Ameliorative effects of Dictyota dichotoma on hepatotoxicity induced by gibberellic acid in albino rats.

Gibberellic acid (GA3) is a natural plant growth regulator that is crucial for plant structural and functional development. We examined the alleviating capacity of brown algae (Dictyota dichotoma) on biochemical and molecular degenerative processes caused by sub-chronic exposure to gibberellic acid resulting in hepatic cell apoptosis. Adult male albino rats were divided into five equal groups: the first group received distilled water, the second group was treated with GA3, the third group was administered D. dichotoma extract suspended in 1% carboxymethylcellulose (CMC), the fourth group was administered both GA3 and D. dichotoma simultaneously, and the fifth group received 1% CMC orally, 5 days per week for a total of 50 days. The results indicated that GA3 induced a significant increase in liver function parameters based on serum levels of alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and albumin, which indicate hepatotoxicity. A marked increase in malondialdehyde (MDA) levels and a marked decrease in reduced glutathione (GSH), glutathione-S-transferase (GST), and superoxide dismutase (SOD) were observed as a result of induction of lipid peroxidation and oxidative stress. Histopathology revealed severely degenerated hepatocytes including cytoplasmic vacuolations and many apoptotic cells with weak Bcl2 expression. Similarly, there was a significant up-regulation of gene and protein expression levels for the pro-apoptotic markers, Caspase-3 and Bax, and an increase in pro-inflammatory marker levels, tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) as well as C-reactive protein (CRP). The co-administration of D. dichotoma restored the disrupted biochemical, histopathological, molecular, and inflammatory changes resulting from GA3 toxicity. Our results confirm the antioxidant, anti-inflammatory, anti-apoptotic, and hepatoprotective potential of D. dichotoma.