Piper retrofractum ameliorates imiquimod-induced skin inflammation via modulation of TLR4 axis and suppression of NF-κB activity

Chronic inflammation is a significant concern due to its association with various pathological conditions. As a result, extensive research has been conducted to identify new natural products that can effectively treat acute inflammation, which has the potential to inhibit the chronic inflammation. In our study, we aimed to identify Indonesian medicinal plants with the ability to inhibit proinflammatory agents, specifically targeting NF-κB, a crucial regulator of gene transcription involved in the production of proinflammatory proteins/cytokines. Through a series of identification processes, we found that Piper retrofractum (Javanese chili) extract demonstrated promising inhibitory effects on NF-κB and proinflammatory molecules. Further investigation was conducted using a variety of assays, including reporter assay, viability test, ELISA, and Western blotting. The results revealed that the extract significantly reduced LPS, NO, COX-2, IL-6, IL-1, and NF-κB through the TLR4 axis. Notably, Piper retrofractum extract was found to enhance the survival of human keratinocytes by protecting them from cell death induced by TRAIL, a member of the TNF superfamily. Moreover, immunohistochemistry analysis in an Imiquimod-induced skin inflammation mice model showed downregulation of COX-2 and IL-1β expression upon treatment with the extract. In conclusion, our findings suggest that Piper retrofractum extract possesses anti-inflammatory properties by reducing proinflammatory cytokine production through inhibition of NF-κB signaling pathway. These promising results highlight the potential of Piper retrofractum extract as a candidate for future drug development in the clinical treatment of inflammation-related conditions, offering hope for the advancement of therapeutic interventions.

Tyrosinase Enzymes Activities and Sun Protection Factor of Ethanol Extract, Water Fraction, and n-Butanol Fraction of Chromolaena odorata L. Leaves

Background: The need for skincare is increasing. One of the indicators of skin health is the brightness of the skin tone. Tyrosinase enzymes can darken the skin color due to their activity against melanin biosynthesis. The skin color will also change when exposed to UV rays, and even at a more severe level, it can cause cancer. Aims: The purpose of this study was to determine the inhibitory activity of the tyrosinase enzyme and the SPF (Sun Protection Factor) value of ethanol extract, water fraction, and n-butanol fraction from Chromolaena odorata L. leaves. Methods: In this study, tests were carried out on ethanol extract, water fraction, and an n-butanol fraction of C. odorata leaves to inhibit tyrosinase enzyme activity based on percent inhibition and determination of inhibitory activity against UV light based on the SPF value. Determination of tyrosinase enzyme inhibitory activity using an ELISA reader was carried out by calculating the IC50 value with kojic acid as a positive control and measuring the SPF value using UV-Vis spectrophotometry. Result: The results showed that the IC50 value of the tyrosinase enzyme inhibitory activity test, kojic acid as a positive control was 24.85 µg/mL (very strong), ethanol extract samples, water fraction, and n-butanol fraction were 191 µg/mL (weak), 65.86 µg/mL (very strong), and 14.59 µg/mL (very strong), respectively. The SPF value, including minimal protection shown by the ethanol extract at a concentration of 60 µg/mL, the water fraction at a 120 µg/mL concentration, and the n-butanol fraction a concentration of 40 µg/mL. Conclusion: The ethanol extract, water fraction, and n-butanol fraction of the Chromolaena odorata L. had an inhibitory effect on the tyrosinase enzyme and sun protection capacity used as an ingredient in cosmetic preparations

Photoprotective and Inhibitory Activity of Tyrosinase in Extract and Fractions of Terminalia catappa L

BACKGROUND: Chronic exposure to ultraviolet (UV) radiation causes various skin damages. One of the most significant risks to skin occurrence is cancer and photoaging. Recent strategies for photoprotection have included incorporating natural sunscreens and antityrosinase. AIM: This study aimed to determine the sun protection factor (SPF) and inhibitory activity of tyrosinase of the extract and fractions of leaves of Terminalia catappa Linn. METHOD: The dried leaves were macerated with 96% ethanol and fractionated using n-hexane, ethyl acetate, and water. The extract and fractions were screened for their phytochemical profile, and tyrosinase inhibitory activity was evaluated and expressed as IC50. The photoprotective activity of extract and fractions were measured by a UV spectrophotometric. RESULTS: Among the tested samples, the ethyl acetate fraction showed ultraprotection on erythema transmission rate (%TE), sunblock on pigmentation transmission (%TP), and minimum protection on SPF. Ethyl acetate fraction showed the highest activity to inhibit tyrosinase (IC50 was 50.54±2.37 μg/mL). The phytochemical analysis of ethyl acetate fraction revealed the presence of phenolic and flavonoid compounds. CONCLUSION: This study’s findings revealed a higher tyrosinase inhibitor and sun protection capacity of ethyl acetate fraction of leaves of T. catappa and suitable to develop as a cosmetic agent.

Evaluation of Antioxidant Activity of Botto-Botto Leaf Fraction (Chromolaena Odorata L.) Using DPPH and ABTS Methods

BACKGROUND: Antioxidants are substances that can inhibit the oxidation process, so that they have a protective effect on cells from the dangers of free radicals. One of the plants that has activity as natural antioxidants is Botto-Botto leaves (Chromolaena odorata L.). AIM: This study aims to determine the antioxidant activity of the Botto-Botto leaf fraction using the DPPH and ABTS methods. METHODS: The leaves of Botto-Botto (Chromolaena odorata L.) obtained from Takalar District, South Sulawesi are sorted, dried and pollinated. The powder was immersed in 70% ethanol solvent and sonicated. Furthermore, the extraction was carried out by maceration method with 70% ethanol solvent and fractionated using water, n-hexane, and n-butanol as solvents and dried. The fractionation results were continued for antioxidant testing using the DPPH and ABTS methods. RESULTS: The n-butanol fraction of Botto-Botto leaves had the highest antioxidant activity, namely the strong active category. In the DPPH and ABTS methods, the n-butanol fraction has IC50 values of 33.535 μg / mL and 60.885 μg / mL, respectively. CONCLUSION: The DPPH and ABTS methods, the n-butanol fraction of botto-botto leaves have strong antioxidant activity compared to other fractions, namely the water fraction and the n-hexane fraction.