Coffee brew intake can prevent the reduction of lens glutathione and ascorbic acid levels in HFD-fed animals.

The lens has high concentrations of glutathione (GSH) and ascorbic acid (AsA) to maintain redox activity and prevent cataract formation, which is the leading cause of visual impairment worldwide. Metabolic syndrome is reported to be linked with a higher risk of age-associated cataract. As it was demonstrated previously that coffee consumption improved high-fat diet (HFD) -induced metabolic symptoms, it was hypothesized that coffee intake could delay the onset of obesity related-cataract; however, the effect of coffee consumption on this type of cataract remains unknown. Four-week-old male C57BL/6JJms SLC mice were divided into two groups and were provided ad libitum access to either a control diet (control groups) or a HFD (HFD groups). The control groups and HFD groups were further divided into three or four subgroups for each experiment. Coffee intake markedly reduced the increase in body weight in a roasting-time and concentration-dependent manner. Coffee consumption also prevented the HFD-induced decrease in the concentration of GSH and AsA, and treatment with pyrocatechol or caffeine also restored the reduction of antioxidant compounds. Plasma cholesterol and triglycerides were significantly higher in HFD groups; however, coffee brew or coffee constituent treatment in the HFD-fed mice group prevented elevation of these levels. Caffeine is a major coffee component and pyrocatechol is generated thought the roasting process. These results revealed that caffeine and pyrocatechol in coffee brew may be the key constituents responsible for preventing the reduction of lens GSH and AsA in HFD-fed animals.

Administration of antioxidant compounds affects the lens chaperone activity and prevents the onset of cataracts.

To prevent lens opacification and cataract formation, the lens contains α-crystallin, which has been shown to function as a molecular chaperone that maintains the correct folding of other proteins. Oxidative stress is known to be an important factor in the initiation and progression of a cataract. So far, several antioxidant compounds have been reported to prevent cataracts in vivo and in vitro. This stress also triggers α-crystallin modifications and alters its chaperone activity. However, few studies have examined the relationship between the consumption of antioxidant compounds and lens chaperone activity. To elucidate the effect of antioxidants on lens chaperone activity, antioxidants were administered to a selenite-induced cataract model of rats. The chaperone activity in lens water-soluble fraction was measured using aldehyde dehydrogenase. All antioxidant treatment groups, except decaffeinated coffee treatment, had less severe central opacities and lower stage cataracts than control groups. The chaperone activity was weaker in lens of selenite cataract rats, but antioxidant compounds and coffee treatment can prevent the chaperone activity decreasing, but not decaffeinated coffee. These results suggested that the treatment with antioxidant compounds could prevent cataract formation by the maintenance of the chaperone activity in water-soluble lens proteins. Thus, this study describes the development of an anticataract drug target for lens chaperone activity.

Roasting Enhances the Anti-Cataract Effect of Coffee Beans: Ameliorating Selenite-Induced Cataracts in Rats.

PURPOSE: Coffee is a widely consumed beverage. While recent studies have linked its intake to a reduced risk of cataracts, caffeine is believed to be the key factor for its effect. To know how roasting beans affects the effect of coffee on cataract formation, we investigated the impact roasting using a selenite-induced cataract rat model. MATERIALS AND METHODS: Sprague Dawley rats were given a single injection of sodium selenite, which induced formation of nuclear cataracts by day 6, with or without coffee intake (100% coffee, 0.2 mL/day) for following 3 days. RESULTS: The concentrations of glutathione (GSH) and ascorbic acid (AsA) in selenite-induced cataract lenses declined to half that of controls. However, 3 days of coffee intake ameliorated the reduction of GSH and AsA so that concentrations remained at 70-80% that of controls. Roasting enhanced the preventive effect of coffee by further reducing cataract formation and ameliorating selenite-induced reduction of antioxidants. High-performance liquid chromatography analysis revealed degradation of chlorogenic acid and generation of pyrocatechol during the coffee roasting process. We discovered that pyrocatechol, at doses equivalent to that found in dark-roasted coffee, was equally effective as caffeine at reducing cataract formation and ameliorating the reduction of antioxidants. CONCLUSION: Our results indicate that pyrocatechol, generated during the roasting process, acts as an antioxidant together with caffeine to prevent cataract formation.

Season- and age-related reproductive changes based on fecal androgen concentrations in male koalas, Phascolarctos cinereus.

The purposes of the present study were to clarify age- and season- related androgen patterns, and to compare the reproductive physiology between Japanese captive koala populations and Australian populations. To measure fecal androgens, feces were collected from male koalas (4.2 to 13.8 years of age) kept in Japanese zoos. Fecal androgens were extracted with methanol from the lyophilized samples and determined by enzyme immunoassay using 4-androstene-3,17-dione antibody. Fecal androgen concentration in male koalas increased after sexual maturation and remained relatively high until old age. In the survey with the Japanese zoo studbook of koalas, copulation (conception) month showed a pyramid shape with a peak in March to June (60.7%) in koalas born and reared in Japanese zoos and from July to April with the highest concentration in September to January (69.7%) in Australian institutes. Japanese zoo koala populations have a characteristic physiological cycle adapted to Japan's seasonal changes. The suitable month of year for copulation or conception in Japan is diametrically opposed to that in Australia. Mean fecal androgen concentrations by month in the males born and reared in Japan indicated annual changes with the highest concentration in May and the lowest value in November. Fecal androgen analysis may be a noninvasive alternative tool to monitor circulating testosterone and may be helpful in understanding reproductive activity and physiology in male koalas.