EOLA1 Inhibits Lipopolysaccharide-Induced Vascular Cell Adhesion Molecule-1 Expression by Association with MT2A in ECV304 Cells

Our research group firstly discovered endothelial-overexpressed lipopolysaccharide-associated factor 1 (EOLA1, GenBank number AY074889) as a lipopolysaccharide (LPS) responsive gene in ECV304 cells. The previous studies have further demonstrated the association of EOLA1 with metallothionein 2A (MT2A), while the role of EOLA1 during LPS-induced inflammatory response in ECV304 cells is unknown. In this report, we determined the subcellular localization of EOLA1 and the regulatory capacity of EOLA1 on vascular cell adhesion molecule-1 (VCAM-1) in response to LPS in ECV304 cells. Our results show that EOLA1 is broadly diffuse in the cells, and EOLA1 expression is dramatically induced by LPS. EOLA1 knockdown results in significant enhancement of LPS-induced VCAM-1 production. Consistent with this, overexpression of EOLA1 leads to the reduction of LPS-induced VCAM-1 production. Furthermore, MT2A knockdown reduces LPS-induced VCAM-1 production. Collectively, our results demonstrate a negative regulatory role of EOLA1 on LPS-induced VCAM-1 expression involving its association with MT2A in ECV304 cells

EOLA1 Inhibits Lipopolysaccharide-Induced Vascular Cell Adhesion Molecule-1 Expression by Association with MT2A in ECV304 Cells

Our research group firstly discovered endothelial-overexpressed lipopolysaccharide-associated factor 1 (EOLA1, GenBank number AY074889) as a lipopolysaccharide (LPS) responsive gene in ECV304 cells. The previous studies have further demonstrated the association of EOLA1 with metallothionein 2A (MT2A), while the role of EOLA1 during LPS-induced inflammatory response in ECV304 cells is unknown. In this report, we determined the subcellular localization of EOLA1 and the regulatory capacity of EOLA1 on vascular cell adhesion molecule-1 (VCAM-1) in response to LPS in ECV304 cells. Our results show that EOLA1 is broadly diffuse in the cells, and EOLA1 expression is dramatically induced by LPS. EOLA1 knockdown results in significant enhancement of LPS-induced VCAM-1 production. Consistent with this, overexpression of EOLA1 leads to the reduction of LPS-induced VCAM-1 production. Furthermore, MT2A knockdown reduces LPS-induced VCAM-1 production. Collectively, our results demonstrate a negative regulatory role of EOLA1 on LPS-induced VCAM-1 expression involving its association with MT2A in ECV304 cells

The Reduced Expression of EOLA1 May Be Related to Refractory Diabetic Foot Ulcer

Background. Chronic diabetic foot ulcer (DFU) is one of the most intractable complications of diabetes mellitus (DM). Its pathogenesis is complex, and uncontrolled chronic inflammation is an important factor. Endothelial overexpressed lipopolysaccharide-associated factor 1 (EOLA1) discovered in our laboratory is an intracellular protein with the function of inflammatory regulation. This study was aimed at observing the expression of EOLA1 in DFU skin tissues and its relationship with inflammation and at exploring the possible role of EOLA1 in DFU and its mechanism. Methods. The patients with DFU were divided into 2 groups based on the formation time of ulcer: the acute wound (AW) group with the course of disease≤4 weeks and the chronic wound (CW) group with the course of disease>4 weeks. The relevant clinical data of patients were collected, and the skin tissues around the ulcer were used for immunofluorescence detection and immunohistochemical staining to observe inflammation. The expression levels of EOLA1, metallothionein 2A (MT2A), nuclear factor-κB (NF-κB), and interleukin-6 (IL-6) were detected by western blot. Results. A total of 79 patients were enrolled in the study. The results of immunofluorescence and immunohistochemistry showed that EOLA1 was expressed in the epithelial tissues of DFU. However, the expression of EOLA1 in the CW group was significantly lower than that in the AW group (P<0.05), and the expression of NF-κB and IL-6 was obviously increased (P<0.05). Conclusion. The refractory wounds in patients with DFU may be closely related to the uncontrolled activation of inflammatory pathways in cells caused by the reduced expression of negative regulators of inflammation (e.g., EOLA1), and such decreased expression may be also strongly linked to the persistent state of inflammation

Assessment of Left Ventricular Structural Remodelling in Patients with Diabetic Cardiomyopathy by Cardiovascular Magnetic Resonance

Background. Diabetic cardiomyopathy (DCM) is always accompanied with alteration of left ventricular structure and function. The aims of this study were to assess the structural remodelling in patients with DCM by cardiovascular magnetic resonance (CMR) and correlation of structural remodelling with severity of DCM. Methods. Twenty-five patients (53.8±8.8 years, 52.0% males) with DCM and thirty-one normal healthy controls (51.9±13.6 years, 45.2% males) were scanned by CMR cine to assess function and structure of left ventricular. Length of diabetic history and results of cardiac echocardiography (E′, A′, and E′/A′) were also measured. Results. Compared with normal controls group, DCM group was associated with significantly increased ratio of left ventricular mass at end diastole to end-diastolic volume (MVR) (P<0.05) and no significant difference was in mass at end diastole (P>0.05). The ratio correlated with both length of diabetic history and echocardiographic Doppler tissue imaging E′ (all P<0.05). Conclusions. CMR can be a powerful technique to assess LV remodelling, and MVR may be considered as an imaging marker to evaluate the severity of LV remodelling in patients with DCM

The SGLT-2 Inhibitor Dapagliflozin Has a Therapeutic Effect on Atherosclerosis in Diabetic ApoE−/− Mice

Background. Our study aimed to observe the effect of sodium glucose cotransporter-2 (SGLT2) inhibitor dapagliflozin on diabetic atherosclerosis and investigate the subsequent mechanism. Methods. Aortic atherosclerosis was induced in streptozotocin induced diabetic ApoE−/− mice by feeding with high-fat diet, and dapagliflozin was administrated intragastrically for 12 weeks as treatment. Effects of dapagliflozin on indices of glucose and fat metabolism, IL-1β, IL-18, NLRP3 protein levels, and the reactive oxygen species (ROS) were measured. The atherosclerosis was evaluated by oil red O and hematoxylin-eosin staining. The effects of dapagliflozin on the IL-1β production in culturing primary macrophages of wild type and NLRP3−/− knockout mice were investigated for mechanism analyses. Results. Dapagliflozin treatment showed favorable effects on glucose and fat metabolism, partially reversed the formation of atherosclerosis, inhibited macrophage infiltration, and enhanced the stability of lesion. Also, reduced production of IL-1β, IL-18, NLRP3 protein, and mitochondrial ROS in the aortic tissues was detected with dapagliflozin treatment. In vitro, NLRP3 inflammasome was activated by hyperglucose and hyperlipid through ROS pathway. Conclusions. Dapagliflozin may be of therapeutic potential for diabetic atherosclerosis induced by high-fat diet, and these benefits may depend on the inhibitory effect on the secretion of IL-1β by macrophages via the ROS-NLRP3-caspase-1 pathway

TERT and Akt Are Involved in the Par-4-Dependent Apoptosis of Islet β Cells in Type 2 Diabetes

Islet β cell apoptosis plays an important role in type 2 diabetes. We previously reported that Par-4-mediated islet β cell apoptosis is induced by high-glucose/fatty acid levels. In the present study, we show that Par-4, which is induced by high-glucose/fatty acid levels, interacts with and inhibits TERT in the cytoplasm and then translocates to the nucleus. Par-4 also inhibited Akt phosphorylation, leading to islet β cell apoptosis. We inhibited Par-4 in islet β cells under high-glucose/fatty acid conditions and knocked out Par-4 in diabetic mice, which led to the up-regulation of TERT and an improvement in the apoptosis rate. We inhibited Akt phosphorylation in islet β cells and diabetic mice, which led to aggressive apoptosis. In addition, the biological film interference technique revealed that Par-4 bound to TERT via its NLS and leucine zipper domains. Our research suggests that Par-4 activation and binding to TERT are key steps required for inducing the apoptosis of islet β cells under high-glucose/fatty acid conditions. Inhibiting Akt phosphorylation aggravated apoptosis by activating Par-4 and inhibiting TERT, and Par-4 inhibition may be an attractive target for the treatment of islet β cell apoptosis