Filaricidal activity of Daniellia oliveri and Psorospermum febrifugum extracts

An automated, high-resolution phenotypic assay for adult Brugia malayi and microfilaria

Brugia malayi are thread-like parasitic worms and one of the etiological agents of Lymphatic filariasis (LF). Existing anthelmintic drugs to treat LF are effective in reducing the larval microfilaria (mf) counts in human bloodstream but are less effective on adult parasites. To test potential drug candidates, we report a multi-parameter phenotypic assay based on tracking the motility of adult B. malayi and mf in vitro. For adult B. malayi, motility is characterized by the centroid velocity, path curvature, angular velocity, eccentricity, extent, and Euler Number. These parameters are evaluated in experiments with three anthelmintic drugs. For B. malayi mf, motility is extracted from the evolving body skeleton to yield positional data and bending angles at 74 key point. We achieved high-fidelity tracking of complex worm postures (self-occlusions, omega turns, body bending, and reversals) while providing a visual representation of pose estimates and behavioral attributes in both space and time scales.

A review of indigenous knowledge and ethnopharmacological significance of African Copaiba Balsam Tree, Daniellia oliveri (Fabaceae)

Daniellia oliveri has found its indigenous relevance in the management of diseases including but not limited to diabetes mellitus, tuberculosis, fever, ulcers, pain, worm manifestation, pneumonia, skin ailments, infectious diseases, sickle cell anaemia, hence, a review of its indigenous knowledge, ethnopharmacological and nutritional benefits was undertaken. Information used for the review was sourced from popular scientific databases (Google Scholar, PubMed, Science Direct, Web of Science, BioMed Central, JSTOR, African Plant, Global Biodiversity Information and others), conference proceedings, dissertations or theses, chapters in books, edited books, and journal collections. The materials obtained from 121 scientific documents targeting majorly between 1994 and 2023 established the presence of major secondary metabolites (such as polyphenols, flavonoids, saponins, alkaloids, etc.), minerals (e.g., sodium, potassium, phosphorus, selenium, calcium, magnesium, etc.), vitamins (beta-carotene, thiamine, riboflavin, niacin, ascorbic acid, etc.), and nutrients (crude protein, moisture, dry matter, ether, carbohydrates, and energy). Literature also lent credence to the preliminary safety profiles of the plant and its pharmacological potentials as analgesic, antinociceptive, antioxidant, antidiabetic, antidiarrhoeal, anthelmintic, anti-inflammatory, antimelanogenesis, antimicrobial, antiplasmodial, antisickling, cardiotoxic, cytotoxic, and neuroprotective agents. While the review is majorly limited to Africa particularly western countries (such as Nigeria, Burkina Faso, Mali, Ghana, Togo, and Benin) and the plant is found to be largely underutilized, it is evident that limited information exists on the in vivo pharmacological evaluation, bioactive compounds identification, and there is a lack of preclinical and clinical trials for possible drug development. Based on the aforementioned, it is hoped that further research studies geared toward providing insights into the established grey areas (such as traditional use investigation, targeted or assay-guided compounds identification, and preclinical and clinical studies) are necessary in order to fully explore the therapeutic, nutritional, and economic benefits of the plant.

Anti-inflammatory and antinociceptive activities of Daniellia oliveri (Fabaceace) stem bark extract

ETHNOPHARMACOLOGICAL RELEVANCE

Daniellia oliveri (Rolfe) Hutch. & Dalziel (Fabaceae) is used for the treatment of inflammatory diseases and pains (chest pain, toothache and lumbago) and rheumatism.

AIM OF THE STUDY

The study investigates the anti-inflammatory and antinociceptive properties of D. oliveri and possible mechanism of antiinflammatory action.

MATERIALS AND METHODS

Acute toxicity of the extract was evaluated in mice using the limit test. The anti-inflammatory activity was assessed in xylene-induced paw oedema and carrageenan-induced air-pouch models at doses of 50, 100 and 200 mg/kg, p.o. Volume of exudate, total protein, leukocyte counts, myeloperoxidase (MPO) and concentration of cytokines (TNF-α and IL-6) were measured in the exudate of rats in the carrageenan-induced air-pouch model. Other parameters include lipid peroxidation (LPO), nitric oxide (NO) and antioxidant indices (SOD, CAT and GSH). Histopathology of the air pouch tissue was also carried out. The antinociceptive effect was assessed using acetic acid-induced writhing, tail flick and formalin tests. Locomotor activity was done in the open field test. The extract was analysed with HPLC-DAD-UV technique.

RESULTS

The extract showed significant anti-inflammatory effect (73.68 and 75.79%, inhibition) in xylene-induced ear oedema test at the dose of 100 and 200 mg/kg, respectively. In carrageenan air pouch model, the extract significantly reduced exudate volume, protein concentration, the migration of leukocytes and MPO production in the exudate. The concentrations of cytokines TNF-α (12.25 ± 1.80 pg/mL) and IL-6 (21.12 pg/mL) in the exudate at the dose of 200 mg/kg were reduced compared to carrageenan alone group (48.15 ± 4.50 pg/mL; 82.62 pg/mL) respectively. The extract showed significant increase in the activities of CAT and SOD and GSH concentration. The histopathological assessment of the pouch lining revealed reduction of immuno-inflammatory cell influx. Nociception was significantly inhibited by the extract in acetic acid-induced writhing model and the second phase of formalin test indicating a peripheral mechanism of action. The open field test showed that D. oliveri did not alter locomotor activity. The acute toxicity study did not cause mortality or signs of toxicity at 2000 mg/kg, p.o. We identified and quantified caffeic acid, p-coumaric acid, ferulic acid, rutin, apigenin-7-glucoside, quercetin and kaempferol in the extract.

CONCLUSION

The results of our study showed that the stem bark extract of D. oliveri possesses anti-inflammatory and antinociceptive activities thereby supporting its traditional use in the treatment of some inflammatory and painful disorders.

Whole-organism phenotypic screening methods used in early-phase anthelmintic drug discovery

Diseases caused by parasitic helminths (worms) represent a major global health burden in both humans and animals. As vaccines against helminths have yet to achieve a prominent role in worm control, anthelmintics are the primary tool to limit production losses and disease due to helminth infections in both human and veterinary medicine. However, the excessive and often uncontrolled use of these drugs has led to widespread anthelmintic resistance in these worms - particularly of animals - to almost all commercially available anthelmintics, severely compromising control. Thus, there is a major demand for the discovery and development of new classes of anthelmintics. A key component of the discovery process is screening libraries of compounds for anthelmintic activity. Given the need for, and major interest by the pharmaceutical industry in, novel anthelmintics, we considered it both timely and appropriate to re-examine screening methods used for anthelmintic discovery. Thus, we reviewed current literature (1977-2021) on whole-worm phenotypic screening assays developed and used in academic laboratories, with a particular focus on those employed to discover nematocides. This review reveals that at least 50 distinct phenotypic assays with low-, medium- or high-throughput capacity were developed over this period, with more recently developed methods being quantitative, semi-automated and higher throughput. The main features assessed or measured in these assays include worm motility, growth/development, morphological changes, viability/lethality, pharyngeal pumping, egg hatching, larval migration, CO₂- or ATP-production and/or enzyme activity. Recent progress in assay development has led to the routine application of practical, cost-effective, medium- to high-throughput whole-worm screening assays in academic or public-private partnership (PPP) contexts, and major potential for novel high-content, high-throughput platforms in the near future. Complementing this progress are major advances in the molecular data sciences, computational biology and informatics, which are likely to further enable and accelerate anthelmintic drug discovery and development.