Neuroprotective effect of vitamin D3 toward apoptosis induced by ethanol in CA1 pyramidal cells of rat hippocampus

Abstract

As an antioxidant, Vitamin D3 can protect neurons from damage caused by oxidative stress.
Ethanol is known to have neurotoxic effects by inducing an increase in oxidative stress. One of
the brain regions that is most sensitive to neurotoxic effects induced by ethanol is hippocampus,
especially its CA1 region. This study was aimed to determine the neuroprotective effects of
vitamin D3 in preventing the apoptosis in CA1 hippocampal pyramidal cells induced by ethanol.
Fifteen male Wistar rats (Rattus norvegicus) were randomly divided into three groups. The control
group was given daily normal saline solution intraperitoneally. The ethanol group was given
20% ethanol solution at a dose of 3 g/kg BW/day intraperitoneally. The vitamin D3 group was
given vitamin D3 1 μg/kg BW/day in 20% ethanol solution at a dose of 3 g/kg BW/day
intraperitoneally. After 30 days, the rats were sacrificed, their brains were perfused with PBS
followed by fixative and the hippocampus was dissected for histological preparations.
Immunohistochemical staining for caspase was performed. Percentage of apoptotic CA1
hippocampal pyramidal cells was calculated. The results showed there was no significant difference
(p> 0.05) on the total number of pyramidal cells between the control group (20.52 ± 1.31), the
ethanol group (19.02 ± 1.60), and the vitamin D3 group (21. 06 ± 0.70) per field of view.
However there was a significant increase (p<0.05) in the percentage of apoptotic CA1
hippocampal pyramidal cells in in the ethanol group (16.09 ± 0.67%) compared to the control
group (10.60 ± 0.95%). Vitamin D3 significantly (p<0.05) prevented an increase in the percentage
of apoptotic CA1 hippocampal pyramidal cells in the vitamin D3 group (10.82 ± 0.64%). In
conclusion, vitamin D3 had a neuroprotective effect to prevent an increase in apoptosis in CA1
hippocampal pyramidal cells to the neurotoxic effects induced by ethanol.