Theodora Chlapanidas

Adipose-Derived Stem Cell Therapy for Intervertebral Disc Regeneration: An In Vitro Reconstructed Tissue in Alginate Capsules

The degenerative pathologies of the intervertebral disc have a remarkable social impact in the industrialized countries and can provide serious disabilities in the population. The current treatment consists of conservative treatments (such as symptomatic pharmacological therapies and physiokinetic therapy) and surgical treatments (intervertebral fusion, total disc replacement, nucleus pulposus (NP) replacement, or surgical exeresis). Recent advances in cell therapy foresee the possibility of regenerating the damaged disc; the autologous disc tissue can be withdrawn, in vitro regenerated, and re-implanted. The aim of this work was to verify whether autologous adipose-derived adult stem cells can improve the quality of an in vitro reconstructed nucleus pulposus tissue. A three-dimensional (3D) co-culture of NP cells and adipose tissue non-adipocyte fraction cells (nAFs) was assessed in a previously developed alginate 3D culture system following the good manufacturing practice guidelines to ensure patient safety for clinical studies. Morphological investigation of cultured and co-cultured cells was performed using transmission electron microscopy and immunofluorescence for collagen type I, aggrecan, CD90, CD34, and vimentin. Results indicate that co-culture of NP and nAFs improves the quality of the in vitro reconstructed tissue in term of extracellular matrix production and 3D cell organization. Technological resources are available for NP cell encapsulation intended for regenerating the intervertebral disc.

Sericins exhibit ROS-scavenging, anti-tyrosinase, anti-elastase, and in vitro immunomodulatory activities.

Some biological properties of Bombyx mori sericins from twenty strains were investigated, fourteen fed with artificial diet, two with fresh mulberry leaves and four with both diets. Sericin exhibited ROS-scavenging, anti-tyrosinase and anti-elastase properties, the strain significantly influenced these properties, while diet only influenced the anti-tyrosinase activity. Sericins were clustered into 5 groups and one sericin from each group was further studied: sericins showed anti-proliferative activity on in vitro stimulated peripheral blood mononuclear cells; some strains decreased in vitro secretion of IFNγ, while no effects were observed on TNFα and IL10 release. Therefore, a mixture of sericins extracted from the most promising strains may be useful for dermatological and cosmetic use.

Inulin-d-α-Tocopherol Succinate (INVITE) Nanomicelles as a Platform for Effective Intravenous Administration of Curcumin

The aim of this work was to evaluate the potential of INVITE-based nanomicelles, an amphiphilic polymer constituted by inulin (INU) and vitamin E (VITE), as a platform for improving the biopharmaceutical properties of hydrophobic drugs. For this purpose, curcumin was selected as a model and curcumin-INVITE nanomicelles were prepared. This drug delivery system was characterized both in vitro for what concerns the physicochemical properties, blood compatibility, and cellular uptake, and in vivo for the evaluation of the pharmacokinetic profile. It was found that these nanomicelles released curcumin in a controlled manner, and they were able to penetrate cellular membrane. Moreover, they showed an improved pharmacokinetic profile after intravenous administration. In conclusion, INVITE micelles might constitute promising nanocarriers for improving the biopharmaceutical performance of hydrophobic drugs.

Semen controlled-release capsules allow a single artificial insemination in sows

Controlled-release capsules containing boar spermatozoa were developed to extend the preservation time of spermatozoa and maximize the efficiency of a single artificial insemination. A large trial (4245 sows) was performed with these capsules using double/triple conventional artificial insemination as a control. The effect of treatment on pregnancy diagnosis, delivery, and born piglets was investigated, with allowance being made for considering season, spermatozoa amount, and the weaning-to-estrus interval as confounding variables. The same pregnancy rate and prolificacy were obtained by two insemination techniques, and a higher parturition frequency was reached with capsules. The reproductive performance in pigs has therefore been optimized by a single instrumental insemination with controlled-release capsules.

TNF-α Blocker Effect of Naringenin-Loaded Sericin Microparticles that Are Potentially Useful in the Treatment of Psoriasis

This study aims to evaluate the effect of combined use of the racemic flavanone Naringenin (NRG) and the protein sericin as TNF-α blockers. Sericin (SMs) and (R/S) NRG-loaded Sericin (SNRGMs) microparticles were prepared by spray-drying, characterized in terms of morphology and particle size distribution, and encapsulation efficiency was determined. Concerning morphology and particle size distribution of microparticles, results indicated that they were not affected by the presence of NRG. The encapsulation efficiency was almost quantitative (93%), thus proving that sericin can be advantageously loaded with (R/S) NRG. Biological evaluation of (R/S) NRG, SMs and SNRGMs was then performed in lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells (hPBMC). SNRGMs resulted cytotoxic at the higher dose used (200 μg/mL) and the effect was greater than (R/S) NRG alone. Moreover, even if sericin alone was not effective in suppressing LPS-induced serum TNF-α levels, SNRGMs loaded with 9.3% of (R/S) NRG were significantly more potent than (R/S) NRG alone. In summary, this study provides the proof of concept that sericin-based microspheres loaded with TNF-α-blockers could contribute to the down regulation of the cytokine and represents the starting point for the development of new topical formulations for the treatment of middle-stage psoriasis.

Stem cell-extracellular vesicles as drug delivery systems: New frontiers for silk/curcumin nanoparticles

The aim of this work was to develop a novel carrier-in-carrier system based on stem cell-extracellular vesicles loaded of silk/curcumin nanoparticles by endogenous technique. Silk nanoparticles were produced by desolvation method and curcumin has been selected as drug model because of its limited water solubility and poor bioavailability. Nanoparticles were stable, with spherical geometry, 100nm in average diameter and the drug content reached about 30%. Cellular uptake studies, performed on mesenchymal stem cells (MSCs), showed the accumulation of nanoparticles in the cytosol around the nuclear membrane, without cytotoxic effects. Finally, MSCs were able to release extracellular vesicles entrapping silk/curcumin nanoparticles. This combined biological-technological approach represents a novel class of nanosystems, combining beneficial effects of both regenerative cell therapies and pharmaceutical nanomedicine, avoiding the use of viable replicating stem cells.

Sponge-Like Dressings Based on the Association of Chitosan and Sericin for the Treatment of Chronic Skin Ulcers. I. Design of Experiments–Assisted Development

The aim of the present work was the development of sponge-like dressings based on chitosan glutamate (high molecular weight) and sericin for the treatment of chronic skin ulcers. Dressings were prepared by freeze-drying and glycine was added as cryoprotectant agent. Dressing development was assisted by design of experiments, using a simplex centroid design. Mechanical resistance, hydration propensity, viscous, and viscoelasticity properties of dressings were considered as response variables. The superimposition of the contour plots, calculated by the best fit model for each response variable, permitted to individuate a region of the factor space where the dressing of optimized quantitative composition was chosen. Such a dressing was able to absorb high amount of phosphate-buffered saline forming a gel characterized by rheological properties enabling both a lubricant and a protective effect. The optimized formulation was characterized by optimal mechanical properties and by cell proliferation and antioxidant activity on human fibroblast cell line.

A dry powder formulation from silk fibroin microspheres as a topical auto-gelling device

Abstract With the aim of establishing the formulation of a new hydrophilic auto-gelling medical device for biomedical applications, fibroin-based microspheres were prepared. The proposed microspheres were produced by a cost-effective and industrially scalable technique, such as the spray-drying. Spray-dried silk fibroin microspheres were obtained and the effects of different hydrophilic polymer on the process yield, microsphere morphology and conformation transition of fibroin were evaluated. The final auto-gelling formulations were obtained by adding calcium gluconate (as a calcium source for alginate crosslinking) to the prepared microspheres and tested by an in vitro gelling test. This study showed that the combination of fibroin with sodium alginate and poloxamer produced the most promising auto-gelling formulation for specific biomedical applications, such as the treatment of pressure ulcers.

Inulin based micelles loaded with curcumin or celecoxib with effective anti-angiogenic activity

Curcumin (CUR) and celecoxib (CLX) are two highly hydrophobic drugs which show bioavailability problems due to their poor aqueous solubility. The aim of this study was to encapsulate each of these drugs in micelles based on biodegradable and amphiphilic polymers to investigate their anti-angiogenesis activity. Here we use an amphiphilic polymer, based on two natural substances from renewable resources (Inulin and Vitamin E, INVITE), as a self-assembling system for the drug delivery of CUR and CLX. By the in vivo assay of chick embryo chorioallantoic membrane (CAM) it was assessed that both INVITE-CUR and INVITE-CLX micelles possess remarkable anti-angiogenic activity, while the INVITE micelles alone resulted intrinsically pro-angiogenic. Furthermore, it has been shown that encapsulation of CUR and CLX in INVITE micelles enhances of several magnitudes the water-solubility of CUR and CLX (14·10(5) and 3·10(2) times for CUR and CLX, respectively). These results may have interesting implications not only in anticancer or diabetic maculopathy therapy based on the anti-angiogenesis strategy but also for regenerative medicine where over-production of new vessels is required.

Encapsulation of sex sorted boar semen: Sperm membrane status and oocyte penetration parameters

Although sorted semen is experimentally used for artificial, intrauterine, and intratubal insemination and in vitro fertilization, its commercial application in swine species is still far from a reality. This is because of the low sort rate and the large number of sperm required for routine artificial insemination in the pig, compared with other production animals, and the greater susceptibility of porcine spermatozoa to stress induced by the different sex sorting steps and the postsorting handling protocols. The encapsulation technology could overcome this limitation in vivo, protecting and allowing the slow release of low-dose sorted semen. The aim of this work was to evaluate the impact of the encapsulation process on viability, acrosome integrity, and on the in vitro fertilizing potential of sorted boar semen. Our results indicate that the encapsulation technique does not damage boar sorted semen; in fact, during a 72-hour storage, no differences were observed between liquid-stored sorted semen and encapsulated sorted semen in terms of plasma membrane (39.98 ± 14.38% vs. 44.32 ± 11.72%, respectively) and acrosome integrity (74.32 ± 12.17% vs. 66.07 ± 10.83%, respectively). Encapsulated sorted spermatozoa presented a lower penetration potential than nonencapsulated ones (47.02% vs. 24.57%, respectively, P < 0.0001), and a significant reduction of polyspermic fertilization (60.76% vs. 36.43%, respectively, polyspermic ova/total ova; P < 0.0001). However, no difference (P > 0.05) was observed in terms of total efficiency of fertilization expressed as normospermic oocytes/total oocytes (18.45% vs. 15.43% for sorted diluted and sorted encapsulated semen, respectively). The encapsulation could be an alternative method of storing of pig sex sorted spermatozoa and is potentially a promising technique in order to optimize the use of low dose of sexed spermatozoa in vivo.