Preoperative Risk Factors for Proptosis Recurrence After Rehabilitative Orbital Decompression in Graves' Orbitopathy Patients.

PURPOSE: Rehabilitative orbital decompression treats disfiguring exophthalmos in patients with Graves' orbitopathy (GO). This study aimed to identify risk factors associated with the postoperative recurrence of proptosis after orbital decompression. DESIGN: Retrospective, case-control study. METHODS: This retrospective review included patients with GO who underwent rehabilitative orbital decompression for disfiguring proptosis in an inactive state with a low clinical activity score (0-2) between January 2017 and December 2020 by a single surgeon. Exophthalmos was measured using a Hertel exophthalmometer, and recurrence was defined as an increase of 2 mm or more after decompression during the follow-up period. The association between preoperative variables and proptosis recurrence was analyzed using multivariable logistic regression. RESULTS: Of the total 217 patients, 11 (5.1%) developed recurrence of proptosis during the follow-up period (range, 3-30; mean, 15.6 months). Univariate logistic regression analysis identified thyroid-stimulating hormone receptor antibody (TRAb) and thyroid-stimulating immunoglobulin (TSI) as significant factors for recurrence, with age, sex, smoking, disease duration, orbital radiotherapy, and total thyroidectomy history being nonsignificant. TRAb remained significant in a multivariate logistic regression analysis (odds ratio, 1.06; P = .014). Receiver operating characteristic curve analysis revealed an area under the curve of 0.86 with a sensitivity of 90.9% and specificity of 82.0% at a TRAb level of 7.96 IU/L. CONCLUSION: Preoperative TRAb and TSI are valuable markers to predict proptosis recurrence after orbital decompression. These results may help surgeons to decide the optimal timing for orbital decompression to lessen the risk of postoperative recurrence of proptosis.

Yes-Associated Protein Mediates the Transition from Inflammation to Fibrosis in Graves' Orbitopathy.

Background: In Graves' orbitopathy (GO), localized orbital inflammation within the fixed orbit often leads to a fibrotic phenotype resulting in restrictive myopathy or refractory proptosis. However, the molecular pathways related to the transition from inflammation to fibrosis in GO are less understood. Yes-associated protein (YAP) and its homolog, transcriptional coactivator with PDZ-binding motif (TAZ; a Hippo pathway effector), are critical mechanosensors of mechanical stimuli and activate signaling cascades for cell proliferation, differentiation, and transformation. In this study, we aimed to examine the role of YAP in both inflammatory and fibrotic GO pathogenesis. Methods: Based on RNA sequencing performed on freshly obtained orbital adipose tissue from patients with GO and healthy individuals, Gene Ontology analysis and gene set-enrichment analysis were performed to analyze gene-expression differences between GO and normal orbital tissues. The role of YAP in GO-related inflammation and fibrosis was studied in primary cultured orbital fibroblasts. The effects of interleukin-1ß (IL-1ß)-induced inflammation and transforming growth factor-beta (TGF-ß)-induced fibrosis on YAP expression were evaluated using real-time polymerase chain reaction and Western blotting analyses. The effects of YAP on inflammatory and fibrotic responses were also examined by YAP silencing or treatment with pharmacological YAP inhibitors. Results: RNA sequencing revealed enhanced YAP expression in GO orbital tissues. Gene Ontology analysis indicated that "response to mechanical stimulus"-related genes were overexpressed in GO orbital tissues, along with those enriched for the "adipose proliferation," "inflammatory responses," and "hormone stimulus responses" terms. IL-1ß did not enhance YAP expression, and YAP silencing decreased IL-1ß-induced IL-6 expression while increasing prostaglandin-endoperoxide synthase 2 expression, leading to paradoxical pro-inflammatory effects. Conversely, TGF-ß enhanced YAP expression, and YAP silencing and pharmacological YAP inhibitor (cerivastatin, verteporfin, TED-347, and CA3) treatment significantly reduced TGF-ß-induced myofibroblast differentiation and collagen formation. Conclusion: YAP, a mechanotransducer responding to mechanical stimuli, was strongly expressed in GO orbital tissues, and YAP was induced by TGF-ß in orbital fibroblasts. Our study establishes YAP as a novel mediator of GO pathobiology, potentially mediating the transition from early inflammation to chronic fibrosis in GO. The finding that YAP inhibition suppressed TGF-ß-induced fibrotic response suggests YAP as a therapeutic target against the fibrotic mechanism of GO.

The Role of Adipsin, Complement Factor D, in the Pathogenesis of Graves' Orbitopathy.

Purpose: Graves' orbitopathy (GO) is an orbital manifestation of autoimmune Graves' disease, and orbital fibroblast is considered a target cell, producing pro-inflammatory cytokines and/or differentiating into adipocytes. Adipose tissue has been focused on as an endocrine and inflammatory organ secreting adipokines. We investigated the pathogenic role of a specific adipokine, adipsin, known as complement factor D in Graves' orbital fibroblasts. Methods: The messenger RNA (mRNA) expression of multiple adipokines was investigated in adipose tissues harvested from GO and healthy subjects. Adipsin protein production was analyzed in primary cultured orbital fibroblasts under insulin growth factor (IGF)-1, CD40 ligand (CD40L) stimulation, and adipogenesis. The effect of blocking adipsin with small interfering RNA (siRNA) on pro-inflammatory cytokine production and adipogenesis was evaluated using quantitative real-time PCR, Western blot, and ELISA. Adipogenic differentiation was identified using Oil Red O staining. Results: Adipsin gene expression was significantly elevated in GO tissue and increased after the stimulation of IGF-1 and CD40L, as well as adipocyte differentiation in GO cells. Silencing of adipsin suppressed IGF-1-induced IL-6, IL-8, COX2, ICAM-1, CCL2 gene expression, and IL-6 protein secretion. Adipsin suppression also attenuated adipocyte differentiation. Exogenous treatment of recombinant adipsin resulted in the activation of the Akt, ERK, p-38, and JNK signaling pathways. Conclusions: Adipsin, secreted by orbital fibroblasts, may play a distinct role in the pathogenesis of GO. Inhibition of adipsin ameliorated the production of pro-inflammatory cytokines and adipogenesis in orbital fibroblasts. Our study provides an in vitro basis suggesting adipsin as a potential therapeutic target for GO treatment.

Sarcopenia as a potential risk factor for senile blepharoptosis: Nationwide Surveys (KNHANES 2008-2011).

As the world's population is aging, sarcopenia is recognized as essential to assess people's lifelong condition and do appropriate early intervention. Senile blepharoptosis is also a problem in old age deteriorating visual function and causing a cosmetic decline. We investigated the association between sarcopenia and the prevalence of senile blepharoptosis, using a nationwide representative survey in Korea. A total of 11,533 participants were recruited. We used the body mass index (BMI)- adjusted appendicular skeletal muscle (ASM) definition as the muscle mass index (MMI, ASM [kg] divided by BMI [kg/m2]). The association between blepharoptosis prevalence and MMI was analyzed using multivariate logistic regression. Sarcopenia, defined as the lowest MMI quintile group in both men and women, was also associated with the prevalence of blepharoptosis (ORs 1.92, 95% CI 1.17-2.16; p < 0.001). These associations remained statistically significant after adjusting for various factors related to blepharoptosis using multivariate analysis (ORs 1.18, 95% CI 1.04-1.34; p = 0.012). Moreover, MMI was found to have a proportional relationship with eyelid lifting force (levator function), which is closely related to the occurrence and severity of ptosis. Sarcopenia is related to the prevalence of senile blepharoptosis, and patients with lower MMI were more likely to have blepharoptosis. These results suggest that sarcopenia can affect visual function and aesthetics.

Therapeutic effect of ibrutinib, a selective Bruton's tyrosine kinase inhibitor, in orbital fibroblasts from patients with Graves' orbitopathy.

PURPOSE: Bruton's tyrosine kinase (BTK) is an essential protein in B-cell antigen receptor (BCR) signaling pathway and is known to be related to pathogenetic effect on B-cell related malignancies and various autoimmune diseases. In this study, we investigated the therapeutic effect of ibrutinib, an orally bioavailable BTK inhibitor in the pathogenesis of Graves' orbitopathy (GO) in in vitro model. METHODS: Expression of BTK in orbital tissues from GO and normal control subjects were evaluated by real-time polymerase chain reaction (PCR). Primary cultured orbital fibroblasts from each subject were exposed to ibrutinib and stimulated with interleukin (IL)-1ß or insulin like growth factor (IGF)-1. Production of inflammatory cytokines was evaluated by real time PCR and enzyme-linked immunosorbent assays (ELISA). The downstream transcription factors were also determined by western blot assays. RESULTS: The expression of BTK in GO tissues were significantly higher than in healthy controls. After stimulation of GO orbital fibroblasts with IL-1ß or IGF-1, BTK mRNA and phosphorylated (p)- BTK protein expression was also enhanced. Ibrutinib reduced the expression of BTK mRNA and proteins of p-BTK, and inhibited the IL-1ß- and IGF-1-induced production of proinflammatory cytokines including IL-6, IL-8 and COX-2 in both GO and normal cells. Ibrutinib also significantly attenuated phosphorylation of Akt, p38, c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-κB) in IL-1ß stimulated GO cells and Akt, JNK, and NF-κB in IL-1ß stimulated normal cells. CONCLUSIONS: BTK expression is enhanced in GO tissue and orbital fibroblasts. Ibrutinib, a BTK inhibitor suppresses proinflammatory cytokine production as well as phosphorylation of Akt and NF-κB protein. Our results suggest the potential role of BTK in GO inflammatory pathogenesis and possibility of a novel therapeutic target of GO.

Endoscopic transorbital approach to the cavernous sinus: Cadaveric anatomy study and clinical application (‡SevEN-009).

Objective: Cavernous sinus (CS) invasion is frequently encountered in the management of skull base tumors. Surgical treatment of tumors in the CS is technically demanding, and selection of an optimal surgical approach is critical for maximal tumor removal and patient safety. We aimed to evaluate the feasibility of an endoscopic transorbital approach (ETOA) to the CS based on a cadaveric study. Methods: Five cadaveric heads were used for dissection under the ETOA in the comparison with the endoscopic endonasal approach (EEA) and the microscopic transcranial approach (TCA). The CS was exposed, accessed, and explored, first using the ETOA, followed by the EEA and TCA. A dedicated endoscopic system aided by neuronavigation guidance was used for the procedures. During the ETOA, neurovascular structures inside the CS were approached through different surgical triangles. Results: After completing the ETOA with interdural dissection, the lateral wall of the CS was fully exposed. The lateral and posterior compartments of the CS, of which accessibility is greatly limited under the EEA, were effectively approached and explored under the ETOA. The anteromedial triangle was the largest window via which most of the lateral compartment was freely approached. The internal carotid artery and abducens nerve were also observed through the anteromedial triangle and just behind V1. During the ETOA, the approaching view through the supratrochlear and infratrochlear triangles was more directed towards the posterior compartment. After validation of the feasibility and safety based on the cadaveric study, ETOA was successfully performed in a patient with a pituitary adenoma with extensive CS invasion. Conclusions: Based on the cadaveric study, we demonstrated that the lateral CS wall was reliably accessed under the ETOA. The lateral and posterior compartments of the CS were effectively explored via surgical triangles under the ETOA. ETOA provides a unique and valuable surgical route to the CS with a promising synergy when used with EEA and TCA. Our experience with a clinical case convinces us of the efficacy of the ETOA during surgical management of skull base tumors with CS-invasion.

Potential Therapeutic Role of Bone Morphogenic Protein 7 (BMP7) in the Pathogenesis of Graves' Orbitopathy.

Purpose: We investigated a role of bone morphogenic protein 7 (BMP7), a member of the TGF-ß superfamily on pathogenic mechanism of Graves' orbitopathy (GO). The therapeutic effects of BMP7 on inflammation and fibrosis were evaluated in cultured Graves' orbital fibroblasts. Methods: Expression of BMP7 was compared in cultured orbital tissue explants from GO (n = 12) and normal control (n = 12) subjects using real-time PCR. Orbital fibroblasts were cultured from orbital connective tissues obtained from GO (n = 3) and normal control patients (n = 3). Cells were pretreated with recombinant human BMP7 (rhBMP7) before stimulation with TGF-ß, IL-1ß, and TNF-α. Fibrosis-related proteins and inflammatory cytokines were analyzed by Western blotting. The activation of signaling molecules in inflammation and fibrosis was also analyzed. Results: The expressions of BMP7 mRNA were lower in GO orbital tissues than control. Fibrosis-related proteins, fibronectin, collagen 1α, and α-SMA induced by TGF-ß were suppressed by treating rhBMP7, and rhBMP7 upregulated TGF-ß induced SMAD1/5/8 protein expression, whereas downregulated SMAD2/3. Increased pro-inflammatory molecules, IL-6, IL-8, and intercellular adhesion molecule-1 (ICAM-1) by IL-1ß or TNF-α were blocked by rhBMP7 treatment, and the expression of phosphorylated NFκB and Akt was suppressed by rhBMP7 treatment. Conclusions: BMP7 transcript levels were downregulated in Graves' orbital tissues. Exogenous BMP7 treatment showed inhibitory effects on the production of profibrotic proteins and proinflammatory cytokines in orbital fibroblasts. Our results provide a molecular basis of BMP7 as a new potential therapeutic agent through the opposing mechanism of profibrotic TGF-ß/SMAD signaling and proinflammatory cytokine production.

Longitudinal association of thyroid-stimulating immunoglobulin levels with clinical characteristics in thyroid eye disease.

OBJECTIVES: The clinical course of thyroid eye disease (TED) is heterogeneous and predicting patients who may develop the severe sequelae of the disease is difficult. In this study, we evaluated the longitudinal association between changes in serum thyroid-stimulating hormone (TSH) receptor antibody (TRAb) levels and course of disease activity and severity over time. DESIGN: This was a multicentre, prospective, observational study. SETTING: Fifteen tertiary care oculoplastic service centres in Korea. PARTICIPANTS: Seventy-six patients with newly diagnosed TED were included and followed up for 12 months. METHODS: We evaluated clinical characteristics and serum TRAb levels at baseline, 6 and 12 months of TED diagnosis. Additionally, we analysed longitudinal associations between the serum TRAb levels and clinical activity score (CAS), no signs or symptoms, only signs, soft tissue involvement, proptosis, extraocular muscle involvement, corneal involvement, sight loss (NOSPECS) score and proptosis. RESULTS: Thyroid-stimulating immunoglobulin (TSI) and TSH-binding inhibitory immunoglobulin (TBII) levels decreased during the 1-year follow-up, whereas disease activity measured using CAS decreased mainly in the first 6 months. Disease severity measured using NOSPECS score and proptosis remained unchanged. Moreover, inter-person differences in TBII levels were associated with CAS, NOSPECS score and proptosis over time, whereas inter-person differences in TSI levels were associated with NOSPECS score. Subgroup analysis of patients with a baseline CAS≥4 demonstrated that within-person changes in TSI levels affected the CAS and NOSPECS score. CONCLUSIONS: Follow-up measurement of serum TSI and TBII levels may help evaluate TED prognosis and enable accurate clinical decision-making.

Quantitative assessment of increase in orbital volume after orbital floor fracture reconstruction using a bioabsorbable implant.

PURPOSE: To assess the postoperative changes in the orbital volume and the degree of enophthalmos after orbital floor fracture reconstruction using a bioabsorbable implant and to determine the predictors of postoperative orbital volume change. METHODS: Single-center, retrospective case series of 16 patients who underwent orbital floor fracture reconstruction using a bioabsorbable implant [poly(L-lactic acid)-poly(glycolic acid)/ß-tricalcium phosphate; Biobsorb ß®] were included. Three-dimensional volumetric calculations of orbit were determined using computed tomography scans and the degree of enophthalmos was assessed via Hertel exophthalmometry. Postoperative changes in the orbital volume and the degree of enophthalmos and their correlation were assessed. RESULTS: The mean volume of fractured orbits immediately after surgery was 22.26 ± 1.98 cm3, increasing to 23.67 ± 2.00 cm3 at 6-month follow-up (p < 0.001); the increased orbital volume was associated with postoperative deformation of the implant. The mean degree of enophthalmos was 0.09 ± 0.27 mm at 1-month follow-up, which increased to 0.66 ± 0.30 mm at 6-month follow-up (p = 0.001). Increase in orbital volume and enophthalmos progression showed a linear correlation (R = 0.682, p = 0.004). Patients with more herniated orbital tissue preoperatively showed increased postoperative orbital volume change (p = 0.015), whereas the size of the fracture area was not predictive of postoperative orbital volume change (p = 0.442). CONCLUSION: Increase in orbital volume by deformation of the bioabsorbable implant resulted in progressive enophthalmos during the postoperative follow-up period after orbital floor fracture reconstruction. Thus, careful selection of proper implants before surgery and close postoperative follow-up is needed for an optimal outcome.

Serum Selenium Levels in Patients with Graves Disease: Associations with Clinical Activity and Severity in a Retrospective Case-control Study.

PURPOSE: To compare serum selenium levels in Graves patients and non-Graves control participants and to evaluate associations between serum selenium levels and clinical features of Graves orbitopathy (GO). METHODS: We conducted a single-center, retrospective case-control study among 33 patients with Graves disease without GO (GD), 31 patients with diagnosed GO, and 27 unaffected healthy participants enrolled between 2013 and 2020 at Severance Hospital. We compared serum selenium concentrations between the GD, GO, and healthy control groups, and analyzed associations between serum selenium and GO patients' clinical activity scores, severity (assessed through modified NOSPECS scores), and other clinical features using multivariate linear regression analysis. RESULTS: Mean serum selenium levels were 109.30 ± 16.39, 111.39 ± 14.04, and 126.09 ± 21.09 ng/mL in GO patients, GD patients, and healthy control participants, respectively. Mean serum selenium levels in Graves patients with and without orbitopathy were significantly lower than those in the healthy control group (p < 0.05), and mean selenium levels were slightly lower in GO than those in GD patients (p = 0.594). Serum selenium levels were significantly lower in GO patients with eyelid retraction than in patients without retraction (p = 0.038). However, serum selenium levels were not associated with clinical activity scores and modified NOSPECS scores (p = 0.241 and 0.801, respectively). CONCLUSIONS: Serum selenium levels were significantly lower in Graves patients with or without GO, compared to non-Graves control participants. Selenium levels were not associated with clinical activity scores or NOSPECS scores, though we observed an association with eyelid retraction.

Signal transducer and activator of transcription 3 as a potential therapeutic target for Graves' orbitopathy.

The roles of signal transducer and activator of transcription 3 (STAT3) in inflammation, oxidative stress, and adipogenesis during Graves' orbitopathy (GO) are incompletely understood. Here, STAT3 expression in orbital tissues (from individuals with GO and healthy control subjects) was studied, and the role of STAT3 in GO pathogenesis was examined through small-interfering RNA (siRNA)-mediated silencing in primary orbital fibroblasts. STAT3 mRNA expression was higher in GO orbital tissues than in non-GO tissues. Treatment with proinflammatory cytokines, thyroid-stimulating hormone, or insulin-like growth factor-1 induced STAT3 mRNA in GO orbital fibroblasts, but not in non-GO cells. STAT3 silencing inhibited interleukin-1ß-induced inflammatory cytokines and oxidative stress-induced haem oxygenase-1 expression. STAT3 siRNA-transfected GO orbital fibroblasts showed decreased adipocyte differentiation. STAT3 affected proinflammatory cytokine production, oxidative stress responses, and adipogenesis in an in vitro model of GO, suggesting that STAT3 mediates GO pathology, and that modulating STAT3 expression may have therapeutic potential against GO.

PERK mediates oxidative stress and adipogenesis in Graves' orbitopathy pathogenesis.

We examined endoplasmic reticulum (ER) stress-related gene expression in orbital tissues from patients with Graves' orbitopathy (GO) and the effects of silencing protein kinase RNA-like endoplasmic reticulum kinase (PERK) in primary orbital fibroblast cultures to demonstrate the therapeutic potential of PERK-modulating agents in GO management. The expression of ER stress-related genes in orbital tissue harvested from individuals with or without GO was studied using real-time PCR. The role of PERK in GO pathogenesis was examined through small-interfering RNA (siRNA)-mediated silencing in cultured primary orbital fibroblasts. Intracellular reactive oxygen species (ROS) levels induced in response to cigarette smoke extract (CSE) or hydrogen peroxide were measured using 5-(and 6)-carboxy-20,70-dichlorodihydrofluorescein diacetate staining and flow cytometry. Cells were stained with Oil Red O, and adipogenesis-related transcription factor expression was evaluated through Wwestern blotting after adipogenic differentiation. PERK, activating transcription factor 4 (ATF4), and CCAAT-enhancer-binding protein (C/EBP)-homologous protein (CHOP) mRNA levels were significantly higher in GO orbital tissues than in non-GO orbital tissues. PERK silencing inhibited CSE- or hydrogen peroxide-induced ROS generation. After adipogenic differentiation, GO orbital fibroblasts revealed decreased lipid droplets and downregulation of C/EBPα, C/EBPß, and peroxisome proliferator-activator gamma (PPARγ) in PERK siRNA-transfected cells. The orbital tissues of patients with GO were exposed to chronic ER stress and subsequently exhibited enhanced unfolded protein response (especially through the PERK pathway). PERK silencing reduced oxidative stress and adipogenesis in GO orbital fibroblasts in vitro. Our results imply that PERK-modulating agents can potentially be used to manage GO.

A Pilot Clinical Study of Ocular Prosthesis Fabricated by Three-dimensional Printing and Sublimation Technique.

PURPOSE: We sought to evaluate the safety and effectiveness of patient-specific ocular prostheses produced by three-dimensional (3D) printing and the sublimation technique. A comparison with prostheses produced using manual manufacturing methods was then performed. METHODS: To confirm the biological and physiochemical safety, cytotoxicity, systemic acute toxicity, intradermal reaction, and skin sensitization tests were conducted according to the International Organization for Standardization guidelines. The compressive strength of the prostheses was also tested. Further, a case series of three patients who wore the 3D printed prostheses for more than eight hours daily for 4 weeks was executed. Self-assessments by these individuals using a questionnaire and safety evaluations focusing on the occurrence of conjunctival inflammation or allergic reactions according to the Cornea and Contact Lens Research Unit criteria by slit-lamp examination and similarity assessment were completed. RESULTS: The 3D printed ocular prostheses met the necessary qualifications per the biological and physiochemical safety tests, showing the absence of cytotoxicity, acute systemic toxicity, intradermal reactivity, and skin-sensitizing potency. Also, there was no difference in strength test results between previous ocular prostheses and the 3D printed ones. Self-assessment by the patients yielded satisfactory results, with no significant difference in the level of satisfaction reported for the 3D printed and previous handmade ocular prostheses. The 3D printed prosthesis did not trigger any side effects in the conjunctival sac and showed similar objective findings with respect to the color of the iris, sclera, and vessel patterns. CONCLUSIONS: Our study confirms the biologic and physiochemical safety of 3D-printed ocular prostheses created using computer-aided design technology and a sublimation technique. The patients' questionnaires and the judgment of the ophthalmologists/ocularists showed that the 3D printed ocular prosthesis was acceptable in function and appearance through a case series report.

The underestimated incidence of an orbital angioleiomyoma is possibly associated with an orbital cavernous hemangioma: illustrative case.

BACKGROUND: Orbital angioleiomyoma is generally considered a rare tumor; approximately 40 cases have been reported. However, after their experience with 6 consecutive cases in their single institution during 3 years, the authors speculate that the incidence of orbital angioleiomyomas is possibly underestimated. OBSERVATIONS: A 34-year-old female presented with progressive exophthalmos of 2 years' duration. Orbital computed tomography and magnetic resonance imaging revealed a well-circumscribed orbital tumor with partial and heterogeneous gadolinium enhancement. Technetium-99m red blood cell single-photon emission computed tomography showed positive perfusion in the late blood-pool phase, which was exactly consistent with the finding of a cavernous hemangioma. Under the impression of a cavernous hemangioma, the authors accessed the mass with an endoscopic endonasal approach and completely removed it without neurological deficit. Pathological examination revealed that the final diagnosis was an angioleiomyoma with positive immunostaining results for smooth muscle actin (SMA). LESSONS: The incidence of orbital angioleiomyomas may not be very low, as these lesions have possibly been misdiagnosed as orbital cavernous hemangiomas because of their histological similarity. Preoperative presumption and differentiation from cavernous hemangiomas are very challenging because of the rarity of orbital angioleiomyoma and similar radiological findings. SMA immunostaining may be critical to differentiate orbital angioleiomyomas from cavernous hemangiomas.

Role of binding immunoglobulin protein (BiP) in Graves' orbitopathy pathogenesis.

Inflammation and adipogenesis represent the main pathogenic mechanisms of Graves' orbitopathy (GO), and oxidative stress is a well-known inducer of GO pathology. Endoplasmic reticulum (ER) stress has been suggested as a major contributor to inflammation and reactive oxygen species (ROS) generation. In this study, we investigated the role of the ER-stress chaperone protein, binding immunoglobulin protein (BiP), in GO pathogenesis. Using primary cultures of orbital fibroblasts from patients with GO, we examined the role of BiP in GO pathogenesis by silencing its expression with small-interfering RNA (siRNA). Inflammatory cytokine expression was analysed by Western blotting and ELISA. Intracellular ROS levels induced by hydrogen peroxide or cigarette smoke extract were measured by 5-(and 6)-carboxy-20,70-dichlorodihydrofluorescein diacetate staining and flow cytometry. After adipogenic differentiation in BiP siRNA-transfected cells, the cells were stained with Oil Red O, and the levels of adipogenic transcription factors were determined by Western blot analysis. BiP mRNA expression levels were significantly higher in GO orbital tissues than in non-GO orbital tissues. Silencing BiP attenuated the expression of pro-inflammatory cytokines (interleukin-6, intercellular adhesion molecule-1, and monocyte chemotactic protein-1) in primary cultured GO orbital fibroblasts. Silencing BiP also reduced ROS generation, hyaluronan production, and adipocyte differentiation. These findings suggest that ER stress is involved in the aetiology of GO and that modulation of ER stress has therapeutic potential for GO.

Protein tyrosine phosphatase 1B as a therapeutic target for Graves' orbitopathy in an in vitro model.

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)-1ß, cigarette smoke extract (CSE), H2O2, and transforming growth factor (TGF)-ß 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-1ß, 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-1ß-induced inflammatory cytokine production, CSE- and H2O2-induced ROS synthesis, and TGF-ß-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.

Anti-oxidative and anti-adipogenic effects of caffeine in an in vitro model of Graves' orbitopathy.

Oxidative stress and adipogenesis play key roles in the pathogenesis of Graves' orbitopathy (GO). In this study, the therapeutic effects of caffeine on the reduction of oxidative stress and adipogenesis were evaluated in primary cultured GO orbital fibroblasts in vitro. Orbital fibroblasts were cultured from orbital connective tissues obtained from individuals with GO. Intracellular reactive oxygen species (ROS) levels induced by hydrogen peroxide or cigarette smoke extract and the expression of anti-oxidative enzymes were measured after caffeine treatment. After adipogenic differentiation and caffeine treatment, cells were stained with Oil Red O and the levels of peroxisome proliferator activator γ (PPARγ), C/EBPα, and C/EBPß were determined by western blot analysis. Hydrogen peroxide and cigarette smoke extract increased the levels of intracellular ROS and anti-oxidative enzymes, which decreased in a dose-dependent manner upon pretreatment with caffeine in GO orbital fibroblasts. Oil Red-O staining results revealed a decrease in lipid droplets; furthermore, PPARγ, C/EBPα, and C/EBPß protein expression levels were inhibited upon treatment with caffeine during adipocyte differentiation. In conclusion, caffeine decreased oxidative stress and adipogenesis in GO orbital fibroblasts in vitro. These findings may contribute to the development of new types of caffeine-containing pharmacological agents for use in the management of GO.

Nasolacrimal stent with shape memory as an advanced alternative to silicone products.

Epiphora is the overflow of tears typically caused by obstruction or occlusion of the nasolacrimal duct. More attention is required to address this global health issue owing to the increase in air pollution. Implantation of a silicone stent is the preferred treatment for epiphora; however, introducing a silicone stent into a narrow duct with complex geometry is challenging as it requires guidance by a sharp metal needle. Additionally, silicone can cause adverse reactions such as biofilm formation and tear flow resistance due to its extreme hydrophobicity. To overcome these problems, in this study we developed a new type of biocompatible shape memory polymer (SMP) stent with elasticity capacity for self-expansion. First, SMPs in the form of x%poly(ε-caprolactone)-co-y%poly(glycidyl methacrylate) (x%PCL-y%PGMA) were synthesized via ring opening polymerization by varying the molar ratio of PCL (x%) and PGMA (y%). Second, the shape memory and mechanical properties were tuned by controlling the crosslinking degree and concentration of x%PCL-y%PGMA solution to produce a test type of SMP stent. Lastly, this 94%PCL-06%PGMA stent exhibited more standout critical functions in a series of in vitro and in vivo experiments such as a cell growth-supporting level of biocompatibility with nasal epithelial cells without significant inflammatory responses, better resistance to biofilm formation, and more efficient capacity to drain tear than the silicone control. Overall, 94%PCL-06%PGMA can be suggested as a superior alternative to the currently used materials for nasolacrimal stents. STATEMENT OF SIGNIFICANCE: Silicone intubation (stenting) has been widely used to treat nasolacrimal duct obstruction, however, it can cause adverse clinical effects such as bacterial infection; presents procedural challenges because of the curved nasolacrimal duct structure; and shows poor drainage efficiency stemming from the highly hydrophobic nature of silicone. In this work, we describe an innovative shape memory polymer (SMP) as a superior alternative to conventional silicone-based materials for nasolacrimal duct intubation. We demonstrate the clear advantages of the SMP over conventional silicone, including a much higher drainage capacity and superior resistance to bacterial infection.