• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.19
• /
• pp.8007-8018
• /
• 2014

Cervical cancer is the most common gynecologic malignancy worldwide and development of new therapeutic strategies and anticancer agents is an urgent priority. Plants have remained an important source in the search for novel cytotoxic compounds and several polyphenolic flavonoids possess antitumor properties. In this review article, data about potential anticarcinogenic activity of common natural flavonoids on various human cervical cancer cell lines are compiled and analyzed showing perspectives for the use of these secondary metabolites in the treatment of cervical carcinoma as well as in the development of novel chemotherapeutic drugs. Such anticancer effects of flavonoids seem to differentially depend on the cellular type and origin of cervical carcinoma creating possibilities for specific targeting in the future. Besides the cytotoxic activity per se, several flavonoids can also contribute to the increase in efficacy of conventional therapies rendering tumor cells more sensitive to standard chemotherapeutics and irradiation. Although the current knowledge is still rather scarce and further studies are certainly needed, it is clear that natural flavonoids may have a great potential to benefit cervical cancer patients.

• Korean Journal of Pharmacognosy
• /
• v.28 no.1
• /
• pp.9-14
• /
• 1997

From the Evodiae Fructus, four flavonoids were isolated and identified as cacticin, limocitrin $3-0-{\beta}-D-galactoside$, hyperin and diosmin by means of chemical and spec-troscopic methods.

• Archives of Pharmacal Research
• /
• v.14 no.4
• /
• pp.357-358
• /
• 1991

Two flavonoids were isolated from the rhizomes of Belamcanda chinensis and identified as kanzakiflavove-2 and 2R:3R-dihydrokaempferol-7-methylether, respectively.

• Natural Product Sciences
• /
• v.10 no.1
• /
• pp.1-10
• /
• 2004

Plant flavonoids possess anti-inflammatory activity in vitro and in vivo. Although the action mechanisms are not fully understood, recent studies have clearly shown that certain flavonoids, especially flavone derivatives, express their anti-inflammatory activity at least in part by modulation of proinflammatory gene expression such as cyclooxygenase-2, inducible nitric oxide synthase and various cytokines. This review summarizes the recent findings of flavonoids modulating expression of proinflammatory molecules.

• Journal of fish pathology
• /
• v.28 no.1
• /
• pp.17-26
• /
• 2015

The purpose of this study is to explore the possibility of essential oils and flavonoids improving the performance of antibiotics, proving a higher efficacy in the presence of natural substances against Edwardsiella tarda and Streptococcus iniae. Increased efficacy was observed in several cases: both essential oils and flavonoids increased antibacterial efficacy of oxytetracycline and flumequine against E. tarda by 2-fold; essential oils and flavonoids increased antibacterial efficacy of nalidixic acid against E. tarda by 4-fold; flavonoids increased antibacterial efficacy of josamycin against S. iniae by 4-fold. The results obtained in this study suggest that essential oils and flavonoids might be especially useful in increasing the antimicrobial activity of nalidixic acid and josamycin against E. tarda and S. iniae in fish. Natural compounds examined in this study could also be useful to help decrease the overuse of antibiotics in fish.

• Natural Product Sciences
• /
• v.6 no.4
• /
• pp.170-178
• /
• 2000

Flavonoids are natural polyphenolic compounds widely distributed in plant kingdom. Although many flavonoids were found to show anti-inflammatory activity in vitro and in vivo, the potency of anti-inflammatory activity was not enough for a clinical trial. Thus, a search for finding potential flavonoid molecules is continuing. In this review, in vivo anti-inflammatory activity of various flavonoid derivatives is summarized mainly based on the results obtained in authors' laboratories. Among them, several biflavonoids such as amentoflavone and ginkgetin were found to possess anti-inflammatory activity on animal models of acute/chronic inflammation comparable to nonsteroidal and steroidal anti-inflammatory drugs currently used. In respect of their action mechanisms, the effects on arachidonic acid metabolism and nitric oxide production were described. Some flavonoids directly inhibit cyclooxygenase and/or lipoxygenase. Biflavones such as ochnaflavone and ginkgetin are inhibitors of phospholipase $A_2$. In recent studies, certain flavonoids were also found to suppress cyclooxygenase-2 and inducible nitric oxide synthase expression induced by inflammatory stimuli. Therefore, it is suggested that anti-inflammatory activity of the certain flavonoids (mainly flavones, flavonols and biflavonoids) may be mediated by direct inhibition of arachidonic acid metabolizing enzymes as well as suppression of the enzyme expression involved in inflammatory responses.

• Natural Product Sciences
• /
• v.10 no.1
• /
• pp.35-39
• /
• 2004

Aldose reductase (AR), the key enzyme of the polyol pathway, is known to play important roles in the diabetic complications. The inhibitors of AR, therefore, would be potential agents for the prevention of diabetic complications. In order to clarify the structural requirements of flavonoids for aldose reductase inhibitory activity, thirty flavonoids were examined. Among the thirty flavonoids, flavonols such as quercetin (5), reyneutrin (7), quercitrin (9), isoquercitrin (11), and avicularin (14) were found to exhibit much stronger AR inhibition. Lonicerin (10), amentoflavone (27) and sophoraflavanone B (30) were also showed strong inhibitory activity. Especially, quercitrin and reyneutrin exhibited the most inhibitory potency on rat lens (RL) AR. The results suggested that flavonol having the 7-hydroxyl and/or catechol moiety at the B ring exhibit strong activity. In addition, flavonols having 3-O-monosaccharide also showed stronger inhibition than free flavonols at the 3-position. These results suggested that quercitrin and reyneutrin are attributed to be the promising compounds for the prevention and/or treatment of diabetic complications.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.2
• /
• pp.427-436
• /
• 2012

Targeted therapy has been a very promising strategy of drug development research. Many molecular mechanims of diseases have been known to be regulated by abundance of proteins, such as receptors and hormones. Chemoprevention for treatment and prevention of diseases are continuously developed. Pre-clinical and clinical studies in chemoprevention field yielded many valuable data in preventing the onset of disease and suppressing the progress of their growth, making chemoprevention a challenging and a very rational strategy in future researches. Natural products being rich of flavonoids are those fruits belong to the genus citrus. Ethanolic extract of Citrus reticulata and Citrus aurantiifolia peels showed anticarcinogenic, antiproliferative, co-chemotherapeutic and estrogenic effects. Several examples of citrus flavonoids that are potential as chemotherapeutic agents are tangeretin, nobiletin, hesperetin, hesperidin, naringenin, and naringin. Those flavonoids have been shown to possess inhibition activity on certain cancer cells' growth through various mechanisms. Moreover, citrus flavonoids also perform promising effect in combination with several chemotherapeutic agents against the growth of cancer cells. Some mechanisms involved in those activities are through cell cycle modulation, antiangiogenic effect, and apoptosis induction.Previous studies showed that tangeretin suppressed the growth of T47D breast cancer cells by inhibiting ERK phosphorylation. While in combination with tamoxifen, doxorubicin, and 5-FU, respectively, it was proven to be synergist on several cancer cells. Hesperidin and naringenin increased cytotoxicitity of doxorubicin on MCF-7 cells and HeLa cells. Besides, citrus flavonoids also performed estrogenic effect in vivo. One example is hesperidin having the ability to decrease the concentration of serum and hepatic lipid and reduce osteoporosis of ovariectomized rats. Those studies showed the great potential of citrus fruits as natural product to be developed as not only the source of co-chemotherapeutic agents, but also phyto-estrogens. Therefore, further study needs to be conducted to explore the potential of citrus fruits in overcoming cancer.

• Korean Journal of Pharmacognosy
• /
• v.12 no.4
• /
• pp.203-207
• /
• 1981

The acute toxicity and sedative activity of flavonoids and saponin isolated from Zizyphus seeds have been evaluated in mice. All the compounds elicited potentiation of hexobarbital-induced hypnosis, inhibition of ladder-climbing and caffeine-induced hyperactivity. Swertisin was the most potent of all flavonoids tested. The potency of saponin in these tests was found to be higher than that of swertisin. The activities in rotarod test and electroshock seizure test, on the other hand, were relatively weak or nil. From these findings it was suggested that flavonoids and saponin from Zizyphus seeds have neuroleptic activity without anticonvulsant or muscle relaxant activity accompanied by neurological deficit.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.12
• /
• pp.4843-4847
• /
• 2015

To date, cytotoxic effects of flavonoids in various cancer cells are well accepted. However, the intracellular signaling cascades triggered by these natural compounds remain largely unknown and elusive. In this mini-review, the multiplicity of molecular targets of flavonoids in blood cancer cells is discussed by demonstrating the involvement of various signaling pathways in induction of apoptotic responses. Although these data reveal a great potential of flavonoids for the development of novel agents against different types of hematological malignancies, the pleiotropic nature of these compounds in modulation of cellular processes and their interactions certainly need unraveling and further investigation.