Hemoglobin Loaded Alginate Particles

Over the last few years medical and pharmaceutical industries have shown an increasing interest in alginate, an anionic polysaccharide widely distributed in the cell walls of brown algae. The present work aims at loading Human Hemoglobin (Hb) into alginate particles; the modification of some formulation parameters was carefully investigated by analysing changes on particles size and protein physicochemical properties. Particles were prepared by dropping alginate into an aqueous solution containing Hb and CaCl2, which permits the formation of particles through ionic cross- linking. Hb loaded alginate beads were obtained possessing an average diameter of about 2 mm and a protein loading of about 5%. Physicochemical characterizations showed that the protein maintained its functional ability of reversibly binding oxygen and its quaternary structure once loaded into alginate beads. In a refinement of the first formulation trials, Hb loaded alginate microparticles with diameter around 150 μm were obtained with a protein loading of about 50

Perspectives on polymeric nanostructures for the therapeutic application of antimicrobial peptides

Antimicrobial peptides (AMPs) are a class of promising anti-infective molecules but their therapeutic application is opposed by their poor bioavailability, susceptibility to protease degradation and potential toxicity. The advancement of nanoformulation technologies offers encouraging perspectives for the development of novel therapeutic strategies based on AMPs to treat antibiotic resistant microbial infections. Additionally, the use of polymers endowed per-se with antibacterial properties, stands out as an innovative approach for the development of a new generation of drug delivery systems in which an enhanced antimicrobial action could be obtained by the synergic combination of bioactive polymer matrices and drugs. Herein, the latest AMPs drug delivery research is discussed

Levofloxacin-loaded star poly(ε-caprolactone) scaffolds by additive manufacturing

The employment of a tissue engineering scaffold able to release an antimicrobial agent with a controlled kinetics represents an effective tool for the treatment of infected tissue defects as well as for the prevention of scaffolds implantation-related infectious complications. This research activity was aimed at the development of additively manufactured star poly(ε-caprolactone) (*PCL) scaffolds loaded with levofloxacin, investigated as antimicrobial fluoroquinolone model. For this purpose a computer-aided wet-spinning technique allowing functionalizing the scaffold during the fabrication process was explored. Scaffolds with customized composition, microstructure and anatomical external shape were developed by optimizing the processing parameters. Morphological, thermal and mechanical characterization showed that drug loading did not compromise the fabrication process and the final performance of the scaffolds. The developed *PCL scaffolds showed a sustained in vitro release of the loaded antibiotic for 5 weeks. The proposed computer-aided wet-spinning technique appears well suited for the fabrication of anatomical scaffolds endowed with levofloxacin-releasing properties to be tested in vivo for the regeneration of long bone critical size defects in a rabbit model

Heme oxygenase 1 in the nervous system: Does it favor neuronal cell survival or induce neurodegeneration?

Heme oxygenase 1 (HO-1) up-regulation is recognized as a pivotal mechanism of cell adaptation to stress. Under control of different transcription factors but with a prominent role played by Nrf2, HO-1 induction is crucial also in nervous system response to damage. However, several lines of evidence have highlighted that HO-1 expression is associated to neuronal damage and neurodegeneration especially in Alzheimer\u2019s and Parkinson\u2019s diseases. In this review, we summarize the current literature regarding the role of HO-1 in nervous system pointing out different molecular mechanisms possibly responsible for HO-1 up-regulation in nervous system homeostasis and neurodegeneration

A novel Electrospinning Procedure for the Production of Straight Aligned and Winded Fibers

An electrospinning procedure allowing the spinning of a straight jet of polymer solution was developed. By using proper collector devices, it enables to collect winded and aligned fibers and to prepare polymeric constructs developing along the Z axis. The reported results are expected to provide basic understandings on which parameters are controlling the stability/instability of the process and implement new applications of electrospinning with specific reference to the preparation of well defined three-dimensional structure

Chitosan-Based Nanoparticles Containing Cherry Extract from Prunus avium L. to Improve the Resistance of Endothelial Cells to Oxidative Stress

Cherries are known for their nutraceutical properties, in particular for their antioxidant ability due to their polyphenol content, which causes a reduction of cardiovascular disease (CVD) risk factors. However, once ingested these molecules are degraded in the Gastrointestinal (GI) tract before reaching the blood, which is the action site. The object of the present work is to evaluate the ability of cherry extract (CE), encapsulated in nanoparticles (NPs) based on different chitosan (Ch) derivatives, to promote a protective effect of human umbilical vein endothelial cells (HUVECs) involved in vascular dysfunction against oxidative stress. CE-loaded NPs based on quaternary ammonium chitosan (NP1) and an S-protected thiolated derivative thereof (NP2) were prepared. The mean particle size (NP1 344.9 ± 17.8, NP2 339.9 ± 68.2 nm), the polydispersity index, the encapsulation efficiency (NP1 78.4 ± 4.5, NP2 79.8 ± 0.6%), and the zeta potential (NP1 14.8 ± 0.3, NP2 15.8 ± 0.5 mV) did not appear to be significantly different. Both NP types improved the CE apparent permeation parameters with respect to the control. Conversely, CE-loaded NP2 protected HUVECs from oxidative stress and reduced reactive oxygen species (ROS) production more than CE-loaded NP1 and free CE. In addition to promoting HUVEC resistance, NP2 could be a useful tool to overcome the problem of cherry seasonality

Mutations in the Schmallenberg virus Gc glycoprotein facilitate cellular protein synthesis shutoff and restore pathogenicity of NSs deletion mutants in mice

Serial passage of viruses in cell culture has been traditionally used to attenuate virulence and identify determinants of viral pathogenesis. In a previous study, we found that a strain of Schmallenberg virus (SBV) serially passaged in tissue culture (termed SBVp32) unexpectedly displayed increased pathogenicity in suckling mice compared to wild type SBV. In this study, we mapped the determinants of SBVp32 virulence to the viral genome M segment. SBVp32 virulence is associated with the capacity of this virus to reach higher titers in the brains of experimentally infected suckling mice. We also found that the Gc glycoprotein, encoded by the M segment of SBVp32, facilitates host cell protein shutoff in vitro. Interestingly, while the M segment of SBVp32 is a virulence factor, we found that the S segment of the same virus confers by itself an attenuated phenotype to wild type SBV as has lost the ability to block the innate immune system of the host. Single mutations present in the Gc glycoprotein of SBVp32 are sufficient to compensate both the attenuated phenotype of the SBVp32 S segment and the attenuated phenotype of NSs deletion mutants. Our data also indicate that the SBVp32 M segment does not act as an IFN antagonist. Therefore SBV mutants can retain pathogenicity even when they are unable to fully control the production of IFN by the infected cells. Overall, this study suggests that the viral glycoprotein of orthobunyaviruses can compensate, at least in part, the function of NSs. In addition, we also provide evidence that the induction of total cellular protein shutoff by SBV is determined by multiple viral proteins while the ability to control the production of IFN maps to the NSs protein. Importance The identification of viral determinants of pathogenesis is key to the development of prophylactic and interventions measures. In this study we found that the bunyavirus Gc glycoprotein is a virulence factor. Importantly, we show that mutations in the Gc glycoprotein can restore pathogenicity of attenuated mutants resulting from deletions or mutations in the non-structural protein NSs. Our findings highlight the fact that careful consideration should be taken when designing live attenuated vaccines based on deletions of non-structural proteins since single mutations in the viral glycoproteins appear to revert attenuated mutants to virulent phenotypes

Urinary Metabolites Reveal Hyperinsulinemia and Insulin Resistance in Polycystic Ovarian Syndrome (PCOS)

The identification of insulin resistance and hyperinsulinemia in polycystic ovary syndrome (PCOS) is not a minor issue. The homeostasis model assessment of insulin resistance index (HOMA) is the most used index of IR (Insulin Resistance), validated in overweight and obese patients but not in normal-weight PCOS subjects, who can still present with increased insulin secretion by an oral glucose tolerance test [OGTT]. The evaluation of insulin secretion and resistance represents a still unresolved problem. The aim of this study is to identify a possible yet noninvasive method to properly evaluate the insulin metabolism in young non-diabetic subjects. Girls aged 14–22 years, afferent to the center of Gynecological Diseases in Childhood and Adolescence of Cagliari (Italy), were screened for PCOS. A total of 42 subjects comprised the study group. Hormonal assays, OGTT, transabdominal (TA) or transvaginal (TV) US, and urine collection for 1H-NMR analysis were assayed in the early follicular phase. A 1H-NMR coupled multivariate statistical analysis was performed. The OPLS model indicated that the NMR profile of urine had a good fit and prediction ability for the AUC OGTT with R2 = 0.813. Metabolomics can be a promising tool to the potential identification of biomarkers of an exaggerated insulin response to OGTT and can encourage substantial progress for a more accurate and early diagnosis in PCOS

HO-1 up-regulation: a key point in high-risk neuroblastoma resistance to bortezomib.

AbstractHigh-risk neuroblastoma (NB) is characterized by the development of chemoresistance, and bortezomib (BTZ), a selective inhibitor of proteasome, has been proposed in order to overcome drug resistance. Considering the involvement of the nuclear factor-erythroid-derived 2-like 2 (Nrf2) and heme oxygenase-1 (HO-1) in the antioxidant and detoxifying ability of cancer cells, in this study we have investigated their role in differently aggressive NB cell lines treated with BTZ, focusing on the modulation of HO-1 to improve sensitivity to therapy. We have shown that MYCN amplified HTLA-230 cells were slightly sensitive to BTZ treatment, due to the activation of Nrf2 that led to an impressive up-regulation of HO-1. BTZ-treated HTLA-230 cells down-regulated p53 and up-regulated p21, favoring cell survival. The inhibition of HO-1 activity obtained by Zinc (II) protoprophyrin IX (ZnPPIX) was able to significantly increase the pro-apoptotic effect of BTZ in a p53- and p21-independent way. However, MYCN non-amplified SH-SY5Y cells showed a greater sensitivity to BTZ in relation to their inability to up-regulate HO-1. Therefore, we have shown that HO-1 inhibition improves the sensitivity of aggressive NB to proteasome inhibition-based therapy, suggesting that HO-1 up-regulation can be used as a marker of chemoresistance in NB. These results open up a new scenario in developing a combined therapy to overcome chemoresistance in high-risk neuroblastoma

Resveratrol supplementation during in vitro maturation improves embryo development of prepubertal goat oocytes selected by brilliant cresyl blue staining

This study aimed to investigate the effect of resveratrol supplementation in maturation medium on the developmental ability and bioenergetic\oxidative status of prepubertal goat oocytes selected by brilliant cresyl blue (BCB). Oocytes collected from slaughterhouse-derived ovaries were selected by 13 µM BCB staining and classified as grown BCB+ and growing BCB- oocytes. All oocytes were matured in vitro in our conventional maturation medium and supplemented with 1 µM (BCB+R and BCB-R) and without (Control groups: BCB+C and BCB-C) resveratrol. After 24 h, IVM-oocytes were fertilized with fresh semen and presumptive zygotes were in vitro cultured for 8 days. Oocytes were assessed for blastocyst development and quality, mitochondrial activity and distribution, and levels of GSH, ROS, and ATP. BCB+R (28.3%) oocytes matured with resveratrol presented significantly higher blastocyst development than BCB+C (13.0%) and BCB- groups (BCB-R: 8.3% and BCB-C: 4.7%). Resveratrol improved blastocyst development of BCB-R oocytes at the same rate as BCB+C oocytes. No differences were observed in blastocyst quality among groups. GSH levels were significantly higher in resveratrol groups (BCB+R: 36554.6; BCB-R: 34946.7 pixels/oocyte) than in control groups (BCB+C: 27624.0; BCB-C: 27655.4 pixels/oocyte). No differences were found in mitochondrial activity, ROS level, and ATP content among the groups. Resveratrol-treated oocytes had a higher proportion of clustered active mitochondria in both BCB groups (BCB+R: 73.07%; BCB-R: 79.16%) than control groups (BCB+C: 19.35%; BCB-C: 40%). In conclusion, resveratrol increased blastocyst production from oocytes of prepubertal goats, particularly in better quality oocytes (BCB+)