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Objective Calcineurin-binding protein 1 (CABIN-1) regulates calcineurin phosphatase activity as well as the activation, apoptosis, and inflammatory responses of fibroblast-like synoviocytes (FLS), which actively participate in the chronic inflammatory responses in rheumatoid arthritis (RA). However, the mechanism of action of CABIN-1 in FLS apoptosis is not clear. This study was undertaken to define the regulatory role of CABIN-1 in FLS from mice with collagen-induced arthritis (CIA). Methods Transgenic mice overexpressing human CABIN-1 in joint tissue under the control of a type II collagen promoter were generated. Expression of human CABIN-1 (hCABIN-1) in joints and FLS was determined by reverse transcription–polymerase chain reaction (RT-PCR) and Western blot analysis. The expression of cytokines, matrix metalloproteinases (MMPs), and apoptosis-related genes in FLS was determined by enzyme-linked immunosorbent assay, gelatin zymography, and RT-PCR, respectively. Joints were stained with hematoxylin and eosin and with tartrate-resistant acid phosphatase for histologic analysis. Results Human CABIN-1–transgenic mice with CIA had less severe arthritis than wild-type mice with CIA, as assessed according to hind paw thickness and histologic features. The milder arthritis was accompanied by significantly enhanced apoptosis in transgenic mice, evidenced by a significantly greater number of TUNEL-positive cells in synovial tissue. Expression of inflammatory cytokines and MMPs in the transgenic mice with CIA was reduced, and they exhibited decreased Akt activation and increased expression of p53, caspase 3, caspase 9, and Bax. Conclusion Our findings demonstrate that hCABIN-1 plays a critical role in promoting apoptosis of FLS and in attenuating inflammation and cartilage and bone destruction in RA. These results help elucidate the pathogenic mechanisms of RA and suggest that CABIN-1 is a potential target for treatment of this disease.

Oxidative stress such as reactive oxygen species (ROS) within the inflamed joint have been indicated as being involved as inflammatory mediators in the induction of arthritis. Correlations between extracellular- superoxide dismutase (EC-SOD) and inflammatory arthritis have been shown in several animal models of RA. However, there is a question whether the over-expression of EC-SOD on arthritic joint also could suppress the progression of disease or not. In the present study, the effect on the synovial tissue of experimental arthritis was investigated using EC-SOD over-expressing transgenic mice. The over-expression of EC- SOD in joint tissue was confirmed by RT-PCR and immunohistochemistry. The degree of the inflammation in EC-SOD transgenic mice was suppressed in the collagen-induced arthritis model. In a cytokine assay, the production of pro-inflammatory cytokines such as, IL-1β, TNFα, and matrix metalloproteinases (MMPs) was decreased in fibroblast-like synoviocyte (FLS) but not in peripheral blood. Histological examination also showed repressed cartilage destruction and bone in EC-SOD transgenic mice. In conclusion, these data suggest that the over-expression of EC-SOD in FLS contributes to the activation of FLS and protection from joint destruction by depressing the production of the pro-inflammatory cytokines and MMPs. These results provide EC-SOD transgenic mice with a useful animal model for inflammatory arthritis research.

Atopic dermatitis (AD) is a chronically relapsing, noncontagious pruritic skin disease with two phases: acute and chronic. Previous studies have shown that the cysteine protease cathepsin S (CTSS) is linked to inflammatory processes, including atherosclerosis and asthma. The possibility that this or other cysteine proteases might cause itching or be part of a classical ligand–receptor signaling cascade has not been previously considered. Recently, CTSS was shown to be a ligand for proteinase-activated receptor-2 (PAR-2), which is associated with itching. In this study, we show that CTSS-overexpressing transgenic (TG) mice spontaneously develop a skin disorder similar to chronic AD. The results of this study suggest that CTSS overexpression triggers PAR-2 expression in dendritic cells (DCs), resulting in the promotion of CD4+ differentiation, which is involved in major histocompatibility complex (MHC) class II expression. In addition, we investigated mast cells and macrophages and found significantly higher mean levels of T helper type 1 (Th1) cell–associated cytokines than T helper type 2 (Th2) cell–associated cytokines in CTSS-overexpressing TG mice. These results suggest that increased PAR-2 expression in DCs as a result of CTSS overexpression induces scratching behavior and Th1 cell–associated cytokine expression, and can trigger chronic AD symptoms.

The T-cell receptor (TCR) engages with an antigen and initiates a signaling cascade that leads to the activation of transcription factors. Roquin, a protein encoded by the RC3H1 gene and characterized as an immune regulator, was recently identified as a novel RING-type ubiquitin ligase family member, but the mechanisms by which Roquin regulates T-cell responses are unclear. We used the EL-4 murine lymphoma cell line to elucidate the role of Roquin in vitro. Roquin-overexpressing EL-4 cells became hyper-responsive after anti-CD3/CD28 stimulation in vitro and were a major source of the cytokines IL-2 and TNF-α. Upon activation, these cells showed particularly enhanced production of IL-2 and TNF-α. To clarify the important role played by Roquin in T-cell responses ex vivo, we generated T-cell-specific Roquin transgenic (Tg) mice. Roquin-Tg CD4(+) T-cells showed enhanced production of IL-2 and TNF-α in response to TCR stimulation with anti-CD28 co-stimulation. Further studies are necessary to investigate the role of Roquin in the regulation of primary T-cell activation, survival, and differentiation.

Wnt/Wg genes play a critical role in the development of various organisms. For example, the Wnt/beta-catenin signal promotes heart formation and cardiomyocyte differentiation in mice. Previous studies have shown that RGS19 (regulator of G protein signaling 19), which has Galpha subunits with GTPase activity, inhibits the Wnt/beta-catenin signal through inactivation of Galpha(o). In the present study, the effects of RGS19 on mouse cardiac development were observed. In P19 teratocarcinoma cells with RGS19 overexpression, RGS19 inhibited cardiomyocyte differentiation by blocking the Wnt signal. Additionally, several genes targeted by Wnt were down-regulated. For the in vivo study, we generated RGS19-overexpressing transgenic (RGS19 TG) mice. In these transgenic mice, septal defects and thin-walled ventricles were observed during the embryonic phase of development, and the expression of cardiogenesis-related genes, BMP4 and Mef2C, was reduced significantly. RGS19 TG mice showed increased expression levels of brain natriuretic peptide and beta-MHC, which are markers of heart failure, increase of cell proliferation, and electrocardiogram analysis shows abnormal ventricle repolarization. These data provide in vitro and in vivo evidence that RGS19 influenced cardiac development and had negative effects on heart function.

Cachexia-anorexia syndrome, which is called cancer cachexia, is a common and important indicator of cancer and occurs in 30% to 80% of cancer patients. Cancer cachexia is characterized by a severe progressive body wasting, accompanied by loss of adipose tissue and skeletal muscle mass. The presence of cachexia is associated with a worsened prognosis and contributes to up to 20% of cancer deaths. In most cases, cancer cachexia patients clinically show anorexia caused through a complex system of hormones and neuropeptides. To investigate efficacy in development of new medicine, an optimized animal model is essentially required. Although several cancer cachexia animal models have been established, we focused on developing a better animal model particularly for efficacy evaluation with advanced bioimaging evaluation methods. First of all, we confirmed that an appropriate mouse strain is CDF1 in comparison with DBA1 and Balb/c after xenografting of Colon26. As the second step, we checked cell numbers with pattern of tumor growth. In human clinics, cure of cancer cachexia is usually performed with surgical removal of tumor. To make the animal model similar to clinical circumstances, we tested recovery time and pattern after removal of tumor. With optimized mouse model we tested efficacy of anticancer drug Megace 200 mg/kg as a positive control. In addition, we applied advanced bioimaging equipment such as MRI and CT to visualize actual tumor and fat with body composition. We expect that optimized animal model of cancer cachexia will prepare the way for more accurate efficacy test in preclinical state to go to a clinical trial. Citation Format: Jiyeong Bae, Ig Jun Cho, Jung Hyu Shin, Hyung Soo Yuh, Hyung Ho Moon, Hye Lim Lee, Yeong Nang Jo, Yeon Ju Park, Woo Sung Choi, Byung Hwa Hyun. Optimization of a cachexia animal model for efficacy evaluation of candidates [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A017.

The circling (cir/cir) mouse is a murine model for human nonsyndromic deafness DFNB6. Transmembrane inner ear (tmie) is the causative gene and its mutation through deletion of a 40-kilobase genomic region including tmie leads to deafness. The function of Tmie is unknown. To better understand the function of Tmie, we focused on the spatiotemporal expression of tmie in the rat cochlea by using a Tmie-specific antibody. Results showed that tmie expression was prominent in early postnatal rat cochleas in the stereocilia bundles of hair cells. The Tmie signal spread from the stereocilia to the hair cell body region and on to organ of Corti cells. No Tmie signal was observed in cell nuclei; Tmie was localized to the cytoplasm. Because Tmie is predicted to have 1 or 2 transmembrane domains, we postulate that it is localized to membrane-based organelles or the plasma membrane. Our results imply that Tmie exists in the cytoplasm and may have a key role in the maturation and structure of stereocilia bundles in developing hair cells. After hair cell maturation, Tmie is thought to be involved in the maintenance of organ of Corti cells.

The transcription factor Juxtaposed with another zinc finger gene 1 (JAZF1) is a zinc finger protein that binds to the nuclear orphan receptor TR4. Recent evidence indicates that TR4 receptor functions as both a positive and negative regulator of transcription, but the role of JAZF1 in transcriptional mechanisms has not been elucidated. Recently, the incidence rate of congenital heart malformations was reported to be significantly elevated in patients who had neurofibromatosis 1 (NF1) with chromosomal microdeletion syndrome. Furthermore, Joined to JAZF1 (SUZ12) is expressed at high levels in the hearts of adult patients with NF1 microdeletion syndrome. Therefore, we hypothesized that ectopic expression of JAZF1 may lead to cardiac malformations that deleteriously affect the survival of neonates and adults. We sought to elucidate the role of JAZF1 in cardiac development using a Jazf1-overexpressing (Jazf1-Tg) mouse model. In Jazf1-Tg mice, Jazf1 mRNA expression was significantly elevated in the heart. Jazf1-Tg mice also showed cardiac defects, such as high blood pressure, electrocardiogram abnormalities, apoptosis of cardiomyocytes, ventricular non-compaction, and mitochondrial defects. In addition, we found that the expression levels of pro-apoptotic genes were elevated in the hearts of Jazf1-Tg mice. These findings suggest that Jazf1 overexpression may induce heart failure symptoms through the upregulation of pro-apoptotic genes in cardiomyocytes.

The major objective of this study was to improve the development rate of parthenogenetic porcine embryos. In this study, the anti-oxidative and anti-apoptotic effects of three antioxidants, β-mercaptoethanol (β-ME), α-tocopherol, and extracellular superoxide dismutase (EC-SOD), were examined on the development of parthenogenetic porcine embryos. The development rate of parthenogenetic porcine embryos to the blastocyst stage was 8.1% for control; 19.1%, 14.6%, and 5.0% for 1, 3, and 5 μM β-ME; 17.2% and 17.5% for 50 and 100 μM α-tocopherol and 12.0% and 4.0% for EC-SOD transgenic mouse embryonic fibroblast (Tg-MEF) and EC-SOD non-transgenic mouse embryonic fibroblast (NTg-MEF) conditioned medium at day 3, respectively. Here, β-ME, α-tocopherol, and EC-SOD Tg-MEF conditioned medium increased the development rate of parthenogenetic porcine embryos to the blastocyst stage (P < 0.05). The average number of total cells and apoptotic cells at the blastocyst was analyzed at the optimal conditions of the three antioxidants. The three antioxidants increased the average number of total cells at the blastocyst, and they decreased apoptotic cells at the blastocyst as compared to control without supplementation (P < 0.05). When the reactive oxygen species levels in two-cell embryos after 1 μM β-ME and 100 μM α-tocopherol treatment were examined, those were lower than control group (P < 0.05). In conclusion, it was found that the three antioxidants, β-mercaptoethanol, α-tocopherol, and EC-SOD Tg-MEF, conditioned medium can play a role as a strong stimulator in the development of parthenogenetic porcine embryos.