Protective Effect of Red Okra (Abelmoschus esculentus (L.) Moench) Pods against Sodium Nitrite-Induced Liver Injury in Mice

Abstract

Vegetables, drinking water, and preserved meats may contain sodium nitrite (NaNO₂), which causes liver disease by inducing oxidative stress. Phytochemicals are highly recommended as an alternative to synthetic drugs and affordable medicines to treat liver disease because they have fewer or no side effects. Therefore, this study aims to determine the antioxidant and hepatoprotective potential of red okra fruit ethanol extract against NaNO₂-induced liver damage. Thirty-six male mice were separated into six groups. The normal control group (WA) was given distilled water only, and the NaNO₂ (SN) group was given only 50 mg/kg BW NaNO₂. The other four groups (P1, P2, P3, and P4) were given NaNO₂ and red okra ethanol extract at doses of 25, 50, 75, and 100 mg/kg BW, respectively. Gavage was administered orally for 21 consecutive days. Commercial kits define all biochemical parameters according to the manufacturer's instructions. Liver tissue staining followed standard protocols using hematoxylin and eosin. The study revealed that NaNO₂ induction causes oxidative stress and damages the liver. The activity of antioxidant enzymes (superoxide dismutase and catalase) significantly increased in the groups treated (P2-P4) with ethanol extract of red okra (p < 0.05). Besides, the oxidants (malondialdehyde, F2-isoprostanes, and nitric oxide) in the liver homogenate significantly decreased in the P4 group, which were given red okra ethanol extract (p < 0.05). Likewise, red okra pods decreased significantly for the serum biochemical parameters of liver damage (aspartate aminotransferase, alkaline phosphatase, and alanine aminotransferase) in the P3 and P4 groups (p < 0.05). Then, it led to a restoration of the histological structure compared to exposed mice (SN), as the pathological scores decreased significantly in the P3 and P4 groups (p < 0.05), as well as the number of the necrotic and swollen liver cells was reduced. Hepatocytes returned to normal. The results showed that the ethanol extract of red okra fruit could be helpful as an affordable medicine. It is an antioxidant and hepatoprotective agent to protect the liver from damage caused by NaNO₂.

Figure 1

Histopathological view of liver sections. (a) Mice were given water alone. (b) Mice were given NaNO₂ alone. (c–f) 25, 50, 75, and 100 mg/kg BW red okra pods extract and 50 mg/kg BW NaNO₂, respectively, using hematoxylin and eosin stain technique (×400). Green arrow: swollen cell, yellow arrow: necrotic cell, black arrow: normal cell, and blue arrow: inflammation. (a) WA. (b) SN. (c) P1. (d) P2. (e) P3. (f) P4.

Figure 2

The effect of ethanol extract from red okra pods on the percentage of necrotic (a), normal (b), and swollen (c) hepatocytes. WA: mice were given distilled water alone, SN: mice were given NaNO₂ only. P1, P2, P3, and P4: 25, 50, 75, and 100 mg/kg BW red okra pods extract and 50 mg/kg BW NaNO₂, respectively. Different superscript letters within each figure indicate a significant difference between the means (p < 0.05).