Association of leptin levels with obesity and blood pressure: possible common genetic variation

Abstract

OBJECTIVE: To ascertain the extent to which relationships between obesity (OB) and blood pressure (BP) can be explained by an individual's leptin plasma levels. DESIGN: Pedigree-based cross-sectional study in an apparently healthy population of European origin. SUBJECTS: The study sample is comprised of 90 nuclear and more complex families totaling 210 male and 213 female subjects aged 18-75 y, randomly recruited in Bashkorstan Autonomic region, Russia. MEASUREMENTS: Various fatness and fat distribution traits (including nine circumferences (CRCs), and eight skinfolds (CKFs) by anthropometry), blood pressure, and plasma leptin levels (by ELISA kits). RESULTS: Adjustment for circulating leptin led to attenuation of the magnitude of correlations between OB and BP, regardless of trait pair and sex cohort. Some of these correlations became statistically nonsignificant. All familial effects were gone, and heritability estimates became virtually zero after adjustment of each of the OB traits and systolic blood pressure (SBP) in offspring for leptin values in parents. CONCLUSION: BP and OB covariation is substantially mediated by circulating leptin levels. As a result, body fat has only a weak independent effect on BP variation after adjustment for leptin levels. Our findings also strongly suggest that genetic variation in body mass index, SKFs, and even body CRCs, as well as of SBP is due to genetic variation of leptin. Genetic variation of diastolic blood pressure in the present sample, however, shared very little with that of leptin.

Genetic and environmental influences on body fat and blood pressure in African-American adult twins

“…There also may be common effects not accounted for by shared genes, such as insulin affecting sympathetic activity and thus Genetic influences on body fat and blood pressure TL Nelson et al increasing blood pressure. 37 A recent study by Livshits 38 found among families that correlations between blood pressure and obesity were mediated by leptin. They also found that the familial effects on body fat and blood pressure were totally gone after controlling for leptin, suggesting that genetic variation in body fat and blood pressure is due to genetic variation of leptin.…”

Effects of Resistance Exercises on Serum Leptin and Some Inflammatory Markers in Obese Males

“…Acute, resistance exercise has been reported to have no impact (Livshits et al, 2005;Fenkci et al, 2006;Konstantinides et al, 2001;Franklin, 2005;Rahmouni et al, 2004;Altman, 2003) or to decrease plasma leptin levels in these studies (Mendosa-Nunez et al, 2002). After 20 weeks of training a decrease in leptin levels was observed in men, but only if decreases in body fat occurred (Franklin, 2005).…”

“…It also suppresses appetite through acting on the hypothalamus (Mokdad et al, 2003;Ronti et al, 2006;MendosaNunez et al, 2002). In recent years, leptin has been reported to increase arterial pressure and heart rate by peripherally or centrally mediated mechanisms (Livshits et al, 2005;Franklin 2005;Rahmouni and Haynes 2004). The finding that leptin is linked to heart-disease risk independently from C-reactive protein (CRP), an inflammation marker, strongly suggests that fat may be important in heart-disease risk (Altman 2003;Canavan et al, 2005).…”

“…Leptin has been demonstrated to induce insulin resistance (Houmard et al, 2000). Leptin is involved in the pathogenesis of vascular disease and may represent a link between obesity, diabetes, inflammation and atherosclerosis (Krauss et al, 1998;Livshits et al, 2005). Leptin increases energy expenditure by enhancing sympathic nervous activity and lipolysis (Kraemer et al, 2002;Fenkci et al, 2006;Konstantinides et al, 2001).…”

The Taipei Adolescent Twin/Sibling Family Study II: Depression, Insulin Resistance, and Hormonal Factors

“…A recent review concluded the existence of an association between depression and type 2 diabetes (Musselman et al, 2003). Furthermore, it has been shown that several hormones such as cortisol, an index of hypothalamic-pituitary-adrenal (HPA) axis activity and leptin, an adiposity hormone involved in food intake and weight regulation, have been involved in the regulation of mood and metabolic function (Atmaca et al, 2005;Bjorntorp, 2001;Kraus et al, 2001;Liuzzi et al, 1999;Livshits et al, 2005). Despite the consistent overlap between these two traits, few studies have adopted an integrative strategy that includes both psychological and physiological assessments to elucidate the etiology of anxiety/depression and metabolic functions.…”