Dereplication and Quantification of Major Compounds of Convolvulus arvensis L. Extracts and Assessment of Their Effect on LPS-Activated J774 Macrophages.

Convolvulus arvensis is used in Pakistani traditional medicine to treat inflammation-related disorders. Its anti-inflammatory potential was evaluated on hexane, dichloromethane, ethyl acetate, methanol, and aqueous extracts of whole plant on pro-inflammatory mediators in LPS-activated murine macrophage J774 cells at the non-cytotoxic concentration of 50 µg/mL. Ethyl acetate (ARE) and methanol (ARM) extracts significantly decreased mRNA levels of IL-6, TNF-α, MCP-1, COX-2, and iNOS. Furthermore, both extracts dose dependently decreased IL-6, TNF-α, and MCP-1 secretion. Forty-five compounds were putatively identified in ARE and ARM by dereplication (using HPLC-UV-HRMSn analysis and molecular networking), most of them are reported for the first time in C. arvensis, as for example, nineteen phenolic derivatives. Rutin, kaempferol-3-O-rutinoside, chlorogenic acid, 3,5-di-O-caffeoylquinic acid, N-trans-p-coumaroyl-tyramine, and N-trans-feruloyl-tyramine were main constituents identified and quantified by HPLC-PDA in ARE and ARM. Furthermore, chlorogenic acid, tyramine derivatives, and the mixture of the six identified major compounds significantly decreased IL-6 secretion by LPS-activated J774 cells. The activity of N-trans-p-coumaroyl-tyramine is shown here for the first time. Our results indicate that ARE, ARM and major constituents significantly inhibited the expression of pro-inflammatory mediators, which supports the use of this plant to treat inflammatory diseases.

Chromametric assessment of drug skin tolerance: A comparative study between Africans and Caucasians skins.

BACKGROUND/AIMS: During dermatological forms development, one of the simplest non-invasive techniques used to evaluate cutaneous tolerance of formulations is to monitor the color changes using a tristimulus chromameter. Most published tolerance studies involving chromametric measurements are performed on Caucasian subjects. However, in the context of drug formulation for African-type populations, it is not always relevant to transpose tolerance results obtained on Caucasians populations to African-type ones due to histological ethnic differences of the skin. The goal of this work was to assess whether tristimulus chromameter can be used to highlight color variations following the application of dermatological topics on black skin in order to validate skin tolerance studies made on African-type subjects. MATERIALS AND METHODS: After application of two commercial creams with opposite side effects (skin irritation and skin blanching) in both Africans and Caucasians populations, color variations were evaluated using a tristimulus chromameter in L* a* b* color system and compared between both populations. L* indicating color brightness, a* represents green and red directions and b* represents blue and yellow directions. RESULTS: While skin irritation resulted in a significant increase of a* parameter in both studied populations, the skin blanching resulted in a decrease of a* associated with an increase of L* . CONCLUSION: We established that tristimulus chromameter can be used to achieve in vivo skin tolerance study of dermatologic formulations in Africans despite their dark skin even though it appeared less sensitive. This study can speed up the development of dermatological forms dedicated to Africans and/or Caucasians subjects.

Detection of Poor Quality Artemisinin-based Combination Therapy (ACT) Medicines Marketed in Benin Using Simple and Advanced Analytical Techniques.

BACKGROUND: Poor quality antimalarial medicines still represent a threat to the public health, especially in Sub-Saharan Africa which bears a disproportionate share of the global burden of malaria. It is essential and urgent to strengthen mechanisms against counterfeit medicines. One of the approaches is regular market surveillance through quality controls. METHODS: 12 samples of artemether/lumefantrine were collected from formal and informal drug sellers in Cotonou (Benin) as well as additional other similar samples from Rwanda (13 samples) and from D.R. Congo (9 samples). Thin Layer Chromatography (TLC) as classical and simple identification test was applied in Benin while an analytical chemistry laboratory in Belgium (ULg, Pharmacy Department) was asked for further analyses with HPLC and Raman spectroscopy using a developed and validated HPLC method for rapid analysis of artemether/lumefantrine. RESULTS: The results obtained in Belgium confirmed the lack of the two active ingredients in the suspected sample of ACT medicine from Benin whereas some samples from Rwanda and D.R. Congo were found to present risk of substandard drugs either for under-dosing or over-dosing. CONCLUSIONS: Counterfeit/falsified of artemisinin-based combination therapy (ACT) medicines are really scourge that needs to be fought through strong collaboration between public health authorities and appropriate quality control laboratories.