Search

Zebrafish (Danio rerio) has rapidly become a popular model species for behavioral studies that may be relevant to drug screening and safety toxicology. Zebrafish embryos show a complex behavioral repertoire already a few hours after fertilization. Particularly, early stage zebrafish show characteristic behavioral features such as spontaneous tail coiling (STC) or induced movements when exposed to a short and bright light flash (called photomotor response—PMR). In this chapter, we provide the methods for assessing STC and PMR in zebrafish embryos and to detect changes provoked by chemicals. One of the protocols uses video analysis suitable for automated high-throughput screening. Moreover, both protocols describe the use of automated video analysis by using an open-source integration platform (KNIME® analytics platform), providing a flexible workflow system that can be adapted to a diversity of video recordings. We also provide a toxicological validation of this assay and show that these protocols can be used to provide an automated, high data-content readout for zebrafish behavioral responses.

Chemotherapy-Induced Peripheral Neurotoxicity (CIPN) is a side effect frequently caused by common antitumor drugs, which may induce a severe and persistent limitation of the quality of life of cancer patients. Today, nerve conduction studies are considered the most objective indicators for CIPN diagnosis. Unfortunately, they are not easily available at most oncology centers. Therefore, a noninvasive and highly sensitive method is required to confirm nerve damage. Increased evidence supports the potential utility of fluid-based biomarkers to predict tissue damage and to monitor neurotoxicity due to drug administration or the efficacy of disease-modifying treatments. Neurofilaments, the major intermediate filaments in neurons that are specifically expressed in axons, have been investigated as potential biomarker candidates that might be used for this purpose. Neurofilament light chain (NfL) protein is increasingly proposed as a blood biomarker in several neurological diseases mainly affecting the central nervous system. In addition, analysis of serum NfL was evaluated also in peripheral neuropathies including Guillain–Barré syndrome, chronic inflammatory demyelinating and vasculitic neuropathies, and Charcot–Marie–Tooth. This chapter aims to provide an overview of the methods that allow NfL quantification in serum, focusing on the most recent ultrasensitive single molecule array (Simoa) assay. This technique is likely to be the best method for NfL dosage in CIPN models to predict the onset of large caliber neuronal dysfunction. Since blood sampling is an easily accessible technique, serum NfL may provide important help to monitor neuroaxonal damage after chemotherapy treatment, and might represent promising tools to follow CIPN progress.

Chemotherapy-induced peripheral neuropathy (CIPN) is a severe side effect related to anticancer treatment, typically characterized by sensory symptoms including numbness, tingling in the distal extremities and neurophysiological impairments. CIPN is often painful, which is identified by adding a second “P” to the acronym. The incidence of CIPN is variable depending on the drug, pre-existing neuropathy, and clinical history, but generally increases with the cumulative dose and can also persist after treatment discontinuation. In the last 30 years, many rodent models of CIPN have been developed reproducing the clinical features of the pathology, useful to study the mechanisms of pathogenesis and test neuroprotective strategies. In this chapter, we will focus our attention on sensitive and reproducible methods to study the pathophysiology of chemotherapy-induced painful peripheral neuropathy (CIPPN), in animal models. In particular, we describe the techniques to record nerve conduction velocity and nerve excitability parameters in peripheral nerves and the electrical activity of wide dynamic range neurons of the dorsal horn of the spinal cord in mice, as parameters of evaluation of nerve function and painful neuronal sensitization, respectively. Our intent is to provide the reader with guidelines on how to prepare and manage the animals according to the 3Rs (Reduction, Refinement, and Replacement) principles, how to record neuronal activity and analyze resulting data and describe common technical problems and appropriate solutions. These protocols can also be useful to study peripheral nerve damage and pain of other origins, such as traumatic injury, inherited, or acquired neuropathies.