IL-37 expression improves renal function after ischemia and reperfusion in mice model

Renal ischemia is a major problem in the world that lead to renal failure for which no effective treatment is available. Renal ischemia involves a robust inflammatory response, involving up-regulated chemokine expression and leukocyte accumulation, contributes to the mechanism of renal injury and renal failure. IL-37 is a new human cytokine and has an anti-inflammatory function. Currently, it is unknown whether IL-37 suppresses renal inflammatory response to ischemia. We tested the hypothesis that expression of human IL-37 in mouse protects the renal against ischemic injury through suppression of the renal inflammatory response. IL-37 Tg and WT mice were subjected to right renal nephrectomy to induce unilateral model of ischemia the microvascular clamp was positioned around the left renal pedicles. Serum sampling for measurements of TNF-α, IL-1β, Caspase3, MDA, HMGB1, urea and creatinine. Hematoxylin-eosin staining for histological analysis. The resulted data showed that IL-37 has anti-inflammatory effects in renal IRI as evidenced by significant reduction of the inflammatory markers levels TNF-α, IL-1β and HMGB1. IL-37 has potent antioxidant and anti-apoptotic effects with significant reduction in MDA and caspace-3 respectively

IL-37 expression improves renal function after ischemia and reperfusion in mice model

Renal ischemia is a major problem in the world that lead to renal failure for which no effective treatment is available. Renal ischemia involves a robust inflammatory response, involving up-regulated chemokine expression and leukocyte accumulation, contributes to the mechanism of renal injury and renal failure. IL-37 is a new human cytokine and has an anti-inflammatory function. Currently, it is unknown whether IL-37 suppresses renal inflammatory response to ischemia. We tested the hypothesis that expression of human IL-37 in mouse protects the renal against ischemic injury through suppression of the renal inflammatory response. IL-37 Tg and WT mice were subjected to right renal nephrectomy to induce unilateral model of ischemia the microvascular clamp was positioned around the left renal pedicles. Serum sampling for measurements of TNF-α, IL-1β, Caspase3, MDA, HMGB1, urea and creatinine. Hematoxylin-eosin staining for histological analysis. The resulted data showed that IL-37 has anti-inflammatory effects in renal IRI as evidenced by significant reduction of the inflammatory markers levels TNF-α, IL-1β and HMGB1. IL-37 has potent antioxidant and anti-apoptotic effects with significant reduction in MDA and caspace-3 respectively. Keywords: Renal ischemia, IL-37, TNF-α, IL-1β, Caspase-3

IL-37 expression improves renal function after ischemia and reperfusion in mice model

Renal ischemia is a major problem in the world that lead to renal failure for which no effective treatment is available. Renal ischemia involves a robust inflammatory response, involving up-regulated chemokine expression and leukocyte accumulation, contributes to the mechanism of renal injury and renal failure. IL-37 is a new human cytokine and has an anti-inflammatory function. Currently, it is unknown whether IL-37 suppresses renal inflammatory response to ischemia. We tested the hypothesis that expression of human IL-37 in mouse protects the renal against ischemic injury through suppression of the renal inflammatory response. IL-37 Tg and WT mice were subjected to right renal nephrectomy to induce unilateral model of ischemia the microvascular clamp was positioned around the left renal pedicles. Serum sampling for measurements of TNF-α, IL-1β, Caspase3, MDA, HMGB1, urea and creatinine. Hematoxylin-eosin staining for histological analysis. The resulted data showed that IL-37 has anti-inflammatory effects in renal IRI as evidenced by significant reduction of the inflammatory markers levels TNF-α, IL-1β and HMGB1. IL-37 has potent antioxidant and anti-apoptotic effects with significant reduction in MDA and caspace-3 respectively.

Temporal and Quantitative Analysis of Aortic Immunopathologies in Elastase-Induced Mouse Abdominal Aortic Aneurysms

Objective. Elastase-induced abdominal aortic aneurysm (AAA) model is widely used for aneurysmal pathogenesis and translational research. However, temporal alternations in aneurysmal histologies remain unknown. This study is aimed at analyzing temporal immunopathologies of aneurysmal aorta following experimental AAA induction. Methods. Male C57BL/6J mice at the age of 10-14 weeks received intra-aortic infusion of elastase to induce AAAs. Aortic diameters at the baseline and indicated days after AAA induction were measured, and aortae were collected for histopathological analysis. Results. Aorta diameters increased from 0.52 mm at the baseline levels to 0.99 mm, 1.34 mm, and 1.41 mm at days 7, 14, and 28, respectively, corresponding 90%, 158%, and 171% increases over the baseline level. Average aortic diameters did not differ between days 14 and 28. Severe elastin degradation and smooth muscle cell depletion were found at days 14 and 28 as compared to the baseline and day 7. No difference in the scores of medial elastin and SMC destruction was noted between days 14 and 28. Consistent results were found for leukocyte accumulation, neoangiogenesis, and matrix metalloproteinase expression. Twenty-eight days after AAA induction, all aneurysmal pathologies showed an attenuated trend, although most histopathological parameters did no differ between days 14 and 28. Conclusion. Our data suggest that almost aneurysmal immunohistopathologies reach maximal 14 days following AAA induction. Analysis of day 14 histologies is sufficient for AAA pathogenesis and translational studies in elastase-induced mouse experimental AAAs.

cis-Aconitic Acid, a Constituent of Echinodorus grandiflorus Leaves, Inhibits Antigen-Induced Arthritis and Gout in Mice

cis-Aconitic acid is a constituent from the leaves of Echinodorus grandiflorus, a medicinal plant traditionally used in Brazil to treat inflammatory conditions, including arthritic diseases. The present study aimed to investigate the anti-arthritic effect of cis-aconitic acid in murine models of antigen-induced arthritis and monosodium urate-induced gout. The possible underlying mechanisms of action was evaluated in THP-1 macrophages. Oral treatment with cis-aconitic acid (10, 30, and 90 mg/kg) reduced leukocyte accumulation in the joint cavity and C-X-C motif chemokine ligand 1 and IL-1β levels in periarticular tissue. cis-Aconitic acid treatment reduced joint inflammation in tissue sections of antigen-induced arthritis mice and these effects were associated with decreased mechanical hypernociception. Administration of cis-aconitic acid (30 mg/kg p. o.) also reduced leukocyte accumulation in the joint cavity after the injection of monosodium urate crystals. cis-Aconitic acid reduced in vitro the release of TNF-α and phosphorylation of IκBα in lipopolysaccharide-stimulated THP-1 macrophages, suggesting that inhibition of nuclear factor kappa B activation was an underlying mechanism of cis-aconitic acid-induced anti-inflammatory effects. In conclusion, cis-aconitic acid has significant anti-inflammatory effects in antigen-induced arthritis and monosodium urate-induced arthritis in mice, suggesting its potential for the treatment of inflammatory diseases of the joint in humans. Additionally, our findings suggest that this compound may contribute to the anti-inflammatory effect previously reported for E. grandiflorus extracts.

Leukocytospermia induces intraepithelial recruitment of dendritic cells and increases SIV replication in colorectal tissue explants

Mucosal exposure to infected semen accounts for the majority of HIV-1 transmission events, with rectal intercourse being the route with the highest estimated risk of transmission. Yet, the impact of semen inflammation on colorectal HIV-1 transmission has never been addressed. Here we use cynomolgus macaques colorectal tissue explants to explore the effect of leukocytospermia, indicative of male genital tract inflammation, on SIVmac251 infection. We show that leukocytospermic seminal plasma (LSP) has significantly higher concentration of a number of pro-inflammatory molecules compared to normal seminal plasma (NSP). In virus-exposed explants, LSP enhance SIV infection more efficiently than NSP, being the increased viral replication linked to the level of inflammatory and immunomodulatory cytokines. Moreover, LSP induce leukocyte accumulation on the apical side of the colorectal lamina propria and the recruitment of a higher number of intraepithelial dendritic cells than with NSP. These results suggest that the outcome of mucosal HIV-1 infection is influenced by the inflammatory state of the semen donor, and provide further insights into mucosal SIV/HIV-1 pathogenesis.

Alpha-ketoglutarate augments prolyl hydroxylase-2 mediated inactivation of phosphorylated-Akt to inhibit induced-thrombosis and inflammation

Phosphorylation of Akt (pAkt) regulates multiple physiological and pathological processes including thrombosis and inflammation. In an approach to inhibit the pathological signalling of pAkt by prolyl-hydroxylase-2 (PHD2) we employed alpha-ketoglutarate (AKG), a cofactor of PHD2. Octyl-AKG supplementation to platelets promoted PHD2 activity through elevated intracellular AKG:succinate ratio and reduced aggregation in vitro by suppressing pAkt1(Thr308). Augmented PHD2 activity was confirmed by increased hydroxylated-proline alongside enhanced binding of PHD2 to pAkt in AKG-treated platelets. Contrastingly, inhibitors of PHD2 significantly increased pAkt1 in platelets. Octyl-AKG followed similar mechanism in monocytes to inhibit cytokine secretion in vitro. Our data also describe a suppressed pAkt1 and reduced activation of platelet and leukocyte obtained from mice supplemented with dietary-AKG, unaccompanied by alteration in their counts. Dietary-AKG significantly reduced clot formation and leukocyte accumulation in various organs including lung of mice treated with thrombosis-inducing agent carrageenan. Importantly, we observed a significant rescue effect of dietary-AKG on inflamed lung of SARS-CoV-2 infected hamsters. AKG significantly reduced leukocyte accumulation, clot formation and viral load alongside downmodulation of pAkt in lung of the infected animals. Therefore, our study suggests a safe implementation of dietary-AKG in prevention of Akt-driven anomalies including thrombosis and inflammation, highlighting a better pulmonary management in COVID-19.

Inflammatory Cell Recruitment in Cardiovascular Disease

Atherosclerosis, the main underlying pathology for myocardial infarction and stroke, is a chronic inflammatory disease of middle-sized to large arteries that is initiated and maintained by leukocytes infiltrating into the subendothelial space. It is now clear that the accumulation of pro-inflammatory leukocytes drives progression of atherosclerosis, its clinical complications, and directly modulates tissue-healing in the infarcted heart after myocardial infarction. This inflammatory response is orchestrated by multiple soluble mediators that enhance inflammation systemically and locally, as well as by a multitude of partially tissue-specific molecules that regulate homing, adhesion, and transmigration of leukocytes. While numerous experimental studies in the mouse have refined our understanding of leukocyte accumulation from a conceptual perspective, only a few anti-leukocyte therapies have been directly validated in humans. Lack of tissue-tropism of targeted factors required for leukocyte accumulation and unspecific inhibition strategies remain the major challenges to ultimately translate therapies that modulate leukocytes accumulation into clinical practice. Here, we carefully describe receptor and ligand pairs that guide leukocyte accumulation into the atherosclerotic plaque and the infarcted myocardium, and comment on potential future medical therapies.

Vancomycin and daptomycin modulate the innate immune response in a murine model of LPS-induced sepsis

Sepsis is a leading cause of death worldwide, despite the use of multimodal therapies. Common antibiotic regimens are being affected by a rising number of multidrug-resistant pathogens, and new therapeutic approaches are therefore needed. Antibiotics have immunomodulatory properties which appear to be beneficial in the treatment of sepsis. We hypothesized that the last-resort antibiotics vancomycin (VAN) and daptomycin (DMC) modulate cell migration, phagocytosis, and protein cytokine levels in a murine model of lipopolysaccharide (LPS)-induced sepsis. Ten to twelve-week-old C57BL/6 mice ( n = 4–6 animals per group) were stimulated with LPS for 20 h, followed by the administration of VAN or DMC. The outcome parameters were leukocyte accumulation and effector function. Quantification of the immune cells in the peritoneal lavage was performed using flow cytometry analysis. Phagocytosis was measured using pHrodo E. coli BioParticles. The response of the cytokines TNFα, IL-6, and IL-10 was measured in vitro using murine peritoneal macrophages stimulated with LPS and VAN or DMC. VAN decreased both the peritoneal macrophage and the dendritic cell populations following LPS stimulation. DMC reduced the dendritic cell population in the peritoneal cavity in LPS-infected mice. Both antibiotics increased the phagocytic activity in peritoneal macrophages, but this effect was diminished in response to LPS. Phagocytosis of dendritic cells was increased in LPS-infected animals treated with VAN. VAN and DMC differently modulated the levels of pro-and anti-inflammatory cytokines. In a murine model of LPS-induced sepsis, VAN and DMC exhibit immunomodulatory effects on cells involved in innate immunity. The question of whether these antibiotics exhibit synergistic effects in the treatment of septic patients, beyond their bactericidal properties, should be further evaluated in future studies.