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.

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.

MiR-146a-5p targeting SMAD4 and TRAF6 inhibits adipogenensis through TGF-β and AKT/mTORC1 signal pathways in porcine intramuscular preadipocytes

Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a novel miRNA implicated in porcine IMF adipogenesis was found, and its effect and regulatory mechanism were further explored with respect to intramuscular preadipocyte proliferation and differentiation.Results: By porcine adipose tissue miRNA sequencing analysis, we found that miR-146a-5p is a potential regulator of porcine IMF adipogenesis. Further studies showed that miR-146a-5p mimics inhibited porcine intramuscular preadipocyte proliferation and differentiation, while the miR-146a-5p inhibitor promoted cell proliferation and adipogenic differentiation. Mechanistically, miR-146a-5p suppressed cell proliferation by directly targeting SMAD family member 4(SMAD4) to attenuate TGF-β signaling. Moreover, miR-146a-5p inhibited the differentiation of intramuscular preadipocytes by targeting TNF receptor-associated factor 6(TRAF6) to weaken the AKT/mTORC1 signaling downstream of the TRAF6 pathway.Conclusions: MiR-146a-5p targets SMAD4 and TRAF6 to inhibit porcine intramuscular adipogenesis by attenuating TGF-β and AKT/mTORC1 signaling, respectively. These findings provide a novel miRNA biomarker for regulating intramuscular adipogenesis to promote pork quality.

Elevated retinol binding protein 4 levels are associated with atherosclerosis in diabetic rats via JAK2/STAT3 signaling pathway

BACKGROUND Atherosclerosis is a major cause of mortality worldwide and is driven by multiple risk factors,including diabetes,which results in an increased atherosclerotic burden,but the precise mechanisms for the occurrence and development of diabetic atheroscerosis have not been fully elucidated.AIM To summarize the potential role of retinol binding protein 4(RBP4) in the pathogenesis of diabetic atheroscerosis,particularly in relation to the RBP4-Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)signaling pathway.METHODS Male Wistar rats were randomly divided into three groups,including a control group(NC group),diabetic rat group(DM group),and diabetic atherosclerotic rat group(DA group).The contents of total cholesterol(TC), high-density lipoprotein cholesterol(HDL-c), triglycerides(TG), low-density lipoprotein cholesterol(LDLc), fasting insulin(FINS),fasting plasma glucose,and hemoglobin A1 c(HbA1 c)were measured.Moreover,the adipose and serum levels of RBP4,along with the expression levels of JAK2, phosphorylated JAK2(p-JAK2), STAT3,phosphorylated STAT3(p-STAT3), B-cell lymphoma-2(Bcl-2), and Cyclin D1 in aortic tissues were also measured.Besides,homeostasis model assessment of insulin resistance(HOMA-IR) and atherogenic indexes(AI) were calculated.RESULTS Compared with the NC and DM groups,the levels LDL-c,TG,TC,FINS,HOMAIR,RBP4,and AI were upregulated,whereas that of HDL-c was downregulated in the DA group(P <0.05);the mRNA levels of JAK2,STAT3,Cyclin D1,and Bcl-2 in the DA group were significantly increased compared with the NC group and the DM group;P-JAK2,p-JAK2/JAK2 ratio,p-STAT3,p-STAT3/STAT3 ratio,Cyclin D1,and Bcl-2 at protein levels were significantly upregulated in the DA group compared with the NC group and DM group.In addition,as shown by Pearson analysis,serum RBP4 had a positive correlation with TG,TC,LDL-c,FINS,HbA1 C,p-JAK2,p-STAT3,Bcl-2,Cyclin D1,AI,and HOMA-IR but a negative correlation with HDL-c.In addition,multivariable logistic regression analysis showed that serum RBP4,p-JAK2,p-STAT3,and LDL-c were predictors of the presence of diabetic atherosclerosis.CONCLUSION RBP4 could be involved in the initiation or progression of diabetic atherosclerosis by regulating the JAK2/STAT3 signaling pathway.

Ramulus Cinnamomi extract attenuates neuroinflammatory responses via downregulating TLR4/MyD88 signaling pathway in BV2 cells

Ramulus Cinnamomi （RC）, a traditional Chinese herb, has been used to attenuate inflammatory responses. The purpose of this study was to investigate the effect of RC extract on lipopolysaccharide （LPS）-induced neuroinflammation in BV2 microglial cells and the underlying mechanisms involved. BV2 cells were incubated with normal medium （control group）, LPS, LPS plus 30 pg/mL RC extract, or LPS plus 100 pg/mL RC extract. The BV2 cell morphology was observed under an optical microscope and cell viability was detected by MTT assay. Nitric oxide level in BV2 cells was detected using Griess regents, and the levels of interleukin-6, interleukin-1 β, and tumor necrosis factor u in BV2 cells were determined by ELISA. The expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 proteins were detected by western blot assay. Compared with the LPS group, both 30 and 100 μg/mL RC extract had no significant effect on the viability of BV2 cells. The levels of nitric oxide, interleukin-6, interleukin-1β and tumor necrosis factor ct in BV2 cells were all significantly increased after LPS induction, and the levels were significantly reversed after treatment with 30 and 100 μg/mL RC extract. Furthermore, RC extract significantly inhibited the protein expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 in LPS-induced BV2 cells. Our findings suggest that RC extract alleviates neuroinflammation by downregulating the TLR4/MyD88 signaling pathway.

Yiqi Yangyin and Huatan Quyu granule can improve skeletal muscle energy metabolism in a type 2 diabetic rat model by promoting the AMPK/SIRT/PGC-1α signalling pathway

Objective:To investigate how Yiqi Yangyin and Huatan Quyu granule (YYHO) improves skeletal muscle insulin resistance in a type 2 diabetic rat model and to discover whether the molecular mechanism is related to the promotion of the AMPK/SIRT/PGC-1α signalling pathway.Methods:Rats were randomly divided into 4 groups:the normal group,the model group,the YYHQ granule group,and the pioglitazone group.The type 2 diabetic rat model was established by feeding a high-fat diet for 5 weeks along with a single intraperitoneal injection of 30 mg/kg streptozotocin (STZ).After modelling successfully,the appropriate drug was intragastrically administered to diabetic rats for 2 weeks,once per day.The YYHQ granule group was given a dose of 4.8 g/kg body weight per day,the pioglitazone group was given a dose of 1.35 mg/kg body weight per day.The doses for both groups were equivalent to the clinical equivalent dose based on a previous study.Other groups were gavaged with the same amount of saline water.Body weight,food intake,water intake,urine volume and grip strength were recorded weekly.The fasting blood glucose(FBG) was determined weekly using blood glucose test strips.The related glucose and lipid metabolism indexes,e.g.,fasting insulin (Fins),glycated haemoglobin (GHb),HOMA-IR,ISI,triglycerides (TG),total cholesterol (TC),high-density lipoprotein cholesterol (HDL-C),low-density lipoprotein cholesterol (LDL-C) and free fatty acid (FFA),were determined using biochemical method.The mRNA expression levels of adenosine monophosphate-activated protein kinase (AMPK),peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α),carnitine palmitoyl transterase-1 (CPT-1),Sirtuin 1 (SIRT1),and Sirtuin 3 (SIRT3) were assessed using quantitative real-time PCR (qRT-PCR).The protein expression levels of creatine kinase (CK),Ca2+ ATPase,α-Actin,AMPK,PGC-1α and CPT-1 were determined using enzyme-linked immunosorbent assay method (ELISA).Results:Body weight decreased significantly (P <.01),food intake,water intake and urine volume increased significantly (P <.01),and grip strength decreased significantly (P <.01) in the model group compared with the normal group.The levels of FBG,Fins,GHb and HOMA-IR increased significantly (P <.01),and the ISI decreased significantly (P <.01) in the model group.The levels of TG,TC,LDL-C and FFA increased significantly (P <.05 or P <.01),and the level of HDL-C decreased significantly (P <.05) in the model group.These changes were reversed after treatment with YYHQ granule or pioglitazone.Compared with the model group,the YYHQ granule and pioglitazone groups significantly improve body weight,water intake and urine volume (P <.05 or P <.01),however,both treatments had no significant effect on food intake (P >.05).The levels of FBG,Fins,GHb,HOMA-IR and ISI were improved significantly (P <.01) and the levels of TG,TC and LDL-C were improved significantly (P <.05 or P <.01),however,both treatments had no significant effect on the levels of HDL-C and FFA (P >.05).Further results indicated that YYHQ granule significantly decreased the mRNA expression of AMPK,PGC-1α,CPT-1,SIRT1 and SIRT3 in skeletal muscle (P <.01) and the pioglitazone group showed similar effects;moreover,the protein expression levels of CK,Ca2+ATPase,α-Actin,AMPK,PGC-1α and CPT-1 in skeletal muscle significantly decreased (P <.01),however,pioglitazone had no significant effect on CK and α-Actin (P >.05).Conclusion:The possible molecular mechanism of YYHQ granule improving skeletal muscle insulin resistance in a type 2 diabetic rat model may be related to the stimulation of energy metabolism in skeletal muscle via the AMPK/SIRT/PGC-1α signalling pathway.

Correlation between receptor-interacting protein 140 expression and directed differentiation of human embryonic stem cells into neural stem cells

Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.

Danshensu Ameliorates Cardiac Ischaemia Reperfusion Injury through Activating Sirt1/Fox01/Rab7 Signal Pathway

Objective:To explore the specific molecular mechanisms of Danshensu(DSS)in the treatment of ischemia reperfusion injury(IRI).Methods:IRI model was established with isolated rat hearts by performing global ischaemia for 30 min,and then followed by 60 min reperfusion.Also,H9C2 cells were subjected to 4-h hypoxia followed by 3-h reoxygenation.Then 10|i mol/L DSS were added in the reperfusion/reoxygenation step to intervene IRI.Cardiac function,structural change and apoptosis were respectively tested by Langendorff System,hematoxylin and eosin(HE)and terminal-deoxynucleotidyl transferase mediated nick endabeling(TUNEL)stainings.Then lactate dehydrogenase(LDH),cardiac troponin T(cTnT),reactive oxygen species(ROS),superoxide dismutase(SOD)and glutathione peroxidase(GSH-PX)were detected by enzyme-linked immunosorbent assay(ELISA).Sirt1/FoxO1/Rab7 Signal Pathway was monitored at both protein and mRNA levels.Results:The results showed that IRI not only greatly attenuated cardiac function(LVDP and±dp/dtmax,P<0.01,P<0.05)and increased the level of the marker enzymes(cTnT,LDH,P<0.01)from the coronary effluents,but also markedly induced changes in the structure of cardiomyocytes and contributed to apoptosis,which were mediated by boosted en doge nous ROS.However,after treatment with DSS all above indexes were improved,which was related to activating Sirt1/FoxO1/Rab7 signal pathway accompanied with the enhancement of antioxidant defense system,such as SOD and GSH-PX.Conclusion:DSS is able to protect hearts from IRI,which may be attributable to inhibiting excessive ROS through Sirt1/FoxO1/Rab7 signaling.

Ginsenoside Rb1 Protects Human Umbilical Vein Endothelial Cells against High Glucose-Induced Mitochondria-Related Apoptosis through Activating SIRT3 Signalling Pathway

Objective:To investigate whether ginsenoside Rb1(Rb1)can protect human umbilical vein endothelial cells(HUVECs)against high glucose-induced apoptosis and examine the underlying mechanism.Methods:HUVECs were divided into 5 groups:control group(5.5 mmol/L glucose),high glucose(HG,40 mmol/L)treatment group,Rb1(50μmol/L)treatment group,Rb1 plus HG treatment group,and Rb1 and 3-(1 H-1,2,3-triazol-4-yl)pyridine(3-TYP,16μmol/L)plus HG treatment group.Cell viability was evaluated by cell counting kit-8 assay.Mitochondrial and intracellular reactive oxygen species were detected by Mito Sox Red mitochondrial superoxide indicator and dichloro-dihydro-fluorescein diacetate assay,respectively.Annexin V/propidium iodide staining and fluorescent dye staining were used to measure the apoptosis and the mitochondrial membrane potential of HUVECs,respectively.The protein expressions of apoptosis-related proteins[Bcl-2,Bax,cleaved caspase-3 and cytochrome c(Cyt-c)],mitochondrial biogenesis-related proteins[proliferator-activated receptor gamma coactivator 1-alpha,nuclear respiratory factor-1 and mitochondrial transcription factor A],acetylation levels of forkhead box O3 a and SOD2,and sirtuin-3(SIRT3)signalling pathway were measured by immunoblotting and immunoprecipitation.Results:Rb1 ameliorated survival in cells in which apoptosis was induced by high glucose(P<0.05 or P<0.01).Upon the addition of Rb1,mitochondrial and intracellular reactive oxygen species generation and malondialdehyde levels were decreased(P<0.01),while the activities of antioxidant enzymes were increased(P<0.05 or P<0.01).Rb1 preserved the mitochondrial membrane potential and reduced the release of Cyt-c from the mitochondria into the cytosol(P<0.01).In addition,Rb1 upregulated mitochondrial biogenesis-associated proteins(P<0.01).Notably,the cytoprotective effects of Rb1 were correlated with SIRT3 signalling pathway activation(P<0.01).The effect of Rb1 against high glucose-induced mitochondria-related apoptosis was restrained by 3-TYP(P<0.05 or P<0.01).Conclusion:Rb1 could protect HUVECs from high glucose-induced apoptosis by promoting mitochondrial function and suppressing oxidative stress through the SIRT3 signalling pathway.

Association of overexpression of TIF1γ with colorectal carcinogenesis and advanced colorectal adenocarcinoma

AIM:To determine the expression and clinical significance of transcriptional intermediary factor 1 gamma (TIF1γ),Smad4 and transforming growth factor-beta (TGFβR) across a spectrum representing colorectal cancer (CRC) development.METHODS:Tissue microarrays were prepared from archival paraffin embedded tissue,including 51 colorectal carcinomas,25 tubular adenomas (TA) and 26 HPs,each with matched normal colonic epithelium.Immunohistochemistry was performed using antibodies against TIF1γ,Smad4 and TGFβ RⅡ.The levels of expression were scored semi-quantitatively (score 0-3 or loss and retention for Smad4).RESULTS:Overexpression of TIF1γ was detected in 5/26 (19%) HP;however,it was seen in a significantly higher proportion of neoplasms,15/25 (60%) TAs and 24/51 (47%) CRCs (P<0.05).Normal colonic mucosa,HP,and TAs showed strong Smad4 expression,while its expression was absent in 22/51 (43%) CRCs.Over-expression of TGFβ RⅡ was more commonly seen in neoplasms,13/25 (52%) TAs and 29/51 (57%) CRCs compared to 9/26 (35%) HP (P<0.05).Furthermore,there was a correlation between TIF1γ overexpression and Smad4 loss in CRC (Kendall tau rank correlation value=0.35,P<0.05).The levels of TIF1γ overexpression were significantly higher in stage Ⅲ than in stage Ⅰ and Ⅱ CRC (P<0.05).CONCLUSION:The findings suggest that over-expression of TIF1γ occurs in early stages of colorectal carcinogenesis,is inversely related with Smad4 loss,and may be a prognostic indicator for poor outcome.

L-leucine stimulates glutamate dehydrogenase activity and glutamate synthesis by regulating mTORC1/SIRT4 pathway in pig liver

The liver is the most essential organ for the metabolism of ammonia, in where most of ammonia is removed by urea and glutamine synthesis. Regulated by leucine, glutamate dehydrogenase(GDH) catalyzes the reversible inter-conversion of glutamate to ammonia. To determine the mechanism of leucine regulating GDH, pigs weighing 20 ± 1 kg were infused for 80 min with ammonium chloride or alanine in the presence or absence of leucine. Primary pig hepatocytes were incubated with or without leucine. In the in vivo experiments with either ammonium or alanine as the nitrogen source, addition of leucine significantly inhibited ureagenesis and promoted the production of glutamate and glutamine in the perfused pig liver(P < 0.05). Similarly, leucine stimulated GDH activity and inhibited sirtuin4(SIRT4)gene expression(P < 0.01). Leucine could also activate mammalian target of rapamycin complex 1(m TORC1) signaling(P < 0.05), as evidenced by the increased phosphorylation levels of ribosomal protein S6 kinase 1(S6 K1) and ribosomal protein S6(S6). Interestingly, the leucine-induced m TORC1 pathway activation suitably correlated with increased GDH activity and decreased expression of SIRT4.Similar results were observed in primary cultured hepatocytes. Notably, leucine exerted no significant change in GDH activity in SIRT4-deficient hepatocytes(P > 0.05), while m TORC1 signaling was activated.Leucine exerted no significant changes in both GDH activity and SIRT4 gene expression in rapamycin treated hepatocytes(P > 0.05). In conclusion, L-leucine increases GDH activity and stimulates glutamate synthesis from different nitrogen sources by regulating m TORC1/SIRT4 pathway in the liver of pigs.

Protective Effect of SGLT2 Inhibitor on D-Galactose-Induced Senescence in Mice and Its Mechanism

Objective: To observe the cerebral protective effect of dagliflozin, a sodium-glucose co-transport protein 2 (SGLT2) inhibitor, in aging mice and to explore its molecular mechanism. Methods: 1. 66 male C57BL/6 mice were divided into control group (13) and model group (53), and the model group was moulded by subcutaneous injection of D-galactose into the back of the neck, while the control group was treated with equal amount of saline for 8 weeks. The weight of each group of mice was observed and recorded every 7 days, and two groups of mice were randomly selected for frozen sections of brain tissue at the end of the modelling period to verify the aging model. 2. After the aging model was successfully established, the aging groups were divided into 5 groups: model group, dagliflozin-treated group (high and low dose), and dagliflozin + ex527-inhibited group (high and low dose). Fasting blood glucose was measured in each group every 2 weeks for 8 weeks. At the end of treatment, Morris water maze was performed at the end of the treatment. After execution of the mice, the organ indices of heart, brain, liver, kidney and spleen were measured;the levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in serum were determined. Results: After the successful establishment of the aging model, it was found that during the treatment phase of dagliflozin. 1) The organ indices of mice in the aging group were significantly lower than those of other groups, and no significant hypoglycemia was observed throughout the treatment process. 2) In the water maze test, mice in the aging group had a significantly longer latency in the plateau phase compared to the control and treatment groups, while the number of times the mice crossed the original plateau and the percentage of time spent exploring the original plateau quadrant were reduced after the plateau was removed. 3) The nerve cells in the aging mice were disorganized and the nuclei of the mice were deeply stained;the dagliflozin group improved the morphological changes in the brain of aging mice. 4) In addition, compared with the control mice, the serum MDA level was significantly increased and the antioxidant enzyme SOD activity was significantly decreased in the aging group, while compared with the aging group, dagliflozin significantly decreased the MDA level and increased the SOD activity. 5) The expression of SIRT1 and PGC-1α was significantly upregulated in the low and high doses of dagliflozin compared to the aging group. Conclusion: The present study suggests that dagliflozin can delay organ aging, improve the learning and memory ability of aging mice, and exert antioxidant effects, probably through upregulating the SIRT1/PGC-1α signaling pathway.

白藜芦醇对大鼠脓毒症心肌病铁死亡的影响及机制

目的探讨白藜芦醇对大鼠脓毒症心肌病铁死亡的影响及作用机制。方法采用盲肠结扎穿孔法制备脓毒症心肌病模型,将48只6~8周龄健康SD大鼠随机分为假手术组、模型对照组、白藜芦醇组、Ex527(SIRT1抑制剂)组。在不同组别中,通过心肌苏木精-伊红(HE)染色、乳酸脱氢酶(LDH)、肌酸激酶同工酶(CK-MB)观察心肌损伤程度,透射电镜观察心脏线粒体变化,试剂盒及免疫荧光检测铁离子浓度、还原型谷胱甘肽(GSH)、丙二醇(MDA)、活性氧自由基(ROS)铁死亡相关信号表达,Western blotting方法检测心肌SIRT1、GPX4、FTH-1蛋白表达水平。结果与模型对照组比较,白藜芦醇组可明显改善心肌损伤程度,减轻线粒体铁死亡改变,显著抑制铁死亡相关信号表达(P<0.05),增加SIRT1、GPX4、FTH-1蛋白表达水平(P<0.05),而使用Ex527预处理大鼠可逆转上述改变。结论白藜芦醇通过SIRT1/GPX4信号途径抑制心肌铁死亡,改善脓毒症心肌病,其机制与减少ROS产生、减轻线粒体损伤密切相关。

MicroRNA-23a reduces lipopolysaccharide-induced cellular apoptosis and inflammatory cytokine production through Rho-associated kinase 1/sirtuin-1/nuclear factor-kappa B crosstalk

Background:MicroRNAs are closely associated with the progression and outcomes of multiple human diseases,including sepsis.In this study,we examined the role of miR-23a in septic injury.Methods Lipopolysaccharide(LPS)was used to induce sepsis in a rat model and H9C2 and HK-2 cells.miR-23a expression was evaluated in rat myocardial and kidney tissues,as well as H9C2 and HK-2 cells.A miR-23a mimic was introduced into cells to identify the role of miR-23a in cell viability,apoptosis,and the secretion of inflammatory cytokines.Furthermore,the effect of Rho-associated kinase 1(ROCK1),a miR-23a target,on cell damage was evaluated,and molecules involved in the underlying mechanism were identified.Results:In the rat model,miR-23a was poorly expressed in myocardial(sham vs.sepsis 1.00±0.06 vs.0.27±0.03,P<0.01)and kidney tissues(sham vs.sepsis 0.27±0.03 vs.1.00±0.06,P<0.01).Artificial overexpression of miR-23a resulted in increased proliferative activity(DNA replication rate:Control vs.LPS vs.LPS+Mock vs.LPS+miR-23a:H9C2 cells:34.13±3.12 vs.12.94±1.21 vs.13.31±1.43 vs.22.94±2.26,P<0.05;HK-2 cells:15.17±1.43 vs.34.52±3.46 vs.35.19±3.12 vs.19.87±1.52,P<0.05),decreased cell apoptosis(Control vs.LPS vs.LPS+Mock vs.LPS+miR-23a:H9C2 cells:11.39±1.04 vs.32.57±2.29 vs.33.08±3.12 vs.21.63±2.35,P<0.05;HK-2 cells:15.17±1.43 vs.34.52±3.46 vs.35.19±3.12 vs.19.87±1.52,P<0.05),and decreased production of inflammatory cytokines,including interleukin-6(Control vs.LPS vs.LPS+Mock vs.LPS+miR-23a:H9C2 cells:59.61±5.14 vs.113.54±12.30 vs.116.51±10.69 vs.87.69±2.97 ng/mL;P<0.05,F=12.67,HK-2 cells:68.12±6.44 vs.139.65±16.62 vs.143.51±13.64 vs.100.82±9.74 ng/mL,P<0.05,F=9.83)and tumor necrosis factor-α(Control vs.LPS vs.LPS+Mock vs.LPS+miR-23a:H9C2 cells:103.20±10.31 vs.169.67±18.84 vs.173.61±15.91 vs.133.36±12.32 ng/mL,P<0.05,F=12.67,HK-2 cells:132.51±13.37 vs.187.47±16.74 vs.143.51±13.64 vs.155.79±15.31 ng/mL,P<0.05,F=9.83)in cells.However,ROCK1 was identified as a miR-23a target,and further up-regulation of ROCK1 mitigated the protective function of miR-23a in LPS-treated H9C2 and HK-2 cells.Moreover,ROCK1 suppressed sirtuin-1(SIRT1)expression to promote the phosphorylation of nuclear factor-kappa B(NF-κB)p65,indicating the possible involvement of this signaling pathway in miR-23a-mediated events.Conclusion:Our results indicate that miR-23a could suppress LPS-induced cell damage and inflammatory cytokine secretion by binding to ROCK1,mediated through the potential participation of the SIRT1/NF-κB signaling pathway.

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.

Use of network pharmacology and molecular docking to explore the potential mechanism governing the efficacy of Jinhuaqinggan granules in the treatment of novel coronavirus-induced pneumonia

Background:Now that the epidemic of new coronavirus pneumonia(corona virus disease 2019)is spreading all over the world,Jinhuaqinggan granules in the Chinese treatment plan has been proved to be an effective Chinese patent medicine for the treatment of corona virus disease 2019.Methods:This study aims to clarify the possible therapeutic mechanism governing the efficacy of Jinhuaqinggan granules in the treatment of corona virus disease 2019,through using network pharmacology and molecular docking.During the analysis,227 active components were obtained and screened by using the ADME method.Furthermore,282 Jinhuaqinggan granule targets and 56 common targets with corona virus disease 2019 were gathered from various databases.Then the protein-protein interaction network of Jinhuaqinggan granules and corona virus disease 2019 targets were constructed and 6 core targets were selected through network topology analysis.In addition,A total of 262 biological function annotation entries(P<0.01)and 101 pathways(P<0.01)were obtained by gene ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis.Results:Molecular docking showed that quercetin,luteolin,kaempferol,wogonin and naringin had an affinity for SARS-CoV-23CL hydrolase and angiotensin-converting enzyme 2.Conclusion:corona virus disease 2019 can be prevented by the primary targets of Jinhuaqinggan granules.The most important bioactive components in Jinhuaqinggan granules-quercetin,naringenin,luteolin and wogonin-can play antiviral effect,anti-inflammatory storm,regulate immunity by regulating signal transducers and activators of transcription 1,interleukin 4,interferon-γ,heme oxygenase 1 and acting on the lipopolysaccharide response,toll-like receptor signaling pathway,mitogen-activated protein kinase signaling pathway,etc.

Transferrin receptor-targeted immunostimulant for photodynamic immunotherapy against metastatic tumors through β-catenin/CREB interruption

The immunosuppressive phenotype of tumor cells extensively attenuates the immune activation effects of traditional treatments.In this work,a transferrin receptor(TfR)targeted immunostimulant(PTI)is fabricated for photodynamic immunotherapy against metastatic tumors by interrupting β-catenin signal pathway.To synthesize PTI,the photosensitizer conjugated TfR targeting peptide moiety(Palmitic-K(PpIX)-HAIYPRH)is unitized to encapsulate the transcription interrupter of ICG-001.On the one hand,the recognition of PTI and TfR can promote drug delivery into tumor cells to destruct primary tumors through photodynamic therapy and initiate an immunogenic cell death with the release of tumorassociated antigens.On the other hand,PTI will interrupt the binding between b-catenin andcAMP response element-binding protein(CREB),regulating the gene transcription to downregulate programmed death ligand 1(PD-L1)while upregulating CeC motif chemokine ligand 4(CCL4).Furthermore,the elevated CCL4 can recruit the dendritic cells to present tumor-specific antigens and promote T cells activation and infiltration,and the downregulated PD-L1 can avoid the immune evasion of tumor cells and activate systemic anti-tumor immunity to eradicate lung metastasis.This work may inspire the development of antibody antibody-free strategy to activate systemic immune response in consideration of immunosuppressive conditions.