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To understand the mechanisms of agricultural ecosystem structure and function in response to soil water deficit under future elevated atmospheric CO2 concentration, we examined the effects of soil water deficit and elevated CO2 concentration ([CO2]) on the stomatal traits, leaf photosynthesis, water use efficiency as well as Rubisco activity and gene expression of winter wheat with environmental growth chambers, whereby the [CO2] was controlled accurately with CO2 sensors. Our results showed that water deficit significantly decreased the plant biomass and net photosynthesis rates (Pn) of winter wheat by 33% and 29%, whereas elevated [CO2] partially mitigated the negative effects of water deficit on plant growth and physiological processes of winter wheat. Meanwhile, water deficit also reduced the stomatal width and regularity of stomatal distribution pattern on winter wheat leaves, but higher [CO2] could optimize the leaf gas exchange efficiency with more regular distribution pattern of stomata. Moreover, elevated [CO2] not only enhanced the Pn of winter wheat plants under water deficit, but also substantially reduced the transpiration rates (Tr) by 25%, and thus elevated [CO2] increased the water use efficiency by 61% when winter wheat plants subjected to water deficit. In addition, elevated [CO2] boosted the initial activity and activation state of Rubisco as well as soluble protein content by 66%, 38%, and 15%, and meanwhile significantly enhanced the gene expression levels of RbcL3 and RbcS2 by 453% and 417%, respectively. These results suggested that elevated [CO2] may optimize leaf gas exchange through modifying stomatal traits as well as the activity and gene express of Rubisco, and thus increased plant biomass, Pn, and water use efficiency to efficiently alleviate the physiological stress of water deficit on growth and development processes of winter wheat. Our findings may not only provide data for further understanding the impacts of water deficit on grain yield and water use efficiency of winter wheat under elevated [CO2], but also have important significance for adaptation management of agricultural ecosystems under global change. [ABSTRACT FROM AUTHOR]

Glutamine, like glucose, is a major nutrient consumed by cancer cells, yet these cells undergo glutamine starvation in the cores of tumors, forcing them to evolve adaptive metabolic responses. Pharmacologically targeting glutamine metabolism or withdrawal has been exploited for therapeutic purposes, but does not always induce cancer cell death. The mechanism by which cancer cells adapt to resist glutamine starvation in cisplatin-resistant non-small-cell lung cancer (NSCLC) also remains uncertain. Here, we report the potential metabolic vulnerabilities of A549/DDP (drug-resistant human lung adenocarcinoma cell lines) cells, which were more easily killed by the iron chelator deferoxamine (DFO) during glutamine deprivation than their parental cisplatin-sensitive A549 cells. We demonstrate that phenotype resistance to cisplatin is accompanied by adaptive responses during glutamine deprivation partly via higher levels of autophagic activity and apoptosis resistance characteristics. Moreover, this adaptation could be explained by sustained glucose instead of glutamine-dominant complex II-dependent oxidative phosphorylation (OXPHOS). Further investigation revealed that cisplatin-resistant cells sustain OXPHOS partly via iron metabolism reprogramming during glutamine deprivation. This reprogramming might be responsible for mitochondrial iron-sulfur [Fe-S] cluster biogenesis, which has become an "Achilles' heel," rendering cancer cells vulnerable to DFO-induced autophagic cell death and apoptosis through c-Jun N-terminal kinase (JNK) signaling. Finally, in vivo studies using xenograft mouse models also confirmed the growth-slowing effect of DFO. In summary, we have elucidated the adaptive responses of cisplatin-resistant NSCLC cells, which balanced stability and plasticity to overcome metabolic reprogramming and permitted them to survive under stress induced by chemotherapy or glutamine starvation. In addition, for the first time, we show that suppressing the growth of cisplatin-resistant NSCLC cells via iron chelator-induced autophagic cell death and apoptosis was possible with DFO treatment. These findings provide a solid basis for targeting mitochondria iron metabolism in cisplatin-resistant NSCLC for therapeutic purposes, and it is plausible to consider that DFO facilitates in the improvement of treatment responses in cisplatin-resistant NSCLC patients. [ABSTRACT FROM AUTHOR]

To the Editor, Group 2 innate lymphoid cells (ILC2s) produce the canonical type 2 cytokines interleukin (IL)-5 and IL-13 in response to epithelial cytokines IL-25, IL-33, and thymic stromal lymphopoietin (TSLP).[1] ILC2s have been to be involved in the pathogenesis of asthma, allergic rhinitis (AR) and atopic dermatitis (AD).[2] We have reported the higher ILC2 levels in patients with asthma and patients with AR.[[3]] Recently, the cysteinyl leukotriene (CysLT) D4 (LTD4) and LTE4 were reported to induce Th2 cytokine production from ILC2s.[[5]] LTE4 is the stable and dominant CysLT in the pathogenesis of allergic conditions. We found higher prevalence of ILC2s (Lin SP - sp CRTH2 SP + sp CD127 SP + sp cells, Figure A) and the higher expression of CysLT1R in ILC2s (Figure B-C B ) b from patients with AR compared to healthy controls. It suggests that the activation of ILC2s to LTC4, LTD4 but not LTE4 in AR is related to the increased expression of CysLT1R in AR, at least in our study. [Extracted from the article]

Background: Cultivated bananas are large, vegetatively-propagated members of the genus Musa. More than 1,000 cultivars are grown worldwide and they are major economic and food resources in numerous developing countries. It has been suggested that cultivated bananas originated from the islands of Southeast Asia (ISEA) and have been developed through complex geodomestication pathways. However, the maternal and parental donors of most cultivars are unknown, and the pattern of nucleotide diversity in domesticated banana has not been fully resolved. Methodology/Principal Findings: We studied the genetics of 16 cultivated and 18 wild Musa accessions using two single-copy nuclear (granule-bound starch synthase I, GBSS I, also known as Waxy, and alcohol dehydrogenase 1, Adh1) and two chloroplast (maturase K, matK, and the trnL-F gene cluster) genes. The results of phylogenetic analyses showed that all A-genome haplotypes of cultivated bananas were grouped together with those of ISEA subspecies of M. acuminata (A-genome). Similarly, the B- and S-genome haplotypes of cultivated bananas clustered with the wild species M. balbisiana (B-genome) and M. schizocarpa (S-genome), respectively. Notably, it has been shown that distinct haplotypes of each cultivar (A-genome group) were nested together to different ISEA subspecies M. acuminata. Analyses of nucleotide polymorphism in the Waxy and Adh1 genes revealed that, in comparison to the wild relatives, cultivated banana exhibited slightly lower nucleotide diversity both across all sites and specifically at silent sites. However, dramatically reduced nucleotide diversity was found at nonsynonymous sites for cultivated bananas. Conclusions/Significance: Our study not only confirmed the origin of cultivated banana as arising from multiple intra- and inter-specific hybridization events, but also showed that cultivated banana may have not suffered a severe genetic bottleneck during the domestication process. Importantly, our findings suggested that multiple maternal origins and a reduction in nucleotide diversity at nonsynonymous sites are general attributes of cultivated bananas. [ABSTRACT FROM AUTHOR]

Aim of study Tanshinone IIA is an active component of the traditional Chinese medicine. This study aimed at investigating the mechanism of tanshinone IIA on anti-atherosclerosis, which may be because of that Tanshinone IIA can affect the HDL subfractions distribution and then regulate reverse cholesterol transport. Materials and methods A model of hyperlipidaemia in rats was used. Tanshinone IIA was given daily after hyperlipidaemia. In vivo, lipid deposition and morphological changes in liver were analyzed; HDL subfractions and lipid level in serum as well as in liver were measured; the expression of genes related to cholesterol intake in liver and peritoneal macrophage cholesterol efflux were evaluated. In vitro, HepG2 cells and THP-1 cells were pretreated with tanshinone IIA and subsequently with ox-LDL to evaluate the total cholesterol and the expression of related genes. Results Tanshinone IIA reduced the lipid deposition in liver. Moreover, it did not affect the serum lipid levels but reduced the levels of HDL middle subfractions and increased the levels of HDL large subfractions. Furthermore, tanshinone IIA could regulate the expressions of CYP7A1, LDL-R, SREBP2 and LCAT in the liver as well as the ABCA1 and CD36 in macrophage cells which is involving in the cholesterol intake and efflux respectively. It could reduce lipid accumulation caused by ox-LDL induction, and that also regulate the expressions of LDL-R, HMGCR and SREBP2 in HepG2 and ABCA1, CD36 in THP-1 cells. Conclusion A novel finding that tanshinone IIA was not reduce the serum lipid level but affects the HDL subfractions distribution and thereby regulating the intake and efflux of cholesterol. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Salvia Miltiorrhiza Bunge (also known as herb Danshen in Chinese) is a widely used Chinese herbal medicine. Tanshinone IIA (TSN IIA) is considered to be the most important bioactive ingredient in Danshen and exhibits an anti-atherosclerotic activity. Aim of study: To evaluate the protective effect of TSN IIA on the human endothelial EA.hy926 cells injured by hydrogen peroxide in vitro and its possible mechanism. Materials and methods: The EA.hy926 cells were incubated for 24h with different concentrations of TSN IIA (5, 10 and 20μg/μL ) or DMEM. Subsequently, cells were treated with 300μmol/L H2O2 for another 4h. Then, the percentage of cell viability was evaluated by 3-(4, 5-di-methylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. The apoptosis of EA.hy926 cells was detected by flow cytometry with AnnexinV-FITC/PI double staining and laser scanning spectral confocal technique. The generation of intracellular reactive oxygen species (ROS) generation was analyzed by flow cytometry. The mRNA expressions of caspase-3, Bcl-2 and Bax were tested by real time-reverse transcription polymerase chain reaction (real time RT-PCR). The protein expression of Bcl-2 and Bax was determined by Western blotting. MDA levels, NO production, LDH leakage, and SOD as well as caspase-3 activities were also measured using standard methods. Results: Loss of cell viability and excessive cell apoptosis were observed in EA.hy926 cells after 4h of challenge with H2O2 (300μmol/L). However, cell apoptosis was attenuated in different concentrations of TSN IIA (5, 10 and 20μg/μL) pretreated cells. Furthermore, TSN IIA markedly inhibited the elevation of ROS evoked by H2O2. Real time RT-PCR and Western blotting analysis showed that TSN IIA significantly decreased the expressions of pro-apoptotic proteins (Bax and caspase-3) while significantly increased the expression of anti-apoptotic protein Bcl-2, and resulted in obvious reduction of Bax/Bcl-2 ratio in EA.hy926 cells induced by H2O2. Conclusion: These observations provide preliminary evidence that TSN IIA protects EA.hy926 cells against H2O2 damage, which is mainly associated with the ROS generation, followed by the imbalance of the Bax/Bcl-2 ratio, and caspase-3 activation leading to apoptosis. [Copyright &y& Elsevier]