Effects of yam dioscorin interventions on improvements of the metabolic syndrome in high-fat diet-induced obese rats

Abstract

BackgroundThe metabolic syndrome (MS) is termed a cluster of multiple metabolic risk criteria which is positively correlated with cardiovascular disease and type 2 diabetes mellitus (DM). Yam dioscorins have been reported to exhibit biological activities, however, little is known their preventive effects on the MS. Therefore, a high-fat (HF) diet was used to induce Wistar rat obesity and then yam dioscorin (50 mg/kg, dio50) was intervened daily concurrent HF diet (HF diet + dio50) for five weeks to check the changes of weights of body and tissues, blood pressures, and impaired glucose tolerances. The in vitro peptic hydrolysates of dioscorin with molecular mass between 3 kDa and 10 kDa and less than 3 kDa were used to determine dipeptidyl peptidase IV (DPP IV) inhibitory activities which DPP IV inhibitor has been reported to prevent and treat type 2 DM.ResultsThere were no significant difference in body weights, feed intakes, feed conversion, and weights of adipose tissues of obese rats in groups of HF and (HF diet + dio50). However, the systolic blood pressures in obese rats of 2-, 3- and 4-week dioscorin interventions were showed significantly lower (P < 0.05) compared to the HF group. The dioscorin intervention (HF+ dio50) was showed significantly different (P < 0.05) and improved the impaired glucose tolerances compared to HF group in obese rats by the oral glucose tolerance tests. It was also found that the fraction with different molecular mass of dioscorin peptic hydrolysates (5 mg/ml) showed inhibitory activities against DPP IV using sitagliptin phosphate as positive controls.ConclusionsYam dioscorins exhibit improved MS activities in obese rats which the related mechanisms may need further investigations.Electronic supplementary materialThe online version of this article (doi:10.1186/s40529-015-0084-8) contains supplementary material, which is available to authorized users.

Could consumption of yam (Dioscorea) or its extract be beneficial in controlling glycaemia: a systematic review

“…All the included studies measured glucose and, although these were measured via a variety of methods (FBG/GTT), they all showed that treatment with either yam or its extract led to significant improvements in glucose tolerance compared to the controls (Table 2). FBG was reported in all studies except Wu et al (2018) and Shih et al (2015), while GTT was measured in five of the ten studies (Xu et al 2020;Wu et al 2018;Shih et al 2015;Kim et al 2012;Hsu et al 2007). Dioscin, dioscorin, DA-9801, DA-9802, Diosgenin and CYP improved FBG (P<0.05), while dioscin, dioscorin, DA-9802 were shown to improve GTT from 30 minutes to 120 minutes after oral or intraperitoneal glucose load (P<0.05).…”

“…In the rodent model T2DM was induced by consuming high fat diet (HFD) in rats or mice, the KK-A y mice, which spontaneously exhibit T2DM and the db/db mice, a genetic model of T2DM were fed HFD, while the OLETF mice fed normal diet; one study, Hsu et al (2007) fed the rodent model rats with high fructose diet to induce hyperglycaemia. The studies utilised a variety of Dioscorea species although two studies (Li et al 2019;Shih et al 2015) did not mention the yam species. A variety of yam extracts were used in nine of the studies; these included components, Dioscin (Xu et al 2020;Li et al 2019), Dioscorin (Wu et al 2018;Shih et al 2015), Diosgenin (Hashidume et al 2018) and DA-9802 (Moon et al 2014;Kim et al 2012) and Dioscorea esculenta powder (Sato et al 2017); while one study used raw material of Dioscorea Oppesita, (a synonym of two species of yam Discorea polystachya and Dscorea oppositifolioa) (Hsu et al 2007).…”

“…The studies utilised a variety of Dioscorea species although two studies (Li et al 2019;Shih et al 2015) did not mention the yam species. A variety of yam extracts were used in nine of the studies; these included components, Dioscin (Xu et al 2020;Li et al 2019), Dioscorin (Wu et al 2018;Shih et al 2015), Diosgenin (Hashidume et al 2018) and DA-9802 (Moon et al 2014;Kim et al 2012) and Dioscorea esculenta powder (Sato et al 2017); while one study used raw material of Dioscorea Oppesita, (a synonym of two species of yam Discorea polystachya and Dscorea oppositifolioa) (Hsu et al 2007). The yam and/or extracts were obtained via various methods; five articles reported their extraction methods from raw yam (Xu et al 2020;Moon et al 2014;Kim et al 2012;Cheng et al 2019;Wu et al 2018) while two articles purchased the yam from external sources (Hashidume et al 2018;Hsu et al 2007).…”

The perceptions of natural compounds against dipeptidyl peptidase 4 in diabetes: from in silico to in vivo

“…121 The protein hydrolysates from whey, barbel, and yam can reduce the DPP-4 activity in enzymatic measurements. 122–125 Through partition by molecular sieve, the highest inhibition peptide sequences of DPP-4 such as Ala-Pro, Leu-Pro-Val-Pro-Gln, Trp-Ser-Gly, and Phe-Ser-Asp have been found. 126–128 Nevertheless, these results from in vitro enzymatic assays cannot guarantee a promising future since physiological regulation of DPP-4 is far more complicated than bench-top experiments.…”

Additional Benefit of Chinese Medicine Formulae Including Dioscoreae rhizome (Shanyao) for Diabetes Mellitus: Current State of Evidence

“…The metabolic syndrome is a term for cluster of multiple metabolic risk criteria which is positively correlated with type 2 diabetes mellitus. Shanyao dioscorin interventions exhibit improved metabolic syndrome activities in obese rats, and peptic hydrolysates of Shanyao dioscorin in vitro exhibit DPP IV inhibitory activities (93).…”