Seminal-Plasma Kisspeptin and the Seminal/Serum Kisspeptin Ratio in Relation to Sperm Motility, Morphology and Oxidative Stress in Infertile Iraqi Men

Durar Kamil Jabbar

doi:10.37022/wjcmpr.v8i2.441

Authors

Durar Kamil Jabbar Department of Basic Sciences, College of Dentistry, University of Al-Qadisiyah, Al-Diwaniyah, Iraq.

Abstract

Kisspeptin regulates the reproductive axis centrally, but it is also present in seminal plasma, where its meaning is unclear. We compared the two compartments and asked whether their ratio tracks semen quality better than either value alone. One hundred and fifty men were studied: 40 fertile controls, 40 asthenozoospermic, 30 teratozoospermic and 40 with oligoasthenoteratozoospermia (OAT). Semen was assessed by WHO 2021 criteria. Kisspeptin was measured in serum and seminal plasma by ELISA, and seminal malondialdehyde (MDA), total antioxidant capacity (TAC), total oxidant capacity (TOC), superoxide dismutase, glutathione and the oxidative stress index (OSI) were measured in the same samples. Seminal kisspeptin fell stepwise, from 136.64 ± 32.67 pg/mL in controls to 56.88 ± 17.17 pg/mL in OAT (F = 76.59, P < 0.001), while serum kisspeptin moved the other way (81.53 ± 20.95 to 109.09 ± 29.36 pg/mL, P < 0.001). The seminal/serum ratio followed the same gradient, falling from 1.79 ± 0.60 to 0.56 ± 0.26. Seminal kisspeptin correlated positively with total motility (r = 0.725) and normal morphology (r = 0.643), and negatively with MDA (r = −0.670) and OSI (r = −0.604); all P < 0.001. By ROC analysis it separated infertile from fertile men with an AUC of 0.941 (95% CI 0.902–0.981) at a cut-off of 99.4 pg/mL, and the ratio gave 0.935 at a cut-off of 1.24. Serum kisspeptin reached only 0.732. Seminal kisspeptin, taken directly or as a ratio, appears to be a redox-linked marker of sperm function.

Keywords:

Kisspeptin, seminal plasma, oxidative stress index, sperm motility, sperm morphology, male infertility, Iraq

DOI

https://doi.org/10.37022/wjcmpr.v8i2.441

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