Efecto de la Suplementación Dietética de Ácidos Grasos N-3 sobre la Expresión de los Genes Scd1, Scd5, Elongasa 5 Y Elongasa 6 en Individuos Obesos de 10 A 16 Años

Abstract

Obesity is a multifactorial disease with a rising incidence all over the world. It is associated with the development of metabolic diseases in adults and pediatric patients. The use of omega-3 fatty acids is an alternative for managing the metabolic alterations secondary to obesity and to modulate some lipogenic enzymatic pathways, such as desaturation and elongation. Enzymes as SCD1y Elovl6 have been implicated in the development of obesity, while SCD5 and Elovl5 have been associated with altered lipid metabolism in obesity. The aim of this study was to correlate the difference in gene expression with biochemical and anthropometric variables in a population of teenage (10 to 16 yrs. old) obese individuals after supplementation with 3000mg of omega 3 fatty acids for 12 weeks. We studied 18 patients with informed consent. A biopsy of subcutaneous adipose tissue was taken. We also obtained peripheral blood to determine gene expression, blood glucose and lipid profile. Additional data collected: Anthropometric variables (weight, height, BMI, waist circumference andhip percentages of lean and fat mass). Gene expression was determined after extractionof RNA, cDNA retroconversion and PCR-RT amplification and specific primers and fluorescent probes. There was a significant difference in the expression of Elovl5 in adipose tissue (p = 0.009) and SCD1 in blood mononuclear cells (p = 0.004).Triglycerides decreased (p = 0.002) with no associated change in gene expression.Elovl5 expression in adipose tissue was associated with HDL cholesterol (r = 0.802, p = 0.017), total cholesterol change (r = 0.786, p = 0.021), and Elovl5 expression in mononuclear cells was associated to waist circumference (r =- 0.699, p = 0.024) and hip circumference (r =-0.685, p = 0.029). We found a coordinated regulation of SCD1 and SCD5 in mononuclear cells. There was a trend toward increased LDL cholesterol (p> 0.05). As reported by other Gunnarsdottir et al in 2004, it is necessary to carefully assess the levels of LDL in patients undergoing supplementation with omega-3 fatty acids. Finally we found that omega-3 fatty acids reduce triglycerides in teenage obese patients and Elovl5 regulation in adipose tissue is related to total cholesterol and HDL cholesterol, which puts the Elovl5 as a potential therapeutic target in the treatment of lipid disorders.