Anti-inflammatory effects of α-MSH through p-CREB expression in sarcoidosis like granuloma model

Evolutionarily conserved mechanisms regulating stress-induced neutrophil redistribution in fish

Introduction

Stress may pose a serious challenge to immune homeostasis. Stress however also may prepare the immune system for challenges such as wounding or infection, which are likely to happen during a fight or flight stress response.

Methods

In common carp (Cyprinus carpio L.) we studied the stress-induced redistribution of neutrophils into circulation, and the expression of genes encoding CXC chemokines known to be involved in the regulation of neutrophil retention (CXCL12) and redistribution (CXCL8), and their receptors (CXCR4 and CXCR1-2, respectively) in blood leukocytes and in the fish hematopoietic organ - the head kidney. The potential involvement of CXC receptors and stress hormone receptors in stress-induced neutrophil redistribution was determined by an in vivo study with selective CXCR inhibitors and antagonists of the receptors involved in stress regulation: glucocorticoid/mineralocorticoid receptors (GRs/MRs), adrenergic receptors (ADRs) and the melanocortin 2 receptor (MC2R).

Results

The stress-induced increase of blood neutrophils was accompanied by a neutrophil decrease in the hematopoietic organs. This increase was cortisol-induced and GR-dependent. Moreover, stress upregulated the expression of genes encoding CXCL12 and CXCL8 chemokines, their receptors, and the receptor for granulocytes colony-stimulation factor (GCSFR) and matrix metalloproteinase 9 (MMP9). Blocking of the CXCR4 and CXCR1 and 2 receptors with selective inhibitors inhibited the stress-induced neutrophil redistribution and affected the expression of genes encoding CXC chemokines and CXCRs as well as GCSFR and MMP9.

Discussion

Our data demonstrate that acute stress leads to the mobilization of the immune system, characterized by neutrophilia. CXC chemokines and CXC receptors are involved in this stress-induced redistribution of neutrophils from the hematopoietic tissue into the peripheral blood. This phenomenon is directly regulated by interactions between cortisol and the GR/MR. Considering the pivotal importance of neutrophilic granulocytes in the first line of defense, this knowledge is important for aquaculture, but will also contribute to the mechanisms involved in the stress-induced perturbation in neutrophil redistribution as often observed in clinical practice.

Acthar® Gel Treatment for Patients with Autoimmune and Inflammatory Diseases: An Historical Perspective and Characterization of Clinical Evidence

Acthar® Gel (repository corticotropin injection) is a naturally sourced complex mixture of adrenocorticotropic hormone analogs and other pituitary peptides that is believed to have both steroidogenic and nonsteroidogenic immunomodulatory effects via activation of melanocortin receptors in various cells throughout the body. Since 1952, Acthar has been approved by the US Food and Drug Administration to treat a variety of autoimmune and inflammatory diseases. Since 2014, Mallinckrodt Pharmaceuticals has conducted a large number of preclinical, clinical, and real-world-evidence studies of Acthar for the treatment of rheumatoid arthritis, systemic lupus erythematosus, dermatomyositis and polymyositis, multiple sclerosis relapse, ophthalmic disorders, sarcoidosis, and nephrotic syndrome. To date, Acthar has been the subject of more than 500 publications, many of which demonstrate the safety and efficacy of Acthar in patients with inflammatory diseases for whom standard treatments were ineffective or intolerable. Here, we review the history of Acthar and the findings of studies that have investigated the mechanism of action, safety, efficacy, and real-world effectiveness of Acthar for the treatment of inflammatory diseases.

Pulmonary Sarcoidosis: Experimental Models and Perspectives of Molecular Diagnostics Using Quantum Dots

Sarcoidosis is a complex inflammatory multisystem disease of unknown etiology that is characterised by epithelioid cell granulomatous lesions affecting various organs, mainly the lungs. In general, sarcoidosis is asymptomatic, but some cases result in severe complications and organ failure. So far, no accurate and validated modelling for clinical and pathohistological manifestations of sarcoidosis is suggested. Moreover, knowledge about disease-specific diagnostic markers for sarcoidosis is scarce. For instance, pulmonary granulomatosis is associated with the upregulated production of proinflammatory molecules: TNF-α, IL-6, CXCL1, CCL2, CCL18, CD163, serum angiotensin-converting enzyme (sACE), lysozyme, neopterin, and serum amyloid A (SAA). Quantum dots (QDs) are widely applied for molecular diagnostics of various diseases. QDs are semiconductor nanoparticles of a few nanometres in size, made from ZnS, CdS, ZnSe, etc., with unique physical and chemical properties that are useful for the labelling and detection in biological experiments. QDs can conjugate with various antibodies or oligonucleotides, allowing for high-sensitivity detection of various targets in organs and cells. Our review describes existing experimental models for sarcoidosis (in vitro, in vivo, and in silico), their advantages and restrictions, as well as the physical properties of quantum dots and their potential applications in the molecular diagnostics of sarcoidosis. The most promising experimental models include mice with TSC2 deletion and an in silico multiscale computational model of sarcoidosis (SarcoidSim), developed using transcriptomics and flow cytometry of human sarcoid biopsies. Both models are most efficient to test different candidate drugs for sarcoidosis.

Results From a Phase 4, Multicenter, Randomized, Double-Blind, Placebo-Controlled Study of Repository Corticotropin Injection for the Treatment of Pulmonary Sarcoidosis

INTRODUCTION

Long-term treatment of pulmonary sarcoidosis with glucocorticoids has been associated with toxicity and other adverse events, highlighting the need for alternative therapies. The goal of this study was to evaluate the efficacy and safety of repository corticotropin injection (RCI, Acthar^® Gel) in patients with pulmonary sarcoidosis and to validate endpoints for use in future clinical trials.

METHODS

In this multicenter, randomized, placebo-controlled trial, subjects received subcutaneous RCI (80 U) twice weekly or matching placebo through 24 weeks in a double-blind treatment phase, followed by an optional 24-week open-label extension. Efficacy was measured by glucocorticoid tapering, pulmonary function tests, chest imaging, patient-reported outcomes, and a novel sarcoidosis treatment score (STS). Safety was assessed by adverse events, physical examinations, vital signs, clinical laboratory abnormalities, and imaging. The study was terminated early due to low enrollment caused by the COVID-19 pandemic, thereby precluding statistical analysis.

RESULTS

Fifty-five subjects were randomized to receive either RCI (n = 27) or placebo (n = 28). Mean STS at week 24 showed greater improvement with RCI (1.4) compared with placebo (0.7). At week 48, those who remained on RCI had an STS of 1.8 compared with 0.9 in those who switched from placebo to RCI. More subjects in the RCI group discontinued glucocorticoids at week 24 compared to the placebo group. Glucocorticoid discontinuation was comparable at week 48 for those who switched from placebo to RCI and those who continued RCI. Similar trends in favor of RCI over placebo were observed with the other efficacy endpoints. No new or unexpected safety signals were identified.

CONCLUSIONS

RCI was safe and well tolerated, with trends in efficacy data suggesting greater improvement with RCI compared to placebo in patients receiving standard-of-care therapy for pulmonary sarcoidosis. The study also provided validation of efficacy endpoints that may be used in larger trials for pulmonary sarcoidosis.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03320070.

Anti-Melanogenesis Effects of a Cyclic Peptide Derived from Flaxseed via Inhibition of CREB Pathway

Linosorbs (Los) are cyclic peptides from flaxseed oil composed of the LO mixture (LOMIX). The activity of LO has been reported as being anti-cancer and anti-inflammatory. However, the study of skin protection has still not proceeded. In particular, there are poorly understood mechanisms of melanogenesis to LO. Therefore, we investigated the anti-melanogenesis effects of LOMIX and LO, and its activity was examined in mouse melanoma cell lines. The treatment of LOMIX (50 and 100 μg/mL) and LO (6.25-50 μM) suppressed melanin secretion and synthesis, which were 3-fold increased, in a dose-dependent manner, up to 95%. In particular, [1-9-NαC]-linusorb B3 (LO1) and [1-9-NαC]-linusorb B2 (LO2) treatment (12.5 and 25 μM) highly suppressed the synthesis of melanin in B16F10 cell lines up to 90%, without toxicity. LOMIX and LOs decreased the 2- or 3-fold increased mRNA levels, including the microphthalmia-associated transcription factor (MITF), Tyrosinase, tyrosinase-related protein 1 (TYRP1), and tyrosinase-related protein 2 (TYRP2) at the highest concentration (25 μM). Moreover, the treatment of 25 μM LO1 and LO2 inhibited the expression of MITF and phosphorylation of upper regulatory proteins such as CREB and PKA. Taken together, these results suggested that LOMIX and its individual LO could inhibit melanin synthesis via downregulating the CREB-dependent signaling pathways, and it could be used for novel therapeutic materials in hyperpigmentation.

Anti-inflammatory Properties of the Alpha-Melanocyte-Stimulating Hormone in Models of Granulomatous Inflammation

Purpose

Alpha-melanocyte stimulating hormone (α-MSH) is known to have anti-inflammatory effects. However, the anti-inflammatory properties of α-MSH on normal bronchial epithelial cells are largely unknown, especially in the context of in vitro sarcoidosis models.

Methods

We evaluated the anti-inflammatory effects of α-MSH on two different in vitro sarcoidosis models (lung-on-membrane model; LOMM and three-dimensional biochip pulmonary sarcoidosis model; 3D-BSGM) generated from NBECs and an in vivo sarcoidosis mouse model.

Results

Treatment with α-MSH decreased inflammatory cytokine levels and downregulated type I interferon pathway genes and related proteins in LOMM and 3D-BSGM models. Treatment with α-MSH also significantly decreased macrophages and cytotoxic T-cells counts in a sarcoidosis mice model.

Conclusion

Our results confirm the direct role of type I IFNs in the pathogenesis of sarcoid lung granulomas and highlight α-MSH as a potential novel therapeutic agent for treating pulmonary sarcoidosis.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00408-022-00546-x.

Emerging insights in sarcoidosis: moving forward through reverse translational research

Sarcoidosis is a chronic granulomatous disease of unknown etiology that primarily affects the lungs. The development of stage IV or fibrotic lung disease accounts for a significant proportion of the morbidity and mortality attributable to sarcoidosis. Further investigation into the active mechanisms of disease pathogenesis and fibrogenesis might illuminate fundamental mediators of injury and repair while providing new opportunities for clinical intervention. However, progress in sarcoidosis research has been hampered by the heterogeneity of clinical phenotypes and the lack of a consensus modeling system. Recently, reverse translational research, wherein observations made at the patient level catalyze hypothesis-driven research at the laboratory bench, has generated new discoveries regarding the immunopathogenic mechanisms of pulmonary granuloma formation, fibrogenesis, and disease model development. The purpose of this review is to highlight the promise and possibility of these novel investigative efforts.

Assessment of Experimental Techniques That Facilitate Human Granuloma Formation in an In Vitro System: A Systematic Review

The process of granuloma formation is complex, and due to species differences, the validity of animal studies is somewhat questioned. Moreover, the large number of animals needed to observe the different stages of development also raises ethical questions. Therefore, researchers have explored the use of human peripheral blood mononuclear cells (PBMCs), a heterogeneous population of immune cells, in an in vitro model. This review included in vitro studies that focused on exposing PBMCs—from healthy, sensitized, or diseased individuals—to antigens derived from infectious agents—such as mycobacteria or Schistosoma spp.—or inorganic antigens—such as beryllium. The reviewed studies mainly explored how human in vitro granuloma models can contribute towards understanding the pathogenesis of granulomatous diseases, especially during the early stages of granuloma formation. The feasibility of granuloma modelling was thus largely assessed via experimental techniques including (1) granuloma scoring indices (GI), (2) cell surface markers and (3) cytokine secretion profiling. While granuloma scoring showed some similarities between studies, a large variability of culture conditions and endpoints measured have been identified. The lack of any standardization currently impedes the success of a human in vitro granuloma model.

Repository Corticotropin Injection for the Treatment of Pulmonary Sarcoidosis: A Narrative Review

Although corticosteroids are the standard first-line therapy for pulmonary sarcoidosis, long-term and high-dose use of these drugs are associated with increased risk of adverse events and high healthcare utilization costs. Treatment guidelines for pulmonary sarcoidosis indicate that off-label immunomodulators and biologics may be warranted for severe disease. Repository corticotropin injection (RCI, Acthar^® Gel), a complex mixture of adrenocorticotropic hormone analogs and other pituitary peptides, is one of only two therapies approved by the US Food and Drug Administration for symptomatic pulmonary sarcoidosis and is recommended by current European Respiratory Society treatment guidelines for use on a case-by-case basis. With its unique anti-inflammatory and immunomodulatory mechanism of action through activation of melanocortin receptors in various cell types, RCI has demonstrated steroid-sparing properties. RCI has a long history of use in autoimmune and inflammatory disorders, with proven safety and efficacy for pulmonary sarcoidosis. In this narrative review, we present the clinical evidence for the safety and efficacy of RCI in the treatment of pulmonary sarcoidosis, identify where RCI falls within the current treatment guidelines, and describe the unique mechanism of action of RCI for promoting anti-inflammatory and immunomodulatory effects.

Translational advances of melanocortin drugs: Integrating biology, chemistry and genetics

Melanocortin receptors have emerged as important targets with a very unusual versatility, as their widespread distribution on multiple tissues (e.g. skin, adrenal glands, brain, immune cells, exocrine glands) together with the variety of physiological processes they control (pigmentation, cortisol release, satiety mechanism, inflammation, secretions), place this family of receptors as genuine therapeutic targets for many disorders. This review focuses in the journey of the development of melanocortin receptors as therapeutic targets from the discovery of their existence in the early 1990 s to the approval of the first few drugs of this class. Two major areas of development characterise the current state of melanocortin drug development: their role in obesity, recently culminated with the approval of setmelanotide, and their potential for the treatment of chronic inflammatory and autoimmune diseases like rheumatoid arthritis, multiple sclerosis or fibrosis. The pro-resolving nature of these drugs offers the advantage of acting by mimicking the way our body naturally resolves inflammation, expecting fewer side effects and a more balanced (i.e. non-immunosuppressive) response from them. Here we also review the approaches followed for the design and development of novel compounds, the importance of the GPCR nature of these receptors in the process of drug development, therapeutic value, current challenges and successes, and the potential for the implementation of precision medicine approaches through the incorporation of genetics advances.

α- MSH plays anti-inflammatory and anti-fungal role in Aspergillus Fumigatus keratitis

PURPOSE

To investigate the anti-inflammatory and anti-fungal role of α-melanocyte stimulating hormone (α-MSH) in Aspergillus Fumigatus (A. fumigatus) keratitis.

METHOD

Corneas of C57BL/6 mice were infected with A. Fumigatus. α-MSH (5 ul, 1x10^-4mmol/ml) was given by subconjunctival injection from day 1 to day 3 post infection (p.i.). After 3 days p.i., clinical score was recored and HE staining was tested. Fungal load in mice corneas was observed by plate counting. Pro-inflammatory mediators and pattern recognition receptors (PRRs) were detected. The numbers of neutrophils and macrophages were tested by immunofluorescence staining. The role of α-MSH in RAW264.7 cells after A. fumigatus stimulation were evaluated by PCR and Western blot, and MPKA protein levels including total-JNK (T-JNK), phosphorylated-JNK (P-JNK), total-ERK (T-ERK) and phosphorylated-ERK (P-ERK) were tested via Western blot with or without α-MSH treatment.

RESULTS

Compared with PBS control group, α-MSH treatment alleviated disease response and decreased clinical score at 3 days p.i. HE staining showed less infiltration in corneal tissue after α-MSH treatment. Plate counting experiment showed that number of viable fungus in corneas of α-MSH treated group was less than control group. mRNA levels of IL-1β, TNF-α, IL-6, MIP-2, LOX-1, Dectin-1 and iNOS were decreased. Protein levels of IL-1β, TNF-α, IL-6 and Dectin-1 were decreased. α-MSH treatment also decreased the infiltrating neutrophils and macrophages. The levels of pro-inflammatory cytokines, Dectin-1 and LOX-1 stimulated by A. fumigatus, were also suppressed by pretreatment of α-MSH in RAW264.7 cells. The ratio of P-JNK/T-JNK and P-ERK/T-ERK were down regulated in α-MSH group compared with PBS control group.

CONCLUSION

α-MSH alleviates the severity and decreases fungal load of A. fumigatus keratitis in mice. Migration of neutrophils and macrophages are restrained. α-MSH downregulates the expression of dectin-1 and the ratio of P-JNK/T-JNK and P-ERK/T-ERK in A. fumigatus infection.

The neuroimmune response during stress: A physiological perspective

Stress is an essential adaptive response that enables the organism to cope with challenges and restore homeostasis. Different stressors require distinctive corrective responses in which immune cells play a critical role. Hence, effects of stress on immunity may vary accordingly. Indeed, epidemiologically, stress can induce either inflammation or immune suppression in an organism. However, in the absence of a conceptual framework, these effects appear chaotic, leading to confusion. Here, we examine how stressor diversity is imbedded in the neuroimmune axis. Stressors differ in the brain patterns they induce, diversifying the neuronal and endocrine mediators dispatched to the periphery and generating a wide range of potential immune effects. Uncovering this complexity and diversity of the immune response to different stressors will allow us to understand the involvement of stress in pathological conditions, identify ways to modulate it, and even harness the therapeutic potential embedded in an adaptive response to stress.

Hypoxia Promotes a Mixed Inflammatory-Fibrotic Macrophages Phenotype in Active Sarcoidosis

Background

Macrophages are pivotal cells in sarcoidosis. Monocytes-derived (MD) macrophages have recently been demonstrated to play a major role especially in pulmonary sarcoidosis. From inflammatory tissues to granulomas, they may be exposed to low oxygen tension environments. As hypoxia impact on sarcoidosis immune cells has never been addressed, we designed the present study to investigate MD-macrophages from sarcoidosis patients in this context. We hypothesized that hypoxia may induce functional changes on MD-macrophages which could have a potential impact on the course of sarcoidosis.

Methods

We studied MD-macrophages, from high active sarcoidosis (AS) (n=26), low active or inactive sarcoidosis (IS) (n=24) and healthy controls (n=34) exposed 24 hours to normoxia (21% O₂) or hypoxia (1.5% O₂). Different macrophage functions were explored: hypoxia-inducible factor-1α (HIF-1α) and nuclear factor-kappa B (NF-κB) activation, cytokines secretion, phagocytosis, CD80/CD86/HLA-DR expression, profibrotic response.

Results

We observed that hypoxia, with a significantly more pronounced effect in AS compared with controls and IS, increased the HIF-1α trans-activity, promoted a proinflammatory response (TNFα, IL1ß) without activating NF-κB pathway and a profibrotic response (TGFß1, PDGF-BB) with PAI-1 secretion associated with human lung fibroblast migration inhibition. These results were confirmed by immunodetection of HIF-1α and PAI-1 in granulomas observed in pulmonary biopsies from patients with sarcoidosis. Hypoxia also decreased the expression of CD80/CD86 and HLA-DR on MD-macrophages in the three groups while it did not impair phagocytosis and the expression of CD36 expression on cells in AS and IS at variance with controls.

Conclusions

Hypoxia had a significant impact on MD-macrophages from sarcoidosis patients, with the strongest effect seen in patients with high active disease. Therefore, hypoxia could play a significant role in sarcoidosis pathogenesis by increasing the macrophage proinflammatory response, maintaining phagocytosis and reducing antigen presentation, leading to a deficient T cell response. In addition, hypoxia could favor fibrosis by promoting profibrotic cytokines response and by sequestering fibroblasts in the vicinity of granulomas.

Antimelanogenesis Effects of Theasinensin A

Theasinensin A (TSA) is a major group of catechin dimers mainly found in oolong tea and black tea. This compound is also manufactured with epigallocatechin gallate (EGCG) as a substrate and is refined after the enzyme reaction. In previous studies, TSA has been reported to be effective against inflammation. However, the effect of these substances on skin melanin formation remains unknown. In this study, we unraveled the role of TSA in melanogenesis using mouse melanoma B16F10 cells and normal human epidermal melanocytes (NHEMs) through reverse transcription polymerase chain reaction (RT-PCR), Western blotting analysis, luciferase reporter assay, and enzyme-linked immunosorbent assay analysis. TSA inhibited melanin formation and secretion in α-melanocyte stimulating hormone (α-MSH)-induced B16F10 cells and NHEMs. TSA down-regulated the mRNA expression of tyrosinase (Tyr), tyrosinase-related protein 1 (Tyrp1), and Tyrp2, which are all related to melanin formation in these cells. TSA was able to suppress the activities of certain proteins in the melanocortin 1 receptor (MC1R) signaling pathway associated with melanin synthesis in B16F10 cells: cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB), protein kinase A (PKA), tyrosinase, and microphthalmia-associated transcription factor (MITF). We also confirmed α-MSH-mediated CREB activities through a luciferase reporter assay, and that the quantities of cAMP were reduced by TSA in the enzyme linked immunosorbent assay (ELISA) results. Based on these findings, TSA should be considered an effective inhibitor of hyperpigmentation.

Activity of the growth hormone-releasing hormone antagonist MIA602 and its underlying mechanisms of action in sarcoidosis-like granuloma

OBJECTIVES

Growth hormone-releasing hormone (GHRH) is a potent stimulator of growth hormone (GH) secretion from the pituitary gland. Although GHRH is essential for the growth of immune cells, the regulatory effects of its antagonist in granulomatous disease remain unknown.

METHODS

Here, we report expression of GHRH receptor (R) in human tissue with sarcoidosis granuloma and demonstrate the anti-inflammatory effects of MIA602 (a GHRH antagonist) in two in vitro human granuloma models and an in vivo granuloma model using different methods including ELISA, immunohistochemistry, RNA-seq analysis and flow cytometry.

RESULTS

MIA602 decreases the levels of IL-2, IL-2R, IL-7, IL-12, IL-17A and TNF-α in an in vitro granuloma model. Further, we show that the anti-inflammatory effect of MIA602 appears to be mediated by a reduction in CD45+CD68+ cells in granulomatous tissue and upregulation in PD-1 expression in macrophages. Analysis of the expression of proteins involved in the mitochondrial stage of apoptosis showed that MIA602 increases the levels of caspase-3, BCL-xL/BAK dimer and MCl-1/Bak dimer in the granuloma. These findings indicate that MIA602 may not induce apoptosis.

CONCLUSIONS

Our findings further suggest that GHRH-R is potentially a clinical target for the treatment of granulomatous disease and that MIA602 may be used as a novel therapeutic agent for sarcoidosis.

Experimental models of sarcoidosis: where are we now?

PURPOSE OF REVIEW

Sarcoidosis remains a mysterious disease that presents many challenges both in pathogenetic understanding and in the management of patients. This review presents experimental models for sarcoidosis developed since 2016 and discusses their strengths and weaknesses and how they have contributed to the understanding and therapeutic approaches in this disease. In addition, future directions are proposed to overcome the limitations of current models.

RECENT FINDINGS

New cellular models using infectious antigen as trigger, and transgenic models in mice have recently been developed to study signaling pathways potentially implicated in the pathogenesis of sarcoidosis.

SUMMARY

No model fully reproduces sarcoidosis, but most of them generate data supporting key concepts and some open up therapeutic perspectives, like mTOR inhibition or IL-1β blocking. However, there are still many limitations to these models, largely related to the complexity of sarcoidosis, which might be overcome with new technologies, such as mathematical modeling.

Mammalian Neuropeptides as Modulators of Microbial Infections: Their Dual Role in Defense versus Virulence and Pathogenesis

The regulation of infection and inflammation by a variety of host peptides may represent an evolutionary failsafe in terms of functional degeneracy and it emphasizes the significance of host defense in survival. Neuropeptides have been demonstrated to have similar antimicrobial activities to conventional antimicrobial peptides with broad-spectrum action against a variety of microorganisms. Neuropeptides display indirect anti-infective capacity via enhancement of the host’s innate and adaptive immune defense mechanisms. However, more recently concerns have been raised that some neuropeptides may have the potential to augment microbial virulence. In this review we discuss the dual role of neuropeptides, perceived as a double-edged sword, with antimicrobial activity against bacteria, fungi, and protozoa but also capable of enhancing virulence and pathogenicity. We review the different ways by which neuropeptides modulate crucial stages of microbial pathogenesis such as adhesion, biofilm formation, invasion, intracellular lifestyle, dissemination, etc., including their anti-infective properties but also detrimental effects. Finally, we provide an overview of the efficacy and therapeutic potential of neuropeptides in murine models of infectious diseases and outline the intrinsic host factors as well as factors related to pathogen adaptation that may influence efficacy.

Novel three-dimensional biochip pulmonary sarcoidosis model

Sarcoidosis is a multi-system disorder of granulomatous inflammation which most commonly affects the lungs. Its etiology and pathogenesis are not well defined in part due to the lack of reliable modeling. Here, we present the development of an in vitro three-dimensional lung-on-chip biochip designed to mimic granuloma formation. A lung on chip fluidic macrodevice was developed and added to our previously developed a lung-on-membrane model (LOMM). Granulomas were cultured from blood samples of patients with sarcoidosis and then inserted in the air-lung-interface of the microchip to create a three-dimensional biochip pulmonary sarcoidosis model (3D BSGM). Cytokines were measured after 48 hours. ELISA testing was performed to measure cytokine response difference between LOMM with 3D BSGM. There were statistically significant differences in IL-1ß (P = 0.001953), IL-6 (P = 0.001953), GM-CSF (P = 0.001953), and INF-γ expressions (P = 0.09375) between two groups. The current model represents the first 3D biochip sarcoidosis model created by adding a microfluidics system to a dual-chambered lung on membrane model and introducing developed sarcoid-granuloma to its air-lung-interface.

Antifibrotic and Anti-Inflammatory Actions of α-Melanocytic Hormone: New Roles for an Old Player

The melanocortin system encompasses melanocortin peptides, five receptors, and two endogenous antagonists. Besides pigmentary effects generated by α-Melanocytic Hormone (α-MSH), new physiologic roles in sexual activity, exocrine secretion, energy homeostasis, as well as immunomodulatory actions, exerted by melanocortins, have been described recently. Among the most common and burdensome consequences of chronic inflammation is the development of fibrosis. Depending on the regenerative capacity of the affected tissue and the quality of the inflammatory response, the outcome is not always perfect, with the development of some fibrosis. Despite the heterogeneous etiology and clinical presentations, fibrosis in many pathological states follows the same path of activation or migration of fibroblasts, and the differentiation of fibroblasts to myofibroblasts, which produce collagen and α-SMA in fibrosing tissue. The melanocortin agonists might have favorable effects on the trajectories leading from tissue injury to inflammation, from inflammation to fibrosis, and from fibrosis to organ dysfunction. In this review we briefly summarized the data on structure, receptor signaling, and anti-inflammatory and anti-fibrotic properties of α-MSH and proposed that α-MSH analogues might be promising future therapeutic candidates for inflammatory and fibrotic diseases, regarding their favorable safety profile.

Models Contribution to the Understanding of Sarcoidosis Pathogenesis: "Are There Good Models of Sarcoidosis?"

Sarcoidosis is a systemic, granulomatous, and noninfectious disease of unknown etiology. The clinical heterogeneity of the disease (targeted tissue(s), course of the disease, and therapy response) supports the idea that a multiplicity of trigger antigens may be involved. The pathogenesis of sarcoidosis is not yet completely understood, although in recent years, considerable efforts were put to develop novel experimental research models of sarcoidosis. In particular, sarcoidosis patient cells were used within in vitro 3D models to study their characteristics compared to control patients. Likewise, a series of transgenic mouse models were developed to highlight the role of particular signaling pathways in granuloma formation and persistence. The purpose of this review is to put in perspective the contributions of the most recent models in the understanding of sarcoidosis.