• Title/Summary/Keyword: $\alpha$-blocking

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Inhibitory Effects of β-Glycyrrhetinic Acid on Tumor Necrosis Factor-α Production in RAW 264.7 Cells

  • Park, Kyoung-Sik
    • Journal of Applied Biological Chemistry
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    • v.53 no.3
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    • pp.147-153
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    • 2010
  • $\beta$-glycyrrhetinic acid (GA), the active principle of licorice (Glycyrrhiza glabra L.) has been reported to exhibit anti-inflammatory properties in different animal models. In this study, the effects of GA on the production of inflammatory mediators including tumor necrosis factor (TNF)-$\alpha$, interleukin (IL)-6, nitric oxide (NO), and prostaglandin E (pGE)-2 were examined in RAW 264.7 cells in vitro. Furthermore, to elucidate a possible mechanism for the inhibitory effect of GA on the production of TNF-$\alpha$, it was investigated whether the treatment of GA affects the I-${\kappa}B{\alpha}$ degradation and subsequent nuclear translocation of NF-${\kappa}B$. Various inflammatory responses were induced in the culture system by treating with a lipopolysaccharide (LPS). GA showed anti-inflammatory activities in dose-dependant manner with $IC_{50}$ of $5.4{\mu}M$ by inhibiting the production of TNF-$\alpha$ in RAW 264.7 cells. In addition, the treatment of GA blocked both I-${\kappa}B{\alpha}$ degradation and the nuclear translocation of NF-${\kappa}B$ from cytosol to nucleus. However, it did not affect the production of IL-6, NO, and PGE-2, implying the direct blocking of the production of TNF-$\alpha$ resulting from both the I-${\kappa}B{\alpha}$ degradation and the nuclear translocation of NF-${\kappa}B$. This finding might provide the underlying mechanism to explain the reported anti-inflammatory activities of GA in animal models.

Effects of Oenanthe javanica on Transcriptional Regulation of COX-2 by Inhibiting Translocation of p65 Subunit in LPS-Stimulated Murine Peritoneal Macrophages

  • Lee, Jeong-Min;Kim, Hyun-Ji;Choi, Hee-Jung;You, Yang-Hee;Hwang, Kwon-Tack;Lee, Myung-Yul;Park, Chang-Soo;Jun, Woo-Jin
    • Food Science and Biotechnology
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    • v.15 no.6
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    • pp.975-979
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    • 2006
  • The extracts of Oenanthe javanica were evaluated for their effects on the expression of cyclooxygenase-2 (COX-2), which is mediated by the translocation of the p65 subunit into the nucleus. Fractions of ethyl acetate and chloroform from 80% ethanol extracts of O. javanica exhibited inhibitory effects on the secretion of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) from lipopolysaccharide (LPS)-stimulated peritoneal macrophages; however, the aqueous- and hexane-fractions showed no significant effect. The ethyl acetate- and chloroform-fractions also reduced the COX-2 enzyme levels after 24-hr treatment. RT-PCR showed that the mRNA levels of COX-2 decreased following treatment with these fractions, suggesting that COX-2 expression is transcriptionally regulated by these extracts. We examined the effects of the chloroform- and ethyl acetate-fractions on the cytosolic activation of nuclear factor-${\kappa}B$ ($NF-{\kappa}B$, p65 subunit) and on the degradation of inhibitor-${\kappa}B{\alpha}$ ($I-{\kappa}B{\alpha}$) in order to determine the mechanism of COX-2 regulation. The LPS-stimulated activation of the p65 subunit was significantly blocked upon the addition of $50\;{\mu}g/mL$ of these fractions, and the cytosolic $I-{\kappa}B{\alpha}$ degradation process was simultaneously inhibited. These findings suggest that the inhibition of COX-2 expression by the ethyl acetate-and chloroform-fractions may result from the inhibition of p65 translocation by blocking the degradation of $I-{\kappa}B{\alpha}$; this may be the mechanistic basis for the anti-inflammatory effects of O. javanica.

Inhibition of COX-2 Activity and Proinflammatory Cytokines($TNF-{\alpha}{\;}and{\;}IL-1{\beta}$) Production by Water-Soluble Sub-Fractionated Parts from Bee (Apis mellifera) Venom

  • Nam, Kung-Woo;Je, Kang-Hoon;Lee, Jang-Hurn;Han, Ho-Je;Lee, Hye-Jung;Kang, Sung-Kil;Mar, Woongchon
    • Archives of Pharmacal Research
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    • v.26 no.5
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    • pp.383-388
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    • 2003
  • Bee venom is used as a traditional medicine for treatment of arthritis. The anti-inflammatory activity of the n-hexane, ethyl acetate, and aqueous partitions from bee venom (Apis mellifera) was studied using cyclooxygenase (COX) activity and pro-inflammatory cytokines (TNF-$\alpha and IL-1\beta$) production, in vitro. COX-2 is involved in the production of prostaglandins that mediate pain and support the inflammatory process. The aqueous partition of bee venom showed strong dose-dependent inhibitory effects on COX-2 activity ($IC_{50} = 13.1 \mu$ g/mL), but did not inhibit COX-1 activity. The aqueous partition was subfractionated into three parts by molecular weight differences, namely, B-F1 (above 20 KDa), B-F2 (between 10 KDa and 20 KDa) and BF-3 (below 10 KDa). B-F2 and B-F3 strongly inhibited COX-2 activity and COX-2 mRNA expression in a dose-dependent manner, without revealing cytotoxic effects. TNF-$\alpha and IL-1\beta$ are potent pro-inflammatory cytokines and are early indicators of the inflammatory process. We also investigated the effects of three subfractions on TNF-$\alpha and IL-1\beta$ production using ELISA method. All three subfractions, B-F1, B-F2 and B-F3, inhibited TNF-$\alpha and IL-1\beta$production. These results suggest the pharmacological activities of bee venom on anti-inflammatory process include the inhibition of COX-2 expression and the blocking of pro-inflammatory cytokines (TNF-$\alpha and IL-1\beta$) production.

Bioequivalence and Pharmacokinetics of Carvedilol (25mg) Tablets in Volunteers (카베딜롤(25mg)정제의 생물학적 동등성 및 약물동태연구)

  • 우수경;김호순;강종성;권광일
    • YAKHAK HOEJI
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    • v.45 no.6
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    • pp.650-655
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    • 2001
  • Carvedilol is a nonselective $\beta$-blocking agent with vasodilating properties that are attributed mainly to its blocking activity at $\alpha$$^{1}$-receptors. Carvedilol is used in the treatment of mild to moderate hypertention and angina pectoris and is often used in combination with other drugs. This study was carried out to evaluate the bioequivalence and pharmacokinetics of two carvedilol 25mg tablet formulations according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty healthy volunteers are enrolled and received a single dose (25mg as carvedilol) of each drug in the fasting state, in a randomized 2-way crossover design. After oral administration, blond samples were collected for a period of 30 hours. Plasma concentrations of carvedilol were determined by a rapid and sensitive HPLC method with spectrofluorometric detection. The major pharmacokinetic parameters such as AU $C_{0-}$30hr/, AU $C_{inf}$ , $C_{max}$, $T_{max}$, $t_{1}$2 / Cl/F and V $_{\beta}$//F were calculated. ANOVA test and t-test were utilized for the statistical analysis of each parameter. The results showed that the differences in AU $C_{0-}$30hr/, $C_{max}$ and $T_{max}$ between two were ~5.66, 1.74 and 0.00%, respectively. Minimum detectable differences ($\Delta$) at $\alpha$=0.05 were less than$\pm$ 20% except $T_{max}$ (8.44, 18.36, and 33.86%, respectively). The 90% confidence intervals of all parameters were within $\pm$20% (-10.60~ -0.72, -9.00~12.49 and -19.81~19.81%, respectively). Therefore, it is concluded that the two formulations are bioequivalent for both the extent and the rate of absorption after single dose administration.ation.ion.ion.ation.ion.n.

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Involvement of α1B-adrenoceptors and Rho kinase in contractions of rat aorta and mouse spleen

  • Hadeel A. Alsufyani;James R. Docherty
    • The Korean Journal of Physiology and Pharmacology
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    • v.27 no.4
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    • pp.325-331
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    • 2023
  • α1-adrenoceptors link via the G-protein Gq/G11 to both Ca2+ entry and release from stores, but may also activate Rho kinase, which causes calcium sensitization. This study aimed to identify the subtype(s) of α1-adrenoceptor involved in Rho kinase-mediated responses in both rat aorta and mouse spleen, tissues in which contractions involve multiple subtypes of α1-adrenoceptor. Tissues were contracted with cumulative concentrations of noradrenaline (NA) in 0.5 log unit increments, before and in the presence of an antagonist or vehicle. Contractions produced by NA in rat aorta are entirely α1-adrenoceptor mediated as they are competitively blocked by prazosin. The α1A-adrenoceptor antagonist RS100329 had low potency in rat aorta. The α1D-adrenoceptor antagonist BMY7378 antagonized contractions in rat aorta in a biphasic manner: low concentrations blocking α1D-adrenoceptors and high concentrations blocking α1B-adrenoceptors. The Rho kinase inhibitor fasudil (10 µM) significantly reduced aortic contractions in terms of maximum response, suggesting inhibition of α1B-adrenoceptor mediated responses. In the mouse spleen, a tissue in which all 3 subtypes of α1-adrenoceptor are involved in contractions to NA, fasudil (3 µM) significantly reduced both early and late components to the NA contraction, the early component involving α1B- and α1D-adrenoceptors, and the late component involving α1B- and α1A-adrenoceptors. This suggests that fasudil inhibits α1B-adrenoceptor mediated responses. It is concluded that α1D- and α1B-adrenoceptors interact in rat aorta and α1D-, α1A- and α1B-adrenoceptors interact in the mouse spleen to produce contractions and these interactions suggest that one of the receptors preferentially activates Rho kinase, most likely the α1B-adrenoceptor.

NF-${\kappa}B$ Activation and cIAP Expression in Radiation-induced Cell Death of A549 Lung Cancer Cells (A549 폐암세포주의 방사선-유도성 세포사에서 NF-${\kappa}B$ 활성화 및 cIAP 발현)

  • Lee, Kye Young;Kwak, Shang-June
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.5
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    • pp.488-498
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    • 2003
  • Background : Activation of the transcription factor NF-${\kappa}B$ has been shown to protect cells from tumor necrosis factor-alpha, chemotherapy, and radiation-induced apoptosis. NF-${\kappa}B$-dependent cIAP expression is a major antiapoptotic mechanism for that. NF-${\kappa}B$ activation and cIAP expression in A549 lung cancer cells which is relatively resistant to radiation-induced cell death were investigated for the mechanism of radioresistance. Materials and methods : We used A549 lung cancer cells and Clinac 1800C linear accelerator for radiation. Cell viability test was done by MTT assay. NF-${\kappa}B$ activation was tested by luciferase reporter gene assay, Western blot for $I{\kappa}B{\alpha}$ degradation, and electromobility shift assay. For blocking ${\kappa}B$, MG132 and transfection of $I{\kappa}B{\alpha}$-superrepressor plasmid construct were used. cIAP expression was analyzed by RT-PCR and cIAP2 promoter activity was performed using luciferase assay system. Results : MTT assay showed that cytotoxicity even 48 hr after radiation in A549 cells were less than 20%. Luciferas assay demonstrated weak NF-${\kappa}B$ activation of $1.6{\pm}0.2$ fold compared to PMA-induced $3.4{\pm}0.9$ fold. Radiation-induced $I{\kappa}B{\alpha}$ degradation was observed in Western blot and NF-${\kappa}B$ DNA binding was confirmed by EMSA. However, blocking NF-${\kappa}B$ using MG132 and $I{\kappa}B{\alpha}$-superrepressor transfection did not show any sensitizing effect for radiation-induced cell death. The result of RT-PCR for cIAP1 & 2 expression was negative induction while TNF-${\alpha}$ showed strong expression for cIAP1 & 2. The cIAP2 promoter activity also did not show any change compared to positive control with TNF-${\alpha}$. Conclusion : We conclude that activation of NF-${\kappa}B$ does not determine the intrinsic radiosensitivity of cancer cells, at least for the cell lines tested in this study.

Autonomic and Frontal Electrocortical Responses That Differentiate Emotions elicited by the Affective Visual Stimulation

  • Sohn, Jin-Hun;Lee, Kyung-Hwa;Park, Mi-Kyung;Eunhey Jang;Estate Sokhadze
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2000.04a
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    • pp.15-25
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    • 2000
  • Cardiac, respiratory, electrodermal and frontal (F3, F4) EEG responses were analyzed and compared during to slides of International Affective Picture System (IAPS) in the study on 42 students. Physiological responses during 20s of exposure to slides intended to elicit happiness (nurturant and erotic), sadness, disgust, surprise, fear or anger emotions were quite similar and were expressed in heart rate (HR) deceleration, decreased HR variability (HRV), specific SCR, increased non-specific SCR frequency (N-SCR), and EEG changes exhibited in theta increase, alpha-blocking and increased beta activity, and frontal asymmetry. However, some emotions demonstrated variations of the response magnitudes, enabling to differentiate some paris of emotions by several physiological parameters. The profiles showed higher magnitudes of HRV and EEG responses in exciting (i.e., erotic) and higher cardiac and respiratory responses in surprise. The most different pairs were exciting-surprise (by HR, HRV, theta, and alpha asymmetry), exciting-sadness (by theta, alpha, and alpha asymmetry), and exciting-fear (by HRV, theta, F3 alpha, and alpha asymmetry). Nurturant happiness yielded the least differentiation. Differences were found as well within negative emotions, e.g., anger-sadness were differentiated by HRV and theta asymmetry, while disgust-fear by N-SCR and beta asymmetry. Obtained results suggest that magnitudes of profiles of physiological variables differentiate emotions evoked by affective pictures, despite that the patterns of most responses were featured by qualitative similarity in given passive viewing context.

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Anti-inflammatory Effects of Haedoksamultang in RAW 264.7 cells (해독사물탕(解毒四物湯)의 항염효과(抗炎效果) 및 면역반응(免疫反應)에 관(關)한 연구(硏究))

  • Kim, Yang-Ho;Cho, Han-Baek
    • The Journal of Korean Obstetrics and Gynecology
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    • v.21 no.2
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    • pp.166-183
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    • 2008
  • Purpose: This study was performed to determine anti-imflammatory effects of Haedoksamultang. Methods: In this study, I examined the effects of Haedoksamultang on the production of nitric oxide(NO), tumor necrosis factor-${\alpha}$(TNF-${\alpha}$), and interlukin-1${\beta}$(IL-1${\beta}$) as well as the expression of inducible NO synthase(iNOS), cyclooxygenase-2(COX-2), TNF-${\alpha}$, and IL-1${\beta}$ in RAW 264.7 cells. Haedoksamultang inhibited LPS-stimulated NO production. Western blotting and RT-PCR analysis showed that Haedoksamultang suppressed LPS-induced iNOS and COX-2 protein and mRNA expression in RAW 264.7 cells. Haedoksamultang also suppressed the expression and production of LPS-stimulated TNF-${\alpha}$ and IL-1${\beta}$ in RAW 264.7 cells. Haedoksamultang inhibited NF-${\kappa}B$ activation in LPS-treated RAW 264.7 cells. Moreover, this compound blocked $I{\kappa}B-{\alpha}$ phosphorylation and nuclear translocation of the cytosolic NF-${\kappa}B$ p65 subunit, which highly correlated with the production and expression of inflammatory mediators. Results: Haedoksamultang suppresses that inflammation-associated gene expression by blocking NF-${\kappa}B$ activation. Conclusion: These results suggest that Haedoksamultang may be beneficial for treating inflammatory disease.

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Effects of UK 14,304, An ${\alpha}_2$-Adrenergic Agonist, on Renal Function in Dog (${\alpha}_2$-아드레날린 효능약인 UK 14,304의 신장기능에 미치는 영향)

  • Ko, Suk-Tai;Kim, Hai-Suk;Choi, Hong-Seok
    • YAKHAK HOEJI
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    • v.41 no.4
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    • pp.498-511
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    • 1997
  • The effects of UK 14,304, an ${\alpha}_2$-adrenergic agonist, on renal function were investigated in dogs. UK 14,304, when given intravenousely($15.0{\mu}g/kg,\;50{\mu}g/kg$), produced the increase of urine flow accompanied with the marked augmentation of free water clearance ($C_{H_2O}$) and reabsorption rates of sodium in renal tubules ($R_{Na}$), and the remarkable decrease of osmolar clearance ($C_{osm}$) and the amounts of sodium excreted in urine ($E_{Na}$). UK 14,304 given into a renal artery($1.5{\mu}g/kg,\;5.0{\mu}g/kg$) elicited the increase of urine flow with the augmentation of $C_{H_2O}$ in both kidney. UK 14,304, when administered into carotid artery($3.0{\mu}g/kg,\;10.0{\mu}g/kg$). exhibited the same aspect as shown in intravenous UK 14.304 at smaller dose than the intravenous dose. Diuretic action of intravenous UK 14,304 were produced together with increase of $C_{H_2O}$ in situation of water diuresis too, changes of renal function in this state were the increase of $C_{osm},\;E_{Na},\;and\;E_K$ (excreted amounts of potassium in urine), and the decrease of $R_{Na}\;and\;R_K$, these were different appearances from situation of saline diuresis. Diuretic action of intravenous UK 14,304 were blocked completely by post or pretreatment of yohim-bine, ${\alpha}_2$-adrenergic blocking agents, and inhibited by pretreatment of vasopressin, antidiuretic hormone. Above results suggest that UK 14,304 produces the diuretic action by the inhibition of vasopressin secretion and suppression of electrolytes reabsorption of electrolytes in renal tubules mediated with central ${\alpha}_2$-adrenoceptor in dog.

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Influences of Adrenoreceptor Blockades on the Dose Response to Epinephrine (Epinephrine의 dose-response에 미치는 ${\alpha}-$${\beta}-receptor$ blocking agents의 영향(影響))

  • Cheon, Yun-Sook;Chun, Boe-Gwun;Shin, Man-Ryun
    • The Korean Journal of Pharmacology
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    • v.13 no.2
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    • pp.49-59
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    • 1977
  • Adrenergic receptors are now classified into alpha type and beta type These adrenergic receptors are distributed in various tissue in different patterns. Therefore, the adrenergic response of a certain tissue may be different from those of the other tissues, and such differences may exist among various species of animals. In this paper, the authors attempt to reevaluate the effect of epinephrine on the isolated atria, aortic strips, and vas deferenses of rabbits preincubated with alpha receptor blockades (ergotamine and dibenamine) and beta receptor blockades (propranolol and dichloroisoproterenol) in Locke-Ringer bathing medium. The results obtained were summarized as follows; 1) The dose dependent responses of isolated atria to epinephrine were significantly inhibited by propranolol and dichloroisoproterenol, and slightly inhibited by dibenamine, but not affected by ergotamine. 2) The dose dependent responses of excised aortic strips to epinephrine were significantly inhibited by ergotamine and dibenamine, but the responses were slightly potentiated by propranolol, and significantly by dichloroisoproterenol. 3) The dose dependent responses of isolated vas deferenses to epinephrine were significantly inhibited by ergotamine and dibenamine, but slightly potentiated by propranolol and dichloroisoproterenol.

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