TITLE:
Apelin and Testosterone Levels in Men with Metabolic Syndrome
AUTHORS:
Petya Angelova, Zdravko Kamenov, Adelina Tsakova
KEYWORDS:
LOH; Metabolic Syndrome; Diabetes Mellitus; Apelin; Testosterone
JOURNAL NAME:
Open Journal of Endocrine and Metabolic Diseases,
Vol.4 No.2,
February
18,
2014
ABSTRACT:
Apelin is a new
adipokine associated with obesity. Data about the relationship of apelin to the
metabolic syndrome (MS) are still scarce. Late-onset hypogonadism (LOH) is
common in men with MS, but we did not find data about the levels of apelin in
men with LOH. The aim of this study is to determine the levels of apelin in men
with MS with or without LOH. Patients and Methods: 99 men are included in the
study. Of them 65 have MS (IDF 2005) and they are divided according to their
morning total testosterone (TT) level (cutoff 10.4 nmol/l) into two groups: MS-low T (N = 21) and
MS-normal T (N = 44). The control group consists of 34 men without MS and with normal T. Apelin is
determined in serum using enzyme linked
immunosorbent assay.
Some of the men were additionally assigned to testosterone treatment and
monitored. Results: MS
men are at mean age (±SD) = 50.4 ± 9.6 years and TT = 13.6 ± 5.4 nmol/l. The control group is
at age = 51.5 ± 6.4 years (NS)
and TT = 17.9 ± 5.6 nmol/l (p 0.001). The levels of apelin are
higher in the MS group—1.61 ± 0.53 ng/ml
compared to the control one—1.38 ± 0.57 ng/ml (p 0.05). There is no difference
between MS-lowT—1.53 ± 0.52 ng/ml and MS-normal T —1.65 ± 0.53 ng/ml sub-groups. The
MS-normal T differs from
the control group (p 0.05). Significant correlation of
testosterone with apelin levels is not found. Although apelin correlates with
other laboratory parameters: LDL-levels in the MS-patients (Pearson’s = 0.311, p 0.05); HbA1c in men with T2DM
(Pearson’s = 0.285, p 0.05); serum creatinine levels
(Pearson’s = 0.257, p 0.001). The patients that are
assigned to testosterone substitution show a trend for lowering apelin levels. Conclusions: In this study, higher apelin levels are found in
the presence of MS compared to healthy men, but do not differ between men
having MS with low or normal T.