Growth hormone releasing hormone signaling promotes Th17 cell differentiation and autoimmune inflammation.

Dysregulation of Th17 cell differentiation and pathogenicity contributes to multiple autoimmune and inflammatory diseases. Previously growth hormone releasing hormone receptor (GHRH-R) deficient mice have been reported to be less susceptible to the induction of experimental autoimmune encephalomyelitis. Here, we show GHRH-R is an important regulator of Th17 cell differentiation in Th17 cell-mediated ocular and neural inflammation. We find that GHRH-R is not expressed in naïve CD4+ T cells, while its expression is induced throughout Th17 cell differentiation in vitro. Mechanistically, GHRH-R activates the JAK-STAT3 pathway, increases the phosphorylation of STAT3, enhances both non-pathogenic and pathogenic Th17 cell differentiation and promotes the gene expression signatures of pathogenic Th17 cells. Enhancing this signaling by GHRH agonist promotes, while inhibiting this signaling by GHRH antagonist or GHRH-R deficiency reduces, Th17 cell differentiation in vitro and Th17 cell-mediated ocular and neural inflammation in vivo. Thus, GHRH-R signaling functions as a critical factor that regulates Th17 cell differentiation and Th17 cell-mediated autoimmune ocular and neural inflammation.

rTMS ameliorates depression/anxiety-like behaviors in experimental autoimmune encephalitis by inhibiting neurotoxic reactive astrocytes.

One third of patients with multiple sclerosis (MS) suffered from depressive symptoms. The pathogenesis of depression in MS patients has been related to innate immune activation in certain regions of the brain such as hippocampus. However, pharmacotherapy lacks sufficient evidence for beneficial effects on depression in MS patients, urging for a novel treatment modality for this mental disorder. Treatment effects of rTMS on depression/anxiety-like behaviors in mice with experimental autoimmune encephalomyelitis (EAE) were assessed by behavioral tests. The role of innate immune response was examined by RNA sequencing, quantitative RT-PCR, and immunofluorescence techniques. Depressive symptom severity and astroglial activation in patients with MS were assessed by Beck Depression Inventory and serum glial fibrillary acidic protein (GFAP), respectively. EAE mice displayed depression/anxiety-like behaviors, which were ameliorated by rTMS. Transcriptome and gene-specific expression analysis of the hippocampus showed significant reduction in transcript levels associated with neurotoxic reactive astrocytes in EAE mice after rTMS treatment. This was confirmed by immunofluorescence studies. Complement component 3d, a marker of neurotoxic reactive astrocytes, was highly expressed in EAE hippocampus, but was reduced to a basal level after rTMS treatment. In patients with MS, astroglial activation, indicated by serum GFAP levels, was significantly elevated in those with moderate or major depressive symptoms. These findings support that the suppression of neurotoxic reactive astrocytes might be a potential target for treatment of depression in patients with MS, and suggest the potential of using rTMS as a potential therapeutic treatment for this disorder.

ELEVATED LEVEL OF URIC ACID, BUT NOT GLUCOSE, IN AQUEOUS HUMOR AS A RISK FACTOR FOR DIABETIC MACULAR EDEMA IN PATIENTS WITH TYPE 2 DIABETES.

PURPOSE: To determine the association of uric acid (UA) and glucose in aqueous humor with diabetic macular edema (DME) in patients with Type 2 diabetes. METHODS: Patients with DME or diabetes mellitus without retinopathy were enrolled from August 2016 to December 2020. Nondiabetic patients with age-related cataract or age-related macular degeneration were included as controls. RESULTS: A total of 585 eyes from 585 patients were included for this study. Statistical analysis showed that aqueous UA was associated with central retinal thickness (r = 0.39, P < 0.0001), with higher levels of UA in severe DME and lower levels in mild DME, suggesting an ocular source of UA from the diabetic retina. Aqueous UA {odds ratio (OR), 6.88 (95% confidence interval [CI], 2.61-18.12)}, but not aqueous glucose (0.95 [95% CI, 0.73-1.23]) or serum UA (0.90 [95% CI, 0.66-1.23]), was a stronger predictor for DME than the duration of DM (1.26 [95% CI, 1.12-1.42]) or hemoglobin A1c (1.35 [95% CI, 0.99-1.83]). If aqueous UA (<2.46 mg/dL) and aqueous glucose (<6.43 mmol/L) were used as reference, high UA (≥2.46 mg/dL) alone was associated with 5.83-fold increase in risk of DME, but high glucose (≥6.43 mg/dL) alone was not associated with DME. CONCLUSION: Increased aqueous UA, but not glucose, is an independent risk factor for DME. These data suggest that an intravitreal UA-lowering therapy could be beneficial for DME.

Nogo-A Induced Polymerization of Microtubule Is Involved in the Inflammatory Heat Hyperalgesia in Rat Dorsal Root Ganglion Neurons.

The microtubule, a major constituent of cytoskeletons, was shown to bind and interact with transient receptor potential vanilloid subfamily member 1 (TRPV1), and serves a pivotal role to produce thermal hyperalgesia in inflammatory pain. Nogo-A is a modulator of microtubule assembly and plays a key role in maintaining the function of TRPV1 in inflammatory heat pain. However, whether the microtubule dynamics modulated by Nogo-A in dorsal root ganglion (DRG) neurons participate in the inflammatory pain is not elucidated. Here we reported that the polymerization of microtubules in the DRG neurons, as indicated by the acetylated α-tubulin, tubulin polymerization-promoting protein 3 (TPPP3), and microtubule numbers, was significantly elevated in the complete Freund's adjuvant (CFA) induced inflammatory pain. Consistent with our previous results, knock-out (KO) of Nogo-A protein significantly attenuated the heat hyperalgesia 72 h after CFA injection and decreased the microtubule polymerization via up-regulation of phosphorylation of collapsin response mediator protein 2 (CRMP2) in DRG. The colocalization of acetylated α-tubulin and TRPV1 in DRG neurons was also reduced dramatically in Nogo-A KO rats under inflammatory pain. Moreover, the down-regulation of TRPV1 in DRG of Nogo-A KO rats after injection of CFA was reversed by intrathecal injection of paclitaxel, a microtubule stabilizer. Furthermore, intrathecal injection of nocodazole (a microtubule disruptor) attenuated significantly the CFA-induced inflammatory heat hyperalgesia and the mechanical pain in a rat model of spared nerve injury (SNI). In these SNI cases, the Nogo-A and acetylated α-tubulin in DRG were also significantly up-regulated. We conclude that the polymerization of microtubules promoted by Nogo-A in DRG contributes to the development of inflammatory heat hyperalgesia mediated by TRPV1.

Ruxolitinib Alleviates Uveitis Caused by Salmonella typhimurium Endotoxin.

Uveitis is characterized by inflammatory lesions of intraocular structures. It is one of the important manifestations in patients with Reiter's syndrome, an inflammatory arthritis, which is caused by enteric infection with bacteria, including Salmonella typhimurium. Corticosteroids remain the most frequently used therapies against uveitis associating with inflammatory arthritis. However, the long-term administration of steroids results in many side effects, and some uveitis patients do not respond to steroid treatment. Non-steroidal treatments are needed for uveitis patients. Our previous study found that Janus kinase (JAK) 1/2 inhibitor, ruxolitinib could suppress the expression of proinflammatory mediators in the ciliary body and iris. However, the impacts of ruxolitinib on ophthalmic features in uveitic eyes are still unknown. In this study, Salmonella typhimurium endotoxin-induced uveitis (EIU) was induced in Sprague Dawley rats by the injection of lipopolysaccharide (LPS). Compared with LPS-induced rats treated with water, ruxolitinib significantly attenuated the clinical manifestations, infiltrating cells and protein exudation in the aqueous humor, and retina-choroid thickening. Amplitudes of b-wave in both scotopic and photopic electroretinogram (ERG), and the amplitude of a-wave in scotopic ERG in EIU animals were alleviated by ruxolitinib. Collectively, we propose ruxolitinib could attenuate endotoxin-induced uveitis and rescue visual functions in rats by inhibiting the JAK2-STAT3 pathway.

Agonist of growth hormone-releasing hormone enhances retinal ganglion cell protection induced by macrophages after optic nerve injury.

Optic neuropathies are leading causes of irreversible visual impairment and blindness, currently affecting more than 100 million people worldwide. Glaucoma is a group of optic neuropathies attributed to progressive degeneration of retinal ganglion cells (RGCs). We have previously demonstrated an increase in survival of RGCs by the activation of macrophages, whereas the inhibition of macrophages was involved in the alleviation on endotoxin-induced inflammation by antagonist of growth hormone-releasing hormone (GHRH). Herein, we hypothesized that GHRH receptor (GHRH-R) signaling could be involved in the survival of RGCs mediated by inflammation. We found the expression of GHRH-R in RGCs of adult rat retina. After optic nerve crush, subcutaneous application of GHRH agonist MR-409 or antagonist MIA-602 promoted the survival of RGCs. Both the GHRH agonist and antagonist increased the phosphorylation of Akt in the retina, but only agonist MR-409 promoted microglia activation in the retina. The antagonist MIA-602 reduced significantly the expression of inflammation-related genes Il1b, Il6, and Tnf Moreover, agonist MR-409 further enhanced the promotion of RGC survival by lens injury or zymosan-induced macrophage activation, whereas antagonist MIA-602 attenuated the enhancement in RGC survival. Our findings reveal the protective effect of agonistic analogs of GHRH on RGCs in rats after optic nerve injury and its additive effect to macrophage activation, indicating a therapeutic potential of GHRH agonists for the protection of RGCs against optic neuropathies especially in glaucoma.

rad21 Is Involved in Corneal Stroma Development by Regulating Neural Crest Migration.

Previously, we identified RAD21R450C from a peripheral sclerocornea pedigree. Injection of this rad21 variant mRNA into Xenopus laevis embryos disrupted the organization of corneal stroma fibrils. To understand the mechanisms of RAD21-mediated corneal stroma defects, gene expression and chromosome conformation analysis were performed using cells from family members affected by peripheral sclerocornea. Both gene expression and chromosome conformation of cell adhesion genes were affected in cells carrying the heterozygous rad21 variant. Since cell migration is essential in early embryonic development and sclerocornea is a congenital disease, we studied neural crest migration during cornea development in X. laevis embryos. In X. laevis embryos injected with rad21 mutant mRNA, neural crest migration was disrupted, and the number of neural crest-derived periocular mesenchymes decreased significantly in the corneal stroma region. Our data indicate that the RAD21R450C variant contributes to peripheral sclerocornea by modifying chromosome conformation and gene expression, therefore disturbing neural crest cell migration, which suggests RAD21 plays a key role in corneal stroma development.

Elevated level of uric acid in aqueous humour is associated with posterior subcapsular cataract in human lens.

IMPORTANCE: Age-related cataract is the leading cause of blindness worldwide. The pathological mechanisms causing this disease remain elusive. BACKGROUND: To examine the involvement of uric acid (UA) in the pathogenesis of posterior subcapsular cataract (PSC). DESIGN: Retrospective study and experimental investigation. PARTICIPANTS: A total of 180 patients with PSC or non-PSC were included. METHODS: Samples obtained from the patients were used to analyse content of UA and for histochemical examinations. The effects of UA on human lens epithelial cells were also investigated. MAIN OUTCOME MEASURES: Aqueous humour UA and urate deposits. RESULTS: The results showed a significant increase of aqueous humour UA in patients with PSC. After adjustment for potential confounders, elevated aqueous humour UA (odds ratio [OR] = 1.45) showed a stronger association with PSC than serum UA (OR = 1.10). Gomori methenamine silver staining revealed in PSC an intense deposit of urates in the lens fibres in equatorial regions, and in subcapsular fibres in posterior regions of the lens. Such staining was not detected in the lens with non-PSC. Treatment with UA-induced senescence and apoptosis in human lens epithelial cells in a dose dependent manner. Our results suggest that the elevated level of UA in aqueous humour causes a deposition of urates in human lens epithelium, which could possibly lead to dysfunction of these cells that generates opacification in PSC. CONCLUSIONS AND RELEVANCE: These findings indicate the local action of excessive UA in the pathogenesis of PSC. Control of serum UA level could delay the progression of PSC.

Identification of a new functional domain of Nogo-A that promotes inflammatory pain and inhibits neurite growth through binding to NgR1.

Nogo-A is a key inhibitory molecule to axon regeneration, and plays diverse roles in other pathological conditions, such as stroke, schizophrenia, and neurodegenerative diseases. Nogo-66 and Nogo-Δ20 fragments are two known functional domains of Nogo-A, which act through the Nogo-66 receptor (NgR1) and sphingosine-1-phosphate receptor 2 (S1PR2), respectively. Here, we reported a new functional domain of Nogo-A, Nogo-A aa 846-861, was identified in the Nogo-A-specific segment that promotes complete Freund's adjuvant (CFA)-induced inflammatory pain. Intrathecal injection of its antagonist peptide 846-861PE or the specific antibody attenuated the CFA-induced inflammatory heat hyperalgesia. The 846-861 PE reduced the content of transient receptor potential vanilloid subfamily member 1 (TRPV1) in dorsal root ganglia (DRG) and decreased the response of DRG neurons to capsaicin. These effects were accompanied by a reduction in LIMK/cofilin phosphorylation and actin polymerization. GST pull-down and fluorescence resonance energy transfer (FRET) assays both showed that Nogo-A aa 846-861 bound to NgR1. Moreover, we demonstrated that Nogo-A aa 846-861 inhibited neurite outgrowth from cortical neurons and DRG explants. We concluded that Nogo-A aa 846-861 is a novel ligand of NgR1, which activates the downstream signaling pathways that inhibit axon growth and promote inflammatory pain.

Analysis of axon divergence at the optic chiasm in nogo-a knockout mice.

Our earlier studies have shown that the axon growth inhibitory molecule Nogo affects axon routing at the optic chiasm likely through a differential regulation of Nogo receptor on the optic axons. Using isoform specific antibodies, we further showed that Nogo-A was predominantly expressed by retinal ganglion cells and their axons, while Nogo-B was highly localized on the radial glia at the midline of the chiasm, suggesting a role of Nogo-B in regulating turning of uncrossed axons. To further investigate the roles of Nogo-A in axon divergence, we analyzed the routing of axons in the chiasm of Nogo-A knockout mice during the growth of axons across the midline. At E13 to E16, there was no significant difference in the contralateral projection (P = 0.6943 for E13; P = 0.9867 for E14; P = 0.4121 for E15 and P = 0.3402 for E16). The results also showed the absence of Nogo-A did not cause any obvious change to the ipsilateral projection at the optic chiasm, both for the early generated uncrossed axons at E13 and E14 and the late cohorts at E15-E16, when compared with the wild-type mice (P = 0.4788 for E13; P = 0.188 for E14; P = 0.3152 for E15 and P = 0.432 for E16). These findings support that Nogo-A is not the major isoform to guide the axon divergence in the mouse optic chiasm.

Communication with family concerning body donation in Hong Kong: what do we know?

This study aimed to examine three major issues: (a) The extent to which registered donors have communicated with family about body donation; (b) The differences in demographics, life and death attitudes, and quality of relationship with family members between those who communicated their body donation decision and those who did not; (c) The factors associated with the act of communicating with family about body donation. A survey was conducted of people who registered in a body donation programme in Hong Kong. A total of 1,070 registered donors completed an online questionnaire between August and September 2016. The majority of participants (80.1%) reported that they communicated with family members about body donation. About one-third only informed family members of their decisions after registration, and around 15.6% did not communicate with family members. Those who communicated with family were significantly older and married; they also indicated more positive life and death attitudes and a better quality of relationship with family members. Three factors were found to have significant associations with the act of communicating with family members about the decision to donate the body: (a) Age, (b) Quality of life, (c) Quality of relationship with family members. Communication with family members about body donation is still inadequate. Future body donation programmes may focus more on the way body donation decisions can be better communicated with family members. Special attention can be given to younger registered donors who find it difficult to communicate with the older generation, those who indicate more negative life and death attitudes, and who experienced a poorer quality of relationship with family members.

Signaling mechanisms of growth hormone-releasing hormone receptor in LPS-induced acute ocular inflammation.

Ocular inflammation is a major cause of visual impairment attributed to dysregulation of the immune system. Previously, we have shown that the receptor for growth-hormone-releasing hormone (GHRH-R) affects multiple inflammatory processes. To clarify the pathological roles of GHRH-R in acute ocular inflammation, we investigated the inflammatory cascades mediated by this receptor. In human ciliary epithelial cells, the NF-κB subunit p65 was phosphorylated in response to stimulation with lipopolysaccharide (LPS), resulting in transcriptional up-regulation of GHRH-R. Bioinformatics analysis and coimmunoprecipitation showed that GHRH-R had a direct interaction with JAK2. JAK2, but not JAK1, JAK3, and TYK2, was elevated in ciliary body and iris after treatment with LPS in a rat model of endotoxin-induced uveitis. This elevation augmented the phosphorylation of STAT3 and production of proinflammatory factors, including IL-6, IL-17A, COX2, and iNOS. In explants of iris and ciliary body, the GHRH-R antagonist, MIA-602, suppressed phosphorylation of STAT3 and attenuated expression of downstream proinflammatory factors after LPS treatment. A similar suppression of STAT3 phosphorylation was observed in human ciliary epithelial cells. In vivo studies showed that blocking of the GHRH-R/JAK2/STAT3 axis with the JAK inhibitor Ruxolitinib alleviated partially the LPS-induced acute ocular inflammation by reducing inflammatory cells and protein leakage in the aqueous humor and by repressing expression of STAT3 target genes in rat ciliary body and iris and in human ciliary epithelial cells. Our findings indicate a functional role of the GHRH-R/JAK2/STAT3-signaling axis in acute anterior uveitis and suggest a therapeutic strategy based on treatment with antagonists targeting this signaling pathway.

Increased Expression of Growth Hormone-Releasing Hormone in Fibrinous Inflammation of Proliferative Diabetic Retinopathy.

PURPOSE: To investigate the involvement of growth hormone-releasing hormone (GHRH) - growth hormone (GH) signaling in pathogenesis of proliferative diabetic retinopathy (PDR). DESIGN: Experimental laboratory study. METHODS: Vitreous humor, aqueous humor, and serum were obtained from 36 eyes of 36 patients with or without type 2 diabetes from 2017 to 2019. For histologic examination, 6 fibrovascular membranes were excised from eyes with active PDR. Three fibrovascular membranes were excised from nondiabetic patients with proliferative vitreoretinopathy (PVR) as controls. RESULTS: In PDR, the fibrovascular tissues consisted of a mature region containing fibrocytes, and an immature region populated by abundant polymorphonuclear leukocytes in a fibrinogen meshwork. Clusters of leukocytes were found adhering to the vascular walls. In PVR, no fibrinogen and polymorphonuclear leukocyte was observed in the fibrovascular membranes. The levels of GHRH and GH in PDR were significantly increased (P < .001), with 1.8-fold and 72.8-fold in vitreous humor, and 2-fold and 4.9-fold in aqueous humor, respectively, when compared with corresponding levels in controls. No significant difference was detected for insulin-like growth factor-1. Immunohistochemistry showed intense expression of GHRH and its receptor GHRH-R in polymorphonuclear leukocytes, vascular endothelial cells, and fibrocytes in fibrovascular membranes of PDR. GHRH staining was not detectable in infiltrating cells within the fibrovascular membrane of PVR. CONCLUSIONS: These findings reveal a possible involvement of GHRH/GHRH-R in fibrinous inflammation that might contribute to the formation of fibrovascular membrane in PDR through mediating activities of leukocytes, vascular endothelial cells, and fibrocytes. Targeting GHRH/GHRH-R may be considered as a potential therapeutic approach for the treatment of PDR.

Understanding family involvement in body donation in Hong Kong: A qualitative study of registered donors and bereaved family members.

Encouraging the public to donate their bodies after death is crucial for anatomy teaching in medical education. In Hong Kong, success may be affected if family members override the registered donors' wish after death, and thus the role of family in body donation is worth more attention. This study aims to examine how family is involved in the process of body donation. A qualitative study was conducted in Hong Kong. Registered donors and bereaved family members were recruited from a body donation scheme organised by a medical school. In-depth interviews were done and thematic analysis was conducted. Five themes were found: (a) decision-making: individual versus family; (b) family conflicts: avoidance versus confrontation; (c) trust in family members: discuss versus do not discuss; (d) family members' struggles in implementation; (e) informed end-of-life planning. Findings revealed that donors may not necessarily discuss their decisions about body donation with family members directly. Instead, it was found that family was involved in the body donation process in different ways and to different extents. For example, donors considered family members' views about body donation, but they chose not to involve them in the discussions if they expected objections, in order to avoid conflicts. Bereaved family members considered understanding family members' body donation decisions prior to death important, and they shared the implications of body donation for funeral arrangements and the grieving process. Findings help to understand the role of the family in body donation, especially in the Hong Kong Chinese context, and may give insights into how the body donation scheme could be enhanced to facilitate better communication between registered donors and family members as well as to support bereaved family members in implementing the decision to donate.

Growth hormone-releasing hormone receptor mediates cytokine production in ciliary and iris epithelial cells during LPS-induced ocular inflammation.

The receptor for growth hormone-releasing hormone (GHRH-R) has been shown to upregulate specifically in the ciliary and iris epithelial cells and infiltrating cells in the aqueous humor in a rat model of acute anterior uveitis. Treatment with GHRHR-R antagonist alleviates significantly these inflammatory responses. Herein we investigated whether the ciliary and iris epithelial cells can respond directly to lipopolysaccharide (LPS) without the influences of circulating leukocytes to produce inflammatory mediators through a GHRH-R mediated mechanism. In explant cultures of rat ciliary body and iris, LPS caused a substantial increase of GHRH-R in 24 h. Immunohistochemistry showed a localization of TLR4, the receptor for LPS, and an elevated expression of IL-6 and IL-1ß in ciliary and iris epithelial cells after LPS treatment. LPS also elevated the level of IL-1ß, IL-6, and iNOS and increased secretion of IL-1ß and IL-6 from the explants. The GHRH-R antagonist, MIA-602, suppressed the elevated expression of IL-1ß and IL-6, and reduced the release of IL-6. Such effects were not seen for the GHRHR agonist, MR-409. When co-cultured with leukocytes, expression of GHRH-R in the ocular explants was further enhanced during LPS treatment. Our results demonstrate a direct action of LPS on ciliary and iris epithelial cells to produce pro-inflammatory factors through a GHRH-R mediated mechanism, and suggest a role of these epithelial cells, in addition to the resident antigen presenting cells, in immune surveillance of the eye. Infiltrating leukocytes may enhance these inflammatory responses by regulating GHRH-R in ciliary and iris epithelial cells, in addition to their functions of synthesizing proinflammatory cytokines.

Green tea catechins alleviate autoimmune symptoms and visual impairment in a murine model for human chronic intraocular inflammation by inhibiting Th17-associated pro-inflammatory gene expression.

Autoimmune uveitis is a sight-threatening disease mainly caused by dysregulation of immunity. We investigated the therapeutic effects of green tea extract (GTE) and its major component, epigallocatechin-3-gallate (EGCG), on a murine model of experimental autoimmune uveoretinitis (EAU). Oral administration of GTE, EGCG, dexamethasone, or water, which started 5 days before the induction, was fed every two days to each group. On day 21 post induction, the eyes were examined by confocal scanning laser ophthalmoscopy, optical coherence tomography (OCT), fundus fluorescein angiography (FFA) and electroretinography (ERG) prior to sacrificing the animals for histological assessments and gene expression studies. Retinal-choroidal thicknesses (RCT) and major retinal vessel diameter were measured on OCT sections and FFA images, respectively. Comparing to water-treated EAU animals, GTE attenuated uveitis clinical manifestations, RCT increase (1.100 ± 0.013 times vs 1.005 ± 0.012 times, P < 0.001), retinal vessel dilation (308.9 ± 6.189 units vs 240.8 units, P < 0.001), ERG amplitudes attenuation, histopathological ocular damages, and splenomegaly in EAU mice. The therapeutic effects of GTE were dose dependent and were comparable to dexamethasone. EGCG, a major active constituent of GTE, partially alleviated uveitic phenotypes including recovering visual function. Th-17 associated pro-inflammatory gene [interleukin 1 beta (IL-1ß), IL-6, IL-17A, and tumor necrosis factor alpha (TNF-α)] expressions were down regulated by GTE and EGCG treatments, which showed no detectable morphological defects in liver and kidney in non-induced and EAU mice. Our findings suggest that GTE consumption can serve as a potent therapeutic agent as well as a food supplement for developing alternative treatments against autoimmune uveitis.

Association of glycated hemoglobin with the risk of advanced fibrosis in non-alcoholic fatty liver disease patients without diabetes.

BACKGROUND: Association of diabetes with non-alcoholic steatohepatitis has been well documented. However, it remains unclear whether there is an association between levels of glycated hemoglobin (HbA1c) with severity of non-alcoholic fatty liver disease (NAFLD). This study was aimed to explore the relationship between levels of HbA1c and the risk of advanced fibrosis in patients with NAFLD. METHODS: A cross-sectional study was performed on 4826 apparently healthy Chinese, who underwent a health check between January 2015 and December 2016. NAFLD was defined as hepatic steatosis on ultrasonography in the absence of excessive alcohol use or other identifiable causes. The risk of advanced fibrosis was assessed by NAFLD fibrosis Score. RESULTS: Among 4826 individuals studied, 1630 were diagnosed with NAFLD. In a multivariable-adjusted model, high HbA1c levels were associated independently with increased prevalence of NAFLD. The adjusted odds ratio [95% confidence interval (95% CI)] for NAFLD, when compared with the highest HbA1c quartile and the lowest HbA1c quartile, was 2.72 (2.07-3.58; P for trend < 0.001). A strong association was also observed between HbA1c level and the risk of fibrosis in patients with NAFLD in multivariable analyses, with the extreme-quartile odds ratio of 2.69 (95% CI: 1.60-4.53; P for trend < 0.001). This association remained significant even in subjects without diabetes. CONCLUSIONS: We concluded that high HbA1c level was associated strongly and independently with increased risk of advanced fibrosis in NAFLD patients without diabetes.

Nogo-A promotes inflammatory heat hyperalgesia by maintaining TRPV-1 function in the rat dorsal root ganglion neuron.

Nogo-A is a key inhibitory molecule of axon regeneration in oligodendrocytes. However, little is known about its role in adult neurons. In this study, we showed an important function of Nogo-A on regulation of inflammatory pain in dorsal root ganglion (DRG) neurons. In adult rats with complete Freund's adjuvant (CFA) hind paw inflammation, DRG neurons showed a significant increase in Nogo-A expression. Disruption of Nogo-A signaling with Nogo-66 receptor antagonist peptide, Nogo-A blocking antibody, Nogo-A short hairpin RNA, or Nogo-A gene knockout attenuated CFA-induced inflammatory heat hyperalgesia. Moreover, disruption of Nogo-A signaling suppressed the function and expression in DRG neurons of the transient receptor potential vanilloid subfamily member (TRPV)-1 channel, which is known to be the endogenous transducer of noxious heat during inflammation. These effects were accompanied with a reduction in LIM domain kinase (LIMK)/cofilin phosphorylation and actin polymerization. Similar disruption of actin filament architecture by direct action of Latrunculin A reduced the TRPV-1 activity and up-regulation of TRPV-1 protein caused by CFA. We conclude that Nogo-A plays an essential role in the development of inflammatory heat hyperalgesia, partly through maintaining TRPV-1 function via activation of the LIMK/cofilin pathway, which regulates actin filament dynamics. These findings support a therapeutic potential of modulating Nogo-A signaling in pain management.-Hu, F., Liu, H.-C., Su, D.-Q., Chen, H.-J., Chan, S.-O., Wang, Y., Wang, J. Nogo-A promotes inflammatory heat hyperalgesia by maintaining TRPV-1 function in the rat dorsal root ganglion neuron.

Metabolomics of Green-Tea Catechins on Vascular-Endothelial-Growth-Factor-Stimulated Human-Endothelial-Cell Survival.

Neovascularization causes serious oculopathy related to upregulation of vascular-endothelial-growth factor (VEGF) causing new capillary growth via endothelial cells. Green-tea-extract (GTE) constituents possess antiangiogenesis properties. We used VEGF to induce human umbilical-vein endothelial cells (HUVECs) and applied GTE, epigallocatechin gallate (EGCG), and mixtures of different compositions of purified catechins (M1 and M2) to evaluate their efficacies of inhibition and their underlying mechanisms using cell-cycle analysis and untargeted metabolomics techniques. GTE, EGCG, M1, and M2 induced HUVEC apoptosis by 22.1 ± 2, 20.0 ± 0.7, 50.7 ± 8.5, and 69.8 ± 4.1%, respectively. GTE exerted a broad, balanced metabolomics spectrum, involving suppression of the biosynthesis of cellular building blocks and oxidative-phosphorylation metabolites as well as promotion of the biosynthesis of membrane lipids and growth factors. M2 mainly induced mechanisms associated with energy and biosynthesis suppression. Therefore, GTE exerted mechanisms involving both promotion and suppression activities, whereas purified catechins induced extensive apoptosis. GTE could be a more promising antineovascularization remedy for ocular treatment.

Induction of Apoptosis in Pterygium Cells by Antagonists of Growth Hormone-Releasing Hormone Receptors.

Purpose: The aim of the study was to investigate the signaling of growth hormone-releasing hormone receptor (GHRH-R) in the pathogenesis of pterygium and determine the apoptotic effect of GHRH-R antagonist on pterygium epithelial cells (PECs). Methods: Fourteen samples of primary pterygium of grade T3 with size of corneal invasion ≥ 4 mm were obtained for investigation by histology, immunofluorescence, electron microscopy, explant culture, and flow cytometry. Results: We found that PECs were localized in the basal layer of the epithelium in advancing regions of the head of pterygium. These cells harbored clusters of rough endoplasmic reticulum, ribosomes, and mitochondria, which were consistent with their aggressive proliferation. Immunofluorescence studies and Western blots showed that GHRH-R and the downstream growth hormone receptor (GH-R) were intensively expressed in PECs. Their respective ligands, GHRH and GH, were also elevated in the pterygium tissues as compared to conjunctival cells. Explanted PECs were strongly immunoreactive to GHRH-R and exhibited differentiation and proliferation that led to lump formation. Treatment with GHRH-R antagonist MIA-602 induced apoptosis of PECs in a dose-dependent manner, which was accompanied by a downregulation of ERK1 and upregulation of Caspase 3 expression. Conclusions: Our results revealed that GHRH-R signaling is involved in survival and proliferation of PECs and suggest a potential therapeutic approach for GHRH-R antagonist in the treatment of pterygium.