Aaron Opoku Antwi

Finished herbal antimalarials are widely used in Ghana, although scientific reports regarding their antiplasmodial activity and safety of these products are limited. This study, therefore, assessed the antiplasmodial activities and safety of three widely distributed antimalarial polyherbal products. These products (samples A, B and C) were obtained through a minisurvey conducted in the Accra and Kumasi Metropolises. The SYBR Green fluorescence antiplasmodial assay was conducted on different stages of chloroquine‐resistant and chloroquine‐sensitive strains of P. falciparum. Cytotoxicity and subacute toxicity were assessed following MTT assay and OECD guidelines, respectively. Samples A, B and C yielded IC ₅₀ (μg/mL) values of 0.869 ± 0.10, 0.828 ± 0.05 and 3.07 ± 0.098, respectively, against the chloroquine‐sensitive (3D7) strain at the trophozoite stage. At the schizont stage, samples A, B and C exhibited moderate to weak activities with IC ₅₀ (μg/mL) values of 9.96 ± 0.63, 7.71 ± 1.63 and 13.66 ± 1.91, respectively. At the gametocyte stage, samples A, B and C displayed moderate to weak activity with IC ₅₀ (μg/mL) values of 13.59 ± 0.49, 17.92 ± 0.814 and 59.65 ± 1.61, respectively. Parasite inhibition against the chloroquine‐resistant strain (Dd2) at the trophozoite stage demonstrated good antiplasmodial activities for samples A and B, with IC ₅₀ (μg/mL) values of 0.939 ± 0.04 and 0.318 ± 0.01, respectively. Sample C yielded an IC ₅₀ (μg/mL) value of 15.09 ± 0.319. In conclusion, the three products are antiplasmodial agents and are safe in the rodent model.

Inflammatory bowel disease (IBD) is a relapsing-remitting gastrointestinal disorder characterized by chronic mucosal inflammation and dysregulated immune responses to gut microorganisms. Despite the many advancements in its management, current treatments are often limited by their adverse effects, high cost, and incomplete remission. Eleusine indica, a medicinal plant used in folkloric medicine, is known for its anti-inflammatory properties. However, its efficacy in IBD remains not known. This study evaluated the potential effect of the hydroethanolic extract of Eleusine indica (EI) in a rat model of trinitrobenzene sulphonic acid (TNBS)-induced colitis. Colitis was induced in Sprague Dawley rats via rectal administration of TNBS. Rats were subsequently treated orally with EI (200, 400, or 600 mg/kg) or sulfasalazine (500 mg/kg) for 7 days. Disease activity index (DAI), colon weight-to-length ratio, macroscopic and histopathological changes, haematological parameters, and serum levels of markers of inflammation: TNF-α, p38 MAPK, and of oxidative stress: glutathione (GSH) were assessed. EI significantly improved the DAI (p < 0.05) and reduced colon weight-to-length ratio (p < 0.05) and macroscopic colonic damage in TNBS-induced rats. Histopathological analysis revealed preserved mucosal architecture and reduced inflammatory infiltration in EI-treated groups. EI also significantly downregulated TNF-α (p < 0.0001) and p38 MAPK (p < 0.0001) while preserving GSH levels (p < 0.05), indicating suppression of inflammation and oxidative stress. Haematological parameters showed reversal of TNBS-induced leucocytosis (p < 0.05). EI demonstrated potent anti-colitic activity comparable to sulfasalazine. The findings from this study support its potential as a herbal therapeutic option for IBD.

Introduction: Aurantio‐obtusin is a trihydroxyanthraquinone found in the seeds of Cassia tora and Cassia obtusifolia . Its neuroprotective, anti‐inflammatory, anti‐allergic, and antioxidant potential has been documented in multiple studies. While previous reports mention its potential as an antiasthma agent, its effects on allergen‐induced airway inflammation have not been explored. Method: Our study reports on the mechanisms by which aurantio‐obtusin exerts its effects on underlying inflammation in experimentally‐induced allergic asthma. The effect of aurantio‐obtusin pretreatment on molecular and histological changes in guinea pig lungs when challenged with aerosolized ovalbumin was assessed. Results: Our results showed that aurantio‐obtusin significantly reduced ovalbumin (OVA)‐induced increase in serum OVA‐specific immunoglobulin E (OVA‐sIgE) and intercellular adhesion molecule (ICAM)‐1. Aurantio‐obtusin further suppressed inflammatory cytokine expression (IL‐8, TNF‐α, IL‐6 and thymic stromal lymphopoietin) as well as malondialdehyde, a product of oxidative stress in bronchial lavage. The histopathological assessment showed a reduced transit of inflammatory cells and reduced deposition of collagen in the lungs of aurantio‐obtusin‐treated guinea pigs. Conclusion: Overall, the data suggests that aurantio‐obtusin mitigated ovalbumin‐induced airway inflammation by impeding the production of OVAsIgE and suppressing levels of key pro‐inflammatory cytokines. Our findings suggest that aurantio‐obtusin has potential benefits in the management of allergic airway inflammation in type 2 asthma.

Airway inflammation in asthma is managed with anti-inflammatory steroids such as dexamethasone (DEX). However, about 20 of asthmatics do not respond to this therapy and are classified as steroid-resistant. Currently, no effective therapy is available for steroid-resistant asthma. This work therefore evaluated the effect of a plant sterol, stigmasterol (STIG), and stigmasterol-dexamethasone combination (STIG+DEX) in LPS-ovalbumin-induced steroid-resistant asthma in Guinea pigs. To do this, the effect of drugs on inflammatory features such as airway hyperreactivity and histopathology of lung tissue was evaluated. Additionally, the possible pathway of drug action was assessed by measuring events such neutrophil levels, oxidative and nitrative stress, and histone deacetylase 2 (HDAC2) and interleukin 17 (IL-17) levels. STIG alone did not affect inflammatory features, although it caused some changes in the molecular events associated with steroid-resistant asthma. However, STIG+DEX caused significant modulation of inflammatory features by protecting against destruction of lung tissue. The modulation of inflammatory features was associated with significant inhibition of neutrophilia and oxidative and nitrative stress, decrease in HDAC2, and increase in IL-17 levels that are usually associated with steroid-resistant asthma. Our findings show that although STIG and DEX individually do not protect against steroid-resistant asthma, their coadministration results in significant modulation of inflammatory features and the associated molecular events that lead to steroid-resistant asthma.

Background: Xylopic acid (XA) is the principal constituent obtained from the biofractionation of the dried fruits of Xylopia aethiopica. Our initial reports have established the acute anti-inflammatory activity of this kaurene diterpene. Objective: Currently, we investigate the chronic anti-inflammatory activity of xylopic acid. Method: The adjuvant-induced arthritis model in rats was employed in carrying out the study. Results: It was observed from the study that XA significantly (P < 0.05) suppressed the oedema associated with adjuvant arthritis while preventing associated joint deformation as identified from the radiographs. Histopathological analysis of joints of treated animals revealed signs of bone reformation and re-calcification following XA administration. From the haematological analysis, xylopic acid significantly decreased eosinophil sedimentation rate (ESR) while also decreasing white blood cells (WBC) which was increased after arthritis induction. Serum analysis showed the inhibitory effect of XA on serum expression of IL-6 and TNF-alpha in arthritic rats. Conclusion: Our study demonstrates the anti-arthritic activity of orally administered XA while pointing to a possible mechanism of its anti-inflammatory action.