Comparative analysis of cytoskeletal proteins and the sarcoglycan complex in the cremaster muscle of patients with retractile and undescended testis

Abstract

Introduction

The cremaster muscle plays a crucial role in testicular mobility and thermoregulation. Structural and functional alterations of this muscle have been implicated in the pathophysiology of undescended testis. Previous studies have demonstrated a significant impairment of the cytoskeleton in cremasteric smooth muscle cells in patients with cryptorchidism. This alteration may explain the muscular dysfunction involved in testicular descent. The aim of this study was to assess and quantify the expression of sarcoglycans, as well as the anchoring proteins vinculin and talin, in the cremaster muscle of children with undescended testis.

Materials and methods

Cremaster muscle samples were obtained from pediatric patients undergoing surgery for undescended testis, retractile testis, or inguinal canal pathologies (control group). Immunofluorescence analysis was used to evaluate the expression of alpha-, beta-, gamma-, delta-, and epsilon-sarcoglycans, as well as talin and vinculin. Signal intensity was quantified and compared among the groups.

Results

All analyzed markers showed significantly higher expression in the retractile group, followed by the control group and, lastly, the undescended testis group. The differences among groups were statistically significant (p < 0.05), with a consistent trend: retractile > control > undescended.

Conclusions

The molecular profile of the cremaster muscle in patients with undescended testis shows poorer structural preservation compared to the other groups, with reduced expression of sarcolemmal and anchoring proteins relative to the retractile and control groups. This molecular pattern suggests a structural and functional impairment of the cremaster muscle, rendering it non-retractile. These findings support the concept that undescended testis is not merely an anatomical variant or a retractile testis awaiting descent, but rather a condition characterized by more profound structural alterations.