Neuroprotective Effect of Sweet Potato Petiole and Leaf Dry-Powder in a Gerbil Model of Transient Cerebral Ischaemia

This study aimed to investigate the neuroprotective effects of sweet potato petioles and leaves (PL), which are rich in polyphenols with antioxidant and anti-inflammatory properties, using a gerbil model of transient cerebral ischaemia. We also evaluated the preventive potential of continuous PL intake against ischaemic brain injury.

Custom diets, formulated by adding 1% or 10% PL powder to MF standard diet, were provided ad libitum to gerbils after a 5-min bilateral common carotid artery occlusion for 7 days (post-ischaemia PL providing group). Diets were also provided from 7 days before to 7 days after the ischaemic episode (pre-ischaemia PL providing group, total 14 days). The number of viable neurons in the hippocampal CA1 region was assessed on postoperative Day 7.

The number of viable neurons was significantly higher in both post- and pre-10% PL groups compared with that in the MF group (43.90 ± 3.28 in MF, 66.55 ± 6.60 in post 10% PL and 69.56 ± 3.30 in pre 10% PL; p < 0.01), although no significant differences were observed in the post- and pre-1% PL groups (55.49 ± 3.19 in post 1% PL 47.27 ± 2.61 in pre 1% PL). Moreover, comparison between the pre- and post-10% PL groups indicated that pre-ischaemic administration resulted in slightly higher number of viable neurons.

Continuous intake of sweet potato PL may support the prevention and mitigation of neuronal damage in ischaemic events.