scholarly journals Characterization of Macroporous Polycaprolactone/Silk Fibroin/Gelatin/Ascorbic Acid Composite Scaffolds and In Vivo Results in a Rabbit Model for Meniscus Cartilage Repair

Cartilage ◽  
2021 ◽  
pp. 194760352110354
Author(s):  
Zahra Abpeikar ◽  
Lida Moradi ◽  
Moosa Javdani ◽  
Saeid Kargozar ◽  
Mostafa Soleimannejad ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Antioxidant Capacity ◽  
Silk Fibroin ◽  
Rabbit Model ◽  
Mechanical Tests ◽  
Toxicity Tests ◽  
Self Healing ◽  
Composite Scaffolds ◽  
Meniscus Healing

Objective Meniscus injuries in the inner avascular zone have weak intrinsic self-healing capacity and often progress to osteoarthritis. This study focused on evaluating the effects of polycaprolactone/silk fibroin/gelatin/ascorbic acid (PCL/SF/Gel/AA) composite scaffolds seeded with adipose-derived mesenchymal stem cells (ASCs), in the meniscus repair. Design To this end, composite scaffolds were cross-linked using N-hydroxysuccinimide and 1-ethyl-3-(3-dimethyl-aminopropyl)-1-carbodiimide hydrochloride. Scaffolds were then characterized by scanning electron microscope, mechanical tests, total antioxidant capacity, swelling, and toxicity tests. Results The PCL/SF/Gel/AA scaffolds exhibited suitable mechanical properties. Furthermore, vitamin C rendered them the highest antioxidant capacity. The PCL/SF/Gel/AA scaffolds also showed good biocompatibility and proliferation for chondrocytes. Moreover, the PCL/SF/Gel/AA scaffold seeded with allogeneic ASCs was engrafted in New Zealand rabbits who underwent unilateral punch defect in the medial meniscus of the right knee. After 2 months postimplantation, macroscopic and histologic studies for new meniscus cartilage were performed. Conclusions Our results indicated that the PCL/SF/Gel/AA composite scaffolds seeded with allogeneic ASCs could successfully improve meniscus healing in damaged rabbits.

Prevascularized bladder acellular matrix hydrogel/silk fibroin composite scaffolds promote the regeneration of urethra in a rabbit model

2018 ◽  
Vol 14 (1) ◽  
pp. 015002 ◽  
Author(s):  
Nailong Cao ◽  
Lujie Song ◽  
Wenjing Liu ◽  
Suna Fan ◽  
Dan Jiang ◽  
...  
Keyword(s):  
Silk Fibroin ◽  
Rabbit Model ◽  
Composite Scaffolds ◽  
Acellular Matrix

Influence of pore architectures of silk fibroin/collagen composite scaffolds on the regeneration of osteochondral defects in vivo

2020 ◽  
Vol 8 (3) ◽  
pp. 391-405 ◽  
Author(s):  
Xue Feng ◽  
Peifang Xu ◽  
Tao Shen ◽  
Yihan Zhang ◽  
Juan Ye ◽  
...  
Keyword(s):  
Silk Fibroin ◽  
Osteochondral Defects ◽  
Composite Scaffolds

The aligned scaffolds facilitate migration of endogenous reparative cells, leading to better regeneration of osteochondral defects.

scholarly journals In vivo analysis of a proprietary glass-based adhesive for sternal fixation and stabilization using rabbit and sheep models

2021 ◽  
Vol 32 (5) ◽  
Author(s):  
Cina Mehrvar ◽  
Emily Deignan ◽  
Mark Hurtig ◽  
Gideon Cohen ◽  
Paul Zalzal ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Inflammatory Response ◽  
Rabbit Model ◽  
Median Sternotomy ◽  
Biological Response ◽  
Cadaver Study ◽  
Mechanical Tests ◽  
Sheep Model ◽  
Wire Cerclage

AbstractWire cerclage remains the standard method of care for sternal fixation, following median sternotomy, despite being beset with complications. An emerging treatment option has been to augment the wires with an adhesive. A patented ionomeric glass (mole fraction: SiO2:0.48, ZnO:0.36, CaO:0.12, SrO:0.04) has been used to formulate GPC+, a glass polyalkenoate cement (GPC), by mixing it with poly(acrylic) acid (PAA) and de-ionized water. In a human cadaver study, this material, when applied with wire cerclage, was able to significantly reduce sternal instability. However, the material has yet to be tested in pertinent animal models. Here, after a series of physical and mechanical tests to confirm suitability of the experimental material for implantation, three samples of GPC+ were implanted in either the tibia or femur of three different rabbits, alongside sham defects, for two different time modalities. A further seven samples of GPC+ and one poly(methyl methacrylate) control (PMMA) were implanted in either the tibia or femur of two different sheep. The sheep containing the PMMA was sacrificed at 8 weeks and the other at 16 weeks, to evaluate time dependent biological response. Upon sacrifice, microCT images were acquired and histology slides prepared for analysis. All three GPC+ samples implanted in the rabbit model, for the two time modalities, were characterized by minimal bone resorption along with a mild inflammatory response. Five of the seven GPC+ materials implanted in the sheep model (all three implanted for 8 weeks and two of those implanted for 16 weeks) were associated with mild to moderate immune response, comparable to that observed with PMMA, as well as mild bone resorption. The remaining two GPC + materials (implanted in the sheep model for 16 weeks) exhibited no bone resorption or inflammatory response and appeared to stimulate increased bone density at the implant site. These results suggest that GPC + can be a viable bone adhesive for use in hard tissue applications such as sternal fixation and stabilization.

scholarly journals Mesenchymal Stem Cells in Oriented PLGA/ACECM Composite Scaffolds Enhance Structure-Specific Regeneration of Hyaline Cartilage in a Rabbit Model

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Weimin Guo ◽  
Xifu Zheng ◽  
Weiguo Zhang ◽  
Mingxue Chen ◽  
Zhenyong Wang ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Hyaline Cartilage ◽  
Rabbit Model ◽  
Cartilage Regeneration ◽  
Cartilage Defects ◽  
Composite Scaffolds ◽  
Human Cartilage ◽  
Native Cartilage

Articular cartilage lacks a blood supply and nerves. Hence, articular cartilage regeneration remains a major challenge in orthopedics. Decellularized extracellular matrix- (ECM-) based strategies have recently received particular attention. The structure of native cartilage exhibits complex zonal heterogeneity. Specifically, the development of a tissue-engineered scaffold mimicking the aligned structure of native cartilage would be of great utility in terms of cartilage regeneration. Previously, we fabricated oriented PLGA/ACECM (natural, nanofibrous, articular cartilage ECM) composite scaffolds. In vitro, we found that the scaffolds not only guided seeded cells to proliferate in an aligned manner but also exhibited high biomechanical strength. To detect whether oriented cartilage regeneration was possible in vivo, we used mesenchymal stem cell (MSC)/scaffold constructs to repair cartilage defects. The results showed that cartilage defects could be completely regenerated. Histologically, these became filled with hyaline cartilage and subchondral bone. Moreover, the aligned structure of cartilage was regenerated and was similar to that of native tissue. In conclusion, the MSC/scaffold constructs enhanced the structure-specific regeneration of hyaline cartilage in a rabbit model and may be a promising treatment strategy for the repair of human cartilage defects.

scholarly journals Evaluation of a novel combination of TRAM-34 and ascorbic acid for the treatment of corneal fibrosis in vivo

PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262046
Author(s):  
Allison A. Fuchs ◽  
Praveen K. Balne ◽  
Elizabeth A. Giuliano ◽  
Nishant R. Sinha ◽  
Rajiv R. Mohan
Keyword(s):  
Ascorbic Acid ◽  
Transforming Growth Factor Beta ◽  
Vision Loss ◽  
Transforming Growth Factor ◽  
Corneal Thickness ◽  
Rabbit Model ◽  
Study Endpoint ◽  
Corneal Injury ◽  
Collagen Iii

Corneal injury and aberrant wound healing commonly result in corneal fibrosis and subsequent vision loss. Intermediate-conductance calmodulin/calcium-activated K+ channels (KCa3.1) have been shown to promote fibrosis in non-ocular and ocular tissues via upregulation of transforming growth factor beta (TGFβ). TRAM-34 is a selective inhibitor of KCa3.1 and reduces fibrosis by downregulation of TGFβ-induced transdifferentiation of stromal fibroblasts to myofibroblasts. Ascorbic acid has been demonstrated to be effective in promoting corneal re-epithelialization and reduction of neovascularization via anti-VEGF and anti-MMP mechanisms. This study evaluates tolerability and efficacy of a novel combination of TRAM-34 (25μM) and ascorbic acid (10%) topical treatment for corneal fibrosis using an established in vivo rabbit model and conducting clinical eye examinations. Markers of corneal fibrosis were evaluated in all corneas at study endpoint via histopathology, immunofluorescence, and quantitative real-time PCR. The eyedrop treated eyes showed significantly improved clinical outcomes based on modified McDonald Shadduck scores, reduction of clinical haze on Fantes scores, and reduction of central corneal thickness (CCT). At cellular and molecular levels, eyedrop treatment also significantly reduced expression of alpha smooth muscle actin (α-SMA) mRNA and protein, collagen III mRNA, and fibronectin mRNA compared to non-treated eyes. Our study suggests that a tested new bimodal eyedrop is well tolerated and effectively reduces corneal fibrosis/haze in rabbits in vivo.

scholarly journals In Vitro Antioxidant Capacity of Opuntia spp. Fruits Measured by the LOX-FL Method and its High Sensitivity Towards Betalains

2021 ◽  
Author(s):  
Andrea Gómez-Maqueo ◽  
Mario Soccio ◽  
M. Pilar Cano
Keyword(s):  
Antioxidant Activity ◽  
Ascorbic Acid ◽  
Antioxidant Capacity ◽  
Radical Scavenging ◽  
High Sensitivity ◽  
Biological Mechanisms ◽  
First Time ◽  
Opuntia Spp

AbstractCurrent in vitro methodologies neglect or subestimate the contribution of betalains to antioxidant capacity in foods because they do not reflect their in vivo biological mechanisms. In this study, we assessed the sensibility of the lipoxygenase-fluorescein (LOX-FL) method towards betalains, phenolic compounds and ascorbic acid from Opuntia spp. fruits; and (ii) the antioxidant capacity of peel and pulp extracts from Opuntia ficus-indica L. Mill (var. Fresa, Colorada and Blanco) and Opuntia stricta var. Dillenii; by comparing the LOX-FL method to traditional antioxidant methods (ORAC and TEAC). The spectrophotometric monitoring of the LOX-FL reaction avoided interference caused by betalain pigments. Indicaxanthin and betanin showed high antiperoxidative and radical scavenging mechanisms in the LOX-FL assay. O. stricta var. Dillenii tissues the highest antioxidant capacity which correlated with betanin content. ORAC and TEAC antioxidant methods were less sensible towards betalain antioxidant activity. To our knowledge, this is the first time the LOX-FL antioxidant method has been used on betalains and betalain-rich foods. Graphical Abstract

The Role of Polyphenols in the Modulation of Plasma Non-Enzymatic Antioxidant Capacity (NEAC)

2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito
Keyword(s):  
Antioxidant Capacity ◽  
Dietary Intervention ◽  
Ex Vivo ◽  
The Body ◽  
Dietary Polyphenols ◽  
Enzymatic Antioxidant ◽  
Endogenous Antioxidant

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

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