Arrest of progression of pre‐induced abdominal aortic aneurysm in apolipoprotein E‐deficient mice by low level laser phototherapy. Issue 10 (19th November 2014)

• Record Type: Journal Article
• Authors: Gavish, Lilach; Beeri, Ronen; Gilon, Dan; Rubinstein, Chen; Berlatzky, Yacov; Bulut, Atilla; Reissman, Petachia; Gavish, Leah Y.; Gertz, S. David
• Is Part Of: Lasers in surgery and medicine. Volume 46:Issue 10(2014)
• Page Start: 781
• Page End: 790
• Publication Date: 2014-11-19
• Subjects: Lasers in medicine -- Periodicals; Lasers in surgery -- Periodicals; 617
• DOI: 10.1002/lsm.22306
• Languages: English
• ISSNs: 0196-8092

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="lsm22306-sec-0001" sec-type="section"> <title>Background and Objectives</title> <p>Using non‐invasive, high‐frequency ultrasonography (HF‐u/s), we showed that low‐level laser phototherapy (LLL) inhibits <italic>de‐novo</italic> formation of abdominal aortic aneurysms (AAA) in apolipoprotein‐E‐deficient (Apo‐E<sup>‐/‐</sup>) mice. The current study tests the effect of LLL on the progression of <italic>pre‐induced</italic> AAA.</p> </sec> <sec id="lsm22306-sec-0002" sec-type="section"> <title>Study Design/Material and Methods</title> <p>AAA was induced in Apo‐E<sup>‐/‐</sup> mice (age16–20 weeks) by subcutaneous infusion of angiotensin‐II using osmotic minipumps (1000 ng/kg/minutes, 4 weeks). HF‐u/s (40 MHz, 0.01 mm resolution, Vevo‐770, VisualSonics) was used to measure the maximum cross‐sectional‐diameter (MCD) of the suprarenal abdominal aorta, the anterior wall displacement (AWD), and radial wall velocity (RWV). The aortas of mice that developed >35% dilatation at 2 weeks over baseline were exposed retroperitoneally and treated with LLL (780 nm, 2.2 J/cm<sup>2</sup>, 9 minutes) or sham‐operated. HF‐u/s was repeated at 4 weeks, the mice sacrificed by perfusion fixation, and the aortas excised for histopathology.</p> </sec> <sec id="lsm22306-sec-0003" sec-type="section"> <title>Results</title> <p>Of all mice with >35% MCD expansion of the suprarenal aorta at 2 weeks, 7(58%) of 12 non‐treated, but only 1(7%) of 14 LLL, had increased MCD(> 1 SD) at 4 weeks (<italic>P</italic> < 0.009 by Fisher's Exact Test [FET]). The mean change in MCD from 2–4 weeks was also markedly reduced in the LLL‐treated mice (control vs. LLL, 0.24 ± 0.25 vs. −0.06 ± 0.39mm, <italic>P</italic> = 0.029 by unpaired <italic>t</italic>‐test). Similar results were obtained when limiting the analysis to animals with ≥50% expansion at 2 weeks. The deterioration in AWD from 2–4 weeks in non‐treated controls was not observed in LLL‐treated animals (ΔAWD: control, 0.03 ± 0.05 mm, <italic>P</italic> < 0.036 vs. LLL, 0.00 ± 0.05, <italic>P</italic> = 0.91 by paired <italic>t</italic>‐test). By the modified Daugherty classification, we found significantly fewer severe aneurysms at 4 weeks in the LLL‐treated animals versus control (3 of 10 vs. 9 of 11, <italic>P</italic> = 0.03 by FET).</p> </sec> <sec id="lsm22306-sec-0004" sec-type="section"> <title>Conclusions</title> <p>LLL not only prevents <italic>de novo</italic> development of AAA, but, from this study, also arrests further progression of <italic>pre‐induced</italic> AAA and its associated deterioration in the biomechanical integrity of the aortic wall in Apo‐E<sup>‐/‐</sup> mice. Lasers Surg. Med. 46:781–790, 2014. © 2014 Wiley Periodicals, Inc.</p> </sec> </abstract>