A modified elliptical formula to estimate kidney collagen content in a model of chronic kidney disease

MiR-1297 attenuates high glucose-induced injury in HK-2 cells via targeting COL1A2

BACKGROUND

In this study, we aimed to explore whether COL1A2 and miR-1297 participated in the progression of diabetic nephropathy (DN) in vitro and classified the underlying mechanisms.

METHODS

d-Glucose (30 mM; high glucose, HG)-stimulated HK-2 cells were used to mimic DN condition. RNA and non-coding RNA profiles were from Gene Expression Omnibus (GEO) database. The interaction between miR-1297 and COL1A2 was measured by dual-luciferase reporter assay. Gene Set Enrichment Analysis (GSEA) method was conducted to analyse COL1A2-associated signalling pathways. The role of miR-1297/COL1A2 in biological behaviours of HG-induced HK-2 cells were analysed by cell counting kit-8 and apoptosis assays.

RESULTS

Bioinformatics analysis revealed that COL1A2 was up-regulated in DN tissues. We predicted and verified miR-1297 as the regulatory miRNA of COL1A2, and the expression of miR-1297 was decreased in DN tissues and HG-stimulated HK-2 cells. Overexpression of miR-1297 could promote cell proliferation and inhibit apoptosis to protect HK-2 cells from HG-induced damage. And knockdown of COL1A2 enhanced the protective effects of miR-1297 on HG-stimulated HK-2 cells. GSEA results revealed that several inflammatory pathways were enriched in COL1A2 high-expression group. Meanwhile, transfection of miR-1297 reduced the phosphorylation of NFκB and expression of three important pro-inflammatory genes including cytokine CCL5, adhesion molecules ICAM1 and VCAM1 via targeting COL1A2. These results suggested that miR-1297 protected HG-treated HK-2 cells probably through suppressing inflammation via targeting COL1A2.

CONCLUSION

This study sheds a light on the role miR-1297/COL1A2 in DN progression and provides a novel promising therapy strategy for suppressing DN progression.

Nephropathy induced by renal microembolism: a characterization of biochemical and histopathological changes in rats

The aim of this study was to investigate some biochemical parameters of renal function and the vascular, glomerular, tubular, and interstitial manifestations in the progression of nephropathy induced by renal microembolism. Renal microembolism was induced by the arterial injection of polymethacrylate microspheres in the remnant kidney of nephrectomized rats. Animals 110-120 days old were randomly divided into three groups: the control group (C; normal), the nephrectomized group (S; nephrectomized that did not undergo renal microembolism), and the model group (M, nephrectomized animals that underwent renal arterial microembolism). The animals were evaluated 30, 60, and 90 days after the induction of a renal microembolism. Blood and urine samples were collected to determine serum creatinine (Cr) and urea (Ur) concentrations and urine total protein (Pt) concentrations. The kidneys were weighed and processed for histopathological analysis using hematoxylin and eosin (HE), periodic acid-Schiff (PAS), Mallory-Azan, and Picro-Sirius staining. The samples were also subjected to immunohistochemistry with a proliferating cell nuclear antigen (PCNA) and a vascular endothelial growth factor receptor (VEGFR). The data demonstrated evidence of the occurrence of vascular, glomerular, tubular, and interstitial abnormalities in the renal tissue, and changes in the biochemical parameters of renal function (serum Cr and Ur and of 24-h urine Pt) in this experimental model of nephropathy induced by renal microembolism, which may indicate the development of chronic kidney disease (CKD). Additionally, the findings indicate that this is a good reproducibility model that may be useful for studying the pathogenesis of CKD that is caused by atheroembolism and possible treatment alternatives.