Neuroprotective effects of a polyphenolic white grape juice extract in a mouse model of experimental autoimmune encephalomyelitis

In the last 20 years, wine phenolic compounds have received increasing interest since several epidemiological studies have suggested associations between regular consumption of moderate amount of wine and prevention of certain chronic pathologies, such as neurodegenerative diseases. This study was aimed to investigate the possible neuroprotective role of a polyphenolic white grape juice extract (WGJe) in an experimental mice model of autoimmune encephalomyelitis (EAE), the most commonly used model for multiple sclerosis (MS) in vivo. EAE mimics the main features of MS, including paralysis, weight loss, demyelination, central nervous system (CNS) inflammation and blood-brain barrier (BBB) breakdown. Our study demonstrated that oral administration of WGJe (20 and 40 mg/kg/day) may exert neuroprotective effects against MS, diminishing both clinical signs and histological score typical of disease (lymphocytic infiltration and demyelination). In particular, by western blot, histological evaluations and immunolocalization of the main markers of inflammation, oxidative stress and apoptosis (TNF-α, iNOS, Nitrotyrosine, PARP, Foxp3, Bcl-2, Caspase 3 and DNA fragmentation), we documented that WGJe counteracts the alteration of all these inflammatory and oxidative pathway, without any apparent sign of toxicity. On these bases, we propose this natural product as putative novel helpful tools for the prevention of autoimmune and neurodegenerative diseases such as MS. WGJe could have considerable implication for future therapies of MS, and this study may represents the starting point for further investigation on the role of WGJe in neuroinflammation.