Factors associated with serum retinol, alpha-tocopherol, carotenoids, and selenium in Hispanics with problems of HIV, chronic hepatitis C, and drug use.

The effects of hepatitis and drug use on nutritional problems in HIV infection have rarely been examined despite the importance of drug use in the global HIV pandemic. We examined the effects of HIV, hepatitis C, and drug use on serum micronutrients in 300 US Hispanic adults. Chronic hepatitis C infection was associated with lower serum retinol (-8.2 microg/dl, P < 0.0001), alpha-tocopherol (-0.10 ln microg/dl, P = 0.024), and carotenoids (-19.8 microg/dl, P < 0.0001). HIV infection was associated with lower selenium (-6.1 microg/l, P = 0.028). Elevated triglycerides in HIV infection were associated with higher serum retinol and alpha-tocopherol. Drug use was not independently associated with micronutrient alterations. We conclude that hepatitis C is an important determinant of low serum micronutrients, and should be considered in any nutritional assessment of HIV infected populations. As the safety of micronutrient supplementation is not established, policy for appropriate HIV clinical care should distinguish between populations with and without hepatitis coinfection.

Lycium barbarum (goji) juice improves in vivo antioxidant biomarkers in serum of healthy adults.

Although Lycium barbarum (goji) and active compounds, Lycium barbarum polysaccharides (LBP), have a high in vitro antioxidant score as determined by simple chemical reaction methods, their in vivo antioxidant effects in humans have not been extensively examined. After our earlier report that an LBP-standardized Lycium barbarum preparation (GoChi) helps prevent oxidant stress-related conditions in humans, our present study examined the hypothesis that the antioxidant effects of GoChi result from its ability to enhance endogenous antioxidant factors. We investigated the effects of GoChi in a 30-day randomized, double-blind, placebo-controlled clinical study. The study population included 50 Chinese healthy adults aged 55 to 72 years. In vivo antioxidant markers, consisting of serum levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and lipid peroxidation (indicated by decreased levels of malondialdehyde, MDA) were examined preintervention and postintervention with GoChi or placebo (120 mL/d). In the GoChi group, antioxidant markers significantly increased by 8.4% for SOD and 9.9% for GSH-Px between the preintervention and postintervention measurements, whereas MDA were significantly decreased by 8.7%. In addition, the SOD, GSH-Px, and MDA levels in the GoChi group were significantly different from those in the placebo group at the postintervention time point, with increases of 8.1% and 9.0% and a decrease of 6.0%, respectively. No significant differences were detected between the preintervention and postintervention time points in the placebo group. These results indicate that GoChi increased antioxidant efficacies in humans by stimulating endogenous factors and suggest that continued use beyond 30 days might help prevent or reduce free radical-related conditions.

Garlic reduces dementia and heart-disease risk.

Risk factors for cardiovascular disease, including high cholesterol, high homocysteine, hypertension and inflammation, increase the risk of dementia, including its most common form, Alzheimer's disease (AD). High cholesterol is also associated with elevated beta-amyloid (Abeta), the hallmark of AD. Oxidative damage is a major factor in cardiovascular disease and dementia, diseases whose risk increases with age. Garlic, extracted and aged to form antioxidant-rich aged garlic extract (AGE or Kyolic), may help reduce the risk of these diseases. AGE scavenges oxidants, increases superoxide dismutase, catalase, glutathione peroxidase, and glutathione levels, and inhibits lipid peroxidation and inflammatory prostaglandins. AGE reduces cholesterol synthesis by inhibiting 3-hydroxy-3-methylglutaryl-CoA reductase and is additive with statins in its action. Inhibition of cholesterol, LDL oxidation, and platelet aggregation by AGE, inhibits arterial plaque formation; AGE decreases homocysteine, lowers blood pressure, and increases microcirculation, which is important in diabetes, where microvascular changes increase heart disease and dementia risks. AGE also may help prevent cognitive decline by protecting neurons from Abeta neurotoxicity and apoptosis, thereby preventing ischemia- or reperfusion-related neuronal death and improving learning and memory retention. Although additional observations are warranted in humans, compelling evidence supports the beneficial health effects attributed to AGE in helping prevent cardiovascular and cerebrovascular diseases and lowering the risk of dementia and AD.

Dietary antioxidants and human cancer.

Epidemiological studies show that a high intake of anti-oxidant-rich foods is inversely related to cancer risk. While animal and cell cultures confirm the anticancer effects of antioxidants, intervention trials to determine their ability to reduce cancer risk have been inconclusive, although selenium and vitamin E reduced the risk of some forms of cancer, including prostate and colon cancer, and carotenoids have been shown to help reduce breast cancer risk. Cancer treatment by radiation and anticancer drugs reduces inherent antioxidants and induces oxidative stress, which increases with disease progression. Vitamins E and C have been shown to ameliorate adverse side effects associated with free radical damage to normal cells in cancer therapy, such as mucositis and fibrosis, and to reduce the recurrence of breast cancer. While clinical studies on the effect of anti-oxidants in modulating cancer treatment are limited in number and size, experimental studies show that antioxidant vitamins and some phytochemicals selectively induce apoptosis in cancer cells but not in normal cells and prevent angiogenesis and metastatic spread, suggesting a potential role for antioxidants as adjuvants in cancer therapy.