Non-obstructive azoospermia and shortened leukocyte telomere length: further evidence linking poor health and infertility

Galectin-1 (Gal-1) and Galectin-3 (Gal-3) levels in seminal plasma and serum in azoospermic patients versus fertile men: A cross-sectional study

INTRODUCTION

Galectin-1 (Gal-1) and galectin-3 (Gal-3) are expressed by many immune cells and receive considerable attention in the context of immunity. We aimed to compare between seminal plasma and serum levels of Gal-1 and Gal-3 in azoospermic patients and fertile men.

MATERIALS AND METHODS

This cross-sectional study was conducted at the andrology outpatient clinic from January (2022) to September (2022). A total of 90 participants were enrolled and divided into two equal groups: azoospermic and normal group. Semen analysis was done for all participants. Hormonal profile including FSH, LH, serum prolactin, total testosterone and estradiol was performed as well as assessment of serum and seminal levels of Gal-1 and Gal-3 by ELISA commercial kits. Finally, scrotal Duplex was done in standing and supine position.

RESULTS

Serum and seminal levels of Gal-1 and Gal-3 were statistically significant higher in azoospermic patients compared with normal individuals (p < 0.001 for all). In addition, in healthy individuals there were statistically significant positive correlations between serum levels of Gal-1 and age, FSH, LH levels (r = 0.296, p = 0.005; r = 0.333, p = < 0.001; r = 0.312, p = 0.003, respectively) and serum levels of Gal-2 and FSH and LH (r = 0.436, p < 0.001; r = 0.350, p < 0.001, respectively), whereas serum Gal-3 showed a borderline positive correlation with age (r = 0.2, p = 0.059). Additionally, statistically significant positive correlations between seminal levels of Gal-1 and Gal-3 and free testosterone in healthy individuals were reported (r = 0.205, p = 0.053; r = 0.219, p = 0.038, respectively). On the other hand, there were negative correlations between serum and seminal levels of Gal-1 and Gal-3, total and progressive sperm motility, sperm count and abnormal sperm forms in healthy individuals (r = -0.382, p < 0.001; r = -0.405, p < 0.001; r = -0.376, p < 0.001; r = -0.364, p < 0.001) (r = -0.394, p < 0.001; r = -0.467, p < 0.001; r = -0.413, p < 0.001; r = -0.433, p < 0.001); (r = -0.372, p < 0.001; r = -0.377, p < 0.001; r = -0.317, p = 0.002; r = -0.311, p = 0.003)(r = -0.445, p < 0.001; r = -0.498, p < 0.001; r = -0.453, p < 0.001; r = -0.463, p < 0.001, respectively). Furthermore, statistically significant positive correlations between serum levels of Gal-1 and Gal-3 and age in azoospermic patients were reported (r = 0.511, p < 0.001; r = 0.390, p = 0.008, respectively). On the other hand, there were negative correlations between seminal Gal-1 and estradiol (E2) and seminal Gal-3 and FSH and LH in azoospermic patients (r= -0.318, p = 0.033; r = -0.322, p = 0.031; r = -0.477, p < 0.001, respectively). Also, negative correlations between serum Gal-3 and total and free testosterone in azoospermic patients were detected (r = -0.396, p = 0.007; r = -0.375, p = 0.011, respectively).

CONCLUSIONS

Elevated serum and seminal levels of Gal-1 and Gal-3 have detrimental effects on spermatogenesis. Furthermore, the current study demonstrated potential regulatory effects of reproductive hormones on Gal-1 and Gal-3. Thus, future studies are needed to confirm such findings.

The Novel Key Genes of Non-obstructive Azoospermia Affect Spermatogenesis: Transcriptomic Analysis Based on RNA-Seq and scRNA-Seq Data

Non-obstructive azoospermia (NOA) is one of the most important causes of male infertility. It is mainly characterized by the absence of sperm in semen repeatedly or the number of sperm is small and not fully developed. At present, its pathogenesis remains largely unknown. The goal of this study is to identify hub genes that might affect biomarkers related to spermatogenesis. Using the clinically significant transcriptome and single-cell sequencing data sets on the Gene Expression Omnibus (GEO) database, we identified candidate hub genes related to spermatogenesis. Based on them, we performed Gene Ontology (GO) functional enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment pathway analyses, protein-protein interaction (PPI) network analysis, principal component analysis (PCA), cell cluster analysis, and pseudo-chronological analysis. We identified a total of 430 differentially expressed genes, of which three have not been reported related to spermatogenesis (C22orf23, TSACC, and TTC25), and the expression of these three hub genes was different in each type of sperm cells. The results of the pseudo-chronological analysis of the three hub genes indicated that TTC25 was in a low expression state during the whole process of sperm development, while the expression of C22orf23 had two fluctuations in the differentiating spermatogonia and late primary spermatocyte stages, and TSACC showed an upward trend from the spermatogonial stem cell stage to the spermatogenesis stage. Our research found that the three hub genes were different in the trajectory of sperm development, indicating that they might play important roles in different sperm cells. This result is of great significance for revealing the pathogenic mechanism of NOA and further research.