Project description:Dysregulated redox signaling contributes to pulmonary hypertension (PH) and vascular-selective depletion of the redox enzyme EC-SOD (EC-SOD SMC KO) worsens chronic hypoxic PH. Given the important role of macrophages in vascular remodeling and PH, this study aimed to determine if interstitial macrophages (IMs) and their interactions with the extracellular matrix (ECM) component, hyaluronan, are modulated by vascular EC-SOD. Floxed wild-type (WT), EC-SOD SMC KO, and EC-SOD mimetic- or vehicle-treated mice were exposed to hypobaric hypoxia (~10% FiO2), for 4, 14, or 21 days. Using flow cytometry, we demonstrated that the transient increase in IMs at day 4 was exacerbated in EC-SOD SMC KO mice and prevented with EC-SOD mimetic (5 mg/kg, subcutaneous, day 1). Highlighting the importance of targeting vascular oxidative stress in the early response to hypoxia, pretreatment with this single dose of EC-SOD mimetic decreased right ventricular systolic pressure, right ventricular hypertrophy, and small vessel muscularization at day 21. To assess IM phenotypic reprogramming in this model, RNAseq was performed on flow-sorted IMs revealing baseline proinflammatory activation and enhanced activation of vascular and ECM remodeling pathways in response to hypoxia in EC-SOD SMC KO IMs compared to controls. To further investigate the ECM remodeling response, we quantified IMs expressing the hyaluronan receptor Lyve1, and IM-hyaluronan binding. Lyve1+IMs and Lyve1+HA+IMs were increased in response to hypoxia in EC-SOD SMC KO mice and accumulated in the perivascular space. In conclusion, vascular EC-SOD limits IM accumulation and proinflammatory profibrotic IM signaling, including perivascular accumulation of Lyve1+IMs and their binding to hyaluronan.
Project description:Whole-genome profiling of SH-SY5Y cells was done on neuroblastoma SH-SY5Y stably transfected with cDNAs coding for SOD1WT or the mutant SOD1(G93A) protein. Five wt SOD versus five mutant SOD
Project description:We compared gene expression in the small intestine (ileum) of mice that were either (i) germ-free, (ii) colonized with a conventional mouse cecal microbiota, (iii) colonized with a conventional zebrafish gut microbiota, or (iv) colonized with Pseudomonas aeruginosa PAO1. Experiment Overall Design: Adult germ-free NMRI mice were colonized with either (i) a conventional mouse cecal microbiota harvested from adult Swiss-Webster mice (5 biological replicates), (ii) a conventional zebrafish intestinal microbiota harvested from adult C32 zebrafish (3 biological replicates), or (iii) a culture of Pseudomonas aeruginosa PAO1 (5 biological replicates). 14 days after colonization, total RNA was prepared from the ileum of each animal, with total RNA prepared from adult germ-free NMRI mouse ileum serving as negative controls (5 biological replicates). RNA was used as template to generate cRNA for hybridization to Affymetrix 430 v2 Mouse GeneChips.
Project description:A known human SNP in the matrix-binding domain of extracellular superoxide dismutase (EC-SOD), with an arginine to glycine substitution at position 213 (R213G), redistributes EC-SOD from the matrix into extracellular fluids. We reported that, following bleomycin (bleo), knock-in mice harboring the human R213G SNP (R213G mice), compared to wild-type (WT) littermates exhibit enhanced resolution of inflammation and protection against fibrosis. We tested the hypothesis that the EC-SOD R213G SNP promotes resolution via accelerated apoptosis of recruited alveolar macrophage (recAM).
