Updating the effects of fatty acids on skeletal muscle Best free private cam2cam
In this context, the present study was undertaken to determine whether raising plasma FFA does induce an increase in expression of FAO enzymes in skeletal muscle and, if it does, to obtain evidence regarding whether the increase in FFA activates PPARδ.A second aim, if raising FFA was found to increase FAO enzymes, was to determine whether an isolated increase in FAO enzymes results in an increase in the capacity to oxidize fatty acids or whether the citrate cycle and respiratory chain are rate-limiting.The COX1 and cytochrome b genes are in the mitochondrial genome, and the 18S gene is in the nuclear genome.Values are means ± SE for four rats with ↑FFA and five controls.1) and UCP3, which are encoded in PPARδ target genes, suggested that the increase in FFA resulted in activation of PPARδ.
The PPARs are activated by long-chain fatty acids (14, 15).
Plasma FFA were markedly elevated in the rats fed the high-fat diet and given heparin (2.06 ± 0.42 m M; range 1.22–3.84 m M) for six rats given heparin compared with 0.25 ± 0.02 m M for six chow-fed rats. 1 , protein levels of three enzymes used as markers for the mitochondrial FAO pathway.
Medium-chain acyl-Co A dehydrogenase, long-chain acyl-Co A dehydrogenase, and very long-chain acyl-Co A dehydrogenase were all significantly increased in epitrochlearis muscles of rats in which plasma FFA were raised daily for 4 weeks.
m CPT type 1 (m CPT1) m RNA was also significantly increased in triceps muscles in response to elevation of plasma FFA (Fig. The genes that encode these FAO enzymes are regulated by PPARδ and PPARα (8, 9, 11, 18).
Expression of the uncoupling proteins is also regulated by these nuclear receptors (9, 11, 19), and uncoupling protein 3 (UCP3) expression was increased in muscle of rats in which plasma FFA were raised (chow group 1.0 ± 0.16 vs.