ABSTRACT
BACKGROUND: Polyphenol catechins from green tea, particularly (-)-epigallocatechin-3-gallate (EGCG), exhibits numerous beneficial health effects, although the mechanisms remain unclear. METHODS: In this study, the mechanism of EGCG-mediated healing in an experimentally injured zebrafish model was examined at the cellular and molecular level using confocal microscopy and gene expression analysis. RESULTS: The mechanisms of action of EGCG were shown to involve: (1) reducing neutrophil response (accumulation, travel speed, and distance) and (2) downregulating the expression of IL-1ß, TNFα, and related signaling pathways. As determined by dynamic time-lapse tracking studies, the local accumulation of neutrophils with high migration speeds after wounding (n=33 cells, v=0.020 µm/s, d=37.8 µm), underwent significant reduction following treatment with EGCG doses of 300 µM (n=22 cells, v=0.013 µm/s, d=39.5 µm) and 600 µM (n=18 cells, v=0.008 µm/s, d=9.53 µm). Reverse transcription polymerase chain reaction studies revealed that several signature genes in the IL-1ß, TNFα, and related signaling pathways were downregulated after EGCG treatment. CONCLUSION: The convenience, transparency, and simplicity of the zebrafish model facilitate tracking of fluorescent neutrophils in real time, in order to monitor inflammation, and assess the impact of therapeutic agents.
ABSTRACT
Autoimmune diseases occur when the immune system generates proinflammatory molecules and autoantibodies that mistakenly attack their own body. Traditional diagnosis of autoimmune disease is primarily based on physician assessment combined with core laboratory tests. However, these tests are not sensitive enough to detect early molecular events, and quite often, it is too late to control these autoimmune diseases and reverse tissue damage when conventional tests show positivity for disease. It is fortunate that during the past decade, research in nanotechnology has provided enormous opportunities for the development of ultrasensitive biosensors in detecting early biomarkers with high sensitivity. Biosensors consist of a biorecognition element and a transducer which are able to facilitate an accurate detection of proinflammatory molecules, autoantibodies and other disease-causing molecules. Apparently, novel biosensors could be superior to traditional metrics in assessing the drug efficacy in clinical trials, especially when specific biomarkers are indicative of the pathogenesis of disease. Furthermore, the portability of a biosensor enables the development of point-of-care devices. In this review, various types of biomolecule sensing systems, including electrochemical, optical and mechanical sensors, and their applications and future potentials in autoimmune disease treatment were discussed.
