Publications by authors named "Owira Peter"

Objectives: To determine the metabolic effects of tenofovir alafenamide (TAF) compared to tenofovir disoproxil fumarate (TDF) in vivo .

Design And Methods: Male Wistar rats ( Rattus novergicus , 250-300 g body weight) were divided into three groups ( n  = 8) and orally treated daily with 1.0 ml distilled water (group 1), TAF (0.

View Article and Find Full Text PDF

In this study, we synthesized and characterized ten chromenopyrimidine derivatives using analytical and spectroscopic methods. Studies on DNA and albumin binding affinity, as well as cytotoxicity tests on human breast cancer (MCF-7) cells, of the chromenopyrimidines, were conducted. The natural logarithm of the relative stability constant of DNA- and BSA-chromenopyrimidine complexes [ln(/)] was used as a criterion for selecting compounds for cytotoxicity studies.

View Article and Find Full Text PDF

Introduction: Diabetic cardiomyopathy (DCM) is an end-point macrovascular complication associated with increased morbidity and mortality in 12% of diabetic patients. MicroRNAs (miRNAs) are small noncoding RNAs that can act as cardioprotective or cardiotoxic agents in DCM.

Methods: We used PubMed as a search engine to collect and analyse data in published articles on the role of miRNAs on the pathophysiology, diagnosis and treatment of DCM.

View Article and Find Full Text PDF

Cellular senescence, a hallmark of ageing, contributes to tissue or organ dysfunction and the pathophysiology of diverse age-related diseases (ARD) by various mechanisms. Targeting it by selective elimination of senescent cells (SCs) or blocking senescence-associated secretory phenotypes (SASP) with natural or synthetic compounds has been suggested to improve lifespan. Dietary phytochemicals possess a broad spectrum of biochemical and pharmacological effects that are beneficial to human health.

View Article and Find Full Text PDF

Breast cancer (BC) is the most frequently diagnosed type of cancer as of 2020. Quercetin (Que) and Naringenin (Nar) are predominantly found in citrus fruits and vegetables and have shown promising antiproliferative effects in multiple studies. It is also known that the bioactive effects of these flavonoids are more pronounced in whole fruit than in isolation.

View Article and Find Full Text PDF

Ethnopharmacological Relevance: Psidium guajava L. leaves are used to treat diabetes in South African folkloric medicine and in other parts of the world. Psidium x durbanensis Baijnath & Ramcharun ined.

View Article and Find Full Text PDF

Metformin is the most commonly prescribed oral antidiabetic medication. Direct/indirect activation of Adenosine Monophosphate-activated protein kinase (AMPK) and non-AMPK pathways, amongst others, are deemed to explain the molecular mechanisms of action of metformin. Metformin is an established insulin receptor sensitising antihyperglycemic agent, is highly affordable, and has superior safety and efficacy profiles.

View Article and Find Full Text PDF

Objectives: Antioxidant and anti-inflammatory properties of naringenin could confer hepatoprotective effects.

Methods: Chang cells in culture media were maintained at 37°C and treated with increased concentrations of glucose (5.5-50 mm) and/or naringenin (25-100 µm), respectively, for 24 h.

View Article and Find Full Text PDF

Naringenin possesses many pharmacological effects and may modulate metformin disposition. The purpose of this study was to evaluate the role of naringenin on hepatic expression of organic cation transporter 1 (OCT1) protein and its associated effects on metformin-associated hyperlactataemia in diabetes. Forty-nine male Sprague Dawley rats randomly assigned to seven groups (n = 7) were orally treated daily with 3.

View Article and Find Full Text PDF

Background: One of the most challenging health problems is liver disease, which can be caused by medications, toxic substances, and excessive consumption of alcohol. Liver problems can be also caused by infections, autoimmune disorders, and food. This study aims to establish evidence of the use of Moringa oleifera in sub-Saharan African countries to manage liver damage conditions in animals.

View Article and Find Full Text PDF

Background: Metformin is one of the most commonly used drugs for type 2 diabetes mellitus (T2DM). Despite its efficacy and safety, metformin is frequently associated with highly variable glycemic responses, which is hypothesized to be the result of genetic variations in its transport by organic cation transporters (OCTs). This systematic review aims to highlight and summarize the overall effects of OCT1 polymorphisms on therapeutic responses to metformin and to evaluate their potential role in terms of interethnic differences with metformin responses.

View Article and Find Full Text PDF

Background: Metformin is one of the most commonly used drugs for the treatment of type 2 diabetes mellitus (T2DM). Despite its widespread use, there are considerable interindividual variations in metformin response, with about 35% of patients failing to achieve initial glycemic control. These variabilities that reflect phenotypic differences in drug disposition and action may indeed be due to polymorphisms in genes that regulate pharmacokinetics and pharmacodynamics of metformin.

View Article and Find Full Text PDF

Metformin, routinely used as first-line drug in the treatment of type 2 diabetes, has been shown to have cardioprotective effects beyond its glycemic control. These have been attributed to increases in Akt concentrations and activation of protein kinases in the RISK pathways, which prevent the mPTP from opening and rupturing it and therefore, protects myocyte viability. In myocardial infarction and subsequent reperfusion, metformin activation of AMPK promotes glycolysis and keeps the mPTP closed.

View Article and Find Full Text PDF

Background: Insulin resistance, glucose intolerance and overt diabetes are known metabolic complications associated with chronic use of HIV-Protease Inhibitors. Naringin is a grapefruit-derived flavonoid with anti-diabetic, anti-dyslipidemia, anti-inflammatory and anti-oxidant activities.

Objectives: The study investigated the protective effects of naringin on glucose intolerance and impaired insulin secretion and signaling in vivo.

View Article and Find Full Text PDF

Metformin is a widely used drug for the treatment of type 2 diabetes (T2D). Its blood glucose-lowering effects are initially due to inhibition of hepatic glucose production and increased peripheral glucose utilization. Metformin has also been shown to have several beneficial effects on cardiovascular risk factors and it is the only oral antihyperglycaemic agent thus far associated with decreased macrovascular complications in patients with diabetes.

View Article and Find Full Text PDF

Introduction: The protective effects of grapefruit-derived naringin against HIV-1 Protease Inhibitors (PIs)-associated oxidative damage to pancreatic β-cells and apoptosis were investigated in RIN-5F cells in culture.

Methods: Cells in culture medium were challenged with 11-25 mM glucose with or without nelfinavir (1-10 μM), saquinavir (1-10 μM) and atazanavir (5-20 μM), respectively for 24 h to determine insulin secretion. The cells were further treated with nelfinavir (10 μM), saquinavir (10 μM), atazanavir (20 μM) with and without naringin or glibenclamide (10 μM) for 24 h to determine insulin secretion, lipid peroxidation, Superoxide Dismutase (SOD) activity, glutathione (GSH) levels, ATP production and caspase-3 and-9 activities, respectively.

View Article and Find Full Text PDF

Background: Mitochondrial reactive oxygen species (ROS) generation and defective oxidative phosphorylation (OXPHOS) have been proposed as possible mechanisms underlying the development of nucleoside reverse transcriptase inhibitors (NRTIs)-induced mitochondrial toxicities. Available options in managing these complications have, so far, produced controversial results, thus necessitating further research into newer agents with promise. Antioxidant and free-radical scavenging effects of naringin, a plant-derived flavonoid, have previously been demonstrated.

View Article and Find Full Text PDF

Background: Hypoglycemic effects of grapefruit juice are well known but the effects of naringin, its main flavonoid on glucose intolerance and metabolic complications in type 1 diabetes are not known.

Objectives: To investigate the effects of naringin on glucose intolerance, oxidative stress and ketonemia in type 1 diabetic rats.

Methods: Sprague-Dawley rats divided into 5 groups (n = 7) were orally treated daily with 3.

View Article and Find Full Text PDF

Introduction: Hyperglycemia promotes myocardial fibrotic lesions through upregulation of PKC and p38 in response to redox changes. The effects of naringin on hyperglycemia-induced myocardial fibrotic changes and its putative effects on PKC-β and p38 protein expression in type 1 rat model of diabetes are hereby investigated.

Methods: Male Sprague-Dawley rats were divided into six groups I-VI.

View Article and Find Full Text PDF

Nucleoside Reverse Transcriptase Inhibitors (NRTIs) have not only improved therapeutic outcomes in the treatment of HIV infection but have also led to an increase in associated metabolic complications of NRTIs. Naringin's effects in mitigating NRTI-induced complications were investigated in this study. Wistar rats, randomly allotted into seven groups (n = 7) were orally treated daily for 56 days with 100 mg/kg zidovudine (AZT) (groups I, II III), 50 mg/kg stavudine (d4T) (groups IV, V, VI) and 3 mL/kg of distilled water (group VII).

View Article and Find Full Text PDF

Cardiac hypertrophy (CH) in type 1 diabetes mellitus is attributed to increased oxidative stress-associated activation of c-Jun Nuclear Kinase (JNK). We investigated the effects of naringin on hyperglycemia-associated oxidative stress, activation of JNK-1, and CH. Male Sprague-Dawley rats (225-250 g) (n = 7) were divided into 6 groups.

View Article and Find Full Text PDF

Purpose: Hypoglycemic effects of grapefruit juice (GFJ) are widely recognized, but the mechanism(s) by which GFJ lowers blood glucose levels have not previously been investigated.

Methods: Wistar rats [250-300 g body weight (BW)] were divided into eight groups (n = 7). Group 1 animals were orally treated with 3.

View Article and Find Full Text PDF

A plethora of ethnotherapeutic properties and pharmacological actions have been attributed to Sclerocarya birrea (family: Anacardiaceae). It is one of the most highly valued indigenous trees of southern Africa. Reports in biomedical literature have indicated the presence of medicinally-important chemical constituents in the plant, notably: polyphenols, tannins, coumarins, flavonoids, triterpenoids, phytosterols, and so forth.

View Article and Find Full Text PDF

The traditional uses, therapeutic attributes, phytochemical and pharmacological profiles of 'African potato' (Hypoxis hemerocallidea corm) extracts have been reviewed. Available biomedical evidence suggests that 'African potato' is a potential plant-medicine for some modern and 21st century diseases of mankind. Thus far, biomedical evidence has revealed that 'African potato' extracts possess antiinflammatory, antineoplastic, antioxidant, antidiabetic and antiinfective properties in vivo and in vitro.

View Article and Find Full Text PDF