Inhibin B Levels in Relation to Obesity Measures and Lipids in Males with Different Numbers of Metabolic Syndrome Components
D. O. Laniyan
Department of Chemical Pathology, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
M. A. Charles-Davies *
Department of Chemical Pathology, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
A. A. Fasanmade
Department of Medicine, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
J. A. Olaniyi
Department of Haematology, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
O. E. Oyewole
Department of Health Promotion and Education, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
M. O. Owolabi
Department of Medicine, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
J. R. Adebusuyi
Department of Medical Social Services, University College Hospital, Ibadan 200212, Nigeria.
O. Hassan
Department of Medical Social Services, University College Hospital, Ibadan 200212, Nigeria.
B. M. Ajobo
Department of Dietetics, University College Hospital, Ibadan 200212, Nigeria.
M. O. Ebesunun
Department of Chemical Pathology, College of Health Sciences, Olabisi Onabanjo University, Ago-Iwoye 120005, Nigeria.
K. Adigun
General out Patient Unit, University College Hospital, Ibadan 200212, Nigeria.
K. S. Akinlade
Department of Chemical Pathology, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
S. U. Okoli
Department of Chemical Pathology, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
O. G. Arinola
Department of Chemical Pathology, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
E. O. Agbedana
Department of Chemical Pathology, College of Medicine, University of Ibadan, Ibadan 200284, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Introduction: Defective spermatogenesis and metabolic syndrome affect 2-4% and 12.4% of males respectively. Deficient testosterone levels due to increased conversion of testosterone to oestradiol have been demonstrated in males with the metabolic syndrome (MS) with limited pituitary and leptin contribution. Defective spermatogenesis is thus implicated in males with MS but is controversial. Inhibin B is a marker of spermatogenesis. This study aims at evaluating inhibin B levels and their relationship with obesity measures and lipids in males with different number of MS components.
Materials and Methods: This is a preliminary prospective study in which a total of 106 apparently healthy males (30, 30, 30 and 16 males with 0, 1, 2 and ≥3 components of metabolic syndrome (NMSC) respectively) aged 19-64 years were purposely selected. Blood pressure (BP) and obesity measures (including visceral adiposity index (VAI) and body mass index (BMI)) were obtained by standard methods. Fasting plasma glucose (FPG), total cholesterol (TC), triglycerides and high density lipoprotein cholesterol (HDLC) were determined by enzymatic methods while low density lipoprotein cholesterol (LDLC) and the lipid ratios (TG/HDLC, TC/HDLC, LDLC/HDLC) were calculated. Inhibin B was analysed by enzyme linked immunosorbent assay (RayBiotech, Inc. USA). Data analysed using analysis of variance (ANOVA) and multiple regressions were significant at P <.05.
Results: Inhibin B decreased significantly in males with 0 to 2 NMSC (P <.05). However, inhibin levels between males with 0 and ≥3 NMSC were similar. Age and inhibin B levels were also similar among the different classes of BMI (P>0.05). Inhibin B related positively with HDLC and TC but negatively with VAI, LDLC and TC/HDLC.
Conclusion: Reproductive function appears protected in Nigerian males with MS. However, improvement in HDLC, LDLC, TC levels, VAI and TC/HDLC may enhance fertility potential especially in males with one or two MS components, probably through dietary modulation and physical activity.
Keywords: Metabolic syndrome, hormones, inhibins, hypogonadism, obesity.