Coronary heart disease activity

NO-sensitive GC represents the most important effector enzyme for the signalling molecule NO, which is synthesised by NO synthases in a Ca2+-dependent manner. NO-sensitive GC contains a prosthetic heme group, acting as the acceptor site for NO. Formation of the NO-heme complex leads to a conformational change, resulting in an increase of up to 200-fold in catalytic activity of the enzyme [1]. The organic nitrates (see below) commonly used in the therapy of coronary heart disease exert their effects via the stimulation of this enzyme. 

Diabetic patients have reduced antioxidant defences and suffer from an increased risk of free radical-mediated diseases such as coronary heart disease. EC has a pronounced insulin-like effect on erythrocyte membrane-bound acetylcholinesterase in type II diabetic patients (Rizvi and Zaid, 2001). Tea polyphenols were shown to possess anti-diabetic activity and to be effective both in the prevention and treatment of diabetes (Choi et al, 1998 Yang et al, 1999). The main mechanism by which tea polyphenols appear to lower serum glucose levels is via the inhibition of the activity of the starch digesting enzyme, amylase. Tea inhibits both salivary and intestinal amylase, so that starch is broken down more slowly and the rise in serum glucose is thus reduced. In addition, tea may affect the intestinal absorption of glucose. 

ANDERSON J w, HANNA T J (1999) Whole grains and protection against coronary heart disease what are the active components and mechanisms , American Journal of Clinical Nutrition, 70, 307-8. 

Polyphenols and flavonoids present in red wine and grape juice, fruits and vegetables, have potent antioxidant activity, which may slow down oxidative modification of LDL, and their subsequent toxicity (Wedworth and Lynch, 1995). Phenolic compounds exert cytoprotection on vascular cultured cells by inhibiting the calcium rise and subsequent oxidized LDL-mediated cell death (Vieira et al, 1998). These compounds may play a role in the relatively low level of coronary heart disease in Prance ( Fnench Paradox ) and other Mediterranean countries (Renaud and Ruf, 1994). 

Because of human consumption of plant and plant products, there has been much interest on the impact of flavonoids on human health and this has been recently reviewed [149, 150 and ref therein]. Additionally, Passamonti et al. [151] have recently reviewed the issue of bioavailability of dietary flavonoids. Citrus flavonoids have been shown to have many beneficial effects on human health including anti-inflammatory activity, anticancer activity, antioxidant activity, and protection against coronary heart disease [reviewed in 152-154]. This has led to... 

Tea is another important dietary source for flavonoids, In fact, about half of the flavonoid intake in western populations is derived from black tea. Tea was the major source of flavonoids in the Dutch [6,13] and Welsh studies [17]. Only a small number of studies investigated the association between tea consumption and cardiovascular disease risk. No association between tea consumption and cardiovascular disease risk were reported in Scottish men and women [28] and in U.S. men in the Health Professionals follow-up study [29]. However, in a Norwegian population an inverse association was reported between tea intake, serum cholesterol, and mortality from coronary heart disease [30]. Several studies reported that tea consumption did not affect plasma antioxidant activity [31] and hemostatic factors [32]. However, a recent prospective study (the Rotterdam study) of 3,454 men and women 55 years and older followed for 2 to 3 years, showed a significant, inverse association of tea intake with severe (> 5 cm the length of the calcified area) aortic atherosclerosis. Odds ratios decreased approximately 70 % for drinking more than 500 mL/day (4 cups per day). The associations were stronger in women than in men. However, the risk reductions for moderate and mild atherosclerosis were only weak or absent [33]. 

Hypertension is an important risk factor for coronary heart disease and stroke. Since ancient times, hypertensive patients have been treated orally with plant extracts based on folk medicine. However, and despite their in vitro vasodilator effects, little information about the protective effects of flavonoids on hypertension is available in the literature. Flavonoids have been considered as active principles of several antihypertensive plant extracts (e.g. rhamnoglycoside of limocitrin isolated from Citrus limonum, kaempferol 4 -0-glucose and hyperin from Euphorbia maddeni, moracenins from Morus alba, procyanidin glycoside from Rhamnus lycioides) [150,151]. In all cases, only the acute antihypertensive effects after i.v. administration in anaesthetised normotensive and/or hypertensive animals have been described. In addition to the direct vasodilator effects discussed above, the inhibition of angiotensin-converting enzyme reported... 

The effects of wine and its polyphenol constituents on early indicators of coronary heart disease such as elevated levels of plasma lipids, platelets and serum antioxidant activity were discussed in a review by Cooper et al. (2004). This review also addressed whether the polyphenols or alcohol are responsible for the beneficial effects of wine on cardio-vascular health. The authors conclude that red wine polyphenols have little effect on plasma lipid concentrations, but that wine consumption reduces the susceptibility of low-density lipoprotein (LDL) cholesterol to oxidation and increase serum antioxidant capacity. These effects, however, do depend on the amount of wine that is consumed and the period of supplementation. It was suggested that specific polyphenols appear to have endothelium-dependent vaso-relaxing abilities. Red wine phenolics also have an inhibitory effect on platelet aggregation. Evidence suggests that alcohol has a positive synergistic effect with wine polyphenols on some atherosclerosis risk factors. Thus, evidence that wine drinking is beneficial for cardiac health appears positive. 

The effect of continuously administered low-dose 17-beta-estradiol (E2) + norethisterone acetate (NETA) on coagulation and fibrinolytic factors has been studied in 120 menopausal women, using two dosage variations (1 mg of E2 with 0.25 mg or 0.5 mg of NETA) compared with placebo over a year (53). In either dose, the combination significantly lowered plasma concentrations of factor VII, fibrinogen, antithrombin, and plasminogen activator inhibitor-1 (PAI-1) compared with placebo. These changes appear favorable, since they may lead to increased fibrinolytic activity and could reduce the risk of coronary heart disease. However, antithrombin activity was also reduced, which may increase the risk of venous thromboembolism. 

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