Ademola Ayeleso

Modulation of antioxidant status in streptozotocin-induced diabetic male wistar rats following intake of red palm oil and/or rooibos

OBJECTIVE To investigate the role of red palm oil (RPO), rooibos tea extract (RTE) and their combined treatment (RPO + RTE) on antioxidant status in streptozotocin (STZ)-induced diabetic rats. METHODS Diabetes mellitus was induced by a single administration of streptozotocin (50 mg/kg) and the rats were treated for 7 weeks. Antioxidant enzymes [catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD)], antioxidant capacity [trolox equivalence antioxidant capacity (TEAC), oxygen radical absorbance capacity (ORAC)] as well as total protein, albumin, globulin, total glutathione, conjugated diene and thiobarbituric acid reactive substances (TBARS) were investigated. RESULTS Treatment with RPO, RTE and RPO + RTE significantly (p>0.05) improved liver SOD and plasma ORAC in the diabetic rats. Similarly, diabetic rats treated with RTE and RPO + RTE enhanced liver GPx. A significant (P<0.05) increase in the plasma TBARS in the diabetic control group was observed when compared with the normal control group. Treatment of diabetic rats with RTE and RPO + RTE reduced plasma TBARS to a level not significantly different at P<0.05 from the normal control group. CONCLUSIONS The results revealed the anti-oxidative potentials of red palm oil, rooibos and their combination in diabetic conditions and hence, they could be useful in the management of diabetes and its complications.

In Vitro Study on the Antioxidant Potentials of the Leaves and Fruits of Nauclea latifolia

This study was carried out to investigate the in vitro antioxidant potentials of the leaves and fruits of Nauclea latifolia, a straggling shrub or small tree, native to tropical Africa and Asia. Hot water extracts of the leaves and fruits of Nauclea latifolia were assessed for their total polyphenolic, flavanol, and flavonol contents as well as 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability, ferric reducing antioxidant power (FRAP), Trolox equivalence antioxidant capacity (TEAC), and oxygen radical absorbance capacity (ORAC) assays. The aqueous extract of the leaves was found to contain higher level of total polyphenols (11.63 ± 0.023 mg GAE/g), flavanol (1.45 ± 0.10 mg CE/g), and flavonol (2.22 ± 0.37 mg QE/g) than the extract of the fruits with values of 1.75 ± 0.02 mg GAE/g (total polyphenol), 0.15 ± 0.01 mg CE/g (flavanol), and 1.00 ± 0.13 mg QE/g (flavonol). Similarly, the aqueous extract of the leaves also exhibited higher DPPH (IC50 20.64 mg/mL), FRAP (86.10 ± 3.46 μmol AAE/g), TEAC (94.83 ± 3.57 μmol TE/g), and ORAC (196.55 ± 0.073 μmol TE/g) than the extract of the fruits with DPPH (IC50 120.33 mg/mL), FRAP (12.23 ± 0.40 μmol AAE/g), TEAC (12.48 ± 0.21 μmol TE/g), and ORAC (58.88 ± 0.073 μmol TE/g). The present study showed that Nauclea latifolia has strong antioxidant potentials with the leaves demonstrating higher in vitro antioxidant activities than the fruits.

Effects of dietary intake of red palm oil on fatty acid composition and lipid profiles in male Wistar rats

Little is known about the effects of the dietary intake of red palm oil (RPO) on fatty acid composition in the liver of rats. Male Wistar rats randomly divided into four groups were fed with different doses of red palm oil. The control group received no red palm oil; while the experimental groups were fed with 1 ml, 2 ml and 4 ml of red palm oil daily for seven weeks. In the liver of all the groups, palmitic acid (C16:0) followed by stearic acid (C18:0) were predominantly present among the saturated fatty acids. Oleic acid (C18:1c) and linoleic acid (C18:2) were largely present among the unsaturated fatty acids. There was no significant (P<0.05) increase in the levels of palmitic acid (C16:0) in all the groups while oleic acid (C18:1) significantly increased at 4 ml RPO when compared with the control (p<0.05). The total cholesterol (TC), triglycerides (TG) and very low-density lipoprotein (VLDL)-cholesterol levels were not significantly different in all the groups (P<0.05) when compared with the control group. Generally, there were no significant effects of RPO on levels of serum cholesterol, and triglycerides as well as accumulation of saturated fatty acids in the liver of the experimental rats. Keywords: Lipid profiles, fatty acid, red palm oil, rats African Journal of Biotechnology Vol. 11(33), pp. 8275-8279, 24 April, 2012

A Study on Neonatal Intake of Oleanolic Acid and Metformin in Rats (Rattus norvegicus) with Metabolic Dysfunction: Implications on Lipid Metabolism and Glucose Transport

Metabolic syndrome, a cluster of different disorders which include diabetes, obesity and cardiovascular diseases, is a global epidemic that is growing at an alarming rate. The origins of disease can be traced back to early developmental stages of life. This has increased mortalities and continues to reduce life expectancies of individuals across the globe. The aim of this study was to investigate the sub-acute and long term effects of neonatal oral administration of oleanolic acid and metformin on lipids (free fatty acids, FFAs) and genes associated with lipid metabolism and glucose transport using a neonatal rat experimental model. In the first study, seven days old pups were randomly grouped into control—distilled water (DW); oleanolic acid (60 mg/kg), metformin (500 mg/kg), high fructose diet (20% w/v, HF), oleanolic acid (OA) + high fructose diet (OA + HF), and Metformin + high fructose diet (MET + HF) groups. The pups were treated for 7 days, and then terminated on postnatal day (PD) 14. In the second study, rat pups were initially treated similarly to study 1 and weaned onto normal rat chow and plain drinking water on PD 21 till they reached adulthood (PD112). Tissue and blood samples were collected for further analyses. Measurement of the levels of free fatty acids (FFAs) was done using gas chromatography-mass spectrometry. Quantitative polymerase chain reaction (qPCR) was used to analyze the gene expression of glut-4, glut-5, fas, acc-1, nrf-1 and cpt-1 in the skeletal muscle. The results showed that HF accelerated accumulation of saturated FFAs within skeletal muscles. The HF fed neonatal rats had increased stearic acid, which was associated with decreased glucose, suppressed expression of glut-4, glut-5, nrf-1 and cpt-1 genes, and increased expression of acc-1 (p < 0.01) and fas. OA + HF and MET + HF treated groups had increased mono- and polyunsaturated FFAs; oleic, and octadecadienoic acids than the HF group. These unsaturated FFAs were associated with increased glut-4, glut-5 and nrf-1 (p < 0.01) and decreased acc-1 and fas (p < 0.05) in both OA + HF and MET + HF treated groups. Conclusions: The present study shows that neonatal oral administration of oleanolic acid and metformin potentially protects against the development of fructose-induced metabolic dysfunction in the rats in both short and long time periods.

Hybrid compounds from thiosemicarbazone and triazole as antidiabetic agents and their antioxidant potentials

W it is estimated that 220 million people suffer from Diabetes Mellitus and among all the diabetic patients, almost 90% suffer of Type 2 Diabetes. Twenty one million people in the United States, accounting for 7 % of the population, have Diabetes Mellitus (DM) according to the American Diabetes Association (ADA). One third of these people are not aware that they are diabetic as another 41 million people are pre‐diabetic. The total economic cost annually of Diabetes is approximately 132 billion dollars. Diabetes is more frequent among African Americans, Hispanic Americans, American Indians and Asian/Pacific Islanders. In people age 20 and older, 9.6% have Diabetes and in patients of 60 years or older 20.9 % have Diabetes. Diabetes is the sixth leading cause of death in the U.S, according to the center for disease control and prevention (CDC). The widespread occurrence of obesity supports the projection that cases of Diabetes will continue to grow. Diabetes causes a significant economic burden both in terms of direct and indirect costs to society. It is also responsible for increased morbidity and mortality. Three metabolic defects are responsible for the progression to Type 2 Diabetes Mellitus: peripheral insulin resistance, impaired -cell function, and increased hepatic glucose production. In modern age medicine, treatments are available for Diabetes Mellitus like Sulfonylureas, GLP-1 agonists, DPP4 inhibitors, PPAR-γ agonists, GPR119 agonists and SGLT2 inhibitors. The thiazolidinediones are a new class of agents that have been developed to treat Type 2 diabetic patients. Pioglitazone hydrochloride acts as an agonist at peroxisome proliferator-activated receptors (PPARs) in target tissues for insulin action, such as adipose tissue, skeletal muscle, and liver. Activation of the PPAR-g regulates the transcription of insulin-responsive genes involved in the control of glucose production, transport, and utilization. In this manner, it enhances tissue sensitivity to insulin. Since there is a decrease in solubility with increase in pH and the half life being 3-5 hrs, so is incomplete absorption and eliminated quickly from the conventional tablets. Pioglitazone hydrochloride being a nonpolar drug and cannot effectively break down the lattice structure of water and hence its aqueous solubility is low. The objective of the present research work was to perform solubility studies in various oils and surfactants along with the cosolvents and to develop an optimum SEDDS for Pioglitazone HCl. SEDDS were characterized for size and zeta potential and in-vivo studies were performed to assess the bioavailability. Pioglitazone, a widely prescribed anti diabetic drug belongs to class IΙ under BCS and exhibit low and variable oral bioavailability due to its poor aqueous solubility. Its oral absorption is dissolution rate limited and it requires enhancement in the solubility and dissolution rate for increasing its oral bioavailability. The rate and extent of release of pioglitazone Hcl from stable SEDDS (F1) was high in 1% SLS when compared to SGF. The FTIR spectra proved that there was on chemical interaction between excipients and drug. SEM studies confirmed that the size was small and spherical.Diabetes mellitus is a metabolic disease that threatens and reduces the quality of life. Eight hybrids (1ah) of thiosemicarbozone and triazole were screened for their effects on genes related to type 2 diabetes as well as their antioxidant activity. The influence of the hybrids on glucose transport genes (Glut-4, Mef2a and Nrf-1) was carried out using quantitative real time polymerase chain reaction (PCR). Antioxidant assays were carried out using established techniques. Hybrids 1b, 1d, 1e and 1g exhibited high expression of Glut-4 gene relative to insulin and control. All the hybrids tested except 1h and 1f expressed the Nrf-1 while only 1h did not express Mef-2a relative to control. Among all the compounds, 1b showed the highest 1-diphenyl-2-picryl- hydrazyl (DPPH) radical scavenging ability and Trolox Equivalent Antioxidant Capacity (TEAC) values. In terms of Ferric Reducing Antioxidant Power (FRAP) and Oxygen Radical Absorbance Capacity (ORAC), 1c and 1d had the highest values, respectively. In all the antioxidant assays carried out, 1a was shown to have the lowest antioxidant activities. Hybrids 1d and 1g showed consistent pattern of glucose transport pathway gene transcription with all the hybrids showing antioxidant potentials though at varying extents. These hybrids could be potential candidates eliciting antidiabetic and antioxidant effects.Objective: In this presentation we will give insight for novel evidence(s) raised from our research group studies in last five years about triggering central role of restoring as well as augmenting antioxidant defense by using adult bone marrow hematopoietic rich stem cells (HSCs), Silymarin (SM) and Silibinin (SB) to produce remarkable antidiabetic activities in STZ-diabetic rats. Two strategies were adopted to activate pancreatic cell therapy via possible regeneration of pancreatic cells, stimulation of β-cells, and enhancement of insulin release.

P01.50. Influence of dietary red palm oil on antioxidant status in male Wistar rats

Methods Male wistar rats were randomly divided into three groups. Group 1 (n=5) received no supplementation and served as the control while group 2 (n=6) and 3 (n=6) received 2ml and 4ml red palm oil (RPO), respectively. Plasma total polyphenols, plasma antioxidant capacity [i. e. oxygen radical absorbance capacity (ORAC)], ferric reducing antioxidant power (FRAP) as well as levels of antioxidant enzymes [catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD)] were determined using established techniques.