P5996HDAC inhibition improves myofibrillar relaxation and metabolism in a feline model of HFpEF

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Wallner ◽  
D Eaton ◽  
R Berretta ◽  
J Wu ◽  
M Jeong ◽  
...  
Keyword(s):  
Mitochondrial Function ◽  
Ex Vivo ◽  
Pressure Overload ◽  
Left Ventricular ◽  
Metabolic Reprogramming ◽  
Mrna Levels ◽  
Hdac Inhibition ◽  
Feline Model ◽  
Alveolar Capillary

Abstract Background Heart failure (HF) with preserved ejection fraction (HFpEF) accounts for about 50% of all cases of HF and there are currently no effective therapies. Purpose To assess the effects of histone deacetylase (HDAC) inhibition on cardiac and mitochondrial function and the plasma metabolome in a large mammalian model of slow-progressive pressure overload with features of HFpEF. Methods Male domestic short hair cats (n=26, aged 2mo), underwent either sham (S) procedures (n=5) or aortic constriction with a customized pre-shaped band (n=21), resulting in slow progressive pressure overload during growth. 2 months post-banding, animals were treated daily with either 10mg/kg suberoylanilide hydroxamic acid (b+SAHA) (n=8), a pan-HDAC inhibitor, or vehicle (b+veh) (n=8) for 2 months. Serial in-vivo cardiopulmonary phenotyping was performed monthly, and invasive hemodynamic and gas exchange parameters were evaluated 4 months post-banding. Ex-vivo myofibril mechanical studies and blood-based metabolomic profiling were performed. Data is presented as mean±SEM. Results Echocardiography at 4-months post-banding revealed that b+SAHA animals had a significant reduction in left ventricular hypertrophy (LVH) and LA size vs. b+veh animals. Left ventricular end-diastolic pressure (LVEDP) and mean pulmonary arterial pressure (mPAP) were significantly lower in b+SAHA vs. b+veh. SAHA treatment also improved ex-vivo myofibril relaxation independent of LVH and this effect correlated with in-vivo improvements of LV relaxation. Furthermore, SAHA treatment preserved lung structure, and improved lung compliance and oxygenation, reflected by a decrease in alveolar-capillary wall thickness and intrapulmonary shunt. SAHA treatment also reduced perivascular fluid cuffs around extra-alveolar vessels, suggesting attenuated alveolar-capillary stress failure. Treatment with SAHA caused an increase in both oxygen consumption in-vivo and the percentage of type 1 skeletal muscle fibers (higher oxidative capacity). SAHA also increased mRNA levels of coactivators that regulate mitochondrial function and induced metabolic reprogramming towards mitochondrial oxidation preferentially utilizing fatty acids. SAHA treated HeLa cells showed a significant increase in oxidative phosphorylation and ATP production. Effects of SAHA Conclusion These results show that slow-progressive pressure overload mimics critical features of HFpEF. SAHA can improve cardiac, pulmonary, and metabolic derangements caused by chronic pressure overload. Therefore, HDAC inhibition may be an interesting therapeutic strategy to treat the ever growing HFpEF population. Acknowledgement/Funding NIH [HL33921 to S.R.H, HL116848, HL127240 to T.A.M]; AHA [16SFRN31400013 to T.A.M.]; Medical University of Graz [M.W.], Stadt Graz [M.W.]

scholarly journals HDAC inhibition improves cardiopulmonary function in a feline model of diastolic dysfunction

2020 ◽  
Vol 12 (525) ◽  
pp. eaay7205 ◽  
Author(s):  
Markus Wallner ◽  
Deborah M. Eaton ◽  
Remus M. Berretta ◽  
Laura Liesinger ◽  
Matthias Schittmayer ◽  
...  
Keyword(s):  
Diastolic Dysfunction ◽  
Diastolic Pressure ◽  
Ex Vivo ◽  
Pressure Overload ◽  
Left Ventricular ◽  
Blood Oxygenation ◽  
Hdac Inhibition ◽  
Major Health Problem ◽  
Feline Model

Heart failure with preserved ejection fraction (HFpEF) is a major health problem without effective therapies. This study assessed the effects of histone deacetylase (HDAC) inhibition on cardiopulmonary structure, function, and metabolism in a large mammalian model of pressure overload recapitulating features of diastolic dysfunction common to human HFpEF. Male domestic short-hair felines (n = 31, aged 2 months) underwent a sham procedure (n = 10) or loose aortic banding (n = 21), resulting in slow-progressive pressure overload. Two months after banding, animals were treated daily with suberoylanilide hydroxamic acid (b + SAHA, 10 mg/kg, n = 8), a Food and Drug Administration–approved pan-HDAC inhibitor, or vehicle (b + veh, n = 8) for 2 months. Echocardiography at 4 months after banding revealed that b + SAHA animals had significantly reduced left ventricular hypertrophy (LVH) (P < 0.0001) and left atrium size (P < 0.0001) versus b + veh animals. Left ventricular (LV) end-diastolic pressure and mean pulmonary arterial pressure were significantly reduced in b + SAHA (P < 0.01) versus b + veh. SAHA increased myofibril relaxation ex vivo, which correlated with in vivo improvements of LV relaxation. Furthermore, SAHA treatment preserved lung structure, compliance, blood oxygenation, and reduced perivascular fluid cuffs around extra-alveolar vessels, suggesting attenuated alveolar capillary stress failure. Acetylation proteomics revealed that SAHA altered lysine acetylation of mitochondrial metabolic enzymes. These results suggest that acetylation defects in hypertrophic stress can be reversed by HDAC inhibitors, with implications for improving cardiac structure and function in patients.

Translational mechanisms accelerate the rate of protein synthesis during canine pressure-overload hypertrophy

1999 ◽  
Vol 277 (6) ◽  
pp. H2176-H2184 ◽  
Author(s):  
Yoshitatsu Nagatomo ◽  
Blase A. Carabello ◽  
Masayoshi Hamawaki ◽  
Shintaro Nemoto ◽  
Takeshi Matsuo ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Balloon Catheter ◽  
Pressure Overload ◽  
Left Ventricular ◽  
Ascending Aorta ◽  
Translational Efficiency ◽  
Mrna Levels ◽  
Hypertrophic Growth ◽  
Translational Mechanisms

This study examined how translational mechanisms regulate the rate of cardiac protein synthesis during canine pressure overload in vivo. Acute aortic stenosis (AS) was produced by inflating a balloon catheter in the ascending aorta for 6 h; sustained AS was created by controlled banding of the ascending aorta. AS caused significant hypertrophy as reflected by increased left ventricular (LV) mass after 5 and 10 days. To monitor LV protein synthesis in vivo, myosin heavy chain (MHC) synthesis was measured by continuous infusion of radiolabeled leucine. Acute AS accelerated the rate of myosin synthesis without a corresponding increase in ribosomal RNA, indicating an increase in translational efficiency. Total MHC synthesis (mg MHC/LV per day) was significantly increased at 5 and 10 days of sustained AS. Total MHC degradation was not significantly altered at 5 days of AS but increased at 10 days of AS in concordance with a new steady state with respect to growth. Translational capacity (mg total RNA/LV) was significantly increased after 5 and 10 days of AS and was preceded by an increase in the rate of ribosome formation. MHC mRNA levels remained unchanged during AS. These findings demonstrate that cardiac protein synthesis is accelerated in response to pressure overload by an initial increase in translational efficiency, followed by an adaptive increase in translational capacity during sustained hypertrophic growth.

Paired PV Loop Analysis and Biaxial Mechanical Testing Characterize Differences in Left Ventricular Tissue Stiffness of Volume Overload and Angiotensin-Induced Pressure Overload Hearts

2021 ◽  
Author(s):  
Rachel Childers ◽  
Aaron Trask ◽  
Jun Liu ◽  
Pamela Lucchesi ◽  
Keith Gooch
Keyword(s):  
Mechanical Properties ◽  
Ex Vivo ◽  
Pressure Overload ◽  
Volume Overload ◽  
Left Ventricular ◽  
Cell Phenotype ◽  
Biaxial Testing ◽  
Loop Analysis ◽  
Tissue Mass

Abstract Pressure overload (PO) and volume overload (VO) of the heart result in distinctive changes to geometry, due to compensatory structural remodeling. This remodeling potentially leads to changes in tissue mechanical properties. Understanding such changes is important, as tissue modulus has an impact on cardiac performance, disease progression, and influences on cell phenotype. Pressure-Volume (PV) loop analysis, a clinically-relevant method for measuring left ventricular (LV) chamber stiffness, was performed in vivo on control rat hearts and rats subjected to either chronic PO (4-weeks) or VO (8-weeks). Immediately following PV loops, biaxial testing was performed on LV free wall tissue to directly measure tissue mechanical properties. The ß coefficient, an index of chamber stiffness calculated from the PV loop analysis, increased 98% in PO (n=4) and decreased 38% in VO (n=5) compared to control (n=6). Material constants of LV walls obtained from ex vivo biaxial testing (n =10), were not changed in PO, and decreased by about half in VO compared to control. PV loop analysis showed the expected increase in chamber stiffness of PO and expected decrease in chamber stiffness of VO. Biaxial testing showed a decreased modulus of the myocardium of the VO model, but no changes in the PO model, this suggests the increased chamber stiffness in PO, as shown in the PV loop analysis, may be secondary to changes in tissue mass and/or geometry but not an increase in passive tissue mechanical properties.

scholarly journals MK2‐Deficient Mice Are Bradycardic and Display Delayed Hypertrophic Remodeling in Response to a Chronic Increase in Afterload

2021 ◽  
Vol 10 (4) ◽  
Author(s):  
Matthieu Ruiz ◽  
Maya Khairallah ◽  
Dharmendra Dingar ◽  
George Vaniotis ◽  
Ramzi J. Khairallah ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Mitochondrial Permeability Transition ◽  
Ex Vivo ◽  
Systolic Function ◽  
Pressure Overload ◽  
Left Ventricular ◽  
Mitogen Activated Protein Kinase ◽  
Mrna Levels ◽  
Cardiac Phenotype ◽  
Deficient Mice

Background Mitogen‐activated protein kinase–activated protein kinase‐2 (MK2) is a protein serine/threonine kinase activated by p38α/β. Herein, we examine the cardiac phenotype of pan MK2‐null (MK2 −/− ) mice. Methods and Results Survival curves for male MK2 +/+ and MK2 −/− mice did not differ (Mantel‐Cox test, P =0.580). At 12 weeks of age, MK2 −/− mice exhibited normal systolic function along with signs of possible early diastolic dysfunction; however, aging was not associated with an abnormal reduction in diastolic function. Both R‐R interval and P‐R segment durations were prolonged in MK2‐deficient mice. However, heart rates normalized when isolated hearts were perfused ex vivo in working mode. Ca 2+ transients evoked by field stimulation or caffeine were similar in ventricular myocytes from MK2 +/+ and MK2 −/− mice. MK2 −/− mice had lower body temperature and an age‐dependent reduction in body weight. mRNA levels of key metabolic genes, including Ppargc1a , Acadm , Lipe , and Ucp3, were increased in hearts from MK2 −/− mice. For equivalent respiration rates, mitochondria from MK2 −/− hearts showed a significant decrease in Ca 2+ sensitivity to mitochondrial permeability transition pore opening. Eight weeks of pressure overload increased left ventricular mass in MK2 +/+ and MK2 −/− mice; however, after 2 weeks the increase was significant in MK2 +/+ but not MK2 −/− mice. Finally, the pressure overload–induced decrease in systolic function was attenuated in MK2 −/− mice 2 weeks, but not 8 weeks, after constriction of the transverse aorta. Conclusions Collectively, these results implicate MK2 in (1) autonomic regulation of heart rate, (2) cardiac mitochondrial function, and (3) the early stages of myocardial remodeling in response to chronic pressure overload.

Abstract 462: Cardiac-specific LMCD1/dyxin-knockout in Mice Blunts Pressure Overload-induced Activation of Calcineurin Signaling

2020 ◽  
Vol 127 (Suppl_1) ◽  
Author(s):  
Lucia S Kilian ◽  
Jakob Voran ◽  
Nesrin Schmiedel ◽  
Katharina Stiebeling ◽  
Julika Richter ◽  
...  
Keyword(s):  
Protein Level ◽  
Heart Function ◽  
Pressure Overload ◽  
Protective Role ◽  
Left Ventricular ◽  
Cardiomyocyte Hypertrophy ◽  
Mrna Levels

We and others have shown that LMCD1 expression levels are upregulated in various in vitro and in vivo models of hypertrophy and that LMCD1 is necessary and sufficient to induce cardiomyocyte hypertrophy in vitro . We successfully generated a new mouse line with a conditional cardiac knockout of LMCD1. We performed echocardiographic, morphometric, and molecular analysis in these LMCD1-deficient and appropriate control-mice under basic conditions as well as 14 days after transverse aortic banding (TAC)-induced left ventricular (LV) pressure overload. Our aim was to investigate the hypothesis of potential beneficial effects of LMCD1-downregulation in vivo . These knockout (KO)-mice revealed under basic conditions a significant reduction of LMCD1 in the heart to <10% on protein level compared to control (WT)-mice (females and males n=5 each, p<0.001), while anatomic and functional parameters of the heart as well as LMCD1 levels in all other tested organs remained unchanged. Sham-operated KO-mice also showed significantly reduced level of LMCD1 in the LV compared to Sham-operated WT-mice (protein level <20%, p<0.001, n=8). No significant increase of LMCD1 in TAC- compared to Sham-operated KO-mice was found. TAC-operated KO-mice showed no significant differences in heart anatomy and function when compared to TAC-operated WT-mice. However, we determined a consistent trend toward improved heart function (ejection fraction and fractional shortening). Furthermore, TAC-operated KO-mice showed reduced activation of the fetal gene program in LV-tissue compared to TAC-operated WT-mice: mRNA levels of the hypertrophic markers NppA, NppB, and Rcan1-4 were all decreased (WT-TAC n=8 vs. KO-TAC n=10: NppA 8.5±2.0 vs. 5.1±1.5, p<0.05; NppB 1.9±0.2 vs. 1.7±0.3, p=0.093; Rcan1-4 6.0±0.2 vs. 3.2 vs. 0.7, p<0.05), suggesting a protective role of LMCD1-knockout. The reduction of calcineurin (CnA)-responsive Rcan1-4 specifically suggests a protective role of LMCD1-knockout in CnA-dependent signaling. Taken together, our preliminary data reveals protective effects of LMCD1-knockout against TAC-induced hypertrophic signaling. Ongoing experiments focus on effects of LMCD1-knockout on apoptosis and fibrosis and its role in Angiotensin-induced hypertrophy.

scholarly journals Computational Investigation of Transmural Differences in Left Ventricular Contractility

2016 ◽  
Vol 138 (11) ◽  
Author(s):  
Hua Wang ◽  
Xiaoyan Zhang ◽  
Shauna M. Dorsey ◽  
Jeremy R. McGarvey ◽  
Kenneth S. Campbell ◽  
...  
Keyword(s):  
Myocardial Contractility ◽  
Ex Vivo ◽  
Experimental Studies ◽  
Contractile Force ◽  
Left Ventricular ◽  
Lv Function ◽  
Fe Model ◽  
Myocardial Layers ◽  
Best Fit

Myocardial contractility of the left ventricle (LV) plays an essential role in maintaining normal pump function. A recent ex vivo experimental study showed that cardiomyocyte force generation varies across the three myocardial layers of the LV wall. However, the in vivo distribution of myocardial contractile force is still unclear. The current study was designed to investigate the in vivo transmural distribution of myocardial contractility using a noninvasive computational approach. For this purpose, four cases with different transmural distributions of maximum isometric tension (Tmax) and/or reference sarcomere length (lR) were tested with animal-specific finite element (FE) models, in combination with magnetic resonance imaging (MRI), pressure catheterization, and numerical optimization. Results of the current study showed that the best fit with in vivo MRI-derived deformation was obtained when Tmax assumed different values in the subendocardium, midmyocardium, and subepicardium with transmurally varying lR. These results are consistent with recent ex vivo experimental studies, which showed that the midmyocardium produces more contractile force than the other transmural layers. The systolic strain calculated from the best-fit FE model was in good agreement with MRI data. Therefore, the proposed noninvasive approach has the capability to predict the transmural distribution of myocardial contractility. Moreover, FE models with a nonuniform distribution of myocardial contractility could provide a better representation of LV function and be used to investigate the effects of transmural changes due to heart disease.

Abstract 313: STIM1 Silencing Reverses Pressure-overload Induced Cardiac Hypertrophy In Mice

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Ludovic O Bénard ◽  
Daniel S Matasic ◽  
Mathilde Keck ◽  
Anne-Marie Lompré ◽  
Roger J Hajjar ◽  
...  
Keyword(s):  
Ventricular Hypertrophy ◽  
Contractile Function ◽  
Pressure Overload ◽  
Left Ventricular ◽  
Aortic Banding ◽  
Cross Section Area ◽  
Abdominal Aortic ◽  
Section Area

STromal Interaction Molecule 1 (STIM1), a membrane protein of the sarcoplasmic reticulum, has recently been proposed as a positive regulator of cardiomyocyte growth by promoting Ca2+ entry through the plasma membrane and the activation of Ca2+-mediated signaling pathways. We demonstrated that STIM1 silencing prevented the development of left ventricular hypertrophy (LVH) in rats after abdominal aortic banding. Our aim was to study the role of STIM1 during the transition from LVH to heart failure (HF). For experimental timeline, see figure. Transverse Aortic Constriction (TAC) was performed in C57Bl/6 mice. In vivo gene silencing was performed using recombinant Associated AdenoVirus 9 (AAV9). Mice were injected with saline or with AAV9 expressing shRNA control or against STIM1 (shSTIM1) (dose: 1e+11 viral genome), which decreased STIM1 cardiac expression by 70% compared to control. While cardiac parameters were similar between the TAC groups at weeks 3 and 6, shSTIM1 animals displayed a progressive and total reversion of LVH with LV walls thickness returning to values observed in sham mice at week 8. This reversion was associated with the development of significant LV dilation and severe contractile dysfunction, as assessed by echography. Hemodynamic analysis confirmed the altered contractile function and dilation of shSTIM1 animals. Immunohistochemistry showed a trend to more fibrosis. Despite hypertrophic stimuli, there was a significant reduction in cardiac myocytes cross-section area in shSTIM1-treated animals as compared to other TAC mice. This study showed that STIM1 is essential to maintain compensatory LVH and that its silencing accelerates the transition to HF.

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.

scholarly journals Oncofetal Protein CRIPTO Is Involved in Wound Healing and Fibrogenesis in the Regenerating Liver and Is Associated with the Initial Stages of Cardiac Fibrosis

Cells ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3325
Author(s):  
Sofia Karkampouna ◽  
Danny van der Helm ◽  
Mario Scarpa ◽  
Bart van Hoek ◽  
Hein W. Verspaget ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Mouse Models ◽  
Cardiac Fibrosis ◽  
Ex Vivo ◽  
Pressure Overload ◽  
Collagen Type I ◽  
Type I ◽  
Liver Fibrogenesis ◽  
End Stage

Oncofetal protein, CRIPTO, is silenced during homeostatic postnatal life and often re-expressed in different neoplastic processes, such as hepatocellular carcinoma. Given the reactivation of CRIPTO in pathological conditions reported in various adult tissues, the aim of this study was to explore whether CRIPTO is expressed during liver fibrogenesis and whether this is related to the disease severity and pathogenesis of fibrogenesis. Furthermore, we aimed to identify the impact of CRIPTO expression on fibrogenesis in organs with high versus low regenerative capacity, represented by murine liver fibrogenesis and adult murine heart fibrogenesis. Circulating CRIPTO levels were measured in plasma samples of patients with cirrhosis registered at the waitlist for liver transplantation (LT) and 1 year after LT. The expression of CRIPTO and fibrotic markers (αSMA, collagen type I) was determined in human liver tissues of patients with cirrhosis (on a basis of viral hepatitis or alcoholic disease), in cardiac tissue samples of patients with end-stage heart failure, and in mice with experimental liver and heart fibrosis using immuno-histochemical stainings and qPCR. Mouse models with experimental chronic liver fibrosis, induced with multiple shots of carbon tetrachloride (CCl4) and acute liver fibrosis (one shot of CCl4), were evaluated for CRIPTO expression and fibrotic markers. CRIPTO was overexpressed in vivo (Adenoviral delivery) or functionally sequestered by ALK4Fc ligand trap in the acute liver fibrosis mouse model. Murine heart tissues were evaluated for CRIPTO and fibrotic markers in three models of heart injury following myocardial infarction, pressure overload, and ex vivo induced fibrosis. Patients with end-stage liver cirrhosis showed elevated CRIPTO levels in plasma, which decreased 1 year after LT. Cripto expression was observed in fibrotic tissues of patients with end-stage liver cirrhosis and in patients with heart failure. The expression of CRIPTO in the liver was found specifically in the hepatocytes and was positively correlated with the Model for End-stage Liver Disease (MELD) score for end-stage liver disease. CRIPTO expression in the samples of cardiac fibrosis was limited and mostly observed in the interstitial cells. In the chronic and acute mouse models of liver fibrosis, CRIPTO-positive cells were observed in damaged liver areas around the central vein, which preceded the expression of αSMA-positive stellate cells, i.e., mediators of fibrosis. In the chronic mouse models, the fibrosis and CRIPTO expression were still present after 11 weeks, whereas in the acute model the liver regenerated and the fibrosis and CRIPTO expression resolved. In vivo overexpression of CRIPTO in this model led to an increase in fibrotic markers, while blockage of CRIPTO secreted function inhibited the extent of fibrotic areas and marker expression (αSMA, Collagen type I and III) and induced higher proliferation of residual healthy hepatocytes. CRIPTO expression was also upregulated in several mouse models of cardiac fibrosis. During myocardial infarction CRIPTO is upregulated initially in cardiac interstitial cells, followed by expression in αSMA-positive myofibroblasts throughout the infarct area. After the scar formation, CRIPTO expression decreased concomitantly with the αSMA expression. Temporal expression of CRIPTO in αSMA-positive myofibroblasts was also observed surrounding the coronary arteries in the pressure overload model of cardiac fibrosis. Furthermore, CRIPTO expression was upregulated in interstitial myofibroblasts in hearts cultured in an ex vivo model for cardiac fibrosis. Our results are indicative for a functional role of CRIPTO in the induction of fibrogenesis as well as a potential target in the antifibrotic treatments and stimulation of tissue regeneration.

scholarly journals Effect of the proinflammatory cytokine TNF-α on intestinal riboflavin uptake: inhibition mediated via transcriptional mechanism(s)

2018 ◽  
Vol 315 (5) ◽  
pp. C653-C663 ◽  
Author(s):  
Kasin Yadunandam Anandam ◽  
Omar A. Alwan ◽  
Veedamali S. Subramanian ◽  
Padmanabhan Srinivasan ◽  
Rubina Kapadia ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Significant Inhibition ◽  
Mrna Levels ◽  
In Vivo Models ◽  
Uptake Inhibition ◽  
Tnf Α ◽  
Vitro Model ◽  
Factor Α

Riboflavin (RF), is essential for normal cellular metabolism/function. Intestinal RF absorption occurs via a specific carrier-mediated process that involves the apical transporter RFVT-3 ( SLC52A3) and the basolateral RFVT-1 (SLC52A1). Previously, we characterized different cellular/molecular aspects of the intestinal RF uptake process, but nothing is known about the effect of proinflammatory cytokines on the uptake event. We addressed this issue using in vitro, ex vivo, and in vivo models. First, we determined the level of mRNA expression of the human (h)RFVT-3 and hRFVT-1 in intestinal tissue of patients with inflammatory bowel disease (IBD) and observed a markedly lower level compared with controls. In the in vitro model, exposing Caco-2 cells to tumor necrosis factor-α (TNF-α) led to a significant inhibition in RF uptake, an effect that was abrogated upon knocking down TNF receptor 1 (TNFR1). The inhibition in RF uptake was associated with a significant reduction in the expression of hRFVT-3 and -1 protein and mRNA levels, as well as in the activity of the SLC52A3 and SLC52A1 promoters. The latter effects appear to involve Sp1 and NF-κB sites in these promoters. Similarly, exposure of mouse small intestinal enteroids and wild-type mice to TNF-α led to a significant inhibition in physiological and molecular parameters of intestinal RF uptake. Collectively, these findings demonstrate that exposure of intestinal epithelial cells to TNF-α leads to inhibition in RF uptake and that this effect is mediated, at least in part, via transcriptional mechanism(s). These findings may explain the significantly low RF levels observed in patients with IBD.

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