microRNA-26a inhibits extracellular matrix synthesis in high glucose-induced renal tubular epithelial cells by regulating ferroptosis / 安徽医科大学学报

Objective To investigate the effect and possible mechanism of microRNA-26a(miR-26a)on the syn-thesis of extracellular matrix(ECM)induced by high glucose(HG)in renal tubular epithelial cells(RTECs).Methods A model of diabetic kidney disease(DKD)was constructed by inducing RTECs with HG.MiR-26a was overexpressed in HG-induced RTECs,and RT-qPCR and Western blot were used to assess the effects of miR-26a on ECM synthesis and ferroptosis-related markers in HG-treated RTECs.Ferrostatin(Fer-1)was used to inhibit ferroptosis in the DKD model,and its impact on ECM synthesis was evaluated.RT-qPCR and Western blot were performed to measure ferroptosis-related markers,and fluorescence microscopy was used to observe the intensity of reactive oxygen species(ROS).Results Compared with the control group,the expression of miR-26a decreased in HG-treated cells,while the expression levels of ECM synthesis-related indexes fibronectin and collagen Ⅰ in-creased.After overexpressing miR-26a,the HG+miR-26a group showed a significant increase in miR-26a expres-sion and a decrease in fibronectin and collagen Ⅰ expression compared to the HG group.In terms of ferroptosis,the protein and mRNA expression of SLC7A11 and GPX4 significantly decreased,the expression of TFR-1 and AC-SL4 significantly increased,and the fluorescence intensity of ROS was significantly enhanced in the HG group com-pared with the control group.Inhibition of ferroptosis in the HG+Fer-1 group resulted in significant changes in fer-roptosis and ECM synthesis-related indicators expression levels compared to the HG group.Furthermore,re-expres-sion of miR-26a in the HG+miR-26a led to significant changes in ferroptosis-related indicators expression levels and decreased ROS fluorescence intensity compared to the HG group.Conclusions In HG-induced RTECs,miR-26a inhibits the occurrence of ferroptosis,thus reducing ECM synthesis.

Expression and role of triggering receptor expressed on myeloid cells 2 in high glucose-treated microglia / 基础医学与临床

Objective To explore the expression of triggering receptor expressed on myeloid cells 2(TREM2)in high-glucose microglia and to investigate the role of TREM2 in the proliferation,migration and phagocytosis of high-glucose microglia.Methods Microglia cells were divided into control group and high-glucose treatment group(67.5 mmol/L glucose,24 h).The microglia cells were counted and the expression of Iba1 and TREM2 was de-tected.TREM2 siRNA was transfected to detect the proliferation and migration of microglia.The amyloid β-peptide(Aβ)with a fluorescent tag was added to observe the phagocytosis of Aβ by microglia.Results Compared to normal microglia,the number of microglia significantly decreased after high-glucose treatment(P＜0.001),while the ex-pression of TREM2 and Iba1 markedly increased(P＜0.001).High glucose and TREM2 did not affect the prolifer-ation of microglia.Compared to the normal group,the migration of microglia significantly decreased after high-glu-cose treatment(P＜0.05)and TREM2 did not affect the migration ability of high-glucose microglia.Compared to the normal group,the phagocytosis of Aβ by microglia significantly decreased in the high-glucose treated group(P＜0.001).Furthermore,TREM2 knockdown further decreased the phagocytosis of Aβ by high-glucose microglia(P＜0.001).Conclusions The expression of TREM2 in microglia significantly increases after high-glucose treat-ment,which significantly affects phagocytosis of Aβ by microglia.

Effect of glycyrrhizin on inflammatory factors and fibrotic factors in high glucose-induced glomerular mesangial cells / 解放军医学杂志

Objective To investigate the effect of glycyrrhizic acid(GA)on the inflammatory and fibrotic factors in high glucose-induced glomerular mesangial cells(SV40 MES13).Methods Cultured mouse SV40 MES13 were divided into normal group(NG,5.6 mmol/L glucose),high glucose group(30 mmol/L glucose)and HG+GA group(30 mmol/L glucose+200 μmol/L GA).The expression levels of inflammatory cytokines interleukin-1β(IL-1β),tumor necrosis factor-α(TNF-α),IL-6,IL-8 and α-smooth muscle actin(α-SMA)in different groups were detected by Western blotting.The fluorescence intensity of IL-1β,TNF-α and α-SMA in different groups were detected by immunofluorescence.The levels of IL-1β,TNF-α,IL-6 and IL-8 in the culture supernatant of different populations were detected by enzyme-linked immunosorbent assay(ELISA).Results The protein expressions of IL-1β,TNF-α,IL-6,IL-8 and α-SMA in HG group were significantly higher than those in NG group(P<0.01);Compared with HG group,the protein expression levels of IL-1β,TNF-α,IL-6,IL-8 and α-SMA decreased significantly in HG+GA group(P<0.05).The fluorescence intensity of inflammatory cytokines IL-1β,TNF-α and α-SMA increased in HG group than those in NG group(P<0.05);While compared with the HG group,the fluorescence intensity of IL-1β,TNF-α and α-SMA in HG+GA group decreased markedly(P<0.05).The experimental results of ELISA showed that compared with NG group,the levels of IL-1β,IL-6,TNF-α and IL-8 in cell supernatent increased in HG group(P<0.01);while the levels of IL-1β,TNF-α,IL-6,IL-8 in HG+GA group significantly lower than those in HG group(P<0.05).Conclusion Glycyrrhizic acid has certain inhibitory effect on high glucose-induced inflammatory factors and fibrotic factors in glomerular mesangial cells,which may play an important role in prevention of diabetic nephropathy.

Polycaprolactone-polydopamine-AOPDM1 scaffold promotes bone formation in a high-glucose environment / 中国组织工程研究

BACKGROUND:Oral and maxillofacial bone tissue defects can seriously affect the physical and mental health of patients.When bone defects occur in diabetic patients,bone metabolism disorders caused by abnormal blood sugar make it more difficult to repair and treat. OBJECTIVE:To attempt to apply AOPDM1,a polypeptide with potential bioactivity to the osteogenic treatment of diabetic patients. METHODS:In normal or high-glucose environment,different concentrations of AOPDM1 were used to interfere with mouse bone marrow mesenchymal stem cells,and cell proliferation,alkaline phosphatase activity,mineralization nodules formation and osteogenic differentiation gene expression were detected.The polycaprolactone scaffold was prepared by electrospinning technology,and the scaffold was modified by polydopamine to prepare the polycaprolactone-polydopamine composite scaffold.Finally,the scaffolds were placed in AOPDM1 solution to prepare polycaprolactone-polydopamine-AOPDM1 scaffolds.The water contact angle and mechanical properties of the scaffolds were tested in the three groups.In normal or high-glucose environment,the three groups of scaffolds were co-cultured with mouse bone marrow mesenchymal stem cells,respectively,and cell adhesion,alkaline phosphatase activity and osteopontin expression were detected. RESULTS AND CONCLUSION:(1)Compared with normal environment,high-glucose environment inhibited the proliferation of bone marrow mesenchymal stem cells.In the same environment,AOPDM1 could promote the proliferation of mouse bone marrow mesenchymal stem cells.When AOPDM1 concentration was the same,alkaline phosphatase activity,mineralization ability and mRNA expression of type Ⅰ collagen,osteopontin,alkaline phosphatase,and Runx2 of bone marrow mesenchymal stem cells were decreased in high-glucose environment compared with normal environment.Under the same environment,AOPDM1 could improve the alkaline phosphatase activity,mineralization ability,and mRNA expression of type Ⅰ collagen,osteopontin,alkaline phosphatase and Runx2 of bone marrow mesenchymal stem cells.(2)The hydrophilicity of polycaprolactone-polydopamine scaffold and polycaprolactone-polydopamine-AOPDM1 scaffold was higher than that of polycaprolactone scaffold(P<0.001),and there was no significant difference in tensile strength and elastic modulus among the three groups(P>0.05).Compared with the other two groups of scaffolds,the cells on the polycaprolactone-polydopamine-AOPDM1 scaffold had better adhesion morphology.When the scaffolds were identical,compared with normal environment,high-glucose environment inhibited alkaline phosphatase activity and osteopontin expression of bone marrow mesenchymal stem cells.When the environment was the same,the alkaline phosphatase activity and osteopontin expression of bone marrow mesenchymal stem cells on the polycaprolactone-polydopamine-AOPDM1 scaffold were higher than those on the other two scaffolds.(3)The above results prove that polycaprolactone-polydopamine-AOPDM composite scaffold can promote the osteogenic properties of bone marrow mesenchymal stem cells in high-glucose environment.

Berberine promotes osteogenic differentiation of bone marrow mesenchymal stem cells in a high-glucose environment / 中国组织工程研究

BACKGROUND:The implant osseointegration rate of patients with diabetes is low,and the failure rate is high,which seriously affects the quality of life.It is urgent to improve the implant osseointegration of patients with diabetes by effective means to elevate the success rate.Exploring the effect of berberine on the osteogenic differentiation of bone marrow mesenchymal stem cells under a high-glucose environment and its specific mechanism will provide effective theoretical support for solving the above problems. OBJECTIVE:To explore the effect of natural extract berberine on the osteogenic differentiation of rat bone marrow mesenchymal stem cells under the high-glucose microenvironment. METHODS:Bone marrow mesenchymal stem cells of SD rats were cultured by the whole bone marrow adherence method.CCK-8 assay was used to detect the effects of different concentrations of berberine on the proliferation of bone marrow mesenchymal stem cells under the high-glucose environment and to screen out the optimal berberine concentration.The expressions of Runx2 and Osx were detected by alkaline phosphatase activity,alicarin red staining and PCR to determine the effect of berberine on osteogenic differentiation of bone marrow mesymal stem cells under the high-glucose environment.To further explore the underlying mechanism,we introduced the AMPK-specific inhibitor Dorsomorphin and used a DCFH-DA reactive oxygen species fluorescent probe to examine reactive oxygen species levels.The p-AMPK expression was also determined by western blot assay. RESULTS AND CONCLUSION:(1)10 μmol/L was the optimal concentration of berberine to promote bone marrow mesenchymal stem cell proliferation.(2)Alberberine promoted alkaline phosphatase viability of bone marrow mesenchymal stem cells and mineralized nodule formation in a high-glucose microenvironment.(3)Alberberine promoted the expression of Runx2 and OSx in a high-glucose microenvironment.(4)Alberensine effectively inhibited the reactive oxygen species level of bone marrow mesenchymal stem cells in a high-glucose environment.(5)The effects of berberine on promoting bone marrow mesenchymal stem cell osteogenesis and inhibition of reactive oxygen species were reversed by the AMPK inhibitor.(6)Berberine activated AMPK and promoted p-AMPK expression.(7)The above results indicate that berberine(10 μmol/L)promotes the osteogenic differentiation of bone marrow mesenchymal stem cells in a high-glucose environment by activating AMPK and reducing intracellular reactive oxygen species levels.

Effect of Icariin Regulating mTOR/Akt/CREB Pathway on High Glucose Induced Autophagy and Apoptosis in Podocytes / 医药导报

Objective To investigate the effects of icariin on high glucose-induced autophagy and apoptosis of podocytes,and the regulating effects on mammalian target of rapamycin(mTOR)/serine-threonine kinase(Akt)/cyclic adenosine monophosphate response element binding protein(CREB)pathway.Methods The mouse podocytes MPC5 were taken and divided into five groups:normal control group(5.5 mmol·L-1 glucose),high glucose group(30 mmol·L-1 glucose),icariin group(30 mmol·L-1glucose+5 μmol·L-1icariin),GDC-0349 group(30 mmol·L-1glucose+50 μmol·L-1 GDC-0349),icariin+GDC-0349 group(30 mmol·L-1 glucose+5 μmol·L-1 icariin+50 μmol·L-1 GDC-0349).Cultured for 48 hours,the tetramethylazozolium salt method was used to detect the viability of MPC5 cells;acridine orange staining was used to observe the autophagy of MPC5 cells;apoptosis of MPC5 cells was detected by flow cytometry;Western blotting was used to detect the expression of autophagy[microtubule associated protein one light chain 3(LC3)II,LC3Ⅰ,autophagy-related protein(Beclin-1)],apoptosis[Bcl-2 related X protein(Bax),B cell lymphoma-2(Bcl-2)]and mTOR/Akt/CREB pathway-related proteins of MPC5 cells.Results Compared with the normal control group,the cell viability,expression levels of Bcl-2,phosphorylated mTOR(p-mTOR)/mTOR,phosphorylated Akt(p-Akt)/Akt,phosphorylated CREB(p-CREB)/CREB protein of MPC5 cells in the high glucose group were significantly decreased(P＜0.05),the autophagy ability was enhanced,the autophagosome showed orange fluorescence,and the apoptosis rate,LC3Ⅱ/LC3Ⅰ,Beclin-1,Bax protein expression levels were significantly increased(P＜0.05).Compared with the high glucose group,the cell viability,LC3Ⅱ/LC3Ⅰ,Beclin-1,Bcl-2,p-mTOR/mTOR,p-Akt/Akt,p-CREB/CREB protein expression levels of MPC5 cells in icariin group were significantly increased,the autophagy ability was further enhanced,the number of autophagosomes was increased,the autophagosomes showed brick red fluorescence(P＜0.05),the apoptosis rate and Bax protein expression level were significantly decreased(P＜0.05),and the cell viability,LC3Ⅱ/LC3Ⅰ,Beclin-1,Bcl-2,p-mTOR/mTOR,p-Akt/Akt and p-CREB/CREB proteins expression levels of MPC5 cells in GDC-0349 group were significantly decreased,the autophagy ability was weakened,the number of autophagosomes was reduced,the autophagosomes showed orange fluorescence(P＜0.05),and the apoptosis rate and Bax protein expression level were significantly increased(P＜0.05);icariin+GDC-0349 could reverse the effect of icariin on high glucose induced MPC5 cells(P＜0.05).Conclusion Icariin promotes elevated glucose-induced podocyte autophagy and inhibits apoptosis by activating the mTOR/Akt/CREB pathway.

Impact of evodiamine on the proliferation，migration and invasion of trophoblastic cells induced by high glucose and its mechanism / 中国药房

OBJECTIVE To investigate the impact of evodiamine on the proliferation， migration and invasion abilities of trophoblastic cells induced by high glucose and its potential mechanism based on advanced glycation end products （AGE）/receptor for advanced glycation end products （RAGE） signaling pathway. METHODS Human trophoblastic cells HTR-8/SVneo were divided into control group， high glucose group， evodiamine low-dose group （2 μmol/L）， evodiamine high-dose group （4 μmol/L）， pc-NC group （transfected with pc-NC plasmid+4 μmol/L evodiamine）， and pc-RAGE group （transfected with pc-RAGE plasmid+ 4 μmol/L evodiamine）. Cells in all groups except for the control group were cultured in a high sugar （25 mmol/L glucose） environment， and cells in all groups except for the control group and the model group were transfected with the corresponding plasmids and/or received the corresponding drug interventions. The survival rate， apoptotic rate， scratch healing rate， and invasion number， as well as the protein and mRNA expressions of AGE， RAGE， nuclear factor- κB p65 （NF- κB p65）， matrix metalloproteinase-2 （MMP-2）， and MMP-9 were examined in each group. RESULTS Compared with the control group， the cell survival rate， scratch healing rate， invasions number， and the mRNA and protein expressions of MMP-2 and MMP-9 in the high glucose group significantly decreased （P＜0.05）， while the apoptotic rate， the mRNA and protein expressions of AGE and RAGE， the mRNA expression of NF-κB p65， and the phosphorylation level of NF-κB p65 protein significantly increased （P＜0.05）； compared with the high glucose group， the above indexes of cells in evodiamine low-dose and high-dose groups were significantly improved， and the effect of the high-dose group was significantly better than that of the low-dose group （P＜0.05）； overexpression of RAGE attenuated the ameliorative effect of evodiamine onthe above indexes in high glucose-induced trophoblast cells （except for AGE mRNA and protein） （P＜0.05）. CONCLUSIONS Evodiamine can promote the proliferation， migration and invasion of high glucose-induced trophoblast cells and ameliorate their functional impairment， and the above effects are associated with the inhibition of the AGE/RAGE signaling pathway.

Liraglutide protects nucleus pulposus cells by inhibiting the activation of NLRP3 inflammasome in high glucose environment / 中国糖尿病杂志

Objective To evaluate the protective effect of human nucleus pulposus cell by Liraglutide(Lir)under high-glucose environment via inhibition of NOD-like receptor family,pyrin domain containing 3(NLRP3)inflammasome activation and its mechanism.Methods Human nucleus pulposus cell lines were cultured and the third-generation nucleus pulposus cells were randomly divided into control group(Con group),high glucose group(HG group),and Liraglutide interference group(Lir group),and cultured for 48 h.ELISA was used to detect interleukin IL-1β;flow cytometry was used to testreactive oxygen species(ROS),and Western blot was used to evaluate the protein expressions of NLRP3,Pro-caspase-1,and Caspase-1.Results Compared with Con group,IL-1β,ROS,NLRP3,Pro-caspase-1,Caspase-1 protein expression and cell apoptosis were increased in HG and Lir groups(P<0.05).Compared with HG group,IL-1β,ROS,NLRP3,Pro-caspase-1,Caspase-1 protein expression and cell apoptosis were significantly decreased in Lir group(P<0.05).Conclusion Liraglutide protects human NPCs by inhibiting the activation of NLRP3 inflammasome,reducing IL-1β secretion,and inhibiting cell apoptosis.

Rubescensine A reduces podocyte damage induced by high glucose through the autophagy pathway mediated by AMPK/SIRT1 pathway / 中国糖尿病杂志

Objective To investigate the mechanism that Rubescensine A reduces the podocyte damage induced by high glucose(HG)through the autophagy pathway mediated by AMP activated protein kinase/silent information regulator 1(AMPK/SIRT1)pathway.Methods Human glomerular podocytes were cultured in vitro,and randomly divided into Control group(Con),HG group,hydroxychloroquine(HCQ)group,and Rapamycin(RAP)group.CCK-8 was used to detect cell viability.Western blotting was used to detect cell apoptosis and podocyte injury related protein expression in each group.The podocyte model induced by high glucose(HG)was treated with Rubescensine A(Rub A)at different concentrations and the optimal concentration was selected.Then,human glomerular podocytes were randomly divided into Con group,HG group,Rub A group,Compound C group,and Rub A+Compound C group.The expression of autophagy,AMPK/SIRT1 pathway related proteins were detected in each group.Results Compared with Con group,the podocyte viability and the protein expressions of Synaptopodin and Bcl-2 was significantly reduced(P<0.05),while the protein expressions of Desmin and Bax were significantly increased in HG group(P<0.05).Compared with the HG group,all indicators were relieved in RAP group.However,the levels of all indicators were worsened in HCQ group.Compared with Con group,the expression levels of Desminand Bax proteins in podocytes were significantly increased(P<0.05),and the podocyte viability,number of autophagosomes,the expression levels of Synaptopodin,Bcl-2,microtubule associated protein light chain 3(LC3)II/I,Beclin-1,p-AMPK/AMPK and SIRT1 proteins were significantly reduced in HG group(P<0.05).Compared with HG group and Rub A+Compound C group,the above indicators were improved in Rub A group.Compound C group reversed the protective effect of Rub A.Conclusion Rubescensine A can promote autophagy by activating AMPK/SIRT1 pathway,thereby reduce podocyte damage induced by high glucose.

Effect of circLRP6 on high glucose-induced renal tubular epithelial cell injury via miR-31-5p/HMGA1 axis regulation / 中国医科大学学报

Objective To analyze the effect of circLRP6 on high glucose-induced renal tubular epithelial cell injury via miR-31-5p/high mobility group protein A1(HMGA1)axis regulation.Methods Human renal tubular epithelial HK-2 cells were cultured in vitro and divided into eight groups:control,high glucose,high glucose+si-NC,high glucose+si-circLRP6,high glucose+si-circLRP6+miR-NC,high glucose+si-circLRP6+miR-31-5p inhibitor,high glucose+si-circLRP6+miR-31-5p inhibitor+si-NC,and high glucose+si-circ-LRP6+ miR-31-5p inhibitor+si-HMGA1.The circLRP6,miR-31-5p,and HMGA1 mRNA levels were determined using real-time quantitative PCR.Cell supernatant IL-6 and tumor necrosis factor-α(TNF-α)levels,lactate dehydrogenase(LDH)activity,and malondialdehyde(MDA)content were also determined.Furthermore,flow cytometry was used to observe cell apoptosis.HMGA1,Bax,and Bcl-2 protein expression was detected by Western blotting.Finally,dual luciferase assay was used to report the targeting relationship of miR-31-5p with circLRP6 and HMGA1.Results Compared with the high glucose group,the HK-2 cell proliferation inhibition rate;cell superserum IL-6,TNF-α,LDH,and MDA levels;apoptosis rate;and Bax protein expression in the high glucose+si-circLRP6 group decreased significantly,whereas Bcl-2 protein expression increased significantly(all P＜0.05).Consequently,miR-31-5p downregulation possibly weakened the protective effect of si-circLRP6 on high glucose-induced renal tubular epithelial cell injury.HMGA1 expression inhibition reversed the effect of the si-circLRP6+miR-31-5p inhibitor on high glucose-induced renal tubular epithelial cell injury.Finally,miR-31-5p exhibited a targeting relationship with circLRP6 and HMGA1.Conclusion Si-circLRP6 protects high glucose-induced renal tubular epithelial cell injury via miR-31-5p upregulation and HMGA1 expression inhibition.

miR-519d-3p alleviates high glucose-induced human retinal microvascular endothelial cells dysfunction and inhibits angiogenesis by targeting hypoxia inducible factor 1 subunit alpha / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To clarify the effect of miR-519d-3p on high glucose-induced human retinal microvascular endothelial cells(HRMEC)dysfunction and angiogenesis, and to elucidate the regulatory mechanism of miR-519d-3p on hypoxia inducible factor 1 subunit alpha(HIF-1α).METHODS: The normal glucose(NG)and high glucose(HG)cell models were established by inducing HRMEC with 5 and 30 mmol/L glucose, respectively. Control group: HG cell model was transfected with negative control mimics; mannitol group: the control group was added with 25 mmol/L mannitol; miR-519d-3p overexpression group: HG cell model was transfected with miR-519d-3p mimics; miR-519d-3p combined with HIF-1α overexpression group: HG cell model was co-transfected with miR-519d-3p mimics and HIF-1α overexpression vector. The expression of miR-519d-3p in each group was tested by real-time fluorescence quantitative PCR. The expression of HIF-1α protein in each group was tested by Western blotting. The binding sites between miR-519d-3p and HIF-1α were detected by luciferase reporter gene assay. The cell proliferation of each group was detected by CCK-8. The cell apoptosis of each group was tested by Hoechst 33342 staining. The protein expression of extracellular fluid inflammatory factors tumor necrosis factor-α(TNF-α), interleukin(IL)-1β and IL-6 in each group was tested by ELISA. The formation of new capillary lumen-like structures was detected by tubule formation assay.RESULTS: Compared with the NG, miR-519d-3p expression was significantly reduced in the HG cell model, while HIF-1α protein expression was significantly increased in the HG(all P&#x003C;0.01). Compared with the control group, HIF-1α protein expression was significantly reduced in the miR-519d-3p overexpression group(P&#x003C;0.01). The “CGUGAAA” sequence of miR-519d-3p could specifically bind to the “GCACUUU” sequence of HIF-1α 3'-untranslated region(3'-UTR). Compared with the control group, the miR-519d-3p overexpression group showed a significant increase in 24, 48 and 72h absorbance values, a significant decrease in cell apoptotic rate, a significant decrease in the concentrations of TNF-α, IL-1β and IL-6, and a significant decrease in the number of new capillary lumen-like structures(all P&#x003C;0.01). Compared with the miR-519d-3p overexpression group, the miR-519d-3p combined with HIF-1α overexpression group showed a significant decrease in 24, 48 and 72h absorbance values, a significant increase in cell apoptotic rate, a significant increase in the concentrations of TNF-α, IL-1β and IL-6, and a significant increase in the number of new capillary lumen-like structures(all P&#x003C;0.01). There was no difference between the control group and mannitol group in the comparison of the above indicators(all P&#x003E;0.05).CONCLUSION: miR-519d-3p expression is down-regulated while HIF-1α protein expression is up-regulated in high glucose induced HRMEC model. HIF-1α is a target gene of miR-519d-3p. The miR-519d-3p targets HIF-1α to increase cell proliferation and reduce cell apoptosis and inflammation, thereby alleviating high glucose-induced HRMEC dysfunction and inhibiting angiogenesis.

Terpinen-4-ol inhibits proliferation of VSMCs exposed to high glucose via regulating KLF4/NF-κB signaling pathway / 中国中药杂志

This study aimed to observe the effect of terpinen-4-ol(T4O) on the proliferation of vascular smooth muscle cells(VSMCs) exposed to high glucose(HG) and reveal the mechanism via the Krüppel-like factor 4(KLF4)/nuclear factor kappaB(NF-κB) signaling pathway. The VSMCs were first incubated with T4O for 2 h and then cultured with HG for 48 h to establish the model of inflammatory injury. The proliferation, cell cycle, and migration rate of VSMCs were examined by MTT method, flow cytometry, and wound healing assay, respectively. The content of inflammatory cytokines including interleukin(IL)-6 and tumor necrosis factor-alpha(TNF-α) in the supernatant of VSMCs was measured by enzyme-linked immunosorbent assay(ELISA). Western blot was employed to determine the protein levels of proliferating cell nuclear antigen(PCNA), Cyclin D1, KLF4, NF-κB p-p65/NF-κB p65, IL-1β, and IL-18. The KLF4 expression in VSMCs was silenced by the siRNA technology, and then the effects of T4O on the cell cycle and protein expression of the HG-induced VSMCs were observed. The results showed that different doses of T4O inhibited the HG-induced proliferation and migration of VSMCs, increased the percentage of cells in G_1 phase, and decreased the percentage of cells in S phase, and down-regulated the protein levels of PCNA and Cyclin D1. In addition, T4O reduced the HG-induced secretion and release of the inflammatory cytokines IL-6 and TNF-α and down-regulated the expression of KLF4, NF-κB p-p65/NF-κB p65, IL-1β, and IL-18. Compared with si-NC+HG, siKLF4+HG increased the percentage of cells in G_1 phase, decreased the percentage of cells in S phase, down-regulated the expression of PCNA, Cyclin D1, and KLF4, and inhibited the activation of NF-κB signaling pathway. Notably, the combination of silencing KLF4 with T4O treatment further promoted the changes in the above indicators. The results indicate that T4O may inhibit the HG-induced proliferation and migration of VSMCs by down-regulating the level of KLF4 and inhibiting the activation of NF-κB signaling pathway.

Teriparatide regulates osteoblast differentiation in high-glucose microenvironment through the cAMP/PKA/CREB signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effect of teriparatide on the differentiation of MC3T3-E1 cells in high-glucose microenvironment and explore the possible mechanism.@*METHODS@#MC3T3-E1 cells cultured in normal glucose or high-glucose (25 mmol/L) medium were treated with 10 nmol/L teriparatide with or without co-treatment with H-89 (a PKA inhibitor). CCK-8 assay was used to detect the changes in cell proliferation, and cAMP content in the cells was determined with ELISA. Alkaline phosphatase (ALP) activity and mineralized nodules in the cells were detected using ALP kit and Alizarin red staining, respectively. The changes in cell morphology were detected by cytoskeleton staining. Real-time PCR was used to detect the mRNA expressions of PKA, CREB, RUNX2 and Osx in the treated cells.@*RESULTS@#The treatments did not result in significant changes in proliferation of MC3T3-E1 cells (P > 0.05). Compared with the cells in routine culture, the cells treated with teriparatide showed significantly increased cAMP levels (P < 0.05) with enhanced ALP activity and increased area of mineralized nodules (P < 0.05). Teriparatide treatment also resulted in more distinct visualization of the cytoskeleton in the cells and obviously up-regulated the mRNA expressions of PKA, CREB, RUNX2 and Osx (P < 0.05). The opposite changes were observed in cells cultured in high glucose. In cells exposed to high glucose, treatment with teriparatide significantly increased cAMP levels (P < 0.05), ALP activity and the area of mineralized nodules (P < 0.05) and enhanced the clarity of the cytoskeleton and mRNA expressions of PKA, CREB, RUNX2 and Osx; the effects of teriparatide was strongly antagonized by co-treatment with H-89 (P < 0.05).@*CONCLUSION@#Teriparatide can promote osteoblast differentiation of MC3T3-E1 cells in high-glucose microenvironment possibly by activating the cAMP/PKA/CREB signaling pathway.

Role of ROS/TXNIP/NLRP3 signaling pathway in high glucose-induced pyroptosis of human embryonic trophoblast cells / 中华内分泌外科杂志

Objective:To investigate the changes of ROS/TXNIP/NLRP3 signaling pathway in pyroptosis of human embryonic trophoblast cells induced by high glucose.Methods:Human embryonic trophoblast cells were cultured in vitro to establish high glucose injury model, and they were randomly divided into control group, high glucose (HG) group and HG + ROS inhibitor N-acetyl-L-cysteine (HG + NAC) group. MTT assay was used to detect the cell survival rate. The level of ROS in each group was detected by dihydroethidine ROS fluorescence probe. Expression of TXNIP and NLRP3 mRNA was detected by real-time quantitative PCR (RT-qPCR). Western blot analysis was used to detect the expression levels of TXNIP, NLRP3, Caspase-1, interleukin (IL) -1β, tumor necrosis factor-α (TNF-α) and GSDMD proteins. In addition, pyroptosis was detected by flow cytometry.Results:The optimal glucose concentration for high glucose-induced injury of human embryonic trophoblast cells was 30 mmol/L. Compared with the control group (96.27±3.10) %, the survival rate of human embryonic trophoblast cells in HG group (55.44±2.15) % was significantly lower ( P<0.05), while the fluorescence intensity (ROS level) of 7 'dichlorofluorescein (DCF), the expression levels of TXNIP and NLRP3 proteins, the number of pyroptosis, expression levels of Caspase-1, GSDMD, IL-1β and TNF-α proteins were significantly higher ( P<0.05) ; Compared with HG group, the survival rate of human embryonic trophoblast cells in HG+NAC group (84.75±2.33) % was significantly higher ( P<0.05), the fluorescence intensity (ROS level) of DCF, the expression levels of TXNIP and NLRP3 proteins, the number of pyroptosis, and expression levels of Caspase-1, GSDMD, IL-1β and TNF-α proteins were significantly lower ( P<0.05) . Conclusion:Inhibition of ROS level in human embryonic trophoblast cells induced by high glucose may promote cell proliferation and reduce the occurrence of pyroptosis by inhibiting TXNIP/NLRP3 signaling pathway.

Antagonistic effect of SC79 on high glucose-induced apoptosis of RPE cells and its regulatory mechanism on AKT-XIAP signaling pathway / 中华实验眼科杂志

Objective:To investigate the antagonistic effect and potential mechanism of specific AKT activator SC79 on the apoptosis of human retinal pigment epithelial (ARPE)-19 cells induced by high glucose in vitro. Methods:The ARPE-19 cells were cultured in high glucose medium (containing 30 mmol/L glucose) plus 5, 10 or 20 μg/ml SC79, respectively.After 6-, 12- and 24-hour culture, the optimal experimental concentration and timing were determined according to cell proliferation rate.Then ARPE-19 cells were divided into four groups, normal control group cultured in normal medium containing 5.6 mmol/L glucose for 48 hours, mannitol group cultured in medium containing 5.6 mmol/L glucose and 24.4 mmol/L mannitol for 48 hours, high glucose group cultured in high glucose medium for 48 hours, and high glucose+ SC79 group cultured in normal medium containing 10 μg/ml SC79 for 12 hours plus in high glucose medium for 36 hours.The proliferation rate of APRE-19 cells was detected by MTS assay.The apoptosis rate was measured by flow cytometry.The relative expression levels of phosphorylated protein kinase B (p-Akt), X-linked inhibitor of apoptosis protein (XIAP), caspase-9, caspase-3 and its active fragments (active-caspase-3) were assayed by Western blot.The ARPE-19 cells were divided into Neg-shRNA group, AKT shRNA group and blank control group and were treated with the corresponding transfection complex and serum-free medium.The AKT mRNA expression was detected by real-time PCR.The transfected ARPE-19 cells were divided into Neg-shRNA+ SC79 group and AKT shRNA+ SC79 group and were cultured according to the culturing method of high-glucose+ SC79 group.The apoptosis rate of the two groups was tested by flow cytometry.Results:Among different concentrations of SC79 and treatment times, the proliferation rate of cells treated with 10 μg/ml SC79 for 12 hours was the highest.The proliferation rate of ARPE-19 cells in high-glucose group was significantly lower than that in normal control group, mannitol group and high-glucose+ SC79 group, and the differences were statistically significant (all at P<0.01). The apoptosis rate of cells in the high-glucose group was (52.27±3.21)%, which was significantly higher than (3.90±0.71)% in normal control group and (20.70±3.62)% in high-glucose+ SC79 group (both at P<0.01). The relative expression levels of p-Akt, XIAP, caspase-9 and caspase-3 were significantly lower and the relative expression level of active-caspase-3 was significantly higher in high glucose group than those in normal control group and high-glucose+ SC79 group (all at P<0.05). The relative expression level of AKT mRNA in normal control group, Neg-shRNA group and AKT shRNA group was 0.60±0.07, 0.59±0.03 and 0.11±0.10, respectively, showing a statistically significant difference among the groups ( F=30.44, P<0.01). The apoptosis rate of cells in the AKT shRNA+ SC79 group was significantly higher than that in high-glucose+ SC79 group and Neg-shRNA+ SC79 group (both at P<0.001). Conclusions:SC79 can partially antagonize the apoptosis of ARPE-19 cells induced by high glucose, which is related to the activation of AKT/XIAP pathway and the inhibition of the caspase family.

Effect of high glucose on intracellular cholesterol content in rat glomerular mesangial cells / 中国医师杂志

Objective:To investigate the effect of high glucose on intracellular cholesterol content in rat glomerular mesangial cells and the underlying mechanism.Methods:Rat glomerular mesangial cells were cultured in vitro and divided into high glucose culture group (high glucose group, medium glucose concentration of 30 mmol/L) and normal glucose culture group (normal group, medium glucose concentration of 5.5 mmol/L). Lipid content was determined by oil red O staining and spectrophotometer colorimetry at 24, 36 and 48 h of culture. Intracellular protein imprinting was used to detect the expression of low density lipoprotein cholesterol receptor (LDLR) and adenosine triphosphate binding cassette A1 (ABCA1). Results:Oil red O staining showed that the intracellular lipid drops in the high glucose group were less than those in the normal group at 36 h, and there was no significant difference between the two groups at 24 h and 48 h of culture. The total cholesterol (TC) and cholesterol ester (CE) in glomerular mesangial cells of rats in the high glucose group were significantly lower than those in the normal group ( P=0.028, 0.029), while there was no significant difference in the free cholesterol (FC) between the two groups ( P=0.306). There was no significant difference in TC, CE and FC between the two groups at 24 and 48 h of culture (all P>0.05). The expression of LDLR in mesangial cells of rats in high glucose group was significantly lower than that in normal group at 24, 36 and 48 h of culture ( P=0.043, 0.004, 0.028), and the expression of ABCA1 was significantly higher than that in normal group at 24, 36 and 48 h of culture, ( P=0.050, 0.009, 0.006). Conclusions:High glucose may reduce intracellular cholesterol content in rat glomerular mesangial cells by reducing LDLR protein expression and increasing ABCA1 protein expression.

To investigate the effect of Astragaloside Ⅳ on high-glucose-induced cardiomyocytes pyroptosis / 中华老年医学杂志

Objective:To investigate the effect of Astragaloside Ⅳ on high glucose-induced cardiomyocyte pyroptosis.Methods:H9c2 cells were cultured in vitro and divided into control group(5.5 mmol/L glucose), high glucose group(33.3 mmol/L glucose), Astragaloside Ⅳ group(33.3 mmol/L glucose+ 100μmol/L Astragaloside Ⅳ), and NLRP3 inhibitor group(33.3 mmol/L glucose+ 1μmol/L MCC950). Cell counting kit 8(CCK-8)was used to detect the activity of H9c2 cells.Lactate dehydrogenase(LDH)kit was used to detect the content of LDH in cell supernatant.Superoxide anion fluorescent probe(DHE)was used to detect the level of intracellular reactive oxygen species(ROS). Real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)and Western blot were used to detect the mRNA and protein expression levels of pyroptosis-related genes.Immunofluorescence was used to detect the fluorescence intensity of NLRP3.Enzyme-linked immunosorbent assay(ELISA)was used to detect the level of inflammatory factors in cell supernatant.Results:When the concentration of Astragaloside Ⅳ was 100 μmol/L, it could significantly inhibit the decrease of cardiomyocyte viability induced by high glucose( P<0.01)and reduce LDH release( P<0.01). Compared with the control group, the level of ROS was increased( P<0.01), the mRNA and protein expressions of pyroptosis-related molecules were up-regulated( P<0.01 for all), the fluorescence intensity of NLRP3 was increased( P<0.01), and the levels of inflammatory factors in the cell supernatant were increased in the high glucose group( P<0.01). Compared with the high glucose group, the ROS level was decreased( P<0.01), the mRNA and protein expressions of pyroptosis-related molecules were down-regulated( P<0.05 or P<0.01), the fluorescence intensity of NLRP3 was decreased( P<0.01), and the levels of inflammatory factors in cell supernatant were decreased( P<0.05 or P<0.01)in Astragaloside Ⅳ group and inhibitor group. Conclusions:Astragaloside Ⅳ plays a protective role in high glucose-induced cardiomyocyte injury by inhibiting NLRP3/Caspase-1 signaling pathway and inhibiting pyroptosis.Moreover, it can improve the anti-inflammatory and antioxidant properties in cell models.

Liraglutide ameliorates high glucose-induced oxidative stress injury in rat H9c2 cells through modulation of SIRT1 / 中华内分泌代谢杂志

Objective:To investigate the effect of liraglutide(LRG) on high glucose-induced oxidative stress injury in(H9c2) cardiomyocytes and its underlying mechanisms.Methods:A high glucose treatment was applied to H9c2 cells for 24 hours to establish an in vitro model of myocardial cell injury. Different concentrations of liraglutide(10, 100, 1000 nmol/L) were administered for intervention. Cell viability was evaluated using the CCK-8 assay, and changes in cell morphology were observed under an inverted microscope. After 24 hours of liraglutide(100 nmol/L) intervention following high glucose treatment, the levels of lactate dehydrogenase(LDH), superoxide dismutase(SOD), and malondialdehyde(MDA) in the cell supernatant were measured. RT-PCR and Western blotting were used to detect the mRNA and protein levels of silent information regulator factor 1(SIRT1) and forkhead box protein O1(FOXO1). Western blotting was also used to assess the acetylation level of FOXO1 protein. Small interfering RNA(siRNA) technology was employed to silence SIRT1 in H9c2 cells to confirm its role in the study. Results:Compared to the control group, the high glucose group showed decreased cell viability, cell structure damage, increased levels of LDH and MDA in the cell supernatant, decreased SOD levels, aggravated oxidative stress, decreased SIRT1 expression, and increased acetylation level of FOXO1(all P<0.05). Compared to the high glucose group, liraglutide intervention resulted in increased cell viability, improved cardiac cell morphology, reduced oxidative stress levels, increased SIRT1 expression, and decreased acetylation level of FOXO1(all P<0.05). When SIRT1 was downregulated, the protective effects of liraglutide were weakened(all P<0.05). Conclusions:Liraglutide has a protective effect against high glucose-induced oxidative stress injury in H9c2 cells, which may be associated with the upregulation of SIRT1 expression.

Effects of miR-34a on polarization and inflammatory factor content of mouse macrophage cell line RAW264.7 under high glucose conditions / 基础医学与临床

Objective To detect the role of miR-34a on macrophage inflammation and polarization under high glucose conditions.Methods Mouse macrophages were collected and cultured during high glucose for 3－28 days.RT-qPCR was used to detect the expression of miR-34a,iNOS,MCP-1 and Arg-1 mRNA.Then miR-34a was over-expressed or silenced,ELISA was used to detect the expression of IL-6,IL-1β,TNF-α and qRT-PCR was used to detect the expression of iNOS and MCP-1 mRNA.Western blot was used to detect the expres-sion of Notch1.Results Expression of miR-34a increased under high glucose conditions in RAW264.7 cells continuously.Over-expression of miR-34a promoted the expression of MCP-1 and iNOS observed by RT-qPCR and increased the expression of IL-6,IL-1β and TNF-α detected by ELISA.Further studies showed that siRNA-Notch1 down-regulated the expression of miR-34a,MCP-1,iNOS,IL-6,IL-1β and TNF-α.Conclusions Chronic high glucose condition stimulates the expression of miR-34a which promotes M1 macrophage polarization and releasing of pro-inflammatory factors.

Impact of LncRNA TUG1 on high glucose-induced cardiomyocyte apoptosis by regulating the miR-181b-5p/PDCD4 axis / 天津医药

Objective To investigate the impact of long non-coding RNA(LncRNA)taurine up-regulated gene 1(TUG1)on high glucose-induced cardiomyocyte apoptosis by regulating miR-181b-5p/programmed cell death protein 4(PDCD4)axis.Methods Diabetic cardiomyopathy(DCM)cell model was established in vitro with high glucose(HG,25 mmol/L glucose).AC16 cells were divided into the NG(5.5 mmol/L glucose)group,the HG group,the HG+sh-NC group,the HG+sh-TUG1 group,the HG+miR-NC group,the HG+miR-181b-5p group,the HG+sh-TUG1+anti-miR-NC group,the HG+sh-TUG1+anti-miR-181b-5p group,the HG+miR-181b-5p+pcDNA group and HG+miR-181b-5p+pc-PDCD4 group.The Cell Counting Kit-8(CCK-8)method was applied to detect cell viability.Lactate dehydrogenase(LDH)assay was applied to detect LDH release.Quantitative real-time polymerase chain reaction(qRT-PCR)was applied to detect expression levels of TUG1,miR-181b-5p and PDCD4 mRNA.Flow cytometry was applied to detect apoptosis.Western blot assay was applied to detect levels of B-cell lymphoma 2-associated X(Bax),activated caspase 3(cleaved caspase 3)and PDCD4 proteins.Caspase-Glo3 assay was applied to assess caspase 3 activity.Dual-luciferase reporter assay was applied to verify the targeting relationship between TUG1 or PDCD4 and miR-181b-5p.Results Compared with the NG group,the cell activity decreased in the HG group,and LDH release,apoptosis rate,Bax,cleaved caspase 3 expression and caspase 3 activity increased(P＜0.05),which could be antagonized by TUG1 knockdown or miR-181b-5p overexpression(P＜0.05).Inhibition of miR-181b-5p was able to alleviate the impact of TUG1 silencing on cardiomyocyte viability and apoptosis under high glucose treatment(P＜0.05).The overexpression of PDCD4 attenuated the promotion effect of miR-181b-5p up-regulation on the viability of cardiomyocytes treated with high glucose and the inhibitory effect on apoptosis.TUG1 was able to increase the expression of PDCD4 through adsorption of miR-181b-5p(P＜0.05).Conclusion TUG1 promotes high glucose-induced cardiomyocyte apoptosis by down-regulating miR-181b-5p and up-regulating PDCD4.