Day-night dependence of gene expression and inflammatory responses in the remodeling murine heart post-myocardial infarction

2016 ◽  
Vol 311 (6) ◽  
pp. R1243-R1254 ◽  
Author(s):  
Michael Bennardo ◽  
Faisal Alibhai ◽  
Elena Tsimakouridze ◽  
Nirmala Chinnappareddy ◽  
Peter Podobed ◽  
...  

Diurnal or circadian rhythms are fundamentally important for healthy cardiovascular physiology and play a role in timing of onset and tolerance to myocardial infarction (MI) in patients. Whether time of day of MI triggers different molecular and cellular responses that can influence myocardial remodeling is not known. This study was designed to test whether time of day of MI triggers different gene expression, humoral, and innate inflammatory responses that contribute to cardiac repair after MI. Mice were infarcted by left anterior descending coronary artery ligation (MI model) within a 2-h time window either shortly after lights on or lights off, and the early remodeling responses at 8 h postinfarction were examined. We found that sleep-MI preferentially triggers early expression of genes associated with inflammatory responses, whereas wake-MI triggers more genes associated with metabolic pathways and transcription/translation, by microarray analyses. Homozygous clock mutant mice exhibit altered diurnal gene expression profiles, consistent with their cycling before onset of MI. In the first 8 h, crucial for innate immune responses to MI, there are also significant differences in sleep-MI and wake-MI serum cytokine responses and in neutrophil infiltration to infarcted myocardium. By 1-wk post-MI, there are differences in survivorship between the sleep and wake MI mice that could be explained by the different molecular and cellular responses. Our whole body physiology, tissues, and cells exhibit endogenous daily rhythms, and understanding their role in triggering effective responses after MI could lead to new strategies to benefit patients with cardiovascular disease.

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Tatsuro Kitahara ◽  
Yasuchika Takeishi ◽  
Tetsuro Shishido ◽  
Satoshi Suzuki ◽  
Shigehiko Kato ◽  
...  

High-mobility group box 1 (HMGB1) is a nuclear DNA-binding protein and is released from necrotic cells, inducing inflammatory responses and promoting tissue repair and angiogenesis. To test the hypothesis that HMGB1 enhances angiogenesis and restores cardiac dysfunction after myocardial infarction, we generated transgenic mouse with cardiac specific overexpression of HMGB1 (HMGB1-Tg) using α-myosin heavy chain (MHC) promoter. The left anterior descending coronary artery was ligated in HMGB1-Tg and wild-type littermate (Wt) mice. After coronary artery ligation, HMGB1 was released into circulation from the necrotic cardiomyocytes of HMGB1 overexpressing hearts. The size of myocardial infarction was smaller in HMGB1-Tg than in Wt mice (figure ). Echocardiography and cardiac catheterization demonstrated that cardiac remodeling and dysfunction after myocardial infarction were prevented in HMGB1-Tg mice compared to Wt mice. Furthermore, survival rate after myocardial infarction in HMGB1-Tg mice was higher than that in Wt mice (figure ). Immunohistochemical staining revealed that capillary and arteriole formations after myocardial infarction were enhanced in HMGB1-Tg mice. We demonstrated the first in vivo evidence that HMGB1 enhances angiogenesis, restores cardiac dysfunction, and improves survival after myocardial infarction. These results may provide a novel therapeutic approach for left ventricular dysfunction after myocardial infarction.


2020 ◽  
Vol 127 (Suppl_1) ◽  
Author(s):  
Yong Sook Kim ◽  
Hyang Hee Cho ◽  
Ju Hee Jun ◽  
Dong Im Cho ◽  
Meeyoung Cho ◽  
...  

Background: Inhibitor of NF-κB kinase (IKK), an upstream of nuclear factor-kappa B (NF-κB), is a critical modulator for pathophysiological inflammation. IKKε is a non-classical IKK and has been studied in infectious diseases and cancers. However, the role of IKKε in a myocardial infarction (MI) has not been addressed. Methods and Results: In this study, we used IKKε knockout (KO) mice to induce MI by coronary artery ligation. The IKKε KO group showed poor early survival rate, large cardiac fibrosis (14.7±4.8% in KO vs. 31.1±10.2% in WT, p <0.05), and low fractional shortening (13.47±1.21% in KO vs. 16.36±4.46% in WT, p <0.05) compared with WT group. Next, we investigated the inflammatory responses and found that inflammatory markers such as inducible nitric oxide synthase (iNOS) and CD80 were much higher in both cardiac macrophages and bone marrow-derived macrophages (BMDM) in the IKKε KO group than in the wild type (WT) group. To explore the responsible mediator, we performed phosphorylated protein array and found phosphorylated p38 was significantly downregulated in the IKKε knockout BMDM. Conversely, both knockdown of p38 by siRNA and inhibition of p38 by SB203580 treatment in RAW264.7 cells upregulated iNOS. More interestingly, IKKε deficient cardiac fibroblasts showed highly accumulated nuclear p53 and exhibited immature differentiation. The levels of myofibroblast markers containing α-smooth muscle actin, periostin, and transforming growth factor-β1 were lower, and functional contractility was substantially impaired in the cardiac fibroblasts isolated from IKKε KO mice. Conclusion: Our data showed excessive inflammation was associated with p38 inactivation in macrophages and pathological fibrosis was resulted from immature myofibroblast phenotype with p53 upregulation. Collectively, IKKε is involved in the control of inflammation resolution and wound healing process in the infarcted myocardium.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
T Borchert ◽  
A Hess ◽  
M Lukacevic ◽  
T L Ross ◽  
F M Bengel ◽  
...  

Abstract Background/Introduction Myocardial infarction (MI) triggers local inflammation to support endogenous healing and repair. Recent imaging studies of the macrophage- and microglia-expressed mitochondrial translocator protein (TSPO) identified concurrent neuroinflammation after acute MI and in chronic heart failure. The source of this neuroinflammation and its relationship to cardiac function early and late after MI are unknown. Purpose We aimed to characterize the cellular basis of the TSPO PET signal by modulating early inflammation via clodronate-mediated macrophage depletion, and modifying late mitochondrial function using the TSPO inhibitor PK11195. Methods C57BL/6 mice underwent permanent coronary artery ligation (n=47) or sham surgery (n=9). Subgroups were treated 24h prior surgery with clodronate liposomes (n=18) to deplete peripheral macrophages or continuously with the cardioprotective TSPO inhibitor PK11195 (n=13). Cardiac and neuroinflammation were evaluated by whole-body PET using the TSPO ligand 18F-GE180 at 1wk, 4wk and 8wk after surgery. Cardiac function and perfusion were assessed by ECG-gated 99mTc-sestamibi SPECT. Results Untreated MI mice showed elevated TSPO signal in the infarct territory compared to sham at 1wk post-MI (ID/g, 10.5±2.9 vs 7.2±1.6, p<0.001), and elevated remote myocardial TSPO signal at 8wk (ID/g, 9±1.9 vs 7±1.6, p=0.003). TSPO signal in brain of MI mice was also increased compared to sham at 1wk (ID/g, 2.1±0.3 vs 1.8±0.2, p=0.006) and 8wk (ID/g, 2.0±0.3 vs 1.8±0.2, p=0.033), reflecting neuroinflammation. Clodronate macrophage depletion lowered the infarct territory TSPO signal at 1wk compared to untreated (ID/g, 4.9±1 vs 10.5±3, p<0.001), consistent with lack of peripheral macrophage recruitment. Conversely, brain TSPO remained elevated (ID/g, 2.7±0.3 vs 2.2±0.3, p<0.001), suggesting resident microglial activation as the source of cerebral PET signal. Late signal at 8wk was comparable between clodronate and untreated (p=NS). TSPO inhibition by PK11195 treatment did not affect acute TSPO signal in heart or brain compared to untreated (p=NS). At 8wk, remote myocardial signal was reduced (ID/g, 7.4±1 vs 9.0±2, p=0.040) in parallel with attenuated cardiac dysfunction in PK11195 treated mice (%EF, 49.8±6 vs 37.3±5, p<0.001). Late brain TSPO signal at 8wk was comparable between PK11195 treatment and untreated (p=NS). Consistently, cardiac and brain TSPO signal were proportional (r=0.637, p<0.001), and neuroinflammation was correlated to cardiac function at 8wk after MI (r=−0.345, p=0.005). Conclusions Cardiac TSPO signal reflects acute macrophage activity and chronic mitochondrial dysfunction in heart failure. Neuroinflammation derives from resident microglia, and is proportional to cardiac function at late stages. As such, TSPO PET provides insight into inflammation and mitochondrial dysfunction in progressive heart failure, and may guide novel therapies such as cardioprotection via TSPO inhibition.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jeffrey L. Ebersole ◽  
Radhakrishnan Nagarajan ◽  
Sreenatha Kirakodu ◽  
Octavio A. Gonzalez

AbstractWe used a nonhuman primate model of ligature-induced periodontitis to identify patterns of gingival transcriptomic after changes demarcating phases of periodontitis lesions (initiation, progression, resolution). A total of 18 adult Macaca mulatta (12–22 years) had ligatures placed (premolar, 1st molar teeth) in all 4 quadrants. Gingival tissue samples were obtained (baseline, 2 weeks, 1 and 3 months during periodontitis and at 5 months resolution). Gene expression was analyzed by microarray [Rhesus Gene 1.0 ST Array (Affymetrix)]. Compared to baseline, a large array of genes were significantly altered at initiation (n = 6049), early progression (n = 4893), and late progression (n = 5078) of disease, with the preponderance being up-regulated. Additionally, 1918 genes were altered in expression with disease resolution, skewed towards down-regulation. Assessment of the genes demonstrated specific profiles of epithelial, bone/connective tissue, apoptosis/autophagy, metabolism, regulatory, immune, and inflammatory responses that were related to health, stages of disease, and tissues with resolved lesions. Unique transcriptomic profiles occured during the kinetics of the periodontitis lesion exacerbation and remission. We delineated phase specific gene expression profiles of the disease lesion. Detection of these gene products in gingival crevicular fluid samples from human disease may contribute to a better understanding of the biological dynamics of the disease to improve patient management.


1989 ◽  
Vol 66 (2) ◽  
pp. 712-719 ◽  
Author(s):  
T. I. Musch ◽  
R. L. Moore ◽  
P. G. Smaldone ◽  
M. Riedy ◽  
R. Zelis

The hemodynamic response to maximal exercise was determined in sedentary and trained rats with a chronic myocardial infarction (MI) produced by coronary artery ligation and in rats that underwent sham operations (SHAM). Infarct size in the MI groups of rats comprised 28–29% of the total left ventricle and resulted in both metabolic and hemodynamic changes that suggested that these animals had moderate compensated heart failure. The training regimen used in the present study produced significant increases in maximal O2 uptake (VO2max) when expressed in absolute terms (ml/min) or when normalized for body weight (ml.min-1.kg-1) and consisted of treadmill running at work loads that were equivalent to 70–80% of the animal's VO2max for a period of 60 min/day, 5 days/wk over an 8- to 10-wk interval. This training paradigm produced two major cardiocirculatory adaptations in the MI rat that had not been elicited previously when using a training paradigm of a lower intensity. First, the decrement in the maximal heart rate response to exercise (known as “chronotropic incompetence”) found in the sedentary MI rat was completely reversed by endurance training. Second, the downregulation of cardiac myosin isozyme composition from the fast ATPase V1 isoform toward the slower ATPase (V2 and V3) isoforms in the MI rat was partially reversed by endurance training. These cardiac adaptations occurred without a significant increase in left ventricular pump function as an increase in maximal cardiac output (Qmax) and maximal stroke volume (SVmax) did not occur in the trained MI rat.(ABSTRACT TRUNCATED AT 250 WORDS)


2003 ◽  
Vol 26 (4) ◽  
pp. 351-357 ◽  
Author(s):  
W.G. Kim ◽  
Y.C. Shin ◽  
S.W. Hwang ◽  
C. Lee ◽  
C.Y. Na

We report a comparison of the effects of myocardial infarction in dogs and sheep using sequential ligation of the left anterior descending artery (LAD) and its diagonal branch (DA), with hemodynamic, ultrasonographic and pathological evaluations. Five animals were used in each group. After surgical preparation, the LAD was ligated at a point approximately 40% of the distance from the apex to the base of the heart, and after one hour, the DA was ligated at the same level. Hemodynamic and ultrasonographic measurements were performed preligation, 30 minutes after LAD ligation, and 1 hour after DA ligation. As a control, two animals in each group were used for the simultaneous ligation of the LAD and the DA. Two months after the coronary ligation, the animals were evaluated as previously, and killed for postmortem examination of their hearts. All seven animals in the dog group survived the experimental procedures, while in the sheep group only animals with sequential ligation of the LAD and DA survived. Statistically significant decreases in systemic arterial blood pressure and cardiac output, and an increase in the pulmonary artery capillary wedge pressure (PACWP) were observed one hour after sequential ligation of the LAD and its DA in the sheep, while only systemic arterial pressures decreased in the dog. Ultrasonographic analyses demonstrated variable degrees of anteroseptal dyskinesia and akinesia in all sheep, but in no dogs. Data two months after coronary artery ligation showed significant increases in central venous pressure, pulmonary artery pressure, and PACWP in the sheep, but not in the dog. Left ventricular end-diastolic dimension and left ventricular end-systolic dimension in ultrasonographic studies were also increased only in the sheep. Pathologically, the well-demarcated thin-walled transmural anteroseptal infarcts with chamber enlargement were clearly seen in all specimens of sheep, and only-mild-to-moderate chamber enlargements with endocardial fibrosis were observed in the dog hearts. In conclusion, this study confirms that the dog is not a suitable model for myocardial infarction with failure by coronary artery ligation despite negligent operative mortality, when compared directly with an ovine model.


2021 ◽  
Author(s):  
Li Guoquan ◽  
Du Junwei ◽  
He Qi ◽  
Fu Xinghao ◽  
Ji Feihong ◽  
...  

Abstract BackgroundHashimoto's thyroiditis (HT), also known as chronic lymphocytic thyroiditis, is a common autoimmune disease, which mainly occurs in women. The early manifestation was hyperthyroidism, however, hypothyroidism may occur if HT was not controlled for a long time. Numerous studies have shown that multiple factors, including genetic, environmental, and autoimmune factors, were involved in the pathogenesis of the disease, but the exact mechanisms were not yet clear. The aim of this study was to identify differentially expressed genes (DEGs) by comprehensive analysis and to provide specific insights into HT. MethodsTwo gene expression profiles (GSE6339, GSE138198) about HT were downloaded from the Gene Expression Omnibus (GEO) database. The DEGs were assessed between the HT and normal groups using the GEO2R. The DEGs were then sent to the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. The hub genes were discovered using Cytoscape and CytoHubba. Finally, NetworkAnalyst was utilized to create the hub genes' targeted microRNAs (miRNAs). ResultsA total of 62 DEGs were discovered, including 60 up-regulated and 2 down-regulated DEGs. The signaling pathways were mainly engaged in cytokine interaction and cytotoxicity, and the DEGs were mostly enriched in immunological and inflammatory responses. IL2RA, CXCL9, IL10RA, CCL3, CCL4, CCL2, STAT1, CD4, CSF1R, and ITGAX were chosen as hub genes based on the results of the protein-protein interaction (PPI) network and CytoHubba. Five miRNAs, including mir-24-3p, mir-223-3p, mir-155-5p, mir-34a-5p, mir-26b-5p, and mir-6499-3p, were suggested as likely important miRNAs in HT. ConclusionsThese hub genes, pathways and miRNAs contribute to a better understanding of the pathophysiology of HT and offer potential treatment options for HT.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Vasundhara Kain ◽  
Kevin A Ingle ◽  
Janusz Kabarowski ◽  
Sumanth D Prabhu ◽  
Ganesh V Halade

12/15 lipoxygenase (LOX) is crucial in the inflammatory process leading to diabetes and atherosclerosis. However, the role of 12/15 LOX in myocardial infarction (MI) and left ventricle (LV) remodeling is unclear. We assessed the role of 12/15 LOX in resolving inflammation in post-MI LV remodeling. 8-12 weeks old C57BL/6J wild-type (WT; n=67) and 12/15 LOX (LOX –/– ; n=78) male mice were subjected to permanent coronary artery ligation surgery and monitored through day (d)1 and d5. No MI surgery mice were maintained as d0 naïve controls. LOX -/- mice showed higher survival rate, improved fractional shortening with reduced remodeling and edema index than WT at d1 and d5 post-MI (all p<0.05). LOX -/- mice showed increased Cxcl5 expression at d1 post-MI, consistent with stimulated neutrophil recruitment in the infarct region that was decreased at d5 compared to WT. LOX -/- mice infarct had increased expression of Ccl2 and Cxcl1, that stimulated an earlier recruitment of monocytes with increased macrophages population at d5 (all p<0.05) compared to WT. The altered kinetics of immune cells post-MI indicates a rapid resolving phase, through increase in alternative macrophage phenotypes with reduced collagen density in LOX -/- mice compared to WT mice at d5 post-MI. LOX -/- mice showed a coordinated COX-1 and COX-2 response at d1 post MI, leading to an evident increase in 5-LOX and hemoxygenase-1 (HO-1) at d5 post-MI. 12/15 LOX deletion enhanced the recruitment of alternative macrophages with secretion of HO-1 to resolve inflammation. In-vitro addition of LOX metabolite 12 hydroxyeicosatetraenoic acid to LOX -/- fibroblast induced early expression of COX-2 and 5-LOX compared to WT, indicating 5LOX role in resolution of inflammation. Post-MI increased expression of TIMP-1 and decrease in MMP-9 at d1 and α-SMA at d5 in LOX -/- mice suggested controlled differentiation of fibroblast-to-myofibroblast which is key event during ventricular tissue repair and resolving phase. This change is supported by increased expression of tgf-βi, ctgf and admats-2 (all P<0.05) at d5 post MI. In conclusion, absence of 12/15 LOX improves post-MI survival rates and attenuates LV dysfunction by resolving inflammation through coordination of 5-LOX and HO-1 as key inflammation resolving enzymes.


2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Raffay S Khan ◽  
Jay C Sy ◽  
Milton Brown ◽  
Mario D Martinez ◽  
Niren Murthy ◽  
...  

During acute myocardial infarction (MI) there is excessive necrosis of myocardial cells, leading to the release of large amounts of DNA, representing a potential target for drug delivery. Hoechst, a commonly used molecule for staining nuclei, binds to the minor groove of double-stranded DNA and can be functionalized to contain reactive groups such as free amines, sulfhydryls, and biotin moieties. Insulin-like growth factor-1 (IGF-1), a small molecule with a short half-life is protective immediately following MI, though there is potential for long-term toxicity and off-target effects. Therefore, we hypothesized that conjugating IGF-1 to Hoechst would increase targeting of IGF-1 to the injured myocardium. Hoechst-IGF1 (H-IGF1) was synthesized by binding Hoechst-biotin to biotinylated IGF-1 via a fluorescent streptavidin linker. Intact cells did not show nuclear staining with H-IGF1, while permeabilized cells had a significant increase in blue fluorescent Hoechst staining, indicating H-IGF1 was cell impermeable but could still bind DNA. Activity of H-IGF1 was demonstrated by Akt phosphorylation in cultured cardiac progenitor cells and was similar to native IGF-1. To determine in-vivo targeting of H-IGF1 to MI, mice underwent 30 minutes of coronary artery ligation followed by reperfusion (I/R). Six hours following MI, mice were injected intravenously with 70ng of H-IGF1, S-IGF1 (streptavidin bound IGF-1 only) or PBS followed by in vivo imaging at 30 and 120 minutes post-injection. At 30 minutes post-injection, we found 3.2% (2.2 of 70ng) of the injected dose of H-IGF1 in infarcted hearts compared with 1.8% (1.3 of 70ng) of S-IGF1 (n=5-7; p<0.05). To confirm that targeting of H-IGF1 was dependent on binding DNA, H-IGF1 pre-bound to double-stranded DNA was injected intravenously after I/R. This led to a significant (p<0.05) decrease in targeted IGF-1 levels. IGF-1 levels determined by ELISA 2 hours post-injection demonstrated a similar trend with increased targeting of H-IGF1 compared with S-IGF1 treated mice (4.2±0.6 ng vs. 2.4±0.2 ng; p<0.05). In conclusion, our data demonstrate that intravenous delivery of Hoechst-conjugated IGF-1 increases myocardial targeting. This provides a novel strategy for delivery of growth factors for the treatment of MI.


Sign in / Sign up

Export Citation Format

Share Document