The glycolysis/HIF-1α axis defines the inflammatory role of IL-4-primed macrophages.

T helper type 2 (Th2) cytokine-activated M2 macrophages contribute to inflammation resolution and wound healing. This study shows that IL-4-primed macrophages exhibit a stronger response to lipopolysaccharide stimulation while maintaining M2 signature gene expression. Metabolic divergence between canonical M2 and non-canonical proinflammatory-prone M2 (M2INF) macrophages occurs after the IL-4Rα/Stat6 axis. Glycolysis supports Hif-1α stabilization and proinflammatory phenotype of M2INF macrophages. Inhibiting glycolysis blunts Hif-1α accumulation and M2INF phenotype. Wdr5-dependent H3K4me3 mediates the long-lasting effect of IL-4, with Wdr5 knockdown inhibiting M2INF macrophages. Our results also show that the induction of M2INF macrophages by IL-4 intraperitoneal injection and transferring of M2INF macrophages confer a survival advantage against bacterial infection in vivo. In conclusion, our findings highlight the previously neglected non-canonical role of M2INF macrophages and broaden our understanding of IL-4-mediated physiological changes. These results have immediate implications for how Th2-skewed infections could redirect disease progression in response to pathogen infection.

Seasonal flexibility of the gut structure and physiology in Eremias multiocellata.

Although gut seasonal plasticity has been extensively reported, studies on physiological flexibility, such as water-salt transportation and motility in reptiles, are limited. Therefore, this study investigated the intestinal histology and gene expression involved in water-salt transport (AQP1, AQP3, NCC, and NKCC2) and motility regulation (nNOS, CHRM2, and ADRB2) in desert-dwelling Eremias multiocellata during winter (hibernating period) and summer (active period). The results showed that mucosal thickness, the villus width and height, the enterocyte height of the small intestine, and the mucosal and submucosal thicknesses of the large intestine were greater in winter than in summer. However, submucosal thickness of the small intestine and muscularis thickness of the large intestine were lower in winter than in summer. Furthermore, AQP1, AQP3, NCC, nNOS, CHRM2, and ADRB2 expressions in the small intestine were higher in winter than in summer; AQP1, AQP3, and nNOS expressions in the large intestine were lower in winter than in summer, with the upregulation of NCC and CHRM2 expressions; no significant seasonal differences were found in intestinal NKCC2 expression. These results suggest that (i) intestinal water-salt transport activity is flexible during seasonal changes where AQP1, AQP3 and NCC play a vital role, (ii) the intestinal motilities are attenuated through the concerted regulation of nNOS, CHRM2, and ADRB2, and (iii) the physiological flexibility of the small and large intestine may be discrepant due to their functional differences. This study reveals the intestinal regulation and adaptation mechanisms in E. multiocellata in response to the hibernation season.

Regulation of salt tolerance in the roots of Zea mays by L-histidine through transcriptome analysis.

Soil salinization is an important worldwide environmental problem and the main reason to reduce agricultural productivity. Recent findings suggested that histidine is a crucial residue that influences the ROS reduction and improves the plants' tolerance to salt stress. Herein, we conducted experiments to understand the underlying regulatory effects of histidine on maize root system under salt stress (100 mM NaCl solution system). Several antioxidant enzymes were determined. The related expressed genes (DEGs) with its pathways were observed by Transcriptome technologies. The results of the present study confirmed that histidine can ameliorate the adverse effects of salt stress on maize root growth. When the maize roots exposed to 100 mM NaCl were treated with histidine, the accumulation of superoxide anion radicals, hydrogen peroxide, and malondialdehyde, and the content of nitrate nitrogen and ammonium nitrogen were significantly reduced; while the activities of superoxide dismutase, peroxidase, catalase, nitrate reductase, glutamine synthetase, and glutamate synthase were significantly increased. Transcriptome analysis revealed that a total of 454 (65 up-regulated and 389 down-regulated) and 348 (293 up-regulated and 55 down-regulated) DEGs were observed when the roots under salt stress were treated with histidine for 12 h and 24 h, respectively. The pathways analysis of those DEGs showed that a small number of down-regulated genes were enriched in phytohormone signaling and phenylpropanoid biosynthesis at 12 h after histidine treatment, and the DEGs involved in the phytohormone signaling, glycolysis, and nitrogen metabolism were significantly enriched at 24 h after treatment. These results of gene expression and enzyme activities suggested that histidine can improve the salt tolerance of maize roots by enriching some DEGs involved in plant hormone signal transduction, glycolysis, and nitrogen metabolism pathways.

Seasonal flexibility of kidney structure and factors regulating water and salt in Eremias multiocellata.

Although sodium and water reabsorption by the kidney plays a major role in maintaining body fluid homeostasis, the seasonal response of renal morphology and the factors involved in water and salt regulation are not well known, especially in reptiles. Eremias multiocellata is a typical desert-dwelling lizard. Here, we compared water and salt regulation of E. multiocellata in winter (hibernation), spring (emerging from hibernation), and summer (active) according to histomorphometry and the expression of genes such as those encoding aquaporins (AQP1, AQP2, AQP3), the Na+-Cl- cotransporter (NCC), the Na+-K+-2Cl- cotransporter (NKCC2), renin (Ren), angiotensin II receptor type 2 (AT2R), and endothelial nitric oxide synthase (eNOS) in the kidneys. The results showed that the area of Bowman's capsule and the glomerular density were lower in winter compared to summer and spring, and the lumen size of the DCT, PCT, and IS was greater in spring than in summer. Compared to summer and spring, the expression of AQP1, AQP3, NCC, NKCC2, Ren, and eNOS was significantly decreased in winter, whereas the expression of AQP2 and AT2R remained high. These results indicate that E. multiocellata balances its water budget via morpho-functional changes in different seasons. Although renal function was temporarily attenuated during winter, the regulation of aquaporins genes was not synchronous, indicating the complexity and particularity of water and salt regulation in desert lizards when facing the constraints of harsh environmental conditions, seasonal variations, and hibernation. These results will enrich the understanding of water and salt regulation mechanisms in desert reptiles.

Retraction Note to: Substrates specificity of tannase from Streptomyces sviceus and Lactobacillus plantarum.

The Editor-in-Chief has retracted this article (Wang et al. 2018) because the authors do not have ownership of the data they report. An investigation by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) has concluded that the data reported in this article are the sole property of the CSIRO. Mingbo Wu agrees with this retraction. Dan Wang, Yao Liu, Die Lv, Xueli Hu, Qiumei Zhong and Ye Zhao have not responded to correspondence about this retraction.

Substrates specificity of tannase from Streptomyces sviceus and Lactobacillus plantarum.

Tannases can catalyze the hydrolysis of galloyl ester and depside bonds of hydrolysable tannins to release gallic acid and glucose, but tannases from different species have different substrate specificities. Our prior studies found that tannase from Lactobacillus plantarum (LP-tan) performed a higher esterase activity, while the tannase from Streptomyces sviceus (SS-tan) performed a higher depsidase activity; but the molecular mechanism is not elucidated. Based on the crystal structure of LP-tan and the amino acid sequences alignment between LP-tan and SS-tan, we found that the sandwich structure formed by Ile206-substrate-Pro356 in LP-tan was replaced with Ile253-substrate-Gly384 in SS-tan, and the flap domain (amino acids: 225-247) formed in LP-tan was missed in SS-tan, while a flap-like domain (amino acids: 93-143) was found in SS-tan. In this study, we investigated the functional role of sandwich structure and the flap (flap-like) domain in the substrate specificity of tannase. Site-directed mutagenesis was used to disrupt the sandwich structure in LP-tan (P356G) and rebuilt it in SS-tan (G384P). The flap in LP-tan and the flap-like domain in SS-tan were deleted to construct the new variants. The activity assay results showed that the sandwich and the flap domain can help to catalytic the ester bonds, while the flap-like domain in SS-tan mainly worked on the depside bonds. Enzymatic characterization and kinetics data showed that the sandwich and the flap domain can help to catalytic the ester bonds, while the flap-like domain in SS-tan may worked on the depside bonds.