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Background. Till date, there is no known antidote to cure diabetes mellitus despite the discovery and development of diverse pharmacotherapeutic agents many years ago. Technological advancement in natural product chemistry has led to the isolation of analogs of vitexin and isovitexin found in diverse bioresources. These compounds have been extensively studied to explore their pharmacological relevance in diabetes mellitus. Aim of the Study. The present review was to compile results from in vitro and in vivo studies performed with vitexin and isovitexin derivatives relating to diabetes mellitus and its complications. A systematic online literature query was executed to collect all relevant articles published up to March 2020. Results. In this piece, we have collected data and presented it in a one-stop document to support the multitargeted mechanistic actions of vitexin and isovitexin in controlling diabetes mellitus and its complications. Conclusion. Data collected hint that vitexin and isovitexin work by targeting diverse pathophysiological and metabolic pathways and molecular drug points involved in the clinical manifestations of diabetes mellitus. This is expected to provide a deeper understanding of its actions and also serve as a catapult for clinical trials and application research.

The accurate X-ray single-crystal structures of the isoflavone compounds 4-O-methylalpinumisoflavone, O,O-dimethylalpinumisoflavone and 5-O-methyl-4-O-(3-methylbut-2-en-1-yl)alpinumisoflavone {alpinumisoflavone = 5-hydroxy-7-(4-hydroxyphenyl)-2,2-dimethyl-2H,6H-benzo[1,2-b:5,4-b']dipyran-6-one} from data sets measured at cryogenic temperature have been obtained from invariom modelling using theoretically predicted Hansen and Coppens multipole-model form factors, which describe the aspherical electron density distribution. Molecular dipole moments and electrostatic potentials obtained from invariom modelling are discussed and compared with results from ab initio theoretical calculations. All three studied compounds are solvent extracts of root bark or seed powder of Millettia thonningii (leguminosae), a plant molluscicide and cercaricide used in Franco West Africa as medication against various diseases. The compounds' toxicities to brine shrimp have been determined and their different potencies tentatively related to conformation differences, intramolecular contacts, dipole moments and electrostatic potential features.

Resistance in malaria vectors is likely to be caused by the massive use of insecticides in agriculture. Anopheles gambiae s.l. collected from breeding grounds in two cabbage growing areas within Accra were assessed for levels of resistance to 0.75% permethrin, 0.05% deltamethrin, 5% malathion and 4% DDT using standard WHO susceptibility test kits. Pyrethroid and organophosphate residue levels in soil and runoff water from these cabbage farms were determined and possible association between resistance and residue levels were established. Compared to the susceptible 'Kisumu' strain, both Korle-Bu and Airport populations were highly resistant to DDT and gave resistance levels which were over nine-fold for permethrin and over 2.5-fold for deltamethrin. Both wild and susceptible populations showed full susceptibility to malathion. The S and M forms of A. gambiae s.s. were found to occur in sympatry in the two study sites with a higher frequency of S form in the Airport area. Toxicity testing of extracts of soil and runoff water from these cabbage farms, using brine shrimp lethality tests, showed high level of toxicity, indicative of the presence of residues of insecticides. Differential fractionation of these extracts using solid phase extractor (SPE) suggests that the bulk of residues in these extracts may be pyrethroids and organophosphates. No correlation was observed between either residue levels or residual bioactivity in soil and runoff water, and resistance levels in A. gambiae s.l. populations, collected from breeding grounds within the farms under investigation. It is proposed that resistance in A. gambiae larvae in these breeding sites contaminated with agricultural insecticides may have occurred over time due to continuous exposure to sub-lethal doses.

The structure‐activity relationships between five amides previously isolated from the root extract of Piper guineense Schum and Thonn were studied. The methyl‐terminated amides, pellitorine and kalecide, were found to be more polar and caused higher knockdown, but showed less lethal action against insects than their methylenedioxyphenyl‐terminated counterparts, pipercide and guineensine. Guineensinamide showed weak activity and this was correlated with higher unsaturation and the presence of a pyrrolidyl group in the molecule. There was an association between the polarity of the amides and the recovery of the insects from their effects, much more recovery being observed with the methylterminated than with the methylenedioxyphenyl‐terminated amides. Electrophysiological investigations of the effects of pellitorine and pipercide on miniature excitatory postsynaptic potentials (MEPSPs) from the locust retractor unguis nerve‐muscle preparation showed that the amides caused a reduction in both the frequency and amplitude of MEPSPs, pipercide being between 100 and 1000 times more effective than pellitorine. An action of the amides on presynaptic transmission is suggested. The effects of pipercide and pellitorine on the isolated nerve‐muscle preparation were correlated with the symptoms of poisoning at the whole animal level.