The potential neuroprotective effect of allicin and melatonin in acrylamide-induced brain damage in rats

Acrylamide (ACR) is an unsaturated monomer that entered in various fields however, it is a potent neurotoxic. The present study target is to explore the neuroprotective efficacy of allicin and melatonin on ACR-induced neurotoxicity. Thirty-six male adult rats were non-selectively separated into six groups: placebo, allicin (20 mg/kg b.w daily per os), melatonin (10 mg/kg b.w 3 times/week per os), ACR (50 mg/kg b.w daily per os), ACR + allicin and ACR + melatonin with the same doses. The assessment of brain biomarkers, neurotransmitters, antioxidative status, Nrf2 signalling pathway, and histopathological analyses were performed following 21 days. ACR exposure enhanced the brain lipid and DNA oxidative damage as well as a reduction in the GSH levels. The obvious brain oxidative injuries was contributed to distinct brain dysfunction that was assured by alteration of brain neurotransmitters (serotonin, dopamine, acetylcholine, and acetylcholinesterase), and pathological brain lesions. Furthermore, ACR exposure increased hydroxy deoxy guanosine (8-OHdG), tumor necrosis factor (TNF) and amyloid protein (AB-42). Finally, the mRNA transcripts of brain Keap-1, Nrf2, and NF-kB were up regulated after ACR intoxication. Interestingly, allicin and melatonin alleviated the ACR-induced brain damage assessed by normalization of the mentioned analyses. The present study demonstrated the protective role of both allicin and melatonin on ACR-prompted neuropathy by alleviation of redox imbalance and enhancement of neurotransmitters as well as relieving DNA damage and anti-inflammatory effect.