Dataset Information

Brief Local Application of Progesterone via a Wearable Bioreactor Induces Long-Term Regenerative Response in Adult Xenopus Hindlimb

ABSTRACT: The induction of limb repair depends on signals that initiate regeneration and the successful transmission of those signals in vivo. Here, we characterize the effects of an integrated device-based in vivo delivery of drug compounds in adult Xenopus laevis, which normally regenerate only a cartilaginous spike after limb amputation. A wearable bioreactor containing a silk protein-based hydrogel containing progesterone that was applied to the wound site immediately after hind-limb amputation for 24 hours induced regeneration of flattened paddle-like structures in adult frogs. Molecular assays (ELISA and NGS), Morphometric analysis (soft-tissue patterning), X-ray imaging (bone regrowth), immunofluorescence (cell proliferation, immune response, neuro/vascular tissues), and behavioral data (functional use of regenerates) were used to characterize the differences between the paddle-like structures and the hypomorphic spike observed in untreated animals. Initially, treated animals exhibited an extensive wound epithelium, and increased nerve supply compared to controls. Subsequently, flattened structures with robust bone remodeling were formed, resembling comparable tissues of adult limbs at the early and middle stages of regeneration. The limbs ceased regeneration at the position where the digits usually form. Functional tests revealed that the response to the paddle-like structures was similar to that of uncut limbs. Analysis of the blastema transcriptome identified a number of key genes related to the combined intervention, and also revealed regulated transcripts related to hormonal and neural pathways, representing novel targets for emerging regenerative therapies. Our experiments (1) establish a new model for testing of therapeutic cocktails in vertebrate limb regeneration; (2) identify pro-regenerative activities of progesterone, and (3) provide proof-of-principle of using integrated device-based delivery of small molecule drugs as a viable strategy to induce and maintain a regenerative response.

ORGANISM(S): Xenopus laevis

PROVIDER: GSE118454 | GEO | 2019/01/09

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Salamander limb regeneration is dependent upon tissue interactions that are local to the amputation site. Communication among limb epidermis, peripheral nerves, and mesenchyme coordinate cell migration, cell proliferation, and tissue patterning to generate a blastema, a mass of progenitor cells that forms missing limb structures. An outstanding question is how molecular cross-talk between these tissues gives rise to the regeneration blastema. To identify genes associated with epidermis-nerve-mesenchymal interactions during limb regeneration, we examined histological and transcriptional changes during the first week following injury in the wound epidermis and subjacent cells between three injury types; 1) a flank wound on the side of the animal that will not regenerate a limb, 2) a denervated limb that will not regenerate a limb, and 3) an innervated limb that will regenerate a limb. Early, histological and transcriptional changes were highly similar between the three injury types, presumably because a common wound-healing program is employed across anatomical locations. However, we identified transcripts that were enriched in the limb compared to the flank and are associated with vertebrate limb development. Many of these genes were activated before blastema outgrowth and in situ hybridization showed that some of these genes were expressed in specific tissue types including the epidermis, peripheral nerve, and mesenchyme. We also identified a relatively small group of transcripts that were more highly expressed in innervated limbs versus denervated limbs. These transcripts encode for proteins that are associated with myelination of peripheral nerves, epidermal maintenance, and cell proliferation, suggesting that denervation affects myelinating Schwann cells, epidermal cell function, and proliferation of mesenchymal cells. Overall, our study identifies limb-specific and nerve-dependent genes that are upstream of regenerative growth, and thus promising candidates for the regulation of blastema formation. We used microarray analysis to determine the gene expression changes that take place during limb regeneration, flank wound healing, and an denervated amputated limb. Epidermal tissue and cells adhered to the epidermis were collected as samples. Two harvested samples was pooled for each animal. Four biological replicates were collected from uninjured epidermis (D0) and at 1, 3, and 7 days post injury.

Dataset Information

Brief Local Application of Progesterone via a Wearable Bioreactor Induces Long-Term Regenerative Response in Adult Xenopus Hindlimb

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets