Progranulin Promotes the Formation and Development of Capsules Caused by Silicone in Sprague-Dawley Rats

Abstract

Background Silicone implants are currently the most widely used artificial materials in plastic surgery. Capsule formation following implant application is unavoidable. When the capsule is excessively thick and strongly contracted, it can lead to obvious symptoms, clinically known as capsular contracture. Biological factors have always been the focus of research on the capsule formation. As a growth factor, progranulin (PGRN) plays an important regulatory role in wound healing, tissue fibrosis, tumor proliferation and invasion, and inflammation regulation. At present, the research on the capsule mainly involves the regulation of tissue healing and fibrosis under the influence of inflammation. Because PGRN has a regulatory role in these processes, we believe that the study of both can provide a new theoretical basis and intervention sites for monitoring and inhibiting the development of the capsule. Methods In this experiment, the effects of different surgical operations on the content of PGRN in the surgical site and plasma of rats were detected. Sprague-Dawley (SD) rat dermal fibroblasts were co-cultured by recombinant PGRN. The effects of r-PGRN on fibroblasts were detected by 5-ethynyl-2’-deoxyuridine (EdU) assay, wound healing assay and Western blot assay. Finally, the effect of PGRN on capsule formation and contracture was studied by changing the content of PGRN in the prosthesis in rats after operation. Results Surgical trauma and silicone implant increased plasma and local PGRN levels in SD rats. PGRN can activate the TGF-β/SMAD signaling pathway in a dose-dependent manner, thereby promoting fibroblast proliferation, differentiation and migration and inhibiting apoptosis and enhancing cell function, thereby promoting capsule formation and contracture. Conclusion PGRN promotes the formation and contracture of the silicone implant capsule in SD rats by activating the TGF-β/SMAD signaling pathway. This discovery may provide new therapeutic targets and detection indicators.

Polyetheretherketone (PEEK) as a Potential Material for the Repair of Maxillofacial Defect Compared with E-poly(tetrafluoroethylene) (e-PTFE) and Silicone

“…39−41 These smooth capsules may become thicker or thinner over time, causing displacement and deformation of silicone implants under pressure. 42,43 Degradation is a crucial factor when selecting implants for maxillofacial defects. Silicone and PEEK prostheses do not undergo degradation after implantation, whereas e-PTFE implants decrease in volume over time.…”

“…Immunofluorescence showed profuse neovascularization within the connective tissue, with the connections between the implants and the surrounding tissue restricting implant movement, suggesting that e-PTFE and PEEK prostheses will have a low probability of migration after implantation. By contrast, silicone had a smooth surface and poor histocompatibility, limiting integration with the surrounding tissue but instead forming a fibrotic peri-prosthetic capsule. − These smooth capsules may become thicker or thinner over time, causing displacement and deformation of silicone implants under pressure. , …”