109 research outputs found
SYNTHESIS OF WATER-SOLUBLE, POLYESTER-BASED DENDRIMER PRODRUGS FOR EXPLOITING THERAPEUTIC PROPERTIES OF TWO TRITERPENOID ACIDS
Dendrimers are macromolecules characterized by high controlled size, shape and architecture, presence of inner cavities able to accommodate small molecules and many peripheral functional groups to bind target entities and are of eminent interest for biomedical applications, including gene transfection, tissue engineering, imaging, drug delivery. The well-known pharmacological activities of Ursolic and Oleanolic acids are limited by their small water solubility, non-specific cells distribution, low bioavailability, poor pharmacokinetics and their direct administration could result in the release of thrombi. To overcome such problems, in this paper we described their physical incorporation inside amino acids-modified polyester-based dendrimers which made them highly water-soluble. IR, NMR, zeta potential, mean size of particles, buffer capacity and drugs release profiles of prepared materials were reported. The achieved water-soluble complexes harmonize a polycationic character and a buffer capacity which presuppose efficient cells penetration and increased residence time with a biodegradable cells respectful scaffold thus appearing a promising team of not toxic prodrugs for safe administration of Ursolic and Oleanolic acids
From the experience of \u201cPLANT\u201d and \u201cPYRGY\u201d EU Projects onwards: interdisciplinary link of medicinal plant science with history and art
The iconography of medicinal and aromatic plant in art masterpieces can be an interesting contribution to the ethnobotanical knowledge related to the historic period when the artefact was produced. Along herbarium specimens, sometimes misrepresenting the morphological characters, the images inside artistic expressions not meant for scientific purposes, and often related to complex symbolic meanings, are of interest also from the botanical and the pharmaceutical point of view. Within the work of the EU project \u201cPlants in European Masterpieces (PLANT)\u201d we considered 100 species of ethnobotanical interest into 25 paintings and frescoes of XVI century in the Genoese museums or in other museums but having Genoa as a subject. Part of the dissemination activities of the EU project \u201cStrategia d\u2019impresa in settori di nicchia per l\u2019economia agroindustriale del Mediterraneo (PYRGI)\u201dwere devoted to the comparative study of a Genoese collection of pharmacy jars, pharmacy recipes of pharmacopoeias used in the past in Liguria, and aromatic and medicinal plants of the Ligurian area. For both projects a relational database ad hoc developed, having specific tables for all the three main sections of study (art, botany and pharmaceutical and ethnobotanical knowledge), was produced. These databases were the backbones of the PLANT desktop application and of the web site for PYRGI respectively. The hyperlink trees allow the user to navigate among reconstructions of ancient recipes, the botanical information and the related masterpiece. The ongoing research is focused on other paintings of the Genoese collections of the Musei di Strada Nuova. The painting I santi Sebastiano, Giovanni Battista e Francesco; Madonna con il Bambino e Angeli (1502-1503) by Filippino Lippi, is of particular relevance, with 43 entities; 36 of which are herbaceous species. 18 taxa are clearly identifiable, belonging to Pteridophtyes (2 taxa) and Angiosperm Dicotyledons (16 taxa)
Autoxidation Products of the Methanolic Extract of the Leaves of Combretum micranthum Exert Antiviral Activity against Tomato Brown Rugose Fruit Virus (ToBRFV)
open7noTomato brown rugose fruit virus (ToBRFV) is a new damaging plant virus of great interest
from both an economical and research point of view. ToBRFV is transmitted by contact, remains
infective for months, and to-date, no resistant cultivars have been developed. Due to the relevance
of this virus, new effective, sustainable, and operator-safe antiviral agents are needed. Thus, 4-
hydroxybenzoic acid was identified as the main product of the alkaline autoxidation at high
temperature of the methanolic extract of the leaves of C. micranthum, known for antiviral activity.
The autoxidized extract and 4-hydroxybenzoic acid were assayed in in vitro experiments, in
combination with a mechanical inoculation test of tomato plants. Catechinic acid, a common
product of rearrangement of catechins in hot alkaline solution, was also tested. Degradation of the
viral particles, evidenced by the absence of detectable ToBRFV RNA and the loss of virus infectivity,
as a possible consequence of disassembly of the virus coat protein (CP), were shown. Homology
modeling was then applied to prepare the protein model of ToBRFV CP, and its structure was
optimized. Molecular docking simulation showed the interactions of the two compounds, with the
amino acid residues responsible for CP-CP interactions. Catechinic acid showed the best binding
energy value in comparison with ribavirin, an anti-tobamovirus agent.openValeria Iobbi, Anna Paola Lanteri, Andrea Minuto, Valentina Santoro, Giuseppe Ferrea, Paola Fossa, Angela BisioIobbi, Valeria; Paola Lanteri, Anna; Minuto, Andrea; Santoro, Valentina; Ferrea, Giuseppe; Fossa, Paola; Bisio, Angel
Platelet Antiaggregating Activity and Chemical Constituents of Salvia x Jamensis J. Compton
A phytochemical study has been carried out on the surface exudate of Salvia x jamensis, which showed a significant platelet antiaggregating activity. The known compounds isopimaric acid (2), 14-α-hydroxy-isopimaric acid (3), 3β-hydroxy-isopimaric acid (4), 7,8β-dihydrosalviacoccin (5), betulinic acid (6), and ursolic acid (7) were isolated together with the new diterpene 1. The structure of 1 was determined as 15,16-epoxy-cleroda-3-en-7α,10β-dihydroxy-12,17;19,18-diolide on the basis of spectroscopic data analysis. Among all tested compounds, 2 showed a significant concentration-dependent antiaggregating activity when ADP (3 μM) was used as agonist on rat platelets. Conversely, 1 increased ADP–induced platelet aggregation
The novel diterpene 7\u3b2-acetoxy-20-hydroxy-19,20-epoxyroyleanone from Salvia corrugata shows complex cytotoxic activities against human breast epithelial cells
Aims
The aim of this study was the characterization of the in vitro cytotoxic properties of a recently isolated diterpene compound, 7\u3b2-acetoxy-20-hydroxy-19,20-epoxyroyleanone (compound 1), extracted from Salvia corrugata, versus human cell lines.
Main Methods
We used as model study immortalized breast epithelial cells MCF10A and two ERBB2+ breast cancer (BCa) cell lines, SKBR-3 and BT474. Compound 1 was isolated by methanolic extraction from regenerated shoots of Salvia corrugata Vahl, and purified by high pressure liquid chromatography (HPLC). Flow cytometry (FCM) was employed for cell cycle, apoptosis and reactive oxygen species (ROS) analysis. Cell morphology was assessed by immunofluorescence and transmission electron microscopy (TEM).
Key Findings
Compound 1 inhibited cell survival of all breast cell lines. In particular, compound 1 promoted cell cycle arrest in the G0/G1 phase and apoptosis along with impairment of the mitochondrial function, which was reflected in a gross alteration of the mitochondrial network structure. Furthermore, we also detected a potent activation of the ERK1/2 kinase, which suggested the induction of reactive oxygen species (ROS). Partial rescue of survival obtained with n-acetylcysteine (NAC) when coadminstered with compound 1 further supported a contribution of ROS mediated mechanisms to the growth-arrest and proapoptotic activity of compound 1 in both BCa cell lines. ROS production was indeed confirmed in SKBR-3.
Significance
Our findings show that compound 1 has a cytotoxic activity against both human normal and cancer cell lines derived from breast epithelia, which is mediated by ROS generation and mitochondrial damage
Phytotoxic activity of Salvia x jamensis.
A study has been carried out on the surface exudate of Salvia x jamensis, which showed a significant phytotoxic activity against Papaver rhoeas L. and Avena sativa L.. Bioguided separation of the exudate yielded active fractions from which 3β-hydroxy-isopimaric acid (1), hautriwaic acid (2), betulinic acid (3), 7,8β-dihydrosalviacoccin (4), isopimaric acid (5), 14α-hydroxy-isopimaric acid (7), 15,16-epoxy-7α,10β-dihydroxy-clerod-3,13(16),14-trien-17,12;18,19-diolide (8), cirsiliol (5,3′,4′-trihydroxy-6,7-dimethoxyflavone, 9) and two new neoclerodane diterpenes (6 and 10) were isolated. The structures of 6 and 10 were identified as 15,16-epoxy-10β-hydroxy-clerod-3,13(16),14-trien-17,12;18,19-diolide and 15,16-epoxy-7α,10-dihydroxy-clerod-2,13(16),14-trien-17,12;18,19-diolide respectively on the basis of spectroscopic data analysis. All compounds, but 7, 8 and 10, were active in inhibiting the germination of the tested species
Cooperative antitumor activities of carnosic acid and Trastuzumab in ERBB2+ breast cancer cells
Background: ERBB2 is overexpressed in up to 20\u201330% of human breast cancers (BCs), and it is associated with
aggressive disease. Trastuzumab (Tz), a humanized monoclonal antibody, improves the prognosis associated with
ERBB2-amplified BCs. However, the development of resistance remains a significant challenge. Carnosic acid
(CA) is a diterpene found in rosemary and sage, endowed with anticancer properties. In this in vitro study,
we have investigated whether Tz and CA have cooperative effects on cell survival of ERBB2 overexpressing
(ERBB2+) cells and whether CA might restore Tz sensitivity in Tz-resistant cells.
Methods: We have studied BC cell migration and survival upon CA and Tz treatment. In particular, migration
ability was assessed by transwell assay while cell survival was assessed by MTT assay. In addition, we have performed cell
cycle and apoptosis analysis by high-resolution DNA flow cytometry and annexin-V, resazurin and sytox blue staining by
flow cytometry, respectively. The expression of proteins involved in cell cycle progression, ERBB2 signaling
pathway, and autophagy was evaluated by immunoblot and immunofluorescence analysis. Cellular structures
relevant to the endosome/lysosome and autophagy pathways have been studied by immunofluorescence and
transmission electron microscopy.
Results: We report that, in ERBB2+ BC cells, CA reversibly enhances Tz inhibition of cell survival, cooperatively
inhibits cell migration and induces cell cycle arrest in G0/G1. These events are accompanied by ERBB2 downregulation,
deregulation of the PI3K/AKT/mTOR signaling pathway and up-regulation of both CDKN1A/p21WAF1
and CDKN1B/p27KIP1. Furthermore, we have demonstrated that CA impairs late autophagy and causes derangement of
the lysosomal compartment as shown by up-regulation of SQSTM1/p62 and ultrastructural analysis. Accordingly, we
have found that CA restores, at least in part, sensitivity to Tz in SKBR-3 Tz-resistant cell line.
Conclusions: Our data demonstrate the cooperation between CA and Tz in inhibiting cell migration and survival of
ERBB2+ BC cells that warrant further studies to establish if CA or CA derivatives may be useful in vivo in the treatment
of ERBB2+ cancers
Exploring the Anticancer Potential of Premna resinosa (Hochst.) Leaf Surface Extract: Discovering New Diterpenes as Heat Shock Protein 70 (Hsp70) Binding Agents
Premna, a genus consisting of approximately 200 species, predominantly thrives in tropical and subtropical areas. Many of these species have been utilized in ethnopharmacology for diverse medicinal applications. In Saudi Arabia, Premna resinosa (Hochst.) Schauer (Lamiaceae) grows wildly, and its slightly viscid leaves are attributed to the production of leaf accession. In this study, we aimed to extract the surface accession from fresh leaves using dichloromethane to evaluate the anticancer potential. The plant exudate yielded two previously unknown labdane diterpenes, Premnaresone A and B, in addition to three already described congeners and four known flavonoids. The isolation process was accomplished using a combination of silica gel column chromatography and semi preparative HPLC, the structures of which were identified by NMR and HRESIMS analyses and a comparison with the literature data of associated compounds. Furthermore, we employed a density functional theory (DFT)/NMR approach to suggest the relative configuration of different compounds. Consequently, we investigated the possibility of developing new chaperone inhibitors by subjecting diterpenes 1–5 to a Surface Plasmon Resonance-screening, based on the knowledge that oridonin, a diterpene, interacts with Heat Shock Protein 70 (Hsp70) 1A in cancer cells. Additionally, we studied the anti-proliferative activity of compounds 1–5 on human Jurkat (human T-cell lymphoma) and HeLa (epithelial carcinoma) cell lines, where diterpene 3 exhibited activity in Jurkat cell lines after 48 h, with an IC50 of 15.21 ± 1.0 µM. Molecular docking and dynamic simulations revealed a robust interaction between compound 3 and Hsp70 key residues
Relative Stereochemistry of a Diterpene from Salvia cinnabarina
The relative stereochemistry of 3,4-secoisopimara-4(18),7,15-triene-3-oic acid, a diterpenoid with antispasmodic, hypotensive and antibacterial activities isolated from Salvia cinnabarina, was determined by an X-ray diffraction analysis of a single crystal of a suitable crystalline derivative
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