Natural Products Targeting Immune Mechanisms in Ocular Inflammation: Uveitis and Dry Eye.

At present, the clinical management of ocular inflammatory diseases predominantly relies on chemically synthesized therapeutic agents. Although these therapies demonstrate established efficacy, their long-term use is associated with substantial economic burden. In addition, they may cause ocular side effects and systemic adverse reactions involving the cardiovascular, hepatic, and renal systems. In contrast, natural products have attracted increasing attention in recent years because many are accessible, relatively cost-effective, and potentially well tolerated. Studies indicate that various natural products exert anti-inflammatory and immunomodulatory effects by inhibiting inflammatory signaling pathways such as NF-κB and MAPK, regulating immune cell function and alleviating oxidative stress responses. These multifunctional properties support their potential therapeutic value in various inflammatory diseases. Notably, several natural products have shown potential benefits in clinical trials; however, their investigation and application in ocular diseases remain relatively limited. In this review, we focus on uveitis and dry eye disease (DED) as representative ocular disease models and systematically summarize the current research progress on four natural products-Paeonia lactiflora extracts, resveratrol and its derivatives, curcumin, and boswellic acids in experimental studies of ocular diseases. We particularly focus on their effects in alleviating ocular surface inflammation and intraocular inflammatory responses through their immunomodulatory mechanisms. This review aims to provide a mechanistic framework for understanding the potential role of natural products as complementary or alternative strategies to current therapeutic approaches, while informing the development of novel therapeutics and future research directions in ocular diseases.