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Xylaria nigripes (XN) is a medicinal fungus with a high-economic value. The aim of this study was to explore the hypoglycemic effects and mechanisms of the XN aqueous extract in steroid-induced insulin-resistant (SIIR) rats. Significant hypoglycemic effects were observed 60 min after administration of XN aqueous extract. In normal Wistar, hypoglycemic effects were 21% (the plasma glucose level decreased from 128.6 ± 12.5 to 100.9 ± 10.7 mg/dL). In SIIR, hypoglycemic effects were 26% (the plasma glucose level decreased from 177.6 ± 12.5 to 133.3 ± 29.7 mg/dL) rats refer to their baseline. The signaling proteins for insulin-receptor substrate-1 and glucose transporter-4 increased 0.51-fold and 1.12-fold, respectively, as determined by Western blotting; the increase in the proteins was 13% and 9%, respectively, as determined by immunohistochemistry. The serotonin antagonist, α-p-chlorophenylalanine, effectively blocked the hypoglycemic effects and increased the signaling protein levels. After XN administration, none of the animals showed significant changes in plasma-free fatty acids in 60 min. In summary, the XN extract may have hypoglycemic effects in normal Wistar and SIIR rats that may have a serotonin-related hypoglycemic effect and enhance insulin sensitivity in the SIIR rats. Copyright © 2015 John Wiley & Sons, Ltd.

Four new 5 beta,19-epoxycucurbitacins, kuguacins T-W (1-4, resp.), along with nine known cucurbitane derivatives, 5-13, were obtained from the fresh fruit of Momordica chrantia. Structures of the new metabolites were elucidated as 5 beta,19-epoxy-25-hydroxycucurbitane-3,7,23-trione (1), 5 beta,19-epoxy-3,7-dioxo-23,24,25,26,27-pentanorcucurbitan-22-oic acid (2), 5 beta,19-epoxy-3 beta-hydroxycucurbit-24-ene-7,23-dione (3), and 5 beta, 19-epoxy-25-hydroxycucurbit-23-ene-3,7-dione (4), by extensive spectroscopic investigations, which were confirmed by a single-crystal X-ray diffraction analyses in the case of compound 4.

Phenylethanoid glycosides are a group of phenolic compounds with diverse biological activities such as hypotensive, diuretic, and hypoglycemic effects. In this study, a target profiling analysis approach using ultra-performance liquid chromatography coupled with tandem quadrupole mass spectrometry (MS) was established on the basis of parent ion scanning for m/z 161, the characteristic product ion for phenylethanoid glycosides. It was successfully employed to discriminate the chemical composition of phenylethanoid glycosides between Plantaginis Herba and Plantaginis Semen, two medicinal parts of Plantago plants, which are widely used as herbal medicine in China. Totally, 34 phenylethanoid glycosides were characterized and tentatively identified by their retention times, MS, and tandem quadrupole MS (MS/MS) data. Combined with chemometrics analysis of principal component analysis and orthogonal projection to latent structural discriminate analysis, eight of them, especially acteoside and plantamajoside, were picked out and contributed to the chemical distinction between Plantaginis Herba and Plantaginis Semen, which might be responsible for the differences in diuretic and hypotensive effects between the two medicinal parts. This new approach for target profiling provides not only a novel idea for specific analysis of active chemical constituents in the same type, but also a promising and reference method for quality evaluation of traditional Chinese medicines.

Banaba (Lagerstroemia speciosaL.) extracts have been used for many years in folk medicine to treat diabetes, with the first published research study being reported in 1940. This review summarizes the current literature regarding banaba and its constituents. The hypoglycemic effects of banaba have be

N-(4-aminobenzenesulfonyl)-N′-butylurea (8) (glibutamide®) and several amino compounds were grafted on water soluble and non-toxic polymeric backbones, with the intention to study the influence of such a carrier on the hypoglycemic effects of the drug, covalently linked by ester and (or) amide bonds. The spacer by which the drug was fixed to the polymeric carrier contained 1 to 10 atoms. So far, the hypoglycemic effect of only one polymer (13d) was tested. It showed, however, negative results probably due to the amide bond of the drug which is difficult to split off.

The introduction of the orally active hypoglycemic agents has already had a profound effect on the therapy of diabetes. Unfortunately, despite a great deal of discussion in the literature, there is still much about these drugs which is uncertain and unsettled and, in general, information about their limitations is not so widely spread as claims for their utility. Although the modern era of interest in oral hypoglycemic agents began about 40 years ago with the association of this effect with the guanidines, it was first observed and confirmed more than 80 years ago as the result of salicylate therapy. Hypoglycemic effects have been noted after the oral administration of such unrelated materials as (1) sulfonamides and sulfonylureas (e.g., tolbutamide), (2) guanidines (e.g., synathalin A), (3) extracts of the akee plant (hypoglycin A and B), and (4) salicylates. It is also reasonable to suppose that more are on their way. The state of our knowledge of the modes of action of the several groups of orally active hypoglycemic agents based on clinical and experimental observations as well as their clinical uses, limitations, and dangers are discussed.

alpha-Substituted-beta-arylpropionic acid derivatives were prepared and examined for hypolipidemic activity. The structure-activity relationship study showed that a chloro substituent at the alpha-position and an aryloxy or aralkyloxy substituent on the beta-aryl moiety was necessary for possession of substantial activity. In addition, some of these compounds showed hypolipidemic and hypoglycemic effects on diabetic mice. Among the 71 compounds prepared, ethyl 2-chloro-3-[4-(4-chlorobenzyloxy)phenyl]propionate (12) and ethyl 2-chloro-3-[4-(1-phenylethyloxy)phenyl]propionate (24) were the best with respect to activity and toxicity.