– Influence of Zinc Supplementation on the Pathology of subchronic Exposure of Wistar Rats to Glyphosate –
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ABSTRACT
Glyphosate used in this study is the active ingredient of the glyphosate – based herbicide, Bushfire®. The study was conducted to determine the influence of zinc supplementation on the pathology of subchronic exposure of Wistar rats to glyphosate.
Sixty adult male and female Wistar rats were used. Twelve rats were used to determine the LD50 which was 3750 mg kg-1 and forty eight were randomized in to six groups of eight rats each, four males and four females.
Group I (DW) served as control and were administered only distilled water (2 ml kg-1), group II (Z) were administered zinc only (50 mg kg-1), group III (G) were administered glyphosate only (375 mg kg-1, 10 % of the .
LD50), group IV (Z + G) were pretreated with zinc (50 mg kg-1) and glyphosate was administered (375 mg kg-1). Those in group V (GC) were administered glyphosate (14.4 mg kg-1, 1: 50 glyphosate : distilled water respectively, as being used for field application) and those in group VI (Z + GC) were pretreated with zinc (50 mg kg-1) and glyphosate was administered (14.4 mg kg-1 , 1 : 50 glyphosate : distilled water respectively).
The treatment regimens were administered orally by gavage once daily for eight weeks.
At the end of the study period, blood samples were collected and analysed for haematological and serum – biochemical parameters which included packed cell volume, hemoglobin, total leucocyte count, absolute and differential leucocyte count, total protein, albumin, globulin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, Na+, K+, Cl-, HCO- 3, Ca2+, PO- 4, urea and creatinine.
Alterations in the values of haematological and serum – biochemical parameters induced by glyphosate exposure were differentially ameliorated by pretreatment with zinc.
Histopathologic examination revealed neuronal degeneration, degenerated hepatic cells especially at the portal areas and congested central vein, depopulated splenic cells in both red and white pulps.
Degenerated glandular pancreatic acinar cells, glomerular degeneration, few mononuclear cells infiltration into the interstices with renal tubular necrosis and degenerated mucosal epithelial cells of the stomach that involved the muscularis mucosa and the glands.
No observable lesions in the testis and the uterus. Supplementation with zinc ameliorated the microscopic lesions induced by glyphosate exposure in these organs.
In conclusion, this study showed the ameliorative effect of zinc on subchronic glyphosate – induced pathological changes in Wistar rats.
TABLE OF CONTENTS
Title page – – – – – – – – – – i
Declaration – – – – – – – – – – ii
Certification – – – – – – – – – – iii
Dedication – – – – – – – – – – iv
Acknowledgement – – – – – – – – – v
Abstract – – – – – – – – – – vii
Table of Contents – – – – – – – – – ix
List of Tables – – – – – – – – – – xii
List of Figures – – – – – – – – – – xiii
List of Plates – – – – – – – – – – xv
List of Abbreviations – – – – – – – – xvii
CHAPTER 1 INTRODUCTION – – – – – – – 1
1.1 Statement of Research Problem – – – – – – – 3
1.2 Justification – – – – – – – – – 4
1.3 Research Hypothesis – – – – – – – – 4
1.4 Aim – – – – – – – – – – 5
1.5 Objectives – – – – – – – – – – 5
CHAPTER 2 LITERATURE REVIEW – – – – – – 6
2.1 Classification of Pesticides – – – – – – – 6
2.2 Routes of Exposure to Organophosphates- – – – – – 14
2.3 Mode of action of Organophophates – – – – – – 16
2.4 Kinetics – – – – – – – – – – 17
2.5 Free Radicals – – – – – – – – – 20
2.5.1 Reactions involving Free Radicals – – – – – – 21
2.5.2 Free Radical Formation – – – – – – – – 21
2.6 Oxidative Stress: What is it? – – – – – – – 23
2.7. What is an Antioxidant? – – – – – – – – 24
2.7.1 Types of Antioxidants – – – – – – – – 24
2.8 Effect of Organophosphates on Haematology in Animals and the Role of Antioxidants 27
2.9 Effect of Organophosphates on Serum – Biochemical Parameters in Animals and the Role of Antioxidants – – 33
2.10 Histopathological Effect of Organophosphates in Animals and the Role of Antioxidants – – – – – – – – 39
2.11 Effect of Zinc Supplementation on Oxidative Stress in Animals – – 47
CHAPTER 3 MATERIALS AND METHODS – – – – – 49
3.1 Experimental Animals – – – – – – – – 49
3.2 Chemical Source – – – – – – – – – 49
3.3 Experimental Design – – – – – – – – 50
3.3.1 Determination of Median Lethal Dose (LD50) – – – – 50
3.3.2 Subchronic Toxicity Study – – – – – – – 50
3.3.3 Haematological Analysis – – – – – – – 51
3.3.4 Serum-Biochemical Analysis – – – – – – – 51
3.3.5 Histopathological examination – – – – – – – 52
3.3.6 Statistical Analysis – – – – – – – – 52
CHAPTER 4 RESULTS – – – – – – – – 53
4.1 Clinical Signs – – – – – – – – – 53
4.2. Haematology – – – – – – – – – 53
4.2.1 Effect of Treatments on Packed Cell Volume (PCV) – – – – 53
4.2.2 Effect of Treatments on Haemoglobin (Hb) Concentration – – – 54
4.2.3 Effect of Treatments on Total White Blood Cell (WBC) Counts – – 54
4.2.4 Effect of Treatments on Differential Leucocyte Counts (DLC) – – 54
4.3 Blood Chemistry – – – – – – – – – 55
4.3.1 Effect of Treatments on Serum Protein, Albumin and Globulin Concentrations 55
4.3.2 Effect of Treatments on Serum Enzymes- – – – – 56
4.3.3 Effect of Treatments on Serum Electrolyte Concentrations – – – 56
4.3.4 Effect of Treatments on Serum Urea Concentration – – – – 58
4.3.5 Effect of Treatments on Serum Creatinine Concentration – – – 58
4.4 Histopathological Findings – – – – – – – 71
CHAPTER 5 DISCUSSION – – – – – – – 92
CHAPTER 6 SUMMARY, CONCLUSION AND RECOMMENDATIONS – 107
6.1 Summary – – – – – – – – – – 107
6.2 Conclusion – – – – – – – – – – 108
6.3 Recommendations – – – – – – – – – 108
REFERENCES – – – – – – – – – 110
APPENDIX – – – – – – – – – – 124
INTRODUCTION
Pesticide is any substance or mixture of substances intended for preventing, repelling or mitigating any pest. Pest include insects, plant pathogens, weeds, molluscs, birds, mammals, fish, nematodes and microbes that destroy property, spread disease or are a vector for disease or cause of nuisance (EPA, 2007; FAO, 2002).
Organophosphates are the most widely used pesticides owing to their high efficacy, less persistence and more biodegradable nature than the organochlorines (Jirachayabhas et al., 2004). Although there are benefits to the use of pesticides, there are also setbacks such as potential toxicity to humans and other animals (FAO, 2002).
Glyphosate (phosphonomethyl glycine) was first reported as a herbicide in 1971, and is said to be the world’s biggest selling herbicide (Monsanto, 1992). It is a broad-spectrum herbicide widely used to kill unwanted plants both on agricultural and non-agricultural landscapes (Temple et al., 1992).
As a herbicide, glyphosate works by being absorbed into the plant mainly through its leaves, but also through soft stalk tissues.
It is then transported throughout the plant where it acts on various enzyme systems, inhibiting amino acid m metabolism in what is known as shikimic acid pathway. This pathway exists in higher plants and microorganisms but not in animals.
REFERENCES
Abdallah S.M and Samman S. (1993). The Effect of Increasing Dietary Zinc on the Activity of Superoxide dismutase and Zinc Concentration in Erythrocytes of Healthy Female Subjects. European Journal of Clinical Nutrition. 47: 327 – 332.
Abdel – Rahman, A., Dechkovskaia, A.M., Goldstein, L.B., Bullman, S.H., Khan, W., El Masry, E.M. and Abou – Donia, M.B. (2004). Neurological Deficits Induced by Malathion, DEET and Permethrin, Alone or in Combinnation in Adult Rats. Journal of Toxicology and Environmental Health, 67: 331 – 356.
Abou Donia, M. B. and Graham, D. G. (1978). Delayed Neurotoxicity from Long – term Low level Administration of Leptophos to the Comb of Hens. Toxicology and Pharmacology, 46: 199 – 213.
Adachi, M. and Ishii, H. (2002). Role of Mitochondria in Alcoholic Liver Injury. Free Radical Biology and Medicine, 32: 487 – 491.
Adam, A., Marzuki, A. and Abdul, A. (1997). The oral and intratrachael toxicities of Roundup® and its components to rats. Veterinary and Human Toxicology, 39: 147 – 151.
Adedeji, O. B., Adedeji, O. A., Adeyemo, O. K. and Agbede S. A. (2009). Acute Effects of Diazinon on Blood Parameters in the African Catfish (Clarias gariepinus). The Internet Journal of Hematology, 5(2): 32 – 49.
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