Interleukin-8 as a potential cytokine marker in male infertility

La interleucina-8 como posible marcador citocínico en la infertilidad masculina

Background: Infertility is defined by the World Health Organization (WHO) as the absence of pregnancy after 12 months or more of regular unprotected sexual activity. Male factors contribute to nearly half of infertility cases, with inflammatory conditions of the male reproductive tract playing a significant role. This study aimed to evaluate interleukin-8 (IL-8) levels in seminal plasma and their association with semen parameters in men with chronic abacterial prostatitis/chronic pelvic pain syndrome (CAP/CPPS). Methods: A total of 124 infertile men with CAP/CPPS and 20 healthy fertile controls were included in the study. IL-8 levels in serum and seminal plasma were measured using enzyme-linked immunosorbent assay (ELISA). Semen analysis was performed according to WHO guidelines (1999, 2010). Correlation analysis was conducted to assess the relationships between IL-8 levels and semen parameters. Results: IL-8 levels were significantly higher in infertile patients compared with controls, both in serum (9.4 ± 5.6 vs. 0.75 ± 0.11 pg/mL; p < 0.01) and seminal plasma (283.6 ± 13.1 vs. 82.6 ± 35.0 pg/mL; p < 0.01). Seminal IL-8 showed significant negative correlations with sperm concentration, motility, and fertility indices (p < 0.05 to p < 0.001). No significant differences in IL-8 levels were observed between CAP/CPPS categories IIIA and IIIB. Conclusions: Elevated IL-8 levels are associated with impaired semen quality in men with CAP/CPPS. Seminal IL-8, in particular, may serve as a sensitive biomarker of local immune activation in the male reproductive tract. Further studies are required to determine its diagnostic accuracy and clinical applicability.

Resumen
Antecedentes: La infertilidad se define por la Organización Mundial de la Salud (OMS) como la ausencia de embarazo tras 12 meses o más de relaciones sexuales regulares sin protección. Los factores masculinos contribuyen aproximadamente a la mitad de los casos de infertilidad, y las afecciones inflamatorias del tracto reproductor masculino desempeñan un papel importante. El presente estudio tuvo como objetivo evaluar el nivel de interleucina-8 (IL-8) en el plasma seminal y su asociación con los parámetros seminales en hombres con prostatitis crónica abacteriana/síndrome de dolor pélvico crónico (CAP/CPPS). Métodos: Se incluyeron un total de 124 hombres infértiles con CAP/CPPS y 20 controles fértiles sanos. Los niveles de IL-8 en suero y plasma seminal se determinaron mediante ensayo inmunoenzimático (ELISA). El análisis seminal se realizó de acuerdo con los criterios de la OMS (1999, 2010). Resultados: Los niveles de IL-8 fueron significativamente más altos en los pacientes infértiles en comparación con los controles, tanto en suero (9.4 ± 5.6 frente a 0.75 ± 0.11 pg/mL; p < 0.01) como en plasma seminal (283.6 ± 13.1 frente a 82.6 ± 35.0 pg/mL; p < 0.01). La IL-8 seminal mostró correlaciones negativas significativas con la concentración espermática, la motilidad y los índices de fertilidad (p < 0.05 to p < 0.001). No se observaron diferencias significativas en los niveles de IL-8 entre las categorías IIIA y IIIB de CAP/CPPS. Conclusiones: Estos hallazgos indican que niveles elevados de IL-8 se asocian con una peor calidad seminal en hombres con CAP/CPPS. La IL-8 puede considerarse un posible biomarcador que refleja la activación inmune local en el tracto reproductor masculino. Sin embargo, se requieren estudios adicionales para evaluar su rendimiento diagnóstico y su aplicabilidad clínica.

Male infertility; Cytokines; Interleukin-8; Chronic abacterial prostatitis

Palabras Clave
Infertilidad masculina; Citocinas; Interleucina-8; Prostatitis crónica abacteriana

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