000 nam a22 4500
001 14349
100 _a20220321 pory50
200 _aDevelopment of zebrafish chemical screens to identify new modifiers of intestinal neutrophilic inflammation
_fNuno Valério Santos Silva
_gorient. Carolina Lage Crespo, António Jacinto
210 _aLisboa
_cNOVA Medical School
_d2022
330 _aInflammatory bowel diseases (IBD) with chronic infiltration of immune cells in thegastrointestinal tract are common and largely incurable. The therapeutic targeting ofIBD has been hampered by the complex causality of the disease, with environmentalinsults like cholesterol-enriched Western diets playing a critical role. In fact, current therapies are still far from optimal and have significant side effects. This encouragedus to look for alternative approaches like the use of dietary (poly)phenols (PP). PP are known for their anti-inflammatory properties in several chronic inflammatory disordersand are associated with low or absent side effects. However, due to the systemic processing of PP, the most representative molecules that reach the tissues and circulation are low-molecular-weight PP metabolites (LMWPM). Thus, the reported beneficial effects of PP are most likely due to these bioavailable molecules. Yet, the potential for LMWPM in IBD is still unexplored; and the identification of the most potent anti-inflammatory ones can constitute a lead for novel drug development and nutraceutical applications.We developedan easy-to-handle dietary cholesterol-basedin vivoassay that allows the screening of immune-modulatory therapeutics in transgeniczebrafish (ZF) models.ZF larvaewere fed with a highcholesterol diet(HCD),selectively inducingarobust and consistent infiltration of myeloid cells in larvaeintestines that is highly suitable for compound discovery efforts. The use of transgenicswith fluorescent reporter expression in neutrophils, allowedus tomonitor an acute inflammatory response in a whole organismcontext with a fully functional innate immune system. Moreover,semi-automatedimage acquisitionandquantitative image analysis allowedto categorizeanti-or pro-inflammatory compounds based on a leukocytic inflammationindex. Our HCD gut inflammation (HCD-GI) assayis simple, cost-and time-effective aswell as highly physiological.Moreover, analysisof common IBD therapeutics (Prednisolone and Mesalamine) proved the fidelity and clinical relevance of ourIBD-like intestinal inflammation model.Therefore, we took advantage of the HCD-GI assay and implemented a discovery platform to screen a portfolio of 30 LMWPMfor their immune-modulatory properties.We found 4 LMWPM with potent anti-inflammatory properties that strongly halted HCD-induced intestinal inflammation at physiologically relevant concentrations. One, ferulic acid, has been previously reported to have protective and anti-inflammatory functions in animalmodels of IBD.Finally, we developed tools to investigate intestinal functionality under chronic inflammatory states. Specifically, we developed an assay to quantify intestinal motility and peristalsis in ZF larvae after long-term HCD exposure, and a microgavageassay that can be used to investigate the effect of promising metabolites on intestinal barrier function.In conclusion, the HCD-GI discovery platform can facilitate and accelerate drug discovery efforts on IBD, by the identification of novel lead molecules with immune modulatory action on intestinal neutrophilic inflammation. We identified 4 LMWPM with anti-inflammatory potential,whose action is ready tobe investigated in functional assays underchronic feeding settings (out of the current thesis scope). These molecules constitute highly attractive and physiologicallyrelevant strategies worth it to be explored in the future for the nutritional and pharmacological management of IBD.
606 _aInflammatory Bowel Diseases
606 _aIntestinal Neutrophilic Inflammation
606 _aAcademic Dissertation
606 _aPortugal
610 _aDissertação de Mestrado
610 _aInvestigação Biomédica
610 _aNOVA Medical School
610 _aUniversidade NOVA de Lisboa
610 _a2022
700 _aSilva
_bNuno Valério Santos
702 _4727
_922304
_aCrespo
_bCarolina Lage
702 _921465
_aJacinto
_bAntónio
_4727
801 _aPT
_bNMS
_gRPC
856 _uhttp://hdl.handle.net/10362/134914
090 _a14349
942 _cDLEC
_n0