1.The effects and mechanisms of benazepril and losartan on glomerular podocyte autophagy in aged spontaneously hypertensive rats
Mingjiao PAN ; Mengyun XIAO ; Yang LYU ; Bo FU ; Lu YU ; Xiaodan WANG
Chinese Journal of Geriatrics 2016;35(8):888-893
Objective To examine the effects of benazepril and losartan on glomerular podocyte autophagy in aged spontaneously hypertensive rats (SHRs) and investigate the underlying mechanisms of renal-protective effects of angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor blockers (ARB).Methods Wistar-Kyoto rats (WKYs) were used as the normal control (NORM) group (2 ml physiological saline per day).SHRs were randomly divided into 4 groups:the CTRL group (2 ml physiological saline per day),the ACEI group (10 mg · kg-1 · d-1),the ARB group (30 mg· kg-1 ·d-1) and the combined group (10 mg· kg-1 · d-1 benazepril and 30 mg· kg-1 · d-1),with six 18-month-old make rats in each group.The experiments were conducted during a 4-month period.Blood pressure was monitored regularly.At the end of the experiments,we measured the levels of urine protein,urine creatinine,serum creatinine (SCR),blood urea nitrogen (BUN),and serum and renal cortex angiotensin Ⅱ (AngⅡ).Ultrastructural changes in the kidney were examined under light and transmission electron microscopy.The expressions of nephrin,LC3BⅡ,Atg5 and p62 in the glomerulus were analyzed by Western blot analysis.Results After treatment,the blood pressure and the urine albumin/creatinine ratio of the four SHR groups were still significantly higher than those of the NORM group,but the blood pressure and the urine albumin/creatinine ratio of the ARB group and the combined group were significantly lower than those of the CTRL group (all P< 0.05);There were no significant differences in SCR and BUN levels among these five groups (P> 0.05);The level of serum AngⅡ of the combined group was significantly higher than that of the CTRL group [CTRL (0.08±0.00) μg/L,Combined (0.12±0.01) μg/L,P<0.05];The levels of cortex AngⅡ of the four SHR groups were significantly lower than those of the NORM group,while the level of cortex AngⅡ of the ARB group was significantly higher than that of the CTRL group (all P<0.05);Renal ultrastructural examination revealed shrunken glomeruli,fused or effaced epithelial cell foot processes,and focal atrophy of renal tubules in the four SHR groups.These pathological changes were more serious in the CTRL group but less so in the combined group.There were significantly more autophagosomes in the NORM group and the combined group than in the CTRL group (P<0.05).Compared with the NORM group,the expressions of nephrin,LC3BⅡ,Atg5 and p62 in the CTRL group were suppressed significantly (P < 0.05).The expressions of nephrin,LC3BⅡ and Atg5 in the ACEI group and the expressions of nephrin,LC3BⅡ,Atg5 and p62 in the ARB group and the combined group were higher than in the CTRL group (P<0.05).Conclusions ACEI/ARB can decrease the autophagic activity of glomerular podocytes.The renal-protective effects of ACEI/ARB may be mediated by glomerular podocyte autophagy,which is induced by AngⅡ.
2.Effect of aging and hypertension on renal cortex angiotensin Ⅱ expression and podocyte autophagy in rats
Mingjiao PAN ; Mengyun XIAO ; Yang LYU ; Bo FU ; Lu YU ; Xiaodan WANG
Chinese Journal of Geriatrics 2016;35(4):421-426
Objective To study the changes of renal cortex angiotensin Ⅱ (AngⅡ) expression and podocyte autophagy in aging rats with normotension versus hypertension,to further investigate the possible mechanism of renal injury in hypertension during aging.Methods Normotensive Wistar-Kyoto-rats (WKYs) were allocated to three groups by age of 3-month-old group,13-month-old group,22-month-old group.Gender,age and number-matched spontaneously hypertensive rats (SHRs) served as controls.Blood pressure was monitored.Levels of urinary albumin,urinary creatinine,serum creatinine (SCR),blood urea nitrogen (BUN),Ang Ⅱ in serum and in renal cortex were detected.The kidney ultrastructural changes and podocyte autophagosomes were observed under light and transmission electron microscopy.Expressions of nephrin,LC3B Ⅱ,Atg5 and p62 in glomeruli were analyzed by Western blotting.Results Blood pressure was significantly higher in SHRs than in WKYs (P<0.05).During aging from 3-month-old to 13-month-old and to 22 monthold group,the urinary albumin/creatinine ratio was increased significantly in SHRs with hypertension and in WKYs with normotension [WKY:(0.12±0.01) g/mmol,(0.14±0.04) g/mmol vs.(0.34± 0.05) g/mmol;in SHR:(0.29±0.04) g/mmol,(0.31±0.05) g/mmol vs.(0.72±0.16) g/mmol,P<0.05],but SCR and BUN levels had no significant difference in SHRs and WKYs during aging (both P>0.05).And Ang Ⅱ levels in both serum and renal cortex had no significant change in normotension group during aging three time points (both P>0.05).An age-dependent decrease of Ang Ⅱ level in renal cortex appeared during aging three time points in hypertensive rats [SHR:(0.02 ±0.00) μg/L,(0.02±0.00) μg/L vs.(0.01±0.00) μg/L,P<0.05],but serum level of Ang Ⅱ had no significant difference during aging three time points (P> 0.05) in hypertension group.The structural changes,including glomerulosclerosis,tubular atrophy and interstitial fibrosis were observed during aging three time points both in normotensive and hypertensive rats,but these pathological changes were more serious in hypertensive rats.Autophagosomes relatively accumulated in aging normotensive rats.The protein expressions of LC3B Ⅱ,Atg5 and p62 were increased in normotensive rats during aging (all P<0.05).While the protein expressions of nephrin,LC3B Ⅱ,Atg5 and p62 were decreased in aging hypertensive rats (all P < 0.05).Conclusions Ang Ⅱ expression level in renal cortex is decreased during aging in hypertensive rats.Podocyte autophagic activity is relatively decreased during aging in normotensive rats,but is relatively increased during aging in hypertensive rats.Ang Ⅱ-induced podocyte autophagy may be involved in the pathogenesis of renal injury in hypertension during aging.
3.Euphorbia fischeriana extract reactivates latent HIV through nuclear factor-κB pathway.
Xiaoyan PAN ; Mingjiao ZHANG ; Xiaoyun ZENG ; Jian LIN ; Lin LI ; Minmin LI ; Wei ZHAO
Journal of Southern Medical University 2015;35(11):1614-1618
OBJECTIVETo investigate the effect of Euphorbia fischeriana extract on latent HIV reactivation and the pathway involved in this process and discuss the value of Euphorbia fischeriana extract in eliminating HIV.
METHODSFresh tissues of Euphorbia fischeriana root were crushed into powder after quick freezing with liquid nitrogen and extracted with acetone followed by a three-day vacuum freeze-drying for dehydration of the extract. The extract (EFE) was separated using RP-C18 column with high-performance liquid chromatography (HPLC) and identified with mass spectrometry (MS). The activity of reactivated latent HIV was analyzed by fluorescence-activated cell sorting in a J-Lat 10.6 cell model treated with EFE (50 µg/mL) for 24 h, using TNF-α (10 ng/mL) as the positive control. The effect of a NF-κB pathway inhibitor (Bay 11-7082) on EFE activity was tested. The changes in P65 expression in the cell nuclei within 2 h and HIV protein p24 expression within 24 h were analyzed by Western blotting in cells treated with EFE.
RESULTSEFE was obtained by one-step acetone extraction, and the concentration of prostratin in the extract was around 0.53 mmol/L. About 50% of the cells showed HIV reactivation after treatment with 50 µg/mL EFE for 24 h accompanied by a significantly increased p24 expression. The activity of EFE in reactivating latent HIV was inhibited by Bay 11-7082 in a concentration-dependent manner, and p65 accumulation was detected in the cell nuclei within 2 h.
CONCLUSIONEFE we obtained contains the active compounds of prostratin and its analogues and shows a strong capacity to reactivate latent HIV through classical NF-κB pathway.
Euphorbia ; chemistry ; Flow Cytometry ; HIV ; drug effects ; HIV Infections ; Humans ; NF-kappa B ; metabolism ; Nitriles ; Phorbol Esters ; chemistry ; Plant Extracts ; pharmacology ; Signal Transduction ; Sulfones ; Tumor Necrosis Factor-alpha ; Virus Latency ; drug effects
4.Risk factors analysis of true aneurysm formation of autogenous arteriovenous fistula in hemodialysis patients
Yafei BAI ; Ruman CHEN ; Mingjiao PAN ; Mingzhi XU ; Na AN ; Chunli WANG ; Hong LI
Chinese Journal of Nephrology 2022;38(7):583-588
Objective:To explore the risk factors of autogenous arteriovenous fistula (AVF) aneurysms (AVFAs) in maintenance hemodialysis (MHD) patients.Methods:The patients who used internal arteriovenous fistula (end to side anastomosis) of cephalic vein-radial artery at wrist as vascular access in Hainan Provincial People′s Hospital from June 1 to June 30, 2021 were selected as the research objects. The patients were divided into AVFAs group and non-AVFAs group according to whether AVF formed AVFAs. The clinical data and laboratory examination results between the two groups were compared. Binary logistic regression model was used to analyze the risk factors for the formation of AVFAs.Results:A total of 170 MHD patients were enrolled in this study, including 111 males (65.3%) and 59 females (34.7%), with age of (51.65±12.70) years old and dialysis age of (57.03±49.25) months. There were 33 cases in AVFAs group and 137 cases in non-AVFAs group. The incidence of AVFAs was 19.4%. Compared with non-AVFAs group, the proportion of males ( χ2=4.934, P=0.026) and the levels of serum uric acid ( t=2.547, P=0.012) and serum albumin ( t=2.122, P=0.010) in AVFAs group were higher; The age ( t=-2.210, P=0.028), the proportion of diabetes nephropathy ( χ2=11.788, P=0.001), systolic blood pressure ( t=-1.994, P=0.048) and total cholesterol ( t=-2.174, P=0.031) were lower; The diameter of anastomosis was wider ( Z=-3.224, P=0.001); Mantel-Haenszel chi square test analysis showed that dialysis age ( χ2=53.832, OR=0.518, P<0.001), AVF service time ( χ2=51.355, OR=0.516, P<0.001), and brachial artery blood flow ( χ2=25.315, OR=0.331, P<0.001) were correlated to the formation of AVFAs. The results of multivariate logistic regression analysis showed that males ( OR=10.005, 95% CI 1.875-53.394, P=0.007), longer dialysis age ( OR=1.341, 95% CI 1.104-1.628, P=0.003), longer AVF use time ( OR=1.187, 95% CI 1.002-1.405, P=0.047), higher brachial artery blood flow ( OR=1.002, 95% CI 1.000-1.004, P=0.028) and lower total cholesterol ( OR=0.388, 95% CI 0.172-0.875, P=0.022) were the independent risk factors for the formation of AVFAs. Conclusions:The incidence of AVFAs in MHD patients is 19.4%. Males, long dialysis age, long AVF use time, high brachial artery blood flow and low total cholesterol level are the independent risk factors for the formation of AVFAs.