Antioxidant and anti-inflammatory activity of Ocimum labiatum extract and isolated labdane diterpenoid

BACKGROUND : Plants from the genus Ocimum are used as folk medicine for treating various diseases including inflammatory and immune-related diseases. Numerous reports have suggested plant extracts and their constituents as possible anti-inflammatory agents. Here, in vitro evidence of Ocimum labiatum’s immune-enhancing and antioxidant properties is presented for the first time. METHODS : The anti-inflammatory effect of O. labiatum ethanolic extract and an isolated diterpenoid was determined using a cytometric bead array (CBA) technique. The effect on phytohemagglutinin (PHA)-induced nitric oxide (NO) production in peripheral blood mononuclear cells (PBMCs) was also assessed. A battery of antioxidant assays were used for detecting antioxidant activity while the anti-inflammatory mechanism was evaluated using an ELISA-based activator protein (AP-1) (c-Jun) assay. Cytotoxicity was determined on TZM-bl and PBMCs using a tetrazolium dye and confirmed by a novel label-free real-time assay. RESULTS : A 25 μg/mL non-cytotoxic concentration of O. labiatum extract significantly (p < 0.05) inhibited the production of pro-inflammatory cytokines; IL-2, IL-4, IL-6 and IL-17A. Except for the dual acting pro- or anti-inflammatory cytokine, IL-6, which was upregulated, a non-cytotoxic 50 μM concentration of the isolated labdane diterpenoid compound significantly (p < 0.05) decreased the production of all the pro-inflammatory cytokines. In the anti-inflammatory pathway studies, the compound also inhibited AP-1 significantly (p < 0.05) at 50 μM. The extract demonstrated strong, dose dependent antioxidant activity with IC50 values ranging from 13 ± 0.8 to 54.86 ± 1.28 μg/mL while the terpene had no antioxidant property. The extract and diterpenoid decreased the production of the inflammatory mediator NO, at non-cytotoxic concentrations. The CC50 of the extract in TZM-bl and PBMCs was 62.6 ± 0.6 and 30.1 ± 0.4 μg/mL while that of the compound was 112.6 ± 0.2 and 70 ± 0.4 μM respectively. The real time studies confirmed tetrazolium dye assessed viability and also detected a unique growth pattern for the plant materials compared to untreated cells. CONCLUSIONS : O. labiatum extract demonstrated promising anti-inflammatory and antioxidant properties while the terpenoid showed anti-inflammatory but no antioxidant activity. The anti-inflammatory mechanism of the terpene was a result of inhibition of AP-1. These data represents promising first steps towards the development of naturally derived anti-inflammation drugs.Southern African Biochemistry and Informatics for Natural Products (SABINA), the Technology Innovation Agency (TIA, South Africa), Margaret McNamara Memorial Fund (MMMF), the Namibian Ministry of Education and the University of Pretoria.http://www.journal-inflammation.comhb2016Biochemistr

In vitro Antimycobacterial Activity of Sterculia quinqueloba (Garcke) K. Schumand Canthium crassum Hiern

This research article published European Journal of Medicinal Plants, 2015Aim: To screen for the anti-mycobacterial activity of Canthium crassum and Sterculia quinqueloba using two mycobacteria species the Mycobacteria madagascariense and Mycobacteria indicuspranii. Study Design: In vitro assay of anti-mycobacterial assay was done using 96-well micro-dilution method. Place and Duration of Study: School of Life Science and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania, from April 2014 to June 2014. Methodology: 96-well-microtitre serial micro-dilution method was used to determine anti-mycobacteria activity to plant extracts. Results: All extracts exhibited anti-mycobacterial activity to both mycobacteria tested. The minimum inhibition concentration (MIC) ranged from 0.39 – 12.5 mg/mL, with ethyl acetate leaf extract of S. quinqueloba being the most active extracts with MIC value of 0.39 mg/mL against Mycobacteria madagascariense (MM) and 0.78 mg/mL against Mycobacteria indicuspranii (MIP). Petroleum ether and ethyl acetate leaf extract of C. crassum also gave MIC value of 0.78 mg/mL against MM and MIP. Conclusion: Findings from the present study showed that both plants exhibited activity against mycobacterium species tested. These plants may therefore serve as a source for new ant-mycobacterium drugs worth further studies including isolation and identification of the active compounds

Traditional Medicine Practices among Community Members with Diabetes Mellitus in Northern Tanzania: An ethnomedical Survey.

Diabetes is a growing burden in sub-Saharan Africa where traditional medicines (TMs) remain a primary form of healthcare in many settings. In Tanzania, TMs are frequently used to treat non-communicable diseases, yet little is known about TM practices for non-communicable diseases like diabetes. Between December 2013 and June 2014, we assessed TM practices, including types, frequencies, reasons, and modes, among randomly selected community members. To further characterize TMs relevant for the local treatment of diabetes, we also conducted focus groups and semi-structured interviews with key informants. We enrolled 481 adults of whom 45 (9.4 %) had diabetes. The prevalence of TM use among individuals with diabetes was 77.1 % (95 % CI 58.5-89.0 %), and the prevalence of using TMs and biomedicines concurrently was 37.6 % (95 % CI 20.5-58.4 %). Many were using TMs specifically to treat diabetes (40.3 %; 95 % CI 20.5-63.9), and individuals with diabetes reported seeking healthcare from traditional healers, elders, family, friends, and herbal vendors. We identified several plant-based TMs used toward diabetes care: Moringa oleifera, Cymbopogon citrullus, Hagenia abyssinica, Aloe vera, Clausena anisata, Cajanus cajan, Artimisia afra, and Persea americana. TMs were commonly used for diabetes care in northern Tanzania. Individuals with diabetes sought healthcare advice from many sources, and several individuals used TMs and biomedicines together. The TMs commonly used by individuals with diabetes in northern Tanzania have a wide range of effects, and understanding them will more effectively shape biomedical practitices and public health policies that are patient-centered and sensitive to TM preferences

Triterpenoids from ocimum labiatum activates latent HIV-1 expression in vitro : potential for use in adjuvant therapy

Abstract: Latent HIV reservoirs in infected individuals prevent current treatment from eradicating infection. Treatment strategies against latency involve adjuvants for viral reactivation which exposes viral particles to antiretroviral drugs. In this study, the effect of novel triterpenoids isolated from Ocimum labiatum on HIV-1 expression was measured through HIV-1 p24 antigen capture in the U1 latency model of HIV-1 infection and in peripheral blood mononuclear cells (PBMCs) of infected patients on combination antiretroviral therapy (cART). The mechanism of viral reactivation was determined through the compound’s effect on cytokine production, histone deacetylase (HDAC) inhibition, and protein kinase C (PKC) activation. Cytotoxicity of the triterpenoids was determined using a tetrazolium dye and flow cytometry. The isolated triterpene isomers, 3-hydroxy-4,6a,6b,11,12,14b-hexamethyl-1,2,3,4,6,6a,6b,7,8,8a,9,10,11,12,12a,14,14a,14b-octadecahydrop icene-4,8a-dicarboxylic acid (HHODC), significantly (p < 0.05) induced HIV-1 expression in a dose-dependent manner in U1 cells at non-cytotoxic concentrations. HHODC also induced viral expression in PBMCs of HIV-1 infected patients on cART. In addition, the compound up-regulated the production of interleukin (IL)-2, IL-6, tumour necrosis factor (TNF)-_, and interferon (IFN)- but had no effect on HDAC and PKC activity, suggesting cytokine upregulation as being involved in latency activation. The observed in vitro reactivation of HIV-1 introduces the adjuvant potential of HHODC for the first time here

The effect of an anti-malarial herbal remedy, Maytenus senegalensis, on electrocardiograms of healthy Tanzanian volunteers

Abstract Background The emergence of resistance to artemisinin-based combination therapy necessitates the search for new, more potent antiplasmodial compounds, including herbal remedies. The whole extract of Maytenus senegalensis has been scientifically investigated for potential biological activities both in vitro and in vivo, demonstrating strong antimalarial activity. However, there is a lack of data on the electrocardiographic effects of M. senegalensis in humans, which is a crucial aspect in the investigation of malaria treatment. Assessing the electrocardiographic effects of M. senegalensis is essential, as many anti-malarial drugs can inadvertently prolong the QT interval on electrocardiograms. Therefore, the study's objective was to evaluate the electrocardiographic effects of M. senegalensis in healthy adult volunteers. Methods This study is a secondary analysis of an open-label single-arm dose escalation. Twelve healthy eligible Tanzanian males, aged 18 to 45, were enrolled in four study dose groups. A single 12-lead electrocardiogram (ECG) was performed at baseline and on days 3, 7, 14, 28, and 56. Results No QTcF adverse events occurred with any drug dose. Only one volunteer who received the highest dose (800 mg) of M. senegalensis experienced a moderate transient change (△QTcF > 30 ms; specifically, the value was 37 ms) from baseline on day 28. There was no difference in maximum QTcF and maximum △QTcF between volunteers in all four study dose groups. Conclusions A four-day regimen of 800 mg every 8 h of M. senegalensis did not impact the electrocardiographic parameters in healthy volunteers. This study suggests that M. senegalensis could be a valuable addition to malaria treatment, providing a safer alternative and potentially aiding in the battle against artemisinin-resistant malaria. The results of this study support both the traditional use and the modern therapeutic potential of M. senegalensis. They also set the stage for future research involving larger and more diverse populations to explore the safety profile of M. senegalensis in different demographic groups. This is especially important considering the potential use of M. senegalensis as a therapeutic agent and its widespread utilization as traditional medicine. Trial registration ClinicalTrials.gov, NCT04944966. Registered 30 June 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04944966?term=kamaka&draw=2&rank=

Prevalence of G6PD deficiency and submicroscopic malaria parasites carriage in malaria hotspot area in Northwest, Tanzania

Abstract Background The use of primaquine for mass drug administration (MDA) is being considered as a key strategy for malaria elimination. In addition to being the only drug active against the dormant and relapsing forms of Plasmodium vivax, primaquine is the sole potent drug against mature/infectious Plasmodium falciparum gametocytes. It may prevent onward transmission and help contain the spread of artemisinin resistance. However, higher dose of primaquine is associated with the risk of acute haemolytic anaemia in individuals with a deficiency in glucose-6-phosphate dehydrogenase. In many P. falciparum endemic areas there is paucity of information about the distribution of individuals at risk of primaquine-induced haemolysis at higher dose 45 mg of primaquine. Methods A retrospective cross-sectional study was carried out using archived samples to establish the prevalence of G6PD deficiency in a malaria hotspot area in Misungwi district, located in Mwanza region, Tanzania. Blood samples collected from individuals recruited between August and November 2010 were genotyped for G6PD deficiency and submicroscopic parasites carriage using polymerase chain reaction. Results A total of 263 individuals aged between 0 and 87 were recruited. The overall prevalence of the X-linked G6PD A− mutation was 83.7% (220/263) wild type, 8% (21/263) heterozygous and 8.4% (22/263) homozygous or hemizygous. Although, assessment of the enzymatic activity to assign the phenotypes according to severity and clinical manifestation as per WHO was not carried out, the overall genotype and allele frequency for the G6PD deficiency was 16.4% and 13. 2%, respectively. There was no statistically significant difference in among the different G6PD genotypes (p > 0.05). Out of 248 samples analysed for submicroscopic parasites carriage, 58.1% (144/248) were P. falciparum positive by PCR. G6PD heterozygous deficiency were associated with carriage of submicroscopic P. falciparum (p = 0.029). Conclusions This study showed that 16.4% of the population in this part of North-western Tanzania carry the G6PD A− mutation, within the range of 15–32% seen in other parts of Africa. G6PD gene mutation is widespread and heterogeneous across the study area where primaquine would be valuable for malaria control and elimination. The maps and population estimates presented here reflect potential risk of higher dose of primaquine being associated with the risk of acute haemolytic anaemia (AHA) in individuals with a deficiency in glucose-6-phosphate dehydrogenase and call further research on mapping of G6PD deficiency in Tanzania. Therefore, screening and education programmes for G6PD deficiency is warranted in a programme of malaria elimination using a higher primaquine dose

Additional file 1: Appendix. of Traditional medicine practices among community members with chronic kidney disease in northern Tanzania: an ethnomedical survey

Structured Survey Instrument for the use of Traditional Medicines (English and Swahili) (DOCX 461 kb

Bioassay-Guided Investigation of the Tanzanian Plant <i>Pyrenacantha kaurabassana</i> for Potential Anti-HIV-Active Compounds

Two new anti-HIV xanthones, 6,7,11-trihydroxy-10-methoxy-9-(7-methoxy-3-methyl-1-oxoisochroman-5-yl)-2-methyl-12-oxo-12<i>H</i>-benzo­[<i>b</i>]­xanthene-4-carboxylic acid (<b>1</b>) and 6,7-dihydroxy-10,11-dimethoxy-9-(7-methoxy-3-methyl-1-oxoisochroman-5-yl)-2-methyl-12-oxo-12<i>H</i>-benzo­[<i>b</i>]­xanthene-4-carboxylic acid (<b>2</b>), and a new hexadecahydrochrysen-3-ol (<b>3</b>) were isolated from the tubers of <i>Pyrenacantha kaurabassana</i>. Compounds <b>1</b> and <b>2</b> showed moderate anti-HIV activity when tested in the deCIPhR assay on HIV virus type NL4-3, with IC₅₀ values of 21 and 2 μg/mL, respectively