Justin Jacob Omolo

Dr. Justin Jacob Omolo

Research and Development, National Institute for Medical Research, Dar es Salaam, Tanzania

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 August 2016 in BMC Complementary and Alternative Medicine
Verified
Journal Article
Open access
PDF file
JLJoseph Lunyera
Joseph Lunyera
DWDaphne Wang
Daphne Wang
VMVenance Maro
Venance Maro
FKFrancis Karia
Francis Karia
DBDavid Boyd
David Boyd
JSJohn W. Stanifer
John W. Stanifer
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.

23 October 2015 in BMC Nephrology
Verified
Journal Article
Open access
PDF file
JSJohn W. Stanifer
John W. Stanifer
JLJoseph Lunyera
Joseph Lunyera
DBDavid Boyd
David Boyd
FKFrancis Karia
Francis Karia
VMVenance Maro
Venance Maro
UPUptal D. Patel
Uptal D. Patel
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. 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. 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. 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.

20 January 2015 in Journal of Inflammation
Verified
Journal Article
Open access
PDF file
PKPetrina Kapewangolo
Petrina Kapewangolo
JOJustin Jacob Omolo
Justin Jacob Omolo
RBRonel Bruwer
Ronel Bruwer
PFPascaline Fru
Pascaline Fru
DMDebra Meyer
Debra Meyer
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. 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. 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. 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 October 2017 in Molecules
Verified
Journal Article
Open access
PDF file
PKPetrina Kapewangolo
Petrina Kapewangolo
JOJustin Jacob Omolo
Justin Jacob Omolo
PFPascaline Fru
Pascaline Fru
MKMartha Kandawa-Schulz
Martha Kandawa-Schulz
DMDebra Meyer
Debra Meyer
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.