Glutathione S-transferases (GSTs) are multifunctional enzymes that are widely distributed in different species. GSTs detoxify exogenous and endogenous substances by conjugation to reduced glutathione. We characterized BmGSTD4, an antenna-specific GST, in male silkmoths. The full-length mRNA of Bmgstd4 was cloned by RACE-PCR and contained an open reading frame of 738 bp encoding a 245 amino acid protein. The antenna specificity of BmGSTD4 was validated at the mRNA and protein levels and BmGSTD4 was shown to localize in the sensillum of male silkmoth antennae. Homology modeling and multi-sequence alignment suggested that BmGSTD4 was a typical GST belonging to the δ class and had a canonical GST fold with a conserved N-terminus, including a glutathione-binding site and a C-terminal domain harboring a hydrophobic substrate-binding site. Restricted expression of BmGSTD4 in silkmoth antennae combined with GST activity suggested that BmGSTD4 was involved in the detoxification of harmful chemicals.

The prophylactic effects of the polymethoxyflavones (PMFs) in long-leaf orange peel oil (OPO) were determined using an N^ω-nitro-L-arginine-induced hypertensive rat model. The OPO contained eight PMF components, namely sinensetin, hexamethoxyflavone, tetramethyl-O-isoscutellarein, nobiletin, tetramethyl-O-scutellarein, heptamethoxyflavone, 5-demethylnobiletin and tangeretin. After treatment with OPO, the SP (systolic pressure) and DP (diastolic pressure) in hypertensive rats were reduced. The NO (nitric oxide) contents in serum, heart, liver and kidney of OPO-treated N^ω-nitro-L-arginine (L-NNA)-induced hypertensive rats were higher than those in untreated hypertensive rats, but the MDA (malondialdehyde) contents in OPO-treated rats were lower than those of the control rats (untreated hypertensive rats). ET-1 (endothelin-1), VEGF (vascular endothelial growth factor) and E-selectin serum levels in hypertensive rats could be reduced, but the CGRP (calcium gene-related peptide) level could be increased by OPO treatment. The results of the qPCR assay showed that OPO upregulated HO-1 (heme oxygenase-1), nNOS (neuronal nitric oxide synthase) and eNOS (endothelial nitric oxide synthase) mRNA expression and downregulated ADM (adrenomedullin), RAMP2 (receptor activity modifying protein 2) and iNOS (inducible nitric oxide synthase) expression in hypertensive rats. The Western blot results also proved that OPO upregulated nNOS and eNOS protein expression and downregulated iNOS expression in hypertensive rats. Based on this study, we could conclude that OPO showed good antihypertensive effects, and the effect was concentration dependent.

p-Synephrine is a common alkaloid widely distributed in citrus fruits. However, the effects of p-synephrine on the metabolic profiles of individuals with energy abnormalities are still unclear. In the study, we investigated the effect of p-synephrine on energy homeostasis and metabolic profiles using a high fat diet (HFD)-induced mouse model. We found that p-synephrine inhibited the gain in body weight, liver weight and white adipose tissues weight induced by HFD. p-Synephrine supplementation also reduced levels of serum total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) but not to a statistically significant degree. Histological analysis showed that HFD induced excessive lipid accumulation and glycogen loss in the liver and adipocyte enlargement in perirenal fat tissue, while p-synephrine supplementation reversed the changes induced by HFD. Moreover, HFD feeding significantly increased mRNA expression levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) and reduced the mRNA expression level of interleukin-10 (IL-10) compared to the control group, while p-synephrine supplementation significantly reversed these HFD-induced changes. Liver and serum metabolomic analysis showed that p-synephrine supplementation significantly altered small molecule metabolites in liver and serum in HFD mice and that the changes were closely associated with improvement of energy homeostasis. Notably, amino acid metabolism pathways, both in liver and serum samples, were significantly enriched. Our study suggests that p-synephrine improves energy homeostasis probably by regulating amino acid metabolism in HFD mice, which provides a novel insight into the action mechanism of p-synephrine modulating energy homeostasis.

Global fruit production is excessive, and fruit wine is a significant outcome of fruit processing. The pigment in fruit wine gives it a vibrant color and affects its quality, taste, and marketing. The pigments in fruit wines are commonly divided into three categories: anthocyanins, carotenoids, and chlorophylls. They are naturally synthesized pigments in plants that undergo complex biochemical changes that eventually tend to be stable in mature fruit wine, showing the color properties desired by consumers. Under normal circumstances, pigment molecules are unstable and have isomers, which makes it difficult to accurately identify and control them. In addition, biochemical changes produce a series of chemical derivatives that affect bioavailability and biological functions. This review summarizes the chemical basis, formation process, influencing factors, identification techniques, bioavailability, and bioactivity of fruit wine pigments, providing an important reference for the utilization of fruit resources and the development of high-quality fruit wine products.