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The iron (Fe) metabolism plays important role in regulating systemic metabolism and obesity development. The Fe inside cells can form iron-sulfur (Fe-S) clusters, which are usually assembled into target proteins with the help of a conserved cluster assembly machinery. Family with sequence similarity 96A (FAM96A; also designated CIAO2A) is a cytosolic Fe-S assembly protein involved in the regulation of cellular Fe homeostasis. However, the biological function of FAM96A in vivo is still incompletely defined. Here, we tested the role of FAM96A in regulating organismal Fe metabolism, which is relevant to obesity and adipose tissue homeostasis. We found that in mice genetically lacking FAM96A globally, intracellular Fe homeostasis was interrupted in both white and brown adipocytes, but the systemic Fe level was normal. FAM96A deficiency led to adipocyte hypertrophy and organismal energy expenditure reduction even under nonobesogenic normal chow diet-fed conditions. Mechanistically, FAM96A deficiency promoted mechanistic target of rapamycin (mTOR) signaling in adipocytes, leading to an elevation of de novo lipogenesis and, therefore, fat mass accumulation. Furthermore, it also caused mitochondrial defects, including defects in mitochondrial number, ultrastructure, redox activity, and metabolic function in brown adipocytes, which are known to be critical for the control of energy balance. Moreover, adipocyte-selective FAM96A knockout partially phenocopied global FAM96A deficiency with adipocyte hypertrophy and organismal energy expenditure defects but the mice were resistant to high-fat diet-induced weight gain. Thus, FAM96A in adipocytes may autonomously act as a critical gatekeeper of organismal energy balance by coupling Fe metabolism to adipose tissue homeostasis.

Glucose homeostasis of adipocytes could be regulated by immune-adipose crosstalk. In order to investigate the effects of Lymphotoxin-like inducible protein that competes with glycoprotein D for herpesvirus entry on T cells (LIGHT) on glucose metabolism, we performed the present study. Our results showed that LIGHT deficiency improved glucose tolerance and enhanced glucose consumption of inguinal white adipose tissue (iWAT) under high fat diet. Consistently, Light overexpression could inhibit glucose uptake during the process of white adipogenesis. Mechanistically, LIGHT interacted with lymphotoxin-β receptor (LTβR) to attenuate AKT pathway leading to downregulation of glucose transporter-4 (GLUT4) expression, which resulted in glucose uptake inhibition. In summary, our findings revealed LIGHT-LTβR-AKT-GLUT4 axis as a regulator of glucose uptake in adipose tissue, which suggested the pivotal role of LIGHT in maintaining glucose homeostasis.

In this work, a new N-halamine precursor with two epoxy groups, 1,3-bis(2,3-epoxypropyl)-s-triazine-2,4,6-trione (BETT), was synthesized and used to enhance the compatibility between poly(lactic acid) (PLA) and poly (butylene adipate-co-terephthalate) (PBAT). The rheological analysis and GPC indicated that chain extension between PLA and PBAT occurred during the melt-blending in the presence of BETT. The PLA/PBAT chain extensions improved the compatibility between PLA and PBAT and hindered the crystallization of PLA. SEM images showed that PLA/PBAT blend gradually changed from the typical sea-island phase without BETT to a co-continuous structure with increase in amount of BETT. This showed that the interfacial compatibility between PLA and PBAT improved significantly on addition of BETT. Moreover, compared to PLA/PBAT blend, the mechanical properties of PLA/PBAT/BETT blends showed great improvement. Furthermore, the chlorinated PLA/PBAT/BETT sheets displayed excellent antibacterial activities against E. coli (CMCC 44103) and S. aureus (ATCC 6538) cultures, wherein the sheets with 17.5 ± 0.8 μg/cm2 of the active chlorine could kill all inoculated bacteria within 30 min.

In this study, the structural characterization of Sphallerocarpus gracilis polysaccharide (SGP) and its hypoglycaemic activities are reported for the first time. SGP, which has a weight average molar mass (Mw) of 7.413×105, was isolated from Sphallerocarpus gracilis and purified by ion-exchange chromatography. The polysaccharide is composed of rhamnose, arabinose, mannose, glucose and galactose, with the molar ratio of 4.12: 8.99: 5.45: 65.94: 15.50. The mechanism underlying the hypoglycaemic effect of SGP was evaluated. Experimental results showed that SGP protected pancreatic β-cells from alloxan damage by several possible mechanisms, including: (1) repairing free radical damage; (2) reducing the apoptosis of pancreatic β-cells by inhibiting the activities of caspase-3 and bax, and enhancing the activity of bcl-2; (3) stimulating insulin secretion and upregulating the pancreatic and duodenal homeobox 1 gene and the insulin gene and the pancreatic in pancreatic β-cells. The results obtained in this study suggest that SGP may be a promising therapeutic agent in the treatment of diabetes mellitus.

The pH-sensitive hydrogels composed of sodium caseinate (SC) and N,O-carboxymethyl chitosan (NOCC) were prepared and a new method to characterize the gelation process was presented in this work. Reological tests suggested that RSC/NOCC=3/7 (the weight ratio of SC and NOCC) was the best ratio of hydrogel. The well-developed three-dimensional network structures in the hydrogel were confirmed by AFM. Two structural parameters, tIS and tCS, denoted as the initial and critical structure formation time, respectively, were used to provide an exact determination of the start of structure formation and description of gelation process. The gelation process strongly depended on temperature changes, a high temperature resulted in an early start of gelation. The non-kinetic model suggested the higher activation energy in the higher temperatures was disadvantageous to structure formation, and vice versa. Due to the smart gel reported here was very stable at room temperature, we believed that the gel is required for applications in drug delivery or could be exploited in the development of potential application as molecular switches in the future.

Sphallerocarpus gracilis (S. gracilis) is a little-investigated edible plant and used as traditional Chinese medicine. In this study, polysaccharide extracted from S. gracilis,deproteined and purified. The polysaccharide (SGP) was chemically modified to obtain its sulfated derivatives (S-SGP) using the method of chlorosulfonic acid/pyridine (CSA/Pyr). In order to acquire the derivative with the highest degree of substitution (DS), the optimum conditions of the sulfation were obtained based on response surface design (RSD), and the structural characterizations and antioxidant properties of the S-SGP were comparatively investigated by Fourier transform infrared spectrometry (FT-IR), GC-MS analysis, size exclusion chromatography (SEC), and DPPH radical assay, hydroxyl radical assay, superoxide radical assay, and reducing power assay, respectively. Results showed that the modification was successful, and obtained the optimum combination of conditions. Compared with SGP, the sulfated polysaccharide with relatively the decreased degree of molecular weight (Mw) but the same composition of monosaccharides exhibited better antioxidant activities in DPPH, hydroxyl, superoxide radical and reducing power assay. These results indicated that the antioxidant activities in vitro of the S-SGP from S. gracilis may be related to combined effects of Mw, monosaccharide composition, and sulfate content.

For centuries, Patrinia heterophylla had been used in China to treat many diseases including tumor. Triterpenes has been identified as the major active constituents in Patrinia heterophylla. To elucidate the antitumor mechanism of triterpenes from Patrinia heterophylla1 (TPH), a proteomic analysis is carried out with TPH treatment in K562 cells. The total proteins extracted from TPH treated K562 cells are analyzed by two dimensional gel electrophoresis (2-DE) and compared with those untreated K562 cells. Mass spectrometry is applied to identify the differentially expressed proteins. Twenty-three differentially expressed significant proteins are discovered. Eight proteins are later identified by mass spectrometry (MALDI-TOF-MS) and Mascot software. Among them, four proteins are up-regulated (Aldolase A, Glyceraldehyde-3-phosphate dehydrogenase, Flavin reductase and Hemoglobin subunit) and four proteins were down-regulated (Heat-shock protein 90 〈Alpha〉 (HSP90-〈Alpha〉), Eukaryotic translation initiation factor 5A, Moesin, tublin) by TPH treatment in K562 cells. The identified proteins are associated with energy metabolism, oxidative stress, apoptosis, signal transduction, differential induction, and protein biosynthesis. These findings might provide valuable insights into the antitumor mechanism of TPH in K562 cells.