The free phenols have been measured in 15 lagers, 6 porters and ales, and 11 light and nonalcoholic beers. Phenols were measured colorimetrically using an oxidation-reduction reaction with Folin-Ciocalteu reagent and catechin as the standard. The order of phenol concentration was ales > lagers > low calorie > nonalcoholic. The quality of antioxidants of the major phenols in beers and the quality of beer antioxidants were measured by (1) dose-response inhibition of lower density lipoprotein oxidation and (2) concentration of phenols in the beers at which 50% of the peroxide was destroyed in a luminescent assay for antioxidant activity. The beers' lipoprotein antioxidant quality was clearly superior to that of vitamin antioxidants and to that of the phenol ingredients, suggesting synergism among the antioxidants in the mixture. The average per capita consumption of beer in the United States in 2000 was 225 mL/day, equivalent to 42 mg/day of catechin equivalents. Beer provides more antioxidants per day than wine in the U.S. diet. A dark beer and a lager beer were given at two concentrations to cholesterol-fed hamsters, an animal model of atherosclerosis. At the high dose ((1)/(2)-diluted beer) both lager and dark beer significantly inhibited atherosclerosis compared to a control of 2% alcohol. At the high dose, lager significantly decreased cholesterol and triglycerides, and both beers acted as in vivo antioxidants by decreasing the oxidizability of lower density lipoproteins. At the low dose ((1)/(10)-diluted beer) only the lager beer significantly decreased atherosclerosis compared to the 0.4% alcohol control. The polyphenols in the beers appear to be responsible for the benefits of beer in this model. Lager beer inhibited atherosclerosis at a human equivalent dose in this hamster model of atherosclerosis.

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Biochemical evidence suggests that oxidative stress caused by accumulation of free radicals is involved in the pathogenesis of senile cataracts. If so, appropriate amounts of the antioxidant vitamins C and E might be expected to prevent or retard the process. Such activity has been observed in several in vitro and in vivo studies of experimentally-induced cataracts. A recent epidemiologic study found that cataract patients tended to have lower serum levels of vitamins C, E, or carotenoids than did control subjects. The present investigation, which compared the self-reported consumption of supplementary vitamins by 175 cataract patients with that of 175 individually matched, cataract-free subjects, revealed that the latter group used significantly more supplementary vitamins C and E (P = 0.01 and 0.004, respectively). Because the results suggested a reduction in the risk of cataracts of at least 50%, a randomized, controlled trial of vitamin supplementation in cataract prevention may be warranted.

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SUMMARYThe relation between cataract and calpain proteolysis of lens fodrin was studied in two systems: elevated glucose (55.6 mM, diabetic model), and cytochalasin D (CD, 10 2 mM, actin depolymerization-induced opacity model). Glucose treatment (48 h) caused a visible opaque layer and enzyme leakage, with a concomitant accumulation of ([Ca2+]¡) around the lens equatorial cortex. CD caused both earlier and greater opacity and enzyme leakage than glucose. Lens fodrin digestion occurred in parallel with the timing and extent of calcium elevation. A calpain inhibitor peptide (CIP, 10" 2 mM) reduced the proteolysis of fodrin, opacity, and enzyme leakage in glucose-treated lenses but only partially retarded them in CDtreated lenses. These results suggest a mechanism in which calpain proteolysis of fodrin is a critical event in lens damage during opacification of cortical cataract.

Experimental evidence suggests that oxidative stress due to the accumulation of free radicals plays a role in the pathogenesis of cataracts and that the process can be prevented or ameliorated by antioxidants. In addition, a recent study found that cataract patients tended to have lower serum levels of vitamins C, E, or carotenoids than did control subjects. This investigation, which compared the self-reported consumption of supplementary vitamins by 175 cataract patients with that of 175 individually matched, cataract-free subjects, revealed that the latter group used significantly more supplementary vitamins C and E (p = 0.01 and 0.004, respectively). Inasmuch as the observed reduction in risk of cataracts was at least 50%, a randomized, controlled trial of vitamin supplementation in cataract prevention seems justified.

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