What are the cellular and molecular mechanisms underlying these processes? These questions are crucial both in fundamental and applied contexts, with important medical implications. The mechanisms and cells underlying tissue repair have thus been the focus of intense investigation. The last decades have seen rapid progress in the domain and new models emerging. Klein, L. Pharmacologic therapy for patients with chronic heart failure and reduced systolic function: review of trials and practical considerations.
Nichols, S. Early evolution of animal cell signaling and adhesion genes. Natl Acad. USA , — Adamska, M. The evolutionary origin of hedgehog proteins. CAS Google Scholar. Woolner, S. The small GTPase Rac plays multiple roles in epithelial sheet fusion — dynamic studies of Drosophila dorsal closure. Samakovlis, C. Genetic control of epithelial tube fusion during Drosophila tracheal development. Development , — This paper shows that the molecular machinery involved in dorsal closure in D.
Wood, W. Wound healing recapitulates morphogenesis in Drosophila embryos. Nature Cell Biol. Woolley, K. Conserved mechanisms of repair: from damaged single cells to wounds in multicellular tissues. Bioessays 22 , — Martin, P. Parallels between tissue repair and embryo morphogenesis. Suzuki, M. Nerve-dependent and -independent events in blastema formation during Xenopus froglet limb regeneration.
Brockes, J. Plasticity and reprogramming of differentiated cells in amphibian regeneration. Nature Rev. Cell Biol. Endo, T. A stepwise model system for limb regeneration.
Kumar, A. Molecular basis for the nerve dependence of limb regeneration in an adult vertebrate. Science , — This study found that the nerve dependence of limb regeneration results from nerves producing the protein nAG, which is a ligand for Prod 1 at the surface of blastemal cells, stimulating their proliferation. Planarian regeneration: its end is its beginning. Cell , — Google Scholar. Klapka, N. Collagen matrix in spinal cord injury. Neurotrauma 23 , Stichel, C. The CNS lesion scar: new vistas on an old regeneration barrier.
Cell Tissue Res. Grose, R. Wound-healing studies in transgenic and knockout mice. Inflammatory cells during wound repair: the good, the bad and the ugly. Trends Cell Biol. This review comprehensively synthesizes the voluminous literature on the role of the inflammatory process in wound repair, and the authors suggest that eliminating some physical components might ultimately improve tissue regeneration. Wound healing in the PU. Werner, S. Regulation of wound healing by growth factors and cytokines.
Galiano, R. Topical vascular endothelial growth factor accelerates diabetic wound healing through increased angiogenesis and by mobilizing and recruiting bone marrow-derived cells. Bluff, J. Bone marrow-derived endothelial progenitor cells do not contribute significantly to new vessels during incisional wound healing.
Opalenik, S. Fibroblast differentiation of bone marrow-derived cells during wound repair. Keratinocyte—fibroblast interactions in wound healing. Szabowski, A. Lovvorn, H. Relative distribution and crosslinking of collagen distinguish fetal from adult sheep wound repair. Levenson, S. The healing of rat skin wounds. Rubin, G. Comparative genomics of the eukaryotes. Cole, J. Early gene expression profile of human skin to injury using high-density cDNA microarrays.
Wound Repair Regen. Cooper, L. Wound healing and inflammation genes revealed by array analysis of 'macrophageless' PU. Genome Biol. Chang, H. Gene expression signature of fibroblast serum response predicts human cancer progression: similarities between tumors and wounds. PLoS Biol. Raja, K. Wound re-epithelialization: modulating keratinocyte migration in wound healing.
Chmielowiec, J. This paper describes the essential role of the HGF receptor, MET, in wound re-epithelialization: cells deficient in this protein cannot contribute to the formation of a neo-epidermis. The function of KGF in morphogenesis of epithelium and reepithelialization of wounds. I, macroscopic image of the arm tip. Scale bar: 5 mm. II: Hematoxylin and eosin stained longitudinal section showing the well developed nervous g: ganglia and muscle m elements.
At this stage of regeneration, a normal arm structure is fully restored. Immediately after healing, the process of arm regeneration starts and already 3 days after injury a little knob at the cutting point is visible. This later elongates forming a small protrusion. The first well-identifiable structure has the shape of a hook and appears around 17 days after the injury Fig. From histological analysis, a very thin layer of undifferentiated cells composes the first observed knob.
This structure then disappears, tissues enter in a differentiation state and the process of histogenesis starts.
At later stages between 50 and 60 days usually a complete structure is visible with the restoration of a typical non-injured arm Fig. At this stage both nervous g and muscle elements m become clearly visible and well-organized Fig. Aberrant regeneration. Aberrant regeneration of an arm after lesion in the wild resulted in the formation of three morphologically normal tips. Scale bar 1 cm. Source Dr. Pallial nerve degeneration and regeneration.
An animal before pallial nerve lesion a shows full ability in changing body pattern I and in controlling contraction of respiratory muscles on both sides of the mantle II.
Soon after lesion b the two functions are lost on the denervated side, which becomes completely pale I and flaccid II. Scale bar 0. Despite this loss of functions, the animal appears healthy and active soon after recovery from anesthesia. An increase in self-grooming actions close to the injured area is the only alteration that might occur after lesion Imperadore et al.
Complete functional recovery requires several months, but usually already after 3 to 4 days post surgery the denervated skin undergoes some peculiar changes Sanders and Young First we can observe skin paling due to chromatophore muscles relaxation, as neural control between CNS and periphery is lost Sereni and Young This is followed by dark color waves randomly and quickly crossing the skin of the affected side of the mantle.
Three to five days after injury, the skin on the side of lesion appears, at rest, homogeneously colored and, seven to fourteen days later it is able to match the color pattern of the contralateral side. However, paling immediately returns on the injured side during rapid pattern changes, such as prey attack or escape. This effect cannot be the result of a lack in functional regeneration but it is more likely driven by local effects involving skin photoreceptors Imperadore et al. At the microscopical level, lesions of the nerves induce inflammation followed by the formation of a scar between the two nerve stumps, hemorrhagic areas, and additional cicatricial tissues in the muscles damaged.
These scars are mainly formed by hemocytes, which rush to the site of lesion and invade the nerve stumps. Peripheral stump regeneration is observed after 10—14 days post lesion, it appears initially characterized only by degenerative phenomena, with axons swelling and fragmentation Imperadore et al.
Connective tissue in the nerve appears also to be involved in the process, sealing the cut stumps initially, shaping and driving them toward each other a few days later.
Both, hemocytes and connective tissue actively proliferate at the cut nerve and interestingly neural elements have also been suggested start differentiating as soon as two weeks after lesion Imperadore et al. Arms and mantle skin wounds of various severity and even arm loss are common events experienced by cephalopods in nature. Upon injury, animals can manifest a series of responses going from mild aberration of the body coloration and patterning to severe behavioral modifications.
Body skin appearance have been listed within the potential indicators of health and welfare in cephalopods Fiorito et al. Moreover, it is fundamental to provide a constant assessment of experimental animals undergoing surgical procedures as the occurrence of secondary effects induced by tissue incisions might take place even days after experimentation.
For most of these events, no special treatment has yet been established. The images or other third party material in this chapter are included in the chapter's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the chapter's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.
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