GDF11 Improves Ischemia-Reperfusion-Induced Acute Kidney Injury via Regulating Macrophage M1/M2 Polarization.

INTRODUCTION: Acute kidney injury (AKI) is a clinical emergency caused by the rapid decline of renal function caused by various etiologies. Growth differentiation factor 11 (GDF11) can promote renal tubular regeneration and improve kidney function in AKI, but the specific mechanism remains unclear. Herein, we investigated the effect and mechanisms of GDF11 in ameliorating AKI induced by ischemia-reperfusion (I/R). METHODS: An animal model of AKI was established by I/R method, and the changes of serum urea nitrogen and creatinine were measured to evaluate the AKI. Enzyme-linked immunosorbent assay (ELISA) was used to measure cytokines, malondialdehyde, superoxide dismutase, nitric oxide synthase, and arginase 1 levels. Flow cytometry was used to count the M1/M2 macrophages. IHC, WB, and q-PCR experiments were used to evaluate the expression of GDF11. RESULTS: The changes in serum levels of urea nitrogen and creatinine after I/R suggest that an animal model of AKI induced by I/R was successfully established. AKI caused by I/R significantly changed the M1/M2 macrophage polarization balance, with an increase in M2 being significantly higher than M1 as well as increased oxidative stress. Treatment with GDF11 after I/R significantly increased the differentiation of M2 cells and inhibited the differentiation of M1 macrophages, as well as decreased oxidative stress. CONCLUSION: GDF11 can promote the repair of AKI caused by I/R by regulating the balance of M1/M2 polarization in macrophages and oxidative stress.

[Association between hypertriglyceridemic waist?to?height ratio phenotype and chronic kidney disease in a community population in South China: a cross-sectional study].

OBJECTIVE: To investigate the relationship between hypertriglyceridemic waist to height ratio phenotype (HWHtR) and chronic kidney disease (CKD) in a community population in South China. METHODS: A cross sectional study was conducted among 2142 residents in Zhuhai (Guangdong Province, China) from June to October of 2012. The HWHtR phenotype was defined as a waist to height ratio(WHtR) ≥0.55 and triglyceride level ≥2.0 mmol/L, based on which the participants were divided into HWHtR group and nonHWHtR group. CKD was defined as an eGFR<60 mL/min per 1.73 m2 or an ACR ≥30 mg/g. A logistic regression model was established to investigate the relationship between chronic kidney disease and HWHtR phenotype. RESULTS: Compared with the nonHWHtR group, the HWHtR group had a higher prevalence of chronic kidney disease (11.1% vs 33%, P<0.001). Analysis using the logistic regression model showed that HWHtR was significantly associated with CKD in the unadjusted analyses (OR=3.23, 95% CI: 2.32-4.48, P<0.001). After adjustment for age, sex, history of hypertension, history of diabetes, systolic blood pressure, diastolic blood pressure, drinking, physical exercise, education and current smoking, HWHtR was significantly associated with CKD (OR=2.36, 95% CI: 1.52-3.67, P<0.001); the association of HWHtR and CKD was still significant after further adjustment for BMI (OR=2.12, 95%CI: 1.34-3.35, P<0.001). CONCLUSION: Our finding suggests that HWHtR is associated with CKD in this community population.

[Clinical and pathological features in IgA nephropathy with IgG deposition in the glomerular mesangial area].

OBJECTIVE: To investigate the relationship between the clinical and pathological findings in IgA nephropathy with or without IgG deposition in the glomerular mesangial area. METHODS: The data were collected from 122 patients with a diagnosis of IgA nephropathy by renal biopsy in the Third Affiliated Hospital of Southern Medical University between November, 2009 and February, 2016. All the samples were examined by light microscopy, immunofluorescence and electron microscopy. According to the results of immunofluorescence assay, the patients were divided into IgA group (n=63) and IgA-IgG group (n=59). The pathological classification of IgA nephropathy was analyzed according to Oxford classification and Lee's classification. The clinical and pathological findings were compared between the two groups. RESULTS: Compared with the patients with IgA nephropathy but without IgG deposition, patients with IgA nephropathy with IgG deposition had higher serum creatinine, higher 24-h urine protein, higher blood uric acid, higher triglyceride levels (P<0.05) and lower eGFR (P<0.05); more of these patients were in Lee's grade IV-V, had renal tubular atrophy and/or interstitial fibrosis, and had MEST scores more than 3 (P<0.05). CONCLUSION: Patients with IgA nephropathy with IgG deposition in the glomerular mesangial have severer clinical symptoms and more serious pathological changes. Measures should be taken to control IgG deposition in patients with IgA nephropathy to delay the progress of the disease.

[Detection of PLA2R1 in renal biopsy specimens of patients with idiopathic membranous nephropathy].

OBJECTIVE: To investigate the prevalence of PLA2R1 in renal biopsy specimens of patients with idiopathic membranous nephropathy (IMN) and explore the relationship between PLA2R1 and IMN. METHODS: A total of 108 adult patients with biopsy-proved glomerular diseases were enrolled in this study, including 41 with IMN, 2 with hepatitis B-associated membranous nephropathy, 8 with V lupus nephritis, 27 with IgA nephropathy, 19 with minimal change nephropathy, 5 with mild mesangial proliferative glomerulonephritis, and 6 with focal segmental glomeruloselerosis (FSGS). Indirect immunofluorescence assay was used to detect PLA2R1 in the biopsy specimens and the clinical variables of the IMN patients were analyzed. RESULTS: In 35 of the 41 (85.37%) patients with IMN, PLA2R1 was detected with a fine granular pattern in the subepithelial deposits along the glomerular capillary loops. PLA2R1 antigen was not detected in patients with other glomerulopathies. No significant differences were found in age, serum creatinine, serum albumin, or 24-h urinary protein level between PLA2R1-positive and negative patients with IMN (P>0.05). CONCLUSION: According to our results, 85.37% of adult patients with biopsy-proven IMN are positive for PLA2R1 antigen, which, however, does not contribute to variations of the patients' clinical manifestations.

Prevalence and distribution of metabolic syndrome in a southern Chinese population. Relation to exercise, smoking, and educational level.

OBJECTIVE: To investigate the prevalence and distribution of metabolic syndrome (MetS) and the impact of exercise, smoking, and educational level on the risk of MetS in a southern Chinese population. METHODS: A cross-sectional study was conducted in Zhuhai City, China from June to August 2012. Data on exercise, smoking, and educational level, anthropometric parameters, blood pressure, lipid, and glucose levels were collected. The prevalence of MetS (as defined by the International Diabetes Federation) was determined. Data necessary to evaluate MetS, the socio-economic characteristics, and lifestyle were obtained for 4645 subjects aged 18-75 years old. RESULTS: A total of 19.8% of the participants had MetS. The adjusted odds of having MetS were lower among males (adjusted odds: 0.75; 95% confidence interval [CI]: 0.57-1.01) compared with females. Those participants who currently smoked had a higher risk of developing MetS compared with non-smokers (adjusted odds: 1.61; 95% CI: 1.13-2.50). Those who had no physical exercise had a higher risk of developing MetS compared with those who physically exercised more than 60 minutes/day (adjusted odds: 1.51; 95% CI: 1.12-2.23;). Compared with those with no education, every category of attained educational level had a lower risk of developing MetS (p<0.001). CONCLUSION: The findings in this study revealed that current smokers had a greater risk of developing MetS compared with non-smokers. Increased physical activity and higher levels of education attained served as protective factors for the population.