Salmonella Typhimurium impairs glycolysismediated acidification of phagosomes to evade macrophage defense

Regulation of cellular metabolism is now recognized as a crucial mechanism for the activation of innate and adaptive immune cells upon diverse extracellular stimuli. Macrophages, for instance, increase glycolysis upon stimulation with pathogen-associated molecular patterns (PAMPs). Conceivably, pathogens also counteract these metabolic changes for their own survival in the host. Despite this dynamic interplay in host-pathogen interactions, the role of immunometabolism in the context of intracellular bacterial infections is still unclear. Here, employing unbiased metabolomic and transcriptomic approaches, we investigated the role of metabolic adaptations of macrophages upon Salmonella enterica serovar Typhimurium (S. Typhimurium) infections. Importantly, our results suggest that S. Typhimurium abrogates glycolysis and its modulators such as insulin-signaling to impair macrophage defense. Mechanistically, glycolysis facilitates glycolytic enzyme aldolase A mediated v- ATPase assembly and the acidification of phagosomes which is critical for lysosomal degradation. Thus, impairment in the glycolytic machinery eventually leads to decreased bacterial clearance and antigen presentation in murine macrophages (BMDM). Collectively, our results highlight a vital molecular link between metabolic adaptation and phagosome maturation in macrophages, which is targeted by S. Typhimurium to evade cell-autonomous defense. Copyright

Green decisions: The role of environmental strategies and proactivity in India’s manufacturing micro enterprises

This study investigates the implication of environmental strategies and environmental management accounting (EMA) on the environmental performance of manufacturing micro companies in India. It also assesses the mediating influence of EMA and the moderating impact of environmental proactivity. This paper employs the natural resource-based view theory to evaluate the domination of environmental strategies and EMA on environmental effectiveness. Even though MSMEs play a significant role in the Indian economy, their environmental impact is considerable due to less stringent adherence to environmental standards and practices. The data were gathered via a survey administered to managers of MSMEs. In the analysis, 107 reliable responses were included. Partial least square structural equation modeling is employed for the analysis of the dataset. The results show that environmental strategies positively influence environmental performance and EMA. EMA operates as a mediator for environmental strategies and environmental outcomes. Moreover, environmental proactivity moderates the association between environmental strategies and environmental performance. Hypotheses testing results conclude that manufacturing micro companies that emphasize environmental strategies and factors have improved environmental performance. Companies that proactively deal with environmental issues develop strategies to achieve sustainability

Efficacy and Safety of Ticagrelor Monotherapy in Patients Undergoing Percutaneous Coronary Intervention: A Meta-Analysis

Dual antiplatelet therapy (DAPT) and subsequent P2Y12 inhibitor monotherapy, particularly ticagrelor, is an emerging treatment strategy in patients undergoing percutaneous coronary intervention (PCI). This meta-analysis was designed to investigate whether short-term DAPT followed by ticagrelor monotherapy is associated with a favorable outcome as compared with standard DAPT (1–3 months of DAPT was termed “short-term” DAPT, 6–12 months DAPT was termed “standard” DAPT). The primary outcome was the composite of major adverse cardiovascular events (MACE) comprising myocardial infarction, stroke, and cardiovascular death. Secondary outcomes included all-cause mortality and net adverse clinical events (NACE; myocardial infarction, stroke, all-cause death, stent thrombosis, and major bleeding). The primary safety outcome was major bleeding. Three studies comprising 26,143 patients were included. The risk of MACE was similar between the two treatment groups (risk ratio (RR) 0.86, 95% confidence interval (CI), 0.72–1.02, P = 0.08, I2 = 22%). Short-term DAPT followed by ticagrelor monotherapy resulted in a 20% relative risk reduction of all-cause mortality (RR 0.80, 95% CI, 0.65–0.98, P = 0.03, I2 = 0%) and an 18% relative risk reduction of NACE (RR 0.82, 95% CI, 0.71–0.94, P = 0.005, I2 = 33%) as compared with standard DAPT. Short-term DAPT followed by ticagrelor monotherapy significantly decreased the risk of major bleeding (RR 0.67, 95% CI, 0.49–0.92, P = 0.01, I2 = 65%). In patients with acute coronary syndrome, short-term DAPT followed by ticagrelor monotherapy resulted in an unchanged ischemic risk but a significantly lower bleeding risk compared with standard DAPT. Short-term DAPT followed by ticagrelor monotherapy compared with standard DAPT resulted in a favorable safety and efficacy profile. Direct comparisons of aspirin vs. ticagrelor monotherapy following PCI are needed

Host-Microbe Co-metabolism Dictates Cancer Drug Efficacy in C. elegans

Fluoropyrimidines are the first-line treatment for colorectal cancer, but their efficacy is highly variable between patients. We queried whether gut microbes, a known source of inter-individual variability, impacted drug efficacy. Combining two tractable genetic models, the bacterium E. coli and the nematode C. elegans, we performed three-way high-throughput screens that unraveled the complexity underlying host-microbe-drug interactions. We report that microbes can bolster or suppress the effects of fluoropyrimidines through metabolic drug interconversion involving bacterial vitamin B-6, B-9, and ribonucleotide metabolism. Also, disturbances in bacterial deoxynucleotide pools amplify 5-FU-induced autophagy and cell death in host cells, an effect regulated by the nucleoside diphosphate kinase ndk-1. Our data suggest a two-way bacterial mediation of fluoropyrimidine effects on host metabolism, which contributes to drug efficacy. These findings highlight the potential therapeutic power of manipulating intestinal microbiota to ensure host metabolic health and treat disease.Peer reviewe

Host-Microbe Co-metabolism Dictates Cancer Drug Efficacy in C. elegans.

Fluoropyrimidines are the first-line treatment for colorectal cancer, but their efficacy is highly variable between patients. We queried whether gut microbes, a known source of inter-individual variability, impacted drug efficacy. Combining two tractable genetic models, the bacterium E. coli and the nematode C. elegans, we performed three-way high-throughput screens that unraveled the complexity underlying host-microbe-drug interactions. We report that microbes can bolster or suppress the effects of fluoropyrimidines through metabolic drug interconversion involving bacterial vitamin B6, B9, and ribonucleotide metabolism. Also, disturbances in bacterial deoxynucleotide pools amplify 5-FU-induced autophagy and cell death in host cells, an effect regulated by the nucleoside diphosphate kinase ndk-1. Our data suggest a two-way bacterial mediation of fluoropyrimidine effects on host metabolism, which contributes to drug efficacy. These findings highlight the potential therapeutic power of manipulating intestinal microbiota to ensure host metabolic health and treat disease

KLF15 Is a Molecular Link between Endoplasmic Reticulum Stress and Insulin Resistance

Obesity places major demands on the protein folding capacity of the endoplasmic reticulum (ER), resulting in ER stress, a condition that promotes hepatic insulin resistance and steatosis. Here we identify the transcription factor, Kruppel-like factor 15 (KLF15), as an essential mediator of ER stress-induced insulin resistance in the liver. Mice with a targeted deletion of KLF15 exhibit increased hepatic ER stress, inflammation, and JNK activation compared to WT mice; however, KLF15-/- mice are protected against hepatic insulin resistance and fatty liver under high-fat feeding conditions and in response to pharmacological induction of ER stress. The mammalian target of rapamycin complex 1 (mTORC1), a key regulator of cellular energy homeostasis, has been shown to cooperate with ER stress signaling pathways to promote hepatic insulin resistance and lipid accumulation. We find that the uncoupling of ER stress and insulin resistance in KLF15-/- liver is associated with the maintenance of a low energy state characterized by decreased mTORC1 activity, increased AMPK phosphorylation and PGC-1α expression and activation of autophagy, an intracellular degradation process that enhances hepatic insulin sensitivity. Furthermore, in primary hepatocytes, KLF15 deficiency markedly inhibits activation of mTORC1 by amino acids and insulin, suggesting a mechanism by which KLF15 controls mTORC1-mediated insulin resistance. This study establishes KLF15 as an important molecular link between ER stress and insulin action

Automated Analysis of Cryptococcal Macrophage Parasitism Using GFP-Tagged Cryptococci

The human fungal pathogens Cryptococcus neoformans and C. gattii cause life-threatening infections of the central nervous system. One of the major characteristics of cryptococcal disease is the ability of the pathogen to parasitise upon phagocytic immune effector cells, a phenomenon that correlates strongly with virulence in rodent models of infection. Despite the importance of phagocyte/Cryptococcus interactions to disease progression, current methods for assaying virulence in the acrophage system are both time consuming and low throughput. Here, we introduce the first stable and fully characterised GFP–expressing derivatives of two widely used cryptococcal strains: C. neoformans serotype A type strain H99 and C. gattii serotype B type strain R265. Both strains show unaltered responses to environmental and host stress conditions and no deficiency in virulence in the macrophage model system. In addition, we report the development of a method to effectively and rapidly investigate macrophage parasitism by flow cytometry, a technique that preserves the accuracy of current approaches but offers a four-fold improvement in speed

Antimalarial drug artemether inhibits neuroinflammation in BV2 microglia through Nrf2-dependent mechanisms

Artemether, a lipid-soluble derivative of artemisinin has been reported to possess anti-inflammatory properties. In this study, we have investigated the molecular mechanisms involved in the inhibition of neuroinflammation by the drug. The effects of artemether on neuroinflammation-mediated HT22 neuronal toxicity were also investigated in a BV2 microglia/HT22 neuron co-culture. To investigate effects on neuroinflammation, we used LPS-stimulated BV2 microglia treated with artemether (5-40µM) for 24 hours. ELISAs and western blotting were used to detect pro inflammatory cytokines, nitric oxide, PGE2, iNOS, COX-2 and mPGES-1. BACE-1 activity and Aβ levels were measured with ELISA kits. Protein levels of targets in NF-kappaB and p38 MAPK signalling, as well as HO-1, NQO1 and Nrf2 were also measured with western blot. NF-kappaB binding to the DNA was investigated using EMSA. MTT, DNA fragmentation and ROS assays in BV2-HT22 neuronal co-culture were used to evaluate the effects of artemether on neuroinflammation-induced neuronal death. The role of Nrf2 in the anti-inflammatory activity of artemether was investigated in BV2 cells transfected with Nrf2 siRNA. Artemether significantly suppressed pro-inflammatory mediators (NO/iNOS, PGE2/COX-2/mPGES-1, TNFα, and IL-6), Aβ and BACE-1 in BV2 cells following LPS stimulation. These effects of artemether were shown to be mediated through inhibition of NF-kappaB and p38MAPK signalling. Artemether produced increased levels of HO-1, NQO1 and GSH in BV2 microglia. The drug activated Nrf2 activity by increasing nuclear translocation of Nrf2 and its binding to antioxidant response elements in BV2 cells. Transfection of BV2 microglia with Nrf2 siRNA resulted in the loss of both anti-inflammatory and neuroprotective activities of artemether. We conclude that artemether induces Nrf2 expression and suggest that Nrf2 mediates the anti-inflammatory effect of artemether in BV2 microglia. Our results suggest that this drug has a therapeutic potential in neurodegenerative disorders

Sex differences in clinical profile and outcome after percutaneous coronary intervention for chronic total occlusion.

BACKGROUND: There are limited data around sex differences in the risk profile, treatments and outcomes of percutaneous coronary intervention (PCI) in chronic total occlusion (CTO) lesions in contemporary interventional practice. We investigated the impact of sex on clinical and procedural characteristics, complications and clinical outcomes in a national cohort. METHODS & RESULTS: We created a longitudinal cohort (2006-2018, n = 30,605) of patients with stable angina who underwent CTO PCI in the British Cardiovascular Intervention Society (BCIS) database. Clinical, demographic, procedural and outcome data were analysed in two groups stratified by sex: male (n = 24,651), female (n = 5954). Female patients were older (68 vs 64 years, P < 0.001), had higher prevalence of diabetes mellitus (DM), hypertension (HTN) and prior stroke. Utilization of intravascular ultrasound (IVUS), drug eluting stents (DES), radial or dual access and enabling strategies during CTO PCI were higher in male compared to female patients. Following multivariable analysis, there was no significant difference in in-patient mortality (adjusted odds ratio (OR):1.40, 95 % CI: 0.75-2.61, P = 0.29) and major cardiovascular and cerebrovascular events (MACCE) (adjusted OR: 1.01, 95 % CI: 0.78-1.29, P = 0.96). The crude and adjusted rates of procedural complications (adjusted OR: 1.37, 95 % CI: 1.23-1.52, P < 0.001), coronary artery perforation (adjusted OR: 1.60, 95 % CI: 1.26-2.04, P < 0.001) and major bleeding (adjusted OR: 2.06, 95 % CI: 1.62-2.61, P < 0.001) were higher in women compared with men. CONCLUSION: Female patients treated by CTO PCI were older, underwent lesser complex procedures, but had higher adjusted risk of procedural complications with a similar adjusted risk of mortality and MACCE compared with male patients