Immune dysregulation and autoreactivity correlate with disease severity in SARS-CoV-2-associated multisystem inflammatory syndrome in children

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The chemistry and pharmacology of alkaloids and allied nitrogen compounds from Artemisia species: A review

Several reviews have been published on Artemisia's derived natural products, but it is the first attempt to review the chemistry and pharmacology of more than 80 alkaloids and allied nitrogen compounds obtained from various Artemisia species (covering the literature up to June 2018). The pharmacological potential and unique skeleton types of certain Artemisia's alkaloids provoke the importance of analyzing Artemisia species for bioactive alkaloids and allied nitrogen compounds. Among the various types of bioactive Artemisia's alkaloids, the main classes were the derivatives of rupestine (pyridine–sesquiterpene), lycoctonine (diterpene), pyrrolizidine, purines, polyamine, peptides, indole, piperidine, pyrrolidine, alkamides, and flavoalkaloids. The rupestine derivatives are Artemisia's characteristic alkaloids, whereas the rest are common alkaloids found in the family Asteraceae and chemotaxonomically links the genus Artemisia with the tribes Anthemideae. The most important biological activities of Artemisia's alkaloids are including hepatoprotective, local anesthetic, β‐galactosidase, and antiparasitic activities; treatment of angina pectoris, opening blocked arteries, as a sleep‐inducing agents and inhibition of HIV viral protease, CYP450, melanin biosynthesis, human carbonic anhydrase, [3H]‐AEA metabolism, kinases, and DNA polymerase β¹. Some of the important nitrogen metabolites of Artemisia include pellitorine, zeatin, tryptophan, rupestine, and aconitine analogs, which need to be optimized and commercialized further.     

Phytochemical and antitrypanosomal investigation of the fractions and compounds isolated from Artemisia elegantissima

Context: Trypanosoma brucei brucei (T.b. brucei) infection causes death in cattle, while the current treatments have serious toxicity problems. However, natural products can be used to overcome the problems associated with parasitic diseases including T.b. brucei.

Objective: Artemisia elegantissima Pamp (Asteraceae) was evaluated phytochemically for its constituents and antitrypanosomal potential against T.b. brucei for the first time. Scopoletin isolated from A. elegantissima has shown better potential then the standard drug suramin, used against T.b. brucei.

Materials and methods: The ethanol extract of the aerial parts of A. elegantissima was fractionated by column and preparative thin-layer chromatography into six fractions (A–F) yielding 13 compounds, these were evaluated for their antitrypanosomal activity against T.b. brucei at different concentrations.

Results: Thirteen compounds were isolated from A. elegantissima: (Z)-p-hydroxy cinnamic acid, stigmasterol, β-sitosterol, betulinic acid, bis-dracunculin, dracunculin, scopoletin, apigenin, dihydroluteolin, scoparol, nepetin, bonanzin, and 3′,4′-dihydroxy bonanzin. The fractions D–F were found to be active at the concentration of 20?µg/ml and three compounds isolated from these fractions, scopoletin (MIC?≤0.19?µg/ml), 3′,4′-dihydroxy bonanzin (MIC?=?6.25?µg/ml) and bonanzin (MIC?=?20?µg/ml), were found to be highly active.

Discussion and conclusion: Artemisia elegantissima was phytochemically and biologically explored for its antitrypanosomal potential against T.b. brucei. The number and orientation of phenolic hydroxyl groups play an important role in the antitrypanosomal potential of coumarins and flavonoids. The compounds 3′,4′-dihydroxy bonanzin and scopoletin with low MIC values, hold potential for use as antitrypanosomal drug leads.