MODULATION OF IGF AND IGF BINDING PROTEIN EXPRESSION BY HYPOXIA IN CULTURED VASCULAR ENDOTHELIAL CELLS (EC). † 2333

Astronauts are reported to have experienced some impairment in visual acuity during their mission on the International Space Station (ISS) and after they returned to Earth. There is emerging evidence that changes in vision may involve alterations in ocular structure and function. To investigate possible mechanisms, changes in protein expression profiles and oxidative stress-associated apoptosis were examined in mouse ocular tissue after spaceflight. Nine-week-old male C57BL/6 mice (n = 12) were launched from the Kennedy Space Center on a SpaceX rocket to the ISS for a 35-day mission. The animals were housed in the mouse Habitat Cage Unit (HCU) in the Japan Aerospace Exploration Agency (JAXA) “Kibo” facility on the ISS. The flight mice lived either under an ambient microgravity condition (µg) or in a centrifugal habitat unit that produced 1 g artificial gravity (µg + 1 g). Habitat control (HC) and vivarium control mice lived on Earth in HCUs or normal vivarium cages, respectively. Quantitative assessment of ocular tissue demonstrated that the µg group induced significant apoptosis in the retina vascular endothelial cells compared to all other groups (p < 0.05) that was 64% greater than that in the HC group. Proteomic analysis showed that many key pathways responsible for cell death, cell repair, inflammation, and metabolic stress were significantly altered in µg mice compared to HC animals. Additionally, there were more significant changes in regulated protein expression in the µg group relative to that in the µg + 1 g group. These data provide evidence that spaceflight induces retinal apoptosis of vascular endothelial cells and changes in retinal protein expression related to cellular structure, immune response and metabolic function, and that artificial gravity (AG) provides some protection against these changes. These retinal cellular responses may affect blood–retinal barrier (BRB) integrity, visual acuity, and impact the potential risk of developing late retinal degeneration.

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Low Shear Stress Upregulates CX3CR1 Expression by Inducing VCAM-1 via the NF-κB Pathway in Vascular Endothelial Cells

Cell Biochemistry and Biophysics ◽

10.1007/s12013-020-00931-4 ◽

2020 ◽

Vol 78 (3) ◽

pp. 383-389 ◽

Cited By ~ 1

Author(s):

Yiwei Zhao ◽

Peile Ren ◽

Qiufang Li ◽

Shafiu Adam Umar ◽

Tan Yang ◽

...

Keyword(s):

Endothelial Cells ◽

Shear Stress ◽

Protein Expression ◽

Vascular Endothelial Cells ◽

Critical Role ◽

Mrna Levels ◽

Vascular Endothelial ◽

Low Shear Stress ◽

Low Shear ◽

Cx3cr1 Expression

Abstract Atherosclerosis is a significant cause of mortality and morbidity. Studies suggest that the chemokine receptor CX3CR1 plays a critical role in atherogenesis. Shear stress is an important mechanical force that affects blood vessel function. In this study, we investigated the effect of shear stress on CX3CR1 expression in vascular endothelial cells (VECs). First, cells were exposed to different shear stress and then CX3CR1 mRNA and protein were measured by quantitative RT-PCR and western blot analysis, respectively. CX3CR1 gene silencing was used to analyze the molecular mechanisms underlying shear stress-mediated effects on CX3CR1 expression. CX3CR1 mRNA and protein expression were significantly increased with 4.14 dyne/cm2 of shear stress compared with other tested levels of shear stress. We observed a significant increase in CX3CR1 mRNA levels at 2 h and CX3CR1 protein expression at 4 h. CX3CR1-induced VCAM-1 expression in response to low shear stress by activating NF-κB signaling pathway in VECs. Our findings demonstrate that low shear stress increases CX3CR1 expression, which increases VCAM-1 expression due to elevated NF-κB activation. The current study provides evidence of the correlation between shear stress and atherosclerosis mediated by CX3CR1.

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Angiotensin II inhibits the protein expression of ZO‑1 in vascular endothelial cells by downregulating VE‑cadherin

Molecular Medicine Reports ◽

10.3892/mmr.2018.8991 ◽

2018 ◽

Cited By ~ 1

Author(s):

Longbin Liu ◽

Liping Meng ◽

Peng Zhang ◽

Hui Lin ◽

Jufang Chi ◽

...

Keyword(s):

Endothelial Cells ◽

Angiotensin Ii ◽

Protein Expression ◽

Vascular Endothelial Cells ◽

Vascular Endothelial

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Modulation by retinoic acid of insulin-like growth factor (IGF) and IGF binding protein expression in human SK-N-SH neuroblastoma cells

Acta Endocrinologica ◽

10.1530/eje.0.1340474 ◽

1996 ◽

Vol 134 (4) ◽

pp. 474-480 ◽

Cited By ~ 24

Author(s):

Sylvie Babajko ◽

Michel Binoux

Keyword(s):

Retinoic Acid ◽

Growth Factor ◽

Protein Expression ◽

Binding Protein ◽

Neuroblastoma Cells ◽

Insulin Like Growth Factor ◽

Igf Binding ◽

Igf Receptor ◽

Igf Binding Protein

Babajko S, Binoux M. Modulation by retinoic acid of insulin-like growth factor (IGF) and IGF binding protein expression in human SK-N-SH neuroblastoma cells. Eur J Endocrinol 1996;134:474–80. ISSN 0804–4643 Growth in neuroblastoma cells is regulated by insulin-like growth factors (IGFs) whose action is modulated by IGF binding proteins (IGFBPs). In this study, SK-N-SH neuroblastoma cells were shown to produce IGF-II, IGFBP-2, IGFBP-4 and small quantities of IGFBP-6. We have studied the effects of a natural morphogen, retinoic acid (RA), on growth and IGFBP expression in these cells. In all experiments, cells were cultured in serum-free medium and treated with 1 μmol/l RA for 12 h. Cell number increased by almost 50% during the first 24 h after the beginning of treatment. This stimulation was inhibited by 80% or more in the presence of the anti-type 1 IGF receptor antibody α-IR3 and anti-IGF-II antibody. The IGF-II concentrations in the culture media, measured after acidic gel filtration, increased about 1.5-fold and Northern blotting showed a concomitant increase in IGF-II mRNA levels. The mitogenic effect of RA therefore reflects its stimulation of IGF-II production. The availability of IGF-II to the cells may also be enhanced because of the proteolysis of IGFBP-2 to which it is bound. After this initial phase, proliferation ceased despite continued IGF-II production between 24 and 72 h. Both IGFBP-2 and IGFBP-4 production decreased, whereas that of IGFBP-6 increased. These changes appeared both in the protein quantities and in their mRNAs. Insulin-like growth factor binding protein 6 has a strong affinity for IGF-II, 5–10 times that of IGFBP-2 and at least 10 times that of the type 1 IGF receptor, and the arrested proliferation may result, at least in part, from sequestration by IGFBP-6 of the IGF-II secreted. Sylvie Babajko, INSERM U142, Hôpital Saint Antoine, 184 rue du Faubourg, St Antoine, 75571 Paris Cedex 12, France

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