Brown rice γ-oryzanol extracts attenuate IL-17/IL-10-mediated inflammation in liver, adipose tissue, and kidney of hypercholesterolemic rats: immunohistochemistry and molecular docking

This study evaluated the immunomodulatory effects of γ-oryzanol-rich brown rice extracts on IL-17/IL-10-mediated inflammation in the adipose tissue, liver, and kidneys of hypercholesterolemic rats. Molecular docking was performed to investigate the potential interaction of γ-oryzanol with the TLR4/NF-κB inflammatory pathway. Male Sprague-Dawley rats (n = 48) were allocated to normal and hypercholesterolemic conditions and subsequently assigned to untreated, γ-oryzanol, Black Madras (BM), and Universitas Brawijaya (UB) of brown rice γ-oryzanol extract. The extracts and γ-oryzanol were administered at 50 or 100 mg/kg BW for 28 consecutive days. Animal models of hypercholesterolemia significantly increased IL-17 expression and the IL-17/IL-10 ratio in visceral adipose, liver, and kidney. Administration of γ-oryzanol significantly decreased the IL-17/IL-10 ratio, indicating suppression of pro-inflammatory dominance and enhancement of anti-inflammatory signaling. The anti-inflammatory effects of γ-oryzanol were dose- and variety-dependent and were most pronounced in adipose tissue, reflecting tissue-specific immunomodulatory sensitivity. γ-oryzanol interacted with the catalytic site of TLR4 and the allosteric site of NF-κB, exhibiting stronger predicted interactions with lower binding affinities compared with the control ligands. These results indicated that γ-oryzanol from brown rice can regulate the inflammatory balance in visceral adipose, liver, and kidney in hypercholesterolemic conditions.