Exploring the interaction between the gut microbiota and cyclic adenosine monophosphate-protein kinase A signaling pathway:a potential therapeutic approach for neurodegenerative diseases

The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enhances communication along the gut–brain axis.The gut microbiota influences the cAMP-PKA signaling pathway through its metabolites,which activates the vagus nerve and modulates the immune and neuroendocrine systems.Conversely,alterations in the cAMP-PKA signaling pathway can affect the composition of the gut microbiota,creating a dynamic network of microbial-host interactions.This reciprocal regulation affects neurodevelopment,neurotransmitter control,and behavioral traits,thus playing a role in the modulation of neurological diseases.The coordinated activity of the gut microbiota and the cAMP-PKA signaling pathway regulates processes such as amyloid-β protein aggregation,mitochondrial dysfunction,abnormal energy metabolism,microglial activation,oxidative stress,and neurotransmitter release,which collectively influence the onset and progression of neurological diseases.This study explores the complex interplay between the gut microbiota and cAMP-PKA signaling pathway,along with its implications for potential therapeutic interventions in neurological diseases.Recent pharmacological research has shown that restoring the balance between gut flora and cAMP-PKA signaling pathway may improve outcomes in neurodegenerative diseases and emotional disorders.This can be achieved through various methods such as dietary modifications,probiotic supplements,Chinese herbal extracts,combinations of Chinese herbs,and innovative dosage forms.These findings suggest that regulating the gut microbiota and cAMP-PKA signaling pathway may provide valuable evidence for developing novel therapeutic approaches for neurodegenerative diseases.

Metformin promotes angiogenesis and functional recovery in aged mice after spinal cord injury by adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway

Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.

AB015.Metabolic stress in glaucoma engages early activation of the energy biosensor adenosine monophosphate-activated protein kinase leading to neuronal dysfunction

Background:Metabolic stress has been proposed to contribute to neuronal damage in glaucoma,but the mechanism driving this response is not understood.The adenosine monophosphate-activated protein kinase(AMPK)is a master regulator of energy homeostasis that becomes active at the onset of energy stress.AMPK is a potent inhibitor of the mammalian target of rapamycin complex 1(mTORC1),which we showed is essential for the maintenance of retinal ganglion cell(RGC)dendrites,synapses,and survival.Here,we tested the hypothesis that AMPK is an early mediator of metabolic stress in glaucoma.Methods:Unilateral elevation of intraocular pressure was induced by injection of magnetic microbeads into the anterior chamber of mice expressing yellow fluorescent protein in RGCs.Inhibition of AMPK was achieved by administration of siRNA or compound C.RGC dendritic trees were 3D-reconstructed and analyzed with Imaris(Bitplane),and survival was assessed by counting Brn3a or RBPMS-labeled soma and axons in the optic nerve.RGC function was examined by quantification of anterograde axonal transport after intraocular administration of cholera toxinβ-subunit.Retinas from glaucoma patients were analyzed for expression of active AMPK.Results:Ocular hypertension triggered rapid upregulation of AMPK activity in RGCs concomitant with loss of mTORC1 function.AMPK inhibition with compound C or siRNA effectively restored mTORC1 activity and promoted an increase in total dendritic length,surface and complexity relative to control retinas.Attenuation of AMPK activity led to robust RGC soma and axon survival.For example,95%of RGCs(2,983±258 RGCs/mm2,mean±S.E.M.)survived with compound C compared to 77%in vehicle-treated eyes(2,430±233 RGCs/mm2)(ANOVA,P<0.001)at three weeks after glaucoma induction(n=8-10/group).Importantly,blockade of AMPK activity effectively restored anterograde axonal transport.Lastly,RGC-specific upregulation of AMPK activity was detected in human glaucomatous retinas relative to age-matched controls(n=10/group).Conclusions:Metabolic stress in glaucoma involves AMPK activation and mTORC1 inhibition promoting early RGC dendritic pathology,dysfunction and neurodegeneration.

Gypenoside ameliorates insulin resistance and hyperglycemia via the AMPK-mediated signaling pathways in the liver of type 2 diabetes mellitus mice

Gynostemma pentaphyllum,also called"Southern Ginseng"in China,is a traditional Asian folk medicinal plant.Gypenosides(Gps)are the biologically active constituents of G.pentaphyllum,which have been reported with hypoglycemic activity.However,the underlying mechanisms are unclear.The effects of two Gps(Gp-Ⅰand Gp-Ⅱ)on type 2 diabetic mellitus(T2DM)mice,induced by high-fat and high-sugar diet and streptozotocin,were evaluated to explore the mechanism of their hypoglycemic actions.Gps reduced fasting blood glucose and serum lipids,as well as significantly improved T2DM mice glucose tolerance and insulin resistance(IR).After Gps treatment,the severity of liver injury was reduced and liver glycogen content increased.In addition,Gps promoted the phosphorylation of adenosine monophosphate-activated protein kinase(AMPK),and downregulated the key proteins phosphoenolpyruvate carboxy kinase and glucose-6 phosphatase,in the AMPK signaling pathway.Thus,our study suggests that Gps mediate hepatic gluconeogenesis and improve IR via activating AMPK signaling pathway in T2DM mice.

Adenosine triphosphate promotes locomotor recovery after spinal cord injury by activating mammalian target of rapamycin pathway in rats

The mammalian target of rapamycin （mTOR） pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord injury, rat models of spinal cord injury were established by modified Allen＇s stall method and interfered for 7 days by intraperitoneal administration of mTOR activator adenosine triphosphate and mTOR kinase inhibitor rapamycin. At 1-4 weeks after spinal cord injury induction, the Basso, Beattie and Bresnahan locomotor rating scale was used to evaluate rat locomotor function, and immunohistochemical staining and western blot analysis were used to detect the expression of nestin （neural stem cell marker）, neuronal nuclei （neuronal marker）, neuron specific enolase, neurofilament protein 200 （axonal marker）, glial fibrillary acidic protein （astrocyte marker）, Akt, mTOR and signal transduction and activator of transcription 3 （STAT3）. Results showed that adenosine triphosphate-mediated Akt/mTOR/STAT3 pathway increased endogenous neural stem cells, induced neurogenesis and axonal growth, inhibited excessive astrogliosis and improved the locomotor function of rats with spinal cord injury.

Effects of Ginsenoside Rb1 on Skeletal Muscle Insulin Resistance and Adenosine Monophosphate?activated Protein Kinase Signaling Pathway in Obese Mice

Objectives: The objective of the study is to observe the effects of ginsenoside Rb1 on indexes of body weight, body composition, blood lipid, skeletal muscle endurance, and insulin sensitivity in obese mice, probe into its pharmacological action, and further explore its effects on adenosine monophosphate-activated protein kinase(AMPK) signaling pathway in skeletal muscle. Materials and Methods: Eight-week-old C57 BL/6 J mice were fed with high-fat diet for 12 weeks to establish obese mouse model. The model-establishment obese mice were randomly divided into three groups including model control group, metformin group, and ginsenoside Rb1 group. In the normal control group, normal diet was administered. The intervention period was 8 weeks. Body weight and food intake of the mice were measured regularly every week. The treadmill test was performed at weeks 3 and 7, and the oral glucose tolerance test was carried out at weeks 4 and 8. Body composition of the mice was detected by applying NMR Animal Body Composition Analyzer at week 8. Four parameters of blood lipids and free fatty acid(FFA)levels were detected. The m RNA expression of AMPKα and proliferator-activated receptor gamma coactivator-1α(PGC-1α) in skeletal muscle was examined by real-time fluorescence quantitative polymerase chain reaction, and the influence of ginsenoside Rb1 on protein expression of AMPKα, p-AMPKα, and PGC-1α was observed by western blotting. Results: The body weight(since the 5 th week of drug administration)and food intake of the mice in the ginsenoside Rb1 group were significantly lower than those in the model control group(P < 0.05) in a time-dependent manner. Ginsenoside Rb1 could significantly reduce the levels of triglyceride and low-density lipoprotein cholesterol, while increase the high-density lipoprotein cholesterol level(P < 0.05). In addition, ginsenoside Rb1 could reduce the serum FFA level(P < 0.05).After the administration of ginsenoside Rb1 for 8 weeks, the body fat mass of obese mice decreased and the lean mass increased(P < 0.05).The skeletal muscle endurance and the oral glucose tolerance of the obese mice improved using ginsenoside Rb1. At the molecular level,ginsenoside Rb1 could up-regulate the mRNA and protein expression of AMPKα in skeletal muscle, and increase the content of p-AMPK protein significantly(P < 0.01). At the same time, the mRNA and protein level of PGC-1α was also un-regulated, correspondingly(P < 0.01).Conclusion: Ginsenoside Rb1 exerts effects on reducing body weight, decreasing blood lipid levels, enhancing the skeletal muscle endurance,and increasing the insulin sensitivity in obese mice by activating the related proteins in AMPK signaling pathway in skeletal muscle.

Antidepressant effect of electroacupuncture regulates signal targeting in the brain and increases brain- derived neurotrophic factor levels

Electroacupuncture improves depressive behavior faster and with fewer adverse effects than antidepressant medication. However, the antidepressant mechanism of electroacupuncture remains poorly understood. Here, we established a rat model of chronic unpredicted mild stress, and then treated these rats with electroacupuncture at Yintang （EX-HN3） and Baihui （DU20） with sparse waves at 2 Hz and 0.6 mA for 30 minutes, once a day. We found increased horizontal and vertical activity, and decreased immobility time, at 2 and 4 weeks after treatment. Moreover, levels of neurotransmitters （5-hydroxytryptamine, glutamate, and y-aminobutyric acid） and protein levels of brain-derived neurotrophic factor and brain-derived neurotrophic factor-related proteins （TrkB, protein kinase A, and phosphorylation of cyclic adenosine monophosphate response element binding protein） were increased in the hippocampus. Similarly, protein kinase A and TrkB mRNA levels were increased, and calcium-calmodulin-dependent protein kinase lI levels decreased. These findings suggest that electroacupuncture increases phosphorylation of cyclic adenosine monophosphate response element binding protein and brain-derived neurotrophic factor levels by regulating multiple targets in the cyclic adenosine rnonophosphate response element binding protein signal- ing pathway, thereby promoting nerve regeneration, and exerting an antidepressive effect.

Fusobacterium nucleatum-induced imbalance in microbiome-derived butyric acid levels promotes the occurrence and development of colorectal cancer

BACKGROUND Colorectal cancer(CRC)ranks among the most prevalent malignant tumors globally.Recent reports suggest that Fusobacterium nucleatum(F.nucleatum)contributes to the initiation,progression,and prognosis of CRC.Butyrate,a short-chain fatty acid derived from the bacterial fermentation of soluble dietary fiber,is known to inhibit various cancers.This study is designed to explore whether F.nucleatum influences the onset and progression of CRC by impacting the intestinal metabolite butyric acid.AIM To investigate the mechanism by which F.nucleatum affects CRC occurrence and development.METHODS Alterations in the gut microbiota of BALB/c mice were observed following the oral administration of F.nucleatum.Additionally,DLD-1 and HCT116 cell lines were exposed to sodium butyrate(NaB)and F.nucleatum in vitro to examine the effects on proliferative proteins and mitochondrial function.RESULTS Our research indicates that the prevalence of F.nucleatum in fecal samples from CRC patients is significantly greater than in healthy counterparts,while the prevalence of butyrate-producing bacteria is notably lower.In mice colonized with F.nucleatum,the population of butyrate-producing bacteria decreased,resulting in altered levels of butyric acid,a key intestinal metabolite of butyrate.Exposure to NaB can impair mitochondrial morphology and diminish mitochondrial membrane potential in DLD-1 and HCT116 CRC cells.Consequently,this leads to modulated production of adenosine triphosphate and reactive oxygen species,thereby inhibiting cancer cell prolif-eration.Additionally,NaB triggers the adenosine monophosphate-activated protein kinase(AMPK)signaling pathway,blocks the cell cycle in HCT116 and DLD-1 cells,and curtails the proliferation of CRC cells.The combined presence of F.nucleatum and NaB attenuated the effects of the latter.By employing small interfering RNA to suppress AMPK,it was demonstrated that AMPK is essential for NaB’s inhibition of CRC cell proliferation.CONCLUSION F.nucleatum can promote cancer progression through its inhibitory effect on butyric acid,via the AMPK signaling pathway.

Hypoglycemic effect and the mechanism of action of a polysaccharide from sweet corncob in a high-fat diet and streptozotocin-induced diabetic mice

Type 2 diabetes mellitus(T2DM)is a metabolic disease caused by a glycolipid metabolism disorder and isletβ-cell dysfunction.SCP-80-I is a biologically active water-soluble polysaccharide isolated from sweet corncob,an agricultural byproduct.The hypoglycemic effects of SCP-80-I on T2DM mice and its mechanisms were investigated in this study.SCP-80-I was found to significantly reduce blood glucose and lipid deposition levels in T2DM mice,as well as decrease serum leptin and increase adiponectin secretion.Interestingly,real time-polymerase chain reaction(RT-PCR)and Western blotting results revealed that SCP-80-I could regulate the expression of several glycolipid metabolisms and insulin secretion genes and proteins,including 5'-AMP-activated protein kinase(AMPK),carnitine palmitoyltransferase I(CPTI),and acetyl coenzyme A carboxylase(ACC)in the liver and AMPK,sirtuin1(Sirtl),peroxisome proliferator-activated receptorycoactivator-1(PGC-1α),and uncoupling protein 2(UCP2)in the pancreas.To have a hypoglycemic effect,SCP-80-1 regulated glycolipid metabolism and islet cell function in the liver by regulating the AMPK/AC C/CPT1 signaling pathway and the AMPK/Sirt1/PGC-1αand AMPK/Sirtl/UCP2 signaling pathways.These findings improve our understanding of polysaccharides derived from sweet corncob and the use of SCP-80-I in the production of hypoglycemic foods.

基于AMPK信号通路改善T2DM胰岛素抵抗中药有效成分研究进展

胰岛素抵抗(IR)是2型糖尿病(T2DM)的重要病理生理机制,对IR的治疗成为防治T2DM的关键。IR是指胰岛素刺激下的组织细胞对葡萄糖不敏感或减敏感的状态,导致细胞无法有效地摄取血液中的葡萄糖,从而引起高血糖。腺苷酸激活蛋白激酶(AMPK)是一种能量感应的酶,能够调节多种代谢途径,维持细胞内腺苷三磷酸(ATP)的稳定。近年来中药在T2DM的防治中发挥愈发重要的作用,基于AMPK信号探寻中药干预T2DM进程的研究也逐渐增多。诸多药理研究表明,中药在防治T2DM方面具备安全、高效等优势,AMPK信号通路是中药有效成分、中药提取物发挥改善IR作用的关键通路之一。中药酚类、黄酮类、多糖类、生物碱、皂苷类等有效成分及中药提取物,可以通过激活AMPK信号通路级联反应,从而通过调节糖脂代谢、抑制炎症反应、抗氧化应激和维持线粒体稳态等方式改善IR。基于此,该文章将对近年来中药干预AMPK信号通路改善IR现有的药理和实验研究成果进行综述,以期能为中药干预IR和治疗T2DM的进一步深入研究、开发和应用提供参考。

苓桂术甘汤对心梗后慢性心衰大鼠线粒体分裂-融合及Sirt3/AMPK信号通路的影响

目的:探讨苓桂术甘汤对心肌梗死(MI)后慢性心力衰竭(CHF)大鼠线粒体分裂-融合及沉默信息调节因子3(Sirt3)/单磷酸腺苷依赖的蛋白激酶(AMPK)信号通路的影响。方法:SD大鼠随机分为假手术组(生理盐水,仅穿线不结扎)、模型组(生理盐水,结扎冠状动脉左前降支近心端)、苓桂术甘汤组(4.2 g·kg^(-1))、卡托普利组(0.00257 g·kg^(-1)),每组10只,连续给药28 d。彩色多普勒超声成像仪检测大鼠心功能参数变化;苏木素-伊红(HE)染色观察心脏病理学改变;免疫荧光法检测活性氧(ROS)水平;JC-1法检测线粒体膜电位;比色法检测三磷酸腺苷(ATP)水平、丙二醛(MDA)、超氧化物歧化酶(SOD)、线粒体呼吸链复合物活性(Ⅰ~Ⅳ);原位末端标记法(TUNEL)染色检测心肌组织细胞凋亡率;蛋白免疫印迹法(Western blot)检测Sirt3、磷酸化(p)-AMPK、磷酸化动力相关蛋白1(p-Drp1)、线粒体分裂蛋白1(Fis1)、线粒体分裂因子(MFF)、视神经萎缩蛋白1(OPA1)蛋白表达水平。结果:与假手术组比较,模型组大鼠左室舒张末期内径(LVIDd)、左室收缩末期内径(LVIDs)显著升高(P<0.01),左室短轴缩短率(LVFS)、左室射血分数(LVEF)显著降低(P<0.01);心肌组织出现炎性细胞浸润,病理损伤明显,ROS、MDA水平与心肌细胞凋亡率显著升高(P<0.01),SOD水平、ATP含量、膜电位显著降低(P<0.01);线粒体呼吸链复合物活性(Ⅰ~Ⅳ)显著降低(P<0.01);p-Drp1、Fis1、MFF蛋白水平显著上调(P<0.01),Sirt3、p-AMPK、OPA1蛋白水平显著下调(P<0.01)。与模型组比较,苓桂术甘汤组与卡托普利组LVIDd和LVIDs显著降低(P<0.01),LVEF和LVFS显著升高(P<0.01),心肌组织炎性细胞浸润与病理损伤明显减轻,ROS、MDA水平与心肌细胞凋亡率显著降低(P<0.01),SOD水平、ATP含量、膜电位显著升高(P<0.01);线粒体呼吸链复合物活性(Ⅰ~Ⅳ)显著升高(P<0.01);p-Drp1、Fis1、MFF蛋白表达显著下调(P<0.01),Sirt3、p-AMPK、OPA1蛋白表达显著上调(P<0.01)。结论:苓桂术甘汤可缓解心肌细胞氧化应激与细胞凋亡损伤,改善线粒体功能,其作用可能与线粒体分裂-融合、Sirt3/AMPK信号通路有关。

Panax quinquefolium saponin Optimizes Energy Homeostasis by Modulating AMPK-Activated Metabolic Pathways in Hypoxia-Reperfusion Induced Cardiomyocytes

Objective To investigate the effects and underlying mechanisms of Panax quinquefolium saponin(PQS)on energy deficiency in hypoxia-reperfusion(H/R)induced cardiomyocytes.Methods The H/R injury involved hypoxia for 3 h and then reperfusion for 2 h.Cardiomyocytes recruited from neonatal rat ventricular myocytes(NRVMs)were randomly divided into control,H/R,H/R+compound C(C.C),H/R+PQS,and H/R+C.C+PQS groups.BrdU assay,lactase dehydrogenase(LDH)leakage and early apoptosis rate were evaluated to assess cell damages.Contents of high energy phosphate compounds were conducted to detect the energy production.Protein expression levels of adenosine monophosphate-activated protein kinase a(AMPKα),glucose transporter 4(GLUT4),phosphate fructose kinase 2(PFK2),fatty acid translocase/cluster of differentiation 36(FAT/CD36),and acetyl CoA carboxylase 2(ACC2)in the regulatory pathways were measured by Western blotting.Immunofluorescence staining of GLUT4 and FAT/CD36 was used to observe the mobilization of metabolic transporters.Results PQS(50 mg/L)pretreatment significantly alleviated H/R-induced inhibition of NRVMs viability,up-regulation of LDH leakage,acceleration of early apoptosis,and reduction of energy production(P<0.05).Compared with the H/R group,up-regulated expression of AMPKα,GLUT4,PFK2,FAT/CD36 and ACC2 were observed,and more GLUT4 and FAT/CD36 expressions were detected on the membrane in the H/R+PQS group(P<0.05).These effects of PQS on H/R-induced NRVMs were eliminated in the H/R+C.C+PQS group(P<0.05).Conclusion PQS has prominent advantages in protecting NRVMs from H/R-induced cell damages and energy metabolic disorders,by activation of AMPKα-mediated GLUT4-PFK2 and FAT/CD36-ACC2 pathways.

cPKCγ Deficiency Exacerbates Autophagy Impairment and Hyperphosphorylated Tau Buildup through the AMPK/mTOR Pathway in Mice with Type 1 Diabetes Mellitus

Type 1 diabetes mellitus(T1DM)-induced cognitive dysfunction is common,but its underlying mechanisms are still poorly understood.In this study,we found that knockout of conventional protein kinase C(cPKC)γsignificantly increased the phosphorylation of Tau at Ser214 and neurofibrillary tangles,but did not affect the activities of GSK-3βand PP2A in the hippocampal neurons of T1DM mice.cPKCγdeficiency significantly decreased the level of autophagy in the hippocampal neurons of T1DM mice.Activation of autophagy greatly alleviated the cognitive impairment induced by cPKCγdeficiency in T1DM mice.Moreover,cPKCγdeficiency reduced the AMPK phosphorylation levels and increased the phosphorylation levels of mTOR in vivo and in vitro.The high glucose-induced Tau phosphorylation at Ser214 was further increased by the autophagy inhibitor and was significantly decreased by an mTOR inhibitor.In conclusion,these results indicated that cPKCγpromotes autophagy through the AMPK/mTOR signaling pathway,thus reducing the level of phosphorylated Tau at Ser214 and neurofibrillary tangles.

Novel nervous and multi-system regenerative therapeutic strategies for diabetes mellitus with mTOR

Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin（m TOR） is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1（m TORC1） and m TOR Complex 2（m TORC2） and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase（PI 3-K）,protein kinase B（Akt）,AMP activated protein kinase（AMPK）,silent mating type information regulation 2 homolog 1（Saccharomyces cerevisiae）（SIRT1）,Wnt1 inducible signaling pathway protein 1（WISP1）,and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.

基于AMPK/mTOR信号通路介导自噬探讨中医药治疗心力衰竭的机制研究进展

心力衰竭(HF)是一种由心脏功能障碍引起心室泵血功能受损的一组综合征,严重影响患者的健康和生活质量。HF的发病机制复杂,包括心肌收缩力减退、心肌细胞纤维化和心室重构等多个方面,并与神经内分泌调节、炎症反应及心肌细胞自噬等多种因素有关。自噬是一种细胞通过自我降解的方式,以维持机体稳态的重要调节机制。在HF的进程中,适度的自噬能够清除老化和受损的心肌细胞、维持心肌能量代谢平衡,而异常的自噬则可能会导致心肌细胞的功能减退和病理性改变。腺苷酸活化蛋白激酶(AMPK)/哺乳动物雷帕霉素哺乳靶蛋白(mTOR)则是调控自噬的经典通路之一,可以通过调控AMPK/mTOR信号通路介导心肌细胞自噬过程,起到保护心脏功能,延缓HF进程的作用。中医药在历史长河中不断发展和创新,有着独特的理论体系,并在与现代医学的交汇下表现出卓越的疗效与广泛的应用前景。临床实践中,中医药在治疗心血管疾病方面有着丰富经验,大量国内外研究表明,许多中药有效成分、中药复方及中成药可以通过调节AMPK/mTOR信号通路介导自噬以达到治疗HF的目的。笔者从AMPK/mTOR信号通路介导自噬的作用机制出发,阐释该机制在治疗HF过程中的关键作用,并基于中医相关理论探讨对自噬、AMPK/mTOR信号通路和HF的理解,同时对中医药通过AMPK/mTOR通路调控自噬治疗HF进行了综述,以期深入挖掘中医药在心血管疾病治疗中的潜力,为后续实验研究提供理论支持,并在临床上展现中医优势,实现更加精准化的治疗。

补中益气汤通过Adipor1/AMPK/PGC-1α调节脂代谢治疗运动性疲劳

目的:探讨补中益气汤通过脂联素受体1(Adipor1)/磷酸腺苷活化蛋白激酶(AMPK)/过氧化物酶体增生物激活受体γ共激活因子-1α(PGC-1α)对运动性疲劳(EIF)小鼠骨骼肌中脂代谢的影响。方法:将C57BL/6J小鼠随机分为空白组、模型组、补中益气汤低、中、高剂量组、维生素C组。空白组不施加任何干预,其余组通过力竭游泳建立EIF模型。力竭游泳前1 h,空白组、模型组灌服0.2 mL蒸馏水,补中益气汤低、中、高剂量组分别灌胃4.1、8.2、16.4 g·kg^(-1)的补中益气汤,维生素C组灌胃0.04 g·kg^(-1)剂量维生素C,持续6周。实验6周后,计算小鼠体质量增长率、脏器指数、力竭游泳时间;酶比色法检测小鼠血清中尿素氮(BUN)、肌酸激酶(CK)、乳酸脱氢酶(LDH)、乳酸(LD)的水平;苏木素-伊红(HE)染色观察骨骼肌组织病理变化;透射电镜(TEM)观察骨骼肌组织超微结构;微板法检测血清中游离脂肪酸(NEFA)、甘油三酯(TG)的含量;蛋白免疫印迹法(Western blot)测定骨骼肌中Adipor1、磷酸化(p)-AMPK/AMPK、PGC-1α和己糖激酶2(HK2)蛋白的表达。结果:与空白组比较,模型组小鼠的体质量增长率、胸腺指数降低,血清中BUN、CK、LD、LDH水平升高(P<0.01),NEFA、TG含量下降(P<0.01),骨骼肌组织Adipor1、p-AMPK/AMPK、PGC-1α、HK2蛋白表达下降(P<0.05,P<0.01)。与模型组比较,补中益气汤高剂量组体质量增长率、胸腺指数、力竭游泳时间显著升高(P<0.01),BUN、CK、LD、LDH显著下降(P<0.01),NEFA、TG显著升高(P<0.01),骨骼肌组织Adipor1、p-AMPK/AMPK、PGC-1α、HK2蛋白表达明显升高(P<0.05,P<0.01);维生素C组胸腺指数、力竭游泳时间明显提高,BUN、CK、LD明显下降(P<0.05,P<0.01),NEFA、TG显著升高(P<0.01),骨骼肌组织Adipor1蛋白表达显著升高(P<0.01)。结论:补中益气汤能够延缓EIF的发生,其机制可能与调节Adipor1/AMPK/PGC-1α信号通路,提高骨骼肌对脂肪的利用率有关。

基于AMPK/mTOR自噬通路探讨芍药苷保护溃疡性结肠炎小鼠的作用机制

目的:探讨芍药苷通过腺苷酸活化蛋白激酶(AMPK)/哺乳动物雷帕霉素靶蛋白(mTOR)自噬通路对溃疡性结肠炎(UC)小鼠的保护作用机制研究。方法:自由饮用4%葡聚糖硫酸钠(DSS)建立UC小鼠模型,56只BALB/c雄性小鼠,随机分为模型组、AMPK抑制剂组(20 mg·kg^(-1))、芍药苷(50 mg·kg^(-1))+抑制剂(20 mg·kg^(-1))组、芍药苷高剂量组(50 mg·kg^(-1))、中剂量组(25 mg·kg^(-1))、低剂量组(12.5 mg·kg^(-1))药物干预7 d后,通过比较小鼠体质量、疾病活动指数(DAI)变化和苏木素-伊红(HE)染色结果判断芍药苷对UC的保护作用。酶联免疫吸附测定法(ELISA)检测各组小鼠血清中肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)的水平,免疫荧光检测结肠中微管相关蛋白1轻链3(LC3)的含量,蛋白免疫印迹法(Western blot)检测结肠组织中AMPK、mTOR蛋白及其磷酸化蛋白p-AMPK、p-mTOR,实时荧光定量聚合酶链式反应(Real-time PCR)检测AMPK、mTOR、Beclin1、LC3和p62的mRNA表达水平。结果:与空白组比较,模型组小鼠体质量下降、DAI评分升高、结肠出现严重的病理学损伤,炎症因子TNF-α、IL-6在血清中含量上升(P<0.01),LC3和p-AMPK/AMPK在结肠组织中蛋白水平下调,p-mTOR/mTOR蛋白水平上调(P<0.01);AMPK、LC3的mRNA表达水平下调,mTOR、p62的mRNA表达上调(P<0.01)。与模型组和芍药苷+抑制剂组比较,经芍药苷治疗后小鼠体质量上升、DAI评分降低、结肠组织病理损伤减轻,炎症因子TNF-α、IL-6在血清中含量下降(P<0.05),LC3和p-AMPK/AMPK在结肠组织中蛋白水平上调,p-mTOR/mTOR蛋白水平下调(P<0.01),AMPK、Beclin1、LC3的mRNA表达水平上调,mTOR、p62的mRNA表达下调(P<0.01),抑制剂组小鼠结肠组织病理损伤严重,各项指标趋势与芍药苷高剂量组完全相反。结论:芍药苷可通过激活AMPK/mTOR信号通路,增强自噬,减轻UC小鼠的炎症损伤,从而起到保护作用。

补阳还五汤对舒张性心衰大鼠心肌线粒体能量代谢及AMPK/PPARα信号通路的影响

目的:探讨补阳还五汤基于腺苷酸激活蛋白激酶(AMPK)/过氧化物酶体增殖物激活受体α(PPARα)信号通路对舒张性心衰(DHF)大鼠心肌线粒体能量代谢的影响及其机制研究。方法:将48只SD大鼠随机分为假手术组与模型组,模型组大鼠运用腹主动脉缩窄法建立DHF大鼠模型。将造模成功的大鼠随机分为模型组,补阳还五汤组(12.72 g·kg^(-1)·d^(-1)),酒石酸美托洛尔组(0.004 5 g·kg^(-1)·d^(-1)),灌胃给予相应药物,假手术组、模型组给予等量的去离子水,各组均每日灌胃1次。药物连续干预8周后,采用酶联免疫吸附测定(ELISA)检测大鼠外周血中单磷酸腺苷(AMP),二磷酸腺苷(ADP),三磷酸腺苷(ATP)的含量;采用投射电镜检测心肌线粒体超微结构的变化;采用蛋白免疫印迹法(Western blot)检测大鼠心肌组织中AMPK,PPARα,PPARγ辅助激活因子1α(PGC-1α)的蛋白表达量。结果:与假手术组比较,模型组大鼠AMP,ADP含量显著升高,ATP含量显著下降(P<0.05,P<0.01);与模型组比较,补阳还五汤组、酒石酸美托洛尔组大鼠AMP含量明显降低(P<0.01),ADP含量下降(P<0.05),ATP含量升高。与假手术组比较,模型组大鼠线粒体数量减少,形态异常;与模型组比较,补阳还五汤组、酒石酸美托洛尔组大鼠线粒体数量明显增加,形态明显改善。与假手术组比较,各组大鼠AMPK蛋白表达量无统计学差异;与假手术组比较,模型组PPARα,PGC-1α蛋白表达水平明显降低(P<0.05)。与模型组比较,补阳还五汤组、酒石酸美托洛尔组PPARα,PGC-1α蛋白表达水平明显升高(P<0.05)。结论:补阳还五汤可能是通过改善线粒体结构和功能,激活AMPK并上调AMPK/PPARα信号通路的表达,从而改善衰竭心脏的能量代谢,延缓心衰进展。

基于AMPK/mTOR/ULK1信号通路介导的自噬探讨芪黄益气摄血方治疗免疫性血小板减少症模型小鼠的作用机制

目的:基于腺苷酸活化蛋白激酶/哺乳动物雷帕霉素靶蛋白/Unc-51样激酶1(AMPK/mTOR/ULK1)信号通路介导的自噬探讨芪黄益气摄血方治疗免疫性血小板减少症(ITP)模型小鼠的作用机制。方法:50只BALB/c小鼠随机分为5组,分别为正常组、模型组、芪黄益气摄血方高、低剂量组和强的松组,每组10只。采用豚鼠抗小鼠血小板血清(APS)腹腔注射方法,建立ITP小鼠模型;注射APS后的第8天,各组分别灌胃给药,连续14 d。检测外周血血小板计数(PLT)和血红蛋白(Hb)浓度变化;分离脾脏、胸腺组织,称质量,计算脏器指数;取胸骨做骨髓涂片,显微镜下进行骨髓巨核细胞分类;酶联免疫吸附测定法(ELISA)检测血清血小板生成素(TPO)、白细胞介素-6(IL-6)、白细胞介素-10(IL-10)、肿瘤坏死因子-α(TNF-α)、转化生长因子-β1(TGF-β1)、γ干扰素(IFN-γ)水平;实时荧光定量聚合酶链式反应(Real-time PCR)检测脾脏AMPK、mTOR、ULK1、微管相关蛋白1轻链3(LC3)、自噬关键分子酵母Atg6同系物(Beclin1)、p62 mRNA表达水平;蛋白免疫印迹法(Western blot)检测脾脏AMPK、p-AMPK、p-mTOR、p-ULK1、LC3Ⅱ/LC3Ⅰ、Beclin1、p62蛋白表达水平。结果:与正常组比较,模型组小鼠外周血PLT计数、Hb及TPO水平明显下降(P<0.05,P<0.01),脾脏和胸腺指数显著升高(P<0.01),骨髓产板巨核细胞数显著减少(P<0.01),血清IL-6、TNF-α、IFN-γ水平显著升高(P<0.01),而IL-10、TGF-β1水平显著降低(P<0.01);与模型组比较,芪黄益气摄血方高、低剂量组及强的松组显著增加模型小鼠PLT计数、TPO水平(P<0.01),明显降低脾脏和胸腺指数(P<0.05,P<0.01),明显增加骨髓产板巨核细胞数(P<0.05,P<0.01),明显降低血清IL-6、TNF-α、IFN-γ水平(P<0.05,P<0.01),明显提高IL-10、TGF-β1水平(P<0.05,P<0.01);与芪黄益气摄血方低剂量组比较,芪黄益气摄血方高剂量组和强的松组在改善PLT计数、细胞炎性因子水平方面呈现不同程度的显著性差异(P<0.05,P<0.01)。Real-time PCR和Western blot结果显示,与正常组比较,模型组小鼠脾脏AMPK、LC3、Beclin1 mRNA和p-AMPK/AMPK、LC3Ⅱ/LC3Ⅰ、Beclin1蛋白表达均明显上调(P<0.05,P<0.01),mTOR、ULK1、p62 mRNA和p-mTOR、p-ULK1、p62蛋白表达水平明显下调(P<0.05,P<0.01);与模型组比较,芪黄益气摄血方高、低剂量组及强的松组可明显下调脾脏AMPK、LC3、Beclin1 mRNA和p-AMPK/AMPK、LC3Ⅱ/LC3Ⅰ、Beclin1蛋白表达(P<0.05,P<0.01),同时明显上调mTOR、ULK1、p62 mRNA和p-mTOR、p-ULK1、p62蛋白表达水平(P<0.05,P<0.01)。结论:芪黄益气摄血方可能通过调控AMPK/mTOR/ULK1信号通路抑制自噬的过度发生,从而调节免疫失耐受,发挥治疗ITP作用。

益肾通络方对膜性肾病大鼠的肾保护作用及对AMPK/mTOR/ULK1信号通路的影响

目的:通过观察益肾通络方对膜性肾病大鼠自噬相关蛋白的影响,探讨其对膜性肾病大鼠肾脏保护作用的可能分子机制。方法:80只SD大鼠随机抽取20只设为正常组,其余大鼠均采用预免疫和尾静脉注射阳离子化牛血清白蛋白(C-BSA)的方法制作膜性肾病大鼠模型。将模型复制成功的SD大鼠随机分为模型组,盐酸贝那普利组(10 mg·kg-1)及益肾通络方低、中、高剂量组(6.61,13.22,26.44 g·kg-1),给予相应剂量的药物灌胃,每天1次,连续灌胃4周。灌胃结束后,检测大鼠血浆白蛋白(ALB),甘油三酯(TG),胆固醇(TC),血肌酐(SCr),尿素氮(BUN),24 h尿蛋白(UTP)定量指标的变化;苏木素-伊红(HE)染色、马松(Masson)染色、碘酸六胺银(PASM)染色及透射电镜下观测肾脏病理形态改变;免疫荧光法检测肾小球中免疫球蛋白(Ig)G和补体C3的沉积;免疫组化(IHC)法观察自噬标志蛋白Beclin-1,微管相关蛋白轻链3Ⅱ(LC3Ⅱ),p62蛋白的表达情况;蛋白免疫印迹法(Western blot)检测腺苷酸活化蛋白激酶/雷帕霉素靶蛋白/Unc-51样激酶1(AMPK/mTOR/ULK1)信号通路相关蛋白的表达情况。结果:与正常组比较,模型组大鼠UTP水平显著升高(P<0.01),血清中TG,TC水平显著升高(P<0.01),ALB水平显著下降(P<0.01);肾小球结构紊乱,体积增大,基底膜可见不同程度增厚和部分肾小管空泡样变性,大量胶原纤维和嗜复红蛋白沉积,足细胞足突广泛融合,肾小球毛细血管襻IgG和补体C3弥漫性沉积;自噬标志蛋白Beclin-1,LC3Ⅱ表达显著降低(P<0.01),p62蛋白表达显著升高(P<0.01);磷酸化-腺苷酸活化蛋白激酶(p-AMPK)蛋白表达显著降低(P<0.01),磷酸化-雷帕霉素靶蛋白(p-mTOR),磷酸化-Unc-51样激酶1(p-ULK1)蛋白表达显著升高(P<0.01);与模型组比较,益肾通络方各剂量组、盐酸贝那普利组大鼠TG,TC,UTP水平均有不同程度降低(P<0.05,P<0.01),ALB水平显著升高(P<0.01),血清SCr,BUN水平均差异无统计学意义;肾脏病理损害不同程度减轻;自噬标志蛋白Beclin-1,LC3Ⅱ表达水平不同程度升高(P<0.05,P<0.01),p62蛋白表达不同程度降低(P<0.05,P<0.01);p-AMPK蛋白表达水平不同程度升高(P<0.05,P<0.01),p-mTOR,p-ULK1蛋白表达水平不同程度降低(P<0.05,P<0.01)。结论:益肾通络方对膜性肾病大鼠具有肾脏保护作用,其机制可能与调控AMPK/mTOR/ULK1信号通路相关蛋白的表达,激活自噬有关。