Life Extension Magazine®

November 1999 Medical Updates

Studies from around the world that can help you live longer.

Scientifically reviewed by: Dr. Gary Gonzalez, MD, in October 2024. Written by: Life Extension Editorial Staff.


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November 1999
Table Of Contents
 
  1. Male hormones and the risk of prostate cancer
  2. Melatonin levels, aging, and Alzheimer's disease
  3. Osteoporosis and intellectual disability: Is there any relation?
  4. Decreased tryptophan associated with brain lesions in the elderly
  5. Magnetic fields reduce melatonin concentrations in humans
  6. Free radical-scavenging activity of catechins
  7. Anti-inflammatory actions of cat's claw
  8. Deaths attributable to Alzheimer's disease in the United States
  9. Prevention of osteoporosis in corticosteroid treated postmenopausal women
  10. Effect of cocaine on cardiac biochemical functions
  11. Vitamin B complex for nocturnal leg cramps
  12. Endocrine aspects of aging in the male

  1. Male hormones and the risk of prostate cancer

    Full source: Cancer 1999 Jul 15;86(2):312-5

    It has been hypothesized that high androgen (male hormones) levels are determinants of prostate cancer. Serum concentrations of male hormones (i.e. testosterone, sex hormone-binding globulin (SHBG), and androstenedione) were analyzed to determine their role as predictors of prostate cancer between 1968 -1972 and stored at -20 degrees C. During a follow-up period of 24 years, a total of 166 prostate cancer cases occurred among men who originally were cancer free. Results showed no association between serum testosterone, SHBG, or androstenedione concentrations and the occurrence of subsequent prostate cancer. The results of the current study do not support the hypothesis that serum testosterone, SHBG, or androstenedione are causes of the later occurrence of prostate cancer.



  2. Melatonin levels, aging, and Alzheimer's disease

    Full source: Journal of Clinical Endocrinology and Metabolism, 1999, Vol 84, Iss 1, pp 323-327

    Sleep disruption, nightly restlessness, sun downing, and other circadian disturbances are frequently seen in Alzheimer's disease (AD) patients. Changes in the pineal gland are thought to be the biological basis for these behavioral disturbances. Melatonin is the main endocrine message for circadian rhythmicity from the pineal. This study sought to determine whether melatonin production was affected in 85 patients with AD (mean age, 75 years) and in 82 controls. After death, cerebrospinal fluid (CSF) was collected from AD patients and from control subjects without neurological or psychiatric disease. In old control subjects (over 80), CSF melatonin levels were half of those in control subjects of 41-80 [176 and 350 pg/mL, respectively]. In AD patients the CSF melatonin levels were only one fifth (55 pg/mL) of those in control subjects (273 pg/mL). In the present study, a dramatic decrease in the CSF melatonin levels was found in old control subjects and even more so in AD patients. Supplementation of melatonin may improve these behavioral disturbances in AD patients.



  3. Osteoporosis and intellectual disability: Is there any relation?

    Full source: Journal of Intellectual Disability Research, 1998, Vol 42, Part 5, pp 370-374

    One of the causes of osteoporosis is immobility. The present study examined osteoporosis in 23 bedridden adults with intellectual disability. It was found that the bone mineral density of the subjects was low, even though their calcium intake was more than adequate. Vertebral and other fractures were concentrated mainly in the elderly subjects over 50 years old. Very low vitamin D levels were also found in the subjects despite good nutritional levels. It is concluded that people with intellectual disability and mobility disorders are at risk of metabolic bone disease.



  4. Decreased tryptophan associated with brain lesions in the elderly

    Full source: Journal of Neurology Neurosurgery and Psychiatry, 1999, Vol 66, Iss 1, pp 100-103

    The aim was to identify potentially treatable risk factors for cerebral white matter lesions often found on MRI in elderly persons. This study consisted of 178 subjects aged 60 years or older. Brain MRI infarcts, deep white matter lesions (DWMLs), and periventricular hyperintensities were found in 26%, 43%, and 29% of the 178 participants, respectively. Subjects with DWMLs were significantly older and had lower blood concentrations of tryptophan, including higher frequency of hypertension, higher systolic blood pressure, and more brain infarcts. Greater age and lower blood tryptophan concentrations were independently associated with DWMLs. When tryptophan concentrations were low, the brain lesions grading was higher, and visa versa. Hypertension and brain infarction were more common in subjects with higher extents of DWMLs. The present study suggests that greater age and lower blood tryptophan concentrations were important in producing DWMLs in elderly subjects.



  5. Magnetic fields reduce melatonin concentrations in humans

    Full source: Journal of Pineal Research, 1998, Vol 25, Iss 4, pp 240-244

    Daytime rhythm of blood melatonin concentrations was estimated in 12 men with low back pain syndrome before and after exposure to a very low-frequency magnetic field (2.9 mT, 40 Hz, square wave, bipolar). Patients were exposed to the magnetic field for 3 weeks (20 min per day, 5 days per week) either in at 10:00 am or at 6:00 pm. Significant depression in nocturnal melatonin rise was observed regardless of the time of exposure. This phenomenon was characteristic for all the subjects. The percent of inhibition of melatonin secretion varied among the studied individuals.



  6. Free radical-scavenging activity of catechins

    Full source: Phytochemistry, 1998, Vol 49, Iss 8, pp 2379-2382

    The minimum concentrations of catechins sufficient to rescue the E. Coli bacteria from death due to artificially generated free radicals were found to be 70 mu M for (-)-epicatechingallate, 100 mu M for (-)-epicatechin and 125 mu M for (+)-catechin. These values were comparable with the value of vitamin E, a typical free radical scavenger. On the other hand, vitamin C and beta-carotene showed about one tenth the scavenging activity of catechins. No scavenging activity was found for superoxide dismutase even at 86 mM. These facts indicate that catechins have high free radical scavenging activity.



  7. Anti-inflammatory actions of cat's claw

    Full source: Alimentary Pharmacology & Therapeutics, 1998, Vol 12, Iss 12, pp 1279-1289

    Uncaria tomentosa is a vine commonly known as cat's claw and is used in traditional Peruvian medicine for the treatment of a wide range of health problems, particularly digestive complaints and arthritis. In this study, the proposed anti-inflammatory properties of cat's claw was investigated. Specifically, does cat's claw extract protect against oxygen-induced stress? Cat's claw, in the amount of 100 mu g/mL inhibited the induced epithelial and macrophage (immune cell) cell death, nitrite formation, the activation of NF-kappa B, and markedly weakened indomethacin-enteritis. Thus, cat's claw protects cells against oxidative stress and negates the activation of NF-kappa B. These studies provide evidence for the widely held belief that cat's claw is an effective anti-inflammatory agent.



  8. Deaths attributable to Alzheimer's disease in the United States

    Full source: American Journal of Public Health, 1999, Vol 89, Iss 1, pp 90-92

    This study provided 2 estimates of the number of deaths attributable to Alzheimer's disease in the United States. One estimate was based on data from the East Boston, Massachusetts study. The second was based on a simulation using population-based estimates of prevalence and separate estimates of excess death by duration of disease. Despite different methods and very different estimates of prevalence, these 2 methods led to very similar estimates of 173,000 and 163,000 deaths. These estimates suggest that 7.1% of all deaths in the United States in 1995 were attributable to Alzheimer's disease, placing it on a par with cerebrovascular diseases as the third leading cause of death.



  9. Prevention of osteoporosis in corticosteroid treated postmenopausal women

    Full source: Annals of the Rheumatic Diseases, 1998, Vol 57, Iss 12, pp 724-727

    This study compared cyclic etidronate and a placebo during two years in 37 postmenopausal women receiving long term corticosteroid treatment, mainly for polymyalgia rheumatica (40% of the patients) and rheumatoid arthritis (30%). Bone density was measured in the lumbar spine, femoral neck, and femoral trochanter. After two years of treatment there was a significant percentage increase in bone density in the etidronate treated group. The estimated treatment difference was 9.3%. Etidronate increased bone density in the spine 4.9% whereas the placebo group lost bone (-2.4%). At the femoral neck there as an estimated difference of 5.3% between the groups (etidronate: 3.6%; placebo group: -2.4%). The estimated difference at the trochanter was 8.2% (etidronate: 9.0%, placebo: 0.5%). No significant bone loss occurred in the hip in placebo treated patients. Cyclic etidronate is an effective treatment for postmenopausal women receiving corticosteroid treatment and is well tolerated.



  10. Effect of cocaine on cardiac biochemical functions

    Full source: Journal of Cardiovascular Pharmacology, 1999, Vol 33, Iss 1, pp 1-6

    The role of cocaine in cardiac ischemia (obstruction of blood supply) and subsequent reversible and irreversible pathologic changes is well established. Nevertheless, the mechanisms leading to cardiac injury and irreversible cellular changes remain elusive. Free radicals are the critical mediators of cellular damage during ischemia-reperfusion. This study explored the response of cardiac oxidative stress parameters to intravenous (i.v.) and intraperitoneal (i.p.) cocaine exposure. Repeated cocaine exposure produced significant impairment in cardiac integrity, demonstrated by increased circulating lactate (2.4-fold;), creatine kinase (2.2-fold;), and creatinine levels (1.7-fold). Infiltration of neutrophils (immune cells) into myocardial cavities also was evident. Intravenous cocaine administration also had negative effects on cardiac oxidative stress measures. In conclusion, the data indicate that cocaine administration compromised the heart's antioxidant defense system.



  11. Vitamin B complex for nocturnal leg cramps

    Full source: Journal of Clinical Pharmacology, 1998, Vol 38, Iss 12, pp 1151-1154

    Nocturnal leg cramps is a common and troublesome problem in elderly individuals, and their cause is unknown. Treatment with quinine is a common practice, but the effectiveness of the drug is doubtful and adverse drug effects are common. This study evaluated the safety and efficacy of vitamin B complex capsules (fursulthiamine 50 mg hydroxocobalamin 250 mu g, pyridoxal phosphate 30 mg, and riboflavin 5 mg) in 28 elderly patients with hypertension who had severe nocturnal leg cramps that disturbed their sleep. Both the patients taking vitamin B capsules and those taking placebo received medications three times daily. After 3 months, 86% of the patients taking vitamin B had prominent remission of leg cramps, whereas those taking placebo had no significant difference from baseline. Treatment with vitamin B complex significantly reduced the frequency, intensity and duration of nocturnal leg cramps. Because quinine is not without potential for side effects, and vitamin B complex is a relatively safe and effective alternative, clinicians should reconsider the treatment of choice for nocturnal leg cramps.



  12. Endocrine aspects of aging in the male

    Full source: Molecular and Cellular Endocrinology, 1998, Vol 145, Iss 1-2, pp 153-159

    There is a statistical decline of testosterone levels in aging men, mostly in free testosterone. This fall is moderate, but aging men also show clinical signs of hypogonadism (loss of muscle mass/strength, reduction in bone mass and an increase in body fat). This might represent not only a fall but also an impairment of the biological action of androgens in targeted organs. The first small scale studies of androgen supplement administration in aging men were not disappointing. Anticipated risks lie with the prostate and the cardiovascular system. However, according to the article, the risks with regard to prostate disease are often over-rated. The question remains how to identify the segment of the aging male population that would possibly benefit from androgen supplements. For the treatment of postmenopausal women, 'designer oestrogens' are being developed. Similarly, designer androgens retaining beneficial anabolic effects with elimination of harmful effects on the prostate and cardiovascular system could be devised.