Elisa Ovidi

Identification and Characterization of a Novel Microtubule-Based Motor Associated with Membranous Organelles in Tobacco Pollen Tubes

Pollen tube growth depends on the differential distribution of organelles and vesicles along the tube. The role of microtubules in organelle movement is uncertain, mainly because information at the molecular level is limited. In an effort to understand the molecular basis of microtubule-based movement, we isolated from tobacco pollen tubes polypeptides that cosediment with microtubules in an ATP-dependent manner. Major polypeptides released from microtubules by ATP (ATP-MAPs) had molecular masses of 90, 80, and 41 kD. Several findings indicate that the 90-kD ATP-MAP is a kinesin-related motor: binding of the polypeptide to microtubules was enhanced by the nonhydrolyzable ATP analog AMP-PNP; the 90-kD polypeptide reacted specifically with a peptide antibody directed against a highly conserved region in the motor domain of the kinesin superfamily; purified 90-kD ATP-MAP induced microtubules to glide in motility assays in vitro; and the 90-kD ATP-MAP cofractionated with microtubule-activated ATPase activity. Immunolocalization studies indicated that the 90-kD ATP-MAP binds to organelles associated with microtubules in the cortical region of the pollen tube. These findings suggest that the 90-kD ATP-MAP is a kinesin-related microtubule motor that moves organelles in the cortex of growing pollen tubes.

Natural products for human health: an historical overview of the drug discovery approaches

Abstract Natural products (NPs) are secondary metabolites produced and used by organisms for defending or adapting purposes. These molecules were naturally selected during thousands of years to improve the specificity and cover a very wide range of functions, depending on the origin, the habitat and the specific activity carried out in the organism of origin. Due to these intrinsic features, NPs have been used as healing agents since thousands of years and still today continue to be the most important source of new potential therapeutic preparations.The purpose of this review is to provide information about the historical evolution of the NPs investigation methods, focusing attention on the relative benefit/problems emerged after the improvement of the scientific investigations about them, especially over the last two centuries. Taken together, the reported information lead to the central role of NPs in the future of drug development for human needs.

Aromatic Medicinal Plants of the Lamiaceae Family from Uzbekistan: Ethnopharmacology, Essential Oils Composition, and Biological Activities

Plants of the Lamiaceae family are important ornamental, medicinal, and aromatic plants, many of which produce essential oils that are used in traditional and modern medicine, and in the food, cosmetics, and pharmaceutical industry. Various species of the genera Hyssopus, Leonurus, Mentha, Nepeta, Origanum, Perovskia, Phlomis, Salvia, Scutellaria, and Ziziphora are widespread throughout the world, are the most popular plants in Uzbek traditional remedies, and are often used for the treatment of wounds, gastritis, infections, dermatitis, bronchitis, and inflammation. Extensive studies of the chemical components of these plants have led to the identification of many compounds, as well as essentials oils, with medicinal and other commercial values. The purpose of this review is to provide a critical overview of the literature surrounding the traditional uses, ethnopharmacology, biological activities, and essential oils composition of aromatic plants of the family Lamiaceae, from the Uzbek flora.

Antiproliferative activity of yatein isolated from Austrocedrus chilensis against murine myeloma cells: Cytological studies and chemical investigations

Abstract Context: Fitzroya cupressoides (Molina) I. M. Johnst. and Austrocedrus chilensis (D. Don) Pic.Serm. & Bizzarri are two Chilean Cupressaceae that are naturally resistant to biodegradation. Secondary metabolites from these species display a variety of biological activities. Objective: To evaluate the antiproliferative activity of two lignans, a diterpene and a flavonol isolated from A. chilensis and F. cupressoides, to elucidate their cytological effects on P3X murine myeloma cells. Materials and methods: The antiproliferative activity of yatein, isotaxiresinol, ferruginol, and isorhamnetin was evaluated in vitro using the MTT assay. The effect of yatein at the cellular level, due to its high antiproliferative activity was evaluated. P3X cells treated for 24 h with 12.5 and 25 µg/mL of yatein were also examined at the cytological level using immunofluorescence and scanning and transmission electron microscopy. Results: Yatein, a lignan isolated from A. chilensis, potentially inhibited P3X murine myeloma cell proliferation, resulting in approximately 75% cell death in response to a 25 µg/mL treatment with the lignan. P3X cells lost membrane integrity at the nuclear and cytoplasmic levels, including organelles, in response to yatein treatment (12.5 µg/mL), and we observed changes in the cytoplasmic organization and distribution of microtubules. The other compounds tested had low activity. Discussion and conclusions: Yatein is a lignan precursor of podophyllotoxin, a key agent in anticancer drugs. Due to its structural similarities to podophyllotoxin, yatein could have similar cytoplasmic target(s), such as the microtubular apparatus. These findings suggest that yatein may be of potential pharmacological interest and warrants further investigation in human cell lines.

Identification and isolation of non-polar compounds from the chloroform extract of Scutellaria ramosissima

In the present study, chloroform extract obtained from aerial parts of Scutellaria ramosissima was phytochemically investigated. A non-polar fraction was obtained from the chloroform extract and the chemical composition of this fraction was identified by GC–MS. The major components of the non-polar fraction of S. ramosissima were determined as heneicosane (12.18%), palmitic acid (11.79%), acetovanillone (6.28%), 5,6-dihydroxy-7,8-dimethoxyflavone (31.87%), (9Z)-octadecenoic (oleic) acid (8.21%), stigmasterol (2.68%), β-sitosterol (2.65%) and 5,2′-dihydroxy-6,7,8,6′-tetramethoxyflavone (2.13%). In addition, 5,6-dihydroxy-7,8-dimethoxyflavone was isolated from the same fraction by PTLC.

Chemical investigations of male and female leaf extracts from Schinus molle L.

Abstract The pepper-tree Schinus molle is an evergreen ornamental plant with various and diversified list of medical uses. In this article we analysed the chemical composition of male and female leaves of this plant during the off-flowering and flowering seasons. The leaf extracts were obtained by using a sequential extraction with solvents of different polarities and the chemical composition was investigated by GC-MS. The results showed a total of twenty-three components, in which elemol is the most abundant constituent followed by bicyclogermacrene, γ-eudesmol, α-eudesmol, β-eudesmol and isocalamendiol. The petroleum ether and diethyl ether extracts from male and female flowering and off-flowering leaves consisted of sesquiterpene hydrocarbons as a major constituent followed by monoterpene hydrocarbons, while the acetone extracts showed a different composition. The obtained results show differences in the chemical composition between male and female and flowering and not flowering.

Phytochemical and Pharmacological Properties of Medicinal Plants from Uzbekistan: A Review

Medicinal plants are a reservoir of biologically active compounds with therapeutic properties that over time have been discovered and used by diverse groups of people for treatment of various ailments. In this regard, Uzbekistan has an excellent historic research base of herbal medicines with about 70% of Uzbek households using medicinal plants to meet their health needs for several centuries. The flora of Uzbekistan includes more than 4500 species of vascular plants and over 600 of these plants are used in traditional or conventional medicines, significantly surpassing other areas by the absolute number of endemics and the percentage of endemism. The plants are a reservoir of secondary metabolites, suitable for use in pharmacological studies with a high possibility of observing biologically active constituents. The present review provides an up-todate a report on the phytochemicals and pharmacological activity of the medicinal plants widely used in Uzbekistan. As a country, Uzbekistan appears to be a source of novel herbal drugs that have not yet been fully evaluated. We trust the present report will be useful for further investigations on the medicinal activity of indigenous plant species in