Transcriptome changes in undifferentiated Caco-2 cells exposed to food-grade titanium dioxide (E171):contribution of the nano- and micro- sized particles

The food additive titanium dioxide (TiO2), or E171, is a white food colorant. Recent studies showed after E171 ingestion a significantly increased number of colorectal tumours in a colorectal cancer mouse model as well as inflammatory responses and dysregulation of the immune system in the intestine of rats. In the mouse colon, E171 induced gene expression changes related to oxidative stress, impairment of the immune system, activation of signalling and cancer-related processes. E171 comprises nanoparticles (NPs) and microparticles (MPs). Previous in vitro studies showed that E171, NPs and MPs induced oxidative stress responses, DNA damage and micronuclei formation. This study aimed to investigate the relative contribution of the NPs and MPs to effects of E171 at the transcriptome level in undifferentiated Caco-2 cells by genome wide microarray analysis. The results showed that E171, NPs, and MPs induce gene expression changes related to signalling, inflammation, immune system, transport and cancer. At the pathway level, metabolism of proteins with the insulin processing pathway and haemostasis were specific to E171 exposure. The gene expression changes associated with the immune system and inflammation induced by E171, MPs, and NPs suggest the creation of a favourable environment for colon cancer development

Elevated oxidative stress in patients with congenital heart disease and the effect of cyanosis : a meta-analysis

Abstract: Oxidative stress is an important pathophysiological mechanism in the development of numerous cardiovascular disorders. To improve therapy and preventive strategies, clinicians need a better understanding of the underlying pathophysiological mechanisms of congenital heart diseases (CHD). The objective of this meta-analysis was to determine whether oxidative stress is elevated in patients with CHD compared to healthy controls, and to evaluate whether a difference in oxidative stress parameters can be observed between patients with cyanotic (cCHD) and acyanotic CHD (aCHD). Therefore, 21 studies investigating oxidative stress in peripheral blood of both children and adults with CHD were reviewed. Different methods to assess the oxidant status were compared and divided into three categories: pro-oxidative or anti-oxidative stress markers and the ratio of pro-to-anti oxidative stress markers. This meta-analysis showed elevated oxidative stress levels in patients with CHD, and more specifically in patients with cCHD. Moreover, this indicates that there could be potential in oxidative stress measurements as a new biomarker of disease severity. Further research will be needed to clarify the exact role of oxidative stress and its contributors in CHD in order to get a better and more in-depth understanding of the underlying pathophysiology of CHD, especially the higher susceptibility of the right ventricle (RV) to progress to heart failure (HF). This could facilitate the development of antioxidant treatments and RV-specific HF therapies, which are necessary to improve survival in these patients and could be of particular importance in cCHD