Abstract
Background: Conjugated Linoleic Acid [CLA] is suggested as a novel drug to improve obesity.
Objectives: The aim of this study was to elucidate the possible role of CLA in ameliorating the pathophysiology in obese rats and modulate its immune function.
Methods: Forty adult male albino rats of local strain, weighing [120-160] grams each, were used. Rats were ran-domly divided into five equal experimental groups, control, CLA-supplemented, obese, CLA-prophylactic obese and CLA-treated obese groups obesity was induced by High Fat Diet [HFD] for 12 weeks. CLA was administered orally in a dose of 1500mg/kg body weight for 12 weeks. Initial and final Body Weight (BW) and Body Mass Index (BMI) and food intake were measured. Total Leucocytic Count (TLC) and its differential count and serum Tumor Necrosis Factor-alpha (TNF-a) were measured. Visceral fat and total white abdominal fat to each 100 [gm]/BW were measured. Caspase 3 expression was evaluated in the abdominal fat biopsies using immuno-histochemistry.
Results: High fat diet resulted in deterioration and impair-ment of most measured parameters. CLA supplementation decreased final BW of obese rats, food intake, visceral fat, and total abdominal together with increased CD8+, CD4+ T lymphocytes and eosinophilic %. Moreover, CLA supplemen-tation decreased TNF-a  in CLA-supplemented and CLA-prophylactic groups but not in CLA-treated group. High fat diet increased TLC and CD4+ T lymphocytes but decrease eosinophilic % and CD8+ T lymphocytes. In addition, CLA increased the positivity of caspase 3 in CLA-prophylactics and CLA-treated obese groups.
Conclusion: CLA supplementation, either as a prophylactic agent or a therapeutic one, to the high fat feed rats could ameliorate most of the detrimental effects of obesity, particu-larly those related to the immune system. This beneficial effect of CLA could be explained by its immune modulator, anti-inflammatory and pro apoptotic effects.