Asterias amurensis lipids enhance the immunity of immunosuppressed mice as sustainable marine-eco materials.

Starfish (Asterias amurensis) are important predators in the marine benthic environment, preying on mollusks and echinoderms. Their waste also causes significant environmental harm. However, starfish contain a variety of nutrients and biologically active compounds that require further investigation. To maintain marine ecosystems and address environmental waste, lipids were extracted from A. amurensis skin, and their immune-enhancing effects were evaluated in cyclophosphamide (CY)- induced immunosuppressive mice. A. amurensis lipids were combined with PEG 6000 (AA-PEG), which contains a high content of polyunsaturated fatty acids (PUFAs, 49.44%), primarily C20:5n3. Mice were administered various dosages of AA-PEG, ranging from 50 to 200 mg/kg body weight (BW) via oral delivery and CY injection. Results revealed that AA-PEG at 150 mg/kg BW promoted the recovery of cellular immune function in both splenocytes from the spleen and peritoneal macrophages, similar to the normal group. Administration of AA-PEG (50-150 mg/kg BW) gradually raised the spleen index (2.2-2.5 mg/g) and natural killer (NK) cell activity (91-102%), and enhanced ConA- or LPS-stimulated splenocyte proliferation. Subsets of T -lymphocytes (CD4 + and CD8+) does-dependently increased by AA-PEG. The phagocytic capacity (58-82%) and proliferation (69-98%) of peritoneal macrophages, which had been reduced by CY, were restored with AA-PEG. AA-PEG boosts immunity by promoting nitric oxide (NO) generation (84-103%). Furthermore, AA-PEG has been shown to increase immune-related cytokines in splenocytes and peritoneal macrophages, indicating a potential enhancement of Th1 and Th2 activity. These results suggest that AA-PEG restored the immune function of immunosuppressed mice and could be used as an effective immunomodulatory agent, which may play a crucial role in maintaining environmental sustainability.