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1.
Redox Biol ; 30: 101433, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31972507

RESUMO

Studies revealed that the use of renin-angiotensin-aldosterone system antagonism is not associated with a statistically significant reduction in the risk of cardiovascular events in patients with chronic kidney disease (CKD) compared with that in the general population. We tested the hypothesis that indoxyl sulfate (IS) can interfere with the protective effect of valsartan-mediated on endothelial function in vitro and neovascularization in mice underwent subtotal nephrectomy. In human aortic endothelial cells, we first demonstrated that IS impaired the valsartan-mediated phosphorylation of eNOSThr495, nitric oxide production and tube formation via NADPH oxidase (NOX) and protein kinase C (PKC) phosphorylation, but this effect was suppressed by cotreatment with apocynin and calphostin C. In vivo, IS attenuated valsartan-induced angiogenesis in Matrigel plugs in mice. Moreover, in subtotal nephrectomy mice who underwent hindlimb ischemic surgery, valsartan significantly increased the mobilization of endothelial progenitor cells in circulation as well as the reperfusion of blood flow and density of CD31+ capillaries in ischemic limbs. However, IS attenuated the protective effect of valsartan-induced neovascularization and increased the expression of p-PKCαSer657 and p-eNOSThr497 in ischemic limbs. Cotreatment of apocynin and calphostin C reversed the IS impaired-neovascularization and decreased the expression of p-PKCαSer657 and p-eNOSThr497 in ischemic limbs. Our study suggests that the NOX/PKC/eNOS signaling pathway plays a pivotal role in the IS-mediated inhibition of valsartan-conferred beneficial effects on endothelial function in vitro and neovascularization in subtotal nephrectomy mice. We proposed a novel causative role for IS in cardiovascular complications in CKD patients.

2.
J Clin Med ; 8(12)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835897

RESUMO

BACKGROUND: Transient receptor potential ankyrin 1 (TRPA1), a redox-sensing Ca2+-influx channel, serves as a gatekeeper for inflammation. However, the role of TRPA1 in kidney injury remains elusive. METHODS: The retrospective cohort study recruited 46 adult patients with acute kidney injury (AKI) and biopsy-proven acute tubular necrosis (ATN) and followed them up for more than three months. The subjects were divided into high- and low-renal-tubular-TRPA1-expression groups for the comparison of the total recovery of renal function and mortality within three months. The significance of TRPA1 in patient prognosis was evaluated using Kaplan-Meier curves and logistic regression analysis. RESULTS: Of the 46 adult AKI patients with ATN, 12 totally recovered renal function. The expression level of tubular TRPA1 was detected by quantitative analysis of the immunohistochemistry of biopsy specimens from ATN patients. The AKI patients with high tubular TRPA1 expression showed a high incidence of nontotal renal function recovery than those with low tubular TRPA1 expression (OR = 7.14; 95%CI 1.35-37.75; p = 0.02). High TRPA1 expression was independently associated with nontotal recovery of renal function (adjusted OR = 6.86; 95%CI 1.26-37.27; p = 0.03). CONCLUSION: High tubular TRPA1 expression was associated with the nontotal recovery of renal function. Further mechanistic studies are warranted.

3.
J Neuroinflammation ; 16(1): 267, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847859

RESUMO

BACKGROUND: Soluble epoxide hydrolase (sEH) is a bifunctional enzyme with COOH-terminal hydrolase and NH2-terminal lipid phosphatase activities. It is expressed in various cell types in the brain and is involved in the pathogenesis of inflammatory and neurodegenerative diseases. Alzheimer's disease (AD) is a progressive neuroinflammatory and neurodegenerative disease. However, the pathological significance of sEH and underlying molecular mechanism in AD remain unclear. METHODS: To examine the role of sEH in pathogenesis of AD, we used wild-type (WT) mice, soluble epoxide hydrolase deficient (sEH-/-) and two mouse models of AD, including amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic (APP/PS1 Tg) and APP/PS1 Tg/sEH-/- mice. Western blotting analysis and immunohistochemistry assay were performed to evaluate the protein expression. Locomotion, nesting building ability, Y-maze, and Morris water maze tests were conducted to study mouse behavior. The levels of interleukin (IL)-1ß, IL-4, IL-6, and IL-10 and the activities of NF-κB and nuclear factor of activated T cells (NFAT) were measured by commercial assay kits. The quantitative protein level profiling in the brain lysate was analyzed using LC-MS/MS approaches. RESULTS: We demonstrated that the level of sEH was increased in the brain and predominantly appeared in hippocampal astrocytes of APP/PS1 Tg mice. Genetic ablation of sEH in APP/PS1 Tg mice delayed the progression of AD as evidenced by the alleviation in behavior outcomes and Aß plaque deposition. In addition, loss of the function of sEH in APP/PS1 Tg mice increased astrogliosis and the production of astrocyte-derived anti-inflammatory cytokines including IL-1ß, IL-4, and IL-10, as well as the activity of NF-kB and NFAT. Moreover, analysis of gene ontology in the AD brain revealed that important signaling pathways and processes related to AD pathogenesis such as translational regulation, oxidative stress, cytoskeleton reorganization, and small GTPase signal transduction were altered in APP/PS1 Tg/sEH-/- mice compared with APP/PS1 Tg mice. CONCLUSION: Our results suggest that sEH is a crucial regulator in the progression of AD and might be a potential therapeutic target for the treatment of AD.

4.
Clin Sci (Lond) ; 133(23): 2361-2378, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31763675

RESUMO

BACKGROUND: Contrast medium-induced acute kidney injury (CI-AKI) is one of the most common causes of hospital-acquired acute renal failure. However, the pathogenesis of CI-AKI remains unclear. Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide synthase (NOS) inhibitor that is largely metabolised by dimethylarginine dimethylaminohydroxylase (DDAH) in humans. Two isoforms of DDAH exist, namely, DDAH-1 and DDAH-2. In the present study, we examined whether the DDAH-2/ADMA/NOS pathway is involved in the pathogenesis of CI-AKI. METHODS AND RESULTS: Exposure to the contrast medium iopromide led to increase in creatinine and blood urea nitrogen (BUN) levels, accumulation of ADMA, increase in reactive oxygen species (ROS) generation, and an inflammatory response in mice kidney tissue. The injection of adenovirus-harbouring DDAH-2 lowered renal ADMA levels and had a reno-protective effect against contrast-medium injury by decreasing cell apoptosis, ROS, and fibrosis. By contrast, contrast medium-induced renal injury was exacerbated in heterozygous DDAH-2 knockout mice. In the in vitro study, overexpression of DDAH-2 increased the levels of nitrite and intracellular cGMP, while the DDAH-2 knockdown induced the opposite effect. These findings were also observed in the in vivo sample. CONCLUSIONS: Our findings provide the first evidence that the DDAH-2/ADMA/NOS pathway is involved in the pathogenesis of CI-AKI and that the protective effect of DDAH-2 probably arises from the modulation of NOS activity, oxidative stress, and the inflammatory process.

5.
J Cell Mol Med ; 23(10): 6611-6621, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31436906

RESUMO

The contribution of soluble epoxide hydrolase (sEH) to atherosclerosis has been well defined. However, less is understood about the role of sEH and its underlying mechanism in the cholesterol metabolism of macrophages. The expression of sEH protein was increased in atherosclerotic aortas of apolipoprotein E-deficient mice, primarily in macrophage foam cells. Oxidized low-density lipoprotein (oxLDL) increased sEH expression in macrophages. Genetic deletion of sEH (sEH-/- ) in macrophages markedly exacerbated oxLDL-induced lipid accumulation and decreased the expression of ATP-binding cassette transporters-A1 (ABCA1) and apolipoprotein AI-dependent cholesterol efflux following oxLDL treatment. The down-regulation of ABCA1 in sEH-/- macrophages was due to an increase in the turnover rate of ABCA1 protein but not in mRNA transcription. Inhibition of phosphatase activity, but not hydrolase activity, of sEH decreased ABCA1 expression and cholesterol efflux following oxLDL challenge, which resulted in increased cholesterol accumulation. Additionally, oxLDL increased the phosphatase activity, promoted the sEH-ABCA1 complex formation and decreased the phosphorylated level of ABCA1 at threonine residues. Overexpression of phosphatase domain of sEH abrogated the oxLDL-induced ABCA1 phosphorylation and further increased ABCA1 expression and cholesterol efflux, leading to the attenuation of oxLDL-induced cholesterol accumulation. Our findings suggest that the phosphatase domain of sEH plays a crucial role in the cholesterol metabolism of macrophages.

6.
Free Radic Biol Med ; 143: 354-365, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31437479

RESUMO

BACKGROUND: Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide synthase inhibitor and has been proposed to be an independent risk factor for cardiovascular diseases. However, little is known about its role in the regulation of lipid metabolism. In this study, we investigated the effect of ADMA on cholesterol metabolism and its underlying molecular mechanism. METHODS: Oxidized low-density lipoprotein (oxLDL)-induced macrophage foam cells were used as an in vitro model. Apolipoprotein E-deficient (apoE-/-) hyperlipidemic mice were used as an in vivo model. Western blot analysis was used to evaluate protein expression. Luciferase reporter assays were used to assess the activity of promoters and transcription factors. Conventional assay kits were used to measure the levels of ADMA, cholesterol, triglycerides, and cytokines. RESULTS: Treatment with oxLDL decreased the protein expression of dimethylarginine dimethylaminohydrolase-2 (DDAH-2) but not DDAH-1. Incubation with ADMA markedly increased oxLDL-induced lipid accumulation in macrophages. ADMA impaired cholesterol efflux following oxLDL challenge and downregulated the expression of ATP-binding cassette transporter A1 (ABCA1) and ABCG1 by interfering with liver X receptor α (LXRα) expression and activity. Additionally, this inhibitory effect of ADMA on cholesterol metabolism was mediated through the activation of the NADPH oxidase/reactive oxygen species pathway. In vivo experiments revealed that chronic administration of ADMA for 4 weeks exacerbated systemic inflammation, decreased the aortic protein levels of ABCA1 and ABCG1, and impaired the capacity of reverse cholesterol transport, ultimately, leading to the progression of atherosclerosis in apoE-/- mice. CONCLUSION: Our findings suggest that the ADMA/DDAH-2 axis plays a crucial role in regulating cholesterol metabolism in macrophage foam cells and atherosclerotic progression.

7.
Acta Physiol (Oxf) ; 225(3): e13209, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30347516

RESUMO

AIM: CCN family member 1 (CCN1) is an extracellular matrix cytokine and appears in atherosclerotic lesions. However, we have no evidence to support the role of CCN1 in regulating cholesterol metabolism and atherosclerosis. METHODS: Apolipoprotein E-deficient (apoE-/- ) mice were used as in vivo model. Oxidized low-density lipoprotein (oxLDL)-induced macrophage-foam cells were used as in vitro model. RT-PCR and western blot analysis were used for evaluating gene and protein expression, respectively. Conventional assay kits were used for assessing the levels of cholesterol, triglycerides, and cytokines. RESULTS: We show predominant expression of CCN1 in foamy macrophages in atherosclerotic aortas of apoE-/- mice. In apoE-/- mice, CCN1 treatment worsened hyperlipidaemia, systemic inflammation, and the progression of atherosclerosis. In addition, CCN1 decreased the capacity of reverse cholesterol transport and downregulated the protein expression of ATP-binding cassette transporter A1 (ABCA1) and ABCG1 in atherosclerotic aortas. Notably, CCN1 decreased the protein expression of cholesterol clearance-related proteins, including ABCG5, ABCG8, liver X receptor α (LXRα), cholesterol 7α-hydrolase and LDL receptor in liver, and exacerbated hepatic lipid accumulation. In macrophages, treatment with oxLDL increased CCN1 expression. Inhibition of CCN1 activity by neutralizing antibody or small interfering RNA attenuated the oxLDL-induced lipid accumulation. In contrast, cotreatment with CCN1 or overexpression of CCN1 augmented oxLDL-induced lipid accumulation by impairing apolipoprotein AI- and high-density lipoprotein-dependent cholesterol efflux, which was attributed to downregulation of LXRα-dependent expression of ABCA1 and ABCG1. CONCLUSION: Our findings suggest that CCN1 plays a pivotal role in regulating cholesterol metabolism and the development of atherosclerosis.

8.
Mol Neurobiol ; 56(4): 2495-2507, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30033504

RESUMO

Soluble epoxide hydrolase (sEH), an enzyme with COOH-terminal hydrolase and NH2-terminal lipid phosphatase activities, is expressed in regions of the brain such as the cortex, white matter, hippocampus, substantia nigra, and striatum. sEH is involved in the regulation of cerebrovascular and neuronal function upon pathological insults. However, the physiological significance of sEH and its underlying mechanism in modulating brain function are not fully understood. In this study, we investigated the role of sEH in anxiety and potential underlying mechanisms in mice. Western blot for protein phosphorylation and expression was performed. Immunohistochemical analyses and Nissl and Golgi staining were performed for histological examination. Mouse behaviors were evaluated by open field activity, elevated plus maze, classical fear conditioning, social preference test, and Morris water maze. Our results demonstrated that the expression of sEH was upregulated during postnatal development in wild-type (WT) mice. Genetic deletion of sEH (sEH-/-) in mice resulted in anxiety-like behavior and disrupted social preference. Increased olfactory bulb (OB) size and altered integrity of neurites were observed in sEH-/- mice. In addition, ablation of sEH in mice decreased protein expression of tyrosine hydroxylase and reduced dopamine production in the brain. Moreover, the level of phosphorylated calmodulin kinase II (CaMKII) and glycogen synthase kinase 3 α/ß (GSK3α/ß) was higher in sEH-/- mice than in WT mice. Collectively, these findings suggest that sEH is a key player in neurite outgrowth of neurons, OB development in the brain, and the development of anxiety-like behavior, by regulating the CaMKII-GSK3α/ß signaling pathway.


Assuntos
Ansiedade/enzimologia , Comportamento Animal , Epóxido Hidrolases/genética , Deleção de Genes , Tonsila do Cerebelo/enzimologia , Tonsila do Cerebelo/patologia , Animais , Ansiedade/patologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Dopamina/metabolismo , Medo , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/enzimologia , Memória , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuritos/metabolismo , Bulbo Olfatório/anormalidades , Bulbo Olfatório/patologia , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Tirosina 3-Mono-Oxigenase/metabolismo , Substância Branca/patologia
9.
Cell Physiol Biochem ; 50(4): 1216-1229, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30355932

RESUMO

BACKGROUND/AIMS: Olanzapine, an atypical antipsychotic drug, has therapeutic effects for schizophrenia. However, clinical reports indicate that patients taking atypical antipsychotic drugs are at high risk of metabolic syndrome with unclear mechanisms. We investigated the effect of olanzapine on atherosclerosis and the mechanisms in apolipoprotein E-null (apoE-/-) mice. METHODS: ApoE-/- mice were used as in vivo models. Western blot analysis was used to evaluate protein expression. Conventional assay kits were applied to assess the levels of cholesterol, triglycerides, free cholesterol, cholesteryl ester, fatty acids, glycerol, and cytokines. RESULTS: Daily treatment with olanzapine (3 mg/kg body weight) for four weeks increased mean arterial blood pressure and the whitening of brown adipose tissue in mice. In addition, olanzapine impaired aortic cholesterol homeostasis and exacerbated hyperlipidemia and aortic inflammation, which accelerated atherosclerosis in mice. Moreover, lipid accumulation in liver, particularly total cholesterol, free cholesterol, fatty acids, and glycerol, was increased with olanzapine treatment in apoE-/- mice by upregulating the expression of de novo lipid synthesis-related proteins and downregulating that of cholesterol clearance- or very low-density lipoprotein secretion-related proteins. CONCLUSION: Olanzapine may exacerbate atherosclerosis by deregulating hepatic lipid metabolism and worsening hyperlipidemia and aortic inflammation.


Assuntos
Antipsicóticos/farmacologia , Aorta/metabolismo , Aterosclerose/patologia , Benzodiazepinas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Tecido Adiposo Branco/patologia , Animais , Aorta/efeitos dos fármacos , Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Aterosclerose/veterinária , Pressão Sanguínea/efeitos dos fármacos , Colesterol/análise , Colesterol/sangue , Ácidos Graxos/análise , Hiperlipidemias/metabolismo , Hiperlipidemias/patologia , Hiperlipidemias/veterinária , Inflamação , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Knockout , Olanzapina , Triglicerídeos/sangue
10.
Front Physiol ; 9: 1817, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30618827

RESUMO

In smokers with chronic obstructive pulmonary disease, more severe lung inflammation is associated with menthol cigarette smoking compared to non-menthol cigarette smoking. However, the mechanisms remain unclear. Menthol is an activator of transient receptor potential melastatin-8 (TRPM8), which is also sensitive to reactive oxygen species (ROS). Our recent in vitro study demonstrated that the extracts of menthol cigarette smoke (M-CS) can induce greater ROS-sensitive, TRPM8-mediated, mitogen-activated protein kinase (MAPK)-dependent inflammatory responses in lung epithelial cells than the extracts of non-menthol cigarette smoke (Non-M-CS) can. In this study, we tested the hypothesis that M-CS can induce more severe lung inflammation than Non-M-CS can via the additional action of menthol in M-CS on epithelial and lung TRPM8 in mice. Compared with Non-M-CS exposure, subchronic M-CS exposure for 7 days up-regulated the epithelial and lung expression of TRPM8, induced more vigorous activation of epithelial and lung MAPKs, and caused more severe lung inflammation. The MAPK activation was evidenced by the increased expression of phosphor-extracellular signal-regulated and phosphor-c-Jun N-terminal kinases. The lung inflammation was evidenced by pathohistological findings and increases in several inflammatory indices. Moreover, treatment with a TRPM8 antagonist (N-(3-aminopropyl)-2-{[(3-methylphenyl)methyl]oxy}-N-(2-thienylmethyl)benzamide; AMTB) greatly suppressed the MAPK activation and lung inflammation induced by Non-M-CS and M-CS, and the residual responses to these two types of CS did not differ. Conversely, the levels of biomarkers of acute CS exposure (20 min), including carboxyhemoglobin and cotinine (a nicotine metabolite) in blood plasma, and superoxide and hydrogen peroxide (two major types of ROS) in bronchoalveolar lavage fluid, did not show significant differences in the mice with Non-M-CS and M-CS exposure. We concluded that M-CS could induce greater TRPM8-mediated activation of MAPKs and lung inflammation than Non-M-CS could in mice with subchronic exposure. The augmented inflammatory effects of M-CS are unlikely due to a larger total amount of CS inhaled, but may be caused by an additional stimulation of epithelial and lung TRPM8 by menthol in M-CS. A common stimulant (presumably ROS) generated by both CS types may also stimulate TRPM8, activate MAPKs, and induce lung inflammation because treatment with AMTB could reduce these responses to Non-M-CS.

11.
PLoS One ; 12(12): e0188995, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29206850

RESUMO

BACKGROUND: The pathophysiology of cardiac syndrome X is multifactorial and endothelial dysfunction has been implicated as important contributing factor. Asymmetric dimethylarginine (ADMA), characterized as a circulating endogenous inhibitor of nitric oxide synthase, may have been implicated as an important contributing factor for the development of endothelial dysfunction. In this study, we aim to assess the predictive power of ADMA for long-term prognosis in patients with cardiac syndrome X. METHODS AND RESULTS: We enrolled 239 consecutive patients with cardiac syndrome X diagnosed by coronary angiography. The mean age was 58.7±10.1 years. The patients were grouped into tertiles according to the plasma ADMA levels: <0.38 µmol/l (tertile I), 0.38-0.44 µmol/l (tertile II), and >0.44 µmol/l (tertile III). All patients were followed up for a mean period of 6.5±1.5 years (median: 6.3 years, inter-quartile range: 5.7-8.0 years). During the follow-up period, major adverse events (MAE) were observed in 15 patients (6.3%), including 13 deaths. The plasma ADMA levels in patients who developed MAE were significantly higher than those who did not (0.48±0.06 µmol/l vs. 0.42±0.08 µmol/l, p = 0.005). In multivariate Cox regression analysis adjusted for age, eGFR and LVEF, ADMA tertile I and II were identify to be associated with a significantly lower risk of MAE compared to ADMA tertile III (p = 0.017). By considering the plasma ADMA level as a continuous variable, the plasma ADMA level remained a significant independent predictor for outcomes of MAE, and the relative risk of MACE increased by 50% when plasma ADMA level increased by 1 SD of value (p = 0.018). CONCLUSIONS: In patients with cardiac syndrome X, elevated plasma ADMA levels appeared to be an independent predictor of long-term adverse clinical outcomes.


Assuntos
Arginina/análogos & derivados , Síndrome Metabólica/sangue , Idoso , Arginina/sangue , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Masculino , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Prognóstico
13.
Front Physiol ; 8: 263, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28496415

RESUMO

Clinical studies suggest that smokers with chronic obstructive pulmonary disease who use menthol cigarettes may display more severe lung inflammation than those who smoke non-menthol cigarette. However, the mechanisms for this difference remain unclear. Menthol is a ligand of transient receptor potential melastatin-8 (TRPM8), a Ca2+-permeant channel sensitive to reactive oxygen species (ROS). We previously reported that exposure of human bronchial epithelial cells (HBECs) to non-menthol cigarette smoke extract (Non-M-CSE) triggers a cascade of inflammatory signaling leading to IL-8 induction. In this study, we used this in vitro model to compare the inflammatory effects of menthol cigarette smoke extract (M-CSE) and Non-M-CSE and delineate the mechanisms underlying the differences in their impacts. Compared with Non-M-CSE, M-CSE initially increased a similar level of extracellular ROS, suggesting the equivalent oxidant potency. However, M-CSE subsequently produced more remarkable elevations in intracellular Ca2+, activation of the mitogen-activated protein kinases (MAPKs)/nuclear factor-κB (NF-κB) signaling, and IL-8 induction. The extracellular ROS responses to both CSE types were totally inhibited by N-acetyl-cysteine (NAC; a ROS scavenger). The intracellular Ca2+ responses to both CSE types were also totally prevented by NAC, AMTB (a TRPM8 antagonist), or EGTA (an extracellular Ca2+ chelator). The activation of the MAPK/NF-κB signaling and induction of IL-8 to both CSE types were suppressed to similar levels by NAC, AMTB, or EGTA. These results suggest that, in addition to ROS generated by both CSE types, the menthol in M-CSE may act as another stimulus to further activate TRPM8 and induce the observed responses. We also found that menthol combined with Non-M-CSE induced greater responses of intracellular Ca2+ and IL-8 compared with Non-M-CSE alone. Moreover, we confirmed the essential role of TRPM8 in these responses to Non-M-CSE or M-CSE and the difference in these responses between the both CSE types using HBECs with TRPM8 knockdown and TRPM8 knockout, and using HEK293 cells transfected with hTRPM8. Thus, compared with exposure to Non-M-CSE, exposure to M-CSE induced greater TRPM8-mediated inflammatory responses in HBECs. These augmented effects may be due to a double-hit on lung epithelial TRPM8 by ROS generated from CSE and the menthol in M-CSE.

14.
Front Physiol ; 8: 193, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28408888

RESUMO

Pulmonary fibrosis is a severe and progressive disease that is characterized by an abnormal deposition of extracellular matrix, such as collagens. The pathogenesis of this disease may be initiated by oxidative damage of lung epithelial cells by fibrogenic stimuli, leading to lung inflammation, which in turn promotes various lung fibrotic responses. The profibrogenic effect of transforming growth factor-ß1 (TGF-ß1) on lung fibroblasts is crucial for the pathogenesis of this disease. Paeonol, the main phenolic compound present in the Chinese herb Paeonia suffruticosa, has antioxidant and anti-inflammatory properties. However, whether paeonol has therapeutic effects against pulmonary fibrosis remains unclear. Using a murine model, we showed that 21 days after the insult, intratracheal bleomycin caused pulmonary inflammation and fibrosis, as evidenced by lung histopathological manifestations and increase in various indices. The inflammatory indices included an increase in total cell count, differential cell count, and total protein concentration in bronchoalveolar lavage fluid. The fibrotic indices included an increase in lung levels of TGF-ß1, total collagen, type 1α1 collagen (COL1A1), and α-smooth muscle actin (α-SMA; a marker of myofibroblasts). Bleomycin also was found to cause an increase in oxidative stress as reflected by increased levels of malondialdehyde and 4-hydroxynonenal in the lungs. Importantly, all these pathophysiological events were suppressed by daily treatment with paeonol. Using human lung fibroblasts, we further demonstrated that exposure of human lung fibroblasts to TGF-ß1 increased productions of α-SMA and COL1A1, both of which were inhibited by inhibitors of Jun N-terminal kinase (JNK), p38, and Smad3. JNK and p38 are two subfamily members of mitogen-activated protein kinases (MAPKs), whereas Smad3 is a transcription factor. TGF-ß1 exposure also increased the phosphorylation of JNK, p38, and Smad3 prior to the induction of α-SMA and COL1A1. Notably, all these TGF-ß1-induced cellular events were suppressed by paeonol treatment. Our findings suggest that paeonol has antioxidant, anti-inflammatory, and anti-fibrotic functions against bleomycin-induced pulmonary fibrosis in mice. The beneficial effect of paeonol may be, at least in part, mediated through the inhibition of the MAPKs/Smad3 signaling.

15.
Mol Neurobiol ; 54(5): 3606-3617, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27194300

RESUMO

The transient receptor potential ankyrin 1 (TRPA1) channel is a non-selective cation channel that helps regulate inflammatory pain sensation and nociception and the development of inflammatory diseases. However, the potential role of the TRPA1 channel and the underlying mechanism in brain functions are not fully resolved. In this study, we demonstrated that genetic deletion of the TRPA1 channel in mice or pharmacological inhibition of its activity increased neurite outgrowth. In vivo study in mice provided evidence of the TRPA1 channel as a negative regulator in hippocampal functions; functional ablation of the TRPA1 channel in mice enhanced hippocampal functions, as evidenced by less anxiety-like behavior, and enhanced fear-related or spatial learning and memory, and novel location recognition as well as social interactions. However, the TRPA1 channel appears to be a prerequisite for motor function; functional loss of the TRPA1 channel in mice led to axonal bundle fragmentation, downregulation of myelin basic protein, and decreased mature oligodendrocyte population in the brain, for impaired motor function. The TRPA1 channel may play a crucial role in neuronal development and oligodendrocyte maturation and be a potential regulator in emotion, cognition, learning and memory, and social behavior.


Assuntos
Cognição , Emoções , Memória , Comportamento Social , Canal de Cátion TRPA1/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Ansiedade/metabolismo , Axônios/efeitos dos fármacos , Axônios/metabolismo , Comportamento Animal , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Cognição/efeitos dos fármacos , Emoções/efeitos dos fármacos , Medo , Deleção de Genes , Hipocampo/metabolismo , Masculino , Memória/efeitos dos fármacos , Camundongos , Atividade Motora/efeitos dos fármacos , Bainha de Mielina/metabolismo , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Canal de Cátion TRPA1/deficiência , Tretinoína/farmacologia
16.
J Biomed Sci ; 23(1): 69, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27716281

RESUMO

BACKGROUND: Glycine N-methyltransferase (GNMT) is abundantly expressed in the normal liver but is down-regulated in liver cancer tissues. GNMT knockout (Gnmt-/-) mice can spontaneously develop chronic hepatitis, fatty liver, and liver cancer. We previously demonstrated that hepatic GNMT is decreased in high-fat-diet-induced type 2 diabetes mellitus, but its contribution to metabolic syndrome is unclear. Here we show that GNMT modulates key aspects of metabolic syndrome in mice. METHODS: Eleven-week-old Gnmt-/- and wild-type (WT) mice with a C57BL/6 genetic background were used in this study. The metabolic defects of GNMT deficiency were measured by glucose and insulin tolerance tests, lipid homeostasis, gluconeogenesis, and insulin signaling. RESULTS: Gnmt-/- mice, especially females, exhibited glucose intolerance and insulin resistance. However, their body fat and lean mass, food and water intakes, and energy expenditure did not differ from those of WT mice. In addition, glucose-stimulated insulin secretion and insulin-stimulated glucagon secretion were normal in the serum and pancreatic islets of Gnmt-/- mice. Importantly, we found that GNMT deficiency increased lipogenesis and triglycerides in the liver. The elevated triglycerides disrupted the ability of insulin to induce Akt and S6 ribosomal protein phosphorylation, and then triggered insulin resistance and gluconeogenesis in female Gnmt-/- mice. CONCLUSIONS: Our data indicate that hepatic GNMT regulates lipid and glucose homeostasis, and provide insight into the development of insulin resistance through modulating the PI3K/Akt pathway.


Assuntos
Gluconeogênese , Glicina N-Metiltransferase/deficiência , Glicina N-Metiltransferase/genética , Insulina/metabolismo , Fígado/enzimologia , Síndrome Metabólica/genética , Transdução de Sinais , Animais , Feminino , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
17.
Atherosclerosis ; 254: 161-166, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27744140

RESUMO

BACKGROUND AND AIMS: Decreased nitric oxide (NO) bioavailability and increased oxidative stress may be involved in the pathogenesis of contrast-induced acute kidney injury (CI-AKI). The relationship between asymmetric dimethylarginine (ADMA), an endogenous NO synthase inhibitor, and CI-AKI is unknown. METHODS: We measured plasma ADMA levels in 664 consecutive subjects undergoing cardiac catheterization. Mehran score for predicting the risk of CI-AKI was calculated. RESULTS: After cardiac catheterization, 78 (11.7%) patients experienced CI-AKI (defined as increase of serum creatinine levels of ≥0.3 mg/dl or a 25% increase from baseline value at 48 h after the procedure). The plasma ADMA levels of patients with CI-AKI were significantly higher than those of patients without CI-AKI (0.50 ± 0.09 µmol/l versus 0.46 ± 0.10 µmol/l, p < 0.001). The c-statistics of plasma ADMA level and Mehran score for the occurrence of CI-AKI were 0.639 (95% CI: 0.601-0.676, p < 0.001) and 0.615 (95% CI: 0.577-0.652, p = 0.001), respectively. By using a cutpoint of plasma ADMA level of 0.42 µmol/l, the analysis would yield 85.9% sensitivity, 37.0% specificity. Adding the plasma ADMA level to the Mehran score system marginally increases the c-statistic from 0.615 to 0.643 (p = 0.03). Furthermore, in patients developing CI-AKI, those with plasma ADMA levels >0.42 µmol/l (14 events in 52 patients) tended to have a higher 1-year major adverse event rate than those with plasma ADMA level ≤0.42 µmol/l (2 events in 26 patients) (p = 0.055). CONCLUSIONS: In patients undergoing cardiac catheterization, ADMA might be a novel risk factor of CI-AKI.


Assuntos
Lesão Renal Aguda/diagnóstico , Lesão Renal Aguda/etiologia , Arginina/análogos & derivados , Cateterismo Cardíaco , Meios de Contraste/efeitos adversos , Idoso , Arginina/sangue , Meios de Contraste/química , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/química , Estudos Prospectivos , Curva ROC , Fatores de Risco
18.
Int J Mol Sci ; 17(7)2016 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-27420058

RESUMO

In chronic liver diseases, regardless of their etiology, the development of fibrosis is the first step toward the progression to cirrhosis, portal hypertension, and hepatocellular carcinoma. Hepatic stellate cells (HSCs) are the main profibrogenic cells that promote the pathogenesis of liver fibrosis, and so it is important to identify the molecules that regulate HSCs activation and liver fibrosis. Niemann-Pick type C2 (NPC2) protein plays an important role in the regulation of intracellular cholesterol homeostasis by directly binding with free cholesterol. However, the roles of NPC2 in HSCs activation and liver fibrosis have not been explored in detail. Since a high-cholesterol diet exacerbates liver fibrosis progression in both rodents and humans, we propose that the expression of NPC2 affects free cholesterol metabolism and regulates HSCs activation. In this study, we found that NPC2 is decreased in both thioacetamide- and carbon tetrachloride-induced liver fibrosis tissues. In addition, NPC2 is expressed in quiescent HSCs, but its activation status is down-regulated. Knockdown of NPC2 in HSC-T6 cells resulted in marked increases in transforming growth factor-ß1 (TGF-ß1)-induced collagen type 1 α1 (Col1a1), α-smooth muscle actin (α-SMA) expression, and Smad2 phosphorylation. In contrast, NPC2 overexpression decreased TGF-ß1-induced HSCs activation. We further demonstrated that NPC2 deficiency significantly increased the accumulation of free cholesterol in HSCs, increasing Col1a1 and α-SMA expression and activating Smad2, and leading to sensitization of HSCs to TGF-ß1 activation. In contrast, overexpression of NPC2 decreased U18666A-induced free cholesterol accumulation and inhibited the subsequent HSCs activation. In conclusion, our study has demonstrated that NPC2 plays an important role in HSCs activation by regulating the accumulation of free cholesterol. NPC2 overexpression may thus represent a new treatment strategy for liver fibrosis.


Assuntos
Proteínas de Transporte/metabolismo , Colesterol/metabolismo , Glicoproteínas/metabolismo , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/metabolismo , Animais , Western Blotting , Tetracloreto de Carbono/toxicidade , Modelos Animais de Doenças , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Humanos , Técnicas Imunoenzimáticas , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , Tioacetamida/toxicidade , Fator de Crescimento Transformador beta1/farmacologia
19.
Int J Biol Sci ; 12(7): 812-23, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27313495

RESUMO

Transient receptor potential ankyrin 1 channel (TRPA1) plays an important role in the pathogenesis of inflammatory diseases, yet its role and the underlying mechanism in atherosclerosis remain unclear. We aimed to investigate the role of TRPA1 in atherosclerosis and foam-cell formation in vivo in mice and in vitro in mouse macrophages. Histopathology was examined by hematoxylin and eosin staining, levels of cytokines and lipid profile were evaluated by assay kits, and protein expression was determined by western blot analysis. TRPA1 expression was increased in macrophage foam cells in atherosclerotic aortas of apolipoprotein E-deficient (apoE(-/-)) mice. Atherosclerotic lesions, hyperlipidemia and systemic inflammation were worsened with chronic administration of the TRPA1 channel antagonist HC030031 or genetic ablation of TRPA1 (TRPA1(-/-)) in apoE(-/-) mice. Treatment with allyl isothiocyanate (AITC, a TRPA1 agonist) retarded the progression of atherosclerosis in apoE(-/-) mice but not apoE(-/-)TRPA1(-/-) mice. Mouse macrophages showed oxidized low-density lipoprotein (oxLDL) activated TRPA1 channels. OxLDL-induced lipid accumulation of macrophages was exacerbated by HC030031 or loss of function of TRPA1. Inhibition of TRPA1 activity did not alter oxLDL internalization but impaired cholesterol efflux by downregulating the ATP-binding cassette transporters. Furthermore, tumor necrosis factor-α-induced inflammatory response was attenuated in AITC-activated macrophages. TRPA1 may be a pivotal regulator in the pathogenesis of atherosclerosis and cholesterol metabolism of macrophage foam cells.


Assuntos
Aterosclerose/metabolismo , Células Espumosas/citologia , Células Espumosas/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Canais de Receptores Transientes de Potencial/metabolismo , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/genética , Western Blotting , Colesterol/metabolismo , Células Espumosas/efeitos dos fármacos , Imuno-Histoquímica , Isotiocianatos/uso terapêutico , Lipoproteínas LDL/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/farmacologia , Canal de Cátion TRPA1 , Canais de Receptores Transientes de Potencial/antagonistas & inibidores
20.
PLoS One ; 11(5): e0154672, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27139226

RESUMO

Metabolic syndrome (MetS) is a complicated health problem that encompasses a variety of metabolic disorders. In this study, we analyzed the relationship between the major biochemical parameters associated with MetS and circulating levels of microRNA (miR)-33, miR-103, and miR-155. We found that miRNA-33 levels were positively correlated with levels of fasting blood glucose, glycosylated hemoglobin A1c, total cholesterol, LDL-cholesterol, and triacylglycerol, but negatively correlated with HDL-cholesterol levels. In the cellular study, miR-33 levels were increased in macrophages treated with high glucose and cholesterol-lowering drugs atorvastatin and pitavastatin. miR-33 has been reported to play an essential role in cholesterol homeostasis through ATP-binding cassette transporter A1 (ABCA1) regulation and reverse cholesterol transport. However, the molecular mechanism underlying the linkage between miR-33 and statin treatment remains unclear. In the present study, we investigated whether atorvastatin and pitavastatin exert their functions through the modulation of miR-33 and ABCA1-mediated cholesterol efflux from macrophages. The results showed that treatment of the statins up-regulated miR-33 expression, but down-regulated ABCA1 mRNA levels in RAW264.7 cells and bone marrow-derived macrophages. Statin-mediated ABCA1 regulation occurs at the post-transcriptional level through targeting of the 3'-UTR of the ABCA1 transcript by miR-33. Additionally, we found significant down-regulation of ABCA1 protein expression in macrophages treated with statins. Finally, we showed that high glucose and statin treatment significantly suppressed cholesterol efflux from macrophages. These findings have highlighted the complexity of statins, which may exert detrimental effects on metabolic abnormalities through regulation of miR-33 target genes.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/genética , Colesterol/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Macrófagos/efeitos dos fármacos , Síndrome Metabólica/metabolismo , MicroRNAs/genética , Animais , Transporte Biológico/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Feminino , Regulação da Expressão Gênica/genética , Glucose/farmacologia , Homeostase/efeitos dos fármacos , Humanos , Macrófagos/metabolismo , Masculino , Síndrome Metabólica/genética , Camundongos , Pessoa de Meia-Idade , Células RAW 264.7
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