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The effect of resveratrol and its methylthio-derivatives on the Nrf2-ARE pathway in mouse epidermis and HaCaT keratinocytes

100%

Krajka-Kuzniak V., Szaefer H., Stefanski T., Sobiak S., Cichocki M., Baer-Dubowska W.

Cellular and Molecular Biology Letters

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2014

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tom 19

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nr 3

Resveratrol is the most extensively studied stilbene derivative. We previously showed that methylthiostilbenes were more effective inhibitors of CYP1A1 and 1B1 activity than resveratrol. In this study, we investigated whether resveratrol and its methylthio-substituted derivatives, i.e. 3-M-4′-MTS (S2), 3,5-DM-4′-MTS (S5) and 3,4,5-TM-4′-MTS (S7) could activate Nrf2 signaling in the mouse epidermis and in human keratinocytes. Western blot analysis showed translocation of Nrf2 from the cytosol to the nucleus in both models. All of the tested stilbenes increased GST activity, but resveratrol was the most effective inducer. Moreover, only resveratrol increased the protein level of GSTP in the mouse epidermis. GSTM was enhanced in HaCaT cells after the treatment with derivatives S2 and S5. The same effect was observed for GSTP in the case of compound S2. Resveratrol and its derivatives reduced the NQO2 protein level in HaCaT cells. Thus, it is possible that increased expression of GSTP or GSTM and GST activity was linked with NQO2 inhibition in these cells. The results of this study indicate that resveratrol and its methylthioderivatives activate Nrf2 not only in the mouse epidermis, but also in human keratinocytes. Upregulating GST isozymes might be particularly important for deactivating chemical carcinogens, such as PAH.

2

In vitro evaluation of the cytotoxic and anti-proliferative properties of resveratrol and several of its analogs

100%

Billack B., Radkar V., Adiabouah C.

Cellular and Molecular Biology Letters

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2008

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tom 13

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nr 4

553-569

Resveratrol (RES), a component of red wine, possesses anti-inflammatory properties. The studies described in the present work were aimed at evaluating the potential for RES and related stilbene analogs (piceatannol, PIC; pterostilbene, TPS; trans-stilbene, TS; and trans-stilbene oxide, TSO) to exhibit toxicity towards RAW 264.7 mouse macrophages. The effect of TS, TSO, RES and TPS on RAW 264.7 macrophage viability was determined by two standard methods: (a) the MTT assay and (b) the trypan blue dye exclusion test. Whereas macrophages were more sensitive to PIC (LC50 trypan ∼ 1.3 μM) and to TPS (LC50 trypan ∼ 4.0 μM and LC50 MTT ∼ 8.3 μM) than to RES (LC50 trypan ∼ 8.9 μM and LC50 MTT ∼ 29.0 μM), they were relatively resistant to TSO (LC50 trypan ∼ 61.0 μM and LC50 MTT > 100 μM) and to TS (LC50 trypan ≥ 5.0 μM and LC50 MTT ≥ 5.0 μM). The ability of selected stilbenes (RES, TPS and PIC) to exhibit growth inhibitory effects was also examined. Although RES and TPS were observed to inhibit cell proliferation in macrophages (IC50 ≤ 25 μM), these cells were resistant to growth inhibition by PIC (IC50 ≥ 50 μM). The data obtained in the present analysis demonstrate that substituted stilbene compounds such as RES have the capacity to exhibit cytotoxic and anti-proliferative activities in macrophages.

3

Influence of the multidrug transporter inhibitors on the activity of Kv1.3 voltage-gated potassium channels

100%

Teisseyre A., Duarte N., Ferreira M.-J. U., Michalak K.

Journal of Physiology and Pharmacology

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2009

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tom 60

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nr 1

69-76

Using the whole-cell patch-clamp technique, the influence of selected multidrug resistance modulators, both plant-derived compounds and derivatives on the activity of voltage-gated potassium channels Kv1.3 was investigated. Twelve compounds with phenolic and terpenic structures were tested: the stilbenes piceatannol (1) and its tetramethoxy (2) and tetracetoxy (3) derivatives, the flavonoids naringenin (4) and its methylated derivatives: naringenin-4',7-dimethylether (5) and naringenin-7-methylether (6), and aromadendrin (7), the coumarins esculetin (8) and scopoletin (9) and ent-abietane diterpenes, helioscopinolide B (10) and its 3ß-acetoxy derivative (11) and helioscopinolide E (12). The studies were performed on a model system with Kv1.3 channels endogenously expressed in human T lymphocytes. Obtained data provide evidence that compounds 2, 5 and 6 applied at 30 µM inhibited the amplitude of recorded currents to 31%, 4% and 29% of its control value, respectively. On the other hand, compounds 3, 4, 7-12 (at 30 µM) and compound 1 (at 40 µM) did not affect significantly the channel activity. These results indicate that some methoxy-derivatives of the tested compounds are effective inhibitors of Kv1.3 channels. Since the inhibition of Kv1.3 channels may inhibit the proliferation of prostate, breast and colon cancer cells expressing these channels, the channel inhibitors may exert an antiproliferative action. This action combined with a simultaneous modulation of the multidrug resistance may be significant for a potential application of these compounds in cancer chemotherapy.

4

Flavonoid glycosides in nine Polygonum L. taxons

100%

Smolarz H. D.

Acta Societatis Botanicorum Poloniae

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2002

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tom 71

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nr 1

5

Stilbene derivatives inhibit the activity of the inner mitochondrial membrane chloride channels

80%

Koszela-Piotrowska I., Choma K., Bednarczyk P., Dolowy K., Szewczyk A., Kunz W. S., Malekova L., Kominkova V., Ondrias K.

Cellular and Molecular Biology Letters

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2007

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tom 12

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nr 4

493-508

Ion channels selective for chloride ions are present in all biological membranes, where they regulate the cell volume or membrane potential. Various chloride channels from mitochondrial membranes have been described in recent years. The aim of our study was to characterize the effect of stilbene derivatives on single-chloride channel activity in the inner mitochondrial membrane. The measurements were performed after the reconstitution into a planar lipid bilayer of the inner mitochondrial membranes from rat skeletal muscle (SMM), rat brain (BM) and heart (HM) mitochondria. After incorporation in a symmetric 450/450 mM KCl solution (cis/trans), the chloride channels were recorded with a mean conductance of 155 ± 5 pS (rat skeletal muscle) and 120 ± 16 pS (rat brain). The conductances of the chloride channels from the rat heart mitochondria in 250/50 mM KCl (cis/trans) gradient solutions were within the 70–130 pS range. The chloride channels were inhibited by these two stilbene derivatives: 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS) and 4-acetamido-4′-isothiocyanostilbene-2,2′-disulfonic acid (SITS). The skeletal muscle mitochondrial chloride channel was blocked after the addition of 1 mM DIDS or SITS, whereas the brain mitochondrial channel was blocked by 300 μM DIDS or SITS. The chloride channel from the rat heart mitochondria was inhibited by 50–100 μM DIDS. The inhibitory effect of DIDS was irreversible. Our results confirm the presence of chloride channels sensitive to stilbene derivatives in the inner mitochondrial membrane from rat skeletal muscle, brain and heart cells.

6

Interaction of phenothiazines, stilbenes and flavonoids with multidrug resistance-associated transporters, P-glycoprotein and MRP1

80%

Wesolowska O.

Acta Biochimica Polonica

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2011

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tom 58

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nr 4

Multidrug resistance (MDR) of cancer cells poses a serious obstacle to successful chemotherapy. The overexpression of multispecific ATP-binding cassette transporters appears to be the main mechanism of MDR. A search for MDR-reversing agents able to sensitize resistant cells to chemotherapy is ongoing in the hope of their possible clinical use. Studies of MDR modulators, although they have not produced clinically beneficial effects yet, may greatly enrich our knowledge about MDR transporters, their specificity and mechanism of action, especially substrate and/or inhibitor recognition. In the present review, interactions of three groups of modulators: phenothiazines, flavonoids and stilbenes with both P-glycoprotein and MRP1 are discussed. Each group of compounds is likely to interact with the MDR transporters by a different mechanism. Phenothiazines probably interact with drug binding sites, but they also could indirectly affect the transporter's activity by perturbing lipid bilayers. Flavonoids mainly interact with ABC proteins within their nucleotide-binding domains, though the more hydrophobic flavonoids may bind to regions within transmembrane domains. The possible mechanism of MDR reversal by stilbenes may result from their direct interaction with the transporter (possibly within substrate recognition sites) but some indirect effects such as stilbene-induced changes in gene expression pattern and in apoptotic pathways should also be considered. Literature data as well as some of our recent results are discussed. Special emphasis is put on cases when the interactions of a given compound with both P-glycoprotein and MRP1 have been studied simultaneously.

7

Wplyw fitoestrogenow pokarmowych na organizm czlowieka. Cz.I. Wystepowanie fitoestrogenow w zywnosci oraz ich metabolizm

80%

Prescha A., Biernat J.

Bromatologia i Chemia Toksykologiczna

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2008

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tom 41

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nr 3

209-214

8

An ozone-responsive region of the grapevine stilbene synthase promoter differs from the basal pathogen-responsive sequence

80%

Ernst D., Grimmig B., Schubert R., Fischer R., Hain R., Sandermann H.

Biological Bulletin of Poznań. Supplement

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1997

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tom 34

Ograniczanie wyników

The effect of resveratrol and its methylthio-derivatives on the Nrf2-ARE pathway in mouse epidermis and HaCaT keratinocytes

In vitro evaluation of the cytotoxic and anti-proliferative properties of resveratrol and several of its analogs

Influence of the multidrug transporter inhibitors on the activity of Kv1.3 voltage-gated potassium channels

Flavonoid glycosides in nine Polygonum L. taxons

Stilbene derivatives inhibit the activity of the inner mitochondrial membrane chloride channels

Interaction of phenothiazines, stilbenes and flavonoids with multidrug resistance-associated transporters, P-glycoprotein and MRP1

Wplyw fitoestrogenow pokarmowych na organizm czlowieka. Cz.I. Wystepowanie fitoestrogenow w zywnosci oraz ich metabolizm

An ozone-responsive region of the grapevine stilbene synthase promoter differs from the basal pathogen-responsive sequence