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Ameliorative Effect of Vitamin C on Alterations in Thyroid Hormones Concentrations Induced by Subchronic Coadministration of Chlorpyrifos and Lead in Wistar Rats  [PDF]
Suleiman F. Ambali,Chinedu Orieji,Woziri O. Abubakar,Muftau Shittu,Mohammed U. Kawu
Journal of Thyroid Research , 2011, DOI: 10.4061/2011/214924
Abstract: The present study evaluated the ameliorative effect of vitamin C on alteration in thyroid hormones induced by low-dose subchronic coadministration of chlorpyrifos (CPF) and lead (Pb). Forty Wistar rats were divided into 4 groups of 10 animals each. Groups I and II were administered soya oil (2?mL/kg) and vitamin C (100?mg/kg), respectively. Group III was coadministered CPF (4.25?mg/kg ~1/20th LD50) and Pb (250?mg/kg ~1/20th LD50), respectively. Group IV was pretreated with vitamin C (100?mg/kg) and then coadministered with CPF (4.25?mg/kg) and Pb (250?mg/kg), 30?min later. The regimens were administered by gavage for a period of 9 weeks. The marginal decrease in serum triiodothyronine and thyroxine and the significant increase in the concentrations of thyroid stimulating hormone and malonaldehyde in the group coadministered with CPF and Pb were ameliorated by vitamin C partly due to its antioxidant properties. 1. Introduction Man and animals are exposed to a “soup” of chemical contaminants in the environment, which directly or indirectly affect their health and well-being. Pesticides and heavy metals are the most common environmental contaminants because of their respective widespread use in agriculture and industries. Hitherto, most studies on these chemical contaminants have centered on the examination of one single agent and therefore, current understanding of the toxicity of many environmental toxicants/pollutants is based primarily on toxicity studies performed on laboratory animals exposed to a single toxic agent [1, 2]. However, the environment is heavily contaminated with many chemicals, which interact with each other in such a way that modify their toxic response in humans and animals. Organophosphate (OP) compounds are the most widely used insecticides accounting for 50% of global insecticidal use [3] while Pb is the most widespread heavy metal contaminants with wide applications [4]. Occupational and environmental Pb exposure continues to be among the most significant public health problems [4–7]. Due to their persistent nature in the environment and their toxicodynamics, CPF and Pb have resulted in deleterious effects in man and animals [8]. The toxicity of Pb remains a matter of public health concern [9] due to its pervasiveness in the environment and the awareness about its toxic effects [10] at exposure levels lower than what was previously considered harmful [11]. Reproductive consequences of Pb exposure are widespread [12], affecting almost all aspects of reproduction [13]. Pb induces decreased sperm count and motility and increased
Hyperglycemia induced by subchronic co-administration of chlorpyrifos and lead in Wistar rats: Role of pancreatic lipoperoxidation and alleviating effect of vitamin C  [PDF]
SF Ambali
Biology and Medicine , 2011,
Abstract: Studies were conducted to evaluate the role of pancreatic lipoperoxidation on hyperglycemia induced by subchronicco-administration of chlorpyrifos (CPF) and lead (Pb) in Wistar rats and the ameliorative effect of vitamin C. Fortymale Wistar rats divided into 4 groups of 5 animals in each group were used for this study. Rats in group were dosedwith corn oil (2 ml/kg) while those in group II were dosed with vitamin C (100 mg/kg). Group III were co-administeredCPF ( 4.25 mg/kg~ 1/20th LD50) and Pb (250 mg/kg~1/20th LD50) while those in group IV were pretreated with vitaminC (100 mg/kg) and then co-administered with CPF (4.25 mg/kg) and Pb (250 mg/kg) 30 min later. The regimen wereadministered once daily by gavage for a period of 9 weeks. The rats were sacrificed and serum obtained from theblood samples were analyzed for glucose concentration. The liver and pancreas samples were analyzed for glycogenand malonaldehyde (MDA) concentrations, respectively. The study showed that co-administration of CPF and leadcaused increased glucose and MDA concentrations, and a reduced glycogen concentration. Pretreatment withvitamin C restored the concentrations of glucose, glycogen and MDA to apparently normal level. In conclusion,pretreatment with vitamin C restored the hyperglycemia and reduced glycogen concentration induced by coadministrationof CPF and Pb partly due to its antioxidant properties.
Effect of lead acetate on neurobehavioral development of rats
Mello, C.F.;Kraemer, C.K.;Filippin, A.;Morsch, V.M.;Rodrigues, A.L.S.;Martins, A.F.;Rubin, M.A.;
Brazilian Journal of Medical and Biological Research , 1998, DOI: 10.1590/S0100-879X1998000700010
Abstract: we investigated the effects of lead exposure during the pre- and postnatal period on the neurobehavioral development of female wistar rats (70-75 days of age, 120-150 g) using a protocol of lead intoxication that does not affect weight gain. wistar rats were submitted to lead acetate intoxication by giving their dams 1.0 mm lead acetate. control dams received deionized water. growth and neuromotor development were assessed by monitoring daily the following parameters in 20 litters: body weight, ear unfolding, incisor eruption, eye opening, righting, palmar grasp, negative geotaxis, cliff avoidance and startle reflex. spontaneous alternation was assessed on postnatal day 17 using a t maze. the animals' ability to equilibrate on a beaker rim was measured on postnatal day 19. lead intoxication was confirmed by measuring renal, hepatic and cerebral lead concentration in dams and litters. lead treatment hastened the day of appearance of the following parameters: eye opening (control: 13.5 ± 0.6, n = 88; lead: 12.9 ± 0.6, n = 72; p<0.05), startle reflex (control: 13.0 ± 0.8, n = 88; lead: 12.0 ± 0.7, n = 72; p<0.05) and negative geotaxis. on the other hand, spontaneous alternation performance was hindered in lead-exposed animals (control: 37.6 ± 19.7; lead: 57.5 ± 28.3% of alternating animals; p<0.05). these results suggest that lead exposure without concomitant undernutrition alters rat development, affecting specific subsets of motor skills.
Effect of lead acetate on neurobehavioral development of rats  [cached]
Mello C.F.,Kraemer C.K.,Filippin A.,Morsch V.M.
Brazilian Journal of Medical and Biological Research , 1998,
Abstract: We investigated the effects of lead exposure during the pre- and postnatal period on the neurobehavioral development of female Wistar rats (70-75 days of age, 120-150 g) using a protocol of lead intoxication that does not affect weight gain. Wistar rats were submitted to lead acetate intoxication by giving their dams 1.0 mM lead acetate. Control dams received deionized water. Growth and neuromotor development were assessed by monitoring daily the following parameters in 20 litters: body weight, ear unfolding, incisor eruption, eye opening, righting, palmar grasp, negative geotaxis, cliff avoidance and startle reflex. Spontaneous alternation was assessed on postnatal day 17 using a T maze. The animals' ability to equilibrate on a beaker rim was measured on postnatal day 19. Lead intoxication was confirmed by measuring renal, hepatic and cerebral lead concentration in dams and litters. Lead treatment hastened the day of appearance of the following parameters: eye opening (control: 13.5 ± 0.6, N = 88; lead: 12.9 ± 0.6, N = 72; P<0.05), startle reflex (control: 13.0 ± 0.8, N = 88; lead: 12.0 ± 0.7, N = 72; P<0.05) and negative geotaxis. On the other hand, spontaneous alternation performance was hindered in lead-exposed animals (control: 37.6 ± 19.7; lead: 57.5 ± 28.3% of alternating animals; P<0.05). These results suggest that lead exposure without concomitant undernutrition alters rat development, affecting specific subsets of motor skills.
Biochemical alterations induced by the acute exposure to combination of chlorpyrifos and lead in Wistar rats  [PDF]
H Krishna,AV Ramachandran
Biology and Medicine , 2009,
Abstract: Chlorpyrifos, a well known organophosphorus insecticide and heavy metal lead, was challenged to Wistar rats tostudy their interactive effects on biochemical parameters (clinical pathology) after acute exposure via oral gavaging.Hematology and clinical chemistry parameters were estimated after 14 days of exposure. In addition, serum butryland RBC cholinesterase was estimated on days 3rd and 15th of experimentation. The study was conducted using twodifferent dose levels of chlorpyrifos and lead acetate and grouped into seven groups. The parameters of hematologyand serum chemistry were analysed through automatic analyzers. No treatment related or interactive effects werenoticed in hematology values except for the reduced RBC, Hb content and HCT values in lead treated animals at1000mg/kg. A significant decrease in both serum and RBC cholinesterase enzymes were noticed in animals treatedwith chlorpyrifos at 50 mg/kg and in combination group (chlorpyrifos 50 + lead 1000 mg/kg), and increased inhibitionalong with delayed recovery was observed in the animals of combination group (i.e., chlorpyrifos plus lead).Chlorpyrifos in presence of lead increases the inhibition of both serum and RBC cholinesterase enzymes. The longlasting or persistence effects of CPF along with and lead may result in impaired cognitive functions of brainconsidering the role of cholinesterases in neuronal architecture of brain and other normal functioning of nervoussystem. Therefore, simultaneous exposure to a combination of chlorpyrifos and lead is considered to be moredangerous than to an exposure of either alone. In addition, serum chemistry revealed changes in concentrations ofglucose and sodium owing to lead treatment.
Subchronic toxicity (90 days) of StemEnhance in Wistar rats
Levent Dirikolu, Thushara Chakkath, Susan Ball-Kell, et al
Nutrition and Dietary Supplements , 2011, DOI: http://dx.doi.org/10.2147/NDS.S16503
Abstract: bchronic toxicity (90 days) of StemEnhance in Wistar rats Original Research (3320) Total Article Views Authors: Levent Dirikolu, Thushara Chakkath, Susan Ball-Kell, et al Published Date February 2011 Volume 2011:3 Pages 19 - 30 DOI: http://dx.doi.org/10.2147/NDS.S16503 Levent Dirikolu1, Thushara Chakkath1, Susan Ball-Kell2, Christy Elamma2, David J Schaeffer1 1Department of Comparative Biosciences, 2Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA Abstract: This study evaluated the subchronic toxicity of StemEnhance , an extract of the blue-green alga Aphanizomenon flos-aquae that is used as a health supplement. Groups of 12 rats of each sex were given either 5% glycerin in water (control) or 200 mg/kg of StemEnhance prepared in 5% glycerin in water for 90 days by oral gavage. The administration of StemEnhance had no effect on behavior, food and water intake, growth, or survival. Values at the end of dosing and observation periods did not reveal differences between treated and control groups for hematology and clinical chemistry. There were no significant differences in the gross and histopathology of the reproductive organs in either males or females. Sperm motility parameters were similar for control and treated males. Our results show that StemEnhance at doses ~7 times the maximum label-recommended daily dose did not produce adverse effects in Wistar rats after subchronic treatment.
Subchronic toxicity (90 days) of StemEnhance™ in Wistar rats  [cached]
Levent Dirikolu,Thushara Chakkath,Susan Ball-Kell,et al
Nutrition and Dietary Supplements , 2011,
Abstract: Levent Dirikolu1, Thushara Chakkath1, Susan Ball-Kell2, Christy Elamma2, David J Schaeffer11Department of Comparative Biosciences, 2Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USAAbstract: This study evaluated the subchronic toxicity of StemEnhance , an extract of the blue-green alga Aphanizomenon flos-aquae that is used as a health supplement. Groups of 12 rats of each sex were given either 5% glycerin in water (control) or 200 mg/kg of StemEnhance prepared in 5% glycerin in water for 90 days by oral gavage. The administration of StemEnhance had no effect on behavior, food and water intake, growth, or survival. Values at the end of dosing and observation periods did not reveal differences between treated and control groups for hematology and clinical chemistry. There were no significant differences in the gross and histopathology of the reproductive organs in either males or females. Sperm motility parameters were similar for control and treated males. Our results show that StemEnhance at doses ~7 times the maximum label-recommended daily dose did not produce adverse effects in Wistar rats after subchronic treatment.Keywords: algal toxicology, blue-green algae, cyanobacteria, Aphanizomenon flos-aquae
Subchronic chlorpyrifos-induced clinical, hematological and biochemical changes in swiss albino mice: protective effect of vitamin e
Suleiman F. Ambali,Akanbi D O, Oladipo O O, Yaqub LS, Kawu MU
International Journal of Biological and Medical Research , 2011,
Abstract: Forty adult Swiss albino mice of either sex divided into 4 groups of 10 mice in each group were used to evaluate the ameliorating effect vitamin E on hematological and serum biochemical changes induced by subchronic chlorpyrifos (CPF) exposure. Group I (control~C/oil) and group II (VE) were administered corn oil (2 ml/kg) and vitamin E (75 mg/kg), respectively. Group III was administered CPF (21.3 mg/kg~ 1/5th LD50) only while group IV (VE + CPF) was pretreated with vitamin E (100 mg/kg) followed by CPF administration, 30 min later. The regimens were administered orally by gavage, every other week days for a period of ten weeks. The mice were evaluated for signs of toxicity and weekly body weight changes. At the end of the dosing period, blood samples collected were analyzed for packed cell volume, total red blood cell, white blood cell and total protein. The sera obtained from the blood samples were analyzed for the levels of Na+, K+, Cl-, total protein, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and malonaldehyde. The results showed that pretreatment with vitamin E ameliorated deficits in clinical, body weight, hematological and biochemical changes induced by repeated CPF administration in mice, partly due to its antioxidant properties.
Evaluation of the acute and subchronic oral toxicity of ethanol extract from Valeriana pavonii species in Wistar rats
Olaya,María del Pilar; Lozano,María Constanza; Botero,Lucía; Rincón,Javier; Guerrero,Mario Francisco;
Colombia Médica , 2010,
Abstract: introduction: one of the most frequent problems found in medicinal plants is the absence of clinical, toxicological, and pharmacological studies. valeriana pavonii is one of the species used in colombia as an anxiolytic. further study of this specie is rendered to add information in the toxicological area. objective: the acute and subchronic oral toxicity of v. pavonii ethanolic extract was evaluated in wistar rats of both sexes. materials and methods: the rats were distributed into four groups: the control group received the vehicle (0. 5 ml/100 g of corporal weight) and the other three groups received increasing levels of the dosage for 90 days to evaluate characteristics like physical exam, laboratory test (blood chemistry and haematology), and anatomopathological findings. results: this study reveals that there were no signs of toxicity, mortality, or significant alterations attributable to the ethanolic extract of v. pavonii. conclusions: the not observed adverse effect levels (noael) of v. pavonii ethanolic extract were 2000 and 1000 mg/kg of body weight for the acute and subchronic toxicity studies, respectively.
Evaluation of the acute and subchronic oral toxicity of ethanol extract from Valeriana pavonii species in Wistar rats
María del Pilar Olaya,María Constanza Lozano,Lucía Botero,Javier Rincón
Colombia Médica , 2010,
Abstract: Introduction: One of the most frequent problems found in medicinal plants is the absence of clinical, toxicological, and pharmacological studies. Valeriana pavonii is one of the species used in Colombia as an anxiolytic. Further study of this specie is rendered to add information in the toxicological area.Objective: The acute and subchronic oral toxicity of V. pavonii ethanolic extract was evaluated in Wistar rats of both sexes.Materials and methods: The rats were distributed into four groups: the control group received the vehicle (0.5 mL/100 g of corporal weight) and the other three groups received increasing levels of the dosage for 90 days to evaluate characteristics like physical exam, laboratory test (blood chemistry and haematology), and anatomopathological findings.Results: This study reveals that there were no signs of toxicity, mortality, or significant alterations attributable to the ethanolic extract of V. pavonii.Conclusions: The Not Observed Adverse Effect Levels (NOAEL) of V. pavonii ethanolic extract were 2000 and 1000 mg/kg of body weight for the acute and subchronic toxicity studies, respectively.
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