Role of the C-C chemokine receptor-2 in a murine model of injury-induced osteoarthritis
OSTEOARTHRITIS AND CARTILAGE
Authors: Longobardi, L.; Temple, J. D.; Tagliafierro, L.; Willcockson, H.; Esposito, A.; D'Onofrio, N.; Stein, E.; Li, T.; Myers, T. J.; Ozkan, H.; Balestrieri, M. L.; Ulici, V.; Loeser, R. F.; Spagnoli, A.
Abstract
Objective: We previously found in our embryonic studies that proper regulation of the chemokine CCL12 through its sole receptor CCR2, is critical for joint and growth plate development. In the present study, we examined the role of CCR2 in injury-induced-osteoarthritis (OA). Method: We used a murine model of injury-induced-OA (destabilization of medial meniscus, DMM), and systemically blocked CCR2 using a specific antagonist (RS504393) at different times during disease progression. We examined joint degeneration by assessing cartilage (cartilage loss, chondrocyte hypertrophy, MMP-13 expression) and bone lesions (bone sclerosis, osteophytes formation) with or without the CCR2 antagonist. We also performed pain behavioral studies by assessing the weight distribution between the normal and arthritic hind paws using the IITS incapacitance meter. Results: Testing early vs delayed administration of the CCR2 antagonist demonstrated differential effects on joint damage. We found that OA changes in articular cartilage and bone were ameliorated by pharmacological CCR2 blockade, if given early in OA development: specifically, pharmacological targeting of CCR2 during the first 4 weeks (wks) following injury, reduced OA cartilage and bone damage, with less effectiveness with later treatments. Importantly, our pain-related behavioral studies showed that blockade of CCR2 signaling during early, 1-4 wks post-surgery or moderate, 4-8 wks post-surgery, OA was sufficient to decrease pain measures, with sustained improvement at later stages, after treatment was stopped. Conclusions: Our data highlight the potential efficacy of antagonizing CCR2 at early stages to slow the progression of post-injury OA and, in addition, improve pain symptoms. (C) 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Toxicogenomic analysis of the pulmonary toxic effects of hexanal in F344 rat
ENVIRONMENTAL TOXICOLOGY
Authors: Cho, Yoon; Lim, Jung-hee; Song, Mi-Kyung; Jeong, Seung-Chan; Lee, Kyuhong; Heo, Yongju; Kim, Tae Sung; Ryu, Jae-Chun
Abstract
Hexanal is a major component of indoor air pollutants and is a kind of aldehydes; it has adverse effects on human health. We performed an in vivo inhalation study and transcriptomic analysis to determine the mode of toxic actions in response to hexanal. Fischer 344 rats of both sexes were exposed by inhalation to hexanal aerosol for 4 hday(-1), 5 daysweek(-1) for 4 weeks at 0, 600, 1000, and 1500 ppm. Throughout our microarray-based genome-wide expression analysis, we identified 56 differentially expressed genes in three doses of hexanal; among these genes, 11 genes showed dose-dependent expression patterns (10 downregulated and 1 upregulated, 1.5-fold, p<0.05). Through a comparative toxicogenomics database (CTD) analysis of 11 genes, we determined that five genes (CCL12, DDIT4, KLF2, CEBPD, and ADH6) are linked to diverse disease categories such as cancer, respiratory tract disease, and immune system disease. These diseases were previously known for being induced by volatile organic compounds (VOCs). Our data demonstrated that the hexanal-induced dose-dependent altered genes could be valuable quantitative biomarkers to predict hexanal exposure and to perform relative risk assessments, including pulmonary toxicity. (c) 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 382-396, 2017.