Role of Vitamin-A on the Cerebral 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.
Ogbuokiri Doris K.
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) can induce oxidative stress and structural injury in the cerebral cortex, whereas vitamin A participates in antioxidant defence and neural maintenance. This study evaluated the effect of low-dose vitamin A on methamphetamine-induced cortical changes in adult male Wistar rats. Twenty rats were allocated to four groups (n = 5): control, METH only, vitamin A only and combined METH plus vitamin A. METH was administered orally at 5 mg/kg at 3-hour intervals within 12 hours per day, while vitamin A was administered orally at 0.7 mg/kg once daily for 28 consecutive days. Body weight, elevated plus-maze performance, cerebral-cortex malondialdehyde, glutathione and superoxide dismutase levels, and cortical histoarchitecture were assessed. METH-only exposure was associated with reduced body weight, a higher malondialdehyde level, lower glutathione and superoxide dismutase activities, altered open-arm time and marked cortical degeneration. Co-administration of vitamin A was associated with improved body-weight change, oxidative-stress indices closer to control values and better preservation of cortical architecture than METH-only treatment. The vitamin A-only group showed weight gain, antioxidant-marker values near those of the control group and largely preserved cortical morphology. Under the experimental conditions, low-dose vitamin A was associated with partial attenuation of methamphetamine-induced oxidative and histological changes in the cerebral cortex. These findings are limited to the measured outcomes in a small animal model and require confirmation through larger studies with clearly defined dosing and additional molecular assessments.
Keywords: Methamphetamine, vitamin A, cerebral cortex, Wistar rats, oxidative stress, malondialdehyde, glutathione, superoxide dismutase, neurotoxicity, histopathology