• Molecules and Cells
• /
• 제45권12호
• /
• pp.950-962
• /
• 2022

Aging is a major risk factor for common neurodegenerative diseases. Although multiple molecular, cellular, structural, and functional changes occur in the brain during aging, the involvement of caveolin-2 (Cav-2) in brain ageing remains unknown. We investigated Cav-2 expression in brains of aged mice and its effects on endothelial cells. The human umbilical vein endothelial cells (HUVECs) showed decreased THP-1 adhesion and infiltration when treated with Cav-2 siRNA compared to control siRNA. In contrast, Cav-2 overexpression increased THP-1 adhesion and infiltration in HUVECs. Increased expression of Cav-2 and iba-1 was observed in brains of old mice. Moreover, there were fewer iba-1-positive cells in the brains of aged Cav-2 knockout (KO) mice than of wild-type aged mice. The levels of several chemokines were higher in brains of aged wild-type mice than in young wild-type mice; moreover, chemokine levels were significantly lower in brains of young mice as well as aged Cav-2 KO mice than in their wild-type counterparts. Expression of PECAM1 and VE-cadherin proteins increased in brains of old wild-type mice but was barely detected in brains of young wild-type and Cav-2 KO mice. Collectively, our results suggest that Cav-2 expression increases in the endothelial cells of aged brain, and promotes leukocyte infiltration and age-associated neuroinflammation.

• Biomolecules & Therapeutics
• /
• 제12권4호
• /
• pp.221-227
• /
• 2004

Nonsteroidal anti-inflammatory drugs (NSAIDs), particularly the highly selective cyclooxygenase (COX)-2 inhibitors have been shown to decrease the growth of tumor, in part, by inhibition of neovascularization. Recently, besides mature endothelial cells, endothelial progenitor cells (EPCs) have been shown to contribute neovascularization in angiogenic tissues. In this study, we addressed a question whether nimesulide, a selective COX-2 inhibitor, could affect differentiation of EPCs into adhesive endothelial cells in vitro. Total mononuclear cells were isolated from cord blood by Ficoll density gradient centrifugation, and then the cells were incubated with nimesulide or vehicle control for 7 days. The number of adherent and spindle-shaped cells decreased by nimesulide treatment in a concentration-dependent fashion at a concentration range of 5 - 200 ${\mu}M$. Moreover, the adherent cells double positive for DiI-ac-LDL uptake and lectin binding significantly decreased upon nimesulide treatment. There was no change of expression of CD31 between treatment and control groups, whereas slight reduction was detected upon treatment in expression of VE-cadherin, ICAM-1, vWF, ${\alpha}v$, and ${\alpha}5$. Nimesulide also reduced cell viability during first 3 days' culture and induced apoptosis in adherent EPCs, resulting in increased annexin-V-positive and propidium iodide-negative cells. Taken together, these results suggest that nimesulide could be applied for the inhibition of new vessel formation, in part, by inhibiting differentiation and survival of EPCs.

• Biomolecules & Therapeutics
• /
• 제27권5호
• /
• pp.474-483
• /
• 2019

Vascular endothelial growth factor (VEGF) plays a pivotal role in pathologic ocular neovascularization and vascular leakage via activation of VEGF receptor 2 (VEGFR2). This study was undertaken to evaluate the therapeutic mechanisms and effects of the tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a VEGFR2 inhibitor, in the development of vascular permeability and choroidal neovascularization (CNV). In cultured human retinal microvascular endothelial cells (HRMECs), treatment with RLYE blocked VEGF-A-induced phosphorylation of VEGFR2, Akt, ERK, and endothelial nitric oxide synthase (eNOS), leading to suppression of VEGF-A-mediated hyper-production of NO. Treatment with RLYE also inhibited VEGF-A-stimulated angiogenic processes (migration, proliferation, and tube formation) and the hyperpermeability of HRMECs, in addition to attenuating VEGF-A-induced angiogenesis and vascular permeability in mice. The anti-vascular permeability activity of RLYE was correlated with enhanced stability and positioning of the junction proteins VE-cadherin, ${\beta}$-catenin, claudin-5, and ZO-1, critical components of the cortical actin ring structure and retinal endothelial barrier, at the boundary between HRMECs stimulated with VEGF-A. Furthermore, intravitreally injected RLYE bound to retinal microvascular endothelium and inhibited laser-induced CNV in mice. These findings suggest that RLYE has potential as a therapeutic drug for the treatment of CNV by preventing VEGFR2-mediated vascular leakage and angiogenesis.