• Title/Summary/Keyword: modulatory action

Search Result 27, Processing Time 0.031 seconds

Repaglinide, but Not Nateglinide Administered Supraspinally and Spinally Exerts an Anti-Diabetic Action in D-Glucose Fed and Streptozotocin-Treated Mouse Models

  • Sim, Yun-Beom;Park, Soo-Hyun;Kang, Yu-Jung;Kim, Sung-Su;Kim, Chea-Ha;Kim, Su-Jin;Lim, Su-Min;Jung, Jun-Sub;Ryu, Ohk-Hyun;Choi, Moon-Gi;Suh, Hong-Won
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.17 no.6
    • /
    • pp.493-497
    • /
    • 2013
  • We have recently demonstrated that some anti-diabetic drugs such as biguanide and thizolidinediones administered centrally modulate the blood glucose level, suggesting that orally administered anti-diabetic drugs may modulate the blood glucose level by acting on central nervous system. The present study was designed to explore the possible action of another class of anti-diabetic drugs, glinidies, administered centrally on the blood glucose level in ICR mice. Mice were administered intracerebroventricularly (i.c.v.) or intrathecally (i.t.) with 5 to $30{\mu}g$ of repaglinide or nateglinide in D-glucose-fed and streptozotocin (STZ)-treated models. We found that i.c.v. or i.t. injection with repaglinide dose-dependently attenuated the blood glucose level in D-glucose-fed model, whereas i.c.v. or i.t. injection with nateglinide showed no modulatory action on the blood glucose level in D-glucose-fed model. Furthermore, the effect of repaglinide administered i.c.v. or i.t. on the blood glucose level in STZ-treated model was studied. We found that repaglinide administered i.c.v. slightly enhanced the blood glucose level in STZ-treated model. On the other hand, i.t. injection with repaglinide attenuated the blood glucose level in STZ-treated model. The plasma insulin level was enhanced by repaglinide in D-glucose-fed model, but repaglinide did not affect the plasma insulin level in STZ-treated model. In addition, nateglinide did not alter the plasma insulin level in both D-glucose-fed and STZ-treated models. These results suggest that the anti-diabetic action of repaglinide appears to be, at least, mediated via the brain and the spinal cord as revealed in both D-glucose fed and STZ-treated models.

Modulation of Bujaijung-tang and Bojungikgi-tang on Inhibitory and Excitatory Neurotransmitters Activated Ion Channels (부자이중탕과 보중익기탕의 억제성 및 흥분성 신경전달 물질에 의하여 활성화되는 이온통로 조절작용)

  • Lee, Hye-Jung;Seo, Jung-Chul;Lee, Jae-Dong;Kim, Ee-Hwa;Lee, Choong-Yeol;Chung, Joo-Ho;Shin, Min-Chul;Kim, Hyun-Bae;Kim, Youn-Jung;Kim, Chang-Ju
    • Journal of Acupuncture Research
    • /
    • v.17 no.4
    • /
    • pp.5-17
    • /
    • 2000
  • To research the characteristics of ion currents induced by Bujaijung-tang and Bojungikgi-tang, nystatin-perforated patch clamp technique under voltage-c(amp condition was used. Periaqueductal gray neuron was dissociated from Sprauge-Dawley rat, 10-15 days old. Cytotoxicity of Bujaijung-tang and Bojungikgi-tang showed incubation time and concentration dependent manner. Ion current activated by Bujaijung-tang and Bojungikgi-tang were inhibited by bicuculline and strychnine and CNQX. It can be suggested that Bujaijung-tang and Bojungikgi-tang modulate inhibitory and excitatory neurotransmitters-, GABA, glycine and non-NMDA, acticvated ion channels. Modulatory effect of Bujaijung-tang and Bojungikgi-tang was more greater in inhibitory neurotransmitters. Low concentration of Bujaijung-tang which dose not elicit ion current itself, activated GABA and glycine induced chloride currents. In this study, we can found that the activation of Bujaijung-tang and Bojungikgi-tang on non-NMDA subtypes of glutamate receptor is its major action mechanism and can be used as very effective Herb treatment on Myasthenia gravis patient.

  • PDF

Sulfatase 1 mediates the inhibitory effect of angiotensin II type 2 receptor inhibitor on angiotensin II-induced hypertensive mediator expression and proliferation in vascular smooth muscle cells from spontaneously hypertensive rats

  • Kim, Hye Young;Cha, Hye Ju;Kim, Hee Sun
    • Journal of Yeungnam Medical Science
    • /
    • v.34 no.1
    • /
    • pp.43-54
    • /
    • 2017
  • Background: Extracellular sulfatases (Sulfs), sulfatase 1 (Sulf1) and sulfatase 2 (Sulf2), play a pivotal role in cell signaling by remodeling the 6-O-sulfation of heparan sulfate proteoglycans on the cell surface. The present study examined the effects of Sulfs on angiotensin II (Ang II)-induced hypertensive mediator expression and vascular smooth muscle cells (VSMCs) proliferation in spontaneously hypertensive rats (SHR). Methods: Ang II receptors, 12-lipoxygenase (12-LO), and endothelin-1 (ET-1) messenger RNA (mRNA) expressions in SHR VSMCs were analyzed by real-time polymerase chain reaction and Western blotting. VSMCs proliferation was determined by [$^3H$]-thymidine incorporation. Results: Basal Sulfs mRNAs expression and enzyme activity were elevated in SHR VSMCs. However, Sulfs had no effect on the basal or Ang II-induced 12-LO and ET-1 mRNA expression in SHR VSMCs. The inhibition of Ang II-induced 12-LO and ET-1 expression by blockade of the Ang II type 2 receptor ($AT_2\;R$) pathway was not observed in Sulf1 siRNA-transfected SHR VSMCs. However, Sulf2 did not affect the action of $AT_2\;R$ inhibitor on Ang II-induced 12-LO and ET-1 expression in SHR VSMCs. The down-regulation of Sulf1 induced a reduction of $AT_2\;R$ mRNA expression in SHR VSMCs. In addition, the inhibition of Ang II-induced VSMCs proliferation by blockade of the $AT_2\;R$ pathway was mediated by Sulf1 in SHR VSMCs. Conclusion: These findings suggest that extracellular sulfatase Sulf1 plays a modulatory role in the $AT_2\;R$ pathway that leads to an Ang II-induced hypertensive effects in SHR VSMCs.

Analysis of the characteristics of mouthguards that affect isokinetic muscular ability and anaerobic power

  • Jung, Jae-Kwang;Chae, Woen-Sik;Lee, Kyu-Bok
    • The Journal of Advanced Prosthodontics
    • /
    • v.5 no.4
    • /
    • pp.388-395
    • /
    • 2013
  • PURPOSE. The purpose of this study was to estimate the effects of occlusal stability to identify action mechanisms of mouthguards, known to have a modulatory effect on limb muscle function. MATERIALS AND METHODS. This study included 20 male subjects to perform the isokinetic muscle tests and the Wingate anaerobic power test on both knee joints under five closed-mouth conditions: without or with 4 types of mouthguards with thickness of 2 mm based on premolar area: (1) full-coverage, (2) anterior partial-coverage, (3) right posterior partial-coverage, and (4) left posterior partial-coverage. The obtained results were subjected to One-way ANOVA with repeated measures, followed by post hoc test of the contrast method (${\alpha}$=.05). RESULTS. There was no significant difference between the closed position with and without a full-coverage mouthguard in all variables. However, significant differences were observed between with and without a partial-coverage mouthguard in muscular endurance during extension of the left knee, muscular power and endurance during flexion of the right knee. Additionally, significant differences were found between occlusal states with full- and partial-coverage mouthguards in muscular power and endurance during extension of the left knee. CONCLUSION. These findings indicate the elevation of vertical dimension by 2 mm or the inducement of occlusal stability had little effect on isokinetic muscle strength and anaerobic performance, while uneven distribution of occlusal force might have some positive effects.

The Effects of Gokgisaeng on Anti-inflammation and Rat C6 Glioma Cell Migration (곡기생(槲寄生)의 항염증 효능 및 암세포 이주저해에 미치는 영향)

  • Kim, Hyun-Young;Jang, Soo-Young;Jeong, Ji-Cheon;Shin, Hyeon-Cheol
    • The Journal of Internal Korean Medicine
    • /
    • v.34 no.1
    • /
    • pp.31-45
    • /
    • 2013
  • Objectives : Gokgisaeng (Korean mistletoe) is used for the treatment of inflammatory and cancer diseases in traditional Korean medicine and its major component lectins have been reported to induce nitric oxide (NO) in RAW 264.7 macrophages, and also induce apoptosis of various types of cancer cells, although its modulatory effects on cancer cell migration and macrophage activation is poorly understood. The aim of this study is to clarify molecular mechanisms of action responsible for the anti-inflammatory and antitumor migration potentials of Korean mistletoe extract (KME). Methods : We investigated the anti-inflammatory activity of KME on NO production and inducible nitric oxide synthase (iNOS) expression by lipopolysaccharide (LPS) in both RAW 264.7 macrophages and rat C6 glioma cells, and also evaluated inhibitory efficacy on glioma cell growth and migration. For assessment, XTT assay, nitrite assay, RT-PCR, scratch-wound and Boyden chamber assay, and western blot analysis were performed. Results : Previously reported, unlike the efficacy of Gokgisaeng lectin, KME inhibited NO production and iNOS expression, and suppressed pro-inflammatory mediators including IL-$1{\beta}$, IL-6, COX-2, iNOS in LPS-stimulated RAW 264.7 cells. Furthermore, KME suppressed tumor cell growth and migration, and it also inhibited LPS-induced NO release and iNOS activation by down-regulating expression of protein kinase C (PKC) and phosphorylation of ERK in C6 glioma cells. Conclusions : Our research findings provide evidence that KME can play a significant role in blocking pro-inflammatory reaction and malignant progression of tumors through the suppression of NO/iNOS by down-regulating of inflammatory signaling pathways, PKC/ERK.

Potentiation of Morphine's Antinociception by Group II and Group III Metabotropic Glutamate Receptors Agonists on a Rat Incisional Pain

  • Kim, Chang Mo;Choi, Jeong Il;Bae, Hong Beom;Kim, Seok Jai;Chung, Sung Tae;Kim, Ok Hwan;Yoon, Myung Ha
    • The Korean Journal of Pain
    • /
    • v.19 no.2
    • /
    • pp.131-136
    • /
    • 2006
  • Background: The aim of this study was to clarify the role of spinal groups II and III metabotropic glutamate receptors (mGluRs) with respect to postoperative pain at the spinal level. In addition, the nature of the pharmacological interaction between groups II and III mGluRs agonists and morphine was determined. Methods: Catheters were inserted into the intrathecal space of male SD rats. To induce postoperative pain, an incision was made in the plantar surface of the hind paw. A pharmacological characteristic for the interaction between groups II and III mGluRs agonists and morphine was evaluated using a fixed-dose analysis. Results: None of intrathecal group II and III mGluRs agonists modified the withdrawal threshold of the incisional pain. The administration of intrathecal morphine resulted in an increase of a dose dependent withdrawal threshold. A fixed-dose analysis revealed that the group III mGluRs agonist, ACPT-III, increased the antinociceptive action of morphine, while the group II mGluRs agonist, APDC, had no effect the antinociception of morphine. Conclusions: These results suggest that group II and III mGluRs may not play a direct modulatory role in the processing of postoperative pain at the spinal level. However, agonizing group III mGluRs may indirectly contributable to the potentiation of morphines antinociception in the spinal cord. Thus, the combination of morphine and a group III mGluRs agonist may be useful in the management of spinal postoperative pain.

Anti-obese related pharmacological effects of standard potato protein extracts on the 45%Kcal high fat diet supplied mice

  • Kang, Su-Jin;Song, Chang-Hyun;Kim, Jong-Kyu;Chun, Yoon-Seok;Han, Chang-Hyun;Lee, Young-Joon;Ku, Sae-Kwang
    • Journal of Society of Preventive Korean Medicine
    • /
    • v.22 no.2
    • /
    • pp.77-107
    • /
    • 2018
  • Objectives : In present study, therefore, possible beneficial pharmacological activities of standard potato protein extracts (SPE) were observed on the mild diabetic obese mice. Methods : After end of 12 weeks of continuous oral administrations of three different dosages of SPE 400, 200 and 100 mg/kg, or metformin 250 mg/kg, analyzed the hepatoprotective, hypolipidemic, hypoglycemic, nephroprotective and anti-obesity effects, separately. In addition, liver antioxidant defense systems were additionally measured with lipid metabolism-related genes expressions and hepatic glucose-regulating enzyme activities for action mechanism. Results : All of diabetes and related complications including obesity were significantly inhibited by treatment of SPE 400, 200 and 100 mg/kg, dose-dependently, and they also dramatically normalized the hepatic lipid peroxidation and depletion of liver endogenous antioxidant defense system, the changes of the hepatic glucose-regulating enzyme activities, also changes of the lipid metabolism-related genes expressions including hepatic $AMPK{\alpha}1$ and $AMPK{\alpha}2$ mRNA expressions, dose-dependently. Especially, SPE 200 mg/kg constantly showed favorable inhibitory activities against type II diabetes and related complications as comparable to those of metformin 250 mg/kg in HFD mice, respectively. Conclusions : The present work demonstrated that SPE 400, 200 and 100 mg/kg showed favorable anti-diabetic and related complications including obesity refinement activities in HFD mice, through AMPK upregulation mediated hepatic glucose enzyme activity and lipid metabolism-related genes expression, antioxidant defense system and pancreatic lipid digestion enzyme modulatory activities.

Thiol-dependent Redox Mechanisms in the Modification of ATP-Sensitive Potassium Channels in Rabbit Ventricular Myocytes

  • Han, Jin;Kim, Na-Ri;Cuong, Dang-Van;Kim, Chung-Hui;Kim, Eui-Yong
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.7 no.1
    • /
    • pp.15-23
    • /
    • 2003
  • Cellular redox state is known to be perturbed during ischemia and that $Ca^{2+}$ and $K^2$ channels have been shown to have functional thiol groups. In this study, the properties of thiol redox modulation of the ATP-sensitive $K^2$ ($K_{ATP}$) channel were examined in rabbit ventricular myocytes. Rabbit ventricular myocytes were isolated using a Langendorff column for coronary perfusion and collagenase. Single-channel currents were measured in excised membrane patch configuration of patch-clamp technique. The thiol oxidizing agent 5,5'-dithio-bis-(2-nitro-benzoic acid) (DTNB) inhibited the channel activity, and the inhibitory effect of DTNB was reversed by dithiothreitol (disulfide reducing agent; DTT). DTT itself did not have any effect on the channel activity. However, in the patches excised from the metabolically compromised cells, DTT increased the channel activity. DTT had no effect on the inhibitory action by ATP, showing that thiol oxidation was not involved in the blocking mechanism of ATP. There were no statistical difference in the single channel conductance for the oxidized and reduced states of the channel. Analysis of the open and closed time distributions showed that DTNB had no effect on open and closed time distributions shorter than 4 ms. On the other hand, DTNB decreased the life time of bursts and increased the interburst interval. N-ethylmaleimide (NEM), a substance that reacts with thiol groups of cystein residues in proteins, induced irreversible closure of the channel. The thiol oxidizing agents (DTNB, NEM) inhibited of the $K_{ATP}$ channel only, when added to the cytoplasmic side. The results suggested that metabolism-induced changes in the thiol redox can also modulate $K_{ATP}$ channel activity and that a modulatory site of thiol redox may be located on the cytoplasmic side of the $K_{ATP}$ channel in rabbit ventricular myocytes.

2,3-Dimethoxy-2′-hydroxychalcone ameliorates TNF-α-induced ICAM-1 expression and subsequent monocyte adhesiveness via NF-kappaB inhibition and HO-1 induction in HaCaT cells

  • Kim, Hyejin;Youn, Gi Soo;An, Soo Yeon;Kwon, Hyeok Yil;Choi, Soo Young;Park, Jinseu
    • BMB Reports
    • /
    • v.49 no.1
    • /
    • pp.57-62
    • /
    • 2016
  • Up-regulation of adhesion molecules plays an important role in the infiltration of leukocytes into the skin during the development of various inflammatory skin diseases, such as atopic dermatitis. In this study, we investigated the modulatory effects of 2,3-dimethoxy-2′-hydroxychalcone (DMHC) on tumor necrosis factor (TNF)-α-induced intercellular adhesion molecule-1 (ICAM-1) expression and monocyte adhesiveness, as well as the molecular mechanisms underlying its action in the HaCaT human keratinocyte cell line. Pre-treating HaCaT cells with DMHC significantly suppressed TNF-α-induced ICAM-1 expression and subsequent monocyte adhesiveness. DMHC inhibited TNF-α-induced activation of NF-ᴋB. In addition, DMHC induced HO-1 expression as well as NRF2 activation. Furthermore, HO-1 knockdown using siRNA reversed the inhibitory effect of DMHC on TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that DMHC may inhibit TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes by suppressing the signaling cascades leading to NF-ᴋB activation and inducing HO-1 expression in keratinocytes. [BMB Reports 2016; 49(1): 57-62]

Modulation of Sarcodon Aspratus on lon Currents-induced by Excitatory Neurotransmitters in Rat Periaqueductal Gray Neurons

  • Kim, Sung-Tae;Sung, Yun-Hee;Kim, Chang-Ju;Joo, Kwan-Joong;Han, Seung-Ho;Lee, Choong-Yeol;Kim, Youn-Sub
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.20 no.6
    • /
    • pp.1672-1677
    • /
    • 2006
  • Sarcodon aspratus is the mushroom of Telephoracea which was been classified into Alphllophorales. The aqueous extract of Sarcodon aspratus in known to have anti-tumor activity, immune modulatory effect, and anti-oxidative action. The descending pain control system consists of three major components: the periaqueductal gray (PAG) of the midbrain, the rostroventral medulla including the nucleus raphe magnus, and the spinal dorsal horn. Glutamate is the primary excitatory neurotransmitter in the brain. Glutamate ionotropic receptors are classified as N-methyl-D-aspartate (NMDA) receptor, ${\alpha}$-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor, and kainate receptor. In the present study, the modulation of Sarcodon aspratus on the ion currents activated by glutamate, NMDA, AMPA, and kainate in the acutely dissociated PAG neurons was investigated by nystatin-perforated patch-clamp technique under boltage-clamp condition. Sarcodon aspratus increased glutamate- and NMDA-induced ion currents were not increased by Sarcodon aspratus. The present results show that Sarcodon aspratus may activate the descending pain control system in rat PAG neurons through NMDA receptor.