Effects of Conjugated Linoleic Acid Associated With Endurance Exercise on Muscle Fibres and Peroxisome Proliferator‐Activated Receptor γ Coactivator 1 α Isoforms

Abstract

Conjugated linoleic acid (CLA) has been reported to improve muscle hypertrophy, steroidogenesis, physical activity, and endurance capacity in mice, although the molecular mechanisms of its actions are not completely understood. The aim of the present study was to identify whether CLA alters the expression of any of the peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α) isoforms, and to evaluate the possible existence of fibre-type-specific hypertrophy in the gastrocnemius and plantaris muscles. Mice were randomly assigned to one of four groups: placebo sedentary, CLA sedentary, placebo trained, or CLA trained. The CLA groups were gavaged with 35 μl per day of Tonalin® FFA 80 food supplement containing CLA throughout the 6-week experimental period, whereas the placebo groups were gavaged with 35 μl sunflower oil each day. Each administered dose of CLA corresponded to approximately 0.7 g/kg or 0.5%, of the dietary daily intake. Trained groups ran 5 days per week on a Rota-Rod for 6 weeks at increasing speeds and durations. Mice were sacrificed by cervical dislocation and hind limb posterior muscle groups were dissected and used for histological and molecular analyses. Endurance training stimulated mitochondrial biogenesis by PGC1α isoforms (tot, α1, α2, and α3) but CLA supplementation did not stimulate PGC1α isoforms or mitochondrial biogenesis in trained or sedentary mice. In the plantaris muscle, CLA supplementation induced a fibre-type-specific hypertrophy of type IIx muscle fibres, which was associated with increased capillary density and was different from the fibre-type-specific hypertrophy induced by endurance exercise (of types I and IIb muscle fibres). J. Cell. Physiol. 232: 1086-1094, 2017. © 2016 Wiley Periodicals, Inc.

Effect of Conjugated Linoleic Acid Intake on Endurance Exercise Performance and Anti-fatigue in Student Athletes

“…The effect of training on CYP17A1 expression and testosterone biosynthesis was significantly higher in the trained mice supplemented with CLA compared with placebo. Barone et al 3 also reported that CLA supplementation induced hypertrophy of types I and IIb muscle fibers in plantaris and gastrocnemius muscles of mice by endurance exercise and induced only a specific hypertrophy of type IIx muscle fibers in the plantaris muscle. This study s participants were student athletes.…”

“…Kim and Park 32 reported that CLA treatment was shown to activate peroxisome proliferator-activated receptor γ coactivator 1α PGC-1α in C 2 C 12 mouse myoblasts; this was linked with upregulation of mitochondrial biogenesis. PGC-1α is a transcriptional coactivator that controls the expression of genes involved in regulation of fatty acid oxidation, glucose metabolism, and antioxidants 3 . It has been…”

“…Further study needs to investigate fat oxidation by analysis of expired gas. LD isozymes, LD [1][2][3][4][5] , in serum before and after exercise were measured in this study. Many previous studies measured total LD after exercise 38 43 .…”

“…Each blood sample, 2 mL in an EDTA tube and 7 mL in a plain tube, were collected from the antecubital vein. The following were determined: hematological value and serum level of creatine phosphokinase CK , glucose, triglyceride TG , non-esterified fatty acid NEFA , and isozymes of lactate dehydrogenase LD , LD [1][2][3][4][5] . These analyzes were conducted by LSI Medience Corporation Tokyo, Japan .…”

“…In particular, several human clinical trials have reported mixed results, with a few studies indicating that CLA reduces body fat mass or increases lean body mass LBM , although others showed no effects on body composition 13 15 . CLA has also been reported to improve muscle hypertrophy, steroidogenesis, physical activity, and endurance capacity in mice 3 .…”