Understanding the (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.

Pharmacognostic Evaluation of Ten Species of Medicinal Importance of Cecropia: Current Knowledge and Therapeutic Perspectives.

This work covers a systematic review of literature about the genus from 1978 to 2020, emphasizing the analysis of 10 of the most relevant species and their associated biological activities. is a neotropical genus, which comprises about 61 native species in the American continent where it is known to be part of the traditional medicine of numerous countries. Secondary metabolites described for this genus showed an elevated structural and functional diversity, where polyphenols have been the most abundant.

Validation of an UPLC-DAD Method for the Quantification of Phenolic Acids, Verbascoside and 6-epi-aucubin in Crescentia cujete Fruit.

Background: The fruit pulp decoction of Crescentia cujete, commonly known as calabash, is traditionally used for the treatment of several respiratory diseases and is available as syrup formulations. Unfortunately, there is no detailed investigation on the analytical methods for warranting the quality of these products.

Aims And Objectives: To develop and validate an appropriate analytical method for the simultaneous quantification of trans-cinnamic acid, 4-hydroxybenzoic acid, verbascoside and 6- epi-aucubin in the decoction and commercial cough syrups of Crescentia cujete fruit.

Simulated Gastrointestinal Biotransformation of Chlorogenic Acid, Flavonoids, Flavonolignans and Triterpenoid Saponins in Cecropia obtusifolia Leaf Extract.

It is well known that biotransformation processes in the human body are crucial to form potentially bioactive metabolites from particular classes of natural products. However, little research has been conducted concerning the bioavailability of polyphenols, especially in the colon. The gastrointestinal stability and colonic biotransformation of the crude extract of the leaves of , rich in flavone -glycosides, was investigated under conditions, and the processing and interpretation of results were facilitated by using an automated machine learning model.

Image mean square displacement to study the lateral mobility of Angiotensin II type 1 and Endothelin 1 type A receptors on living cells.

The lateral mobility of membrane receptors provides insights into the molecular interactions of protein binding and the complex dynamic plasma membrane. The image mean square displacement (iMSD) analysis is a method used to extract qualitative and quantitative information of the protein diffusion law and infers how diffusion dynamic processes may change when the cellular environment is modified. The aim of the study was to describe the membrane diffusing properties of two G-protein-coupled receptors namely Angiotensin II type 1 (AT ) and Endothelin 1 type A (ET ) receptors and their corresponding receptor-ligand complexes in living cells using total internal reflection fluorescent microscopy and iMSD analysis.

Number and brightness analysis to study spatio-temporal distribution of the angiotensin II AT and the endothelin-1 ET receptors: Influence of ligand binding.

The angiotensin II AT and the endothelin 1 ET receptors play a crucial role in the pathogenesis of cardiovascular diseases like hypertension, heart failure, stroke, pulmonary hypertension, and cardiac hypertrophy. Both receptors are members of the rhodopsion-like superfamily of G protein-coupled receptors which can exist as monomers, dimers, and higher order aggregates. Recently, oligomerization of these two receptors have been described by several biophysical methods based mainly on luminescence and fluorescence energy transfer.

Ultrasound-assisted extraction optimization and validation of an HPLC-DAD method for the quantification of polyphenols in leaf extracts of Cecropia species.

Cecropia species are traditionally used in Latin American folk medicine and are available as food supplements with little information warranting their quality. The optimum conditions for the extraction of chlorogenic acid (CA), total flavonoids (TF) and flavonolignans (FL) from leaves of Cecropia species were determined using a fractional factorial design (FFD) and a central composite design (CCD). A reversed-phase high-performance liquid chromatographic method coupled to a diode array detector (HPLC-DAD) was validated for the quantification of CA, TF and FL, following the ICH guidelines.

Phytochemical characterization and comparative studies of four Cecropia species collected in Panama using multivariate data analysis.

Plant species of the genus Cecropia (Urticaceae) are used as traditional medicine in Latin-America, and are commercially available as food supplements. The aim of this study was to characterize and compare the phytochemical constituents of four Cecropia species collected in Panama. The structures of 11 compounds isolated from leaves of C.

Selection of chemical markers for the quality control of medicinal plants of the genus Cecropia.

Context: Several Cecropia (Cecropiaceae) species are traditionally used in Latin America for the treatment of a variety of diseases including diabetes, arterial hypertension, asthma, bronchitis, anxiety, and inflammation. At present, a number of commercial products based on these plants have been introduced into the market with very little information on methods for guaranteeing their quality and safety.

Objective: This work proposes potential chemical markers for the quality control of the raw materials of Cecropia obtusifolia Bertol.

New Curcumin-Loaded Chitosan Nanocapsules: In Vivo Evaluation.

The medicinal applications of curcumin, the major component of , are limited by its poor solubility and low oral bioavailability. In order to overcome this limitation, a method to produce nanocapsules of chitosan loaded with curcumin was developed. Three different molecular weight and deacetylation degree chitosan polymers were used in the formulation in order to prepare curcumin-loaded nanocapsules (mass ratio 1 : 1.

Phylogenetic Diversity of Sponge-Associated Fungi from the Caribbean and the Pacific of Panama and Their In Vitro Effect on Angiotensin and Endothelin Receptors.

Fungi occupy an important ecological niche in the marine environment, and marine fungi possess an immense biotechnological potential. This study documents the fungal diversity associated with 39 species of sponges and determines their potential to produce secondary metabolites capable of interacting with mammalian G-protein-coupled receptors involved in blood pressure regulation. Total genomic DNA was extracted from 563 representative fungal strains obtained from marine sponges collected by SCUBA from the Caribbean and the Pacific regions of Panama.

Marine and soil derived natural products: a new source of novel cardiovascular protective agents targeting the endothelin system.

Inhibition of the endothelin system is a recognized therapeutic approach for treating complex cardiovascular diseases. The search for natural inhibitors of the endothelin system has focused mainly on land, with recent, emerging data suggesting the underestimated potential of marine microorganisms for producing leads with cardioprotective potential. The present work reviews natural products identified as inhibitors of the endothelin system, their origin, their mechanism of action, and their ecological significance.

Modulation of Calcium Signaling of Angiotensin AT1, Endothelin ETA, and ETB Receptors by Silibinin, Quercetin, Crocin, Diallyl Sulfides, and Ginsenoside Rb1.

Angiotensin II and endothelin-1 are potent vasoconstrictive peptides that play a central role in blood pressure regulation. Both peptides exert their pleiotropic effects via binding to their respective G-protein-coupled receptors, i.e.

Critical evaluation of biodegradable polymers used in nanodrugs.

Use of biodegradable polymers for biomedical applications has increased in recent decades due to their biocompatibility, biodegradability, flexibility, and minimal side effects. Applications of these materials include creation of skin, blood vessels, cartilage scaffolds, and nanosystems for drug delivery. These biodegradable polymeric nanoparticles enhance properties such as bioavailability and stability, and provide controlled release of bioactive compounds.

Fluorescence correlation spectroscopy in drug discovery: study of Alexa532-endothelin 1 binding to the endothelin ETA receptor to describe the pharmacological profile of natural products.

Fluorescence correlation spectroscopy and the newly synthesized Alexa532-ET1 were used to study the dynamics of the endothelin ET(A) receptor-ligand complex alone and under the influence of a semisynthetic selective antagonist and a fungal extract on living A10 cells. Dose-dependent increase of inositol phosphate production was seen for Alexa532-ET1, and its binding was reduced to 8% by the selective endothelin ET(A) antagonist BQ-123, confirming the specific binding of Alexa532-ET1 to the endothelin ET(A) receptor. Two different lateral mobilities of the receptor-ligand complexes within the cell membrane were found allowing the discrimination of different states for this complex.

A quarter century of pharmacognostic research on Panamanian flora: a review.

Panama is a unique terrestrial bridge of extreme biological importance. It is one of the "hot spots" and occupies the fourth place among the 25 most plant-rich countries in the world, with 13.4 % endemic species.

5-OHKF and NorKA, depsipeptides from a Hawaiian collection of Bryopsis pennata: binding properties for NorKA to the human neuropeptide Y Y1 receptor.

Two new cyclic depsipeptides, 5-OHKF (1) and norKA (2), together with the known congeners kahalalide F (3) and isokahalalide F ((4S)- methylhexanoic kahalalide F) (4) were isolated from the green alga Bryopsis pennata. The structures of the new compounds were established on the basis of extensive 1D and 2D NMR spectroscopic analysis and mass spectrometric (ESIMS) data. The absolute configuration of each amino acid of 5-OHKF (1) and norKA (2) was determined by chemical degradation and Marfey's analysis.

In vitro effect of sanguinarine alkaloid on binding of [3H]candesartan to the human angiotensin AT1 receptor.

The type of interaction of 5-methyl-2,3,7,8-bis(methylenedioxy)benzo[c]phenanthridinium (sanguinarine), an alkaloid isolated from the root of Bocconia frutescens L., with the human angiotensin AT(1) receptor was evaluated in both intact cells and membrane binding of [3H](2-ethoxy-1-[(2'-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl]-1H-benzimidazoline-7-carboxylic acid) ([3H]candesartan). The results indicate that the inhibition of [3H]candesartan binding by sanguinarine is independent of cell viability, since the alkaloid inhibited at a similar extent radioligand binding on both intact Chinese hamster ovary (CHO) cells transfected with the human angiotensin AT(1) receptor (hAT(1)) and their cell membranes (K(i)=0.

In vitro inhibition of [3H]-angiotensin II binding on the human AT1 receptor by proanthocyanidins from Guazuma ulmifolia bark.

A bioassay-guided fractionation of the 70% acetone extract of the bark of Guazuma ulmifolia Lam. on the inhibition of angiotensin II binding to the AT 1 receptor led to the isolation and identification of bioactive oligomeric and polymeric proanthocyanidins consisting mainly of (-)-epicatechin units. The displacement of [3H]-angiotensin II binding was dose-dependent and correlated with the degree of polymerization of the different fractions containing proanthocyanidins.

Inhibitory activity on binding of specific ligands to the human angiotensin II AT(1) and endothelin 1 ET(A) receptors: bioactive benzo[c]phenanthridine alkaloids from the root of Bocconia frutescens.

A bioassay-guided fractionation of the 80 % ethanolic extract from Bocconia frutescens L. roots, showing a dose-dependent inhibitory effect towards both [(3)H]-angiotensin II and [(3)H]-BQ-123 binding to the human angiotensin II AT 1 and endothelin 1 ET(A) receptors, led to an alkaloidal subfraction as the only responsible fraction for the activity of the whole extract. Among the alkaloids present in this fraction sanguinarine and chelerythrine were significant inhibitors of [(3)H]-angiotensin II binding (hAT 1 receptor), with IC(50) values within the micromolar range.