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1.
Malar J ; 23(1): 103, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38609987

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=1.


Subject(s)
Antimalarials , Artemisinins , Malaria , Maytenus , Adult , Humans , Male , Antimalarials/pharmacology , Electrocardiography , Healthy Volunteers , Malaria/drug therapy , Tanzania , Volunteers , Young Adult , Middle Aged
2.
Malar J ; 22(1): 372, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38062464

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.


Subject(s)
Antimalarials , Glucosephosphate Dehydrogenase Deficiency , Malaria, Falciparum , Malaria, Vivax , Malaria , Parasites , Humans , Animals , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Primaquine/adverse effects , Glucosephosphate Dehydrogenase Deficiency/epidemiology , Glucosephosphate Dehydrogenase Deficiency/genetics , Glucosephosphate Dehydrogenase Deficiency/diagnosis , Antimalarials/therapeutic use , Glucosephosphate Dehydrogenase/genetics , Tanzania/epidemiology , Prevalence , Cross-Sectional Studies , Retrospective Studies , Malaria/drug therapy , Malaria, Falciparum/prevention & control , Hemolysis , Malaria, Vivax/epidemiology , Malaria, Vivax/drug therapy
3.
Trop Med Infect Dis ; 7(12)2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36548651

ABSTRACT

BACKGROUND: Though Maytenus senegalensis is one of the medicinal plants widely used in traditional medicine to treat infectious and inflammatory diseases in Africa, there is a lack of safety data regarding its use. Therefore, the study aimed to asselss the safety and tolerability of the antimalarial herbal remedy M. senegalensis. MATERIAL AND METHODS: The study design was an open-label, single-arm, dose-escalation. Twelve eligible male healthy Tanzanians aged 18 to 45 years were enrolled in four study dose groups. Volunteers' safety and tolerability post-investigational-product administration were monitored on days 0 to 7,14, and 56. RESULTS: There were no deaths or serious adverse events in any of the study groups, nor any adverse events that resulted in premature discontinuation. The significant mean changes observed in WBC (p = 0.003), Neutrophils (p = 0.02), Lymphocytes (p = 0.001), Eosinophils (p = 0.009), Alanine aminotransferase (p = 0.002), Creatinine (p = 0.03) and Total bilirubin (p = 0.004) laboratory parameters were not associated with any signs of toxicity or clinical symptoms. CONCLUSIONS: M. senegalensis was demonstrated to be safe and tolerable when administered at a dose of 800 mg every eight hours a day for four days. This study design may be adapted to evaluate other herbal remedies.

4.
East Afr Health Res J ; 6(1): 98-105, 2022.
Article in English | MEDLINE | ID: mdl-36424944

ABSTRACT

Background: We have developed Nano Maji (NMM) filter system for water treatment which is currently being evaluated in a definitive cluster randomised controlled trial. Objectives: This paper descriptively presents the baseline status of one-week incidence and prevelence of diarrhoea water, sanitation and hygiene and their determinants. Methods: Recruited households in the three villages of Geita district were allocated to either intervention (NNM filter system) or control (usual practice). The primary outcome of the trial is to reduce episodes of diarrhoea at 6 months post-randomisation. Secondary outcomes are to improve water, sanitation and hygiene (WASH) status. Although households were sampled, individuals living in the selected households are used as unit of analysis for estimation of prevalence and incidence of diarrhea. Results: A total of 1,281 individuals (1,070 above 5 years and 211 under the age of 5 year children) lived in 186 households (7 individuals per household). The reported one-week prevalence and incidence of diarrhea was 10.8% and 8.4% respectively. Children under the age of five years had high incidence (22.7%) of diarrhea than individuals aged 5 years and above (5.6%). Among under five children, boys had high incidence and prevalence of diarrhea than girls. Individuals with diarrhea were likely to live in poor household, not using safe water and toilet. Over 70% of households had unacceptable latrines 135 (72.7%) and poor water situation 138 (74.3%) in terms of practice of storing, treating and drawing water from storage container. Majority of respondents had limited knowledge on handwashing and rarely used soap when washing hands. Conclusion: Substantial proportion of individuals living in project areas are affected by diarrhea. Children below the age of five years are more affected than individuals aged five years and above. The baseline findings are representative of local status of WASH, and reflects the prevailing poor water, sanitation and hygiene status in rural areas of Tanzania. Trial approval number NIMR/HQ/R.8a/Vol. IX/3045.

5.
PLoS One ; 17(7): e0271828, 2022.
Article in English | MEDLINE | ID: mdl-35862395

ABSTRACT

BACKGROUND: The success of any randomized clinical trial relies on the willingness of people to be recruited in the trial. However, 90% of all clinical trials worldwide have been reported to have failed to recruit the required number of trial participants within the scheduled time. This study aimed to qualitatively explore the motivations and barriers for healthy participants to participate in herbal remedy clinical trials in Tanzania. MATERIALS AND METHODS: This study used a qualitative descriptive research design based on the theory of planned behaviour. A total of five Focus Group Discussions (FGD) were conducted at Bagamoyo Clinical Trial Facility from 29 to 30 May 2021. Each group consisted of 5 to 10 participants. The participants of the study were 30 healthy males aged 18 to 45 male who participated in the clinical trial that evaluated the safety, tolerability, and efficacy of Maytenus Senegalensis. The focus group discussions were recorded audio-recorded. Verbatim transcription and thematic analysis were performed on the data. RESULTS: The prominent motivations mentioned were the opportunity for self-development, altruism, flexible study visit schedule, and financial compensation. Furthermore, the Participants' mothers and friends were reported as those most likely to approve of participation in an herbal remedy. The most mentioned barriers were inconvenience related to time commitment requirements, possible side effects, inflexible study visit schedule, and having other commitments. Moreover, the participants' father was reported to be more likely to disapprove of participation in a clinical trial of herbal remedy clinical trial. CONCLUSIONS: The results of this study showed that the motivations and barriers of healthy participants to participate in clinical trials of herbal remedies are varied and that participants are motivated by more than financial gains. The identified motivations and barriers can be used as a guideline to improve the design of recruitment and retention strategies for herbal remedy clinical trials.


Subject(s)
Motivation , Focus Groups , Healthy Volunteers , Humans , Male , Qualitative Research , Tanzania
6.
Malar J ; 20(1): 58, 2021 Jan 22.
Article in English | MEDLINE | ID: mdl-33482835

ABSTRACT

BACKGROUND: Precise detection of Plasmodium infections in community surveys is essential for effective malaria control. Microscopy and rapid diagnostic tests (RDTs) are the major techniques used to identify malaria infections in the field-based surveys. Although microscopy is still considered as the gold standard, RDTs are increasingly becoming versatile due to their rapid and adequate performance characteristics. METHODS: A malaria prevalence cross-sectional survey was carried out in north-western Tanzania in 2016, aimed at appraising the performance of high sensitivity Plasmodium falciparum (HSPf) tests compared to SD Bioline Pf and microscopy in detecting P. falciparum infections. A total of 397 individuals aged five years and above were tested for P. falciparum infections. The sensitivity, specificity, positive, and negative predictive values (PPV and NPV) of microscopy, Pf RDT and HSPf RDT was determined using PCR as the gold standard method. RESULTS: The prevalence of P. falciparum infections determined by microscopy, SD Bioline Pf, HSPf and PCR was 21.9, 27.7, 33.3 and 43.2%, respectively. The new HSPf RDT had significantly higher sensitivity (98.2%) and specificity (91.6%) compared to the routinely used SD Bioline Pf RDT(P < 0.001). The positive predictive value (PPV) was 81.8% and the negative predictive value (NPV) was 99.2% for the routinely used SD Bioline Pf RDT. Moreover, HSPf RDT had sensitivity of 69% and specificity of 76.8% compared to microscopy. The PPV was 45.5% and the NPV was 89.8% for microscopy. Furthermore, the analytical sensitivity test indicated that the newly developed HSPf RDT had lower detection limits compared to routinely used SD Bioline RDT. CONCLUSIONS: HSPf RDT had better performance when compared to both microscopy and the currently used malaria RDTs. The false negativity could be associated with the low parasite density of the samples. False positivity may be related to the limitations of the expertise of microscopists or persistent antigenicity from previous infections in the case of RDTs. Nevertheless, HS PfRDT performed better compared to routinely used Pf RDT, and microscopy in detecting malaria infections. Therefore, HS Pf RDT presents the best alternative to the existing commercial/regularly available RDTs due to its sensitivity and specificity, and reliability in diagnosing malaria infections.


Subject(s)
Antigens, Protozoan/genetics , Malaria, Falciparum/diagnosis , Pathology, Molecular/standards , Plasmodium falciparum/genetics , Protozoan Proteins/genetics , Adolescent , Adult , Child , Cross-Sectional Studies , Female , Humans , Malaria, Falciparum/epidemiology , Malaria, Falciparum/parasitology , Male , Microscopy/standards , Pathology, Molecular/instrumentation , Pathology, Molecular/methods , Polymerase Chain Reaction/standards , Predictive Value of Tests , Prevalence , Reproducibility of Results , Sensitivity and Specificity , Tanzania , Young Adult
7.
Nat Prod Bioprospect ; 8(1): 63-69, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29357092

ABSTRACT

The Phytochemical investigation on MeOH extract on the bark of Aristolochia brasiliensis Mart. & Zucc (Aristolochiaceae) led to the isolation of major compound (1) as light brown grainy crystals. The compound was identified as 1-(4-hydroxybenzyl)-1,2,3,4-tetrahydroisoquinoline-6,7-diol (higenamine) on the basis of spectroscopic analysis, including 1D and 2D NMR spectroscopy. The compound was evaluated for its antimycobacterial activity against Mycobacterium indicus pranii (MIP), using Galleria mellonella larva as an in vivo infection model. The survival of MIP infected larvae after a single dose treatment of 100 mg/kg body weight of higenamine was 80% after 24 h. Quantitatively the compound exhibited a dose dependent activity, as evidenced by the reduction of colony density from 105 to 103 CFU for test concentrations of 50, 100, 150 and 200 mg/kg body weight respectively. The IC50 value for higenamine was 161.6 mg/kg body weight as calculated from a calibration curve. Further analysis showed that, a complete inhibition of MIP in the G. mellonella could be achieved at 334 mg/kg body weight. Despite the fact that MIP has been found to be highly resistant against isoniazid (INH) in an in vitro assay model, in this study the microbe was highly susceptible to this standard anti-TB drug. The isolation of higenamine from the genus Aristolochia and the method used to evaluate its in vivo antimycobacterial activity in G. mellonella are herein reported for the first time.

8.
Molecules ; 22(10)2017 Oct 13.
Article in English | MEDLINE | ID: mdl-29027985

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-octadecahydropicene-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)-α, and interferon (IFN)-γ 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.


Subject(s)
HIV Infections/drug therapy , HIV-1/drug effects , Triterpenes/administration & dosage , Virus Activation/drug effects , Gene Expression Regulation, Viral/drug effects , HIV Infections/genetics , HIV Infections/virology , HIV-1/genetics , Histone Deacetylases/genetics , Humans , Interleukin-2/genetics , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/virology , Ocimum/chemistry , Triterpenes/chemistry , Tumor Necrosis Factor-alpha/genetics
9.
BMC Complement Altern Med ; 16(1): 282, 2016 Aug 11.
Article in English | MEDLINE | ID: mdl-27514380

ABSTRACT

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.


Subject(s)
Diabetes Mellitus/therapy , Medicine, Traditional , Adolescent , Adult , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Tanzania , Young Adult
10.
BMC Nephrol ; 16: 170, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-26499070

ABSTRACT

BACKGROUND: In sub-Saharan Africa, chronic kidney disease (CKD) is being recognized as a non-communicable disease (NCD) with high morbidity and mortality. In countries like Tanzania, people access many sources, including traditional medicines, to meet their healthcare needs for NCDs, but little is known about traditional medicine practices among people with CKD. Therefore, we sought to characterize these practices among community members with CKD in northern Tanzania. METHODS: Between December 2013 and June 2014, we administered a previously-developed survey to a random sample of adult community-members from the Kilimanjaro Region; the survey was designed to measure traditional medicine practices such as types, frequencies, reasons, and modes. Participants were also tested for CKD, diabetes, hypertension, and HIV as part of the CKD-AFRiKA study. To identify traditional medicines used in the local treatment of kidney disease, we reviewed the qualitative sessions which had previously been conducted with key informants. RESULTS: We enrolled 481 adults of whom 57 (11.9 %) had CKD. The prevalence of traditional medicine use among adults with CKD was 70.3 % (95 % CI 50.0-84.9 %), and among those at risk for CKD (n = 147; 30.6 %), it was 49.0 % (95 % CI 33.1-65.0 %). Among adults with CKD, the prevalence of concurrent use of traditional medicine and biomedicine was 33.2 % (11.4-65.6 %). Symptomatic ailments (66.7 %; 95 % CI 17.3-54.3), malaria/febrile illnesses (64.0 %; 95 % CI 44.1-79.9), and chronic diseases (49.6 %; 95 % CI 28.6-70.6) were the most prevalent uses for traditional medicines. We identified five plant-based traditional medicines used for the treatment of kidney disease: Aloe vera, Commifora africana, Cymbopogon citrullus, Persea americana, and Zanthoxylum chalybeum. CONCLUSIONS: The prevalence of traditional medicine use is high among adults with and at risk for CKD in northern Tanzania where they use them for a variety of conditions including other NCDs. Additionally, many of these same people access biomedicine and traditional medicines concurrently. The traditional medicines used for the local treatment of kidney disease have a variety of activities, and people with CKD may be particularly vulnerable to adverse effects. Recognizing these traditional medicine practices will be important in shaping CKD treatment programs and public health policies aimed at addressing CKD.


Subject(s)
Health Knowledge, Attitudes, Practice , Medicine, African Traditional/statistics & numerical data , Plant Preparations/therapeutic use , Renal Insufficiency, Chronic/drug therapy , Adolescent , Adult , Aloe , Commiphora , Cymbopogon , Female , Humans , Male , Middle Aged , Persea , Phytotherapy/statistics & numerical data , Risk Factors , Surveys and Questionnaires , Tanzania , Young Adult , Zanthoxylum
11.
PLoS One ; 10(4): e0122638, 2015.
Article in English | MEDLINE | ID: mdl-25848762

ABSTRACT

INTRODUCTION: Traditional medicines are an important part of healthcare in sub-Saharan Africa, and building successful disease treatment programs that are sensitive to traditional medicine practices will require an understanding of their current use and roles, including from a biomedical perspective. Therefore, we conducted a mixed-method study in Northern Tanzania in order to characterize the extent of and reasons for the use of traditional medicines among the general population so that we can better inform public health efforts in the region. METHODS: Between December 2013 and June 2014 in Kilimanjaro, Tanzania, we conducted 5 focus group discussions and 27 in-depth interviews of key informants. The data from these sessions were analyzed using an inductive framework method with cultural insider-outsider coding. From these results, we developed a structured survey designed to test different aspects of traditional medicine use and administered it to a random sample of 655 adults from the community. The results were triangulated to explore converging and diverging themes. RESULTS: Most structured survey participants (68%) reported knowing someone who frequently used traditional medicines, and the majority (56%) reported using them themselves in the previous year. The most common uses were for symptomatic ailments (42%), chronic diseases (15%), reproductive problems (11%), and malaria/febrile illnesses (11%). We identified five major determinants for traditional medicine use in Northern Tanzania: biomedical healthcare delivery, credibility of traditional practices, strong cultural identities, individual health status, and disease understanding. CONCLUSIONS: In order to better formulate effective local disease management programs that are sensitive to TM practices, we described the determinants of TM use. Additionally, we found TM use to be high in Northern Tanzania and that its use is not limited to lower-income areas or rural settings. After symptomatic ailments, chronic diseases were reported as the most common reason for TM use which may be particularly important in Northern Tanzania where non-communicable diseases are a rapidly growing burden.


Subject(s)
Delivery of Health Care , Medicine, African Traditional , Adult , Female , Humans , Male , Socioeconomic Factors , Tanzania
12.
J Inflamm (Lond) ; 12: 4, 2015.
Article in English | MEDLINE | ID: mdl-25705127

ABSTRACT

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.

13.
J Nat Prod ; 75(10): 1712-6, 2012 Oct 26.
Article in English | MEDLINE | ID: mdl-23002902

ABSTRACT

Two new anti-HIV xanthones, 6,7,11-trihydroxy-10-methoxy-9-(7-methoxy-3-methyl-1-oxoisochroman-5-yl)-2-methyl-12-oxo-12H-benzo[b]xanthene-4-carboxylic acid (1) and 6,7-dihydroxy-10,11-dimethoxy-9-(7-methoxy-3-methyl-1-oxoisochroman-5-yl)-2-methyl-12-oxo-12H-benzo[b]xanthene-4-carboxylic acid (2), and a new hexadecahydrochrysen-3-ol (3) were isolated from the tubers of Pyrenacantha kaurabassana. Compounds 1 and 2 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.


Subject(s)
Anti-HIV Agents/isolation & purification , Anti-HIV Agents/pharmacology , Boraginaceae/chemistry , Xanthones/isolation & purification , Xanthones/pharmacology , Anti-HIV Agents/chemistry , HIV , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Stereoisomerism , Tanzania , Xanthones/chemistry
14.
Bioorg Med Chem Lett ; 21(23): 7085-8, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-22014830

ABSTRACT

Exposure of the phenol, (5-bromo-2-hydroxyphenyl)(2,4,5-trimethoxyphenyl)methanone 18 to ceric ammonium nitrate (CAN) resulted in the formation of 7-bromo-3,4a-dimethoxy-2H-xanthene-2,9(4aH)-dione 19 and 5-bromo-2',5'-dimethoxy-3H-spiro[benzofuran-2,1'-cyclohexa[2,5]diene]-3,4'-dione 20. The brominated spirobenzofuran 20 was then subjected to Suzuki-Miyaura reactions to give six derivatives 22a-f. These compounds, related diones and xanthones displayed mostly noteworthy antimicrobial activity, particularly towards the yeasts Cryptococcus neoformans and Candida albicans. Diones 15 and 30 displayed significant activity (7.8 µg/mL) against C. albicans and C. neoformans, respectively. Furthermore, dione 10 displayed the most significant activity (3.6 µg/mL) against both yeasts.


Subject(s)
Benzofurans/chemical synthesis , Benzofurans/pharmacology , Candida albicans/drug effects , Cryptococcus neoformans/drug effects , Spiro Compounds/chemical synthesis , Spiro Compounds/pharmacology , Xanthones/chemical synthesis , Xanthones/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Benzofurans/chemistry , Benzoquinones/chemical synthesis , Benzoquinones/chemistry , Benzoquinones/pharmacology , Molecular Structure , Spiro Compounds/chemistry , Xanthones/chemistry
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