Bone marrow mesenchymal stem cell-derived exosomal miR-30e-5p ameliorates high-glucose induced renal proximal tubular cell pyroptosis by inhibiting ELAVL1.

BACKGROUND: The rapid increase in the prevalence of diabetes has resulted in more cases of diabetic kidney disease (DKD). Treatment with bone marrow mesenchymal stem cells (BMSCs) may represent an alternative strategy to manage DKD. METHODS: HK-2 cells were treated with 30 mM high glucose (HG). Bone marrow MSC-derived exosomes (BMSC-exos) were isolated and internalized into HK-2 cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) and lactate dehydrogenase (LDH) assays were used to measure viability and cytotoxicity. The secretion of IL-1ß and IL-18 was measured by ELISA. Pyroptosis was assessed by flow cytometry. Quantitative RT-PCR was used to measure the levels of miR-30e-5p, ELAV like RNA binding protein 1 (ELAVL1), IL-1ß, and IL-18. The expression of ELAVL1 and pyroptosis-associated cytokine proteins was determined by western blot analysis. A dual-luciferase reporter gene assay was conducted to confirm the relationship between miR-30e-5p and ELAVL1. RESULTS: BMSC-exos decreased LDH, IL-1ß, and IL-18 secretion and inhibited the expression of the pyroptosis-related factors (IL-1ß, caspase-1, GSDMD-N, and NLRP3) in HG-induced HK-2 cells. Moreover, miR-30e-5p depletion derived from BMSC-exos promoted HK-2 cell pyroptosis. Besides, miR-30e-5p over-expression or ELVAL1 knockdown could directly inhibit pyroptosis. ELAVL1 was a target of miR-30e-5p and knocking down ELAVL1 reversed the effect of miR-30e-5p inhibition in BMSC-exos-treated HK-2 cells. CONCLUSIONS: BMSC-derived exosomal miR-30e-5p inhibits caspase-1-mediated pyroptosis by targeting ELAVL1 in HG-induced HK-2 cells, which might provide a new strategy for treating DKD.

Spectrum of biopsy-proven kidney diseases in northwest China: a review of 30 years of experiences.

PURPOSE: Large-scale, contemporary studies assessing the spectrum of kidney diseases in northwest China are lacking. Therefore, we aimed to assess the profile of 30-year temporal changes in biopsy-proven kidney diseases in northwest China. METHODS: This cross-sectional study included all patients with a native kidney biopsy specimen in the First Affiliated Hospital of Xi'an Jiaotong University between 1989 and 2018. Data on demographic characteristics and pathological diagnosis were extracted from medical records and pathological reports. Changing patterns of kidney diseases over the study period and disease distributions in different gender and age groups were examined. RESULTS: This study included 13,620 patients with a mean age of 38.5 ± 16.5 years and included 58.2% of men. Primary glomerulonephritis (PGN), second glomerulonephritis (SGN), tubulointerstitial disease, and other renal diseases accounted for 79.1, 18.3, 2.4, and 0.2% of all kidney diseases, respectively. In PGN, IgA nephropathy (IgAN) (25.1%) was the most common type, followed by non-IgA mesangial proliferative glomerulonephritis (MsPGN) (24.9%) and membranous nephropathy (MN) (17.4%). The frequency of MN dramatically increased (p < 0.001) over the course of the study. Lupus nephritis (6.2%) and Henoch-Schönlein purpura nephritis (HSPN) (4.9%) were leading SGN diagnosis. The frequencies of IgAN, non-IgA MsPGN, and HSPN declined, while those of ANCA/pauci-immune glomerulonephritis and diabetic nephropathy significantly increased. CONCLUSION: PGN continues to be the predominant kidney disease in northwest China, and IgAN is the most common type. The frequencies of MN and diabetic nephropathy significantly increased. These findings might be explained by behavioral and environmental exposures and provide implications on future hypothesis-driven research.

Inhibitory effect of oridonin on proliferation of RPMI8226 cells and the possible underlying mechanism.

OBJECTIVE: To observe the effects of oridonin on proliferation and apoptosis of myeloma RPMI8226 cells and to investigate the potential underlying mechanisms. METHODS: RPMI8226 cells were treated with various concentrations of oridonin. Cell proliferation was analyzed using the thiazolyl blue tetrazolium bromide method. Ultramicrostructure was observed by transmission electron microscopy. Annexin-V/PI staining and flow cytometry was performed to determine cell apoptosis. Expression of apoptosis-related proteins was evaluated by western blot analysis. RESULTS: Oridonin suppressed the proliferation of RPMI8226 cells and induced apoptosis in a time-and dose-dependent manner. Transmission electron microscopy confirmed apoptotic morphology upon treatment with 20 µmol/L oridonin and western blot revealed decreased expressions of the apoptosis suppressors survivin, Bcl-2 and pro-caspase-3 proteins, and the increased expression of the apoptosis inducer Bax. CONCLUSION: Our results show that oridonin exhibits an inhibitory effect on the proliferation of RPMI8226 cells and induces apoptosis. This is associated with altering the balance between Bcl-2 and Bax protein expressions and decreased survivin and pro-caspase-3 expressions.

Genetic polymorphisms in TNFSF13 and FDX1 are associated with IgA nephropathy in the Han Chinese population.

IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide, and its pathogenesis is influenced by both genetic and environmental factors. In this study, we evaluated 23 tag single-nucleotide polymorphisms (tSNPs) in 21 IgAN-associated genes, in 200 subjects with IgAN and 310 healthy gender- and age-matched unrelated control subjects with no history of renal disease or hypertension. Using the co-dominant model, we found that two genotypes of rs3803800 in TNFSF13 were associated with an increased risk of IgAN: "GA" (OR = 1.03, 95% CI = 0.71-1.51, p = 0.018) and "AA" (OR = 2.45, 95% CI = 1.29-4.65, p = 0.018). The "AA" genotype was also associated with an increased risk of IgAN in the recessive model (OR = 2.41, 95% CI = 1.30-4.46, p = 0.018), as was the genotype "AA" rs10488764 in FDX1 (OR = 1.88, 95% CI = 1.01-3.53, p = 0.048). Interestingly, we found that the allele "A" of rs3803800 in TNFSF13 is associated with a decreased risk of IgAN in females (OR = 0.43, 95% CI = 0.20-0.95, p = 0.009), but with an increased risk in males (OR = 1.78, 95% CI = 0.86-3.66, p = 0.009). Our findings, combined with previously reported results, suggest that TNFSF13 and FDX1 have potential roles in IgAN in the Han Chinese population. This information may be useful in the development of early prognostics for IgAN.

Association between CCDC132, FDX1 and TNFSF13 gene polymorphisms and the risk of IgA nephropathy.

AIM: Previous genome-wide association studies have identified multiple susceptibility loci for IgA nephropathy (IgAN); however, validation of these findings is still needed. METHODS: We performed a case-control study among 347 Chinese Han IgAN patients and 310 ethnicity-matched controls. Twenty-two single nucleotide polymorphisms (SNPs) were genotyped and association analysis was performed. RESULTS: We found three alleles for IgAN in patients: the allele "C" of rs2188404 in the CCDC132 gene by recessive model (odds ratio (OR), 1.65; 95% confidence interval (CI), 1.10-2.48; P = 0.014) and additive model (OR, 1.29; 95% CI, 1.03-1.61; P = 0.024) analysis, respectively, the allele "A" of rs10488764 in FDX1 gene by additive model (OR, 1.27; 95% CI, 1.00-1.61; P = 0.048) analysis, the allele "A" of rs3803800 in TNFSF13 gene by recessive model (OR, 2.05; 95% CI, 1.16-3.62; P = 0.010) and additive model (OR, 1.35; 95% CI, 1.06-1.72; P = 0.013) analysis, respectively. However, the associations between these SNPs and the risk of IgAN were not significant when adjusted for age and sex. Additionally, we found polymorphisms of rs2188404, rs10488764 and rs3803800 were correlated with urine protein (UPRO), human serum albumin (HSA), total cholesterol (TC) and Lee's pathological grades. CONCLUSION: We did not find any positive association between these SNPs and the risk of IgAN after adjustment by age and sex, but did find a significant and strong correlation with relevant clinical pathological parameters. Our study may provide a new perspective to understanding the aetiology of IgAN.

Uric acid-induced endoplasmic reticulum stress triggers phenotypic change in rat glomerular mesangial cells.

AIM: The aim of this study was to explore the contribution and the mechanism of uric acid (UA) to phenotypic change in rat glomerular mesangial cells. METHODS: Rat glomerular mesangial cells (HBZY-1) were exposed to UA (0.05 mmol/L to 0.4 mmol/L) for 24 h to 48 h. Subsequently, 4-phenyl butyric acid (4-PBA) (5 mg/dL) was added and 48 h incubation was performed. HBZY-1 cells exposed to UA (0.4 mmol/L) were incubated for 48 h. After incubation, the cells were examined under an inverted microscope and transmission electron microscope to observe their morphologies and the expressions of α-smooth muscle actin (α-SMA), transforming growth factor-ß1 (TGF-ß1), fibronectin (FN), glucose regulated protein 78 (GRP78), and the protein disulfide isomerase (PDI) proteins and mRNA in the HBZY-1 cells were measured by Western blot and reversed transcription-polymerase chain reaction. RESULTS: HBZY-1 cultured in UA showed evident morphological changes under transmission electron microscopy. The soluble UA stimulated the upregulation of the α-SMA, TGF-ß1 and FN mRNA and proteins in a concentration- and time-dependent manner. UA-induced endoplasmic reticulum (ER) stress, as evidenced by the upregulation of the mRNA and protein expressions of GRP78 and PDI. However, the upregulation was reverted by 4-PBA, an inhibitor of ER stress. CONCLUSIONS: Uric acid induces phenotypic change in HBZY-1 cells. ER stress plays a central role in UA-induced phenotypic transformation in vitro. 4-PBA may be beneficial in attenuating UA-induced glomerular injury.

Experimental research on treatment of injured facial nerves induced by hepatocyte growth factor mediated by ultrasound-targeted microbubble destruction.

The purpose of our study was to explore the regeneration effect of the ultrasound (US)-targeted microbubble destruction-mediated eukaryotic coexpression vector (pIRES2-enhanced green fluorescent protein [EGFP]/hepatocyte growth factor [HGF]) with EGFP and HGF gene system on facial nerve injury in rats. Forty rats were randomly divided into 4 groups after the models of facial nerve injury were established: A, phosphate-buffered saline (PBS) group; B, HGF and microbubble (HGF + MB) group; C, HGF and US (HGF + US) group; and D, HGF + US + microbubble (HGF + MB/US) group. Gene and protein levels of HGF were detected by quantitative real-time reverse transcriptase-polymerase chain reaction and Western blot, respectively. The expression of pEGFP in facial nerve trunks was examined by laser scanning confocal microscope; HGF gene and protein expression were significantly higher in D group compared with those of the other groups (P < 0.05). The expression of pEGFP was the strongest in D group (P < 0.05). These data indicate that US-targeted microbubble destruction effectively transfects the HGF gene into target tissues and has a significant effect on an injured facial nerve, thus providing a new strategy for gene therapy in facial nerve injury.