Study on South African Indigenous Teas-Antioxidant Potential, Nutritional Content, and Hypoxia-Induced Cyclooxygenase Inhibition on U87 MG Cell Line.

Background: This study comparatively assessed seven indigenous traditional tea plants on several attributes that included antioxidant, nutritional, caffeine contents, and cyclooxygenase activity. Methodology: Nutritional content of all tea plants were determined for energy, fat, carbohydrates, total sugars, dietary fiber and amino acids. Antioxidant potential and the antioxidant potentiating secondary metabolites were also measured and compared. Further, we investigated the tea plants for any role they would have on cyclooxygenase (COX) activity on cobalt chloride (CoCl2) induced human glioma cell lines (U87MG). Results: The tea plants were found non-cytotoxic at concentrations tested against the human Chang liver and HeK 293 kidney cells and were found to be naturally caffeine free. The lowest and highest extraction yield among the tea plants was 7.1% for B. saligna and 15.48% for L. scaberrimma respectively. On average, the flavonol content was 12 to 8 QE/g, ORAC 800 µmol TE/g, TEAC 150 µmol TE/g, FRAP 155 µmol AAE/g, polyphenols 40 mg GAE/g, flavanols 0.35 mg CE/g, flavonols 12 mg QE/g and total flavonoid content (TFC) 180 µg QE/mg. The COX activity has been found to be inhibited by a dose-dependent manner by L. scaberrimma, B. saligna and L. javanica. Conclusion: The results further support competitive value of tea plants and need for improved and further development.

Cannabis sativa L. protects against oxidative injury in kidney (vero) cells by mitigating perturbed metabolic activities linked to chronic kidney diseases.

ETHNOPHARMACOLOGICAL RELEVANCE: Cannabis sativa L. is among numerous medicinal plants widely used in traditional medicine in treating various ailments including kidney diseases. AIMS: The protective effect of C. sativa on oxidative stress, cholinergic and purinergic dysfunctions, and dysregulated glucogenic activities were investigated in oxidative injured kidney (Vero) cell lines. METHODS: Fixed Vero cells were treated with sequential extracts (hexane, dichloromethane [DCM] and ethanol) of C. sativa leaves for 48 h before subjecting to MTT assay. Vero cells were further incubated with FeSO4 for 30 min, following pretreatment with C. sativa extracts for 25 min. Normal control consisted of Vero cells not treated with the extracts and/or FeSO4, while untreated (negative) control consisted of cells treated with only FeSO4. RESULTS: MTT assay revealed the extracts were slightly cytotoxic at the highest concentrations (250 µg/mL). There was a significant depletion in glutathione level and catalase activity on induction of oxidative stress, with significant elevation in malondialdehyde level, acetylcholinesterase, ATPase, ENTPDase, fructose-1,6-biphosphatase, glucose 6-phosphatase and glycogen phosphorylase activities. These activities and levels were significantly reversed following pretreatment with C. sativa extracts. CONCLUSION: These results portray the protective potentials of C. sativa against iron-mediated oxidative renal injury as depicted by the ability of its extracts to mitigate redox imbalance and suppress acetylcholinestererase activity, while concomitantly modulating purinergic and glucogenic enzymes activities in Vero cells.

Root Extract of a Micropropagated Prunus africana Medicinal Plant Induced Apoptosis in Human Prostate Cancer Cells (PC-3) via Caspase-3 Activation.

Prostate cancer is one of the major causes of cancer-related deaths among men globally. Medicinal plants have been explored as alternative treatment options. Herein, we assessed the in vitro cytotoxic effects of 70% ethanolic root extracts of six-month-old micropropagated Prunus africana (PIR) on PC-3 prostate cancer cells as an alternative to the traditionally used P. africana stem-bark extract (PWS) treatment. In vitro assays on PC-3 cells included annexin-V and propidium iodide staining, DAPI staining, and caspase-3 activity analysis through western blotting. PC-3 cells were exposed to PWS and PIR at different concentrations, and dose-dependent antiprostate cancer effects were observed. PC-3 cell viability was determined using CCK-8 assay, which yielded IC50 values of 52.30 and 82.40 µg/mL for PWS and PIR, respectively. Annexin-V and PI staining showed dose-dependent apoptosis of PC-3 cells. Significant (p < 0.001) percent of DAPI-stained apoptotic PC-3 cells were observed in PWS, PIR, and doxorubicin treatment compared with the negative control. PWS treatment substantially elevated cleaved caspase-3 levels in PC-3 cells compared with the PIR treatment. These results provide evidence for the antiprostate cancer potential of PIR and sets a basis for further research to enhance future utilization of roots of young micropropagated P. africana for prostate cancer treatment as an alternative to stem bark. Moreover, micropropagation approach may help provide the required raw materials and hence reduce the demand for P. africana from endangered wild population.

Unravelling the Anticancer Mechanisms of Traditional Herbal Medicines with Metabolomics.

Metabolite profiling of cancer cells presents many opportunities for anticancer drug discovery. The Chinese, Indian, and African flora, in particular, offers a diverse source of anticancer therapeutics as documented in traditional folklores. In-depth scientific information relating to mechanisms of action, quality control, and safety profile will promote their extensive usage in cancer therapy. Metabolomics may be a more holistic strategy to gain valuable insights into the anticancer mechanisms of action of plants but this has remained largely unexplored. This review, therefore, presents the available metabolomics studies on the anticancer effects of herbal medicines commonly used in Africa and Asia. In addition, we present some scientifically understudied 'candidate plants' for cancer metabolomics studies and highlight the relevance of metabolomics in addressing other challenges facing the drug development of anticancer herbs. Finally, we discussed the challenges of using metabolomics to uncover the underlying mechanisms of potential anticancer herbs and the progress made in this regard.

In vitro bioactivity of the fractions and isolated compound from Combretum elaeagnoides leaf extract against selected foodborne pathogens.

ETHNOPHARMACOLOGICAL RELEVANCE: Combretum species are used traditionally for the treatment of diarrhoea, hookworm, fever, inflammation, pain and infectious diseases. Infections are commonly caused by the intake of food contaminated with foodborne pathogens. These are a significant concern in the food industry owing to their ability to form biofilms and cause food spoilage, despite the availability of modern food preservation techniques. Combretum elaeagnoides Klotzsch (Combretaceae) is used in southern African traditional medicine against infections and diarrhoea. AIM OF THE STUDY: This study evaluated the antimicrobial ability of C. elaeagnoides leaf fractions and the isolated compound quercetin-3-O-rhamnoside against a panel of foodborne pathogens, and biofilms formed by them. The samples were also assessed for their antioxidant activity and cytotoxicity. MATERIALS AND METHODS: Fractions prepared from the methanol extract of the leaves, and a bioactive compound (quercetin-3-O-rhamnoside) isolated from the ethyl acetate fraction were investigated for activity against nine reference and clinical strains of foodborne pathogens. The microdilution method was used to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the fractions and compound. The inhibition of biofilm formation and the crystal violet staining assays were used to determine the antibiofilm efficacy. The DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay and the 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) electron reduction assay were used to determine the antioxidant potential of the fractions and compound. The cytotoxicity was assessed using the 3-(4, 5-dimethylthiazolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay against Vero African monkey kidney cells. RESULTS: The fractions were active against all tested organisms, with MIC values ranging from 0.03 to 1.25 mg/mL. The best MBC was 0.63 mg/mL. All the fractions and the purified compound inhibited biofilm formation of Staphylococcus aureus and Salmonella Typhimurium, with percentage inhibition values greater than 50% at 1 mg/mL. The compound had very promising antibiofilm activity against Escherichia coli 1 (ATCC 25922) with percentage inhibition of >150%. The compound and fractions had good radical scavenging potential against the DPPH and ABTS radicals. Quercetin-3-O-rhamnoside and the fractions were relatively non-cytotoxic. CONCLUSION: The ability of the fractions and compound to reduce and inhibit biofilm biomass and their promising antioxidant potential provide motivation to further investigate the use of plants to protect food products from contamination, as well as to treat infections characterized by bacterial biofilms.

Selective cytotoxic and anti-metastatic activity in DU-145 prostate cancer cells induced by Annona muricata L. bark extract and phytochemical, annonacin.

BACKGROUND: Annona muricata L. was identified as a popular medicinal plant in treatment regimens among cancer patients in Jamaica by a previously conducted structured questionnaire. Ethnomedically used plant parts, were examined in this study against human prostate cancer cells for the first time and mechanisms of action elucidated for the most potent of them, along with the active phytochemical, annonacin. METHODS: Nine extracts of varying polarity from the leaves and bark of A. muricata were assessed initially for cytotoxicity using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on PC-3 prostate cancer cells and the ethyl acetate bark (EAB) extract was identified as the most potent. EAB extract was then standardized for annonacin content using High-performance Liquid Chromatography - Mass Spectrometry (HPLC-MS) and shown to be effective against a second prostate cancer cell line (DU-145) also. The mode of cell death in DU-145 cells were assessed via several apoptotic assays including induction of increased reactive oxygen species (ROS) production, reduction of mitochondrial membrane potential, activation of caspases and annexin V externalization combined with morphological observations using confocal microscopy. In addition, the potential to prevent metastasis was examined via inhibition of cell migration, vascular endothelial growth factor (VEGF) and angiogenesis using the chorioallantoic membrane assay (CAM). RESULTS: Annonacin and EAB extract displayed selective and potent cytotoxicity against the DU-145 prostate carcinoma cells with IC50 values of 0.1 ± 0.07 µM and 55.501 ± 0.55 µg/mL respectively, without impacting RWPE-1 normal prostate cells, in stark contrast to chemotherapeutic docetaxel which lacked such selectivity. Docetaxel's impact on the cancerous DU-145 was improved by 50% when used in combination with EAB extract. Insignificant levels of intracellular ROS content, depolarization of mitochondrial membrane, Caspase 3/7 activation, annexin V content, along with stained morphological evaluations, pointed to a non-apoptotic mode of cell death. The extract at 50 µg/mL deterred cell migration in the wound-healing assay, while inhibition of angiogenesis was displayed in the CAM and VEGF inhibition assays for both EAB (100 µg /mL) and annonacin (0.5 µM). CONCLUSIONS: Taken together, the standardized EAB extract and annonacin appear to induce selective and potent cell death via a necrotic pathway in DU-145 cells, while also preventing cell migration and angiogenesis, which warrant further examinations for mechanistic insights and validity in-vivo.

In vitro antibacterial and cytogenotoxicological properties of the aqueous extract of Cymbopogoncitratus Stapf (DC) leaf.

BACKGROUND: Microbial infection of the genital tract or semen is one of the leading causes of male infertility. Consequently, there is a need to seek alternative products from natural sources. OBJECTIVES: The antibacterial, phytochemical and cytogenotoxicological assessments of the aqueous extract of Cymbopogon citratus leaf were evaluated. METHODS: The antibacterial potential of the extract was done via agar-well diffusion and microdilution techniques. The phytochemical analysis was done via standard protocols.The cytogenotoxicity of the extract were analyzed using the Allium cepa assay. RESULTS: All test organisms were found to be sensitive to the extract except Pseudomonas. aeruginosa where no measurable zone of inhibition could be ascertained at all concentrations assessed.The highest mean inhibition diameter of 21.33±1.20mm against S. sapophyticus was recorded and a concentration-dependent susceptibility noticed. The phytochemical results revealed the presence of saponins, flavonoid, glycoside, steroids, terpenoid and alkaloids. The Alliumcepa root showed reduced mitotic indices following aconcentration-dependent increase in the extract.It can be said that the aqueous extract of C. citratus had inhibitory activities against the tested pathogenic organisms with relative anti-tumour potential. CONCLUSION: This study indicated, C. citratus could be a potential source for antibacterial compounds for the possible treatment of male reproductive related infections.

Aphrodisiac potentials of the ethanol extract of Aloe barbadensis Mill. root in male Wistar rats.

BACKGROUND: Aloe barbadensis (AB) is a short stemmed succulent medicinal herb that is being used by locals in Nigeria to enhance libido. Therefore this study evaluates the aphrodisiac potential and acute toxicological effect of A. barbadensis (AB) root in male Wistar rats. METHODS: Aphrodisiac potential was determined following the oral administration of graded doses (100, 200 and 400 mg/kg) of ethanol extract of A. barbadensis root. Sildenafil citrate (Viagra) and distilled water served as positive and negative controls respectively. Sexual behavioural parameters (mounting and intromission frequencies, mounting, intromission and ejaculatory latencies) were observed. Serum testosterone and cholesterol concentrations were also progressively monitored on days 1, 7 and 14. The acute toxicological evaluation of the plant were based on any onset behavioural changes and mortality respectively. RESULTS: The findings from the sexual behavioural study indicated that the ethanol extract of A. barbadensis significantly increased mounting frequency and intromission frequency but significantly decreased mount and intromission latencies in a dose dependent manner particularly on day 1 and 14. The ethanol extract also prolonged ejaculatory latency. The testosterone and cholesterol concentrations were also increased as the dose increased particularly on day 1 and 7. The lowest dose of 100 mg/kg showed the best aphrodisiac effect. The toxicity studies showed that there were no acute behavioural changes with zero mortality. CONCLUSION: The increased blood testosterone and cholesterol concentrations by the ethanol extract of A. barbadensis can probably be said to be the possible mechanisms of action for its aphrodisiac property. The plant may also be used to treat hypotestosteronemia following its ability to increase testosterone. These findings therefore give backing to the acclaimed local use of A. barbadensis root as an aphrodisiac in males.