Murine Fibroblast NIH3T3 Cells Research Articles

Effect of Low Copper Doping on the Optical, Cytocompatible, Antibacterial, and SARS-CoV-2 Trapping Properties of Calcium Phosphate Glasses.

Calcium phosphate glasses (CPGs) are acquiring great importance in the biomedical field because of their thermomechanical and bioresorbable properties. In this study, optically transparent copper (1 mol %)-doped calcium phosphate glasses (CPGs_Cu) were prepared through the melt-quenching method, and their biocompatibility and antibacterial and antiviral properties were evaluated and compared with undoped CPGs. Biocompatibility was evaluated on murine fibroblast NIH-3T3 cells as a preliminary study of cytocompatibility. The in vitro tests were performed through indirect and direct cytotoxicity analyses by MTT and Alamar Blue assays and supported by electron microscopy observations. Microbiological analyses were performed against the most common Gram-negative and Gram-positive pathogens that cause nosocomial infections: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and the methicillin-resistant Staphylococcus aureus strain. In addition, the bioglass samples were exposed to SARS-CoV-2 to assess their effects on viral survival. The obtained results assessed the biocompatibility of both bioglass types and their ability to reduce the viral load and trap the virus. In addition, Cu2+-doped bioglass was found to be antibacterial despite its low content (1 mol %) of copper, making this a promising candidate material for biomedical applications, e.g., surgery probes, drug delivery, and photodynamic therapy.

Characterization, antimicrobial and cytotoxic activity of polymer blends based on chitosan and fish collagen

This study aims to produce, characterize, and assess the antimicrobial activity and cytotoxicity of polymer blends based on chitosan (CT) and fish collagen (COL) produced by different precipitation methods. Polymer blends were obtained in alkaline (NaOH), saline (NaCl), and alkaline/saline (NaOH/NaCl) solutions with different CT:COL concentration ratios (20:80, 50:50, and 80:20). The polymer blends were characterized by various physicochemical methods and subsequently evaluated in terms of their in vitro antimicrobial and cytotoxicity activity. In this study, the degree of chitosan deacetylation was 82%. The total hydroxyproline and collagen content in the fish matrix was 47.56 mg. g−1 and 394.75 mg. g−1, respectively. The highest yield was 44% and was obtained for a CT:COL (80:20) blend prepared by precipitation in NaOH. High concentrations of hydroxyproline and collagen in the blends were observed when NaOH precipitation was used. Microbiological analysis revealed that the strains used in this work were sensitive to the biomaterial; this sensitivity was dose-dependent and increased with increasing chitosan concentration in the products. The biocompatibility test showed that the blends did not reduce the viability of fibroblast cells after 48 h of culture. An analysis of the microbiological activity of the all-polymer blends showed a decrease in the values of minimal inhibitory concentration (MIC) and minimal bactericidal concentrations (MBC) for S. aureus and P. aeruginosa. The blends showed biocompatibility with NIH-3T3 murine fibroblast cells and demonstrated their potential for use in biomedical applications such as wound healing, implants, and scaffolds.

Anticariogenic Activity of Oregano against Streptococcus Mutans Biofilm for Investigating its Potential Use as an Oral Care Agent

Being consumed as a spice, Origanum species are also utilized for alternative medical treatment and are therefore of great economic importance. This study examined the effect of Origanum vulgare L. subsp. gracile (OVG) essential oil (EO) against planktonic cell growth and biofilm formation of cariogenic Streptococcus mutansas well as its cytotoxic activity. The antimicrobial potential of EO was screened by broth microdilution method. Crystal violet (CV) biofilm assay method has been used to determine the antimicrobial activitiy and the biofilm formation was also displayed through scanning electron microscopy (SEM). The minimum inhibitory concentration (MIC) value of the EO was determined as 2.5±0.31 mg/mL. The EO acted as an anti-biofilm agent by preventing biofilm formation at sub-MIC concentrations (27.15 to 33.2%). The SEM imaging of biofilms treated with EO showed density and morphological changes when compared to the untreated group. To determine the cytotoxicity, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay wascarried out using the NIH-3T3 murine fibroblast cells andand exhibited IC50 value of 427±1.05 μg/mL.This study has shown that with strong antibacterial and antibofilm capacity, the EO of the OVG can be used as a potentialanticariogenicagent in the oral care products.

Direct reprogramming of fibroblasts into diverse lineage cells by DNA demethylation followed by differentiating cultures.

Direct reprogramming, also known as a trans-differentiation, is a technique to allow mature cells to be converted into other types of cells without inducing a pluripotent stage. It has been suggested as a major strategy to acquire the desired type of cells in cell-based therapies to repair damaged tissues. Studies related to switching the fate of cells through epigenetic modification have been progressing and they can bypass safety issues raised by the virus-based transfection methods. In this study, a protocol was established to directly convert fully differentiated fibroblasts into diverse mesenchymal-lineage cells, such as osteoblasts, adipocytes, chondrocytes, and ectodermal cells, including neurons, by means of DNA demethylation, immediately followed by culturing in various differentiating media. First, 24 h exposure of 5-azacytidine (5-aza-CN), a well-characterized DNA methyl transferase inhibitor, to NIH-3T3 murine fibroblast cells induced the expression of stem-cell markers, that is, increasing cell plasticity. Next, 5-aza-CN treated fibroblasts were cultured in osteogenic, adipogenic, chondrogenic, and neurogenic media with or without bone morphogenetic protein 2 for a designated period. Differentiation of each desired type of cell was verified by quantitative reverse transcriptase-polymerase chain reaction/western blot assays for appropriate marker expression and by various staining methods, such as alkaline phosphatase/alizarin red S/oil red O/alcian blue. These proposed procedures allowed easier acquisition of the desired cells without any transgenic modification, using direct reprogramming technology, and thus may help make it more available in the clinical fields of regenerative medicine.

Fungal enzyme-mediated synthesis of chitosan nanoparticles and its biocompatibility, antioxidant and bactericidal properties

This paper reports the synthesis of chitosan nanoparticles (T-CSNPs) using the fungal enzyme of Trichoderma harzianum and its biocompatibility, antioxidant and bactericidal properties. The T-CSNPs synthesis was confirmed by absorbance at 280 nm using UV–Vis spectrophotometer. T-CSNPs were of spherical shape, as evident by field emission transmission electron microscopic (FETEM) analysis, and the average size of T-CSNPs was 90.8 nm, as calculated using particle size analyzer (PSA). The functional groups showed modifications of chitosan in T-CSNPs as evident by fourier-transform infrared spectroscopic (FTIR) analysis. T-CSNPs were found soluble at the wide range of pH, showing 100% solubility at pH 1–3 and 72% at pH 10. The T-CSNPs exhibited antioxidant property in a dose-dependent manner with pronounced activity at 100 mg·mL−1. The T-CSNPs also showed bactericidal activity against Staphylococcus aureus and Salmonella enterica Typhimurium by causing detrimental effects on bacterial cells. The T-CSNPs (50 μg·mL−1) did not display any cytotoxic effect on murine fibroblast NIH-3T3 cells, as evident by cell viability and acridine orange/ethidium bromide staining assays, which confirmed biocompatibility of the nanoparticles. This work suggested further investigations on the utilization of the mycosynthesized nanochitosan in biomedical applications.

Protective properties of Huperzine A through activation Nrf2/ARE-mediated transcriptional response in X-rays radiation-induced NIH3T3 cells.

Huperzine A (HupA), derived from Huperzia Serrata, has exhibited a variety of biological actions, in particular neuroprotective effect. However, the protective activities of HupA on murine embryonic fibroblast NIH3T3 cells after X-rays radiation have not been fully elucidated. Herein, HupA treatment dramatically promoted cell viability, abated a G0/G1 peak accumulation, and ameliorated increase of cell apoptosis in NIH3T3 cells after X-rays radiation. Simultaneously, HupA notably enhanced activities of anti-oxidant enzymes, inhibited activity of lipid peroxide, and efficiently eliminated production of reactive oxygen species in NIH3T3 cells after X-rays radiation. Dose-dependent increase of antioxidant genes by HupA were associated with up-regulated Nrf2 and down-regulated Keap-1 expression, which was confirmed by increasing nuclear accumulation, and inhibiting of degradation of Nrf2. Notably, augmented luciferase activity of ARE may explained Nrf2/ARE-mediated signaling pathways behind HupA protective properties. Moreover, expression of Nrf2 HupA-mediated was significant attenuated by AKT inhibitor (LY294002), p38 MAPK inhibitor (SB202190) and ERK inhibitor (PD98059). Besides, HupA-mediated cell viability, and ROS production were dramatically bated by LY294002, SB202190, and PD98059. Taken together, HupA effectively ameliorated X-rays radiation-induced damage Nrf2-ARE-mediated transcriptional response via activation AKT, p38, and ERK signaling in NIH3T3 cells.

SPION loaded poly(L-lysine)/hyaluronic acid micelles as MR contrast agent and gene delivery vehicle for cancer theranostics

In this work we evaluated the ability of a SPION (Superparamagnetic iron oxide nanoparticle) loaded micelle system to safely and efficiently transfer foreign DNA into cells with the help of poly(L-lysine) (PLL) as DNA-carrier. Average particle size of PLL coated hyaluronic acid (HA) loaded SPION (PLL-HA-SPION) micelle was approximately 200 nm in size with spherical morphology. PLL-HA-SPION micelle was found to be nontoxic to the NIH3T3 (murine fibroblast cells) and the in vitro uptake was also tested in CT-26 (murine colon cancer cells) by prussian blue staining. Agarose gel retardation study showed the efficient binding of PLL-HA-SPION micelle with plasmid DNA (pLuc). The formed PLL-HA-SPION/pLuc complex could be efficiently transfected into CT-26 cell line. Finally, MR imaging was also used to check uptake property of SPION loaded in PLL-HA-SPION/DNA complex in vitro. The result showed that the PLL-HA-SPION micelle can be applied to MR imagingguided gene therapy in vivo and it is also advantageous for using this system for the magnetic hyperthermia based cancer therapy.

Tectona grandis leaf extract, free and associated with nanoemulsions, as a possible photosensitizer of mouse melanoma B16 cell

Over the past six years we have been studying extracts from tropical, specially Amazon, plants, to search for new sensitizers for photodynamic therapy of cancer and infectious diseases. Tectona grandis is a genus of tropical hardwood trees in the mint family, Lamiaceae. That is native to south and southeast Asia, but since the end of the 20th century is also gaining ground in the Amazon. The present work aims to evaluate the photodynamic potential of hydro-alcoholic extract from Tectona grandis LF leaves (TGE) and the same extract prepared as the oil-water nanoemulsion (TGE-NE) against melanoma B16 F10 cells. The method for preparation of a stable nanoemulsion with ~20nm particles associated to the TGE (TGE-NE) was successfully developed. We have shown that both free and nanostructured presentations possess the ability to sensitize B16 F10 cells to red light of the LED in vitro. Photodynamic effect was observed for both TGE and TGE-NE because toxicity increased under illumination with red light. While TGE was highly toxic towards melanoma cells under illumination with red light of the LED, it also possessed significant dark toxicity towards both B16 F10 and murine fibroblast NIH3T3 cells. The TGE-NE showed reasonable photocytotoxicity and was much less toxic towards normal cells in the dark compared to free TGE.

Effect of noncovalent interaction on the self-assembly of a designed peptide and its potential use as a carrier for controlled bFGF release.

Peptide self-assembly is one of the promising bottom-up approaches for creating synthetic supermolecular architectures. Noncovalent interactions such as hydrophobic packing, electrostatic interaction, and polypeptide chain entropy (ΔSC) are the most relevant factors that affect the folding and self-assembly of peptides and the stability of supermolecular structures. The GVGV tetrapeptide is an abundant repeat in elastin, an extracellular matrix protein. In this study, four GVGV-containing peptides were designed with the aim of understanding the effects of these weak interactions on peptide self-assembly. Transmission electron microscopy, circular dichroism spectroscopy, dynamic light scattering measurements, and rheometry assays were used to study the structural features of the peptides. Because self-assembling peptides with different amino acid sequences may significantly affect protein release, basic fibroblast growth factor (bFGF) was used as a model molecule and encapsulated within the P2 (RLDLGVGVRLDLGVGV) hydrogel to study the release kinetics. The results showed that the balance among hydrophobic effects, electrostatic interactions, and chain entropy determined the molecular state and self-assembly of the peptide. Moreover, encapsulation of bFGF within the P2 hydrogel allowed its sustained release without causing changes in the secondary structure. The release profiles could be tuned by adjusting the P2 hydrogel concentration. Cell Counting Kit-8 and Western blot assays demonstrated that the encapsulated and released bFGFs were biologically active and capable of promoting the proliferation of murine fibroblast NIH-3T3 cells, most likely due to the activation of downstream signaling pathways.

"Graft-to" Protein/Polymer Conjugates Using Polynorbornene Block Copolymers.

A series of water-soluble polynorbornene block copolymers prepared via Ring-Opening Metathesis Polymerization (ROMP) were grafted to proteins to form ROMP-derived bioconjugates. ROMP afforded low-dispersity polymers and allowed for strict control over polymer molecular weight and architecture. The polymers consisted of a large block of PEGylated monoester norbornene and were capped with a short block of norbornene dicarboxylic anhydride. This cap served as a reactive linker that facilitated attachment of the polymer to lysine residues under mildly alkaline conditions. The generality of this approach was shown by synthesizing multivalent polynorbornene-modified viral nanoparticles derived from bacteriophage Qβ, a protein nanoparticle used extensively for nanomedicine. The conjugated nanoparticles showed no cytotoxicity to NIH 3T3 murine fibroblast cells. These findings establish protein bioconjugation with functionalized polynorbornenes as an effective alternative to conventional protein/polymer modification strategies and further expand the toolbox for protein bioconjugates.

Characterization of a novel fusion gene EML4-NTRK3 in a case of recurrent congenital fibrosarcoma.

We describe the clinical course of a recurrent case of congenital fibrosarcoma diagnosed in a 9-mo-old boy with a history of hemimelia. Following complete surgical resection of the primary tumor, the patient subsequently presented with bulky bilateral pulmonary metastases 6 mo following surgery. Molecular characterization of the tumor revealed the absence of the prototypical ETV6-NTRK3 translocation. However, tumor characterization incorporating cytogenetic, array comparative genomic hybridization, and RNA sequencing analyses, revealed a somatic t(2;15)(2p21;15q25) translocation resulting in the novel fusion of EML4 with NTRK3. Cloning and expression of EML4-NTRK3 in murine fibroblast NIH 3T3 cells revealed a potent tumorigenic phenotype as assessed in vitro and in vivo. These results demonstrate that multiple fusion partners targeting NTRK3 can contribute to the development of congenital fibrosarcoma.

Sol–gel synthesis of SiO2–CaO–P2O5 glasses: Influence of the heat treatment on their bioactivity and biocompatibility

The main goal of the present work is to synthesize SiO2·CaO·P2O5 bioactive glasses by a sol–gel method. The influence of the Ca/P molar ratio and of heat treatment on the biological properties of the glassy materials has been investigated. Two gels with different Ca/P molar ratios have been prepared. The gels obtained have been subjected to heat-treatment at three different temperatures: 120°C, 600°C and 1000°C. The bioactivity of the glasses has been evaluated by soaking the samples in a simulated body fluid. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) allowed the presence of an hydroxyapatite layer on the surface of the samples after 7, 14 and 21 days of exposure to be detected. Moreover, the biocompatibility of the obtained glasses has been assessed by means of WST-8 assay using NIH 3T3 murine fibroblast cells. It has been shown that both the Ca/P molar ratio and heat-treatment have a significant influence on the biological properties of the materials. The sample with the higher calcium content and heat-treated at 600°C has been found to be the most bioactive. The biocompatibility of the materials treated at 600°C and 1000°C is much higher than that of those heated at 120°C.

Enterocarpam-III induces human liver and breast cancer cell apoptosis via mitochondrial and caspase-9 activation.

An aristolactam-type alkaloid, isolated from Orophea enterocarpa, is enterocarpam-III (10-amino-2,3,4,6- tetramethoxyphenanthrene-1-carboxylic acid lactam). It is cytotoxic to various human and murine cancer cell lines; however, the molecular mechanisms remain unclear. The aims of this study were to investigate cytotoxic effects on and mechanism (s) of human cancer cell death in human hepatocellular carcinoma HepG2 and human invasive breast cancer MDA-MB-231 cells compared to normal murine fibroblast NIH3T3 cells. Cell viability was determined by MTT assay to determine IC10, IC20 and IC50 levels, reactive oxygen species (ROS) production with 2',7'-dichlorohydrofluorescein diacetate and the caspase-3, -8 and -9 activities using specific chromogenic (p-nitroaniline) tetrapeptide substrates, viz., DEVD-NA, IETD-NA and LEHD-NA and employing a microplate reader. Mitochondrial transmembrane potential (MTP) was measured by staining with 3, 3'-dihexyloxacarbocyanine iodide (DiOC6) and using flow cytometry. The compound was cytotoxic to HepG2 and MDA-MB-231 cells with the IC50 levels of 26.0±4.45 and 51.3±2.05 μM, respectively. For murine normal fibroblast NIH3T3 cells, the IC50 concentration was 81.3±10.1 μM. ROS production was reduced in a dose-response manner in HepG2 cells. The caspase-9 and -3 activities increased in a concentration-dependent manner, whereas caspase-8 activity did not alter, indicating the intrinsic pathway activation. Enterocarpam-III decreased the mitochondrial transmembrane potential (MTP) dose-dependently in HepG2 cells, suggesting that the compound induced HepG2 cell apoptosis via the mitochondrial pathway. In conclusion, enterocarpam-III inhibited HepG2 and MDA-MB-231 cell proliferation and induced human HepG2 cells to undergo apoptosis via the intrinsic (mitochondrial) pathway and induction of caspase-9 activity.

Combinatorial therapy using negative pressure and varying lithium dosage for accelerated wound healing

In this work, we investigated the effects of negative pressure, applied using a pump designed for Negative Pressure Wound Therapy (NPWT), on the process of wound healing in vitro via initiation of the Wnt signaling pathway. Results indicate that negative pressure enhanced Wnt signaling and migration into a simulated wound in vitro in NIH-3T3 murine fibroblast cells. Increasing doses of lithium (upto 15mM) increased basal Wnt signaling and enhanced cell migration into the simulated wound site. A combination of negative pressure and increased doses of lithium synergistically increased Wnt signaling and demonstrated further enhanced cell migration into simulated wound sites, with maximal filling of the simulated wound observed at lithium concentrations of at least 10mM.

Stigmalactam from Orophea enterocarpa induces human cancer cell apoptosis via a mitochondrial pathway.

Stigmalactam, an aristolactam-type alkaloid extracted from Orophea enterocarpa, exerts cytotoxicity against several human and murine cancer cell lines, but the molecular mechanisms remain elusive. The aims of this study were to identify the mode and mechanisms of human cancer cell death induced by stigmalactam employing human hepatocellular carcinoma HepG2 and human invasive breast cancer MDA-MB-231 cells as models, compared to normal murine fibroblasts. It was found that stigmalactam was toxic to HepG2 and MDA-MB-231 cells with IC50 levels of 23.0±2.67 μM and 33.2±4.54 μM, respectively, using MTT assays. At the same time the IC50 level towards murine normal fibroblast NIH3T3 cells was 24.4±6.75 μM. Reactive oxygen species (ROS) production was reduced in stigmalactam-treated cells dose dependently after 4 h of incubation, indicating antioxidant activity, measured by using 2',7',-dichlorohydrofluorescein diacetate and flow cytometry. Caspase-3 and caspase-9 activities were increased in a dose response manner, while stigmalactam decreased the mitochondrial transmembrane potential dose-dependently in HepG2 cells, using 3,3'-dihexyloxacarbocyanine iodide and flow cytometry, indicating mitochondrial pathway-mediated apoptosis. In conclusion, stigmalactam from O. enterocarpa was toxic to both HepG2 and MDA-MB-231 cells and induced human cancer HepG2 cells to undergo apoptosis via the intrinsic (mitochondrial) pathway.

Cytotoxic and Apoptotic-inducing Effects of Purple Rice Extracts and Chemotherapeutic Drugs on Human Cancer Cell Lines

Pigmented rice is mainly black, red, and dark purple, and contains a variety of flavones, tannin, polyphenols, sterols, tocopherols, γ-oryzanols, amino acids, and essential oils. The present study evaluated the cytotoxic effects of purple rice extracts (PREs) combined with chemotherapeutic drugs on human cancer cells and mechanisms of cell death. Methanolic (MeOH) and dichloromethane (DCM) extracts of three cultivars of purple rice in Thailand: Doisaket (DSK), Nan and Payao (PYO), were tested and compared with white rice (KK6). Cytotoxicity was determined by 3-(4, 5-dimethyl)-2, 5-diphenyltetrazolium bromide (MTT) assay in human hepatocellular carcinoma HepG2, prostate cancer LNCaP and murine normal fibroblast NIH3T3 cells. MeOH-PYO-PRE was the most cytotoxic and inhibited HepG2 cell growth more than that of LNCaP cells but was not toxic to NIH3T3 cells. When PREs were combined with paclitaxel or vinblastine, they showed additive cytotoxic effects on HepG2 and LNCaP cells, except for MeOH-PYO-PRE which showed synergistic effects on HepG2 cells when combined with vinblastine. MeOH-PYO-PRE plus vinblastine induced HepG2 cell apoptosis with loss of mitochondrial transmembrane potential (MTP) but no ROS production. MeOH-PYO-PRE-treated HepG2 cells underwent apoptosis via caspase-9 and-3 activation. The level of γ-oryzanol was highest in DCM-PYO-PRE (44.17 mg/g) whereas anthocyanin content was high in MeOH-PYO-PRE (5.80 mg/g). In conclusion, methanolic Payao purple rice extract was mostly toxic to human HepG2 cells and synergistically enhanced the cytotoxicity of vinblastine. Human HepG2 cell apoptosis induced by MeOH-PYO-PRE and vinblastine was mediated through a mitochondrial pathway.

Targeted delivery of microRNA-145 to metastatic breast cancer by peptide conjugated branched PEI gene carrier

Development of a targeted polymeric gene delivery system is essential for reducing the non-specific uptake and toxicity of the gene carriers. In this study, we have tested the specificity of the cell penetrating peptide (DS 4-3), screened by phage display technique, towards metastatic breast cancer cells. This peptide has shown specificity towards metastatic breast cancer cells, which was confirmed through endocytosis inhibition study. Furthermore, the DS 4-3 peptide was conjugated to bPEI, to deliver the therapeutic miR-145. Tumor suppressor miR-145 inhibited tumor cell growth, and significantly suppressed cell invasion. The DS 4-3 peptide conjugated branched PEI (DSbPEI)/pLuc nanoparticles showed increased transfection in malignant murine breast cancer cells at the neutral surface charge (N/P molar ratio of 3), compared to scramble peptide conjugated bPEI/pLuc nanoparticles, without causing any cytotoxicity. This specific increase in transfection with DS-bPEI/pLuc nanoparticles was not found in the cancer cells that originated from different tissue, such as HeLa cervical cancer cells, or in the normal cells, such as NIH-3T3 murine fibroblast cells. Thus, the specific transfection of miR-145 in metastatic breast cancer cells mediated by DS-bPEI resulted in enhanced reduction in proliferation. Open image in new window

Abstract 3807: Regulation of pancreatic, gliosarcoma and non-small cell lung cancer via CPI-613, a novel anticancer therapeutic agent

Abstract While the novel anticancer agent CPI-613, currently in clinical trials, is primarily known to affect multiple cancer cell energy metabolic processes and pathways, here we demonstrate that CPI-613 also shows cancer-cell-cycle-specific effects on BxPC3 (human pancreatic) cancer cells, SF539 (human gliosarcoma) cells, and H460 (human non-small cell lung cancer) cells but not on non-transformed NIH3T3 (murine fibroblast) cells. Specifically, gene microarray data demonstrates that CPI-613 affects signal transduction pathways and genes related to cell cycle maintenance and progression as well as energetic metabolic processes and pathways. The total RNA production was also significantly reduced in cancer cells treated with CPI-613 compared to non treated controls. Multiple cyclins, p27, p19, and CDK2 are specifically noted to be downregulated in cancer cells treated with this drug, thereby halting the cell cycle at multiple points. Further study of this phenomenon may lead to additional indications for CPI-613 treatment. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3807. doi:1538-7445.AM2012-3807

Nacre-driven water-soluble factors promote wound healing of the deep burn porcine skin by recovering angiogenesis and fibroblast function

To assess the recovery effect of water-soluble components of nacre on wound healing of burns, water-soluble nacre (WSN) was obtained from powdered nacre. Alterations to WSN-mediated wound healing characteristics were examined in porcine skin with deep second-degree burns; porcine skin was used as a proxy for human. When WSN was applied to a burned area, the burn-induced granulation sites were rapidly filled with collagen, and the damaged dermis and epidermis were restored to the appearance of normal skin. WSN enhanced wound healing recovery properties for burn-induced apoptotic and necrotic cellular damage and spurred angiogenesis. Additionally, WSN-treated murine fibroblast NIH3T3 cells showed increased proliferation and collagen synthesis. Collectively, the findings indicate that WSN improves the process of wound healing in burns by expeditiously restoring angiogenesis and fibroblast activity. WSN may be useful as a therapeutic agent, with superior biocompatibility to powdered nacre, and evoking less discomfort when applied to a wounded area.

Cytotoxicity of 1-alkylquinolinium bromide ionic liquids in murine fibroblast NIH 3T3 cells

Minimal toxicity data are available for 1-alkylquinolinium bromide ionic liquids. Here, their toxicity to NIH 3T3 murine fibroblast cells, of relevance to their potential antimicrobial application, is presented. Toxicity data, presented by time-point analysis with a particular focus on the immediate toxicity upon short term cellular exposure, indicate a link between the length of the alkyl chain cationic substituent and resultant biological toxicity. 1-Tetradecylquinolinium bromide was found to exhibit cellular toxicity comparable to benzalkonium chloride over all time points tested. By comparison, 1-octylquinolinium bromide initially exerted significantly lower cytotoxicity at one hour; however, toxicity was found to have a cumulative effect over time-course analysis up to three days. This illustrates that cationic substituent alkyl chain length may govern not only overall toxicity, but also the rate of toxicity. Fluorescence microscopy was utilised to examine destabilisation of the plasma membrane by 1-tetradecylquinolinium bromide and benzalkonium chloride after one hour, with membrane destabilisation not observed for 1-octylquinolinium bromide, or the base constituent quinoline.