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British Journal of Healthcare and Medical Research - Vol. 12, No. 02
Publication Date: April 25, 2025
DOI:10.14738/bjhmr.1202.18422.
Akande, M. G., Oladele, G. M., Mikail, H. G., Adeniran, L. A., & Chibuogwu, I. C. (2025). Impacts of L-Arginine on Haematological and
Serum Biochemical Indices of Rats Exposed to Chlorpyrifos. British Journal of Healthcare and Medical Research, Vol - 12(02). 82-89.
Services for Science and Education – United Kingdom
Impacts of L-Arginine on Haematological and Serum Biochemical
Indices of Rats Exposed to Chlorpyrifos
Motunrayo Ganiyat Akande
Department of Pharmacology and Toxicology,
Faculty of Veterinary Medicine, University of Abuja, Nigeria, 920001
Gbenga Michael Oladele
Department of Pharmacology and Toxicology,
Faculty of Veterinary Medicine, University of Abuja, Nigeria, 920001
Hudu Garba Mikail
Department of Pharmacology and Toxicology,
Faculty of Veterinary Medicine, University of Abuja, Nigeria, 920001
Lateef Ariyo Adeniran
Department of Veterinary Physiology and Biochemistry,
Faculty of Veterinary Medicine, University of Abuja, Nigeria, 920001
Ijeoma Chika Chibuogwu
Department of Theriogenology, Faculty of Veterinary Medicine,
University of Abuja, Nigeria, 920001
ABSTRACT
Chlorpyrifos is an organophosphorus insecticide that is applied expansively for
pest control and its usage has been linked to several cases of poisoning. L-arginine
is an α-amino acid that is crucial in protein biosynthesis and it has been reported to
exert bioprotective effects in the body. The research was conducted in order to find
out the impacts of L-arginine (AG) on haematological and serum biochemical
indices in male Wistar rats exposed to chlorpyrifos. Thirty five rats were
distributed into five groups. They received the following treatments by oral gavage
for 28 days: distilled water [DT group], olive oil [LV; 1 ml/kg], chlorpyrifos (CF
group; 8.5 mg/kg), L-arginine (AG; 100 mg/kg), chlorpyrifos (8.5 mg/kg)+L- arginine (100 mg/kg). The rats were sacrificed after the termination of the
research. Subsequently, haematological and serum biochemical parameters were
assessed. A significant (p < 0.05) reduction in the MCV of the CF group compared to
the LV group was observed. Additionally, a substantial (p < 0.05) elevation was
recorded in the MCHC of the CF group relative to the AG group. There were
significant reductions in the calcium levels, while the magnesium levels were
remarkably elevated in the CF and CF+AG groups compared to the DT and LV groups
respectively. However, no significant alteration was noticed in the serum oxidative
stress parameters (malondialdehyde, catalase and superoxide dismutase) that
were analyzed. In this study, CF disrupted some haemato-biochemical parameters
while AG minimally suppressed its effects. Further studies are warranted to
expound the mechanisms of toxicity of CF, and the bioprotective propensity of AG.
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Akande, M. G., Oladele, G. M., Mikail, H. G., Adeniran, L. A., & Chibuogwu, I. C. (2025). Impacts of L-Arginine on Haematological and Serum
Biochemical Indices of Rats Exposed to Chlorpyrifos. British Journal of Healthcare and Medical Research, Vol - 12(02). 82-89.
URL: http://dx.doi.org/10.14738/bjhmr.1202.18422.
Keywords: L-arginine, chlorpyrifos, haematology, serum biochemistry, rats
INTRODUCTION
Chlorpyrifos (CF) is an organophosphorus insecticide and acetylcholinesterase inhibitor that
evokes severe cholinergic toxicity through the integumentary, respiratory or oral routes
(Dawson et al., 2010). It is applied for pest management in agricultural, veterinary and
residential settings (Singh et al., 2018). CF application is linked with disorders in the nervous,
cardiovascular, respiratory, immunological, and reproductive systems (Sepand et al., 2020;
Wang and Steinberg, 2022). Apart from cholinesterase inhibition, other identified mechanisms
of CF toxicity include inflammation, endocrine disruption, oxidative and nitrosative stress, as
well as apoptosis (Albasher et al., 2019; Küçükler et al., 2021; Nandi et al., 2022).
A disruption between the levels of antioxidants and pro-oxidants could evoke oxidative stress
in biological systems (Qiu et al., 2019). CF has been shown to elicit aberrations in the
haematological and biochemical indices of laboratory animals through the induction of
oxidative stress (Aung et al., 2020; Kunnaja et al., 2021).
L-arginine is a conditionally essential amino acid and an antioxidant that is capable of
alleviating oxidative stress (Zhang et al., 2019; Akinrinde et al., 2021). It is a crucial precursor
for proline, polyamines, glutamate and nitric oxide synthesis (Shaki et al., 2021).
The aim of the proposed research was to find out if L-arginine, the amino acid, bioprotective
agent and antioxidant, could counteract the subacute toxic effects of chlorpyrifos, a broadly
used insecticide by farmers in Nigeria, on haemato-biochemical indices in male Wistar rats.
MATERIALS AND METHODS
The research was conducted at the Experimental Animal House, Faculty of Veterinary Medicine,
University of Abuja Main Campus, Federal Capital Territory, Abuja, Nigeria. Thirty five (35)
male rats were used and procured from the National Veterinary Research Institute (NVRI) Vom,
Plateau State, Nigeria. They were accommodated in suitable cages at 23−25 oC, 12 hours/12
hours light/dark cycle at the Experimental Animal House, Faculty of Veterinary Medicine,
University of Abuja. The rats had free access to chow and water.
The investigation was approved by the University of Abuja Research Ethics Committee (UAV- 23-146). The animals were catered for in harmony with the guiding principles of the National
Institute of Health Guide for Care and Use of Laboratory animals (Garber et al., 2011).
Chemicals
A commercial grade of chlorpyrifos (Chloview®, 20 % emulsifiable concentrate) was procured
from an agrochemical company in Abuja, Nigeria, and it was reconstituted in olive oil before
administration to the rats. An analytical grade of L-arginine was purchased from Sigma
Aldrich®, Germany. L-arginine was reconstituted in distilled water to obtain a 100 mg/ml
solution before it was given to the rats on a daily basis.
The Subacute Toxicological Study
The rats were weighed and assigned randomly to five groups (n = 7). The experimental groups
and the treatments administered to them were as follows: Distilled water (DT) group, olive oil
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British Journal of Healthcare and Medical Research (BJHMR) Vol 12, Issue 02, April-2025
Services for Science and Education – United Kingdom
(LV) group at 1 ml/kg, chlorpyrifos [CF, 8.5 mg/kg, 0.1LD50, LD50 = 85 mg/kg, Akande et al.
(2014)]. L-arginine (AG) at 100 mg/kg, and chlorpyrifos (8.5 mg/kg) and L-arginine (100
mg/kg) (CF+AG).
The treatments were administered to the rats once daily by oral gavage for 28 days and they
were inspected for clinical signs of intoxication. After the study ended, blood samples were
collected through cardiac puncture following chloroform anaesthesia.
Laboratory Investigations
Evaluation of Haematological Parameters:
Three millilitres of the rats’ blood samples were dispensed in ethylene diamine tetraacetic acid
sample bottles for the evaluation of haematological parameters. The erythrocyte indices were
computed. The evaluation was conducted with the use of an automatic haematology analyzer
(Mythic 18® Orphée, Geneva, Switzerland).
Assessment of Serum Biochemical Parameters:
Moreover, the rats’ blood specimens (three millilitres) were placed in anticoagulant-free tubes.
The blood specimens clotted and were incubated for 30 minutes. Subsequently, they were
centrifuged at 1000 x g for 5 minutes to obtain clear straw coloured serum specimens for the
estimation of biochemical parameters.
Assessment of Serum Electrolytes Levels:
Blood samples were collected from the rats and analyzed for levels of serum electrolytes
(sodium, potassium, calcium, magnesium and chloride). The electrolytes were evaluated with a
Clinical Chemistry Analyzer (Erba Diagnostics, Mannheim, Germany).
Determination of Malondialdehyde Concentration in the Serum of the Experimental
Animals:
The malondialdehyde (MDA) levels were estimated in the serum samples by using an MDA
assay kit (Elabscience Biotechnology Incorporation, Texas, USA). The method described by
Draper and Hadley (1990) was applied. The absorbance was measured with an ultraviolet
spectrophotometer at 532 nm. The MDA level in the samples was computed with the
absorbance coefficient of MDA-TBA complex 1.56 x 105/cm/M.
Assays of Antioxidant Enzymes Activities:
Superoxide dismutase (SOD) activity was measured in the serum samples of the rats with an SOD
assay kit (Elabscience Biotechnology Incorporation, Texas, USA). The method was predicated
on the autoxidation of haematoxylin (Martin et al., 1987). Catalase (CAT) activity was estimated
in the serum samples with a CAT assay kit (Elabscience Biotechnology Incorporation, Texas,
USA). The procedure was based on the consumption of hydrogen peroxide substrate (Beers and
Sizer, 1952). Glutathione peroxidase (GPx) level was appraised with the NWLSSTM activity assay
kit. The assay was based on the oxidation of reduced glutathione to produce oxidized
glutathione (Paglia and Valentine, 1967).
Data Analysis
The data derived from the research were stated as mean + standard error of the mean. The data
were scrutinized with one-way analysis of variance combined with Tukey's post hoc test