Effects of Sunphenon and Polyphenon 60 on proteolytic pathways, inflammatory cytokines and myogenic markers in H2O2-treated C2C12 cells.

Abstract

The effect of Sunphenon and Polyphenon 60 in oxidative stress response, myogenic regulatory factors, inflammatory cytokines, apoptotic and proteolytic pathways on H2O2-induced myotube atrophy was addressed. Cellular responses of H2O2-induced C2C12 cells were examined, including mRNA expression of myogenic regulatory factors, such as MyoD and myogenin, inflammatory pathways, such as TNF-α and NF-kB, as well as proteolytic enzymes, such as μ-calpain and m-calpain. The pre-treatment of Sunphenon (50 μg/mL)/Polyphenon 60 (50 μg/mL) on H2O2-treated C2C12 cells significantly down-regulated the mRNA expression of myogenin and MyoD when compared to those treated with H2O2-induced alone. Additionally, the mRNA expression of μ-calpain and m-calpain were significantly(p<0.05) increased in H2O2-treated C2C12 cells, whereas pre-treatment with Sunphenon/Polyphenon significantly down-regulated the above genes, namely μ-calpain and m-calpain. Furthermore, the mRNA expression of TNF-α and NF-kB were significantly increased in H2O2-treated C2C12 cells, while pre-treatment with Sunphenon (50 μg/mL)/Polyphenon 60 (50 μg/mL) significantly (p<0.05) down-regulated it when compared to the untreated control group.Subsequent analysis of DNA degeneration and caspase activation revealed that Sunphenon (50 μg/mL)/Polyphenon 60 (50 μg/mL) inhibited activation of caspase-3 and showed an inhibitory effect on DNA degradation. From this result, we know that, in stress conditions, μ-calpain may be involved in the muscle atrophy through the suppression of myogenin and MyoD. Moreover, Sunphenon may regulate the skeletal muscle genes/promote skeletal muscle recovery by the up-regulation of myogenin and MyoD and suppression of μ-calpain and inflammatory pathways and may regulate the apoptosis pathways. Our findings suggest that dietary supplementation of Sunphenon might reduce inflammatory events in muscle-associated diseases, such as myotube atrophy.

• Authors: Allur Subramaniyan Sivakumar, Inho Hwang
• Journal: Journal of biosciences (J Biosci) Vol. 40 Issue 1 Pg. 53-9 (Mar 2015) ISSN: 0973-7138 [Electronic] India
• PMID: 25740141 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Flavonoids
• MyoD Protein
• MyoD1 myogenic differentiation protein
• Myogenin
• NF-kappa B
• Phenols
• RNA, Messenger
• Tumor Necrosis Factor-alpha
• Sunphenon
• Hydrogen Peroxide
• Calpain
• Caspase 3
• m-calpain
• mu-calpain

Topics

• Animals
• Apoptosis (drug effects)
• Calpain (genetics, metabolism)
• Caspase 3 (metabolism)
• Cell Line
• Enzyme Activation (drug effects)
• Flavonoids (pharmacology)
• Hydrogen Peroxide (pharmacology)
• Inflammation (drug therapy, immunology)
• Mice
• Muscle, Skeletal (metabolism, pathology)
• Muscular Atrophy (pathology)
• MyoD Protein (genetics, metabolism)
• Myogenin (genetics, metabolism)
• NF-kappa B (genetics, metabolism)
• Oxidative Stress (drug effects)
• Phenols (pharmacology)
• RNA, Messenger (biosynthesis)
• Tumor Necrosis Factor-alpha (genetics, metabolism)