Verdana;">diseases, and arthritis. This article reviews how protein misfolding can be slowed and even reversed by appropriate nutrition, potentially slowing and reversing these diseases. One cause of misfolding is mRNA translation occurring too rapidly for proper chaperone binding or protein folding. A second cause is deficiency of amino acids so improper tRNA binding occurs. A third cause is free radicals. They cause mutations promoting misfolding and cancer, and oxidize lipoproteins causing plaque in circulation promoting heart disease and stroke. Nutrients with proven actions will contribute to longer healthspans for our aging population. Healthspan is the number of healthy years before chronic or terminal diseases substantially impair the quality of life. This can be done especially by slowing and reversing these three causes of PM. Niacin, quercetin, EGCG, alpha-lipoic acid, N-acetyl-carnitine, tyrosine and cysteine address protein misfolding. Vitamin C and glutathione trap free radicals. Vitamin K amplifies free radical cancer killing by vitamin C and activates decalcification enzymes which remove calcium deposits in the circulatory system and strengthen bones. Apigenin activates the pathway of caloric restriction and induces cancer cell apoptosis. This article provides citations and explanations of the progress showing new ways to maintain health as we age. For convenience and cost savings, many of these ingredients can be consumed in supplement form, taken twice a day to maintain water-soluble nutrient levels.
基金Supported by the Fundamental Research Funds for Rubber Research Institute, CATAS (1630022011014)Key Science and Technology Project of Hainan Province (90107)+1 种基金Basic Scientific Research Operational Fund for Central-level Public-interest Research Institutes (YWFZX2010-9)Special Fund for Science and Technology Research of Public Welfare Trades ( nyhyzx07-033-1)~~
文摘[Objective] ＂Tapping panel dryness （TPD）＂, a syndrome known as tapping incision blocked partly or entirely during latex exploiting, has become the most important factor causing great losses for rubber production. Aiming to elucidate the molecular mechanism of tapping panel dryness occurrence, this study carried out molecular cloning and bioinformatical analysis of a mRPL21 cDNA sequence, a gene associated with TPD. [Method] In a preliminary study, an expressed sequence tag （EST） encoding a deduced protein homologous to mitochondrial 50S ribosomal protein L21 （mRPL21）, which showed to be down-regulated in the latex of TPD-affected rubber trees, was isolated by suppression subtractive hybridization （SSH）. After ESTs assembling and RT-PCR validation, an 853 bp cDNA sequence with an open reading frame （ORF） was cloned, which was named as HbmRPL21 under GenBank accession number of HM230670. [Result] Bioinformatical analysis suggests that HbmRPL21 encodes a deduced polypeptide of 271 amino acids with a theoretical molecular weight （Mw） of 30.52 kDa and isolectric point （pI） of 8.40, and HbmRPL21 is a mitochondrion-targeted protein with a conserved domain of Ribosomal_L21p involving translation. Homology analysis reveals high amino acid sequence identity of mRPL21 from plants, while diversity of that between plant and animal kingdom. [Conclusion] This study laid the basis for further revealing the biological functions of mRPL21 in TPD-affected rubber trees.
基金supported by the Key Science and Technology Research of Henan Province,No.222102310351(to JW)Luoyang 2022 Medical and Health Guiding Science and Technology Plan Project,No.2022057Y(to JY)Henan Medical Science and Technology Research Program Province-Ministry Co-sponsorship,No.SBGJ202002099(to JY)。
文摘Endoplasmic reticulum stress and mitochondrial dysfunction play important roles in Parkinson s disease,but the regulato ry mechanism remains elusive.Prohibitin-2(PHB2)is a newly discove red autophagy receptor in the mitochondrial inner membrane,and its role in Parkinson’s disease remains unclear.Protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)is a factor that regulates cell fate during endoplasmic reticulum stress.Parkin is regulated by PERK and is a target of the unfolded protein response.It is unclear whether PERK regulates PHB2-mediated mitophagy thro ugh Parkin.In this study,we established a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced mouse model of Parkinson’s disease.We used adeno-associated virus to knockdown PHB2 expression.Our res ults showed that loss of dopaminergic neurons and motor deficits were aggravated in the MPTP-induced mouse model of Parkinson’s disease.Ove rexpression of PHB2 inhibited these abnormalities.We also established a 1-methyl-4-phenylpyridine(MPP+)-induced SH-SY5Y cell model of Parkinson’s disease.We found that ove rexpression of Parkin increased co-localization of PHB2 and microtubule-associated protein 1 light chain 3,and promoted mitophagy.In addition,MPP+regulated Parkin involvement in PHB2-mediated mitophagy through phosphorylation of PERK.These findings suggest that PHB2 participates in the development of Parkinson’s disease by intera cting with endoplasmic reticulum stress and Parkin.
基金Supported by the Medical Research Foundation of Guangdong Province,No.1997423
文摘INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer .
基金supported in part by Award 2121063 from National Science Foundation(to YM)AG66986 from the National Institutes of Health(to MSW).
文摘γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general.
