Induction of Haemeoxygenase-1 Directly Improves Endothelial Function in Isolated Aortas from Obese Rats through the Ampk-Pi3k/Akt-Enos Pathway

Background/Aims: This study aimed to analyze the impact of microRNA-499 (miR-499) on the inflammatory damage of endothelial cells during coronary artery disease (CAD) via the targeting of PDCD4 through the NF-kB/ TNF-α signaling pathway. Methods: A total of 216 CAD patients (CAD group) and 90 healthy people (normal group) were enrolled in our study. Endothelial cells were collected and assigned into normal, OX-LDL, negative control (NC), miR-499 inhibitor, miR-499 mimic, PDCD4 siRNA, and miR-499 inhibitor + PDCD4 siRNA groups. The qRT-PCR and western blotting were performed to detect the mRNA and protein expression levels of PDCD4 and miR-499. The MTT assay was performed to determine cell viability, ELISA was performed to determine the expression levels of inflammatory factors, and flow cytometry assay to evaluate cell apoptosis. Results: Increased miR-499 expression and decreased PDCD4 expression in the plasma were observed in the CAD group compared with the normal group, demonstrating a negative correlation between miR-499 and PDCD4. Compared to the normal and miR-499 inhibitor groups, the survival rate of cells and PDCD4 expression were decreased; and the expressions of miR-499, IL-6, IL-8, IL-1β, TNF-α, NF-kB, VCAM-1, ICAM-1 and MCP-1 and the apoptosis rate were all elevated in the OX-LDL, NC, miR-499 mimic, PDCD4 siRNA and miR-499 inhibitor + PDCD4 siRNA groups. Compared to the OX-LDL, NC and miR-499 inhibitor + PDCD4 siRNA groups, PDCD4 expression and the survival rate of cells were increased; and the IL-6, IL-8, IL-1β, TNF-α, NF-κB, VCAM-1, ICAM-1 and MCP-1 expression levels and the apoptosis rate were all reduced in the miR-499 inhibitor group. In the PDCD4 siRNA group, PDCD4 expression and the survival rate of cells were lower, and the expression levels of IL-6, IL-8, IL-1β, TNF-α, NF-κB, VCAM-1, ICAM-1 and MCP-1 and the apoptosis rate were all higher compared with the miR-499 mimic group. In the miR-499 inhibitor + PDCD4 siRNA group, PDCD4 expression and the survival rate of cells were higher, and the expression levels of IL-6, IL-8, IL-1β, TNF-α, NF-κB, VCAM-1, ICAM-1, and MCP-1 and the apoptosis rate were all lower than those in the PDCD4 siRNA group. Conclusion: Down-regulated miR-499 expression increased PDCD4 expression and protected endothelial cells from inflammatory damage during CAD by inhibiting the NF-κB/TNF-α signaling pathway.

Section: Discussionmentioning

confidence: 99%

Effects of MicroRNA-499 On the Inflammatory Damage of Endothelial Cells During Coronary Artery Disease Via the Targeting of PDCD4 Through the NF-Κβ/TNF-α Signaling Pathway

Zhang¹,

He²,

Shi³

2017

“…We previously demonstrated that irisin may upregulate the HO-1/adiponectin axis and further activate AMPK-eNOS pathway to improve PVAT function through an endothelium-dependent pathway [12, 17]. Upregulation of HO-1/adiponectin axis could also activate the AMPK-eNOS signaling pathway [16]. In addition, we also found that blocking the AMPK-eNOS pathway could abolish beneficial effects of irisin-treated PVAT on endothelial function.…”

Section: Discussionmentioning

confidence: 83%

“…Recently, many studies have demonstrated that induction of HO-1/adiponectin axis have beneficial effects on cardiovascular disease [16]. Both HO-1 and adiponectin have powerful anti-oxidative and anti-inflammatory properties that protect endothelial dysfunction by enhancing NO production [29-32].…”

Section: Discussionmentioning

confidence: 99%

“…HO-1 is the major enzyme of heme metabolism decomposition and can be induced by various oxidative insults. Upregulation of HO-1 may induce an increase in adiponectin secretion by remodeling adipose tissue, which prevents endothelial dysfunction by its anti-oxidative and anti-inflammatory effects [14-16]. Previously, we observed that irisin improves the PVAT dysfunction from the thoracic aorta in died-induced obese mice through upregulation of the HO-1/adiponectin axis and browning of PVAT [17].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Irisin Regulates Heme Oxygenase-1/Adiponectin Axis in Perivascular Adipose Tissue and Improves Endothelial Dysfunction in Diet-Induced Obese Mice

Hou¹,

Du²,

Han

et al. 2017

Self Cite

Aims: To determine whether irisin could improve endothelial dysfunction by regulating heme oxygenase-1(HO-1)/adiponectin axis in perivascular adipose tissue (PVAT) in obesity. Methods: Male C57BL/6 mice were fed with a high-fat diet (HFD) with or without irisin treatment. Endothelium-dependent vasorelaxation of the thoracic aorta with or without PVAT (PVAT+ or PVAT–) was determined. Western blot was employed to determine the levels of HO-1 and adiponectin in PVAT. UCP-1, Cidea, and TNF-α gene expression in PVAT were tested by real-time PCR. Results: The presence of PVAT significantly impaired endothelial function in the HFD mice. Treatment of HFD mice with irisin significantly restored this impairment and improved endothelial function in vivo or ex vivo. Incubated aortic rings (PVAT-) with PVAT-derived conditioned medium (CM) from HFD mice impaired endothelial function in control mice. This impairment was prevented by incubating the aortic rings (PVAT-) from HFD mice with PVAT-derived CM from irisin. However, the beneficial effects were partly attenuated in the presence of HO-1 inhibitor and adiponectin receptor blocking peptide. Treatment of HFD mice with irisin significantly increased NO production, protein levels of HO-1 and adiponectin, mRNA expressions of UCP-1 and Cidea, and decreased superoxide production and TNF-α expression in PVAT. Conclusion: Irisin improved endothelial function by modulating HO-1/ adiponectin axis in PVAT in HFD-induced obese mice. These findings suggest that regulating PVAT function may be a potential mechanism by which irisin improves endothelial function in obesity.

“…AMP-activated protein kinase (AMPK) activation counteracts endothelial injury in endothelial cells [31-33]. C1q/TNF-related protein 9 is shown to alleviate TNFα-induced expressions of VCAM-1 and MCP-1 via AMPK activation in endothelial cells [34].…”

Section: Resultsmentioning

confidence: 99%

Interactions of TLR4 and PPARγ, Dependent on AMPK Signalling Pathway Contribute to Anti-Inflammatory Effects of Vaccariae Hypaphorine in Endothelial Cells

Sun¹,

Zhu²,

Lin³

et al. 2017

Background /Aims: Accumulating evidence indicates that endothelial inflammation is one of the critical determinants in pathogenesis of atherosclerotic cardiovascular disease. Our previous studies had demonstrated that Vaccariae prevented high glucose or oxidative stress-triggered endothelial dysfunction in vitro. Very little is known about the potential effects of hypaphorine from Vaccariae seed on inflammatory response in endothelial cells. Methods: In the present study, we evaluated the anti-inflammatory effects of Vaccariae hypaphorine (VH) on lipopolysaccharide (LPS)-challenged endothelial EA.hy926 cells. The inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), monocyte chemoattractant protein 1 (MCP-1) and vascular cellular adhesion molecule-1 (VCAM-1) were measured by real-time PCR (RT-PCR). The expressions of adenosine monophosphate-activated protein kinase (AMPK), acetyl-CoA carboxylase (ACC), toll-like receptor 4 (TLR4), peroxisome proliferator-activated receptor γ (PPARγ) were detected by Western blotting or immunofluorescence. Results: We showed that LPS stimulated the expressions of TNF-α, IL-1β, MCP-1, VCAM-1 and TLR4, but attenuated the phosphorylation of AMPK and ACC as well as PPARγ protein levels, which were reversed by VH pretreatment. Moreover, we observed that LPS-upregulated TLR4 protein expressions were inhibited by PPARγ agonist pioglitazone, and the downregulated PPARγ expressions in response to LPS were partially restored by knockdown of TLR4. The negative regulation loop between TLR4 and PPARγ response to LPS was modulated by AMPK agonist AICAR (5-Aminoimidazole-4-carboxamide riboside or acadesine) or A769662. Conclusions: Taken together, our results suggested that VH ameliorated LPS-induced inflammatory cytokines production in endothelial cells via inhibition of TLR4 and activation of PPARγ, dependent on AMPK signalling pathway.