Topographical Body Fat Distribution Links to Amino Acid and Lipid Metabolism in Healthy Non-Obese Women

Abstract

Visceral adiposity is increasingly recognized as a key condition for the development of obesity related disorders, with the ratio between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) reported as the best correlate of cardiometabolic risk. In this study, using a cohort of 40 obese females (age: 25–45 y, BMI: 28–40 kg/m2) under healthy clinical conditions and monitored over a 2 weeks period we examined the relationships between different body composition parameters, estimates of visceral adiposity and blood/urine metabolic profiles. Metabonomics and lipidomics analysis of blood plasma and urine were employed in combination with in vivo quantitation of body composition and abdominal fat distribution using iDXA and computerized tomography. Of the various visceral fat estimates, VAT/SAT and VAT/total abdominal fat ratios exhibited significant associations with regio-specific body lean and fat composition. The integration of these visceral fat estimates with metabolic profiles of blood and urine described a distinct amino acid, diacyl and ether phospholipid phenotype in women with higher visceral fat. Metabolites important in predicting visceral fat adiposity as assessed by Random forest analysis highlighted 7 most robust markers, including tyrosine, glutamine, PC-O 44∶6, PC-O 44∶4, PC-O 42∶4, PC-O 40∶4, and PC-O 40∶3 lipid species. Unexpectedly, the visceral fat associated inflammatory profiles were shown to be highly influenced by inter-days and between-subject variations. Nevertheless, the visceral fat associated amino acid and lipid signature is proposed to be further validated for future patient stratification and cardiometabolic health diagnostics.

The influence of a 3-week body mass reduction program on the metabolic parameters and free amino acid profiles in adult Polish people with obesity

“…25,26 The increased plasma BCAA concentration may be the result of the impaired BCAA-catabolizing capacity of the adipose tissue, an improper high-fat and highprotein diet (dietary protein comprised of >20% BCAA) and increased catabolic pathways of BCAAs. 13,20,27,28 So far, only a few studies rated the changes in the BCAA levels after weight loss through diet and physical activity, but those studies were conducted on different populations (especially Caucasian and Japanese subjects) and used another model of body mass reduction program (based on nutritional recommendation and lifestyle intervention, but not a strictly composed diet). A 7-year prospective KORA study on a group of Caucasian patients with obesity showed a significant correlation between the average percentage increase in body weight and the increase in the BCAA, phenylalanine, tyrosine, and glutamate levels.…”

“…12 Moreover, Yamakado et al hypothesized that the amount of visceral fat changes AA profile, and that the multivariate logistic regression model of free AAs in plasma can discern non-apparent visceral obesity in adult Asian individuals. 12 The associations between the BCAA levels and tyrosine with visceral adiposity -irrespective of ethnicity, lifestyle or environmental conditions -were also studied by Marti et al 13 Despite the great interest in and development of the state of knowledge about metabolic profiles in people with obesity, the perturbations in AA concentrations in the serum of adult patients suffering from obesity after weight loss are not fully understood. The previous studies in this area focused on describing the changes in metabolic profile after weight loss achieved by bariatric surgery or longterm body mass reduction programs based on lifestyle intervention.…”

The Omics of Obesity

“…Germ-free mice have less body fat than regularly raised mice despite the fact they actually eat more and take in more calories which should oppose this affect [59]. Further studies in germ-free mice have demonstrated that an obese phenotype is transmissible from mouse to mouse via the gut microbiota.…”

Lipidomics

“…[33][34][35][36][37][38][39][40] A summary of the studies is presented in Table 3. Lipid profiling has shown promising results in diabetes mellitus, [41][42][43][44][45][46][47] CVDs, 35,37,38,48-52 metabolic disorders, 40,53,54 dietary habits, and obesity, 47,49,[55][56][57][58][59][60][61] as well as in determining response to drug therapy. [62][63][64][65] Most studies analyzed either blood or tissue samples (ie, diabetic retinopathy, 46 atherosclerotic plaques, 52 muscle, 47 or adipose tissue).…”

“…ELISAs have been used for detection of oxidized lipoproteins 34,35 and NMR for profiling of lipoprotein subclasses. 48,55,61 In a family cohort study exploring the relation of circulating lipids to longevity, a sex-specific lipid signature was associated with familial longevity in women, whereas no significant differences were observed in men. 33 Female middle-aged offsprings of nonagenarians (between 90 and 100 years old) showed a higher ratio of monounsaturated instead of polyunsaturated lipid species and thus the authors suggest that the female plasma lipidome is less prone for oxidative stress.…”