Bark anatomy, chemical composition and ethanol-water extract composition of Anadenanthera peregrina and Anadenanthera colubrina

Anti-inflammatory effect of Anadenanthera colubrina var. cebil (Griseb.) Altschul in experimental elastase-induced pulmonary emphysema in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal plants have shown promise in the search for new treatments of pulmonary emphysema. Anadenanthera colubrina, a species native to the Caatinga biome in northeastern Brazil, is widely recognized and traditionally employed in the treatment of pulmonary diseases. Many studies corroborate popular knowledge about the medicinal applications of A. colubrina, which has demonstrated a remarkable variety of pharmacological properties, however, its anti-inflammatory and antioxidant properties are highlighted.

AIM OF THE STUDY

The objective of this study was to investigate the anti-inflammatory potential of the crude hydroethanolic extract of A. colubrina var. cebil (Griseb.) Altschul on pulmonary emphysema in rats as well as to determine its potential genotoxic and cytotoxic effects using the micronucleus assay.

MATERIALS AND METHODS

The stem bark of the plant was collected in Pimenteiras-PI and sample was extracted by maceration using 70% ethanol. A portion of the extract underwent phytochemical analyses using TLC and HPLC. In this study, 8-week-old, male Wistar rats weighing approximately ±200 g was utilized following approval by local ethics committee for animal experimentation (No. 718/2022). Pulmonary emphysema was induced through orotracheal instillation of elastase, and treatment with A. colubrina extract or dexamethasone (positive control) concomitantly during induction. Twenty-eight days after the initiation of the protocol, plasma was used for cytokine measurement. Bronchoalveolar lavage (BAL) was used for leukocyte count. After euthanasia, lung samples were processed for histological analysis and quantification of oxidative stress markers. The micronucleus test was performed by evaluating the number of polychromatic erythrocytes (PCE) with micronuclei (MNPCE) to verify potential genotoxic effects of A. colubrina. A differential count of PCE and normochromatic erythrocytes (NCE) was performed to verify the potential cytotoxicity of the extract. Parametric data were subjected to normality analysis and subsequently to analysis of variance and Tukey or Dunnett post-test, non-parametric data were treated using the Kruskal-Wallis test with Dunn's post-test for unpaired samples. P value < 0.05 were considered significant.

RESULTS

The A. colubrina extract did not show a significant increase in the number of MNPCE (p > 0.05), demonstrating low genotoxicity. No changes were observed in the PCE/NCE ratio of treated animals, compared with the vehicle, suggesting low cytotoxic potential of the extract. A significant reduction (p < 0.05) in neutrophilic inflammation was observed in the lungs of rats treated with the extract, evidenced by presence of these cells in both the tissue and BAL. The extract also demonstrated pulmonary antioxidant activity, with a significant decrease (p < 0.05) in myeloperoxidase, malondialdehyde, and nitrite levels. TNFα, IL-1β, and IL-6 levels, as well as alveolar damage, were significantly reduced in animals treated with A. colubrina extract. Phytochemical analyses identified the presence of phenolic compounds and hydrolysable tannins in the A. colubrina extract.

CONCLUSIONS

The findings of this study highlights the safety of the hydroethanolic extract of Anadenanthera colubrina, and demonstrates its potential as a therapeutic approach in the treatment of emphysema. The observed properties of this medicinal plant provide an optimistic outlook in the development of therapies for the treatment of pulmonary emphysema.

Gastroprotective activity and physicochemical analysis of carboxymethylated gum from Anadenanthera colubrina

Biotechnological advancements require the physicochemical alteration of molecules to enhance their biological efficacy for the effective treatment of gastric ulcers. The study aimed to produce a polyelectrolytic compound from red angico gum (AG) by carboxymethylation, evaluate its physicochemical characteristics and investigate gastric protection against ethanol-induced ulcers. AG and carboxymethylated angico gum (CAG) were characterized by Fourier transform infrared spectroscopy, determination of the degree of substitution and gel permeation chromatography (GPC) and 13C NMR techniques. The results demonstrated that the modification of the polymer was satisfactory, presenting conformational changes e improving the interaction with the gastric mucosa. AG and CAG reduced macroscopic and microscopic damage such as edema, hemorrhage and cell loss caused by exposure of the mucosa to alcohol. Both demonstrated antioxidant activity in vitro, and in vivo, pretreatment with gums led to the restoration of superoxide dismutase and glutathione levels compared to the injured group. Concurrently, the levels of malondialdehyde and nitrite decreased. Atomic force microscopy showed that CAG presented better conformational properties of affinity and protection with the gastric mucosa compared to AG in the acidic pH. Based on our findings, it is suggested that this compound holds promise as a prospective product for future biotechnological applications.

Anadenanthera colubrina (Vell) Brenan: Ethnobotanical, phytochemical, pharmacological and toxicological aspects

ETHNOPHARMACOLOGICAL RELEVANCE

Anadenanthera colubrina (Vell.) Brenan is an endemic tree to South America and different parts of it are used by the population for the treatment of various diseases, as well as in indigenous rituals. This species has high pharmacological potential but may present toxic potential due to the presence of psychotropic compounds.

AIM OF THE STUDY

To review published studies with the species A. colubrina regarding ethnobotanical, phytochemical, pharmacological and toxicological aspects, as well as discuss perspectives for new research and protection of this species.

MATERIALS AND METHODS

A literature review was performed by accessing published articles on databases such as: PubMed, Science Direct, Scielo, Scopus, Taylor and Francis online, Springer Link, National Center for Biotechnology Information (NCBI), ACS Publications, Chemspider and Google Scholar. The keywords used were: "Anadenanthera colubrina" or "Mimosa colubrina" or "Piptadenia colubrina" or "Piptadenia macrocarpa" or "Piptadenia grata" or "Anadenanthera macrocarpa" and "medicinal plants" or "pharmacological" or "phytochemicals" or "traditional use" or "toxicological" or "ethnobotanical" or "pre-clinical trial" or "clinical". Articles found by database searches and search engines were screened at four stages: (i) title screening, (ii) locality screening, (iii) abstract screening, and (iv) full text. Other articles found through supplementary searches were screened in the full text whenever available. Each article was assessed by three reviewers at the title and abstract screening stages, except for those found in Portuguese databases that were assessed by the native reviewer.

RESULTS

This robust tree has been popularly useful for agroeconomic, medicinal and as a hallucinogen in religious rituals. According to the published studies, the main parts of the plant are the bark and seeds that are mostly used for respiratory conditions and as entheogens, respectively. It is a rich traditional herbal medicine with many pharmacological properties such as anti-inflammatory, antinociceptive, antidiarrheal, wound healing, antimicrobial, antitumoral, antioxidant, antiaddictive, insecticide and allelopathic that were described in in vitro and in vivo assays, and approximately 56 compounds were identified, suggesting a therapeutic potential for this species. Although most relate to medicinal uses, these are preliminaries and do not show the mechanism of action. The phytochemical assays showed the presence of phenolic compounds, flavonoids, triterpenes, steroids and alkaloids. Some of the compounds are anadanthoflavone, which is exclusive to this species, and no pharmacological or toxicological studies have yet demonstrated this compound. Another important compound is bufotenine which was isolated from seeds and is related to hallucinogenic and antiviral activity. The extracts made from leaves, bark, gum, and fruits appear to be safe, according to both in vivo and in vitro toxicology testing, which all shown low toxicity. Due to the presence of bufotenine in the seeds, it can be toxic, however, it was not found in toxicological assays with the seed extracts.

CONCLUSIONS

Therefore, part of the studies confirms the popular use of A. colubrina, however, more assays with isolated compounds and with the different extracts are necessary to corroborate other uses and the mechanism of action of their pharmacological effects needs to discuss in more detail. Therefore, the present review would be identified the gaps and suggests further studies oriented to validate the popular use. Thus, it must be noted that the use of this species must be controlled in order to minimize the environmental impact, as most of the pharmacological potential was shown with the bark and seeds. Due to its wide use in folk medicine, it is part of the Brazilian medicinal species with priority for conservation.

Anandenanthera colubrina (Vell.) Brenan as an inhibitor of HIV-1 BaL infection

We reported the in vitro anti-HIV-1 activity, cytotoxicity, cytokines expression and chemical profile of Anadenanthera colubrina. Cytotoxicity was evaluated on TZM-bl, HL2/3 cells and macrophages. Anti-HIV-1 activity was determined by Luciferase assay (TZM-bl cells) and by HIV-p24 quantification (macrophages) assessed by ELISA. TZM-bl and HL2/3 cells were used to determine cell-cell fusion inhibition. Cytokines expression was assessed by ELISA. Chemical composition was determined by Gas Chromatography Coupled to Mass Spectrometry. At 66.6 µg/mL, the extract maintained the cell viability above 90%. At 33.28 µg/mL, the extract reduced 82.8% of HIV-1 infection (TZM-bl cells) and HIV-p24 expression (macrophages). The extract inhibited approximately 70% of TZM-bl and HL2/3 cells fusion. Extract did't induce inflammatory response. Phytochemical analysis showed presence of flavonoid, phenolic acids, fatty acids and sugars. This is the first study presenting the anti-HIV effect of A. colubrina, showing low cytotoxicity and no inflammatory stimuli, important requirements for a microbicide development.

Yeast-Host Interactions: Anadenanthera colubrina Modulates Virulence Factors of C. albicans and Inflammatory Response In Vitro

Oral candidiasis is one of the most common fungal infections in humans. Its incidence has increased widely, as well as the antifungal resistance, demanding for the search for novel antifungal therapeutic agents. Anadenanthera colubrina (Vell.) Brenan is a plant species that has been proven to possess pharmacological effects, including antifungal and anti-inflammatory activities. This study evaluated in vitro the effects of standardized A. colubrina extract on virulence factors of Candida albicans and its regulation on immune response through C. albicans-host interaction. Antifungal activity was evaluated by Broth Microdilution Method against reference Candida strains (C. albicans, C. glabrata, C. tropicalis; C. dubliniensis). Anti-biofilm effect was performed on C. albicans mature biofilm and quantified by CFU/mL/g of biofilm dry weight. Proleotlytic enzymatic activities of proteinase and phospholipase were assessed by Azocasein and Phosphatidylcholine assays, respectively. Cytotoxicity effect was determined by Cell Titer Blue Viability Assay on Human Gingival Fibroblasts. Co-cultured model was used to analyze C. albicans coexisting with HGF by Scanning Electron Microscopy and fluorescence microscopies; gene expression was assessed by RT-PCR of C. albicans enzymes (SAP-1, PLB-1) and of host inflammatory cytokines (IL-6, IL-8, IL-1β, IL-10). Cytokines secretion was analysed by Luminex. The extract presented antifungal effect with MIC<15.62 μg/ml against Candida strains. Biofilm and proteolytic activity were significant reduced at 312.4 μg/ml (20 × 15.62 μg/ml) extract concentration. Cell viability was maintained higher than 70% in concentrations up to 250 μg/ml (LD50 = 423.3 μg/ml). Co-culture microscopies demonstrated a substantial decreased in C. albicans growth and minimal toxicity against host cells. Gene expressions of SAP-1/PLB-1 were significantly down-regulated and host immune response was modulated by a significant decreased on IL-6 and IL-8 cytokines secretion. A. colubrina had antifungal activity on Candida strains, antibiofilm, and anti-proteolytic enzyme effects against C. albicans. Presented low cytotoxicity to the host cells and modulatory effects on the host immune response.

Evaluation of the Phytotoxicity of Urochloa humidicola Roots by Bioassays and Microscopic Analysis. Characterization of New Compounds

Herbicides are a key element in agriculture but they do cause environmental problems and natural alternatives are being sought. In this context, invasive plants could provide an as yet unexplored source for the development of future herbicides. Urochloa humidicola has great invasive potential in Brazilian environments as it hampers the establishment of other plants. The phytotoxicity of U. humidicola root extracts has been evaluated, and the major components have been identified. The phytotoxicity of the extract was assessed in the wheat coleoptile assay on seeds of troublesome weeds and on Anadenanthera colubrina, a tree species used in ecological restoration programs. The ethyl acetate extract showed the highest activity, and the most affected weeds were E. crus-galli, M. maximus, and A. viridis with the latter weed more affected by the extract than by the herbicide Logran. Microscopic ultrastructural analysis of A. colubrina roots indicated possible signals of cell death. Seven compounds were identified in the ethyl acetate extract of which one diterpene and four saponins are new. Six of these compounds were tested in the wheat coleoptile bioassay. The most active were diterpene 1 and saponins 2, 3, and 6. The phytotoxic activity of U. humidicola explains the issues observed in ecological restoration with A. colubrina in the presence of Urochloa species, and its effect on weeds reinforces its potential use in agriculture.

Biopolymer Extracted from Anadenanthera colubrina (Red Angico Gum) Exerts Therapeutic Potential in Mice: Antidiarrheal Activity and Safety Assessment

Anadenanthera colubrina var. cebil (Griseb.) Altschul (Fabaceae family), commonly known as the red angico tree, is a medicinal plant found throughout Brazil’s semi-arid area. In this study, a chemical analysis was performed to investigate the antidiarrheal activity and safety profile of red angico gum (RAG), a biopolymer extracted from the trunk exudate of A. colubrina. Upon FT-IR spectroscopy, RAG showed bands in the regions of 1608 cm⁻¹, 1368 cm⁻¹, and 1029 cm⁻¹, which relate to the vibration of O–H water molecules, deformation vibration of C-O bands, and vibration of the polysaccharide C-O band, respectively, all of which are relevant to glycosidic bonds. The peak molar mass of RAG was 1.89 × 10⁵ g/mol, with the zeta potential indicating electronegativity. RAG demonstrated high yield and solubility with a low degree of impurity. Pre-treatment with RAG reduced the total diarrheal stool and enteropooling. RAG also enhanced Na+/K+-ATPase activity and reduced gastrointestinal transit, and thereby inhibited intestinal smooth muscle contractions. Enzyme-Linked Immunosorbent Assay (ELISA) demonstrated that RAG can interact with GM1 receptors and can also reduce E. coli-induced diarrhea in vivo. Moreover, RAG did not induce any signs of toxicity in mice. These results suggest that RAG is a possible candidate for the treatment of diarrheal diseases.

Bioguided Purification of Active Compounds from Leaves of Anadenanthera colubrina var. cebil (Griseb.) Altschul

Anadenanthera colubrina var cebil (Griseb.) Altschul is a medicinal plant found throughout the Brazilian semi-arid area. This work performed a bioguided purification of active substances present in ethyl acetate extract from A. colubrina leaves. The anti-Staphylococcus aureus and antioxidant actions were used as markers of bioactivity. The extract was subjected to flash chromatography resulting in five fractions (F1, F2, F3, F4, and F5). The fractions F2 and F4 presented the highest antimicrobial action, with a dose able to inhibit 50% of bacteria growth (IN50) of 19.53 μg/mL for S. aureus UFPEDA 02; whereas F4 showed higher inhibitory action towards DPPH radical (2,2-diphenyl-1-picryl-hydrazyl-hydrate) [dose able to inhibit 50% of the radical (IC50) = 133 ± 9 μg/mL]. F2 and F4 were then subjected to preparative high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR), resulting in the identification of p-hydroxybenzoic acid and hyperoside as the major compounds in F2 and F4, respectively. Hyperoside and p-hydroxybenzoic acid presented IN50 values of 250 μg/mL and 500 μg/mL against S. aureus UFPEDA 02, respectively. However, the hyperoside had an IN50 of 62.5 μg/mL against S. aureus UFPEDA 705, a clinical isolate with multidrug resistant phenotype. Among the purified compounds, the proanthocyanidins obtained from F2 exhibited the higher antioxidant potentials. Taken together, these results highlight the potential of A. colubrina leaves as an alternative source of biomolecules of interest for the pharmaceutical, food, and cosmetic industries.