Oral toxicological studies of black soybean (Glycine max) hull extract: acute studies in rats and mice, and chronic studies in mice

Safety Assessment of Soy-Derived Ingredients as Used in Cosmetics

The Expert Panel for Cosmetic Ingredient Safety (Panel) reviewed the safety of 28 soy-derived ingredients as used in cosmetic products. These ingredients are reported to primarily function as antioxidants, skin protectants, skin-conditioning agents, and hair-conditioning agents. The Panel considered the available data relating to the safety of these ingredients in cosmetic formulations, and concluded that 24 of the 28 soy-derived ingredients are safe in cosmetics in the present practices of use and concentration described in this safety assessment. The Panel also concluded that the available data are insufficient to make a determination that Glycine Max (Soybean) Callus Culture, Glycine Max (Soybean) Callus Culture Extract, Glycine Max (Soybean) Callus Extract, and Glycine Max (Soybean) Phytoplacenta Conditioned Media are safe under the intended conditions of use in cosmetic formulations.

Black soybean seed coat polyphenols have different effects on glucose and lipid metabolism in growing and young adult mice

Black soybean contains flavan-3-ols and cyanidin 3-O-glucoside in its seed coat. Polyphenol-rich black soybean seed coat extract (BE) possesses various health benefits, such as antioxidant, anti-obesity, and anti-hyperglycemic effects. However, these functions have been evaluated mainly in the growing stage of animals, and there is no comparison data for different life stages. In this present study, we compared the effect of BE in growing (5-week old) and young adult (22-week old) ICR male mice. These mice were given an AIN 93M diet containing 2.0% BE for 4 weeks. BE did not affect body weight gain in both growing and young adult mice, but it suppressed mesenteric and subcutaneous white adipose tissue weights and decreased the cell size. BE also significantly suppressed plasma free-fatty acid levels. The effect of both BE and life stages were observed in the protein expression of adipogenesis-related transcription factors; in particular, BE suppressed the expression of C/EBPα and PPARγ. No significant change was observed in lipolysis and lipogenesis factors in the white adipose tissue and liver. Alternatively, BE showed low glucose tolerance without affecting plasma insulin levels after glucose loading in young adult mice, as seen from the results of the oral glucose tolerance test. However, plasma glucose and insulin levels remained unchanged at the end of the experimental period. In conclusion, these results strongly suggest that the health-beneficial effects of BE may alter in mice at different life stages.

A flavonoid-rich Smilax china L. extract prevents obesity by upregulating the adiponectin-receptor/AMPK signalling pathway and modulating the gut microbiota in mice

The aim of this study was to investigate the effects of Smilax china L. flavonoid (SCF) on obesity and changes in gut microbiota high-fat/high-sucrose (HFHS)-fed mice. Male C57BL/6 mice fed either a normal-chow (NC) or a HFHS diet were treated with SCF for 12 weeks. The effect of SCF on the composition of gut microbiota was assessed by 16S rDNA sequencing. SCFA levels in the caecum were quantified by GC-MS. SCF supplementation alleviated the body weight gain, fat accumulation, serum lipid parameters, and hepatic steatosis and improved glucose homeostasis. SCF significantly increased plasma adiponectin level, adiponectin-receptor-gene (AdipoR1 and AdipoR2) expression in the liver, activated AMPKα, downregulated the expression of SREBP1-c, FAS, and ACCα, and upregulated the expression of PPARα, CPT-1α, and UCP-1. The anti-obesity effects of SCF might be through upregulation of adiponectin-receptor/AMPK signalling to improve lipid metabolism. SCF reversed HFHS-induced dysbiosis of gut microbiota and decreased SCFA production in the caecum, thus reducing energy absorption and leading to loss of body weight. Spearman's correlation analysis revealed significant correlations between obesity phenotypes, SCFA levels, and changes in gut microbiota. The results showed that SCF may be an effective dietary supplement that is useful for suppressing the development of obesity and associated disorders.

Inhibitory effects of cyanidin-3-O-glucoside in black soybean hull extract on RBL-2H3 cells degranulation and passive cutaneous anaphylaxis reaction in mice

Black soybean hull extract (BSHE) exhibits a variety of biological activities. However, little is known about the effects of BSHE on immunoglobulin E (IgE)-mediated type I allergic reactions. The anti-allergic effect of BSHE was assessed with the degranulation assay using rat basophilic leukemia RBL-2H3 cells and the passive cutaneous anaphylaxis (PCA) reaction in mice. An active compound in BSHE was identified by ultra-performance liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry analysis. BSHE inhibited the release of β-hexosaminidase and histamine in RBL-2H3 cells, and cyanidin-3-O-glucoside (C3G) was identified as one of its active compounds. Oral administering of 200 μmol/kg of C3G to IgE-sensitized mice prior to antigen injection suppressed the PCA reaction, as compared with control (p < 0.01). Intravenous administration of BSHE (C3G content, 5.4%) more strongly inhibited PCA responses at lower doses (100 mg/kg, p < 0.01) than oral administration (1,000 mg/kg, p = 0.059). Intravenous C3G also suppressed PCA response at a low dose (40 mg/kg, p < 0.05), showing the same trend as BSHE. This information can be useful to design appropriate formulations of anthocyanin-based drug products to suppress allergic reactions. This study provides evidence for the potential use of BSHE and C3G for the prevention or the treatment of type I allergies.

Insights into the potential benefits of black soybean (Glycine max L.) polyphenols in lifestyle diseases

Black soybean (Glycine max L.), a cultivar containing abundant polyphenols in its seed coat such as anthocyanins and flavan-3-ols, has been reported to possess various health benefits toward lifestyle diseases. In this review article, the safety evaluation of polyphenol-rich black soybean seed coat extract (BE) and absorption of BE polyphenols are summarized. Additionally, we describe the antioxidant activity of BE polyphenols and their ability to induce antioxidant enzymes. The health benefits of BE and its polyphenols, such as anti-obesity and anti-hyperglycemic activities through the activation of AMP-activated protein kinase and translocation of glucose transporter 4, respectively, are also discussed. Furthermore, we found that black soybean polyphenols were involved in the improvement of vascular function. These emerging data require further investigation in scientific studies and human trials to evaluate the prevention of lifestyle diseases using black soybean polyphenols.

A medicinal and edible formula YH0618 ameliorates the toxicity induced by Doxorubicin via regulating the expression of Bax/Bcl-2 and FOXO4

Chemotherapy is the most common and powerful cancer treatment. Although the nasty side effects seriously influence the clinical practice, no better ways can displace it. Therefore, searching for safe and effective strategies designed to ameliorate chemotherapy-induced toxicity has become an urgent issue in cancer research area. In clinical, a medicinal and edible formula YH0618 showed the effects of reducing the DOX-induced toxicity, especially improving alopecia, nail discoloration, skin hyperpigmentation and fatigue. This study was to investigate the role and mechanism of YH0618 in ameliorating DOX-induced toxicity by in vitro and in vivo experiments. YH0618 selectively attenuated DOX-induced growth inhibition and apoptosis in human normal liver L02 cells and kidney HEK-293 cells, and simultaneously potentiated the anti-cancer effect of DOX in breast cancer MCF-7 and MDA-MB-231 cells by apoptosis pathways. Western blotting results revealed that YH0618 attenuated DOX-induced apoptosis in normal liver and kidney cells through FOXO4-mediated mitochondria-dependent mechanism. Animal experiments demonstrated that, YH0618 did not interfere in DOX-induced reduction in tumor volume and significantly improved DOX-induced hair loss and the increase of alanine aminotransferase (ALT). Histological characteristics showed that YH0618 attenuated DOX-induced heart, liver and kidney damage. The study may shed light on the potential application of YH0618 as a novel medicinal food against chemotherapy-induced toxicity.

Black soybean extract reduces fatty acid contents in subcutaneous, but not in visceral adipose triglyceride in high-fat fed rats

It is known that black soybean (BS) extract, rich in polyphenols, has beneficial effects against obesity, inflammation and insulin resistance. However, detailed effects of BS on lipid metabolism have not been documented well. In the present study, we compared fatty acid composition in visceral and subcutaneous adipose tissues of high-fat fed (HFF) rats and BS administered HFF rats. Black soybean administration for 6 weeks influenced neither body nor adipose tissue weights, blood glucose, plasma insulin levels, or insulin sensitivity. However, BS reduced several saturated (C14:0 and C16:0), monounsaturated (C14:1n-5 and C18:1n-9) and n-6 polyunsaturated (C18:2n-6, C20:3n-6, C20:4n-6 and C22:4n-6) fatty acid contents in subcutaneous fat without any change in n-3 polyunsaturated fatty acid contents. No such effect was observed in fatty acid composition in visceral fat. Long-chain fatty acids are involved in regulation of inflammation. Therefore, those reduced fatty acids may be linked to the effects on suppressing inflammation.

Anthocyanins from the seed coat of black soybean reduce retinal degeneration induced by N-methyl-N-nitrosourea

Anthocyanins are known to have antioxidant effects and thus may play an important role in preventing various degenerative diseases. In this study, we examined the effect of anthocyanins extracted from the seed coat of black soybean on an animal model of retinal degeneration (RD), a leading cause of photoreceptor cell death resulting in blindness. RD was induced in rats by an intraperitoneal injection of N-methyl-N-nitrosourea (MNU) (50mg/kg), a DNA-methylating agent that causes photoreceptor damage. Anthocyanins extracted from black soybean seed coat (50mg/kg) were daily administered, orally, for 1, 2, and 4 weeks after MNU injection. Electroretinographic (ERG) recordings and morphological analyses were performed. In control rats with MNU-induced retinal damage, the ERG recordings showed a gradual significant time-dependent reduction in both a- and b-wave amplitudes compared with those of normal animals. In the MNU-induced RD rats given anthocyanins for 4 weeks, ERG responses were significantly increased compared with untreated RD rats, more apparently in scotopic stimulation than in the photopic condition. However, in the MNU-injected rats given anthocyanins for 1 and 2 weeks, the increase in ERG responses was not significant. Morphologically, the outer nuclear layer, where photoreceptors reside, was well preserved in the anthocyanin-treated rat retinas throughout the experimental period. In addition, retinal injury, evaluated by immunolabeling with an antibody against glial fibrillary acidic protein, was markedly reduced in anthocyanin-treated retinas. These results demonstrate that anthocyanins extracted from black soybean seeds can protect retinal neurons from MNU-induced structural and functional damages, suggesting that anthocyanins from black soybean seed coat may be used as a useful supplement to modulate RD.