RESUMO
Neuropathic pain is pain caused by damage to the somatosensory nervous system. Both degenerating injured nerves and neighboring sprouting nerves can contribute to neuropathic pain. However, the mesoscale changes in cutaneous nerve fibers over time after the loss of the parent nerve has not been investigated in detail. In this study, we followed the changes in nerve fibers longitudinally in the toe tips of mice that had undergone spared nerve injury (SNI). Nav1.8-tdTomato, Thy1-GFP and MrgD-GFP mice were used to observe the small and large cutaneous nerve fibers. We found that peripheral nerve plexuses degenerated within 3 days of nerve injury, and free nerve endings in the epidermis degenerated within 2 days. The timing of degeneration paralleled the initiation of mechanical hypersensitivity. We also found that some of the Nav1.8-positive nerve plexuses and free nerve endings in the fifth toe survived, and sprouting occurred mostly from 7 to 28 days. The timing of the sprouting of nerve fibers in the fifth toe paralleled the maintenance phase of mechanical hypersensitivity. Our results support the hypotheses that both injured and intact nerve fibers participate in neuropathic pain, and that, specifically, nerve degeneration is related to the initiation of evoked pain and nerve sprouting is related to the maintenance of evoked pain.
Assuntos
Microscopia Intravital/métodos , Degeneração Neural/patologia , Neuralgia/patologia , Neurônios Aferentes/patologia , Dedos do Pé/inervação , Dedos do Pé/patologia , Animais , Feminino , Microscopia Intravital/tendências , Estudos Longitudinais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios Aferentes/químicaRESUMO
Intravital microscopy allows the visualisation of how pathogens interact with host cells and tissues in living animals in real time. This method has enabled key advances in our understanding of host-parasite interactions under physiological conditions. A combination of genetics, microscopy techniques, and image analysis have recently facilitated the understanding of biological phenomena in living animals at cellular and subcellular resolution. In this review, we summarise findings achieved by intravital microscopy of the skin and adipose tissues upon infection with various parasites, and we present a view into possible future applications of this method.
Assuntos
Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/parasitologia , Interações Hospedeiro-Parasita , Microscopia Intravital/métodos , Pele/diagnóstico por imagem , Pele/parasitologia , Tecido Adiposo/citologia , Tecido Adiposo/patologia , Animais , Microscopia Intravital/tendências , Leishmania/metabolismo , Leishmania/patogenicidade , Plasmodium/metabolismo , Plasmodium/patogenicidade , Schistosoma/metabolismo , Schistosoma/patogenicidade , Pele/citologia , Pele/patologia , Trypanosoma/metabolismo , Trypanosoma/patogenicidadeRESUMO
Animal models have for long been pivotal for parasitology research. Over the last few years, techniques such as intravital, optoacoustic and magnetic resonance imaging, optical projection tomography, and selective plane illumination microscopy developed promising potential for gaining insights into host-pathogen interactions by allowing different visualization forms in vivo and ex vivo. Advances including increased resolution, penetration depth, and acquisition speed, together with more complex image analysis methods, facilitate tackling biological problems previously impossible to study and/or quantify. Here we discuss advances and challenges in the in vivo imaging toolbox, which hold promising potential for the field of parasitology.
Assuntos
Interações Hospedeiro-Parasita , Microscopia Intravital , Parasitologia , Animais , Microscopia Intravital/métodos , Microscopia Intravital/tendências , Parasitologia/métodos , Parasitologia/normas , Parasitologia/tendências , Tomografia ÓpticaRESUMO
Molecular mobility, localisation and spatiotemporal activity are at the core of cell biological processes and deregulation of these dynamic events can underpin disease development and progression. Recent advances in intravital imaging techniques in mice are providing new avenues to study real-time molecular behaviour in intact tissues within a live organism and to gain exciting insights into the intricate regulation of live cell biology at the microscale level. The monitoring of fluorescently labelled proteins and agents can be combined with autofluorescent properties of the microenvironment to provide a comprehensive snapshot of in vivo cell biology. In this Review, we summarise recent intravital microscopy approaches in mice, in processes ranging from normal development and homeostasis to disease progression and treatment in cancer, where we emphasise the utility of intravital imaging to observe dynamic and transient events in vivo We also highlight the recent integration of advanced subcellular imaging techniques into the intravital imaging pipeline, which can provide in-depth biological information beyond the single-cell level. We conclude with an outlook of ongoing developments in intravital microscopy towards imaging in humans, as well as provide an overview of the challenges the intravital imaging community currently faces and outline potential ways for overcoming these hurdles.
Assuntos
Microscopia Intravital/tendências , Imagem Molecular/tendências , Neoplasias/genética , Microambiente Tumoral/genética , Progressão da Doença , Humanos , Neoplasias/ultraestruturaRESUMO
Intravital imaging has been increasingly employed in cell biology studies and it is becoming one of the most powerful tools for in vivo investigation. Although some protocols can be extremely complex, most intravital imaging procedures can be performed using basic surgery and animal maintenance techniques. More importantly, regular confocal microscopes - the same that are used for imaging immunofluorescence slides - can also acquire high quality intravital images and movies after minor adaptations. Here we propose minimal adaptations in stock microscopes that allow major improvements in different fields of scientific investigation.
Assuntos
Pesquisa Biomédica/instrumentação , Biologia Celular/instrumentação , Microscopia Intravital , Microscopia Confocal , Animais , Pesquisa Biomédica/tendências , Biologia Celular/tendências , Humanos , Sistema Imunitário/diagnóstico por imagem , Microscopia Intravital/instrumentação , Microscopia Intravital/tendências , Camundongos , Microscopia Confocal/instrumentação , Microscopia Confocal/tendências , Microscopia de Vídeo/instrumentação , Microscopia de Vídeo/tendênciasRESUMO
The use of reflectance confocal microscopy (RCM) and other noninvasive imaging devices can potentially streamline clinical care, leading to more precise and efficient management of skin cancer. This article explores the potential role of RCM in cutaneous oncology, as an adjunct to more established techniques of detecting and monitoring for skin cancer, such as dermoscopy and total body photography. Discussed are current barriers to the adoption of RCM, diagnostic workflows and standards of care in the United States and Europe, and medicolegal issues. The potential role of RCM and other similar technological innovations in the enhancement of dermatologic care is evaluated.