+ Site Statistics
+ Search Articles
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ PDF Full Text
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Translate
+ Recently Requested

Simulated microgravity-induced aortic remodeling

Simulated microgravity-induced aortic remodeling

Journal of Applied Physiology 106(6): 2002-2008

We have previously shown that microgravity and simulated microgravity induce an increase in human and rat aortic stiffness. We attempted to elucidate the mechanism(s) responsible for this increase in stiffness. We hypothesize that an alteration in vessel wall collagen or elastin content or in extracellular matrix (ECM) cross-linking either individually or in a combination is responsible for the increased vessel stiffness. Rats underwent hindlimb unweighting (HLU) for a period of 7 days to simulate microgravity. The contribution of ECM cross-linking to the vessel wall stiffness was evaluated by measuring aortic pulse wave velocity following inhibition of the cross-linking enzymes lysyl oxidase (LOX) and transglutaminase (tTG) and the nonenzymatic advanced glycation end product cross-linking pathway during HLU. Aortic collagen and elastin content was quantified using established colorimetric assays. Collagen subtype composition was determined via immunofluorescent staining. The increase in aortic pulse wave velocity after HLU was significantly attenuated in the LOX and tTG inhibition groups compared with saline (1.13 +/- 0.11 vs. 3.00 +/- 0.15 m/s, LOX vs. saline, P < 0.001; 1.16 +/- 0.25 vs. 3.00 +/- 0.15 m/s, tTG vs. saline, P < 0.001). Hydroxyproline content, a measure of collagen content, was increased in all groups after HLU (2.01 +/- 0.62 vs. 3.69 +/- 0.68% dry weight, non-HLU vs. HLU, P = 0.009). Collagen subtype composition and aortic elastin content were not altered by HLU. Together, these data indicate that HLU-induced increases in aortic stiffness are due to both increased aortic collagen content and enzyme cross-linking activity.

(PDF emailed within 0-6 h: $19.90)

Accession: 055783250

Download citation: RISBibTeXText

PMID: 19299573

DOI: 10.1152/japplphysiol.90777.2008

Related references

Simulated Microgravity and Recovery-Induced Remodeling of the Left and Right Ventricle. Frontiers in Physiology 7: 274-274, 2016

Myocardial CKIP-1 Overexpression Protects from Simulated Microgravity-Induced Cardiac Remodeling. Frontiers in Physiology 9: 40-40, 2018

Structural and functional remodeling of skeletal muscle microvasculature is induced by simulated microgravity. American Journal of Physiology. Heart and Circulatory Physiology 278(6): H1866-H1873, 2000

Alterations in skeletal perfusion with simulated microgravity: a possible mechanism for bone remodeling. Journal of Applied Physiology 89(3): 1046-1054, 2000

Large artery remodeling and dynamics following simulated microgravity by prolonged head-down tilt bed rest in humans. Biomed Research International 2015: 342565-342565, 2015

Simulated microgravity inhibits the migration of mesenchymal stem cells by remodeling actin cytoskeleton and increasing cell stiffness. Cytotechnology 68(6): 2235-2243, 2016

Influence of simulated microgravity on colonic and aortic blood temperatures. FASEB Journal 9(4): A874, 1995

Aortic baroreflex control of heart rate following 15 days of simulated microgravity. FASEB Journal 7(3-4): A666, 1993

Effects of low-dose rate γ-irradiation combined with simulated microgravity on markers of oxidative stress, DNA methylation potential, and remodeling in the mouse heart. Plos One 12(7): E0180594-E0180594, 2017

Aortic baroreflex control of heart rate after 15 days of simulated microgravity exposure. Journal of Applied Physiology 77(5): 2134-2139, 1994

Simulated microgravity promotes monocyte adhesion to rat aortic endothelium via nuclear factor-κB activation. Clinical and Experimental Pharmacology & Physiology 42(5): 510-519, 2016

The progress in research on the mechanisms of the effects of blood volume reduction on orthostatic tolerance after microgravity or simulated microgravity. Hang Tian Yi Xue Yu Yi Xue Gong Cheng 13(2): 152-156, 2001

Simulated microgravity induced peroxidative injury in rat brain. FASEB Journal 13(5 PART 2): A1039, March 15, 1999

Simulated microgravity-induced epigenetic changes in human lymphocytes. Journal of Cellular Biochemistry 111(1): 123-129, 2011

Change of pulmonary circulation in microgravity and simulated microgravity. Hang Tian Yi Xue Yu Yi Xue Gong Cheng 13(4): 305-309, 2002