Tualang honey prevents neuronal damage in medial prefrontal cortex (mPFC) through enhancement of cholinergic system in male rats following exposure to normobaric hypoxia

Background: Medial prefrontal cortex (mPFC) is considered to be involved in human cognition to mPFC in terms of learning and memory. Hypoxia is one of the crucial factors causing secondary damage in cerebral hemorrhage and traumatic brain injury. However, the underlying mechanisms and possible therapeutic approach to prevent neuronal damage has not been attempted yet. Therefore, the present study aimed to investigate the role of Tualang honey on medial prefrontal cortical neuronal morphology and cholinergic markers such as acetylcholine (ACh) and acetylcholinesterase (AChE) following exposure to normobaric hypoxia in rats. Material and methods: Adult male Sprague-Dawley rats were divided into four groups: (i) sucrose treated non-hypoxia, (ii) sucrose treated hypoxia, (iii) Tualang honey treated non-hypoxia and (iv)Tualang honey treated hypoxia. Rats received sucrose (1 mL of 7.9%) and Tualang honey (0.2 g/kg), respectively, for 2 weeks prior to hypoxia exposure. Morphological study was performed by using Nissl staining and cholinergic markers were estimated by ELISA technique. Results and discussion: Sucrose treated hypoxia group showed significantly lower mean ACh and higher mean AChE concentrations (P<0.05) compared to sucrose and honey treated non-hypoxia groups. Interestingly, mean ACh concentration was significantly increased and mean AChE concentration was significantly decreased in Tualang honey treated hypoxic rats compared to sucrose treated hypoxic rats. Morphological data showed that hypoxia caused neuronal damage in mPFC in sucrose treated hypoxia group whereas Tualang honey treated hypoxia group significantly prevent neuronal damage. Conclusion: Tualang honey protects hypoxia-induced mPFC neuronal damage through improvement of the brain cholinergic markers in male rats exposed to normobaric hypoxia.