Pulp Callus Extract From Malus domestica var. Mela Rosa Marchigiana Preserves Intestinal Barrier Integrity and Confers Neuroprotection in a Gut–Brain Axis Co‐Culture Model
Alessandro Nicois, Daniele Fraternale, Francesco Palma, Brenda Marfella, Giuditta Fiorella Schiavano, Mariastella Colomba, Armando Gregorini, Barbara Di Giacomo, Luigia Cristino, Vincenzo Di Marzo, Maria Cristina Albertini, Letizia PalombaABSTRACT
The gut–brain axis is a key target in neuroinflammatory disorders. We investigated the protective effects of Mela Rosa Marchigiana pulp callus extract (MRME), a phytocomplex with a unique triterpenic profile. Using a validated transwell co‐culture model of the intestinal‐neural interface, differentiated Caco‐2 cells formed a polarized epithelial barrier (apical), while BV2 microglia or SH‐SY5Y neurons were seeded in the basolateral compartment. Apical MRME pretreatment preserved Caco‐2 barrier integrity against lipopolysaccharide or dextran sodium sulfate‐induced damage. MRME maintained occludin integrity and transepithelial electrical resistance (TEER), effectively neutralizing “leaky gut”‐like conditions. By stabilizing the barrier, MRME exerted indirect neuroprotection since high‐throughput live‐cell imaging revealed dose‐dependent reductions in reactive oxygen species generation and apoptosis (caspase‐3/7 activation) in both BV2 and SH‐SY5Y cells. MRME demonstrated a microbiologically neutral profile, exerting no inhibitory effects on either pathogenic or probiotic strains up to 10,000 μg/mL. MRME provides dual protection by strengthening the intestinal barrier and shielding the neural environment from systemic inflammation through host cellular modulation rather than microbial interference. These findings suggest MRME as a promising nutraceutical candidate for gut–brain axis dysregulation.