Photoprotective and anti-inflammatory potential of Tagetes erecta L. from southern coastal region of Pakistan: A study on psoriasis-prone skin.

BACKGROUND

Psoriasis represents a chronic autoimmune dermatosis that necessitates the implementation of both anti-inflammatory measures and UVA-UVB photoprotection.

OBJECTIVES

This study aimed to evaluate the phytochemical profile, antioxidant capacity , photoprotective efficacy, and anti-inflammatory potential of Tagetes erecta flower extracts (TEFE) prepared in different solvents.

METHODS

In this study phytochemical analysis and antioxidant properties were performed in various solvent extracts of Tagetes erecta flowers. Photoprotective efficacy was assessed using critical wavelength (λc) and SPF measurements under different exposure conditions. Anti-inflammatory activity was evaluated via heat-induced protein denaturation, heat-induced hemolysis, and hypotonicity- induced hemolysis assays.

RESULTS

The result indicated that TEFE contain all the secondary metabolites known for their skin-protective properties. The highest TPC was observed in the methanolic and ethyl acetate extracts, measuring (0.7733 ± 0.0024 and 0.7729 ± 0.0007 mg GAE/mg), respectively. The acetone and ethanolic extracts exhibited the highest flavonoid contents (17.553 ± 0.1064 and 14.904 ± 0.506 mg Rutin/mg) and flavanol contents (4.279 ± 0.268 and 3.829 ± 0.1002 mg Rutin/mg), respectively. At all concentrations, TEFE exhibited λc greater than 370 nm, indicating broad-spectrum photoprotective properties. At 800 ppm, TEFE demonstrated SPF values of 29 without exposure, while SPF of 40.2 under sunlight and 32.80 under UV exposure were measured. The Statistical analysis revealed significant differences in photoprotective activity across all tested concentrations (P<0.05).TEFE showed considerable inhibition of protein denaturation, with IC50 = 527.845 µg/mL and exhibited concentration-dependent membrane stabilization, with a maximum inhibition of 69% in heat-induced RBC lysis and 22% in hypotonicity-induced RBC lysis.

CONCLUSION

These results advocate for a novel phototherapeutic strategy for addressing photoprotection in psoriatic skin and require further clinical research in dermatological preparations.