Cholesterol Intake and Atorvastatin Modulate SCD1 and ELOVL6 in Rat Retroperitoneal Adipose Tissue

Background

Stearoyl-CoA desaturase 1 (SCD1) and elongase 6 (ELOVL6) are key enzymes in the synthesis of monounsaturated fatty acids (MUFA). Gene expression for SCD1 and ELOVL6 is high in the white adipose tissue (WAT) and is regulated at the transcriptional level by various factors.

Objectives

This study aimed to assess the effect of (a) cholesterol-enriched diet and (b) atorvastatin in a hypercholesterolemic state, on the relative mRNA and protein levels and indices for SCD1 and ELOVL6 in rat retroperitoneal WAT (rWAT).

Methods

The mRNA and protein levels of SCD1 and ELOVL6 were determined using the RT-qPCR and Western blot techniques, respectively. Gas chromatography was used to determine the FA composition, and the SCD1 and ELOVL6 indices were then calculated.

Results

In the HC group, the content of SAT decreased, as did the percentage of 14:0, 16:0, and 18:0. Conversely, PUFA content increased, as did the percentage of 18:2 n-6 and the indices for SCD18 and FA elongation compared to the CT group. In the AT group, the mRNA and protein levels of SCD1 increased, whereas the MUFA content and the percentage of 18:1 n-9 decreased compared to the HC group.

Conclusion

The study showed that a cholesterol-enriched diet increased the SCD1 index, leading to a decrease in SAT as these were used for MUFA synthesis. In contrast, atorvastatin lowered MUFA content, suggesting a protective effect of this compound in the rWAT of hypercholesterolemic rats. Furthermore, atorvastatin increased the expression of SCD1 mRNA and protein but did not affect the SCD1 index.