Herbal Medicine

Herbal medicine has gained cumulative popularity in today’s medical practice. These treatments are the synthesis of therapeutic experiences of generations of traditional physicians for over hundreds of years. However, most of these applications are unorthodox, with over 80% of the world’s population depending on some form of traditional medicine. The increase in the use of herbal products is due to their cultural acceptability, availability, affordability, efficacy and safety claims. This upsurge has led to the improvements in the quality and analysis of herbal products to be made with clinical research advancements in their safety and efficacy. The World Health Organization has recognized the importance of herbal medicine to the health of many people. Therefore, developing guidelines to evaluate herbal medicine by using modern control procedures and applying suitable standards. The current review aims to describe the present state and the projected future of herbal medicine

Olea europaea subsp. africana (Oleaceae)

Background: Medicinal plants have been used as a key source for medication and they remain to provide new therapeutic remedies to date. Extracts of Olea europaea subsp. africana Oleaceae (leaf, bark and root) are used extensively in Africa to treat various diseases traditionally. Phytochemistry has identified phenols, terpenoids and coumarins in different parts of the plant. However, little pharmacological studies have been done on Olea europaea subsp. africana. The present review aims to compile available information on the ethnobotany, phytochemistry, pharmacology and toxicology of Olea africana

Therapeutic efficacy of β-sitosterol treatment on Trypanosoma congolense infection, anemia development, and trans-sialidase (TconTS1) gene expression

BackgroundAfrican animal trypanosomiasis hinders sustainable livestock productivity in sub-Saharan Africa. About 17 million infected cattle are treated with trypanocides annually but most of the drugs are associated with drawbacks, necessitating the search for a promising chemotherapeutic agent.ObjectivesIn this study, the effects of β-sitosterol on Trypanosoma congolense infection were investigated along with its effect on the trans-sialidase gene expressions.ResultsOral treatment with β-sitosterol at 15 and 30 mg/kg body weight (BW) for 14 days significantly (p < 0.05) reduced parasitemia and ameliorated the parasite-induced anemia. Also, the parasite-induced increase in serum urea level and renal histopathological damage scores in addition to renal hypertrophy was significantly (p < 0.05) reverted following treatment with 30 mg/kg BW β-sitosterol. The compound also significantly (p < 0.05) down-regulated the expression of TconTS1 but not TconTS2, TconTS3, and TconTS4. Correlation analysis between free serum sialic acid with the TconTS1 and TconTS2 gene variants revealed negative correlations in the β-sitosterol-treated groups although they were non-significant (p > 0.05) in the group treated with 15 mg/kg BW β-sitosterol. Similarly, a non-significant negative (p > 0.05) correlation between the biomolecule and the TconTS3 and TconTS4 gene variants was observed in the β-sitosterol-treated groups while positive correlations were observed in the infected untreated control group.ConclusionThe observed effect of β-sitosterol on T. congolense infection could make the compound a possible template for the design of novel trypanocides

Anti-Plasmodial Activity of Some Zulu Medicinal Plants and of Some Triterpenes Isolated from Them

Mimusops caffra E. Mey. ex A.DC and Mimusops obtusifolia Lam (both members of the Sapotaceae family), and Hypoxis colchicifolia Bak (family Hypoxidaceae) are used by traditional healers in Zululand to manage malaria. Anti-plasmodial investigation of the crude extracts and some triterpenes isolated from the plants showed activity against a chloroquine sensitive (CQS) strain of Plasmodium falciparum (D10). Among the crude extracts the leaves of M. caffra exhibited the highest activity, with an IC50 of 2.14 μg/mL. The pentacyclic tritepenoid ursolic acid (1), isolated from the leaves of M. caffra was the most active compound (IC50 6.8 μg/mL) as compared to taraxerol (2) and sawamilletin (3) isolated from the stem bark of M. obtusifolia (IC50 > 100). Chemical modification of the ursolic acid (1) to 3β-acetylursolic acid (4) greatly enhanced its anti-plasmodial activity. Compound 4 reduced parasitaemia against Plasmodium berghei by 94.01% in in vivo studies in mice. The cytotoxicity of 3β-acetylursolic acid (IC50) to two human cell lines (HEK293 and HepG2) was 366.00 μg/mL and 566.09 μg/mL, respectively. The results validate the use of these plants in folk medicine

Isolation, characterization, and biological evaluation of a potent anti-malarial drimane sesquiterpene from Warburgia salutaris stem bark

Abstract Background Malaria continues to be a global burden as the efficacy of most commercial anti-malarial drugs has been compromised by the evolution of parasite resistance. With the urgent need created for the development of alternative and more efficient anti-malarial drugs, this study focused on the evaluation of anti-malarial agents of the Warburgia salutaris stem bark. Methods The stem bark was extracted with dichloromethane followed by silica gel column chromatography that led to the isolation of iso-mukaadial acetate, a drimanoid sesquiterpene. This compound was characterized by spectroscopic analysis (1H NMR, 13C NMR, IR and MS), and its structure was confirmed by X-ray crystallography. In vitro anti-plasmodial activity was investigated using a chloroquine sensitive NF54 Plasmodium falciparum strain. Cytotoxicity was measured using the MTT assay on HEK239 and HEPG2 cell lines. Chloroquine-sensitive Plasmodium berghei was used to infect Sprague–Dawley rats for in vivo studies. The W. salutaris crude extract and iso-mukaadial acetate were administered orally at 0.5; 1.5, 2.5 and 5 mg/kg, chloroquine was used as the reference drug. Determination of percentage parasitaemia, haematological parameters, and rat body weights was done throughout the experimental study period. Results The crude extract and iso-mukaadial acetate showed very good activity on the inhibition of parasite growth (IC50 0.01 ± 0.30 µg/ml) and (IC50 0.44 ± 0.10 µg/ml), respectively, with iso-mukaadial acetate having cytotoxicity activity of 36.7 ± 0.8 and 119.2 ± 8.8 (µg/ml) on HEK293 and HEPG2 cells, respectively. The crude extract and iso-mukaadial acetate reduced percentage parasitaemia in a dose-dependent manner in comparison to the control. There were no significant differences in the haematological parameters in all the experimental groups in comparison to control group. This study proves that W. salutaris contains components (including iso-mukaadial acetate) that exhibit anti-malarial activity. This study scientifically validates the use of this plant in folk medicine. Conclusions This study proves that Warburgia salutaris contains components (including iso-mukaadial acetate) that exhibit anti-malarial activity and scientifically validates the use of this plant in folk medicine

Iso-Mukaadial Acetate from Warburgia salutaris Enhances Glucose Uptake in the L6 Rat Myoblast Cell Line

Diabetes mellitus (DM) is a chronic metabolic disorder which has become a major risk to the health of humankind, as its global prevalence is increasing rapidly. Currently available treatment options in modern medicine have several adverse effects. Thus, there is an urgent need to develop alternative cost-effective, safe, and active treatments for diabetes. In this regard, medicinal plants provide the best option for new therapeutic remedies desired to be effective and safe. Recently, we focused our attention on drimane sesquiterpenes as potential sources of antimalarial and antidiabetic agents. In this study, iso-mukaadial acetate (Iso) (1), a drimane-type sesquiterpenoid from the ground stem bark of Warburgia salutaris, was investigated for glucose uptake enhancement in the L6 rat myoblast cell line. In vitro assays with L6 skeletal muscle cells were used to test for cytotoxicity, glucose utilisation, and western blot analysis. Additionally, the inhibition of carbohydrate digestive enzymes and 1,1-diphenyl-2- picrylhydrazyl (DPPH) scavenging activity were analysed in vitro. The cell viability effect of iso-mukaadial acetate was the highest at 3 µg/mL with a percentage of 98.4. Iso-mukaadial acetate also significantly and dose-dependently increased glucose utilisation up to 215.18% (12.5 µg/mL). The increase in glucose utilisation was accompanied by enhanced 5’ adenosine monophosphate-activated protein kinase (AMPK)and protein kinase B (AKT) in dose-dependent manner. Furthermore, iso-mukaadial acetate dose-dependently inhibited the enzymes α-amylase and α-glucosidase. Scavenging activity against DPPH was displayed by iso-mukaadial acetate in a concentration-dependent manner. The findings indicate the apparent therapeutic efficacy of iso-mukaadial acetate isolated from W. salutaris as a potential new antidiabetic agent

Characterization and Biological Evaluation of Zinc Oxide Nanoparticles Synthesized from Pleurotus ostreatus Mushroom

This study aimed to biosynthesize zinc oxide nanoparticles (ZnO NPs) using Pleurotus ostreatus to achieve a simple ecofriendly method, and further evaluate antimicrobial activity and cytotoxicity towards HepG2 and Hek293 cells. The nanoparticles were characterized through UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission and scanning electron microscopy (TEM and SEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), and dynamic light scattering (DLS). The minimal inhibitory concentration (MIC) for antimicrobial activity and MTT assay for cytotoxicity were conducted in vitro. The study revealed an efficient, simple, and ecofriendly method for synthesis of ZnO NPs that have antimicrobial activity. UV-Vis showed peaks at 340 and 400 nm, and the bioactive compounds found in the mushroom acted as capping, reducing, and stabilizing agents. TEM characterized NPs as an amorphous nanosheet, with preferential orientation as projected by SAED patterns. The spherical and agglomerated morphology was observed on SEM, with EDX proving the presence of Zn and O, while XRD indicated a crystallite size of 7.50 nm and a stable nature (zeta potential of −23.3 mV). High cytotoxicity on Hek293 and HepG2 cells was noted for ZnO NPs. The study provides an alternative, ecofriendly method for biosynthesis of ZnO NPs that have antibacterial activity and potential use in cancer treatment

Phloroglucinol as a Potential Candidate against Trypanosoma congolense Infection: Insights from In Vivo, In Vitro, Molecular Docking and Molecular Dynamic Simulation Analyses

Sub-Saharan Africa is profoundly challenged with African Animal Trypanosomiasis and the available trypanocides are faced with drawbacks, necessitating the search for novel agents. Herein, the chemotherapeutic potential of phloroglucinol on T. congolense infection and its inhibitory effects on the partially purified T. congolense sialidase and phospholipase A2 (PLA2) were investigated. Treatment with phloroglucinol for 14 days significantly (p < 0.05) suppressed T. congolense proliferation, increased animal survival and ameliorated anemia induced by the parasite. Using biochemical and histopathological analyses, phloroglucinol was found to prevent renal damages and splenomegaly, besides its protection against T. congolense-associated increase in free serum sialic acids in infected animals. Moreover, the compound inhibited bloodstream T. congolense sialidase via mixed inhibition pattern with inhibition binding constant (Ki) of 0.181 µM, but a very low uncompetitive inhibitory effects against PLA2 (Ki > 9000 µM) was recorded. Molecular docking studies revealed binding energies of −4.9 and −5.3 kcal/mol between phloroglucinol with modeled sialidase and PLA2 respectively, while a 50 ns molecular dynamics simulation using GROMACS revealed the sialidase-phloroglucinol complex to be more compact and stable with higher free binding energy (−67.84 ± 0.50 kJ/mol) than PLA2-phloroglucinol complex (−77.17 ± 0.52 kJ/mol), based on MM-PBSA analysis. The sialidase-phloroglucinol complex had a single hydrogen bond interaction with Ser453 while none was observed for the PLA2-phloroglucinol complex. In conclusion, phloroglucinol showed moderate trypanostatic activity with great potential in ameliorating some of the parasite-induced pathologies and its anti-anemic effects might be linked to inhibition of sialidase rather than PLA2