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Abstract. The precise mechanisms of alopecia, a pathophysiological disorder with negative psychological implications, are unknown. Androgen and hereditary predisposition are major causes, but the condition is also affected by stress, an irregular diet and high levels of sebum secretion. We focused on oxidative stress and analyzed the effect of the lipid peroxides on hair follicles. Our first observation was that the topical application of linolein hydroperoxides, one of the lipid peroxides, lead to the early onset of the catagen phase in murine hair cycles. Furthermore, by using TUNEL staining we found that lipid peroxides induced apoptosis of hair follicle cells. They also induced apoptosis in human epidermal keratinocytes by up-regulating apoptosis-related genes. These results indicated that lipid peroxides, which can cause free radicals, induce the apoptosis of hair follicle cells, and this is followed by early onset of the catagen phase. These observations may provide insight into the mechanisms underlying the development of alopecia in humans.

SUMMARYActivation of adenosine A 2a receptors in cerebral neurons induces sleep in various mammals. It was previously found that Japanese sake yeast enriched in adenosine analogues activates A 2a receptors in vitro and induces sleep in mice. Here it is reported that sake yeast activated A 2a receptors in a cultured human cell line and improved human sleep quality in a clinical trial. Sake yeast activated A 2a receptors in HEK cells in a dose-dependent manner with an EC 50 of 40 lg mL À1 , and the activation was attenuated almost completely by the A 2a receptor antagonist ZM241385 with an IC 50 of 73 nM. In a double-blind placebo-controlled crossover clinical study, 68 healthy participants ingested tablets containing either 500 mg of sake yeast powder or a placebo (cellulose) 1 h before sleep for 4 days. Electroencephalograms were recorded during sleep at home with a portable device for 4 week days. Electroencephalogram analyses revealed that sake yeast supplementation significantly (P = 0.03) increased delta power during the first cycle of slow-wave sleep by 110%, without changing other sleep parameters. Sake yeast supplementation also significantly increased growth hormone secretion in the urine on awakening by 137% from 3.17 AE 0.41 (placebo) to 4.33 AE 0.62 (sake yeast) pg mg À1 creatinine (P = 0.03). Subjective sleepiness (P = 0.02) and fatigue (P = 0.06) in the morning were improved by sake yeast. Given these benefits and the absence of adverse effects during the study period, it was concluded that sake yeast supplementation is an effective and safe way to support daily high-quality, deep sleep.

No abstract

This study aimed to investigate the gut microbial genera associated with skeletal muscle mass, using a large-scale survey from the standpoint of preventing sarcopenia. A total of 848 participants were included in the analysis. The mean (SD) ages of men (n = 353) and women (n = 495) were 50.0 (12.9) years and 50.8 (12.8) years, respectively. Body composition was assessed using appendicular skeletal muscle mass/body weight (ASM/BW), ASM, and BW. Additionally, the relationship between gut microbial genera and body composition was analyzed. The means (SD) of ASM/BW were 34.9 (2.4) % in men and 29.4 (2.9) % in women. Blautia and Bifidobacterium were positively associated with ASM/BW only in men (Blautia: β = 0.0003, Bifidobacterium: β = 0.0001). However, Blautia was negatively associated with BW (β = −0.0017). Eisenbergiella was positively associated with ASM/BW (β = 0.0209) and negatively associated with BW (β = −0.0769) only in women. Our results indicate that Blautia, Bifidobacterium and Eisenbergiella, which are positively associated with ASM/BW, might help increase skeletal muscle mass. ASM/BW may clarify the relationship between gut microbiota and skeletal muscle mass without being affected by obesity or excess body fat mass.