Chitosan–Pluronic nanoparticles as oral delivery of anticancer gemcitabine: preparation and in vitro study

Nanoparticles have proven to be an effective delivery system with few side effects for anticancer drugs. In this study, gemcitabine-loaded nanoparticles have been prepared by an ionic gelation method using chitosan and Pluronic® F-127 as a carrier. Prepared nanoparticles were characterized using dynamic light scattering, Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopy, and transmission electron microscopy. Different parameters such as concentration of sodium tripolyphosphate, chitosan, Pluronic, and drug on the properties of the prepared nanoparticles were evaluated. In vitro drug release was studied in phosphate-buffered saline (PBS; pH = 7.4). The cytotoxicity of the nanoparticles was assayed in the HT-29 colon cancer cell line. The mucoadhesion behavior of the nanoparticles was also studied by mucus glycoprotein assay. The prepared nanoparticles had a spherical shape with positive charge and a mean diameter ranging between 80 to 170 nm. FT-IR and DSC studies found that the drug was dispersed in its amorphous form due to its potent interaction with nanoparticle matrix. Maximum drug encapsulation efficiency was achieved at 0.4 mg/mL gemcitabine while maximum drug loading was 6% obtained from 0.6 mg/mL gemcitabine. An in vitro drug release study at 37°C in PBS (pH = 7.4) exhibited a controlled release profile for chitosan–Pluronic® F-127 nanoparticles. A cytotoxicity assay of gemcitabine-loaded nanoparticles showed an increase in the cytotoxicity of gemcitabine embedded in the nanoparticles in comparison with drug alone. The mucoadhesion study results suggest that nanoparticles could be considered as an efficient oral formulation for colon cancer treatment

Lentiviral Mediated Overexpression of NGF in Adipose-derived Stem Cells

Introduction: Human adipose-derived stem cells (ADSCs) are multipotent stem cells that can self-renew and differentiate into various types of cells such as adipocytes, osteocytes, and neural cells. These stem cells can be isolated by minimally invasive technique in large amounts. ADSCs are a useful resource for cell therapy and regenerative medicine. Nerve growth factor (NGF) is the first neurotrophin factor discovered and characterized for its anti-apoptotic role in neural development. NGF can promote neuronal survival and neurite outgrowth and it also promotes neuron differentiation and migration. Moreover, research showed that NGF could protect axons from inflammatory damage, improve cognitive function in damaged brain models, and function in the prevention and treatment of neurological diseases like Alzheimer’s disease. In this study we use Lentiviral vector-mediated gene transfer technique to deliver NGF gene to ADSCs and overexpress this factor in ADSCs. Method and Materials: ADSCs extracted from human adipose tissue after lipoaspiration by digestion method. ADSCs characterized with Flowcytometry and differentiation assay in adipogenic and osteogenic differential media. The NGF gene was cloned in pCDH-513B-1 (System Bioscience, Mountain View, CA, United States) under a cytomegalovirus (CMV) promoter. Recombinant lentiviruses were produced according to the Prof. Trono lab protocol with some modifications in HEK 293T cells. The spinfection method was used to transduce ADSCs. NGF expression was assayed using fluorescent microscope to trace green fluorescent protein (GFP) marker, RT-PCR and western blotting. Results: Extracted ADSCs had mesenchymal morphology and differentiated into adipocytes and osteocytes in differentiating media. HEK293T easily transfected with pCDH-513B-1 and over 99% of them expressed GFP so we gathered pseudoviruses from the supernatant. ADSCs transduced with these pseudoviruses transferred NGF and after transduction expressed GFP, as seen under fluorescent microscope. RT-PCR and western blotting verified NGF overexpression in them

Mesoporous silica nanoparticles functionalized with folic acid/methionine for active targeted delivery of docetaxel

Abstract: Mesoporous silica nanoparticles (MSNs) are known as carriers with high loading capacity and large functionalizable surface area for target-directed delivery. In this study, a series of docetaxel-loaded folic acid- or methionine-functionalized mesoporous silica nanoparticles (DTX/MSN-FA or DTX/MSN-Met) with large pores and amine groups at inner pore surface properties were prepared. The results showed that the MSNs were successfully synthesized, having good pay load and pH-sensitive drug release kinetics. The cellular investigation on MCF-7 cells showed better performance of cytotoxicity and cell apoptosis and an increase in cellular uptake of targeted nanoparticles. In vivo fluorescent imaging on healthy BALB/c mice proved that bare MSN-NH2 are mostly accumulated in the liver but MSN-FA or MSN-Met are more concentrated in the kidney. Importantly, ex vivo fluorescent images of tumor-induced BALB/c mice organs revealed the ability of MSN-FA to reach the tumor tissues. In conclusion, DTX/MSNs exhibited a good anticancer activity and enhanced the possibility of targeted drug delivery for breast cancer

Assesment Of The Efficacy Of HESA-A On The Proliferation And Apoptosis Of Chronic Myelogenous Leukemia Cell Line(K562)

Background and Aim: Chronic myelogenous leukemia is characterized by Philadelphia (Ph) chromosome, the presence of BCR-ABL fusion gene and constitutive activation of the ABL1 tyrosine kinase. Despite an excellent result of target therapy by imatinib, some patients develop resistance to imatinib. In this study Efficacy of HESA-A on proliferation and apoptosis of K562 cell line was assessed. Materials and Methods: In this study doubling time of K562 cell line was calculated. The cells were affected by various concentrations of HESA-A(1,2,4 and 8 mg/ml respectively). Cytotoxicity and IC50 dose of HESA-A were detected by MTT and trypan blue exclusion assay. Apoptosis was assessed by flowcytometry after 48 h cell treatment in the presence of IC50 dose. Results: Doubling time of K562 cells was 24 hours. HESA-A reduced the number of viable K562 cells in a concentration dependent manner.IC50 dose was 3.5 mg/ml. In flowcytometry analysis of apoptosis, 19.22% of the treated cells were located in the position of the necrotic cells. Conclusion: The results of MTT and trypan blue exclusion assay suggest that HESA-A inhibits the growth of k562 cells in a concentration dependent manner and induces necrosis in K562 cells

Effects of Flavonoid Fractions from Calendula officinalis Flowers in Parent and Tamoxifen Resistant T47D Human Breast Cancer Cells: Effects of flavonoids in human breast cancer cells

Three major flavonoid fractions were separated from a methanol extract of Calendula officinalis flowers by preparative TLC. These fractions were evaluated for the inhibition of parent and tamoxifen resistant T47D human breast cancer cells. We also examined the effect of quercetin and isorhamnetin on the growth of parent and resistant T47D cells in the presence and absence of tamoxifen. It was foundthat quercetin increased cell proliferation of the resistant T47D cells at the presence of tamoxifen but no effect was detected by using quercitin alone. The fractions isolated from Calendula officinalis did not show any inhibitory effects on the cells.Isorhamnetin did not have any proliferative or anti-proliferative activity on the both cell lines

Effects of different periods of renal ischemia on liver as a remote organ

AIM: To assess the hepatic changes after induction of different periods of renal ischemia

Potential of Treated Dentin Matrix Xenograft for Dentin-Pulp Tissue Engineering

Introduction: This study aims to develop and characterize the regenerative potential of an atelopeptidized treated dentin matrix xenograft using in vitro and in vivo models. Methods: Freshly extracted bovine dentin was pulverized into 250- to 500-mu m particles and demineralized with 17% EDTA for 1, 7, and 13 days. The samples were atelopeptidized with pepsin. The degree of demineralization and the effect of atelopeptidization were assessed using field emission scanning electron microscopy combined with energy-dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy, respectively. The expression of dentin matrix acidic phosphoprotein 1, dentin sialophosphoprotein, and osteopontin was evaluated in dental pulp stem cells using quantitative real-time polymerase chain reaction. The samples were then implanted intramuscularly in rats for 30 days, and the inflammatory cells were quantified histologically. Results: Field emission scanning electron microscopy combined with energy-dispersive X-ray spectroscopy revealed an exposed tubular structure of dentin after 1 and 7 days of demineralization. Fourier transform infrared spectroscopy confirmed the absence of amide peaks at 1260 to 1640/cm after atelopeptidization. The dental pulp stem cell expression of dentin matrix acidic phosphoprotein 1 and dentin sialophosphoprotein increased in all compared with the untreated control group (P < .05). The maximum expression rates were observed for the 1-day demineralized and atelopeptidized group. The 1-day demineralized group elicited the highest inflammatory response compared with the 7- or 13-day demineralized groups (P < .001). Atelopeptidization significantly decreased the inflammatory response only in the 1-day demineralized dentin group (P < .05). Conclusions: Atelopeptidization of 1-day demineralized dentin xenograft preserved the collagen structure, minimized the immune reaction, and provided sufficient regenerative potential

Pulp ECM-derived macroporous scaffolds for stimulation of dental-pulp regeneration process

Objective. Recent studies suggest xenogeneic extracellular matrices as potential regenerative tools in dental pulp regeneration. This study aimed to fabricate and characterize a novel three-dimensional macroporous pulp-derived scaffold that enables the attachment, penetration, proliferation and differentiation of mesenchymal stem cells. Method. Bovine pulp was decellularized and characterized with histological and DNA content methods. This scaffold was prepared using finely milled lyophilized decellularized pulp extracellular matrix (ECM) digested with pepsin. Three different concentrations of ECM (1.50, 2.25 and 3.00 mg/ml) were freeze-dried and were tested with/without chemical crosslinking. The specimens were subjected to physicochemical characterization, cell viability and quantitative real time polymerase chain reaction assessments with human bone marrow mesenchymal stem cells (hBMMSCs). All scaffolds were subcutaneously implanted in rats for two weeks and histological and immunostaining analyses were performed. Results. Histological and DNA analysis confirmed complete decellularization. All samples demonstrated more than 97% porosity and 1.50 mg/ml scaffold demonstrated highest water absorption. The highest cell viability and proliferation of hBMMSCs was observed on the 3.00 mg/ml crosslinked scaffolds. The gene expression analysis showed a significant increase of dmp-1 and collagen-I on 3.00 mg/ml crosslinked scaffolds compared to the other scaffolds. Histological examination of subcutaneous implanted scaffolds revealed low immunological response, and enhanced angiogenesis in cross-linked samples compared to non-crosslinked samples. Significance. The three-dimensional macroporous pulp-derived injectable scaffold developed and characterized in this study displayed potential for regenerative therapy. While the scaffold biodegradability was decreased by crosslinking, the biocompatibility of post-crosslinked scaffold was significantly improved. (C) 2019 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved