Association of serum levels of secreted frizzled-related protein 5 and Wnt member 5a with glomerular filtration rate in patients with type 2 diabetes mellitus and chronic renal disease: a cross-sectional study

ABSTRACT BACKGROUND: Diabetic nephropathy is a common complication of chronic kidney disease (CKD). ­Inflammation in the kidneys is crucial for promoting development and progression of this complication. Wnt member 5a (Wnt5a) and secreted frizzled-related protein 5 (Sfrp5) are proinflammatory proteins associated with insulin resistance and chronic low-grade adipose tissue inflammation. OBJECTIVE: To determine the correlation between serum Sfrp5 and Wnt5a concentrations and glomerular filtration rate in patients with type 2 diabetes mellitus and CKD. DESIGN AND SETTING: Cross-sectional, comparative and observational study in the Department of Endocrinology, Civil Hospital, Culiacán, Sinaloa, Mexico. METHODS: Eighty individuals with chronic kidney disease were recruited. Their serum Sfrp5 and Wnt5a concentrations were quantified using the enzyme-linked immunosorbent assay (ELISA) test. The statistical analysis consisted of the Mann-Whitney U test for independent samples and Spearman correlation, with statistical significance of P < 0.05. RESULTS: Serum Sfrp5 concentration continually increased through the stages of CKD progression, whereas serum Wnt5a concentration presented its highest levels in stage 3 CKD. Negative correlations between estimated glomerular filtration rate (eGFR) and serum concentrations of Sfrp5 (r = -0434, P = 0.001) and Wnt5a (r = -0481, P = 0.001) were found. CONCLUSIONS: There were negative correlations between serum Sfrp5 and Wnt5a concentrations and eGFR at each stage of CKD, with higher levels in female patients. This phenomenon suggests that Sfrp5 and Wnt5a might be involved in development and evolution towards end-stage renal disease.

Effects of Wnt5A gene overexpression on cytoskeletal proteins of melanocytes / 中华皮肤科杂志

Objective To evaluate the effect of Wnt5A gene overexpression on cytoskeletal proteins of melanocytes after the plasmid containing the Wnt5A gene is transfected into primary melanocytes.Methods In vitro cultured primary human melanocytes were divided into three groups:blank control group receiving no treatment,negative control group transfected with endotoxin-free pcDNA3.1 (+)empty vector by Lipo3000 in Opti-MEM medium,Wnt5A plasnid group transfected with endotoxin-free pcDNA3.1 (+) vector containing the Wnt5A gene by Lipo3000 in Opti-MEM medium.After the transfection,quantitative PCR (qPCR) was performed to measure the mRNA expression of Wnt5A,ras-related C3 botulinum toxin substrate 1 (Rac1),filamentous actin (F-actin) and β-tubulin,Western blot analysis to determine the protein expression of Wnt5A,receptor tyrosine kinase like orphan receptor 2 (ROR2),Rac1,F-actin and β-tubulin,and an immunofluorescence assay (IFA) to observe the expression of cytoskeletal proteins.Results qPCR showed significant differences in the mRNA expression of the Wnt5A gene and its downstream genes Rac1 and F-actin among the Wnt5A plasmid group,negative control group and blank control group (F =1374.179,112.576,66.458,respectively,all P ＜ 0.01),but there was no significant difference in the mRNA expression of β-tubulin among the three groups (P ＞ 0.05).Additionally,the Wnt5A plasmid group showed significantly higher mRNA expression of Wnt5A,Rac1 and F-actin compared with the blank control group and negative control group (all P ＜ 0.05).As Western blot analysis revealed,compared with the blank control group and negative control group,the Wnt5A plasmid group showed significantly higher Wnt5A protein expression (both P ＜ 0.05),but significantly lower protein expression of Rac 1,ROR2 and F-actin (all P ＜ 0.05).However,no significant difference in β-tubulin protein expression was observed among the three groups (P ＞ 0.05).IFA showed no obvious difference in the fluorescence intensity of β-tubulin or F-actin between the Wnt5A group and the two control groups,but melanocytes showed larger size and increased number of dendrites,and the cytoskeleton changed dramatically with varying fluorescence intensity of F-actin,fuzzy texture,fractured or locally clustered tonofilaments in the Wnt5A group.Conclusion The overexpression of the Wnt5A gene in melanocytes can regulate the mRNA and protein expression of cytoskeletal proteins,nake melanocytes larger and more dendritic,and cause changes in the cytoskeleton,which may facilitate the transportation of melanosomes,and participate in the occurrence of hyperpigmented diseases.