Long-Term Effects of Neonatal LPS and Caspase -1 İnhibitor Administration on Gonadotropin Levels and Testicular Histology in Rats

Abstract

Aim: Endotoxins (lipopolysaccharides, LPS) negatively affect reproduction by decreasing gonadotropin levels in the acute period. The aim of this study is to investigate the long-term effects of re-injection of endotoxin in adulthood on gonadotropin release and testicular tissue in male rats injected with endotoxin with IL-1 beta inhibitor (Q-Vd-OPh; caspase-1 inhibitor, Cİ) in the neonatal period.
Material and Methods: On postnatal day 7, male rat pups were injected once with either Salin, LPS (50µg/kg), LPS (50µg/kg)+CI (1mg/kg). On postnatal 10 months, these rats were either injected with saline or LPS (50 µg/kg). 10 days after these injections, serum samples and testicular tissues were taken and the experiment was terminated.
Results: Respectively, control, Salin+LPS, LPS+Salin; LPS+LPS; LPS(CI)+Salin and LPS(CI)+LPS groups were 18.8±1.6; 11.3±1.2; 23.4±2.0; 22.2±1.2 ve 23.6±1.4 ng/ml for serum LH concentrations (p<0,05); while 33.4±2.5; 29.6±1.4; 32.1,6±2.0 28.7 0.8 and 35.5±3.3 ng/ml for FSH concentrations (p>0,05). Seminiferous tubule damage was observed in LPS groups (p<0,05).
Conclusion: This research demonstrates (1) neonatal LPS injections do not negatively affect gonadotropin release in the long term, (2) IL-1 β plays a critical role in the programming of reproduction, especially in terms of testicular histology.

Keywords

• neonatal LPS
• LH
• FSH
• seminiferous tubules
• caspase-1 inhibitor

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