Abstract 13402: FHL-1 Contributes to and Colocalizes With Titin in Cardiac Hypertrophy

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Nesrine El-Bizri ◽  
Jing Liu ◽  
Rachel Matt ◽  
Rugmani P Iyer ◽  
Girija Raman ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cardiac Hypertrophy ◽  
Diastolic Dysfunction ◽  
Neonatal Rat ◽  
In Vivo Studies ◽  
Myoblast Differentiation ◽  
Mrna Levels ◽  
Tissue Samples ◽  
Diastolic Compliance

Increased myocardial stiffness is a hallmark of impaired diastole in heart failure (HF). Hypo-phosphorylation of the N2B unique sequence (N2Bus) of titin (TTN), a giant myofilament protein, increases passive tension leading to diastolic dysfunction in HF. Enhancing the altered N2Bus phosphorylation improves cardiac stiffness and function. FHL-1, an interacting protein potentially modulating N2Bus phosphorylation is increased in HF. FHL-1 knockout mice display blunted cardiac hypertrophy and improved diastolic compliance in response to pressure-overload by transverse aortic constriction, TAC. FHL-1 also regulates skeletal muscle hypertrophy. We hypothesize that FHL-1 contributes to cardiac hypertrophy and colocalizes/interacts with TTN in heart failure. In house IHC data showed site-specific N2Bus hypo-phosphorylation at S4099, S4010 and S4185 in human HCM and/or DCM tissue samples. Longitudinal in-vivo studies showed that FHL-1 and cardiac hypertrophy markers genes were increased in left ventricles (LV) of TAC mice using RNA-seq. A persistently enhanced FHL-1 protein expression by immunoblotting and mass spectrometry strongly correlated with LV hypertrophy at 1, 4, and 6 weeks post-TAC. In addition, LV hypertrophy correlated negatively with function (fractional shortening). Increases in FHL-1 and hypertrophy markers mRNA levels were confirmed by RT-qPCR in neonatal rat ventricular myocytes (NRVM) under phenylephrine (PE) and endothelin-1 (ET-1) induced hypertrophy. Under similar conditions, FHL-1 protein levels were increased by immunofluorescence (IF) in cytoplasmic, perinuclear and nuclear regions of NRVM. Colocalization of phospho-TTN and FHL-1 was observed in NRVM and was enhanced under PE- and ET-1 induced hypertrophy. IF studies in human skeletal myotubes showed that FHL-1 expression was increased during myoblast differentiation and IGF1-E3R induced hypertrophy. Preliminary data using Microscale Thermophoresis showed binding affinity between N2Bus and FHL-1 proteins. Our studies show that FHL-1 contributes to hypertrophy in addition to N2B hypo-phosphorylation status contributing to diastolic dysfunction in HF. Targeting FHL-1 and TTN can be a potential strategy to improve diastolic compliance in HF.

Myofibroblast Deficiency of LSD1 Alleviates TAC-Induced Heart Failure

2021 ◽  
Author(s):  
Jin-Ling Huo ◽  
Lemin Jiao ◽  
Qi An ◽  
Xiuying Chen ◽  
Yuruo Qi ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cardiac Hypertrophy ◽  
Cardiac Remodeling ◽  
Transforming Growth Factor ◽  
Heart Function ◽  
Wild Type Mouse ◽  
Neonatal Rat ◽  
Mouse Heart ◽  
Ang Ii

Rationale: Histone lysine specific demethylase 1 (LSD1) is an important epigenetic anti-tumor drug target, whose inhibitors are currently in phase Ⅰ/Ⅱ clinical trials. However, the potential side effects of LSD1 inhibition in the progress of cardiac remodeling to heart failure remain to be investigated. Objective: To evaluate the roles of myofibroblast- or cardiomyocyte-specific LSD1 deficiency in pressure overload-induced cardiac remodeling. Methods and Results: Adult mouse cardiac fibroblasts (CFs)，neonatal rat cardiac myocytes (NRCMs) and fibroblasts (NRCFs) were isolated, respectively. The myofibroblast-specific and cardiomyocyte-specific LSD1 inducible knockout mice were then generated. We found that LSD1 was increased not only in human DCM (dilated cardiomyopathy) hearts, but also in wild type mouse heart homogenates and isolated CFs, following 20 weeks of transverse aortic constriction (TAC). The upregulation of LSD1 was also observed in Ang II-treated NRCFs, which was reversed by LSD1 silence or its activity inhibition by ORY-1001. These findings suggested a potential involvement of LSD1 in cardiac remodeling. Importantly, myofibroblast-specific LSD1 inducible knockout in vivo significantly alleviated systolic dysfunction, cardiac hypertrophy and fibrosis, following 6 and 20 weeks of TAC. Mechanistically, through RNA-sequencing and the following western blot analysis, we found that loss of LSD1 in Ang II-induced myofibroblasts not only inhibited the intracellular upregulation of transforming growth factor β1 (TGFβ1), its downstream effectors Smad2/3 phosphorylation, as well as the phosphorylation of p38, ERK1/2 and JNK, but also reduced the supernatant TGFβ1 secretion, which then decreased myocyte hypertrophy in the indirect co-culture model. On the other hand, cardiomyocyte-specific LSD1 inducible knockout in vivo triggered the reprogramming of fetal genes, mild cardiac hypertrophy and dysfunction under both basal and stressed conditions. Conclusions: Our findings, for the first time, implicate that myofibroblast-specific LSD1 deletion attenuates TAC-induced cardiac remodeling and improves heart function, suggesting that LSD1 is a potential therapeutic target for late stage heart failure.

scholarly journals LCZ696 Ameliorates Oxidative Stress and Pressure Overload-Induced Pathological Cardiac Remodeling by Regulating the Sirt3/MnSOD Pathway

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Shi Peng ◽  
Xiao-feng Lu ◽  
Yi-ding Qi ◽  
Jing Li ◽  
Juan Xu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Heart Failure ◽  
Cardiac Hypertrophy ◽  
Pressure Overload ◽  
Neonatal Rat ◽  
Cardiomyocyte Hypertrophy ◽  
Rat Cardiomyocytes ◽  
Pathological Cardiac Hypertrophy

Aims. We aimed to investigate whether LCZ696 protects against pathological cardiac hypertrophy by regulating the Sirt3/MnSOD pathway. Methods. In vivo, we established a transverse aortic constriction animal model to establish pressure overload-induced heart failure. Subsequently, the mice were given LCZ696 by oral gavage for 4 weeks. After that, the mice underwent transthoracic echocardiography before they were sacrificed. In vitro, we introduced phenylephrine to prime neonatal rat cardiomyocytes and small-interfering RNA to knock down Sirt3 expression. Results. Pathological hypertrophic stimuli caused cardiac hypertrophy and fibrosis and reduced the expression levels of Sirt3 and MnSOD. LCZ696 alleviated the accumulation of oxidative reactive oxygen species (ROS) and cardiomyocyte apoptosis. Furthermore, Sirt3 deficiency abolished the protective effect of LCZ696 on cardiomyocyte hypertrophy, indicating that LCZ696 induced the upregulation of MnSOD and phosphorylation of AMPK through a Sirt3-dependent pathway. Conclusions. LCZ696 may mitigate myocardium oxidative stress and apoptosis in pressure overload-induced heart failure by regulating the Sirt3/MnSOD pathway.

Nanocurcumin: A Double-Edged Sword for Microcancers

2020 ◽  
Vol 26 (45) ◽  
pp. 5783-5792
Author(s):  
Kholood Abid Janjua ◽  
Adeeb Shehzad ◽  
Raheem Shahzad ◽  
Salman Ul Islam ◽  
Mazhar Ul Islam
Keyword(s):  
Intracellular Signaling ◽  
Dosage Forms ◽  
The Body ◽  
In Vivo Studies ◽  
Mrna Levels ◽  
Anticancer Activities ◽  
Road Map ◽  
Anticancer Effects

There is compelling evidence that drug molecules isolated from natural sources are hindered by low systemic bioavailability, poor absorption, and rapid elimination from the human body. Novel approaches are urgently needed that could enhance the retention time as well as the efficacy of natural products in the body. Among the various adopted approaches to meet this ever-increasing demand, nanoformulations show the most fascinating way of improving the bioavailability of dietary phytochemicals through modifying their pharmacokinetics and pharmacodynamics. Curcumin, a yellowish pigment isolated from dried ground rhizomes of turmeric, exhibits tremendous pharmacological effects, including anticancer activities. Several in vitro and in vivo studies have shown that curcumin mediates anticancer effects through the modulation (upregulation and/or downregulations) of several intracellular signaling pathways both at protein and mRNA levels. Scientists have introduced multiple modern techniques and novel dosage forms for enhancing the delivery, bioavailability, and efficacy of curcumin in the treatment of various malignancies. These novel dosage forms include nanoparticles, liposomes, micelles, phospholipids, and curcumin-encapsulated polymer nanoparticles. Nanocurcumin has shown improved anticancer effects compared to conventional curcumin formulations. This review discusses the underlying molecular mechanism of various nanoformulations of curcumin for the treatment of different cancers. We hope that this study will make a road map for preclinical and clinical investigations of cancer and recommend nano curcumin as a drug of choice for cancer therapy.

scholarly journals Qiliqiangxin Attenuates Phenylephrine-Induced Cardiac Hypertrophy through Downregulation of MiR-199a-5p

2016 ◽  
Vol 38 (5) ◽  
pp. 1743-1751 ◽  
Author(s):  
Haifeng Zhang ◽  
Shanshan Li ◽  
Qiulian Zhou ◽  
Qi Sun ◽  
Shutong Shen ◽  
...  
Keyword(s):  
Cell Surface ◽  
Cardiac Hypertrophy ◽  
Natriuretic Peptide ◽  
Neonatal Rat ◽  
Immunofluorescent Staining ◽  
Mouse Heart ◽  
Mrna Levels ◽  
Elevated Protein ◽  
Ischemic Stress

Background/Aims: Qiliqiangxin (QL), a traditional Chinese medicine, has long been used to treat chronic heart failure. Previous studies demonstrated that QL could prevent cardiac remodeling and hypertrophy in response to hypertensive or ischemic stress. However, little is known about whether QL could modulate cardiac hypertrophy in vitro, and (if so) whether it is through modulation of specific hypertrophy-related microRNA. Methods: The primary neonatal rat ventricular cardiomyocytes were isolated, cultured, and treated with phenylephrine (PE, 50 µmol/L, 48 h) to induce hypertrophy in vitro, in the presence or absence of pretreatment with QL (0.5 µg/ml, 48 h). The cell surface area was determined by immunofluorescent staining for α-actinin. The mRNA levels of hypertrophic markers including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and β-myosin heavy chain (MYH7) were assayed by qRT-PCRs. The protein synthesis of cardiomyocytes was determined by the protein/DNA ratio. The miR-199a-5p expression level was quantified in PE-treated cardiomyocytes and heart samples from acute myocardial infarction (AMI) mouse model. MiR-199a-5p overexpression was used to determine its role in the anti-hypertrophic effect of QL on cardiomyocytes. Results: PE induced obvious enlargement of cell surface in cardiomyocytes, paralleling with increased ANP, BNP, and MYH7 mRNA levels and elevated protein/DNA ratio. All these changes were reversed by the treatment with QL. Meanwhile, miR-199a-5p was increased in AMI mouse heart tissues. Of note, the increase of miR-199a-5p in PE-treated cardiomyocytes was reversed by the treatment with QL. Moreover, overexpression of miR-199a-5p abolished the anti-hypertrophic effect of QL on cardiomyocytes. Conclusion: QL prevents PE-induced cardiac hypertrophy. MiR-199a-5p is increased in cardiac hypertrophy, while reduced by treatment with QL. miR-199a-5p suppression is essential for the anti-hypertrophic effect of QL on cardiomyocytes.

Abstract P279: YAP, a Transcriptional Cofactor of the Hippo Pathway, Regulates Cardiomyocyte Growth, Survival, and Proliferation

2011 ◽  
Vol 109 (suppl_1) ◽  
Author(s):  
Yanfei Yang ◽  
Noritsugu Nakano ◽  
Junichi Sadoshima
Keyword(s):  
Cardiac Hypertrophy ◽  
Hippo Pathway ◽  
Neonatal Rat ◽  
Border Zone ◽  
Luciferase Reporter ◽  
Tunel Staining ◽  
H2o2 Treatment ◽  
Rat Hearts ◽  
The Hippo Pathway

Mst1 and Lats2, components of the mammalian Hippo pathway, stimulate apoptosis and inhibit hypertrophy of cardiomyocytes (CMs), thereby mediating reperfusion injury and heart failure. YAP, a transcription factor co-factor, is negatively regulated by the Hippo pathway, and controls cell survival, proliferation and tissue regeneration. The role of YAP in regulating growth and death of CMs is poorly understood. YAP overexpression in CMs induced cardiac hypertrophy, as indicated by increases in cell size (+1.2 fold, p<0.01), protein content (+1.1 fold, p<0.01) and ANF (luciferase reporter activity +1.7 fold, mRNA +2.2 fold, and staining +2.7 fold, p<0.01). Lats2 phosphorylates YAP at Serine 127, which induces cytoplasmic translocation of YAP, whereas YAP(S127A) is localized constitutively in the nucleus. Expression of YAP(S127A) enhanced hypertrophy in cultured CMs compared to that of wild type YAP (+1.87 fold ANF staining, p<0.05), suggesting that the Mst1/Hippo pathway negatively regulates cardiac hypertrophy through YAP. YAP inhibited cell death induced by H2O2 treatment, as evaluated with TUNEL staining (-65%, p<0.05) and CellTiter Blue assays (+34.9%, p<0.01), indicating that YAP plays an essential role in mediating CM survival. Interestingly, YAP also significantly increased Ki67 positive cells in cultured CMs compared to LacZ (+2.65 fold, p<0.05). We used a mouse model of chronic myocardial infarction (MI) to evaluate the function of YAP in the heart in vivo. Although YAP is diffusely localized both in the nucleus and cytosol in CMs in control hearts, CMs in the border zone of MI exhibited nuclear localization of YAP whereas YAP was excluded from the nucleus in CMs in the remodeling area four days after MI (+6.52 fold and +1.28 fold). Some of the YAP positive CMs in the border zone exhibited positive co-staining with Ki67, suggesting that YAP potentially induces CM proliferation. A significant increase in nuclear YAP and Ki67 positive CMs (+2.95 fold, p<0.01 and +2.18 fold, p<0.05) was also observed in neonatal rat hearts whose apex was surgically resected three days before euthanasia. These results suggest that YAP plays an important role in mediating not only hypertrophy and survival, but also proliferation of CMs in response to myocardial injury.

Abstract 214: MicroRNA-451 Aggravates Lipotoxic Cardiomyopathy Through Suppression of the LKB1/AMPK Signaling Pathway

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Yasuhide Kuwabara ◽  
Takahiro Horie ◽  
Osamu Baba ◽  
Toru Kita ◽  
Takeshi Kimura ◽  
...  
Keyword(s):  
Cardiac Hypertrophy ◽  
Diabetic Cardiomyopathy ◽  
Calcium Binding ◽  
Saturated Fatty Acids ◽  
Mammalian Target Of Rapamycin ◽  
Neonatal Rat ◽  
Albumin Concentration ◽  
Dependent Manner ◽  
Ceramide Level

Rationale: In some type 2 diabetes mellitus (T2D) patients without hypertension, cardiac hypertrophy and attenuated cardiac function are observed, and this insult is termed “diabetic cardiomyopathy.” Tons of evidence suggests that microRNAs are involved in cardiac diseases. However, the functions of microRNAs in the diabetic cardiomyopathy induced by T2D and obesity are not fully understood. Methods and Results: C57BL/6 mice were fed a high-fat diet (HFD) for 20 weeks, which induced obesity and T2D. MicroRNA microarray and real-time PCR revealed that miR-451 levels were significantly increased in the T2D mouse hearts (n=4-5, p<0.05). Because excess supply of saturated fatty acids is a cause of diabetic cardiomyopathy, we stimulated neonatal rat cardiac myocytes (NRCMs) with palmitate in physiological albumin concentration and confirmed that miR-451 expression was increased in a dose-dependent manner (n=6-12, p<0.01). Loss of miR-451 function ameliorated palmitate-induced lipotoxicity in NRCMs (n=4, p<0.05). Calcium-binding protein 39 (Cab39) is a scaffold protein of liver kinase B1 (LKB1), an upstream kinase of AMP-activated protein kinase (AMPK). Cab39 was a direct target of miR-451 in NRCMs and Cab39 overexpression rescued the palmitate-induced lipotoxicity in NRCMs (n=4, p<0.01). To clarify miR-451 functions in vivo, we generated cardiomyocyte-specific miR-451 knockout (cKO) mice. HFD-induced cardiac hypertrophy and contractile reserves were ameliorated in cKO mice compared with HFD-fed control mice. Protein levels of Cab39 and phosphorylated AMPK were increased and phosphorylated mammalian target of rapamycin (mTOR) was reduced in HFD-fed cKO mouse hearts compared with HFD-fed control mouse hearts (n=10-12, p<0.05). We also measured the lipotoxic intermediates, triglyceride and ceramide, in these mouse hearts using HPLC-evaporative light scattering detector (ELSD). Although there was no difference in triglyceride levels (n=3-5), ceramide level was decreased in HFD-fed cKO mice compared with HFD-fed control mice (n=3-5, p<0.05). Conclusions: Our results indicate that miR-451 exacerbates diabetic cardiomyopathy. miR-451 is a potential therapeutic target for cardiac disease caused by T2D and obesity.

Abstract P320: The Gut Microbial Metabolite Butyrate Suppresses Cardiac Hypertrophy Via An Epigenetic Mechanism

2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Masahiko Umei ◽  
Hiroshi Akazawa ◽  
Akiko Saga-Kamo ◽  
Hiroki Yagi ◽  
Qing Liu ◽  
...  
Keyword(s):  
Heart Failure ◽  
Fatty Acid ◽  
Cardiac Hypertrophy ◽  
Short Chain Fatty Acid ◽  
Chain Fatty Acid ◽  
Epigenetic Mechanism ◽  
Neonatal Rat ◽  
Short Chain ◽  
Rat Cardiomyocytes ◽  
Hypertrophic Growth

Introduction: Short-chain fatty acids (SCFA) are one of the gut microbial metabolites that can influence host health and disease. We previously reported that gut dysbiosis is associated with heart failure, and that the proportion of butyrate-producing bacteria is decreased in the gut of patients with heart failure. Purpose: We investigated the molecular mechanism of butyrate in the development of cardiac hypertrophy. Methods and Results: Single-cell transcriptome analysis and co-expression network analysis revealed that G protein-coupled receptors for short-chain fatty acid receptors were not expressed in cardiomyocytes and that Olfr78 was expressed in vascular smooth muscle cells in the heart. On the other hand, treatment with butyrate inhibited ET1-induced and isoproterenol (ISO)-induced hypertrophic growth in cultured neonatal rat cardiomyocytes. Moreover, butyrate increased the acetylation levels of histone H3, suggesting the inhibitory effect of butyrate on HDAC. In addition, butyrate caused the degradation of HDAC2 and up-regulation of Inpp5f, encoding inositol polyphosphate-5-phosphatase f, leading to a significant decrease in the phosphorylation levels of Akt and glycogen synthase kinase 3β (GSK3β). Finally, intraperitoneal injection of butyrate inhibited ISO-induced cardiac hypertrophy in mice. These results suggest that butyrate protects against hypertrophic responses via suppression of the Akt-GSK3β pathway through HDAC inhibition. Conclusion: In the heart, there were no known short-chain fatty acid receptors in cardiomyocytes. However, butyrate was shown to have an epigenetic mechanism in suppressing effect on cardiomyocyte hypertrophy via suppression of HDAC2-Akt-GSK3β axis. Our results uncover a potential link between dysbiosis of intestinal microbiota and the development of cardiac hypertrophy.

Abstract 2423: B-type Natriuretic Peptide Upregulates Erythropoietin Receptor Gene Expression via Protein Kinase G in Heart Failure

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Yoshiaki Ohyama ◽  
Toru Tanaka ◽  
Takehisa Shimizu ◽  
Hiroshi Doi ◽  
Norimichi Koitabashi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Heart Failure ◽  
Protein Kinase ◽  
Cardiac Myocytes ◽  
Natriuretic Peptide ◽  
Neonatal Rat ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Failing Heart ◽  
Epor Expression

Backgroud: Recent studies demonstrated non-hematopoietical effects of Erythropoietin (Epo) and its receptor (EpoR) in a variety of tissues including cardiovascular system. Epo treatment improves cardiac function in patients with heart failure and reduces infarct size after ischemia/reperfusion injury in the heart. However, little attention has been paid for the endogenous regulatory mechanisms regulating EpoR expression. In this study, we hypothesize that B-type natriuretic peptide upregulates EpoR gene expression in failing heart. Methods and Results: Wister rats underwent transverse aortic constriction surgery to induce hypertrophy. RT-PCR analyses of those rats showed that EpoR mRNA levels were increased in the left ventricle and positively correlated with the levels of BNP mRNA (n=10, r=0.67, p<0.05). Next we examined the expression of EpoR in human failing heart by using autopsy specimens and found that EpoR mRNA levels were significantly elevated in patients with dilated cardiomyopathy compared with those in normal heart. Immunohistochemistry of endomyocardial biopsy specimens of failing heart (n=54) showed that EpoR mRNA levels were correlated with severity of cardiac dysfunction estimated by diameter of cardiac chambers, pathomorphology, serum BNP concentration and functional class of New York Heart Association. Interestingly, stimulation of cultured neonatal rat cardiac myocytes with BNP, but not with hypertrophic reagents including endothelin I, angiotensin II and norepinephrine, significantly increased the EpoR mRNA levels in a time-dependent manner. Overexpression of cGMP-dependent protein kinase (PKG) increased EpoR transcript in cultured cardiac myocytes. BNP-induced EpoR expression was abrogated in the presence of KT5823, a specific inhibitor for PKG. Conclusion: These results suggest a role for BNP in mediating an induction of EpoR expression in failing myocardium and indicate that the cardiac EpoR gene is a target of cGMP/PKG signaling.

Abstract 285: Cardiac Inflammation and Fibrosis Induced by Heart Failure Are Reversed by Short-Duration Estrogen Therapy

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Andrea Iorga ◽  
Rangarajan Nadadur ◽  
Salil Sharma ◽  
Jingyuan Li ◽  
Mansoureh Eghbali
Keyword(s):  
Heart Failure ◽  
Estrogen Therapy ◽  
Pressure Overload ◽  
Decompensated Heart Failure ◽  
Left Ventricular ◽  
Neonatal Rat ◽  
In Vivo Model ◽  
Anti Inflammatory

Heart failure is generally characterized by increased fibrosis and inflammation, which leads to functional and contractile defects. We have previously shown that short-term estrogen (E2) treatment can rescue pressure overload-induced decompensated heart failure (HF) in mice. Here, we investigate the anti-inflammatory and anti-fibrotic effects of E2 on reversing the adverse remodeling of the left ventricle which occurs during the progression to heart failure. Trans-aortic constriction procedure was used to induce HF. Once the ejection fraction reached ∼30%, one group of mice was sacrificed and the other group was treated with E2 (30 αg/kg/day) for 10 days. In vitro, co-cultured neonatal rat ventricular myocytes and fibroblasts were treated with Angiotensin II (AngII) to simulate cardiac stress, both in the presence or absence of E2. In vivo RT-PCR showed that the transcript levels of the pro-fibrotic markers Collagen I, TGFβ, Fibrosin 1 (FBRS) and Lysil Oxidase (LOX) were significantly upregulated in HF (from 1.00±0.16 to 1.83±0.11 for Collagen 1, 1±0.86 to 4.33±0.59 for TGFβ, 1±0.52 to 3.61±0.22 for FBRS and 1.00±0.33 to 2.88±0.32 for LOX) and were reduced with E2 treatment to levels similar to CTRL. E2 also restored in vitro AngII-induced upregulation of LOX, TGFβ and Collagen 1 (LOX:1±0.23 in CTRL, 6.87±0.26 in AngII and 2.80±1.5 in AngII+E2; TGFβ: 1±0.08 in CTRL, 3.30±0.25 in AngII and 1.59±0.21 in AngII+E2; Collagen 1: 1±0.05 in CTRL.2±0.01 in AngII and 0.65±0.02 (p<0.05, values normalized to CTRL)). Furthermore, the pro-inflammatory interleukins IL-1β and IL-6 were upregulated from 1±0.19 to 1.90±0.09 and 1±0.30 to 5.29±0.77 in the in vivo model of HF, respectively, and reversed to CTRL levels with E2 therapy. In vitro, IL-1β was also significantly increased ∼ 4 fold from 1±0.63 in CTRL to 3.86±0.14 with AngII treatment and restored to 1.29±0.77 with Ang+E2 treatment. Lastly, the anti-inflammatory interleukin IL-10 was downregulated from 1.00±0.17 to 0.49±0.03 in HF and reversed to 0.67±0.09 in vivo with E2 therapy (all values normalized to CTRL). This data strongly suggests that one of the mechanisms for the beneficial action of estrogen on left ventricular heart failure is through reversal of inflammation and fibrosis.

Limitations of studying keloid scars using the nude athymic mouse model

2002 ◽  
Vol 10 (2) ◽  
pp. 56-61 ◽  
Author(s):  
Mp Hillmer ◽  
S Salama ◽  
Sm Macleod
Keyword(s):  
Mouse Model ◽  
Scar Tissue ◽  
In Vivo Studies ◽  
Athymic Mice ◽  
Athymic Mouse ◽  
Tissue Samples ◽  
Keloid Scars ◽  
Central Calcification ◽  
Sample Identity

Keloid scars are benign fibroproliferative growths that respond poorly to treatment. This study sought to determine the efficacy of three different glucocorticoids (triamcinolone, methylprednisolone and dexamethasone) in altering human keloid scar tissue implanted in athymic mice. Keloid tissue obtained from three patients (one man and two women) who sought cosmetic removal of their scars was implanted into athymic mice for a duration of 15 or 30 days. The keloid tissue was examined histopathologically and evaluated by a dermatopathologist who was blinded to sample identity and who was using predetermined qualitative scoring criteria. The appearance of central calcification, granulation tissue, foreign body granulomatous reaction and acute inflammatory reaction complicated the comparison of the keloid tissue samples. However, on the basis of observations reported in the present paper, it appears that triamcinolone should remain the treatment of choice for keloid scars. The athymic mouse model that is used for studying keloid scars is the best available approach to in vivo studies; however, limitations identified in this study confound the interpretation of experimental data. Ideally, promising and novel therapies should be investigated clinically.

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