Selectivity of protein carbonylation in the apoptotic response to oxidative stress associated with photodynamic therapy: a cell biochemical and proteomic investigation.

We previously reported that photodynamic therapy (PDT) using Purpurin-18 (Pu-18) induces apoptosis in HL60 cells. Using flow cytometry, two-dimensional electrophoresis coupled with immunodetection of carbonylated proteins and mass spectrometry, we now show that PDT-induced apoptosis is associated with increased reactive oxygen species generation, glutathione depletion, changes in mitochondrial transmembrane potential, simultaneous downregulation of mitofilin and carbonylation of specific proteins: glucoseregulated protein-78, heat-shock protein 60, heat-shock protein cognate 71, phosphate disulphide isomerase, calreticulin, b-actin, tubulin-a-1-chain and enolase-a. Interestingly, all carbonylated proteins except calreticulin and enolase-a showed a pI shift in the proteome maps. Our results suggest that PDT with Pu-18 perturbs the normal redox balance and shifts HL60 cells into a state of oxidative stress, which systematically induces the carbonylation of specific chaperones. As these proteins normally produce a prosurvival signal during oxidative stress, we hypothesize that their carbonylation represents a signalling mechanism for apoptosis induced by PDT

Olfactory deficit and hippocampal volume loss for early diagnosis of Alzheimer's disease

To verify the role of olfactory test and volumetric MRI measure of hyppocampus to predict conversion from mild cognitive impairment (MCI) to Alzheimer’s Disease (A

In vitro and in vivo characterization of graphene oxide coated porcine bone granules

Graphene oxide (GO) demonstrated to improve the wound healing properties of materials intended for bone replacement. The main objective of this study was the setting up of a simple and effective procedure for the production of GO-coated porcine bone (PB) granules and the characterization of the obtained material in order to improve its properties by exploiting chemical, physical, biological and mechanical features that the GO coating could confer to pre-formed PB granules. The obtained coating was homogeneously distributed on PB granule surface and demonstrated to confer PB an increased resistance to fracture load. Biological analyses evidenced no toxic effects of GO-coated PB samples on primary human gingival fibroblasts, and no inflammatory response around the grafted particles when implanted in vivo on a sheep model although GO-coated PB samples did not appear to improve new bone formation efficacy compared with the control within the investigated time. A small loss of GO was however detected, indicating the opportunity to investigate less GO concentrated samples. In conclusion, this study presents a novel and low cost approach to the development of functionalized biomimetic hybrid materials which can be applied to other bone substitute materials in order to improve their performances