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Parkinson's disease is the second most common neurodegenerative disease. Currently, there are no curative therapies, with only symptomatic treatment available. One of the principal reasons for the lack of treatments is the problem of delivering drugs to the brain, mainly due to the blood-brain barrier. Hydrogels are presented as ideal platforms for delivering treatments to the brain ranging from small molecules to cell replacement therapies.The potential application of hydrogel-based therapies for Parkinson's disease is addressed. The desirable composition and mechanical properties of these therapies for brain application are discussed, alongside the preclinical research available with hydrogels in Parkinson's disease. Lastly, translational and manufacturing challenges are presented.Parkinson's disease urgently needs novel therapies to delay its progression and for advanced stages, at which conventional therapies fail to control motor symptoms. Neurotrophic factor-loaded hydrogels with stem cells offer one of the most promising therapies. This approach may increase the striatal dopamine content while protecting and promoting the differentiation of stem cells although the generation of synapses between engrafted and host cells remains an issue to overcome. Other challenges to consider are related to the route of administration of hydrogels and their large-scale production, required to accelerate their translation toward the clinic.

The co-administration of glial cell line-derived neurotrophic factor (GDNF) and mesenchymal stem cells (MSCs) in hydrogels (HGs) has emerged as a powerful strategy to enhance the efficient integration of transplanted cells in Parkinson's disease (PD). This strategy could be improved by controlling the cellular microenvironment and biomolecule release and better mimicking the complex properties of the brain tissue. Here, we develop and characterize a drug delivery system for brain repair where MSCs and GDNF are included in a nanoparticle-modified supramolecular guest-host HA HG. In this system, the nanoparticles act as both carriers for the GDNF and active physical crosslinkers of the HG. The multifunctional HG is mechanically compatible with brain tissue and easily injectable. It also protects GDNF from degradation and achieves its controlled release over time. The cytocompatibility studies show that the developed biomaterial provides a friendly environment for MSCs and presents good compatibility with PC12 cells. Finally, using RNA-sequencing (RNA-seq), we investigated how the three-dimensional (3D) environment, provided by the nanostructured HG, impacted the encapsulated cells. The transcriptome analysis supports the beneficial effect of including MSCs in the nanoreinforced HG. An enhancement in the anti-inflammatory effect of MSCs was observed, as well as a differentiation of the MSCs toward a neuron-like cell type. In summary, the suitable strength, excellent self-healing properties, good biocompatibility, and ability to boost MSC regenerative potential make this nanoreinforced HG a good candidate for drug and cell administration to the brain.

Extracellular vesicles (EVs) are nanosized pArtículos with attractive therapeutic potential for cardiac repair. However, low retention and stability after systemic administration limit their clinical translation. As an alternative, the combination of EVs with biomaterial-based hydrogels (HGs) is being investigated to increase their exposure in the myocardium and achieve an optimal therapeutic effect. In this study, we developed and characterized a novel injectable in-situ forming HG based on alginate and collagen as a cardiac delivery vehicle for EVs. Different concentrations of alginate and collagen crosslinked with calcium gluconate were tested. Based on injectability studies, 1% alginate, 0.5 mg/mL collagen and 0.25% calcium gluconate HG was selected as the idoneous combination for cardiac administration using catheter-based systems. Rheological examination revealed that the HG possessed an internal gel structure, weak mechanical properties and low viscosity, facilitating an easy administration. In addition, EVs were successfully incorporated and homogeneously distributed in the HG. After administration in a rat model of myocardial infarction, the HG showed long-term retention in the heart and allowed for a sustained release of EVs for at least 7 days. Thus, the combination of HGs and EVs represents a promising therapeutic strategy for myocardial repair. Besides EVs delivery, the developed HG could represent a useful platform for cardiac delivery of multiple therapeutic agents.

Since the discovery of the beneficial therapeutical effects of extracellular vesicles (EVs), these agents have been attracting great interest as next-generation therapies. EVs are nanosized membrane bodies secreted by all types of cells that mediate cell-cell communication. Although the classification of different subpopulations of EVs can be complex, they are broadly divided into microvesicles and exosomes based on their biogenesis and in large and small EVs based on their size. As this is an emerging field, current investigations are focused on basic aspects such as the more convenient method for EV isolation. In the present paper, we used cardiac progenitor cells (CPCs) to study and compare different cell culture conditions for EV isolation as well as two of the most commonly employed purification methods: ultracentrifugation (UC) and size-exclusion chromatography (SEC). Large and small EVs were separately analysed. We found that serum starvation of cells during the EV collecting period led to a dramatic decrease in EV secretion and major cell death. Regarding the isolation method, our findings suggest that UC and SEC gave similar EV recovery rates. Separation of large and small EV-enriched subpopulations was efficiently achieved with both purification protocols although certain difference in sample heterogeneity was observed. Noteworthy, while calnexin was abundant in large EVs, ALIX and CD63 were mainly found in small EVs. Finally, when the functionality of EVs was assessed on primary culture of adult murine cardiac fibroblasts, we found that EVs were taken up by these cells, which resulted in a pronounced reduction in the proliferative and migratory capacity of the cells. Specifically, a tendency towards a larger effect of SEC-related EVs was observed. No differences could be found between large and small EVs. Altogether, these results contribute to establish the basis for the use of EVs as therapeutic platforms, in particular in regenerative fields.

International audience; Among anticancer nanomedicines, squalenoyl nanocomposites have obtained encouraging outcomes in a great variety of tumors. The prodrug squalenoyl-gemcitabine has been chosen in this study to construct a novel multidrug nanosystem in combination with edelfosine, an alkyl-lysophopholipid with proven anticancer activity. Given their amphiphilic nature, it was hypothesized that both anticancer compounds, with complementary molecular targets, could lead to the formation of a new multitherapy nanomedicine. Nanoassemblies were formulated by the nanoprecipitation method and characterized by dynamic light scattering, transmission electron microscopy and X-ray photoelectron spectroscopy. Because free edelfosine is highly hemolytic, hemolysis experiments were performed using human blood erythrocytes and nanoassemblies efficacy was evaluated in a patient-derived metastatic pediatric osteosarcoma cell line. It was observed that these molecules spontaneously self-assembled as stable and monodisperse nanoassemblies of 51 ± 1 nm in a surfactant/polymer free-aqueous suspension. Compared to squalenoyl-gemcitabine nanoassemblies, the combination of squalenoyl-gemcitabine with edelfosine resulted in smaller particle size and a new supramolecular conformation, with higher stability and drug content, and ameliorated antitumor profile.

Neuroblastoma (NB) is the most common extracranial solid tumor preferentially occurring in preschoolers. Its characteristic aggressiveness and heterogeneous clinical behavior are especially visible in relapsed or refractory cases and hamper therapeutic success. Although the introduction of novel antitumor agents, such as dinutuximab, isotretinoin, irinotecan, or I-131- metaiodobenzylguanidine, has increased survival rates, the situation in high-risk NB remains dismal. Moreover, treatment is particularly aggressive in these patients, leading to short- and long-term toxicities. The extensive research performed using nanotechnology in recent decades has prompted its application as a therapeutic alternative to overcome some of the common limitations of conventional chemotherapy. Nevertheless, the therapeutic role of nanomedicine in pediatric tumors like NB is not fully elucidated, and to date, only albumin-bound paclitaxel nanoparticles have reached clinic stages. In this review, we summarize the current therapeutic strategies for NB with special attention to the use of nanomedicine. We also highlight the preclinical studies on passive and active targeting nanodelivery of therapeutics in experimental NB models.

The combination of polymeric surfactants with different features into mixed micelles give access to properties that may be superior to the single-component micelles. In this work, we investigated synergistic effects in mixtures of D-α-Tocopheryl polyethylene glycol succinate (TPGS) with poloxamines (also known as Tetronic), pH-responsive and thermogelling polyethylene oxide (PEO)-polypropylene oxide (PPO) 4-arm block copolymers. We examined the morphology of the self-assembled micelles of TPGS with Tetronic 1107 (T1107) and 908 (T908) in the presence of naproxen (NA), used as a model drug, and assessed the capacity of the single and mixed micelles to trap the guest, using a combination of small-angle neutron scattering (SANS) and NMR spectroscopy (1D, 2D-NOESY and diffusion NMR), over a range of compositions and temperatures, in the dilute regime and gel state. NA did not interact with T1107 or T908 in their unimer form, but it was incorporated into the hydrophobic core of the micelles above the critical micellar temperature (CMT). In contrast, TPGS dissolved NA at any temperature, mainly in the tocopherol core, with some partitioning in the PEG-shell. The micellar structure was not altered by the presence of NA, except for an expansion of the core size, a result of the preferential accumulation of NA in that compartment. The solubility of the drug in single component micelles increased markedly with temperature, while mixed micelles produced an intermediate enhancement of the solubility between that of TPGS and the poloxamines, which increased at higher TPGS/poloxamine ratios. Micellar hydrogels formed by the packing of the polymeric mixed micelles in a BCC macrolattice, whose structure was not altered by the presence of the drug (at least at 0.2 wt%). The applicability of the drug-loaded gels for topical formulations was explored by transdermal diffusion testing using a synthetic model of skin, showing that the diffusion of NA across the membrane was enhanced by incorporating small amounts of TPGS to the hydrogel, especially with the more hydrophilic T908.

Oral anticancer drugs have earned a seat at the table, as the need for homecare treatment in oncology has increased. Interest in this field is growing as a result of their proven efficacy, lower costs and positive patient uptake. However, the gastrointestinal barrier is still the main obstacle to surmount in chemotherapeutic oral delivery. Anticancer nanomedicines have been proposed to solve this quandary. Among these, lipid nanoparticles are described to be efficiently absorbed while protecting drugs from early degradation in hostile environments. Their intestinal lymphatic tropism or mucoadhesive/penetrative properties give them unique characteristics for oral administration. Considering that chronic cancer cases are increasing over time, it is important to be able to provide treatments with low toxicity and low prices. The challenges, opportunities and therapeutic perspectives of lipid nanoparticles in this area will be discussed in this review, taking into consideration the pre-clinical and clinical progress made in the last decade.

Hypothesis The combination of polymeric surfactants into mixed micelles is expected to improve properties relevant to their use in drug delivery, such as micellar size, gelation, and toxicity. We investigated synergistic effects in mixtures of D-α-Tocopheryl polyethylene glycol succinate (TPGS), an FDA-approved PEGylated derivative of vitamin E, and Tetronic surfactants, pH-responsive and thermogelling polyethylene oxide (PEO)-polypropylene oxide (PPO) 4-arm block copolymers. We hypothesized that mixed micelles would form under specific conditions and provide a handle to tune formulation characteristics. Experiments We examined the morphology of the self-assembled structures in mixtures of TPGS with two Tetronic: T1107 and T908, using a combination of dynamic light scattering (DLS), small-angle neutron scattering (SANS), NMR spectroscopy (NOESY and diffusion NMR) and oscillatory rheology, over a range of compositions, temperatures and pH. Cell viability was assessed in NIH/3T3 fibroblasts. Findings The combination of TPGS with either of the two Tetronic produces spherical core-shell micelles that comprise both surfactants in their structure (mixed micelles). T1107 unimers incorporate into TPGS aggregates below the critical micelle temperature of the poloxamine, while mixed micelles only form under limited conditions with T908. At high concentration/temperature, small proportions of TPGS extend the gel phase, more markedly with T1107, with similar elastic moduli (30–50 kPa) and a BCC crystalline structure. Cell viability of NIH/3T3 fibroblasts grown in the hydrogels increases significantly when the poloxamine gels are doped with TPGS, making the combination of poloxamines and TPGS a promising platform for drug delivery.

Therapeutic perspectives of bone tumors such as osteosarcoma remain restricted due to the inefficacy of current treatments. We propose here the construction of a novel anticancer squalene-based nanomedicine with bone affinity and retention capacity. A squalenyl-hydroxybisphosphonate molecule was synthetized by chemical conjugation of a 1-hydroxyl-1,1-bisphosphonate moiety to the squalene chain. This amphiphilic compound was inserted onto squalenoyl-gemcitabine nanoparticles using the nanoprecipitation method. The co-assembly led to nanoconstructs of 75 nm, with different morphology and colloidal properties. The presence of squalenyl-hydroxybisphosphonate enhanced the nanoparticles binding affinity for hydroxyapatite, a mineral present in the bone. Moreover, the in vitro anticancer activity was preserved when tested in commercial and patient-treated derived pediatric osteosarcoma cells. Further in vivo studies will shed light on the potential of these nanomedicines for the treatment of bone sarcomas., Asociación Española Contra el Cáncer (AECC) (CI14142069BLAN), Fundación Caja Navarra/Obra Social La Caixa and the Asociación de familiares y amigos de pacientes con neuroblastoma (NEN, Nico contra el cáncer) are gratefully acknowledged. CIBER-BBN is an initiative funded by the VI Spanish National R&D&i Plan 2008–2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III (Spain) with assistance from the European Regional Development Fund.

Despite tremendous progress in cell-based therapies for heart repair, many challenges still exist. To enhance the therapeutic potential of cell therapy one approach is the combination of cells with biomaterial delivery vehicles. Here, we developed a biomimetic and biodegradable micro-platform based on polymeric microparticles (MPs) capable of maximizing the therapeutic potential of cardiac progenitor cells (CPCs) and explored its efficacy in a rat model of chronic myocardial infarction. The transplantation of CPCs adhered to MPs within the infarcted myocardial microenvironment improved the long-term engraftment of transplanted cells for up to one month. Furthermore, the enhancement of cardiac cellular retention correlated with an increase in functional recovery. In consonance, better tissue remodeling and vasculogenesis were observed in the animals treated with cells attached to MPs, which presented smaller infarct size, thicker right ventricular free wall, fewer deposition of periostin and greater density of vessels than animals treated with CPCs alone. Finally, we were able to show that part of this beneficial effect was mediated by CPC-derived extracellular vesicles (EVs). Taken together, these findings indicate that the biomimetic microcarriers support stem cell survival and increase cardiac function in chronic myocardial infarction through modulation of cardiac remodeling, vasculogenesis and CPCs-EVs mediated therapeutic effects. The biomimetic microcarriers provide a solution for biomaterial-assisted CPC delivery to the heart. STATEMENT OF SIGNIFICANCE: In this study, we evaluate the possibility of using a biomimetic and biodegradable micro-platform to improve cardiovascular progenitor therapy. The strategy reported herein serves as an injectable scaffold for adherent cells due to their excellent injectability through cardiac catheters, capacity for biomimetic three-dimensional stem cell support and controllable biodegradability. In a rat model of chronic myocardial infarction, the biomimetic microcarriers improved cardiac function, reduced chronic cardiac remodeling and increased vasculogenesis through the paracrine signaling of CPCs. We have also shown that extracellular vesicles derived from CPCs cultured on biomimetic substrates display antifibrotic effects, playing an important role in the therapeutic effects of our tissue-engineered approach. Therefore, biomimetic microcarriers represent a promising and effective strategy for biomaterial-assisted CPC delivery to the heart.

International audience; Despite the interesting chemopreventive, antioxidant and antiangiogenic effects of the natural bioflavonoid genistein (GEN), its low aqueous solubility and bioavailability make it necessary to administer it using a suitable drug carrier system. Nanometric porous Metal-Organic Frameworks (nanoMOFs) are appealing systems for drug delivery. Particularly, the mesoporous MIL-100(Fe) possesses a variety of interesting features related to its composition and structure, which make it an excellent candidate to be used as a drug nanocarrier (highly porous, biocompatible, can be synthetized as homogenous and stable nanoparticles (NPs), etc.). In this study, GEN was entrapped by simple impregnation in MIL-100 NPs achieving a remarkable drug loading (27.1 wt%). A combination of experimental and computing techniques was used to achieve a deep understanding of the encapsulation of GEN in MIL-100 nanoMOF. Subsequently, GEN delivery studies were carried out under simulated physiological conditions, showing on the whole a sustained GEN release for 3 days. Initial pharmacokinetics and biodistribution studies were also carried out upon the oral administration of the GEN@MIL-100 NPs in a mouse model, evidencing a higher bioavailability and showing that this oral nanoformulation appears very promising. To the best of our knowledge, the GEN-loaded MIL-100 will be the first antitumor oral formulation based on nanoMOFs studied in vivo, and paves the way to efficiently deliver nontoxic antitumorals by a convinient oral route. .

Treatment in children with high-risk neuroblastoma remains largely unsuccessful due to the development of metastases and drug resistance. The biological complexity of these tumors and their microenvironment represent one of the many challenges to face. Matrix glycoproteins such as vitronectin act as bridge elements between extracellular matrix and tumor cells and can promote tumor cell spreading. In this study, we established through a clinical cohort and preclinical models that the interaction of vitronectin and its ligands, such as αv integrins, are related to the stiffness of the extracellular matrix in high-risk neuroblastoma. These marked alterations found in the matrix led us to specifically target tumor cells within these altered matrices by employing nanomedicine and combination therapy. Loading the conventional cytotoxic drug etoposide into nanoparticles significantly increased its efficacy in neuroblastoma cells. We noted high synergy between etoposide and cilengitide, a high-affinity cyclic pentapeptide αv integrin antagonist. The results of this study highlight the need to characterize cell-extracellular matrix interactions, to improve patient care in high-risk neuroblastoma., This work was supported by grants from ISCIII and ERDF [PI17/01558] and [PI20/01107]; CIBERONC [contract CB16/12/00484]; Asociación Española contra el Cáncer [FAECC2015/006]; NEN Association [Nico contra el cancer infantil 2017 – PVR00157] and the Neuroblastoma Foundation [PVR00166].

International audience; Glioma is a type of cancer with a very poor prognosis with a survival of around 15 months in the case of glioblastoma multiforme (GBM). In order to advance in personalized medicine, we developed polymeric nanoparticles (PNP) loaded with both SPION (Superparamagnetic Iron Oxide Nanoparticles) and doxorubicin (DOX). The former being used for its potential to accumulate the PNP in the tumor under a strong magnetic field and the later for its therapeutic potential. The emulsion solvent and evaporation method was selected to develop monodisperse PNP with high loading efficiency in both SPION and DOX. Once injected in mice, a significant accumulation of the PNP was observed within the tumoral tissue under static magnetic field as observed by MRI leading to a reduction of tumor growth rate.

Introduction: Neuroblastoma is the most frequent pediatric extracranial solid tumor being responsible for 8-10% of all childhood malignancies. Patient outcome is still a major issue due to neuroblastoma’s heterogeneity and complex tumor biology.1,2 Nanotechnology has been widely studied in cancer treatment with the aim of improving the therapeutic index of chemotherapeutic drugs.3 Among them, etoposide is a podophyllotoxin derivative given to neuroblastoma patients that often presents acute and late toxicities.4 In this study we have designed and characterized etoposide-loaded lipid nanoparticles (ETP-LN) with the aim of improving therapeutics in neuroblastoma management. Methods: ETP-LN were prepared by the hot homogenization followed by ultrasonication method which does not involve the use of any organic solvent.5 Nanoparticles physiochemical properties were characterized (size, homogeneity, surface charge) by dynamic light scattering and drug loading was evaluated by UV-vis and UHPLC-UV methods. Cell viability studies (MTS assay) were performed in multiple human neuroblastoma cell lines: SK-N-BE (2), SK-N-BE(2)C and NGP-A (MYCN-amplified cells) and SH-SY5Y, CHLA-90, NBL-S and SK-N-SH (MCYN-non-amplified cells). Results: Optimized ETP-LN showed a mean particle diameter of 105 ± 3.29 nm with a PDI value of 0.19±0.01, indicating homogenous particle distribution. The surface charge presented a negative zeta potential value of -19.9 ± 4.24 mV. UHPLC-UV showed better reproducibility than the UV-vis method. Nevertheless, both techniques indicated a similar drug loading (4.26 ± 0.18 µg/mg and 4.58 ± 0.60 µg/mg, respectively), corresponding to an encapsulation efficiency of 86.8 + 4.16 %. Preliminary in vitro cell-based cytotoxicity assay revealed that ETP-LN displayed similar IC50 values in the studied cell lines when compared to the free drug, indicating that the encapsulation process did not affect etoposide’s antitumor efficacy. Conclusions: ETP-LN were successfully developed and characterized. Further experiments in vitro and in vivo will be performed to evaluate the therapeutic potential of ETP-LN in neuroblastoma. References: Pastor, E. R. & Mousa, S. A. Current management of neuroblastoma and future direction. Crit. Rev. Oncol. Hematol. 138, 38–43 (2019). Park, J. R., Eggert, A. & Caron, H. Neuroblastoma: Biology, Prognosis, and Treatment. Hematology/Oncology Clinics of North America 24, 65–86 (2010). Rodriguez-Nogales, C., Gonzaiez-Ferna, Y., Aldaz, A., Couvreur, P. & Blanco-Prieto, M. J. Nanomedicines for Pediatric Cancers. (2018). Relling, M. V. et al. Etoposide and antimetabolite pharmacology in patients who develop secondary acute myeloid leukemia. Leukemia 12, 346–352 (1998). Gonzalez-Fernandez, Y., Brown, H. K., Patino-Garcia, A., Heymann, D. & Blanco-Prieto, M. J. Oral administration of edelfosine encapsulated lipid nanoparticles causes regression of lung metastases in pre-clinical models of osteosarcoma. Cancer Lett. 430, 193–200 (2018).

Introduction: Glial cell line-derived neurotrophic factor (GDNF) is a well-establish therapeutic agent for Parkinson’s disease (PD) 1. Its therapeutic potential, being a glycosylated protein, will largely depend on the possibility of administering it with a glycosylation pattern similar to the one present in the native protein 2. Moreover, although several approaches to deliver this protein to the brain have been described 3, a promising strategy would be the use of nanoparticles (NPs) containing GDNF in the dopamine-depleted brain areas. Therefore, the aim of this work was to develop and characterize biodegradable NPs loaded with recombinant GDNF produced in mammalian cells for brain tissue engineering. Methods: GDNF was produced by our group 4. GDNF purity was visualized by SDS-PAGE followed by Coomasie Blue (CB) staining. PC12 cell-based bioassay was used to assess its bioactivity. GDNF was encapsulated in polymeric NPs by multiple emulsion solvent evaporation method using Total Recirculation One Machine System (TROMS). Dynamic light scattering was used to measure the mean particle diameter and polydispersity index (PDI). Encapsulation efficiency was quantified by ELISA. NPs morphology was characterized by scanning electron microscopy (SEM). GDNF in vitro release from NPs disrupted with DMSO was determined by ELISA. Results: GDNF was highly pure. The NPs showed a diameter of 405.5 ± 2.9 nm and a PDI of 0.08 ± 0.03. The encapsulation efficiency was 61.6%. SEM analysis showed spherical particles. GDNF released within the first 24 hours was 19.10 ± 3.5%, followed by a phase of sustained-release with 50.6 ± 3.1% of hGDNF being released within 28 days. PC12 treatment with the hGDNF released from NPs induced outgrowth of neurites in these cells indicating that hGDNF remains bioactive after its nanoencapsulation. Conclusions: GDNF-NPs has been successfully prepared using TROMS, showing a high protein loading and a sustained release. The developed nanosystem has great potential for brain tissue engineering applications. Acknowledgements Torres thanks the Spanish Ministry of Education (Programa FPU (FPU17/01212)) and Government of Navarra (2019_66_NAB9). E. Garbayo is supported by a “Ramon y Cajal Fellowship (RYC2018-025897-I). References E. Garbayo et al, Effective GDNF brain delivery using microspheres-A promising strategy for Parkinson’s disease, J. Control. Release. 135 (2009) . R.A. Barker et al, GDNF and Parkinson’s Disease: Where Next? A Summary from a Recent Workshop, J. Parkinsons. Dis. (2020) . P.V. Torres-Ortega et al, Micro- and nanotechnology approaches to improve Parkinson’s disease therapy, J. Control. Release. 295 (2019). E. Ansorena et al. A simple and efficient method for the production of human glycosylated glial cell line-derived neurotrophic factor using a Semliki Forest virus expression system. Int J Pharm. (2013).

Human glial cell line-derived neurotrophic factor (hGDNF) is the most potent dopaminergic factor described so far, and it is therefore considered a promising drug for Parkinson's disease (PD) treatment. However, the production of therapeutic proteins with a high degree of purity and a specific glycosylation pattern is a major challenge that hinders its commercialization. Although a variety of systems can be used for protein production, only a small number of them are suitable to produce clinical-grade proteins. Specifically, the baby hamster kidney cell line (BHK-21) has shown to be an effective system for the expression of high levels of hGDNF, with appropriate post-translational modifications and protein folding. This system, which is based on the electroporation of BHK-21 cells using a Semliki Forest virus (SFV) as expression vector, induces a strong shut-off of host cell protein synthesis that simplify the purification process. However, SFV vector exhibits a temperature-dependent cytopathic effect on host cells, which could limit hGDNF expression. The aim of this study was to improve the expression and purification of hGDNF using a biphasic temperature cultivation protocol that would decrease the cytopathic effect induced by SFV. Here we show that an increase in the temperature from 33°C to 37°C during the "shut-off period", produced a significant improvement in cell survival and hGDNF expression. In consonance, this protocol led to the production of almost 3-fold more hGDNF when compared to the previously described methods. Therefore, a "recovery period" at 37°C before cells are exposed at 33°C is crucial to maintain cell viability and increase hGDNF expression. The protocol described constitutes an efficient and highly scalable method to produce highly pure hGDNF.

Due to chemoresistance and a high propensity to form lung metastasis, survival rates in pediatric osteosarcoma (OS) are poor. With the aim to improve anticancer activity in pediatric OS, a multidrug nanomedicine was designed using the alkyl-lysophospholipid edelfosine (EF) co-assembled with squalenoyl&ndash, gemcitabine (SQ&ndash, Gem) to form nanoassemblies (NAs) of 50 nm. SQ&ndash, Gem/EF NAs modified the total Gem pool exposure in the blood stream in comparison with SQ&ndash, Gem NAs, which correlated with a better tolerability and a lower toxicity profile after multiple intravenous administrations in mice. For in vivo preclinical assessment in an orthotopic OS tumor model, P1.15 OS cells were intratibially injected in athymic nude mice. SQ&ndash, Gem/EF NAs considerably decreased the primary tumor growth kinetics and reduced the number of lung metastases. Our findings support the candidature of this anticancer nanomedicine as a potential pediatric OS therapy.

Despite the great advances accomplished in the treatment of pediatric cancers, recurrences and metastases still exacerbate prognosis in some aggressive solid tumors such as neuroblastoma and osteosarcoma. In view of the poor efficacy and toxicity of current chemotherapeutic treatments, we propose a single multitherapeutic nanotechnology-based strategy by co-assembling in the same nanodevice two amphiphilic antitumor agents: squalenoyl-gemcitabine and edelfosine. Homogeneous batches of nanoassemblies were easily formulated by the nanoprecipitation method. Their anticancer activity was tested in pediatric cancer cell lines and pharmacokinetic studies were performed in mice. In vitro assays revealed a synergistic effect when gemcitabine was co-administered with edelfosine. Squalenoyl-gemcitabine/edelfosine nanoassemblies were found to be capable of intracellular translocation in patient-derived metastatic pediatric osteosarcoma cells and showed a better antitumor profile than squalenoyl-gemcitabine nanoassemblies alone. The intravenous administration of this combinatorial nanomedicine in mice exhibited a controlled release behavior of gemcitabine and diminished edelfosine plasma peak concentrations. These findings make it a suitable pre-clinical candidate for childhood cancer therapy.

Nanomedicine and drug delivery technologies play a prominent role in modern medicine, facilitating better treatments than conventional drugs. Nanomedicine is being increasingly used to develop new methods of cancer diagnosis and treatment, since this technology can modulate the biodistribution and the target site accumulation of chemotherapeutic drugs, thereby reducing their toxicity. Regenerative medicine provides another area where innovative drug delivery technology is being studied for improved tissue regeneration. Drug delivery systems can protect therapeutic proteins and peptides against degradation in biological environments and deliver them in a controlled manner. Similarly, the combination of drug delivery systems and stem cells can improve their survival, differentiation, and engraftment. The present review summarizes the most important steps carried-out by the group of Prof Blanco-Prieto in nanomedicine and drug delivery technologies. Throughout her scientific career, she has contributed to the area of nanomedicine to improve anticancer therapy. In particular, nanoparticles loaded with edelfosine, doxorubicin, or methotrexate have demonstrated great anticancer activity in preclinical settings of lymphoma, glioma, and pediatric osteosarcoma. In regenerative medicine, a major focus has been the development of drug delivery systems for brain and cardiac repair. In this context, several microparticle-based technologies loaded with biologics have demonstrated efficacy in clinically relevant animal models such as monkeys and pigs. The latest research by this group has shown that drug delivery systems combined with cell therapy can achieve a more complete and potent regenerative response. Cutting-edge areas such as noninvasive intravenous delivery of cardioprotective nanomedicines or extracellular vesicle-based therapies are also being explored. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

A series of fourteen porous Metal–Organic Frameworks (MOFs) with different compositions (Fe, Zn, and Zr; carboxylates or imidazolates) and structures have been successfully synthesised at the nanoscale and fully characterised by XRPD, FTIR, TGA, N2 porosimetry, TEM, DLS and ζ-potential. Their toxicological assessment was performed using two different cell lines: human epithelial cells from foetal cervical carcinoma (HeLa) and murine macrophage cell line (J774). It appears that MOF nanoparticles (NPs) exhibit low cytotoxicity, comparable to those of other commercialised nanoparticulate systems, the less toxic being the Fe carboxylate and the more toxic being the zinc imidazolate NPs. The cytotoxicity values, higher in J774 cells than in HeLa cells, are mainly function of their composition and cell internalisation capacity. Finally, cell uptake of one of the most relevant Fe-MOF-NPs for drug vectorisation has been investigated by confocal microscopy studies, and indicates a faster kinetics of cell penetration within J774 compared to HeLa cells.

Even though substantial advances in understanding glioma pathogenesis have prompted a more rational design of potential therapeutic strategies, glioblastoma multiforme remains an incurable disease with the lowest median overall survival among all malignant brain tumours. Therefore, there is a dire need to find novel drug delivery strategies to improve the current dismal survival outcomes. In this context, nanomedicine offers an appealing alternative as it shows potential to improve brain drug delivery. Accordingly, we here review nanomedicine-based drug delivery strategies tested in orthotopic animal models of glioblastoma intended to improve the efficacy of the drug candidates that are currently used in the clinical setting or that have entered clinical trials for the treatment of glioblastoma multiforme. We also outline the future perspectives of nanotechnology to provide emerging glioblastoma treatment with broad translational clinical potential based on the nanocarriers that have already entered the clinical trials stage for the treatment of malignant glioma.

Chemotherapy protocols for childhood cancers are still problematic due to the high toxicity associated with chemotherapeutic agents and incorrect dosing regimens extrapolated from adults. Nanotechnology has demonstrated significant ability to reduce toxicity of anticancer compounds. Improvement in the therapeutic index of cytostatic drugs makes this strategy an alternative to common chemotherapy in adults. However, the lack of nanomedicines specifically for pediatric cancer care raises a medical conundrum. This review highlights the current state and progress of nanomedicine in pediatric cancer and discusses the real clinical challenges and opportunities.

Nanotechnology is growing quickly, with great advances in the area of nanomedicine. Opening the door to personalized medicine, a considerable number of nanosystems have been synthetized for the diagnosis, treatment and monitoring of diseases. Specifically, gold nanoparticles (AuNPs) have been shown to be good contrast agents. However, they have a limited surface area for the transport of active molecules. In this paper, polymeric nanoparticles encapsulating AuNPs have been synthetized by the double emulsion method (w/o/w) and solvent evaporation technique. This approach opens up the possibility of encapsulating hydrophilic and/or lipophilic thermostable biomolecules. The nanoparticles could be monitored in macrophage cells by simple scanning electron microscopy (SEM). Nevertheless, a micro computed tomography (micro-CT) study revealed that they would not be detected in future in vivo studies. In short, this paper explains the difficulty of obtaining nanovehicles that are trackable from early investigation stages to their clinical use, and discusses the controversy surrounding the concentration of AuNPs needed to obtain enough X-ray attenuation with safe doses.

Heart failure still represents the leading cause of death worldwide. Novel strategies using stem cells and growth factors have been investigated for effective cardiac tissue regeneration and heart function recovery. However, some major challenges limit their translation to the clinic. Recently, biomaterials have emerged as a promising approach to improve delivery and viability of therapeutic cells and proteins for the regeneration of the damaged heart. In particular, hydrogels are considered one of the most promising vehicles. They can be administered through minimally invasive techniques while maintaining all the desirable characteristics of drug delivery systems. This review discusses recent advances made in the field of hydrogels for cardiac tissue regeneration in detail, focusing on the type of hydrogel (conventional, injectable, smart or nano- and micro-gel), the biomaterials used for its manufacture (natural, synthetic or hybrid) and the therapeutic agent encapsulated (stem cells or proteins). We expect that these novel hydrogel-based approaches will open up new possibilities in drug delivery and cell therapies.

Alzheimer's disease (AD) is a neurodegenerative disease with high prevalence in the rapidly growing elderly population in the developing world. The currently FDA approved drugs for the management of symptomatology of AD are marketed mainly as conventional oral medications. Due to their gastrointestinal side effects and lack of brain targeting, these drugs and dosage regiments hinder patient compliance and lead to treatment discontinuation. Nanotechnology-based drug delivery systems (NTDDS) administered by different routes can be considered as promising tools to improve patient compliance and achieve better therapeutic outcomes. Despite extensive research, literature screening revealed that clinical activities involving NTDDS application in research for AD are lagging compared to NTDDS for other diseases such as cancers. The industrial perspectives, processability, and cost/benefit ratio of using NTDDS for AD treatment are usually overlooked. Moreover, active and passive immunization against AD are by far the mostly studied alternative AD therapies because conventional oral drug therapy is not yielding satisfactorily results. NTDDS of approved drugs appear promising to transform this research from 'paper to clinic' and raise hope for AD sufferers and their caretakers. This review summarizes the recent studies conducted on NTDDS for AD treatment, with a primary focus on the industrial perspectives and processability. Additionally, it highlights the ongoing clinical trials for AD management.

Neurodegenerative diseases are now the most debilitating disorders affecting the human population. In recent times, neurodegenerative diseases have become the fourth leading cause of death after heart disease, cancer, and stroke. Neurodegenerative diseases affect the thinking, skilled movements, feelings, cognitive behavior, and memory of a person, resulting in short-term and long-term impairment and disabilities. Neurodegenerative diseases include serious disorders like Alzheimer’s disease, Parkinson’s disease, dementia, and other rare disorders like amyotrophic lateral sclerosis, Huntington’s disease, and prion diseases. Although a century has passed since the discovery of neurodegenerative diseases, there is still a need for more diagnostic approaches and effective cure. The emerging field of nanotechnology promises new techniques to solve some of the challenges in this field. Nanotechnological tools enable drugs to cross the blood–brain barrier and target the site of action in a specific manner. The new generation nanoparticles could also be useful in the treatment of brain diseases. In the present chapter, we explain the way ahead for nanotechnology for the treatment of neurodegenerative disorders.

Parkinson’s disease (PD) is a complex neurodegenerative disorder. It is characterized by a combination of motor and nonmotor symptoms that gradually appear as consequence of the selective loss of dopaminergic neurons in the substantia nigra pars compacta and the presence of Lewy bodies and dystrophic neurites, two abnormal structures composed by misfolded α-synuclein. Recent evidences suggest that the toxicity caused by α-synuclein relies on its oligomerization, which precedes the formation of the large α-synuclein aggregates. Several important contributions have been made in the PD field during recent years. However, an early and accurate diagnosis, together with the availability of disease-modifying therapies, still represents a major unmet need. The emergence of nanotechnology has provided new systems like ultra-sensitive biosensors that are able to detect PD-related biomarkers in complex but more accessible biological fluids, and novel MRI agents for contrast enhancement in imaging applications. Nanotechnology could also revolutionize the PD therapeutic pipeline, which is currently focused on the relief of motor symptoms. To date, the efficacy of nanotechnology in PD treatment has been supported by a large number of preclinical studies that have encapsulated different drugs in a wide range of nanoscale delivery systems such as nanoparticles, liposomes, exosomes, and quantum dots. In this chapter, we provide an overview of recent advances in the application of nanomedicine to both the diagnosis and treatment of PD. The main challenges anticipated, future perspectives, and the possibility of transferring these studies to future clinical trials are also discussed.

With a very poor prognosis and no clear etiology, glioma is the most aggressive cancer in the brain. Thanks to its versatility, nanomedicine is a promising option to overcome the limitations on chemotherapy imposed by the blood brain barrier (BBB). The objective of this paper was to obtain monitored tumor-targeted therapeutic nanoparticles (NPs). To that end, theranostic surfactant-coated polymer poly-Lactic-co-Glycolic Acid (PLGA) nanoplatform encapsulating doxorubicin hydrochloride (DOX) and superparamagnetic iron oxide NPs (SPIONs) were developed. Different non-ionic surfactants known as BBB crossing enhancers (Tween 80, Brij-35, Pluronic F68 or Vitamin E-TPGS) were used to develop 4 types of theranostic nanoplatforms, which were characterized in terms of size and morphology by DLS, TEM and STEM-HAADF analyses. Moreover, the 3-month stability test, the therapeutic efficacy against different glioma cell lines (U87-MG, 9L/LacZ and patient derived-neuronal stem cells) and the Magnetic Resonance Imaging (MRI) relaxivity were studied. Results showed that the synthesised nanoplatforms were stable at 4 °C after their lyophilization, being that of paramount importance to ensure a long-term stability in a future in vivo application. Furthermore, the theranostic nanoplatforms were efficient in the in vitro treatment of glioma cells, proving to have imaging efficacy as MRI contrast agents. Our results show an efficient loading of drugs and good value of the relaxivity. Therefore, the efficient theranostic hybrid nanoplatform developed here could be used to perform MRI-guided delivery of hydrophobic drugs., Edurne Luque-Michel thanks the Government of Navarra for the dissertation research fellowship. Clara Marquina thanks the Spanish Ministry of Economy and Competitiveness for financial support from project MAT2016-78201-P. Authors would like to acknowledge the use of Servicio General de Apoyo a la Investigación-SAI, Universidad de Zaragoza.

Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) are a promising cell source for cardiac repair after myocardial infarction (MI) because they offer several advantages such as potential to remuscularize infarcted tissue, integration in the host myocardium, and paracrine therapeutic effects. However, cell delivery issues have limited their potential application in clinical practice, showing poor survival and engraftment after transplantation. In this work, we hypothesized that the combination of hiPSC-CMs with microparticles (MPs) could enhance long-term cell survival and retention in the heart and consequently improve cardiac repair. CMs were obtained by differentiation of hiPSCs by small-molecule manipulation of the Wnt pathway and adhered to biomimetic poly(lactic-co-glycolic acid) MPs covered with collagen and poly(d-lysine). The potential of the system to support cell survival was analyzed in vitro, demonstrating a 1.70-fold and 1.99-fold increase in cell survival after 1 and 4 days, respectively. The efficacy of the system was tested in a mouse MI model. Interestingly, 2 months after administration, transplanted hiPSC-CMs could be detected in the peri-infarct area. These cells not only maintained the cardiac phenotype but also showed in vivo maturation and signs of electrical coupling. Importantly, cardiac function was significantly improved, which could be attributed to a paracrine effect of cells. These findings suggest that MPs represent an excellent platform for cell delivery in the field of cardiac repair, which could also be translated into an enhancement of the potential of cell-based therapies in other medical applications.

The pharmacodynamic effect and the safety of cyclosporine A lipid nanoparticles (CsA LN) for oral administration were investigated using Sandimmune Neoral® as reference. First, the biocompatibility of the unloaded LN on Caco-2 cells was demonstrated. The pharmacodynamic response and blood levels of CsA were studied in Balb/c mice after 5 and 10 days of daily oral administration equivalent to 5 and 15 mg/kg of CsA in different formulations. The in vivo nephrotoxicity after 15 days of treatment at the high dose was also evaluated. The results showed a significant decrease in lymphocyte count (indicator of immunosuppression) for the CsA LN groups which was not observed with Sandimmune Neoral®. CsA blood levels remained constant over the time after treatment with LN, whereas a proportional increase in drug blood concentration was observed with Sandimmune Neoral®. Therefore, CsA LN exhibited a better pharmacological response along with more predictable pharmacokinetic information, diminishing the risk of toxicity. Moreover, a nephroprotective effect against CsA related toxicity was observed in the histopathological evaluation when LN containing Tween® 80 were administered. Therefore, our preliminary findings suggest LN formulations would be a good alternative for CsA oral delivery, enhancing efficacy and reducing the risk of nephrotoxicity.

Osteosarcoma is the most frequent primary bone tumor in the pediatric age group. Its aggressive local growth pattern and its high propensity to metastasize, mainly to the lungs, give the disease an unfavorable prognosis that has situated this disease as one of the leading causes of pediatric cancer death. Current protocols for osteosarcoma treatment are based on neo-adjuvant (pre-operatory) chemotherapy followed by surgical resection of the tumor and a new phase of adjuvant chemotherapy. Despite the progress that these protocols have made in improving the outcome of the disease, the limited access of drugs to bone tumor and metastases, their indiscriminate distribution in the organism, the high required doses that cause intolerable toxicity and the development of multidrug resistance, still represent a major challenge. Nanotechnology has emerged as a new strategy to successfully address these problems by the development of nanoscaled drug carriers that present the ability to target the drug to the tumor cells, achieving high drug concentrations in the tumor area, while decreasing its presence in healthy tissues and therefore its potential systemic toxicity. This review summarizes the different lipid nanocarriers developed to deliver first and second-line anti-osteosarcoma drugs as well as emerging agents in the treatment of this disease. Moreover, it also discusses the potential of these nanocarriers for the treatment of osteosarcoma.

Osteosarcoma (OS) is the most frequent primary malignant bone tumor in the pediatric population. Current treatments are not able to slow the progression of the disease in patients with metastasis, and their survival rate is still 10–30%. Therefore, new therapeutic approaches are required. In the last decades, lipid nanoparticles (LN) have been widely researched for cancer treatment. These systems are able to carry the cytostatic drug to the affected organs and control the release of their cargo in a prolonged manner. The purpose of the present study was to evaluate edelfosine efficacy in various primary osteosarcoma cell lines and a commercial cell line, and to compare its efficacy to that of methotrexate, a first-line agent traditionally employed in osteosarcoma therapy. We also studied whether the encapsulation of both drugs in LN, edelfosine and methotrexate, affected their in vitro efficacy. Methotrexate and edelfosine LN were successfully developed and characterized. Edelfosine showed higher efficacy treating the metastatic cells when compared to the primary cell lines due to its mechanism of entrance via lipid rafts. This efficacy was improved when edelfosine was administered in LN. Moreover, methotrexate showed higher efficacy in the cells that did not overexpress dihydrofolate reductase, the target enzyme of methotrexate.

Current therapies for Parkinson's disease are symptomatic and unable to regenerate the brain tissue. In recent years, the therapeutic potential of a wide variety of neuroprotective and neuroregenerative molecules such as neurotrophic factors, antioxidants and RNA-based therapeutics has been explored. However, drug delivery to the brain is still a challenge and the therapeutic efficacy of many drugs is limited. In the last decade, micro- and nanoparticles have proved to be powerful tools for the administration of these molecules to the brain, enabling the development of new strategies against Parkinson's disease. The list of encapsulated drugs and the nature of the particles used is long, and numerous studies have been carried out supporting their efficacy in treating this pathology. This review aims to give an overview of the latest advances and emerging frontiers in micro- and nanomedical approaches for repairing dopaminergic neurons. Special emphasis will be placed on offering a new perspective to link these advances with the most relevant clinical trials and with the real possibility of transferring micro- and nanoformulations to industrial scale-up processes. This review is intended as a contribution towards facing the challenges that still exist in the clinical translation of micro- and nanotechnologies to administer therapeutic agents in Parkinson's disease.

Neuregulin-1 loaded poly(lactic-co-glycolic acid) (PLGA) microparticles hold great promise for treating acute myocardial infarction, as they have been proved to recover heart function and induce positive heart remodelling in preclinical studies. More recently, the inflammatory response of the heart after acute myocardial infarction (AMI) has been identified as one of the major mechanisms in cardiac tissue remodelling and repair. However, the connection between neuregulin-1 PLGA microparticles and inflammation is still not well characterised. In the present study we assessed this relationship in a mouse AMI model. First, in vitro evidence indicated that neuregulin-1 PLGA microparticles induced a macrophage polarisation toward a regenerative phenotype (CD206

Polo like kinase 2 (PLK2), a serine/threonine serum inducible kinase, has been proposed to be the major factor responsible for phosphorylating alpha-synuclein (a-syn) at Serine-129 (Ser-129) in Parkinson''s disease (PD). A suitable strategy to gain insights into PLK2’s biological effects might be to increase PLK2 intracellular levels with the aim of reproducing the slow progressive neuronal changes that occur in PD. The goal of this study was to develop and characterize a novel drug delivery system (DDS) for PLK2 cytosolic delivery using Total recirculating one machine system (TROMS), a technique capable of encapsulating fragile molecules while maintaining their native properties. A protocol for nanoparticle (NP) preparation using TROMS was set up. NPs showed a mean diameter of 257 ± 15.61 nm and zeta potential of -16 ± 2 mV, suitable for cell internalization. TEM and SEM images showed individual, spherical, dispersed NPs. The drug entrapment efficacy was 61.86 ± 3.9%. PLK2-NPs were able to enter SH-SY5Y cells and phosphorylate a-syn at Ser-129, demonstrating that the enzyme retained its activity after the NP manufacturing process. This is the first study to develop a DDS for continuous intracellular delivery of PLK2. These promising results indicate that this novel nanotechnology approach could be used to elucidate the biological effects of PLK2 on dopaminergic neurons.

Due to their high porosity and versatile composition and structure, nanoscaled Metal-Organic Frameworks (nanoMOFs) have been recently proposed as novel drug delivery systems, and have been demonstrated to have important capacities and potential for controlled release of different active ingredients. Gentamicin (GM; a broad spectrum aminoglycoside antibiotic indicated in bacterial septicemia therapy) has great therapeutic interest, but the associated bioavailability and toxicity drawbacks accompanying high doses and repeated administration of this free drug make its encapsulation inside new nanocarriers necessary. GM encapsulation within two different porous biofriendly Fe and Zr-carboxylates nanoMOFs was performed by a simple impregnation method, with full characterization of the resulting GM-containing solid using a large panel of techniques (X ray powder diffraction-XRPD, Fourier transform infrared spectroscopy-FTIR, thermogravimetric analysis-TGA, N2 sorption, scanning electron microscopy-SEM, dynamic light scattering-DLS, ζ-potential, fluorescence spectroscopy and molecular simulations). High reproducible encapsulation rates, reaching 600 µg of GM per·mg of formulation, were obtained using the biocompatible mesoporous iron(III) trimesate nanoparticles (NPs) MIL-100(Fe) (MIL: Materials from Institut Lavoisier). In vitro GM delivery studies were also carried out using different oral and intravenous simulated physiological conditions, with complete antibiotic release within 8 h when using protein free media, but lower release rates in the presence of proteins. Furthermore, in vitro toxicity of GM-containing MIL-100(Fe) NPs was investigated on two different cell lines: a monocyte from leukemia (THP-1) and adherent fibroblastoid cells (NIH/3T3). These nanoMOFs had a low cytotoxic profile with IC50 values up to 1 mg·mL−1, ensuring adequate cell proliferation after 24 h. Finally, antibacterial activity studies were carried out on two Gram-positive bacteria and one Gram-negative bacterium: S. aureus, S. epidermidis and P. aeruginosa, respectively. GM-loaded MIL-100(Fe) NPs exhibited the same activity as free GM, confirming that the antibiotic activity of the released GM was conserved.

Osteosarcoma (OS) is the most frequent paediatric bone cancer, responsible for 9% of all cancer-related deaths in children. In this paper, a new strategy based on delivering edelfosine (ET) in lipid nanoparticles (LN) was explored in order to target the primary tumour and eliminate metastases. The in vitro and in vivo efficacy of the free drug, drug loaded into lipid nanoparticles (ET-LN) and doxorubicin (DOX) against osteosarcoma (OS) cells was analysed. ET and ET-LN decreased the growth of OS cells in vitro in a time- and dose-dependent manner. Interestingly, the uptake of ET and ET-LN was lower when OS cells were pre-treated with DOX. In vivo studies revealed that ET and ET-LN slowed down the primary tumour growth in two OS models. However, the combination of both drugs showed no additional anti-tumour effect. Importantly, ET-LN successfully prevented the metastatic spread of OS cells from the primary tumour to the lungs. On the whole, ET-LN are a promising candidate for OS chemotherapy.

Tetronics are X-shaped block-copolymers of polyethylene oxide and polypropylene oxide, which self-assemble into micelles and can undergo a sol-gel transition; these transitions are dependent on temperature, concentration but also pH, due to the central diamine group of the tetrablock. We report the nanoscale morphologies underlying these different phases and the rheology of the systems for a very large, highly hydrophilic block copolymer, Tetronic 908, through the combined use of oscillatory rheology, steadyblock-state and time-resolved fluorescence, small-angle neutron scattering (SANS), dynamic light scattering (DLS) and Fourier transform infrared attenuated total reflectance (FTIR-ATR). At low concentrations, SANS reveal core-shell micelles of ca. 10 nm radius, presenting a dehydrated core and a highly hydrated shell, with relatively small aggregation numbers (Nagg ≈ 13). The micelles are notably affected by the pH, due to the protonation of the central amine spacer at low pH (pH ≈ 2), which shifts micellization to higher temperature, with smaller micelles than at natural pH. In the intermediate concentration regime (10–15%), micelles become smaller (Nagg ≈ 5), and present a higher hydration of the core. In the high concentration regime, Tetronic 908 undergoes a sol-gel transition above a threshold temperature, which is fully inhibited at acidic pH. SANS data from the gel phase reveal a BCC order of tightly packed spheres. Temperature sweeps in oscillatory rheology show a shift of the onset of gelation towards lower temperatures as concentration increases, an increase in the elastic modulus G′ and an expansion of gel region over a larger range of temperatures. SANS and rheology reveal that at pH below the natural pH (ca. 8), gelation is shifted to higher temperatures, but the morphology of the gels is similar, while under highly acidic conditions the gelation is fully suppresed.

A novel biocompatible and bioactive Metal–Organic Framework (BioMOF), named BioMIL-5 (Bioactive Materials from Institut Lavoisier), was hydrothermally synthesized from a Zn2+ salt and azelaic acid, both with interesting antibacterial and dermatological properties. Its structure was determined by high resolution X-ray powder diffraction, and further characterized by infrared spectroscopy, thermogravimetric analysis and elemental analysis. The determination of the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values of BioMIL-5 in Staphylococcus aureus and Staphylococcus epidermidis demonstrated that the antimicrobial activity of the individual components of BioMIL-5 were maintained after its synthesis. Moreover, BioMIL-5 was found to be stable in water and in bacterial culture medium, especially in water, leading to the subsequent progressive release of its active constituents, AzA and Zn2+ ions. Interestingly, this slow active delivery allowed control of the growth of a S. epidermidis suspension over 7 days. The high stability of this material and the maintenance of its antibacterial properties make BioMIL-5 a good candidate for future bioapplications, for skin care and in cosmetics.

Cyclosporine A (CsA) is a well-known immunosuppressive agent used as rescue therapy in severe steroid-refractory ulcerative colitis (UC). However, toxicity issues associated with CsA when administered in its commercially available formulations have been reported in clinical practice. Since nanotechnology has been proposed as a promising strategy to improve safety and efficacy in the treatment of inflammatory bowel disease (IBD), the main purpose of this study was to evaluate the effect of oral administration of CsA-loaded lipid nanoparticles (LN) in the dextran sodium sulfate (DSS)-induced colitis mouse model using Sandimmune Neoral(®) as reference. The results showed that the formulations used did not decrease colon inflammation in terms of myeloperoxidase activity (MPO), tumor necrosis factor (TNF)-α expression, or histological scoring in the acute stage of the disease. However, further studies are needed in order to corroborate the efficacy of these formulations in the chronic phase of the disease.

Glioblastoma multiforme (GBM) is the most common primary brain tumour, and the most aggressive in nature. The prognosis for patients with GBM remains poor, with a median survival time of only 1-2 years. The treatment failure relies on the development of resistance by tumour cells and the difficulty of ensuring that drugs effectively cross the dual blood brain barrier/blood brain tumour barrier. The advanced molecular and genetic knowledge has allowed to identify the mechanisms responsible for temozolomide resistance, which represents the standard of care in GBM, along with surgical resection and radiotherapy. Such resistance has motivated the researchers to investigate new avenues for GBM treatment intended to improve patient survival. In this review, we provide an overview of major obstacles to effective treatment of GBM, encompassing biological barriers, cancer stem cells, DNA repair mechanisms, deregulated signalling pathways and autophagy. New insights and potential therapy approaches for GBM are also discussed, emphasizing localized chemotherapy delivered directly to the brain, immunotherapy, gene therapy and nanoparticle-mediated brain drug delivery.

Tailored nanocarriers have gained huge research focus for brain drug delivery, aimed at combating several neuro-oncological conditions, such as the glioblastoma multiforme (GBM). The progress of knowledge on the pathogenesis of GBM has allowed identifying the major hurdles for efficient treatment, encompassing biological interfaces (blood-brain barrier and blood-brain tumour barrier), specificities of tumour microenvironment, as well as both bulk and glioma stem cell subpopulations. These findings provided new insights into the molecular basis of GBM, being a strong driving force behind development of targeted nanomedicines in this area. Diversified nanoparticles have been designed to target GBM surface markers, overexpressed receptors, aberrant genes and signalling pathways, in addition to contemplating barriers targeting strategies. Among the nanocarriers explored, lipid nanoparticles claim important and unique features, including the versatility in promoting both passive and active drug targeting, making them excellent candidates for brain drug delivery and one of the most appealing to overcome the obstacles of the current GBM treatment.

Cancer is a leading cause of mortality in the world, with osteosarcoma being one of the most common types among children between 1 and 14 years old. Current treatments including preoperative chemotherapy, surgery and postoperative chemotherapy produce several side effects with limited effectiveness. The use of lipid nanoparticles as biodegradable shells for controlled drug delivery shows promise as a more effective and targeted tumor treatment. However, in vitro validation of these vehicles is limited due to fluid stagnation in current techniques, in which nanoparticles sediment onto the bottom of the wells killing the cells by asphyxiation. In the current series of experiments, results obtained with methotrexate-lipid nanoparticles under dynamic assay conditions are presented as a promising alternative to current free drug based therapies. Effects on the viability of the U-2 OS osteosarcoma cell line of recirculation of cell media, free methotrexate and blank and methotrexate containing lipid nanoparticles in a 11 μM concentration were successfully assessed. In addition, several designs for the microfluidic platform used were simulated using COMSOL-Multiphysics, optimized devices were fabricated using soft-lithography and simulated parameters were experimentally validated. Nanoparticles did not sediment to the bottom of the platform, demonstrating the effectiveness of the proposed system. Moreover, encapsulated methotrexate was the most effective treatment, as after 72 h the cell population was reduced nearly 40% while under free methotrexate circulation the cell population doubled. Overall, these results indicate that methotrexate-lipid nanoparticles are a promising targeted therapy for osteosarcoma treatment.

Biomaterial science may offer new approaches to cardiac tissue engineering. Several bioresorbable polymers already possess the characteristics necessary to be administered into a damaged heart for cardiac regeneration after myocardial infarction (MI). This chapter focuses on the principal preclinical studies performed in the past 10 years with natural and synthetic bioresorbable polymers for myocardial repair. Alginate, chitosan, collagen, fibrin, poly(lactic-co-glycolic acid), and polyethylene glycol, among others, have been explored to synthesize cardiac scaffolds such as nanofibers, nano- and microparticles, and hydrogels that have been injected either alone or combined with therapeutic cells and/or proteins into the infarcted heart tissue. Many positive advances, such as cardiac function improvement, infarct size reduction, and increase in neovascularization, have been observed after using such bioresorbable devices. However, although cardiac tissue engineering approaches have been shown to improve heart recovery after MI, there is still no approved treatment available on the market. More research is needed on cardiac tissue engineering strategies to optimize these promising treatments.