Flavonoids beneficial effect

LDL when oxidized is recognized to play a crucial role in the development of atherosclerosis. It was thought that flavonoids could also protect LDL against oxidation, especially by limiting the degradation of vitamin E, the main antioxidant in LDL. Other beneficial effects of flavonoids have been reported inhibition of platelet... 

Cyanidin is the most common anthocyanin in foods. In addition, anthocyanins are stabilized by the formation of complexes with other flavonoids (co-pigmentation). In the United States, the daily anthocyanin consumption is estimated at about 200 mg. Several promising studies have reported that consumption of anthocyanin-rich foods is associated with reductions of the risks of cancers - and atherosclerosis and with preventive effects against age-related neuronal and behavioral declines. These beneficial effects of anthocyanins might be related to their reported biological actions such as modulators of immune response and as antioxidants. Knowledge of anthocyanin bioavailability and metabolism is thus essential to better understand their positive health effects. 

As in the case of tea flavonoids, there is controversy on the effect of milk proteins on the absorption and beneficial effects of cocoa flavonoids. Seraflni and others (2003)... 

Similarly to carotenoids, flavonoids also show considerable biological activity. Their beneficial effect in cancer and heart diseases has been proven many times [86-89], It has further been established that flavonoids improve cardiovascular remodelling and vascular function in NO-deficient hypertension [90], Moreover, flavonoid intake reduces the risk of chronic diseases [91], and beneficially influences inflammations [92], and ulcer formation [93,94],... 

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... 

Within the domain of medicinal plants, preparations of Ginkgo biloba (Ginkgoaceae) are the most widely sold phytomedicines, with sales of over US 1 billion in 1998. " These principally involve special extracts of the leaves. Flavonoids are, at least in part, responsible for the beneficial effects of Ginkgo extracts. Generally, enriched ginkgo extracts for the preparation of ginkgo products are standardized to contain 24% flavonoids and 6% terpene... 

In conclusion, different experimental studies have shown the ability of flavonoids to prevent ulcer formation in several experimental models, an effect that can be ascribed to several mechanisms of action, Fig. (1). It is probable that the activity at different levels, rather than at a single one, can better justify the beneficial effect of flavonids in these gastric conditions. 

Despite the lack of studies correlating the antidiarrheic activity of crude drugs with the presence of flavonoids, these have been also studied as pure compounds in this regard. The most used assay of antidiarrhoeic activity is the castor oil test, in which diarrhea is induced by the oral administration of castor oil to mice. Different flavonoids have been shown to possess antidiarrheal activity in this test quercetin, kaempferol, morin, myricetin, rutin (i.p.) [117,118], quercitrin (p.o.) [114,119], and tematin (i.p.) [44], all showing a dose-dependent activity in the range between 25 and 100 mg/kg. However, flavonoids are not only able to exert a preventive antidiarrheal effect in this acute model of experimentally-induced diarrhea, but also in chronic models. Thus quercitrin showed beneficial effects in a model of lactose-induced chronic diarrhea in rats, since it reduced the diarrheal output and facilitated colonic mucosal repair in lactose fed [120]. 

In conclusion, the beneficial effects of flavonoids in experimental IBD are mostly related with a preservation of intestinal function and/or with their ability to interfere simultaneously with different steps in the inflammatory cascade i.e. eicosanoid generation, oxygen and nitrogen reactive metabolites production and pro inflammatory cytokine release. The interest of flavonoids as potential drugs in the treatment of IBD is growing, and recently the intestinal antiinflammatory effects of the derivate flavonoid DA-6034 (7-carboxymethyloxy-3, 4, 5-trimethoxy flavone) has been reported in three... 

Similar to hydrophilic flavonoids, hydrophobic flavonoids can affect membrane permeability. Alterations in this biophysical property of liposome bilayers lead to the release of bulky molecules entrapped into the inner aqueous space. As mentioned in the previous section, a strong correlation was found between flavonoid retention to a hydrophobic matrix and their capacity to induce membrane leakage [Ollila et al., 2002]. Interestingly, hydrophilic flavonoids, such as (—)-epicatechin and related procyanidins (dimer to hex-amer) prevented Fe2 + -mediated liposome permeabilization, although in this case the beneficial effect could be related to both their antioxidant and metal chelating capacities and their membrane stabilizing properties [Verstraeten et al., 2004],... 

In addition to variations in citrus extracts, there are features of bioflavonoid effects on the mammalian body which may have contributed greatly to the controversy concerning flavonoid action. In 1940 Yosida (13) and in 1955 Rinehart (14) reported effects of hesperidin on rheumatic fever. Yosida determined the erythrocyte sedimentation rate (ESR) before and after injecting hesperidin into patients. In 26 sets of determinations the ESR was retarded in 19, unchanged in 3 and accelerated in 4 cases. Rinehart administered hesperidin to 26 patients, 22 showed a decreased ESR, 1 an unchanged and 3 an increased ESR. Hence, by the usual interpretation that an increased ESR indicates pathology, hesperidin in some cases showed beneficial effects, in others no effect and in still others made the disease worse. 

Bioflavonoids have been discovered to exert an antiadhesive action on blood cells. Erythrocyte adhesion is a general accompaniment of disease and trauma and has rheological implications. Hesperidin or other of the less active fiavonoids administered to a series of patients or added to blood in vitro may show three kinds of activity, inhibit blood cell adhesion in some, no effect in others or accelerate adhesion in still others, i.e., a trimodal action. This characteristic feature of flavonoid action undoubtedly has been interpreted as an inconsistent effect. However, all fiavonoids do not show a trimodal action. Also, there is considerable evidence linking rheological effects of bioflavonoids to their effects on capillary defects and beneficial effects in disease. Thus, the trimodal effects may explain the apparent inconsistent action against the above phenomena. 

Anila, L. and Vijayalakshmi, N.R., Beneficial effects of flavonoids from Sesamum indicum, Emblica officinalis, and Momordica charantia, Phytother. Res., 14, 592-595, 2000. 

Many medicinal plants contain chemical compounds called flavonoids. Some evidence suggests that flavonoids, also called bioflavonoids, can have beneficial effects on the body. Flavonoids may be able to help ward off bacteria and viruses and reduce inflammation. They may also be antioxidants, which are molecules that clear the body of harmful chemicals called oxygen free radicals. (Oxygen free radicals are highly reactive molecules that damage cells and have been associated with diseases such as cancer, diabetes, and cardiovascular disease.)... 

Compared with phenothiazines, much less is known about the effects exerted by different types of flavonoids on the properties of ionic channels. These compounds exert mostly beneficial effects on human health, acting mainly as nonspecific antioxidants that cause almost no side effects. Therefore, there was only a limited need to study specific interactions of flavonoids with different types of ionic channels. 

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