Cell Cytotoxicity Assay Research Articles

Evaluation of Cytotoxicity and Taste-Masking Effect of Selected Flavors on Dental Lidocaine HCl Injection.

Aim: Anxiety and intolerance to dental local anesthetic injections are common in patients undergoing dental procedures. This work was designed to study cytotoxicity of selected flavors in primary gingival keratinocytes (PGK), to acquire information on their suitability for use in dental lidocaine hydrochloride (LID) injection. We also evaluated the bio-mimetic taste of LID dental injection in the presence of selected flavors and sweetener using an Astree electronic tongue (ETongue). Methods: The cytotoxicity of chocolate natural and artificial flavor (CTE), raspberry flavor artificial (RAS), cherry flavor (CHR), bitterness suppressor flavor (BSF) and lemon flavor extract (LFE) at various dilutions (0.16–10% v/v) was carried out in PGK using the live cell morphological analysis and MTT cell cytotoxicity assay. Based on the cytotoxicity data, CTE and RAS were added to Xylocaine® (2%) along with 0.09% sodium saccharin and taste was assessed using an ETongue. Results: After three hours of treatment, a dose-dependent cell death was induced by all flavors compared to the untreated control. BSF was found to be more toxic when compared to other flavors. CTE was found to be less toxic. The mean IC50 values of CTE, RAS, CHR, BSF and LFE in PGK were found to be 9.54, 8.43, 2.21, 0.38 and 4.01 mg/mL. Taste analysis with the ETongue showed a clear taste difference between the control and test formulations containing CTE and RAS flavors along with sodium saccharin. Conclusion: CTE and RAS flavors in combination with 0.09% sodium saccharin can achieve a significant taste-masking effect in the dental LID injection.

In vitro Cytotoxicity Analysis of Hybrid Graphene Oxide (hGO) Nano Structures in Caprine Wharton’s Jelly Derived Mesenchymal Stem Cells (WJ-MSCs)

Background: Nanotechnology is used in stem cell culture as well as in vivo delivery and tracking of stem cells. Graphene oxide (GO) is a carbon based nanomaterial and it has large surface area as well as good biocompatibility and heteroatoms doped GO exploit its properties. Hybrid GO (hGO) nano structures biocompatibility is depends on its size, dose and exposure time as well as in vitro cell models and hence, need thorough cytotoxicity studies in different species in vitro cell models. Methods: Caprine Wharton’s jelly derived mesenchymal stem cells (WJ-MSCs) were isolated, characterized and dose dependent (100, 50, 25, 10 and 0µg /ml) in vitro cytotoxicity of three different hGO nano structures (phosphorus doped graphene oxide titanium oxide tubes, rods and sheets) were analysed in caprine WJ-MSCs by studying cell cytotoxicity assays. Result: All three hGO nano structures were damaged cell morphology at 100 and 50 µg /ml doses, however, morphologically more good cells were observed in hGO tubes treated group than hGO rods and hGO sheets at 25 and 10 µg/ml doses as compared to control. Cell viability percentage was significantly (P less than 0.01) decreased at dose 100 µg/ml and it was significantly (P less than 0.01) increased at 25 µg/ml dose as compared to 50, 10 and 0 µg/ml doses. But, hGO tubes significantly (P less than 0.01) increased cell viability % as compared to hGO rods and hGO sheets. Cell population doubling time (PDT) was not altered significantly by all hGO nano structures, but 100 and 50 µg/ml doses significantly (P less than 0.01)increased cell PDT as compared to 25, 10 and 0 µg/ml doses. All hGO nano structures were non significantly altered growth curve, however, all hGO nano structures at 25 µg /ml dose altered (inclined) shape of growth curve, while 100 and 50 µg /ml doses significantly declined growth curve shape as compared to 10 and 0 µg /ml doses. Cell proliferation % was significantly (P less than 0.01) increased at 25 and 10 µg/ml doses, while, it was significantly (P less than 0.01) decreased at 100 µg /ml dose as compared to 50 and 0 µg /ml. However, there was no significance difference was observed in cell proliferation % in groups treated by different hGO nanostructures. In last, it was concluded as, hGO nano structures cytotoxicity was dose dependent and hGO nano tubes were least cytotoxic in caprine WJ-MSCs.

Potent antitumor activity of cepharanthine against triple-negative breast cancer spheroids compared with tetrandrine.

Cepharanthine (CEP) is a bis-bynzelisoquinoline alkaloid from the same class as the anticancer agent tetrandrine (TET). However, the effects of CEP against breast cancer have not been extensively studied, despite its long therapeutic history with low toxicity against other types of cancer. 3D culture systems more accurately mimic the human body and address the limitations of determining drug effectiveness compared with 2D culture systems. In the present study, the antitumor activities of TET and CEP were compared in 3D culture systems in triple-negative breast cancer (TNBC) MDA-MB-231 and estrogen receptor-positive breast cancer MCF-7 cell lines. Cell viability, apoptosis and cytotoxicity assays were performed to determine the total number of live or dead cells, the IC50 values, the number of apoptotic cells and spheroid roundness. Viability suppression of MDA-MB-231 cells was significantly greater with both TET and CEP compared with that of MCF-7 cells, and the roundness of MDA-MB-231 spheroids treated with CEP was decreased significantly compared with that of spheroid treated with TET. Cytoplasmic shrinkage in each cell line significantly increased with the treatment of TET compared with the control; however, this effect was stronger with CEP. The ratio of dead/live cells in each cell line treated with TET and CEP increased in a dose-dependent manner. Overall, the present study demonstrated that CEP had greater cell toxicity in 3D spheroids of breast cancer cells compared with TET, suggesting that CEP may have a stronger antitumor activity on TNBC spheroids compared with TET.

Withametelin: a biologically active withanolide in cancer, inflammation, pain and depression

Withanolides are natural medicinal agents whose safety and therapeutic profiles make them valuable to mankind. Among multiple withanolides, withametelin is underexplored. The present study was aimed to create a general biological profile of isolated withametelin from Datura innoxia Mill. targeting different biological models. In-silico studies include drug-likeliness, pharmacokinetics, toxicity, molecular targets and cytotoxicity to cancer cell lines predictions. In silico directed preliminary in-vitro evaluation comprised of cancer/normal cell cytotoxicity, DPPH and protein kinase inhibition assays while in-vivo bioactivities include antiinflammatory, analgesic, antidepressant and anticoagulant assays. Pharmacological findings were strengthened by molecular docking studies to check interactions with various proteins and to propose the future path of studies. Results indicated compliance with Lipinski drug-likeliness rule (score −0.55). ADMET prediction showed strong plasma protein binding, GI absorption (Caco-2 cells permeability = 46.74 nm/s), blood brain barrier penetration (Cbrain/Cblood = 0.31), efflux by P-glycoprotein, metabolism by CYP1A2, CYP2C19 and CYP3A4, medium hERG inhibition and non-carcinogenicity in rodents. Predicted molecular targets included mainly receptors (glucocorticoid, kappa opioid, delta opioid, adrenergic and dopamine), oxidoreductase (arachidonate 5-lipoxygenase and cyclooxygenase-2), enzymes (HMG-CoA reductase) and kinase (NFκb). Withametelin was more cytotoxic to cancer cells (DU145 IC50 7.67 ± 0.54 µM) than normal lymphocytes (IC50 33.55 ± 1.31 µM). It also showed good antioxidant and protein kinase inhibition potentials. Furthermore, withametelin (20 mg/kg) significantly reduced inflammatory paw edema (68.94 ± 5.55%), heat-induced pain (78.94 ± 6.87%) and immobility time (50%) in animals. Molecular docking showed hydrogen bonding interactions (binding energies: −11.3 to −7.8 kcal/mol) with arachidonate 5 lipoxygenase, NFκb and glucocorticoid receptor. Withametelin has potential for advance investigations for its cytotoxic, anti-inflammatory, analgesic and antidepressant activities.

Therapeutic Potential Assessment of Green Synthesized Zinc Oxide Nanoparticles Derived from Fennel Seeds Extract.

PurposeTo study the cytotoxic evaluation, antimicrobial and confocal analysis of zinc oxide nanoparticles (ZnO NPs) obtained from a novel plant product fennel (Foeniculum vulgare Mill.) seed extract (FSE).MethodsZnO NPs were analyzed using UV–Vis spectroscopy, XRD, FTIR, TEM and EDX techniques. The MTT cell cytotoxicity assay measured the proliferation and survival of MCF-7 cells treated at different concentrations of FSE-derived ZnO NPs. The antimicrobial activity towards pathogenic bacteria and yeast strains was investigated.ResultsThe UV–Vis spectra showed two peaks at 438 nm and 446 nm, confirming nanoparticle formation. The SEM morphology results showed porous ranging from 23–51 nm. The antitumor activity value (IC50) was at 50 µg/mL and 100 µg/mL. Besides, morphological changes of MCF-7, cells treated at different concentrations of FSE of ZnO NPs were observed in cell cultures transfected with a transient pCMV6-XL4-GFP-expressing vector containing C-terminal domain GFP-tagged proteins, which resulted in an apoptotic effect. Antimicrobial IZ ranged up No Inhibition to 18.00 ± 0.4. The IZ revealed at the highest concentration was E. faecium VRE and yeast Cryptococcus sp. (18.00 ± 0.4. mm), followed by S. aureus (17.00 ± 0.2 mm) and P. aeruginosa and the yeast C. parapsilosis (16 ± 0.4 mm). The IZ was equal to that caused by the nystatin to Cryptococcus sp., which was significantly highest than ampicillin treatments of S. aureus, P. aeruginosa, C. albicans, and C. parapsilosis. The MIC value of the FSE-derived ZnO NPs tested against E.faecium and C.albicans was 6.00 µg/mL (E. faecium and C. albicans). It was 32.00 µg/mL (S. aureus, S. typhimurium and Cryptococcus sp.), 64.00 µg/mL (P. aeruginosa), and 128 µg/mL (C. parapsilosis).ConclusionAs far as it is to our knowledge, this study established, for the first time, the biological activities of biosynthesized ZnO NPs from FSE and their synergistic therapeutic potential.

Celecoxib upregulates ULBP-1 expression in lung cancer cells via the JNK/PI3K signaling pathway and increases susceptibility to natural killer cell cytotoxicity.

Lung cancer has the highest cancer mortality rate in the world, and effective therapies are still required. Cyclooxygenase-2 (COX-2) is highly expressed in numerous types of cancer, and is therefore considered a possible target of cancer treatment. Celecoxib, a selective COX-2 inhibitor, has binding pockets that interact with COX-2 and disrupt its enzymatic activities. In addition, celecoxib is able to affect cellular functions in a COX-2-independent manner. The present study aimed to investigate if celecoxib affected natural killer (NK) cell receptors and susceptibility to NK cell toxicity. For this purpose, PCR, immunoblotting, flow cytometry analysis and NK cell cytotoxicity assays were performed. The present study revealed that sublethal concentrations of celecoxib increased the expression levels of UL16-binding protein 1 (ULBP-1), a natural-killer group 2 member D (NKG2D) ligand, in lung cancer A549 and H460 cell lines. ULBP-1 mRNA and protein expression was induced in a dose- and time-dependent manner after celecoxib treatment. Expression levels of other NKG2D ligands, such as ULBP-2, ULBP-3, MHC class I-related chain A (MICA) and MICB did not change considerably compared to ULBP-1 in response to celecoxib treatment. Fluorescence microscopic images revealed abundant ULBP-1 in the cytoplasm after celecoxib treatment. Both JNK and PI3K may be involved in the induction of ULBP-1 expression after celecoxib treatment in A549 and H460 cells. In a NK cytotoxicity assay, celecoxib increased the sensitivity to NK cell-mediated cytotoxicity via interaction with ULBP-1 in lung cancer cells. Overall, the present results demonstrated that celecoxib treatment induced ULBP-1 expression in lung cancer cells, thereby increasing their susceptibility to NK cell cytotoxicity. These results suggest that the effects of conventional anticancer therapy may potentially be enhanced by using celecoxib, which targets COX-2, to enhance the sensitivity of lung cancer cells to NK cell-mediated cytotoxicity.

IL-27 along with IL-28B ameliorates the pulmonary redox impairment, inflammation and immunosuppression in benzo(a)pyrene induced lung cancer bearing mice

AimsThe major cause behind lung cancer development is exposure to various polycyclic aromatic hydrocarbons like benzo(a)pyrene (BaP) present in tobacco smoke, motor vehicle, and industrial exhaust. BaP is reported to induce the expression of various pro-inflammatory cytokines and matrix remodeling proteins. It is also responsible for dysfunction and exhaustion of the killing capacity of CD8+ T lymphocytes, one of the important components of the immune system which can kill tumor cells. We tried to evaluate the synergistic role of IL-27 and IL-28B in modulation of BaP-induced lung carcinogenesis associated with various hallmarks like pulmonary redox imbalance, angiogenesis, inflammation and cell proliferation in lung tissue. Main methodBaP was treated to Swiss albino mice to develop lung tumor. After the confirmation of lung tumor development Swiss albino mice were treated with IL-27 and IL-28B alone or in combination intraperitoneally. Histological analysis, immunohistochemistry, biochemical assay, western blot analysis, cell cytotoxicity assay, real-time PCR assay etc. were performed to evaluate the modulatory role of IL-27 and IL-28B. Key findingsWe observed that IL-27 and IL-28B were able to suppress the expression of lung cancer-associated NFkB, COX-2, and iNOS. The expression of TNF-α, PCNA and some matrix remodeling enzymes were also modulated upon IL-27 and IL-28B treatment. Although the population of lung residing CD8+ T cells in tumor bearing lung tissue were unresponsive but the activity of systemic CD8+ cells was increased. SignificanceResults hinted that IL-27 along with IL-28B were able to ameliorate various hallmarks ranging from angiogenesis to inflammation associated with the BaP-induced lung carcinogenesis. From this study, we propose that IL-27 and IL28B can be used as immunotherapeutic agent to regulate lung cancer.

Development and biological assessment of MMAE-trastuzumab antibody-drug conjugates (ADCs).

Trastuzumab, a humanized monoclonal antibody targeting Human Epidermal growth factor Receptor 2 (HER2), is a therapeutic option used for the treatment of patients with HER2-overexpressing breast cancers. The primary purpose of the present study wasto establish a trastuzumab-based antibody drug conjugate (ADC) to enhance the biopharmaceutical profile of trastuzumab. In this study, trastuzumab was linked to the microtubule-disrupting agent monomethyl auristatin E (MMAE) through a peptide linker. Following conjugation, MMAE-trastuzumab ADCs were characterized using SDS-PAGE, UV/VIS, and cell-based ELISA. The inhibitory effects of the ADCs were measured on MDA-MB-453 (HER2-positive cells) and HEK-293 (HER2-negative cells) using in vitro cell cytotoxicity and colony formation assays. Our findings showed that approximately 3.4 MMAE payloads were conjugated to trastuzumab. MMAE-trastuzumab ADCs produced six bands, including H2L2, H2L, HL, H2, H, and L in non-reducing SDS-PAGE. The conjugates exhibited the same binding ability to MDA-MB-453 as unconjugated trastuzumab. The MTT assay showed a significant improvement in the trastuzumab activity following MMAE conjugation, representing ahigher antitumor activity as compared with unconjugated trastuzumab. Furthermore, ADCs were capable of potentially inhibiting colony formation in HER2-positive cells, as compared with trastuzumab. MMAE-trastuzumab ADCs represent a promising therapeutic strategy to treat HER2-positive breast cancer.

The SUMO Conjugase Ubc9 Protects Dopaminergic Cells from Cytotoxicity and Enhances the Stability of α-Synuclein in Parkinson's Disease Models.

Small ubiquitin-like modifier (SUMO) is a widespread regulatory mechanism of post-translational modification (PTM) that induces rapid and reversible changes in protein function and stability. Using SUMO conjugase Ubc9-overexpressing or knock-down cells in Parkinson’s disease (PD) models, we demonstrate that SUMOylation protects dopaminergic cells against MPP+ or preformed fibrils (PFFs) of α-synuclein (α-syn)-induced toxicities in cell viability and cytotoxicity assays. In the mechanism of protection, Ubc9 overexpression significantly suppressed the MPP+ or PFF-induced reactive oxygen species (ROS) generation, while Ubc9-RNAi enhanced the toxicity-induced ROS production. Further, PFF-mediated protein aggregation was exacerbated by Ubc9-RNAi in thioflavin T staining, compared with NC1 controls. In cycloheximide (Chx)-based protein stability assays, higher protein level of α-syn was identified in Ubc9-enhanced green fluorescent protein (EGFP) than in EGFP cells. Since there was no difference in endogenous mRNA levels of α-syn between Ubc9 and EGFP cells in quantitative real-time PCR (qRT-PCR), we assessed the mechanisms of SUMO-mediated delayed α-syn degradation via MG132, proteasomal inhibitor, and PMA, lysosomal degradation inducer. Ubc9-mediated SUMOylated α-syn avoided PMA-induced lysosomal degradation because of its high solubility. Our results suggest that Ubc9 enhances the levels of SUMO1 and ubiquitin on α-syn and interrupts SUMO1 removal from α-syn. In immunohistochemistry, dopaminergic axon tips in the striatum and cell bodies in the substantia nigra from Ubc9-overexpressing transgenic mice were protected from MPTP toxicities compared with wild-type (WT) siblings. Our results support that SUMOylation can be a regulatory target to protect dopaminergic neurons from oxidative stress and protein aggregation, with the implication that high levels of SUMOylation in dopaminergic neurons can prevent the pathologic progression of PD.

Abstract 662: A discovery of a small molecule mTORC1 allosteric inhibitor targeting cancer cells

Abstract The allosteric inhibition of the mechanistic target of rapamycin complex 1 (mTORC1), the central growth regulator that is highly activated in cancer cells, is unique for rapamycin and rapalogs. Upon binding to 12-kDa FK506-binding protein (FKBP12), the FKBP12-rapamycin specifically complexed with mTORC1 and inhibits the mediated downstream signals incorporated in metabolic processes. Since rapamycin has a large molecular weight and a poor solubility, it does not completely inhibit mTORC1 due to the pharmacokinetic limitations. It just shows a cytostatic effect in the treatment of a few benign cancers which results in tumors re-growth. In order to overcome these limitations, we have looked for a novel potential small molecule mTORC1 allosteric inhibitor by in silico and in vitro methods. Firstly, we carried out the in silico selection using Virtual Ligand Screening (VLS) for 105 compounds to select ligands with the high calculated scores toward FRB/FKBP12 interface as a receptor (PDB ID: 1fap). After further score calculations, we selected the top 5 compounds for the next selection step. We also prepared FKBP-rapamycin binding domain (FRB) of the mTORC1 and FKBP12, by using pET15b expression vector and BL21(DE3) E. coli. For the molecular-level protein: protein interaction (PPI) measurement, we used AlphaLISATM system (PerkinElmer, USA) using the prepared proteins. In addition, we checked the kinase activity using AlphaLISA® p-P70 S6K (T389) assay kit (PerkinElmer, USA), as well as Western blotting against p-S6 (S235/236) and p-4E-BP1 (T37/46). Finally, we performed the cell cytotoxicity assay of the selected compound against cancer and noncancer cell lines. The docking simulations showed that the residues involved in the interaction between FRB/FKBP12 binding site and rapamycin are partially overlapped with those of the screened compounds which stabilized the formation of FRB:Ligand:FKBP12 ternary complex. We also measured the inhibitory effect of the selected compounds against the ternary complex formation by rapamycin and two of them, ZNC1 and ZNC5, showed interactivity by IC50 of 30 nM and 41 nM, respectively. On the other hand, only ZNC5 promoted the formation of the ternary complex by a KD value of 1.7 nM. In addition, ZNC5 inhibited the kinase activity not only in the starvation condition by IC50 of 1.2 nM but also in the feeding-induced mTORC1 activation condition with IC50 of 3.5 nM. Moreover, it has been observed that the ZNC5 inhibited kinase activity of mTORC1 in the cancer cells while no effect on the normal cells. In this study, we discovered the ZNC5, a new allosteric inhibitor to the kinase of mTORC1, through the in silico and in vitro hybrid selection. The smaller size of ZNC5 comparing to rapamycin is probably advantageous for better pharmacokinetics in vivo. Most importantly, ZNC5 specifically inhibited the growth of cancer cells over normal cells, while no such specificity observed by rapamycin. Citation Format: Raef Shams, Yoshihiro Ito, Hideyuki Miyatake. A discovery of a small molecule mTORC1 allosteric inhibitor targeting cancer cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 662.

Abstract 345: Altered ALDH1A1 expression and cellular copper levels between low and highly metastatic osteosarcoma provides a case for novel repurposing of disulfiram

Abstract Osteosarcoma (OS) is the most common primary bone cancer and disproportionately affects pediatric and adolescent patients. Survival rates for OS patients with metastatic disease is only 15-30% and has not improved in several decades. Novel treatments targeting specifically metastatic markers of OS are needed. ALDH1A1 is a known cancer stem marker and highly expressed in metastatic cancer cells. Disulfiram (Antabuse®) is an FDA-approved anti-alcoholism drug which acts as an ALDH inhibitor and has been widely studied for repurposing as an effective therapy in multiple types of cancer. Disulfiram cytotoxicity in cancer cells has been shown to be copper-dependent due to its ability to function as a bivalent metal ion chelator of copper (Cu). Cu concentrations of OS patient tumors, human OS cell lines, and OS patient plasma were determined using a Perkin Elmer AAnalyst 600 atomic absorption spectrophotometer. qPCR using custom primers for ALDH1A1 was performed on human OS cell lines and OS patient tumors differing in metastatic potential. OS cell cytotoxicity assays were performed with disulfiram and copper chloride after 24 hours of treatment. Balb/C mice were challenged intratibial with Luciferase+ K7M2, and treated with disulfiram and copper gluconate by oral gavage. Primary tumor growth and pulmonary metastases were monitored using the IVIS XR live imaging system. Metastatic OS patient tumors displayed significantly increased ALDH1A1 expression compared to non-metastatic OS patient tumors (n=8, P=0.02). Metastatic OS tumors displayed decreased Cu levels compared to non-metastatic OS tumors (n=18, P=0.05). Conversely, serum Cu levels from OS patients with metastases demonstrated increased blood Cu levels compared with non-metastatic patients (n=24, P=0.01). qPCR displayed ALDH1A1 expression was significantly increased in highly metastatic human OS cell lines LM2 and LM7 compared to low metastatic SaOS-2 (n=3, P=0.002). Intracellular Cu was inversely proportional to metastatic phenotype in human OS cell lines SaOS-2>LM2>LM7. Copper chloride displayed clear potentiation of disulfiram resulting in a strong cytotoxic effect in both SaOS-2 and LM7. Doxorubicin IC50 for SaOS-2 and LM7 was 1.2 µM and 2.5 µM respectively, while disulfiram IC50 with a 50 nM copper chloride supplement for SaOS-2 and LM7 was 1.2 µM and 0.6 µM respectively. In our preclinical mouse model, after primary tumor resection, differences in recurrent growth at amputation site were seen between treatment groups. Disulfiram and copper gluconate combination treated mice displayed 13% (1/8) recurrence rates at the primary tumor amputation site, while untreated animals displayed 60% (9/15) recurrence rates. This study demonstrates that both ALDH1A1 and Cu bioavailability are altered between low and highly metastatic OS. Since ALDH1A1 is a direct target and Cu is a potentiator of disulfiram, this supports the potential of using this repurposed drug in combination with surgical and chemotherapy interventions for metastatic OS. Citation Format: Jonathan B. Mandell, Nerone Douglas, Vrutika Ukani, Carolyn Anderson, Jan Beumer, Rebecca Watters, Kurt Weiss. Altered ALDH1A1 expression and cellular copper levels between low and highly metastatic osteosarcoma provides a case for novel repurposing of disulfiram [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 345.

Chrysin Suppresses HT-29 Cell Death Induced by Diclofenac through Apoptosis and Oxidative Damage

Background Diclofenac (Dic) was shown to increase in reactive oxygen species (ROS) levels thereby resulting oxidative stress and apoptotic cell death in colon cancer. The antioxidants can prevent and repair oxidative damage caused by ROS. The aim of this study was to assess the effect of chrysin (Chr) on Dic-induced toxicity in HT-29 and molecular mechanisms underlying its effect. Methods Cell proliferation and cytotoxicity assays were carried out by WST-1 and LDH leakage assay, apoptotic index was calculated by TUNEL Assay, antioxidant parameters were studied by measurement of ROS, LPO and TAS levels and catalase activity, expression of caspase-3 protein levels were analyzed by immunohistochemical staining, mRNA levels of apoptotic and anti-apoptotic genes were studied by qRT-PCR. Results The cellular processes of Dic-triggered cell death was associated with increase in ROS, malondialdehyde levels and lactate dehydrogenase release, decrease in total antioxidant and catalase activity while pretreatment with Chr reversed these effects. The expression level of p53, cas-3, cas-8, Bax and cytochrome c increased in Dic-exposed group while they were reduced by Chr. Conclusion The use of antioxidant nutritional supplements, and in particular of Chr, may reduce the efficacy of Dic in inducing apoptosis of colon cancer cells.

Gut bacteria of Varanus salvator possess potential antitumour molecules.

Pollution, unhygienic conditions and organic waste are detrimental to human health. On the contrary, animals living in polluted environments, feeding on organic waste and exposed to noxious agents such as heavy metals must possess remarkable properties against contracting diseases. Species such as cockroaches and water monitor lizards thrive in unhygienic conditions and feed on decaying matter. Here, we investigated the antitumour properties of metabolites produced by gut bacteria isolated from Varanus salvator (Asian water monitor lizard). An adult water monitor lizard and a juvenile water monitor lizard were acquired, and dissected. Their aerobic gut bacteria were isolated and identificated through 16S rDNA sequencing. Next, bacterial conditioned media (CM) were prepared and utilised for subsequent assays. Growth inhibition, MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell viability assay, cytotoxicity and cell survival assays were accomplished against a panel of cancer cells as well as a normal cell line. Furthermore, liquid chromatography-mass spectrometry (LC-MS) was employed to identify potential antitumour molecules. A plethora of bacteria were isolated from the gut of juvenile and adult V. salvator respectively. Moreover, CM prepared from selected bacteria exhibited antitumour activity. Of note, LC-MS results indicated the presence of several molecules with reported antitumour activity, namely, 3-butylidene-7-hydroxyphthalide, C75, enigmol, estrone 16-oxime, proglumide and S-allyl-L-cysteine. Furthermore, 356 potentially novel molecules from juvenile V. salvator and 184 from adult V. salvator were depicted. Thus, the gut microbiota of V. salvator might be considered as a great niche of antitumour molecules; however, further in vitro and in vivo studies are needed to assess the antitumour properties of these molecules.

Curcumin preconditioned human adipose derived stem cells co-transplanted with platelet rich plasma improve wound healing in diabetic rats

AimInflammatory and oxidative microenvironment at diabetic’ wound site hinder the therapeutic efficacy of cell-based therapies in diabetic patients. The purpose of this study is to explore the competence of curcumin preconditioned human adipose derived cells (hASCs) in combination with platelet rich plasma (PRP) for the repair of wounds in diabetic rats. Main methodsThe cytoprotective effect of curcumin preconditioning for hASCs against hyperglycemic stress was evaluated through analysis of cell morphology, viability, cytotoxicity, senescence, and scratch wound healing assays. Subsequently, the healing capacity of curcumin preconditioned hASCs (Cur-hASCs) added to PRP was examined in excisional wounded diabetic rat model. Healed skin biopsies were excised to analyze gene and protein expression of wound healing markers by qPCR and western blotting. Histopathological changes were observed through hematoxylin and eosin staining. Key findingsWe found that Cur-hASCs counteract the glucose stress much better than non-preconditioned hASCs by maintaining their cellular morphology and viability as well as metabolic potential. Further in vivo results revealed that, Cur-hASCs co-injected with PRP resulted in faster wound closure, improved fibroblast proliferation, increased neovascularization, marked reduction in inflammatory cells, and compact extracellular matrix with completely covered thick epithelium. Moreover, Cur-hASCs + PRP treatment significantly improved the expression of key healing markers such as pro-angiogenic (Vegf), dermal matrix deposition (Col1α1), cell migration (bFgf) and cell proliferation (Pcna) at wound site. SignificanceOur findings propose a combinatorial therapy (Cur-hASCs + PRP) as a novel modality to improve the efficacy of hASCs-based therapy for diabetic wounds.

Detection, transformation, and toxicity of indole-derivative nonsteroidal anti-inflammatory drugs during chlorine disinfection

As important emerging contaminants, nonsteroidal anti-inflammatory drugs (NSAIDs) are the most intensively prescribed pharmaceuticals introduced to drinking water due to their incomplete removal in wastewater treatment. While concentrations of NSAIDs in drinking water are generally low, they have been attracting increasing concern as a result of their disinfection byproducts (DBPs) generated in drinking water disinfection. In this work, detection methods were set up for four representative indole-derivative NSAIDs (indomethacin, acemetacin, sulindac, and etodolac) using ultra performance liquid chromatography/electrospray ionization-triple quadruple mass spectrometry (UPLC/ESI-tqMS). ESI+ was better for detection of indomethacin and sulindac, whereas ESI− was suitable to detection of acemetacin and etodolac. With optimized MS parameters, the instrument detection and quantitation limits of the four indole derivatives were achieved to be 1.1–24.6 ng/L and 3.7–41.0 ng/L, respectively. During chlorination, indomethacin and acemetacin could undergo five major reaction types (chlorine substitution, hydrolysis, decarboxylation, C–C coupling, and C–N cleavage) to form a series of DBPs, among which 19 were proposed/identified with structures. Based on the revealed structures of DBPs, transformation pathways of indomethacin and acemetacin in chlorination were partially elucidated. Notably, individual and mixture toxicity of indomethacin and acemetacin before/after chlorination were evaluated using a well-established acute toxicity assessment and a Hep G2 cell cytotoxicity assay, respectively. Results showed that the predicted acute toxicity of a few chlorination DBPs were higher than their precursors; chlorination substantially enhanced the mixture cytotoxicity of indomethacin by over 10 times and slightly increased the mixture cytotoxicity of acemetacin.

Osteogenesis of adipose-derived stem cells from patients with glucose metabolism disorders

BackgroundAdipose derived stem cells (ADSCs) are clinically widely used somatic stem cells obtained from white adipose tissue. They are characterized by ability to differentiate e.g. into osteoblasts and might successfully regenerate bone tissue in fracture repair. However, the main problem of somatic stem cells is a documented influence of various diseases, drugs or age which can inhibit cells activity. Therefore, in the present study, we investigated the influence of insulin resistance (IR) and type 2 diabetes (T2D) on the proliferation and differentiation potential of ADSCs.MethodsThe fat from subcutaneous abdominal adipose tissue was acquired by lipoaspiration from 23 voluntary participants, divided into three groups: with diabetes type 2, with insulin resistance and control healthy donors. The proliferative potential was analyzed by cell cytotoxicity assays and by mRNA expression of genes connected with proliferation. Flow cytometry was done for identifying proteins characteristic for mesenchymal stem cells and an analysis of osteogenic differentiation potential based on the assessment of osteogenic markers by real time RT-qPCR, and the evaluation of calcium deposition were also performed.ResultsThe results showed that diabetes type 2 lowered the activity of ADSCs in proliferation assays and changed their phenotypical characteristics. Interestingly, we observed differences in the proliferation potential of ADSCs in patients with insulin resistance, which is often the first phase of diabetes, compared to the control. It might suggest that insulin resistance, early-stage T2D, alters the activity of cells. Moreover, expression of osteogenesis markers was higher in cells from T2D patients than in cells from patients with IR and control.ConclusionWe conclude that type 2 diabetes changes the activity of stem cells, and insulin resistance influences on the proliferation of ADSCs.

Optimized High-Contrast Brightfield Microscopy Application for Noninvasive Proliferation Assays of Human Cell Cultures.

High-contrast brightfield (HCBF) microscopy has emerged as a strong tool for noninvasive counting of cells in culture. HCBF imaging delivers precise cell growth data and is completely label free rendering it an attractive alternative to common cell counting procedures that often adversely affect cell growth. With computational image analysis, HCBF achieves efficient high-throughput automated workflows, extremely relevant for drug and chemical screens in pharmaceutical, toxicological, and biomedical research. We demonstrate the applicability of HCBF microscopy to count three common cell types (HEK293, Huh7, and primary human dermal fibroblasts) with diverse morphology challenging the method. The three cell types required different analysis settings, and we identified two parameters of the computational image analysis, which after cell-specific optimization significantly improved the cell counting accuracy, namely the lower size limit and the intensity threshold. Three-dimensional (3D) imaging approaches, which have obtained great attention in recent years, were an interesting prospect to combine with HCBF microscopy. We optimized the analysis of two 3D outputs but found 3D HCBF imaging to be inferior to the optimized single-layer HCBF imaging for cell counting. HCBF cell counts were highly linearly correlated with (R2 > 0.99) and highly similar (<15% difference) to cell counts obtained through Hoechst staining, over a broad range of densities allowing at least this level of accuracy for two to three cell generations in Huh7 cells and fibroblasts. Counts of HEK293 cells correlated somewhat less. In conclusion, the HCBF cell counting method is excellently suited for cell proliferation assays and cytotoxicity assays.

Synthesis of Aptamer-PEI-g-PEG Modified Gold Nanoparticles Loaded with Doxorubicin for Targeted Drug Delivery.

Due to drug resistance and toxicity in healthy cells, use of doxorubicin (DOX) has been limited in clinical cancer therapy. This protocol describes the designing of poly(ethylenimine) grafted with polyethylene glycol (PEI-g-PEG) copolymer functionalized gold nanoparticles (AuNPs) with loaded aptamer (AS1411) and DOX through amide reactions. AS1411 is specifically bonded with targeted nucleolin receptors on cancer cells so that DOX targets cancer cells instead of healthy cells. First, PEG is carboxylated, then grafted to branched PEI to obtain a PEI-g-PEG copolymer, which is confirmed by 1H NMR analysis. Next, PEI-g-PEG copolymer coated gold nanoparticles (PEI-g-PEG@AuNPs) are synthesized, and DOX and AS1411 are covalently bonded to AuNPs gradually via amide reactions. The diameter of the prepared AS1411-g-DOX-g-PEI-g-PEG@AuNPs is ~39.9 nm, with a zeta potential of -29.3 mV, indicating that the nanoparticles are stable in water and cell medium. Cell cytotoxicity assays show that the newly designed DOX loaded AuNPs are able to kill cancer cells (A549). This synthesis demonstrates the delicate arrangement of PEI-g-PEG copolymers, aptamers, and DOX on AuNPs that are achieved by sequential amide reactions. Such aptamer-PEI-g-PEG functionalized AuNPs provide a promising platform for targeted drug delivery in cancer therapy.

Hyaluronic acid targeted and pH-responsive nanocarriers based on hollow mesoporous silica nanoparticles for chemo-photodynamic combination therapy

In this work, a pH-responsive and tumor targeted multifunctional drug delivery system (RB-DOX@HMSNs-N = C-HA) was designed to realize chemo-photodynamic combination therapy. Hollow mesoporous silica nanoparticles (HMSNs) was served as the host material to encapsulate doxorubicin (DOX) and photosensitizer rose bengal (RB). Hyaluronic acid (HA) was modified on the surface of HMSNs via pH-sensitive Schiff base bonds as gatekeeper as well as targeted agent. Characterization results indicated the successful preparation of HMSNs-N = C-HA with appropriate diameter of 170 nm around and the nanocarriers displayed superior drug loading capacity (15.30 % for DOX and 12.78 % for RB). Notably, the results of in vitro drug release experiments confirmed that the system possessed good pH-sensitivity, which made it possible to release cargoes in slight acid tumor micro-environments. Significantly, the in vitro cell uptake and cytotoxicity assay results fully proved that RB-DOX@HMSNs-N = C-HA could precisely target murine mammary carcinoma (4T1) cells and effectively inhibit tumor cells viability with chemo-photodynamic synergistic therapy. Overall, our work (RB-DOX@HMSNs-N = C-HA) provides an efficient approach for the development of chemo-photodynamic combination therapy.

Fabrication of Poly(ethylene glycol) Capsules via Emulsion Templating Method for Targeted Drug Delivery.

To reduce nonspecific interactions and circumvent biological barriers, low-fouling material of poly(ethylene glycol) (PEG) is most used for the modification of drug nanocarriers. Herein, we report the fabrication of PEG capsules via the free-radical polymerization of linear PEG or 8-arm-PEG using an emulsion templating method for targeted drug delivery. Doxorubicin (DOX) could be loaded in capsules via electrostatic interactions. The obtained capsules composed of 8-arm-PEG result in a lower cell association (2.2%) compared to those composed of linear PEG (7.3%) and, therefore, demonstrate the stealth property. The functionalization of cyclic peptides containing Arg-Gly-Asp (cRGD) on PEG capsules induce high cell targeting to U87 MG cells. A cell cytotoxicity assay demonstrates the biocompatibility of PEG capsules and high drug delivery efficacy of the targeted capsules. The reported capsules with the stealth and targeting property provide a potential platform for improved drug delivery.