Alkaloids in Erythrina by UPLC-ESI-MS and In Vivo Hypotensive Potential of Extractive Preparations

Amazonia Phytotherapy Reduces Ischemia and Reperfusion Injury in the Kidneys

Acute kidney injury (AKI) is defined as a sudden decrease in kidney function. Phytomedicines have shown positive effects in the treatment of AKI worldwide. The aim of this study was to evaluate the effect of Abuta grandifolia on the renal function of rats submitted to AKI. A phytochemical study of the plant was performed through liquid chromatography coupled with mass spectrometry (CL-EM) and DPPH and ABTS antioxidant tests. Renal function tests were performed in 20 male adult Wistar rats weighing from 250 to 300 g distributed in the following groups: SHAM (submitted to laparotomy with simulation of renal ischemia); ABUTA (animals that received 400 mg/kg of AG, orally-VO, once a day, for 5 days, with simulation of renal ischemia); I/N (animals submitted to laparotomy for clamping of bilateral renal pedicles for 30 min, followed by reperfusion); ABUTA + I/R (animals that received AG-400 mg/kg, 1× per day, VO, for 5 days, submitted to renal ischemia after treatment with herbal medicine). The results suggest that the consumption of Abuta grandifolia promoted renoprotection, preventing the reduction of renal function induced by ischemia, oxidizing activity, and deleterious effects on the renal tissue, confirmed by the decrease of oxidative metabolites and increase of antioxidants in the animals' organisms.

Computational studies of biologically active alkaloids of plant origin: an overview

Computational studies nowadays constitute a crucial source of information for drug development, because they provide information on many molecular properties and also enable predictions of the properties of not-yet-synthesized compounds. Alkaloids are a vast group of natural products exhibiting a variety of biological activities, many of which are interesting for drug development. On the other hand, computational studies of biologically active alkaloids have so far mostly focused on few particularly relevant or “popular” molecules, such as quinine, caffeine, or cocaine, with only few works on the other molecules. The present work offers an overview of existing computational studies on alkaloid molecules, from the earliest ones to the most recent, and considering all the theoretical approaches with which studies have been performed (both quantum mechanics and molecular dynamics). The considered studies are grouped according to their objectives and outcomes, such as conformational analysis of alkaloid molecules, effects of selected solvents on their properties, docking studies aimed at better understanding of the interactions between alkaloid molecules and biological targets, studies focusing on structure activity relationships, and computational studies performed to confirm experimental results. It is concluded that it would be important that computational studies on many other alkaloid molecules are performed and their results made available, covering their different classes as well as the variety of their biological activities, to attain better understanding of the properties not only of individual molecules, but also of groups of related molecules and of the overall alkaloids family.

Gastroprotective effects of Erythrina speciosa (Fabaceae) leaves cultivated in Egypt against ethanol-induced gastric ulcer in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Members of the genus Erythrina have been traditionally used in the treatment of various ailments such as inflammation and gastrointestinal disorders. Erythrina speciosa (Fabaceae) is a spiny, deciduous shrub or small tree native to Southern America in Brazil. It is cultivated in Africa and Asia. The traditional usage of E. speciosa indicated its antibacterial, analgesic, and anti-inflammatory activities.

AIM OF THE STUDY

Evaluation of the phytochemical constituents, gastroprotective effects and possible mechanism of action of the ethyl acetate fraction obtained from the methanol extract of E. speciosa leaves (ESLE).

MATERIALS AND METHODS

Chemical characterization of ESLE was done using high performance liquid chromatography coupled to mass spectrometry (HPLC-MS). The gastroprotective activity of ESLE was evaluated using ethanol-induced gastric-ulcer model in rats. Rats were pre-treated with ESLE 25, 50 and 100 mg/kg 1 h before the administration of absolute ethanol. Histological analysis, mucin content, and total acidity were evaluated. The possible mechanism of action of ESLE was studied through the examination of oxidative stress and inflammatory markers, PGE2, and NF-κB, iNOS, COX-2, and HSP-70 immunoexpression. In vitro, anti-Helicobacter pylori activity of ESLE was also studied using micro-well dilution method.

RESULTS

Fourteen compounds were tentatively identified including alkaloids, flavonoids, and saponins. ESLE exerted a powerful gastroprotective effect. The pre-treatment with ESLE at different doses resulted in a significant reduction in gastric lesions and significant elevation in the mucin production. These effects could be partially mediated by the potent anti-inflammatory activity of ESLE as evidenced by the significant reduction in the immunoexpression of NF-κB, COX-2, iNOS and the reduction in the pro-inflammatory marker, TNF-α. ESLE counteracted the ethanol-induced oxidative stress by increasing the levels of depleted GSH and catalase as well as significantly attenuating the ethanol-induced lipid peroxidation tissue levels. In addition, ESLE exhibited in vitro antibacterial activity against H. pylori.

CONCLUSIONS

The chemical constituents of ESLE strongly support its potent gastroprotective effect suggesting its future potential application in the management of gastric ulcer by eliminating its symptoms and causes including H. pylori.

The genus Erythrina L.: A review on its alkaloids, preclinical, and clinical studies

Erythrina L. genus (Fabaceae) comprises about 115 species, and it has been extensively studied, mainly because of its alkaloids, which have pharmacological properties. References demonstrated that Erythrina spp. have a potential to act in the central nervous system, presenting anxiolytic and anticonvulsant properties already established. Phytochemical investigations confirmed the presence of tetracyclic alkaloids as the major compounds. However, other alkaloid classes have also been reported, including dimeric and trimeric substances, coupled through direct polymerization or two erythrinine units via an acetyl glucose. The present review covers the relevant literature from 1990 until 2017 and outlines the current data on chemical composition and preclinical and clinical studies on Erythrina species. Additionally, the quite striking analogy in the biosynthetic route of erythrin, morphinans, and Amaryllidaceae family alkaloids was also discussed.