Limonene-Based Solid Lipid Nanoparticles for Psoriasis: A Novel Phyto therapeutic Approach

AbstractPsoriasis is a chronic, immune-mediated inflammatory skin disorder characterized by hyperproliferation ofkeratinocytes and dysregulation of key inflammatory pathways, particularly TNF-α, IL-17, and IL-23. Affectingapproximately 2–3% of the global population, the disease presents in multiple clinical forms, with plaque psoriasisbeing the most prevalent. In addition to cutaneous manifestations, psoriasis is frequently associated with systemiccomorbidities such as metabolic syndrome, cardiovascular disorders, and psoriatic arthritis. Althoughconventional treatments—including topical corticosteroids, vitamin D analogues, phototherapy, systemicimmunosuppressants, and biologics—provide symptomatic relief, their long-term use is often limited byinadequate skin penetration, systemic toxicity, adverse effects, and reduced patient adherence.Nanotechnology-based drug delivery systems have emerged as promising alternatives to overcome thesetherapeutic limitations. Nanoparticles enhance dermal drug penetration, improve bioavailability, providecontrolled and sustained release, and reduce systemic exposure. Among various nanocarriers, solid lipidnanoparticles (SLNs) have gained considerable attention due to their biocompatibility, occlusive properties,targeted drug delivery capability, and improved stability of encapsulated agents. Incorporation of bioactive phytoconstituents such as limonene and quercetin further strengthens the therapeutic potential through anti-inflammatory and antioxidant mechanisms.