Vasomodulating potential of mediterranean wild plant extracts

The Anti-Inflammatory Potential of an Ethanolic Extract from Sarcopoterium spinosum Fruits for Protection and/or Counteraction against Oxidative Stress in Dysfunctional Endothelial Cells

Plants and plant extracts are a relevant source of bioactive compounds widely employed as functional foods. In the Mediterranean area, the shrub Sarcopoterium spinosum is traditionally used as an herbal medicine for weight loss and a diabetes treatment. Inflammation is a protective mechanism involved in the development of many pathological conditions, including cardiovascular diseases. The present study aimed to investigate in vitro the antioxidant and cytoprotective properties of an ethanolic extract from S. spinosum fruits (SEE) in a cellular model of endothelium dysfunction. Corilagin and quercetin are two polyphenols abundant in SEE and were tested for comparison. The exposure of HECV cells for 24 h to 30 µM hydrogen peroxide (H2O2) lead to an oxidative stress condition. When HECV cells were treated with 10 µg/mL of SEE or single compounds after or before the oxidative insult, the results showed their ability to (i) decrease the reactive oxygen species (ROS) production quantified using fluorometric analysis and the lipid peroxidation measured with a spectrophotometric assay; (ii) rescue both the glutathione reduced to oxidized (GSH/GSSG) ratio and nitric oxide impair and the protein denaturation; and (iii) accelerate the wound repair measured using a T-scratch assay. Taken together, our findings indicate that the ethanolic extract from S. spinosum fruits could be a potential candidate for nutraceutical application.

Protective Role of Natural Products in Glioblastoma Multiforme: A Focus on Nitric Oxide Pathway

In spite of therapeutic modalities such as surgical resection, chemotherapy, and radiotherapy, Glioblastoma Multiforme (GBM) remains an incurable fatal disease. This necessitates further therapeutic options that could enhance the efficacy of existing modalities. Nitric Oxide (NO), a short-lived small molecule, has been revealed to play a crucial role in the pathophysiology of GBM. Several studies have demonstrated that NO is involved in apoptosis, metastasis, cellular proliferation, angiogenesis, invasion, and many other processes implicated in GBM pathobiology. Herein, we elaborate on the role of NO as a therapeutic target in GBM and discuss some natural products affecting the NO signaling pathway.

Mechanisms of Medicinal Plant Activity on Nitric Oxide (NO) Bioavailability as Prospective Treatments for Atherosclerosis

Background and objective:

Atherosclerosis is one of the leading causes of human morbidity globally and reduced bioavailability of vascular nitric oxide (NO) has a critical role in the progression and development of the atherosclerotic disease. Loss of NO bioavailability, for example via a deficiency of the substrate (L-arginine) or cofactors for endothelial nitric oxide synthase (eNOS), invariably leads to detrimental vascular effects such as impaired endothelial function and increased smooth muscle cell proliferation, deficiency of the substrate (Larginine) or cofactors for eNOS. Various medicinal plants and their bioactive compounds or secondary metabolites with fewer side effects are potentially implicated in preventing cardiovascular disease by increasing NO bioavailability, thereby ameliorating endothelial dysfunction. In this review, we describe the most notable medicinal plants and their bioactive compounds that may be appropriate for enhancing NO bioavailability, and treatment of atherosclerosis.

Methods:

The material in this article was obtained from noteworthy scientific databases, including Web of Science, PubMed, Science Direct, Scopus and Google Scholar.

Results:

Medicinal plants and their bioactive compounds influence NO production through diverse mechanisms including the activation of the nuclear factor kappa B (NF-κB) signaling pathway, activating protein kinase C (PKC)-α, stimulating protein tyrosine kinase (PTK), reducing the conversion of nitrite to NO via nitrate-nitrite reduction pathways, induction of eNOS, activating the phosphatidylinositol 3-kinase (PI3K)/serine threonine protein kinase B (AKT) (PI3K/AKT/eNOS/NO) pathway and decreasing oxidative stress.

Conclusion:

Medicinal plants and/or their constituent bioactive compounds may be considered as safe therapeutic options for enhancing NO bioavailability and prospective preventative therapy for atherosclerosis.

A Review of the Benefits of Satureja Species on Metabolic Syndrome and Their Possible Mechanisms of Action

Metabolic syndrome, also known as insulin resistance disorder, is the simultaneous manifestation of multiple metabolic disorders in an individual. The present-day complementary and alternative therapies suggest several medicinal herbs that may have the potential to improve one or multiple complications of metabolic syndrome. All of them have their own limitations in efficacy and unwanted effects. Therefore, we reviewed species of Satureja as widespread medicinal herbs and potentially good remedies for metabolic syndrome. We reviewed literature found in PubMed and the ISI Web of Knowledge with the key word Satureja in the title. The influence of any species of Satureja on any disease or syndrome, enzymatic, metabolic, or physiological pathways, in human, animals, or in vitro conditions related to any characteristics of metabolic syndrome were considered. The main outcomes of treatment with Satureja species were categorized, and the possible mechanisms of action are discussed in this article.

Artichoke, cynarin and cyanidin downregulate the expression of inducible nitric oxide synthase in human coronary smooth muscle cells

Artichoke (Cynara scolymus L.) is one of the world’s oldest medicinal plants with multiple health benefits. We have previously shown that artichoke leaf extracts and artichoke flavonoids upregulate the gene expression of endothelial-type nitric oxide synthase (eNOS) in human endothelial cells. Whereas NO produced by the eNOS is a vasoprotective molecule, NO derived from the inducible iNOS plays a pro-inflammatory role in the vasculature. The present study was aimed to investigate the effects of artichoke on iNOS expression in human coronary artery smooth muscle cells (HCASMC). Incubation of HCASMC with a cytokine mixture led to an induction of iNOS mRNA expression. This iNOS induction was concentration- and time-dependently inhibited by an artichoke leaf extract (1–100 µg/mL, 6 h or 24 h). Consistently, the artichoke leaf extract also reduced cytokine-induced iNOS promoter activation and iNOS protein expression. In addition, treatment of HCASMC with four well-known artichoke compounds (cynarin > cyanidin > luteolin ≈ cynaroside) led to a downregulation iNOS mRNA and protein expression, with cynarin being the most potent one. In conclusion, artichoke contains both eNOS-upregulating and iNOS-downregulating compounds. Such compounds may contribute to the beneficial effects of artichoke and may per se have therapeutic potentials.

Mediterranean wild plants reduce postprandial platelet aggregation in patients with metabolic syndrome

Postprandial platelet hyperactivity and aggregation play a crucial role in the pathogenesis of metabolic syndrome. The purpose of the present study was to evaluate the effect of boiled wild plants consumption on the postprandial platelet aggregation in metabolic syndrome patients. Patients consumed 5 meals in a random order (ie, 4 wild plant meals, namely, Reichardia picroides [RP], Cynara cardunculus, Urospermum picroides [UP], and Chrysanthemum coronarium, and a control meal, which contained no wild plants). Several biochemical indices as well as platelet activating factor (PAF)- and adenosine diphosphate-induced ex vivo platelet aggregation were measured postprandially. Moreover, the ability of plants extract to inhibit rabbit platelet aggregation was tested in vitro. The consumption of RP and UP meals significantly reduced ex vivo adenosine diphosphate-induced postprandial platelet aggregation compared with the control meal. The consumption of UP meals significantly reduced the ex vivo PAF-induced platelet aggregation postprandially. Both UP and RP extracts significantly inhibited PAF-induced rabbit platelet aggregation in vitro. Wild plants consumption reduced postprandial platelet hyperaggregability of metabolic syndrome patients, which may account for their healthy effects.

Antioxidants to enhance fertility: role of eNOS and potential benefits

The use of antioxidants is now often used as a pharmacological adjunct to limit infertility. Indeed, the lay public rightly perceives oxidative stress and, thus, antioxidant treatment as important modulators of infertility. While the direct effects of antioxidant treatment on the quality of semen and oocytes are still under investigation, a significant body of evidence points to loss of vascular tone as a root-cause of erectile dysfunction and, possibly, alterations to female reproduction. In this article, we will critically review the often neglected link between vascular dysfunction and infertility. A particular emphasis will be on the potential use of antioxidants to increase fertility and promote conception.

Cellulite: Is there a role for injectables?

BACKGROUND

Cellulite describes the cutaneous dimpling of the thighs, buttocks, and hips that is seen predominately in women. Current evidence suggests that structural differences in fat architecture between the sexes account for its appearance. Mesotherapy, a method of delivering medication locally with the use of numerous cutaneous injections, has recently become a popular method to purportedly treat the condition.

METHODS

An overview of cellulite and adipocyte physiology, with a literature review and appraisal of compounds commonly used in mesotherapy.

RESULTS

Experimental studies using individual mesotherapy ingredients for other conditions suggest a number of mechanisms, including lipolysis, disrupting connective tissue and augmenting circulation, which may theoretically improve cellulite. Peer-reviewed studies have not evaluated whether these effects translate clinically.

CONCLUSIONS

Until further studies are performed, patients considering mesotherapy for cellulite must be aware that the substances currently being injected to treat this cosmetically disturbing, but medically benign, condition have not been thoroughly evaluated for safety or efficacy.

Nitric oxide selective electrodes

Since nitric oxide (NO) was identified as the endothelial-derived relaxing factor in the late 1980s, many approaches have attempted to provide an adequate means for measuring physiological levels of NO. Although several techniques have been successful in achieving this aim, the electrochemical method has proved the only technique that can reliably measure physiological levels of NO in vitro, in vivo, and in real time. We describe here the development of electrochemical sensors for NO, including the fabrication of sensors, the detection principle, calibration, detection limits, selectivity, and response time. Furthermore, we look at the many experimental applications where NO selective electrodes have been successfully used.

Antioxidant activity of wild plants collected in valsesia, an alpine region of Northern Italy

A selection of wild plants collected in Valsesia (Northwest Italy) was screened for their in vitro antioxidant activity. Aerial parts of selected plants were dried at room temperature and powdered. Then, four sequential extractions were performed with increasing polarity solvents, i.e. n-hexane, chloroform, chloroform-methanol (9:1, v/v) and methanol. By employing different assays, it was shown that all the methanol extracts of the samples collected were endowed with antioxidant activity, though, as expected, their potency varied according to the different tests. In particular, plants of the Thymus and Achillea genus displayed the highest activity. Given that a diet rich in wild plants is associated with a reduced incidence of degenerative diseases, such as atherosclerosis and cancer, this study suggests that some Valsesia plants could be pharmaceutically exploited.

Wild artichoke prevents the age-associated loss of vasomotor function

Endothelial dysfunction, which is more often observed in conduit arteries such as the aorta, carotid, femoral, and brachial arteries, is largely due to alterations in cellular signal transduction initiated by an escalating cycle of damage triggered by oxidative stress. This phenomenon is exacerbated in the elderly, where a progressive loss of vascular endothelial function and concurrent loss of vasomotor control is frequent. In a previous study, we demonstrated that the wild artichoke (Cynara cardunculus) is able to increase the production of the vasorelaxant factor nitric oxide by cultured aortic endothelial cells. We now extended that study to verify (1) the vasorelaxant potential of C. cardunculus on isolated rat aortic rings and (2) whether the vasomodulating properties of C. cardunculus are maintained in vivo, after administration to aged rats. The results demonstrate that the wild artichoke and its main components, namely, luteolin and apigenin, improve aortic relaxation when added to the incubation bath. Moreover, the feeding of wild artichoke [10 mg (kg of polyphenols)(-1) day(-1)] to aged rats significantly restores proper vasomotion, to a degree similar to that observed in young animals. This study provides further justification to the advice to consume wild greens as part of a balanced diet and suggests that close attention should be paid to the diet of the elderly, because it can effectively modulate important parameters of cardiovascular risk.

Understanding local Mediterranean diets: A multidisciplinary pharmacological and ethnobotanical approach

Epidemiological data indicate a beneficial effect of Mediterranean diets on human health, especially on the prevalence of cardiovascular disease. These observations are supported by recent intervention studies. However, very little is known about the current role of local Mediterranean food products, which are consumed on a less regular basis and their contribution to a healthy diet. The European consortium "Local Food-Nutraceuticals" collected 127 locally consumed wild or semi-wild plants in three Mediterranean countries, i.e. Greece, Italy, and Spain, in order to assess their ethnobotanical features as well as their biological activities. The project also includes a second line of research, the study of local conceptions about these food resources. All pharmacological assays were conducted with ethanolic extracts prepared from the dried plant material. The biological activities of the extracts were assessed with the following 12 different assays covering a broad range of mechanisms considered crucial in the pathology of chronic, aging-related diseases. Four antioxidant tests: DPPH scavenging, prevention of oxyhaemoglobin bleaching, prevention of lipid peroxidation (malondialdehyde formation), and protection from DNA damage (Comet assay); three enzyme inhibition tests: inhibition of xanthine oxidase, inhibition of myeloperoxidase-catalysed guaiacol oxidation as well as the inhibition of acetylcholine esterase; one test investigating the inhibition of cytokine-induced cell activation (including the extracts' potential cytotoxicity); one assay measuring the anti-proliferation potential; one test assessing the anti-diabetic activity (PPARgamma) as well as one assay investigating the extracts' effect on mood disorder-related biochemical parameters (hSERT). Furthermore, the polyphenol content of all extracts was determined using the Folin-Ciocalteaus method. The assays revealed diverse biological effects for the tested extracts ranging from no activity to almost complete inhibition/activation. Moreover, the experimental matrix led to the identification of a sub-set of extracts, i.e. Berberis vulgaris, Reichardia picroides, Scandix australis, Satureja montana, Thymus piperella, Lythrum salicaria and Vitis vinifera, showing high activity in a broad range of assays. In summary, the in vitro observed modulations and effects exerted by extracts derived from local food plants suggest that these plants may contribute to the observed better aging of rural Mediterranean populations.

Hypochlorous acid scavenging properties of local Mediterranean plant foods

Oxidative modification of low density lipoprotein (LDL) is involved in the pathogenesis of atherosclerosis and coronary heart disease, which are low in the Mediterranean area possibly due to a high dietary proportion of plant foods. Ethanolic extracts were prepared from more than 120 Mediterranean edible plants collected in remote areas (which maintain their traditional diet) and their antioxidant potential was studied. Extracts derived from Agaricus campestris, Cynara cardunculus, Thymus pulegioides, and Vicia faba were subjected to further analysis in this study. The extracts' potential to scavenge the DPPH radical (2,2-diphenyl-1-picrylhydrazyl radical) and hypochlorous acid (HOCl), as well as their antioxidant capacity, was comparable to the those obtained for standard antioxidants (e.g., quercetin, Trolox). Myeloperoxidase (MPO) catalyzes the production of the highly chlorinating and oxidizing agent HOCl, which reacts with the LDL apoprotein moiety, leading to the derivatization of its aminoacidic residues. Coincubation with extracts significantly prevented HOCl-induced modification of the LDL residue tryptophan, whereas higher concentrations were required to retard lysine damage. Moreover, the extracts inhibited MPO-catalyzed guaiacol oxidation in a concentration-dependent manner in a cell-free assay but, in contrast, did not affect MPO activity in isolated human neutrophils. MPO is also known to facilitate nitric dioxide oxidation. The formation of 3-nitrotyrosine was significantly lower in bovine endothelial aortic cells incubated with C. cardunculus or T. pulegioides. In synthesis, our study shows that local Mediterranean plant foods prevent HOCl toxicity in vitro and, thus, suggests further mechanisms responsible for the reported health-beneficial effect of the Mediterranean diet.