Roula M. Abdel-Massih

The apoptotic and anti-proliferative activity of 'Origanum majorana' extracts on human leukemic cell line

Scientists are constantly searching for phytochemicals and compounds with anti-cancer and antioxidant activity. In this study, the anti-proliferative activity of plant extracts from Origanum majorana (marjoram) was tested on human lymphoblastic leukemia cell line Jurkat. Cytotoxicity was examined using non-radioactive cytotoxicity assay and the IC(50) was calculated. At non-cytotoxic concentrations, the viability of cells decreased with increase of concentration of plant extract. The anti-proliferative effect was also found to be dose-dependent. Analysis via flow cytometry shows that marjoram extracts stimulated apoptosis. Induction of apoptosis was caused by an up-regulation of p53 protein levels and down-regulation of Bcl-2alpha. Marjoram exhibited a strong scavenging activity (SC(50)=0.03mg dry weight). The conclusions from this study suggest that marjoram extracts exhibit anti-proliferative effect and high antioxidant activity. For that it merits further investigation as a potential therapeutic agent.

Antibacterial Activity of the Extracts Obtained from Rosmarinus officinalis, Origanum majorana, and Trigonella foenum-graecum on Highly Drug-Resistant Gram Negative Bacilli

Our aim was to determine the antimicrobial activity of three selected plants ( Rosmarinus officinalis, Origanum majorana, and Trigonella foenum-graecum) against Extended Spectrum Beta Lactamase (ESBL)—producing Escherichia coli and Klebsiella pneumoniae— and to identify the specific plant fraction responsible for the antimicrobial activity. The plants were extracted with ethanol to yield the crude extract which was further subfractionated by different solvents to obtain the petroleum ether, the dichloromethane, the ethyl acetate, and the aqueous fractions. The Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC) were determined using broth microdilution. The MICs ranged between 1.25 and 80  𝜇 g / 𝜇 l . The majority of these microorganisms were inhibited by 80 and 40  𝜇 g / 𝜇 l of the crude extracts. The petroleum ether fraction of Origanum majorana significantly inhibited 94% of the tested strains. Ethyl acetate extracts of all selected plants exhibited relatively low MICs and could be therefore described as strong antibacterial.

Microbial transformation of nandrolone with Cunninghamella echinulata and Cunninghamella blakesleeana and evaluation of leishmaniacidal activity of transformed products

Therapeutic potential of nandrolone and its derivatives against leishmaniasis has been studied. A number of derivatives of nandrolone (1) were synthesized through biotransformation. Microbial transformation of nandrolone (1) with Cunninghamella echinulata and Cunninghamella blakesleeana yielded three new metabolites, 10β,12β,17β-trihydroxy-19-nor-4-androsten-3-one (2), 10β,16α,17β-trihydroxy-19-nor-4-androsten-3-one (3), and 6β,10β,17β-trihydroxy-19-nor-4-androsten-3-one (4), along with four known metabolites, 10β,17β-dihydroxy-19-nor-4-androsten-3-one (5), 6β,17β-dihydroxy-19-nor-4-androsten-3-one (6) 10β-hydroxy-19-nor-4-androsten-3,17-dione (7) and 16β,17β-dihydroxy-19-nor-4-androsten-3-one (8). Compounds 1-8 were evaluated for their anti-leishmanial activity. Compounds 1 and 8 showed a significant activity in vitro against Leishmania major. The leishmanicidal potential of compounds 1-8 (IC50=32.0±0.5, >100, 77.39±5.52, 70.90±1.16, 54.94±1.01, 80.23±3.39, 61.12±1.39 and 29.55±1.14 μM, respectively) can form the basis for the development of effective therapies against the protozoal tropical disease leishmaniasis.

Galactosyl- and fucosyltransferases in etiolated pea epicotyls : product identification and sub-cellular localisation

Summary Particulate membrane preparations from etiolated pea epicotyls were found to contain fucosyltransferases, which transferred fucose from GDP-fucose onto xyloglucan and N-linked glycoprotein, and galactosyltransferases, which transferred galactose from UDP-galactose onto galactan, xyloglucan, and N-linked glycoprotein. The products were characterised by specific enzyme degradation and by acid and alkaline hydrolysis. All the enzymes were found to be concentrated in the Golgi apparatus. The Golgi apparatus was further fractionated into membranes of low, medium and high-density. The glycoprotein fucosyltransferase activity was present in highest amounts in the medium-density Golgi membranes, while the majority of the xyloglucan fucosyltransferase was present in the low-density Golgi membranes. The majority of the galactan galactosyltransferase (galactan synthase) was found in the low-density membranes, while the glycoprotein galactosyltransferase was equally distributed in all three subfractions.

Protein- and pH-dependent binding of nascent pectin and glucuronoarabinoxylan to xyloglucan in pea

Abstract. Nascent pectin and glucuronoarabinoxylan, synthesised in vitro by membrane-bound enzymes from etiolated pea (Pisum sativum L.) epicotyls, were found to bind to pea xyloglucan in a pH-dependent manner. The binding was maximum at low pH (3–4), and decreased to almost zero at pH 6. The binding was probably non-covalent and reached saturation within 5 min. Removal of the fucose residues of xyloglucan decreased the degree of binding. Removal by protease of the proteins attached to nascent pectin and glucuronoarabinoxylan greatly reduced the maximum binding and abolished the pH-dependence. The observed binding may be of considerable significance in the process of cell-wall assembly and in the control of cell extension.

The effect of PEG-coated gold nanoparticles on the anti-proliferative potential of Specific Nutrient Synergy

Abstract The role of PEG-coated gold nanoparticles (Au NPs) on the anti-proliferative effect of Specific Nutrient Synergy (SNS) on HTLV-1 infected (C91-PL and HuT-102) and non-infected (CEM and Jurkat) malignant T-lymphocytes cells, was investigated. When PEG-coated Au NPs (of different molecular weights) were added alone, there was no effect on either viability or proliferation of the leukemic cell lines studied. Treatment of cells with SNS and PEG (5 or 10 kDa) coated Au NP reduced significantly the proliferation in all cell lines tested; this reached more than 50% reduction as compared to the control for cells treated for 96 h. Data showed that the best anti-proliferative effect was obtained using SNS and Au NP coated with PEG of molecular weights of 5 and 10 kDa with almost no effect of PEG of lower molecular weights (0.75 and 2 kDa) or higher ones (20 kDa). This was true as well for HTLV-1 infected as for non-infected malignant T-lymphocytes. Electron microscopy results showed uptake of the gold particles to Jurkat cells. All described effects are specific to leukemia cell lines, and no effects were observed with freshly activated human mononuclear lymphocytes as control.

Detection of genotoxicity in hospital wastewater of a developing country using SOS chromotest and Ames fluctuation test

Background: Hospitals discharge considerable amounts of chemicals in their wastewaters that may be genotoxic or present serious health hazards. The genotoxic potential of wastewater in a Lebanese University Hospital was evaluated using the SOS Chromotest and the Ames fluctuation test. Different concentrations were tested to determine the recommended dilution for each sample to decrease its genotoxicity. Methods: The samples were taken from 5 different pits, 2 times per day in the morning and in the afternoon during two 1-week (5 days) periods in February and August 2011. SOS Chromotest and the Ames fluctuation were used to test genotoxicity. Results and conclusions: This study revealed that hospital wastewater was mostly genotoxic. 50% of the samples were positive for genotoxicity in the SOS Chromotest and 67.5% in the Ames fluctuation test. Genotoxicity of the sample was affected by the time, day, and season of sample collection. Different pits, representing different wastewater collection points, also varied with respect to the intensity of genotoxicity. Other genotoxic tests are currently underway to further evaluate the toxicity of these samples and to identify the genotoxic com pounds. This study shows that hospital wastewater must be carefully monitored and proper disposal or treatment measures need to be implemented.

Physicochemical characteristics, mutagenicity and genotoxicity of airborne particles under industrial and rural influences in Northern Lebanon

In this work, the main objectives were to assess the mutagenic and genotoxic effects of fine particulate matter collected in an industrial influenced site in comparison with a non-industrial influenced one (rural site) and to relate the particulate matter (PM) composition to the observed genotoxic effects. At the industrial influenced site, higher concentrations of phosphates, trace metals, and polycyclic aromatic hydrocarbons (PAHs) in particles could be related to the contributions of quarries, fertilizer producer, cement plants, and tires burning. Gasoline and diesel combustion contributions were evidenced in particles collected at both sites. Particles collected under industrial influence showed a higher mutagenic potential on three tested strains of Salmonella typhimurium (TA98, YG1041, and TA102), and especially on the YG1041, compared to particles from the rural site. Furthermore, only particles collected in the vicinity of the industrial site showed a tendency to activate the SOS responses in Escherichia coli PQ37, which is indicative of DNA damage as a result of exposure of the bacteria cells to the action of mutagenic samples. The mutagenicity and genotoxicity of the industrial PM2.5–0.3 particulates may be attributed to its composition especially in organic compounds. This study showed that proximity of industries can affect local PM composition as well as PM genotoxic and mutagenic potential.

Microbial transformation of contraceptive drug etonogestrel into new metabolites with Cunninghamella blakesleeana and Cunninghamella echinulata.

Biotransformation of a steroidal contraceptive drug, etonogestrel (1), (13-ethyl-17β-hydroxy-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-3-one) was investigated with Cunninghamella blakesleeana and C. echinulata. Five metabolites 2-6 were obtained on incubation of 1 with Cunninghamella blakesleeana, and three metabolites, 2, 4, and 6 were isolated from the transformation of 1 with C. echinulata. Among them, metabolites 2-4 were identified as new compounds. Their structures were deduced as 6β-hydroxy-11,22-epoxy-etonogestrel (2), 11,22-epoxy-etonogestrel (3), 10β-hydroxy-etonogestrel (4), 6β-hydroxy-etonogestrel (5), and 14α-hydroxy-etonogestrel (6). Compounds 1-6 were evaluated for various biological activities. Interestingly, compound 5 was found to be active against β-glucuronidase enzyme with IC50 value of 13.97±0.12μM, in comparison to standard compound, d-saccharic acid 1,4-lactone (IC50=45.75±2.16μM). Intestinal bacteria produce β-glucuronidase. Increased activity of β-glucuronidase is responsible for the hydrolyses of glucuronic acid conjugates of estrogen and other toxic substances in the colon, which plays a key role in the etiology of colon cancer. Inhibition of β-glucoronidase enzyme therefore has a therapeutic significance. Compounds 1-6 were also found to be non cytotoxic against 3T3 mouse fibroblast cell lines.

Immunomodulatory effect of natural and modified Citrus pectin on cytokine levels in the spleen of BALB/c mice

Pectin is present in the cell wall of different vegetables and fruits. Beside its importance in the plant cell wall, pectin has enticed great attention for its beneficial effects on human health. It was shown to decrease cholesterol levels, to possess anti-oxidative, anti-bacterial and anti-cancer activity. The immunomodulatory activity of pectin and its mechanism of action is recently being investigated. In this study, the differential immunomodulatory activities of both CP (citrus pectin) and MCP (modified citrus pectin) were investigated. Females BALB/c mice (20-25 g) were randomly divided into 7 groups and different concentrations of CP and MCP (0%, 1.5%, 3% and 5%) were added to their drinking water for 21 days. Then, the splenic level of IL-1β, IL-4, IL-10, IL-17, IFN-γ and TNF-α were evaluated using ELISA. Both CP and MCP exhibited immunomodulatory activities by increasing the levels of the pro-inflammatory cytokines IL-17, IFN-γ and TNF-α levels. This tendency seems to be regulated by the up-regulation of IL-4 levels but with no major effect on those of IL-10. Therefore, CP and especially MCP have potential immunomodulatory effects which might be highly beneficial in immunotherapy.Pectin is present in the cell wall of different vegetables and fruits. Beside its importance in the plant cell wall, pectin has enticed great attention for its beneficial effects on human health. It was shown to decrease cholesterol levels, to possess anti-oxidative, anti-bacterial and anti-cancer activity. The immunomodulatory activity of pectin and its mechanism of action is recently being investigated. In this study, the differential immunomodulatory activities of both CP (citrus pectin) and MCP (modified citrus pectin) were investigated. Females BALB/c mice (20-25 g) were randomly divided into 7 groups and different concentrations of CP and MCP (0%, 1.5%, 3% and 5%) were added to their drinking water for 21 days. Then, the splenic level of IL-1β, IL-4, IL-10, IL-17, IFN-γ and TNF-α were evaluated using ELISA. Both CP and MCP exhibited immunomodulatory activities by increasing the levels of the pro-inflammatory cytokines IL-17, IFN-γ and TNF-α levels. This tendency seems to be regulated by the up-regulation of IL-4 levels but with no major effect on those of IL-10. Therefore, CP and especially MCP have potential immunomodulatory effects which might be highly beneficial in immunotherapy.