Remodeling In Mice Research Articles

BNIP3 is essential for mitochondrial bioenergetics during adipocyte remodelling in mice.

Adipose tissue is a highly versatile system in which mitochondria in adipocytes undergo significant changes during active tissue remodelling. BCL2/adenovirus E1B 19kDa protein-interacting protein 3 (BNIP3) is a mitochondrial protein and a known mitochondrial quality regulator. In this study, we investigated the role of BNIP3 in adipocytes, specifically under conditions of peroxisome proliferator-activated receptor-γ (PPARγ)-induced adipose tissue remodelling. The expression of BNIP3 was evaluated in 3T3-L1 adipocytes in vitro, C57BL/6 mice fed a high-fat diet and db/db mice in vivo. Mitochondrial bioenergetics was investigated in BNIP3-knockdown adipocytes after rosiglitazone treatment. A putative peroxisome proliferator hormone responsive element (PPRE) was characterised by promoter assay and electrophoretic mobility shift assay (EMSA). The protein BNIP3 was more abundant in brown adipose tissue than white adipose tissue. Furthermore, BNIP3 expression was upregulated by 3T3-L1 pre-adipocyte differentiation, starvation and rosiglitazone treatment. Conversely, BNIP3 expression in adipocytes decreased under various conditions associated with insulin resistance. This downregulation of BNIP3 was restored by rosiglitazone treatment. Knockdown of BNIP3 in adipocytes inhibited rosiglitazone-induced mitochondrial biogenesis and function, partially mediated by the 5' AMP-activated protein kinase (AMPK)-peroxisome proliferator-activated receptor γ, co-activator 1 α (PGC1α) signalling pathway. Rosiglitazone treatment increased the transcription level of Bnip3 in the reporter assay and the presence of the PPRE site in the Bnip3 promoter was demonstrated by EMSA. The protein BNIP3 contributes to the improvement of mitochondrial bioenergetics that occurs on exposure to rosiglitazone. It may be a novel therapeutic target for restoring mitochondrial dysfunction under insulin-resistant conditions.

P62-ZZ Domain Inhibition Prevents MM Cell-Induced Epigenetic Changes at the Runx2 and C/EBPb Promoters

Multiple myeloma bone disease (MMBD) is a paradigm for uncoupled bone remodeling and is characterized by non-healing lytic bone lesions. Osteoblast (OB) function is highly suppressed or absent, persists in the absence of MM cells, and remains a significant cause of skeletal-related events. The persistence of OB suppression in MMBD suggests that MM cells induce repressive epigenetic changes at the Runx2 gene, the key transcription factor required for OB differentiation of bone marrow stromal cells (BMSC), which are preOB. We reported that TNFα is a major suppressor of OB in MMBD that reduces Runx2 levels by inducing Gfi1, a transcriptional repressor of Runx2. Using ChIP analysis of MM-exposed BMSC, we showed that Gfi1 directly binds the Runx2 promoter and recruits the chromatin corepressor HDAC1 to the Runx2 promoter in MM-exposed BMSC, reducing transcriptionally permissive euchromatin marks such as H3K9ac.Recently, we reported that p62 (sequestosome-1) in BMSC is critical for the formation of MM cell-induced signaling complexes that mediate OB suppression and IL-6 production. We found that XRK3F2, a novel inhibitor of the p62 ZZ domain (p62-ZZ), blunted MM cell-induced repression of Runx2 and induction of Gfi1 in BMSC, and induced new bone formation and remodeling in mice with established MMBD, but did not alter normal bone. In the current study, we further evaluated the specificity of XRK3F2's inhibition of p62-ZZ interactions and investigated the mechanism by which blocking p62-ZZ prevents MM-induced suppression of key osteogenic transcription factors in BMSC.We previously showed that TNFα and MM cell-induced IL-6 production by BMSC are both p62 dependent and independent. XRK3F2 blocked TNFα-induced NFκB signaling in BMSC and MM cells, and partially inhibited TNFα-induced IL-6 production by BMSC. We now report that XRK3F2 blunted the TNFα upregulation observed in BMSC after MM cell coculture but did not alter TNFα production in p62 knockout (p62KO) BMSC following coculture with MM cells. TNFα treatment of p62KO BMSCs resulted in minimal induction of IL-6, which was not altered by XRK3F2. Transfection of p62KO BMSC with full-length p62 constructs restored TNFα-induced IL-6 production and XRK3F2's capacity to reduce TNFα-induced IL-6. In contrast, XRK3F2 had no effect on TNFα-induced IL-6 production by p62KO BMSC transfected with p62 constructs lacking p62-ZZ.To further investigate XRK3F2's mechanism of action, we tested if XRK3F2 prevents Gfi1-induced epigenetic suppression of Runx2 by preventing Gfi1's upregulation and binding to Runx2. ChIP analysis of MM exposed BMSC treated with XRK3F2 demonstrated that XRK3F2 reduced MM-induced Gfi1 occupancy of the Runx2 promoter and prevented MM-induced reduction of H3K9ac. Since the region proximal to the Runx2 promoter contains putative C/EBPβ binding sites, we tested if MM-induced p62-ZZ signaling activates C/EBPβ, a transcription factor that regulates OB lineage maturation and IL-6 production in BMSC and plays a role in the upregulation of Gfi1 expression. MM-exposed BMSC had increased enrichment of C/EBPβ at both the Gfi1 gene and the C/EBPβ-regulated Il6 gene, and XRK3F2 reduced upregulation of MM-induced C/EBPβ binding at both the Gfi1 and Il6 genes. We conclude that XRK3F2's reduction of the MM-induced C/EBPβ binding in BMSC results in decreased Gfi1 mRNA expression, and thereby reduces MM-induced Gfi1 occupancy and HDAC1 recruitment at the Runx2 promoter. These results suggest that targeting p62-ZZ in MMBD may reverse C/EBPβ mediated Gfi1 activation, resulting in rescue of the MM cell-induced epigenetic suppression of Runx2 in BMSC, and that next-generation derivatives of XRK3F2 should impact BMSC-supported MM cell survival. DisclosuresSilbermann:Celgene: Research Funding; Amgen: Consultancy. Xie:Oxis Biotech: Consultancy, Membership on an entity's Board of Directors or advisory committees. Roodman:Eli Lilly: Research Funding; Amgen: Consultancy.

Asiatic Acid Attenuates the Progression of Left Ventricular Hypertrophy and Heart Failure Induced by Pressure Overload by Inhibiting Myocardial Remodeling in Mice.

Cardiac structural remodeling, including cardiomyocyte apoptosis, interstitial fibrosis, and inflammation, appears to be a key event associated with the progression of left ventricular hypertrophy and heart failure. Asiatic acid (AA) is a triterpenoid compound extracted from Centella asiatica that exhibits antiapoptotic, antifibrotic, and anti-inflammatory activities. In the present study, a transverse aortic constriction (TAC) model was created in mice to mimic the progression of hypertrophy (2 weeks post-TAC) and heart failure (4 weeks post-TAC) to investigate whether the potential therapeutic drug AA ameliorates hypertrophy progression and which mechanisms are involved in this amelioration. Our results demonstrated that AA markedly inhibited the process of progression induced by pressure overload. The increases cardiomyocyte apoptosis and interstitial fibrosis, and inflammatory responses were significantly suppressed by AA. Our investigation revealed that this inhibitory effect was mediated by blocking the activation of both mitochondrial and death receptor-dependent apoptotic signaling pathways. Additional experiments demonstrated that AA attenuated fibrosis by blocking both transforming growth factor-β1/Smad and interleukin-6, signaling activation. Consequently, these findings indicated that AA attenuated pathological cardiac structural remodeling and preserved cardiac function via multiple intracellular signaling pathways in response to cardiac stimuli.

Abstract 19335: Rescue of Cardiac Function Lost Due to Congenital Defect in Proteasome Heterogeneity

The ubiquitin-proteasome system is a major regulator of protein homeostasis in health and disease by targeted proteolysis. Recent findings show that the heterogeneity of proteasome complexes is dynamically altered via elevated incorporation of non-essential proteasome subunits in the pathogenesis of cardiac remodeling. However, the impact of this regulatory event on cardiac remodeling is not known. Therefore, aim of the study was to determine the influence of the non-essential proteasome subunit Lmp2 on cardiac remodeling induced by chronic catecholamine exposure. Wild-type mice subjected to 30mg/kg isoproterenol for 7 days developed cardiac hypertrophy with increased cardiac function (fractional shortening/FS: +18% vs. pre-treatment). In hearts of these mice, Lmp2 showed increased abundance and incorporation in proteasome complexes. Adult mice lacking Lmp2 congenitally seem phenotypically indistinguishable from wild-types, but developed exacerbated cardiac hypertrophy with decreased cardiac function (FS: -27% vs. wt) upon continuous isoproterenol stimulation. Myocardial transfer of the gene encoding Lmp2 via adeno-associated virus in adult mice resulted in the expression of its processed form comparable to wild-type levels with no obvious phenotypic effects under unstimulated conditions. Upon catecholamine challenge, increasing levels of processed Lmp2 were detected in hypertrophied hearts, suggesting induced functional incorporation in proteasome complexes similar to observations previously made in wild-type animals. Re-expression of Lmp2 reduced the extent of cardiac remodeling in mice congenitally lacking this subunit and rescued cardiac function at least in part (FS: +13% vs. treated virus control). In conclusion, the study demonstrates for the first time that induced expression of the non-essential proteasome subunit Lmp2 is a regulatory mechanism of targeted proteolysis, which mitigates cardiac remodeling and contributes to maintaining cardiac function.

Leukemia Inhibitory Factor (LIF) Inhibition during Mid-Gestation Impairs Trophoblast Invasion and Spiral Artery Remodelling during Pregnancy in Mice.

The placenta forms the interface between the maternal and fetal circulation and is critical for the establishment of a healthy pregnancy. Trophoblast cell proliferation, migration and invasion into the endometrium are fundamental events in the initiation of placentation. Leukemia inhibitory factor (LIF) has been shown to promote trophoblast invasion in vitro, however its precise role in trophoblast invasion in vivo is unknown. We hypothesized that LIF would be required for normal trophoblast invasion and spiral artery remodeling in mice. Both LIF and its receptor (LIFRα) co-localized with cytokeratin-positive invasive endovascular extravillous trophoblasts (EVT) in mouse implantation sites during mid-gestation. Temporally blocking LIF action during specific periods of placental development via administration of our unique LIFRα antagonist, PEGLA, resulted in abnormal trophoblast invasion and impaired spiral artery remodeling compared to PEG control. PEGLA-treated mouse decidual vessels were characterized by retention of α-smooth muscle actin (αSMA)-positive vascular smooth muscle cells (VSMCs), while PEG control decidual vessels were remodelled by cytokeratin-positive trophoblasts. LIF blockade did not alter F4/80-positive decidual macrophage numbers between treatment groups, but resulted in down-regulation of decidual transcript levels of monocyte chemoattractant protein-1 (MCP-1) and interleukin-10 (IL-10), which are important immune cell activation factors that promote spiral artery remodeling during pregnancy. Our data suggest that LIF plays an important role in trophoblast invasion in vivo and may facilitate trophoblast-decidual-immune cell cross talk to enable adequate spiral artery remodeling.

The orphan nuclear receptor Nur77 inhibits low shear stress-induced carotid artery remodeling in mice.

Shear stress, particularly low and oscillatory shear stress, plays a critical pathophysiological role in vascular remodeling-related cardiovascular diseases. Growing evidence suggests that the orphan nuclear receptor Nur77 [also known as TR3 or nuclear receptor subfamily 4, group A, member 1 (NR4A1)] is expressed in diseased human vascular tissue and plays an important role in vascular physiology and pathology. In the present study, we used a mouse model of flow-dependent remodeling by partial ligation of the left common carotid artery (LCCA) to define the exact role of Nur77 in vascular remodeling induced by low shear stress. Following vascular remodeling, Nur77 was highly expressed in neointimal vascular smooth muscle cells (VSMCs) in the ligated carotid arteries. The reactive oxygen species (ROS) levels were elevated in the remodeled arteries in vivo and in primary rat VSMCs in vitro following stimulation with platelet-derived growth factor (PDGF). Further in vitro experiments revealed that Nur77 expression was rapidly increased in the VSMCs following stimulation with PDGF and H2O2, whereas treatment with N-acetyl cysteine (NAC, a ROS scavenger) reversed the increase in the protein level of Nur77 induced by H2O2. Moreover, Nur77 overexpression markedly inhibited the proliferation and migration of VSMCs, induced by PDGF. Finally, to determine the in vivo role of Nur77 in low shear stress-induced vascular remodeling, wild-type (WT) and Nur77-deficient mice were subjected to partial ligation of the LCCA. Four weeks following surgery, in the LCCAs of the Nur77-deficient mice, a significant increase in the intima-media area and carotid intima-media thickness was noted, as well as more severe elastin disruption and collagen deposition compared to the WT mice. Immunofluorescence staining revealed an increase in VSMC proliferation [determined by the expression of proliferating cell nuclear antigen (PCNA)] and matrix metalloproteinase 9 (MMP-9) production in the Nur77-deficient mice. There was no difference in the number of intimal apoptotic cells between the groups. Taken together, our results indicate that Nur77 may be a sensor of oxidative stress and an inhibitor of vascular remodeling induced by low shear stress. Nur77, as well as its downstream cell signals, may thus be a potential therapeutic target for the suppression of vascular remodeling.

Cardiomyocyte-enriched protein CIP protects against pathophysiological stresses and regulates cardiac homeostasis.

Cardiomyopathy is a common human disorder that is characterized by contractile dysfunction and cardiac remodeling. Genetic mutations and altered expression of genes encoding many signaling molecules and contractile proteins are associated with cardiomyopathy; however, how cardiomyocytes sense pathophysiological stresses in order to then modulate cardiac remodeling remains poorly understood. Here, we have described a regulator in the heart that harmonizes the progression of cardiac hypertrophy and dilation. We determined that expression of the myocyte-enriched protein cardiac ISL1-interacting protein (CIP, also known as MLIP) is reduced in patients with dilated cardiomyopathy. As CIP is highly conserved between human and mouse, we evaluated the effects of CIP deficiency on cardiac remodeling in mice. Deletion of the CIP-encoding gene accelerated progress from hypertrophy to heart failure in several cardiomyopathy models. Conversely, transgenic and AAV-mediated CIP overexpression prevented pathologic remodeling and preserved cardiac function. CIP deficiency combined with lamin A/C deletion resulted in severe dilated cardiomyopathy and cardiac dysfunction in the absence of stress. Transcriptome analyses of CIP-deficient hearts revealed that the p53- and FOXO1-mediated gene networks related to homeostasis are disturbed upon pressure overload stress. Moreover, FOXO1 overexpression suppressed stress-induced cardiomyocyte hypertrophy in CIP-deficient cardiomyocytes. Our studies identify CIP as a key regulator of cardiomyopathy that has potential as a therapeutic target to attenuate heart failure progression.

GW26-e2456 Orphan Nuclear Receptor Nur77 deletion exacerbates low shear stress-induced carotid artery remodeling in mice

Carotid artery remodeling, also defined as intima-media thickening, is an important predictive indicator for human cardiovascular disease. Chronic changes in shear stress contribute to vascular remodeling. Orphan nuclear receptor Nur77 is expressed in diseased human vascular tissue, and plays a

Proteolytic regulation of synaptic plasticity in the mouse primary visual cortex: analysis of matrix metalloproteinase 9 deficient mice.

The extracellular matrix (ECM) is known to play important roles in regulating neuronal recovery from injury. The ECM can also impact physiological synaptic plasticity, although this process is less well understood. To understand the impact of the ECM on synaptic function and remodeling in vivo, we examined ECM composition and proteolysis in a well-established model of experience-dependent plasticity in the visual cortex. We describe a rapid change in ECM protein composition during Ocular Dominance Plasticity (ODP) in adolescent mice, and a loss of ECM remodeling in mice that lack the extracellular protease, matrix metalloproteinase-9 (MMP9). Loss of MMP9 also attenuated functional ODP following monocular deprivation (MD) and reduced excitatory synapse density and spine density in sensory cortex. While we observed no change in the morphology of existing dendritic spines, spine dynamics were altered, and MMP9 knock-out (KO) mice showed increased turnover of dendritic spines over a period of 2 days. We also analyzed the effects of MMP9 loss on microglia, as these cells are involved in extracellular remodeling and have been recently shown to be important for synaptic plasticity. MMP9 KO mice exhibited very limited changes in microglial morphology. Ultrastructural analysis, however, showed that the extracellular space surrounding microglia was increased, with concomitant increases in microglial inclusions, suggesting possible changes in microglial function in the absence of MMP9. Taken together, our results show that MMP9 contributes to ECM degradation, synaptic dynamics and sensory-evoked plasticity in the mouse visual cortex.

Obligatory Role for B Cells in the Development of Angiotensin II-Dependent Hypertension.

Clinical hypertension is associated with raised serum IgG antibodies. However, whether antibodies are causative agents in hypertension remains unknown. We investigated whether hypertension in mice is associated with B-cell activation and IgG production and moreover whether B-cell/IgG deficiency affords protection against hypertension and vascular remodeling. Angiotensin II (Ang II) infusion (0.7 mg/kg per day; 28 days) was associated with (1) a 25% increase in the proportion of splenic B cells expressing the activation marker CD86, (2) an 80% increase in splenic plasma cell numbers, (3) a 500% increase in circulating IgG, and (4) marked IgG accumulation in the aortic adventitia. In B-cell-activating factor receptor-deficient (BAFF-R(-/-)) mice, which lack mature B cells, there was no evidence of Ang II-induced increases in serum IgG. Furthermore, the hypertensive response to Ang II was attenuated in BAFF-R(-/-) (Δ30±4 mm Hg) relative to wild-type (Δ41±5 mm Hg) mice, and this response was rescued by B-cell transfer. BAFF-R(-/-) mice displayed reduced IgG accumulation in the aorta, which was associated with 80% fewer aortic macrophages and a 70% reduction in transforming growth factor-β expression. BAFF-R(-/-) mice were also protected from Ang II-induced collagen deposition and aortic stiffening (assessed by pulse wave velocity analysis). Finally, like BAFF-R deficiency, pharmacological depletion of B cells with an anti-CD20 antibody attenuated Ang II-induced hypertension by ≈35%. Hence, these studies demonstrate that B cells/IgGs are crucial for the development of Ang II-induced hypertension and vessel remodeling in mice. Thus, B-cell-targeted therapies-currently used for autoimmune diseases-may hold promise as future treatments for hypertension.

Cardiac melanocytes influence atrial reactive oxygen species involved with electrical and structural remodeling in mice.

Cardiac melanocyte-like cells (CMLCs) contribute to atrial arrhythmias when missing the melanin synthesis enzyme dopachrome tautomerase (Dct). While scavenging reactive oxygen species (ROS) in Dct-null mice partially suppressed atrial arrhythmias, it remains unclear if CMLCs influence atrial ROS and structure or if the electrical response of CMLCs to ROS differs from that of atrial myocytes. This study is designed to determine if CMLCs contribute to overall atrial oxidative stress or structural remodeling, and if ROS affects the electrophysiology of CMLCs differently than atrial myocytes. Immunohistochemical analysis showed higher expression of the oxidative marker 8-hydroxy-2′-deoxyguanosine in Dct-null atria versus Dct-heterozygous (Dct-het) atria. Exposing isolated CMLCs from Dct-het and Dct-null mice to hydrogen peroxide increased superoxide anion more in Dct-null CMLCs. Trichrome staining showed increased fibrosis in Dct-null atria, and treating Dct-null mice with the ROS scavenger Tempol reduced atrial fibrosis. Action potential recordings from atrial myocytes and isolated Dct-het and Dct-null CMLCs in response to hydrogen peroxide showed that the EC50 for action potential duration (APD) prolongation of Dct-null CMLCs was 8.2 ± 1.7 μmol/L versus 16.8 ± 2.0 μmol/L for Dct-het CMLCs, 19.9 ± 2.1 μmol/L for Dct-null atrial myocytes, and 20.5 ± 1.9 μmol/L for Dct-het atrial myocytes. However, APD90 was longer in CMLCs versus atrial myocytes in response to hydrogen peroxide. Hydrogen peroxide also induced more afterdepolarizations in CMLCs compared to atrial myocytes. These studies suggest that Dct within CMLCs contributes to atrial ROS balance and remodeling. ROS prolongs APD to a greater extent and induces afterdepolarizations more frequently in CMLCs than in atrial myocytes.

MAGED1 Is a Negative Regulator of Bone Remodeling in Mice

Melanoma antigen family D1 (MAGED1), an important adaptor protein, has been shown to ubiquitously express and play critical roles in many aspects of cellular events and physiological functions. However, its role in bone remodeling remains unknown. We, therefore, analyzed the bone phenotype of Maged1-deficient mice. Maged1-deficient mice displayed a significant osteoporotic phenotype with a marked decrease in bone density and deterioration of trabecular architecture. Histomorphometric analysis demonstrated an increased mineral apposition rate as well as increased osteoclast number and surface in Maged1 knockout mice. At the cellular level, Maged1-deficient osteoblasts exhibited an increased proliferation rate and accelerated differentiation. MAGED1 deficiency also caused a promotion in osteoclastogenesis, and that was attributed to the cell autonomous acceleration of differentiation in osteoclasts and an increased receptor activator of NF-κB ligand/osteoprotegerin ratio, a major index ofosteoclastogenesis, in osteoblasts. Thus, we identified MAGED1 as a novel regulator of osteoblastogenesis, osteoclastogenesis, and bone remodeling in a mouse model.

P33. Decreasing of placental progesterone induced blocking factor expression and spiral artery remodeling disturbance in mice preeclampsia model

Introduction Preeclampsia is a major cause of morbidity and mortality in our developing country. The biggest obstacle in the high prevalence of preeclampsia and its management is due to lack of knowledge in preeclampsia pathologic mechanism. Progesterone is an important pregnancy hormone that has immunomodulatory effect by inducing progesterone induced blocking factor (PIBF) release, due to binding of progesterone with its receptor in lymphocyte. PIBF inhibits cytolytic NK cells activity and inducing T-helper 2 cytokine dominant while on contrary, preeclampsia has a condition of T-helper 1 cytokine dominant and increase of NK cells cytolytic activity. This was the first study to evaluated PIBF expression directly on the placenta when the pathogenesis of preeclampsia occurred after completion of vascular remodeling in animal models. Objective The objectives of this study were to compare placental PIBF expression, spiral artery wall thickness as characteristic of vascular remodeling disturbance and investigated correlation between both in mice preeclampsia model. Methods This experimental study used 32 pregnant mus musculus mice and randomly divided to normal group and preeclampsia model group. Our preeclampsia model was created by injecting anti-Qa2 (anti HLA-G) 10 ng from 1st until 4th day of pregnancy, to reduced HLA-G expression. Termination of both groups were performed after completion of spiral artery remodeling in mice by day 16th of pregnancy followed by immunohistochemistry examination for PIBF expression using immunoreactive score and spiral artery wall thickness measurement. Ethical clearance was taken from Medical Veterinary Faculty ethics commission. Difference and correlation were analysed using SPSS 20. Probability values Result In the result, PIBF were expressed in trophoblast, decidual and lymphocyte cells in placental tissue. The placental PIBF expression on preeclampsia model (2.01 ± 1.14) was significantly reduced (p ± 0.01) compared with control (3.99 ± 2.53). There was a significant increase of spiral artery wall thickness (p ± 0.001) in preeclampsia model (20.70 ± 5.93 micrometers) compared with control (9.98 ± 3.36 micrometers). There was a significant association (p ± 0.001) with negative correlation (rho/Pearson correlation = −0.623) between placental PIBF expression and the spiral artery wall thickness. Conclusion We concluded a decreased expression of placental PIBF and the increase of spiral artery wall thickness as a characteristic of spiral artery remodeling disturbance in mice model of preeclampsia, with negative correlation between placental PIBF expression and spiral artery wall thickness.

Ablation of C/EBP homologous protein increases the acute phase mortality and doesn't attenuate cardiac remodeling in mice with myocardial infarction

Endoplasmic reticulum stress is a proapoptotic and profibrotic stimulus. Ablation of C/EBP homologous protein (CHOP) is reported to reverse cardiac dysfunction by attenuating cardiac endoplasmic reticulum stress in mice with pressure overload or ischemia/reperfusion, but it is unclear whether loss of CHOP also inhibits cardiac remodeling induced by permanent-infarction. In mice with permanent ligation of left coronary artery, we found that ablation of CHOP increased the acute phase mortality. For the mice survived to 4 weeks, left ventricular anterior (LV) wall thickness was larger in CHOP knockout mice than in the wildtype littermates, while no difference was noted on posterior wall thickness, LV dimensions, LV fractional shortening and ejection fraction. Similarly, invasive assessment of LV hemodynamics, morphological analysis of heart and lung weight indexes, myocardial fibrosis and TUNEL-assessed apoptosis showed no significant differences between CHOP knockout mice and their wildtype ones, while in mice with ischemia for 45 min and reperfusion for 1 week, myocardial fibrosis and apoptosis in the infarct area were significantly attenuated in CHOP knockout mice. These findings indicate that ablation of CHOP doesn't ameliorate cardiac remodeling induced by permanent-myocardial infarction, which implicates that early reperfusion is a prerequisite for ischemic myocardium to benefit from CHOP inhibition.

Structural and ultrastructural evaluation of the aortic wall after transplantation of bone marrow-derived cells (BMCs) in a model for atherosclerosis.

Stem cells are characterized by their ability to differentiate into multiple cell lineages and display the paracrine effect. The aim of this work was to evaluate the effect of therapy with bone marrow-derived cells (BMCs) on glucose, lipid metabolism, and aortic wall remodeling in mice through the administration of a high-fat diet and subsequent BMCs transplantation. C57BL/6 mice were fed a control diet (CO group) or an atherogenic diet (AT group). After 16 weeks, the AT group was divided into 4 subgroups: an AT 14 days group and AT 21 days group that were given an injection of vehicle and sacrificed after 14 and 21 days, respectively, and an AT-BMC 14 days group and AT-BMC 21 days group that were given an injection of BMCs and sacrificed after 14 and 21 days, respectively. The BMCs transplant had reduced blood glucose, triglycerides, and total cholesterol. There was no significant difference in relation to body mass between the transplanted groups and non-transplanted groups, and all were different than CO. There was no significant difference in the glycemic curve among AT 14 days, AT-BMC 14 days, and AT 21 days, and these were different than the CO and the AT-BMC 21 days groups. The increased thickness of the aortic wall was observed in all atherogenic groups, but was significantly smaller in group AT-BMC 21 days compared to AT 14 days and AT 21 days. Vacuoles in the media tunic, delamination and the thinning of the elastic lamellae were observed in AT 14 days and AT 21 days. The smallest number of these was displayed on the AT-BMC 14 days and AT-BMC 21 days. Marking to CD105, CD133, and CD68 were observed in AT 14 days and AT 21 days. These markings were not observed in AT-BMC 14 days or in AT-BMC 21 days. Electron micrographs show the beneficial remodeling in AT-BMC 14 days and AT-BMC 21 days, and the structural organization was similar to the CO group. Vesicles of pinocytosis, projection of smooth muscle cells, and delamination of the internal elastic lamina are seen in groups AT 14 days and AT 21 days. Endothelial cells were preserved, and regular and continuous contour in internal elastic lamelae were observed in the CO, the AT-BMC 14 days, and AT-BMC 21 days groups. In conclusion, in an atherosclerotic model using mice and atherogenic diet, the injection of BMCs improves glucose, lipid metabolism, and causes a beneficial remodeling of the aortic wall.

Abstract 264: Circulating Tnni3k Levels Are Useful Diagnosis Biomarker for Acute Ischemic Myocardial Diseases

Our recent data showed that TNNI3K, a MAP kinase specifically expressed in cardiac muscles and interacted with cardiac troponin I, TNNI3K high-expression enhanced cardiac performance, attenuated ischemia-induced ventricular remodeling in mice with myocardial infarction, and protected the myocardium from ischemic injury. In the present study, availability of circulating TNNI3K level was investigated using anti-TNNI3K polyclonal antibodies with ELISA, in patients diagnosed as AMI, chronic heart failure and acute renal failure; and in healthy volunteers groups. Data shown that circulating TNNI3K levels were significantly higher in AMI when compared with other two groups (p<0.001), indicating that measurement of circulating TNNI3K is a novel and useful diagnosing tool for AMI. Then, we made an anti-TNNI3K monoclonal antibody to investigate whether circulating TNNI3K levels play the same role for diagnosis of ischemic myocardial diseases, the availability of serum TNNI3K level was investigated with anti-TNNI3K monoclonal-antibodies in AMI, chronic heart failure and acute renal failure patients, and in healthy volunteers respectively. Data shown that circulating TNNI3K levels were significantly higher in AMI (p<0.001) and sensitivity and specificity are higher, ROC curve is more best than that of polyclonal antibodies, indicating that measurement of circulating TNNI3K level using the monoclonal-antibodies may be a novel and useful tool to diagnose AMI. Furthermore, both ELISA and gold colloid methods are used to observe their sensitivity and specificity. Results showed that the sensitivity and specificity of anti-TNNI3K monoclonal antibody were higher than other biomarkers anti-TNNI3K monoclonal antibody and the measurment time in the gold colloid method is significantly shortened when compared with using ELISA method. In conclusion, using TNNI3K as a molecular target is a new potential approach for developing therapeutic or diagnostic agents for ischemic cardiac diseases by means of molecular biological techniques.

Successful serial imaging of the mouse cerebral arteries using conventional 3-T magnetic resonance imaging.

Serial imaging studies can be useful in characterizing the pathologic and physiologic remodeling of cerebral arteries in various mouse models. We tested the feasibility of using a readily available, conventional 3-T magnetic resonance imaging (MRI) to serially image cerebrovascular remodeling in mice. We utilized a mouse model of intracranial aneurysm as a mouse model of the dynamic, pathologic remodeling of cerebral arteries. Aneurysms were induced by hypertension and a single elastase injection into the cerebrospinal fluid. For the mouse cerebrovascular imaging, we used a conventional 3-T MRI system and a 40-mm saddle coil. We used non-enhanced magnetic resonance angiography (MRA) to detect intracranial aneurysm formation and T2-weighted imaging to detect aneurysmal subarachnoid hemorrhage. A serial MRI was conducted every 2 to 3 days. MRI detection of aneurysm formation and subarachnoid hemorrhage was compared against the postmortem inspection of the brain that was perfused with dye. The imaging times for the MRA and T2-weighted imaging were 3.7±0.5 minutes and 4.8±0.0 minutes, respectively. All aneurysms and subarachnoid hemorrhages were correctly identified by two masked observers on MRI. This MRI-based serial imaging technique was useful in detecting intracranial aneurysm formation and subarachnoid hemorrhage in mice.

Connexin 43 deficiency accelerates skin wound healing and extracellular matrix remodeling in mice

BackgroundCellular channels composed of connexin 43 are known to act as key players in the life cycle of the skin and consequently to underlie skin repair. ObjectiveThis study was specifically set up to investigate the suite of molecular mechanisms driven by connexin 43-based channels on wound healing. MethodsTo this end, a battery of parameters, including re-epithelialization, neovascularization, collagen deposition and extracellular matrix remodeling, was monitored over time during experimentally induced skin repair in heterozygous connexin 43 knockout mice. ResultsIt was found that connexin 43 deficiency accelerates re-epithelialization and wound closure, increases proliferation and activation of dermal fibroblasts, and enhances the expression of extracellular matrix remodeling mediators. ConclusionThese data substantiate the notion that connexin 43 may represent an interesting therapeutic target in dermal wound healing.

Retraction notice to: Epression of MRTF-A and AQP1 plays important roles in pathological vascular remodeling.

At my request the paper entitled ‘The Expression of MRTF-A and AQP1 Play Important Roles in the Pathological Vascular Remodeling’ Asian Pac J Cancer Prev, 16, 1375-83 has been retracted. The reason was a charge of plagiarism with regard to the paper entitled ‘Reciprocal expression of MRTF-A and myocardin is crucial for pathological vascular remodelling in mice’ published earlier in EMBO Journal (EMBO J. 2012 Nov 28;31(23):4428-40. doi: 10.1038/emboj.2012.296. Epub 2012 Oct 26.). I am very sorry that this occurred but I sincerely believe this was due to negligence on the part of the translation company that I trusted to make my manuscript ready for submission.

Chronic Allergic Pulmonary Inflammation is Aggravated in Angiotensin‐(1‐7) Mas Receptor Knockout Mice

Angiotensin‐(1‐7)/Mas receptor axis of the renin‐angiotensin system is associated with attenuation of different inflammatory processes. In this study, we investigated the involvement of Mas receptor in the inflammation and airway remodelling in a model of chronic allergic pulmonary inflammation induced by ovalbumin (OVA). FVBN mice groups: Mas KO control (Mas‐/‐CTRL), Mas KO sensitized with OVA (Mas‐/‐OVA), WT control (Mas+/+CTRL) and WT sensitized with OVA (Mas+/+OVA). The allergic groups received 4 doses of OVA (20µg/mice, i.p.) 14 days apart. After the 2nd sensitization, mice were nebulized with OVA (1% for 30 min; 3 times/week for 4 weeks) or saline (CTRL). Mice were sacrificed 72h after the last nebulization. Mas+/+OVA did not develop inflammation or pulmonary remodelling, as it is observed with this protocol in BalbC mice. However, Mas‐/‐OVA showed a worse performance in the maximum load exercise test and presented a significant increase in inflammatory cell infiltrate in the lung, collagen deposition in the airways, increased thickening of the alveolar parenchyma, increased thickening of the smooth muscle layer of the pulmonary arterioles and hypertrophy of the cardiomyocyte of the right ventricle. Furthermore, Mas‐/‐OVA showed an increase in ERK1/2 and SAPK/JNK phosphorylation and an increase in pro‐inflammatory cytokine (IL13) and chemokines (MCP‐1/CCL2 and RANTES/CCL5) in the lungs. These data indicate that genetic deletion of Mas receptor aggravates lung inflammation and remodelling in mice subjected to a model of chronic asthma.