Effects of modified rice bran on serum lipids and taste preference in streptozotocin-induced diabetic rats

Modified rice bran arabinoxylan as a nutraceutical in health and disease-A scoping review with bibliometric analysis

Rice bran arabinoxylan compound (RBAC) is a polysaccharide modified by Lentinus edodes mycelial enzyme widely used as a nutraceutical. To explore translational research on RBAC, a scoping review was conducted to synthesise research evidence from English (MEDLINE, ProQuest, CENTRAL, Emcare, CINAHL+, Web of Science), Japanese (CiNii, J-Stage), Korean (KCI, RISS, ScienceON), and Chinese (CNKI, Wanfang) sources while combining bibliometrics and network analyses for data visualisation. Searches were conducted between September and October 2022. Ninety-eight articles on RBAC and the biological activities related to human health or disease were included. Research progressed with linear growth (median = 3/year) from 1998 to 2022, predominantly on Biobran MGN-3 (86.73%) and contributed by 289 authors from 100 institutions across 18 countries. Clinical studies constitute 61.1% of recent articles (2018 to 2022). Over 50% of the research was from the USA (29/98, 29.59%) and Japan (22/98, 22.45%). A shifting focus from immuno-cellular activities to human translations over the years was shown via keyword visualisation. Beneficial effects of RBAC include immunomodulation, synergistic anticancer properties, hepatoprotection, antiinflammation, and antioxidation. As an oral supplement taken as an adjuvant during chemoradiotherapy, cancer patients reported reduced side effects and improved quality of life in human studies, indicating RBAC's impact on the psycho-neuro-immune axis. RBAC has been studied in 17 conditions, including cancer, liver diseases, HIV, allergy, chronic fatigue, gastroenteritis, cold/flu, diabetes, and in healthy participants. Further translational research on the impact on patient and community health is required for the evidence-informed use of RBAC in health and disease.

Efficiency of Biobran/MGN-3, an Arabinoxylan Rice Bran, in Attenuating Diabetes-Induced Cognitive Impairment of the Hippocampus via Oxidative Stress and IR/Akt/NF-κB in Rats

Type 2 diabetes mellitus (T2DM) is a common metabolic disease accompanied by cognitive impairment, hippocampal malfunctioning, and inflammation. Biobran/MGN-3, an arabinoxylan rice bran, has been shown to have an antidiabetic effect in streptozotocin-induced diabetic rats. The present study investigates Biobran's effect against diabetes-induced cognitive impairment and synaptotoxicity in the hippocampus via oxidative stress and the IR/A/NF-κB signaling pathway in rats. Diabetes was induced via i.p. injection of streptozotocin (STZ) (40 mg/kg BW); STZ-treated rats were then administered Biobran (100 mg/kg BW) for 4 wks. Biobran supplementation improved motor coordination and muscular strength, as assessed by Kondziella's inverted screen test. Biobran also improved concentration levels of glutathione (GSH), antioxidant enzymes, acetylcholine (ACh), dopamine, serotonin, insulin receptor (IR), and alpha serine-threonine protein kinase (Akt); it protected against elevated levels of glucose, total cholesterol, triglycerides, oxidative stress markers, TBARS, NO, AChE, and MAO; and it significantly decreased inflammatory cytokines levels of IL-1β, NF-κB, TNF-α, and amyloid β_1-42. Moreover, Biobran ameliorated hippocampal histological alterations. Immunohistochemical observations showed that Biobran reduced overexpression of hippocampal synaptophysin and Ki67 relative to untreated diabetic rats. Biobran may ameliorate hippocampal alterations in diabetic rats via its antidiabetic, antiproliferative, anti-inflammatory, antiapoptotic, and antioxidant effects.

The Health-Promoting Properties and Clinical Applications of Rice Bran Arabinoxylan Modified with Shiitake Mushroom Enzyme-A Narrative Review

Rice bran arabinoxylan compound (RBAC) is derived from defatted rice bran hydrolyzed with Lentinus edodes mycelial enzyme. It has been marketed as a functional food and a nutraceutical with health-promoting properties. Some research has demonstrated this rice bran derivative to be a potent immunomodulator, which also possesses anti-inflammatory, antioxidant, and anti-angiogenic properties. To date, research on RBAC has predominantly focused on its immunomodulatory action and application as a complementary therapy for cancer. Nonetheless, the clinical applications of RBAC can extend beyond cancer therapy. This article is a narrative review of the research on the potential benefits of RBAC for cancer and other health conditions based on the available literature. RBAC research has shown it to be useful as a complementary treatment for cancer and human immunodeficiency virus infection. It can positively modulate serum glucose, lipid and protein metabolism in diabetic patients. Additionally, RBAC has been shown to ameliorate irritable bowel syndrome and protect against liver injury caused by hepatitis or nonalcoholic fatty liver disease. It can potentially ease symptoms in chronic fatigue syndrome and prevent the common cold. RBAC is safe to consume and has no known side effects at the typical dosage of 2–3 g/day. Nevertheless, further research in both basic studies and human clinical trials are required to investigate the clinical applications, mechanisms, and effects of RBAC.

Iron-Binding Capacity of Defatted Rice Bran Hydrolysate and Bioavailability of Iron in Caco-2 Cells

The present study was aimed at utilizing defatted rice bran (DRB) protein as an iron-binding peptide to enhance iron uptake in humans. DRB samples were treated with Alcalase and Flavourzyme, and the total extractable peptides were determined. Furthermore, the iron-binding capacities of the DRB protein hydrolysates were determined, whereas iron bioavailability studies were conducted using an in vitro digestion and absorption model (Caco-2 cells). The results showed that the DRB protein hydrolysates produced by combined Alcalase and Flavourzyme hydrolysis had the best iron-binding capacity (83%) after 90 min of hydrolysis. The optimal hydrolysis time to produce the best iron-uptake in Caco-2 cells was found to be 180 min. The results suggested that DRB protein hydrolysates have potent iron-binding capacities and may enhance the bioavailability of iron, hence their suitability for use as iron-fortified supplements.

Improvement of lipid profile by amaranth (Amaranthus esculantus) supplementation in streptozotocin-induced diabetic rats

BACKGROUND/AIMS

Lipid disorders may exacerbate some complications of diabetes. Amaranth has been reported to exhibit a cholesterol-lowering effect in hyperlipidemic animals. The present study was designed to investigate the effect of amaranth on serum glucose and the lipid profile in diabetic rats.

METHODS

Male Sprague-Dawley rats were assigned to normal control, diabetic control, diabetic amaranth-grain (AG)-supplemented (500 g/kg diet) and diabetic amaranth-oil (AO)-supplemented (90 g/kg diet) groups and fed experimental diets for 3 weeks. Effects were monitored on glucose tolerance, serum and liver lipids, and fecal excretions of lipids and bile acids.

RESULTS

Fasting serum glucose levels and the glucose tolerance of diabetic rats were improved by AG and AO supplementation. Serum and liver lipids such as total cholesterol, triglyceride (TG) and very-low-density lipoprotein cholesterol concentrations were also lowered in diabetic animals by AG and AO consumption. Fecal excretions of cholesterol, TG and bile acid were markedly reduced in diabetic rats, and these parameters were dramatically increased by AG and AO supplementation.

CONCLUSION

AG and AO supplementation improve the glucose and lipid metabolism in streptozotocin-induced diabetic rats.

The effect of Malaysian cocoa extract on glucose levels and lipid profiles in diabetic rats

The present study aims to investigate the effect of cocoa extract on serum glucose levels and lipid profiles in streptozotocin-diabetic rats. Cocoa extract (contained 285.6 mg total polyphenol per gram extract) was prepared from fermented and roasted (140 degrees C, 20 min) beans by extracting using 80% ethanol in the ratio of 1-10. The extract of three dosages (1, 2, and 3%) was fed to normal and diabetic rats for a period of 4 weeks. In hyperglycaemic group, cocoa extract (1 and 3%) diets were found to significantly lower (p<0.05) the serum glucose levels compared to the control. Furthermore, supplementation of 1 and 3% cocoa extract had significantly reduced (p<0.05) the level of total cholesterol in diabetic rats. In addition, 1, 2, and 3% cocoa extract diets had significantly lowered (p<0.05) the total triglycerides. Interestingly, this study found that serum HDL-cholesterol had increased significantly (p<0.05) in diabetic rats fed with 2% cocoa extract, while the LDL-cholesterol had decreased significantly (p<0.05) in the 1% treated group. These results indicate that cocoa extract may possess potential hypoglycaemic and hypocholestrolemic effects on serum glucose levels and lipid profiles, respectively. The results also found that the effect of cocoa extract was dose-dependent.

Alternation of hepatic antioxidant enzyme activities and lipid profile in streptozotocin-induced diabetic rats by supplementation of dandelion water extract

BACKGROUND

Dandelion water extract (DWE), an herbal medication, may have an effect on the activity and mRNA expression of hepatic antioxidant enzymes and lipid profile in streptozotocin (STZ)-induced diabetic rats.

METHODS

Male Sprague-Dawley rats were divided into nondiabetic (control), diabetic, and diabetic-DWE-supplemented groups. Diabetes was induced by injecting streptozotocin (55 mg/kg BW, i.p.) in a citrate buffer. The extract was supplemented in 2.4 g of a DWE/kg diet.

RESULTS

The DWE supplement significantly decreased the serum glucose concentration in the diabetic rats. The hepatic superoxide dismutase and catalase activities significantly increased and the GSH-Px activity decreased in the diabetic rats, compared with the control group. When the DWE supplement was given to the diabetic rats, the antioxidant enzyme activity reverted to near-control values. However, there was no difference in the mRNA expression concentrations of these enzymes between the groups. With regard to the hepatic lipid peroxidation product, the malondialdehyde (MDA) content was significantly higher in the diabetic group than in the nondiabetic group. However, the DWE supplement lowered the hepatic MDA concentration in the diabetic-induced rats. The DWE supplement also lowered the total cholesterol and triglyceride concentrations in the serum and hepatic tissue, while increasing the serum HDL-cholesterol in the diabetic rats.

CONCLUSIONS

A DWE supplement can improve the lipid metabolism and is beneficial in preventing diabetic complications from lipid peroxidation and free radicals in diabetic rats.