Bulbophyllum drymoglossum Aqueous Extract Modulates Immunometabolism and Oxidative Stress in Porcine Alveolar Macrophages.

Objective: This study aimed to evaluate the regulatory effects of Bulbophyllum drymoglossum aqueous extract (BDAE) on oxidative stress, mitochondrial function, and metabolic reprogramming in porcine alveolar macrophages.

Methods: BDAE was prepared by aqueous extraction and chemically characterized by GC-MS. Cytotoxicity and antioxidant properties were assessed in NIH/3T3 and 3D4/31 cells using viability assays, flow cytometry, and fluorescence imaging. Mitochondrial mass and membrane potential were measured by MitoTracker Red and JC-1 staining. Metabolic effects on glucose uptake, lipid accumulation, and gene expression related to fatty acid metabolism and mitochondrial respiration were analyzed by flow cytometry and quantitative RT-PCR.

Results: BDAE exhibited low cytotoxicity and effectively reduced intracellular reactive oxygen species under both basal and inflammatory conditions. It preserved mitochondrial membrane potential and prevented PMA-induced mitochondrial dysfunction. BDAE reversed PMA-triggered metabolic alterations by restoring glucose uptake, enhancing expression of genes involved in fatty acid β-oxidation, lipogenesis, and mitochondrial respiratory complexes, and attenuated lipid accumulation in macrophages. The extract's chemical profile, rich in carbohydrate derivatives and polyols, correlated with these bioactivities.

Conclusion: BDAE demonstrates potent antioxidative and metabolic regulatory effects in macrophages, suggesting its potential as a natural bioactive compound to modulate immunometabolism and oxidative stress in animal health. Further in vivo validation and mechanistic studies are warranted to advance its application in livestock production.