Upregulation of sFlt-1 by Trophoblasts Induces the Barrier Dysfunction of Glomerular Endothelial Cells

This study examined the effect of over-expression of sFlt-1 by trophoblasts on the barrier function of glomerular endothelial cells and the role of VEGF in this process in order to explore the pathogenesis of glomerular disease in preeclampsia. SFlt-1 expression in the human trophoblasts （TEV-1 cells） was enhanced by transfecting sFlt-1 plasmid DNA into TEV-1 cells. The monolayer barrier fimction of glomerular endothelial cells （ciGEnCs） was determined by measuring the fluorescence intensity of bovine serum albumin （BSA） that crossed the monolayer of glomerular endothelial cells. The results showed that the over-expression of sFlt-1 by TEV-1 cells led to the barrier dysfunction of ciGEnCs, and the exogenous VEGF could alleviate the ciGEnCs dysfunction resulting from the over-expression of sFlt- 1 to a certain extent. It was concluded that the dysregulation of sFlt- 1 and VEGF in preeclamptic pregnancy may contribute to the barrier dysfunction of glomerular endothelial cells, and VEGF may play an important role in maintaining the barrier function of glomerular endothelial cells, but it may not be the sole factor.

Effects of Maternal Serum on Permeability of Glomerular Endothelial Cell Membrane

The mechanism of injury on the human glomerular endothelial cells （ciGENC） induced by preeclampsia serum was investigated. Concentration of maternal serum sFlt-1 protein was detected by ELISA. Fluorescently-labeled bovine serum albumin infiltrating through lower chamber of Transwell was measured by multifunction microplate reader. Morphologic change of ciGENC was observed under inverted phase contrast microscope. The concentration of sflt-1 in preeclampsia groups was significantly increased as compared with control group （P〈0.01）. Permeability in preeclampsia groups was significantly increased as compared with control group （P〈0.01）. By contrast with severe preeclampsia group, the permeability of ciGENC monolayer in mild preeclampsia group was decreased significantly （P〈0.05）. Intervention of exogenous VEGF significantly decreased permeability of ciGENC in preeclampsia groups. It was concluded that sFlt-1 increased ciGENC permeability by damaging integrity of endothelial barrier function.

The Effects of Glomerular Endothelial Cell Autophagy on Diabetic Nephropathy

Diabetic nephropathy is one of the most common causes of end-stage renal disease worldwide and is associated with increased mortality in patients with type 1 and type 2 diabetes.Autophagy is a highly conserved"autophagy"pathway and is an important mechanism for maintaining glomerular and tubular homeostasis.Emerging evidence suggests that targeted autophagy pathway activation and restoration of autophagy activity may have renal protection.Glomerular endothelial cells are an important key factor in the development of diabetic nephropathy.Endothelial dysfunction is involved in the development of diabetic and non-diabetic glomerular injury and renal fibrosis.Evidence of glomerular endothelial dysfunction in the late stages of diabetic nephropathy,such as thrombotic microangiopathy,including impairment of glomerular capillary microaneurysms and glomerular membrane lysis autophagy,is related to the pathogenesis of diabetic nephropathy.Here,we mainly introduced the research progress of the effects of glomerular endothelial cell autophagy on diabetic nephropathy.

Protective Effects of Combination of Radix Astragali and Radix Salviae Miltiorrhizae on Kidney of Spontaneously Hypertensive Rats and Renal Intrinsic Cells

Objective: To evaluate the effects of combination of Radix Astragali(RA) and Radix Salviae Miltiorrhizae(RS) on kidney of spontaneously hypertensive rats(SHRs) and renal intrinsic cells. Methods: SHRs were intragastrically administrated with RA(5.09 g/kg) and RS(2.55 g/kg) either alone or with combination for 4 weeks;valsartan(13.35 mg/kg) was used as a positive control. Blood pressure and renal ultrasonography were monitored periodically. The biomarkers [microalbumin(m ALB), cystatin C, angiotensin Ⅱ(Ang Ⅱ), interleukin-1 beta(IL-1β), and β2-microglobulin(β2-Mg), etc.] in serum and urine were measured by enzyme-linked immunosorbent assay(ELISA). The protein expressions [phosphorylated adenosine 5’-monophosphate-activated protein kinase-α1(p-AMPKα1), sestrin-β, calcium/calmodulin-dependent protein kinase kinase-β(Ca MKK-β), phosphoinositide 3-kinases(PI3 K), serine-threonine protein kinase 1(AKT1), and vascular endothelial growth factor receptor 2(VEGFR2)] in renal cortex were determined by Western blot. In vitro, the hypertensive cellular model was established by applying 2×10^-6 mol/L Ang Ⅱ. The primary human podocytes, human glomerular endothelial cells(HRGECs), and human proximal tubular epithelial cells(HK-2 s) were pre-incubated with sulfotanshinone sodium(Tan, 10 μg/m L) and/or calycosin-7-O-β-D-glucoside(Cal, 5 μg/m L). The cellular viability and apoptosis were assayed by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide(MTT) and Annexin V/PI staining, respectively. The level of endothelial nitric oxide synthase(eNOS) in culture supernatant was determined by ELISA. Results: RA+RS significantly decreased the diastolic blood pressure, renal vascular resistance index, and parenchymal thickness, increased 24 h urinary volume as well as lowered the levels of urine m ALB and serum cystatin C, IL-1β and β2-Mg of SHRs(P<0.05 vs. SHRs). The decreased protein levels of p-AMPKα1, sestrinβ and Ca MKK-β and the increased protein levels of PI3 K, AKT1 and VEGFR2 in renal cortex of SHRs were normalized after RA+RS treatment(P<0.05). In vitro, Tan and Cal attenuated the Ang Ⅱ-induced abnormal proliferation and increased the apoptosis of HRGECs and HK-2 s and improved the level of e NOS in culture supernatant. Whereas, neither of them showed powerful effect on podocyte. Conclusion: The combination of RA and RS had potential effects on alleviating the renal damages of SHRs and the renoprotection was independent of blood pressure level.