Silymarin Prevents High-Fat Diet-Induced Muscle Atrophy by Regulating Protein Degradation and Synthesis in Mice.

Silymarin is found in Silybum marianum. We investigated the effect of silymarin on muscle atrophy in obese mice. The experimental mice were divided into three groups: CON, normal diet; HFD, 60% high-fat diet (HF); and SILY: 50 mg silymarin +60% HF. It was confirmed that increases in body weight and fat mass in the SILY group were significantly inhibited. Moreover, the muscle mass in SILY mice was significantly higher than that in the HFD group. The grip strength in HFD group was significantly reduced, whereas in the SILY group it was higher than that in HFD group. In HFD mice, the mRNA levels of protein degradation factors (muscle ring-finger protein 1 [MuRF-1] and Atrogin-1) were increased and protein synthesis factors (phosphoinositide 3-kinase [PI3K] and Akt) were decreased. However, silymarin was found to elevate the degradation factors as compared with HFD group, whereas it reduced the synthesis factors. The results suggest that silymarin could prevent not only obesity but also muscle atrophy.

Fermented Curcuma longa L. Prevents Alcoholic Fatty Liver Disease in Mice by Regulating CYP2E1, SREBP-1c, and PPAR-α.

We examined the efficacy of fermented Curcuma longa L. (FT) on the development of alcoholic fatty liver in mice and investigated the underlying mechanism. The protective potential of FT against ethanol-induced fatty liver was determined using C57BL/6 male mice allocated into four groups (8 mice/group). Control groups received either distilled water or 5 g/kg body weight (b.w.) per day ethanol for 8 days. Treatment groups were administered either 300 mg/kg b.w. per day of milk thistle or FT before receiving ethanol. FT contained a higher amount of caffeic acid and tetrahydrocurcumin than C. longa. FT pretreatment significantly suppressed the elevated hepatic lipid droplets associated with ethanol ingestion. In comparison with ethanol-treated control, FT pretreated mice showed inhibited cytochrome P4502E1 (CYP2E1), sterol regulatory element-binding protein-1 (SREBP-1c), and acetyl-CoA carboxylase production but elevated AMP-activated protein kinase, peroxisome proliferator-activated receptor-alpha (PPAR-α), and carnitine palmitoyltransferase 1 (CPT-1) levels. Taken together, FT is a promising hepatoprotectant for preventing of alcoholic fatty liver through modulating fatty acid synthesis and oxidation.

Curcuma longa L. Water Extract Enhances Endurance Exercise Capacity by Promoting Intramuscular Mitochondrial Biogenesis in Mice.

We investigated the effect of Curcuma longa L. extract on endurance exercise capacity (EEC). EEC is the ability to exercise continuously and recover quickly, even when tired. C. longa contains antioxidants that contribute beneficial effects on the body. We separated groups of nonexercise (CON), exercise control (Ex-CON), branched-chain amino acid (BCAA) intake, and C. longa water extract (CLW) intake (Ex-CLW). EEC increased on the 28th day of BCAA and CLW intake. Both treatment groups exhibited decreased lactate levels with increased levels of nonesterified fatty acids and muscular glycogen compared with the Ex-CON group. Also, the Ex-CLW group possessed higher intramuscular antioxidant enzyme activities (catalase, superoxide dismutase, and glutathione peroxidase) than the Ex-CON group. The expression of PGC-1α, NRF, and Tfam, which are factors related to mitochondrial biogenesis, increased in the Ex-CLW group. Results suggest that CLW intake elevated EEC by increasing intramuscular mitochondrial biogenesis through suppressing the accumulation of fatigue substances and increasing fat consumption, and antioxidant enzyme activity.

Ethanolic Extract of Vaccinium corymbosum Alleviates Muscle Fatigue in Mice.

The aim of this study was to evaluate the effects of ethanol extracts of Vaccinium corymbosum (VCE) on exercise-induced fatigue in mice. Mice were randomly divided into three groups; nonexercise control group (CON), exercise control group (Ex-CON), and exercise and VCE supplementation group (Ex-VCE). Compared with Ex-CON, Ex-VCE showed increased endurance exercise capacity on day 21. In Ex-VCE mice, the accumulation of lactate was inhibited and the consumption of fatty acids was enhanced, indicating the delay of muscle fatigue. In addition, VCE supplementation elevated mRNA expression levels of mitochondrial biogenesis-associated genes such as peroxisome proliferator-activated receptor-1γ coactivator 1α (PGC-1α), nuclear respiratory factor (NRF), and mitochondrial transcription factor A (Tfam) and fatty acid ß-oxidation-associated genes such as carnitine palmitoyltransferase-1 (CPT-1), ß-hydroxyacyl coenzyme A dehydrogenase (ß-HAD), and peroxisome proliferator-activated receptor-δ (PPAR-δ). These results suggest that VCE can potentially prevent muscle fatigue by enhancing mitochondrial biogenesis and fatty acid ß-oxidation.

Immunomodulatory Effect of a Salvia plebeia R. Aqueous Extract in Forced Swimming Exercise-induced Mice.

This study investigated the immunomodulatory effect of Salvia plebeia R. aqueous extract (FIE-SP, SPW) in forced swimming exercise-induced mice and the immunostimulatory effects on Raw264.7 cells. Mice were randomly assigned to four groups: the control group (CON), the forced swimming test group (FST), and two FIE-SP groups (low and high dose of FIE-SP). Compared with the control group, the FIE-SP groups showed significantly increased ratios of T lymphocyte surface markers CD4+/CD8+ and major histocompatibility complex (MHC)I/MHCII, as well as increased concentrations of immunoglobulin (Ig)A and IgG. FIE-SP groups significantly increased Th1 cytokines and decreased Th2 cytokines compared with negative control exercise-induced mice. Conversely, the immunostimulatory effects of FIE-SP significantly increased phagocytic activities, nitric oxide (NO) production, and pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1ß in Raw264.7 cells. Furthermore, FIE-SP increased natural killer (NK) cell activities and cytokines (IL-12) in splenocytes compared with the CON group. These results indicated that FIE-SP supplementation could prevent imbalanced immune states and produce immunostimulatory effects to support innate immunity.

Water Extract of Curcuma longa L. Ameliorates Non-Alcoholic Fatty Liver Disease.

Our aim was to investigate whether hot water extract (CLW) of Curcuma longa L. could prevent non-alcoholic fatty liver disease (NAFLD). HepG2 cells were treated with free fatty acid (FFA) mixture (oleic acid: palmitic acid, 2:1) for 24 h to stimulate in vitro fatty liver. In addition, C57BL/6 mice were fed 60 kcal% high-fat (HF) diet for eight weeks to induce fatty liver in vivo. Intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) productions were increased by FFA and HF-diet, but supplementation with CLW significantly decreased these levels. CLW treatment ameliorated antioxidant activities that were suppressed by exposure to the FFA and HF-diet. Cluster of differentiation 36 (CD36) and fatty acid transport proteins (FATP2 and FATP5) were increased in HF-diet groups, while CLW suppressed their expression levels. Moreover, sterol regulatory element-binding protein-1c (SREBP-1c), acetyl-coenzyme A carboxylase (ACC), and fatty acid synthase (FAS) expression levels were down-regulated in the CLW groups compared to HF-diet groups. On the other hand, 5' adenosine monophosphate-activated protein kinase (AMPK), Peroxisome proliferator-activated receptor alpha (PPAR-α), and carnitine palmitoyltransferase 1 (CPT-1) expressions were up-regulated in the CLW groups. HF-diet fed mice showed high hepatic triglycerides (TG) content compared to the normal diet mice. However, the administration of CLW restored the hepatic TG level, indicating an inhibitory effect against lipid accumulation by CLW. These results suggest that CLW could be a potentially useful agent for the prevention of NAFLD through modulating fatty acid uptake.