Antithrombotic and cytotoxic activities of four Bangladeshi plants and PASS prediction of their isolated compounds

Understanding the Artemia Salina (Brine Shrimp) Test: Pharmacological Significance and Global Impact

BACKGROUND

The microplate benchtop brine shrimp test (BST) has been widely used for screening and bio-guided isolation of many active compounds, including natural products. Although the interpretation given to the results appears dissimilar, our findings suggest a correlation between positive results with a specific mechanism of action.

OBJECTIVE

This study aimed to evaluate drugs belonging to fifteen pharmacological categories having diverse mechanisms of action and carry out a bibliometric analysis of over 700 citations related to microwell BST.

METHODS

Test compounds were evaluated in a serial dilution on the microwell BST using healthy nauplii of Artemia salina and after 24 hrs of exposition, the number of alive and dead nauplii was determined, and the LC50 was estimated. A metric study regarding the citations of the BST miniaturized method, sorted by type of documents cited, contributing country, and interpretation of results was conducted on 706 selected citations found in Google Scholar.

RESULTS

Out of 206 drugs tested belonging to fifteen pharmacological categories, twenty-six showed LC50 values <100 μM, most of them belonging to the category of antineoplastic drugs; compounds with different therapeutical uses were found to be cytotoxic as well. A bibliometric analysis showed 706 documents citing the miniaturized BST; 78% of them belonged to academic laboratories from developing countries located on all continents, 63% interpreted their results as cytotoxic activity and 35% indicated general toxicity assessment.

CONCLUSION

BST is a simple, affordable, benchtop assay, capable of detecting cytotoxic drugs with specific mechanisms of action, such as protein synthesis inhibition, antimitotic, DNA binding, topoisomerase I inhibitors, and caspases cascade interfering drugs. The microwell BST is a technique that is used worldwide for the bio-guided isolation of cytotoxic compounds from different sources.

Plant-Derived Compounds and Extracts as Modulators of Plasmin Activity-A Review

Functionality of the fibrinolytic system is based on activity of its central enzyme, plasmin, responsible for the removal of fibrin clots. Besides the hemostasis, fibrinolytic proteins are also involved in many other physiological and pathological processes, including immune response, extracellular matrix degradation, cell migration, and tissue remodeling. Both the impaired and enhanced activity of fibrinolytic proteins may result in serious physiological consequences: prothrombotic state or excessive bleeding, respectively. However, current medicine offers very few options for treating fibrinolytic disorders, particularly in the case of plasmin inhibition. Although numerous attempts have been undertaken to identify natural or to develop engineered fibrinolytic system modulators, structural similarities within serine proteases of the hemostatic system and pleiotropic activity of fibrinolytic proteins constitute a serious problem in discovering anti- or profibrinolytic agents that could precisely affect the target molecules and reduce the risk of side effects. Therefore, this review aims to present a current knowledge of various classes of natural inhibitors and stimulators of the fibrinolytic system being well-defined low-molecular plant secondary metabolites or constituents of plant extracts as well as plant peptides. This work also discusses obstacles caused by low specificity of most of natural compounds and, hence, outlines recent trends in studies aimed at finding more efficient modulators of plasmin activity, including investigation of modifications of natural pharmacophore templates.

A comprehensive multi-directional exploration of phytochemicals and bioactivities of flower extracts from Delonix regia (Bojer ex Hook.) Raf., Cassia fistula L. and Lagerstroemia speciosa L

Delonix regia (Bojer ex Hook.) Raf., Cassia fistula L. and Lagerstroemia speciosa L. are three ornamental plants that produce colorful flowers. The present study aimed to evaluate the phytochemicals and bioactivities of methanolic extracts of flowers from Delonix regia (DrFME), Cassia fistula (CfFME), and Lagerstroemia speciosa (LsFME). The presence of ten different chemical classes in varying degrees was confirmed while qualitatively screened. During quantitative determination, LsFME possesses the highest amount of total phenolic (418.0 mg/g), flavonoid (50.8 mg/g), and tannin (256.3 mg/g) contents. The extracts showed excellent antioxidant capacity in a concentration-dependent manner with the lowest IC50 value (41.51 μg/mL) displayed by LsFME. LsFME paralyzed the experimental worms at 2.95 min and killed at 3.96 min. DrFME was found to be more effective in thrombolytic (35.5% clot lysis) and anticoagulant activities. Negligible hemolytic activity (IC50 > 200 μg/mL) found for all extracts which suggest their less potential toxicity. The in vivo experiments revealed that the CfFME has the highest analgesic (64.34% pain inhibition) activity while LsFME has the highest antidiarrheal (70.27% inhibition) and antihyperglycemic (46.94% inhibition) activities at 400 mg/kg of body weight doses. This study has shown the presence of phytochemicals and potential bioactivities which indicates the possibility of these flowers to be used as a source of phytochemicals as well as safe and effective natural medicine.

Curculigo recurvata W.T.Aiton exhibits anti-nociceptive and anti-diarrheal effects in Albino mice and an in silico model

BACKGROUND

Curculigo recurvata (C. recurvata) is an enthnomedicinally important herb reported to have significant medicinal values. The present study aimed to explore the in vivo and in silico anti-nociceptive and anti-diarrheal effects of a C. recurvate rhizome methanol extract (Me-RCR).

METHODS

The analgesic effects of Me-RCR were assessed using acetic acid-induced writhing and the formalin-induced flicking test. The drugs were administered intraperitoneally (IP) at doses of 200 and 400 mg/kg body weight (bw). Anti-diarrheal activity was evaluated by assessing intestinal motility, hypersecretion, and fecal score in mice at oral doses of 200 and 400 mg/kg·bw. Computer facilitated analyses for anti-nociceptive and anti-diarrheal activities of three isolated compounds from C. recurvata were undertaken to identify the best-fit phytoconstituents.

RESULTS

The Me-RCR showed significant (P < .05) peripheral anti-nociception at the highest dose. The extract inhibited both early and late phases of nociception in the formalin-induced writhing test. In the castor oil-induced diarrhoea model, the extract significantly (P < .05) prolonged the onset time of diarrhoea, inhibited percentage of diarrhoea, and decreased both the volume and weight of intestinal contents. Rates of intestinal fluid accumulation inhibition were (33.61 ± 1.00)% and (46.44 ± 0.89)% at Me-RCR doses of 200 and 400 mg/kg·bw, respectively. Moreover, a significant (P < .05) reduction in gastrointestinal motility was observed. An absorption, distribution, metabolism, excretion and/or toxicity (ADME/T) test showed that the selected compounds yielded promising results, satisfying Lipinski's rule of five for predicting drug-like potential. Notably, of the three phytoconstituents curculigine and isocurculigine possessed the highest affinity for the COX-1 and COX-2. Isocurculigine was also identified as the most effective anti-diarrheal compound in the computer-facilitated model.

CONCLUSION

An extract of the plant C. recurvata showed potential analgesic and anti-diarrheal activity due to the presence of one or more active secondary metabolite(s).