Quantitative imaging of fibrotic and morphological changes in liver of non-alcoholic steatohepatitis (NASH) model mice by second harmonic generation (SHG) and auto-fluorescence (AF) imaging using two-photon excitation microscopy (TPEM) (original) (raw)
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Hepatology (Baltimore, Md.), 2017
There is a need for further refinement of current histological systems for assessment of hepatic fibrosis in nonalcoholic fatty liver disease (NAFLD). This study evaluated hepatic fibrosis in NAFLD using dual photon microscopy based quantitation of fibrosis-related parameters (q-FPs). Fifty (test cohort) and 42 (validation cohort) subjects with NAFLD and the full spectrum of fibrosis were studied. Q-FPs were measured in specific predefined regions of interest (general, vessel, perisinusoid and vascular septa). Seventy q-FPs had inter- and intra-observer concordance ≥0.8 and were related to the NASH CRN fibrosis staging. Of these, 16 q-FPs with the strongest correlations (p<0.001 for all) were entered in a principal component analysis model (Odds ratio [OR] 7.8, p<0.001), which separated any stage of fibrosis versus no fibrosis, and cirrhosis versus earlier stages with the areas under receiver-operating-characteristic curves of 0.88 and 0.93 (p≤0.01 for both), respectively. In ...
Scientific reports, 2014
The accurate staging of liver fibrosis is of paramount importance to determine the state of disease progression, therapy responses, and to optimize disease treatment strategies. Non-linear optical microscopy techniques such as two-photon excitation fluorescence (TPEF) and second harmonic generation (SHG) can image the endogenous signals of tissue structures and can be used for fibrosis assessment on non-stained tissue samples. While image analysis of collagen in SHG images was consistently addressed until now, cellular and tissue information included in TPEF images, such as inflammatory and hepatic cell damage, equally important as collagen deposition imaged by SHG, remain poorly exploited to date. We address this situation by experimenting liver fibrosis quantification and scoring using a combined approach based on TPEF liver surface imaging on a Thioacetamide-induced rat model and a gradient based Bag-of-Features (BoF) image classification strategy. We report the assessed performa...
Multiphoton microscopy in defining liver function
Journal of biomedical optics, 2014
Multiphoton microscopy is the preferred method when in vivo deep-tissue imaging is required. This review presents the application of multiphoton microscopy in defining liver function. In particular, multiphoton microscopy is useful in imaging intracellular events, such as mitochondrial depolarization and cellular metabolism in terms of NAD(P)H changes with fluorescence lifetime imaging microscopy. The morphology of hepatocytes can be visualized without exogenously administered fluorescent dyes by utilizing their autofluorescence and second harmonic generation signal of collagen, which is useful in diagnosing liver disease. More specific imaging, such as studying drug transport in normal and diseased livers are achievable, but require exogenously administered fluorescent dyes. If these techniques can be translated into clinical use to assess liver function, it would greatly improve early diagnosis of organ viability, fibrosis, and cancer.
Imaging Fibrogenesis in a Diet-Induced Model of Nonalcoholic Steatohepatitis (NASH)
Contrast Media & Molecular Imaging, 2019
Purpose. Liver fibrosis is the hallmark of chronic nonalcoholic steatohepatitis (NASH) and is characterised by the excessive deposition of extracellular matrix proteins. Early detection and accurate staging of liver fibrosis is critically important for patient management. One of the earliest pathological markers in NASH is the activation of hepatic stellate cells (HSCs) which may be exploited as a marker of fibrogenesis. Activated HSCs secreting factors such as integrin αvβ3 propagate fibrosis. The purpose of the current study was to assess the utility of the integrin αvβ3 imaging agent [18F]FtRGD for the early detection of fibrosis in a diet-induced model of NASH longitudinally using PET imaging. Procedures. Mice were fed with either standard chow diet (SD), high-fat diet (HFD), or a choline-deficient, L-amino acid-defined high-fat fibrogenic diet (CDAHFD) to mimic the clinical pathology of liver disease and followed longitudinally for 10 weeks to assess the development of liver fi...
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Biomedical Optics Express, 2015
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