Life Extension Magazine October 2004
Green Tea Slows Brain Aging in Mice
Life Extension Magazine October 2004
|LE Magazine October 2004|
|Green Tea Slows Brain Aging in Mice|
Japanese scientists recently announced that antioxidants in green tea significantly slowed brain aging in laboratory mice.1
Green tea catechins slowed or halted symptoms of cognitive decline and senescence in mice specially bred for accelerated brain aging. The mice served as a model of age-associated senescence in humans. Catechins are a class of natural compounds (including epigallocatechin gallate, or EGCG) that neutralize free radicals, preventing oxidative damage.
Previous research has indicated that age-related cognitive dysfunction is associated with damage to brain tissues caused by oxidation.2 The brain requires significantly more oxygen than other tissues and
In the Japanese study, scientists gave green tea catechins daily to one group of mice and withheld catechins from a second group. At the end of 12 months, they tested both groups’ ability to learn certain tasks. The animals’ brains were subsequently examined for physical differences. Mice that received catechins performed significantly better on memory and learning tasks than mice that did not receive the antioxidants. The mice given green tea also had significantly healthier brain tissue upon post-mortem examination.
1. Unno K, Takabayashi F, Kishido T, Oku N. Suppressive effect of green tea catechins on morphologic and functional regression of the brain in aged mice with accelerated senes- cence (SAMP10) Exp. Gerontol. 2004 Jul;39(7):1027-34.
2. Forster MJ, Dubey A, Dawson KM, Stutts WA, Lal H, Sohal RS. Age-related losses of cognitive function and motor skills in mice are associated with oxidative protein damage in the brain. Proc Natl Acad Sci USA. 1996 May 14;93(10):4765-9.
3. Moriguchi T, Saito H, Nishiyama N. Anti-aging effect of aged garlic extract in the inbred brain atrophy mouse model. Clin Exp Pharmacol Physiol. 1997 Mar-Apr;24(3- 4):235-42.
4. Nishiyama N, Moriguchi T, Saito H. Beneficial effects of aged garlic extract on learning and memory impairment in the senescence-accelerated mouse. Exp Gerontol. 1997 Jan-Apr;32(1-2):149-60.
5. Fukui K, Omoi NO, Hayasaka T, et al. Cognitive impairment of rats caused by oxidative stress and aging and its prevention by vitamin E. Ann NY Acad Sci. 2002 Apr;959:275-84.
|Ginger Inhibits Inflammatory Activity|
Although mainly familiar to Westerners as a pungent cooking ingredient, ginger rhizome (Zingiber officinale) has long been used in the Far East to treat ailments such as nausea, headache, and knee pain resulting from osteoarthritis.
Last winter, scientists in Texas examined ginger root extract’s effects on cartilage cells that had been removed from osteoarthritic pigs and grown in the laboratory. Arthritis occurs when cartilage degrades and becomes inflamed in the knee or other joints. The researchers concluded that ginger extract inhibited the production of nitric oxide and prostaglandin E2, both of which are implicated in the inflammatory cascade that accompanies arthritis.1
Japanese scientists recently isolated a component of one species of ginger that exhibits powerful anti-inflammatory properties in human cells. Known as Zerumbone, the chemical also markedly suppressed the growth of, and induced apoptosis in, leukemia and colon cancer cells in the laboratory.2
A number of studies have indicated that ginger offers significant anti-inflammatory activity.3-6 Still others have shown that ginger relieves inflammation by inhibiting inflammation mediators such as prostaglandin E2 and thromboxane B2. Ginger is exceptionally well tolerated and has an excellent safety record.
1. Shen CL, Hong KJ, Kim SW. Effects of gin- ger (Zingiber officinale Rosc.) on decreasing the production of inflammatory mediators in sow osteoarthrotic cartilage explants. J Med Food. 2003;6(4):323-8.
2. Murakami A, Takahashi D, Kinoshita T, et al. Zerumbone, a Southeast Asian ginger sesquiterpene, markedly suppresses free radical generation, proinflammatory protein production, and cancer cell proliferation accompanied by apoptosis: the alpha, beta- unsaturated carbonyl group is a prerequisite. Carcinogenisis. 2002 May;23(5):795-802.
3. Wigler I, Grotto I, Caspi D, Yaron M. The effects of Zintona EC (a ginger extract) on symptomatic gonarthritis. Osteoarthritis Cartilage. 2003 Nov;11(11):783-9.
4. Bliddal H, Rosetzsky A, Schlichting P, et al. A randomized, placebo-controlled, cross-over study of ginger extracts and ibuprofen in osteoarthritis. Osteoarthritis Cartilage 2000 Jan;8(1):9-12.
5. Altman RD, Marcussen KC. Effects of ginger on knee pain in patients with osteoarthritis. Arthritis Rheum. 2001 Nov;44(11):2531-8.
6. Thomson M, Al-Qattan KK, Al-Sawan SM, Alnaqueeb MA, Khan I, Ali M. The use of ginger (Zingiber officinale Rosc.) as a potential anti-inflammatory and antithrombotic agent. Prostaglandins Leukot Essent Fatty Acids. 2002 Dec;67(6):475-8.
|Vitamin K2 Cuts Risk of Liver Cancer|
Nearly 8% of women with viral cirrhosis of the liver are at increased risk of developing liver cancer. Now Japanese scientists have discovered that vitamin K2 can significantly decrease their chances of developing liver cancer.
The study, published in the Journal of the American Medical Association, found that vitamin K2 decreases the risk of developing hepatocellular carcinoma in women with viral cirrhosis, possibly by delaying the onset of carcinogenesis.* The researchers recruited 40 women diagnosed with viral liver cirrhosis, of whom 21 were randomly assigned to treatment with 45 mg per day of vitamin K2. All of the patients received symptomatic therapy for ascites (the abnormal buildup of fluid in the abdominal cavity) and dietary advice.
During more than seven years of follow-up, the cumulative proportion of patients with hepatocellular carcinoma was significantly smaller in the treatment group (2 of 21 patients) compared to the control group (9 of 19 patients). All cases were newly diagnosed and in the initial stages of cancer. The annual incidence of hepatocellular carcinoma was 1.6% in the treated group, compared to 8.8% in the untreated group and 7.9% in the general cirrhotic population.
The researchers believe that geranylgeraniol—a side chain of vitamin K2—induces cell death in tumor cells, suggesting that geranylgeraniol might play an important role in inhibiting cell growth.
They wrote, “The study indicates that vitamin K2 decreases the risk of hepatocellular carcinoma to about 20% compared with the control group,” adding that these preliminary results should be confirmed in multicenter, randomized controlled trials.
* Habu D, Shiomi S, Tamori A, et al. Role of vitamin K2 in the development of hepatocellular carcinoma in women with viral cirrhosis of the liver. JAMA. 2004 Jul 21;292(3):358-