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1.
Addict Biol ; 29(3): e13383, 2024 03.
Article in English | MEDLINE | ID: mdl-38488760

ABSTRACT

Repeated abuse of methamphetamine (METH) can cause dependence, repeated relapse of psychotic symptoms, compulsive drug-seeking behaviour, and various neurological symptoms. These long-term biological changes may be associated with epigenetic mechanisms; however, the association between METH use and epigenetic mechanisms has been poorly investigated. Thus, we performed an epigenome-wide association study of METH dependence using genomic DNA extracted from the blood samples of 24 patients with METH dependence and 24 normal controls. All participants were of Japanese descent. We tested the association between METH dependence and DNA methylation using linear regression analysis. We found epigenome-wide significant associations at four CpG sites, one of which occurred in the CNOT1 gene and another in the PUM1 gene. We especially noted the CNOT1 and PUM1 genes as well as several other genes that indicated some degree of association with METH dependence. Among the relatively enriched Gene Ontology terms, we were interested in terms of mRNA metabolism, respirasome, and excitatory extracellular ligand-gated ion channel activity. Among the relatively enriched Kyoto Encyclopedia of Genes and Genome pathways, we noted pathways of several neurological diseases. Our results indicate that genetic changes akin to those in other psychiatric or neurodegenerative disorders may also occur via epigenetic mechanisms in patients with METH dependence.


Subject(s)
Amphetamine-Related Disorders , Methamphetamine , Humans , Epigenome/genetics , Amphetamine-Related Disorders/genetics , Epigenesis, Genetic/genetics , DNA Methylation , Genome-Wide Association Study , RNA-Binding Proteins/genetics , Transcription Factors/genetics
2.
Psychiatry Res ; 317: 114901, 2022 11.
Article in English | MEDLINE | ID: mdl-36244160

ABSTRACT

Methamphetamine (MA) is used worldwide and causes serious public health and social problems. MA affects the central nervous, cardiac, and immune systems, which causes neuropsychiatric and cardiovascular diseases and infection. Epigenetic changes, including DNA methylation (DNAm), are associated with various clinical phenotypes of MA abuse. DNAm is related to biological aging and health risks; hence, we aimed to assess the changes in biological aging in MA dependence using the DNAm age and DNA methylation-based telomere length (DNAmTL). We used five measures of DNAm age (HorvathAge, HannumAge, SkinBloodAge, PhenoAge, and GrimAge), DNAmTL, and DNAm-based age-predictive factors (plasma proteins and blood cell composition). We compared patients with MA dependence and healthy controls (n = 24 each) using the DNAm profiles obtained from whole-blood samples. Patients with MA dependence showed significant acceleration in PhenoAge and GrimAge, as well as a trend for significant acceleration in DNAmTL. Following adjustment for confounding factors, MA dependence was significantly associated with accelerations in PhenoAge, GrimAge, and DNAmTL, as well as alterations in DNAm-based age-predictive factors (beta-2-microglobulin, granulocytes, and naive cluster of differentiation 4+ T cells). Our results suggested an acceleration of biological aging and specific changes in the DNAm of age- predictive factors in MA dependence.


Subject(s)
Cardiovascular Diseases , Methamphetamine , Humans , Epigenesis, Genetic , DNA Methylation , Methamphetamine/adverse effects
3.
Nihon Ronen Igakkai Zasshi ; 59(2): 200-208, 2022.
Article in Japanese | MEDLINE | ID: mdl-35650053

ABSTRACT

AIMS: The purpose of this study was to objectively quantify the sleep of elderly patients with dementia at home using a device and to investigate the factors associated with its identification. METHODS: Sixteen patients (6 males [37.5%], 84.1±4.7 years old; and 10 patients with mild dementia [62.5%]) and their family caregivers who were using outpatient memory clinics and home-visiting nursing station in Japan were included. Demographic and clinical data of the patients and their family caregivers, subjective perceptions of patients' sleep, family caregivers' Zarit care burden, and whether or not they were aware of patients' sleep problems were determined. Nighttime sleep parameters were collected for one week using a non-wearable actigraph. Sleep parameters were compared with patients' subjective views and family caregivers' observations to investigate factors indicative of sleep disturbance. RESULTS: Nighttime sleep parameters for 1 week (mean) were follows: sleep efficiency, 77.2%±9.3%; asleep time, 442.3±99.9 minutes; sleep latency, 18.2±15.8 minutes; awake time, 105.1±69.7 minutes; and number of times leaving the bed, 4.6±3.8 (maximum of 29/night). A significant positive correlation was found between sleep efficiency and duration of dementia (r=0.53, p=0.046), while no correlation was found with dementia severity or Zarit care burden score. The agreement between the patients' complaints about sleep and sleep efficiency (75%) was 30.7%, and family caregivers' awareness of patients' nighttime awakening and bed-leaving was significantly associated with patients' incontinence (p=0.024) and a greater dementia severity (p=0.027). CONCLUSIONS: Elderly dementia patients experienced sleep disturbance at home, such as nighttime awakening and associated bed-leaving; however, it might be difficult to identify these patients at an early stage based on their own complaints and observations by family caregivers. Identifying sleep problems at an early stage may thus require the use of objective measurement devices.


Subject(s)
Dementia , Sleep Wake Disorders , Aged , Aged, 80 and over , Caregivers , Dementia/complications , Humans , Japan , Male , Sleep , Sleep Wake Disorders/etiology
4.
Diabetes ; 62(1): 223-33, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22933108

ABSTRACT

ACE type 2 (ACE2) functions as a negative regulator of the renin-angiotensin system by cleaving angiotensin II (AII) into angiotensin 1-7 (A1-7). This study assessed the role of endogenous ACE2 in maintaining insulin sensitivity. Twelve-week-old male ACE2 knockout (ACE2KO) mice had normal insulin sensitivities when fed a standard diet. AII infusion or a high-fat, high-sucrose (HFHS) diet impaired glucose tolerance and insulin sensitivity more severely in ACE2KO mice than in their wild-type (WT) littermates. The strain difference in glucose tolerance was not eliminated by an AII receptor type 1 (AT1) blocker but was eradicated by A1-7 or an AT1 blocker combined with the A1-7 inhibitor (A779). The expression of GLUT4 and a transcriptional factor, myocyte enhancer factor (MEF) 2A, was dramatically reduced in the skeletal muscles of the standard diet-fed ACE2KO mice. The expression of GLUT4 and MEF2A was increased by A1-7 in ACE2KO mice and decreased by A779 in WT mice. A1-7 enhanced upregulation of MEF2A and GLUT4 during differentiation of myoblast cells. In conclusion, ACE2 protects against high-calorie diet-induced insulin resistance in mice. This mechanism may involve the transcriptional regulation of GLUT4 via an A1-7-dependent pathway.


Subject(s)
Glucose Transporter Type 4/genetics , Insulin Resistance , Peptidyl-Dipeptidase A/physiology , Angiotensin I/pharmacology , Angiotensin II/pharmacology , Angiotensin-Converting Enzyme 2 , Animals , Diet, High-Fat , Dietary Carbohydrates/administration & dosage , Energy Intake , Glucose/metabolism , Glucose Intolerance , Glucose Transporter Type 4/physiology , Homeostasis , MEF2 Transcription Factors , Mice , Mice, Inbred C57BL , Mice, Knockout , Muscle, Skeletal/metabolism , Myoblasts/metabolism , Myogenic Regulatory Factors/genetics , Peptide Fragments/pharmacology
6.
J Clin Immunol ; 31(2): 167-73, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21063900

ABSTRACT

Adiponectin is an adipocyte-derived cytokine with anti-inflammatory properties. Paradoxically, circulating adiponectin levels are increased in a number of inflammatory diseases. Thus, we sought to define the role of adiponectin deficiency in mouse models of autoimmunity. Adiponectin-deficient mice on a C57BL/6 background do not develop an autoimmune phenotype. Autoimmunity was also not observed in adiponectin-deficient mice generated on the permissive MRL background. However, adiponectin deficiency exacerbated the autoimmune phenotype of MRL-lpr mice. Compared with MRL-lpr mice, MRL-lpr.apn(-/-) mice displayed greater lymphadenopathy and splenomegaly, as well as increased anti-nuclear antibody and anti-dsDNA production. In addition, evaluation of the kidney revealed larger glomerular tuft size, crescent formation, increased IgG and C3 deposits, and mesangial expansion in the MRL-lpr.apn(-/-) mice. The effects of adiponectin deficiency on the autoimmune phenotypes were more pronounced in female versus male mice. These data show that, while adiponectin deficiency is not sufficient to confer autoimmunity, adiponectin acts as a negative modulator of the autoimmune phenotype in a murine model of lupus.


Subject(s)
Adiponectin/deficiency , Lupus Erythematosus, Systemic/immunology , Phenotype , Adiponectin/blood , Adiponectin/genetics , Adiponectin/immunology , Animals , Antibodies, Antinuclear/blood , Autoimmunity/immunology , Disease Models, Animal , Female , Immunomodulation , Kidney/pathology , Lupus Erythematosus, Systemic/genetics , Lymphatic Diseases/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Inbred MRL lpr , Mice, Knockout , Splenomegaly/pathology
7.
Hypertension ; 56(2): 247-52, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20530298

ABSTRACT

Calcium is an essential signaling molecule that controls vascular smooth muscle cell (VSMC) contraction, proliferation, and differentiation. Here, we show that the calcium antagonist nifedipine inhibits VSMC dedifferentiation in vitro and in vivo. Differentiated VSMCs cultured on laminin-coated dishes were transferred to laminin-free dishes to induce dedifferentiation. Induction of dedifferentiation resulted in the upregulation of nonmuscle myosin heavy chain expression, a marker of dedifferentiation, and the downregulation of smooth muscle myosin heavy chain expression, a marker of differentiation. Nifedipine significantly inhibited both the induction of these phenotypic changes and upregulation of Akt signaling in these cells. Administration of nifedipine at a low concentration that did not affect blood pressure could inhibit the increase in nonmuscle myosin heavy chain expression and decrease in smooth muscle myosin heavy chain expression in a rat balloon-injury model. Furthermore, nifedipine suppressed neointimal hyperplasia and upregulation of Akt signaling. However, phospho-Akt expression was not suppressed in the regenerating arterial endothelium of the nifedipine-treated rats. The inhibitory effect of the downregulation of Akt signaling by dominant-negative Akt on the induction of VSMC dedifferentiation in the intima was identical to that of nifedipine. In contrast, upregulation of Akt signaling by transfection of the cells with a constitutively active Akt reversed the nifedipine-induced inhibition of VSMC dedifferentiation. In conclusion, nifedipine inhibits VSMC dedifferentiation by suppressing Akt signaling, thereby preventing neointimal thickening.


Subject(s)
Cell Differentiation/drug effects , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/physiology , Nifedipine/pharmacology , Proto-Oncogene Proteins c-akt/physiology , Adenoviridae/genetics , Adenoviridae/physiology , Animals , Aorta/cytology , Aorta/drug effects , Aorta/physiology , Aorta/virology , Down-Regulation/drug effects , Humans , Male , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/virology , Proto-Oncogene Proteins c-akt/genetics , Rats , Rats, Sprague-Dawley , Tunica Intima/drug effects , Tunica Intima/physiology , Up-Regulation/drug effects , Vasodilator Agents/pharmacology
8.
Lab Invest ; 89(12): 1340-7, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19806081

ABSTRACT

Extracellular matrix (ECM) degradation is performed primarily by matrix metalloproteinases (MMPs). MMPs have recently been shown to regulate synaptic activity in the hippocampus and to affect memory and learning. The tissue inhibitor of metalloproteinase (Timp) is an endogenous factor that controls MMP activity by binding to the catalytic site of MMPs. At present, four Timp isotypes have been reported (Timp-1 through Timp-4) with 35-50% amino-acid sequence homology. Timp-3 is a unique member of Timp proteins in that it is bound to the ECM. In this study, we used the passive avoidance test, active avoidance test, and water maze test to examine the cognitive function in Timp-3 knockout (KO) mice. Habituation was evaluated using the open-field test. The water maze test showed that Timp-3 KO mice exhibit deterioration in cognitive function compared with wild-type (WT) mice. The open-field test showed decreased habituation of Timp-3 KO mice. Immunostaining of brain slices revealed the expression of Timp-3 in the hippocampus. In situ zymography of the hippocampus showed increased gelatinolytic activity in Timp-3 KO mice compared with WT mice. These results present the first evidence of Timp-3 involvement in cognitive function and hippocampal MMP activity in mice. Moreover, our findings suggest a novel therapeutic target to be explored for improvement of cognitive function in humans.


Subject(s)
Avoidance Learning/physiology , Hippocampus/enzymology , Memory/physiology , Tissue Inhibitor of Metalloproteinase-3/deficiency , Animals , Gelatinases/metabolism , Habituation, Psychophysiologic , Male , Mice , Mice, Inbred C57BL , Mice, Knockout
9.
Endocrine ; 35(3): 341-6, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19367378

ABSTRACT

Klotho is a senescence suppressor protein that, when overexpressed, extends the lifespan of mice. Klotho-disrupted mice exhibit atherosclerosis and endothelial dysfunction, which led us to investigate the effect of the Klotho protein on vascular inflammation, particularly adhesion molecule expression. In this study, human umbilical vein endothelial cells (HUVECs) were preincubated with Klotho protein and then exposed to tumor necrosis factor-alpha (TNF-alpha) or vehicle. Reverse transcription-PCR and Western blot analyses revealed that Klotho suppressed TNF-alpha-induced expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). NF-kappaB activation, IkappaB phosphorylation induced by TNF-alpha were also attenuated by Klotho protein administration. The inhibition of eNOS phosphorylation by TNF-alpha was reversed by Klotho. Furthermore, Klotho inhibited TNF-alpha-induced monocyte adhesion to HUVECs and suppressed adhesion molecule expression in an organ culture of the rat aorta. These results suggest that Klotho suppresses TNF-alpha-induced expression of adhesion molecules and NF-kappaB activation. Klotho may have a role in the modulation of endothelial inflammation.


Subject(s)
Cell Adhesion Molecules/genetics , Endothelium, Vascular/drug effects , Glucuronidase/pharmacology , NF-kappa B/antagonists & inhibitors , Tumor Necrosis Factor-alpha/pharmacology , Animals , Aorta/drug effects , Aorta/metabolism , Cell Adhesion/drug effects , Cell Adhesion/genetics , Cell Adhesion Molecules/metabolism , Cells, Cultured , Down-Regulation/drug effects , Endothelium, Vascular/metabolism , Humans , I-kappa B Proteins/metabolism , Inflammation/genetics , Klotho Proteins , Monocytes/drug effects , Monocytes/metabolism , Monocytes/physiology , NF-kappa B/metabolism , Nitric Oxide Synthase Type III/metabolism , Organ Culture Techniques , Phosphorylation/drug effects , Rats
10.
Hypertens Res ; 32(4): 261-4, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19262492

ABSTRACT

A growing body of evidence has shown that Fas-mediated apoptosis is involved in atherosclerosis progression. Recent studies have revealed that a single nucleotide polymorphism (SNP) in the Fas promoter region (-670G/A) influences Fas expression. Here, we investigated whether -670G/A SNP influences the incidence of myocardial infarction (MI) by examining a comparison between MI patients (n=154) and control subjects (n=462) in a Japanese population. The allele frequency in each group was A 53.6%/G 46.4% in the MI patients, and A 43.9%/G 56.1% in the non-MI subjects (chi(2)=8.6; P=0.003). The odds ratio was 2.62 (95% CI: 1.43-4.88). As subjects with the -670AA genotype had a signal transducer and activator of transcription 1 (STAT1)-binding site in the Fas promoter region, STAT-1 activation by interferon-gamma may upregulate Fas expression in human vascular smooth muscle cells (VSMCs) of -670AA genotype subjects as described earlier. The Fas upregulation induces excess apoptosis to VSMCs, which leads to unstable plaque formation in atherosclerotic lesions and then potentially to plaque rupture, which can cause MI. Further investigation of hypertensive subjects revealed that the -670AA genotype does not induce hypertension occurrence, supporting that this difference of MI occurrence between the -670AA genotype and the -670GG genotype may be because of plaque rupture followed by excess apoptosis of VSMCs in the atherosclerotic lesion. We conclude that the Fas promoter gene, SNP (-670G/A), may be a risk factor of MI occurrence.


Subject(s)
Myocardial Infarction/epidemiology , Myocardial Infarction/genetics , Polymorphism, Genetic/genetics , Promoter Regions, Genetic/genetics , fas Receptor/genetics , Aged , Female , Gene Frequency , Genotype , Humans , Hyperlipidemias/epidemiology , Hypertension/epidemiology , Hypertension/genetics , Japan/epidemiology , Male , Middle Aged , Odds Ratio , Reverse Transcriptase Polymerase Chain Reaction , Risk , STAT1 Transcription Factor/genetics
11.
Biochem Biophys Res Commun ; 377(4): 1097-101, 2008 Dec 26.
Article in English | MEDLINE | ID: mdl-18977203

ABSTRACT

Apop-1 is a novel protein identified in cultured atherosclerotic smooth muscle cells of ApoE-deficient mice, and the expression of the Apop-1 protein induces the death of cultured cells. Insulin-like growth factor-1 (IGF-1) is a well-characterized survival factor for VSMC; however, the interaction between Apop-1 and survival factor IGF-1 in the mediation of cell death is poorly understood. In this report, we show that the IGF-1 signaling cascade protects VSMC against Apop-1-induced death. Furthermore, our data indicate that the inhibition of Apop-1-induced death by IGF-1 is mediated by the activation of the PI3K/Akt signaling pathway.


Subject(s)
Apoptosis Regulatory Proteins/metabolism , Apoptosis , Mitochondrial Proteins/metabolism , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Animals , Caspase 9/metabolism , Cells, Cultured , Cytochromes c/metabolism , Enzyme Activation , Insulin-Like Growth Factor I/metabolism , Insulin-Like Growth Factor I/pharmacology , Mice , Mitochondria/drug effects , Mitochondria/enzymology , Muscle, Smooth, Vascular/drug effects , Phosphatidylinositol 3-Kinases/metabolism
12.
J Clin Invest ; 117(2): 375-86, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17256056

ABSTRACT

Obesity and type 2 diabetes are associated with chronic inflammation. Adiponectin is an adipocyte-derived hormone with antidiabetic and antiinflammatory actions. Here, we demonstrate what we believe to be a previously undocumented activity of adiponectin, facilitating the uptake of early apoptotic cells by macrophages, an essential feature of immune system function. Adiponectin-deficient (APN-KO) mice were impaired in their ability to clear apoptotic thymocytes in response to dexamethasone treatment, and these animals displayed a reduced ability to clear early apoptotic cells that were injected into their intraperitoneal cavities. Conversely, adiponectin administration promoted the clearance of apoptotic cells by macrophages in both APN-KO and wild-type mice. Adiponectin overexpression also promoted apoptotic cell clearance and reduced features of autoimmunity in lpr mice whereas adiponectin deficiency in lpr mice led to a further reduction in apoptotic cell clearance, which was accompanied by exacerbated systemic inflammation. Adiponectin was capable of opsonizing apoptotic cells, and phagocytosis of cell corpses was mediated by the binding of adiponectin to calreticulin on the macrophage cell surface. We propose that adiponectin protects the organism from systemic inflammation by promoting the clearance of early apoptotic cells by macrophages through a receptor-dependent pathway involving calreticulin.


Subject(s)
Calreticulin/physiology , Inflammation/prevention & control , Adiponectin/deficiency , Adiponectin/genetics , Adiponectin/pharmacology , Adiponectin/physiology , Animals , Apoptosis/drug effects , Apoptosis/physiology , Base Sequence , Cell Line , DNA Primers/genetics , Humans , Inflammation/etiology , Inflammation/pathology , Inflammation/physiopathology , Jurkat Cells , Mice , Mice, Inbred C57BL , Mice, Inbred MRL lpr , Mice, Knockout , Recombinant Proteins/pharmacology
13.
Curr Atheroscler Rep ; 9(3): 238-43, 2007 Sep.
Article in English | MEDLINE | ID: mdl-18241619

ABSTRACT

Obesity is recognized as a cause of many metabolic and cardiovascular disorders through its ability to promote chronic systemic inflammation. Recent studies have found that adipose tissues secrete numerous cytokines that are referred to as adipokines. Although most adipokines induce inflammation, adiponectin inhibits inflammatory reactions and protects against metabolic and cardiovascular diseases. This review focuses on the anti-inflammatory properties of adiponectin in various experimental systems, especially with respect to cardiovascular diseases.


Subject(s)
Adiponectin/physiology , Liver Diseases/physiopathology , Obesity/physiopathology , Animals , Atherosclerosis/physiopathology , Disease Progression , Heart/physiology , Humans , Inflammation/physiopathology , Macrophages/physiology , Obesity/complications , Receptors, Adiponectin/physiology
14.
Hypertens Res ; 29(4): 217-25, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16778328

ABSTRACT

To find a novel marker for identifying patients at high-risk for endothelial dysfunction among patients with atherosclerosis, we examined the correlation between mRNA levels of Fas ligand (FasL), an apoptosis-inducing factor, in circulating leukocytes and clinical parameters in these patients. FasL mRNA levels of circulating leukocytes were measured with the TaqMan-PCR method. A negative correlation was observed between brachial artery flow-mediated dilatation (%FMD) and FasL mRNA levels of leukocytes in hyperlipidemic but not in non-hyperlipidemic patients. %FMD was more impaired in patients with a high level of FasL mRNA than in those with a low level of FasL mRNA. Interestingly, the improvement of %FMD by treatment with a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (simvastatin) was greater in the group showing a decrease in FasL mRNA than in the group with no such decrease. Additionally, simvastatin suppressed the FasL mRNA expression in leukocytes and decreased plasma oxidized low-density lipoprotein (OxLDL) levels. Furthermore, the supernatant of cultured leukocytes from hyperlipidemic patients induced cell death in Jurkat T cells, which was neutralized by an antibody against FasL. These findings suggest that high FasL mRNA expression in circulating leukocytes may be a marker of high-risk for endothelial dysfunction in hyperlipidemic but not in non-hyperlipidemic patients. This information may provide a novel basis for targeting of statin therapy in patients with vulnerable plaques.


Subject(s)
Endothelium, Vascular/immunology , Hyperlipidemias , Hypolipidemic Agents/administration & dosage , Leukocytes/physiology , Membrane Glycoproteins/genetics , Simvastatin/administration & dosage , Tumor Necrosis Factors/genetics , Aged , Apoptosis/immunology , Atherosclerosis/diagnosis , Atherosclerosis/immunology , Biomarkers/blood , Brachial Artery , Endothelium, Vascular/drug effects , Fas Ligand Protein , Female , Humans , Hyperlipidemias/diagnosis , Hyperlipidemias/drug therapy , Hyperlipidemias/immunology , Jurkat Cells , Leukocytes/cytology , Lipoproteins, LDL/blood , Male , Middle Aged , Predictive Value of Tests , RNA, Messenger/metabolism , Regional Blood Flow , Up-Regulation/immunology , Vasculitis/diagnosis , Vasculitis/immunology
15.
Diabetes ; 55(6): 1660-5, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16731828

ABSTRACT

Vascular ageing is accelerated in patients with diabetes. However, the underlying mechanism remains unclear. Here, we show that high glucose induces activation of apoptosis signal-regulating kinase 1 (ASK1), an apoptosis-inducing signal that mediates endothelial cell senescence induced by hyperglycemia. High glucose induced a time-dependent increase in the levels of ASK1 expression and its activity in human umbilical vein endothelial cells (HUVECs). Incubation of endothelial cells with high glucose increased the proportion of cells expressing senescence-associated beta-galactosidase (SA-beta-gal) activity. However, transfection with an adenoviral construct including a dominant negative form of ASK1 gene significantly inhibited SA-beta-gal activity induced by high glucose. In addition, infection with an adenoviral construct expressing the constitutively active ASK1 gene directly induced an increase in the levels of SA-beta-gal activity. Activation of the ASK1 signal also enhanced plasminogen activator inhibitor-1 (PAI-1) expression in HUVECs. Induction of senescent endothelial cells in aortas and elevation of plasma PAI-1 levels were observed in streptozotocin (STZ) diabetic mice, whereas these changes induced by STZ were attenuated in ASK1-knockout mice. Our results suggest that hyperglycemia accelerates endothelial cell senescence and upregulation of PAI-1 expression through activation of the ASK1 signal. Thus, ASK1 may be a new therapeutic target to prevent vascular ageing and thrombosis in diabetic patients.


Subject(s)
Cellular Senescence/drug effects , Endothelial Cells/drug effects , Glucose/pharmacology , MAP Kinase Kinase Kinase 5/metabolism , Adenoviridae/genetics , Analysis of Variance , Animals , Blotting, Western , Cell Line , Cellular Senescence/genetics , Cellular Senescence/physiology , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/metabolism , Endothelial Cells/cytology , Endothelial Cells/metabolism , Enzyme Activation/drug effects , Enzyme-Linked Immunosorbent Assay , Gene Expression/drug effects , Humans , MAP Kinase Kinase Kinase 5/genetics , Mice , Mice, Knockout , Plasminogen Activator Inhibitor 1/genetics , Plasminogen Activator Inhibitor 1/metabolism , Signal Transduction/drug effects , Streptozocin/toxicity , Time Factors , Transfection
16.
Nat Med ; 11(10): 1096-103, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16155579

ABSTRACT

Obesity-related disorders are associated with the development of ischemic heart disease. Adiponectin is a circulating adipose-derived cytokine that is downregulated in obese individuals and after myocardial infarction. Here, we examine the role of adiponectin in myocardial remodeling in response to acute injury. Ischemia-reperfusion in adiponectin-deficient (APN-KO) mice resulted in increased myocardial infarct size, myocardial apoptosis and tumor necrosis factor (TNF)-alpha expression compared with wild-type mice. Administration of adiponectin diminished infarct size, apoptosis and TNF-alpha production in both APN-KO and wild-type mice. In cultured cardiac cells, adiponectin inhibited apoptosis and TNF-alpha production. Dominant negative AMP-activated protein kinase (AMPK) reversed the inhibitory effects of adiponectin on apoptosis but had no effect on the suppressive effect of adiponectin on TNF-alpha production. Adiponectin induced cyclooxygenase (COX)-2-dependent synthesis of prostaglandin E(2) in cardiac cells, and COX-2 inhibition reversed the inhibitory effects of adiponectin on TNF-alpha production and infarct size. These data suggest that adiponectin protects the heart from ischemia-reperfusion injury through both AMPK- and COX-2-dependent mechanisms.


Subject(s)
Adiponectin/pharmacology , Cyclooxygenase 2/metabolism , Multienzyme Complexes/metabolism , Myocardial Ischemia/prevention & control , Myocardial Reperfusion Injury/prevention & control , Protein Serine-Threonine Kinases/metabolism , AMP-Activated Protein Kinases , Animals , Apoptosis/drug effects , Cells, Cultured , Cyclooxygenase Inhibitors/pharmacology , Cytoprotection/drug effects , Mice , Mice, Inbred C57BL , Mice, Knockout , Muscle Cells/drug effects , Muscle Cells/pathology , Myocardial Ischemia/enzymology , Myocardial Ischemia/pathology , Myocardial Reperfusion Injury/enzymology , Myocardial Reperfusion Injury/pathology , Nitrobenzenes/pharmacology , Rats , Signal Transduction , Sulfonamides/pharmacology , Tumor Necrosis Factor-alpha/biosynthesis
17.
Hypertension ; 43(6): 1208-13, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15117910

ABSTRACT

Hyperhomocysteinemia is an independent risk factor for the development of atherosclerosis. However, the underlying mechanism of endothelial cell injury in hyperhomocysteinemia has not been elucidated. In this study, we examined the effect of homocysteine (Hcy) on Fas-mediated apoptosis in endothelial cells. Hcy-induced upregulation of Fas in endothelial cells (ECs) in a dose-dependent manner. At the same time, Hcy increased intracellular peroxide in ECs. Hcy-induced Fas expression was inhibited by the treatment with catalase. Hcy increased NF-kappaB DNA binding activity, and adenovirus-mediated transfection of a Ikappa-B mutant (Ikappa-B mt) gene inhibited Hcy-induced Fas expression. ECs were sensitive to Fas-mediated apoptosis when exposed to Hcy. Under these condition, Ikappa-B mt protected ECs from Fas-mediated apoptosis. In addition, Hcy inhibited expression of the caspase-8 inhibitor FLICE-inhibitory protein (FLIP). Adenovirus-mediated transfection of constitutively active Akt gene abolished the Hcy-mediated downregulation of FLIP. These data suggest that upregulation of Fas expression and downregulation of FLIP is a mechanism through which Hcy induces EC apoptosis.


Subject(s)
Apoptosis/drug effects , Endothelium, Vascular/drug effects , Homocysteine/toxicity , Intracellular Signaling Peptides and Proteins , fas Receptor/physiology , Animals , Arteriosclerosis/etiology , CASP8 and FADD-Like Apoptosis Regulating Protein , Carrier Proteins/physiology , Endothelial Cells/cytology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Endothelium, Vascular/cytology , Endothelium, Vascular/metabolism , Gene Expression Regulation/drug effects , Humans , I-kappa B Proteins/genetics , I-kappa B Proteins/physiology , Mice , NF-kappa B/physiology , Oxidative Stress , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/physiology , Proto-Oncogene Proteins/antagonists & inhibitors , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/physiology , Proto-Oncogene Proteins c-akt , Recombinant Fusion Proteins/antagonists & inhibitors , Recombinant Fusion Proteins/physiology , Signal Transduction/drug effects , Signal Transduction/physiology , Umbilical Veins/cytology , Up-Regulation/drug effects , fas Receptor/biosynthesis , fas Receptor/genetics
18.
Hypertension ; 43(4): 880-4, 2004 Apr.
Article in English | MEDLINE | ID: mdl-14967838

ABSTRACT

A growing body of evidence has shown that Fas, a death receptor, mediates apoptosis-unrelated biological effects. Here, we report that Fas engagement with Fas ligand induced activation of Akt and upregulation of endothelial nitric oxide synthase expression without induction of apoptosis. In the presence of the phosphatidylinositol 3-kinase inhibitor wortmannin, Fas ligand, however, induced apoptosis instead of upregulation of endothelial nitric oxide synthase expression. In vivo, systolic blood pressure was slightly higher in mutant mice with decreased cell surface Fas expression (lpr mice) compared with wild-type mice. In addition, chronic inhibition of nitric oxide synthesis by N(G)-nitro-l-arginine induced a progressive increase in the levels of blood pressure in wild-type mice, whereas no further increase in the levels of blood pressure was observed in lpr mice. Furthermore, acetylcholine caused a lesser endothelium-dependent relaxation of the strips from lpr mice compared with wild-type mice, although the vasoconstrictor potency of phenylephrine was not different between the two groups. These findings indicate that Fas signaling may have a role in the regulation of endothelial function and blood pressure through modulating endothelial nitric oxide synthase expression in the Akt signal-dependent manner.


Subject(s)
Endothelium, Vascular/enzymology , Membrane Glycoproteins/physiology , Nitric Oxide Synthase/biosynthesis , Protein Serine-Threonine Kinases/physiology , Proto-Oncogene Proteins/physiology , Signal Transduction , fas Receptor/physiology , Acetylcholine/pharmacology , Androstadienes/pharmacology , Animals , Apoptosis/drug effects , Blood Pressure/drug effects , Blood Pressure/physiology , Endothelial Cells/cytology , Endothelial Cells/drug effects , Endothelial Cells/enzymology , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Enzyme Induction/physiology , Enzyme Inhibitors/pharmacology , Fas Ligand Protein , Humans , Insulin/pharmacology , Jurkat Cells/drug effects , Jurkat Cells/metabolism , Male , Mice , Mice, Inbred MRL lpr , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase Type II , Nitric Oxide Synthase Type III , Nitroarginine/pharmacology , Phenylephrine/pharmacology , Phosphoinositide-3 Kinase Inhibitors , Proto-Oncogene Proteins c-akt , Recombinant Proteins/pharmacology , Signal Transduction/drug effects , Signal Transduction/physiology , Umbilical Veins , Vasoconstrictor Agents/pharmacology , Wortmannin
19.
Hypertens Res ; 26(6): 503-8, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12862208

ABSTRACT

Calcium antagonists normalize endothelial dysfunction and improve the clinical outcome in patients with hypertension. However, the mechanism underlying these beneficial effects remains to be elucidated. Here, we show that the calcium antagonist nifedipine upregulates the expression of manganese superoxide dismutase (Mn SOD), an endogenous antioxidant enzyme, in vascular smooth muscle cells (VSMC) via cellular interactions between VSMC and endothelial cells (EC). Nifedipine induced upregulation of Mn SOD activity and expression in VSMC when cocultured with EC but not when cultured individually. NG-Monomethyl-L-arginine (L-NMMA), an inhibitor of nitric oxide (NO) synthesis, inhibited the upregulation of Mn SOD expression induced by nifedipine. Additionally, N-ethyl-2-(1-ethyl-2-hydroxy-2-nitrosohydrazino) ethanamine, a NO donor, reversed this inhibition by L-NMMA, indicating that NO may be involved in the mechanism underlying the nifedipine-induced upregulation of Mn SOD in VSMC. Preincubation of VSMC with Mn SOD antisense oligodeoxyribonucleotides (ODN) blocked the suppressive effects of nifedipine on DNA synthesis in VSMC cocultured with EC, whereas sense ODN had no effect. We conclude that the calcium antagonist nifedipine induces upregulation of Mn SOD expression in VSMC via NO derived from EC. This finding may provide some insight into the mechanism underlying the beneficial effects of calcium antagonists in patients with hypertension.


Subject(s)
Calcium Channel Blockers/pharmacology , Endothelial Cells/physiology , Muscle, Smooth, Vascular/enzymology , Nifedipine/pharmacology , Superoxide Dismutase/biosynthesis , Blotting, Western , Cell Division/drug effects , Cells, Cultured , Coculture Techniques , Endothelial Cells/drug effects , Enzyme Inhibitors/pharmacology , Humans , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/drug effects , Nitric Oxide/physiology , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase Type III , Oligonucleotides, Antisense/pharmacology , Superoxide Dismutase/genetics , Tubulin/biosynthesis , Up-Regulation/drug effects , omega-N-Methylarginine/pharmacology
20.
Hypertension ; 42(3): 342-8, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12874095

ABSTRACT

Dietary supplementation with eicosapentaenoic acid (EPA) improves the prognosis of chronic inflammatory diseases, including atherosclerosis. The mechanism underlying these beneficial effects, however, remains to be elucidated. Here we show that EPA protects endothelial cells from anoikis through upregulation of the cellular FLICE (Fas-associating protein with death domain-like interleukin-1-converting enzyme)-inhibitory protein (cFLIP), an endogenous inhibitor of caspase-8. EPA-induced upregulation of cFLIP expression was partially suppressed by the phosphatidylinositol-3-kinase inhibitor wortmannin. Conversely, treatment with insulinlike growth factor-1 (IGF-1), an activator of phosphatidylinositol-3-kinase/Akt signaling, or infection with an adenoviral construct expressing the constitutively active Akt gene induced upregulation of cFLIP expression. In addition, pretreatment of endothelial cells with either EPA or IGF-1 protected them from anoikis, suggesting that EPA-induced protection against anoikis is partially mediated through activation of Akt. On the other hand, when endothelial cells were already detached, treatment of these cells with EPA but not with IGF-1 protected them against anoikis. Importantly, EPA restored cFLIP expression without activating Akt signaling in detached endothelial cells, whereas IGF-1 had no effect. Additionally, exogenously restored expression of cFLIP by the tetracycline-regulated adenovirus system protected endothelial cells against anoikis. Furthermore, EPA was protective against the loss of endothelium in an organ culture of rat aortas. These findings suggest that EPA protects against endothelial cell anoikis through restoration of cFLIP expression, which might contribute to the mechanism underlying the beneficial effects of EPA in patients with hypertension.


Subject(s)
Anoikis/drug effects , Carrier Proteins/metabolism , Eicosapentaenoic Acid/pharmacology , Endothelium, Vascular/drug effects , Intracellular Signaling Peptides and Proteins , Protein Serine-Threonine Kinases , Aorta/cytology , Aorta/drug effects , Apoptosis/drug effects , Blotting, Western , CASP8 and FADD-Like Apoptosis Regulating Protein , Carrier Proteins/genetics , Cell Survival/drug effects , Cells, Cultured , Endothelium, Vascular/cytology , Endothelium, Vascular/metabolism , Gene Expression , Genetic Vectors/genetics , Humans , Insulin-Like Growth Factor I/pharmacology , Organ Culture Techniques , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-akt , Transfection
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