Effect of Cblin and celastrol on muscle atrophy

Two novel reagents, N-myristoylated Cbl-b inhibitory peptide (C14-Cblin) and celastrol, a quinone methide triterpene, are reported to be effective in preventing myotube atrophy. The combined effects of C14-Cblin and celastrol on rat L6 myotubes atrophy induced by 3D-clinorotation, a simulated microgravity model, was investigated in the present study. We first examined their effects on expression in atrogenes. Increase in MAFbx1/atrogin-1 and MuRF-1 by 3D-clinorotation was significantly suppressed by treatment with C14-Cblin or celastrol, but there was no additive effect of simultaneous treatment. However, celastrol significantly suppressed the upregulation of Cbl-b and HSP70 by 3D-clinorotation. Whereas 3D-clinorotation decreased the protein level of IRS-1 in L6 myotubes, C14-Cblin and celastrol inhibited the degradation of IRS-1. C14-Cblin and celastrol promoted the phosphorylation of FOXO3a even in microgravity condition. Simultaneous administration of C14-Cblin and celastrol had shown little additive effect in reversing the impairment of IGF-1 signaling by 3D-clinorotation. While 3D-clinorotation-induced marked oxidative stress in L6 myotubes, celastrol suppressed 3D-clinorotation-induced ROS production. Finally, the C14-Cblin and celastrol-treated groups were inhibited decrease in L6 myotube diameter and increased the protein content of slow-twitch MyHC cultured under 3D-clinorotation. The simultaneous treatment of C14-Cblin and celastrol additively prevented 3D-clinorotation-induced myotube atrophy than single treatment

Is Estrogen Effective for Full-Thickness Cutaneous Wound Healing in Young Male Mice ?

The aim of this study is to show the effects of estrogen upon its topical application on the wound healing process in young male mice. Fifty-six male mice aged 7 weeks old were divided into 4 groups: sham operation, castration, estrogen treatment after sham operation, and estrogen treatment after castration. Wound healing was observed daily until day 14 after wounding. Specimens were harvested on days 3, 7, 10, and 14, and stained to evaluate reepithelialization, inflammation, contraction, and collagen accumulation. Wound healing periods of all groups were almost the same, although the concentration of serum estrogen in the estrogen-applied mice was very high, and that in the nonapplied groups was low. The numbers of macrophages in the castrated, estrogen-treated after sham operation, and estrogen-treated after castration groups were significantly decreased compared with that in the sham group in the inflammatory phase; however, the ratio of wound area in these groups did not decrease, and other histological data did not reveal any effects of estrogen. These results indicate that estrogen may show limited effectiveness for full-thickness cutaneous wound healing in young male mice, and decreased inflammation may not always be associated with decreased wound area

Essential role of the cytochrome P450 CYP4F22 in the production of acylceramide, the key lipid for skin permeability barrier formation

A skin permeability barrier is essential for terrestrial animals, and its impairment causes several cutaneous disorders such as ichthyosis and atopic dermatitis. Although acylceramide is an important lipid for the skin permeability barrier, details of its production have yet to be determined, leaving the molecular mechanism of skin permeability barrier formation unclear. Here we identified the cytochrome P450 gene CYP4F22 as the long-sought fatty acid ω- hydroxylase gene required for acylceramide production. CYP4F22 has been identified as one of the autosomal recessive congenital ichthyosis-causative genes. Ichthyosis mutant proteins exhibited reduced enzyme activity, indicating correlation between activity and pathology. Furthermore, lipid analysis of an ichthyosis patient showed a drastic decrease in acylceramide production. We determined that CYP4F22 was a type I membrane protein that locates in the endoplasmic reticulum (ER), suggesting that the ω-hydroxylation occurs on the cytoplasmic side of the ER. The preferred substrate of the CYP4F22 was ?C28 fatty acids. In conclusion, our findings demonstrated that CYP4F22 is an ultra long-chain fatty acid ω-hydroxylase responsible for acylceramide production and provides important new insights into the molecular mechanisms of skin permeability barrier formation. Furthermore, based on the results obtained here, we proposed a detailed reaction series for acylceramide production

Quantitative Proteome Analysis in Response to Glucose Concentration in C2C12 Myotubes

Glucose is important for the maintenance of muscle function; however, it is still unclear how changes in glucose concentration affect muscle. Here, we analyzed the effect of glucose concentration on protein expression under different glucose concentration media in C2C12 myotubes. First, we performed proteome analysis in C2C12 myotubes cultured in Low (1.0 g/L), Medium (2.0 g/L), and High (4.5 g/L) glucose media. Proteome analysis revealed 113 proteins were significantly changed in group cultured in Low or Medium glucose media compared to group cultured in High glucose media. Furthermore, glycolysis, oxidative phosphorylation, and fatty acid metabolism were increased in the Medium and Low groups. Among these pathways, HK2, PFKP, NDUFA11, and FABP3 were especially upregulated proteins in Low and Medium groups. In this context, ATP production in C2C12 myotubes cultured in Low and Medium glucose media was increased. There was no significant change in myotubes morphology and myogenic differentiation factors in all groups. Finally, we examined the effect on glucose concentration in culture media on myosin isoforms expression by qRT-PCR. As a result, Myh2 and Myh4 were significantly increased in Low and Medium conditions. Altogether, Low and Medium glucose conditions induced Myh expression probably via enhancement glucose utilization

Does Instruction of Oral Health Behavior for Workers Improve Work Performance?—Quasi-Randomized Trial

Oral disease can cause economic loss due to impaired work performance. Therefore, improvement of oral health status and prevention of oral disease is essential among workers. The purpose of this study was to investigate whether oral health-related behavioral modification intervention influences work performance or improves oral health behavior and oral health status among Japanese workers. We quasi-randomly separated participants into the intervention group or the control group at baseline. The intervention group received intensive oral health instruction at baseline and a self-assessment every three months. Both groups received oral examinations and answered the self-questionnaire at baseline and at one-year follow-up. At follow-up, the prevalence of subjects who use fluoride toothpastes and interdental brushes/dental floss were significantly higher in the intervention group than in the control group. Three variables (tooth brushing in workplace, using fluoride toothpaste, and experience of receiving tooth brushing instruction in a dental clinic) showed significant improvement only in the intervention group. On the other hand, work performance and oral status did not significantly change in either group. Our intensive oral health-related behavioral modification intervention improved oral health behavior, but neither work performance nor oral status, among Japanese workers