From cause to relief: Vitamin D plays a crucial role in overactive bladder via the RhoA/ROCK signaling pathway

Overactive bladder (OAB) is a common urological disorder, characterized by urinary urgency and frequency. However, the etiology and pathogenesis of OAB remain unclear. The objective of this study was to construct a Vitamin D-deficient rat model with the aim of clarifying the relationship between Vitamin D deficiency and the development of OAB, as well as investigating the potential mechanisms involved. The findings revealed that rats with vitamin D deficiency exhibited indications of OAB, including increased urinary frequency and urgency, as evidenced by void spot assay and cystometry. Furthermore, supplementation with vitamin D proved to be an effective intervention in alleviating these symptoms. The activation of RhoA/ROCK pathway was found in the bladder tissues and urine of rats with vitamin D deficiency. Moreover, supplementation with vitamin D led to a significant decrease in the expression levels of RhoA/ROCK pathway in both bladder tissue and urine. In conclusion, our study was the first to demonstrate that vitamin D deficiency is one of the etiological factors of OAB through the activation of the RhoA/ROCK signaling pathway, and that vitamin D supplementation has been shown to effectively alleviate OAB symptoms by inhibiting this pathway. Meanwhile, urinary RhoA may be a biomarker of OAB. Our present work makes a significant contribution to the clarification of the etiology and mechanism of OAB, as well as to the refinement of OAB treatment strategies.