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Alzheimer’s disease (AD) is one of the most prevalent neurodegenerative diseases, yet current therapeutic treatments are inadequate due to a complex disease pathogenesis. The plant polyphenol apigenin has been shown to have anti-inflammatory and neuroprotective properties in a number of cell and animal models; however a comprehensive assessment has not been performed in a human model of AD. Here we have used a human induced pluripotent stem cell (iPSC) model of familial and sporadic AD, in addition to healthy controls, to assess the neuroprotective activity of apigenin. The iPSC-derived AD neurons demonstrated a hyper-excitable calcium signalling phenotype, elevated levels of nitrite, increased cytotoxicity and apoptosis, reduced neurite length and increased susceptibility to inflammatory stress challenge from activated murine microglia, in comparison to control neurons. We identified that apigenin has potent anti-inflammatory properties with the ability to protect neurites and cell viability by promoting a global down-regulation of cytokine and nitric oxide (NO) release in inflammatory cells. In addition, we show that apigenin is able to protect iPSC-derived AD neurons via multiple means by reducing the frequency of spontaneous Ca2+ signals and significantly reducing caspase-3/7 mediated apoptosis. These data demonstrate the broad neuroprotective action of apigenin against AD pathogenesis in a human disease model.

Manual neuron tracing is a very labor-intensive task. In the drug screening context, the sheer number of images to process means that this approach is unrealistic. Moreover, the lack of reproducibility, objectivity, and auditing capability of manual tracing is limiting even in the context of smaller studies. We have developed fast, sensitive, and reliable algorithms for the purpose of detecting and analyzing neurites in cell cultures, and we have integrated them in software called HCA-Vision, suitable for the research environment. We validate the software on images of cortical neurons by comparing results obtained using HCA-Vision with those obtained using an established semi-automated tracing solution (NeuronJ). The effect of the Sez-6 deletion was characterized in detail. Sez-6 null neurons exhibited a significant increase in neurite branching, although the neurite field area was unchanged due to a reduction in mean branch length. HCAVision delivered considerable speed benefits and reliable traces. ' International Society for Analytical CytologyKey terms neurite tracing; neurite branching; neurite analysis; neurites; neurite outgrowth; neuron tracing; neuron analysis; cell morphology; neuron image analysis NEURITE tracing capabilities are invaluable in the drug development arena to identify compounds that display neuroprotective or neuroregenerative effects (1,2). Detailed morphological analyses of neurons are also vital for studying the normal development of dendritic and axonal arbors and for documenting neuropathological changes. Neurite arborization patterns established during development are characteristic for particular neuronal subtypes and relate to function. Neurite arbor size and shape influence the integration of synaptic inputs (3) and these, in turn, are regulated by both intrinsic developmental programs and external signals (4,5). Alterations in neurite arbors have been observed in a number of neuropathological conditions including mental retardation syndromes such as Down, Rett's and Fragile X syndromes (6), schizophrenia (7,8), and Alzheimer's disease (9).The simplest method for quantifying neurite arbors from digital micrographs involves intensity thresholding. Under controlled imaging conditions, good results can be obtained (10). However, most neurite images display noisy, low contrast areas that affect the ability to detect neurites. A recent implementation of neurite tracing by Xiong et al. used a multi-scale approach, with a Hessian matrix guiding the tracing (11). These authors report measurements of the total length of neurites and of the number of extremities. A system to study neurite dynamics has also been described (12). One of its most interesting features is the ability to correct for relatively frequent tracing mistakes by the use of a probabilistic model, making use of a mask associated with areas where pixel intensities change significantly from image to image.Here, we present a fully automated image analysis solution for generating neurite traces, for segmenting the ...

BackgroundNucleolin, as a multifunctional protein, has been demonstrated to play an oncogenic role in human hepatocellular carcinoma (HCC). The aim of this study was to investigate the expression pattern of nucleolin in HCC and determine its correlation with tumor progression and prognosis.MethodsNucleolin expression at both mRNA and protein levels in HCC and adjacent nonneoplastic tissues were respectively detected by quantitative real time polymerase chain reaction (Q-PCR), immunohistochemistry and western blotting.ResultsNucleolin expression, at both mRNA and protein levels, was significantly higher in HCC tissues than in the adjacent nonneoplastic tissues (both P < 0.001). In addition, the elevated nucleolin expression was markedly correlated with advanced tumor stage (P = 0.001), high tumor grade (P = 0.02) and serum AFP level (P = 0.008). Moreover, HCC patients with high nucleolin expression had shorter 5-year disease-free survival and shorter 5-year overall survival than those with low expression (both P < 0.001). Furthermore, the Cox proportional hazards model showed that nucleolin expression was an independent poor prognostic factor for both 5-year disease-free survival (hazards ratio [HR] = 3.696, 95% confidence interval [CI] = 1.662-8.138, P = 0.01) and 5-year overall survival (HR = 3.872, CI = 1.681-8.392, P = 0.01) in HCC.ConclusionThese results showed that the markedly and consistently increasing expression of nucleolin may be associated with aggressive characteristics of HCC, and implied that nucleolin expression may serve as a promising biochemical marker for predicting the clinical outcome of patients with this malignancy.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_175.

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