Supplementation of media with gamma-oryzanol as a novel antioxidant to overcome redox imbalance during bovine oocyte maturation in vitro

This study evaluated the effect of supplementing IVM media with γ-oryzanol (ORY), a nutraceutical derived from rice bran oil, on the development of bovine oocytes and hindering the compromising effect of redox imbalance. An in vitro model of the bovine cumulus-oocyte complex was used for the evaluation of nuclear maturation and development. Antioxidant activity was investigated by assessing the level of ROS (Reactive Oxygen Species) and GSH (glutathione) in oocytes and quantitative changes in gene expression in matured oocytes and their respective cumulus cells. ORY supplementation increased the proportion of MII oocytes, cleaved embryos, and total blastocysts (p < .05) and was linked to higher and lower levels of intracellular GSH and ROS, respectively (p < .05). The treated oocytes and their respective cumulus-granulosa cells showed a modulation in the expression of genes related to apoptosis (downregulation of BAX and CHOP) and oxidative stress (upregulation of NRF2, CAT, and SOD). Also, relative upregulation of OCT-4 and IGF2R in treated oocytes was concomitant with higher subsequent development in terms of cleavage and total blastocyst rates (p < .05). Based on our findings, it appears that ORY supplementation can improve the nuclear maturation and development of bovine oocytes into blastocysts and augment their enzymatic and non-enzymatic antioxidant systems, maintaining the Redox balance and high enzymatic activity against ROS generation.

Organic Rice Production Practices: Effects on Grain End-Use Quality, Healthfulness, and Safety

Demand for rice labeled as organic is growing globally. Consumers state that foods labeled as organic are nutritionally superior and safer than their conventionally produced equivalent. The research question for this systematic review is as follows: is there a difference between the effects of sustainable agriculture and conventional farming methods on rice grain end-use quality, healthfulness, and safety? The studies (n = 23) examined for this review suggest that organic production practices don't influence most end-use quality (e.g., chalk, milling yield, pasting properties) and healthfulness (e.g., gamma-oryzanol fraction and tocols) traits studied, or if it does, it will be to a small degree. If differences in end-use quality traits are found, they will be associated with grain protein content, which varies along with the dose of nitrogen applied during rice growth. We conclude that the studies evaluated in this review found that organically produced rice grain was less likely to contain residues of the pesticides (e.g., organochlorine) examined in the study than the rice is grown using conventional methods. There was some evidence that organically grown rice is more likely to be contaminated with mycotoxin-producing fungi and some mycotoxins. Common shortcomings of the studies were that they were poorly designed, with limited to no details of the cultural management practices used to grow the rice studied, the length of time fields was under organic management not stated, cultivars were not named, and the data wasn't analyzed statistically.

Production of rice bran oil (Oryza sativa L.) microparticles by spray drying taking advantage of the technological properties of cereal co-products

AIM

To evaluate the effects of the use of rice co-products (flour and protein) on the encapsulation process and on the stability of rice bran oil.

METHODS

The stability of the emulsions was evaluated by dynamic turbidimetry, zeta potential, and creaming index. Efficiency parameters, particle size, and densities were investigated in the particles. The study of oxidative stability was carried out by the determination of peroxides and volatiles (60 °C for 8 weeks).

RESULTS

Rice bran oil presented 1.75% ɣ-oryzanol. AG/RP (10% of rice protein): no phase separation after 24 h, higher zeta potential (- 29.09 mV ±0.67), encapsulation efficiency (73.90% ± 0.22) and real density (1.27 g/cm^-3), and smaller particle size (8.27 µm ± 0.13). Lower peroxide (AG/RF/RP) and hexanal (AG/RF) levels were associated with the use of rice flour.

CONCLUSION

The co-products improve the emulsion characteristics, particle properties and stability of the encapsulated oil.

Rice Bran Stabilisation and Oil Extraction Using the Microwave-Assisted Method and Its Effects on GABA and Gamma-Oryzanol Compounds

Rice bran oil (RBO) is a valuable ingredient extracted from rice bran (RB), a side stream of polishing rice grain in the milling process. RBO is rich in bioactive ingredients with potential health benefits, such as gamma-oryzanol (GO) and gamma-aminobutyric acid (GABA). Despite its benefits, the quality of RBO depends on the degree of stabilisation of the RB, which is easily affected by lipase enzymes, and thus needs an effective treatment prior to RBO production. To assess the potential of the microwave-assisted method for RB stabilisation and RBO extraction, three Carolino rice varieties (Ariete, Teti, Luna) were tested. The effect of RB stabilisation was evaluated via acid value, water absorption, and GO and GABA levels. The RBO yield was optimised by solvent, temperature, and solvent-to-sample ratio, and the GO and fatty acid levels were determined. The RB stabilisation for the Luna variety did not affect the GO and GABA; for the Ariete and Teti varieties, the GO decreased by 34.4% and 24.2%, and the GABA increased by 26.5% and 47.0%, respectively. The GO levels in RBO samples were not affected by RB stabilisation. The RBO nutritional value was confirmed by the suitable ratio (>2) between polyunsaturated (PUFA) and saturated fatty acids (SFA), with the Teti variety presenting the highest ratio.

Gamma-oryzanol protects human liver cell (L02) from hydrogen peroxide-induced oxidative damage through regulation of the MAPK/Nrf2 signaling pathways

Gamma-oryzanol (Orz), a mixture of the ferulic acid ester of triterpene alcohols and phytosterols, was found abundantly in rice bran and rice bran oil which could be available and served as an antioxidant. The present study was to explore the potential protective effects of Orz on oxidative stress and cell apoptosis in human hepatic cells (L02 cells) induced by hydrogen peroxide (H₂ O₂ ). Flow cytometry detection and Hoechst 33258 staining showed that Orz significantly restored cell cycle and ameliorated apoptosis in H₂ O₂ -challenged L02 cells. Orz pretreatment inhibited H₂ O₂ -induced cell apoptosis by increasing the scavenging of hydroxyl radicals (OH·), and efficiently decreasing the production of nitric oxide (NO). Moreover, a loss of total antioxidant capacity (T-AOC) and adenosine triphosphatase (ATPase) were enhanced in H₂ O₂ -mediated L02 cells pretreated with Orz. Furthermore, preincubation with Orz reduced H₂ O₂ -mediated the proapoptotic protein of Bak expression and the phosphorylation of ASK1, p38, JNK, and ERK, and increased the anti-apoptotic protein of Bcl-xl expression and anti-oxidative stress proteins of Nrf2 and HO-1 expression. The findings suggested that Orz exerts the cytoprotective effects in H₂ O₂ -induced L02 cells apoptosis by ameliorating oxidative stress via inhibiting MAPK signaling pathway and activating Nrf2 signaling pathway. PRACTICAL APPLICATIONS: Gamma-oryzanol (Orz), a mixture of the ferulic acid ester of triterpene alcohols and phytosterols, was found abundantly in rice bran and rice bran oil which could be availably served as an antioxidant. In this study, it was found that Orz exerts the cytoprotective effects in H₂ O₂ -induced L02 cell apoptosis by ameliorating oxidative stress via the inhibition of MAPK signaling pathway and the activation of Nrf2 signaling pathway, which provides a theoretical basis for dietary adding natural products to prevent or treat oxidative stress-related diseases.

Biological Functions and Activities of Rice Bran as a Functional Ingredient: A Review

Rice bran (RB) is a nutrient-rich by-product of the rice milling process. It consists of pericarp, seed coat, nucellus, and aleurone layer. RB is a rich source of a protein, fat, dietary fibers, vitamins, minerals, and phytochemicals (mainly oryzanols and tocopherols), and is currently mostly used as animal feed. Various studies have revealed the beneficial health effects of RB, which result from its functional components including dietary fiber, rice bran protein, and gamma-oryzanol. The health effects of RB including antidiabetic, lipid-lowering, hypotensive, antioxidant, and anti-inflammatory effects, while its consumption also improves bowel function. These health benefits have drawn increasing attention to RB in food applications and as a nutraceutical product to mitigate metabolic risk factors in humans. This review therefore focuses on RB and its health benefits.

Comparing the effect of rooster semen extender supplemented with gamma-oryzanol and its nano form on post-thaw sperm quality and fertility

Antioxidant nanoparticles include the potential for improving sperm cryopreservation. The aim of performing this study was to evaluate the effects of gamma-oryzanol (GO) at 0 (C) (control group), 20 (GO20), 40 (GO40), 60 (GO60), 80 (GO80), and 100 (GO100) µM and gamma-oryzanol nanoparticles (GON) at 0 (CN), 20 (GON20), 40 (GON40), 60 (GO60), 80 (GON80), and 100 (GON100) µM on post-thawed sperm quality and fertility of rooster sperm. Sperm motility, plasma membrane integrity, total abnormality, mitochondrial activity (Rhodamine 123), apoptotic features (Annexin V/Propidium iodide), reactive oxygen species (ROS) production, ATP content and the fertility and hatchability were evaluated after thawing. Total motility in GON60 and GON80 were significantly higher compared to control groups (C and CN). GON80 showed the greatest percentages of progressive motilities. When GO80, GON60, and GON80 were added to the cryopreservation medium, the plasma membrane functionality of the semen samples improved. The minimum abnormality of spermatozoa is observed in the group treated with GON80. The groups treated with GON60 and GON80 had greater (P < 0.05) mitochondrial activity. The level of sperm ROS after cryopreservation was significantly lower in GON60 and GON80 groups. Live sperm was significantly higher (P < 0.05) in GON60 and GON80 group compared to other groups. GON60 and GON80 groups also led to the lowest significant percentage of apoptosis-like change sperm. Greater fertility percentages were observed (P < 0.05) when sperm were stored in extenders treated with GON60 and GON80. GON80 resulted in significantly improved hatched eggs compared to C, GO60, GO180 and CN. In conclusion, supplementation of Lake extender with 60 and 80 µM gamma-oryzanol nanoparticles could be a proper process to improve freeze-thawing rooster sperm quality leading to better freeze/thaw characteristics.

Simultaneous miRNA and mRNA Transcriptome Profiling of Differentiating Equine Satellite Cells Treated with Gamma-Oryzanol and Exposed to Hydrogen Peroxide

Gamma-oryzanol (GO) is a popular supplement for performance horses, dogs, and humans. Previous studies indicated that GO supplementation decreases creatine kinase activity and lactate level after exercise and may affect oxidative stress in Thoroughbred horses. GO may change genes expression in equine satellite cells (ESC). The purpose of this study was to evaluate the effect of GO on miRNA, gene expression, oxidative stress, and cell damage and viability in differentiating ESC pretreated with hydrogen peroxide (H₂O₂). ESCs were obtained from a young horse’s skeletal muscle. ESCs were pre-incubated with GO (24 h) and then exposed to H₂O₂ for one hour. For the microRNA and gene expression assessment, the microarray technique was used. Identified miRNAs and genes were validated using real time-quantitative polymerase chain reaction. Several tests related to cell viability, cell damage, and oxidative stress were performed. The microarray analysis revealed differences in 17 miRNAs and 202 genes between GO-treated and control ESC. The tests related to apoptosis, cell viability, and oxidative stress showed that GO affects these processes to varying degrees. Our results suggest that GO can change miRNA and gene expression and may impact the processes involved in tissue repairing after an injury.

Potential Gastroprotective Activity of Rice Bran (Oryza sativa L.) Extracted by Ionic Liquid-Microwave-Assisted Extraction against Ethanol-Induced Acute Gastric Ulcers in Rat Model

The presence of gamma-oryzanol in rice bran oil can be 10⁻20-fold higher than tocopherol and tocotrienol. Gamma-oryzanol has various pharmacological properties. The objective of this study was to evaluate the effectiveness of rice bran extract as a gastroprotective in reducing lesions in ethanol-induced acute gastric ulcer models in rat, using the ionic liquid-microwave-assisted extraction (IL-MAE) method. Rice bran extract was obtained using the IL-MAE method with ionic liquid (IL), 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM]BF₄ (concentration 0.7 M), and a ratio of solid/liquid of 15 g/mL, 15 min extraction time, and 10% microwave power. The rats were pretreated with rice bran extract at different doses (100, 200, and 400 mg/kg body weight; BW) for seven days and subsequently exposed to acute gastric lesions induced by 80% ethanol. Omeprazole (36 mg/kg BW) was used as a standard anti-ulcer drug. The ulcer index, gastric juice acidity, and mucus levels were measured to assess the degree of gastroprotection. The results showed that the oral administration of rice bran extract at a dose of 400 mg/kg BW significantly inhibited the development of ulcer formation by 66.75% and reduced gastric acid levels. Moreover, gamma oryzanol and omeprazole protected the gastric mucosa from ethanol-induced gastric lesions by increasing the level of gastric mucus. Rice bran extract is effective as a gastroprotective therapy sourced from natural ingredients in treating the incidence of gastric ulcers. Most likely, this is related to gamma oryzanol as a bioactive compound contained in rice bran (Oryza sativa L.).

Chitosan Nanoparticles of Gamma-Oryzanol: Formulation, Optimization, and In vivo Evaluation of Anti-hyperlipidemic Activity

The elevated blood levels of cholesterol and low-density lipoproteins result in hyperlipidemia. The available expensive prophylactic treatments are kindred with severe side effects. Therefore, we fabricated the polymeric nanoparticles of gamma-oryzanol to achieving the improved efficacy of drug. The nanoparticles were prepared by ionic gelation method and optimized using 2³ full factorial design taking drug/polymer ratio (X₁), polymer/cross linking agent ratio (X₂), and stirring speed (X₃) as independent variables. The average particle size, percentage entrapment efficiency, and in vitro drug release at 2, 12, and 24 h were selected as response parameters. The factorial batches were statistically analyzed and optimized. The optimized nanoparticles were characterized with respect to particle size (141 nm) and zeta potential (+ 6.45 mV). Results obtained with the prepared and characterized formulation showed 83% mucoadhesion towards the intestinal mucosa. The in vitro findings were complemented well by in vivo anti-hyperlipidemic activity of developed formulation carried out in Swiss albino mouse model. The in vivo studies showed improved atherogenic index, malondialdehyde, and superoxide dismutase levels in poloxamer-407-induced hyperlipidemic animals when treated with oryzanol and gamma-oryzanol nanoformulation. Based on our findings, we believe that chitosan-mediated delivery of gamma-oryzanol nanoparticles might prove better in terms of anti-hyperlipidemic therapeutics.

Effect of Gamma-Oryzanol as Therapeutic Agent to Prevent Cardiorenal Metabolic Syndrome in Animals Submitted to High Sugar-Fat Diet

BACKGROUND

The high consumption of fat and sugar contributes to the development of obesity and co-morbidities, such as diabetes, and cardiovascular and kidney diseases. Different strategies have been used to prevent these diseases associated with obesity, such as changes in eating habits and/or the addition of dietary components with anti-inflammatory and anti-oxidant properties, such as gamma-oryzanol (γOz) present mainly in bran layers and rice germ.

METHODS

Animals were randomly divided into four experimental groups and fed ad libitum for 20 weeks with control diet (C, n = 8), control diet + γOz (C + γOz, n = 8), high-sugar and high-fat diet (HSF, n = 8), and high-sugar and high-fat diet + γOz (HSF + γOz, n = 8). HSF groups also received water + sucrose (25%). The dose of γOz was added to diets to reach 0.5% of final concentration (w/w). Evaluation in animals included food and caloric intake, body weight, plasma glucose, insulin, triglycerides, uric acid, HOMA-IR, glomerular filtration rate, protein/creatinine ratio, systolic blood pressure, and Doppler echocardiographic.

RESULTS

Animals that consumed the HSF diet had weight gain compared to group C, increased insulin, HOMA, glucose and triglycerides, there were also atrial and ventricular structural alterations, deterioration of systolic and diastolic function, decreased glomerular filtration rate, and proteinuria. Gamma-oryzanol is significantly protective against effects on body weight, hypertriglyceridemia, renal damage, and against structural and functional alteration of the heart.

CONCLUSION

Gamma-oryzanol shows potential as a therapeutic to prevent Cardiorenal Metabolic Syndrome.