A new flavan-3-ol lactone and other constituents from Euonymus alatus with inhibitory activities on α-glucosidase and differentiation of 3T3-L1 cells

Flavonoids as dual-target inhibitors against α-glucosidase and α-amylase: a systematic review of in vitro studies

Diabetes mellitus remains a major global health issue, and great attention is directed at natural therapeutics. This systematic review aimed to assess the potential of flavonoids as antidiabetic agents by investigating their inhibitory effects on α-glucosidase and α-amylase, two key enzymes involved in starch digestion. Six scientific databases (PubMed, Virtual Health Library, EMBASE, SCOPUS, Web of Science, and WHO Global Index Medicus) were searched until August 21, 2022, for in vitro studies reporting IC50 values of purified flavonoids on α-amylase and α-glucosidase, along with corresponding data for acarbose as a positive control. A total of 339 eligible articles were analyzed, resulting in the retrieval of 1643 flavonoid structures. These structures were rigorously standardized and curated, yielding 974 unique compounds, among which 177 flavonoids exhibited inhibition of both α-glucosidase and α-amylase are presented. Quality assessment utilizing a modified CONSORT checklist and structure-activity relationship (SAR) analysis were performed, revealing crucial features for the simultaneous inhibition of flavonoids against both enzymes. Moreover, the review also addressed several limitations in the current research landscape and proposed potential solutions. The curated datasets are available online at https://github.com/MedChemUMP/FDIGA .

Exploring Active Ingredients, Beneficial Effects, and Potential Mechanism of Allium tenuissimum L. Flower for Treating T2DM Mice Based on Network Pharmacology and Gut Microbiota

Forty compounds were isolated and characterized from A. tenuissimum flower. Among them, twelve flavonoids showed higher α−glucosidase inhibition activities in vitro than acarbose, especially kaempferol. The molecular docking results showed that the binding of kaempferol to α−glucosidase (GAA) could reduce the hydrolysis of substrates by GAA and reduce the glucose produced by hydrolysis, thus exhibiting α−glucosidase inhibition activities. The in vivo experiment results showed that flavonoids−rich A. tenuissimum flower could decrease blood glucose and reduce lipid accumulation. The protein expression levels of RAC−alpha serine/threonine−protein kinase (AKT1), peroxisome proliferator activated receptor gamma (PPARG), and prostaglandin G/H synthase 2 (PTGS2) in liver tissue were increased. In addition, the Firmicutes/Bacteroidetes (F/B) ratio was increased, the level of gut probiotics Bifidobacterium was increased, and the levels of Enterobacteriaceae and Staphylococcus were decreased. The carbohydrate metabolism, lipid metabolism, and other pathways related to type 2 diabetes mellitus were activated. This study indicating flavonoids−rich A. tenuissimum flower could improve glycolipid metabolic disorders and inflammation in diabetic mice by modulating the protein expression and gut microbiota.

Ruby chocolate: A study of its phytochemical composition and quantitative comparison with dark, milk and white chocolate

Ruby chocolate was introduced in 2017 as the fourth type of chocolate, in addition to white, milk and dark chocolate. However, until now not much is reported about its phytochemical composition. Therefore, we analyzed ruby chocolate by UPLC-HRMS, together with the three other types of chocolate. Feature-based molecular networking was carried out to aid in the identification, while a set of 51 reference compounds were analyzed simultaneously for targeted quantification. In this way, a total of 54 compounds could be (tentatively) identified in the chocolates, of which 43 were found in the ruby chocolate. Moreover, 19 compounds were quantified, of which 13 in the ruby chocolate. The compounds include flavan-3-ols, proanthocyanidins and methylxanthines, but also biogenic amines and alkaloids. In general, ruby chocolate contained lower levels of these constituents compared to dark chocolate. However, A-type proanthocyanidins were found to be characteristic for the ruby chocolate.

Traditional uses, botany, phytochemistry, pharmacology, separation and analysis technologies of Euonymus alatus (Thunb.) Siebold: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Euonymus alatus (Thunb.) Siebold (E. alatus), a well-known medicinal plant, has been widely used thousands of years in China for the treatment of various diseases such as urticaria, dysmenorrhea, wound, dysentery, blood stasis, rheumatism and arthritis. Due to the extensive application of E. alatus in the fields of ethnopharmacological usage, the pharmaceutical researches of E. alatus keeps deepening.

AIM OF THE STUDY

This paper reviewed and summarized the integrated research progress of this medicinal plant. A comprehensive summary and comparison of traditional usages, botany, phytochemistry, pharmacology, toxicology, separation and analysis technologies of the E. alatus highlight recent scientific advances, which provides new insights into the research and development of this medicinal plant and would be helpful to promote the research situation of underlying pharmacological mechanisms and further utilizations of E. alatus.

MATERIAL AND METHODS

Literature survey was carried out via classic books of herbal medicine, PhD. and MSc. Dissertations. Online scientific databases including Pubmed, SciFinder, Science Direct, Scopus, the Web of Science, Google Scholar, China National Knowledge Infrastructure (CNKI) and others were searched up to February 2020 to identify eligible studies. All literatures of the research subject are analyzed and summarized in this review.

RESULTS

The E. alatus has been widely used in traditional practice in China, Korea and other Asian Countries. In the study of phytochemistry, more than 230 chemical constituents have been isolated and identified from E. alatus, including sesquiterpenoids, diterpenoids, triterpenoids, flavonoids, phenylpropanoids, lignans, steroids, alkaloids and other compounds. Among them, literature reports show that flavonoids and steroids are the most important bioactive substances found in this plant. A number of researches also have shown that extracts and compounds from E. alatus exert a wide spectrum of pharmacological effects, including antidiabetic effect, anti-tumor effects, anti-inflammatory effects, hepatoprotective effects, antioxidant effects, antibacterial effects, as well as other effects. However, most of the studies without clinical research. Research into plant's toxicological effects has also been limited. In addition, this review also summarizes and compares the separation and analysis technologies of E. alatus.

CONCLUSIONS

E. alatus has potential for the treatment of many diseases, especially tumors and diabetes. But many traditional uses of E. alatus have not been validated by current investigations. Additionally, modern studies haven't gone far enough into its pharmacological effects and the corresponding chemical constituents, more efforts should be made to illuminate the underlying mechanisms of E. alatus for treatment of tumors and diabetes. Moreover, the toxicological effects of this plant can be further studied. Currently, there are limited studies on its side effects and toxicological effects, which should provide further guidance for the safety of clinical use.

Phenolic compounds of the Australian native herb Prostanthera rotundifolia and their biological activities

The chemical identity and bioactivities of phenolic components of the Australian native herb Prostanthera rotundifolia were studied. Phenolic compounds were extracted with 80% (v/v) aqueous methanol and purified by liquid chromatography. The antioxidant capacity of the extract and its inhibiting activity against α-glucosidase, pancreatic lipase and hyaluronidase were determined. Phenolic compounds were identified by a combination of HPLC-PDA, LC-high resolution MS (LC-HRMS), LC-tandem MS (LC-MS/MS) and nuclear magnetic resonance (NMR) spectroscopy. Compared to spearmint, mint bush showed comparable antioxidant capacity, stronger inhibitory activity on pancreatic lipase and comparable and lower activity on α-glucosidase and hyaluronidase, respectively. Major compounds identified were verbascoside (48.8%), 4-methoxycinnamic acid (36.4%), p-coumaric acid glucose ester (9.2%) and 1-O-β-d-glucopyranosyl sinapate (5.6%), while caffeic acid, p-coumaric acid, hesperidin and naringenin were present in trace quantities. 4-Methoxycinnamic acid, p-coumaric acid glucose ester and 1-O-β-d-glucopyranosyl sinapate were identified for the first time in the genus of Prostanthera.

Euonymus alatus: A Review on Its Phytochemistry and Antidiabetic Activity

Euonymus alatus (E. alatus) is a medicinal plant used in some Asian countries for treating various conditions including cancer, hyperglycemia, and diabetic complications. This review outlines the phytochemistry and bioactivities of E. alatus related to antidiabetic actions. More than 100 chemical constituents have been isolated and identified from E. alatus, including flavonoids, terpenoids, steroids, lignans, cardenolides, phenolic acids, and alkaloids. Studies in vitro and in vivo have demonstrated the hypoglycemic activity of E. alatus extracts and its certain constituents. The hypoglycemic activity of E. alatus may be related to regulation of insulin signaling and insulin sensitivity, involving PPARγ and aldose reductase pathways. Further studies on E. alatus and its bioactive compounds may help to develop new agents for treating diabetes and diabetic complications.