• Archives of Pharmacal Research
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• v.26 no.9
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• pp.768-772
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• 2003

Tween 80 (Polysorbate 80) is a hydrophilic nonionic surfactant commonly used as an ingredient in dosing vehicles for pre-clinical in vivo studies (e.g., pharmacokinetic studies, etc.). Tween 80 increased apical to basolateral permeability of digoxin in Caco-2 cells suggesting that Tween 80 is an in vitro inhibitor of P-gp. The overall objective of the present study was to investigate whether an inhibition of P-gp by Tween 80 can potentially influence in vivo absorption of P-gp substrates by evaluating the effect of Tween 80 on the disposition of digoxin (a model P-gp substrate with minimum metabolism) after oral administration in rats. Rats were dosed orally with digoxin (0.2 mg/kg) formulated in ethanol (40％, v/v) and saline mixture with and without Tween 80 (1 or 10％, v/v). Digoxin oral AUC increased 30 and 61％ when dosed in 1 ％ and 10％ Tween 80, respectively, compared to control (P＜0.05). To further examine whether the increase in digoxin AUC after oral administration of Tween 80 is due, in part, to a systemic inhibition of digoxin excretion in addition to an inhibition of P-gp in the GI tract, a separate group of rats received digoxin intravenously (0.2 mg/kg) and Tween 80 (10％ v/v) orally. No significant changes in digoxin IV AUC was noted when Tween 80 was administered orally. In conclusion, Tween 80 significantly increased digoxin AUC and Cmax after oral administration, and the increased AUC is likely to be due to an inhibition of P-gp in the gut (i.e., improved absorption). Therefore, Tween 80 is likely to improve systemic exposure of P-gp substrates after oral administration. Comparing AUC after oral administration with and without Tween 80 may be a viable strategy in evaluating whether oral absorption of P-gp substrates is potentially limited by P-gp in the gut.

• Journal of Pharmaceutical Investigation
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• v.26 no.3
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• pp.175-185
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• 1996

To inhibit the enzymatic degradation of leucine enkephalin (Leu-Enk) and its synthetic analog. $[D-ala^2]$-leucine enkephalinamide (YAGFL), in the nasal, rectal and vaginal mucosal and serosal extracts of rabbits, effects of enzyme inhibitors such as amastatin (AM), puromycin (PM), thiorphan (TP), thimerosal (TM), EDTA, N-carboxymethyl-Phe-Leu (CPL), phenylethyl alcohol (PEA), phenylmercuric acetate (PMA), benzalkonium chloride (BC) and modified cyclodextrins, alone or in combination, were observed by assaying the pentapeptides staying intact during incubation. Mucosa extracts were prepared by exposing freshly-excised mucosal specimens mounted on Valia-Chien cells to isotonic phosphate buffer while stirring. The degradation of Leu-Enk and YAGFL followed the apparent first-order kinetics. The half-lives (mean) in the nasal, rectal and vaginal mucosal extracts were found to be 1.07, 0.33 and 1.14 hr for Leu-Enk, and 16.9, 6.2 and 6.8 hr for YAGFL, respectively. AM or PM, which is an aminopeptidase inhibitor, did not show a sufficient inhibition of Leu-Enk $(50\;{\mu}g/ml)$ degradation in all kinds of extracts. $Dimethyl-{\beta}-cyclodextrin\;(DM-{\beta}-CyD)$ decreased the degradation rate constants of Leu-Enk about 2 or 3 times, comparing with no additive. However, the use of mixed inhibitors of AM $(50\;{\mu}M)$/TM (0.25 mM)/EDTA (5 mM) resulted in a full stabilization of Leu-Enk by decreasing the degradation rate constants 67.3, 161.3 and 113.8 times far the nasal, rectal and vaginal mucosal extracts, respectively, comparing with no inhibitor. With mixed inhibitors, Leu-Enk remained intact more than 90% after 6 hr-incubation. In the stabilization of YAGFL, hM, TP or CPL alone showed little efffct, and some additives demonstrated a considerable inhibition of YAGFL degradation in the rank order of TM > BC > EDTA. However, the addition of mixed inhibitors such as TM (0.5 mM) and EDTA (5 mM) into the extracts protected YAGFL from the degradation by more than 85% even after 24 hr-incubation, suggesting almost complete inhibition of YAGFL degradation in the extract. On the other hand, $DM-{\beta}-CyD\;or\;hydroxypropyl-{\beta}-cyclodextrin$ (10%) were also found to retard enzymatic degradation rates of YAGFL markedly, and resulted in staying intact more than 80% of YAGFL in the nasal and vaginal mucosal extracts, and more than 60% in the rectal mucosal extract after 16 hr-incubation.

• Toxicological Research
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• v.32 no.3
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• pp.207-213
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• 2016

Although propolis is one of the most popular functional foods for human health, there have been no comprehensive studies of herb-drug interactions through cytochrome P450 (CYP) inhibition. The purpose of this study was to determine the inhibitory effects of propolis on the activities of CYP1A2, 2A6, 2B6, 2C9, 2C19, 2D6, 2E1 and 3A4 using pooled human liver microsomes (HLMs). Propolis inhibited CYP1A2, CYP2E1 and CYP2C19 with an $IC_{50}$ value of 6.9, 16.8, and $43.1{\mu}g/mL$, respectively, whereas CYP2A6, 2B6, 2C9, 2D6, and 3A4 were unaffected. Based on half-maximal inhibitory concentration shifts between microsomes incubated with and without nicotinamide adenine dinucleotide phosphate, propolis-induced CYP1A2, CYP2C19, and CYP2E1 inhibition was metabolism-independent. To evaluate the interaction potential between propolis and therapeutic drugs, the effects of propolis on metabolism of duloxetine, a serotonin-norepinephrine reuptake inhibitor, were determined in HLMs. CYP1A2 and CYP2D6 are involved in hydroxylation of duloxetine to 4-hydroxy duloxetine, the major metabolite, which was decreased following propolis addition in HLMs. These results raise the possibility of interactions between propolis and therapeutic drugs metabolized by CYP1A2.

• Culinary science and hospitality research
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• v.18 no.4
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• pp.233-242
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• 2012

Macrophage-derived nitric oxide (NO) plays an important role in immune responses. Overproduction of NO by inducible nitric synthase(iNOS) is known to be closely correlated with the pathology of a variety of diseases and inflammations. This study investigated the inhibitory effect of extract from various mushrooms(Phellinus linteus(PL), Inonotus obliquus(IO), Sarcodon aspratus(SA), Hericium erinacium(HE), and Russula cutefracta(RC)) on NO production and its molecular mechanism in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Among the mushrooms, HE extracts exhibited the strongest NO-inhibition activity. It was also found that HE extract inhibited LPS-induced iNOS and COX-2 expression in RAW264.7 cells. The present results give the understanding of biological activities of mushrooms and encourage their application for supplements and cook.

• Biomolecules & Therapeutics
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• v.18 no.2
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• pp.197-204
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• 2010

To establish the anti-inflammatory activity of the total flavonoid fraction of the root barks of Broussonetia papyrifera (EBP) and a new formula, the ethanol extract of the root barks of B. papyrifera was fractionated with ethylacetate, yielding the hydrophobic prenylated flavonoid-enriched fraction. EBP and the ethanol extract of the whole Lonicera japonica (ELJ) plant were then mixed at a ratio of 1:1 (w/w) to give a new preparation (BL) in the hope of obtaining an optimal formula with a higher anti-inflammatory activity. Evaluation of the effects of these preparations on A23187-treated rat basophilic leukemia (RBL-1) cells revealed that EBP potently inhibited 5-lipoxygenase (5-LOX), while ELJ showed weak inhibition. Additionally, the mixture (BL) clearly showed stronger inhibitory effects against 5-LOX than either preparation alone. These preparations also inhibited cyclooxygenase-2-catalyzed $PGE_2$ and inducible nitric oxide (NO) synthase-catalyzed NO production by lipopolysaccharide-treated RAW 264.7 cells. When tested against arachidonic acid-induced mouse ear edema, EBP showed strong inhibitory activity at doses of 5-200 mg/kg when administered orally, but BL had obviously stronger inhibitory effects. When tested against ${\lambda}$-carrageenan-induced paw edema in mice, BL showed a potent and synergistic anti-inflammatory effect. In addition, in the acetic acid-induced writhing test, BL was found to have strong analgesic activity at 50-400 mg/kg. Taken together, these results indicate that each of these preparations exert anti-inflammatory activity in vitro and in vivo. In particular, BL showed stronger anti-inflammatory activity than EBP, and these anti-inflammatory effects were partially related to the inhibition of eicosanoid and NO production. BL may be useful for the treatment of human inflammatory disorders.

• The Journal of Internal Korean Medicine
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• v.22 no.1
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• pp.79-85
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• 2001

Object : Hepatitis Treatment-tang No.1 has been used for the treatment of Liver disease and Jaundice. Long-term EtOH exposure leads to immunoregulatory and detoxification impairment. This study aimed to determine the relationship between TNF-${\alpha}$ production and expression, and EtOH-induced cytotoxicity on Hep G2 cells. Method : Cells were incubated with EtOH in the presence or absence of HT. The cells were tested after 24 hours and, again, after 48 hours. Cytoviability and TNF-${\alpha}$ release were analyzed by MTT assay and enzyme linked immunosorbent assay (ELISA), respectively. After 24 hours of EtOH exposure, the cytoviability decreased, and the release of TNF-${\alpha}$ was increased. Increased amounts of TNF-${\alpha}$ contribute to EtOH-induced cytotoxicity. The Anti-TNF-${\alpha}$ antibody almost abolished it. Interestingly, EtOH-induced cytotoxicity and TNF-${\alpha}$ production were inhibited by HT. Moreover, when HT was used in combination with the anti-TNF-${\alpha}$ antibody, there was a marked inhibition of EtOH-induced cytotoxicity. Results : These results suggest that HT may prevent the cytotoxicity through partial inhibition of the TNF-${\alpha}$ secretion.

• Journal of Acupuncture Research
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• v.22 no.2
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• pp.123-132
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• 2005

Melittin,cationic 26-amino acid, is the principal component of the bee venom (BV) which has been used for treatment of inflammatory disease such as arthritis rheumatism NF-kB is activated by subsequent release of inhibitory IkB via activation of a multisubunit IkB kinase (IKK). We previously found that melittin bind to the sulfhydryl group of p50, a subunit of NF-kB. Since sulfhydryl group is present in kinase domain of IKKa and IKKb, melittin could modify IKK activity by protein-protein interaction. We therefore examined effect of melittin on IKK activities in sodium nitroprusside (SNP)-stimulated synoviocyte obtained from RA patients. Melittin suppressed the SNP-induced release of IkB resulted in inhibition of DNA binding activity of NF-kB and NF-kB-dependent luciferase activity. Consistent with the inhibitory effect on NF-kB activation, IKKa and IKKb activities were also suppressed by melittin. Surface plasmon resonance analysis realized that melitin binds to IKKa $(Kd\;=\;1.34{\times}10-9M)$ and IKKb$(Kd\;=\;1.0{\times}10-9M)$. Inhibition of IKKa and IKKb resulted in reduction of the SNP-induced production of inflammatory mediators NO and PGE2 generation. The inhibitory effect of melittin on the IKKs activities, binding affinity of melittin to IKKs, and NO and PGE2 generation were blocked by addition of reducing agents dithiothreitol and glutathione. In addition, melittin did not show inhibitory effect in the transfected Synoviocytes with plasmid carrying dominant negative mutant IKKa (C178A) and IKKb (C179A). These results demonstrate that melittin directly binds to sulfhydryl group of IKKs resulting in IkBrelease, thereby inhibits activation of NF-kB and expression of genes involving in the inflammatory responses.

• Journal of Acupuncture Research
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• v.33 no.2
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• pp.1-9
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• 2016

Objectives : I investigated whether snake venom can synergistically strengthen the cytotoxic effects of NK-92 cells, and enhance the inhibition of the growth of lung cancer cells including NCI-H358 through the induction of death receptor dependent extrinsic apoptosis. Methods : Snake venom toxin inhibited cell growth of NCI-H358 Cells and exerted non influence on NK-92 cell viability. Moreover, when they were co-cultured with NK cells and concomitantly treated with $4{\mu}g/m{\ell}$ of snake venom toxin, more influence was exerted on the inhibition of growth of NCI-H358 cells than BV or NK cell co-culture alone. Results : The expression of Fas, TNFR2 and DR3 and in NCI-H358 lung cancer cells was significantly increased by co-culture of NK-92 cells and treatment of $4{\mu}g/m{\ell}$ of snake venom toxin, compared to co-culture of NK-92 cells alone. Coincidentally, Bax, caspase-3 and caspase-8 - expressions of pro-apoptotic proteins in the extrinsic apoptosis pathway, demonstrated significant increase. However, in anti-apoptotic NF-${\kappa}B$ activities, activity of the signal molecule was significantly decreased by co-culture of NK-92 cells and treatment of $4{\mu}g/m{\ell}$ of snake venom toxin, compared to co-culture of NK-92 cells or snake venom toxin treated by NCIH358 alone. Meanwhile, in terms of NO generation, there is a significant increase, in co-culture of NK-92 cells with NCI-H358 cells as well as the co-culture of NK-92 cells and concomitant treatment of $4{\mu}g/m{\ell}$ of snake venom toxin. However, no synergistic increase of NO generation was shown in co-culture of NK-92 cells and treatment of $4{\mu}g/m{\ell}$ of snake venom toxin, compared to co-culture of NK-92 cells with NCI-H358 cells. Conclusion : Consequently, this data provides that snake venom toxin could be useful candidate compounds to suppress lung cancer growth along with the cytotoxic effect of NK-92 cells through extrinsic apoptosis.

• Journal of Acupuncture Research
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• v.23 no.2
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• pp.113-123
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• 2006

Objectives : Deer antler Herbal-Acupuncture (DHA) solution represents one of the most commonly used medicine to treat rheumatoid arthritis. But, mechanisms of its antiarthritic activities are still poorly understood. Identification of common DHA aqua-acupuncture capable of affording protection or modulating the onset and severity of arthritis may have important human health implications. Results : We determined if DHA could prevent the binding of $IL-1{\beta}$ to its cellular receptors. DHA addition to rat chondrocytes treated with $IL-1{\beta}$ or with reactive oxygen species(ROS) prevents the activation of proteoglycan synthesis. After treatment with $IL-1{\beta}$, DHA increased the expression of mRNA encoding the type II $IL-1{\beta}$ receptor. These results emphasize the potential role of two regulating proteins of the $IL-1{\beta}$ signaling pathway that could account for the beneficial effect of DHA in osteRArthritis. The present study also identifies a novel mechanism of DHA-mediated anti-inflammatory activity. Conclusion : It is shown that DHA inhibits both $IL-1{\beta}-$ and $TNF-{\alpha}-induced$ NO production in normal human articular chondrocytes. The observed suppression of IL-1-induced NO production is associated with inhibition of inducible NO synthase(iNOS) mRNA and protein expression. In addition, DHA also suppresses the production of IL-1-induced cyclooxygenase-2 and IL-6. The constitutively expressed cyclooxygenase-1, however, was not affected by the sugar. These results demonstrate that DHA expresses a unique range of activities and identifies a novel mechanism for the inhibition of inflammatory processes.

• The Journal of Korean Medicine
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• v.23 no.4
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• pp.32-44
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• 2002

Objective: In this study, we investigated the effects of Rhizoma Cimicifugae (RC) on the induction of nitric oxide (NO) in RAW 264.7 murine macrophages treated with lipopolysaccharide (LPS). Methods: We examined whether RC have an antipyretic effect by inhibition of COX and/or NOS in fever that is evoked by an intraperitoneal injection of LPS in rats. Results: 1. RC inhibited NO metabolites produced by activated murine macrophage in a dose-dependent manner. 2. RC had an antipyretic effect in a dose-dependent manner in LPS-induced fever. 3. RC inhibited levels of both COX-2 protein and iNOS protein increased by the treatment of LPS in brain tissues as well as brain blood vessels. 4. There were no changes in proteins of nNOS/COX-1. Conclusions: RC has an antipyretic effect by attenuating the level of iNOS and COX-2 protein.