Phytochemical Gut Axis: Potential of Cestrum nocturnum to Modulate Gut Barrier Integrity and Inflammation

Background: Intestinal epithelial barrier dysfunction is a critical factor in gastrointestinal and metabolic disorders, primarily driven by disruption of tight junction (TJ) proteins such as ZO-1, occludin, and claudins. Aim: This review aims to evaluate the phytochemical composition of Cestrum nocturnum and its potential role in modulating gut barrier integrity and inflammation. Methods: A comprehensive literature review was conducted focusing on phytochemicals of C. nocturnum and mechanistic studies of structurally similar flavonoids and phenolic compounds influencing epithelial barrier function. Results: C. nocturnum contains flavonoids, phenolic acids, saponins, and terpenoids with established antioxidant and anti-inflammatory properties. Mechanistic evidence from flavonoids such as quercetin and apigenin demonstrates enhancement of TJ protein expression, inhibition of NF-κB and MAPK signalling pathways, reduction in oxidative stress, and stabilisation of cytoskeletal architecture, thereby improving epithelial barrier integrity. Conclusion: Although direct experimental studies on C. nocturnum are limited, its phytochemical profile strongly supports its potential as a gut barrier-modulating agent. Further in vitro and in vivo validation is required. Major Findings: C. nocturnum contains bioactive phytochemicals capable of modulating oxidative stress and inflammatory signalling, which may stabilise tight junction proteins and improve intestinal barrier function.