Antioxidant, enzyme-inhibitory and antitumor activity of the wild dietary plant Muscari comosum (L.) Mill.

Conventional medicines used to treat obesity and cancer frequently exhibit high side effects, so that researchers are focusing on new therapies and drugs based on natural products. Total extracts from bulbs of Muscari comosum were tested for i) free radical scavenging activity, ii) in vitro enzymatic inhibition of pancreatic α-amylase and lipase, and iii) inhibition of the growth of breast adenocarcinoma cells. Three treatments were considered: bulbs boiled in water for 15 min (traditional cooking method; BB); bulbs steam-cooked for 15 min (alternative cooking method; SB); raw bulbs (RB). The polyphenol content and antioxidant capacity of bulb extracts were related to the inhibition of pancreatic lipase and α-amylase, whose activities have been found to have a half maximal inhibitory concentration (IC50) of 0.28, 2.14 and 3.22 mg/mL for lipase, and 0.16, 0.73 and 0.69 mg/mL for α-amylase in RB, SB and BB, respectively. The analysis on breast adenocarcinoma MCF-7 cells revealed that RB extracts, and in a lesser extent BB, exerted a dose-dependent inhibition on cell proliferation. Considering that the potential of natural products for the treatment of obesity are under exploration, M. comosum could be an excellent plant for the development of future anti-obesity drugs, also able to prevent cancer

Protective effect of Hypericum calabricum Sprengel on oxidative damage and its inhibition of nitric oxide in lipopolysaccharide-stimulated RAW 264.7 macrophages

The present study shows for the fi rst time the phenolic composition and the in vitro properties (antioxidant and inhibition of nitric oxide production) of Hypericum calabricum Sprengel collected in Italy. The content of hypericins (hypericin and pseudohypericin), hyperforin, fl avonoids (rutin, hyperoside, isoquercetrin, quercitrin, quercetin and biapigenin) and chlorogenic acid of H. calabricum, have been determined. The ethyl acetate fraction from the aerial parts of H. calabricum exhibited activity against the radical 1,1-diphenyl-2picrylhydrazyl (DPPH) with IC 50 value of 1.6 μg/ml. The test for inhibition of nitric oxide (NO) production was performed using the murine monocytic macrophage cell line RAW 264.7. The ethyl acetate fraction had signifi cant activity with an IC 50 value of 102 μg/ml and this might indicate that it would have an anti-infl ammatory effect in vivo

Effects of Saponins on Lipid Metabolism: A Review of Potential Health Benefits in the Treatment of Obesity

Obesity is one of the greatest public health problems. This complex condition has reached epidemic proportions in many parts of the world, and it constitutes a risk factor for several chronic disorders, such as hypertension, cardiovascular diseases and type 2 diabetes. In the last few decades, several studies dealt with the potential effects of natural products as new safe and effective tools for body weight control. Saponins are naturally-occurring surface-active glycosides, mainly produced by plants, whose structure consists of a sugar moiety linked to a hydrophobic aglycone (a steroid or a triterpene). Many pharmacological properties have been reported for these compounds, such as anti-inflammatory, immunostimulant, hypocholesterolemic, hypoglycemic, antifungal and cytotoxic activities. The aim of this review is to provide an overview of recent studies about the anti-obesity therapeutic potential of saponins isolated from medicinal plants. Results on the in vitro and in vivo activity of this class of phytochemicals are here presented and discussed. The most interesting findings about their possible mechanism of action and their potential health benefits in the treatment of obesity are reported, as well

Assessment of Photo-Induced Cytotoxic Activity of Cachrys sicula and Cachrys libanotis Enriched-Coumarin Extracts against Human Melanoma Cells

Photochemotherapy is one of the most interesting current therapeutic approaches for the treatment of melanoma. Different classes of naturally occurring phytochemicals demonstrated interesting photoactive properties. The aim of this study was to evaluate the photocytotoxic potential of two Cachrys species from Southern Italy: C. sicula and C. libanotis (Apiaceae). The enriched-coumarin extracts were obtained from aerial parts through both traditional maceration and pressurized cyclic solid-liquid (PCSL) extraction using Naviglio extractor®. Qualitative and quantitative analyses of furanocoumarins were performed with GC-MS. The photocytotoxic effects were verified on C32 melanoma cells irradiated at a dose of 1.08 J/cm2. The apoptotic responses were also assessed. Moreover, phenolic content and the in vitro antioxidant potential were estimated. Xanthotoxin, bergapten, and isopimpinellin were identified. All the samples induced concentration-dependent photocytotoxic effects (IC50 ranging from 3.16 to 18.18 μg/mL). The C. libanotis sample obtained with Naviglio extractor® was the most effective one (IC50 = 3.16 ± 0.21 μg/mL), followed by C. sicula sample obtained with the same technique (IC50 = 8.83 ± 0.20 μg/mL). Both Cachrys samples obtained through PCSL induced up-regulation of apoptotic signals such as BAX (Bcl2-associated X protein) and PARP (poly ADP-ribose polymerase) cleavage. Moreover, these samples proved to be more photoactive, giving a greater upregulation of p21 protein in the presence of UVA radiation. Obtained results suggest that investigated species could be promising candidates for further investigations aimed to find new potential drugs for the photochemotherapy of skin cancer

Bioactive phytonutrients (omega fatty acids, tocopherols, polyphenols), in vitro inhibition of nitric oxide production and free radical scavenging activity of non-cultivated Mediterranean vegetables

Hydroalcoholic extracts from 18 non-cultivated vegetables traditionally consumed in Southern Italy were tested for their free radical scavenging activity (FRSA) in the DPPH (1,1-diphenyl-2-picrylhydrazil radical) screening assay and for their in vitro inhibition of nitric oxide (NO) production. The strongest activity was shown for Rubus caesius (leaves), Mentha spicata subsp. glabra (leaves) and Origanum vulgare subsp. viridulum (stems and leaves) with IC 50 values of 5, 6, 8 μg/ml, respectively. Extracts from non-cultivated Foeniculum vulgare subsp. piperitum (seeds), Amaranthus retroflexus (leaves) and M. spicata subsp. glabra (leaves) showed high in vitro inhibition of nitric oxide production, with an activity comparable to a reference drug, indomethacin. A significant cytotoxic effect was shown for the seeds of F. vulgare subsp. piperitum. A. retroflexus (leaves) presented the highest content in linoleic acid. R. caesius and M. spicata subsp. glabra had relatively high polyphenols content, 482 and 334 mg/g of extract, respectively. © 2011 Elsevier Ltd. All rights reserved.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Identification by Molecular Docking of Homoisoflavones from Leopoldia comosa as Ligands of Estrogen Receptors

The physiological responses to estrogen hormones are mediated within specific tissues by at least two distinct receptors, ERα and ERβ. Several natural and synthetic molecules show activity by interacting with these proteins. In particular, a number of vegetal compounds known as phytoestrogens shows estrogenic or anti-estrogenic activity. The majority of these compounds belongs to the isoflavones family and the most representative one, genistein, shows anti-proliferative effects on various hormone-sensitive cancer cells, including breast, ovarian and prostate cancer. In this work we describe the identification of structurally related homoisoflavones isolated from Leopoldia comosa (L.) Parl. (L. comosa), a perennial bulbous plant, potentially useful as hormonal substitutes or complements in cancer treatments. Two of these compounds have been selected as potential ligands of estrogen receptors (ERs) and the interaction with both isoforms of estrogen receptors have been investigated through molecular docking on their crystallographic structures. The results provide evidence of the binding of these compounds to the target receptors and their interactions with key residues of the active sites of the two proteins, and thus they could represent suitable leads for the development of novel tools for the dissection of ER signaling and the development of new pharmacological treatments in hormone-sensitive cancers