Preparation and in vitro evaluation of cell adhesion and long-term proliferation of stem cells cultured on silibinin co-embedded PLGA/Collagen electrospun composite nanofibers.

The present research aims to evaluate the efficacy of Silibinin-loaded mesoporous silica nanoparticles (Sil@MSNs) immobilized into polylactic-co-glycolic acid/Collagen (PLGA/Col) nanofibers on the in vitro proliferation of adipose-derived stem cells (ASCs) and cellular senescence. Here, the fabricated electrospun PLGA/Col composite scaffolds were coated with Sil@MSNs and their physicochemical properties were examined by FTIR, FE-SEM, and TGA. The growth, viability and proliferation of ASCs were investigated using various biological assays including PicoGreen, MTT, and RT-PCR after 21 days. The proliferation and adhesion of ASCs were supported by the biological and mechanical characteristics of the Sil@MSNs PLGA/Col composite scaffolds, according to FE- SEM. PicoGreen and cytotoxicity analysis showed an increase in the rate of proliferation and metabolic activity of hADSCs after 14 and 21 days, confirming the initial and controlled release of Sil from nanofibers. Gene expression analysis further confirmed the increased expression of stemness markers as well as hTERT and telomerase in ASCs seeded on Sil@MSNs PLGA/Col nanofibers compared to the control group. Ultimately, the findings of the present study introduced Sil@MSNs PLGA/Col composite scaffolds as an efficient platform for long-term proliferation of ASCs in tissue engineering.

Curcumin-loaded mesoporous silica nanoparticles/nanofiber composites for supporting long-term proliferation and stemness preservation of adipose-derived stem cells.

The present research aims to design and develop a sustained drug release system to support the long-term proliferation of human adipose-derived stem cells (hADSCs) without losing their stemness and entering the cellular senescence through providing typical cell culture conditions. For this purpose, Curcumin-loaded mesoporous silica nanoparticles (CUR@MSNs) incorporated into Poly-ε-Caprolactone/Gelatin (PCL/GEL) hybrid were prepared via blend electrospinning and their impact was evaluated on cell adhesion, viability, proliferation and also the expression of senescence markers and stemness genes after a long-term in vitro culturing. The in vitro release findings proved that the MSNs incorporated into the electrospun nanofibers (NFs) allowed a sustained release of CUR. According to MTT and PicoGreen assays, the significant metabolic activity and proliferation of hADSCs were detected on CUR@MSNs-NFs after 14 and 28 days of incubation. Furthermore, CUR@MSNs-NFs showed better adhesion and spreading of hADSCs compared to other types of NFs. The sustained and prolonged delivery of CUR inhibited the stem cell senescence through the down-regulation of p16INK4A and up-regulation of hTERT. It also led to an increased stemness potency in growing hADSCs on the fibers. These results confirmed that the nanofiber-based sustained drug delivery system might provide a promising approach in designing highly programmable culture platforms to generate sufficient numbers of biologically functional hADSCs for clinical translation.

Development of Emu oil-loaded PCL/collagen bioactive nanofibers for proliferation and stemness preservation of human adipose-derived stem cells: possible application in regenerative medicine.

Adipose tissue-derived stem cells (ASCs) are promising candidate in stem cell therapies, and maintaining their stemness potential is vital to achieve effective treatment. Natural-based scaffolds have been recently attracted increasing attention in nanomedicine and drug delivery. In the present study, a polymeric nanofibrous scaffold was developed based on the polycaprolactone/Collagen (PCL/Coll) containing Emu oil as a bioactive material to induce the proliferation of ASCs, while simultaneously preserving the stemness property of those cells. Fabrication of the electrospun Emu oil-loaded PCL/Coll nanofibers was confirmed by using FE-SEM, FTIR, and tensile test. ASCs were seeded on two types of nanofibers (PCL/Coll and Emu oil-loaded PCL/Coll) and their proliferation, cell cycle progression, and stemness gene expressions were evaluated using MTT, propidium iodide staining, and qPCR during 14 days, respectively. The results indicated that ASCs displayed improved adhesion capacity with the higher rates of bioactivity and proliferation on the Emu oil-loaded nanofibers than the other groups. The proliferation capacity of ASCs on Emu oil-loaded PCL/Coll nanofibers was further confirmed by the cell cycle progression analysis. It was also found that Emu oil-loaded nanofibers significantly up-regulated the expression of stemness markers including sox-2, nanog, oct4, klf4, and c-Myc. The results demonstrated that the nanofibers containing Emu oil can reinforce the cell adhesion and enhance ASCs proliferation while preserving their stemness; therefore, using scaffolds containing natural products may have a great potential to enhance the in vitro expansion capacity of ASCs in the field of stem cell therapy and regenerative medicine.