Comparative effects of acute and subacute lycopene administration on chromosomal aberrations induced by cisplatin in male rats

Lycopene is a natural carotenoid, free radical scavenger, and presents protective effects by inhibiting oxidative DNA damage. The objective of the current study was to investigate the cytogenetic effects of a single acute and four daily gavage administrations of lycopene, and to examine possible protective effects on chromosomal damage induced by the antitumor drug cisplatin (cDDP) in rat bone marrow cells. The animals were divided into treatment groups, with three lycopene doses in the acute treatment (2, 4, and 6 mg/kg b.w.), three lycopene doses in the subacute treatment (0.5, 1.0, and 1.5 mg/kg b.w.) with and without cDDP (5 mg/kg b.w. i.p.), and respective controls. The results indicated that lycopene is neither cytotoxic nor clastogenic when compared with the negative controls (P > 0.01). cDDP-treated animals submitted to acute and subacute treatments with different lycopene doses showed a significant reduction (p < 0.01) in the number of abnormal metaphases when compared with the animals treated only with cDDP. The protective effects of lycopene on cDDP-induced chromosomal damage may be attributed to its antioxidant activity. These results suggest that this carotenoid may prove useful in reducing some of the toxic effects associated with certain classes of chemotherapeutic agents. (c) 2006 Elsevier Ltd. All rights reserved.

Pancreas damage and intratracheal NiCl2 administration. Effects of nickel chloride.

Changes in activities of Cu-Zn superoxide dismutase (SOD- E.C.1.15.1.1.) and lactate dehydrogenase (LDH- E.C.1.1.1.27.) and levels of copper, total protein, triglycerides, phospholipids and total lipids were investigated in pancreas of rats after intratracheal administration of NiCl2 (8.4 mumol/kg). Nickel chloride induced increased SOD activity in pancreas and erythrocytes. This elevation was related to increased copper and decreased phospholipid content in pancreas of these animals. In conclusion, the ability of an animal to tolerate nickel chloride induced damage was governed by a delicate balance between the generation of cytotoxic agents and the various pancreas defense capabilities.

Toxicologic evaluation of acute and subacute oral administration of Cucurbita maxima seed extracts to rats and swine

The extract prepared from dried seeds of Cucurbita maxima was administered to rats and pigs. Following a single dose or 4 weeks of daily oral administration, the extract produced no changes in serum glucose, urea, creatinine, total protein, uric acid, GOT, GPT, LDH or blood counts. Urine analysis (urea, uric acid, creatinine, total protein, Na and K), as well as histopathological investigation, showed no abnormalities. These results taken as a whole indicate that the seeds of C. maxima as used in Brazilian folk medicine are not toxic for rats and swine.

Relationship between ethanol and sucrose self-administration and schedule-induced polydipsia

Studies have suggested a relationship between drug abuse and compulsive behaviors. The present experiments investigated the relationship between schedule-induced polydipsia (SIP) and self-administration (SA) of ethanol and sucrose. SIP served as a model of compulsive behavior. and oral self-administration on a progressive-ratio (PR) schedule of reinforcement assessed the reinforcing value of either a 10% ethanol solution or an isocaloric sucrose solution. Rats first were exposed to PR sessions in which break points were the dependent variable and then switched to SIP sessions. with number of licks as the dependent variable. Results showed a positive relationship between PR and SIP for sucrose but not for ethanol: higher and lower PRs for sucrose were associated with higher and lower SIP levels. The order of the sessions then was reversed, such that SIP sessions were run before PR sessions. An opposite relationship was observed in which high and low SIP animals exhibited low and high PR break points, respectively. The relationship between SIP and SA was dependent on the reinforcing value of the substance and on prior SIP exposure. These results may reflect a common dopaminergic substrate and suggest that prior experience in coping with stress may reduce vulnerability to substance abuse behavior. (c) 2008 Published by Elsevier Inc.

Alcohol, Drug Abuse, and Mental Health Administration research programs.

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