• The Korean Journal of Physiology and Pharmacology
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• 제14권1호
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• pp.21-28
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• 2010

Phenolic compounds affect intracellular free $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) signaling. The study examined whether the simple phenolic compound octyl gallate affects ATP-induced $Ca^{2+}$ signaling in PC12 cells using fura-2-based digital $Ca^{2+}$ imaging and whole-cell patch clamping. Treatment with ATP ($100\;{\mu}M$) for 90 s induced increases in $[Ca^{2+}]_i$ in PC12 cells. Pretreatment with octyl gallate (100 nM to $20\;{\mu}M$) for 10 min inhibited the ATP-induced $[Ca^{2+}]_i$ response in a concentration-dependent manner ($IC_{50}=2.84\;{\mu}M$). Treatment with octyl gallate ($3\;{\mu}M$) for 10 min significantly inhibited the ATP-induced response following the removal of extracellular $Ca^{2+}$ with nominally $Ca^{2+}$-free HEPES HBSS or depletion of intracellular $Ca^{2+}$ stores with thapsigargin ($1\;{\mu}M$). Treatment for 10 min with the L-type $Ca^{2+}$ channel antagonist nimodipine ($1\;{\mu}M$) significantly inhibited the ATP-induced $[Ca^{2+}]_i$ increase, and treatment with octyl gallate further inhibited the ATP-induced response. Treatment with octyl gallate significantly inhibited the $[Ca^{2+}]_i$ increase induced by 50 mM KCI. Pretreatment with protein kinase C inhibitors staurosporin (100 nM) and GF109203X (300 nM), or the tyrosine kinase inhibitor genistein ($50\;{\mu}M$) did not significantly affect the inhibitory effects of octyl gallate on the ATP-induced response. Treatment with octyl gallate markedly inhibited the ATP-induced currents. Therefore, we conclude that octyl gallate inhibits ATP-induced $[Ca^{2+}]_i$ increase in PC12 cells by inhibiting both non-selective P2X receptor-mediated influx of $Ca^{2+}$ from extracellular space and P2Y receptor-induced release of $Ca^{2+}$ from intracellular stores in protein kinase-independent manner. In addition, octyl gallate inhibits the ATP-induced $Ca^{2+}$ responses by inhibiting the secondary activation of voltage-gated $Ca^{2+}$ channels.

• International Journal of Oral Biology
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• 제45권4호
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• pp.218-224
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• 2020

The antitumor effects of octyl gallate (OG) were investigated on FaDu human hypopharyngeal squamous carcinoma cells. At various concentrations, OG inhibited the proliferation of FaDu cells by suppressing cell cycle regulators and induced apoptosis by activating caspase 3 and its downstream poly (ADP-ribose) polymerase, thereby damaging DNA. Immunoblotting demonstrated that OG significantly suppressed the expression of integrin family proteins (integrin α4, αv, β3, β4), hindering cell adhesion. The reduced expression of integrins subsequently mediated the mitogen-activated protein kinase signaling pathway to stimulate the activation of extracellular signal-regulated kinases and c-jun N-terminal kinases, leading to apoptosis. Thus, OG demonstrated antitumor activity on hypopharyngeal squamous carcinoma cells by suppressing cell proliferation and inducing apoptosis.

• 한국식품위생안전성학회지
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• 제12권3호
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• pp.210-216
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• 1997

The prevention of oxidative degradation in fats and oils is largely controlled by the use of synthetic phenolic antioxidants. Antioxidants, BHA: 2-&-3-tert-butyl-4-hydroxyanisol, BHT: 3,5-di-tert-butyl-4-hydroxytoluene, TBHQ: tert-butylhydroquinone, PG: propyl gallate, PTG: pentyl gallate, OG:octyl gallate, were extracted from fatty foods with hexane and from hexane layer to presaturated acetonitrile with hexane. The polar phenolic hydroxyl groups of antioxidants were silylated with MSTFA and injected to Gas Chromatography/Mass Spectrometry. The calibration plots were linear in the investigated range, 0.1~10.0 $\mu\textrm{g}$/g. The limit of detection for 6 phenolic antioxidants was 0.1 $\mu\textrm{g}$/g. Recoveries and reproducibilities from samples fortified at 1.0 $\mu\textrm{g}$/g were in the range of 70~90% and 0.5~13%, respectively. The simultaneous determination of phenolic antioxidants in fatty foods using GC/MS-SIM mode and macro program was described.

• 한국식품영양과학회지
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• 제45권7호
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• pp.1065-1070
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• 2016

본 연구는 리놀레인산에 7종의 산화방지제를 각각 0.02% 농도로 첨가하여 $50^{\circ}C$의 dry oven에서 8일간 자동산화 시키면서 이들 산화방지제의 잔존량 및 산화안정성을 측정하였다. 잔존량은 HPLC를 사용하여 측정하였으며, 산화안정성은 과산화물가를 이용하여 분석하였다. 잔존량은 0일째(100%)에서 시간에 따른 변화율을 측정하였고, 또한 잔존량을 이용하여 100-잔존량(%)으로 손실률(%)을 계산하였다. 산화방지제 손실률과 과산화물가의 상관관계를 분석하여 연관성을 확인하였다. 잔존량 분석 결과 tert-butylhydroquinone(TBHQ)> dodecyl gallate(DG)> octyl gallate(OG)> propyl gallate(PG)> butylated hydroxyanisole(BHA)> 2,4,5-trihydroxybutyrophenone(THBP)> butylated hydroxytoluene(BHT) 순으로 낮은 잔존량을 나타내었으나, BHA 같은 경우 다른 실험군에 비해 8일째의 잔존량이 4일째의 잔존량에 비하여 감소량이 크지 않았으며 TBHQ은 4일째의 잔존량이 이미 0에 가까운 값을 나타내어 8일째의 잔존량과 큰 차이가 없었다. 과산화물가 측정 결과 대조군> TBHQ> DG> OG> PG> BHA> THBP> BHT 순으로 높은 과산화물가를 보였으며 산화방지제 손실률과 과산화물가의 상관관계 분석 결과 상관관계(correlation coefficient, $R^2$)는 0.3913~0.9963의 범위로, 특히 BHT가 가장 높은 상관관계($R^2$=0.9963)를 보였다. BHA와 TBHQ를 제외한 대부분의 실험군에서 $R^2$ 값은 0.8769 이상의 높은 상관관계를 보였다. 본 연구에서 페놀계 산화방지제는 자동산화 과정에서 리놀레인산 기질 내 산화방지제의 잔존량과 기질의 산화안전성 간의 높은 상관관계를 보여주었다.