Blended extract of oat, sorghum, adzuki bean, finger millet, and proso millet improved hyperglycemia and insulin resistance in the streptozotocin-nicotinamide-induced diabetic rats.

Grains contain bioactive components that potentially have protective effects on chronic diseases such as diabetes. The anti-diabetic effects of blended grain ethanol extract (BGE) were evaluated in streptozotocin-nicotinamide (STZ-NA)-induced diabetic rats. BGE was prepared by mixing oat, sorghum, adzuki bean, finger millet, and proso millet (30:30:15:15:10). The rats were assigned into four groups, normal control, diabetic model control (DM), STZ-NA rats administered 200 mg/kg body weight (bw) of metformin, and STZ-NA rats administered 500 mg/kg bw of BGE (BGE). After 6 weeks of administration, the homeostatic model assessment of insulin resistance (12%) in BGE decreased compared to DM. Strikingly, the fasting blood glucose (23%) and oral glucose tolerance test (15%) were improved in BGE compared to DM. BGE also increased insulin immunoreactivities in pancreatic ß-cells. In sum, BGE exhibits anti-hyperglycemic effects by improving fasting glucose levels and insulin secretion from pancreatic ß-cells in the STZ-NA-induced diabetic rats.

Black and Yellow Soybean Consumption Prevents High-Fat Diet-Induced Obesity by Regulating Lipid Metabolism in C57BL/6 Mice.

To evaluate the antiobesity effects of yellow and black soybean, C57BL/6 mice were provided with a normal diet, high-fat diet, HFD-containing yellow soybean powder (YS), and black soybean powder (BS) for six weeks. Compared with the HFD group, both YS and BS decreased body weight by 30.1% and 37.2% and fat in tissue by 33.3% and 55.8%, respectively. Simultaneously, both soybeans significantly reduced the serum triglyceride and total cholesterol levels and regulated the lipogenic mRNA expressions of Pparγ, Acc, and Fas genes in the liver, supporting reduced body adiposity. Furthermore, BS significantly increased Pgc-1α and Ucp1 mRNA expression levels in epididymal adipose tissue, indicating thermogenesis is the key mechanism of BS. Taken together, our findings suggest that both soybeans prevent high-fat diet-induced obesity in mice by regulating lipid metabolism, and BS, in particular, has a greater antiobesity potential than YS.

Comparison of physicochemical properties of sorghum extract by ethanol concentration and its anti-adipogenic effect in 3T3-L1 cells.

Sorghum is a vital cereal source that has various phenolic compounds and potential health-promoting benefits. This study evaluated the phenolic content, antioxidant and anti-obesity effects of sorghum extract (SE) prepared using three solvent systems: 50% (SE50), 80% (SE80), and 100% (SE100) ethanol. The results showed that SE50 exhibited the highest total polyphenol and flavonoid content among the sorghum extracts using different ethanol concentrations as extraction solvents. In addition, SE50 showed significantly higher antioxidant capacity than the other extracts. Interestingly, SE50 significantly inhibited lipid accumulation in 3T3-L1 adipocytes; however, SE80 and SE100 had no beneficial effects. Moreover, SE50 significantly downregulated the mRNA expression levels of adipogenic genes (Cebpα, Pparγ, and Fabp4) and lipogenic genes (Srebp1c, Fas, and Scd1). These results suggest that SE50 is superior to other ethanol extracts in phenolic contents, antioxidant and anti-obesity activities, and it could be used as a nutraceutical for anti-obesity.

Comparison of the effects of commercial whey protein and native whey protein on muscle strength and muscle protein synthesis in rats.

Commercial whey protein (CWP) is generally produced in the cheese making process with heat treatment. Recently, native whey protein (NWP) can be obtained through microfiltration without heat treatment. The difference in physicochemical properties of CWP and NWP was confirmed in previous studies; however, in vivo research on the effect on muscle strength and protein synthesis is still lacking. In this study, rats were orally administered 1.56 g protein/kg body weight of lyophilized beverages containing CWP and NWP for 8 weeks. The biological value and net protein utilization in the NWP were significantly higher than in the CWP. Moreover, NWP increased muscle mass and grip strength compared to CWP. NWP also increased the phosphorylation of the mammalian target of rapamycin and ribosomal protein S6 kinase, pivotal proteins for muscle protein synthesis. These results suggest that NWP enhance muscle strength and protein synthesis more effectively than CWP.

Erratum to: Effect of Modified Casein to Whey Protein Ratio on Dispersion Stability, Protein Quality and Body Composition in Rats.

[This corrects the article DOI: 10.5851/kosfa.2021.e42.].

Encapsulation of resveratrol within size-controlled nanoliposomes: Impact on solubility, stability, cellular permeability, and oral bioavailability.

This study examined the influence of the nanoliposomes (LPs) particle size on the solubility, antioxidant stability, in vitro release profile, Caco-2 cellular transport activity, cellular antioxidant activity, and in vivo oral bioavailability of resveratrol (RSV). LPs with sizes of 300, 150, and 75 nm were prepared using the thin-lipid film hydration method, followed by ultrasonication for 0, 2, and 10 min, respectively. Formulating small LPs (< 100 nm) was effective to enhance the solubility, in vitro release profile, cellular permeability, and cellular antioxidant activity of RSV. A similar pattern was observed for in vivo oral bioavailability. However, the size reduction of RSV-loaded LPs did not promote the antioxidant stability of RSV, owing to their large surface area used to interact with harsh environments. This study provides the better understanding of the appropriate particle size range of LPs to improve their in vitro and in vivo performances of RSV as an effective carrier for oral administration.

Whey Proteins-Fortified Milk with Adjusted Casein to Whey Proteins Ratio Improved Muscle Strength and Endurance Exercise Capacity without Lean Mass Accretion in Rats.

This study investigated the effects of the casein to whey proteins (CW) ratio in milk on body composition, muscle strength, and endurance exercise capacity in rats. Thirty rats were assigned into five groups, and each treatment was administered for eight weeks: (1) control (isocaloric lactose supplementation), (2) CW8:2 (regular milk), (3) CW6:4, (4) CW5:5, and (5) nitrogen-free (lactose). The milk concentration was converted from a human equivalent dose (400 mL/60 kg body weight/day). All the milk-administered groups showed significantly greater growth performance, including body weight and weight gain compared to the isocaloric lactose control (p < 0.05). However, different CW ratios in milk had no effect on growth performance. Additionally, body composition, i.e., lean body mass and adiposity, was not affected by the CW ratio. Interestingly, CW6:4 and CW5:5 had significantly higher plasma branched-chain amino acids concentrations than control and CW8:2 (p < 0.05). In addition, CW5:5 showed significantly increased grip strength by 12-24% and time to exhaustion by 8-62% compared to the other groups (p < 0.05), indicating that the higher whey proteins ratio improved physical performance. We concluded that whey proteins-fortified milk enhances muscle strength and endurance exercise capacity without altering lean mass in rats.

Finger Millet Ethanol Extracts Prevent Hypertension by Inhibiting the Angiotensin-Converting Enzyme Level and Enhancing the Antioxidant Capacity in Spontaneously Hypertensive Rats.

Finger millet (Eleusine coracana) contains high levels of calcium and polyphenols, which have a variety of beneficial functions. We tested the hypothesis that finger millet ethanol extracts (FEs) have an antihypertensive effect in spontaneously hypertensive rats (SHRs). The study groups were assigned as follows: (1) Wistar Kyoto rats (normal); (2) SHRs treated with saline (negative control); (3) SHRs treated with captopril 50 mg/kg bw (positive control); (4) SHRs treated with FE 250 mg/kg bw (FE250); and (5) SHRs treated with FE 500 mg/kg bw (FE500). FE supplementation improved the lipid profiles, including the triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels, without deterioration in liver function. The thiobarbituric acid reactive substance concentration and superoxide dismutase activity significantly improved after the application of FE250 and FE500. Interestingly, FE250 and FE500 application dramatically reduced the systolic blood pressure. FE supplementation exhibited powerful control over the renin-angiotensin system by reducing the angiotensin-converting enzyme levels and renin mRNA expression in the kidney. Additionally, FE500 application ameliorated vascular remodeling, reversed the thickening media, and decreased the media thickness/lumen diameter ratio of the aorta. These results imply that FEs are a potent antihypertensive nutraceutical for regulating the renin-angiotensin system and simultaneously inhibiting oxidative stress.

Effect of Modified Casein to Whey Protein Ratio on Dispersion Stability, Protein Quality and Body Composition in Rats.

The present study was designed to investigate the effects of protein formula with different casein (C) to whey protein (W) ratios on dispersion stability, protein quality and body composition in rats. Modification of the casein to whey protein (CW) ratio affected the extent of protein aggregation, and heated CW-2:8 showed a significantly increased larger particle (>100 µm) size distribution. The largest protein aggregates were formed by whey protein self-aggregation. There were no significant differences in protein aggregation when the CW ratios changed from 10:0 to 5:5. Based on the protein quality assessment (CW-10:0, CW-8:2, CW-5:5, and CW-2:8) for four weeks, CW-10:0 showed a significantly higher feed intake (p<0.05), but the high proportion of whey protein in the diet (CW-5:5 and CW-2:8) increased the feed efficiency ratio, protein efficiency ratio, and net protein ratio compared to other groups. Similarly, CW-2:8 showed greater true digestibility compared to other groups. No significant differences in fat mass and lean mass analyzed by dual-energy x-ray absorptiometry were observed. A significant difference was found in the bone mineral density between the CW-10:0 and CW-2:8 groups (p<0.05), but no difference was observed among the other groups. Based on the results, CW-5:5 improved protein quality without causing protein instability problems in the dispersion.

Black Soybean and Adzuki Bean Extracts Lower Blood Pressure by Modulating the Renin-Angiotensin System in Spontaneously Hypertensive Rats.

Hypertension, causing cardiovascular disease, stroke, and heart failure, has been a rising health issue worldwide. Black soybeans and adzuki beans have been widely consumed throughout history due to various bioactive components. We evaluated the antihypertensive effects of black soybean and adzuki bean ethanol extracts on blood pressure, renin-angiotensin system (RAS), and aortic lesion in spontaneously hypertensive rats. A group of WKY (normal) and six groups of spontaneously hypertensive rats were administered with saline (SHR), 50 mg/kg of captopril (CAP), 250 and 500 mg/kg of black soybean extracts (BE250 and BE500), 250 and 500 mg/kg of adzuki bean extracts (AE250 and AE500) for eight weeks. BE250, BE500, AE250, and AE500 significantly (p < 0.05) reduced relative liver weight, AST, ALT, triglyceride, total cholesterol, systolic blood pressure, and angiotensin-converting-enzyme level compared to SHR. The angiotensin II level in AE500 and renin mRNA expression in BE500 and AE500 were significantly (p < 0.05) decreased compared to SHR. The lumen diameter was significantly (p < 0.05) reduced in only CAP. Furthermore, systolic and diastolic blood pressure and angiotensin II level in AE500 were lower than those of BE500. These results suggest that AE exhibit more antihypertensive potential than BE in spontaneously hypertensive rats.