Immune Response Activation and Hepatoprotective Activity of Randia echinocarpa Soluble Melanins in Murine Models

This research demonstrates the in vivo immunomodulatory and hepatoprotective activities of the soluble melanins of the Randia echinocarpa fruit (PSM). The splenocyte cellular metabolic activity and lymphocyte T γδ expression in mesenteric lymph nodes (MLNs) and Peyer patches (PPs) were measured in the mice model. The PSM hepatoprotective activity was evaluated in the CCl₄-induced acute hepatotoxic injury (AHTI) in the rat model. Compared with the controls, the PSM treatment induced higher splenocyte cellular metabolic activity (in vitro, 24.1%-57.25%; in vivo, 28.8%-47.7%), activation of lymphocytes T γδ in MLN but suppression in PP. Related to in vivo hepatoprotective activity, PSM treatment reduces CCl₄-induced damage; animals showed lower levels of serum ALT (218.85-67.02 U/L) and ALP (453.37-355.47 U/L), higher levels of serum GSH (127.96-252.15 ng/mg of tissue), lower levels of hepatic MDA (10.25-7.85 nmol/mL), and less severe damage in the hepatic histopathology. These results suggest the nutraceutical and therapeutic potential of PSM.