Table 1.
Microscopic findings in lungs and heart of rats treated with NIBR-0213.
Incidence (%) and mean severity (GRADES: 1 = minimal/very few and small; 2 = slight/few/small; 3 = moderate/moderate number and size; 4 = marked/many/large) of the microscopic findings in lungs and heart of rats treated with NIBR-0213. The individual severity GRADES are presented in S4 Table.
Fig 1.
Inhibitory efficacy of NIBR-0213 in a rat AiA model.
Inhibition of paw swelling (as measured at day 12 post-adjuvant challenge) in the rat AiA model in response to oral treatments with NIBR-0213 (30 mg/kg BID, n = 10/group) or FTY720 (0.1 mg/kg QD, n = 5/group), starting at either 5 or 9 days post-challenge with Freund Adjuvant. Individual mean mØ and ΔmØ values are presented in S1 Table.
Fig 2.
Impacts of NIBR-0213 on vascular permeability in tissues.
Evans Blue Dye (EBD) leakage measured in various organs at 6 hrs post-oral treatments with, A- NIBR-0213 (10 or 30 mg/kg; n = 3–5 each), B- FTY720 (0.1 or 0.3 mg/kg; n = 3 each). Results are expressed as mean ± s.e.m. fold increase vs respective vehicle controls. The individual EBD measurements are presented in S2 Table. C- Dose-dependent changes in lung pleural fluid measured in rats at 6 hrs post-oral treatments with NIBR-0213 (n = 4–6, each). * p<0.05.
Fig 3.
NIBR-0213-induced vascular leakage in the lungs evaluated by MRI.
(A) Axial MRI sections through the chest of one animal at approximately the same anatomical location acquired before (baseline) and at different time points with respect to beginning of treatment with NIBR-0213 (30 mg/kg BID). The white and red arrows display fluid signals in the lungs and the pleura, respectively, elicited by the compound. (B) Differential MRI signal volumes (mean ± s.e.m; n = 4–8) in the lungs and pleura. For the lungs, differential volumes (i.e. baseline-subtracted) are presented. (C) MRI signals (means ± s.e.m, n = 3) in the lungs and pleura at 24 h and 96 h after beginning of treatment with NIBR-0213 (3, 10 or 30 mg/kg BID) or FTY720 (1 mg/kg QD). For the lungs, differential signal volumes (i.e. baseline-subtracted) are presented. * p<0.05.
Fig 4.
Impacts of NIBR-0213 on lung functions.
Whole body plethysmography of male rats treated orally with NIBR-0213 at 300 mg/kg QD, or its vehicle, for 24 hrs (n = 5 each). * p<0.05.
Fig 5.
Macroscopic changes provoked by NIBR-0213 treatments in rats.
Changes in bodyweight (A) and organ weight (B) of rats (males or females) treated orally with NIBR-0213 at 30, 100 or 300 mg/kg QD, or its vehicle, during 2 weeks. The mean body and organ weights measured in each groups at termination are presented in S3 Table. Results are mean ± s.e.m. (n = 4–5/group/sex). * p<0.05.
Fig 6.
Acute microscopic changes provoked by NIBR-0213 in rat lungs.
An overview of acute inflammatory changes (A: 4X, H&E) and of perivascular/alveolar/interstitial edema (B: 8X, H&E) observed in the lungs of rats treated orally over 2 week with NIBR-0213 at 100 or 300 mg/kg QD, respectively.
Fig 7.
Chronic microscopic changes provoked by NIBR-0213 in rat lungs.
An overview of chronic changes with alveolar degeneration /regeneration and accumulation of macrophages (A: 10X, H&E.) and of fibrotic foci (B: 12X, H&E.) observed in the lungs of a rat treated orally over 2 weeks with NIBR-0213 at 300 and 100 mg/kg QD, respectively.
Fig 8.
Acute microscopic changes provoked by NIBR-0213 in rat hearts.
Perivascular edema (A: 20X, H&E.) and focal degenerative myocytes with interstitial inflammatory cells and fibrosis (B: 20X, H&E.) observed in the hearts of a rat treated orally over 2 weeks with NIBR-0213 at 100 mg/kg QD.