Project description:We used 10X Genomic and NextSeq sequencer to identify dysregulated genes in single cell suspension isolated from lungs of SEB-induced ARDS mice treated with vehicle or THC.
Project description:Increased availability of cannabis and cannabinoid-containing products necessitates the need for understanding how exposure to these compounds can affect development. Using cannabinoid receptor-null zebrafish (cnr1-/- and cnr2-/-), we conducted experiments to assess the roles of these receptors in ∆9-tetrahydrocannabinol (THC) and cannabidiol (CBD) developmental and behavioral toxicity. THC increased mortality and deformities (pericardial and yolk sac edemas, a reduction in size) in cnr1-/- and cnr2-/- fish. Conversely, CBD-induced malformations and mortality were significantly reduced in the cnr1-/- and cnr2-/- larvae. THC and CBD exposure caused significantly decreased larval behavior (96 hpf), however, decreased distance travelled was protected in the cnr1-/- and cnr2-/- fish, suggesting these receptors are responsible for mediating behavioral toxicity. Transcriptomic profiling in cnr+/+ embryos developmentally exposed to 4 μM THC or 0.5 μM CBD revealed that a significant portion of differentially expressed genes were targets of PPARγ, a predicted upstream regulator. In Cnr-positive embryos, co-exposure to the PPARγ inhibitor GW9662 and THC or CBD, there was increased toxicity compared to exposure with THC or CBD alone. Co-treatment in the cnr2-/- fish with GW9662 did not alter the CBD-induced decrease in activity. However, co-treatment with GW9662 did remove the protective effect observed in cnr1-/- fish treated to CBD alone. Collectively, these results indicate that PPARγ, Cnr1, and Cnr2 all play crucial roles in the developmental toxicity of THC and CBD.
Project description:Acute Respiratory Distress Syndrome (ARDS) continues to have a high mortality. The objective of this study is to understand the differences in disease biology between survivors and non-survivors by characterizing BALF protein expression profiles in individual ARDS subjects.
Project description:Rat primary astrocytes- were treated with vehicle or delta-9-tetrahydrocannabinol (THC), total RNA was isolated and gene expression in response to THC treatment was studied.
Project description:SARS-CoV-2 is a novel coronavirus that causes acute respiratory distress syndrome (ARDS), death and long-term sequelae. Innate immune cells are critical for host defense but are also the primary drivers of ARDS. The relationships between innate cellular responses in ARDS resulting from COVID-19 compared to other causes of ARDS, such as bacterial sepsis is unclear. Moreover, the beneficial effects of dexamethasone therapy during severe COVID-19 remain speculative, but understanding the mechanistic effects could improve evidence-based therapeutic interventions. To interrogate these relationships, we developed an scRNAseq atlas that is freely accessible (biernaskielab.ca/COVID_neutrophil). We discovered that compared to bacterial ARDS, COVID-19 was associated with distinct neutrophil polarization characterized by either interferon (IFN) or prostaglandin (PG) active states. Neutrophils from bacterial ARDS had higher expression of antibacterial molecules such as PLAC8 and CD83. Dexamethasone therapy in COVID patients rapidly altered the IFNactive state, downregulated interferon responsive genes, and activated IL1R2+ve neutrophils. Dexamethasone also induced the emergence of immature neutrophils expressing immunosuppressive molecules ARG1 and ANXA1, which were not present in healthy controls. Moreover, dexamethasone remodeled global cellular interactions by changing neutrophils from information receivers into information providers. Importantly, male patients had higher proportions of IFNactive neutrophils and a greater degree of steroid-induced immature neutrophil expansion. Indeed, the highest proportion of IFNactive neutrophils was associated with mortality. These results define neutrophil states unique to COVID-19 when contextualized to other life-threatening infections, thereby enhancing the relevance of our findings at the bedside. Furthermore, the molecular benefits of dexamethasone therapy are also defined. The identified molecular pathways can now be targeted to develop improved therapeutics.
Project description:Rat model of ARDS was induced by saline lavage and mechanical ventilation. miRNA from rat lungs were used for dual color DNA microarray hybridization with 3DNA 50 kit version 2. Two-condition experiment, CON vs. ARDS lung tissues. replicates: 6 control, 6 ARDS. One replicate per array.
Project description:Rat model of ARDS was induced by saline lavage and mechanical ventilation. Total RNA from rat lungs were used for dual color DNA microarray hybridization with 3DNA 50 kit version 2. Two-condition experiment, CON vs. ARDS lung tissues. replicates: 5 control, 7 ARDS. One replicate per array.
Project description:Acute respiratory distress syndrome (ARDS) is a severe critical condition with a high mortality that is currently in focus given that it is associated with mortality caused by coronavirus induced disease 2019 (COVID-19). Neutrophils play a key role in the lung injury characteristic of non-COVID-19 ARDS and there is also accumulating evidence of neutrophil mediated lung injury in patients who succumb to infection with SARS-CoV-2. We undertook a functional proteomic and metabolomic survey of circulating neutrophil populations, comparing patients with COVID-19 ARDS and non-COVID-19 ARDS to understand the molecular basis of neutrophil dysregulation. Expansion of the circulating neutrophil compartment and the presence of activated low and normal density mature and immature neutrophil populations occurs in ARDS, irrespective of cause. Release of neutrophil granule proteins, neutrophil activation of the clotting cascade and upregulation of the Mac-1 platelet binding complex with formation of neutrophil platelet aggregates is exaggerated in COVID-19 ARDS. Importantly, activation of components of the neutrophil type I interferon responses is seen in ARDS following infection with SARS-CoV-2, with associated rewiring of neutrophil metabolism to promote glutamine utilisation, and the upregulation of antigen processing and presentation. Whilst dexamethasone treatment constricts the immature low density neutrophil population it does not impact upon prothrombotic hyperinflammatory neutrophil signatures.