Mustapha Umar Imam

Ethyl acetate extract of germinated brown rice attenuates hydrogen peroxide-induced oxidative stress in human SH-SY5Y neuroblastoma cells: role of anti-apoptotic, pro-survival and antioxidant genes

BackgroundThere are reports of improved metabolic outcomes due to consumption of germinated brown rice (GBR). Many of the functional effects of GBR can be linked to its high amounts of antioxidants. Interestingly, dietary components with high antioxidants have shown promise in the prevention of neurodegenerative diseases like Alzheimer’s disease (AD). This effect of dietary components is mostly based on their ability to prevent apoptosis, which is believed to link oxidative damage to pathological changes in AD. In view of the rich antioxidant content of GBR, we studied its potential to modulate processes leading up to AD.MethodsThe total phenolic content and antioxidant capacity of the ethyl acetate extract of GBR were compared to that of brown rice (BR), and the cytotoxicity of both extracts were determined on human SH-SY5Y neuronal cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) Assay. Based on its higher antioxidant potentials, the effect of the GBR extract on morphological changes due to hydrogen peroxide (H2O2)-induced oxidative damage in human SH-SY5Y neuronal cells was examined using inverted light microscope and fluorescence microscope by means of acridine orange-propidium iodide (AO/PI) staining. Also, evaluation of the transcriptional regulation of antioxidant and apoptotic genes was carried out using Multiplex Gene Expression System.ResultsThe ethyl acetate extract of GBR had higher total phenolic content and antioxidant capacity compared to BR. The cytotoxicity results showed that GBR extract did not cause any damage to the human SH-SY5Y neuronal cells at concentrations of up to 20 ppm, and the morphological analyses showed that the GBR extract (up to 10 ppm) prevented H2O2-induced apoptotic changes in the cells. Furthermore, multiplex gene expression analyses showed that the protection of the cells by the GBR extract was linked to its ability to induce transcriptional changes in antioxidant (SOD 1, SOD 2 and catalase) and apoptotic (AKT, NF-Kβ, ERK1/2, JNK, p53 and p38 MAPK) genes that tended towards survival.ConclusionsTaken together, the results of our study showed that the ethyl acetate extract of GBR, with high antioxidant potentials, could prevent H2O2-induced oxidative damage in SH-SY5Y cells. The potential of GBR and its neuroprotective mechanism in ameliorating oxidative stress-related cytotoxicity is therefore worth exploring further.

Antidiabetic Properties of Germinated Brown Rice: A Systematic Review

Diet is an important variable in the course of type 2 diabetes, which has generated interest in dietary options like germinated brown rice (GBR) for effective management of the disease among rice-consuming populations. In vitro data and animal experiments show that GBR has potentials as a functional diet for managing this disease, and short-term clinical studies indicate encouraging results. Mechanisms for antidiabetic effects of GBR due to bioactive compounds like γ-aminobutyric acid (GABA), γ-oryzanol, dietary fibre, phenolics, vitamins, acylated steryl β-glucoside, and minerals include antihyperglycemia, low insulin index, antioxidative effect, antithrombosis, antihypertensive effect, hypocholesterolemia, and neuroprotective effects. The evidence so far suggests that there may be enormous benefits for diabetics in rice-consuming populations if white rice is replaced with GBR. However, long-term clinical studies are still needed to verify these findings on antidiabetic effects of GBR. Thus, we present a review on the antidiabetic properties of GBR from relevant preclinical and clinical studies, in order to provide detailed information on this subject for researchers to review the potential of GBR in combating this disease.

A randomised controlled trial on hypolipidemic effects of Nigella Sativa seeds powder in menopausal women

BackgroundThe risk of cardiovascular diseases (CVD) is increased tremendously among menopausal women, and there is an increasing demand for alternative therapies for managing factors like dyslipidemia that contribute to CVD development.MethodsIn this study, Nigella sativa was evaluated for its hypolipidemic effects among menopausal women. In a randomised trial, hyperlipidemic menopausal women were assigned to treatment (nu2009=u200919) or placebo groups (nu2009=u200918), and given N. sativa or placebo for two months after their informed consents were sought. At baseline, blood samples were taken and at one month intervals thereafter until one month after the end of the study.ResultsThe results showed that N. sativa significantly improved lipid profiles of menopausal women (decreased total cholesterol, low density lipoprotein cholesterol and triglyceride, and increased high density lipoprotein cholesterol) more than the placebo treatment over 2xa0months of intervention. One month after cessation of treatment, the lipid profiles in the N. sativa-treated group tended to change towards the pretreatment levels.ConclusionsN. sativa is thought to have multiple mechanisms of action and is cost-effective. Therefore, it could be used by menopausal women to remedy hypercholesterolemia, with likely more benefits than with single pharmacological agents that may cause side effects. The use of N. sativa as an alternative therapy for hypercholesterolemia could have profound impact on the management of CVD among menopausal women especially in countries where it is readily available.

Induction of apoptosis through oxidative stress-related pathways in MCF-7, human breast cancer cells, by ethyl acetate extract of Dillenia suffruticosa

BackgroundBreast cancer is one of the most dreading types of cancer among women. Herbal medicine has becoming a potential source of treatment for breast cancer. Herbal plant Dillenia suffruticosa (Griff) Martelli under the family Dilleniaceae has been traditionally used to treat cancerous growth. In this study, the anticancer effect of ethyl acetate extract of D. suffruticosa (EADs) was examined on human breast adenocarcinoma cell line MCF-7 and the molecular pathway involved was elucidated.MethodsEADs was obtained from the root of D. suffruticosa by using sequential solvent extraction. Cytotoxicity was determined by using MTT assay, mode of cell death by cell cycle analysis and apoptosis induction by Annexin-FITC/PI assay. Morphology changes in cells were observed under inverted light microscope. Involvement of selected genes in the oxidative stress-mediated signaling pathway was explored using multiplex gene expression analysis.ResultsThe treatment of EADs caused cytotoxicity to MCF-7 cells in a dose- and time-dependent manner at 24, 48 and 72xa0hours with IC50 of 76u2009±u20092.3, 58u2009±u20090.7 and 39u2009±u20093.6xa0μg/mL, respectively. The IC50 of tamoxifen-treated MCF-7 cells was 8u2009±u20090.5xa0μg/mL. Induction of apoptosis by EADs was dose- and time- dependent. EADs induced non-phase specific cell cycle arrest at different concentration and time point. The multiplex mRNA expression study indicated that EADs-induced apoptosis was accompanied by upregulation of the expression of SOD1, SOD2, NF-κB, p53, p38 MAPK, and catalase, but downregulation of Akt1.ConclusionIt is suggested that EADs induced apoptosis in MCF-7 cells by modulating numerous genes which are involved in oxidative stress pathway. Therefore, EADs has the potential to act as an effective intervention against breast cancer cells.

Thymoquinone prevents β-amyloid neurotoxicity in primary cultured cerebellar granule neurons.

AbstractThymoquinone (TQ), a bioactive constituent of Nigella sativa Linn (N. sativa) has demonstrated several neuropharmacological attributes. In the present study, the neuroprotective properties of TQ were investigated by studying its anti-apoptotic potential to diminish β-amyloid peptide 1–40 sequence (Aβ1–40)-induced neuronal cell death in primary cultured cerebellar granule neurons (CGNs). The effects of TQ against Aβ1–40-induced neurotoxicity, morphological damages, DNA condensation, the generation of reactive oxygen species, and caspase-3, -8, and -9 activation were investigated. Pretreatment of CGNs with TQ (0.1 and 1xa0μM) and subsequent exposure to 10xa0μM Aβ1–40 protected the CGNs against the neurotoxic effects of the latter. In addition, the CGNs were better preserved with intact cell bodies, extensive neurite networks, a loss of condensed chromatin and less free radical generation than those exposed to Aβ1–40 alone. TQ pretreatment inhibited Aβ1–40-induced apoptosis of CGNs via both extrinsic and intrinsic caspase pathways. Thus, the findings of this study suggest that TQ may prevent neurotoxicity and Aβ1–40-induced apoptosis. TQ is, therefore, worth studying further for its potential to reduce the risks of developing Alzheimer’s disease.n

Effects of White Rice, Brown Rice and Germinated Brown Rice on Antioxidant Status of Type 2 Diabetic Rats

Oxidative stress is implicated in the pathogenesis of diabetic complications, and can be increased by diet like white rice (WR). Though brown rice (BR) and germinated brown rice (GBR) have high antioxidant potentials as a result of their bioactive compounds, reports of their effects on oxidative stress-related conditions such as type 2 diabetes are lacking. We hypothesized therefore that if BR and GBR were to improve antioxidant status, they would be better for rice consuming populations instead of the commonly consumed WR that is known to promote oxidative stress. This will then provide further reasons why less consumption of WR should be encouraged. We studied the effects of GBR on antioxidant status in type 2 diabetic rats, induced using a high-fat diet and streptozotocin injection, and also evaluated the effects of WR, BR and GBR on catalase and superoxide dismutase genes. As dietary components, BR and GBR improved glycemia and kidney hydroxyl radical scavenging activities, and prevented the deterioration of total antioxidant status in type 2 diabetic rats. Similarly, GBR preserved liver enzymes, as well as serum creatinine. There seem to be evidence that upregulation of superoxide dismutase gene may likely be an underlying mechanism for antioxidant effects of BR and GBR. Our results provide insight into the effects of different rice types on antioxidant status in type 2 diabetes. The results also suggest that WR consumption, contrary to BR and GBR, may worsen antioxidant status that may lead to more damage by free radicals. From the data so far, the antioxidant effects of BR and GBR are worth studying further especially on a long term to determine their effects on development of oxidative stress-related problems, which WR consumption predisposes to.

Neuroprotective Effects of Germinated Brown Rice against Hydrogen Peroxide Induced Cell Death in Human SH-SY5Y Cells

The neuroprotective and antioxidative effects of germinated brown rice (GBR), brown rice (BR) and commercially available γ-aminobutyric acid (GABA) against cell death induced by hydrogen peroxide (H2O2) in human neuroblastoma SH-SY5Y cells have been investigated. Results show that GBR suppressed H2O2-mediated cytotoxicity and induced G0/G1 phase cell cycle arrest in SH-SY5Y cells. Moreover, GBR reduced mitochondrial membrane potential (MMP) and prevented phosphatidylserine (PS) translocation in SH-SY5Y cells, key features of apoptosis, and subsequent cell death. GBR exhibited better neuroprotective and antioxidative activities as compared to BR and GABA. These results indicate that GBR possesses high antioxidative activities and suppressed cell death in SH-SY5Y cells by blocking the cell cycle re-entry and apoptotic mechanisms. Therefore, GBR could be developed as a value added functional food to prevent neurodegenerative diseases caused by oxidative stress and apoptosis.

Induction of cell cycle arrest and apoptosis in caspase-3 deficient MCF-7 cells by Dillenia suffruticosa root extract via multiple signalling pathways

BackgroundDillenia suffruticosa root dichloromethane extract (DCM-DS) has been reported to exhibit strong cytotoxicity towards breast cancer cells. The present study was designed to investigate the cell cycle profile, mode of cell death and signalling pathways of DCM-DS-treated human caspase-3 deficient MCF-7 breast cancer cells.MethodsDillenia suffruticosa root was extracted by sequential solvent extraction. The anti-proliferative activity of DCM-DS was determined by using MTT assay. The mode of cell death was evaluated by using inverted light microscope and Annexin-V/PI-flow cytometry analysis. Cell cycle analysis and measurement of intracellular reactive oxygen species (ROS) were performed by using flow cytometry. MCF-7 cells were co-treated with antioxidants α-tocopherol and ascorbic acid to evaluate whether the cell death was mainly due to oxidative stress. GeXP-based multiplex system was employed to investigate the expression of apoptotic, growth and survival genes in MCF-7 cells. Western blot analysis was performed to confirm the expression of the genes.ResultsDCM-DS was cytotoxic to the MCF-7 cells in a time-and dose-dependent manner. The IC50 values of DCM-DS at 24, 48 and 72xa0hours were 20.3u2009±u20092.8, 17.8u2009±u20091.5 and 15.5u2009±u20090.5xa0μg/mL, respectively. Cell cycle analysis revealed that DCM-DS induced G0/G1 and G2/M phase cell cycle arrest in MCF-7 cells at low concentration (12.5 and 25xa0μg/mL) and high concentration (50xa0μg/mL), respectively. Although Annexin-V/PI-flow cytometry analysis has confirmed that DCM-DS induced apoptosis in MCF-7 cells, the distinct characteristics of apoptosis such as membrane blebbing, chromatin condensation, nuclear fragmentation and formation of apoptotic bodies were not observed under microscope. DCM-DS induced formation of ROS in MCF-7 cells. Nevertheless, co-treatment with antioxidants did not attenuate the cell death at low concentration of DCM-DS. The pro-apoptotic gene JNK was up-regulated whereby anti-apoptotic genes AKT1 and ERK1/2 were down-regulated in a dose-dependent manner. Western blot analysis has confirmed that DCM-DS significantly up-regulated the expression of pro-apoptotic JNK1, pJNK and down-regulated anti-apoptotic AKT1, ERK1 in MCF-7 cells.ConclusionDCM-DS induced cell cycle arrest and apoptosis in MCF-7 cells via multiple signalling pathways. It shows the potential of DCM-DS to be developed to target the cancer cells with mutant caspase-3.

Are bioactive-rich fractions functionally richer?

Abstract Plant bioresources are relied upon as natural, inexpensive, and sustainable remedies for the management of several chronic diseases worldwide. Plants have historically been consumed for medicinal purposes based on traditional belief, but this trend is currently changing. The growing interest in the medicinal properties of plant bioresources stems from concerns of side effects and other adverse effects caused by synthetic drugs. This interest has yielded a better understanding of the roles of plant bioactive compounds in health promotion and disease prevention, including the underlying mechanisms involved in such functional effects. The desire to maximize the potential of phytochemicals has led to the development of “rich fractions,” in which extracts contain bioactive compounds in addition to elevated levels of the primary compound. Although a rich fraction effectively increases the bioactivity of the extract, the standardization and quality assurance process can be challenging. However, the supercritical fluid extraction (SFE) system is a promising green technology in this regard. Future clinical and pharmacological studies are needed to fully elucidate the implications of these preparations in the management of human diseases, thereby fostering a move toward evidence-based medicine.

Mechanistic basis for protection of differentiated SH-SY5Y cells by oryzanol-rich fraction against hydrogen peroxide-induced neurotoxicity

BackgroundApoptosis is often the end result of oxidative damage to neurons. Due to shared pathways between oxidative stress, apoptosis and antioxidant defence systems, an oxidative insult could end up causing cellular apoptosis or survival depending on the severity of the insult and cellular responses. Plant bioresources have received close attention in recent years for their potential role in regulating the pathways involved in apoptosis and oxidative stress in favour of cell survival. Rice bran is a bioactive-rich by-product of rice milling process. It possesses antioxidant properties, making it a promising source of antioxidants that could potentially prevent oxidative stress-induced neurodegenerative diseases.MethodsThus, the present study investigated the neuroprotective properties of oryzanol-rich fraction (ORF) against hydrogen peroxide (H2O2)-induced neurotoxicity in differentiated human neuroblastoma SH-SY5Y cells. ORF was extracted from rice bran using a green technology platform, supercritical fluid extraction system. Furthermore, its effects on cell viability, morphological changes, cell cycle, and apoptosis were evaluated. The underlying transcriptomic changes involved in regulation of oxidative stress, apoptosis and antioxidant defence systems were equally studied.ResultsORF protected differentiated SH-SY5Y cells against H2O2-induced neurotoxicity through preserving the mitochondrial metabolic enzyme activities, thus reducing apoptosis. The mechanistic basis for the neuroprotective effects of ORF included upregulation of antioxidant genes (catalase, SOD 1 and SOD 2), downregulation of pro-apoptotic genes (JNK, TNF, ING3, BAK1, BAX, p21 and caspase-9), and upregulation of anti-apoptotic genes (ERK1/2, AKT1 and NF-Kβ).ConclusionThese findings suggest ORF may be an effective antioxidant that could prevent oxidative stress-induced neurodegenerative disorders.