Multidisciplinary Team-Based Palliative Care for Heart Failure and Food Intake at the End of Life.

Traditionally, patients with end-stage heart failure (HF) have rarely been involved in end-of-life care (EOLC) discussions in Japan. The purpose of this study was to examine the impact of HF-specific palliative care team (HF-PCT) activities on EOLC discussions with patients, HF therapy and care, and food intake at the end of life. We retrospectively analyzed 52 consecutive patients with HF (mean age, 70 ± 15 years; 42% female) who died at our hospital between May 2013 and July 2020 and divided them into two groups: before (Era 1, n = 19) and after (Era 2, n = 33) the initiation of HF-PCT activities in June 2015. Compared to Era 1, Era 2 showed a decrease in invasive procedures, an increase in opioid and non-intubating sedative use for symptom relief, improved quality of meals at the end of life, and an increase in participation in EOLC discussions. The administration of artificial nutrition in the final three days was associated with non-ischemic cardiomyopathy etiology, the number of previous hospitalizations for HF, and multidisciplinary EOLC discussion support. HF-PCT activities may provide an opportunity to discuss EOLC with patients, reduce the burden of physical and psychological symptoms, and shift the goals of end-of-life nutritional intake to ensure comfort and quality of life.

Role of Macrophage Socs3 in the Pathogenesis of Aortic Dissection.

BACKGROUND: Aortic dissection (AD) is a life-threatening medical emergency caused by the abrupt destruction of the intimomedial layer of the aortic walls. Given that previous studies have reported the involvement of proinflammatory cytokine interleukin-6 in AD pathogenesis, we investigated the role of signal transduction and activator of transcription 3 signaling, a downstream pathway of interleukin-6 in macrophages in pathogenesis of AD. METHODS AND RESULTS: We characterized the pathological and molecular events triggered by aortic stress, which can lead to AD. Aortic stress on the suprarenal aorta because of infrarenal aorta stiffening and angiotensin II infusion for 1 week caused focal medial rupture at the branching point of the celiac trunk and superior mesenteric artery. This focal medial rupture healed in 6 weeks in wild-type (WT) mice, but progressed to AD in mice with macrophage-specific deletion of Socs3 gene (mSocs3-KO). mSocs3-KO mice showed premature activation of cell proliferation, an inflammatory response, and skewed differentiation of macrophages toward the tissue-destructive phenotype. Concomitantly, they showed aberrant phenotypic modulation of smooth muscle cells and transforming growth factor beta signaling, which are likely to participate in tissue repair. Human AD samples revealed signal transduction and activator of transcription 3 activation in adventitial macrophages adjacent to the site of tissue destruction. CONCLUSIONS: These findings suggest that AD development is preceded by focal medial rupture, in which macrophage Socs3 maintains proper inflammatory response and differentiation of SMCs, thus promoting fibrotic healing to prevent tissue destruction and AD development. Understanding the sequence of the pathological and molecular events preceding AD development will help predict and prevent AD development and progression.

Disturbance of cardiac gene expression and cardiomyocyte structure predisposes Mecp2-null mice to arrhythmias.

Methyl-CpG-binding protein 2 (MeCP2) is an epigenetic regulator of gene expression that is essential for normal brain development. Mutations in MeCP2 lead to disrupted neuronal function and can cause Rett syndrome (RTT), a neurodevelopmental disorder. Previous studies reported cardiac dysfunction, including arrhythmias in both RTT patients and animal models of RTT. In addition, recent studies indicate that MeCP2 may be involved in cardiac development and dysfunction, but its role in the developing and adult heart remains unknown. In this study, we found that Mecp2-null ESCs could differentiate into cardiomyocytes, but the development and further differentiation of cardiovascular progenitors were significantly affected in MeCP2 deficiency. In addition, we revealed that loss of MeCP2 led to dysregulation of endogenous cardiac genes and myocardial structural alterations, although Mecp2-null mice did not exhibit obvious cardiac functional abnormalities. Furthermore, we detected methylation of the CpG islands in the Tbx5 locus, and showed that MeCP2 could target these sequences. Taken together, these results suggest that MeCP2 is an important regulator of the gene-expression program responsible for maintaining normal cardiac development and cardiomyocyte structure.

Cardiac-Specific SOCS3 Deletion Prevents In Vivo Myocardial Ischemia Reperfusion Injury through Sustained Activation of Cardioprotective Signaling Molecules.

Myocardial ischemia reperfusion injury (IRI) adversely affects cardiac performance and the prognosis of patients with acute myocardial infarction. Although myocardial signal transducer and activator of transcription (STAT) 3 is potently cardioprotective during IRI, the inhibitory mechanism responsible for its activation is largely unknown. The present study aimed to investigate the role of the myocardial suppressor of cytokine signaling (SOCS)-3, an intrinsic negative feedback regulator of the Janus kinase (JAK)-STAT signaling pathway, in the development of myocardial IRI. Myocardial IRI was induced in mice by ligating the left anterior descending coronary artery for 1 h, followed by different reperfusion times. One hour after reperfusion, the rapid expression of JAK-STAT-activating cytokines was observed. We precisely evaluated the phosphorylation of cardioprotective signaling molecules and the expression of SOCS3 during IRI and then induced myocardial IRI in wild-type and cardiac-specific SOCS3 knockout mice (SOCS3-CKO). The activation of STAT3, AKT, and ERK1/2 rapidly peaked and promptly decreased during IRI. This decrease correlated with the induction of SOCS3 expression up to 24 h after IRI in wild-type mice. The infarct size 24 h after reperfusion was significantly reduced in SOCS3-CKO compared with wild-type mice. In SOCS3-CKO mice, STAT3, AKT, and ERK1/2 phosphorylation was sustained, myocardial apoptosis was prevented, and the expression of anti-apoptotic Bcl-2 family member myeloid cell leukemia-1 (Mcl-1) was augmented. Cardiac-specific SOCS3 deletion led to the sustained activation of cardioprotective signaling molecules including and prevented myocardial apoptosis and injury during IRI. Our findings suggest that SOCS3 may represent a key factor that exacerbates the development of myocardial IRI.

ETS transcription factor ETV2 directly converts human fibroblasts into functional endothelial cells.

Transplantation of endothelial cells (ECs) is a promising therapeutic approach for ischemic disorders. In addition, the generation of ECs has become increasingly important for providing vascular plexus to regenerated organs, such as the liver. Although many attempts have been made to generate ECs from pluripotent stem cells and nonvascular cells, the minimum number of transcription factors that specialize in directly inducing vascular ECs remains undefined. Here, by screening 18 transcription factors that are important for both endothelial and hematopoietic development, we demonstrate that ets variant 2 (ETV2) alone directly converts primary human adult skin fibroblasts into functional vascular endothelial cells (ETVECs). In coordination with endogenous FOXC2 in fibroblasts, transduced ETV2 elicits expression of multiple key endothelial development factors, including FLI1, ERG, and TAL1, and induces expression of endothelial functional molecules, including EGFL7 and von Willebrand factor. Consequently, ETVECs exhibits EC characteristics in vitro and forms mature functional vasculature in Matrigel plugs transplanted in NOD SCID mice. Furthermore, ETVECs significantly improve blood flow recovery in a hind limb ischemic model using BALB/c-nu mice. Our study indicates that the creation of ETVECs provides further understanding of human EC development induced by ETV2.

Omentin prevents myocardial ischemic injury through AMP-activated protein kinase- and Akt-dependent mechanisms.

OBJECTIVES: This study examined the impact of omentin on myocardial injury in a mouse model of ischemia/reperfusion (I/R) and explored its underlying mechanisms. BACKGROUND: Obesity is a major risk factor for ischemic heart disease. Omentin is a circulating adipokine that is down-regulated by obesity. METHODS: In patients who underwent successful reperfusion treatment after acute myocardial infarction, cardiac function and perfusion defect were assessed by using scintigraphic images. Mice were subjected to myocardial ischemia followed by reperfusion. RESULTS: This study found that high levels of plasma omentin were associated with improvement of heart damage and function after reperfusion therapy in patients with acute myocardial infarction. Systemic administration of human omentin to mice led to a reduction in myocardial infarct size and apoptosis after I/R, which was accompanied by enhanced phosphorylation of AMP-activated protein kinase (AMPK) and Akt in the ischemic heart. Fat-specific overexpression of human omentin also resulted in reduction of infarct size after I/R. Blockade of AMPK or Akt activity reversed omentin-induced inhibition of myocardial ischemic damage and apoptosis in mice. In cultured cardiomyocytes, omentin suppressed hypoxia/reoxygenation-induced apoptosis, which was blocked by inactivation of AMPK or Akt. CONCLUSIONS: Our data indicate that omentin functions as an adipokine that ameliorates acute ischemic injury in the heart by suppressing myocyte apoptosis through both AMPK- and Akt-dependent mechanisms.

Protective role of JAK/STAT signaling against renal fibrosis in mice with unilateral ureteral obstruction.

Inflammation is involved in renal fibrosis, a final common pathway for kidney diseases. To clarify how JAK/STAT/SOCS system was involved in renal fibrosis, UUO was induced in BALB/c or SOCS3(+/-) mice in the presence or absence of JAK inhibitor-incorporated nanoparticle (pyridine6-PGLA). UUO increased pSTAT3 and subsequently elevated SOCS3 levels in the obstructed kidneys. pSTAT3 levels were further increased in SOCS3(+/-) mice. UUO-induced renal fibrosis was markedly suppressed in SOCS3(+/-) mice, while it was aggravated by pre-treatment with pyridine6-PGLA. Although there were no differences in renal mRNA levels of TGF-ß and collagens between wild and SOCS3(+/-) mice, MMP-2 activity was enhanced in SOCS3(+/-) UUO mice. Activated MMP-2 was completely suppressed by pyridine6-PGLA-pre-treatment. TNF-α one of JAK/STAT activators, increased pSTAT3 levels and subsequently induced MMP-2 activation in proximal tubular cells. These results suggest that JAK/STAT3 signaling may play a role in repair process of renal fibrosis in UUO partly via MMP-2 activation.

SOCS, Inflammation, and Autoimmunity.

Cytokines play essential roles in innate and adaptive immunity. However, excess cytokines or dysregulation of cytokine signaling will cause a variety of diseases, including allergies, autoimmune diseases, inflammation, and cancer. Most cytokines utilize the so-called Janus kinase-signal transducers and activators of transcription pathway. This pathway is negatively regulated by various mechanisms including suppressors of cytokine signaling (SOCS) proteins. SOCS proteins bind to JAK or cytokine receptors, thereby suppressing further signaling events. Especially, suppressor of cytokine signaling-1 (SOCS1) and SOCS3 are strong inhibitors of JAKs, because these two contain kinase inhibitory region at the N-terminus. Studies using conditional knockout mice have shown that SOCS proteins are key physiological as well as pathological regulators of immune homeostasis. Recent studies have also demonstrated that SOCS1 and SOCS3 are important regulators of helper T cell differentiation and functions. This review focuses on the roles of SOCS1 and SOCS3 in T cell mediated inflammatory diseases.

Cardiac-specific deletion of SOCS-3 prevents development of left ventricular remodeling after acute myocardial infarction.

OBJECTIVES: The study investigated the role of myocardial suppressor of cytokine signaling-3 (SOCS3), an intrinsic negative feedback regulator of the janus kinase and signal transducer and activator of transcription (JAK-STAT) signaling pathway, in the development of left ventricular (LV) remodeling after acute myocardial infarction (AMI). BACKGROUND: LV remodeling after AMI results in poor cardiac performance leading to heart failure. Although it has been shown that JAK-STAT-activating cytokines prevent LV remodeling after AMI in animals, little is known about the role of SOCS3 in this process. METHODS: Cardiac-specific SOCS3 knockout mice (SOCS3-CKO) were generated and subjected to AMI induced by permanent ligation of the left anterior descending coronary artery. RESULTS: Although the initial infarct size after coronary occlusion measured by triphenyltetrazolium chloride staining was comparable between SOCS3-CKO and control mice, the infarct size 14 days after AMI was remarkably inhibited in SOCS3-CKO, indicating that progression of LV remodeling after AMI was prevented in SOCS3-CKO hearts. Prompt and marked up-regulations of multiple JAK-STAT-activating cytokines including leukemia inhibitory factor and granulocyte colony-stimulating factor (G-CSF) were observed within the heart following AMI. Cardiac-specific SOCS3 deletion enhanced multiple cardioprotective signaling pathways including STAT3, AKT, and extracellular signal-regulated kinase (ERK)-1/2, while inhibiting myocardial apoptosis and fibrosis as well as augmenting antioxidant expression. CONCLUSIONS: Enhanced activation of cardioprotective signaling pathways by inhibiting myocardial SOCS3 expression prevented LV remodeling after AMI. Our data suggest that myocardial SOCS3 may be a key molecule in the development of LV remodeling after AMI.

SOCS3: A novel therapeutic target for cardioprotection.

The suppressors of cytokine signaling (SOCS) family of proteins are cytokine-inducible inhibitors of Janus kinase (JAK)-signal transducer and activator of the transcription (STAT) signaling pathways. Among the family, SOCS1 and SOCS3 potently suppress cytokine actions by inhibiting JAK kinase activities. The generation of mice lacking individual SOCS genes has been instrumental in defining the role of individual SOCS proteins in specific cytokine pathways in vivo; SOCS1 is an essential negative regulator of interferon-γ (IFNγ) and SOCS3 is an essential negative regulator of leukemia inhibitory factor (LIF). JAK-STAT3 activating cytokines have exhibited cardioprotective roles in the heart. The cardiac-specific deletion of SOCS3 enhances the activation of cardioprotective signaling pathways, inhibits myocardial apoptosis and fibrosis and results in the inhibition of left ventricular remodeling after myocardial infarction (MI). We propose that myocardial SOCS3 is a key determinant of left ventricular remodeling after MI, and SOCS3 may serve as a novel therapeutic target to prevent left ventricular remodeling after MI. In this review, we discuss the signaling pathways mediated by JAK-STAT and SOCS proteins and their roles in the development of myocardial injury under stress (e.g., pressure overload, viral infection and ischemia).

Suppression of SOCS3 in macrophages prevents cancer metastasis by modifying macrophage phase and MCP2/CCL8 induction.

Inflammation has been demonstrated to play important roles in tumorigenesis, tumor progression, and metastasis. STAT3 has been shown to be frequently activated in a variety of human cancer cells and STAT3 signaling promotes the growth and survival of tumor cells. However, the role of STAT3 of myeloid cells associated with tumors is currently unknown. Suppressor of cytokine signaling-3 (SOCS3) has been shown to be a negative regulator of STAT3. In this study, we used macrophage specific SOCS3 conditional knockout (cKO) mice to investigate the effect of the hyperactivation of STAT3 in macrophages on tumor development and metastasis. In a subcutaneous transplantation model of B16F10 melanoma cells, although tumor sizes were not significantly different, SOCS3-cKO mice survived longer than wild-type (WT) mice did. SOCS3-cKO mice exhibited fewer lung and liver metastatic tumor nodules than WT mice when B16F10 was challenged intravenously. SOCS3(-/-) macrophages stimulated with tumor lysates in vitro exhibited prolonged STAT3 phosphorylation and produced less amount of TNFα and IL-6, and higher amount of MCP2/CCL8 than WT macrophages. MCP/CCL8 was induced via STAT3 and exhibited anti-tumor metastatic effect in WT mice. These data suggest that hyperactivation of STAT3 in myeloid cells simultaneously exerted an anti-inflammatory as well as anti-tumor effects. Thus, the targeted inhibition of SOCS3 activity in macrophages may be therapeutic for the suppression of tumor metastasis.

Suppressors of cytokine signaling (SOCS) proteins and JAK/STAT pathways: regulation of T-cell inflammation by SOCS1 and SOCS3.

Various cytokines are involved in the regulation of the immune system and inflammation. Dysregulation of cytokine signaling can cause a variety of diseases, including allergy, autoimmune diseases, inflammation, and cancer. Most cytokines use the so-called janus kinase/signal transducer and activator of transcription pathway, and this pathway is negatively regulated by suppressors of cytokine signaling (SOCS) proteins. SOCS proteins bind to janus kinase and to certain cytokine receptors and signaling molecules, thereby suppressing further signaling events. Studies have shown that SOCS proteins are key physiological regulators of inflammation. Recent studies have also demonstrated that SOCS1 and SOCS3 are important regulators of adaptive immunity.

Mesenchymal stem cell-based prostacyclin synthase gene therapy for pulmonary hypertension rats.

Mesenchymal stem cells (MSCs) are the pluripotent cells, which enter the circulation and home to sites of tissue injury or inflammation. MSCs are highlighted as a potential cell vector for gene therapy. In this study, we investigated whether transplanted allogeneic MSCs preferentially accumulate in the lung in rats with pulmonary hypertension (PH) and if so to determine the efficacy of MSC-based prostacyclin synthase (PCS) gene therapy for PH. PH was induced in Lewis rats by injecting monocrotaline at 7-weeks-old (week 0). MSCs were obtained by culturing bone marrow mononuclear cells. Allogeneic MSCs were intravenously transplanted at week 2 when moderate PH had been established. PH enhanced indium-111-oxine-labeled MSC accumulation in the lungs, but not in other organs, 2.5-times and 6-times, 1 and 14 days after transplantation, respectively. Transplantation of MSCs transduced with PCS (PSC-MSCs), but not with GFP (GFP-MSCs), reduced PH, pulmonary arterial thickening, and RV hypertrophy at week 4. The lung prostacyclin production was impaired in PH rats, which was restored and maintained for long time by PCS-MSCs, but not by GFP-MSCs. The survival rate at week 7 was 100% in PCS-MSC-transplanted PH rats, whereas they were 38 and 44% in PH rats and GFP-MSC-transplanted PH rats, respectively. In conclusion, the gene-engineered MSCs would be a suitable cell vector for gene delivery specifically to the PH lung. The allogeneic PCS-MSC transplantation attenuated PH and cardiovascular remodeling, and improved the prognosis in PH rats. The MSC-based PCS gene therapy may be a promising strategy for PH treatment.

Loss of SOCS3 expression in T cells reveals a regulatory role for interleukin-17 in atherosclerosis.

Atherosclerosis is an inflammatory vascular disease responsible for the first cause of mortality worldwide. Recent studies have clearly highlighted the critical role of the immunoinflammatory balance in the modulation of disease development and progression. However, the immunoregulatory pathways that control atherosclerosis remain largely unknown. We show that loss of suppressor of cytokine signaling (SOCS) 3 in T cells increases both interleukin (IL)-17 and IL-10 production, induces an antiinflammatory macrophage phenotype, and leads to unexpected IL-17-dependent reduction in lesion development and vascular inflammation. In vivo administration of IL-17 reduces endothelial vascular cell adhesion molecule-1 expression and vascular T cell infiltration, and significantly limits atherosclerotic lesion development. In contrast, overexpression of SOCS3 in T cells reduces IL-17 and accelerates atherosclerosis. We also show that in human lesions, increased levels of signal transducer and activator of transcription (STAT) 3 phosphorylation and IL-17 are associated with a stable plaque phenotype. These results identify novel SOCS3-controlled IL-17 regulatory pathways in atherosclerosis and may have important implications for the understanding of the increased susceptibility to vascular inflammation in patients with dominant-negative STAT3 mutations and defective Th17 cell differentiation.

Suppressor of cytokine signaling 1 protects mice against concanavalin A-induced hepatitis by inhibiting apoptosis.

UNLABELLED: Acute liver failure is associated with significant mortality. However, the underlying pathophysiological mechanism is not yet fully understood. Suppressor of cytokine signaling-1 (SOCS1), which is a negative-feedback molecule for cytokine signaling, has been shown to be rapidly induced during liver injury. Here, using liver-specific SOCS1-conditional-knockout mice, we demonstrated that SOCS1 deletion in hepatocytes enhanced concanavalin A (ConA)-induced hepatitis, which has been shown to be dependent on activated T and natural killer T (NKT) cells. Although serum cytokine level and NKT cell activation were similar in wild-type (WT) and SOCS1-deficient mice after ConA treatment, proapoptotic signals, including signal transducers and activators of transcription 1 (STAT1) and Jun-terminal kinase (JNK) activation, were enhanced in SOCS1-deficient livers compared with those in WT livers. SOCS1-deficient hepatocytes had higher expression of Fas antigen and were more sensitive to anti-Fas antibody-induced apoptosis than were WT hepatocytes. Furthermore, SOCS1-deficient hepatocytes were more sensitive to tumor necrosis factor (TNF)-alpha-induced JNK activation and apoptosis. These data indicate that SOCS1 is important to the prevention of hepatocyte apoptosis induced by Fas and TNF-alpha. In contrast, SOCS1 overexpression in the liver by adenoviral gene transfer prevented ConA-induced liver injury. CONCLUSION: These findings indicate that SOCS1 plays important negative roles in fulminant hepatitis and that forced expression of SOCS1 is therapeutic in preventing hepatitis.

Inhibition of progression and stabilization of plaques by postnatal interferon-gamma function blocking in ApoE-knockout mice.

A role of interferon-gamma is suggested in early development of atherosclerosis. However, the role of interferon-gamma in progression and destabilization of advanced atherosclerotic plaques remains unknown. Thus, the aim of this study was to determine whether postnatal inhibition of interferon-gamma signaling could inhibit progression of atherosclerotic plaques and stabilize the lipid- and macrophage-rich advanced plaques. Atherosclerotic plaques were induced in ApoE-knockout (KO) mice by feeding high-fat diet from 8 weeks old (w). Interferon-gamma function was postnatally inhibited by repeated gene transfers of a soluble mutant of interferon-gamma receptors (sIFNgammaR), an interferon-gamma inhibitory protein, into the thigh muscle every 2 weeks. When sIFNgammaR treatment was started at 12 w (atherosclerotic stage), sIFNgammaR not only prevented plaque progression but also stabilized advanced plaques at 16 w: sIFNgammaR decreased accumulations of the lipid and macrophages and increased fibrotic area with more smooth muscle cells. Moreover, sIFNgammaR downregulated expressions of proinflammatory cytokines, chemokines, adhesion molecules, and matrix metalloproteinases but upregulated procollagen type I. sIFNgammaR did not affect serum cholesterol levels. In conclusion, postnatal blocking of interferon-gamma function by sIFNgammaR treatment would be a new strategy to inhibit plaque progression and to stabilize advanced plaques through the antiinflammatory effects.

Platelet P-selectin plays an important role in arterial thrombogenesis by forming large stable platelet-leukocyte aggregates.

OBJECTIVES: We investigated the role of P-selectin in arterial thrombogenesis by forming large stable platelet-leukocyte aggregates. BACKGROUND: Plaque rupture followed by thrombus formation is a fundamental pathophysiology of acute coronary syndromes. Although the adhesive interaction between platelets and leukocytes via P-selectin is known to mediate platelet-rich thrombi, the true function of P-selectin in thrombus formation in vivo is unknown. METHODS: In wild-type (P(+/+)) and P-selectin-deficient (P(-/-)) mice with ferric chloride (FeCl(3))-induced carotid arterial thrombosis model, we measured in vivo platelet P-selectin expression and adenosine diphosphate (ADP)-induced ex vivo platelet aggregation. We also measured ex vivo ADP-induced whole blood aggregations and their size distribution by flow cytometry. RESULTS: Time to thrombotic occlusion was longer in P(-/-) mice than in P(+/+) mice. Spontaneous reflow after total thrombotic occlusion was observed in 8 of 10 P(-/-) mice but not in any P(+/+) mice. ADP-induced ex vivo platelet aggregation was not different between the two groups. However, ADP-induced ex vivo whole blood aggregation was inhibited in P(-/-) mice compared to P(+/+) mice. FeCl(3) application increased in vivo expressions of platelet P-selectin in P(+/+) mice but not in P(-/-) mice. The number of leukocytes within thrombi was less in P(-/-) mice than in P(+/+) mice. In flow cytometric analysis of size distribution of ADP-induced whole blood aggregates, the number of large aggregates was less in P(-/-) mice than in P(+/+) mice. Using platelet and leukocyte fluorescence makers, the large aggregates were confirmed as platelet-leukocyte aggregates. CONCLUSIONS: Platelet P-selectin plays an important role in arterial thrombogenesis by forming large stable platelet-leukocyte aggregates.

Small proline-rich protein 1A is a gp130 pathway- and stress-inducible cardioprotective protein.

The interleukin-6 cytokines, acting via gp130 receptor pathways, play a pivotal role in the reduction of cardiac injury induced by mechanical stress or ischemia and in promoting subsequent adaptive remodeling of the heart. We have now identified the small proline-rich repeat proteins (SPRR) 1A and 2A as downstream targets of gp130 signaling that are strongly induced in cardiomyocytes responding to biomechanical/ischemic stress. Upregulation of SPRR1A and 2A was markedly reduced in the gp130 cardiomyocyte-restricted knockout mice. In cardiomyocytes, MEK1/2 inhibitors prevented SPRR1A upregulation by gp130 cytokines. Furthermore, binding of NF-IL6 (C/EBPbeta) and c-Jun to the SPRR1A promoter was observed after CT-1 stimulation. Histological analysis revealed that SPRR1A induction after mechanical stress of pressure overload was restricted to myocytes surrounding piecemeal necrotic lesions. A similar expression pattern was found in postinfarcted rat hearts. Both in vitro and in vivo ectopic overexpression of SPRR1A protected cardiomyocytes against ischemic injury. Thus, this study identifies SPRR1A as a novel stress-inducible downstream mediator of gp130 cytokines in cardiomyocytes and documents its cardioprotective effect against ischemic stress.