Fenugreek (Trigonella Foenum-Graecum) Seed Flour and Diosgenin Preserve Endothelium-Dependent Arterial Relaxation in a Rat Model of Early-Stage Metabolic Syndrome.

Fenugreek is a common herb possessing several bioactive components including diosgenin. Here, dietary fenugreek seed flour and diosgenin were evaluated on a model of endothelium-dependent vasorelaxation by abdominal aortas isolated from rats receiving high-fat, high-sugar diet (HFHSD). 60 male Wistar rats were randomized into six groups: (i) negative control getting conventional rat feed regimen; (ii) positive control receiving HFHSD; (iii) a test group fed 2 g/kg bw/day fenugreek seed flour (containing 10 mg/kg bw/day diosgenin) + HFHSD; (iv) three test groups fed 1, 10 and 50 mg/kg bw/day diosgenin + HFHSD. Alimentary treatments were carried out for six weeks. The abdominal aortas were isolated, and 2 mm wide rings were sectioned off and mounted at a resting tension of 10 mN in organ baths containing Krebs solution (36 °C) exposed to 95% O2 and 5% CO2. After 60-min incubation, a norepinephrine concentration-response (E/c) curve was generated to determine their half-maximal effective concentration (EC50) value. After 60-min wash-out, a pre-contraction with norepinephrine EC50 was made, followed by an acetylcholine E/c curve. Plasma glutathione levels, glutathione-handling enzyme activities and blood antioxidant capacities were also determined. HFHSD significantly decreased the dilatory response to acetylcholine and increased plasma glutathione levels and these effects were significantly reversed by fenugreek seed flour, 10 and 50 mg/kg bw/day diosgenin. Both fenugreek and diosgenin treatments prevent HFHSD-induced endothelial dysfunction and redox changes. As fenugreek treatment was more effective at lower acetylcholine concentrations than diosgenin treatments, components of fenugreek other than diosgenin may contribute to the beneficial effects of dietary fenugreek seed flour.

Insulin-Sensitizer Effects of Fenugreek Seeds in Parallel with Changes in Plasma MCH Levels in Healthy Volunteers.

In developed, developing and low-income countries alike, type 2 diabetes mellitus (T2DM) is one of the most common chronic diseases, the severity of which is substantially a consequence of multiple organ complications that occur due to long-term progression of the disease before diagnosis and treatment. Despite enormous investment into the characterization of the disease, its long-term management remains problematic, with those afflicted enduring significant degradation in quality-of-life. Current research efforts into the etiology and pathogenesis of T2DM, are focused on defining aberrations in cellular physiology that result in development of insulin resistance and strategies for increasing insulin sensitivity, along with downstream effects on T2DM pathogenesis. Ongoing use of plant-derived naturally occurring materials to delay the onset of the disease or alleviate symptoms is viewed by clinicians as particularly desirable due to well-established efficacy and minimal toxicity of such preparations, along with generally lower per-patient costs, in comparison to many modern pharmaceuticals. A particularly attractive candidate in this respect, is fenugreek, a plant that has been used as a flavouring in human diet through recorded history. The present study assessed the insulin-sensitizing effect of fenugreek seeds in a cohort of human volunteers, and tested a hypothesis that melanin-concentrating hormone (MCH) acts as a critical determinant of this effect. A test of the hypothesis was undertaken using a hyperinsulinemic euglycemic glucose clamp approach to assess insulin sensitivity in response to oral administration of a fenugreek seed preparation to healthy subjects. Outcomes of these evaluations demonstrated significant improvement in glucose tolerance, especially in patients with impaired glucose responses. Outcome data further suggested that fenugreek seed intake-mediated improvement in insulin sensitivity correlated with reduction in MCH levels.

Self-Nanoemulsifying Drug Delivery Systems Containing Plantago lanceolata-An Assessment of Their Antioxidant and Antiinflammatory Effects.

The most important components of Plantago lanceolata L. leaves are catalpol, aucubin, and acteoside (=verbascoside). These bioactive compounds possess different pharmacological effects: anti-inflammatory, antioxidant, antineoplastic, and hepatoprotective. The aim of this study was to protect Plantago lanceolata extract from hydrolysis and to improve its antioxidant effect using self-nano-emulsifying drug delivery systems (SNEDDS). Eight SNEDDS compositions were prepared, and their physical properties, in vitro cytotoxicity, and in vivo AST/ALT values were investigated. MTT cell viability assay was performed on Caco-2 cells. The well-diluted samples (200 to 1000-fold dilutions) proved to be non-cytotoxic. The acute administration of PL-SNEDDS compositions resulted in minor changes in hepatic markers (AST, ALT), except for compositions 4 and 8 due to their high Transcutol contents (80%). The non-toxic compositions showed a significant increase in free radical scavenger activity measured by the DPPH test compared to the blank SNEDDS. An indirect dissolution test was performed, based on the result of the DPPH antioxidant assay; the dissolution profiles of Plantago lancolata extract were statistically different from each SNEDDS. The anti-inflammatory effect of PL-SNEDDS compositions was confirmed by the ear inflammation test. For the complete examination period, all compositions decreased ear edema as compared to the positive (untreated) control. It can be concluded that PL-SNEDDS compositions could be used to deliver active natural compounds in a stable, efficient, and safe manner.

Protective Effect of Prunus Cerasus (Sour Cherry) Seed Extract on the Recovery of Ischemia/Reperfusion-Induced Retinal Damage in Zucker Diabetic Fatty Rat.

Among diabetes patients, ophthalmological complications are very frequent. High blood glucose and (consequential) ischemia-reperfusion (I/R) injury contribute significantly to the severity of retinopathies. Diabetic retinopathy is among the leading causes of blindness. Our study demonstrates the effect of sour cherry seed extract (SCSE) on blood glucose and function of the retina with electroretinography (ERG) in a diabetic setting with or without ischemia-reperfusion (I/R) injury in Zucker Diabetic Fatty (ZDF) rats. Our results prove that the SCSE has a retinoprotective effect in diabetic rats: according to ERG measurements, SCSE treatment mitigated the retinal function-damaging effect of diabetes, and proved to be protective in the diabetic eye against ischemia-reperfusion injuries of the retina. Outcomes suggest that the protective effects of SCSE may occur through several pathways, including HO-1 dependent mechanisms. The observation that SCSE treatment decreases blood glucose is also novel. These findings offer the possibility for development of novel therapeutic strategies utilizing this emerging functional food, in particular in the prevention of conditions resulting from high blood glucose or I/R injury, such as deterioration of retinal microcirculation.

Anti-Atherogenic Properties of Allium ursinum Liophylisate: Impact on Lipoprotein Homeostasis and Cardiac Biomarkers in Hypercholesterolemic Rabbits.

The present investigation evaluates the capacity of Allium ursinum (wild garlic) leaf lyophilisate (WGLL; alliin content: 0.261%) to mitigate cardiovascular damage in hypercholesterolemic rabbits. New Zealand rabbits were divided into three groups: (i) cholesterol-free rabbit chow (control); (ii) rabbit chow containing 2% cholesterol (hypercholesterolemic, HC); (iii) rabbit chow containing 2% cholesterol + 2% WGLL (hypercholesterolemic treated, HCT); for eight weeks. At the zero- and eight-week time points, echocardiographic measurements were made, along with the determination of basic serum parameters. Following the treatment period, after ischemia-reperfusion injury, hemodynamic parameters were measured using an isolated working heart model. Western blot analyses of heart tissue followed for evaluating protein expression and histochemical study for the atheroma status determination. WGLL treatment mediated increases in fractional shortening; right ventricular function; peak systolic velocity; tricuspidal annular systolic velocity in live animals; along with improved aortic and coronary flow. Western blot analysis revealed WGLL-associated increases in HO-1 protein and decreases in SOD-1 protein production. WGLL-associated decreases were observed in aortic atherosclerotic plaque coverage, plasma ApoB and the activity of LDH and CK (creatine kinase) in plasma. Plasma LDL was also significantly reduced. The results clearly demonstrate that WGLL has complex cardioprotective effects, suggesting future strategies for its use in prevention and therapy for atherosclerotic disorders.

Killing rates exerted by caspofungin in 50 % serum and its correlation with in vivo efficacy in a neutropenic murine model against Candida krusei and Candida inconspicua.

Killing rates (K) of 1-32 µg ml(-1) caspofungin were determined in RPMI-1640 and in 50 % serum using time-kill methodology against three Candida krusei (MICs of all three isolates 0.25 µg ml(-1) in RPMI-1640 and 2 µg ml(-1) in serum) and three Candida inconspicua clinical isolates (MIC ranges 0.06-0.12 µg ml(-1) in RPMI-1640 and 0.25-0.5 µg ml(-1) in serum), against C. krusei ATCC 6258 and against one C. krusei isolate that was resistant to echinocandins (MIC 8 µg ml(-1) in RPMI-1640 and 32 µg ml(-1) in serum). In RPMI-1640, the highest mean K values were observed at 4 (-1.05 h(-1)) and 16 (-0.27 h(-1)) µg ml(-1) caspofungin for C. krusei and C. inconspicua clinical isolates, respectively. In 50 % serum, mean K value ranges at 1-32 and 4-32 µg ml(-1) concentrations for C. inconspicua and C. krusei were -1.12 to -1.44 and -0.42 to -0.57 h(-1), respectively. While K values against C. krusei in RPMI-1640 and 50 % serum were comparable, serum significantly increased the killing rate against C. inconspicua (P<0.0003 for all tested concentrations). In a neutropenic murine model, daily caspofungin at 1, 2, 3, 5 and 15 mg kg(-1) significantly decreased the fungal tissue burden of C. inconspicua in the kidneys (P<0.05-0.001). Against C. krusei, doses of 3, 5 and 15 mg kg(-1) caspofungin were effective (P<0.05-0.01). All effective doses were comparably efficacious for both species. Only the highest 15 mg kg(-1) caspofungin dose was effective even against the echinocandin-resistant C. krusei isolate. In 50 % serum, killing was concentration independent at effective concentrations (≥4 and ≥1 µg ml(-1) for C. krusei and C. inconspicua, respectively), suggesting that the efficacy of dose escalation is questionable. These in vitro results were also supported by the murine model.

Cardioprotective effects of sour cherry seed extract (SCSE) on the hypercholesterolemic rabbit heart.

HYPOTHESIS: The present study evaluates the hypothesis that sour cherry seed extract (SCSE) protects against cardiovascular disease and inflammation in hypercholesterolemic rabbits, and that this protection correlates with SCSE-induced activity of heme oxygenase- 1 (HO-1), a cytoprotective enzyme contributing to oxidative stress responses. METHODS: 18 New Zealand white rabbits were divided into three groups receiving: I. cholesterol-free rabbit chow; II. chow containing 2% cholesterol; or III. 2% cholesterol plus SCSE for 16 weeks. Heart functions were monitored by echocardiography 0, 4, and 16 weeks after the initiation of cholesterol-supplemented feeding. At the 16-week time-point, isolated hearts were subjected to ischemia-reperfusion (I/R), followed by measurement of heart rate (HR), aortic flow (AF), coronary flow (CF), aortic pressure (AoP), and left ventricular developed pressure (LVDP). Myocardial infarct size was determined using triphenyl tetrazolium chloride (TTC). Quantification of fatty streaks was assessed using Sudan-III staining. Western blot analysis was used to determine the content of cytochrome c oxidase III (COX III), vascular endothelial growth factor (VEGF), and HO-1 in the myocardium. RESULTS: Relative to cholesterol-treated animals not receiving SCSE, SCSE-treated animals exhibited significantly improved cardiac function and improved peak early diastolic velocity to peak atrial velocity ratio (E'/A'), along with decreased atherosclerotic plaque formation and infarct size. Increased HO-1 and COX III protein expression and COX activity were also noted in hearts from SCSE-treated rabbits. CONCLUSIONS: This study demonstrates SCSE cardioprotective effects on hypercholesterolemic hearts. Correlation of these outcomes with HO-1 expression suggests that the effect may be mediated by activity of this enzyme. However, definitive proof of HO-1 dependence requires further investigation.

Toxicological and mutagenic analysis of Artemisia dracunculus (tarragon) extract.

Mutagenicity and liver toxicity of the herb tarragon (Artemisia dracunculus) were evaluated using single cell gel (comet) electrophoresis. Ten microlitres aliquots of peripheral venous human blood were incubated with tarragon extract, saline, or the mutagen sodium dichromate. Cell suspensions dispersed in low-melting agarose were electrophoresed in ethidium bromide. The resulting DNA migration trails were obtained using fluorescent microscopy at 400× magnification, and graded according to the mutagenicity index (MI) for each cell incubation condition. The in vivo liver toxicity of Artemisia dracunculus was assessed in the blood of mice treated orally with the extract of the herb, using alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as liver function indicators. Liver morphology was assessed using hematoxylin and eosin (HE) staining of liver tissue. The present study demonstrated a direct correlation between tarragon extract dosage and three major outcome variables: MI; serum liver enzyme activity; and liver histopathology. These outcomes are possibly due to the presence in tarragon of methylchavicol and other genotoxic compounds. These findings provide a preliminary guide for risk assessment of tarragon in diet and in possible therapeutic applications.

Protective effect of Cassia fistula fruit extract on bromobenzene-induced nephrotoxicity in mice.

The efficacy of a crude hydro-alcoholic extract of Cassia fistula (golden shower tree) fruit to protect the kidney against bromobenzene-induced toxicity was studied. Negative control mice received normal saline; positive control mice were given 460 mg/kg of bromobenzene; Cassia fistula treated mice received 200, 400, 600 and 800 mg/kg of Cassia fistula fruit extract followed by 460 mg/kg bromobenzene (daily by oral gavage for 10 days). On the 11th day, the mice were sacrificed, blood samples were obtained to assess blood urea nitrogen (BUN) and creatinine levels, and kidneys were removed for histological examination. We found that bromobenzene induced significant nephrotoxicity reflected by an increase in levels of BUN and creatinine that was dose dependently prevented by the Cassia fistula fruit extract. The nephroprotective effect of the Cassia fistula fruit extract was confirmed by the histological examination of the kidneys. To the best of our knowledge, this is the first study to demonstrate the protective effect of Cassia fistula in nephrotoxicity.

Summative interaction between astaxanthin, Ginkgo biloba extract (EGb761) and vitamin C in suppression of respiratory inflammation: a comparison with ibuprofen.

In this study, combinations of Ginkgo biloba leaf extract (EGb761) plus the carotenoid antioxidant astaxanthin (ASX) and vitamin C were evaluated for a summative dose effect in the inhibition of asthma-associated inflammation in asthmatic guinea-pigs. Ovalbumin-sensitized Hartley guinea-pigs challenged with ovalbumin aerosol to induce asthma, were administered EGb761, ASX, vitamin C or ibuprofen. Following killing, bronchoalveolar lavage (BAL) fluid was evaluated for inflammatory cell infiltrates and lung tissue cyclic nucleotide content. Each parameter measured was significantly altered to a greater degree by drug combinations, than by each component acting independently. An optimal combination was identified that included astaxanthin (10 mg/kg), vitamin C (200 mg/kg) and EGb761 (10 mg/kg), resulting in counts of eosinophils and neutrophils each 1.6-fold lower; macrophages 1.8-fold lower, cAMP 1.4-fold higher; and cGMP 2.04-fold higher than levels in untreated, asthmatic animals (p < 0.05). In conclusion, EGb761, ASX and vitamin C are shown here to interact summatively to suppress inflammation with efficacy equal to or better than ibuprofen, a widely used non-steroidal antiinflammatory drug (NSAID). Such combinations of non-toxic phytochemicals constitute powerful tools for the prevention of onset of acute and chronic inflammatory disease if consumed regularly by healthy individuals; and may also augment the effectiveness of therapy for those with established illness.

Protective effect of Cassia fistula fruit extract against bromobenzene-induced liver injury in mice.

In the present study, hepatoprotective effect of Cassia fistula fruit extract was investigated in mice. Animals were divided into six groups receiving normal saline (1), bromobenzene (460 mg/kg) alone (2) and together with increasing doses (200, 400, 600, 800 mg/kg) of a crude hydro-alcoholic extract of Cassia fistula fruit (3-6, respectively). All administrations were carried out orally, daily, for 10 days. On the 11th day, animals were sacrificed. Serum activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (γGT) were determined; serum levels of direct and total bilirubin were measured; furthermore, livers were prepared for histological examination. Our results showed that bromobenzene treatment alone elicited a significant increase in activities of AST, ALT, ALP (but not γGT), and it significantly elevated the levels of direct and total bilirubin. Co-treatment with Cassia fistula fruit extract, however, significantly and dose-dependently decreased the above-mentioned enzyme activities (with exception of γGT) and bilirubin levels, producing a recovery to the naive state. The protective effect of Cassia fistula fruit extract against liver injury evoked by bromobenzene was confirmed by histological examination as well. In conclusion, the Cassia fistula fruit extract has significant hepatoprotective effect in our murine model.

Resveratrol: a multifunctional cytoprotective molecule.

Several recent studies have shown the protective effects of resveratrol in various experimental conditions and pathological animal models. Clinical studies also indicate the beneficial effects of resveratrol in different human diseases. Resveratrol produces a cascade against of events from the initial death-provoking signal, DNA fragmentation, and cell death. Researchers recognized the beneficial effect of resveratrol, as an important component, of the overall injury that occurs in various disorders such as oxidative stress, myocardial injury, anticancer activity, antidiabetic activity, and antihypercholesterolemic effects. Many mechanisms have been proposed for the initiation of protective effects of resveratrol in various pathological events, and considerable evidence exists to indicate that many mediators are involved in the resveratrol-induced protection. The present review focuses on the history, and the beneficial effects and mechanisms of resveratrol in oxidative stress, myocardial injury, anticancer-, antidiabetic- and antihypercholesterolemic activities, and discusses those therapeutic tools, which warrant becoming clinically important.

Isolation and analysis of bioactive constituents of sour cherry (Prunus cerasus) seed kernel: an emerging functional food.

A plant-based diet reduces the risk for the development of several chronic diseases, such as ischemic heart disease or cancer due to natural compounds found in plants. Numerous cereals, berries, fruits, and vegetables, including sour cherry (Prunus cerasus), which is a favored fruit worldwide, contain biological active components. The antioxidant components of the sour cherry seed kernel have not been investigated until now. The aim of our study was to isolate and analyze the bioactive constituents of sour cherry seed kernel. We separated the oil fraction of the kernel; then the remaining solid fraction was dried, and the oil-free kernel extract was further analyzed. Our results show that sour cherry seed kernel oil contains vegetable oils including unsaturated fatty acids, oleic acids, alpha-tocopherol, tocotrienols, and tocopherol-like components. The components of the solid fraction include various bioactive structures such as polyphenols, flavonoids, vegetable acids, and pro- and anthocyanidins, which could have useful therapeutic effects in the prevention of various vascular diseases.

Modulation of adenosine-induced responses in the guinea-pig trachea during long-term caffeine treatment: possible role of epithelium.

The responses to adenosine were studied on isolated, methacholine-precontracted tracheal strips of guinea pigs in the course of long-term caffeine or solvent treatment. Guinea pigs were fed caffeine for 10 weeks (average serum caffeine concentration: 39.1 +/- 3.9 microM). In epithelium-intact tracheal preparations (EITPs), sensititization to adenosine-induced relaxation (AIR) developed. It attained a maximum in week 1 of caffeine treatment, and then its level diminished and disappeared completely by weeks 4 - 6. In epithelium-denuded tracheal preparations (EDTPs), an increase in the sensitivity to adenosine was observed from week 1 to week 10 (a 4 - 6-fold reduction in EC50). Use of a coaxial bioassay system confirmed the role of epithelium in this process. The enhancement of the AIR of the EITPs was not modified by inhibitors of cyclooxygenase and lipoxygenase. Following depletion of the neuropeptides by acute capsaicin pretreatment, the AIR of the EITPs was strongly enhanced after caffeine treatment for 6 weeks. In chronically caffeine-treated EITPs, the inhibition of neutral endopeptidase led to dramatic reduction of the AIR. On the basis of the results by inhibiting nitric oxide synthase, it can be supposed that nitric oxide released from EITPs of long-lasting caffeine-treated animals operated as a constrictor agent. Our results show that chronic caffeine treatment gives rise to an initial sensitization to adenosine of the EITPs, this being followed by the development of a specific adaptive process in the epithelial cells, which counterbalances the increased tracheal sensitivity to adenosine.

Cardioprotective mechanisms of Prunus cerasus (sour cherry) seed extract against ischemia-reperfusion-induced damage in isolated rat hearts.

The effects of kernel extract obtained from sour cherry (Prunus cerasus) seed on the postischemic cardiac recovery were studied in isolated working rat hearts. Rats were treated with various daily doses of the extract for 14 days, and hearts were then isolated and subjected to 30 min of global ischemia followed by 120 min of reperfusion. The incidence of ventricular fibrillation (VF) and tachycardia (VT) fell from their control values of 92% and 100% to 50% (not significant) and 58% (not significant), 17% (P<0.05), and 25% (P<0.05) with the doses of 10 mg/kg and 30 mg/kg of the extract, respectively. Lower concentrations of the extract (1 and 5 mg/kg) failed to significantly reduce the incidence of VF and VT during reperfusion. Sour cherry seed kernel extract (10 and 30 mg/kg) significantly improved the postischemic recovery of cardiac function (coronary flow, aortic flow, and left ventricular developed pressure) during reperfusion. We have also demonstrated that the extract-induced protection in cardiac function significantly reflected in a reduction of infarct size. Immunohistochemistry indicates that a reduction in caspase-3 activity and apoptotic cells by the extract, beside other potential action mechanisms of proanthocyanidin, trans-resveratrol, and flavonoid components of the extract, could be responsible for the cardioprotection in ischemic-reperfused myocardium.