Obesity-associated inflammation is characterized by macrophage infiltration into peripheral tissues, contributing to the progression of prediabetes and type 2 diabetes (T2D). The enzyme 12-lipoxygenase (12-LOX) catalyzes the formation of pro-inflammatory eicosanoids and is known to promote the migration of macrophages, yet its role in obesity-associated inflammation remains incompletely understood. Furthermore, differences between mouse and human orthologs of 12-LOX have limited efforts to study existing pharmacologic inhibitors of 12-LOX. In this study, we utilized a human gene replacement mouse model in which the gene encoding mouse 12-LOX (Alox15) is replaced by the human ALOX12 gene. As a model of obesity and dysglycemia, we administered these mice a high-fat diet. We subsequently investigated the effects of VLX-1005, a potent and selective small molecule inhibitor of human 12-LOX. Oral administration of VLX-1005 resulted in improved glucose homeostasis, decreased β cell dedifferentiation, and reduced macrophage infiltration in islets and adipose tissue. Analysis of the stromal vascular fraction from adipose tissue showed a reduction in myeloid cells and cytokine expression with VLX-1005 treatment, indicating decreased adipose tissue inflammation. In a distinct mouse model in which Alox15 was selectively deleted in myeloid cells, we observed decreased β cell dedifferentiation and reduced macrophage infiltration in both islets and adipose tissue, suggesting that the effects of VLX-1005 may relate to the inhibition of 12-LOX in macrophages. These findings highlight 12-LOX as a key factor in obesity-associated inflammation and suggest that 12-LOX inhibition could serve as a therapeutic strategy to improve glucose homeostasis and peripheral inflammation in the setting of obesity and T2D.
Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of insulin-producing pancreatic β-cells. Macrophages infiltrate islets early in T1D pathogenesis, preceding the influx of T- and B-lymphocytes. The integrated stress response (ISR), a cellular pathway activated during stress, coordinates adaptive changes in gene expression to maintain cell function and survival. To study the ISR in macrophages, bone-marrow-derived macrophages were treated with a pharmacological inhibitor of the ISR (ISRIB) and polarized to a proinflammatory M1-like state. We observed a reduction in the number of proinflammatory macrophages, as well as a decrease in iNOS mRNA and protein levels, following ISRIB treatment. RNA-sequencing revealed a reduction in pathways related to stress responses, including ER stress, reactive oxygen species (ROS) regulation, and autophagy, as well as migration pathway genes. ISRIB treatment led to decreased macrophage migration after stimulation in vitro and reduced migration of macrophages to the site of injury after tailfin injury in zebrafish in vivo. Interestingly, ISRIB mediated reduction of M1-like macrophages and reduction of migration was recapitulated by the inhibition of PKR but not PERK, both upstream ISR kinases, highlighting PKR as a key mediator of the ISR in macrophages. Pre-diabetic female non-obese diabetic (NOD) mice administered ISRIB demonstrated an overall reduction in the macrophage numbers in the pancreatic islets. Additionally, the insulitic area of pancreata from ISRIB treated NOD mice had increased PD-L1 levels. PD-L1 protein but not mRNA levels were increased in M1-like macrophages after ISR and PKR inhibition. Our findings identify the ISR, particularly via PKR, as a critical regulator of macrophage driven inflammation and migration in T1D. Our study offers new insights into ISR signaling in macrophages, demonstrating that the ISR may serve as a potential target for intervention in macrophages during early T1D pathogenesis.
Study Objectives:Stroke can result in or exacerbate various sleep disorders. The presence of behaviors such as daytime sleepiness poststroke can indicate underlying sleep disorders which can significantly impact functional recovery and thus require prompt detection and monitoring for improved care. Actigraphy, a quantitative measurement technology, has been primarily validated for nighttime sleep in healthy adults; however, its validity for daytime sleep monitoring is currently unknown. Therefore this study aims to identify the best-performing actigraphy sensor and algorithm for detecting daytime sleep in poststroke individuals. Methods:Participants wore Actiwatch Spectrum and ActiGraph wGT3X-BT on their less-affected wrist, while trained observers recorded daytime sleep occurrences and activity levels (active, sedentary, and asleep) during non-therapy times. Algorithms, Actiwatch (Autoscore AMRI) and ActiGraph (Cole-Kripke, Sadeh), were compared with on-site observations and assessed using F2 scores, emphasizing sensitivity to detect daytime sleep. Results:Twenty-seven participants from an inpatient stroke rehabilitation unit contributed 173.5 hours of data. The ActiGraph Cole-Kripke algorithm (minute sleep time = 15 minutes, bedtime = 10 minutes, and wake time = 10 minutes) achieved the highest F2 score (0.59). Notably, when participants were in bed, the ActiGraph Cole-Kripke algorithm continued to outperform Sadeh and Actiwatch AMRI, with an F2 score of 0.69. Conclusions:The study demonstrates both Actiwatch and ActiGraph's ability to detect daytime sleep, particularly during bed rest. ActiGraph (Cole-Kripke) algorithm exhibited a more balanced sleep detection profile and higher F2 scores compared to Actiwatch, offering valuable insights for optimizing daytime sleep monitoring with actigraphy in stroke patients.
Type 1 diabetes (T1D) is characterized by the autoimmune destruction of insulin-producing β cells and involves an interplay between β cells and cells of the innate and adaptive immune systems. We investigated the therapeutic potential of targeting 12-lipoxygenase (12-LOX), an enzyme implicated in inflammatory pathways in β cells and macrophages, using a mouse model in which the endogenous mouse Alox15 gene is replaced by the human ALOX12 gene. Our finding demonstrated that VLX-1005, a potent 12-LOX inhibitor, effectively delayed the onset of autoimmune diabetes in human gene replacement non-obese diabetic mice. By spatial proteomics analysis, VLX-1005 treatment resulted in marked reductions in infiltrating T and B cells and macrophages, with accompanying increases in immune checkpoint molecule PD-L1, suggesting a shift toward an immunosuppressive microenvironment. RNA sequencing analysis of isolated islets and polarized proinflammatory macrophages revealed significant alteration of cytokine-responsive pathways and a reduction in IFN response after VLX-1005 treatment. Our studies demonstrated that the ALOX12 human replacement gene mouse provides a platform for the preclinical evaluation of LOX inhibitors and supports VLX-1005 as an inhibitor of human 12-LOX that engages the enzymatic target and alters the inflammatory phenotypes of islets and macrophages to promote the delay of autoimmune diabetes.
ABSTRACT Preventing the onset of autoimmune type 1 diabetes (T1D) is feasible through pharmacological interventions that target molecular stress-responsive mechanisms. Cellular stresses, such as nutrient deficiency, viral infection, or unfolded proteins, trigger the integrated stress response (ISR), which curtails protein synthesis by phosphorylating eIF2α. In T1D, maladaptive unfolded protein response (UPR) in insulin-producing β cells renders these cells susceptible to autoimmunity. We show that inhibition of the eIF2α kinase PERK, a common component of the UPR and ISR, reverses the mRNA translation block in stressed human islets and delays the onset of diabetes, reduces islet inflammation, and preserves β cell mass in T1D-susceptible mice. Single-cell RNA sequencing of islets from PERK-inhibited mice shows reductions in the UPR and PERK signaling pathways and alterations in antigen processing and presentation pathways in β cells. Spatial proteomics of islets from these mice shows an increase in the immune checkpoint protein PD-L1 in β cells. Golgi membrane protein 1, whose levels increase following PERK inhibition in human islets and EndoC-βH1 human β cells, interacts with and stabilizes PD-L1. Collectively, our studies show that PERK activity enhances β cell immunogenicity, and inhibition of PERK may offer a strategy to prevent or delay the development of T1D.
Information technology developments have combined traditional face-to-face counseling with online- or cyber-counseling. As digital natives, Generation Z has easy access to cyber-counseling. However, their attitudes toward cyber-counseling remain unknown. This study explored these attitudes and relevant influencing factors among 1216 Chinese adolescents using self-report questionnaires. Descriptive analyses and structural equation modeling were used for data analysis. The model explained 27.7 % of the total variance, attitudes toward psychological help was the most influential, followed by attitudes toward the Internet and perceived behavioral control. The model was effective in explaining attitudes toward cyber-counseling, emphasizing the influence of attitudes toward psychological help.
Nationwide mass social unrest has emerged in the US since May 25 and raised broad concerns about its impacts on the local COVID-19 epidemics. We compared the COVID-19 transmissibility between May 19–May 25 and May 29–June 4 for each state of the US. We found that social unrest is likely associated with the rebound of the COVID-19 transmissibility, which might raise difficulties in the pandemic control.