BioProject

Aging affects multi-organ systems. What local and systemic factors influence renal structure and function in aging are not well understood. More...

Aging affects multi-organ systems. What local and systemic factors influence renal structure and function in aging are not well understood. We and others have shown that the secretory protein, C1q/TNF-related protein 1 (CTRP1), regulates systemic metabolism and cardiovascular function. Whether CTRP1 has a role in kidney function is unknown. We provide evidence here that CTRP1 modulates renal physiology in an age- and sex-dependent manner. In addition to adipose tissue, CTRP1 is also expressed in kidney glomeruli, with podocyte being a major cell source. In mice lacking CTRP1, we observed significant increase in kidney weight and glomeruli hypertrophy in aged (~1 year) male, but not female or younger mice. Although glomerular filtration rate, plasma renin and aldosterone levels, and renal response to water restriction are not different between genotypes, aged CTRP1-deficient male mice have elevated blood pressure. Echocardiogram and pulse wave velocity measurements indicate normal heart function and vascular stiffness in CTRP1 knockout animals. Increased blood pressure is not due to greater salt retention. Paradoxically, CTRP1-deficient mice have elevated urinary sodium and potassium excretion, resulting, in part, from reduced expression of genes involved in renal sodium and potassium reabsorption. Despite renal hypertrophy, gene expression related to inflammation, fibrosis, and oxidative stress are significantly lower in CTRP1-deficient mice. RNA sequencing and pathway analyses reveal additional alterations and enrichments of genes in metabolic processes in the kidney of CTRP1-null animals. These results highlight novel contributions of CTRP1 to aging-associated changes in renal structure and function Overall design: Kidney RNA sequenceing and bioinformatics analyses were performed on age-matched 49 week-old wildtype (WT) and CTRP1-/- mice, with 4 biological replicates for each genotype. Less...