The Hepatic Innate Immune Compartment after Aqueous Sorghum bicolor Leaf Sheath Extract: A Histomorphological Assessment of Kupffer Cell Prominence in Male Wistar

Abstract

The liver is a frontline immunological organ, and Kupffer cells, its resident macrophages, are the principal sentinels of hepatic innate immunity. Sorghum bicolor leaf sheaths are rich in polyphenols with reported antioxidant, anti-inflammatory and immune-modulating activity, yet how an aqueous extract of this material affects the hepatic immune compartment in vivo at the level of tissue architecture is not well described. This study evaluated the hepatic histomorphological response to aqueous S. bicolor leaf sheath extract in male Wistar rats, with attention to Kupffer cell prominence and parenchymal integrity. Dried leaf sheaths were extracted in distilled water, and twenty-four rats were assigned to four groups of six. The control group received 0.5 mL distilled water, while the other groups received 30.8, 23.1 and 15.4 mg/kg of the extract for fourteen days. Liver tissues were processed and stained with haematoxylin and eosin for histological evaluation. No hepatotoxic or degenerative changes were observed in any group, and hepatocytes, sinusoids and portal tracts appeared normal throughout. The principal finding was a mild increase in Kupffer cell prominence across the extract-treated groups relative to the control group, with mild sinusoidal and vascular dilation and focal vascular congestion at the lower doses. These observations indicate preserved hepatic architecture without inflammatory injury. The increased prominence of sinusoidal cells morphologically consistent with Kupffer cells may reflect activation, hyperplasia or recruitment of hepatic macrophages, which cannot be distinguished on routine haematoxylin and eosin staining. Immunohistochemical phenotyping and cytokine profiling are recommended to characterise this response further.