Serum leptin levels in Ache Amerindian females with normal adiposity are not significantly different from American anorexia nervosa patients

Abstract

Serum leptin, a polypeptide hormone secreted primarily by adipocytes, is a reflection of somatic fat availability in humans and other vertebrates. Among Ache Amerindians, leptin levels are very low in contrast to other populations, despite comparable adiposity with individuals exhibiting much higher leptin levels. In order to gain a greater understanding of these differences, leptin levels were compared between Ache Amerindian females (n = 12, mean age = 32.2 +/- 14.0 SD), American females diagnosed with anorexia nervosa (n = 22, mean age = 23.0 +/- 4.0), and non-anorectic American controls (n = 23, mean age = 23.0 +/- 4.0). Ache leptin (5.6 +/- 3.2 ng/ml) was not significantly different from anorectic patients (5.6 +/- 3.7 ng/ml; P > 0.98) despite greater adiposity (Ache 33.3% +/- 4.4% vs. anorectic 7.0% +/- 2.0%; P < 0.0001). Ache adiposity was also higher than American controls (leptin 19.1 +/- 8.1 ng/ml; fat 28% +/- 5.0%; P < 0.004) underscoring the uniqueness of Ache leptin profiles. This suggests a greater range of population variation in leptin physiology than previously suspected and intimates the potential role of chronic environmental conditions.

Leptin in a lean population of Filipino adolescents

“…In a recent study of adolescents in Korea, mean male and female leptin levels were six and four times higher, respectively, than their Cebu counterparts (Park et al, 2004). Although the Cebu findings were similar to the few subsistence-level populations for which data are available (Zimmet et al, 1998;Bribiescas, 2001Bribiescas, , 2005Iputo et al, 2001;Moore et al, 2004), the leptin values documented here stand out as among the lowest ever recorded in a healthy sample, and help illustrate the great range of leptin variability across human populations.…”

“…The vast majority of leptin research has focused on clinical samples with relatively high levels of adiposity and high body mass indices (BMI), and these studies consistently report strong correlations between adiposity and circulating leptin (Jequier, 2002). In contrast, circulating leptin is only weakly correlated, or not correlated at all, with adiposity in some lean human populations, or among wild primates with chronically low energy sufficiency or body mass (Banks et al, 2001;Bribiescas, 2001Bribiescas, , 2005Moore et al, 2002;Lindegä rde et al, 2004). Under the assumption that an abundance of body fat is an evolutionarily-novel condition, these differences in the relationship between adiposity and leptin in lean populations raise additional questions about the hormone's role as a signal of energy status (Banks et al, 2001;Collinson et al, 2005).…”

Active ghrelin levels across time and associations with leptin and anthropometrics in healthy ache Amerindian women of Paraguay

“…Post hoc comparisons with mean values from other active ghrelin measurements reported in the literature (Nakai et al, 2003) suggest no significant differences compared to healthy control subjects (P < 0.33) but were significantly lower than anorectic patients (P < 0.03), implying that active ghrelin levels among the Ache do not exhibit similar population differences as observed with leptin (Bribiescas, 2001(Bribiescas, , 2005Bribiescas and Hickey, 2006). However, formal comparisons with proper controls are needed.…”

The role of leptin in anorexia nervosa: clinical implications

“…47 Adult Ache Ameridians females with a mean BMI of 25.271.9 kg/m 2 (but nevertheless a low fat mass) had a mean leptin level of 5.673.2 mg/ml; 48 owing to a comparison with leptin levels of AN patients investigated by Grinspoon et al, 28 it was concluded that the levels of the Ameridians are within the anorectic range. 48 However, leptin levels of the Grinspoon et al study 28 are the highest reported in acute AN, potentially suggesting that the respective patients had already gained weight before blood sampling. Role of leptin in anorexia nervosa J Hebebrand et al…”