Effect of Herbal Teas on Conjugation Reactions in a Human Colon Carcinoma Cell Line, Caco-2

Okamura, Shingo; Tamura, Hiro Omi

doi:10.1248/jhs.50.189

Cited by 9 publications

(12 citation statements)

References 9 publications

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“…5,6) After supplementing Caco-2 cultures with 1-naphthol (200 mM), the accumulation of 1-naphthyl sulfate and glucuronide in the growth medium was determined by the analytical HPLC over a 24 h period. As shown in Fig.…”

Section: Effects Of Turmeric and Curcumin On Conjugation Reactions Inmentioning

confidence: 99%

“…Previously we have investigated such herb-drug interactions at the level of conjugation. 5,6) We have also recently established an assay system for conjugation reactions of 1-naphthol using a human adenocarcinoma cell line, Caco-2.7) In our current study, to elucidate the possible interaction of both turmeric and curcumin with the conjugation pathways in cells, which in many cases are involved in the activation of procarcinogens, we measured their effects on the conjugation activity of 1-naphthol in Caco-2 cells. …”

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Turmeric and Curcumin Modulate the Conjugation of 1-Naphthol in Caco-2 Cells

Naganuma

Saruwatari

Okamura

et al. 2006

Biological & Pharmaceutical Bulletin

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Turmeric is the powdered dry rhizome of the plant Curcuma longa and has been widely used as a coloring agent, as a spice and has been utilized in the treatment of inflammatory conditions and other diseases.1) Curcumin is a yellow pigment and is the major anti-oxidant and anti-inflammatory constituent of turmeric. It is present in curry and mustard, and it is used extensively in Asian countries and in traditional medicines. Curcumin and/or turmeric have both been shown to possess cancer chemopreventive activity in addition to anti-inflammatory activity, and these compounds have thus generated considerable attention as alternative medicines in recent years.2-4) The low incidence of colon cancer in Asian countries could be related to low meat intake, but may also be due to the regular use of turmeric in the diet of these regions. As the colon is exposed to turmeric and curcumin, it is a likely target for the anticarcinogenic activity of these compounds. Moreover, since these agents are often administered in combination with conventional therapeutic drugs, it is very important to further explore the potential benefits of herb-drug interactions. Previously we have investigated such herb-drug interactions at the level of conjugation. 5,6) We have also recently established an assay system for conjugation reactions of 1-naphthol using a human adenocarcinoma cell line, Caco-2.7) In our current study, to elucidate the possible interaction of both turmeric and curcumin with the conjugation pathways in cells, which in many cases are involved in the activation of procarcinogens, we measured their effects on the conjugation activity of 1-naphthol in Caco-2 cells. MATERIALS AND METHODS MaterialsPowdered turmeric was obtained from Wako, Ltd. and curcumin was purchased from Sigma. Water-soluble and DMSO-soluble turmeric solutions were prepared by stirring turmeric powder (10 g) in either 100 ml distilled water or DMSO for 3 h at room temperature. Each solution was then filtered.Cell Culture Human adenocarcinoma Caco-2 cells were grown in 12-well plates in 1 ml minimal essential medium (MEM) supplemented with 10% fetal bovine serum and additional non-essential amino acids. The cells were seeded at 5ϫ10 5 cells/ml and cultured for up to 3 weeks with medium changes every 4-5 d.Analyses of 1-Naphthyl Sulfates and Glucuronide 1-Naphthol (200 mM) was added to the culture medium and the cells were further incubated at 37°C. Aliquots of 50 ml of medium were removed at various times, and 30 ml of each of these samples was then filtered and injected into a HPLC apparatus, equipped with an ODS column (Chromolith Performance RP-18e, 100ϫ4.6 mm, Merck). The mobile phase consisted of 2 mM tetrabutylammonium hydrogen sulfate in water and acetonitrile (65 : 35). The flow rate was 1.0 ml/min with a column temperature of 40°C and elution was monitored at 285 nm. The retention times for 1-naphthol, 1-naphthyl sulfate and 1-naphthyl glucuronide were determined to be 19.0 min, 17.6 min and 4.6 min, respectively. The effects of curcumin or turmeric o...

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Section: Effects Of Turmeric and Curcumin On Conjugation Reactions Inmentioning

confidence: 99%

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Turmeric and Curcumin Modulate the Conjugation of 1-Naphthol in Caco-2 Cells

Naganuma

Saruwatari

Okamura

et al. 2006

Biological & Pharmaceutical Bulletin

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“…[13][14][15][16] If these events occurred in the placenta, they would likely interfere with normal fetal growth and development by disturbing the metabolism of nutrients or essential endogenous molecules such as hormones. Since coffee is consumed daily worldwide and several studies have reported that it has adverse effects on fetal growth and development, [9][10][11] we examined the effects of coffee on the conjugation of 1-naphthol in TR-TBT cells in our current study.…”

Section: Effects Of Coffee Upon the Conjugation Of 1-naphthol In Tr-tmentioning

confidence: 99%

“…17) Recent studies have demonstrated the induction or reduction of different isoforms of the UGT1A subfamily in Caco-2 cells by dietary flavonoids, such as chrysin and quercetin. 14,18,19) Coffee also contains several phenolic compounds with antioxidant properties and its total polyphenol content has been reported to range from 200 to 550 mg per standard serving. 20,21) To examine the possibility that the reduction of glucuronidation of 1-naphthol by coffee is due to its effects upon the Total RNA was isolated from TR-TBT 18d-1 cells treated with coffee for 24 hr and RT-PCR analysis of the UGT1A1, UGT1A6 and BCRP genes was then performed.…”

Section: Effects Of Coffee On the Expression Of Ugt And Bcrp Genesmentioning

confidence: 99%

Coffee Inhibits the Glucuronidation of 1-Naphthol in Rat Syncytiotrophoblast Cells

Ueno

Nakashima

Tamura

2008

JOURNAL OF HEALTH SCIENCE

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The placenta acts as a barrier that protects the fetus from xenobiotics in the maternal blood. Phase II conjugation reactions in the placenta are considered to play an important role in this protective process by transferring polar hydroxyl groups and thereby imparting water solubility that facilitates the excretion of xenobiotics. Since coffee consumption during pregnancy is reported to affect fetal growth and development, we examined its effects upon the conjugation reactions in the rat syncytiotrophoblast cell line TR-TBT 18d-1. We detected a high level of glucuronidation for 1-naphthol, a model compound, in both a dose-and culture time-dependent manner in the TR-TBT 18d-1 cells. However, no sulfation was detected in any of our analyses. Coffee was found to inhibit the glucuronidation of 1-naphthol with an IC 50 of 4.5 % (v/v). In contrast however, caffeine, which is a major bioactive constituent of coffee, did not show any inhibition at doses of up to 100 µM. Coffee was also found to inhibit UDP-glucuronosyl transferase (UGT) activity towards 1-naphthol in vitro to a similar extent [IC 50 = 1.5 % (v/v)] as in intact cells. Moreover, the expression of the UGT 1A6, which is known to mainly catalyze the glucuronidation of 1-naphthol, was not affected by coffee. If coffee inhibits placental glucuronidation during pregnancy, its consumption would increase the fetal plasma concentrations of harmful xenobiotics, potentially affecting normal fetal growth and development.

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Herbal teas

Sarwar¹,

Lockwood²

2010

Nutrafoods

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Effect of Herbal Teas on Conjugation Reactions in a Human Colon Carcinoma Cell Line, Caco-2

Cited by 9 publications

References 9 publications

Turmeric and Curcumin Modulate the Conjugation of 1-Naphthol in Caco-2 Cells

Turmeric and Curcumin Modulate the Conjugation of 1-Naphthol in Caco-2 Cells

Coffee Inhibits the Glucuronidation of 1-Naphthol in Rat Syncytiotrophoblast Cells

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