A research team from the National Cheng Kung University (NCKU), based in Tainan, found that obesity causes a reduction of a protein called lysyl oxidase (LOX) that promotes acceleration of aortic stiffness and aging, causing arteriosclerosis, a serious threat to health. The research team was lead by Professor Yau-Sheng Tsai of the NCKU Institute of Clinical Medicine, with a goal to understand the pathophysiological connection between obesity and arteriosclerosis. The study, titled, “Increased Aortic Stiffness and Attenuated Lysyl Oxidase Activity in Obesity” is published in the journal Arteriosclerosis, Thrombosis, and Vascular Biology, a renowned journal in the field of cardiovascular health.
Obesity, on its own, can cause a myriad of health problems. Having increased aortic stiffness, as in arteriosclerosis, can cause sudden death, and is a chief cause of death in patients with cardiovascular disease. Professor Tsai explains, “Blood vessel elasticity requires cross-linking between elastin, of which LOX is a key.” Investigators found that obesity promotes a reduction in LOX expression and, as a consequence, a reduction in elastic fiber strength and level of cross-linkage, and an increase in elastin fragmentation and elastolytic activity.
Furthermore, the researchers observed that the aortas of obese mice models were surrounded by a large amount of pro-oxidative and pro-inflammatory perivascular adipose tissue. Through in vitro tests, researchers found that “conditioned medium from differentiated adipocytes or the perivascular adipose tissue of obese mice decreases LOX activity,” as it can be read in the press release, which suggests a connection between LOX down regulation, obesity, and aortic stiffening.
Tsai explained that despite the general public’s awareness of cardiovascular diseases, they usually worry about atherosclerosis – the occlusion of blood vessels with fatty plaque, and ignore all the dangers that reduced vascular elasticity can cause.
Other Recent Studies Regarding Obesity
A new and surprising study suggests that obesity, in certain people, does not cause the metabolic changes known to lead to diabetes, stroke or heart disease complications. The study was published January 2, 2015 in The Journal of Clinical Investigation and was authored by a research team from the Washington University School of Medicine in St. Louis.