Effects of Nigella sativa seeds (black cumin) on insulin secretion and lipid profile: A pilot study in healthy volunteers.

It has been claimed that Nigella sativa seeds (NSS), also known as black cumin, have antidiabetic and lipid-lowering properties. Our pilot study investigated the effects of powdered NSS on insulin secretion and lipid profile in healthy male volunteers. We conducted a double-blind, randomized, placebo-controlled 4-week trial in 30 subjects, receiving NSS powder (1 g/day) or placebo orally (15 subjects/group). Insulin secretion as determined by the hyperglycaemic clamp technique, insulin sensitivity as well as cholesterol and triglycerides serum concentrations, were measured before and after treatment. NSS powder administration was clinically well tolerated. It did not modify fasting glycaemia and insulinaemia, and was ineffective on glucose-induced insulin secretion and insulin sensitivity. No significant changes on serum lipids were observed after treatment in any treatment groups, nor between the two treatment groups. However, in the treated group only, there was a significant correlation between total cholesterol change after treatment and its baseline level (r = -0.71, P = 0.006, n = 13), and between low-density lipoprotein (LDL) cholesterol change after treatment and its baseline level (r = -0.74, P = 0.004, n = 13). No such correlations were found for high-density lipoprotein (HDL) cholesterol, and for triglycerides. These results do not confirm any NSS effect on glucose regulation; however, they suggest that NSS powder may be of interest in lowering lipid concentrations in hyperlipidaemic subjects.

Psychological and physiological effects of bupropion compared to methylphenidate after prolonged administration in healthy volunteers (NCT00285155).

PURPOSE: Bupropion is largely used as an antidepressant and smoking cessation therapy. The aim of this work was to compare pharmacodynamic properties of bupropion and the amphetamine-like methylphenidate after sustained administration in humans. METHODS: Twelve male volunteers completed this randomized, double-blind, placebo controlled, cross-over study. Bupropion and methylphenidate were administered separately for initial half-dose 6-day periods (150 and 10 mg respectively) followed by full-dose 8-day periods (300 and 20 mg respectively). Outcomes were subjective feelings, cognitive performances, autonomic and physiological parameters. RESULTS: Data are expressed as mean(SEM). After repeated administration, bupropion, like methylphenidate, decreased asthenia-fatigue [44(3.2) and 42(3.7), respectively vs. 53(4.1) for placebo; p = 0.034], despite an impairment of sleep onset [-4.3(3.32) and -1.9(3.76), respectively vs. +7.5(3.69); p = 0.016]. Both drugs increased resting diastolic blood pressure [67.9(1.23) and 65.7(0.98), respectively vs. 62.5(1.42) mm Hg; p = 0.001], body temperature [36.5(0.12) and 36.5(0.14) vs. 36.3(0.10) °C; p = 0.037] and decreased body weight [-0.7(0.23) and -0.6(0.22), respectively vs. +0.2(0.27) kg; p = 0.038]. No significant change could be observed on cognitive functions, appetite and energy consumption. CONCLUSION: Although it may not share all the properties of stimulant drugs, the effect profile of bupropion presents a number of similarities with that of methylphenidate over a 2-week treatment period.

The IDEAL study : towards personalized drug treatment of hypertension.

OBJECTIVE: To identify markers (phenotypic, genetic, or environmental) of blood pressure (BP) response profiles to angiotensin converting enzyme inhibitors (ACEIs) and diuretics. METHODS: IDEAL was a crossover (two active and two wash out phases), double-blind, placebo-controlled trial. Eligible patients were untreated hypertensive, aged 25 to 70. After two visits, patients were randomized to one of four sequences. The main outcome was BP differences between the active treatment and placebo. RESULTS: One hundred and twenty-four patients were randomised: mean age 53, men 65%, family history of hypertension 60%. Average BP fall at each visit before randomisation was about 2% of the initial level reflecting both a regression to the mean and a placebo effect. CONCLUSION: The results are expected to improve knowledge in drug's mechanisms of action and pathophysiology of hypertension, and to help in personalizing treatment. The estimation of BP responses to each drug in standardized conditions provided a benefit to each participant.

Chronic istaroxime improves cardiac function and heart rate variability in cardiomyopathic hamsters.

PURPOSE: Istaroxime is a new luso-inotropic compound. It exerts inotropic action by reducing Na+/K+-ATPase activity, and simultaneously it stimulates sarcoplasmic reticulum Ca(2+)-ATPase function, thus also inducing lusitropic action. The aim of present study is to assess the effect of chronic istaroxime treatment on cardiac function and heart rate variability in Bio TO.2 Syrian hamster model of progressive heart failure. METHODS: Bio TO.2 hamsters were daily treated, from 12 to 28 weeks of age, with 30 mg/kg/day oral istaroxime. Age-matched Bio TO.2 and Bio F1B hamsters were treated with vehicle and used as diseased and healthy controls. At the end of treatment, hearts function and autonomic cardiac control were evaluated. RESULTS: Hearts from vehicle-treated Bio TO.2 when compared with hearts from Bio F1B showed higher heart/body weight ratio, and lower left ventricular systolic pressure (LVSP), positive and negative derivative of LV pressure (dP/dT), coronary flow rate (CFR). Hearts from istaroxime-treated when compared with those of vehicle-treated hamsters, showed the reduction of heart/body weight ratio, and the increase of LVSP, of both positive and negative dP/dT, and of CFR. Autonomic cardiac control, evaluated by HRV analysis, indicated in vehicle-treated Bio TO.2 hamsters, when compared to healthy, a shift towards increased sympathetic and decreased parasympathetic activities. Istaroxime-treatment preserved parasympathetic activity. CONCLUSIONS: Chronic istaroxime improves cardiac function and heart rate variability in Bio TO.2 Syrian hamster model of progressive heart failure.

Sympathomimetic inefficiency in restoring contractility in the acute or chronic beta-blocker-treated ischaemic heart: comparison with a new agent.

BACKGROUND: Adequate pharmacologic cardiac support in acute myocardial infarction (MI), as well as in chronic MI patients under beta-blocker therapy, is problematic due to the impaired cardiac response to beta-adrenergic agonists. New therapeutic approaches could resolve this problem. Istaroxime (ISTA) is a new Na(+),K(+)-ATPase inhibitor and SERCA(2) agonist. AIMS: To evaluate: 1) the effects of dobutamine (DOB) on left ventricular function in early (48-72 h) and late (14 days) phases of a post-MI canine model, compared to ISTA, and 2) the efficacy of DOB in chronic left ventricular dysfunction (6 months post-MI) in dogs pre-treated or not with a beta-blocker, compared with ISTA and milrinone (MIL). RESULTS: When compared to the effects in healthy animals, DOB increased contractility only slightly in the first 48-72 h post-MI, whereas its efficacy recovered partially by day 14 and fully by 6 months after MI. ISTA had a greater effect on contractility than DOB and improved relaxation, while DOB did not. Moreover, beta-adrenergic blockade inhibited the inotropic action of DOB, without altering the effect of ISTA. Surprisingly, beta-adrenergic blockade blunted the effects of MIL. CONCLUSION: ISTA may represent a novel strategy for enhancing left ventricular performance even in the context of acute MI and/or concomitant beta-adrenergic blockade.

Istaroxime: a new luso-inotropic agent for heart failure.

Istaroxime is a new luso-inotropic compound selected for the treatment of acute heart failure syndromes, which reduces sodium-potassium adenosine triphosphatase (ATPase) activity and stimulates the sarcoplasmic calcium ATPase isoform 2 reuptake function. The aim of this study was to evaluate the safety profile of istaroxime. For this purpose, istaroxime was administered during a 24-hour infusion to conscious dogs with chronic heart failure and to genetically cardiomyopathic BIO TO.2 hamsters for 34 weeks orally. The parameters recorded were arrhythmic events and hemodynamic effects in dogs and mortality in hamsters. In dogs, istaroxime at 1, 3, and 4 microg/kg per min did not trigger arrhythmic events or magnify preexisting events. It increased left ventricular (LV) dP/dtmax (about 50% at 3 microg/kg per min) and LV-dP/dtmax (about 20% at 3 microg/kg per min) without changing heart rate, blood pressure, or double product. At 4 microg/kg per min, istaroxime increased dP/dtmax>100% but induced intense emesis in all animals. In cardiomyopathic hamsters, the dose of 30 mg/kg prolonged the survival rate to 32%. In conclusion, istaroxime seems to be a promising and safe new drug for improving cardiac performance in the failing heart.

Hemodynamic effects of a new inotropic compound, PST-2744, in dogs with chronic ischemic heart failure.

Inotropic agents for acute decompensated heart failure are associated with a lack of efficacy or increased mortality. New compounds are needed to support patients with acute exacerbations of heart failure. This study examined the hemodynamic effects of a new inotropic agent (PST-2744) in dogs with chronic ischemic heart failure. Eight mongrel dogs at low risk for postmyocardial infarction (MI) sudden death entered the protocol. Dogs were studied after ischemic left ventricular dysfunction was induced by repeated injections of latex microspheres into the circumflex artery until the ejection fraction reached 35%. Hemodynamic parameters were measured at baseline and peak drug effect (PST-2744 5 microg.kg-1.min-1). In 5 animals, PST-2744 effects were compared with dobutamine. Heart rates, PR intervals and QT intervals were unchanged following PST-2744 administration. PST-2744 increased contractility (+dP/dt) by 56% from 1881 +/- 282 mm Hg/s to 2939 +/- 734 mm Hg/s (P < 0.01). The inotropic effect of PST-2744 was equal to that produced by 5-microg.kg-1.min-1 dobutamine (56% increase in +dP/dt), but peak heart rates were significantly higher with dobutamine (129 +/- 24 bpm PST-2744 versus 160 +/- 6 bpm 5-microg.kg-1.min-1 dobutamine, P < 0.002). No arrhythmias or conduction delays were seen with either compound. PST-2744 is an effective inotropic agent without positive chronotropic effect in subjects with stable moderate left ventricular dysfunction.