Salidroside Attenuates Hypoxia-Induced Expression of Connexin 43 in Corpus Cavernosum Smooth Muscle Cells

Abstract

Introduction: Connexin 43 (Cx43) is the major component of gap junction in corpus cavernosum smooth muscle, which allows rapid intercellular communication. Cx43 coordinates corpus cavernosum smooth muscle cells and ensures erectile function. The role of hypoxia in Cx43 dysfunction resulting in erectile dysfunction has not been well studied, and salidroside has shown cell protective effects under hypoxia. Objective: We aimed to investigate the protective role of salidroside and the underlying mechanisms in hypoxia-induced dysfunction of Cx43. Methods: Corpus cavernosum smooth muscle cells prepared from young male Sprague-Dawley rats were pretreated with or without salidroside and exposed to hypoxic condition for 48 h. The cell viability, expression of hypoxia-inducible factor-1α (HIF-1α) and Cx43, and Ca²⁺ signals were investigated. Results: Pretreatment with salidroside attenuated loss of hypoxia-induced cell viability markedly and could downregulate the HIF-1α protein expression under hypoxia. Moreover, the expression of Cx43 was significantly increased by hypoxia but was decreased with salidroside pretreatment. The salidroside pretreated group exhibited enhanced release of intracellular Ca²⁺ in corpus cavernosum smooth muscle cells compared with the hypoxia group after stimulation. Conclusion: Salidroside has a protective effect against hypoxia-induced damage to corpus cavernosum smooth muscle cells.