Biocomposite nanofibrous strategies for the controlled release of biomolecules for skin tissue regeneration

Nanotechnology and tissue engineering have enabled engineering of nanostructured strategies to meet the current challenges in skin tissue regeneration. Electrospinning technology creates porous nanofibrous scaffolds to mimic extracellular matrix of the native tissues. The present study was performed to gain some insights into the applications of poly(L-lactic acid)-co-poly-(ε-caprolactone) (PLACL)/silk fibroin (SF)/vitamin E (VE)/curcumin (Cur) nanofibrous scaffolds and to assess their potential for being used as substrates for the culture of human dermal fibroblasts for skin tissue engineering. PLACL/SF/VE/Cur nanofibrous scaffolds were fabricated by electrospinning and characterized by fiber morphology, membrane porosity, wettability, mechanical strength, and chemical properties by Fourier transform infrared (FTIR) analysis. Human dermal fibroblasts were cultured on these scaffolds, and the cell scaffold interactions were analyzed by cell proliferation, cell morphology, secretion of collagen, expression of F-actin, and 5-chloromethylfluorescein diacetate (CMFDA) dye. The electrospun nanofiber diameter was obtained between 198±4 nm and 332±13 nm for PLACL, PLACL/SF, PLACL/SF/VE, and PLACL/SF/VE/Cur nanofibrous scaffolds. FTIR analysis showed the presence of the amide groups I, II, and III, and a porosity of up to 92% obtained on these nanofibrous scaffolds. The results showed that the fibroblast proliferation, cell morphology, F-actin, CMFDA dye expression, and secretion of collagen were significantly increased in PLACL/SF/VE/Cur when compared to PLACL nanofibrous scaffolds. The accessibility of human dermal fibroblasts cultured on PLACL/SF/VE/Cur nanofibrous scaffolds proved to be a potential scaffold for skin tissue regeneration.Published versio

Hydroxyapatite-intertwined hybrid nanofibres for the mineralization of osteoblasts

Advances in tissue engineering have enabled the development of bioactive composite materials to generate biomimetic nanofibrous scaffolds for bone replacement therapies. Polymeric biocomposite nanofibrous scaffolds architecturally mimic the native extracellular matrix (ECM), delivering tremendous regenerative potential for bone tissue engineering. In the present study, biocompatible poly(l-lactic acid)-co-poly(ε-caprolactone)-silk fibroin-hydroxyapatite-hyaluronic acid (PLACL-SF-HaP-HA) nanofibrous scaffolds were fabricated by electrospinning to mimic the native ECM. The developed nanofibrous scaffolds were characterized in terms of fibre morphology, functional group, hydrophilicity and mechanical strength, using SEM, FTIR, contact angle and tabletop tensile-tester, respectively. The nanofibrous scaffolds showed a higher level of pore size and increased porosity of up to 95% for the exchange of nutrients and metabolic wastes. The fibre diameters obtained were in the range of around 255 ± 13.4-789 ± 22.41 nm. Osteoblasts cultured on PLACL-SF-HaP-HA showed a significantly (p < 0.001) higher level of proliferation (53%) and increased osteogenic differentiation and mineralization (63%) for the inclusion of bioactive molecules SF-HA. Energy-dispersive X-ray analysis (EDX) data proved that the presence of calcium and phosphorous in PLACL-SF-HaP-HA nanofibrous scaffolds was greater than in the other nanofibrous scaffolds with cultured osteoblasts. The obtained results for functionalized PLACL-SF-HaP-HA nanofibrous scaffolds proved them to be a potential biocomposite for bone tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd

Value of soluble Urokinase plasminogen activator receptor over age as a biomarker of impaired myocardial relaxation

Background: SuPAR is a biomarker that reflects the level of immune activation. As inflammation plays an important role in the ageing process of the cardiovascular system, we hypothesized that suPAR might be a useful predictive biomarker of the ageing heart. Methods: We performed conventional and tissue Doppler echocardiography and measured plasma suPAR levels. Results: We studied community adults (n=120, 37.5% female) (mean age: 70.3±9.3 years) without known cardiovascular disease (CVD). Participants with impaired myocardial relaxation were older (84% vs 59% were aged ≥71 years, p=0.002), with more diabetes mellitus (27% vs 11%, p=0.034). SuPAR levels were higher among participants with impaired myocardial relaxation (3.9 ng/ml vs 3.0 ng/ml, p=0.015). At the univariate level, older age (OR 3.6; 95%CI 1.6, 8.5; p=0.003), diabetes mellitus (OR 3.04; 95%CI 1.1, 8.8; p=0.04), systolic blood pressure (OR 1.03; 95%CI 1.001, 1.1; p=0.041) and suPAR levels ≥3.00ng/ml (OR 3.4; 95%CI 1.16, 7.4; p=0.002) were associated with impaired myocardial relaxation. In multivariable regression analysis, only older age (OR 2.8; 95%CI 1.1, 6.7; p=0.026) and suPAR (OR 2.7; 95%CI 1.2, 6.1; p=0.018) remained independently associated with impaired myocardial relaxation. Receiver operating characteristics (ROC) curve analysis revealed an area under the curve (AUC) value of 0.63 (95% CI 0.54, 0.71) for model that included age alone. Addition of suPAR significantly increased AUC value to 0.70 (95%CI 0.60, 0.79), which was significantly larger than the model with age alone (p=0.016). Conclusion: We demonstrate additional ability of suPAR, over age, to predict impaired myocardial relaxation.ASTAR (Agency for Sci., Tech. and Research, S’pore)NMRC (Natl Medical Research Council, S’pore)Published versio

Value of soluble Urokinase plasminogen activator receptor over age as a biomarker of impaired myocardial relaxation

Abstract Background SuPAR is a biomarker that reflects the level of immune activation. As inflammation plays an important role in the ageing process of the cardiovascular system, we hypothesized that suPAR might be a useful predictive biomarker of the ageing heart. Methods We performed conventional and tissue Doppler echocardiography and measured plasma suPAR levels. Results We studied community adults (n=120, 37.5% female) (mean age: 70.3±9.3 years) without known cardiovascular disease (CVD). Participants with impaired myocardial relaxation were older (84% vs 59% were aged ≥71 years, p=0.002), with more diabetes mellitus (27% vs 11%, p=0.034). SuPAR levels were higher among participants with impaired myocardial relaxation (3.9 ng/ml vs 3.0 ng/ml, p=0.015). At the univariate level, older age (OR 3.6; 95%CI 1.6, 8.5; p=0.003), diabetes mellitus (OR 3.04; 95%CI 1.1, 8.8; p=0.04), systolic blood pressure (OR 1.03; 95%CI 1.001, 1.1; p=0.041) and suPAR levels ≥3.00ng/ml (OR 3.4; 95%CI 1.16, 7.4; p=0.002) were associated with impaired myocardial relaxation. In multivariable regression analysis, only older age (OR 2.8; 95%CI 1.1, 6.7; p=0.026) and suPAR (OR 2.7; 95%CI 1.2, 6.1; p=0.018) remained independently associated with impaired myocardial relaxation. Receiver operating characteristics (ROC) curve analysis revealed an area under the curve (AUC) value of 0.63 (95% CI 0.54, 0.71) for model that included age alone. Addition of suPAR significantly increased AUC value to 0.70 (95%CI 0.60, 0.79), which was significantly larger than the model with age alone (p=0.016). Conclusion We demonstrate additional ability of suPAR, over age, to predict impaired myocardial relaxation. Trial registration ClinicalTrials.gov Identifier: NCT02791139 (Registered May 31, 2016)