fenretinide and Inflammation

Cystic fibrosis (CF) is the most common autosomal-recessive disease in Caucasians caused by mutations in the CF transmembrane regulator (CFTR) gene. Patients are usually diagnosed in infancy and are burdened with extensive medical treatments throughout their lives. One of the first documented biochemical defects in CF, which predates the cloning of CFTR gene for almost three decades, is an imbalance in the levels of polyunsaturated fatty acids (PUFAs). The principal hallmarks of this imbalance are increased levels of arachidonic acid and decreased levels of docosahexaenoic acids (DHA) in CF. This pro-inflammatory profile of PUFAs is an important component of sterile inflammation in CF, which is known to be detrimental, rather than protective for the patients. Despite decades of intensive research, the mechanistic basis of this phenomenon remains unclear. In this review we summarized the current knowledge on the biochemistry of PUFAs, with a focus on the metabolism of AA and DHA in CF. Finally, a synthetic retinoid called fenretinide (N-(4-hydroxy-phenyl) retinamide) was shown to be able to correct the pro-inflammatory imbalance of PUFAs in CF. Therefore, its pharmacological actions and clinical potential are briefly discussed as well.

Topics: Animals; Anti-Inflammatory Agents; Cystic Fibrosis; Fatty Acids, Essential; Fatty Acids, Unsaturated; Fenretinide; Humans; Inflammation

Healthy individuals can harbour microscopic tumours and dysplastic foci in different organs in an undetectable and asymptomatic state for many years. These lesions do not progress in the absence of angiogenesis or inflammation. Targeting both processes before clinical manifestation can prevent tumour growth and progression. Angioprevention is a chemoprevention approach that interrupts the formation of new blood vessels when tumour cell foci are in an indolent state. Many efficacious chemopreventive drugs function by preventing angiogenesis in the tumour microenvironment. Blocking the vascularization of incipient tumours should maintain a dormancy state such that neoplasia or cancer exist without disease. The current limitations of antiangiogenic cancer therapy may well be related to the use of antiangiogenic agents too late in the disease course. In this Review, we suggest mechanisms and strategies for using antiangiogenesis agents in a safe, preventive clinical angioprevention setting, proposing different levels of clinical angioprevention according to risk, and indicate potential drugs to be employed at these levels. Finally, angioprevention may go well beyond cancer in the prevention of a range of chronic disorders where angiogenesis is crucial, including different forms of inflammatory or autoimmune diseases, ocular disorders, and neurodegeneration.

Topics: Angiogenesis Inhibitors; Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; Apoptosis; Aspirin; Autophagy; Cellular Senescence; Chemoprevention; Disease Progression; Fenretinide; Humans; Hypoglycemic Agents; Inflammation; Metformin; Neoplasms; Polyphenols

The transcription factor nuclear factor erythroid-2 related factor 2 (Nrf2) is a dominant manager to inhibit oxidative and inflammatory damage. Fenretinide (Fen) is a novel agent, showing significant role in regulating oxidative stress and inflammatory response. However, its effects on lipopolysaccharide (LPS)-induced brain injury are still unclear. In the present study, we explored the regulatory role of Fen in LPS-triggered neuroinflammation, and the underlying molecular mechanisms. Results here indicated that Fen treatment markedly improved Nrf2 expression and nuclear translocation in mouse brain endothelial cell line bEnd.3 cells, and promoted Nrf2-antioxidant responsive element (ARE) transcription activity, as well as its down-streaming signals, which was Nrf2-dependent. Fen also exhibited cytoprotective role in LPS-stimulated bEnd.3 cells through improving anti-oxidant capacity and inhibiting inflammation by the blockage of nuclear factor-kappa B (NF-κB) signaling. Mouse model with brain injury induced by LPS, Fen administration markedly attenuated the behavior impairments, blood-brain-barrier (BBB) and the histological changes in hippocampus samples. Additionally, Fen attenuated oxidative stress and blunted inflammation in hippocampus of LPS-challenged mice. Therefore, results in the study highlighted the protective role of Fen against LPS-elicited brain injury.

Topics: Animals; Apoptosis; Behavior Rating Scale; Blood-Brain Barrier; Calcium Channels; Cytokines; Fenretinide; Glutamate-Cysteine Ligase; Glutathione Peroxidase; Glutathione Peroxidase GPX1; Hippocampus; I-kappa B Proteins; Inflammation; Lipopolysaccharides; Male; Mice; Mice, Inbred ICR; NAD(P)H Dehydrogenase (Quinone); NF-E2-Related Factor 2; NF-kappa B; Occludin; Oxidative Stress; Signal Transduction; Superoxide Dismutase; TRPV Cation Channels; Vascular Cell Adhesion Molecule-1; Zonula Occludens-1 Protein

This protocol describes microsphere-based protease assays for use in flow cytometry and high-throughput screening. This platform measures a loss of fluorescence from the surface of a microsphere due to the cleavage of an attached fluorescent protease substrate by a suitable protease enzyme. The assay format can be adapted to any site or protein-specific protease of interest and results can be measured in both real time and as endpoint fluorescence assays on a flow cytometer. Endpoint assays are easily adapted to microplate format for flow cytometry high-throughput analysis and inhibitor screening.

Topics: Animals; Biotinylation; Flow Cytometry; Fluorescence Resonance Energy Transfer; Green Fluorescent Proteins; High-Throughput Screening Assays; Humans; Inflammation; Kinetics; Microspheres; Peptide Hydrolases; Peptides; Reproducibility of Results; Temperature