Eradication of Helicobacter pylori through the inhibition of urease and peptide deformylase: Computational and biological studies.

This work tested anti- Helicobacter pylori, free radicals scavenging and toxicity property as well as chemical constituents in the extract of chloroform (CE) and ethyl acetate (EAE) from the pedicel of Diospyros kaki L. (PDK-CE and PDK-EAE). There were 33 and 36 chemical constituents respectively in the extracts of PDK-CE and PDK-EAE, belonging to the fatty acids methyl ester, fatty acids, and stearic acids, as revealed by Gas Chromatography-Mass Spectrometry (GC-MS). The extracts did not exhibit any toxicity on NIH3T3 cells, but they significantly showed scavenging of NO, DPPH, and H2O2 free radicals. The extracts displayed in vitro anti-H. pylori activity. PDK-CE had the maximum inhibitory zone at a minimal inhibitory concentration (MIC) of 10 µg. ml-1 and the extract also triggered the cellular damage in the bacteria. PDK-CE extract had a high urease inhibitory activity (IC50 value of 8.5 µg). Further, in silico studies was performed by using 41 compounds against H. pylori urease (HPU) and H. pylori peptide deformylase (HPPD). The score value was the maximum (-19.58 kcal/mol) against HPU with 17-(5-ethyl-6-methylheptan-2-yl)-10,13-dimethyl-2,3,4,7,8,9,11,12,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-3-ol, while the score value was the maximum (-14.51 kcal/mol) against HPPD with hexadecanoic acid. The results demonstrated the importance of the pedicel extracts in future pharmaceutical drug development against H. pylori infections.

Insulin-like Growth Factor 1 Analogs Clicked in the C Domain: Chemical Synthesis and Biological Activities.

Human insulin-like growth factor 1 (IGF-1) is a 70 amino acid protein hormone, with key impact on growth, development, and lifespan. The physiological and clinical importance of IGF-1 prompted challenging chemical and biological trials toward the development of its analogs as molecular tools for the IGF-1 receptor (IGF1-R) studies and as new therapeutics. Here, we report a new method for the total chemical synthesis of IGF-1 analogs, which entails the solid-phase synthesis of two IGF-1 precursor chains that is followed by the CuI-catalyzed azide-alkyne cycloaddition ligation and by biomimetic formation of a native pattern of disulfides. The connection of the two IGF-1 precursor chains by the triazole-containing moieties, and variation of its neighboring sequences (Arg36 and Arg37), was tolerated in IGF-1R binding and its activation. These new synthetic IGF-1 analogs are unique examples of disulfide bonds' rich proteins with intra main-chain triazole links. The methodology reported here also presents a convenient synthetic platform for the design and production of new analogs of this important human hormone with non-standard protein modifications.

In vitro antibacterial activity of poly (amidoamine)-G7 dendrimer.

BACKGROUND: Nano-scale dendrimers are synthetic macromolecules that frequently used in medical and health field. Traditional anibiotics are induce bacterial resistence so there is an urgent need for novel antibacterial drug invention. In the present study seventh generation poly (amidoamine) (PAMAM-G7) dendrimer was synthesized and its antibacterial activities were evaluated against representative Gram- negative and Gram-positive bacteria. METHODS: PAMAM-G7 was synthesized with divergent growth method. The structural and surface of PAMAM-G7 were investigated by transmission electron microscopy, scanning electron microscope and fourier transform infrared. Pseudomonas. aeruginosa (n = 15), E. coli (n = 15), Acinetobacter baumanni (n = 15), Shigella dysenteriae (n = 15), Klebsiella pneumoniae (n = 10), Proteus mirabilis (n = 15), Staphylococcus aureus (n = 15) and Bacillus subtilis (n = 10) have been used for antibacterial activity assay. Additionally, representative standard strains for each bacterium were included. Minimum Inhibitory Concentration (MIC) was determined using microdilution method. Subsequently, Minimum Bactericidal Concentration (MBC) was determined by sub-culturing each of the no growth wells onto Mueller Hinton agar medium. The cytotoxicity of PAMAM-G7 dendrimer were evaluated in HCT116 and NIH 3 T3 cells by MTT assay. RESULTS: The average size of each particle was approximately 20 nm. PAMAM-G7 was potentially to inhibit both Gram positive and gram negative growth. The MIC50 and MIC90 values were determined to be 2-4 µg/ml and 4-8 µg/ml, respectively. The MBC50 and MBC90 values were found to be 64-256 µg/ml and 128-256 µg/ml, respectively. The cytotoxity effect of dendrimer on HCT116 and NIH 3 T3 cells is dependent upon exposure time to and concentration of dendrimers. The most reduction (44.63 and 43%) in cell viability for HCT116 and NIH 3 T3 cells was observed at the highest concentration, 0.85 µM after 72 h treatmentm, respectively. CONCLUSIONS: This study we conclude that PAMAM-G7 dendrimer could be a potential candidate as a novel antibacterial agent.

Astragalosideâ £ against cardiac fibrosis by inhibiting TRPM7 channel.

BACKGROUND: Astragaloside Ⅳ (ASG-Ⅳ, (Fig. 1) is the most active component of Chinese sp. Astragalus membranaceus Bunge (Fabaceae) that has showed antioxidant, antiapoptotic and antiviral activities among others. It is reported to play an important role in cardiac fibrosis (CF), but the mechanism remains unclear. PURPOSE: To investigate the mechanism of ASG-Ⅳ on inhibiting myocardial fibrosis induced by hypoxia. STUDY DESIGN: We studied the relationship between anti-fibrotic effect of ASG-Ⅳ and transient receptor potential cation channel, subfamily M, member 7 (TRPM7) by in vivo and in vitro experiments. METHODS: In vivo, CF was induced by subcutaneous isoproterenol (ISO) for 10 days. Rat hearts were resected for histological experiment and reverse transcription real-time quantitative poly merase chain reaction (RT-qPCR). In vitro, molecular and cellular biology technologies were used to confirm the anti-fibrosis effect underlying mechanism of ASG-Ⅳ. RESULTS: Histological findings and the collagen volume fraction showed that ASG-Ⅳ decreased fibrosis in heart tissues. Hypoxia could stimulate the proliferation and differentiation of cardiac fibroblast which indicated that the degree of fibrosis was increased significantly. Anoxic treatment could also obviously up-regulate the expression of TRPM7 protein and current. ASG-Ⅳ groups showed the opposite results. Knock-down TRPM7 experiment further confirmed the role of TRPM7 channel in hypoxia-induced cardiac fibrosis. CONCLUSION: Our results suggest that the inhibition of hypoxia-induced CF in vivo and in vitro by ASG-IV is associated with reduction of the expression of TRPM7. The moderate inhibition of the TRPM7 channel may be a new strategy for treating cardiac fibrosis.

Evaluation of Qualea grandiflora Mart effect on HIF-1alpha and MMP-14 modulation in cell lines of pre-osteoblasts and fibroblasts / Avaliação do efeito da Qualea grandiflora Mart na modulação de HIF-1alpha e MMP-14 em linhagens celulares de fibroblastos e pré-osteoblastos

A espécie vegetal Qualea grandiflora (QG), popularmente conhecida como "pauferro", "pau-terra-da-folha-grande", "pau-terra" ou "pau-de-tucano", muito comum no Cerrado brasileiro, é bem conhecida devido às suas variadas propriedades terapêuticas. Suas indicações incluem ações preventivas no aparecimento de lesões de mucosa gástrica, efeitos analgésicos, antibacterianos, anti-inflamatórios e antifúngicos. Assim, os componentes da QG poderiam ter alguma ação sobre moléculas amplamente envolvidas em processos angiogênicos e de desenvolvimento/reparo, como a Metaloproteinase de matriz 14 (MMP-14) e o Fator Induzido por hipóxia 1α (HIF-1alfa). Dessa maneira, o objetivo deste estudo foi investigar os efeitos do extrato hidroalcoólico das folhas de QG na viabilidade celular e expressão de MMP-14 e HIF-1alpha em culturas de fibroblastos da linhagem NIH/3T3 e pré-osteoblastos da linhagem MC3T3-E1. Para o teste de viabilidade celular e expressão das moléculas, concentrações de 0.1; 1.0 e 10 µg/mL do extrato hidroalcoólico das folhas de QG foram administrados por períodos de 24, 48, 72 e 96h. Após cada período, a viabilidade celular foi avaliada pelo método de redução de MTT e a análise da expressão das moléculas foi feita por meio da técnica de imunofluorescência. Os resultados mostram que o extrato de QG não promove redução da viabilidade celular de fibroblastos e pré-osteoblastos em concentrações até 10 µg/mL, nos períodos iniciais (24 e 48h). Porém, uma redução significativa da viabilidade pode ser verificada nos períodos de 72h e 96h para os fibroblastos e 96h para os pré-osteoblastos, expostos a mais alta concentração do extrato (10 µg/mL). O ensaio de imunofluorescência indica que o extrato, nas concentrações de 0.1; 1.0 e 10 µg/mL foi capaz de aumentar a expressão de MMP-14 e HIF-1alpha, em ambos os tipos celulares. Em conclusão, nossos resultados indicam que o extrato de QG exerce um efeito capaz de aumentar a expressão das duas moléculas em estudo (MMP-14 e HIF-1alpha), tanto para os fibroblastos da linhagem NIH/3T3 como para os pré- osteoblastos da linhagem MC3T3-E1. Assim, os compostos de QG podem apresentar potencial para serem utilizados como agentes terapêuticos moduladores da angiogênese, por meio do aumento da expressão de MMP-14 e HIF-1alpha.(AU)

The vegetable specie Qualea grandiflora (QG), popularly known as "pau-ferro", "pauterra-da-folha-grande", "pau-terra" or "pau-de-tucano", very common in the Brazilian Cerrado, is well known due to its varied therapeutic properties. Its indications include preventive actions in the appearance of lesions of gastric mucosa, analgesic, antibacterial, anti-inflammatory and antifungal effects. Thus, QG components could have some action on molecules widely involved in angiogenic and developmental / repair processes, such as Matrix metalloproteinase 14 (MMP-14) and HypoxiaInducible Factor-1α (HIF-1alpha). Thus, the objective of our study was to investigate the effects of QG hydroalcoholic extract on cell viability and expression of MMP-14 and HIF-1alpha in NIH/3T3 fibroblasts and MC3T3-E1 pre-osteoblasts cell lines. For the cell viability assay and expression of the molecules, concentrations of 0.1; 1.0 and 10 µg / mL of the hydroalcoholic extract of leaves of QG, were administered for periods of 24, 48, 72 and 96h. After each period, the cell viability was evaluated by MTT assay and the expression of the molecules was analyzed using the immunofluorescence technique. The results show that the QG extract does not promote reduction of the cellular viability of fibroblasts and pre-osteoblasts in concentrations up to 10 µg/mL in the initial periods (24 and 48h). However, a significant reduction in viability can be observed in 72h and 96h for fibroblasts and 96h for pre-osteoblasts exposed to the highest extract concentration (10 µg/mL). The immunofluorescence assay indicates that the extract, at concentrations of 0.1; 1.0 and 10 µg/mL was able to increase the expression of MMP-14 and HIF-1alpha in both cell types. In conclusion, our results indicate that the QG extract exerts an effect capable of increasing the expression of the two molecules under study (MMP-14 and HIF-1alpha) both for the NIH/3T3 fibroblasts as well as for the MC3T3-E1 pre-osteoblasts cells. Thus, the QG compounds could have potential to be used as angiogenesis modulating therapeutic agents, by increasing the expression of MMP-14 and HIF-1alpha.(AU)

Adverse Phototoxic Effect of Essential Plant Oils on NIH 3T3 Cell Line after UV Light Exposure.

AIM: Natural or artificial substances have become an inseparable part of our lives. It is questionable whether adequate testing has been performed in order to ensure these substances do not pose a serious health risk. The principal aim of our research was to clarify the potential risk of adding essential oils to food, beverages and cosmetic products. METHODS: The toxicity of substances frequently employed in cosmetics, aromatherapy and food industry (bergamot oil, Litsea cubeba oil, orange oil, citral) were investigated using cell line NIH3T3 (mouse fibroblasts) with/without UV irradiation. The MTT assay was used to estimate the cell viability. Reactive oxygen species (ROS) which are products of a number of natural cellular processes such as oxygen metabolism and inflammation were measured to determine the extent of cellular stress. DNA damage caused by strand breaks was examined by comet assay. RESULTS: MTT test determined EC50 values for all tested substances, varying from 0.0023% v/v for bergamot oil to 0.018% v/v for citral. ROS production measurement showed that UV radiation induces oxidative stress to the cell resulting in higher ROS production compared to the control and non-irradiated samples. Comet assay revealed that both groups (UV, without UV) exert irreversible DNA damage resulting in a cell death. CONCLUSIONS: Our findings suggest that even low concentrations (lower than 0.0464% v/v) of orange oil can be considered as phototoxic (PIF value 8.2) and probably phototoxic for bergamot oil (PIF value 4.6). We also found significant changes in the cell viability, the ROS production and the DNA after the cells were exposed to the tested chemicals. Even though these substances are widely used as antioxidants it should be noted that they present a risk factor and their use in cosmetic and food products should be minimized.

Quercetin inhibits radiation-induced skin fibrosis.

Radiation induced fibrosis of the skin is a late toxicity that may result in loss of function due to reduced range of motion and pain. The current study sought to determine if oral delivery of quercetin mitigates radiation-induced cutaneous injury. Female C3H/HeN mice were fed control chow or quercetin-formulated chow (1% by weight). The right hind leg was exposed to 35 Gy of X rays and the mice were followed serially to assess acute toxicity and hind leg extension. Tissue samples were collected for assessment of soluble collagen and tissue cytokines. Human and murine fibroblasts were subjected to clonogenic assays to determine the effects of quercetin on radiation response. Contractility of fibroblasts was assessed with a collagen contraction assay in the presence or absence of quercetin and transforming growth factor-ß (TGF-ß). Western blotting of proteins involved in fibroblast contractility and TGF-ß signaling were performed. Quercetin treatment significantly reduced hind limb contracture, collagen accumulation and expression of TGF-ß in irradiated skin. Quercetin had no effect on the radioresponse of fibroblasts or murine tumors, but was capable of reducing the contractility of fibroblasts in response to TGF-ß, an effect that correlated with partial stabilization of phosphorylated cofilin. Quercetin is capable of mitigating radiation induced skin fibrosis and should be further explored as a therapy for radiation fibrosis.

Immunomodulatory properties of S- and N-alkylated 5-(1H-indol-2-yl)-1,3,4-oxadiazole-2(3H)-thione.

A series of S- and N-alkylated indolyloxadiazoles 2-7 were prepared. All compounds were tested for their immunomodulatory activity against T-cell proliferation, oxidative burst and cytokine analysis. Compounds 1, 2a, 2b, 2c and 2k demonstrated highly significant (P ≤ 0.005) inhibition on PHA activated T-cell proliferation with IC(50) less than 3 µg/mL concentration, while 3b exert a moderate inhibitory effect with IC(50) 8.6 µg/mL. Among all compounds of the series, only 2h was found to suppress phagocytes ROS production (IC(50) 2.4 µg/mL) in luminol-based chemiluminescence (CL) assay. Compounds 2a-k have stimulatory effect on proinflammatory cytokine predominantly IL-1ß but no effect on IL-4 and NO production indicating that these compounds might have selective inhibitory effect on T-cell proliferation. Cytotoxic effect on T-cell proliferation was tested on NIH-3T3 mouse fibroblast normal cell line. All compounds were found to be free from toxic effects up to 100 µM concentration.

Growth inhibition and induction of apoptosis in human cancerous HeLa cells by Maytenus procumbens.

The possible biochemical activities of the acetonic/ethanolic extract of the leaves of Maytenus procumbens (L.M.P), and its isolated compounds were investigated in the present study. In cytotoxicity assay, L.M.P showed IC(50) of 68.79, 51.22, 78.49, 76.59, and 76.64µg/ml on Caco-2, HeLa, HT29, NIH3T3, and T47D cells, respectively. Bioassay guided fractionation led to the isolation and identification of a new triterpene: '30-hydroxy-11α-methoxy-18ß-olean-12-en-3-one' (HMO) in addition to a known terpenoid: 'asiatic acid' (AA). HMO exhibited the most cytotoxicity against HeLa cells and was further investigated for its ability to induce apoptosis in HeLa cells. HMO induced apoptosis up to 20.41% in HeLa cells versus control group (0.40%). Antioxidant/oxidative properties of L.M.P and HMO were investigated using extracellular (DPPH), and intracellular (ROS) assays. Experimental samples represented a time and concentration-dependent formation of ROS in Hela cells. Generation of ROS seems one of the mechanisms by which HMO induces apoptosis in Hela cells. Conclusion is that the active components in L.M.P might serve as a mediator of the ROS scavenging system and have the potential to act as prooxidant or antioxidant depending on the biological environment of the cells.

Synthesis and biological evaluation of some thiazole derivatives as new cholinesterase inhibitors.

In the present study, some thiazole derivatives were synthesized via the ring closure reaction of 1-[2-(2-oxobenzo[d]thiazol-3(2H)-yl)acetyl]thiosemicarbazide with various phenacyl bromides. The chemical structures of the compounds were elucidated by (1)H NMR, (13)C NMR and mass spectral data and elemental analyses. Each derivative was evaluated for its ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) using a modification of Ellman's spectrophotometric method. The compounds were also investigated for their cytotoxic properties using MTT assay. The most potent AChE inhibitor was found as compound 4e (IC(50) = 25.5 ± 2.12 µg/mL) followed by compounds 4i (IC(50) = 38.50 ± 2.12 µg/mL), 4c (IC(50) = 58.42 ± 3.14 µg/mL) and 4g (IC(50) = 68 ± 2.12 µg/mL) when compared with eserine (IC(50) = 0.025 ± 0.01 µg/mL). Effective compounds on AChE exhibited weak inhibition on BuChE (IC(50) > 80 µg/mL). MTT assay indicated that the cytotoxic dose (IC(50) = 71.67 ± 7.63 µg/mL) of compound 4e was higher than its effective dose.

L-cysteine as a regulator for arsenic-mediated cancer-promoting and anti-cancer effects.

Previous studies have shown that activities of tyrosine kinases and secretion of the active form of matrix metalloproteinase-2 (MMP-2) are correlated with promotion of tumor growth, while apoptotic cell death in cancer cells is correlated with anti-cancer effects. Although arsenic has been reported to have both cancer-promoting and anti-cancer effects, the mechanisms of the arsenic-mediated bidirectional effects remain unknown. We examined the effects of arsenic on both proto-oncogene c-RET-transfected NIH3T3 cells with benign characters and oncogenic RET-MEN2A-transfected NIH3T3 cells with malignant characters. Arsenic promoted not only c-RET tyrosine kinase activity but also genetically activated RET-MEN2A kinase activity with promotion of dimer formation of RET proteins. Arsenic also increased secretion of the active form of MMP-2 in both RET-MEN2A-transfectants and c-RET-transfectants. On the other hand, arsenic promoted poly-(ADP-ribose) polymerase (PARP) degradation and cell death in both malignant and non-malignant cells. Interestingly, l-cysteine inhibited the arsenic-mediated tumor-promoting effects (activation of kinases and MMP-2 secretion) but not arsenic-mediated anti-cancer effects (PARP degradation and cell death). Our results suggest redox-linked regulation of arsenic-mediated activities of kinases and MMP-2 secretion but not arsenic-mediated cell death. Our results also suggest that l-cysteine is an ideal supplement that inhibits arsenic-mediated tumor-promoting effects without affecting arsenic-mediated anti-cancer effects.

Apoptosis and necrosis are involved in the toxicity of Sauropus androgynus in an in vitro study.

BACKGROUND/PURPOSE: The raw juice of the young sticks and leaves of Sauropus androgynus (SA) has been widely used as a natural food for body weight reduction and vision protection in Taiwan and Southeast Asia. But as has been reported, SA-associated obliterative bronchiolitis can develop after taking SA for more than 3 months. Lung transplantation was carried out in severe cases. METHODS: To study the toxic effect, we separated the SA extract into three parts, namely CHCl3, EtOAc and n-BuOH fractions, using polarity dissection. NIH3T3 fibroblasts were treated with the SA fractions 300 microg/mL and subjected to a series of cytotoxic assays. RESULTS: The EtOAc fraction exhibited the strongest effect of cell growth inhibition, followed by the CHCl3 and n-BuOH fractions. Features of condensed chromatin and apoptosis were observed in cells exposed to n-BuOH and EtOAc fractions using fluorescence microscopy. Formation of DNA ladders was also observed in the above cells. Instead, the CHCl3 fraction induced DNA smearing. In bivariate dot plots of annexin V and propidium iodide double staining, necrosis and apoptosis appeared in cells treated with CHCl3 and n-BuOH fractions, respectively, and a mixed type of necrosis and apoptosis appeared in EtOAc fraction-treated cells. CONCLUSION: Our results indicate that necrosis and apoptosis are involved in the toxic effect of SA in NIH3T3 fibroblasts. More evidence is needed to clarify if necrosis and apoptosis are also related to the pathogenesis of SA-associated obliterative bronchiolitis.

Tissue anti-adhesion potential of ibuprofen-loaded PLLA-PEG diblock copolymer films.

This study was designed to evaluate the effect of polyethylene glycol (PEG) and nonsteroidal anti-inflammatory drug (ibuprofen) on the prevention of postsurgical tissue adhesion. For this, poly(L-lactic acid) (PLLA)-PEG diblock copolymers were synthesized by ring opening polymerization of L-lactide and methoxy polyethylene glycol (Mw 5000) of different compositions. The synthesized copolymers were characterized by gel permeation chromatography and 1H-nuclear magnetic resonance spectroscopy. PLLA-PEG copolymer films were prepared by solvent casting. The prepared copolymer films were more flexible and hydrophilic than the control PLLA film, as investigated by the measurements of glass transition temperature, water absorption content, and water contact angle. The drug release behavior from the ibuprofen (10 wt%)-loaded copolymer films was examined by high performance liquid chromatography. It was observed that the drug was released gradually up to about 40% of total loading amount after 20 days, depending on PEG composition; more drug release from the films with higher PEG compositions. In vitro cell adhesions on the copolymer films with/without drug were compared by the culture of NIH/3T3 mouse embryo fibroblasts on the surfaces. For in vivo evaluation of tissue anti-adhesion potential, the copolymer films with/without drug were implanted between the cecum and peritoneal wall defects of rats and their tissue adhesion extents were compared. It was observed that the ibuprofen-containing PLLA-PEG films with high PEG composition (particularly PLLA113-PEG113 film with PEG composition, 50 mol%) were very effective in preventing cell or tissue adhesion on the film surfaces, probably owing to the synergistic effects of highly mobile, hydrophilic PEG and anti-inflammatory drug, ibuprofen.