Weight Loss Sale

Life Extension Magazine

LE Magazine November 2008
image

Soy Isoflavones, Curcumin Synergize to Thwart Pancreatic Cancer

Soy isoflavones and curcumin work together to decrease activation of genes that help cancer cells survive, and could help avert pancreatic cancer, a new study reveals.* Pancreatic cancer remains the fourth leading cause of cancer deaths, and effective prevention and treatment strategies are greatly needed.

Noting that pancreatic cancer incidence is relatively low among Asians, American researchers wondered if traditional Asian dietary elements, such as soy isoflavones and curcumin might offer anti-cancer activity.

The scientists added isoflavones and curcumin, individually and in combination, to pancreatic cancer cell cultures. Their results revealed that “inhibition of cell growth and induction of apoptosis [cellular suicide] was significantly greater in the combination group than could be achieved by either agent alone.”

Soy isoflavones and curcumin may work by suppressing the activity of nuclear factor-kappa B (NF-kB), a key regulator of inflammatory and immune responses that is believed to play an important role in the progression of cancer.

—Dale Kiefer

Reference

* Wang Z, Desmoulin S, Banerjee S, et al. Synergistic effects of multiple natural products in pancreatic cancer cells. Life Sci. 2008 Aug 15;83(7-8):293-300.

Lycopene Lowers Lipids, Slows Accumulation of Atherosclerotic Plaque

Lycopene slowed the development of atherosclerosis in rabbits fed a high-fat diet, similar to the effects of fluvastatin, a new study reports.* Lycopene is a carotenoid found at high levels in tomatoes that has an antioxidant effect. Statin drugs like fluvastatin prevent atherosclerosis by suppressing the accumulation and oxidation of low-density lipoprotein (LDL).

Forty rabbits were treated in one of five groups: a standard diet (control), a high-fat diet alone, a high-fat diet with 4 mg/kg or 12 mg/kg lycopene, or a high-fat diet with 10 mg/kg fluvastatin.

After eight weeks, all treated groups had significantly lower levels of total cholesterol, triglycerides, and LDL compared with the high-fat diet alone. Both lycopene and fluvastatin reduced atherosclerotic plaque formation, but lycopene was superior to fluvastatin for decreasing lipid levels, oxidized LDL, and inflammation.

Overall, the authors conclude, “these findings provide a theoretical rationale for the use of lycopene as a preventive and therapeutic drug in atherosclerosis.”

—Laura J. Ninger, ELS

Reference

* Hu MY, Li YL, Jiang CH, Liu ZQ, Qu SL, Huang YM. Comparison of lycopene and fluvastatin effects on atherosclerosis induced by a high-fat diet in rabbits. Nutrition. 2008 Jun 26.

Resveratrol Slows Aging in Mice

Resveratrol Slows Aging in Mice

Resveratrol, a compound found in red grapes and other foods, attenuates the effects of aging in mice,* similar to benefits previously found with calorie-restricted diets. Research has shown that resveratrol extends the life span of certain yeast, worms, flies, and fish.

Experimental mice were treated with dietary restriction (every-other-day feeding), a high-calorie diet, or a standard (control) diet, each group either with or without resveratrol. Regardless of the diet, resveratrol supplementation for about one year suppressed age-related cardiovascular disease, osteoporosis, cataracts, and decline in motor coordination, similar to dietary restriction. In treated mice, liver and muscle tissues resembled those in younger animals.

The benefits of resveratrol may be due to antioxidant and anti-inflammatory effects. Resveratrol may become useful in humans to mimic some of the beneficial effects of dietary restriction without actually decreasing caloric intake.

—Laura J. Ninger, ELS

Reference

* Pearson KJ, Baur JA, Lewis KN, et al. Resveratrol delays age-related deterioration and mimics transcriptional aspects of dietary restriction without extending life span. Cell Metab. 2008 Jul 2.

Broccoli Reduces Prostate Cancer Risk

Epidemiological studies suggest that men who consume at least one serving of cruciferous vegetables per week (e.g. broccoli, cauliflower, cabbage, etc.) are less likely to develop prostate cancer.* It’s believed that chemical compounds called isothiocyanates are responsible for this protective effect, but efforts to understand the mechanisms at work have previously involved tissue culture or animal models. Now, a year-long study with human volunteers has further illuminated this phenomenon under real-life conditions.*

British researchers randomly assigned subjects to consume either a broccoli-rich or a pea-rich control diet for 12 months. Subjects’ prostates were biopsied before, during, and after the study period, and differences in gene expression were scrutinized. Analyses revealed that more changes in gene expression occurred among men on the broccoli-rich diet, reaching significance within six months.

“Consuming broccoli…result[s] in complex changes to signaling pathways associated with inflammation and carcinogenesis in the prostate,” concluded researchers. These changes in gene expression may account for the observation that “diets rich in cruciferous vegetables may reduce the risk of prostate cancer and other chronic disease.”

—Dale Kiefer

Reference

* Traka M, Gasper AV, Melchini A, et al. Broccoli consumption interacts with GSTM1 to perturb oncogenic signalling pathways in the prostate. PLoS ONE. 2008 Jul 2;3(7):e2568.

Pomegranate Extract Inhibits Inflammation

Pomegranate Extract Inhibits Inflammation

Pomegranate extract inhibited inflammatory activity in blood isolated from treated rabbits.* Pomegranate is known to have beneficial antioxidant and anti-inflammatory properties.

In this study, four rabbits were given 10 mL of pomegranate fruit extract (equivalent to 175 mL of pomegranate juice), and two control animals received water. Blood was collected two hours later and incubated with either cyclooxygenase enzymes (COX-1 and COX-2, involved in inflammation) or with rabbit cartilage cells (chondrocytes) to test the effect of pomegranate-treated blood on inflammatory processes.

Plasma samples from treated rabbits significantly inhibited COX-1 and especially COX-2 activity as compared with untreated plasma. Treated plasma samples also inhibited the production of inflammatory mediators nitric oxide and prostaglandin E2 in chondrocytes.

The authors believe these actions suggest a future role in the treatment of arthritis: “…consumption of pomegranate fruit extract may be of value in inhibiting inflammatory stimuli-induced cartilage breakdown and production of inflammatory mediators in arthritis.”

—Laura J. Ninger, ELS

Reference

* Shukla M, Gupta K, Rasheed Z, Khan KA, Haqqi TM. Bioavailable constituents/metabolites of pomegranate (Punica granatum L) preferentially inhibit COX2 activity ex vivo and IL-1beta-induced PGE2 production in human chondrocytes in vitro. J Inflamm (Lond). 2008 Jun 13;5:9.

Calorie Restriction Decreases Oxidative Stress, Increases Life Span

The healthful benefits of calorie restriction may be related to decreased oxidative stress associated with consuming fewer calories, rather than decreased energy intake alone, according to a new report.* Calorie restriction extends life span in experimental animals, and has been associated with numerous health benefits in humans.

Researchers studied aged mice, which received either a calorie-restricted diet, or a calorie-restricted diet rich in advanced glycation end products (AGEs). AGEs induce oxidative stress, which is correlated with organ dysfunction and decreased life span.

Old mice fed the reduced-calorie diet laced with AGEs developed blood markers of oxidative stress, followed by insulin resistance, heart and kidney damage, and decreased longevity. Virtually identical mice, which consumed the simple calorie-restricted diet, experienced no such signs of oxidative stress, and lived longer than their counterparts.

“Therefore,” concluded researchers, “the beneficial effects of a [calorie restricted] diet may be partly related to reduced oxidant intake, a principal determinant of oxidant status in aging mice, rather than decreased energy intake.”

—Dale Kiefer

Reference

* Cai W, He JC, Zhu L, et al. Oral glycotoxins determine the effects of calorie restriction on oxidant stress, age-related diseases, and life span. Am J Pathol. 2008 Aug;173(2):327-36.