Anti-Proliferative Activity of A Hydrophilic Extract of Manna from Fraxinus angustifolia Vahl through Mitochondrial Pathway-Mediated Apoptosis and Cell Cycle Arrest in Human Colon Cancer Cells.

Manna is produced from the spontaneous solidification of the sap of some Fraxinus species, and, owing its content in mannitol, is used in medicine as a mild laxative. Manna is also a rich source of characteristic bio-phenols with reducing, antioxidant and anti-inflammatory properties. This study assesses the activity of a hydrophilic extract of manna (HME) on cellular and molecular events in human colon-rectal cancer cells. HME showed a time- and concentration-dependent anti-proliferative activity, measured by MTT assay, in all the cell lines examined, namely Caco-2, HCT-116 and HT-29. The amounts of HME that caused 50% of cell death after a 24 h treatment were 8.51 ± 0.77, 10.73 ± 1.22 and 28.92 ± 1.99 mg manna equivalents/mL, respectively; no toxicity was observed in normally differentiated Caco-2 intestinal cells. Hydroxytyrosol, a component of HME known for its cytotoxic effects on colon cancer cells, was ineffective, at least at the concentration occurring in the extract. Through flow-cytometric techniques and Western blot analysis, we show that HME treatment causes apoptosis, assessed by phosphatidylserine exposure, as well as a loss of mitochondrial membrane potential, an intracellular formation of reactive oxygen species (ROS), increases in the levels of cleaved PARP-1, caspase 3 and Bax, and a decrease in Bcl-2 expression. Moreover, HME interferes with cell cycle progression, with a block at the G1/S transition. In conclusion, the phytocomplex extracted from manna exerts an anti-proliferative activity on human colon cancer cells through the activation of mitochondrial pathway-mediated apoptosis and cell cycle arrest. Our data may suggest that manna could have the potential to exert chemo-preventive effects for the intestine.

Neuroprotective effects of Fraxinus angustifolia Vahl. bark extract against Alzheimer's disease.

Alzheimer disease's (AD) is a neurodegenerative disease induced by amyloid-ß (Aß) aggregation and accumulation of neurotoxic metals in the brain. Fraxinus angustifolia Vahl. (Oleaceae) is a Mediterranean plant traditionally used to treat several human problems as nervous system problems. This study aimed to evaluate the neuroprotective effects of F. angustifolia Vahl. bark extract (FAB) in vitro and in vivo against Aß-aggregation and aluminium induced-neurotoxicity in mice. FAB was characterized by colorimetric methods and its individual compounds were identified and quantified by LC-MS. First, the neuroprotective effect of FAB was evaluated against Aß25-35-aggregation where it was directly incubated with Aß25-35 and the kinetic of aggregation was measured by spectrophotometer at 200 nm. Then, the extract was tested against Aß25-35-induced cytotoxicity on PC12 cells and the cells viability was determined by MTT test. On the other hand, FAB (0.01-0.5 mg/mL) was tested against aluminium-activated lipid peroxidation in mice synaptosomal membranes, and in vivo against aluminium-caused neurotoxicity in male N.M.R.I. (Naval Medical Research Institute) mice; this test consisted of daily co-administration of the extract with Al for 60 days. At the end of the treatment, behavioral and memory tests (locomotor activity, black and white and Morris water maze tests) and histological analysis were realized. The identification and quantification of FAB phenolics revealed the presence of different phenolic classes with high concentration of phenylethanoids and hydroxycoumarins. FAB showed a high Aß25-35 anti-aggregative effect and a dose dependent protective effect on PC12 cells. The extract also demonstrated a significant inhibition of lipid peroxidation and was found to prevent the Al harmful effects where it significantly increased the locomotor activity, decreased the anxiety, improved memory and reduced histological alterations. In conclusion, FAB is rich of bioactive compounds that gave it the ability to inhibit Aß-aggregation and Al-caused neurotoxicity in mice.

Identification of bioactive compounds from Fraxinus angustifolia extracts with anti- NADH oxidase activity of bovine milk xanthine oxidoreductase.

Fraxinus angustifolia leaves and bark are used in traditional medicine against various inflammatory-related pathologies incumbent to reactive oxygen species (ROS) generation by the NADH oxidase activity of enzymes such as xanthine oxidoreductase (XOR). This study was designed to investigate the in vitro and in vivo inhibitory activities of this enzyme by Fraxinus angustifolia extracts. The leaf organic phase of ethyl acetate (LFA) and its bark aqueous counterpart (BFA) showed the strongest anti-NADH oxidase activity in vitro (IC50 = 38.51 and 42.04 µg mL-1, respectively). They consequently suppressed superoxide generation both enzymatically (53% and 19%, respectively) and nonenzymatically (34% and 19%, respectively). These results were corroborated in vivo, with high antiNADH oxidase potential of the leaves and bark extracts (75.32% and 51.32%, respectively) concomitant with moderate hypouricemic activities (36.84% and 38.59%, respectively). Bio-guided fractionation led to the identification, by LC-DAD-MS/MS, of esculin and calcelarioside in bark and kaempferol glucoside in leaves as the main compounds responsible for the anti-NADH oxidase activity of XOR. These results plead in favor of the use of F. angustifolia as a source of potentially interesting therapeutic substances.

Fixed oil from seeds of narrow-leaved ash (F. angustifolia subsp. angustifolia): Chemical profile, antioxidant and antiproliferative activities.

Fraxinus angustifolia subsp. angustifolia is a plant with an age-old use for the production of manna. However, it is also a valuable source of fixed oil rich-seeds. In the present study we examined the chemical and biological properties of this oil in order to support a possible application in foodstuffs, nutraceuticals and cosmetics. Fatty acid composition, volatile and phenolic substances were evaluated. Oleic and linoleic acid represented 45.5% and 50.0%, respectively, of the total fatty acid composition. Among polar phenolic substances identified (secoiridoids, phenylethanoid glycosides, phenolic acids and alcohols, flavonoids, coumarins) isoverbascoside is for the first time reported in this species. Volatiles were mainly characterized by sesquiterpenes. The oil showed good antioxidant activity, in terms of ABTS radical scavenging activity, with an IC50 value of 28.2 µg/mL. The antiproliferative activity was also investigated: amelanotic melanoma (C32) and lung carcinoma (A549) cells were the most sensitive with IC50 values comparable to that of the positive control vinblastine. These findings shed light on the potential use of F. angustifolia subsp. angustifolia fixed oil in nutraceutics and cosmetics.

Experimental arid land afforestation in Central Anatolia, Turkey.

The afforestation of arid lands faces many challenges, and perhaps the most important key for success is choosing one or more species that are adapted well for local environmental conditions. We explored species that would be suitable for the steppe region of Central Anatolia. Intensive site preparation included ripping the subsoil (to 80 cm) and plowing the upper soil before planting seedlings of Elaeagnus angustifolia, Robinia pseudoacacia, Fraxinus angustifolia, and Pinus nigra were used as tree species. We also tested the success of several shrub species: Amygdalus orientalis, Calligonum polygonoides, and Spartium junceum. After five growing seasons, E. angustifolia showed the highest survival, with 80% of planted seedlings remaining. For the shrubs, A. orientalis was the most successful species with a 95% survival rate. Broad-leaved trees grew a cumulative average of 34 cm in height in 5 years, whereas P. nigra seedings grew only 9 cm. The greatest height growth occurred in the shrubs, with A. orientalis gaining 40 cm in height in 5 years. Overall, E. angustifolia and A. orientalis appeared best suited for afforestation in these areas. R. pseodoacacia and F. angustifolia may also be used as alternative species.

Hepatoprotective and antidiabetic activities of Fraxinus angustifolia Vahl extracts in animal models: characterization by high performance liquid chromatography analysis.

BACKGROUND/AIM: The present study was designed to explore antidiabetic and hepatoprotective potentials of Fraxinus angustifolia leaf (FAL) and bark (FAB) extracts in vivo. MATERIALS AND METHODS: Streptozotocin (STZ)-induced diabetic rats, pretreated with the extracts (25 and 50 mg/kg), were monitored for fasting blood glucose (FBG) levels. Hepatoprotective potential was examined after injection of an excessive dose of paracetamol (10 g/60 kg) by analysis of biochemical parameters (transaminases, bilirubin), malondialdehyde (MDA) levels, and histological sections. high performance liquid chromatography analysis was also performed for partial characterization. RESULTS: A considerable hypoglycemic effect was noticed 2 h after the STZ-induction, with a higher efficiency (P < 0.05) for FAL (68%) as compared with FAB (57%). A significant (P < 0.05) reduction in MDA was observed for paracetamol-fed mice pretreated with FAL (50 mg/kg), FAB (50 mg/kg), or both (25 mg/kg each) extracts, and the MDA levels for the three conditions were 0.290 ± 0.034, 0.340 ± 0.038, and 0.25 ± 0.058 nmoles/mg of liver tissue, respectively). Hence, simultaneous treatment provided a better protection. Histological observations confirmed the higher hepatoprotective potential of FAL over FAB extracts. CONCLUSION: The obtained results indicate the possibility of pharmacological exploitation of F. angustifolia extracts in the treatment of diabetes and associated liver diseases.