Phytochemistry, Antioxidant, and Hepatoprotective Potential of Acanthospermum hispidum DC Extracts against Diethylnitrosamine-Induced Hepatotoxicity in Rats

In Vitro Mechanism of Action of Acanthospermum hispidum in Trypanosoma brucei

African trypanosomiasis is a major neglected tropical disease with significant health and economic concerns in sub-Saharan Africa. In the absence of vaccines for African trypanosomiasis, there is a consideration for alternative sources of chemotherapy. Acanthospermum hispidum DC (A. hispidum) is a herbal species of the Asteraceae family that is endowed with rich phytochemicals with unknown mechanisms of antitrypanosomal effects. This study aimed to investigate the cellular mechanisms of antitrypanosomal and antioxidant activities of A. hispidum against Trypanosoma brucei (T. brucei), a causative protozoan species of African trypanosomiasis. Fractions were prepared from the whole plant of A. hispidum through solvent partitioning by employing solvents of varying polarities (hexane, HEX; dichloromethane, DCM; ethyl acetate, EA; aqueous, AQ). The in vitro efficacies and mechanisms of antitrypanosomal activities of A. hispidum were investigated using a panel of cell biological approaches. GC-MS analysis was used to identify the major compounds with a possible contribution to the trypanocidal effects of A. hispidum. A. hispidum fractions displayed significant antitrypanosomal activities in terms of half-maximal effective concentrations (EC₅₀) and selectivity indices (SI) (AH-HEX, EC₅₀ = 2.4 μg/mL, SI = 35.1; AH-DCM, EC₅₀ = 2.2 μg/mL, SI = 38.3; AH-EA, EC₅₀ = 1.0 μg/mL, SI = 92.8; AH-AQ, EC₅₀ = 2.0 μg/mL, SI = 43.8). Fluorescence microscopic analysis showed that at their EC₅₀ values, the fractions of A. hispidum altered the cell morphology as well as the organization of the mitochondria, nucleus, and kinetoplast in T. brucei. At their maximum tested concentrations, the prepared fractions exhibited antioxidant absorbance intensities comparable to the reference antioxidant, Trolox, in contrast to the oxidant intensity of an animal antitrypanosomal drug, diminazene (Trolox, 0.11 A; diminazene, 0.65 A; AH-HEX, 0.20 A, AH-DCM, 0.20 A, AH-EA, 0.13 A, AH-AQ, 0.22 A). GC-MS analysis of the various fractions identified major compounds assignable to the group of alkaloids and esters or amides of aliphatic acids. The results provide useful pharmacological insights into the chemotherapeutic potential of A. hispidum toward drug discovery for African trypanosomiasis.

Taste and chemical composition as drives for utilitarian redundancy and equivalence: a case study in local medical systems in Northeastern Brazil

BACKGROUND

We aimed to verify whether the taste and chemical composition influence the selection of plants in each medicinal category, whether within a socio-ecological system or between different socio-ecological systems. To this end, we use the theoretical bases of the Utilitarian Redundancy Model and the Utilitarian Equivalence Model. We studied the local medical systems of four rural communities in northeastern Brazil, used as models to test our assumptions.

METHODS

The data on medicinal plants and local therapeutic function were obtained from semi-structured interviews associated with the free-listing method, allowing to generate indexes of similarity of therapeutic use between the plants cited in each region. During the interviews, each informer was also asked to report the tastes of the plants cited. Subsequently, we classified each plant in each region according to the most cited taste. The data about the chemical composition of each plant were obtained from a systematic review, using Web of Knowledge and Scopus databases.

RESULTS

Pairs of plants with similar tastes are 1.46 times more likely to have the same therapeutic function within a local medical system (redundancy), but not between medical systems (equivalence). We also find that chemical compounds are not primarily responsible for utilitarian redundancy and equivalence. However, there was a tendency for alkaloids to be doubly present with greater expressiveness in pairs of equivalent plants.

CONCLUSIONS

The results indicate that each social group can create its means of using the organoleptic characteristics as clues to select new species as medicinal. Furthermore, this study corroborates the main prediction of the Utilitarian Equivalence Model, that people in different environments choose plants with traits in common for the same functions.

Acanthospermum hispidum DC: An Updated Review on Phytochemistry and Biological Activities

BACKGROUND

Acanthospermum hispidum DC is a medicinal plant present in America, Africa, Australia, India, Hawaii, and Brazil. In Brazil, the species is used in the treatment of gastrointestinal, respiratory disorders and has expectorant action. In the literature there are studies on the chemical composition of the species, with reports of the presence of alkaloids, flavonoids, hydrolyzable tannins, terpenes, and steroids. In addition, several studies have reported in vitro and in vivo studies that prove the biological properties of extracts and compounds isolated from different organs of the A. hispidum plant, including: hepatoprotectors, antioxidants, antimicrobials and antiparasitic.

OBJECTIVE

The objective of this review is to update the knowledge about the phytochemical, pharmacological and toxicity aspects of A. hispidum, to contribute to the recognition of the species and direct new studies.

METHODS

An extensive bibliographic search was conducted in different scientific databases.

RESULTS

The presence of different chemical constituents in A. hispidum have been identified, among them flavonoids, tannins, terpenes, and steroids. Additionally, antimicrobial and antiparasitic activities were mainly attributed to the species, and other activities not previously described were presented, such as anticholinesterase, antioxidant, hepatoprotective, and hypoglycemic, all based on results of in vitro and in vivo studies. Finally, no reports of toxic effects were found in the in vitro and in vivo tests. After analyzing the articles, it was evidenced that other experiments, with different models using animals, are essential to evaluate the possible mechanisms of action of the extracts and compounds isolated of A. hispidum.

CONCLUSION

Therefore, this review may contribute to the recognition of the importance of A. hispidum and its potential as a medicinal plant and may also guide the conduct of future research regarding the constituents, biological activities, and toxicity of the species.

Characterization and Evaluation of Antioxidant Activity of Aloe schelpei Reynolds

Background

The role of free radical reactions in disease pathology is well known to be involved in many acute and chronic disorders in human beings, such as diabetes, atherosclerosis, aging, immunosuppression and neurodegeneration. The search for new drugs of plant origin becomes increasingly urgent due to drug resistance. Aloe schelpei is an endemic Aloe species traditionally used for the treatment of infectious and chronic diseases.

Aim

This study was conducted to evaluate free radical scavenging activities of leaf latex of Aloe schelpei and its isolated compounds.

Methods

The leaf latex of A. schelpei was subjected to preparative thin-layer chromatography to afford three compounds. Free radical scavenging activities of the leaf latex and its constituents was carried out using a 2, 2-diphenyl-1-picrylhydrazyl method.

Results

Phytochemical investigation of the leaf latex Aloe schelpei by prepartive thin layer chromatography led to the isolation of three compounds, identified as microdontin A/B (1), aloin A/B (2) and aloinoside A/B (3). The results showed that the leaf latex had a strong free radical scavenging activity reaching a maximum of 84.3% at a concentration of 100 μg/mL, and with an IC₅₀ value of 25.3 ± 2.45 μg/mL (p < 0.05). Among the isolated compounds, microdontin A/B (1) was found to have the strongest free radical scavenging activity with an IC₅₀ value of 0.07 ± 0.005 mμ, followed by aloinoside A/B (IC₅₀ = 0.13 ± 0.01 mM) and aloin A/B (IC₅₀ = 0.15 ± 0.02 mM).

Conclusion

The traditional medicinal practice of the leaf latex may be due to the antioxidant activities of the leaf latex of A. schelpei and the isolated compounds.