1) The document examines how 17β-estradiol may reduce vascular inflammation by down-regulating the NLRP3 inflammasome and related proinflammatory cytokines like IL-6 and IL-8 in human umbilical vein endothelial cells (HUVECs) and aortic smooth muscle cells (AOSMCs). 2) Exogenous 17β-estradiol was shown to significantly decrease expression of NLRP3, caspase-1, and IL-1β in HUVECs and also reduced IL-1β, IL-6, and IL-8 levels in AOSMCs. 3) Down-regulation of the NLRP3 inflammasome and proinflammatory cytokines by estrogen may be one mechanism for

1. Contact
Name : George Gkoumas
Email : giorgosgoumas92@gmail.com
Gender difference in inflammatory disease such as CVD has been reported both in
human and experimental animals. The gender specific role of estrogen has been
reflected in vascular injury response. Since observational studies have shown
substantial benefits of estrogen in reducing the relative risk of Coronary heart
disease (CHD) by 50%, we examined the effects of estradiol on NLRP3
inflammasome components and inflammatory cytokines in vascular cells.
Introduction
The present study indicates that 17β-estradiol may play an important role in the
regulation of vascular inflammation both by modulating the NLRP3 inflammasome
components and proinflammatory cytokines such as IL-6 and IL-8. Down
regulation of NLRP3 inflammasome and proinflammatory cytokines might be one
of the mechanisms of the protective effect of estrogen on cardiovascular system.
Results
References
17β-estradiol reduces vascular inflammation through the regulation
of NLRP3 inflammasome in HUVEC and AOSMC
George Gkoumas1, 2, Geena Paramel Varghese2, Karin fransén2, Allan sirsjö2
1. Varghese G, Fransén K, Hurtig-Wennlöf A, Bengtsson T, Jansson J, Sirsjö A.
(2013).”Q705K variant in NLRP3 gene confers protection against myocardial
infarction in female individuals." Biomedical Reports 1(6): 879-882.
2. Xing D, Susan N, Yiu-Fai C, Fadi H. (2009). "Estrogen and mechanisms of
vascular protection." Arterioscler Thromb Vasc Biol 29(3): 289-295.
1Department of Medical Laboratories, Biomedical Laboratory Technologist – Technological Educational Institute
of Athens, Greece. 2School of Health and Medical Sciences, Örebro University, Sweden 10/12/2013.
AOSMC and HUVEC were grown in estrogen free medium before the assay. Due
to the low basal expression of NLRP3 inflammasome components in HUVEC, the
effect of estrogen was examined by stimulating the cells with TNFα. Real time
PCR and ELISA was performed to analyze the mRNA expression and IL-1β, IL-6
and IL-8 protein.
Methods
Exogenous 17β -estradiol significantly down regulated the expression of NLRP3,
caspase-1 and IL-1β in HUVEC and AOSMC. In AOSMC, the treatment of
estrogen resulted in a moderate reduction of IL-1β release and significant reduction
of IL-6 and IL-8 levels.
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Relative expression of NLRP3 in HUVEC
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Relative expression of caspase-1 in HUVEC
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Relative expression of IL-1β in HUVEC
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IL-8 levels in HUVEC
Fig 4: IL-8 levels in the HUVEC culture medium
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IL-6 levels in AOSMC
Fig 5: IL-6 levels in the AOSMC culture medium
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Fig 6: IL-8 levels in the AOSMC culture medium
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IL-1β relative expression
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Caspase-1 relative expression
Fig 7: Relative expression of Caspase-1 in Aortic Smooth Muscle Cells
after normalization with a house-keeping gene (GAPDH)
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Conclusion
Figure 2: Plaque progression.
Figure 1: Pathway for the activation of NLRP3
inflammasome complex: The activation can be triggered by
many factors such as crystalline stucture, muramyldipeptide
(MDP), ATP, reactive oxygen species (ROS) and pathogen
associated molecular patterns (PAMPS). The NLRP3
inflammasome activates IL-1β via pro-caspase 1, triggering
the activation of caspase 1 and the maturation and secretion
of pro-inflammatory cytokines such as interleukin-1β (IL-1β)
and IL-18.
Figure 3: Plaque rupture and thrombosis.
Fig 2: Relative expression of Caspase 1 in Human Umbilical Vein
Endothelial Cells after normalization with a house-keeping gene
(Cyclophilin A)
Fig 1: Relative expression of NLRP3 in Human Umbilical Vein
Endothelial Cells after normalization with a house-keeping gene
(Cyclophilin A)
Fig 3: Relative expression of IL-1β in Human Umbilical Vein Endothelial
Cells after normalization with a house-keeping gene (Cyclophilin A)
Fig 8: Relative expression of IL-1β in Aortic Smooth Muscle Cells
after normalization with a house-keeping gene (GAPDH)
Aim
The aim of this study was to examine the effects of estradiol on NLRP3
inflammasome components and proinflammatory cytokines in vascular cells.