Gender Difference in Proteome of Brown Adipose Tissues between Male and Female Rats Exposed to a High Fat Diet

Abstract

Background: Although the importance of gender as a key determinant in health and illness has been recognized for a long time, systematic studies of gender differences in medicine are still lacking. We hypothesized that interscapular brown adipocyte tissue (BAT), is not only a key tissue contributing to energy expenditure, but also regulates diet-induced thermogenesis, and may be an ideal target for studying gender differences in obesity development in response to a high fat diet (HFD). Methods: We therefore performed differential proteome analysis of BAT from lean and obese rats of both genders fed a HFD using 2-DE combined with MALDI-TOF-MS. Results: When exposed to a HFD, male rats gained more body weight with increased values of plasma biochemical parameters than did female rats. Among 595 matched spots, 48 differentially expressed identified spots showed significant gender differences, whereas 7 proteins showed no gender differences, but did show a HFD response. Conclusions: Proteomic investigations into gender-dimorphic protein modulation in BAT may provide conclusive results showing higher expression of numerous proteins involved in thermogenesis and fat oxidation as well as lower expression of proteins contributing to fat synthesis in female rats than in male rats.

Differential Protein Expression in White Adipose Tissue from Obesity-Prone and Obesity-Resistant Mice in Response to High Fat Diet and Anti-Obesity Herbal Medicines

“…2), protein spots were identified by MALDI-TOF-MS (Table 3), and database searches were performed with high confidence based on high score and sequence coverage. For the results, a total of 1,045 individual matched spots ranging in mass from 6 to 240 kDa between pH 3-10 were detected, and obtained WAT protein maps represented patterns that were similar to our previous results [26,27,28,34]. Fifty-nine spots were identified with statistically different intensities between the ND and OP groups.…”

“…2-DE experiments were conducted using the previous methods outlined by our laboratory [26,27,34]. Briefly, immobilized pH gradient (IPG)-isoelectric focusing (IEF) of WAT samples was performed on pH 3-10 and 18 cm IPG DryStrips (GE Healthcare, Buckinghamshire, UK) in a PROTEIN IEF cell (Bio-Rad) using the protocol recommended by the manufacturer.…”

“…Separation, identification, and characterization of proteins as well as their interactions with other proteins are the essential goals of proteomic analysis. Two-dimensional electrophoresis (2-DE) coupled with MALDI-TOF-MS is considered a powerful tool for the separation of thousands of adipose tissue proteins [26,27]. This approach enables comparison between normal and disease samples revealing differentially expressed proteins.…”

Lecithin:Cholesterol Acyltransferase Deficiency Protects against Cholesterol-induced Hepatic Endoplasmic Reticulum Stress in Mice

“…However, a recent study by De Marinis et al (39) identified a strong gender-dependent effect in the regulation of hepatic cholesterol through modulation of the INSIG1/ SCAP/SREBP machinery, providing a plausible mechanism to account for, at least in part, the gender effect of the observed metabolic phenotypes in our models. Other tissues that may contribute to the observed gender dimorphism include brown adipose tissue (40).…”

Role of sex hormones in modulation of brown adipose tissue activity

“…An augmented thermogenic activity, driven by the increased mitochondrial function of female BAT, may underlie the different body weight gain that female rodents exhibit following a high-fat diet (HFD) in comparison with males. Indeed, it has been shown that when exposed to a HFD, male rats gain more body weight than females, and this phenotype is paralleled in BAT with a lower expression of numerous proteins involved in thermogenesis and fat oxidation, as well as a higher expression of proteins contributing to fat synthesis (Choi et al 2011).…”