Kisspeptin participation in deleterious ghrelin effects on spermatogenesis

MARIA BELEN PORETTI; BIANCONI SANCIAGO; MAESTRI GIULIA; ANA CAROLINA MARTINI; LAURA VICENTI; MARTA FIOL DE CUNEO; HELGI B. SCHIOTH; VALERIA PAOLA CARLINI

Congreso; Reunión Conjunta 2016 entre la Sociedad Argentina de Investigación Clínica (SAIC), la Sociedad Argentina de Inmunología (SAI) y la Sociedad Argentina de Farmacología Experimental (SAFE); 2016

Sociedad Argentina de Investigación Clínica (SAIC), la Sociedad Argentina de Inmunología (SAI) y Sociedad Argentina de Farmacología Experimental (SAFE)

Physiological mechanisms that control energy balance are reciprocally related to those that control reproductive function. In previous work we have shown that chronic intrahypothalamic ghrelin (Ghr) administration (42 days), an orexigenic peptide of 28 amino acids, decreases epididymal sperm concentration and motility in mice, these results correlate with a reduction in plasma testosterone concentration.In this study, we investigated the involvement of kisspeptin (Kiss-1) system and its receptor (GPR54) in deleterious effects on spermatogenesis after chronic Ghr central administration. Albino Swiss adult male mice were implanted with osmotic pumps (Alzet) Model 1007D (0.5 l / hour-7 days) or model 2006 (0.15 l / hour-42 days) on hypothalamus and infused with sterile cerebrospinal fluid (CSF-control) or different Ghr doses (0.3 or 3.0 nmol / ul). Animals were sacrificed and the hypothalamus dissected to assess the expression of genes encoding gonadotropin releasing hormone (GnRH), Ghr receptor (GHRS), Kiss-1 and GPR54 by real time PCR.Results show a significant decrease of relative Kiss-1 expression (F = 10.25, p ≤ 0.05) and its receptor GPR54 (F = 11.34, p ≤ 0.05) in animals treated per 7 days with Ghr 3,0 nmol/ul, this decrease was also shown in animals treated for 42 days (Kiss-1 expression: F = 9,40, p≤ 0.05; GPR54 expression : F = 9.03; p ≤ 0.05). No significant differences were found in GHRS or GnRH expression (p> 0.05).This paper provides new evidence about possible mediators involved in Ghr deleterious effect on male reproductive system, indicating that this peptide induces a negative modulation at central level on the expression of Kiss-1 and / or its receptor.