Kaempferol

Linearolactone (1) and kaempferol (2) have amebicidal activity in in vitro studies. The type of cell death induced by 1 and 2 and their effects on the virulence of E. histolytica were analyzed by transmission and confocal electron microscopy, reactive oxygen species (ROS) production, and apoptosis, detected by flow cytometry with dichlorofluorescein 2′,7′-diacetate and annexin-V binding, respectively, and confirmed by TUNEL. The interaction of 1 and 2 with actin was analyzed by docking, and the in vivo amoebicidal activity was established with the Mesocricetus auratus model; amebic liver abscess (ALA) development was evaluated by magnetic resonance (MR) and validated post mortem. In vitro, compounds 1 and 2 caused chromatin condensation, intracellular ROS, and loss of actin structures. Coupling analysis showed that they bind to the allosteric and catalytic sites of actin with binding energies of −11.30 and −8.45 kcal/mol, respectively. Treatments with 1 and 2 induced a decrease in ALA formation without toxic effects on the liver and kidney. Thus, compound 1, but not 2, was able to induce apoptosis-like effects in E. histolytica trophozoites by intracellular production of ROS that affected the actin cytoskeleton structuration. In vivo, compound 1 was more active than compound 2 to reduce the development of ALA. A mebiasis, caused by Entamoeba histolytica, is acquired after ingesting food or water contaminated with cysts, which excyst and give rise to trophozoites, which grow in the intestine. Once it is colonized, trophozoites invade the tissue and migrate to different organs, such as the liver. To date, the most commonly used treatment is metronidazole. However, studies have demonstrated the development of resistance to this drug, both in vitro and in vivo. 1 Therefore, there is a need to search for new, safer, and more effective antiamoebic drugs. Linearolactone (1) is a neo-clerodane diterpenoid isolated from Salvia polystachya, 2 and kaempferol (2) 3 is a flavonol isolated from Cuphea pinetorum, which have been characterized previously. Their antiprotozoal activities has been demonstrated in vitro, 2 where the half-maximal inhibitory concentrations (IC 50) of these compounds were established against Giardia lamblia and E. histolytica. Recently, it was reported that 2 inhibits the growth of E. histolytica by altering the functions of the cytoskeleton. 4 Based on these reports, 1 and 2 are considered good candidates to develop antiamoebic treatments. 3 However, the action mechanism of these specialized metabolites in animal models has not been described. In this work, we determined the type of death induced by 1 and 2 on E. histolytica trophozoites. The antiamoebic effect of both compounds on the development of amoebic liver abscess in a Mesocricetus auratus model was also analyzed, 5 and the potential toxic effects during the administration of the treatments were also examined.

A marked decrease in human cancers, including breast cancer, bone cancer, and cervical cancer, has been linked to the consumption of vegetable and fruit, and the corresponding chemoprotective effect has been associated with the presence of several active molecules, such as kaempferol. Kaempferol is a major flavonoid aglycone found in many natural products, such as beans, bee pollen, broccoli, cabbage, capers, cauliflower, chia seeds, chives, cumin, moringa leaves, endive, fennel, and garlic. Kaempferol displays several pharmacological properties, among them antimicrobial, anti-inflammatory, antioxidant, antitumor, cardioprotective, neuroprotective, and antidiabetic activities, and is being applied in cancer chemotherapy. Specifically, kaempferol-rich food has been linked to a decrease in the risk of developing some types of cancers, including skin, liver, and colon. The mechanisms of action include apoptosis, cell cycle arrest at the G2/M phase, downregulation of epithelial-mesenchy...

Context: Previous reports informed about the species-specific condition of plant phenolic profiles and the association between phenolic composition and plant antioxidant properties. The species-specific condition of phenolic patterns offers the opportunity to develop chemical quality markers for plants used in traditional medicine. However, changes in phenolic composition can occur during plant growth. Physalis angulata is an important medicinal plant for which the age-related variation of phenolic composition and antioxidant properties is unknown.

Aims: To assess the phenolic composition and antioxidant properties of above- and under-ground parts of P. angulata at four growth stages and evaluate their potential as chemical quality indicators.

Methods: A method of HPLC-DAD was used to assess the phenolic profiles. Anti-radical potential, total antioxidant capacity and iron reducing power were evaluated by spectrometric methods. Sample distinctiveness was determined by cluster analyses.

Results: The HPLC-DAD analysis revealed 21 phenolic compounds, which were accumulated in a tissue- and age-specific manner. On the contrary, a clear distinctiveness between phenolic contents and antioxidant properties of samples was not observed. Mature flowers highlighted for its total phenolic content (6.50 mg/g fresh tissue) and total antioxidant capacity (416.1 µg/mL). Young leaves were outstanding for its flavonoid content (37.86 µg/g fresh tissue) and reducing power (A700nm = 4.04). Immature calyces were worthy for its phenolic acid concentration (1.28 µg/g fresh tissue) and its free radical scavenging activity (EC50 = 0.12 mg/mL).

Conclusions: Phenolic profiles represent reliable chemical quality indicators for determining plant age, tissular origin, authenticity, and adulteration of herbal preparations of P. angulata.

A new and rapid HPLC method for identification and determination of myricetin, quercetin, kaempferol and total flavonoids in ten herbal drugs of Macedonian origin is presented. Preparation of samples (Uvae ursi folim, Pruni spinosae flos, Sambuci flos, Betulae folim, Primulae flos, Herniariae herba, Centaurii herba, Tiliae flos, Robiniae pseudoacaciae flos, Bursae pastoris herba) included hydrolysis of glycosides and extraction of total aglycones with ethyl acetate. HPLC analysis with UV-diode array detection was carried out on RP C18 column, using 5% acetic acid and acetonitrile in agradient elution mode and column temperature of 30 o C. The monitoring of the elution is performed in the whole UV-range and the acquisition of data for quantitative analysis at 367 nm. Screening of the extracts showed presence of quercetin in nine, kaempferol in seven and myricetin in only one sample. The quantitative analysis showed that the content of quercetin ranged from 0.026-0.506 % (m/m), while ...

We investigated the effects of kaempferol on porcine oocytes in vitro maturation. Kaempferol is one the most studied flavonoids and is in research attention on animal cells until 1979. Flavonoids are known as polyphenolic compounds synthesized by the plants. Cumulus-oocyte complexes aspirated from the ovaries were maturated in vitro, fertilized and embryos were cultured in a defined conditioned medium with 5, 15, 25, 35 µg/ml or without kaempferol supplementation. During in vitro maturation with highest kaempferol concentration (35 µg/ml) distinct significantly increase the rate of cumulus cell expansion in grad 4 (42.74 vs. 50.96%, p<0.01). The same, addition of 5 µg/ml kaempferol to the in vitro maturation medium increase significantly the rate of expansion compared to 25 µg/ml (42.20 vs. 48.67%, p<0.05) and increase distinct significantly the rate of expansion compared to 35 µg/ml (42.20 vs. 50.96%, p<0.01). Kaempferol supplementation (15 µg/ml vs. 35 µg/ml) of the in vi...

A marked decrease in human cancers, including breast cancer, bone cancer, and cervical cancer, has been linked to the consumption of vegetable and fruit, and the corresponding chemoprotective effect has been associated with the presence of several active molecules, such as kaempferol. Kaempferol is a major flavonoid aglycone found in many natural products, such as beans, bee pollen, broccoli, cabbage, capers, cauliflower, chia seeds, chives, cumin, moringa leaves, endive, fennel, and garlic. Kaempferol displays several pharmacological properties, among them antimicrobial, anti-inflammatory, antioxidant, antitumor, cardioprotective, neuroprotective, and antidiabetic activities, and is being applied in cancer chemotherapy. Specifically, kaempferol-rich food has been linked to a decrease in the risk of developing some types of cancers, including skin, liver, and colon. The mechanisms of action include apoptosis, cell cycle arrest at the G2/M phase, downregulation of epithelial-mesenchy...

A marked decrease in human cancers, including breast cancer, bone cancer, and cervical cancer, has been linked to the consumption of vegetable and fruit, and the corresponding chemoprotective effect has been associated with the presence of several active molecules, such as kaempferol. Kaempferol is a major flavonoid aglycone found in many natural products, such as beans, bee pollen, broccoli, cabbage, capers, cauliflower, chia seeds, chives, cumin, moringa leaves, endive, fennel, and garlic. Kaempferol displays several pharmacological properties, among them antimicrobial, anti-inflammatory, antioxidant, antitumor, cardioprotective, neuroprotective, and antidiabetic activities, and is being applied in cancer chemotherapy. Specifically, kaempferol-rich food has been linked to a decrease in the risk of developing some types of cancers, including skin, liver, and colon. The mechanisms of action include apoptosis, cell cycle arrest at the G2/M phase, downregulation of epithelial-mesenchy...

This article was originally published in a journal published by Elsevier, and the attached copy is provided by Elsevier for the author's benefit and for the benefit of the author's institution, for non-commercial research and educational use including without limitation use in instruction at your institution, sending it to specific colleagues that you know, and providing a copy to your institution's administrator. All other uses, reproduction and distribution, including without limitation commercial reprints, selling or licensing copies or access, or posting on open internet sites, your personal or institution's website or repository, are prohibited. For exceptions, permission may be sought for such use through Elsevier's permissions site at: http://www.elsevier.com/locate/permissionusematerial Abstract We examined the ability of the flavonoids quercetin and kaempferol to modulate inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and reactive C-protein (CRP) expression, and to induce changes in the nuclear factor kappa B (NF-κB) pathway in the human hepatocyte-derived cell line Chang Liver. Cells were incubated with a cytokine mixture supplemented with quercetin or kaempferol (5 to 200 μmol/l). Kaempferol produced a significant concentration-dependent decrease of iNOS, COX-2 and CRP protein level at all concentrations, but the percentage of inhibition induced by quercetin was reduced at high concentrations. Both flavonoids significantly inhibited mRNA level of iNOS, COX-2, and CRP. Inhibitory effects by quercetin and kaempferol were also observed on NF-κB activation and on protein concentration of the phosphorylated form of the inhibitor IκBα and of IKK (IκB kinase)α. The present study suggests that the modulation of iNOS, COX-2 and CRP by quercetin or kaempferol may contribute to the anti-inflammatory effects of these two structurally similar flavonoids in Chang Liver cells, via mechanisms likely to involve blockade of NF-κB activation and the resultant up-regulation of the pro-inflammatory genes. Our data also indicate that the minor structural differences between both compounds determine differences in their inhibitory capacity.