Netrin-1 signaling pathway mechanisms in neurodegenerative diseases

Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic function.Increasing amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of cancers.These findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative diseases.Through a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.

Argatroban promotes recovery of spinal cord injury by inhibiting the PAR1/JAK2/STAT3 signaling pathway

Argatroban is a synthetic thrombin inhibitor approved by U.S.Food and Drug Administration for the treatment of thrombosis.However,whether it plays a role in the repair of spinal cord injury is unknown.In this study,we established a rat model of T10 moderate spinal cord injury using an NYU Impactor ModerⅢand performed intraperitoneal injection of argatroban for 3 consecutive days.Our results showed that argatroban effectively promoted neurological function recovery after spinal cord injury and decreased thrombin expression and activity in the local injured spinal cord.RNA sequencing transcriptomic analysis revealed that the differentially expressed genes in the argatroban-treated group were enriched in the JAK2/STAT3 pathway,which is involved in astrogliosis and glial scar formation.Western blotting and immunofluorescence results showed that argatroban downregulated the expression of the thrombin receptor PAR1 in the injured spinal cord and the JAK2/STAT3 signal pathway.Argatroban also inhibited the activation and proliferation of astrocytes and reduced glial scar formation in the spinal cord.Taken together,these findings suggest that argatroban may inhibit astrogliosis by inhibiting the thrombin-mediated PAR1/JAK2/STAT3 signal pathway,thereby promoting the recovery of neurological function after spinal cord injury.

Spi1 regulates the microglial/macrophage inflammatory response via the PI3K/AKT/mTOR signaling pathway after intracerebral hemorrhage

Preclinical and clinical studies have shown that microglia and macrophages participate in a multiphasic brain damage repair process following intracerebral hemorrhage.The E26 transformation-specific sequence-related transcription factor Spi1 regulates microglial/macrophage commitment and maturation.However,the effect of Spi1 on intracerebral hemorrhage remains unclear.In this study,we found that Spi1 may regulate recovery from the neuroinflammation and neurofunctional damage caused by intracerebral hemorrhage by modulating the microglial/macrophage transcriptome.We showed that high Spi1expression in microglia/macrophages after intracerebral hemorrhage is associated with the activation of many pathways that promote phagocytosis,glycolysis,and autophagy,as well as debris clearance and sustained remyelination.Notably,microglia with higher levels of Soil expression were chara cterized by activation of pathways associated with a variety of hemorrhage-related cellular processes,such as complement activation,angiogenesis,and coagulation.In conclusion,our results suggest that Spi1 plays a vital role in the microglial/macrophage inflammatory response following intracerebral hemorrhage.This new insight into the regulation of Spi1 and its target genes may advance our understanding of neuroinflammation in intracerebral hemorrhage and provide therapeutic targets for patients with intracerebral hemorrhage.

Downregulation of MUC1 Inhibits Proliferation and Promotes Apoptosis by Inactivating NF-κB Signaling Pathway in Human Nasopharyngeal Carcinoma

Objective To investigate the effect of mucin 1(MUC1)on the proliferation and apoptosis of nasopharyngeal carcinoma(NPC)and its regulatory mechanism.Methods The 60 NPC and paired para-cancer normal tissues were collected from October 2020 to July 2021 in Quanzhou First Hospital.The expression of MUC1 was measured by real-time quantitative PCR(qPCR)in the patients with PNC.The 5-8F and HNE1 cells were transfected with siRNA control(si-control)or siRNA targeting MUC1(si-MUC1).Cell proliferation was analyzed by cell counting kit-8 and colony formation assay,and apoptosis was analyzed by flow cytometry analysis in the 5-8F and HNE1 cells.The qPCR and ELISA were executed to analyze the levels of TNF-αand IL-6.Western blot was performed to measure the expression of MUC1,NFкB and apoptosis-related proteins(Bax and Bcl-2).Results The expression of MUC1 was up-regulated in the NPC tissues,and NPC patients with the high MUC1 expression were inclined to EBV infection,growth and metastasis of NPC.Loss of MUC1 restrained malignant features,including the proliferation and apoptosis,downregulated the expression of p-IкB、p-P65 and Bcl-2 and upregulated the expression of Bax in the NPC cells.Conclusion Downregulation of MUC1 restrained biological characteristics of malignancy,including cell proliferation and apoptosis,by inactivating NF-κB signaling pathway in NPC.

LRP1 facilitates hepatic glycogenesis by improving the insulin signaling pathway in HFD-fed mice

Background: LDL receptor-related protein-1(LRP1) is a cell-surface receptor that functions in diverse physiological pathways. We previously demonstrated that hepatocyte-specific LRP1 deficiency(hLRP1KO) promotes diet-induced insulin resistance and increases hepatic gluconeogenesis in mice. However, it remains unclear whether LRP1 regulates hepatic glycogenesis.Methods: Insulin signaling, glycogenic gene expression, and glycogen content were assessed in mice and HepG2 cells. The pcDNA 3.1 plasmid and adeno-associated virus serotype 8 vector(AAV8) were used to overexpress the truncated β-chain(βΔ) of LRP1 both in vitro and in vivo.Results: On a normal chow diet, hLRP1KO mice exhibited impaired insulin signaling and decreased glycogen content. Moreover, LRP1 expression in HepG2 cells was significantly repressed by palmitate in a dose-and time-dependent manner. Both LRP1 knockdown and palmitate treatment led to reduced phosphorylation of Akt and GSK3β, increased levels of phosphorylated glycogen synthase(GYS), and diminished glycogen synthesis in insulin-stimulated HepG2 cells, which was restored by exogenous expression of the βΔ-chain. By contrast, AAV8-mediated hepatic βΔ-chain overexpression significantly improved the insulin signaling pathway, thus activating glycogenesis and enhancing glycogen storage in the livers of high-fat diet(HFD)-fed mice.Conclusion: Our data revealed that LRP1, especially its β-chain, facilitates hepatic glycogenesis by improving the insulin signaling pathway, suggesting a new therapeutic strategy for hepatic insulin resistance-related diseases.

Enhancement of porcine in vitro embryonic development through luteolin‑mediated activation of the Nrf2/Keap1 signaling pathway

Background Oxidative stress,caused by an imbalance in the production and elimination of intracellular reactive oxygen species(ROS),has been recognized for its detrimental effects on mammalian embryonic development.Luteolin(Lut)has been documented for its protective effects against oxidative stress in various studies.However,its specific role in embryonic development remains unexplored.This study aims to investigate the influence of Lut on porcine embryonic development and to elucidate the underlying mechanism.Results After undergoing parthenogenetic activation(PA)or in vitro fertilization,embryos supplemented with 0.5μmol/L Lut displayed a significant enhancement in cleavage and blastocyst formation rates,with an increase in total cell numbers and a decrease in the apoptosis rate compared to the control.Measurements on D2 and D6 revealed that embryos with Lut supplementation had lower ROS levels and higher glutathione levels compared to the control.Moreover,Lut supplementation significantly augmented mitochondrial content and membrane potential.Intriguingly,activation of the Nrf2/Keap1 signaling pathway was observed in embryos supplemented with Lut,leading to the upregulation of antioxidant-related gene transcription levels.To further validate the relationship between the Nrf2/Keap1 signaling pathway and effects of Lut in porcine embryonic development,we cultured PA embryos in a medium supplemented with brusatol,with or without the inclusion of Lut.The positive effects of Lut on developmental competence were negated by brusatol treatment.Conclusions Our findings indicate that Lut-mediated activation of the Nrf2/Keap1 signaling pathway contributes to the enhanced production of porcine embryos with high developmental competence,and offers insight into the mechanisms regulating early embryonic development.

Pachymic acid exerts antitumor activities by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B

Objective:To determine the inhibitory effects of pachymic acid on lung adenocarcinoma(LUAD)cells and elucidate its underlying mechanism.Methods:CCK-8,wound healing,Transwell,Western blot,tube formation,and immunofluorescence assays were carried out to measure the effects of various concentrations of pachymic acid on LUAD cell proliferation,metastasis,angiogenesis as well as autophagy.Subsequently,molecular docking technology was used to detect the potential targeted binding association between pachymic acid and protein tyrosine phosphatase 1B(PTP1B).Moreover,PTP1B was overexpressed in A549 cells to detect the specific mechanisms of pachymic acid.Results:Pachymic acid suppressed LUAD cell viability,metastasis as well as angiogenesis while inducing cell autophagy.It also targeted PTP1B and lowered PTP1B expression.However,PTP1B overexpression reversed the effects of pachymic acid on metastasis,angiogenesis,and autophagy as well as the expression of Wnt3a andβ-catenin in LUAD cells.Conclusions:Pachymic acid inhibits metastasis and angiogenesis,and promotes autophagy in LUAD cells by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B.

Exploring the effect of Bushen Bitong recipe-containing serum on IL-1β-induced chondrocyte apoptosis based on SOX9/NF-κB/MMP-13 signaling pathway

Objective:To observe the effect and possible mechanism of action of Bushen Bitong recipe(BSBT)containing serum on IL-1β-induced chondrocyte apoptosis.Methods:Generation 3 rat chondrocytes were randomized into Control,IL-1β,IL-1β+BSBT(L),IL-1β+BSBT(M),and IL-1β+BSBT(H)groups(5%,10%and 15%BSBT-containing serum),and then 24h after intervention respectively,the cell proliferation and Apoptosis rate;Western blot detected the expression levels of Bcl-2,BAX,Caspase-3,SOX9,NF-κB p65,MMP-13 proteins in chondrocytes.ELISA detected the levels of TNF-α,IL-6,and bFGF in the supernatants of chondrocyte culture.Results:Compared with Control group,cell proliferation activity decreased,apoptosis rate increased,NF-κB p65,MMP-13 protein level and TNF-α,IL-6 level increased,and SOX9 protein level and bFGF level decreased in IL-1βgroup;compared with IL-1βgroup,different concentrations of BSBT-containing serum group,cell proliferation activity increased,and apoptosis rate decreased.NF-κB p65,MMP-13 protein level and TNF-α,IL-6 level decreased,SOX9 protein level and bFGF level increased;compared with IL-1β+BSBT(L)group,cell proliferation activity increased,apoptosis rate decreased in IL-1β+BSBT(M)and IL-1β+BSBT(H)groups,and NF-κB p65,MMP-13 protein level and TNF-αlevel decreased.13 protein levels and TNF-αand IL-6 levels decreased,and SOX9 protein levels and bFGF levels increased.Conclusion:BSBT-containing serum may promote IL-1β-induced proliferation of chondrocytes,reduce apoptosis,improve the microenvironment of chondrocytes,and promote cartilage repair through the SOX9/NF-κB/MMP-13 signaling pathway.

Electroacupuncture improves myocardial fibrosis in heart failure rats by attenuating ECM collagen deposition through modulation of TGF-β1/Smads signaling pathway

Background: To explore the effects of electroacupuncture on cardiac function and myocardial fibrosis in rat models of heart failure, and to elucidate the underlying mechanism of electroacupuncture in heart failure treatment. Methods: Healthy male Sprague-Dawley rats were allocated into three groups: Sham group, Model group, and electroacupuncture (Model + EA) group, with each group comprising 8 rats. The model underwent a procedure involving the ligation of the left anterior descending coronary artery to induce a model of heart failure. The Model + EA group was used for 7 consecutive days for electroacupuncture of bilateral Shenmen (HT7) and Tongli (HT5), once a day for 30 min each time. Left ventricular parameters in rats were assessed using a small-animal ultrasound machine to analyze changes in left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular ejection fraction, and left ventricular fractional shortening. Serum interleukin-1β (IL-1β), cardiac troponin (cTn), and N-terminal brain natriuretic peptide precursor levels were measured using ELISA. Histopathological changes in rat myocardium were observed through HE staining, while collagen deposition in rat myocardial tissue was assessed using the Masson staining method. Picro sirius red staining, immunohistochemical staining, and RT-qPCR were utilized to distinguish between the various types of collagen deposition. The expression level of TGF-β1 and SMAD2/3/4/7 mRNA in rat myocardial tissues was determined using RT-qPCR. Additionally, western blot analysis was conducted to assess the protein expression levels of TGF-β1, SMAD3/7, and p-SMAD3 in rat myocardial tissues. Results: Compared with the Sham group, the left ventricular ejection fraction and left ventricular fractional shortening values of the Model group were significantly decreased (P < 0.01);the left ventricular end-diastolic volume and left ventricular end-systolic volume values were remarkably increased (P < 0.01);serum N-terminal brain natriuretic peptide precursor content was increased (P < 0.01);serum IL-1β and cTn levels were increased (P < 0.01);myocardial collagen volume fraction were increased (P < 0.01);and those of the expression of TGF-β1 and SMAD2/3/4 mRNA was increased (P < 0.01);the expression of SMAD7 mRNA was decreased (P < 0.01);the protein expression levels of TGF-β1, SMAD3, and p-Smad3 were increased (P < 0.01);the protein expression level of SMAD7 was decreased (P < 0.01) in the Model group. Compared to the Model group, the expression levels of the proteins TGF-β1, SMAD3, and p-Smad3 in myocardial tissue were found to be decreased (P < 0.01), and the expression level of the protein SMAD7 was found to be increased (P < 0.01) in the Model + EA group;the collagen volume fraction and deposition of type Ⅰ /Ⅲ collagen were decreased (P < 0.01) in the Model + EA group. Conclusion: Electroacupuncture alleviates myocardial fibrosis in rats with heart failure, and this effect is likely due to attributed to the modulation of the TGF-β1/Smads signaling pathway, which helps reduce collagen deposition in the extracellular matrix.

Exploring the mechanism of electroacupuncture at different acupoints on acute colitis rats based on JAK2/STAT3/SOCS1 signaling pathway

Objective:To investigate the mechanism of JAK2/STAT3/SOCS1 signaling pathway in electroacupuncture of different acupoints on acute colitis rats.Methods:36 SPF SD rats were randomly divided into 6 groups,with 6 rats in each group.The rat model of acute colitis was prepared by enema with glacial acetic acid solution.After the model was established,electroacupuncture was given to each acupoint group,with density wave,frequency 2Hz-50 Hz,intensity 2 mA,muscle tremor as the degree 20 min/time,1 time/day,for 3 consecutive days.Observe the general condition of rats;the pathological changes of colonic mucosa in rats were observed by HE method.The contents of serum interleukin-4(IL-4)and interleukin-8(IL-8)were detected by ELISA.Western blot and RT-PCR were used to detect the expression of JAK2,STAT3,SOCS1 protein and mRNA in rat colon tissue.Results:In contrast to the normal group,the overall condition of the model group was worse,the colonic mucosa was severely damaged,even necrotic,and the ulcer surface was obvious.The content of IL-4 in serum was obviously reduced,and the content of IL-8 was obviously go up(P<0.01).The protein content of JAK2,STAT3 and the expression of JAK2,STAT3 mRNA in colon tissue of rats were obviously go up,while the protein content of SOCS1 and the expression of SOCS1 mRNA were obviously reduced(P<0.01).In contrast to the model group,the general condition of rats in each acupoint group was significantly improved,the damage and necrosis of colonic mucosa and ulcer surface were obviously alleviated,the content of IL-4 in serum was obviously go up,and the content of IL-8 was significantly decreased(P<0.01).The protein content of JAK2,STAT3 and the expression of JAK2,STAT3 mRNA in colon tissue of rats were obviously reduced,while the protein content of SOCS1 and the expression of SOCS1 mRNA were obviously go up(P<0.05,P<0.01).Comparison of different acupoint groups,the colonic mucosal injury in the Zusanli group was significantly reduced,the content of serum IL-4 was significantly increased,and the content of IL-8 was significantly decreased(P<0.05,P<0.01).The protein content and mRNA expression of JAK2 and STAT3 in colon tissue were significantly down-regulated,while the protein content and mRNA expression of SOCS1 were significantly go up(P<0.05,P<0.01).Conclusion:Electroacupuncture at each acupoint can improve the damage of colonic mucosa and reduce the inflammatory response.The therapeutic effect of Zusanli(ST36)is better than that of Tianshu(ST25),Dachangshu(BL25)and Shangjuxu(ST37).The mechanism may be related to the regulation of JAK2/STAT3/SOCS1 signaling pathway related proteins and inflammatory cytokines IL-4 and IL-8.

X-Paste improves wound healing in diabetes via NF-E2-related factor/HO-1 signaling pathway

BACKGROUND Diabetic foot ulcers(DFU),as severe complications of diabetes mellitus(DM),significantly compromise patient health and carry risks of amputation and mortality.AIM To offer new insights into the occurrence and development of DFU,focusing on the therapeutic mechanisms of X-Paste(XP)of wound healing in diabetic mice.METHODS Employing traditional Chinese medicine ointment preparation methods,XP combines various medicinal ingredients.High-performance liquid chromatography(HPLC)identified XP’s main components.Using streptozotocin(STZ)-induced diabetic,we aimed to investigate whether XP participated in the process of diabetic wound healing.RNA-sequencing analyzed gene expression differences between XP-treated and control groups.Molecular docking clarified XP’s treatment mechanisms for diabetic wound healing.Human umbilical vein endothelial cells(HUVECs)were used to investigate the effects of Andrographolide(Andro)on cell viability,reactive oxygen species generation,apoptosis,proliferation,and metastasis in vitro following exposure to high glucose(HG),while NF-E2-related factor-2(Nrf2)knockdown elucidated Andro’s molecular mechanisms.RESULTS XP notably enhanced wound healing in mice,expediting the healing process.RNA-sequencing revealed Nrf2 upregulation in DM tissues following XP treatment.HPLC identified 21 primary XP components,with Andro exhibiting strong Nrf2 binding.Andro mitigated HG-induced HUVECs proliferation,metastasis,angiogenic injury,and inflammation inhibition.Andro alleviates HG-induced HUVECs damage through Nrf2/HO-1 pathway activation,with Nrf2 knockdown reducing Andro’s proliferative and endothelial protective effects.CONCLUSION XP significantly promotes wound healing in STZ-induced diabetic models.As XP’s key component,Andro activates the Nrf2/HO-1 signaling pathway,enhancing cell proliferation,tubule formation,and inflammation reduction.

扶正解毒方对病毒性心肌炎大鼠氧化应激及Sirt1/FoxO3a通路的影响

目的 基于沉默信息调节因子2相关酶1(Sirt1)/叉头蛋白O3a(FoxO3a)通路探究扶正解毒方对病毒性心肌炎(VMC)大鼠的影响。方法 大鼠腹腔注射柯萨奇B3病毒(CVB3)法建立VMC模型,随机分为模型组、扶正解毒方低剂量组(28 g/kg)、扶正解毒方高剂量组(112 g/kg)、EX527组(Sirt1抑制剂,1μg/kg)、扶正解毒方(28 g/kg)+EX527(1μg/kg)组,每组15只,另取未造模的正常大鼠15只为正常组,连续给药10 d。检测大鼠超声心动图Tie指数,HE染色观察心肌组织病理损伤情况,ELISA法检测血清心肌损伤标志物、氧化应激水平,TUNEL法检测心肌组织细胞凋亡率,免疫组化法检测心肌组织Sirt1表达,Western blot法检测心肌组织FoxO3a、磷酸化FoxO3a(p-FoxO3a)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GPx)、过氧化氢酶(CAT)、细胞周期抑制蛋白p27、半胱氨酸天冬氨酸蛋白水解酶3(caspase3)表达。结果 与正常组比较,模型组大鼠心肌细胞坏死加重,大鼠出现死亡,Tie指数、血清心肌损伤标志物、氧化应激指标水平均升高(P<0.05),Sirt1/FoxO3通路蛋白及其介导的抗氧化应激、抗凋亡相关蛋白表达降低(P<0.05);与模型组比较,扶正解毒方各剂量组大鼠无死亡,心肌组织损伤得以缓解,Tie指数、血清心肌损伤标志物、氧化应激指标水平均降低(P<0.05),Sirt1/FoxO3通路蛋白及其介导的抗氧化应激、抗凋亡相关蛋白表达升高(P<0.05);EX527可加重VMC大鼠的死亡及心肌细胞氧化损伤等症状,并逆转扶正解毒方对抗病毒性心肌炎的作用(P<0.05)。结论 扶正解毒方可通过激活Sirt1/FoxO3a通路缓解VMC大鼠心肌氧化应激损伤。

川陈皮素通过FOXO3a/SIRT1通路减轻脂多糖诱导的肺损伤

目的 观察川陈皮素在脓毒症肺损伤中的作用,并探究其潜在机制。方法 采用随机数字表法将48只8~10周的雄性C57 BL/6小鼠分为4组,即对照组、肺损伤组、治疗组(5mg/kg)和治疗组(10mg/kg),每组各12只。对照组不做任何处理;肺损伤组小鼠腹腔注射脂多糖(10mg/kg);治疗组(5mg/kg)小鼠接受腹腔注射脂多糖(10mg/kg)的同时予以川陈皮素(5mg/kg)灌胃;治疗组(10mg/kg)小鼠接受腹腔注射脂多糖(10mg/kg),同时予以川陈皮素(10mg/kg)灌胃。脂多糖腹腔注射12h后,检测各组小鼠肺功能及动脉血气,同时留取肺组织,分别从病理学和分子生物学层面评估小鼠肺损伤状况及可能靶点。结果 与对照组比较,肺损伤组小鼠气道压力、PaCO_(2)、肺损伤评分明显增高,PaO_(2)明显降低(P<0.05);与肺损伤组比较,治疗组(5mg/kg)和治疗组(10mg/kg)小鼠气道压力、PaCO_(2)、肺损伤评分明显降低,PaO_(2)明显升高(P<0.05)。Western blot法检测结果显示,与对照组比较,肺损伤组小鼠肺组织中IL-1β、TNF-α、TXNIP和4-HNE的蛋白表达水平明显升高(P<0.05);与肺损伤组比较,治疗组(5mg/kg)和治疗组(10mg/kg)小鼠肺组织上述蛋白表达水平明显降低(P<0.05)。此外,肺损伤组小鼠肺组织中FOXO3a和SIRT1的蛋白表达水平较对照组明显降低(P<0.05);与肺损伤组比较,治疗组(5mg/kg)和治疗组(10mg/kg)小鼠肺组织中FOXO3a和SIRT1蛋白表达水平明显上调(P<0.05)。结论 川陈皮素可抑制小鼠脓毒症肺损伤并减轻氧化应激和炎性反应,其机制可能与川陈皮素对FOXO3a/SIRT1通路激活有关。

CHANGES IN NEUROPEPTIDES AFTER MUSIC EXPOSURE 429Cardioprotective effect of ivabradine via the AMPK/SIRT1/PGC-1αsignaling pathway in myocardial ischemia/reperfusion injuryinduced in H9c2 cell

Post-resuscitation myocardial dysfunction(PRMD)is the most severe myocardial ischemia-reperfusion injury(MIRI)and is characterized by difficult treatment and poor prognosis.Research has shown the protective effects of the rational use of ivabradine(IVA)against PRMD,however,the molecular mechanisms of IVA remain unknown.In this study,an ischemia-reperfusion injury(IRI)model was established using hypoxic chambers.The results demonstrated that pretreatment with IVA reduced IRI-induced cytotoxicity and apoptosis.IVA attenuated mitochondrial damage,eliminated excess reactive oxygen species(ROS),suppressed IRI-induced ATP and NAD+,and increased the AMP/ATP ratio.We further found that IVA increased the mRNA levels of sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α)and upregulated the expression levels of phosphorylated AMP-activated protein kinase(p-AMPK)/AMPK,SIRT1,and PGC-1αproteins.Interestingly,no change in AMPK mRNA levels was observed.Cardiomyocyte energy metabolism significantly changed after IRI.The aim of this study was to demonstrate the cardioprotective effect of Ivabradine via the AMPK/SIRT1/PGC-1αsignaling pathway in myocardial ischemia/reperfusion injury-induced in H9c2 cell.

Mechanism of Resveratrol on autophagy mediated by Mst1/Sirt3 signaling pathway in diabetic cardiomyopathy

Objective:To observe the effects of resveratrol on myocardial cell injury and Mst1/Sirt3 signaling pathway mediated autophagy in type 2 diabetic mice. Methods:C57 BL/KSJ db/db mice were allocated to the normal control group,the model group,and the resveratrol group;C57 BL/KSJ db/m mice served as the melbine group,with 10 mice each. The resveratrol group and the melbine group were treated with resveratrol and metformin by gavage,respectively. The normal control group and the model group were treated with equal volume of normal saline by gavage,for 8 consecutive weeks. H & E staining,transmission electron microscopy and immunofluorescence were used to observe the pathological morphology,ultrastructure and apoptosis levels of myocardial tissues,respectively. RT-qPCR method was used to detect the expression levels of apoptosis genes Bax and Bcl-2 in myocardial tissues,and Western-blot method was used to detect the expression levels of autophagy proteins(LC3 and p62),Mst1 and Sirt3 proteins in myocardial tissue. Results:Compared with the model group,resveratrol can significantly reduce the body weight,blood glucose level and serum CK and LDH levels of db/db mice,and the differences were statistically significant(P<0.05;P<0.01). Meanwhile,after resveratrol treatment,myocardial inflammation score,apoptosis rate,Bax mRNA expression level and Bax/Bcl-2 ratio in myocardial tissue were significantly reduced,and Bcl-2 mRNA expression level was significantly increased,and the differences were statistically significant(P<0.01). In addition,compared with the model group,the expression level of p62 and p-Mst1 protein in the myocardial tissue of the resveratrol group was significantly reduced,and the expression level of Sirt3 protein and the ratio of LC3Ⅱ/LC3Ⅰ were significantly increased,and the differences were statistically significant(P<0.01). Conclusion:Resveratrol promotes the autophagy level of cardiomyocytes by activating the Mst1/Sirt3 signaling pathway and inhibits cardiomyocyte apoptosis to play a protective role in diabetic cardiomyopathy.

Mechanism of hesperidin improving myocardial ischemia/reperfusion injury in type 2 diabetic rats through SIRT1/Nrf2/HO-1 signaling pathway

Objective:To observe the protective effect of hesperidin on myocardial ischemia/reperfusion injury in type 2 diabetes mellitus and its effect on SIRT1/Nrf2/HO-1 signaling pathway.Methods:50 Sprague-Dawley(SD)rats were randomly assigned to the normal control group(NC),model group,ischemia-reperfusion group(IR),hesperidin group,SIRT1 inhibitor group and hesperidin plus SIRT1 inhibitor group.In addition to NC,the rats in the remaining groups were replicated by intraperitoneal of high-fat diet combined with injection of streptozotocin for type 2 diabetic rats.After then,the myocardial ischemia/reperfusion injury(MIRI)rat model was established by LAd for 30 minutes with 2 hours reperfusion.He staining was used to observe the pathological changes of myocardial tissue,and the levels of serum LDH,CK-MB and SOD,GSH and MDA in myocardial tissue were detected by kit methods,and the expression abundance of related proteins in 4-HNE and SIRT1/Nrf2/HO-1 signal pathway were detected by immunohistochemistry and Western blot;Results:Hesperidin could significantly inhibit cardiomyocyte necrosis and inflammatory cell infiltration,reduce LDH activity,CK-MB and MDA level,and increase SOD activity,GSH and 4-HNE level,the differences were statistically significant when compared with IR group(P<0.01).In addition,compared with the ischemia-reperfusion group,the expressions of SIRT1,Nrf2 and HO-1 proteins in hesperidin group were significantly up-regulated,the differences were statistically significant(P<0.01);Conclusion:Hesperidin inhibits oxidative stress by activating SIRT1/Nrf2/HO-1 signaling pathway,and play a protective effect of myocardial ischemia reperfusion injury in diabetic rats.

Effect and Mechanism of Dicliptera chinensis Polysaccharide on miR-141/AMPK/SIRT1 Signaling Pathway in Rats with NAFLD

[Objectives]Non-alcoholic fatty liver disease(NAFLD)rat model was established by feeding high-fat and high-sugar fodder to rats,and the protective effect of Dicliptera chinensis polysaccharide(DCP)on NAFLD rats was studied to explore its potential mechanism.[Methods]45 SD rats were randomly divided into 4 groups:normal control group,model control group and DCP treatment groups(100 and 300 mg/kg).The rats in the normal control group were fed with ordinary fodder,and the rats in other groups were fed with high-fat and high-sugar diet for 14 weeks to establish NAFLD model.From the 9^(th)week,the rats in the DCP treatment groups were given different doses of DCP by intragastric administration(5 mL/kg)for 6 weeks.After the last intragastric administration,the rats fasted for 16 h,and the serum and liver of rats were collected for detection.Hematoxylin-eosin(HE)staining was conducted to observe the histopathological changes of rat liver,and alanine aminotransferase(ALT),aspartate aminotransferase(AST),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA),triglyceride(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),and high density lipoprotein cholesterol(HDL-C)were detected by biochemical method.Interleukin-6(IL-6),interleukin-1β(IL-1β),tumor necrosis factor(TNF-α)and micrornA-141(micro RNA-141)were detected by reverse transcription-polymerase chain reaction(RT-PCR).The expression of SIRT1 and adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)in rat liver was detected by western blot.[Results]Compared with the model control group,the inflammatory damage and steatodegeneration of rats in the DCP groups were relieved to varying degrees,and the number of lipid vacuoles significantly reduced.The ALT,AST,TC,TG and LDL-C content in the serum and MDA content in the liver tissue decreased to varying degrees,while the HDL-C,SOD and GSH-Px content increased.The expression of SIRT1 and AMPK increased,while the expression of miR-141,TNF-α,IL-6 and IL-1βdeclined,and the DCP 300 mg/kg treatment group had better improvement effect.[Conclusions]DCP had a certain protective effect on NAFLD rats,which may be related to the regulation of miR-141/AMPK/SIRT1 signaling pathway.

Corilagin alleviates podocyte injury in diabetic nephropathy by regulating autophagy via the SIRT1-AMPK pathway

BACKGROUND Diabetic nephropathy(DN)is the most frequent chronic microvascular consequence of diabetes,and podocyte injury and malfunction are closely related to the development of DN.Studies have shown that corilagin(Cor)has hepatoprotective,anti-inflammatory,antibacterial,antioxidant,anti-hypertensive,antidiabetic,and anti-tumor activities.AIM To explore the protective effect of Cor against podocyte injury in DN mice and the underlying mechanisms.METHODS Streptozotocin and a high-fat diet were combined to generate DN mice models,which were then divided into either a Cor group or a DN group(n=8 in each group).Mice in the Cor group were intraperitoneally injected with Cor(30 mg/kg/d)for 12 wk,and mice in the DN group were treated with saline.Biochemical analysis was used to measure the blood lipid profiles.Hematoxylin and eosin staining was used to detect pathological changes in kidney tissue.Immunohistochemistry and Western blotting were used to assess the protein expression of nephrin and podocin.Mouse podocyte cells(MPC5)were cultured and treated with glucose(5 mmol/L),Cor(50μM),high glucose(HG)(30 mmol/L),and HG(30 mmol/L)plus Cor(50μM).Real-time quantitative PCR and Western blotting RESULTS Compared with the control group,the DN mice models had increased fasting blood glucose,glycosylated hemoglobin,triglycerides,and total cholesterol,decreased nephrin and podocin expression,increased apoptosis rate,elevated inflammatory cytokines,and enhanced oxidative stress.All of the conditions mentioned above were alleviated after intervention with Cor.In addition,Cor therapy improved SIRT1 and AMPK expression(P<0.001),inhibited reactive oxygen species and oxidative stress,and elevated autophagy in HG-induced podocytes(P<0.01).CONCLUSION Cor alleviates podocyte injury by regulating autophagy via the SIRT1-AMPK pathway,thereby exerting its protective impact on renal function in DN mice.

基于SIRT1/FOXO3a信号通路探讨“温阳通脉”灸法对ApoE^(-/-)动脉粥样硬化小鼠炎症反应的影响

【目的】探讨“温阳通脉”灸法防治动脉粥样硬化(AS)的作用机制。【方法】将10只饲喂普通饲料的C57BL/6J小鼠设为空白组;将30只ApoE^(-/-)小鼠给予高脂饲料喂养建立动脉粥样硬化模型,随机分为模型组、辛伐他汀组和艾灸组,每组10只。于造模第1天开始干预,艾灸组小鼠给予膻中、神阙、内关、血海穴艾灸,辛伐他汀组给予辛伐他汀蒸馏水混悬液灌胃,共干预12周。给药结束后,采用苏木素-伊红(HE)染色法观察小鼠胸主动脉病理形态结构,透射电镜观察小鼠胸主动脉内皮细胞超微结构,酶联免疫吸附法(ELISA)检测小鼠血清肿瘤坏死因子α(TNF-α)、细胞间黏附分子1(ICAM-1)、血管细胞黏附分子1(VCAM-1)水平,实时定量聚合酶链反应(qRT-PCR)法检测胸主动脉沉默信息调节因子1(SIRT1)和叉头框转录因子O3a(FOXO3a)的mRNA表达水平,Western Blot法检测胸主动脉SIRT1和FOXO3a蛋白表达水平。【结果】与空白组比较,模型组小鼠胸主动脉及血管内皮细胞病理变化明显,血清炎症因子TNF-α、ICAM-1和VCAM-1水平升高(P<0.05或P<0.01),胸主动脉SIRT1 mRNA和蛋白表达量降低(P<0.01),FOXO3a mRNA和蛋白表达量差异无统计学意义(P>0.05);与模型组比较,辛伐他汀组和艾灸组小鼠的胸主动脉及血管内皮细胞结构得到明显改善,血清TNF-α、ICAM-1、VCAM-1水平均降低(P<0.05),胸主动脉SIRT1 mRNA和蛋白表达量增加(P<0.05或P<0.01),FOXO3a mRNA和蛋白表达量差异均无统计学意义(P>0.05)。辛伐他汀组和艾灸组上述指标组间比较,差异均无统计学意义(P>0.05)。【结论】“温阳通脉”灸法可通过调控SIRT1/FOXO3a信号通路减轻炎症反应防治小鼠AS。

Endogenous hydrogen sulfide and ERK1/2-STAT3 signaling pathway may participate in the association between homocysteine and hypertension

Background Homocysteine(Hcy)is a risk factor for hypertension,although the mechanisms are poorly understood.Methods We first explored the relationship between Hcy levels and blood pressure(BP)by analyzing the clinical data of primary hypertensive patients admitted to our hospital.Secondly,we explored a rat model to study the effect of Hcy on blood pressure and the role of H2S.An hyperhomocysteinemia(HHcy)rat model was induced to explore the effect of Hcy on blood pressure and the possible mechanism.We carried out tissue histology,extraction and examination of RNA and protein.Finally,we conducted cell experiments to determine a likely mechanism through renin-angiotensin-aldosterone system(RAAS)and extracellular signal-regulated kinase 1/2(ERK1/2)signaling pathway.Results In primary hypertensive inpatients with HHcy,blood pressure was significantly higher as compared with inpatient counterparts lacking HHcy.In the rat model,blood pressure of the Wistar rats was significantly increased with increases in serum Hcy levels and decreased after folate treatment.Angiotensin converting enzyme 1(ACE1)expression in the Wistar Hcy group was enhanced comparing to controls,but was decreased in the Wistar folate group.Angiotensin II receptor type 1(AGTR1)levels in the kidney tissue increased in the Wistar folate group.Both serum H2S and kidney cystathionineγ-lyase decreased with elevated levels of serum Hcy.In vitro,increased concentrations and treatment times for Hcy were associated with increased expression of collagen type 1 and AGTR1.This dose and time dependent response was also observed for p-STAT3 and p-ERK1/2 expression.Conclusion Endogenous H2S might mediate the process of altered blood pressure in response to changes in serum Hcy levels,in a process that is partly dependent on activated RAAS and ERK1/2-STAT3 signaling pathway.