Role of Elevated Dosage of Vitamin A on the Prefrontal Cortex of Adult Male Wistar Rats Exposed to Methamphetamine
Ezejindu Damian Nnabuihe
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Joshua Izuchukwu Abugu
*
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria and Department of Human Anatomy, Fculty of Basic Medical Sciences,State University of Medical and Applied Sciences, Igbo-Eno, Enugu State, Nigeria.
Enemuo Ijeoma
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Okeke Somadina Nnamdi
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
K. Ogbuokiri Doris
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Okeke Henry Kachikwuru
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Ekoh Augustine Alobu
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Benedict Nzube Obinwa
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Chinyere Elizabeth Eze
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Nwaefulu Kester Eluemunor
Department of Physiology, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Sobanke A. Omolara
Department of Physiology, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Chidinma Ifeyinwa Mmaju
Department of Physiology, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Okafor Anulika Jacinta
Department of Physiology, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Chuka-Onwuokwu Ngozi Cynthia
Department of Physiology, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Ejiogu Ikedichukwu Chibueze
Department of Biochemistry, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Nwoko Sebastine Okechukwu
Department of Biochemistry, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Wuraola Serah Nnaemeka
Department of Biochemistry, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria.
Ebi Victory Chinecherem
Department of Medicine, College of medicine, University of Calabar, Cross River State, Nigeria.
Agu Augustine Uchenna
Department of Anatomy, Faculty of Basic Medical Sciences, University of Nigeria, Enugu Campus, Enugu State, Nigeria.
Ugwu Augustus Uchenna
Department of Anatomy, Faculty of Basic Medical Sciences, University of Nigeria, Enugu Campus, Enugu State, Nigeria.
Nwodo Ndubuisi Francis
Department of Human Anatomy, Faculty of Basic Medical Sciences, Madonna University, Rivers State, Nigeria.
Elemuo Chukwuebuka Stanley
Department of Anatomy, Chukwuemeka Odumegwu Ojukwu University, Uli Campus, Anambra State, Nigeria.
Agbai Johnson Ukwa
Department of Human Anatomy, Faculty of Basic Medical Sciences, Abia State University, Uturu, Abia State, Nigeria.
Muorah Chinecherem Onyekachi
Department of Nursing science, Christopher University, Ogun State, Nigeria.
Ozoemena Chiadikobi Lawrence
Department of Human Anatomy, Fculty of Basic Medical Sciences,State University of Medical and Applied Sciences, Igbo-Eno, Enugu State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Methamphetamine (METH), a highly addictive psychostimulant, is known to induce neurotoxicity in brain regions involved in cognitive processing, particularly the prefrontal cortex (PFC). This damage is mediated by oxidative stress, inflammation, and neuronal degeneration. Vitamin A, particularly in its active form, retinoic acid, contributes to brain health by influencing gene expression, neuronal survival, and plasticity. This study investigated the potential protective role of an elevated dose of vitamin A in the prefrontal cortex of adult male Wistar rats exposed to methamphetamine. Twenty rats were randomly divided into four groups (n = 5): Group A (control), Group B (METH only; 5 mg/kg at 3-hour intervals within 12 hours each day), Group C (vitamin A only; 2.5 mg/kg), and Group D (METH, 5 mg/kg at 3-hour intervals within 12 hours each day, plus vitamin A, 2.5 mg/kg). The animals received feed and water, and the treatments were administered orally for 28 consecutive days. After the final administration, the animals were sedated and sacrificed; their brains were harvested, fixed in 10% neutral-buffered formalin, and processed for histological examination using haematoxylin and eosin (H&E) staining. Body-weight, oxidative-stress biomarker, and histological findings indicated that methamphetamine exposure caused weight loss, increased oxidative stress, and severe neuronal damage. However, co-administration of high-dose vitamin A was associated with increased body weight, reduced oxidative stress, and milder neuronal damage. These findings suggest a potential neuroprotective effect of vitamin A against METH-induced damage under the experimental conditions.
Keywords: Methamphetamine, vitamin A, prefrontal cortex, Wistar rats, oxidative stress, neurotoxicity, neuroprotection, malondialdehyde, glutathione, superoxide dismutase, histopathology