scholarly journals A double-edged sword of immuno-microenvironment in cardiac homeostasis and injury repair

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Kang Sun ◽  
Yi-yuan Li ◽  
Jin Jin

AbstractThe response of immune cells in cardiac injury is divided into three continuous phases: inflammation, proliferation and maturation. The kinetics of the inflammatory and proliferation phases directly influence the tissue repair. In cardiac homeostasis, cardiac tissue resident macrophages (cTMs) phagocytose bacteria and apoptotic cells. Meanwhile, NK cells prevent the maturation and transport of inflammatory cells. After cardiac injury, cTMs phagocytose the dead cardiomyocytes (CMs), regulate the proliferation and angiogenesis of cardiac progenitor cells. NK cells prevent the cardiac fibrosis, and promote vascularization and angiogenesis. Type 1 macrophages trigger the cardioprotective responses and promote tissue fibrosis in the early stage. Reversely, type 2 macrophages promote cardiac remodeling and angiogenesis in the late stage. Circulating macrophages and neutrophils firstly lead to chronic inflammation by secreting proinflammatory cytokines, and then release anti-inflammatory cytokines and growth factors, which regulate cardiac remodeling. In this process, dendritic cells (DCs) mediate the regulation of monocyte and macrophage recruitment. Recruited eosinophils and Mast cells (MCs) release some mediators which contribute to coronary vasoconstriction, leukocyte recruitment, formation of new blood vessels, scar formation. In adaptive immunity, effector T cells, especially Th17 cells, lead to the pathogenesis of cardiac fibrosis, including the distal fibrosis and scar formation. CMs protectors, Treg cells, inhibit reduce the inflammatory response, then directly trigger the regeneration of local progenitor cell via IL-10. B cells reduce myocardial injury by preserving cardiac function during the resolution of inflammation.

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Melissa L Martin ◽  
Stephen Dewhurst ◽  
Harris A Gelbard ◽  
Val Goodfellow ◽  
Burns C Blaxall

Heart failure (HF) is a manifestation of most cardiovascular diseases whose increasing prevalence highlights the need for novel therapeutics. The extent of pathologic cardiac remodeling is correlated with clinical outcome. Importantly, cardiac injury enhances cardiac fibroblast (CF) activation, producing myofibroblasts that release pro-fibrotic/inflammatory mediators which target cardiomyocytes (CM), CFs, and local inflammatory cells to exacerbate remodeling. Mixed Lineage Kinases (MLKs) are a family of stress-activated MAPKKKs whose functional role(s) in the heart remain largely unknown. MLK3 has been implicated in HIV-associated neurocognitive disorder (HAND), where it mediates deleterious cross-talk between microglia and neurons, suggesting an analogous mechanism of pathologic intercellular CF-CM communication in HF. We hypothesize that MLK3 exacerbates cardiac remodeling through enhanced CF activation that contributes to pathologic cardiac intercellular communication. We have synthesized a series of MLK3-specific small molecule inhibitors, one of which (URMC-099) was found to attenuate microglial-mediated neurotoxicity in murine models of HAND. To investigate the role of MLK3 in CF activation, neonatal rat ventricular CFs were stimulated with isoproterenol (Iso) or angiotensin II (AngII). Concurrent treatment with URMC-099 attenuated both α-smooth muscle actin expression, indicative of myofibroblast transition, and proinflammatory cytokine production. Further, therapeutic efficacy and specificity of URMC-099 were tested in iso-infused and myocardial infarction (MI) models of HF using wild-type (WT) and MLK3-/- mice (shown to have no overt cardiac phenotype). URMC-099 significantly attenuated cardiac hypertrophy (HW:BW) and reduced interstitial fibrosis (assessed by Masson's Trichrome staining) in an acute iso-pump model of HF in WT mice. Current echocardiographic data post-MI suggest cardioprotection in the MLK3-/- and URMC-099 treated mice. In conclusion, our collaborative data not only suggest a role for MLK3 in cardiac remodeling through pathologic CF activation but indicate a possibly novel paradigm of pathologic intercellular communication in multiple disease states.


2019 ◽  
Vol 2019 ◽  
pp. 1-18
Author(s):  
Kai Chen ◽  
Yiqing Guan ◽  
Yunci Ma ◽  
Dongling Quan ◽  
Jingru Zhang ◽  
...  

Current therapeutic approaches have a limited effect on cardiac remodeling, which is characteristic of cardiac fibrosis and myocardial hypertrophy. In this study, we examined whether Danshenol A (DA), an active ingredient extracted from the traditional Chinese medicine Radix Salviae, can attenuate cardiac remodeling and clarified the underlying mechanisms. Using the spontaneously hypertensive rat (SHR) as a cardiac remodeling model, DA ameliorated blood pressure, cardiac injury, and myocardial collagen volume and improved cardiac function. Bioinformatics analysis revealed that DA might attenuate cardiac remodeling through modulating mitochondrial dysfunction and reactive oxygen species. DA repaired the structure/function of the mitochondria, alleviated oxidative stress in the myocardium, and restored apoptosis of cardiomyocytes induced by angiotensin II. Besides, DA inhibited mitochondrial redox signaling pathways in both the myocardium and cardiomyocytes. Thus, our study suggested that DA attenuates cardiac remodeling induced by hypertension through modulating mitochondrial dysfunction and reactive oxygen species.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Yi Wang ◽  
Zhiheng Guo ◽  
Yongmei Gao ◽  
Ping Liang ◽  
Yanhong Shan ◽  
...  

Abstract Pregnancy-associated cardiomyopathy (PAH) represents a pregnancy-associated myocardial disease that is characterized by the progression of heart failure due to marked left ventricular systolic dysfunction. Compelling evidence has highlighted the potential of angiotensin (Ang) receptor inhibitors as therapeutic targets in PAH treatment. The present study aims to elucidate the molecular mechanisms underlying Ang II receptor inhibitor LCZ696 treatment in PAH. Initially, a PAH mouse model was induced, followed by intraperitoneal injection of LCZ696. Subsequently, cardiomyocytes and fibroblasts were isolated, cultured, and treated with Ang II and LCZ696, followed by detection of the total survival rate, cardiac injury, cardiac fibrosis and apoptosis. Moreover, in order to quantify the cardiac hypertrophy and fibrosis degree of cardiac fibroblasts, the expression levels of markers of cardiac hypertrophy (ANP, βMHC and TIMP2) and markers of fibrosis (collagen I, collagen III and TGF-β) were evaluated. Furthermore, the potential effect of LCZ696 on the extracellular signal-regulated kinase (ERK) signaling pathway was examined. The acquired findings revealed that LCZ696 increased the total survival rate of PAH mice, but decreased cardiac injury, cardiac fibrosis, and apoptosis in vitro. LCZ696 attenuated cardiac injury induced by Ang II through the inhibition the expression of markers of cardiac hypertrophy, fibrosis and apoptosis by inhibiting ERK phosphorylation in vivo and in vitro. Altogether, LCZ676 could potentially alleviate cardiac remodeling in mice with PAH via blockade of the ERK signaling pathway activation. Our findings suggest that LCZ696 could be a potential target for PAH therapy.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Klinsmann Carolo dos Santos ◽  
Sarah Santiloni Cury ◽  
Ana Paula Costa Rodrigues Ferraz ◽  
José Eduardo Corrente ◽  
Bianca Mariani Gonçalves ◽  
...  

Yacon (Smallanthus sonchifolius) is a native Andean plant rich in phenolic compounds, and its effects on dysmetabolism and cardiomyopathy in diabetic rats was evaluated. The rats (10/group) were allocated as follows: C, controls; C + Y, controls treated with Yacon leaf extract (YLE); DM, diabetic controls; and DM + Y, diabetic rats treated with YLE. Type 1 diabetes (T1DM) was induced by the administration of streptozotocin (STZ; 40 mg−1/kg body weight, single dose, i.p.), and treated groups received 100 mg/kg body weight YLE daily via gavage for 30 d. The YLE group shows an improvement in dysmetabolism and cardiomyopathy in the diabetic condition (DM versus DM + Y) promoting a significant reduction of glycemia by 63.39%, an increase in insulin concentration by 49.30%, and a decrease in serum triacylglycerol and fatty acid contents by 0.39- and 0.43-fold, respectively, by ameliorating the pancreatic islet injury, as well as increasing the activity of the antioxidant enzymes (catalase, superoxide dismutase, and glutathione peroxidase) and decreasing the fibrosis and cellular disorganization in cardiac tissue. The apparent benefits of YLE seem to be mediated by ameliorating dysmetabolism and oxidative stress in pancreatic and cardiac tissues.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Himi Tripathi ◽  
Kazuhiro Shindo ◽  
Renee Donahue ◽  
Erhe Gao ◽  
Andrew J Morris ◽  
...  

Introduction and Hypothesis: Acute myocardial infarction (AMI) is the leading cause of morbidity and mortality worldwide. The innate immune response plays a major role in cardiac remodeling after AMI. Lysophosphatidic acid (LPA), produced by autotaxin (ATX) and degraded by Lipid phosphate phosphatase 3 (LPP3), regulates monocytosis and promotes inflammation. However, the role of LPP3 in post-AMI inflammation is not understood. Here, we investigated the possible role of Myeloid-specific Plpp3 KO mice in cardiac and systemic inflammation and resulting in adverse cardiac remodeling post-MI. Methods and Results: To generate mice with Myeloid-specific Plpp3 deletion , female Plpp3 fl/fl mice were crossed to male Plpp3 mice expressing Cre recombinase under the control of the LysM promoter to generate lysm-plpp3. mice. These mice and their littermate control underwent MI or sham surgery. Inflammatory cell content was assessed using flow cytometry and immunohistochemistry. Cardiac function and scar size were assessed by echocardiography and Mason Trichrome staining, respectively. Increased number of Ly6C hi monocytes (CD45 + /Ly6C/G hi /CD115 hi ) and pro-inflammatory macrophages (CD45 + /F4-80 + /CD11b + ) (CD45 + /F4-80 + /CD86 + ), in cardiac tissue of Cre+LysM mice was observed compared to Cre-fl/fl littermate controls during peak post-MI inflammation, as assessed by flow cytometry ( Fig.1A-C ). This increase in inflammatory cells and inflammation may be the consequence of the significant increase in bone marrow and spleen progenitor cell count and proliferation. Moreover, Cre+LysM mice cardiac functional recovery was also reduced significantly ( Fig. 1D-F ) as assessed by echocardiography. Conclusion: Myeloid-specific Plpp3 deletion increases the deleterious effects of inflammation on the ischemic myocardium and ATX/ LPA signaling could represent a novel therapeutic target for future clinical studies of coronary heart diseases.


2017 ◽  
Vol 121 (suppl_1) ◽  
Author(s):  
Ryan M Burke ◽  
Janet K Lighthouse ◽  
Pearl J Quijada ◽  
Ronald Dirkx ◽  
Michael A Trembley ◽  
...  

Pathological cardiac remodeling is initially a compensatory attempt to increase cardiac output, but ultimately leads to the development of fibrosis, a form of scarring that contributes to heart failure (HF). In contrast, physiological cardiac remodeling in response to exercise is not associated with the development of fibrosis and typically remains compensatory. Understanding how cardiac fibroblasts (CF), the primary source of extracellular matrix in the heart, respond to pathological and physiological cues might lead to novel approaches to limit the maladaptive effects of pathological cardiac remodeling. We performed RNA sequencing to define genes that are differentially regulated in CF during physiological (swimming) or pathological (pressure overload) remodeling. This study revealed that cardiac expression of the s mall pr oline r ich 2b ( Sprr2b) gene is restricted to CFs and is significantly elevated in disease and lost in exercise. We demonstrate that SPRR2B drives CF proliferation, but not myofibroblast differentiation, in response to pathological cues. SPRR2B facilitates an interaction between MDM2 and USP7, a nuclear deubiquitinase that leads to proteasomal degradation of p53. SPRR2B-USP7-MDM2 complex formation and p53 degradation is at least partially dependent upon phosphorylation of SPRR2B by Src-family NRTKs. SPRR2B thus relieves p53-mediated constraints on cell cycle progression in response to Src-dependent signaling, leading to CF accumulation. Importantly, SPRR2B expression is elevated in cardiac tissue from human HF patients relative to individuals without heart disease and positively correlates with a proliferative, activated gene expression profile in HF patient CF. Treatment of human HF fibroblasts with IGF-1/H 2 O 2 to mimic physiological cues significantly abrogated SPRR2B expression and increased expression of p53-dependent cell cycle checkpoint genes, which correlated with a less activated phenotype. Taken together, this study defines a unique tissue-specific role of Sprr2b in driving pathological CF cell cycle progression that may underlie the development of cardiac fibrosis.


2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Fanmuyi Yang ◽  
Anping Dong ◽  
Susan Smyth

Bone marrow derived cells, especially inflammatory cells, may contribute to the pathological progression of pressure overload induced left ventricular (LV) hypertrophy and cardiac fibrosis. Previously, we reported that inflammatory cell accumulation and upregulation of cytokines in hearts of mice that had undergone transverse aortic constriction (TAC) surgery predicted later cardiac hypertrophic and fibrotic remodeling. However, the underlining mechanisms are still not clear. One potential mechanism for inflammatory cells to modulate their environment and affect surrounding cells is through release of cargo stored in granules. Jinx mice - which contain a single point mutation in Unc13d encoding the Munc13-4 protein, a limiting factor in vesicular priming and fusion - have defects in granular secretion in hematopoietic cells, such as platelets, NK cells, and neutrophils. In the current study, we investigated the role of bone marrow cell granule secretion in TAC-induced LV remodeling by creating with bone marrow transplantation chimeric mice specifically lacking Munc13-4 in marrow derived cells. Both wild-type mice (WT) that were transplanted with WT bone marrow and WT mice that received Jinx bone marrow developed LVH and a classic fetal reprogramming response early (7 days) after TAC. However, at later times (5 weeks), mice lacking Munc13-4 in bone marrow-derived cells failed to sustain the cardiac hypertrophy observed in mice with WT bone marrow. No difference in cardiac fibrosis was observed at early or late times. These results suggest that sustained LVH in the setting of pressure overload depends on factor(s) secreted from bone marrow-derived cells, likely from either platelets, NK cells and/or neutrophils. Inhibiting granule cargo release may represent a novel therapeutic target to prevent the development of LVH.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A609-A609
Author(s):  
Sevasti Karaliota ◽  
Dimitris Stellas ◽  
Vasiliki Stravokefalou ◽  
Bethany Nagy ◽  
Cristina Bergamaschi ◽  
...  

BackgroundIL-15 is a cytokine which stimulates the proliferation and cytotoxic function of CD8+ T and NK cells. We have produced and applied the native heterodimeric IL-15 (hetIL-15) on several preclinical models, which have supported the anti-tumor activity of hetIL-15. Based on these results, hetIL-15 has advanced to clinical trials. The objectives of this study were to explore how hetIL-15 shapes the tumor microenviroment and to characterize the interactions between tumor-infiltrating lymphoid and myeloid cells.MethodsWe studied the efficacy of locoregional administration of heterodimeric IL-15 (hetIL-15) in two different orthotopic triple-negative breast cancer (TNBC) mouse models, syngeneic for C57BL/6 and Balb/c, respectively. The effects of hetIL-15 on immune cells were analyzed by flow cytometry, immunohistochemistry (IHC) and gene expression profiling. The profile of the novel infiltrated dendritic cell populations was further explored by bulk and single cell RNAseq.Results hetIL-15 resulted in tumor eradication in 40% of treated mice and reduction of metastasis. Subsequent rechallenges with the same cell line failed to generate tumor regrowth, suggesting the development of immunological memory in hetIL-15 treated mice. hetIL-15 promoted tumor accumulation of proliferating and cytotoxic CD8+ T and NK cells. Additionally, peritumoral hetIL-15 administration resulted in an increased tumor infiltration of both conventional type 1 dendritic cells (cDC1s) and of a novel DC population found only in the hetIL-15 treated animals. Phenotypic profile analysis confirmed the expression of several cDC1 specific markers, including CD103 and IRF8 on this DC population.Transcriptomics and flow analysis of intratumoral dendritic cells indicate that the new hetIL-15 induced cells reside preferentially in the tumors and are distinct from cDC1 and cDC2 populations. Both cDC1s and the novel DC population were inversely correlated with the tumor size.ConclusionsLocoregional administration of hetIL-15 results in complete eradication of EO771 and significant reduction of 4T1 primary breast cancer tumors, prolonged survival and long-lasting specific anti-tumor immunity. hetIL-15 increases the tumor infiltration of activated T and NK cells and intensifies the tumor infiltration of conventional type 1 dendritic cells (cDC1) and a new population of dendritic cells. We propose that the anti-cancer activity of hetIL-15 in primary EO771 tumors is orchestrated by the interplay of NK, CD8+T cells, cDC1 and a novel subset of DCs with a distinct phenotypic profile. These findings suggest a role for hetIL-15 in the treatment of breast cancer.Ethics ApprovalThe study was approved by the National Cancer Institute-Frederick Animal Care and Use Committee, approval number 19–324 and was conducted in accordance with the ACUC guidelines and the NIH Guide for the Care and Use of Laboratory Animals.


Immuno ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 174-193
Author(s):  
Jenny Valentina Garmendia ◽  
Juan Bautista De Sanctis

NK cells are lymphocytes involved in the innate and adaptative immune response. These cells are located in peripheral blood and tissues with ample functions, from immune vigilant to tolerogenic reactions. In the endometrium, NK cell populations vary depending on age, hormones, and inflammation. When pregnancy occurs, tissue-resident NK cells and conventional NK cells are recruited to protect the fetus, a tolerogenic response. On the contrary, in the inflamed endometrium, various inflammatory cells down-regulate NK tolerance and impair embryo implantation. Therefore, NK cells’ pharmacological modulation is difficult to achieve. Several strategies have been used, from progesterone, lipid emulsions to steroids; the success has not been as expected. However, new therapeutic approaches have been proposed to decrease the endometrial inflammatory burden and increase pregnancy success based on understanding NK cell physiology.


2021 ◽  
Vol 22 (2) ◽  
pp. 751
Author(s):  
Min Young Park ◽  
Bala Murali Krishna Vasamsetti ◽  
Wan Seop Kim ◽  
Hee Jung Kang ◽  
Do-Young Kim ◽  
...  

Porcine heart xenotransplantation is a potential treatment for patients with end-stage heart failure. To understand molecular mechanisms of graft rejection after heart transplantation, we transplanted a 31-day-old alpha-1,3-galactosyltransferase knockout (GTKO) porcine heart to a five-year-old cynomolgus monkey. Histological and transcriptome analyses were conducted on xenografted cardiac tissue at rejection (nine days after transplantation). The recipient monkey’s blood parameters were analyzed on days −7, −3, 1, 4, and 7. Validation was conducted by quantitative real-time PCR (qPCR) with selected genes. A non-transplanted GTKO porcine heart from an age-matched litter was used as a control. The recipient monkey showed systemic inflammatory responses, and the rejected cardiac graft indicated myocardial infarction and cardiac fibrosis. The transplanted heart exhibited a total of 3748 differentially expressed genes compared to the non-transplanted heart transcriptome, with 2443 upregulated and 1305 downregulated genes. Key biological pathways involved at the terminal stage of graft rejection were cardiomyopathies, extracellular interactions, and ion channel activities. The results of qPCR evaluation were in agreement with the transcriptome data. Transcriptome analysis of porcine cardiac tissue at graft rejection reveals dysregulation of the key molecules and signaling pathways, which play relevant roles on structural and functional integrities of the heart.


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