Kidney hemodynamic function in men and postmenopausal women with type 2 diabetes and preserved kidney function

Unraveling Sex Differences in Kidney Health and CKD: A Review of the Effect of Sex Hormones

Sexual dimorphism plays an important role in the pathogenesis and progression of CKD. Men with CKD often exhibit faster kidney function decline, leading to higher rates of kidney failure and mortality compared with women. Studies suggest that sex hormones may influence this apparent dimorphism, although the mechanisms underlying these influences remain poorly understood. In this review, we first summarize recent findings on sex differences in the prevalence and progression of CKD. Subsequently, we will focus on ( 1 ) the role of sex hormones in these sex differences, ( 2 ) kidney structural and hemodynamic differences between men and women, ( 3 ) the influence of sex hormones on pathophysiological processes leading to kidney disease, including glomerular hyperfiltration and key pathways involved in kidney inflammation and fibrosis, and finally, focus on the consequences of the underrepresentation of women in clinical trials. Understanding these sex differences is critical for advancing precision medicine and improving outcomes for both men and women with CKD.

Intact mitochondrial substrate efflux is essential for prevention of tubular injury in a sex-dependent manner

The importance of healthy mitochondrial function is implicated in the prevention of chronic kidney disease (CKD) and diabetic kidney disease (DKD). Sex differences also play important roles in DKD. Our previous studies revealed that mitochondrial substrate overload (modeled by homozygous deletion of carnitine acetyl-transferase [CrAT]) in proximal tubules causes renal injury. Here, we demonstrate the importance of intact mitochondrial substrate efflux by titrating the amount of overload through the generation of a heterozygous CrAT-KO model (PT-CrATHET mouse). Intriguingly, these animals developed renal injury similarly to their homozygous counterparts. Mitochondria were structurally and functionally impaired in both sexes. Transcriptomic analyses, however, revealed striking sex differences. Male mice shut down fatty acid oxidation and several other metabolism-related pathways. Female mice had a significantly weaker transcriptional response in metabolism, but activation of inflammatory pathways was prominent. Proximal tubular cells from PT-CrATHET mice of both sexes exhibited a shift toward a more glycolytic phenotype, but female mice were still able to oxidize fatty acid-based substrates. Our results demonstrate that maintaining mitochondrial substrate metabolism balance is crucial to satisfying proximal tubular energy demand. Our findings have potentially broad implications, as both the glycolytic shift and the sexual dimorphisms discovered herein offer potentially new modalities for future interventions for treating kidney disease.