Adrenocorticotropin hormone (ACTH), which is secreted in response to psychological stress, plays an important role in the hair cycle. This study examined the mechanism by which ACTH affects the hair cycle using mice d...Adrenocorticotropin hormone (ACTH), which is secreted in response to psychological stress, plays an important role in the hair cycle. This study examined the mechanism by which ACTH affects the hair cycle using mice deficient in melanocortin receptor-2(MC2R<sup>-/-</sup>), which is a main receptor for ACTH. We observed the hair cycle using female MC2R<sup>-/-</sup> mice at 15 weeks old and five days old to determine whether there were any age-dependent differences. The 15-week-old MC2R<sup>-/-</sup> mice showed the anagen phase for all mice. On the other hand, all of the MC2R<sup>+/+</sup> mice showed the telogen phase at the same age. Moreover, in the five-day-old mice, the hair growth of the MC2R<sup>-/-</sup> mice occurred earlier than in the MC2R<sup>+/+</sup> mice. Both the 15-week-old and five-day-old MC2R<sup>-/-</sup> mice had higher levels of ACTH and alpha-melanocyte stimulating hormone in the blood than did the MC2R<sup>+/+</sup> mice. In addition, in the 15-week-old MC2R<sup>-/-</sup> mice, the hair cycle shifted to the telogen phase following the administration of a cyclic guanosine monophosphate (cGMP) inhibitor and MC1R/MC5R inhibitor. In the five-day-old MC2R<sup>-/-</sup> mice, the hair growth was slowed by the administration of corticosterone. These results suggest that the ACTH/MC2R system has an important role in the hair cycle.展开更多
<span style="font-family:;" "=""><strong>Introduction</strong>:</span><span><span><span style="font-family:;" "=""> <i>...<span style="font-family:;" "=""><strong>Introduction</strong>:</span><span><span><span style="font-family:;" "=""> <i>Momordica charantia</i> (MC) has been reported to possess various beneficial effects. Improvement in natural aging of the skin has been observed with the use of MC. However, few studies have detailed the effects of MC on atopic dermatitis (AD). Therefore, in this study, we investigated the effects of MC on the skin symptoms of AD. <b>Methods:</b> Specific pathogen-free <span>and conventional NC/Nga mice were orally administered a 50 mg/kg/day</span> dose of MC every day for 2 weeks. <b>Results:</b> The expression levels of lipopolysaccharide (LPS), inducible nitric oxidase synthase (iNOS), and prostaglandin E2 (PGE2) remarkably increased in AD, but were suppressed by MC administration. As a result, the degradation of filaggrin by PGE2 was suppressed. Furthermore, in AD, iNOS induced macrophage type 1 and increased NO levels. <span>In contrast, due to suppression of iNOS with MC administration, macro</span><span>phages shifted to type 2 and an increase in L-ornithine was observed, which</span> subsequently promoted filaggrin synthesis. <b>Conclusions:</b> </span></span></span><span><span><span style="font-family:;" "="">These findings indicate that the AD-like skin symptoms were decelerated by MC via the regu<span>lation of the LPS/iNOS/PGE2/filaggrin and LPS/iNOS/Arginase 1/L-ornithine/ </span>filaggrin signaling pathways.</span></span></span>展开更多
文摘Adrenocorticotropin hormone (ACTH), which is secreted in response to psychological stress, plays an important role in the hair cycle. This study examined the mechanism by which ACTH affects the hair cycle using mice deficient in melanocortin receptor-2(MC2R<sup>-/-</sup>), which is a main receptor for ACTH. We observed the hair cycle using female MC2R<sup>-/-</sup> mice at 15 weeks old and five days old to determine whether there were any age-dependent differences. The 15-week-old MC2R<sup>-/-</sup> mice showed the anagen phase for all mice. On the other hand, all of the MC2R<sup>+/+</sup> mice showed the telogen phase at the same age. Moreover, in the five-day-old mice, the hair growth of the MC2R<sup>-/-</sup> mice occurred earlier than in the MC2R<sup>+/+</sup> mice. Both the 15-week-old and five-day-old MC2R<sup>-/-</sup> mice had higher levels of ACTH and alpha-melanocyte stimulating hormone in the blood than did the MC2R<sup>+/+</sup> mice. In addition, in the 15-week-old MC2R<sup>-/-</sup> mice, the hair cycle shifted to the telogen phase following the administration of a cyclic guanosine monophosphate (cGMP) inhibitor and MC1R/MC5R inhibitor. In the five-day-old MC2R<sup>-/-</sup> mice, the hair growth was slowed by the administration of corticosterone. These results suggest that the ACTH/MC2R system has an important role in the hair cycle.
文摘<span style="font-family:;" "=""><strong>Introduction</strong>:</span><span><span><span style="font-family:;" "=""> <i>Momordica charantia</i> (MC) has been reported to possess various beneficial effects. Improvement in natural aging of the skin has been observed with the use of MC. However, few studies have detailed the effects of MC on atopic dermatitis (AD). Therefore, in this study, we investigated the effects of MC on the skin symptoms of AD. <b>Methods:</b> Specific pathogen-free <span>and conventional NC/Nga mice were orally administered a 50 mg/kg/day</span> dose of MC every day for 2 weeks. <b>Results:</b> The expression levels of lipopolysaccharide (LPS), inducible nitric oxidase synthase (iNOS), and prostaglandin E2 (PGE2) remarkably increased in AD, but were suppressed by MC administration. As a result, the degradation of filaggrin by PGE2 was suppressed. Furthermore, in AD, iNOS induced macrophage type 1 and increased NO levels. <span>In contrast, due to suppression of iNOS with MC administration, macro</span><span>phages shifted to type 2 and an increase in L-ornithine was observed, which</span> subsequently promoted filaggrin synthesis. <b>Conclusions:</b> </span></span></span><span><span><span style="font-family:;" "="">These findings indicate that the AD-like skin symptoms were decelerated by MC via the regu<span>lation of the LPS/iNOS/PGE2/filaggrin and LPS/iNOS/Arginase 1/L-ornithine/ </span>filaggrin signaling pathways.</span></span></span>
