So Daniel Anderson at the Massachusetts Institute of Technology
exposed human bone marrow stem
cells to biodegradable nanoparticles carrying the
human gene for vascular
endothelial growth factor (VEGF), which attracts blood vessels to injury sites.
Three recent experimental studies focused on low consumption / exposure.949596 In one study, 29 smokers each consumed a single cigarette, immediately after which they had a significant decrease in blood vessel output power and significant increase in blood vessel ageing level and remaining blood volume 25 minutes later, as markers of atherosclerosis.94 In another study,
human coronary artery
endothelial cells were
exposed to the smoke equivalent to one cigarette, which led to activation of oxidant stress sensing transcription factor NFR2 and up - regulation of cytochrome p450, considered to have a role in the development of heart disease.95 These effects were not seen when heart
cells were
exposed to the vapour from one e - cigarette.95 A study
exposed adult mice to low intensity tobacco smoke (two cigarettes) for one to two months and found adverse histopathological effects on brain
cells.96
There have, however, been some studies with encouraging results; for example, Chinese scientists took
human endothelial progenitor
cells exposed to resveratrol, and showed that telomerase activity increased.