Impacts of andrographolide on sciatic nerve function damage in diabetic peripheral neuropathy rats by regulating HMGB1/RAGE signaling pathway / 中国药房

OBJECTIVE To investigate the impacts of andrographolide on sciatic nerve function injury in diabetic peripheral neuropathy （DPN） rats by regulating high-mobility group protein box 1 （HMGB1）/receptor for advanced glycation end products （RAGE） signal pathway. METHODS A total of 84 rats were randomly divided into the control group （normal saline）， DPN group （normal saline）， low-dose andrographolide group （0.833 mg/kg）， high-dose andrographolide group （3.332 mg/kg）， lipoic acid group （positive control， 0.1 g/kg）， recombinant rat HMGB1 protein （rHMGB1） group （8 μg/kg）， and high-dose andrographolide+ rHMGB1 group， with 12 rats in each group. All rats except those in the control group were fed with high glucose and high fat diet combined with intraperitoneal injections of streptozotocin to establish the DPN rat model. After 24 hours of successful modeling， medication was administered daily for 8 weeks. The changes in fasting blood glucose， mechanical pain threshold， heat pain threshold and sciatic nerve conduction velocity were detected. Pathological changes in the sciatic nerve of rats and the activity of superoxide dismutase （SOD） and the content of malondialdehyde （MDA） in the sciatic nerve of rats were also detected. Besides， the expressions of HMGB1， RAGE proteins and phosphorylation level of nuclear factor κB p65（NF-κB p65） protein in rat sciatic nerves were found. RESULTS Compared with the control group， the pathological damage of the sciatic nerve of rats in the DPN group was strengthened， the fasting blood glucose， heat pain threshold， MDA content and the 诊治。E-mail：dqiaur@163.com expressions of HMGB1， RAGE proteins and phosphorylation level of NF-κB p65 protein were increased （P＜0.05）， while the mechanical pain threshold， sensory nerve conduction velocity， motor nerve conduction velocity， and SOD activity were decreased/slowed down （P＜0.05）. Compared with the DPN group， the above indexes were significantly potentiated in the andrographolide low- and high-dose groups and lipoic acid group （P＜0.05）， and the corresponding trends in the rHMGB1 group were opposite to those in the above three administration groups （P＜0.05）. Moreover， rHMGB1 attenuated the hypoglycemic effect of high-dose andrographolide on blood glucose and the improvement of oxidative stress injury in the sciatic nerve of DPN rats （P＜0.05）. CONCLUSIONS Andrographolide may reduce blood glucose by inhibiting the HMGB1/RAGE pathway and oxidative stress， thus ameliorating sciatic nerve injury in DPN rats.

MiR-340 mediates the involvement of high mobility group box 1 in the pathogenesis of liver fibrosis / 中华肝脏病杂志

Objective: To explore the pathogenic mechanism of the miR-340/high mobility group box 1 (HMGB1) axis in the formation of liver fibrosis. Methods: A rat liver fibrosis model was established by injecting CCl(4) intraperitoneally. miRNAs targeting and validating HMGB1 were selected with gene microarrays after screening the differentially expressed miRNAs in rats with normal and hepatic fibrosis. The effect of miRNA expressional changes on HMGB1 levels was detected by qPCR. Dual luciferase gene reporter assays (LUC) was used to verify the targeting relationship between miR-340 and HMGB1. The proliferative activity of the hepatic stellate cell line HSC-T6 was detected by thiazolyl blue tetrazolium bromide (MTT) assay after co-transfection of miRNA mimics and HMGB1 overexpression vector, and the expression of extracellular matrix (ECM) proteins type I collagen and α-smooth muscle actin (SMA) was detected by western blot. Statistical analysis was performed by analysis of variance and the LSD-t test. Results: Hematoxylin-eosin and Masson staining results showed that the rat model of liver fibrosis was successfully established. Gene microarray analysis and bioinformatics prediction had detected eight miRNAs possibly targeting HMGB1, and animal model validation had detected miR-340. qPCR detection results showed that miR-340 had inhibited the expression of HMGB1, and a luciferase complementation assay suggested that miR-340 had targeted HMGB1. Functional experiments results showed that HMGB1 overexpression had enhanced cell proliferation activity and the expression of type I collagen and α-SMA, while miR-340 mimics had not only inhibited cell proliferation activity and the expression of HMGB1, type I collagen, and α-SMA, but also partially reversed the promoting effect of HMGB1 on cell proliferation and ECM synthesis. Conclusion: miR-340 targets HMGB1 to inhibit the proliferation and ECM deposition in hepatic stellate cells and plays a protective role during the process of liver fibrosis.

Research progress of intracellular high mobility group box B1 / 中国小儿急救医学

High mobility group box 1 ( HMGB1 ) is a highly conserved DNA-binding protein. The function of HMGB1 varied according to its molecular localization. Meanwhile,HMGB1 is located in the nu-cleus under physiological conditions. It contains stable nucleosome structure and can promote gene recombina-tion,repair,transcription etc,known as the"DNA chaperone". Intracellular HMGB1 has a protective effect on heart hypertrophy, heart failure, pancreatitis, hepatic ischemia/reperfusion injury, spinocerebellar ataxia and other protective effects.

Clinical research progress on high mobility group protein box 1 / 中国小儿急救医学

High mobility group protein box 1 (HMGB1) is a highly conserved DNA binding protein, which is found in the nucleus of a variety of cells in the body, regulating the transcription of cell genes.It plays a role of nuclear binding protein in physiological state.Once released into the cell gap, it performances the role of inflammatory mediators.Recent studies showed that pathogenesis of HMGB1 not only involved in sepsis, autoimmune diseases, chronic liver disease, malignant tumor, but also involved in cell injury repair,which plays important role in a variety of diseases, organ damage, repair process.

Changes and significance of serum tumor markers in patients with esophageal squamous cell carcinoma re-section / 实用医学杂志

Objective To explore the dynamic changes of serum HMGB1, CEA and SCC as well as the value in the evaluation of prognosis of patients with esophageal squamous cell carcinoma resection. Methods The dynamic changes in serum levels of HMGB1, CEA and SCC were measured respectively in 100 patients preopera-tively as well as a month after esophagectomy. The relationships between the changes of serum tumor markers and the clinical efficacy were analyzed. Results The 5-years survival rate of the CEA, SCC and HMGB1 negative peo-ple before operation was significantly higher than that of the positive patients (P < 0.05). The 5-years survival rate of those patients with all three markers negative before operation was significantly higher than that of those patients with the three markers positive (P < 0.01). The Median Survive Time of the patients with the levels of all three markers decreased after operation was longer than those with the levels of all the three markers increased (χ2 =6.584, P=0.01). The Median Survive Time of the patients with levels of the three markers decreased by more than 50%was longer than those with the levels decreased by less than 50% (χ2=5.418, P = 0.02). Conclusions The dynamic and combined detections of serum HMGB1, CEA, SCC in patients with esophageal squamous cell carcino-ma resection can effectively evaluate the therapeutic effect and prognosis.

Relationship and mechanism between the serum level of HMGB1 and the mortality rate in patients with sepsis / 中国基层医药

Objective To investigate the relationship and mechanism between the serum level of high mobility group box protein-1(HMGB1)and the mortality rate in patients with sepsis.Methods The serum levels of HMGB1,superoxide dismutase(SOD)and malondialdehyde(MDA)in 48 patients with sepsis were determined.The clinical outcomes in those patients were recorded and anlyzed.Results After the onset of sepsis,the serum HMGB1 levels of both death group and survival group were increased gradually and peaked at 72h after the onset of the disease.The semm HMGB1 levels of death group were much higher than those of survival group except at 24h(t=6.07,6.20,24.43,all P＜0.05).The activity of serum SOD of death group was markedly lower than that of survival group at 12h,24h,48h and 72h(t=10.24,20.61,11.67,33.33,all P＜0.05),and the level of serum MDA of death group was significantly higher than those of survival group at all time points(t=26.06,22.17,23.86,9.49,5.95,all P＜0.05).There was a significantly positive correlation between the serum HMGB1 and MDA level.Conlusioa The increase in serum HMGB1 level may be the important reasoll for the increased mortality rate in patients with sepsis;Oxidant/antioxidant imbalance may be olle reason for the increase in serum HMGB1 level.

The effect of HMGB1 on the renal injure of systemic lupus erythematosus mediated in part via the TLR4 pathway / 中华微生物学和免疫学杂志

Objective To investigate the relationship between the effect of high mobility group protein box 1 (HMGBI) on the renal injure of systemic lupus erythematosus (SLE) and the expression of Toll-like receptor 4(TLR4). Methods The level of HMGB1, MMP-2 and TIMP-2 in serum from 16 pa-tients with SLE, 18 patients with lupus nephritis(LN) and 12 healthy people were measured by ELISA. The fresh peripheral blood mononuelear cell (PBMC) were isolated and the total RNA was extracted. Then the mRNA expression of HMGB1 was amplified by RT-PCR. Flow cytometry analysis was performed to study cell surface markers and the expression of TLR4. Results RT-PCR and ELISA results showed that the expres-sions of mRNA and level of HMGB1 protein in serum were higher in patients with LN than those in SLE and healthy people. The expression of TLR4 in CD14+ monecytes of patients with LN was higher than that with SLE and healthy people, while there were no significance in CD3+ T cells among LN, SLE and healthy peo-ple. The expressions of MMP-2 and TIMP-2 in serum of LN was lower than that in SLE and healthy people, at the same time the ratio of MMP-2/TIMP-2 decreased in LN group. HMGB1 mRNA and CD14+/TLR4+ was negatively correlated with the ratio of MMP-2/TIMP-2, and the level of HMGB1 in serum was positively correlated with proteinuria, while negatively correlated with the ratio of MMP-2/TIMP-2 in LN. Conclusion HMGB1 is one of the important cytokine in the pathogenesis of lupus nephritis. HMGBI might play a role in proteinuria of lupus nephritis in part via TLR4 pathway to activate monocytes and decrease the expression of MMP-2/TIMP-2.

Effects of TLR/STAT pathway on the proliferation of mesangial cell induced by HMGB1 / 中国免疫学杂志

Objective:To investigate the effects of TLR/STAT pathway in the proliferation of mesangial cell induced by HMGB1.Methods:Human mesangial cells were inoculated in the dose of 1?104 ml-1.After 24 h,cells were cultured with standard medium as control group or with medium supplement with 10 ?g/L human recombinant protein HMGB1 as trial group in vitro.Then the cells were collected in 6,12 and 24 h respectively,as well as control group cells.Immunocytochemical staining was adopted to examine the expressions of PCNA proteins on mesangial cells in different groups.Immunocytochemical staining and FCM were performed to detect the changes of TLR2 protein expression.STAT1 and STAT3 mRNA were examined by RT-PCR technique.Results:Immunocytochemical staining indicated that the mesangial cells could multiply after they were induced by human recombinant protein HMGB1.Immunocytochemical staining showed that the level of TLR2 protein in trial groups were higher than those in control groups.FCM indicated that HMGB1 could significantly up-regulate the expression of TLR2 protein time-dependently.The STAT1 and STAT3 mRNA in HMGB1 groups were higher than those in control groups.The expression of TLR2 protein was positively correlated with those of STAT1 and STAT mRNA respectively.The positive rate of PCNA was remarkably correlated with the expression of STAT1 and STAT3 mRNA.Conclusion:HMGB1 could activate STAT1/STAT3 through combining with its cell-surface receptor TLR2,which may play an important role in promoting the proliferation of mesangial cells and then damaging the renal of lupus nephritis.