3T3 Mouse Fibroblast Cells Research Articles

Natural compounds as angiogenic enzyme thymidine phosphorylase inhibitors: In vitro biochemical inhibition, mechanistic, and in silico modeling studies.

Natural flora is the richest source of novel therapeutic agents due to their immense chemical diversity and novel biological properties. In this regard, eighteen natural products belonging to different chemical classes were evaluated for their thymidine phosphorylase (TP) inhibitory activity. TP shares identity with an angiogenic protein platelet derived endothelial cell growth factor (PD-ECGF). It assists tumor angiogenesis and is a key player in cancer progression, thus an ideal target to develop anti-angiogenic drugs. Eleven compounds 1–2, 5–10, 11, 15, and 18 showed a good to weak TP inhibitory activity (IC50 values between 44.0 to 420.3 μM), as compared to standards i.e. tipiracil (IC50 = 0.014 ± 0.002 μM) and 7-deazaxanthine (IC50 = 41.0 ± 1.63 μM). Kinetic studies were also performed on active compounds, in order to deduce the mechanism of ligand binding to enzyme. To get further insight into receptor protein (enzyme) and ligand interaction at atomic level, in- sillico studies were also performed. Active compounds were finally evaluated for cytotoxicity test against mouse fibroblast (3T3) cell line. Compound 18 (Masoprocol) showed a significant TP inhibitory activity (IC50 = 44.0 ± 0.5 μM). Kinetic studies showed that it inhibits the enzyme in a competitive manner (Ki = 25.6 ± 0.008 μM), while it adopts a binding pose different than the substrate thymidine. It is further found to be non-toxic in MTT cytotoxicity assay. This is the first report on TP inhibitory activity of several natural compounds, some of which may serve as leads for further research towards drug the development.

Carbazole‐Linked 1,2,3‐Triazoles: In Vitro β‐Glucuronidase Inhibitory Potential, Kinetics, and Molecular Docking Studies

Abstractβ‐Glucuronidase enzyme is a tetrameric glycoprotein present in microsomes and lysosomes of many organs, and body fluids. Over‐expression of this enzyme is observed in several melanomas and carcinomas. Therefore, it has been identified as a target for the treatment of several pathological conditions. In this regard, carbazole linked 1,2,3‐triazoles (1–27) were synthesized according to our previous report, and evaluated for their in vitro β‐glucuronidase inhibitory activities. Compounds 7–10, 17–18, 20, and 22–27 showed potent activities with IC50 values between 0.55–32.5 μM, as compared to the standard, D‐saccharic acid 1,4‐lactone (IC50=45.75 ± 2.16 μM). All active compounds were found to be non‐cytotoxic against mouse fibroblast 3T3 cell line. Compounds 20, 22, 23, 25, 26, and 27 were subjected to enzyme kinetic studies for the determination of their modes of inhibition, and dissociation constants Ki. Compounds 23, 25, and 26 were also studied for their mode of inhibition by using molecular docking methods.

Systematic investigation of in vitro and in vivo safety, toxicity and degradation of mesoporous silica nanoparticles synthesized using commercial sodium silicate

Abstract Mesoporous silica nanoparticles (MSNs) have been extensively investigated as drug delivery carriers due to their unique properties. Although MSNs synthesized using a very economic source of silica, sodium silicate, are promising carriers for drug delivery, information regarding their biocompatibility and in vivo toxicity is scarce. In the present work, biocompatibility, toxicity profile and degradation of mesoporous silica nanoparticles synthesized using commercial sodium silicate have been studied. In vitro degradation studies confirmed that MSNs got degraded to silicic acid within 6 days in PBS 7.4 The synthesized MSNs were found to be biocompatible to different cell lines such as human embryonic kidney (HEK-293) cells, human caucasian colon adenocarcinoma (Caco-2) cells, human liver carcinoma (HepG2) cells and mouse fibroblast (3T3) cells with greater than 90% cell viability at concentration of 200 μg/mL. They did not cause significant hemolysis (only 1.87%) up to 200 μg/mL concentration when incubated for 2 h with chicken red blood cells. Furthermore, hematological and biochemical tests of blood samples as well as histopathological examinations of tissues after MSN injection, confirmed that the MSNs were well tolerated by mice up to 40 mg/kg. Injected MSNs were completely excreted out through urine and feces by rats (injected intravenously with 20 mg/kg of MSNs) within 4 days in form of silicic acid.

Cryoprotectant-free cryopreservation of mammalian cells by superflash freezing

Cryopreservation is widely used to maintain backups of cells as it enables the semipermanent storage of cells. During the freezing process, ice crystals that are generated inside and outside the cells can lethally damage the cells. All conventional cryopreservation methods use at least one cryoprotective agent (CPA) to render water inside and outside the cells vitreous or nanocrystallized (near-vitrification) without forming damaging ice crystals. However, CPAs should ideally be avoided due to their cytotoxicity and potential side effects on the cellular state. Herein, we demonstrate the CPA-free cryopreservation of mammalian cells by ultrarapid cooling using inkjet cell printing, which we named superflash freezing (SFF). The SFF cooling rate, which was estimated by a heat-transfer stimulation, is sufficient to nearly vitrify the cells. The experimental results of Raman spectroscopy measurements, and observations with an ultrahigh-speed video camera support the near-vitrification of the droplets under these conditions. Initially, the practical utility of SFF was demonstrated on mouse fibroblast 3T3 cells, and the results were comparable to conventional CPA-assisted methods. Then, the general viability of this method was confirmed on mouse myoblast C2C12 cells and rat primary mesenchymal stem cells. In their entirety, the thus-obtained results unequivocally demonstrate that CPA-free cell cryopreservation is possible by SFF. Such a CPA-free cryopreservation method should be ideally suited for most cells and circumvent the problems typically associated with the addition of CPAs.

Zinc-oxide nanoparticles act catalytically and synergistically with nitric oxide donors to enhance antimicrobial efficacy.

The development of infection-resistant materials is of substantial importance as seen with an increase in antibiotic resistance. In this project, the nitric oxide (NO)-releasing polymer has an added topcoat of zinc oxide nanoparticle (ZnO-NP) to improve NO-release and match the endogenous NO flux (0.5-4 × 10-10 mol cm-2 min-1 ). The ZnO-NP is incorporated to act as a catalyst and provide the additional benefit of acting synergistically with NO as an antimicrobial agent. The ZnO-NP topcoat is applied on a polycarbonate-based polyurethane (CarboSil) that contains blended NO donor, S-nitroso-N-acetylpenicillamine (SNAP). This sample, SNAP-ZnO, continuously sustained NO release above 0.5 × 10-10 mol cm-2 min-1 for 14 days while samples containing only SNAP dropped below physiological levels within 24 h. The ZnO-NP topcoat improved NO release and reduced the amount of SNAP leached by 55% over a 7-day period. ICP-MS data observed negligible Zn ion release into the environment, suggesting longevity of the catalyst within the material. Compared to samples with no NO-release, the SNAP-ZnO films had a 99.03% killing efficacy against Staphylococcus aureus and 87.62% killing efficacy against Pseudomonas aeruginosa. A cell cytotoxicity study using mouse fibroblast 3T3 cells also noted no significant difference in viability between the controls and the SNAP-ZnO material, indicating no toxicity toward mammalian cells. The studies indicate that the synergy of combining a metal ion catalyst with a NO-releasing polymer significantly improved NO-release kinetics and antimicrobial activity for device coating applications. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 00A: 000-000, 2019.

Bioinformatics: A rational combine approach used for the identification and in-vitro activity evaluation of potent β-Glucuronidase inhibitors

Identification of hotspot drug-receptor interactions through in-silico prediction methods (Pharmacophore mapping, virtual screening, 3DQSAR, etc), is considered as a key approach in drug designing and development process. In the current design study, advanced in-silico based computational techniques were used for the identification of lead-like molecules against the targeted receptor β-glucuronidase. The binding pattern of a potent inhibitor in the ligand-receptor X-ray co-crystallize complex was used to identify and extract the structure-base Pharmacophore features. Based on these observations; five structure-based pharmacophore models were derived to conduct the virtual screening of ICCBS in-house data-base. Top-ranked identified Hits (33 compounds) were selected to subject for in-vitro biological activity evaluation against β-glucuronidase enzyme; out of them, twenty compounds (61% of screened compounds) evaluated as actives, however eleven compounds were found to have significantly higher inhibitory activity, including compounds 1, 5–8, 10, 12–13, and 17–19 with IC50 values ranging from 1.2 μM to 34.9 μM. Out of the eleven potent inhibitors, seven compounds 1, 5, 6, 7, 8, 13, and 19 were found new, and evaluated first time for the β-glucuronidase inhibitory activity. Compounds 1, 5 and 19 exhibited a highly potent inhibition in uM of β-glucuronidase enzyme with non-cytotoxic behavior against the mouse fibroblast (3T3) cell line. Our combined in-silico and in-vitro results revealed that the binding pattern analysis of the eleven potent inhibitors, showed almost similar non-covalent interactions, as observed in case of our validated pharmacophore model. The obtained results thus demonstrated that the virtual screening minimizes false positives, and provide a template for the identification and development of new and more potent β-glucuronidase inhibitors with non-toxic effects.

Thymol enriched bacterial cellulose hydrogel as effective material for third degree burn wound repair

Bacterial cellulose is well known for its excellent contributions in biomedical applications due to its superior properties. However the lack of antimicrobial property restricts its use in wound healing. To address the complications in third degree burns, thymol enriched bacterial cellulose hydrogel (BCT) was developed in this study. The incorporation of thymol into bacterial cellulose along with its chemical and thermal changes were investigated by FTIR, TGA and DSC respectively. Antimicrobial studies revealed that BCT possess excellent biocidal activity against burn specific pathogens. The in vitro biocompatibility studies were carried out in mouse 3T3 fibroblast cells. The BCT hydrogel facilitated the growth of fibroblast cells, exhibiting low toxicity, and increased cell viability. The burn wound healing efficiency of the BCT hydrogel was examined in vivo using female albino Wistar rats. Histopathological studies reveal that the wound treated with BCT hydrogel showed faster wound closure than BC and control groups. All these findings, suggest that BCT hydrogel can be used as resourceful and natural burn wound dressing material.

Pre-validation study of alternative developmental toxicity test using mouse embryonic stem cell-derived embryoid bodies

The embryoid body test (EBT) is a developmental toxicity test method that assesses the half inhibitory concentrations of substances in the area of embryoid bodies (EBs), and in the viability of mouse embryonic stem cells (ESCs) and fibroblasts (3T3 cells) following chemical exposure for three and four days, respectively. In the previous study, the EBT showed more advanced than the embryonic stem cell test (EST) from the European Centre for the Validation of Alternative Methods (ECVAM) applying cardiac differentiation of mouse ESCs, because the EBT greatly reduced the exposure time, labor, and amount of materials required, and misclassification of embryotoxic potential. This pre-validation study evaluated the predictive accuracy of the EBT using 26 coded test substances by two steps: intra-laboratory and inter-laboratory reproducibility tests. Since some substances have different embryotoxic potentials at different pregnancy periods, in this study, a new prediction model consisting of non-toxic and toxic classes was used, instead of the existing prediction model assessing embryotoxicants in four classes. The results of the intra- and inter-laboratory tests were highly accurate (above 80%) when substances were classified using the predictive model. In conclusion, EBT can accurately classify various embryotoxicants in a short time with less effort and greater validation.

Preliminary study on conjugation of formononetin with multiwalled carbon nanotubes for inducing apoptosis via ROS production in HeLa cells.

BackgroundThe present work was conducted to prepare and evaluate multiwalled carbon nanotube–formononetin (MWCNT-FMN) composite for sustained delivery and inducing apop-tosis via reactive oxygen species (ROS) production in HeLa cells.MethodsThe composite was prepared by solution mixing with short carboxylic group-functionalized multiwalled carbon nanotubes (MWCNT-COOH). Then the composite was characterized by laser particle size analysis, Fourier transform infrared spectrometry, X-ray diffractometry, differential scanning calorimetry, and scanning electron microscopy. Drug release rates in vitro were determined by dialysis method. The in vitro cytotoxicity study was performed using water soluble tetrazolium assay. The cellular apoptosis assay, ROS, and mitochondrial membrane potential (MMP) of HeLa cells were investigated by acridine orange and ethidium bromide double dye, 2′,7′-dichlorodihydrofluorescein diacetate, and 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine iodide probe, respectively.ResultsThe entrapment efficiency was 28.77%±0.15%, and the loading capacity was 12.05%±0.20%. The release of MWCNT-FMN was sustained, and the cumulative release rate of formononetin (FMN) from MWCNT-COOH was higher at pH 7.4 than at pH 5.3. The in vitro cytotoxicity assay demonstrated that FMN, MWCNT-COOH, and MWCNT-FMN had no significant effects on the proliferation and viability of mouse fibroblast 3T3 cells over 48 hours, while the cell growth inhibition of the three samples showed concentration-dependent for HeLa cells. Biological assay suggested FMN and MWCNT-FMN could induce apoptosis in HeLa cells, meanwhile the cells exhibited stronger ROS signal and more depolarized MMP than that of the control group.ConclusionThese results preliminarily demonstrated that MWCNT-FMN exerted anticancer efficacy through cellular apoptosis induced by ROS-mediated mitochondrial dysfunctions in HeLa cells.

Human adipose-derived stem cells support the growth of limbal stem/progenitor cells.

The most efficient method to expand limbal stem cells (LSCs) in vitro for clinical transplantation is to culture single LSCs directly on growth-arrested mouse fibroblast 3T3 cells. To reduce possible xenobiotic contamination from 3T3s, primary human adipose-derived stem cells (ASCs) were examined as feeder cells to support the expansion of LSCs in vitro. To optimize the ASC-supported culture, freshly isolated limbal epithelial cells in the form of single cells (SC-ASC) or cell clusters (CC-ASC) were cultured using three different methods: LSCs seeded directly on feeder cells, a 3-dimensional (3D) culture system and a 3D culture system with fibrin (fibrin 3D). The expanded LSCs were examined at the end of a 2-week culture. The standard 3T3 culture served as control. Expansion of SC-ASC showed limited proliferation and exhibited differentiated morphology. CC-ASC generated epithelial cells with undifferentiated morphology in all culture methods, among which CC-ASC in 3D culture supported the highest cell doubling (cells doubled 9.0 times compared to cells doubled 4.9 times in control) while maintained the percentage of putative limbal stem/progenitor cells compared to the control. There were few cell-cell contacts between cultured LSCs and ASCs in 3D CC-ASC. In conclusion, ASCs support the growth of LSCs in the form of cell clusters but not in single cells. 3D CC-ASC could serve as a substitute for the standard 3T3 culture to expand LSCs.

Discriminating modes of toxic action in mice using toxicity in BALB/c mouse fibroblast (3T3) cells

The objective of this study was to determine whether toxicity in mouse fibroblast cells (3T3 cells) could predict toxicity in mice. Synthesized data on toxicity was subjected to regression analysis and it was observed that relationship of toxicities between mice and 3T3 cells was not strong (R2 = 0.41). Inclusion of molecular descriptors (e.g. ionization, pKa) improved the regression to R2 = 0.56, indicating that this relationship is influenced by kinetic processes of chemicals or specific toxic mechanisms associated to the compounds. However, to determine if we were able to discriminate modes of action (MOAs) in mice using the toxicities generated from 3T3 cells, compounds were first classified into “baseline” and “reactive” guided by the toxic ratio (TR) for each compound in mice. Sequence, binomial and recursive partitioning analyses provided strong predictions of MOAs in mice based upon toxicities in 3T3 cells. The correct classification of MOAs based on these methods was 86%. Nearly all the baseline compounds predicted from toxicities in 3T3 cells were identified as baseline compounds from the TR in mice. The incorrect assignment of MOAs for some compounds is hypothesized to be due to experimental uncertainty that exists in toxicity assays for both mice and 3T3 cells. Conversely, lack of assignment can also arise because some reactive compounds have MOAs that are different in mice compared to 3T3 cells. The methods developed here are novel and contribute to efforts to reduce animal numbers in toxicity tests that are used to evaluate risks associated with organic pollutants in the environment.

Frutapin, a lectin from Artocarpus incisa (breadfruit): cloning, expression and molecular insights.

Artocarpus incisa (breadfruit) seeds contain three different lectins (Frutalin, Frutapin (FTP) and Frutackin) with distinct carbohydrate specificities. The most abundant lectin is Frutalin, an α-D-galactose-specific carbohydrate-binding glycoprotein with antitumour properties and potential for tumour biomarker discovery as already reported. FTP is the second most abundant, but proved difficult to purify with very low yields and contamination with Frutalin frustrating its characterization. Here, we report for the first time high-level production and isolation of biologically active recombinant FTP in Escherichia coli BL21, optimizing conditions with the best set yielding >40 mg/l culture of soluble active FTP. The minimal concentration for agglutination of red blood cells was 62.5 µg/ml of FTP, a process effectively inhibited by mannose. Apo-FTP, FTP–mannose and FTP–glucose crystals were obtained, and they diffracted X-rays to a resolution of 1.58 (P212121), 1.70 (P3121) and 1.60 (P3121) Å respectively. The best solution showed four monomers per asymmetric unit. Molecular dynamics (MD) simulation suggested that FTP displays higher affinity for mannose than glucose. Cell studies revealed that FTP was non-cytotoxic to cultured mouse fibroblast 3T3 cells below 0.5 mg/ml and was also capable of stimulating cell migration at 50 µg/ml. In conclusion, our optimized expression system allowed high amounts of correctly folded soluble FTP to be isolated. This recombinant bioactive lectin will now be tested in future studies for therapeutic potential; for example in wound healing and tissue regeneration.

Studies on new urease inhibitors by using biochemical, STD-NMR spectroscopy, and molecular docking methods

Discovery of new urease inhibitors is an important approach towards the treatment of diseases caused by ureolytic bacteria. Urease has an important role in several pathologies, such as urolithiasis, peptic and duodenal ulcers, etc. In this regard, urease inhibitory activity of heterocyclic synthetic compounds 1–14, belonging to different chemical classes was evaluated by employing in vitro biochemical assay, and saturation transfer difference-NMR technique. Compounds 1, 3–5, 7, 10, and 12 have shown urease inhibitory potential in vitro. Among them, compound 1 was found to be more potent (IC50 of 12.90 ± 0.63 µM) than a clinical drug, acetohydroxamic acid (IC50 = 41.5 ± 1.50 µM) (Standard). Compounds 3 (IC50 = 15.0 ± 1.10 µM), 4 (IC50 = 24.67 ± 2.87 µM), and 5 (IC50 = 25.50 ± 0.63 µM) were also identified as potent inhibitors of urease enzyme. These compounds showed strong interactions with the urease enzyme (receptor) in saturation transfer difference-NMR spectra. Specifically, aromatic protons of active compounds received maximum Rf saturation from the receptor protein, thus were inferred to be as in close proximity to the protein. New inhibitors identified through biochemical assay and saturation transfer difference-nuclear magnetic resonance techniques were then subjected to kinetic and molecular docking studies to investigate their mode of inhibition, and production of their interactions with the protein at atomic level, respectively. Active compounds were found to be non-cytotoxic against mouse fibroblast (3T3) cell line MTT assay. Present study thereby identifies new inhibitors of urease enzyme in vitro as leads for further investigation towards the development of novel mechanism-based urease inhibitors.

Discovery of Organosulfur Compounds as Promising Antiglycation Agents with Non-Toxic Nature Against Mouse Fibroblast 3T3 Cells

Protein glycation is one of the major causes of diabetic complications while antiglycation therapy is the most important intervention to manage diabetic complications.  Currently, sulfur-containing compounds are under extensive studies due to their vast pharmacological applications particularly, against diabetic mellitus and oxidative stress induced pathological disorders.Present study is an effort to evaluate various classes of organosulfur compounds to explore promising inhibitors against protein glycation with enhanced antiglycation potential and low toxic effects. A library of organosulfur compounds belonging to different classes was investigated for their potential inhibition against protein glycation in vitro while MTT assay on mouse fibroblast 3T3 cells was used to assess the potential cytotoxicity of most promising antiglycation agents.On antiglycation assay, eight organosulfur compounds (1-8) exhibited a potent antiglycation activity with IC50 values (<16 µM), as compared to standard antiglycation agent rutin (IC50 = 98.01±2.03 µM). Similarly, compound (9) and compound (10) exhibited good antiglycation potential with IC50 values 591.6±1.53 and 401±1.20 µM, respectively. In this assay compounds (12-18) exhibited moderate antiglycation activity (47-62% inhibition) at 1mM concentration.On mouse fibroblast 3T3 cells cytotoxicity assay, all the tested compounds were found to be largely non-toxic with IC50 values (72.5-100) µM. In this assay, compound (10) exhibited slight toxic nature with IC50 value 5.00±1.89 as compared cycloheximide which is used as a standard in this assay with IC50 value 0.3 ± 0.089 μM.Key Words: Organosulfur compounds, diabetic complications, antiglycation agents, cytotoxicity assay

Evaluation of Extracted β-chitosan From Loligo duvauceli for the Preparation of Tissue Engineering Scaffolds

Over the years, there has been a growing need for producing cost effective, porous scaffold biomaterials for tissue engineering. Therefore, this study focused on fabrication of β-chitosan based scaffold from the waste of the pen of locally available squid variety Loligo duvauceli (Indian Squid). The scaffold was prepared by the solvent casting method which requires less time and minimum energy. To the best of our knowledge,there are no reports on scaffold preparation from the extracted β-chitosan. The biological properties of extracted chitosan scaffolds C(L) were evaluated and compared with those of commercial chitosan scaffold C(S). The prepared scaffolds were characterized by SEM, swelling property, in vitro enzymatic degradation, and hemo, biocompatibility properties. C(L) scaffolds had an average pore size of 60 µm and the swelling ratio was 16.2 ± 2.2% with mass loss percentage of 20.8 ± 4.5% after 4 weeks of degradation. It has exhibited good hemocompatible properties and thermal stability. Mouse fibroblast 3T3 cells were able to adhere and proliferate well in the extracted β-chitosan C(L) scaffold. All these results indicated that extracted β-chitosan C(L) is a suitable alternative for biomaterials used for tissue engineering purposes.

Tyrosine assisted size controlled synthesis of silver nanoparticles and their catalytic, in-vitro cytotoxicity evaluation.

A simple, green approach for the size controllable preparation of silver nanoparticles (SNPs) using tyrosine as reducing and capping agent is shown here. The size of SNPs is controlled by varying the pH of tyrosine solution. The as synthesized SNPs are characterized by using XRD, UV-Visible, DLS, TEM and SAED. Zeta potential measurements revealed the stability of tyrosine capped silver nanocolloids. Furthermore, catalytic activity studies concluded that the smaller SNPs acts as good catalyst and the catalytic activity depends on size of the nanoparticles. Further, the in-vitro cytotoxicity experiments concluded that the cytotoxicity of the prepared SNPs towards mouse fibroblast (3T3) cell lines is size and dose dependent. Additionally, the present approach is substitute to the traditional methods that are being used now-a-days for size controlled synthesis of SNPs.

Identification of natural products and their derivatives as promising inhibitors of protein glycation with non-toxic nature against mouse fibroblast 3T3 cells

<p>This study was performed to identify new inhibitors of protein glycation <em>in vitro</em>. Protein glycation is one of the major causes of late diabetic complications. In this study, terpenoids and alkaloids, isolated from different medicinal plants, along with their derivatives, were evaluated for their antiglycation activity <em>in vitro,</em> while MTT assay on mouse fibroblast 3T3 cells was used to assess their potential cytotoxicity. Among the tested compounds, gossypol (2,2′-<em>bis</em>-(formyl-1,6,7-trihydroxy-5-isopropyl-3-methylnaphthalene) (<strong>1</strong>), isolated from<em> Gossypium herbaceum, </em>and its derivatives,<em> </em>gossypol acetic acid (<strong>2</strong>), gossypolidene- 4-aminoantipyrine (<strong>4</strong>), and gazolidone (<strong>6</strong>), showed a potent antiglycation activity (IC<sub>50</sub> < 16 <em>µ</em>M), while gossypolidene-4-aminoantipyrine (<strong>5</strong>) showed a significant antiglycation activity with IC<sub>50 </sub>value 82.934±2.924<em> µ</em>M, in BSA-fluorescence assay. Alkaloid, noscapine (3S)-6,7-Dimethoxy-3-[(5R)-4-methoxy-6-methyl-5,6,7,8-tetrahy-dro-1,3-dioxolo[4,5-g]isoquinolin-5-yl] isobenzofuran-1(3<em>H</em>)-one (<strong>7</strong>), isolated from <em>Papaver somniferum, N</em>-nitrosoaphyllinic acid (<strong>9</strong>), a derivative of alkaloid aphylline<em>, </em>and 2<em>H</em>-quinolizine, octahydro salt (<strong>11</strong>), a salt of alkaloid lupinine, exhibited significant inhibition activity with<em> </em>IC<sub>50 </sub>values 152.662±5.432, 393.758 ±4.001 µM and 110.203±4.816µM, respectively. Similarly, compounds<strong> </strong>gossypolidene thiocarbamide (<strong>3</strong>), deoxypeganine hydrochloride (<strong>8</strong>)<strong>, </strong>lupinine (<strong>10</strong>) and cytisine (<strong>12</strong>) showed moderate inhibition with IC<sub>50</sub> values of 401.865 ±18.450, 863.322 ±6.415, 712.176±7.745, and 728.462±2.331<em> </em>µM, respectively. The results were compared with the standard antiglycation agent, rutin (<strong>13</strong>) (IC<sub>50 </sub>=98.012±2.030 µM).</p>Cellular cytotoxicity assay showed only gossypol acetic acid (<strong>2</strong>) and gossypolidene thiocarbamide (<strong>3</strong>) as somewhat toxic to 3T3 (mouse fibroblast) cells with IC<sub>50 </sub>values<em> </em>2.07 ±0.61 and 5.00 ±1.89 µM, respectively. Cycloheximide was used as a standard in this assay with IC<sub>50</sub> value 0.3 ± 0.089 μM

EVALUATION OF ANTIOXIDANT AND CYTOTOXIC PROPERTIES OF CYANOBACTERIA, LIMNOTHRIX SP. AND LEPTOLYNGBYA SP. FROM ARABIAN SEA

The hexane fractions of the marine cyanobacteria: Leptolyngbya sp. and Limnothrix sp., collected from Arabian Sea were found to display promising antioxidant properties than their ethyl acetate fraction during radical scavenging ABTS/DPPH assays (IC50=30/330 and 60/260 µg ml-1 respectively). Phytochemical analyses of the fractions indicated presence of carbohydrates, flavanoids and steroids in both organisms. The hexane fraction of Limnothrix sp exhibited higher UV-Vis (300-450 nm) absorption, indicating presence of aromatic antioxidant compounds like flavanoids. This fraction was relatively non-toxic towards mouse fibroblast 3T3 cells (IC50 400 µg ml-1) and in fact, protected live cells from UV induced intracellular reactive oxygen species (ROS) stress. On the contrary, the hexane fraction of Leptolyngbya sp. had lower UV-Vis absorption, richer in alkaloids and also more cytotoxic (IC50 200 µg ml-1) towards the mouse fibroblast 3T3 cells. In short the hexane fraction of Limnothrix sp. is a safe antioxidant additive for food and healthcare products. On the other hand, the hexane fraction of Leptolyngbya sp. is rich in alkaloids and was cytotoxic, with potential application in cancer therapy.

Environment friendly approach for size controllable synthesis of biocompatible Silver nanoparticles using diastase.

A green, facile method for the size selective synthesis of silver nanoparticles (AgNPs) using diastase as green reducing and stabilizing agent is reported. The thiol groups present in the diastase are mainly responsible for the rapid reaction rate of silver nanoparticles synthesis. The variation in the size and morphology of AgNPs were studied by changing the pH of diastase. The prepared silver nanoparticles were characterized by using UV-vis, XRD, FTIR, TEM and SAED. The FTIR analysis revealed the stabilization of diastase molecules on the surface of AgNPs. Additionally, in-vitro cytotoxicity experiments concluded that the cytotoxicity of the as-synthesized AgNPs towards mouse fibroblast (3T3) cell lines is dose and size dependent. Furthermore, the present method is an alternative to the traditional chemical methods of size controlled AgNPs synthesis.

Thymidine esters as substrate analogue inhibitors of angiogenic enzyme thymidine phosphorylase in vitro

Thymidine phosphorylase (TP) catalyzes the cleavage of thymidine into thymine and 2-deoxy-α-d-ribose-1-phosphate. Elevated activity of TP prevents apoptosis, and induces angiogenesis which ultimately leads to tumor growth and metastasis. Critical role of TP in cancer progression makes it a valid target in anti-cancer research. Discovery of small molecules as TP inhibitors is vigorously pursued in cancer therapy. In the present study, we functionalized thymidine as benzoyl ester to synthesize compounds 3–16. In vitro evaluation of thymidine esters for their thymidine phosphorylase inhibition activity was subsequently carried out. Compounds 4, 10, 14, and 15 showed good activities with lower IC50 values than the standard, 7-deazaxanthine (IC50=41.0±1.63μM). Among them, compound 14 showed five folds higher activity (IC50=7.5±0.8μM), while 4 (IC50=18.5±1.0μM) and 10 (IC50=18.8±1.2μM) showed two folds higher activity than the standard. Compound 15 showed slightly better activity (IC50=33.3±1.5μM) to the standard. Potent compounds were further subjected to kinetic and molecular docking studies to identify their mode of inhibition, and to study their interactions with the protein at atomic level, respectively. All active compounds were non-cytotoxic to mouse fibroblast 3T3 cell line. These results identify thymidine esters as substrate analogue (substrate-like) inhibitors of angiogenic enzyme thymidine phosphorylase for further studies.