The development of breast cancer is a complex process that involves the participation of different factors.Several authors have demonstrated the overexpression of muscarinic acetylcholine receptors(mAChRs)in different...The development of breast cancer is a complex process that involves the participation of different factors.Several authors have demonstrated the overexpression of muscarinic acetylcholine receptors(mAChRs)in different tumor tissues and their role in the modulation of tumor biology,positioning them as therapeutic targets in cancer.The conventional treatment for breast cancer involves surgery,radiotherapy,and/or chemotherapy.The latter presents disadvantages such as limited specificity,the appearance of resistance to treatment and other side effects.To prevent these side effects,several schedules of drug administration,like metronomic therapy,have been developed.Metronomic therapy is a type of chemotherapy in which one or more drugs are administered at low concentrations repetitively.Recently,two chemotherapeutic agents usually used to treat breast cancer have been considered able to activate mAChRs.The combination of low concentrations of these chemotherapeutic agents with muscarinic agonists could be a useful option to be applied in breast cancer treatment,since this combination not only reduces tumor cell survival without affecting normal cells,but also decreases pathological neo-angiogenesis,the expression of drug extrusion proteins and the cancer stem cell fraction.In this review,we focus on the previous evidences that have positioned mAChRs as relevant therapeutic targets in breast cancer and analyze the effects of administering muscarinic agonists in combination with conventional chemotherapeutic agents in a metronomic schedule.展开更多
OBJECTIVE Abnormal striatal dopaminergic and glutamatergic neurotransmis⁃sion is central to the pathophysiology of schizo⁃phrenia.In this study,we investigated the roles of M4 receptor interplay with D1 signaling in s...OBJECTIVE Abnormal striatal dopaminergic and glutamatergic neurotransmis⁃sion is central to the pathophysiology of schizo⁃phrenia.In this study,we investigated the roles of M4 receptor interplay with D1 signaling in stria⁃tal neurotransmission that affect glutamatergic transmission to control the etiology of neuropsy⁃chiatric disorders.METHODS To study dorsal striatum(DS)region-specific neuronal and behav⁃ioral responses modulated by M4 receptors,we used clustered regularly interspaced short palin⁃dromic repeats-associated protein 9 technology to generate mice lacking M4 in the dorsal stria⁃tum(DS-M4-KD).The M4 positive allosteric modu⁃lator,VU0467154,were used to study the phar⁃macologically profiles with M4 receptor stimula⁃tion in WT mice.Oxotremorine M(Oxo-M),a no subtype-selective muscarinic agonist,was used to show that mAchRs activation,in order to dissect the particular function of M4,in DS-M4-KD mice.Open filed test and forced swim test were used to assess the change of psychiatric-like behav⁃iors.Western blotting and immunohistochemistry were used to detect protein levels of phosphory⁃lation site of dopamine-and cAMP-regulated phosphoprotein of 32 ku(DARPP-32).Whole-cell patch-clamp recording was used to assess M4-mediated cholinergic inhibition of glutamater⁃gic synaptic input transmission.RESULTS West⁃ern blotting and immunohistochemistry assay showed VU0467154(5 mg·kg-1,ip)promoted phosphorylation of DARPP-32 at Thr75,and atten⁃uated D1-dependent phosphorylation of DARPP-32 at Thr34 within the mouse DS.Consistently,the Oxo-M(4μg,icv)also increased DARPP-32 phosphorylation at site Thr75 to reversed phos⁃phorylation at site Thr34 in WT mice,but not in DS-M4-KD mice.In parallel with altered DARPP-32 responses,VU0467154 or Oxo-M evoked a psychological stress response and reversed D1-induced hyperlocomotion in mice in open field test and force swim tests.However,Oxo-M sup⁃pression of D1-depengdeng behavioral respons⁃es was impaired in DS-M4-KD mice.Whole-cell patch recording showed that VU0467154 or Oxo-M mediated endogenous cholinergic inhibition of miniature excitatory postsynaptic currents through M4 receptors,which in turn suppressed D1-depen⁃dent glutamatergic synaptic transmission in the DS.CONCLUSION This study provides evidence for the role of M4 receptors in regulation of dopa⁃mine/DARPP-32 signaling and glutamate respons⁃es in the DS,and therefore modulation of psychi⁃atric behaviors associated with D1 signaling.This results indicate the mechanisms of treatments targeting M4 in psychiatric disorders.展开更多
Background:Anisodine hydrobromide(AT3),an anti-cholinergic agent,could be delivered to the brain across the blood-brain barrier and has been used clinically for the treatment of cerebral ischemia/reperfusion injury.En...Background:Anisodine hydrobromide(AT3),an anti-cholinergic agent,could be delivered to the brain across the blood-brain barrier and has been used clinically for the treatment of cerebral ischemia/reperfusion injury.Endothelial dysfunction can be caused by hypoxia/reoxygenation(H/R)via oxidative stress and metabolic alterations.The present study investigated whether AT3 regulates the production of nitric oxide(NO)and reactive oxygen species(ROS),and the HIF-1αpathway via regulation of muscarinic acetylcholine receptors(mAChRs)in brain microvascular endothelial cells after H/R exposure.Methods:Under H/R conditions,hCMEC/D3 cerebral microvascular endothelial cells were treated with AT3.Specific inhibitors of M2-and M4-mAChRs were used to explore the mechanism by which AT3 influences oxidative stress in endothelial cells.Then,mAChRs expression was detected by western blotting and NO production was detected by Greiss reaction.The intracellular ROS level was measured using DCFH-DA probes.The expression of hypoxia-inducible transcription factor 1α(HIF-1α)was also detected.Results:While H/R induced the expression of M2-and M4-mAChRs,AT3 suppressed the H/R-upregulated M2-and M4-mAChRs.H/R also induced the production of NO,ROS,and apoptosis.AT3 and M4-mAChR inhibitors inhibited the H/R-induced production of NO and ROS and apoptosis.HIF-1αwas induced by H/R,but was suppressed by AT3.Conclusion:Thus,the in vitro evidence shows that AT3 protects against H/R injury in cerebral microvascular endothelial cells via inhibition of HIF-1α,NO and ROS,predominantly through the downregulation of M4-mAChR.The findings offer novel understandings regarding AT3-mediated attenuation of endothelial cell apoptosis and cerebral ischemia/reperfusion injury.展开更多
Due to the lack of effective treatments,advanced colorectal cancer(CRC)remains a leading cause of cancer death in the United States.Emerging evidence supports the observation that muscarinic receptor(MR)signaling play...Due to the lack of effective treatments,advanced colorectal cancer(CRC)remains a leading cause of cancer death in the United States.Emerging evidence supports the observation that muscarinic receptor(MR)signaling plays a critical role in growth and progression of CRC.MR activation by acetylcholine and bile acids results in transactivation of epidermal growth factor receptors(EGFR)and post-EGFR signal transduction that enhances cell proliferation,migration,and invasion.Here,the authors review recent progress in understanding the molecular mechanisms underlying MR-mediated CRC progression and its therapeutic implications.展开更多
AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor(mAChR) M1 in the eyes of guinea pigs.METHODS: Thirty guinea pigs(15-20 days old) ...AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor(mAChR) M1 in the eyes of guinea pigs.METHODS: Thirty guinea pigs(15-20 days old) were randomly divided into three groups(n=10/group). Animals in group I were raised in a completely closed carton with green flickering light illumination. Those in group II were kept in the open top closed carton under normal natural light. Guinea pigs were raised in a sight-widen cage under normal natural light in group III. The refractive status and axial length were measured before and after 8 weeks' illumination. Moreover, total RNA extracted from retinal, choroidal, and scleral tissues were determined by real-time reverse transcription polymerase chain reaction(RT-PCR). The expressions of the receptor M1 were also explored in the retina, choroid, and sclera using immunohistochemistry.RESULTS: There was a remarkable reduction in refractive error and increase in axial length after 8-weeks' green flickering light stimulation(P<0.001). The expression of M1 receptor mRNA in sclera and retina in myopia group were remarkably lower than that in group II and III(P<0.01). Significant reduced expression of M1 receptor stimulated by green flickering light in retina and sclera tissues were also observed(P<0.05). However, there was no M1 receptor expression in choroid in 3 groups.CONCLUSION: Myopia can be induced by 8 weeks' green flickering light exposure in the animal model. M1 receptor may be involved causally or protectively in myopia development.展开更多
Idiopathic pulmonary fibrosis is an untreatable lethal lung disease, which is related to the aberrant proliferation of fibroblasts. M<sub>3</sub> muscarinic acetylcholine receptor (M<sub>3</sub>...Idiopathic pulmonary fibrosis is an untreatable lethal lung disease, which is related to the aberrant proliferation of fibroblasts. M<sub>3</sub> muscarinic acetylcholine receptor (M<sub>3</sub>-mAChR) activation exerts proliferative effect on various kinds of cells. However, whether M<sub>3</sub>-mAChR inhibition has a protective effect on pulmonary fibrosis remains unexplored. A rat model of pulmonary fibrosis was established by intratracheal instillation of bleomycin. Darifenacin was used to block M<sub>3</sub>-mAChR. Histological changes were observed using Masson’s Trichrome and hematoxylin and eosin (HE) staining. Hydroxyproline was measured by Hydroxyproline detection kit. Transforming growth factor β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent assay (ELISA). In vitro, pulmonary fibroblasts were isolated from lungs of neonatal rat. After treatment, the cell viability, Hydroxyproline level was measured by MTT and Hydroxyproline detection kit respectively. The expression level of extracellular signal-regulated kinase (ERK), nuclear factor kappa-B (N-NF-κB), and microRNA-21 (miR-21) was detected by western blot or quantitative real-time PCR (qRT-PCR). Darifenacin relieved the fibrotic effects provoked by bleomycin. The expression level of hydroxyproline, TGF-β1 and TNF-α level was all downregulated after darifenacin treatment. In lung fibroblasts, darifenacin decreased cell viability and hydroxyproline level induced by bleomycin. Besides, phosphorylation-ERK and nuclear N-NF-κB protein level was downregulated, as well as miR-21 level. M<sub>3</sub>-mAChR antagonist darifenacin attenuates bleomycin-induced pulmonary fibrosis in rats, which may relate to the ERK/NF-κB/miRNA-21 signaling pathway.展开更多
Diarrhea is a prevalent gastrointestinal problem associated with fatal implications.It is a huge public health concern that requires better alternatives to current drugs.This study investigated the mechanisms involved...Diarrhea is a prevalent gastrointestinal problem associated with fatal implications.It is a huge public health concern that requires better alternatives to current drugs.This study investigated the mechanisms involved in the antidiarrheal activity of Anacardium occidentale(Ao) stem bark extract,a plant commonly used in the management of diarrhea in Nigeria.Methanolic stem bark extract of the plant was partitioned into three fractions:hexane fraction,ethyl acetate fraction(Ao EF) and methanol fraction.In vitro studies on the effect of these fractions on guinea pig ileum(GPI) strips,as well as the modulatory effect of Ao EF on standard agonists-and antagonists-induced GPI contraction and relaxation,revealed Ao EF as the most active fraction.In vivo studies to assess the effect of Ao EF on the dopaminergic,muscarinic,and serotonergic pathways were carried out using gastric emptying(GE) and gastrointestinal transit(GT) as experimental end points.Ao EF was subjected to GC-MS analysis,while the identified compounds were docked with the muscarinic acetylcholine receptor M3(CHRM3) using Autodock Vina.Results indicated that Ao EF inhibited GE and GT via inhibition of CHRM3.In addition,GC-MS analysis revealed the presence of 24 compounds in Ao EF,while docking indicated that octadecanoic acid 2-(2-hydroxylethoxy)ethyl ester exhibited the highest binding affinity to CHRM3.This study indicated that the antidiarrheal activity of Ao is through its antimotility effect via the inhibition of the muscarinic pathway.And since none of the identified compounds exhibited higher binding affinity to CHRM3 relative to loperamide,the antimotility activity of these phytoconstituents may be via synergism.展开更多
Cholinergic nerves are widely distributed throughout the human body and participate in various physiological activities,including sensory,motor,and visceral activities,through cholinergic signaling.Cholinergic signali...Cholinergic nerves are widely distributed throughout the human body and participate in various physiological activities,including sensory,motor,and visceral activities,through cholinergic signaling.Cholinergic signaling plays an important role in pancreatic exocrine secretion.A large number of studies have found that cholinergic signaling overstimulates pancreatic acinar cells through muscarinic receptors,participates in the onset of pancreatic diseases such as acute pancreatitis and chronic pancreatitis,and can also inhibit the progression of pancreatic cancer.However,cholinergic signaling plays a role in reducing pain and inflammation through nicotinic receptors,but enhances the proliferation and invasion of pancreatic tumor cells.This review focuses on the progression of cholinergic signaling and pancreatic diseases in recent years and reveals the role of cholinergic signaling in pancreatic diseases.展开更多
Tropane alkaloids(TAs)are among the most valued chemical compounds known since pre-historic times.Poisonous plants from Solanaceae family(Hyoscyamus niger,Datura,Atropa belladonna,Scopolia lurida,Mandragora officinaru...Tropane alkaloids(TAs)are among the most valued chemical compounds known since pre-historic times.Poisonous plants from Solanaceae family(Hyoscyamus niger,Datura,Atropa belladonna,Scopolia lurida,Mandragora officinarum,Duboisia)and Erythroxylaceae(Erythroxylum coca)are rich sources of tropane alkaloids.These compounds possess the anticholinergic properties as they could block the neurotransmitter acetylcholine action in the central and peripheral nervous system by binding at either muscarinic and/or nicotinic receptors.Hence,they are of great clinical impor-tance and are used as antiemetics,anesthetics,antispasmodics,bronchodilator and mydriatics.They also serve as the lead compounds to generate more effective drugs.Due to the important pharmacological action they are listed in the WHO list of essential medicines and are available in market with FDA approval.However,being anticholinergic in action,TA medication are under the suspicion of causing dementia and cognitive decline like other medications with anticholinergic action,interestingly which is incorrect.There are published reviews on chemistry,biosynthesis,phar-macology,safety concerns,biotechnological aspects of TAs but the detailed information on anticholinergic mecha-nism of action,clinical pharmacology,FDA approval and anticholinergic burden is lacking.Hence the present review tries to fill this lacuna by critically summarizing and discussing the above mentioned aspects.展开更多
During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their el...During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening.We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse consolidation.The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this process.In particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental competition.The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific endings.We describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals.The downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary synapses.Finally,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to reduce transmitter release and promote withdrawal of the most unfavorable nerve terminals during elimination(the weakest in acetylcholine release and those that have already become silent).The main findings contribute to a better understanding of punishment-rewarding interactions between nerve endings during development.Identifying the molecular targets and signaling pathways that allow synapse consolidation or withdrawal of synapses in different situations is important for potential therapies in neurodegenerative diseases.展开更多
文摘The development of breast cancer is a complex process that involves the participation of different factors.Several authors have demonstrated the overexpression of muscarinic acetylcholine receptors(mAChRs)in different tumor tissues and their role in the modulation of tumor biology,positioning them as therapeutic targets in cancer.The conventional treatment for breast cancer involves surgery,radiotherapy,and/or chemotherapy.The latter presents disadvantages such as limited specificity,the appearance of resistance to treatment and other side effects.To prevent these side effects,several schedules of drug administration,like metronomic therapy,have been developed.Metronomic therapy is a type of chemotherapy in which one or more drugs are administered at low concentrations repetitively.Recently,two chemotherapeutic agents usually used to treat breast cancer have been considered able to activate mAChRs.The combination of low concentrations of these chemotherapeutic agents with muscarinic agonists could be a useful option to be applied in breast cancer treatment,since this combination not only reduces tumor cell survival without affecting normal cells,but also decreases pathological neo-angiogenesis,the expression of drug extrusion proteins and the cancer stem cell fraction.In this review,we focus on the previous evidences that have positioned mAChRs as relevant therapeutic targets in breast cancer and analyze the effects of administering muscarinic agonists in combination with conventional chemotherapeutic agents in a metronomic schedule.
文摘OBJECTIVE Abnormal striatal dopaminergic and glutamatergic neurotransmis⁃sion is central to the pathophysiology of schizo⁃phrenia.In this study,we investigated the roles of M4 receptor interplay with D1 signaling in stria⁃tal neurotransmission that affect glutamatergic transmission to control the etiology of neuropsy⁃chiatric disorders.METHODS To study dorsal striatum(DS)region-specific neuronal and behav⁃ioral responses modulated by M4 receptors,we used clustered regularly interspaced short palin⁃dromic repeats-associated protein 9 technology to generate mice lacking M4 in the dorsal stria⁃tum(DS-M4-KD).The M4 positive allosteric modu⁃lator,VU0467154,were used to study the phar⁃macologically profiles with M4 receptor stimula⁃tion in WT mice.Oxotremorine M(Oxo-M),a no subtype-selective muscarinic agonist,was used to show that mAchRs activation,in order to dissect the particular function of M4,in DS-M4-KD mice.Open filed test and forced swim test were used to assess the change of psychiatric-like behav⁃iors.Western blotting and immunohistochemistry were used to detect protein levels of phosphory⁃lation site of dopamine-and cAMP-regulated phosphoprotein of 32 ku(DARPP-32).Whole-cell patch-clamp recording was used to assess M4-mediated cholinergic inhibition of glutamater⁃gic synaptic input transmission.RESULTS West⁃ern blotting and immunohistochemistry assay showed VU0467154(5 mg·kg-1,ip)promoted phosphorylation of DARPP-32 at Thr75,and atten⁃uated D1-dependent phosphorylation of DARPP-32 at Thr34 within the mouse DS.Consistently,the Oxo-M(4μg,icv)also increased DARPP-32 phosphorylation at site Thr75 to reversed phos⁃phorylation at site Thr34 in WT mice,but not in DS-M4-KD mice.In parallel with altered DARPP-32 responses,VU0467154 or Oxo-M evoked a psychological stress response and reversed D1-induced hyperlocomotion in mice in open field test and force swim tests.However,Oxo-M sup⁃pression of D1-depengdeng behavioral respons⁃es was impaired in DS-M4-KD mice.Whole-cell patch recording showed that VU0467154 or Oxo-M mediated endogenous cholinergic inhibition of miniature excitatory postsynaptic currents through M4 receptors,which in turn suppressed D1-depen⁃dent glutamatergic synaptic transmission in the DS.CONCLUSION This study provides evidence for the role of M4 receptors in regulation of dopa⁃mine/DARPP-32 signaling and glutamate respons⁃es in the DS,and therefore modulation of psychi⁃atric behaviors associated with D1 signaling.This results indicate the mechanisms of treatments targeting M4 in psychiatric disorders.
基金funding from the National Natural Science Foundation of China(12272246)the Key Research and Development Projects of Sichuan Province(2023YFS0075).
文摘Background:Anisodine hydrobromide(AT3),an anti-cholinergic agent,could be delivered to the brain across the blood-brain barrier and has been used clinically for the treatment of cerebral ischemia/reperfusion injury.Endothelial dysfunction can be caused by hypoxia/reoxygenation(H/R)via oxidative stress and metabolic alterations.The present study investigated whether AT3 regulates the production of nitric oxide(NO)and reactive oxygen species(ROS),and the HIF-1αpathway via regulation of muscarinic acetylcholine receptors(mAChRs)in brain microvascular endothelial cells after H/R exposure.Methods:Under H/R conditions,hCMEC/D3 cerebral microvascular endothelial cells were treated with AT3.Specific inhibitors of M2-and M4-mAChRs were used to explore the mechanism by which AT3 influences oxidative stress in endothelial cells.Then,mAChRs expression was detected by western blotting and NO production was detected by Greiss reaction.The intracellular ROS level was measured using DCFH-DA probes.The expression of hypoxia-inducible transcription factor 1α(HIF-1α)was also detected.Results:While H/R induced the expression of M2-and M4-mAChRs,AT3 suppressed the H/R-upregulated M2-and M4-mAChRs.H/R also induced the production of NO,ROS,and apoptosis.AT3 and M4-mAChR inhibitors inhibited the H/R-induced production of NO and ROS and apoptosis.HIF-1αwas induced by H/R,but was suppressed by AT3.Conclusion:Thus,the in vitro evidence shows that AT3 protects against H/R injury in cerebral microvascular endothelial cells via inhibition of HIF-1α,NO and ROS,predominantly through the downregulation of M4-mAChR.The findings offer novel understandings regarding AT3-mediated attenuation of endothelial cell apoptosis and cerebral ischemia/reperfusion injury.
基金support and sponsorship This work was supported by Merit Review Awards from the United States Department of Veterans Affairs Program(G.Xie and J.P.Raufman)NIH R21-DK093406 and T32 DK067872(J.P.Raufman).
文摘Due to the lack of effective treatments,advanced colorectal cancer(CRC)remains a leading cause of cancer death in the United States.Emerging evidence supports the observation that muscarinic receptor(MR)signaling plays a critical role in growth and progression of CRC.MR activation by acetylcholine and bile acids results in transactivation of epidermal growth factor receptors(EGFR)and post-EGFR signal transduction that enhances cell proliferation,migration,and invasion.Here,the authors review recent progress in understanding the molecular mechanisms underlying MR-mediated CRC progression and its therapeutic implications.
基金Supported by Qilu Hospital of Shandong University (No.201805049)
文摘AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor(mAChR) M1 in the eyes of guinea pigs.METHODS: Thirty guinea pigs(15-20 days old) were randomly divided into three groups(n=10/group). Animals in group I were raised in a completely closed carton with green flickering light illumination. Those in group II were kept in the open top closed carton under normal natural light. Guinea pigs were raised in a sight-widen cage under normal natural light in group III. The refractive status and axial length were measured before and after 8 weeks' illumination. Moreover, total RNA extracted from retinal, choroidal, and scleral tissues were determined by real-time reverse transcription polymerase chain reaction(RT-PCR). The expressions of the receptor M1 were also explored in the retina, choroid, and sclera using immunohistochemistry.RESULTS: There was a remarkable reduction in refractive error and increase in axial length after 8-weeks' green flickering light stimulation(P<0.001). The expression of M1 receptor mRNA in sclera and retina in myopia group were remarkably lower than that in group II and III(P<0.01). Significant reduced expression of M1 receptor stimulated by green flickering light in retina and sclera tissues were also observed(P<0.05). However, there was no M1 receptor expression in choroid in 3 groups.CONCLUSION: Myopia can be induced by 8 weeks' green flickering light exposure in the animal model. M1 receptor may be involved causally or protectively in myopia development.
文摘Idiopathic pulmonary fibrosis is an untreatable lethal lung disease, which is related to the aberrant proliferation of fibroblasts. M<sub>3</sub> muscarinic acetylcholine receptor (M<sub>3</sub>-mAChR) activation exerts proliferative effect on various kinds of cells. However, whether M<sub>3</sub>-mAChR inhibition has a protective effect on pulmonary fibrosis remains unexplored. A rat model of pulmonary fibrosis was established by intratracheal instillation of bleomycin. Darifenacin was used to block M<sub>3</sub>-mAChR. Histological changes were observed using Masson’s Trichrome and hematoxylin and eosin (HE) staining. Hydroxyproline was measured by Hydroxyproline detection kit. Transforming growth factor β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent assay (ELISA). In vitro, pulmonary fibroblasts were isolated from lungs of neonatal rat. After treatment, the cell viability, Hydroxyproline level was measured by MTT and Hydroxyproline detection kit respectively. The expression level of extracellular signal-regulated kinase (ERK), nuclear factor kappa-B (N-NF-κB), and microRNA-21 (miR-21) was detected by western blot or quantitative real-time PCR (qRT-PCR). Darifenacin relieved the fibrotic effects provoked by bleomycin. The expression level of hydroxyproline, TGF-β1 and TNF-α level was all downregulated after darifenacin treatment. In lung fibroblasts, darifenacin decreased cell viability and hydroxyproline level induced by bleomycin. Besides, phosphorylation-ERK and nuclear N-NF-κB protein level was downregulated, as well as miR-21 level. M<sub>3</sub>-mAChR antagonist darifenacin attenuates bleomycin-induced pulmonary fibrosis in rats, which may relate to the ERK/NF-κB/miRNA-21 signaling pathway.
文摘Diarrhea is a prevalent gastrointestinal problem associated with fatal implications.It is a huge public health concern that requires better alternatives to current drugs.This study investigated the mechanisms involved in the antidiarrheal activity of Anacardium occidentale(Ao) stem bark extract,a plant commonly used in the management of diarrhea in Nigeria.Methanolic stem bark extract of the plant was partitioned into three fractions:hexane fraction,ethyl acetate fraction(Ao EF) and methanol fraction.In vitro studies on the effect of these fractions on guinea pig ileum(GPI) strips,as well as the modulatory effect of Ao EF on standard agonists-and antagonists-induced GPI contraction and relaxation,revealed Ao EF as the most active fraction.In vivo studies to assess the effect of Ao EF on the dopaminergic,muscarinic,and serotonergic pathways were carried out using gastric emptying(GE) and gastrointestinal transit(GT) as experimental end points.Ao EF was subjected to GC-MS analysis,while the identified compounds were docked with the muscarinic acetylcholine receptor M3(CHRM3) using Autodock Vina.Results indicated that Ao EF inhibited GE and GT via inhibition of CHRM3.In addition,GC-MS analysis revealed the presence of 24 compounds in Ao EF,while docking indicated that octadecanoic acid 2-(2-hydroxylethoxy)ethyl ester exhibited the highest binding affinity to CHRM3.This study indicated that the antidiarrheal activity of Ao is through its antimotility effect via the inhibition of the muscarinic pathway.And since none of the identified compounds exhibited higher binding affinity to CHRM3 relative to loperamide,the antimotility activity of these phytoconstituents may be via synergism.
基金Supported by National Natural Science Foundation of China,No.82100686.
文摘Cholinergic nerves are widely distributed throughout the human body and participate in various physiological activities,including sensory,motor,and visceral activities,through cholinergic signaling.Cholinergic signaling plays an important role in pancreatic exocrine secretion.A large number of studies have found that cholinergic signaling overstimulates pancreatic acinar cells through muscarinic receptors,participates in the onset of pancreatic diseases such as acute pancreatitis and chronic pancreatitis,and can also inhibit the progression of pancreatic cancer.However,cholinergic signaling plays a role in reducing pain and inflammation through nicotinic receptors,but enhances the proliferation and invasion of pancreatic tumor cells.This review focuses on the progression of cholinergic signaling and pancreatic diseases in recent years and reveals the role of cholinergic signaling in pancreatic diseases.
基金funded by the National Research Foundation of Korea and by the Korean Government (2020R1A2B5B01002463 and 2021R1A6A1A03038996).
文摘Tropane alkaloids(TAs)are among the most valued chemical compounds known since pre-historic times.Poisonous plants from Solanaceae family(Hyoscyamus niger,Datura,Atropa belladonna,Scopolia lurida,Mandragora officinarum,Duboisia)and Erythroxylaceae(Erythroxylum coca)are rich sources of tropane alkaloids.These compounds possess the anticholinergic properties as they could block the neurotransmitter acetylcholine action in the central and peripheral nervous system by binding at either muscarinic and/or nicotinic receptors.Hence,they are of great clinical impor-tance and are used as antiemetics,anesthetics,antispasmodics,bronchodilator and mydriatics.They also serve as the lead compounds to generate more effective drugs.Due to the important pharmacological action they are listed in the WHO list of essential medicines and are available in market with FDA approval.However,being anticholinergic in action,TA medication are under the suspicion of causing dementia and cognitive decline like other medications with anticholinergic action,interestingly which is incorrect.There are published reviews on chemistry,biosynthesis,phar-macology,safety concerns,biotechnological aspects of TAs but the detailed information on anticholinergic mecha-nism of action,clinical pharmacology,FDA approval and anticholinergic burden is lacking.Hence the present review tries to fill this lacuna by critically summarizing and discussing the above mentioned aspects.
基金supported by Catalan Government,Nos.2014SGR344(to JT),2017SGR704(to JT),2021SGR01214(to MAL)MCIN/AEI/10.13039/501100011033/by“ERDF A way of making Europe,”Nos.SAF2015-67143(to JT),PID2019-106332GB-I00(to JT and MAL)and PID2022-141252NB-I00(to MAL).
文摘During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening.We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse consolidation.The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this process.In particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental competition.The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific endings.We describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals.The downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary synapses.Finally,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to reduce transmitter release and promote withdrawal of the most unfavorable nerve terminals during elimination(the weakest in acetylcholine release and those that have already become silent).The main findings contribute to a better understanding of punishment-rewarding interactions between nerve endings during development.Identifying the molecular targets and signaling pathways that allow synapse consolidation or withdrawal of synapses in different situations is important for potential therapies in neurodegenerative diseases.
