Viability Of Human Fibroblasts Research Articles

Effect of post-printing curing time on cytotoxicity of direct printed aligners: A pilot study.

The aim of this invitro study was to examine the potential impact of different curing times of 3D-printed orthodontic aligners on their cytotoxicity. Some 60 samples of aligner material were directly 3D printed using Tera Harz TC-85 DAC resin and randomly allocated to three different curing time groups (14, 24 and 50 min). Zendura FLX samples were used as control. The samples were incubated in saliva for 14 days, and then the supernatant was collected. Human gingival fibroblasts (HGF-1)-CRL2014 were used to evaluate potential cytotoxicity. Furthermore, HGF-1 cells were plated on the samples as well as on a glass control sample. After 72 h of growth, their viability was tested. Compared with the glass, only the 50-min curing time markedly reduced fibroblast cell growth. Additionally, a negative linear trend was observed between curing time and fibroblast growth. In comparison with the aligner control group, all samples, including the aligner control samples, exhibited a significant reduction in the viability of human fibroblasts when exposed to saliva. 3D directly printed aligners showed a cytotoxic effect similar to that of thermoformed conventional aligners in terms of fibroblasts growth. A linear trend was found between curing time and cells growth, indicating that directly printed aligners could exhibit higher cytotoxicity if exposed to a longer curing time. This dependence on curing time underscores the importance of following a strict manufacturing process.

Cytotoxicity, Corrosion Resistance, and Wettability of Titanium and Ti-TiB2 Composite Fabricated by Powder Metallurgy for Dental Implants

Objectives: Orthopedics and dentistry have widely utilized titanium alloys as biomaterials for dental implants, but limited research has been conducted on the fabrication of ceramic particle-reinforced Ti composites for further weight reductions. The current study compared titanium–titanium diboride metal composites (Ti-TiB2) with pure titanium (processed by powder metallurgy) in terms of toxicity, corrosion resistance, and wettability. Methods: First, cell lines of a primary dermal fibroblast normal human adult (HDFa) were used to test the cytocompatibility (in vitro) of the composite and pure Ti using an indirect contact approach. Corrosion testing was performed for the materials using electrochemical techniques such as potentiodynamic polarization in a simulated bodily fluid (SBF) in conjunction with a three-electrode electrochemical cell. The entire set of experimental tests was conducted according to the ASTM F746-04 protocol. The contact angles were measured during wettability testing in accordance with ASTM D7334-08. An X-ray diffractometer (XRD) was used to catalog every phase that was visible in the microstructure. A scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) were used to determine the chemical composition. Results: The cytotoxicity tests revealed that there was no detectable level of toxicity, and there was no significant difference in the impact of either of the two materials on the viability of human fibroblasts. An increase in the corrosion resistance of the composite (0.036 ± 0.0001 mpy (millimeters per year)) demonstrated the development of a passive oxide coating. According to the findings, the composites showed a greater degree of hydrophilicity (contact angle 44.29° ± 0.28) than did the pure titanium (56.31° ± 0.47). Conclusions/Significance: The Ti-TiB2 composite showed no toxicity and better corrosion resistance and wettability than did pure Ti. The composite could be a suitable alternative to Ti for applications involving dental implants.

ALK2 and JAK2 Inhibition for Improved Treatment of Anemia in Myelofibrosis Patients: Preclinical Profile of an ALK2 Inhibitor Zilurgisertib in Combination with Ruxolitinib

Introduction: Anemia is a common occurrence in patients with myelofibrosis (MF) and is associated with the need for red blood cell transfusion and poor clinical prognosis. JAK inhibitors such as ruxolitinib are used extensively to treat symptoms of MF and improve quality of life and overall survival. However, JAK inhibitors may also contribute to myelosuppression. Therapeutic interventions that allow for optimization of JAK inhibition with no concern of anemia would benefit patients with MF and potentially lower the rate of treatment discontinuation or suboptimal dosing. Recent studies have demonstrated that inhibition of ACVR1/ALK2, a bone morphogenetic protein receptor that is upstream of the transcriptional regulation of hepcidin, could reduce serum hepcidin levels in patients with MF and improve anemia (Verstovsek S et al. Lancet 2023; Oh S et al. Clin Lymphoma Myeloma Leuk 2022). Reducing levels of hepcidin, a key regulator of plasma iron levels, and restoring erythropoiesis would broadly benefit patients with MF. Based on these recent data, we developed zilurgisertib, a potent and selective ALK2 inhibitor that could be administered in combination with ruxolitinib at doses titrated to the needs of patients with MF. Methods and Results: In biochemical and cellular assays, zilurgisertib inhibited ALK2 kinase activity and SMAD1/5 phosphorylation with IC 50 values of 15 nM and 63 nM, respectively. In Huh-7 cells stimulated with BMP-6, zilurgisertib inhibited hepcidin production with an IC 50 of 20 nM, demonstrating the compound is a potent ALK2 inhibitor capable of regulating iron homeostasis via hepcidin. To assess possible off-target effects of zilurgisertib, kinome profiling at 10 μM ATP was performed at Reaction Biology (Malvern, PA) to determine the overall specificity across 356 kinases (see Figure). At 200 nM, zilurgisertib only inhibited ALK2, ALK1 (to 50%), and ALK6 (to 48%). In addition, zilurgisertib at 20 μM did not affect viability of HEK293 cells, a human cell line commonly used to assess general cell health and compound toxicity. Similarly, zilurgisertib did not affect viability of human fibroblasts or endothelial cells at concentrations up to 5 μM. To test whether the combination of ruxolitinib and zilurgisertib could suppress hepcidin and restore erythropoiesis in an in vivo mouse model of cancer-induced anemia, B16F10 cells were injected intraperitoneally, mimicking a metastatic tumor that leads to anemia 1 week after injection. In a dose-dependent manner, zilurgisertib improved hemoglobin by 2 to 3 g/dL and red blood cell counts, while reducing both liver pSMAD and circulating hepcidin levels by 50% or more compared with vehicle control. The combination of zilurgisertib with ruxolitinib had no effect on this activity, suggesting that inhibition of JAK2 does not inhibit erythropoiesis restored following ALK2 inhibition. Conclusion: Taken together, the potent and selective on-target activity of zilurgisertib suggests that ALK2 inhibition could reduce hepcidin and improve anemia, and that the combination of zilurgisertib with ruxolitinib is a rational and attractive approach to mitigate anemia in patients with MF. The combination of ruxolitinib and zilurgisertib is currently being evaluated in a phase 1 clinical trial in patients with anemia due to myeloproliferative disorders (NCT04455841).

ICVD Polymer Thin Film Bio‐Interface‐Performance for Fibroblasts, Cancer‐Cells, and Viruses Connected to Their Functional Groups and In Silico Studies

AbstractThin polymer coatings are used to improve the interface between biological species and functional materials. Their interaction is significantly influenced by the functional groups and roughness of the polymer film and prediction of the interaction is thus of great interest. However, for conventional polymer films, this cannot be examined independently because of the interplay of defects, residual solvent molecules, roughness, and functional groups. Solvent‐free polymer films prepared by initiated chemical vapor deposition (iCVD) exhibit conformal, defect‐free characteristics and enable precise tailoring of the functional groups. This facilitates to isolate the contribution of functional groups on the bio‐interface performance. Consequently, in silico studies can enable a prediction of ligand interaction in anti‐viral activity for SARS‐CoV‐2 based on defined polymer and key protein structures. Furthermore, the cell viability of human fibroblasts can be traced back to the functional groups of the repeating units. For human liver cancer cell culture, it turns out that more sophisticated models are needed. The insilico‐iCVD approach can enable precise tailoring of complex polymer films optimized for the respective interfaces. In addition, this first big scan of the bio‐interface performance of iCVD films enables a solid starting point in areas like anticancer, antiviral, and biocompatibility for future studies.

The Influence of Bacteriophages on the Metabolic Condition of Human Fibroblasts in Light of the Safety of Phage Therapy in Staphylococcal Skin Infections.

Phage therapy has been successfully used as an experimental therapy in the treatment of multidrug-resistant strains of Staphylococcus aureus (MDRSA)-caused skin infections and is seen as the most promising alternative to antibiotics. However, in recent years a number of reports indicating that phages can interact with eukaryotic cells emerged. Therefore, there is a need to re-evaluate phage therapy in light of safety. It is important to analyze not only the cytotoxicity of phages alone but also the impact their lytic activity against bacteria may have on human cells. As progeny virions rupture the cell wall, lipoteichoic acids are released in high quantities. It has been shown that they act as inflammatory agents and their presence could lead to the worsening of the patient's condition and influence their recovery. In our work, we have tested if the treatment of normal human fibroblasts with staphylococcal phages will influence the metabolic state of the cell and the integrity of cell membranes. We have also analyzed the effectiveness of bacteriophages in reducing the number of MDRSA attached to human fibroblasts and the influence of the lytic activity of phages on cell viability. We observed that, out of three tested anti-Staphylococcal phages-vB_SauM-A, vB_SauM-C and vB_SauM-D-high concentrations (109 PFU/mL) of two, vB_SauM-A and vB_SauM-D, showed a negative impact on the viability of human fibroblasts. However, a dose of 107 PFU/mL had no effect on the metabolic activity or membrane integrity of the cells. We also observed that the addition of phages alleviated the negative effect of the MDRSA infection on fibroblasts' viability, as phages were able to effectively reduce the number of bacteria in the co-culture. We believe that these results will contribute to a better understanding of the influence of phage therapy on human cells and encourage even more studies on this topic.

Toxicity of resin-matrix cements in contact with fibroblast or mesenchymal cells.

The main aim of this study was to perform an integrative review onthe toxic effects of resin-matrix cements and their products in contact with fibroblasts or mesenchymal cells. A bibliographic search was performed on PubMed using the following search terms: "cytotoxicity" AND "fibroblast" OR "epithelial" OR "mesenchymal" AND "polymerization" OR "degree of conversion" OR "methacrylate" OR "monomer" AND "resin cement" OR "resin-based cement". The initial search in the available database yielded a total of 277 articles of which 21 articles were included in this review. A decrease in the viability of mouse fibroblasts ranged between 13 and 15% thatwas recorded for different resin-matrix cements after light curing exposure for 20s. The viability of human fibroblasts was recorded at 83.11% after light curing for 20s that increased up to 90.9% after light curing exposure for 40s. Most of the studies linked the highest toxicity levels when the cells were in contact with Bis-GMA followed by UDMA, TEGDMA and HEMA. Resin-matrix cements cause a cytotoxic reaction when in contact with fibroblasts or mesenchymal cells due to the release of monomers from the polymeric matrix. The amount of monomers released from the resin matrix and their cytotoxicity depends on the polymerization parameters.

Antimicrobial Efficacy of Continuous Low-Irradiance Phototherapy Against Multidrug-Resistant Organisms.

Objective: The objective of this study is to report on the bactericidal effects of blue light administered at low irradiance for extended periods of time. Background: Multidrug-resistant organisms (MDROs) utilize biofilms that can limit the efficacy of antibiotics, causing infection and impaired wound healing. Unlike high-energy systems, continuous low-irradiance phototherapy (CLIP) avoids thermal injury of healthy tissue and can be delivered for extended periods. Methods: Four MDRO species, two of which contained different antibiotic resistance genes, were exposed to 405 nm irradiation in vitro. The microbes were incrementally exposed to increasing dose-rates (irradiance; mW/cm2) over a 24-h time period. Cell viability and biomass reduction assays were conducted to quantify the antibacterial/antibiofilm effects. Primary human dermal fibroblasts were also exposed to CLIP to assess whether these dose-rates would impair cell viability or proliferation. Results: CLIP exposure utilizing irradiances as low as 2.78 mW/cm2 delivered over 24 h resulted in a >3.0-log (>99.9%) and >2.0-log (>99.0%) microbial load reduction when organisms were grown in planktonic and biofilm-encapsulated conditions, respectively. Crystal violet biofilm assays revealed destruction of extracellular biofilm architecture following CLIP exposure. Human fibroblast viability and proliferation were unaffected by CLIP. Conclusions: This is the first report demonstrating the antimicrobial efficacy of CLIP for MDROs found in infected wounds. CLIP did not compromise cultured human fibroblast growth and survival. This study demonstrated that very low fluence rates (irradiances) delivered over extended periods are potently antimicrobial. There is translational potential for CLIP to be fabricated as a wearable device that would enable continuous ambulatory care of wounds.

Evaluation of 3D Printability and Biocompatibility of Microfluidic Resin for Fabrication of Solid Microneedles.

In this study, we have employed Digital Light Processing (DLP) printing technology for the fabrication of solid microneedle (MN) arrays. Several arrays with various geometries, such as cones, three-sided pyramids and four-sided pyramids, with different height to aspect ratios of 1:1, 2:1 and 3:1, were printed. Post-processing curing optimizations showed that optimal mechanical properties of the photocurable resin were obtained at 40 °C and 60 min. Ex vivo skin studies showed that piercing forces, penetration depth and penetration width were affected by the MN geometry and height to aspect ratio. Cone-shaped MNs required lower applied forces to penetrate skin and showed higher penetration depth with increasing height to aspect ratio, followed by three-sided and four-sided printed arrays. Cytotoxicity studies presented 84% cell viability of human fibroblasts after 2.5 h, suggesting the very good biocompatibility of the photocurable resin. Overall, DLP demonstrated excellent printing capacity and high resolution for a variety of MN designs.

Alternative to Poly(2-isopropyl-2-oxazoline) with a Reduced Ability to Crystallize and Physiological LCST.

In this work, we sought to examine whether the presence of alkyl substituents randomly distributed within the main chain of a 2-isopropyl-2-oxazoline-based copolymer will decrease its ability to crystallize when compared to its homopolymer. At the same time, we aimed to ensure an appropriate hydrophilic/lipophilic balance in the copolymer and maintain the phase transition in the vicinity of the human body temperature. For this reason, copolymers of 2-ethyl-4-methyl-2-oxazoline and 2-isopropyl-2-oxazoline were synthesized. The thermoresponsive behavior of the copolymers in water, the influence of salt on the cloud point, the presence of hysteresis of the phase transition and the crystallization ability in a water solution under long-term heating conditions were studied by turbidimetry. The ability of the copolymers to crystallize in the solid state, and their thermal properties, were analyzed by differential scanning calorimetry and X-ray diffractometry. A cytotoxicity assay was used to estimate the viability of human fibroblasts in the presence of the obtained polymers. The results allowed us to demonstrate a nontoxic alternative to poly(2-isopropyl-2-oxazoline) (PiPrOx) with a physiological phase transition temperature (LCST) and a greatly reduced tendency to crystallize. The synthesis of 2-oxazoline polymers with such well-defined properties is important for future biomedical applications.

Chitosan-based nanoparticles as delivery-carrier for promising antimicrobial glycolipid biosurfactant to improve the eradication rate of Helicobacter pylori biofilm

Driven by the need to find alternatives to control H. pylori infections, this work describes the development of chitosan-PMLA nanoparticulate systems as carriers for antimicrobial glycolipid. By using a simple ionic gelation method stable nanoparticle was obtained showing an encapsulation efficiency of 73.1 ± 1.3% and an average size of 217.0 ± 15.6 nm for rhamnolipids chitosan-PMLA nanoparticles (RL-CS-NPs). Glycolipid incorporation and particle size were correspondingly corroborated by FT-IR and TEM analysis. Rhamnolipids chitosan nanoparticles (RL-CS-NPs) presented the highest antimicrobial effect towards H. pylori (ATCC 26695) exhibiting a minimal inhibitory concentration of 132 µg/mL and a biofilm inhibition ability of 99%. Additionally, RL-CS-NPs did not interfere with human fibroblasts viability and proliferation under the tested conditions. The results revealed that the RL-CS-NPs were able to inhibit bacterial growth showing adequate cytocompatibility and might become, after additional studies, a valuable approach to fight H. pylori biofilm related-infections.

Everolimus reduces postoperative arthrofibrosis in rabbits by inducing autophagy-mediated fibroblast apoptosis by PI3K/Akt/mTOR signaling pathway

ObjectiveTo investigate the effects of everolimus (EVE) on postoperative fibrosis in the knee joint and the potentially relevant signaling pathways. MethodsCCK-8 and flow cytometry assays were used to detect the effect of EVE on human fibroblast viability and apoptosis induction. IF and TEM were used to assess fibroblast autophagy. 3-methyladenine (3-MA) was applied to inhibit autophagy to clarify the relationship between autophagy and apoptosis. WB was used to measure the expression of proteins related to apoptosis, autophagy and the mTOR signaling pathway. A rabbit model of knee joint fibrosis was established and topically treated with various concentrations of EVE. IF-P was applied to identify that the main components cells of the fibrotic tissue and histomorphological staining was used to detect the degree of fibrosis and the content of collagen. ResultsHistomorphological staining demonstrated that EVE could reduce the degree of postoperative fibrosis and collagen deposition in the knee joint. The results of IF, TEM, flow cytometry assays and WB detection showed that EVE could activate autophagy and induce fibroblasts apoptosis. Meanwhile, the expression levels of p-PI3K, p-Akt, p-mTOR were downregulated with EVE treatment. After the inhibition of autophagy by 3-MA treatment, the increased fibroblasts apoptosis by EVE treatment was partially decreased. ConclusionEverolimus can reduce surgery-induced knee fibrosis by inducing autophagy-mediated fibroblast apoptosis, which may be involved with the regulation of the PI3K/Akt/mTOR signaling pathway.

Electrospun Fibers and Sorbents as a Possible Basis for Effective Composite Wound Dressings.

Skin burns and ulcers are considered hard-to-heal wounds due to their high infection risk. For this reason, designing new options for wound dressings is a growing need. The objective of this work is to investigate the properties of poly (ε-caprolactone)/poly (vinyl-pyrrolidone) (PCL/PVP) microfibers produced via electrospinning along with sorbents loaded with Argovit™ silver nanoparticles (Ag-Si/Al2O3) as constituent components for composite wound dressings. The physicochemical properties of the fibers and sorbents were characterized using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and inductively coupled plasma optical emission spectroscopy (ICP-OES). The mechanical properties of the fibers were also evaluated. The results of this work showed that the tested fibrous scaffolds have melting temperatures suitable for wound dressings design (58–60 °C). In addition, they demonstrated to be stable even after seven days in physiological solution, showing no macroscopic damage due to PVP release at the microscopic scale. Pelletized sorbents with the higher particle size demonstrated to have the best water uptake capabilities. Both, fibers and sorbents showed antimicrobial activity against Gram-negative bacteria Pseudomona aeruginosa and Escherichia coli, Gram-positive Staphylococcus aureus and the fungus Candida albicans. The best physicochemical properties were obtained with a scaffold produced with a PCL/PVP ratio of 85:15, this polymeric scaffold demonstrated the most antimicrobial activity without affecting the cell viability of human fibroblast. Pelletized Ag/Si-Al2O3-3 sorbent possessed the best water uptake capability and the higher antimicrobial activity, over time between all the sorbents tested. The combination of PCL/PVP 85:15 microfibers with the chosen Ag/Si-Al2O3-3 sorbent will be used in the following work for creation of wound dressings possessing exudate retention, biocompatibility and antimicrobial activity.

Antibacterial Properties of Triethoxysilylpropyl Succinic Anhydride Silane (TESPSA) on Titanium Dental Implants.

Infections related to dental implants are a common complication that can ultimately lead to implant failure, and thereby carries significant health and economic costs. In order to ward off these infections, this paper explores the immobilization of triethoxysilylpropyl succinic anhydride (TESPSA, TSP) silane onto dental implants, and the interaction of two distinct monospecies biofilms and an oral plaque with the coated titanium samples. To this end, titanium disks from prior machining were first activated by a NaOH treatment and further functionalized with TESPSA silane. A porous sodium titanate surface was observed by scanning electron microscopy and X-ray photoelectron spectroscopy analyses confirmed the presence of TESPSA on the titanium samples (8.4% for Ti–N-TSP). Furthermore, a lactate dehydrogenase assay concluded that TESPSA did not have a negative effect on the viability of human fibroblasts. Importantly, the in vitro effect of modified surfaces against Streptococcus sanguinis, Lactobacillus salivarius and oral plaque were studied using a viable bacterial adhesion assay. A significant reduction was achieved in all cases but, as expected, with different effectiveness against simple mono-species biofilm (ratio dead/live of 0.4) and complete oral biofilm (ratio dead/live of 0.6). Nevertheless, this approach holds a great potential to provide dental implants with antimicrobial properties.

Surface functionalization of polypropylene (PP) by chitosan immobilization to enhance human fibroblasts viability

Driven by the market demand, several synthetic and natural grafts have been proposed during the last years for tendons regeneration. The synthetic grafts, which present a better mechanical performance than the natural ones, usually fail due to the lack of biocompatibility and bioactivity. Thus, chitosan (Cs) was immobilized on polypropylene (PP) surface, previously activated by plasma treatment, in order to improve the fibroblasts' adhesion and proliferation on it. The Orange II dye method and FTIR-ATR analysis proved the successful Cs immobilization on the PP surface. It was observed by SEM and optical profilometry analysis that the Cs concentration increase leads to a surface roughness (Ra value) increase, as well as to water contact angle (C.A.) decrease at least until 2% (w/V) of Cs. Using the 2% (V/V) Cs solution concentration, according to SEM analysis and resazurin assay, the developed functionalization was well succeeded in improving fibroblasts adhesion and proliferation on PP substrates surface over 7 days of culture.

Biotechnological approach to induce human fibroblast apoptosis using superparamagnetic iron oxide nanoparticles

Cancer-Associated Fibroblasts (CAFs) contribute to tumour progression and have received significant attention as a therapeutic target. These cells produce growth factors, cytokines and chemokines, stimulating cancer cell proliferation and inhibiting their apoptosis. Recent advances in drug delivery have demonstrated a significant promise of iron oxide nanoparticles in clinics as theranostic agents, mainly due to their magnetic properties. Here, we designed superparamagnetic iron oxide nanoparticles (SPIONs) to induce apoptosis of human fibroblasts. SPIONs were synthesized via co-precipitation method and coated with sodium citrate (SPION_Cit). We assessed the intracellular uptake of SPIONs by human fibroblast cells, as well as their cytotoxicity and ability to induce thermal effects under the magnetic field. The efficiency and time of nanoparticle internalization were assessed by Prussian Blue staining, flow cytometry and transmission electron microscopy. SPIONs_Cit were detected in the cytoplasm of human fibroblasts 15 min after in vitro exposure, entering into cells mainly via endocytosis. Analyses through Cell Titer Blue assay, AnnexinV-fluorescein isothiocyanate (FITC) and propidium iodide (PI) cellular staining demonstrated that concentrations below 8 × 10−2 mg/mL of SPIONs_Cit did not alter cell viability of human fibroblast. Furthermore, it was also demonstrated that SPIONs_Cit associated with alternating current magnetic field were able to induce hyperthermia and human fibroblast cell death in vitro, mainly through apoptosis (83.5%), activating caspase 8 (extrinsic apoptotic via) after a short exposure period. Collectively these findings suggest that our nanoplatform is biocompatible and can be used for therapeutic purposes in human biological systems, such as inducing apoptosis of CAFs.

Comparative evaluation of the effect of curcumin and chlorhexidine on human fibroblast viability and migration: An in vitro study.

Background and Objective:Chemical plaque control acts as an adjunct to mechanical periodontal therapy. Chlorhexidine (CHX) is considered as the gold standard in chemical plaque control, but the main concern is about its fibroblast cytotoxicity. Curcumin, a lipophilic polyphenol, may offer as a promising antiplaque agent. This study was conducted to compare the effect of curcumin (0.003%, 0.03%, 0.06%, 0.1%, and 0.12%) and CHX (0.03%, 0.06%, 0.1%, 0.12%, and 0.2%) on gingival fibroblast cell viability and wound healing at different time periods (1, 2, 4, 6, 8, and 10 min).Materials and Methods:The minimum inhibitory concentration (MIC50) was determined before the evaluation of cytotoxicity and wound healing property. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and morphological examination by direct invert microscopy were carried out to determine cytotoxicity. Wound healing was evaluated by scratch wound assay.Results and Discussion:The MIC50 of CHX and curcumin was at 0.1% and 0.003%, respectively. The mean percentage of fibroblast viability at different concentrations of CHX and curcumin at each time period showed a significant difference. Curcumin exhibited less cytotoxicity as compared to CHX at all concentrations and at varying time periods. There was a significant difference between mean percentage of fibroblast viability at MIC50 of CHX (0.1%) and curcumin (0.003%) at different time periods. The difference between percentage wound healing at antibacterial concentrations of CHX and curcumin at varying time periods was significant.Conclusion:The antibacterial concentration of curcumin (0.003%) exhibits less fibroblast cytotoxicity and excellent wound healing property as compared to CHX. Curcumin may offer as a promising chemical plaque control agent which is less cytotoxic, cost-effective, safe, easily available, and with a possibly beneficial effect on wound healing.

Effect of different preparation techniques of red dragon fruit (Hylocereus polyrhizus) extracts on normal human fibroblast viability

Red dragon fruit is one of the popular fruits that have been widely used both for consumption and food coloring. The red dragon fruit peel and flesh contain various antioxidant compounds that can be used as pharmaceutics and nutraceuticals. The objective of this study was to determine the effect of various extract preparations of the peel and the flesh of red dragon fruit on the viability of normal human fibroblasts. Seven conditions of peel and flesh extracts were prepared as follows, i.e. dried peel ethanolic extract, fresh blended peel ethanolic extract, dried flesh, fresh blended flesh ethanolic extract, blended fresh flesh, filtrate of pressed flesh, and pomace of pressed flesh. Each sample preparation was tested for its effect on the viability of normal human fibroblasts using MTT assay. Results showed that dried peel ethanolic extract reduce cell viability. Red dragon fruit flesh extracts caused no significant effect on the fibroblast viability. In conclusion, the fruit flesh extracts are relatively safer to normal cells than the peel extracts. IC 50 value of the ethanolic extract of dried peel was 55.38±3.85 µg/mL, while the IC 50 value of various types of flesh extract were more than 500 µg/mL.

Cytoprotective Effects of Dinitrosyl Iron Complexes on Viability of Human Fibroblasts and Cardiomyocytes.

Nitric oxide (NO) is an important signaling molecule that plays a key role in maintaining vascular homeostasis. Dinitrosyl iron complexes (DNICs) generating NO are widely used to treat cardiovascular diseases. However, the involvement of DNICs in the metabolic processes of the cell, their protective properties in doxorubicin-induced toxicity remain to be clarified. Here, we found that novel class of mononuclear DNICs with functional sulfur-containing ligands enhanced the cell viability of human lung fibroblasts and rat cardiomyocytes. Moreover, DNICs demonstrated remarkable protection against doxorubicin-induced toxicity in fibroblasts and in rat cardiomyocytes (H9c2 cells). Data revealed that the DNICs compounds modulate the mitochondria function by decreasing the mitochondrial membrane potential (ΔΨm). Results of flow cytometry showed that DNICs were not affected the proliferation, growth of fibroblasts. In addition, this study showed that DNICs did not affect glutathione levels and the formation of reactive oxygen species in cells. Moreover, results indicated that DNICs maintained the ATP equilibrium in cells. Taken together, these findings show that DNICs have protective properties in vitro. It was further suggested that DNICs may be uncouplers of oxidative phosphorylation in mitochondria and protective mechanism is mainly provided by the leakage of excess charge through the mitochondrial membrane. It is assumed that the DNICs have the therapeutic potential for treating cardiovascular diseases and for decreasing of chemotherapy-induced cardiotoxicity in cancer survivors.

Development of a poly(vinyl alcohol)/lysine electrospun membrane-based drug delivery system for improved skin regeneration.

Nanofiber-based wound dressings are currently being explored as delivery systems of different biomolecules for avoiding skin infections as well as improve/accelerate the healing process. In the present work, a nanofibrous membrane composed of poly(vinyl alcohol) (PVA) and lysine (Lys) was produced by using the electrospinning technique. Further, anti-inflammatory (ibuprofen (IBP)) and antibacterial (lavender oil (LO)) agents were incorporated within the electrospun membrane through blend electrospinning and surface physical adsorption methods, respectively. The obtained results demonstrated that the PVA_Lys electrospun membranes incorporating IBP or LO displayed the suitable morphological, mechanical and biological properties for enhancing the wound healing process. Moreover, the controlled and sustained release profile attained for IBP was appropriate for the duration of the wound healing inflammatory phase, whereas the initial burst release of LO is crucial to prevent wound bacterial contamination. Indeed, the PVA_Lys_LO electrospun membranes were able to mediate a strong antibacterial activity against both S. aureus and P. aeruginosa, without compromising human fibroblasts viability. Overall, the gathered data emphasizes the potential of the PVA_Lys electrospun membranes-based drug delivery systems to be used as wound dressings.

Antitumoral effects of Amblyomma sculptum Berlese saliva in neuroblastoma cell lines involve cytoskeletal deconstruction and cell cycle arrest.

The antitumor properties of ticks salivary gland extracts or recombinant proteins have been reported recently, but little is known about the antitumor properties of the secreted components of saliva. The goal of this study was to investigate the in vitro effect of the saliva of the hard tick Amblyomma sculptum on neuroblastoma cell lines. SK-N-SK, SH-SY5Y, Be(2)-M17, IMR-32, and CHLA-20 cells were susceptible to saliva, with 80% reduction in their viability compared to untreated controls, as demonstrated by the methylene blue assay. Further investigation using CHLA-20 revealed apoptosis, with approximately 30% of annexin-V positive cells, and G0/G1-phase accumulation (>60%) after treatment with saliva. Mitochondrial membrane potential (Δψm) was slightly, but significantly (p < 0.05), reduced and the actin cytoskeleton was disarranged, as indicated by fluorescent microscopy. The viability of human fibroblast (HFF-1 cells) used as a non-tumoral control decreased by approximately 40%. However, no alterations in cell cycle progression, morphology, and Δψm were observed in these cells. The present work provides new perspectives for the characterization of the molecules present in saliva and their antitumor properties.