Combined cerium and zinc oxide nanoparticles induced hepato-renal damage in rats through oxidative stress mediated inflammation.

The toxicity profiles of nanoparticles (NPs) used in appliances nowadays remains unknown. In this study, we investigated the toxicological consequences of exposure to cerium oxide (CeO2) and zinc oxide (ZnO) nanoparticles given singly or in combination on the integrity of liver and kidney of male Wistar rats. Twenty (20) rats were allotted into four groups and treated as: Control (normal saline), CeO2NPs (50 µg/kg), ZnONPs (80 µg/kg) and [CeO2NPs (50 µg/kg) + ZnONPs (80 µg/kg)]. The nanoparticles were given to the animals through the intraperitoneal route, three times per week for four repeated weeks. Results revealed that CeO2 and ZnO NPs (singly) increased serum AST and ALT by 29% & 57%; 41% & 18%, and co-administration by 53% and 23%, respectively. CeO2 and ZnO NPs increased hepatic and renal malondialdehyde (MDA) by 33% and 30%; 38% and 67%, respectively, while co-administration increased hepatic and renal MDA by 43% and 40%, respectively. The combined NPs increased hepatic NO by 28%. Also, CeO2 and ZnO NPs, and combined increased BAX, interleukin-1ß and TNF-α by 45, 38, 52%; 47, 23, 82% and 41, 83, 70%, respectively. Histology revealed hepatic necrosis and renal haemorrhagic parenchymal in NPs-treated rats. Summarily, CeO2 and ZnO NPs produced oxidative injury and induced inflammatory process in the liver and kidney of experimental animals.

Hexane fraction of Annona muricata (Sour sop) seed ameliorates testosterone-induced benign prostatic hyperplasia in rats.

BACKGROUND: Annona muricata is used in traditional African medicine to manage urinary obstruction. In this study, we hypothesized that hexane fraction of Annona muricata (HFAM) seeds will ameliorate testosterone propionate (Tp)-induced benign prostatic hyperplasia (BPh). METHODS: Castrated rats were assigned into six groups: non-castrated control, castrated control, castrated rats that received Tp (BPh group), [BPh+HFAM], [BPh+HFAM + finasteride], [BPh + finasteride]. RESULTS: The BPh rats had 3.8 and 3.9 folds increases in prostatic and organo-somatic weight, while treatment with HFAM alone and [HFAM + finasteride] decreased prostatic weight by 22% and 34%, respectively. BPh increased the activities of serum and prostatic total acid phosphatase by 95% and 121%; and activities of serum and prostatic alkaline phosphatase by 54% and 281%, respectively. Serum and prostatic lipid peroxidation were increased by 44% and 82%, respectively, in BPh rats with a concomitant decrease in prostatic superoxide dismutase by 73%. In BPh rats, serum and prostatic myeloperoxidase increased by 4.0 and 2.0 folds, while serum nitric oxide increased by 2.4 folds, respectively. Strong expression of inducible nitric oxide synthase, Bcl2, beta-catenin, androgen and estrogen receptors were observed in BPh rats. Importantly, treatment with HFAM or finasteride (or combination) attenuated prostatic weight, inflammatory and antioxidant indices in BPh rats. CONCLUSION: HFAM may serve as novel therapeutic agent against BPh.

Enhanced production of succinic acid from methanol-organosolv pretreated Strophanthus preussii by recombinant Escherichia coli.

A biorefinery process for high yield production of succinic acid from biomass sugars was investigated using recombinant Escherichia coli. The major problem been addressed is utilization of waste biomass for the production of succinic acid using metabolic engineering strategy. Here, methanol extract of Strophanthus preussii was used for fermentation. The process parameters were optimized. Glucose (9 g/L), galactose (4 g/L), xylose (6 g/L) and arabinose (0.5 g/L) were the major sugars present in the methanol extract of S. preussii. E. coli K3OS with overexpression of soluble nucleotide pyridine transhydrogenase sthA and mutation of lactate dehydrogenase A (ldhA), phosphotransacetylase acetate kinase A (pta-ackA), pyruvate formate lyase B (pflB), pyruvate oxidase B (poxB), produced a final succinic acid concentration of 14.40 g/L and yield of 1.10 mol/mol total sugars after 72 h dual-phase fermentation in M9 medium. Here, we show that the maximum theoretical yield using methanol extracts of S. preussii was 64%. Hence, methanol extract of S. preussii could be used for the production of biochemicals such as succinate, malate and pyruvate.

Methyl jasmonate reduces testosterone-induced benign prostatic hyperplasia through regulation of inflammatory and apoptotic processes in rats.

BACKGROUND: Phytotherapy is becoming a treatment option in management of diseases including benign prostatic hyperplasia (BPH). We have shown previously that methyl jasmonate (MeJA) ameliorated BPH, however the underlying mechanism of action remains unknown. This study was designed to investigate in mechanistic terms the protective role of MeJA in BPH. METHODS: BPH was induced by daily injections of testosterone propionate (TP) (3mg/kg) for 28 days. RESULTS: The weight and organo-somatic weight of prostate in BPH rats were 6.8 and 5.1 times higher than castrated-control group, respectively. Inflammatory markers; prostatic myeloperoxidase and total nitric oxide were significantly increased in BPH group. The activity of aniline hydroxylase (Phase I drug metabolizing enzyme) was significantly increased in BPH rats by 22%. In BPH group, immuno-histochemistry revealed strong expression of prostatic inducible nitric oxide synthase, cyclooxygenase-2 and Bcl2, while mild expression of p53 and Bax were seen. Serum triglyceride and total cholesterol were significantly increased, while HDL-c was decreased in BPH. Interestingly, MeJA and finasteride (singly or combination) attenuated inflammatory indices and induced apoptotic parameters in BPH rats. CONCLUSION: MeJA protects against TP-induced BPH via mechanisms that involve anti-inflammation, induction of apoptosis and inhibition of phase I drug metabolizing enzyme.

Antioxidant and antiproliferative potentials of methanol extract of Xylopia aethiopica (Dunal) A. Rich in PC-3 and LNCaP cells.

BACKGROUND: Our previous studies showed that fruit methanol extract from Xylopia aethiopica (MEXA) exhibited antiproliferative activity in human cervical cancer cells via the induction of apoptosis. The present study was designed to assess the antiproliferative, antiangiogenic and antioxidant effects of MEXA on prostate cancer (PCa) cells (PC-3 and LNCaP). METHODS: PC-3 and LNCaP cells were cultured and treated with MEXA (10, 50 and 100 µg/mL). The sodium 3'-[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis (4-methoxy-6-nitro) benzene sulfonic acid hydrate (XTT) and lactate dehydrogenase (LDH) assays were used to evaluate cell viability and cytotoxicity, respectively. DNA fragmentation was determined by cell death detection ELISA plus, and angiogenesis was assessed by chicken chorioallantoic membrane (CAM) assay. The antioxidant activities of MEXA were determined by DPPH and hydroxyl (OH) radicals' scavenging methods as well as through the inhibition of lipid peroxidation (LPO) in rats' liver homogenate. RESULTS: MEXA at 100, 250 and 500 µg/mL scavenged DPPH by 48%, 62%, 70% and OH radical by 39%, 58%, 67%, respectively. MEXA significantly (p<0.05) inhibited LPO in a concentration-dependent manner. In addition, MEXA had antiproliferative effects on PC-3 and LNCaP with IC50 of 62.1 and 73.6 µg/mL, respectively, at 96 h. The LDH assay showed that MEXA had low toxicity in vitro at its IC50 values. The extent of DNA fragmentation by MEXA showed higher values in PC-3 and LNCaP, suggesting the possible induction of apoptosis. In contrast, MEXA did not affect the network of vessels in CAM, thus lacking anti-angiogenic property. CONCLUSIONS: These findings suggest that MEXA induces antiproliferative activity in PCa cells through a mechanism that involves apoptosis. Therefore, MEXA may be a potential therapeutic agent for PCa.

Methyl Jasmonate Ameliorates Testosterone Propionate-induced Prostatic Hyperplasia in Castrated Wistar Rats.

Benign prostate hyperplasia (BPH) is a progressive disease that is related to age. Known therapeutic agents used in the treatment of BPH are associated with toxicity. Therefore, chemoprevention could be an effective approach. We investigated the ameliorative effects of methyl jasmonate (MeJA) in testosterone propionate (TP)-induced BPH in castrated rats. Castration was performed by removing both testes through the scrotum sack under ketamine anesthesia. Rats were assigned into seven groups of seven animals each: non-castrated control, castrated control, castrated rats that received TP, castrated rats that received TP and MeJA, castrated rats that received TP and finasteride, castrated rats that received MeJA, and castrated rats that received finasteride. Results indicate that BPH rats had significantly (p < 0.05) elevated prostate weight and relative weight of prostate relative to control. Also, BPH rats had significantly (p < 0.05) increased activities of prostatic acid and alkaline phosphatases, levels of zinc, and malondialdehyde. Further, levels of enzymic and non-enzymic antioxidative indices were significantly (p < 0.05) reduced in BPH. Histology of prostate revealed hyperplasia of transition lobe, increased expression of PSA, and Ki67 in BPH. Treatment with MeJA and finasteride attenuated the activities of the phosphatases and levels of antioxidants in BPH. Overall, MeJA ameliorates BPH via antioxidative mechanism. Copyright © 2017 John Wiley & Sons, Ltd.

Developing a competency-based medical education curriculum for the core basic medical sciences in an African Medical School.

The College of Medicine of the University of Ibadan recently revised its MBBS and BDS curricula to a competency-based medical education method of instruction. This paper reports the process of revising the methods of instruction and assessment in the core basic medical sciences directed at producing medical and dental graduates with a sound knowledge of the subjects sufficient for medical and dental practice and for future postgraduate efforts in the field or related disciplines. The health needs of the community and views of stakeholders in the Ibadan medical and dental schools were determined, and the "old" curriculum was reviewed. This process was directed at identifying the strengths and weaknesses of the old curricula and the newer competences required for modern-day medical/dental practice. The admission criteria and processes and the learning methods of the students were also studied. At the end of the review, an integrated, system-based, community-oriented, person-centered, and competency-driven curriculum was produced and approved for implementation. Four sets of students have been admitted into the curriculum. There have been challenges to the implementation process, but these have been overcome by continuous faculty development and reorientation programs for the nonteaching staff and students. Two sets of students have crossed over to the clinical school, and the consensus among the clinical teachers is that their knowledge and application of the basic medical sciences are satisfactory. The Ibadan medical and dental schools are implementing their competency-based medical education curricula successfully. The modifications to the teaching and assessment of the core basic medical science subjects have resulted in improved learning and performance at the final examinations.

Efficient production of succinic acid from Palmaria palmata hydrolysate by metabolically engineered Escherichia coli.

Succinic acid, a C4 dicarboxylic acid is used in many fields such as food, agriculture, pharmaceutical and polymer industries. In this study, microbial production of succinic acid from Palmaria palmata was investigated for the first time. In engineered Escherichia coli KLPPP, lactate dehydrogenase, pyruvate formate lyase, phosphotransacetylase-acetate kinase and pyruvate oxidase genes were deleted while phosphoenolpyruvate carboxykinase was overexpressed. The recombinant exhibited higher molar yield of succinic acid on galactose (1.20±0.02mol/mol) than glucose (0.48±0.03mol/mol). The concentration and molar yield of succinic acid were 22.40±0.12g/L and 1.13±0.02mol/mol total sugar respectively after 72h dual phase fermentation from P. palmata hydrolysate which composed of glucose (12.57±0.17g/L) and galactose (18.03±0.10g/L). The results demonstrate that P. palmata red macroalgae biomass represents a novel and an economically alternative feedstock for biochemicals production.

Ameliorative Effects of Chloroform Fraction of Cocos nucifera L. Husk Fiber Against Cisplatin-induced Toxicity in Rats.

BACKGROUND: Cisplatin (Cis) is used in the treatment of solid tumors and is known to elicit serious side effects. OBJECTIVE: The present study investigated the protective effects of chloroform fraction of Cocos nucifera husk fiber (CFCN) against Cis-induced organs' damage and chromosomal defect in rats. Quercetin (QUE), standard antioxidant, served as positive control. MATERIALS AND METHODS: Thirty male Wistar rats were assigned into six groups and treated with corn oil (control), Cis alone, Cis + CFCN, CFCN alone, Cis + QUE, and QUE alone. QUE and CFCN were given at 50 and 200 mg/kg/day, respectively, by oral gavage for 7 days before the rats were exposed to a single dose of Cis (10 mg/kg, intraperitoneal) at the last 36 h of study. RESULTS: Administration of Cis alone caused a significant (P < 0.05) increase in the levels of serum creatinine and urea by 72% and 70%, respectively, when compared with the control. The activity of serum aspartate aminotransferase was significantly (P < 0.05) increased while alanine aminotransferase and alkaline phosphatase were insignificantly (P > 0.05) affected in Cis-treated rats. Furthermore, the activities of hepatic and renal catalase, superoxide dismutase, glutathione S-transferase, glutathione peroxidase, and levels of reduced glutathione were significantly (P < 0.05) decreased in Cis-treated rats with concomitant elevation of malondialdehyde. Cis exposure increased the frequency of micro nucleated polychromatic erythrocytes (mPCE) by 92%. Pretreatment with CFCN inhibited lipid peroxidation, enhanced the activities of some antioxidative enzymes and reduced the frequency of mPCE. CONCLUSIONS: Chloroform fraction of CFCN may protect against organs damage by Cis. Further studies are required to determine the component of the plant responsible for this activity. SUMMARY: Cisplatin (Cis) is used in the treatment of solid tumors and is known to elicit serious side effects. This study investigated the protective effects of chloroform fraction of Cocos nucifera husk fiber (CFCN) against Cis-induced organs' damage while quercetin (QUE) served as standard antioxidant.Thirty male Wistar rats were assigned into six groups and treated with corn oil (Control), Cis alone, Cis + CFCN, CFCN alone, Cis + QUE and QUE alone.QUE and CFCN were given at 50 and 200 mg/kg/day respectively by oral gavage for seven days before the rats were exposed to a single dose of Cis (10mg/kg, i.p.) at the last 36 h of study. Results indicate that administration of Cis caused a significant (P<0.05) increase in the levels of serum creatinine and urea by 72% and 70% respectively.The activity of serum aspartate aminotransferase was significantly (P <0.05) increased while alanine aminotransferase and alkaline phosphatase were insignificantly (P>0.05) affected in Cis-treated rats.The activities of hepatic and renal catalase, superoxide dismutase, glutathione-s-transferase, glutathione peroxidase and levels of reduced glutathione were significantly (P<0.05) decreased in Cis-treated rats with concomitant elevation of malondialdehyde.Cis exposure increased the frequency of micronucleated polychromatic erythrocytes (mPCE) by 92%.Pretreatment with CFCN inhibited lipid peroxidation, enhanced the activities of some antioxidative enzymes and reduced the frequency of mPCE. The findings suggest that CFCN may protect against organs damage by cisplatin.Further studies are required to determine the component of the plant responsible for this activity.

Modulatory effects of methanol extract of Artocarpus altilis (Moraceae) on cadmium-induced hepatic and renal toxicity in male Wistar rats.

BACKGROUND: Cadmium (Cd) is an environmental risk factor with an established toxicity in animals. Therefore, natural antioxidants may be protective against Cd-toxicity. The study was designed to investigate the modulatory effects of methanol extract of Artocarpus altilis (AA) on oxidant-antioxidant balance and lipid profile in liver and kidney of Cd-exposed rats while quercetin (QE) served as standard. METHODS: Total phenolic content (TPC) and 2,2-diphenyl-1-picryldydrazyl (DPPH) radical scavenging activity of AA were assessed in vitro. In vivo, rats were orally treated with AA (200mg/kg) and QE (25mg/kg) daily for three weeks and challenged with two doses of Cd (1.5mg/kg, i.p.) in the last 72h. RESULTS: The TPC and DPPH scavenging effects of AA were high and comparable with catechin. Cd-intoxication significantly (p<0.05) increased the activities of serum alanine aminotransferase and levels of urea, total bilirubin and creatinine by 94%, 60%, 234% and 76%, respectively. Cd-exposure caused a significant increase (p<0.05) in serum and tissues total cholesterol, triglyceride, low-density lipoprotein-cholesterol and reduction in high-density lipoprotein-cholesterol levels. The levels of hepatic and renal antioxidant parameters: glutathione-s-transferase, superoxide dismutase and reduced glutathione were significantly (p<0.05) decreased in Cd-intoxicated rats with concomitant elevation of lipid peroxidation. Histopathological findings revealed necrosis and distortion of architecture of renal tissue and, periportal infiltration in hepatocytes of Cd-intoxicated rats. Pretreatment with AA and QE restored antioxidant status, lipid profile and attenuated the lesions in the tissues. CONCLUSIONS: Extract of A. altilis protects against Cd-induced liver and kidney dysfunction via antioxidant and radical scavenging activities.

Kolaviron, a biflavonoid fraction from Garcinia kola, protects against isoproterenol-induced injury by mitigating cardiac dysfunction and oxidative stress in rats.

BACKGROUND: The aim of this study was to evaluate the cardioprotective effects of kolaviron (KV), a biflavonoid from Garcinia kola seeds, in rats intoxicated with isoproterenol chloride (ISO) while quercetin (QUE) served as standard. METHODS: Forty-two male Wistar rats (180-200 g) were randomly divided into seven groups of six rats each. Group 1 served as control; group 2 received ISO (85 mg/kg subcutaneously); groups 3, 4 and 5 received ISO and KV1 [100 mg/kg orally (p.o.)], KV2 (200 mg/kg, p.o.) and QUE (25 mg/kg, p.o.), respectively; and groups 6 and 7 received QUE and KV2, respectively. RESULTS: Administration of ISO caused significant (p<0.05) elevation of serum creatine phosphokinase, lactate dehydrogenase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase by 2.2-, 1.9-, 2.1-, 1.9- and 1.7-fold, respectively, relative to controls, with a concomitant decrease in cardiac activities of these enzymes. Administration of ISO led to significant decrease (p<0.05) in the levels of cardiac superoxide dismutase, catalase, glutathione S-transferase, reduced glutathione and increase in malondialdehyde (MDA). Also, ISO-treated rats had significantly higher values of serum total cholesterol, triglycerides and low-density lipoprotein cholesterol relative to controls. Supplementation with KV2 and QUE caused significant elevation of cardiac antioxidant enzymes, normalized the marker enzymes and reduced MDA levels. CONCLUSIONS: KV protects against ISO-induced cardiotoxicity in vivo, suggesting its usefulness as a possible chemoprophylactic agent against cardiotoxic drugs.

In vitro studies to assess the antioxidative, radical scavenging and arginase inhibitory potentials of extracts from Artocarpus altilis, Ficus exasperate and Kigelia africana.

OBJECTIVE: To justify the use of Artocarpus altilis (A. altilis), Ficus exasperata (F. exasperata) and Kigelia africana (K. africana) in ethnomedicine for the treatment of several ailments and to evaluate the in vitro antioxidant, radical scavenging and arginase inhibitory potentials of these herbs and compared with catechin (Standard). METHODS: Antioxidant activities were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide, hydrogen peroxide (H2O2) and hydroxyl (OH) radicals scavenging methods. The flavonoids and phenolics content, inhibition of arginase activity, Fe(2+)/ascorbate-induced lipid peroxidation (LPO) and reducing power were also determined. RESULTS: The A. altilis, F. exasperata and K. africana showed dose-dependent and significant scavenging of DPPH, H2O2 and OH radicals in vitro relative to catechin. The A. altilis and F. exasperata effectively scavenged DPPH radical with IC50 of 593 and 635 µg/mL and, OH radical with IC50 of 487 and 514 µg/mL, respectively. The DPPH and OH radicals scavenging activities followed the order A. altilis>F. exasperata>K. africana. In addition, A. altilis and F. exasperata significantly (P<0.05) inhibited LPO in a dose-dependent manner. The A. altilis extract had the most potent inhibitory activity against LPO with 79% relative to catechin (28%) at 750 µg/mL. The reducing power followed the order: A. altilis>Catechin>F. exasperata>K. africana at 1 000 µg/mL. The A. altilis at 500 and 750 µg/mL significantly (P<0.05) inhibited arginase activity by 63% and 67%, respectively. The flavonoids contents were found to be highest in A. altilis. CONCLUSIONS: Extracts of A. altilis and F. exasperata are potent antioxidative agents with strong radical scavenging activity and inhibition of lipid peroxidation.

Effects of Methanol Extract of Breadfruit (Artocarpus altilis) on Atherogenic Indices and Redox Status of Cellular System of Hypercholesterolemic Male Rats.

We investigated the effects of methanol extract of Artocarpus altilis (AA) on atherogenic indices and redox status of cellular system of rats fed with dietary cholesterol while Questran (QUE) served as standard. Biochemical indices such as total cholesterol (TC), triglycerides (TG), low- and high-density lipoproteins-cholesterol (LDL-C and HDL-C), aspartate and alanine aminotransferases (AST and ALT), lactate dehydrogenase (LDH), reduced glutathione, glutathione-s-transferase, glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD), and lipid peroxidation (LPO) were assessed. Hypercholesterolemic (HC) rats had significantly increased relative weight of liver and heart. Dietary cholesterol caused a significant increase (P < 0.05) in the levels of serum, hepatic, and cardiac TC by 110%, 70%, and 85%, LDL-C by 79%, 82%, and 176%, and TG by 68%, 96%, and 62%, respectively. Treatment with AA significantly reduced the relative weight of the organs and lipid parameters. There were beneficial increases in serum and cardiac HDL-C levels in HC rats treated with AA. In HC rats, serum LDH, ALT, and AST activities and levels of LPO were increased, whereas hepatic and cardiac SOD, CAT, and GPx were reduced. All biochemical and histological alterations were ameliorated upon treatment with AA. Extract of AA had protective effects against dietary cholesterol-induced hypercholesterolemia.

Effect of tenofovir, an antiretroviral drug, on hepatic and renal functional indices of Wistar rats: protective role of vitamin E.

BACKGROUND: Tenofovir (TFR) is a nucleotide reverse transcriptase inhibitor with activity against human immunodeficiency virus. We studied the effect of TFR administered to Wistar rats on hepatic and renal function markers and the possible modulatory role of vitamin E (Vit E). METHODS: The study consists of four groups of six rats each. The first group served as control, the second group received TFR at 50 mg/kg/day for 4 weeks, third group received TFR and Vit E, and the last group received Vit E alone. RESULTS: TFR administration caused a significant (p<0.05) increase in the levels of serum urea, creatinine, urinary glucose, and protein by 65%, 51%, 88%, and 79%, respectively, relative to controls. This was followed by a significant (p<0.05) reduction in creatinine clearance of TFR-treated rats. There were no significant differences (p>0.05) in the activities of serum aminotransferases, γ-glutamyltransferase, and alkaline phosphatase in TRF-treated rats relative to controls. TFR administration caused a marked elevation of malondialdehyde (MDA; index of lipid peroxidation) in the animals. Specifically, serum, hepatic, and renal MDA levels increased by 75%, 90%, and 102%, respectively. TRF-treated rats had significantly (p<0.05) reduced activities of renal catalase, glutathione-S-transferase, and superoxide dismutase. Supplementation of Vit E ameliorated TFR-induced effects by decreasing the levels of MDA and enhancing the activities of renal antioxidative enzymes. The biochemical data were supported by histopathological findings from the slides. CONCLUSIONS: TFR increased oxidative stress and altered kidney function markers in the rats, whereas supplementation of Vit E attenuated these effects.

Protective effect of kolaviron, a biflavonoid from Garcinia kola seeds, in brain of Wistar albino rats exposed to gamma-radiation.

This study was designed to evaluate the protective effect of kolaviron (KV), a biflavonoid from Garcinia kola seeds, against gamma-radiation (5 Gy)-induced oxidative stress in brain of Wistar rats. Vitamin C (VC) served as standard antioxidant. Forty-four rats were divided into 4 groups of 11 animals each. One group was un-irradiated (normal), two groups were treated with KV and VC (250 mg/kg) for 6 weeks prior to and 8 weeks after irradiation, and fourth group was only irradiated. Rats were sacrificed 1 and 8 weeks after irradiation. Cellular alterations were monitored using changes in the levels of malondialdehyde (MDA)-an index of lipid peroxidation, superoxide dismutase (SOD), glutathione-S-transferase (GST), reduced glutathione (GSH), catalase (CAT), alanine and aspartate aminotransferases (ALT and AST), urea and creatinine. MDA levels increased significantly (p<0.05) by 90% and 151% after 1 and 8 weeks of irradiation. Furthermore, levels of GSH and antioxidant enzymes were significantly (p<0.05) decreased in gamma-irradiated animals. GSH and GST decreased by 61% and 43% after 1 week, and by 75% and 74%, after 8 weeks of exposure, respectively. gamma-Irradiation decreased SOD and CAT levels by 53% and 68%, respectively, and caused significant (p<0.05) increases in serum ALT, AST and urea after 8 weeks of exposure. Treatment with KV and VC significantly decreased the levels of MDA, ALT, AST and urea. The antioxidant indices were significantly ameliorated in KV-treated animals. These data suggest that kolaviron may protect against gamma-radiation-induced oxidative stress in brain of exposed rats.

Extract of Xylopia aethiopica (Annonaceae) protects against gamma-radiation induced testicular damage in Wistar rats.

Ionizing radiation is an important environmental risk factor and, a major therapeutic agent for cancer treatment. This study was designed to evaluate the protective effect of extract of Xylopia aethiopica (XA) on gamma-radiation-induced testicular damage in rats. Vitamin C (VC) served as the reference antioxidant during the study. The study consists of 4 groups of 11 rats each. Group I received corn oil (vehicle), groups II and IV were pretreated with XA (250 mg/kg) and VC (250mg/kg) for 6 weeks before and 8 weeks after exposure to gamma-radiation; group III was exposed to a single dose of gamma-radiation (5 Gy). Biochemical analysis revealed that gamma-irradiation caused a significant increase (p < .05) in serum and testicular lipid peroxidation (LPO) levels by 217% and 221%, respectively. Irradiated rats had markedly decreased testicular catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST), and reduced glutathione (GSH) levels. Irradiation resulted in 59% and 40% decreases in spermatozoa motility and live/dead sperm count, respectively, and a 161% increase in total sperm abnormalities. Histologically, testes of the irradiated rats showed extensive degenerative changes in the seminiferous tubules and defoliation of spermatocytes. Supplementation of XA and VC reversed the adverse effects of gamma-radiation on biochemical and histological indices of the rats. These findings demonstrated that Xylopia aethiopica has a protective effect by inhibiting oxidative damage in testes of irradiated rats.

Lead exposure increases oxidative stress in the gastric mucosa of HCl/ethanol-exposed rats.

AIM: To investigate the role of reactive oxygen species in the ulcer-aggravating effect of lead in albino rats. METHODS: Albino Wistar rats were randomly divided into three groups and treated orally with 100 mg/L (low dose) or 5000 mg/L (high dose) of lead acetate for 15 wk. A third group received saline and served as control. At the end of wk 15, colorimetric assays were applied to determine the concentrations of total protein and nitrite, the activities of the oxidative enzymes catalase and superoxide dismutase, and lipid peroxidation in homogenized gastric mucosal samples. RESULTS: Exposure of rats to lead significantly increased the gastric mucosal damage caused by acidified ethanol. Although the basal gastric acid secretory rate was not significantly altered, the maximal response of the stomach to histamine was significantly higher in the lead-exposed animals than in the unexposed control group. Exposure to low and high levels of lead significantly increased gastric lipid peroxidation to 183.2%+/-12.7% and 226.1%+/-6.8% of control values respectively (P<0.0). On the other hand, lead exposure significantly decreased catalase and superoxide dismutase (SOD) activities and the amount of nitrite in gastric mucosal samples. CONCLUSION: Lead increases the formation of gastric ulcers by interfering with the oxidative metabolism in the stomach.