Osteoblasts migration, attachment and human bone marrow-mesenchymal stem cells osteogenic differentiation towards surface engineered and growth factors conjugated poly(lactic acid) microspheres.

Recently, surface engineered biomaterials through surface modification are extensively investigated due to its potential to enhance cellular homing and migration which contributes to a successful drug delivery process. This study is focused on osteoblasts response towards surface engineered using a simple sodium hydroxide (NaOH) hydrolysis and growth factors conjugated poly(lactic acid) (PLA) microspheres. In this study, evaluation of the relationship of NaOH concentration with the molecular weight changes and surface morphology of PLA microspheres specifically wall thickness and porosity prior to in vitro studies was investigated. NaOH hydrolysis of 0.1 M, 0.3 M and 0.5 M were done to introduce hydrophilicity on the PLA prior to conjugation with basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF). Morphology changes showed that higher concentration of NaOH could accelerate the hydrolysis process as the highest wall thickness was observed at 0.5 M NaOH with ~3.52 µm. All surface modified and growth factors conjugated PLA microspheres wells enhanced the migration of the cells during wound healing process as wound closure was 100% after 3 days of treatment. Increase in hydrophilicity of the surface engineered and growth factors conjugated PLA microspheres provides favorable surface for cellular attachment of osteoblast, which was reflected by positive DAPI staining of the cells' nucleus. Surface modified and growth factors conjugated PLA microspheres were also able to enhance the capability of the PLA in facilitating the differentiation process of mesenchymal stem cells (MSCs) into osteogenic lineage since only positive stain was observed on surface engineered and growth factors conjugated PLA microspheres. These results indicated that the surface engineered and growth factors conjugated PLA microspheres were non-toxic for biological environments and the improved hydrophilicity made them a potential candidate as a drug delivery vehicle as the cells can adhere, attach and proliferate inside it.

Aerosolised Mesenchymal Stem Cells Expressing Angiopoietin-1 Enhances Airway Repair.

BACKGROUND: The aim of this study was to investigate the effects of MSCs and MSC-expressing ANGPT1 (MSC-pANGPT1) treatment via aerosolisation in alleviating the asthma-related airway inflammation in the rabbit model. METHODS: Rabbits were sensitised and challenged with both intraperitoneal injection and inhalation of ovalbumin (Ova). MSCs and MSC-pANGPT1 cells were aerosolised into rabbit lungs using the MicroSprayer® Aerosolizer Model IA-1B 48 h after injury. The post mortem was performed 3 days following cell delivery. Histopathological assessments of the lung tissues and inflammatory response were quantitatively scored following treatments. RESULT(S): Administration of aerosolised MSCs and MSC-pANGPT1 were significantly reduced inflammation of the airways (p < 0.001), as reflected by improved of structural changes such as thickness of the basement membrane, epithelium, mucosa and sub-mucosa regions. The airway inflammation score of both treatment groups revealed a significant reduction of inflammation and granulocyte infiltration at the peribronchiale and perivascular regions (p < 0.05). Administration of aerosolised MSCs alone was resulted in significant reduction in the levels of pro-inflammatory genes (IL-4 and TGF-ß) while treatment with aerosolised MSC-pANGPT1 led to further reduction of various pro-inflammatory genes to the base-line values (IL4, TNF, MMP9 and TGF-ß). Treatment with both aerosolised MSCs and MSC-pANGPT1 cells was also alleviated the number of airway inflammatory cells in the bronchoalveolar lavage (BAL) fluid and goblet cell hyperplasia. CONCLUSION(S): Our findings suggest that treatment with MSCs alone attenuated airway inflammation and structural changes of the airway. Treatment with MSC-pANGPT1 provided an additional effect in reducing the expression levels of various pro-inflammatory genes. Both of these treatment enhancing airway repair and therefore may provide a basis for the development of an innovative approach for the treatment and prevention of airway inflammatory diseases.

Aerosol-based airway epithelial cell delivery improves airway regeneration and repair.

Aerosol-based cell therapy has emerged as a novel and promising therapeutic strategy for treating lung diseases. The goal of this study was to determine the safety and efficacy of aerosol-based airway epithelial cell (AEC) delivery in the setting of acute lung injury induced by tracheal brushing in rabbit. Twenty-four hours following injury, exogenous rabbit AECs were labelled with bromodeoxyuridine and aerosolized using the MicroSprayer® Aerosolizer into the injured airway. Histopathological assessments of the injury in the trachea and lungs were quantitatively scored (1 and 5 days after cell delivery). The aerosol-based AEC delivery appeared to be a safe procedure, as cellular rejection and complications in the liver and spleen were not detected. Airway injury initiated by tracheal brushing resulted in disruption of the tracheal epithelium as well as morphological damage in the lungs that is consistent with acute lung injury. Lung injury scores were reduced following 5 days after AEC delivery (AEC-treated, 0.25  ± â€…0.06 vs. untreated, 0.53  ± â€…0.05, P  < â€…0.01), and rapid clearance of haemorrhage, proteinaceous debris and hyaline membranes occurred. In the trachea, AEC delivery led to an upsurge in epithelium regeneration and repair. Re-epithelialization was significantly increased 5 days after treatment (AEC-treated, 91.07  ± â€…2.37% vs. untreated, 62.99  ± â€…7.39%, P  < â€…0.01). Our results indicate that AEC delivery helps in the regeneration and repair of the respiratory airway, including the lungs, following acute insults. These findings suggest that aerosol-based AEC delivery can be a valuable tool for future therapy to treat acute lung injury. Copyright © 2017 John Wiley & Sons, Ltd.

An analysis of genetic association in opioid dependence susceptibility.

WHAT IS KNOWN: Drug addiction is a novelty-seeking personality trait that is associated with the candidate genes OPRD1 (opioid delta receptors), OPRK1 (opioid kappa receptors) and PDYN (prodynorphin). However, associations between single nucleotide polymorphisms (SNPs) rs1042114 (80G>T) of the OPRD1 gene, rs702764 (843 A>G) of the OPRK1 gene, and rs910080 (3' UTR _743T>C), rs1997794 (5' UTR -381A>G) and rs1022563 (3' UTR) of the PDYN gene and novelty seeking remain controversial as reported results have not been reproducible. OBJECTIVE: The goal of this study was to determine the frequencies of SNPs rs1042114, rs702764, rs1997794, rs1022563 and rs910080 in the Malaysian population and to study their association with opioid dependence in Malaysian Malays. METHODS: A total of 459 Malay male with opioid dependence and 543 healthy male (controls) subjects were included in this study. SNPs were genotyped using the TaqMan SNP genotyping assay. Statistical analysis was performed using Golden Helix SVS software suite to identify the distribution of allele and genotype frequencies, and SNP-SNP interactions were also analysed in this study. RESULTS AND DISCUSSION: SNP rs1042114 in the OPRD1 gene is strongly associated with opiate addiction (P=.0001). In individuals homozygous for this risk allele, the likelihood of opiate addiction is increased by a factor 1.62 (95% confidence interval (CI) 1.412-1.875). Polymorphic alleles at SNP rs702764 of OPRK1 were not associated with opioid dependence. A significant association between opioid dependence and SNP rs910080 of PDYN (P=.0217) was detected, but there was no association for SNPs rs199774 and rs1022563. A significant interaction was also identified between homozygous wild-type genotype TT of rs702764 with the risk genotypes TG/GG of rs1042114 (odds ratio (OR)=2.111 (95% CI 1.227-3.631), P=.0069) and with the risk genotypes GA/AA of rs910080 (OR=1.415 (95% CI 1.04-1.912), P=.0239). WHAT IS NEW AND CONCLUSION: The results indicate that SNPs rs1042114 and rs910080 contribute to vulnerability to opioid dependence in the Malaysian Malay population. These results will help us to understand the effect of the SNPs and the SNP-SNP interaction on opioid dependence and may assist in efforts to screen vulnerable individuals and match them with individually tailored prevention and treatment strategies.