Mechanistic Insights into Immunological Therapy for Targeting Diabetic Retinopathy

2021 ◽  
Vol 5 (3) ◽  
pp. 01-05
Author(s):  
Imteyaz Qamar

Diabetic retinopathy (DR) is a common complication amongst patients that have diabetes. It is a leading cause of blindness in middle age people. A large proportion of patients who have diabetes develop retinopathy. There are several immunological reasons associated with the pathophysiology of this disease. Role of several mediators that increase the oxidative stress and have a pro-inflammatory effect which leads to capillary occlusion and neovascularization (NV). Increased vasopermeability due to disruption of the blood-retinal barrier (BRB) leading to diabetic macular edema (DME). Immunotherapies utilise different compounds and target various inflammatory molecules like TNF-α and pathways such as PPARγ for treatment of this progressive disease. Inflammatory and pro-inflammatory pathways are found to have an essential role in promoting DR; therefore, targeting them provides a useful technique for curing DR.

2021 ◽  
Vol 5 (3) ◽  
pp. 01-05
Author(s):  
Imteyaz Qamar

Diabetic retinopathy (DR) is a common complication amongst patients that have diabetes. It is a leading cause of blindness in middle age people. A large proportion of patients who have diabetes develop retinopathy. There are several immunological reasons associated with the pathophysiology of this disease. Role of several mediators that increase the oxidative stress and have a pro-inflammatory effect which leads to capillary occlusion and neovascularization (NV). Increased vasopermeability due to disruption of the blood-retinal barrier (BRB) leading to diabetic macular edema (DME). Immunotherapies utilise different compounds and target various inflammatory molecules like TNF-α and pathways such as PPARγ for treatment of this progressive disease. Inflammatory and pro-inflammatory pathways are found to have an essential role in promoting DR; therefore, targeting them provides a useful technique for curing DR.


2007 ◽  
Vol 4 (3_suppl) ◽  
pp. S9-S11 ◽  
Author(s):  
Paul M Dodson

Diabetic eye disease is the major cause of blindness and vision loss among working-age people in developed countries. Microangiopathy and capillary occlusion underlie the pathogenesis of disease. While laser treatment is regarded as the standard therapy, intensive medical management of glycaemia and hypertension is also a priority in order to reduce the risk of diabetic retinopathy. Recent data have prompted a re-evaluation of the role of lipid-modifying therapy in reducing diabetic retinopathy. The Fenofibrate Intervention for Event Lowering in Diabetes (FIELD) study demonstrated a significant 30% relative reduction in the need for first retinal laser therapy in patients with (predominantly early-stage) type 2 diabetes treated with fenofibrate 200 mg daily, from 5.2% with placebo to 3.6% with fenofibrate, p=0.0003. The benefit of fenofibrate was evident within the first year of treatment. These promising data justify further evaluation of the mechanism and role of fenofibrate, in addition to standard therapy, in the management of diabetic retinopathy.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 435-435
Author(s):  
Tripti Kumari ◽  
Jing Li ◽  
Andrew Barazia, ◽  
Vishwanath Jha ◽  
Amber Hansch ◽  
...  

Abstract The interaction between neutrophils and endothelial cells (ECs) is critical for the pathogenesis of vascular inflammation. Neutrophil recruitment to inflamed tissues is initiated by rolling on activated ECs through the interactions between P-/E-selectins and their ligands. Subsequently, activated integrins (mainly αLβ2 and αMβ2) and chemokine receptors bind to their ligands on ECs and mediate slow-rolling, adhesion, crawling, and transmigration of neutrophils. Although many neutrophil adhesion receptors have been identified, the regulation of their ligand-binding function remains not fully understood. Using real-time intravital microscopy with mice lacking downstream regulatory element antagonist modulator (DREAM) and their bone marrow chimeric mice, we demonstrated that hematopoietic cell DREAM contributes to neutrophil recruitment to sites of vascular inflammation induced by TNF-α- but not a G protein-coupled receptor ligand, MIP-2 or fMLP. Our studies using adoptive neutrophil transfers and flow chamber assays revealed that neutrophil DREAM positively regulates the neutrophil recruitment processes under TNF-α-induced inflammatory conditions. Using RNA-seq and biochemical and cell biological studies, we found that neutrophil DREAM upregulates numerous pro-inflammatory molecules and down-regulates anti-inflammatory molecules after TNF-α treatment. In particular, neutrophil DREAM repressed expression of A20, a negative regulator of NF-κB signaling, and enhanced phosphorylation of IκB kinase (IKK) in response to TNF-α, suggesting the role of neutrophil DREAM in NF-κB activity. Furthermore, we observed that DREAM deletion and IKK inhibition significantly diminishes the ligand-binding activity of β2 integrins in neutrophils after short-term treatment with TNF-α and that deletion of neutrophil DREAM does not affect the expression of other neutrophil adhesion receptors, such as PSGL-1, L-selectin, CD44, CXCR2, and CXCR4. As assessed by flow cytometry using conformation-specific reporter antibodies, knockdown of DREAM in neutrophil-like HL-60 cells decreased TNF-α-induced activation of β2 integrins. Neutrophil DREAM promoted degranulation through IKK-mediated SNAP-23 phosphorylation after short-term treatment with TNF-α, implying the role of neutrophil DREAM-IKK signaling in NF-κB-independent signaling. Using intravital microscopy with Berkeley mice (a mouse model of sickle cell disease) deficient in hematopoietic or nonhematopoietic DREAM, we demonstrated that hematopoietic cell DREAM is crucial for inducing intravascular cell-cell aggregation and vaso-occlusive events in microvessels following the TNF-α challenge. Furthermore, infusion of DREAM KO neutrophils, compared with WT neutrophils, significantly reduced neutrophil recruitment and vaso-occlusive events in TNF-α-challenged SCD mice. These results demonstrate that neutrophil DREAM positively regulates β2 integrin function and promotes neutrophil recruitment during sterile inflammation via NF-κB-dependent and independent mechanisms. Our study provides evidence that targeting DREAM might be a novel therapeutic strategy to reduce excessive neutrophil recruitment in inflammatory diseases. Disclosures No relevant conflicts of interest to declare.


2021 ◽  
Vol 11 ◽  
Author(s):  
Mariaelena Filippelli ◽  
Giuseppe Campagna ◽  
Pasquale Vito ◽  
Tiziana Zotti ◽  
Luca Ventre ◽  
...  

Purpose: To determine the levels of pro-inflammatory cytokines and soluble mediators (TNF-α, IL6, IL2, and PDGF-AB) in 28 vitreous biopsies taken from patients with proliferative diabetic retinopathy (PDR) and treated with increasing doses of curcumin (0. 5 and 1 μM), with or without homotaurine (100 μM) and vitamin D3 (50 nM).Materials and Methods: ELISA tests were performed on the supernatants from 28 vitreous biopsies that were incubated with bioactive molecules at 37°C for 20 h. The concentration of the soluble mediators was calculated from a calibration curve and expressed in pg/mL. Shapiro-Wilk test was used to verify the normality of distribution of the residuals. Continuous variables among groups were compared using the General Linear Model (GLM). Homoscedasticity was verified using Levene and Brown-Forsythe tests. Post-hoc analysis was also performed with the Tukey test. A p ≤ 0.05 was considered statistically significant.Results: The post-hoc analysis revealed statistically detectable changes in the concentrations of TNF-α, IL2, and PDGF-AB in response to the treatment with curcumin, homotaurine, and vitamin D3. Specifically, the p-values for between group comparisons are as follows: TNF-α: (untreated vs. curcumin 0.5 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.008, (curcumin 0.5 μM vs. curcumin 0.5 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.0004, (curcumin 0.5 μM vs. curcumin 1 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.02, (curcumin 1 μM vs. curcumin 0.5 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.025, and (homotaurine 100 μM + vitamin D3 50 nM vs. curcumin 0.5 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.009; IL2: (untreated vs. curcumin 0.5 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.0023, and (curcumin 0.5 μM vs. curcumin 0.5 μM+ homotaurine 100 μM + vitamin D3 50 nM) p = 0.0028; PDGF-AB: (untreated vs. curcumin 0.5 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.04, (untreated vs. curcumin 1 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.0006, (curcumin 0.5 μM vs. curcumin 1 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.006, and (homotaurine 100 μM + vitamin D3 50 nM vs. curcumin 1 μM + homotaurine 100 μM + vitamin D3 50 nM) p = 0.022. IL6 levels were not significantly affected by any treatment.Conclusions: Pro-inflammatory cytokines are associated with inflammation and angiogenesis, although there is a discrete variability in the doses of the mediators investigated among the different vitreous samples. Curcumin, homotaurine, and vitamin D3 individually have a slightly appreciable anti-inflammatory effect. However, when used in combination, these substances are able to modify the average levels of the soluble mediators of inflammation and retinal damage. Multi-target treatment may provide a therapeutic strategy for diabetic retinopathy in the future.Clinical Trial Registration : The trial was registered at clinical trials.gov as NCT04378972 on 06 May 2020 (“retrospectively registered”) https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid = S0009UI8&selectaction = Edit&uid = U0003RKC&ts = 2&cx = dstm4o.


PPAR Research ◽  
2008 ◽  
Vol 2008 ◽  
pp. 1-4 ◽  
Author(s):  
Yasuo Yanagi

The retinal vessels have two barriers: the retinal pigment epithelium and the retinal vascular endothelium. Each barrier exhibits increased permeability under various pathological conditions. This condition is referred to as blood retinal barrier (BRB) breakdown. Clinically, the most frequently encountered condition causing BRB breakdown is diabetic retinopathy. In recent studies, inflammation has been linked to BRB breakdown and vascular leakage in diabetic retinopathy. Biological support for the role of inflammation in early diabetes is the adhesion of leukocytes to the retinal vasculature (leukostasis) observed in diabetic retinopathy. is a member of a ligand-activated nuclear receptor superfamily and plays a critical role in a variety of biological processes, including adipogenesis, glucose metabolism, angiogenesis, and inflammation. There is now strong experimental evidence to support the theory that inhibits diabetes-induced retinal leukostasis and leakage, playing an important role in the pathogenesis of diabetic retinopathy. Therapeutic targeting of may be beneficial to diabetic retinopathy.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1353.1-1355
Author(s):  
S. J. Yoo ◽  
S. W. Kang ◽  
J. Kim ◽  
I. S. Yoo ◽  
C. K. Park ◽  
...  

Background:Rheumatoid arthritis (RA) is a progressive, chronic inflammatory autoimmune disease. Pro-inflammatory molecules, activated lymphocytes, and the migration of inflammatory cells are important in the development of RA. There are many unknown causes of RA. And there are many patients who are refractory to treatment with known disease-modifying anti-rheumatic drugs. So, unknown cause of RA needs to be elucidated.CD70 is a member of the tumor necrosis factor (TNF) superfamily and a ligand for CD27. The interaction of CD70 with its receptor CD27 promotes expansion and differentiation of memory and effector T cells as well as B-cell expansion and plasma cell differentiation. Hypoxia is an important micro-environmental factor in RA synovium. Hypoxia induces activation of hypoxia inducible factor (HIF). The expression of HIF-2α is up-regulated in human RA synovium. Reactive oxygen species (ROS) has been implicated in the pathophysiology of RA.Objectives:In this study, we tried to examine the presence of CD70 in RA synovium and investigate the role of CD70 in the development of RA associated with HIF-2α and ROS.Methods:Fibroblast-like synoviocyte (FLS), peripheral blood (PB) and synovial fluid (SF) were used for experiments. FLS was stimulated with recombinant human (rh)-IL-17 and rh-TNF-α. N-acetyl-L-cysteine (NAC) was used as a ROS scavenger. HIF-2α inhibitor (PT-2385) was used for examine the effect of HIF-2α in RA-FLS. RT-PCR, qPCR, western blotting, flow-cytometry, ELISA, cell migration assay, and scratch wound assay were performed.Results:CD70 mRNA is present and elevated by stimulation with IL-17 and TNF-α in both RA-FLS and osteoarthritis (OA)-FLS (Fig 1). CD70 also expresses on the surface of RA-FLS and OA FLS (Fig 2). CD70 expression on the surface of FLS is elevated by stimulation with IL-17 and TNF-α in both RA and OA. Soluble CD27 is present higher in the supernatant of RA-SF than OA-SF (Fig 3). HIF-2α mRNA, HIF-2α protein, and the amount of ROS were all elevated after treatment with IL-17 and TNF-α in RA-FLS (Fig 4, Fig 5). CD70 expression and the amount of ROS were lowered by treatment with HIF-2α inhibitor in RA-FLS (Fig 6). Decreased amount of ROS results in decreased CD70 expression on the RA-FLS (Fig 7). CD70 influenced on cell migration directly or by HIF-2α (Fig 8).Conclusion:In this study, we found the function of CD70 in RA-FLS associated with HIF-2α and ROS. First, CD70 on RA-FLS interacts with CD27 in the RA-SF and this interaction produces sCD27 (Fig. 9) and CD70 has an influence on the migration of RA-FLS. Second, IL-17 and TNF-α are critical factors to trigger the expression of CD70, HIF-2α and ROS in RA synovium. Third, CD70 is regulated by HIF-2α associated with ROS. From these results, we suggest that CD70 may be a new therapeutic target of RA. And sCD27 also may be an important diagnostic maker of RA.References:[1]Lundy SK, Sarkar S, Tesmer LA, Fox DA. Cells of the synovium in rheumatoid arthritis. T lymphocytes. Arthritis Res Ther. 2007;9(1):202.[2]Nevius E, Gomes AC, Pereira JP. Inflammatory Cell Migration in Rheumatoid Arthritis: A Comprehensive Review. Clin Rev Allergy Immunol. 2016;51(1):59-78.[3]Bowman MR, Crimmins MA, Yetz-Aldape J, Kriz R, Kelleher K, Herrmann S. The cloning of CD70 and its identification as the ligand for CD27. J Immunol. 1994;152(4):1756-61.[4]Kitajima S, Lee KL, Fujioka M, Sun W, You J, Chia GS, et al. Hypoxia-inducible factor-2 alpha up-regulates CD70 under hypoxia and enhances anchorage-independent growth and aggressiveness in cancer cells. Oncotarget. 2018;9(27):19123-35.[5]Gaber T, Dziurla R, Tripmacher R, Burmester GR, Buttgereit F. Hypoxia inducible factor (HIF) in rheumatology: low O2! See what HIF can do! Ann Rheum Dis. 2005;64(7):971-80.Disclosure of Interests:None declared


2020 ◽  
Vol 10 (6-s) ◽  
pp. 122-124
Author(s):  
Ekawaty Suryani Mastari ◽  
Sry Suryani Widjaja ◽  
Yahwardiah Siregar ◽  
Mutiara Indah Sari

Diabetic retinopathy is a common neurovascular complication of diabetic that strike a third of diabetic patients worldwide. Complex mechanism of biomolecules including enzyme and cytokines is related to oxidative stress of constant hyperglycaemia. Vascular permeability damage resulting from endothelial leakage and apoptosis of Muller cell is the main mechanism of retinal damage.  MMPs as endopeptidases have an important role in angiogenesis process of retinopathy by working with various molecules of growth factors, chemokines, cytokines and cell adhesion molecules. MMP-9 has been widely shown to be associated with inflammation, blood-retinal barrier disruption, cell apoptosis and neovascularization in the diabetic retinopathy pathomechanism. Keywords: Diabetic retinopathy; MMP; MMP-9; Blood-retinal barrier


2020 ◽  
Author(s):  
Joséphine Lantoine ◽  
Anthony Procès ◽  
Agnès Villers ◽  
Sophie Halliez ◽  
Luc Buée ◽  
...  

AbstractTraumatic brain injury (TBI) remains one of the leading causes of mortality and morbidity worldwide. Despite its high prevalence and extensive efforts to develop neuroprotective therapies, effective treatments for TBI are still limited. Among important neuronal damages, TBI induces structural and functional alterations of astrocytes, the most abundant cell type in the brain. Injured astrocytes respond in diverse mechanisms that result in reactive astrogliosis and are involved in the physiopathological mechanisms of TBI in an extensive and sophisticated manner. The establishment of effective neuroprotective treatments for TBI requires to better understand the complex biochemical interactions between activated astrocytes and neurons that contribute to the secondary injury. To address this challenge, we studied in vitro the role of mechanically injured astrocytes on the growth and synaptic connections of cortical neuronal networks of controlled architectures grown on well-defined protein micropatterns. Astrocytes were cultivated on elastic membranes and mechanically activated by stretching cycles. The culture media of healthy or activated astrocytes was then introduced on neuronal networks. We analyzed the neuronal viability, the neurite growth and the synaptic density of neuronal networks to understand the role of the inflammatory molecules secreted by mechanically activated astrocytes. Furthermore, we cultivated neuronal networks during 13 days with different doses of TNF-α in order to decipher its individual contribution among the other cytokines. Here we show that the ratio of tubulin to synapsin area was significantly higher in neuronal networks treated with either 4 or 2 doses of TNF-α, suggesting that TNF-α can promote the tubulin polymerization process. Assuming that TNF-α can bind to either TNFR1 or TNFR2 receptors, which lead respectively to the cell survival or the cell apoptosis, we studied the modulation of the both TNF-α receptors in response to the medium of mechanically activated astrocytes and different doses of TNF-α. Our findings indicate that the amount of both receptors increases with the maturation of the network. In addition, we observed a significant modulation of the amount of TNFR1 and TNFR2 in response to the media of injured astrocytes that leads to a large imbalance between both receptors, suggesting an important role for TNFα-signaling in the physiopathological mechanisms of TBI.


PLoS ONE ◽  
2014 ◽  
Vol 9 (10) ◽  
pp. e108508 ◽  
Author(s):  
Sampathkumar Rangasamy ◽  
Paul G. McGuire ◽  
Carolina Franco Nitta ◽  
Finny Monickaraj ◽  
Sreenivasa R. Oruganti ◽  
...  

2020 ◽  
Vol 28 (1) ◽  
pp. 80-92
Author(s):  
Zakia Akter ◽  
Faiza Rafa Ahmed ◽  
Mousumi Tania ◽  
Md. Asaduzzaman Khan

Background: : Thymoquinone is a promising anticancer molecule, the chemopreventive role of which is well-known at least in vitro and in the animal model. In this review article, we focused on the anti-inflammatory activities of thymoquinone in cancer cells. Method:: Research data on inflammation, cancer and thymoquinone were acquired from PubMed, Scopus, Web of Science and Google Scholar. We reviewed papers published since the mid of the last century, and the most cited papers of the last ten years. Results:: Studies indicate that thymoquinone possesses immunomodulatory activities, in addition to its chemopreventive role, as thymoquinone can target and modulate inflammatory molecules, like nuclear factor kappa B (NF-κβ), interleukins, tumor necrosis factor-α (TNF-α), and certain growth factors. As chronic inflammation plays an important role in cancer development, controlling inflammatory pathways is an important mechanism of an anticancer molecule, and modulation of inflammatory pathways might be one of the key mechanisms of thymoquinone’s anticancer activities. Conclusion: : This article reviewed the role of inflammation on cancer development, and the action of thymoquinone on inflammatory molecules, which have been proved in vitro and in vivo. Much attention is required for studying the role of thymoquinone in immunotherapeutics and developing this molecule as a future anticancer drug.


Sign in / Sign up

Export Citation Format

Share Document