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Chronic endoplasmic reticulum (ER) stress in pancreatic acinar cells has emerged as a major contributor to the recovery of acute pancreatitis (AP). However, the molecular mechanisms linking AP and ER stress remain not fully understood. In this study, we employed caerulein to induce AP-like inflammation in the AR42J rat pancreatic acinar cells to mimic the AP-like acinar cell injury. Caerulein can activate ER stress in AR42J cells, but the molecular link between AP and ER stress remains to be identified. We here reported that translocating chain-associated membrane protein 1 (TRAM1), an ER-resident multispanning membrane protein, was involved in the onset of AP-like injury on AR42J cells. TRAM1 was significantly elevated in caerulein-treated AR42J cells. Furthermore, we showed that knockdown of TRAM1 led to hyperactivation of 78 kDa glucose-regulated protein precursor (GRP78) and C/EBP homologous protein (CHOP) and the activation of downstream apoptosis pathway. Given the fact that the activation of ER stress played a protection role in AP, the pro-inflammatory mediators TNF-α and IL-6 and the marker of cell injury LDH were also analyzed. We found that depletion of TRAM1 markedly increased the secretion of TNF-α, IL-6, and LDH in the cells. Moreover, flow cytometry indicated that treatment with caerulein induced a significant decrease of apoptotic index and increase of necrosis index in TRAM1-siRNA cells, compared with control groups, as indicated by downregulated expression of cleaved caspase-3, caspase-8, and caspase-9 mRNA expression activity in TRAM1-siRNA cells. These data implicated that TRAM1 might protect AR42J cells against caerulein-induced AP in AR42J cells through alleviating ER stress. [ABSTRACT FROM AUTHOR]

Background: Activation of the transcription factor NF-κB and expression of pro-inflammatory mediators have been considered as major events of acute pancreatitis (AP). Karyopherin alpha 2 (KPNA2), a member of the importin α family, reportedly modulates p65 subcellular localization.Aim: This study aimed to investigate the expression and possible functions of KPNA2 in the AP cell and animal model, focusing on its association with NF-κB activation.Methods: An AP cell model was established with the cerulein-stimulated AR42J and isolated rat pancreatic acinar cells. The AP rat model was induced by the intraperitoneal injection of cerulein. The secretion of TNF-α, IL-6, and LDH was detected by ELISA kits and the production of NO using nitric oxide kit. Expression of KPNA2 was measured by RT-PCR and Western blot. Expression levels of IKKα, phosphorylation of p65, and total p65 were detected by Western blot. Co-localization of KPNA2 with p65 was observed by immunofluorescence assay. To determine the biological functions of KPNA2 in cerulein-induced inflammatory response, RNA interference was employed to knockdown KPNA2 expression in AR42J and isolated pancreatic acini cells.Results: Cerulein stimulated KPNA2 expression and IL-6, TNF-α, NO, and LDH production in rat pancreatic acinar cells. Cerulein triggered the phosphorylation and nuclear translocation of NF-κB p65 subunit, indicating the NF-κB activation. The co-localization and nuclear accumulation of KPNA2 and p65 were detected in cerulein-treated cells. Knocking down KPNA2 hindered cerulein-induced nuclear transportation of p65 and alleviated the subsequent inflammatory response in rat pancreatic acinar cells. Additionally, KPNA2 expression was significantly up-regulated in cerulein-induced AP rat model.Conclusions: KPNA2-facilitated p65 nuclear translocation promotes NF-κB activation and inflammation in acute pancreatitis. [ABSTRACT FROM AUTHOR]

Globally, 15.5 million km of land are currently identified as protected areas, which provide society with many ecosystem services including climate-change mitigation. Combining a global database of protected areas, a reconstruction of global land-use history, and a global biogeochemistry model, we estimate that protected areas currently sequester 0.5 Pg C annually, which is about one fifth of the carbon sequestered by all land ecosystems annually. Using an integrated earth systems model to generate climate and land-use scenarios for the twenty-first century, we project that rapid climate change, similar to high-end projections in IPCC's Fifth Assessment Report, would cause the annual carbon sequestration rate in protected areas to drop to about 0.3 Pg C by 2100. For the scenario with both rapid climate change and extensive land-use change driven by population and economic pressures, 5.6 million km of protected areas would be converted to other uses, and carbon sequestration in the remaining protected areas would drop to near zero by 2100. [ABSTRACT FROM AUTHOR]

Objective: Activation of the transcription factor κB (NF-κB) and secretion of pro-inflammatory mediators are major events in acute pancreatitis (AP). Recently, O-linked- N-acetylglucosamine ( O-GlcNAc) modification, one type of posttranslational modifications, reportedly attunes NF-κB function. However, the expression of O-GlcNAc transferase (OGT), the enzyme responsible for O-GlcNAcylation of proteins, in AP, and the possible contribution of OGT-mediated O-GlcNAcylation to the NF-κB inflammatory activation in pancreatic acinar cells and to the AP progression have not been understood. This study focused on the effects and mechanisms of OGT-mediated O-GlcNAcylation during AP. Methods: An AP cell model was established with the caerulein-stimulated AR42 J rat pancreatic acinar cells. The secretion of pro-inflammatory cytokines TNF-α was detected by ELISA kits, and the production of NO was determined using the colorimetric Griess reaction. Expression of OGT was measured by RT-PCR and Western blot. Expression levels of RL2, phosphorylation of p65, total p65, IKKα were detected by Western blot. The NF-κB activity was evaluated by luciferase reporter gene assay. To determine the biological functions of OGT in caerulein-induced inflammatory response, RNA interference and PUGNAc, the inhibitor of O-GlcNAcase (OGA) was employed to regulate OGT expression in AR42 J cells. Results: Caerulein significantly up-regulated the expression of OGT, and increased the global protein O-GlcNAcylation level in AR42 J cells. Reduction of OGT by small interfering RNA (siRNA) inhibited caerulein-triggered inflammation, assessed by the production of pro-inflammatory mediators (TNF-α and NO). We also demonstrated that O-GlcNAcylation directly modified the NF-κB p65 subunit and its upstream activating kinases IKKα in AR42 J cells. Lowering O-GlcNAcylation by OGT knockdown attenuated p65 activating phosphorylation, nuclear translocation, NF-κB transcriptional activity and levels of NF-κB transcriptional targets TNF-α and NO; on the contrary, elevating O-GlcNAc through PUGNAc increased IKKα and p65 O-GlcNAcylation accompanied by increased p65 phosphorylation, activity and levels of TNF-α and NO in caerulein-treated cells. Conclusions: Our results demonstrate for the first time that OGT-mediated O-GlcNAcylation promotes NF-κB signaling activation and inflammation in pancreatic acinar cells, which might promote the progression of AP. [ABSTRACT FROM AUTHOR]

We discuss a strategy for investigating the impacts of climate change on Earth's physical, biological and human resources and links to their socio-economic consequences. As examples, we consider effects on agriculture and human health. Progress requires a careful understanding of the chain of physical changes-global and regional temperature, precipitation, ocean acidification, polar ice melting. We relate those changes to other physical and biological variables that help people understand risks to factors relevant to their daily lives-crop yield, food prices, premature death, flooding or drought events, land use change. Finally, we investigate how societies may adapt, or not, to these changes and how the combination of measures to adapt or to live with losses will affect the economy. Valuation and assessment of market impacts can play an important role, but we must recognize the limits of efforts to value impacts where deep uncertainty does not allow a description of the causal chain of effects that can be described, much less assigned a likelihood. A mixed approach of valuing impacts, evaluating physical and biological effects, and working to better describe uncertainties in the earth system can contribute to the social dialogue needed to achieve consensus on the level and type of mitigation and adaptation actions. [ABSTRACT FROM AUTHOR]