Thymoquinone Attenuates NF-κβ Signalling Activation in Retinal Pigment Epithelium Cells Under AMD-Mimicking Conditions.

Oxidative stress in retinal pigment epithelium (RPE) cells plays a key role in the development of age-related macular degeneration (AMD), a leading cause of vision loss in the elderly. Thymoquinone, a bioactive antioxidant from Nigella sativa, has shown promise in reducing cellular oxidative stress. In AMD, prolonged exposure to oxidative stress may activate the NF-κβ signalling pathway in RPE cells, contributing to chronic inflammation, and its regulation by thymoquinone remains understudied. This study investigates the effects of thymoquinone in TNFα-induced RPE cells exposed to AGEs to mimic ageing conditions relevant for AMD. Gene and protein expression levels of NF-κβ pathway markers (P65, pP65 and Iκβα) were measured using qPCR and Western blotting, and statistical analysis was performed using Student's t-test and one-way ANOVA. Thymoquinone pretreatment at 0.1 µM and 10 µM significantly reduced the expression of these markers in TNFα-stimulated RPE cells. Notably, AGE-exposed cells demonstrated a heightened response to thymoquinone compared to non-AGE-exposed controls. These findings suggest that thymoquinone modulates NF-κβ signalling and may serve as a potential adjuvant therapeutic agent for AMD.