Expression of fibrosis-associated molecules in IgA nephropathy treated with cyclosporine

Risk factors for Encapsulating Peritoneal Sclerosis in patients undergoing peritoneal dialysis: A meta-analysis

Purpose

Encapsulating Peritoneal Sclerosis (EPS) is the most serious complication of long-term peritoneal dialysis (PD), which considerably reduces the patient’s quality of life, leading to patients discontinuing PD. Considering these negative effects, it is necessary to systematically review and determine the risk factors of EPS.

Methods

The PubMed, Embase, Web of Science, Cochrane Library, and China Biology Medicine (CBM) were searched from their inception to January 1st, 2022, and the bibliographies from the citations of relevant articles were manually searched. The ROBINS-I (Risk of Bias in Non-randomized studies of Interventions) tool was used to evaluate the risk of bias of included studies.

Results

Ten studies involving 12595 participants were included in this meta-analysis. The results revealed that a younger age at PD onset (MD = -7.70, 95% CI, -11.53~-3.86), a higher transporter (MD = 0.13, 95% CI, 0.09~0.18), a longer PD duration (SMD = 1.15, 95% CI, 0.68~1.61), a longer peritonitis duration (MD = 12.66, 95% CI, 3.85~21.47), and history of glomerulonephritis (OR = 1.42, 95% CI, 1.02~1.97) were significant risk factors for EPS. However, sex, use of icodextrin, the number of peritonitis episodes, and history of multicystic kidney disease did not affect the risk of EPS.

Conclusions

This review provides a scientific basis for further understanding the etiology of PD-related EPS and improving prevention strategies. More high-quality studies are necessary to validate this paper’s findings.

The role of endoglin in kidney fibrosis

Tubulointerstitial fibrosis and glomerulosclerosis, are a major feature of end stage chronic kidney disease (CKD), characterised by an excessive accumulation of extracellular matrix (ECM) proteins. Transforming growth factor beta-1 (TGF-β1) is a cytokine with an important role in many steps of renal fibrosis such as myofibroblast activation and proliferation, ECM protein synthesis and inflammatory cell infiltration. Endoglin is a TGF-β co-receptor that modulates TGF-β responses in different cell types. In numerous cells types, such as mesangial cells or myoblasts, endoglin regulates negatively TGF-β-induced ECM protein expression. However, recently it has been demonstrated that 'in vivo' endoglin promotes fibrotic responses. Furthermore, several studies have demonstrated an increase of endoglin expression in experimental models of renal fibrosis in the kidney and other tissues. Nevertheless, the role of endoglin in renal fibrosis development is unclear and a question arises: Does endoglin protect against renal fibrosis or promotes its development? The purpose of this review is to critically analyse the recent knowledge relating to endoglin and renal fibrosis. Knowledge of endoglin role in this pathology is necessary to consider endoglin as a possible therapeutic target against renal fibrosis.

Protection of rhein on IgA nephropathy mediated by inhibition of fibronectin expression in rats

Objective:

To investigate the protective effects of rhein on IgA nephropathy (IgAN) in the rat model.

Materials and Methods:

Twenty-eight female sprague dawley rats were divided randomly into four groups, namely control, IgAN, rhein-prevented and rhein-treated. The pathologic changes on renal tissue were observed by the H and E, staining and the amount of urinary red blood cells and 24-h urinary protein excretion were measured. The glomerular deposition of immune globulin A (IgA) was measured by immunofluorescence staining. Fibronectin (FN) and α-smooth muscle actin (α-SMA) expression on renal tissue were measured via immunohistochemistry.

Results:

The model of IgAN was established according to Bovine serum albumin-Lipopolysaccharide-Carbon tetrachloride protocol, which was evidenced by histological structural lesions of glomeruli, IgA deposition and urinary measurement. Histological examination of kidney sections from both rhein-prevented group and rhein-treated group showed that glomerular hypertrophy, mesangial expansion, excessive extracellular matrix, and renal capsule dilation were markedly ameliorated compared with IgAN group. Moreover, rhein treatment significantly reduced IgA deposition in glomerulus, the volume of urinary red blood cells and 24-h urinary protein excretion. More importantly, increased FN expression in IgAN was back to normal level in rhein-prevented and rhein-treated group, which was along with the reduction of α-SMA expression in renal tissues.

Conclusions:

These findings indicate that rhein prevents the development of glomerulosclerosis and halts the progression of IgAN via inhibition of FN and α-SMA expression.

Comparison of glucocorticoids alone and combined with cyclosporine a in patients with IgA nephropathy: a prospective randomized controlled trial

OBJECTIVE

The aim of this study was to investigate the effects of two different treatment regimes in patients with IgA nephropathy (IgAN): steroids alone and in combination with a medium dose of cyclosporine A (CsA).

METHODS

Forty-eight IgAN patients 18-69 years of age with proteinuria >1.0 g/24 hours and an estimated glomerular filtration rate (eGFR) of >30 mL/min/1.73 m(2) were randomly given either steroids alone (methylprednisolone (MP) group; n=25) or steroids plus CsA treatment (combination group; n=23). The primary endpoint was the reduction of proteinuria by 50% or more of the baseline value. The secondary endpoint was an increase in the baseline serum creatinine level of 50% or a decrease in the baseline eGFR of 25%.

RESULTS

After 12 months of treatment, all patients in the combination group and 87.50% of the patients in the MP group reached the primary endpoint. The complete remission rates in the combination group and MP group were 50.0% and 45.83%, respectively. The level of urinary protein excretion declined from 3.17 ± 3.25 g/24 hours to 0.36 ± 0.23 g/24 hours (p<0.001) in the combination group and from 2.60 ± 2.03 g/24 hours to 0.53 ± 0.71 g/24 hours (p<0.001) in the MP group. Two patients in the combination group reached the secondary endpoint, with a decrease in the eGFR of 25% from the baseline value, while no patients in the MP group achieved this goal. The patients in the combination group exhibited significant improvements in the eGFR after nine months (90.16 ± 28.78 vs. 80.46 ± 22.73 mL/min.1.73 m(2), p=0.011), while the patients in the MP group showed significant increases in the eGFR after six months of treatment (92.18 ± 22.71 to 81.63 ± 18.36 mL/min/1.73 m(2), p=0.019). Four patients (8.33%) developed severe pneumonia during treatment.

CONCLUSION

Both the full dose of steroids alone and combined treatment with steroids and a medium dose of CsA remarkably reduced the levels of proteinuria and ameliorated the renal function in the IgAN patients. Infection was the most serious complication during the treatment.

Bufalin inhibits platelet-derived growth factor-BB-induced mesangial cell proliferation through mediating cell cycle progression

Bufalin, a traditional Chinese medicine, has been reported as a protective factor in many tumors. We therefore investigated the effect of bufalin on platelet-derived growth factor (PDGF)-BB-induced proliferation of cultured rat mesangial cells. The effect of bufalin on cell proliferation and its underlying mechanisms were investigated in cultured rat mesangial cells (MCs) by the methylthiazoletetrazolium (MTT) assay, flow cytometry, reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, and cyclin-dependent kinases (CDK)2 and CDK4 kinase assays. Bufalin inhibited 20 ng/ml PDGF-BB-induced MC proliferation in a dose-dependent manner. Similar results were observed in different concentrations of bufalin, which blocked PDGF-BB-induced progression through G0/G1 to S phase of the cell cycle. Furthermore, bufalin not only inhibited upregulation of cyclin D1 and CDK4, but also downregulation of p21 in both mRNA and protein levels. Although bufalin did not affect p27 and CDK2 mRNA expression, it reversed downregulation of p27 and upregulation of CDK2 in protein level. Activity of CDK2 and CDK4 was also inhibited by bufalin. However, both bufalin and PDGF-BB did not affect cyclin E mRNA or protein expression. These results suggest that bufalin could inhibit MC proliferation by modulating cell cycle progress, indicating that bufalin could be a potential therapeutic agent for the prevention of mesangial proliferative glomerulonephritis.