Lead induced oxidative stress: beneficial effects of Kombucha tea.

OBJECTIVE: To evaluate the effect of oral administration of Kombucha tea (K-tea) on lead induced oxidative stress. METHODS: Sprague Dawley rats were administered 1 mL of 3.8% lead acetate solution daily alone or in combination with K-tea orally for 45 d, and the antioxidant status and lipid peroxidation were evaluated. RESULTS: Oral administration of lead acetate to rats enhanced lipid peroxidation and release of creatine phosphokinase and decreased levels of reduced glutathione (GSH) and antioxidant enzymes (superoxide dismutase, SOD and glutathione peroxidase, GPx). Lead treatment did not alter humoral immunity, but inhibited DTH response when compared to the control. Lead administration also increased DNA fragmentation in liver. Oral administration of Kombucha tea to rats exposed to lead decreased lipid peroxidation and DNA damage with a concomitant increase in the reduced glutathione level and GPx activity. Kombucha tea supplementation relieved the lead induced immunosuppression to appreciable levels. CONCLUSION: The results suggest that K-tea has potent antioxidant and immunomodulating properties.

Role of selenium in reducing hypoxia-induced oxidative stress: an in vivo study.

At high altitudes, the reactive oxygen species are continuously generated as a consequence of low oxygen partial pressure (hypoxia), which causes tissue damage. The body's defence system to combat the oxidative stress (e.g., anti-oxidant enzymes, free radical scavengers such as vitamin C, vitamin E, beta-carotene, reduced glutathione and minerals such as selenium, etc.) may diminish. In the present study, the antioxidant effect of selenium (Se) in reducing the hypoxia-induced oxidative stress was evaluated by exposing male albino rats to hypoxic stress in a decompression chamber. Exposure to hypoxia resulted in an increase in malondialdehyde (MDA) levels in plasma and tissues and a concurrent decrease in blood glutathione (GSH), glutathione peroxidase (GPx), plasma protein and plasma selenium content when compared with controls. Haemoglobin concentration (Hb%), red blood corpuscles (RBC) and white blood corpuscles (WBC) count were also increased in the hypoxia-exposed group. Selenium supplementation to animals reversed the trend. There was a significant decrease (P < 0.001) in MDA and subsequent increase in plasma and tissue GSH levels. Similarly the blood and tissue GPx and plasma protein also increased significantly in the Se supplemented animals compared with control animals. The Hb%, RBC and WBC counts showed no significant difference between Se-fed and control rats. These results suggest that selenium may help in reducing the lipid peroxidation during hypoxia.

Antioxidant effect of beta-carotene on hypoxia induced oxidative stress in male albino rats.

Hypoxia is known to induce oxidative stress in organisms leading to tissue injury. In the present study beta-carotene (BC) given at 10 mg/kg body weight (BW) in reducing the oxidative stress induced by hypoxia was evaluated on male albino rats. Hypoxia exposure caused an increase in malondialdehyde (MDA) levels in plasma and tissues, a concurrent decrease in blood glutathione (GSH), glutathione peroxidase (GPx), plasma protein and plasma BC content. Hemoglobin concentration, Red blood corpuscles (RBC) and White blood corpuscles (WBC) count were also increased under hypoxia. BC supplementation reversed the trend, inducing a significant decrease (P<0.05) in MDA and subsequent increase in plasma and tissue GSH levels in animals exposed to hypoxia. Blood GPx and plasma protein also increased significantly in BC supplemented animals. BC supplementation did not alter the changes in Hb concentration, RBC and WBC count. BC has potent antioxidant activities in reducing the oxidative stress induced by hypobaric hypoxia.

Studies on toxicity, anti-stress and hepato-protective properties of Kombucha tea.

OBJECTIVE: The objective of the study was to evaluate toxicity, anti-stress activity and hepato-protective properties of Kombucha tea. METHOD: Kombucha tea was fed orally for 15 days using three different doses i.e. normal dose, five and ten times the dose. Rats were then sacrificed and various biochemical, and histological parameters were estimated. Anti-stress activity was evaluated either by 1) by exposing animals to cold and hypoxia and estimating the levels of malondialdehyde and reduced glutathione in plasma/blood or 2) by subjecting the animals to restraint stress and recording faecal output. Hepato-toxicity was induced by challenging the animals to an acute dose of paracetamol (1 gm/kg) orally and determining the plasma levels of SGPT, SGOT and MDA. RESULTS: The effect of oral administration of different doses of K-tea to albino rats was examined and the results indicate that K-tea has no significant toxicity as revealed by various biochemical and histopathological parameters. K-tea has been found to prevent lipid peroxidation and fall in reduced glutathione level when rats were exposed to cold and hypoxia in simulated chamber. Further, K-tea has also been found to decrease the Wrap-restraint faecal pellet output in rats. K-tea has also been found to decrease paracetamol induced hepatotoxicity significantly. CONCLUSION: The study shows that K-tea has anti-stress and hepato-protective activities.

Effect of vitamin E supplementation on hypoxia-induced oxidative damage in male albino rats.

BACKGROUND: There is growing evidence that free radicals mediated oxidative injury due to inadequate oxygen availability is an important factor in various pathologies at high altitude. Since vitamin E is known to protect the cells from oxidative damage due to its potent antioxidant properties, the present study was carried out to explore the effect of vitamin E supplementation on various hematological and biochemical parameters in hypoxia-induced oxidative stress in albino rats. METHODS: The experiments were conducted on male albino rats by intermittently exposing them to a simulated altitude of 7,576 m (25,000 ft), daily for 6 h for 15 d at 32 +/- 2 degrees C. The control group was fed vehicle only (1% Tween 80) and the experimental group was given vitamin E (40 mg per rat x d(-1)) orally, 5 d prior to and during the period of hypoxic exposure. The variables studied include: hemoglobin, hematocrit, RBC deformability index, alpha-tocopherol level, malondialdehyde (MDA), reduced glutathione (GSH), oxidized glutathione (GSSG), lactate dehydrogenase (LDH) and protein level in blood/plasma and various tissues. RESULTS: Significant increase in hematocrit and hemoglobin and decrease in RBC deformability index was observed on exposure to hypoxia while vitamin E supplementation maintained them at the normal level. Hypoxia led to the decrease in plasma vitamin E and blood glutathione (GSH) level and two-fold increase in the plasma malondialdehyde (MDA) level. Vitamin E supplementation, on the other hand, resulted in less of an increase in MDA and increased the GSH concentration significantly. LDH activity, which was elevated on exposure to hypoxia, was arrested on vitamin E supplementation. CONCLUSION: The results indicate that vitamin E supplementation results in preventing oxidative damage due to high altitude stress.

Effect of Kombucha tea on chromate(VI)-induced oxidative stress in albino rats.

The effect of Kombucha tea (KT) on oxidative stress induced changes in rats subjected to chromate treatment are reported. KT feeding alone did not show any significant change in malondialdehyde (MDA) and reduced glutathione (GSH) levels, but did enhance humoral response and delayed type of hypersensitivity (DTH) response appreciably over control animals. Chromate treatment significantly enhanced plasma and tissue MDA levels, decreased DTH response considerably, enhanced glutathione peroxidase and catalase activities; however, no change in GSH, superoxide dismutase and antibody titres was noticed. KT feeding completely reversed the chromate-induced changes. These results show that Kombucha tea has potent anti-oxidant and immunopotentiating activities.

Effect of hypobaric hypoxia on immune function in albino rats.

The effect of exposure to hypoxia on macrophage activity, lymphocyte function and oxidative stress was investigated. Hypoxia enhanced peritoneal macrophage activity as revealed by enhanced phagocytosis and free radical production. There was no significant change in antibody titres to sheep red blood cells in either serum or spleen during hypoxia. However, there was a considerable reduction in the delayed-type hypersensitivity response to sheep red blood cells, indicating the impairment of T-cell activity. Hypoxia decreased the blood glutathione (reduced) level and increased plasma malondialdehyde by a factor of about 2. It is therefore speculated that hypoxia imposes an oxidative stress leading to decreased T-cell acivity.

Neem oil--a fertility controlling agent in rhesus monkey.

Neem oil, an oil extracted from the seeds of Azadirachta indica has been found to act as a good spermicidal agent. Pre and post coital application of the oil intravaginally prevented pregnancy in rhesus monkey.

Antifertility activity of volatile fraction of neem oil.

NIM-76, the odorous and volatile fraction of neem oil, was investigated for its antifertility activity in vivo in rats, rabbits and rhesus monkeys. The drug is effective when applied before coitus but not so when applied during post-coital stages. It, therefore, appears to act mainly by its spermicidal effect. No alteration in the estradiol (E2) and progesterone (P) values was observed after the application of the drug in monkeys.

Contraceptive efficacy of Depot Provera jet-injected into the cervix.

Depot-medroxy progesterone acetate (DMPA) was jet deposited into the uterus/cervix of rats, rabbits and rhesus monkeys with the help of a modified jet injection apparatus. Since the drug was delivered under pressure, it was distributed deep into the muscular layers around the place of deposition. After one deposition the drug acted as an effective contraceptive for a period of three months. The merits of this delivery technique are discussed.

Volatile fraction of neem oil as a spermicide.

The volatile, odorous fraction of neem oil coded as NIM-76 obtained by steam distillation was investigated for in vitro spermicidal activity. The data showed that the minimum concentration which inhibited spermatozoal motility was 0.25 mg/ml for rat and 25 mg/ml for human spermatozoa. The effect of the drug on spermatozoal motility was found to be dose-dependent. The activity of this drug was not altered in the presence of vaginal or cervical mucus. Intra-vaginal application of NIM-76 in rabbits showed no irritation to the vaginal mucosa.

Effects of ascorbic acid supplementation on male reproductive system during exposure to hypoxia.

Two groups of male rats were exposed to simulated altitudes of 6060 m and 7576 m for 6 h/day for 7 days (intermittent exposure). In two additional groups of animals exposed to the same altitude, 100 mg of ascorbic acid (AA) was fed daily for 5 days prior to the exposure period and also during the exposure period. Rats that did not receive AA showed loss of body weight and weight of reproductive organs after exposure. Sex organs showed atrophy on histological examination and there was a deterioration in spermatozoal quality. There was an increase in alkaline and acid phosphatase, and decrease in protein, sialic acid and glyceryl phosphorylcholine content in various reproductive tissues after exposure. All the above changes in histology and biochemical composition could be partially prevented by AA supplementation. AA supplementation can therefore protect the male reproductive system from deleterious effects of hypoxia. The probable mechanism of action of AA is discussed.

Mechanism of antifertility action of neem oil.

PIP: The purpose of this study was to determine whether the antifertility effect of the antiestrogenic substance neem oil, extracted from the seeds of Azadirachta indica, acts directly on the uterus or through absorption from the vaginal epithelium into the general circulation. In 4 groups of rats the left uterine horn was ligated 2 days after coitus. Rats in group A were used as controls. In group B 25 mcl neem oil was administered intravaginally on days 2-4 with the animals in head down position for 3 minutes to ensure that the neem oil was uniformly distributed in the vagina. In group C the neem oil was administered on days 4-6, and in group D on days 7-9, i.e., after implantation. The ligatures were removed on day 12, and no viable implantation sites were found in either horn. The study showed that the neem oil exerts its effect on the endometrium through absorption into the general circulation from the vaginal epithelium. The antiestrogenic quality of neem oil explains its anti-implantation effect. But the postimplantation effect, which caused implanted fetuses to be either resorbed or expelled, may be due to direct toxicity, to a fall in progesterone level, or to interference with the uterine utilization of progesterone.^ieng

Copper iontophoresis in male contraception.

Copper was deposited by iontophoresis into vasa deferentia of animals, using 1 m. amp. current for 30-90 sec. in rat and 3 m. amp. current for 60 sec. in rabbits. The method was effective for a period of 9 months as a contraceptive. The effect of the metal was localised at the site of deposition and there was no effect on other reproductive organs. The mating behaviour and testosterone levels did not change. The utility of the technique in male contraception is discussed.

PIP: Results are presented of a study in which copper was deposited by iontophoresis into the vasa deferentia of 28 adult albino rats weighing over 300 gms and 14 rabbits weighing over 1.8 kg, to test the contraceptive effect. 7 rats were used as control, and 7 each were subjected to copper ionized for 30, 60, and 90 sec with a current of 1 m amp. 7 rabbits were controls and 7 were subjected to copper ionized for 60 sec with a current of 3 m amp. The animals were mated with fertile females between 20-30 days, 55-60 days, and 85-90 days after ionization. Rats were electro-ejaculated between 145-150 days after ionization and their spermatozoa tested for percent of live and dead counts. Further tests were done on termination of the study after 9 months. After ionization, there was no significant change in mean weight of the testicles, epididymis, or seminal vesicles in rabbits or rats but there was a significant reduction in vasal weight in rats. Spermatozoa sampled from the distal end of the vas deferens had a motility of 14% in the 30 sec group of rats, 9% in the 60 sec group, and 4% in the 90 sec group. 45% of spermatozoa beyond the ionization site were alive in the 30 sec group, 9% in the 60 sec group, and 7% in the 90 sec group. Spermatozoa from the same site survived for 10 minutes at 37 degrees Celsius in the 30 sec and 3 minutes in the 60 and 90 sec groups, compared to nearly 30 minutes for samples from the proximal end. In the rabbits, sperm motility was reduced to 8% below the point of ionization, only 8% of spermatozoa were alive, and at 37 degrees Celsius they survived for an average of 7 minutes. Mating experiments in ionized rats showed dead decapitated spermatozoa during successive matings up to 3 months and only a few living sperm in the semen after 5 months. Mating behaivor was not affected. The effect of the copper was localized at thesite of deposition. Copper iontophoresis appears to be a promising method for male contraception.