Anti-Inflammatory Role of Netrin-4 in Diabetic Retinopathy

Diabetic retinopathy is characterized by dysfunction of the retinal vascular network, combined with a persistent low-grade inflammation that leads to vision-threatening complications. Netrin-4 (NTN4) is a laminin-related secreted protein and guidance cue molecule present in the vascular basal membrane and highly expressed in the retina. A number of studies inferred that the angiogenic abilities of NTN4 could contribute to stabilize vascular networks and modulate inflammation. Analyzing human specimens, we show that NTN4 and netrin receptors are upregulated in the diabetic retina. We further evaluated a knock-out model for NTN4 undergoing experimental diabetes induced by streptozotocin. We investigated retina function and immune cells in vivo and demonstrated that NTN4 provides a protective milieu against inflammation in the diabetic retina and prevents cytokine production.

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Molecular and Pathophysiological Mechanisms of Diabetic Retinopathy in Relation to Adhesion Molecules

Current Diabetes Reviews ◽

10.2174/1573399814666181017103844 ◽

2019 ◽

Vol 15 (5) ◽

pp. 363-371 ◽

Cited By ~ 3

Author(s):

Salini Scaria Joy ◽

Khalid Siddiqui

Keyword(s):

Diabetic Retinopathy ◽

Endothelial Cell ◽

Endothelial Function ◽

Adhesion Molecules ◽

Inflammatory Factors ◽

Low Grade ◽

Pathophysiological Mechanisms ◽

Low Grade Inflammation ◽

Slow Rolling

Diabetic Retinopathy (DR) is considered as a most common microvascular complication of diabetes affected by one in three people who are suffered for diabetes. Several pathophysiological mechanisms and adhesion molecules may play an etiologic role in the development of diabetes and its complications. The adhesion molecules located on both leucocytes and endothelial cells and considered as important molecules which can assessed the endothelial function. The functions of adhesion molecules involved in the cellular margination, slow rolling and transmigration of leukocytes. Hyperglycemia and its immediate biochemical sequelae or the low-grade inflammation directly alter endothelial function or influence endothelial cell functioning indirectly by induce oxidative stress and activates leukocytosis and leukocyte-endothelial cell interactions by the increased expression of adhesion molecules, growth factors, inflammatory factors, chemokines etc. and results DR. This review summarized the several pathophysiological mechanisms and role of adhesion molecules in disruption of homeostasis of vasculature by leukocytes in the development of diabetic retinopathy.

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The Role of Innate Immunity in Osteoarthritis: When Our First Line of Defense Goes On the Offensive

The Journal of Rheumatology ◽

10.3899/jrheum.140382 ◽

2015 ◽

Vol 42 (3) ◽

pp. 363-371 ◽

Cited By ~ 101

Author(s):

Eric W. Orlowsky ◽

Virginia Byers Kraus

Keyword(s):

Immune System ◽

Innate Immune System ◽

Defense Mechanisms ◽

Immune Defense ◽

Innate Immune ◽

Low Grade ◽

Wear And Tear ◽

Low Grade Inflammation

Although osteoarthritis (OA) has existed since the dawn of humanity, its pathogenesis remains poorly understood. OA is no longer considered a “wear and tear” condition but rather one driven by proteases where chronic low-grade inflammation may play a role in perpetuating proteolytic activity. While multiple factors are likely active in this process, recent evidence has implicated the innate immune system, the older or more primitive part of the body’s immune defense mechanisms. The roles of some of the components of the innate immune system have been tested in OA modelsin vivoincluding the roles of synovial macrophages and the complement system. This review is a selective overview of a large and evolving field. Insights into these mechanisms might inform our ability to identify patient subsets and give hope for the advent of novel OA therapies.

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Loss of CD40 attenuates experimental diabetes-induced retinal inflammation but does not protect mice from electroretinogram defects

Visual Neuroscience ◽

10.1017/s0952523817000074 ◽

2017 ◽

Vol 34 ◽

Cited By ~ 5

Author(s):

IVY S. SAMUELS ◽

JOSE-ANDRES C. PORTILLO ◽

YANLING MIAO ◽

TIMOTHY S. KERN ◽

CARLOS S. SUBAUSTE

Keyword(s):

Diabetic Retinopathy ◽

Experimental Diabetes ◽

Low Grade ◽

Retinal Dysfunction ◽

Diabetic Retina ◽

Inflammatory Processes ◽

Retinal Inflammation ◽

Capillary Degeneration ◽

Inflammatory Molecules ◽

Low Grade Inflammation

AbstractChronic low grade inflammation is considered to contribute to the development of experimental diabetic retinopathy (DR). We recently demonstrated that lack of CD40 in mice ameliorates the upregulation of inflammatory molecules in the diabetic retina and prevented capillary degeneration, a hallmark of experimental diabetic retinopathy. Herein, we investigated the contribution of CD40 to diabetes-induced reductions in retinal function via the electroretinogram (ERG) to determine if inflammation plays a role in the development of ERG defects associated with diabetes. We demonstrate that diabetic CD40−/− mice are not protected from reduction to the ERG b-wave despite failing to upregulate inflammatory molecules in the retina. Our data therefore supports the hypothesis that retinal dysfunction found in diabetics occurs independent of the induction of inflammatory processes.

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The Role of Epicardial Adipose Tissue Lymphocytes in Low-Grade Inflammation and Coronary Artery Disease

Diabetes ◽

10.2337/db18-469-p ◽

2018 ◽

Vol 67 (Supplement 1) ◽

pp. 469-P

Author(s):

MILOS MRAZ ◽

ANNA CINKAJZLOVA ◽

ZDENA LACINOVÁ ◽

JANA KLOUCKOVA ◽

HELENA KRATOCHVILOVA ◽

...

Keyword(s):

Coronary Artery Disease ◽

Adipose Tissue ◽

Coronary Artery ◽

Epicardial Adipose Tissue ◽

Low Grade ◽

Artery Disease ◽

Low Grade Inflammation

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Knock out of tmem38b by CRISPR/Cas9 in zebrafish unveils the in vivo role of Trimeric intracellular cation (TRIC) channel B on cell homeostasis

Bone Reports ◽

10.1016/j.bonr.2021.101054 ◽

2021 ◽

Vol 14 ◽

pp. 101054

Author(s):

Laura Leoni ◽

Valentina Daponte ◽

Francesca Tonelli ◽

Roberta Gioia ◽

Silvia Cotti ◽

...

Keyword(s):

Cell Homeostasis ◽

Knock Out

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The Extracellular Small Leucine-Rich Proteoglycan Biglycan Is a Key Player in Gastric Cancer Aggressiveness

Cancers ◽

10.3390/cancers13061330 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1330

Author(s):

Filipe Pinto ◽

Liliana Santos-Ferreira ◽

Marta T. Pinto ◽

Catarina Gomes ◽

Celso A. Reis

Keyword(s):

Clinical Value ◽

Knock Out ◽

Angiogenic Potential ◽

In Vivo Experiments ◽

Cancer Aggressiveness ◽

Advanced Stages ◽

Oncogenic Gene

Biglycan (BGN gene), an extracellular proteoglycan, has been described to be associated with cancer aggressiveness. The purpose of this study was to clarify the clinical value of biglycan as a biomarker in multiple independent GC cohorts and determine the in vitro and in vivo role of biglycan in GC malignant features. We found that BGN is commonly over-expressed in all analyzed cohorts, being associated with disease relapse and poor prognosis in patients with advanced stages of disease. In vitro and in vivo experiments demonstrated that biglycan knock-out GC cells display major phenotypic changes with a lower cell survival, migration, and angiogenic potential when compared with biglycan expressing cells. Biglycan KO GC cells present increased levels of PARP1 and caspase-3 cleavage and a decreased expression of mesenchymal markers. Importantly, biglycan deficient GC cells that were supplemented with exogenous biglycan were able to restore biological features, such as survival, clonogenic and migratory capacities. Our in vitro and in vivo findings were validated in human GC samples, where BGN expression was associated with several oncogenic gene signatures that were associated with apoptosis, cell migration, invasion, and angiogenesis. This study provided new insights on biglycan role in GC that should be taken in consideration as a key cellular regulator with major impact in tumor progression and patients’ clinical outcome.

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Adipose tissue inflammation and metabolic dysfunction: a clinical perspective

Hormone Molecular Biology and Clinical Investigation ◽

10.1515/hmbci-2013-0032 ◽

2013 ◽

Vol 15 (1) ◽

Cited By ~ 2

Author(s):

Charmaine S. Tam ◽

Leanne M. Redman

Keyword(s):

Insulin Resistance ◽

Adipose Tissue ◽

Low Grade ◽

Metabolic Dysfunction ◽

Adipose Tissue Inflammation ◽

Tissue Inflammation ◽

Proinflammatory Mediators ◽

Low Grade Inflammation

AbstractObesity is characterized by a state of chronic low-grade inflammation due to increased immune cells, specifically infiltrated macrophages into adipose tissue, which in turn secrete a range of proinflammatory mediators. This nonselective low-grade inflammation of adipose tissue is systemic in nature and can impair insulin signaling pathways, thus, increasing the risk of developing insulin resistance and type 2 diabetes. The aim of this review is to provide an update on clinical studies examining the role of adipose tissue in the development of obesity-associated complications in humans. We will discuss adipose tissue inflammation during different scenarios of energy imbalance and metabolic dysfunction including obesity and overfeeding, weight loss by calorie restriction or bariatric surgery, and conditions of insulin resistance (diabetes, polycystic ovarian syndrome).

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Multinucleated giant cells in adipose tissue are specialized in adipocyte degradation

10.2337/figshare.13168862 ◽

2020 ◽

Author(s):

Ada Admin ◽

Julia Braune ◽

Andreas Lindhorst ◽

Janine Fröba ◽

Constance Hobusch ◽

...

Keyword(s):

Adipose Tissue ◽

High Fat Diet ◽

Ex Vivo ◽

Giant Cells ◽

Low Grade ◽

Adipose Tissue Macrophages ◽

Visceral Adipose ◽

Low Grade Inflammation

Obesity is associated with a chronic low-grade inflammation in visceral adipose tissue (AT) characterized by an increasing number of adipose tissue macrophages (ATMs) and linked to type 2 diabetes. AT inflammation is histologically indicated by the formation of so-called crown-like structures (CLS), as accumulation of ATMs around dying adipocytes, and the occurrence of multi-nucleated giant cells (MGCs). However to date, the function of MGCs in obesity is unknown. Hence, the aim of this study was to characterize MGCs in AT and unravel the function of these cells. We demonstrate that MGCs occur in obese patients and after 24 weeks of high fat diet (HFD) in mice, accompanying signs of AT inflammation and then represent ~3% of ATMs in mice. Mechanistically, we found evidence that adipocyte death triggers MGC formation. Most importantly, MGCs in obese AT have a higher capacity to phagocytose oversized particles, such as adipocytes, as shown by live-imaging of AT, 45 µm bead uptake ex vivo and a higher lipid content in vivo. Finally, we show that IL-4 treatment is sufficient to increase the number of MGCs in AT, whereas other factors maybe more important for endogenous MGC formation in vivo.

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Osteopontin Expression in Human and Murine Obesity: Extensive Local Up-Regulation in Adipose Tissue but Minimal Systemic Alterations

Endocrinology ◽

10.1210/en.2007-1312 ◽

2007 ◽

Vol 149 (3) ◽

pp. 1350-1357 ◽

Cited By ~ 94

Author(s):

Florian W. Kiefer ◽

Maximilian Zeyda ◽

Jelena Todoric ◽

Joakim Huber ◽

René Geyeregger ◽

...

Keyword(s):

Insulin Resistance ◽

Adipose Tissue ◽

Plasma Concentrations ◽

Morbidly Obese ◽

Low Grade ◽

Obese Patients ◽

Multifunctional Protein ◽

Inflammatory Processes ◽

Low Grade Inflammation

Obesity is associated with a chronic low-grade inflammation characterized by macrophage infiltration of adipose tissue (AT) that may underlie the development of insulin resistance and type 2 diabetes. Osteopontin (OPN) is a multifunctional protein involved in various inflammatory processes, cell migration, and tissue remodeling. Because these processes occur in the AT of obese patients, we studied in detail the regulation of OPN expression in human and murine obesity. The study included 20 morbidly obese patients and 20 age- and sex-matched control subjects, as well as two models (diet-induced and genetic) of murine obesity. In high-fat diet-induced and genetically obese mice, OPN expression was drastically up-regulated in AT (40 and 80-fold, respectively) but remained largely unaltered in liver (<2-fold). Moreover, OPN plasma concentrations remained unchanged in both murine models of obesity, suggesting a particular local but not systemic importance for OPN. OPN expression was strongly elevated also in the AT of obese patients compared with lean subjects in both omental and sc AT. In addition, we detected three OPN isoforms to be expressed in human AT and, strikingly, an obesity induced alteration of the OPN isoform expression pattern. Analysis of AT cellular fractions revealed that OPN is exceptionally highly expressed in AT macrophages in humans and mice. Moreover, OPN expression in AT macrophages was strongly up-regulated by obesity. In conclusion, our data point toward a specific local role of OPN in obese AT. Therefore, OPN could be a critical regulator in obesity induced AT inflammation and insulin resistance.

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