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Purpose: The role of fibroblast growth factor (FGF) in orbital fibroblasts (OFs) is rarely known. In this study, we investigated the effect of FGF10 on fibrosis and the inflammation mechanism of Graves′ orbitopathy (GO). Methods: Orbital tissue from GO (n = 15) and non-GO (n = 15) was obtained for this study. The mRNA and protein expression levels of FGF10 and FGF receptor 2b (FGFR2b) in orbital tissue were determined by real-time polymerase chain reaction, western blot analysis, and confocal microscopy. The effects of FGF10 on transforming growth factor (TGF)-β1 induced fibrotic proteins and interleukin (IL)-1β- or tumor necrosis factor (TNF)-α- induced inflammatory proteins were investigated using recombinant human (rh) FGF10 and small interfering (si) RNA transfection against FGF10. Results: FGF10 and FGFR2b mRNA expression levels were significantly lower in GO orbital tissues than in non-GO orbital tissues (p = 0.009 and 0.005, respectively). Immunostaining of FGF10 in orbital adipose tissues showed differences in FGF10 expression between GO and control samples. Immunostaining of FGF10 was very weak in the orbital tissues of GO patients. TGF-β1-induced fibronectin, collagen Iα, α-smooth muscle actin protein expression in GO OFs was attenuated by rhFGF10 treatment and increased by knockdown of FGF10 via siFGF10 transfection. Similarly, IL-1β- or TNF-α-induced IL-6, IL-8, and cyclooxygenase-2 protein production in GO OFs was either blocked by rhFGF10 treatment or further upregulated by inhibition of FGF10 via siFGF10 transfection. Conclusions: Our data demonstrate that FGF10 has beneficial effects on the inflammatory and fibrotic mechanisms of GO in primary cultured OFs, providing new insights into GO pathology and the discovery of FGF10 as a promising novel therapeutic application for the treatment of GO. [ABSTRACT FROM AUTHOR]

Graves' orbitopathy (GO) is characterised in early stages by orbital fibroblast inflammation, which can be aggravated by oxidative stress and often leads to fibrosis. Protein tyrosine protein 1B (PTP1B) is a regulator of inflammation and a therapeutic target in diabetes. We investigated the role of PTP1B in the GO mechanism using orbital fibroblasts from GO and healthy non-GO subjects. After 24 hours of transfection with PTPN1 siRNA, the fibroblasts were exposed to interleukin (IL)-1β, cigarette smoke extract (CSE), H2O2, and transforming growth factor (TGF)-β stimulations. Inflammatory cytokines and fibrosis-related proteins were analysed using western blotting and/or enzyme-linked immunosorbent assay (ELISA). Reactive oxygen species (ROS) release was detected using an oxidant-sensitive fluorescent probe. IL-1β, tumor necrosis factor (TNF)-α, bovine thyroid stimulating hormone (bTSH), high-affinity human stimulatory monoclonal antibody of TSH receptor (M22), and insulin-like growth factor-1 (IGF-1) significantly increased PTP1B protein production in GO and non-GO fibroblasts. PTPN1 silencing significantly blocked IL-1β-induced inflammatory cytokine production, CSE- and H2O2-induced ROS synthesis, and TGF-β-induced expression of collagen Iα, α-smooth muscle actin (SMA), and fibronectin in GO fibroblasts. Silencing PTPN1 also decreased phosphorylation levels of Akt, p38, and c-Jun N-terminal kinase (JNK) and endoplasmic reticulum (ER)-stress response proteins in GO cells. PTP1B may be a potential therapeutic target of anti-inflammatory, anti-oxidant and anti-fibrotic treatment of GO. [ABSTRACT FROM AUTHOR]

Background: To investigate the role of microRNA (miR)-27a and miR-27b in adipogenesis in an in vitro model of Graves’ orbitopathy (GO). Methods: Orbital fat tissues were harvested from GO and non-GO participants for primary orbital fibroblast cultures. The expression levels of miR-27a and miR-27b between GO and non-GO orbital fat tissues were compared. During adipogenesis of GO orbital fibroblasts, the expression levels of miR-27a and miR-27b were determined, and the effects of mimics of miR-27a and miR-27b transfection on adipogenesis of GO orbital fibroblast were investigated. Results: Real time-polymerase chain reaction showed significantly more decreases in miR-27a and miR-27b levels in orbital fat tissues in GO participants than in non-GO participants (p < 0.05). The expression of both miR-27a and miR-27b was highest in orbital fibroblasts at day 0 and declined gradually after the induction of adipogenic differentiation. The expression levels of PPARγ, CCAAT/enhancer binding protein (C/EBP)α and C/EBPβ were decreased and Oil Red O-stained lipid droplets were lower in GO orbital fibroblasts transfected with miR-27a and miR-27b mimics than in negative controls. Conclusions: Our results indicated that miR-27a and miR-27b inhibited adipogenesis in orbital fibroblasts from GO patients. Further studies are required to examine the potential of miR-27a and miR-27b as targets for therapeutic strategies. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor-like weak inducer of apoptosis (TWEAK), along with its receptor fibroblast growth factor-inducible (Fn)14, is associated with various biological activities including inflammation. However, its role in the pathogenesis of Graves’ orbitopathy (GO) is unknown. In this study, we investigated the mechanism by which TWEAK regulates inflammatory signaling in orbital fibroblasts from GO patients. We found that TWEAK and tumor necrosis factor-α (TNFA) mRNA levels were upregulated in GO as compared to non-GO tissue samples. TWEAK, TNF receptor (TNFR)1, TNFR2, and TNFR superfamily member 12A mRNA, and TWEAK and Fn14 protein levels were increased by interleukin (IL)-1β and TNF-α treatment. Treatment with exogenous recombinant TWEAK increased the transcript and protein expression of the pro-inflammatory cytokines IL-6, IL-8, and monocyte chemoattractant protein-1 to a greater extent in GO than in non-GO cells, while treatment with the anti-Fn14 antibody ITEM4 suppressed TWEAK-induced pro-inflammatory cytokine release and hyaluronan production. Additionally, the serum level of TWEAK was higher in Graves’ disease patients with (341.86 ± 86.3 pg/ml) as compared to those without (294.09 ± 41.44 pg/ml) GO and healthy subjects (255.33 ± 39.38 pg/ml), and was positively correlated with clinical activity score (r = 0.629, P < 0.001) and thyroid binding immunoglobulin level (r = 0.659, P < 0.001). These results demonstrate that TWEAK/Fn14 signaling contributes to GO pathogenesis. Moreover, serum TWEAK level is a potential diagnostic biomarker for inflammatory GO, and modulating TWEAK activity may be an effective therapeutic strategy for suppressing inflammation and tissue remodeling in GO. [ABSTRACT FROM AUTHOR]

Background: Although a wide range of genetic influences on thyroid-stimulating hormone (TSH) and free thyroxine (fT4) levels have been reported, sex differences in the genetic influences have not been well described. Methods: We assessed TSH and fT4 levels in 2,250 subjects without thyroid peroxidase antibody, with data obtained from the Korea National Health and Nutrition Examination Surveys (KNHANES) conducted from 2013 to 2015. Using variance decomposition methods, the variation of TSH and fT4 levels was divided into genetic and environmental components common to both sexes, and to males and females separately. The genetic correlation between TSH and fT4 levels was also assessed in both sexes, and in males and females separately. Results: Narrow-sense heritability for TSH and fT4 were 54% and 56%, respectively. Sex-specific heritability for TSH levels was significantly higher in females than in males (75% and 41%, respectively; p = 0.037). Heritability for fT4 levels was not significantly different between males and females (62% and 52%, respectively; p = 0.335). TSH and fT4 levels showed a negative genetic correlation in females (ρg = -0.347, p = 0.040) after regressing out the influences of environmental covariates, but this correlation was not present in males (ρg = -0.160, p = 0.391). Conclusions: The genetic influences on individual TSH levels were more prominent in females than in males. In addition, female-specific pleiotropy between TSH and fT4 might be a clue that this stronger genetic influences in females would mainly affect thyroid function per se, rather than other TSH-related factors that do not primarily trigger the negative feedback loop between TSH and fT4. [ABSTRACT FROM AUTHOR]

3-hydroxybenzaldehyde (3-HBA) is a precursor compound for phenolic compounds like Protocatechuic aldehyde (PCA). From recent reports, PCA has shown vasculoprotective potency, but the effects of 3-HBA remain unclear. The aim of this study is to investigate the vasculoprotective effects of 3-HBA in endothelial cells, vascular smooth muscle cells and various animal models. We tested effects of 3-HBA in both vitro and vivo. 3-HBA showed that it prevents PDGF-induced vascular smooth muscle cells (VSMCs) migration and proliferation from MTS, BrdU assays and inhibition of AKT phosphorylation. It arrested S and G0/G1 phase of VSMC cell cycle in PI staining and it also showed inhibited expression levels of Rb1 and CD1. In human umbilical vein endothelial cells (HUVECs), 3-HBA inhibited inflammatory markers and signaling molecules (VCAM-1, ICAM-1, p-NF-κB and p-p38). For ex vivo, 3-HBA has shown dramatic effects in suppressing the sprouting from aortic ring of Spargue Dawley (SD) rats. In vivo data supported the vasculoprotective effects of 3-HBA as it inhibited angiogenesis from Matrigel Plug assay in C57BL6 mouse, prevented ADP-induced thrombus generation, increased blood circulation after formation of thrombus, and attenuated neointima formation induced by common carotid artery balloon injury of SD rats. 3-HBA, a novel therapeutic agent, has shown vasculoprotective potency in both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Olfactory receptor (OR)-associated events are mediated by well-conserved components in the olfactory epithelium, including olfactory G-protein (Golf), adenylate cyclase III (ACIII), and olfactory marker protein (OMP). The expression of ORs has recently been observed in non-olfactory tissues where they are involved in monitoring extracellular chemical cues. The large number of OR genes and their sequence similarities illustrate the need to find an effective and simple way to detect non-olfactory OR-associated events. In addition, expression profiles and physiological functions of ORs in non-olfactory tissues are largely unknown. To overcome limitations associated with using OR as a target protein, this study used OMP with Golf and ACIII as targets to screen for potential OR-mediated sensing systems in non-olfactory tissues. Here, we show using western blotting, real-time PCR, and single as well as double immunoassays that ORs and OR-associated proteins are co-expressed in diverse tissues. The results of immunohistochemical analyses showed OMP (+) cells in mouse heart and in the following cells using the corresponding marker proteins c-kit, keratin 14, calcitonin, and GFAP in mouse tissues: interstitial cells of Cajal of the bladder, medullary thymic epithelial cells of the thymus, parafollicular cells of the thyroid, and Leydig cells of the testis. The expression of ORs in OMP (+) tissues was analyzed using a refined microarray analysis and validated with RT-PCR and real-time PCR. Three ORs (olfr544, olfr558, and olfr1386) were expressed in the OMP (+) cells of the bladder and thyroid as shown using a co-immunostaining method. Together, these results suggest that OMP is involved in the OR-mediated signal transduction cascade with olfactory canonical signaling components between the nervous and endocrine systems. The results further demonstrate that OMP immunohistochemical analysis is a useful tool for identifying expression of ORs, suggesting OMP expression is an indicator of potential OR-mediated chemoreception in non-olfactory systems. [ABSTRACT FROM AUTHOR]

Protocatechuic aldehyde (PCA), a phenolic aldehyde, has therapeutic potency against atherosclerosis. Although PCA is known to inhibit the migration and proliferation of vascular smooth muscle cells and intravascular thrombosis, the underlying mechanism remains unclear. In this study, we investigated the protective effect of PCA on endothelial cells and injured vessels in vivo in association with G protein-coupled estrogen receptor-1 (GPER-1). With PCA treatment, cAMP production was increased in HUVECs, while GPER-1 expression was increased in both HUVECs and a rat aortic explant. PCA and G1, a GPER-1 agonist, reduced H2O2 stimulated ROS production in HUVECs, whereas, G15, a GPER-1 antagonist, increased ROS production further. These elevations were inhibited by co-treatment with PCA or G1. TNFα stimulated the expression of inflammatory markers (VCAM-1, ICAM-1 and CD40), phospho-NF-κB, phospho-p38 and HIF-1α; however, co-treatment with PCA or G1 down-regulated this expression significantly. Likewise, increased expression of inflammatory markers by treatment with G15 was inhibited by co-treatment with PCA. In re-endothelization, aortic ring sprouting and neointima formation assay, rat aortas treated with PCA or G1 showed accelerated re-endothelization of the endothelium and reduced sprouting and neointima formation. However, aortas from G15-treated rats showed decelerated re-endothelization and increased sprouting and neointima formation. The effects of G15 were restored by co-treatment with PCA or G1. Also, in the endothelia of these aortas, PCA and G1 increased CD31 and GPER-1 and decreased VCAM-1 and CD40 expression. In contrast, the opposite effect was observed in G15-treated endothelium. These results suggest that GPER-1 might mediate the protective effect of PCA on the endothelium. [ABSTRACT FROM AUTHOR]

Management of Graves' orbitopathy (GO) is challenging, as no reliable, specific, and safe medical therapeutic agents have yet been developed. We investigated the effect of quercetin in primary cultured orbital fibroblasts from GO, targeting pathways of inflammation, aberrant accumulation of extracellular matrix macromolecules, and adipose tissue expansion. Quercetin significantly attenuated intercellular adhesion molecule-1 (ICAM-1), interleukin (IL) -6, IL-8, and cyclooxygenase (COX) -2 mRNA expression, and inhibited IL-1β-induced increases in ICAM-1, IL-6, and IL-8 mRNA. Increased hyaluronan production induced by IL-1β or tumor necrosis factor-α was suppressed by quercetin in a dose- and time-dependent manner. Treatment with noncytotoxic doses of quercetin inhibited accumulation of intracytoplasmic lipid droplets and resulted in a dose-dependent decrease in expression of peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein (C/EBP) α, and C/EBPβ proteins. In conclusion, inhibition of inflammation, hyaluronan production, and adipogenesis by the natural plant product quercetin in vitro provides the basis for further study of its potential use in the treatment of GO.

Background: Loss-of-function in the apoptosis-inducing genes is known to facilitate tumorigenesis. AFX (FOXO4), a member of forkhead transcription factors functions as a tumor suppressor and has 2 isoforms, AFXalpha (505 a.a.) and AFXzeta (450 a.a.). In human cancer cells, we identified an N-terminally deleted form of AFXalpha (alpha198-505), translated from a downstream start and 2 short N-terminal AFX proteins (90, and 101 a.a.) produced by aberrant splicing., Methods and Findings: We investigated the expression and role of these AFX variants. Cell transduction study revealed that short N-terminal AFX proteins were not stable. Though alpha(198-505) protein expression was detected in the cytoplasm and nucleus, alpha(198-505) expressing cells did not show a nucleocytoplasmic shuttling mediated by PI3 kinase signaling. Whereas, we observed this shuttling in cells expressing either AFXalpha or AFXzeta protein. AFXzeta and alpha(198-505) lost the ability to transactivate BCL6 or suppress cyclin D2 gene expression. These variants did not induce cancer cell death whereas AFXalpha resulted in apoptosis. We found that AFXzeta and alpha(198-505) suppress the AFXalpha stimulation of BCL6 promoter in a dose dependent manner, indicating dominant negative activity. These variants also inhibited AFXalpha induction of apoptosis., Conclusions: Loss of function by aberrant splicing and the dominant negative activity of AFX variants may provide a mechanism for enhanced survival of neoplastic cells.