• The Korean Journal of Physiology and Pharmacology
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• v.21 no.1
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• pp.1-9
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• 2017

Intestinal disorders often co-occur with inflammation and dysmotility. However, drugs which simultaneously improve intestinal inflammation and co-occurring dysmotility are rarely reported. Atractylodin, a widely used herbal medicine, is used to treat digestive disorders. The present study was designed to characterize the effects of atractylodin on amelioration of both jejunal inflammation and the co-occurring dysmotility in both constipation-prominent (CP) and diarrhea-prominent (DP) rats. The results indicated that atractylodin reduced proinflammatory cytokines TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 in the plasma and inhibited the expression of inflammatory mediators iNOS and NF-kappa B in jejunal segments in both CP and DP rats. The results indicated that atractylodin exerted stimulatory effects and inhibitory effects on the contractility of jejunal segments isolated from CP and DP rats respectively, showing a contractile-state-dependent regulation. Atractylodin-induced contractile-state-dependent regulation was also observed by using rat jejunal segments in low and high contractile states respectively (5 pairs of low/high contractile states). Atractylodin up-regulated the decreased phosphorylation of 20 kDa myosin light chain, protein contents of myosin light chain kinase (MLCK), and MLCK mRNA expression in jejunal segments of CP rats and down-regulated those increased parameters in DP rats. Taken together, atractylodin alleviated rat jejunal inflammation and exerted contractile-state-dependent regulation on the contractility of jejunal segments isolated from CP and DP rats respectively, suggesting the potential clinical implication for ameliorating intestinal inflammation and co-occurring dysmotility.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.385-391
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• 2010

This study was conducted to compare proteins expressed in M. longissimus from Hanwoo and Holstein steers immediately after slaughter. Two-dimensional electrophoresis (2DE)/LC-MS/MS analysis revealed that the total number of detectable protein spots from longissimus muscle tissues was slightly higher in Hanwoo ($575{\pm}65$) than Holstein ($534{\pm}13$) steers, but that these numbers were not statistically significant due to large variation between replicates. A total of twelve protein spots did not match between sample groups, eight of which were expressed in the Hanwoo sample and four that were expressed in the Holstein sample. The protein spots detected in the Hanwoo sample included smooth muscle and non-muscle myosin alkali light chain 6B isomers, ${\alpha}B$ crystallin isomers, hemoglobin ${\beta}$-A chains, slow myosin heavy chains, and slow skeletal muscle troponin T chains. Collectively, these proteins are a class of slow-twitch muscle fiber and mirror that Hanwoo muscle tissue sampled for the current study contained more slow-twitch muscle fibers than Holstein one. Conversely, proteins detected from the Holstein sample included ankyrin repeat domain 2 and creatin kinase isomers. Given that creatin kinase isomers are related to the fast-twitch muscle, these results likely indicate that Holstein muscle tissue sampled for the current study contained more fast-twitch muscle fibers than Hanwoo beef.

• Journal of Korean Physical Therapy Science
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• v.11 no.1
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• pp.20-27
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• 2004

It is widely accepted that smooth muscle contraction is triggered by intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) released from intracellular $Ca^{2+}$ stores such as sarcoplasmic reticulum (SR) and from the extracellular space, The increased $[Ca^{2+}]_i$ can phosphorylate the 20-kDa myosin light chain ($MLC_{20}$) by activating MLC kinase (MLCK), and this initiates smooth muscle contraction. In addition to the $[Ca^{2+}]_i$-MLCK-tension pathway, a number of intracellular signal molecules, including mitogen-activated protein kinase (MAPK), protein kinase C (PKC), phosphatidylinositol 3-kinase (PI3K), and Rho-associated coiled coil-forming protein kinase (ROCK), play important roles in the regulation of smooth muscle contraction. However, the mechanisms regulating contraction of caldesmon (CaD), actin-binding protein, are not entirely elucidated in the presence of $Ca^{2+}$. It is known that CaD tightly interacts with actin and inhibits actomyosin ATPase activity. Therefore, the purpose of the present study was to investigate the roles of $Ca^{2+}$-dependent CaD in smooth muscle contraction. Endothelin-1 (ET-1), G-protein coupled receptor agonist and vasoconstrictor, increased both vascular smooth contraction and phosphorylation of CaD in the presence of $Ca^{2+}$. These results suggest that ET-1 induces contraction and phosphorylation of CaD in rat aortic smooth muscle, which may he mediated by the increase of $[Ca^{2+}]_i$.

• Molecules and Cells
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• v.27 no.2
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• pp.175-181
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• 2009

The myosin light chain kinase (MYLK) gene encodes both smooth muscle and nonmuscle cell isoforms. Recently, polymorphisms in MYLK have been reported to be associated with several diseases. To examine the genetic effects of polymorphisms on the risk of asthma and related phenotypes, we scrutinized MYLK by re-sequencing/genotyping and statistical analysis in Korean population (n = 1,015). Seventeen common polymorphisms located in or near exons, having pairwise $r^2$ values less than 0.25, were genotyped. Our statistical analysis did not replicate the associations with the risk of asthma and log-transformed total IgE levels observed among African descendant populations. However, two SNPs in intron 16 (+89872C> G and +92263T> C), which were in tight LD (|D'| = 0.99), revealed significant association with log-transformed blood eosinophil level even after correction multiple testing ($P=0.002/P^{corr}=0.01$ and $P=0.002/P^{corr}=0.01$, respectively). The log-transformed blood eosinophil levels were higher in individuals bearing the minor alleles for +89872C> G and +92263T> C than in those bearing other allele. In additional subgroup analysis, the genetic effects of both SNPs were much more apparent among asthmatic patients and atopic asthma patients. Among atopic asthma patients, the log-transformed blood eosinophil levels were proportionally increased by gene-dose dependent manner of in both +89872C> G and +92263T> C(P = 0.0002 and P = 0.00007, respectively). These findings suggest that MYLK polymorphisms might be among the genetic factors underlying differential increases of blood eosinophil levels among asthmatic patients. Further biological and/or functional studies are needed to confirm our results.

• The Journal of Korean Physical Therapy
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• v.19 no.5
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• pp.65-76
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• 2007

Purpose: It is generally accepted that smooth muscle contraction is triggered by intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) released from intracellular $Ca^{2+}$ stores such as sarcoplasmic teticulum (SR) and from the extracellular space. The increased $[Ca^{2+}]^i$ can phosphorylate the 20,000 dalton myosin light chain $(MLC_{20})$ by activating MLC kinase (MLCK), and this initiates smooth muscle contraction. In addition to the $[Ca^{2+}]_i$MACK-tension pathway, a number of intracellular signal molecules, including mitogen-activated protein kinase (MAPK), protein kinase C (PKC) and others, play important roles in the regulation of smooth muscle contraction. However, the mechanisms regulating contraction of depletion of SR $Ca^{2+}$ in mouse gastric smooth muscle strips is not still clear. Methods: To investigate the rotes of $Ca^{2+}$ influx and SR $Ca^{2+}$ release channel on gastric motility, isometric contraction and $[Ca^{2+}]_i$ were examined in mouse gastric smooth muscle strips. Results: High KCl, ryanodine, an activator of $Ca^{2+-}$induced $Ca^{2+}$ release channel, and cyclopiazonic acid (CPA), an inhibitor of SR $Ca^{2+-}$ATPase evoked a sustained increase in muscle contraction and $[Ca^{2+}]_i$. These increases induced by high KCl, ryanodine, and CPA were partially blocked by application of verapamil ($10{\mu}M$), a L-type $Ca^{2+}$ channel inhibitor. Additionally, in $Ca^{2+-}$free solution (1 mM EGTA), ryanodine and CPA had no effect contraction and $[Ca^{2+}]_i$ in fundic muscle strips. Conclusion: These results that extracellular $Ca^{2+}$ influx and depletion of SR trigger $Ca^{2+}$ influx through verapamil-sensitive $Ca^{2+}$ channel, and extracellular and SR $Ca^{2+}$ store may functionally involve in the subcellular $Ca^{2+}$ mobilization in mouse gastric muscle.

• Animal cells and systems
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• v.5 no.3
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• pp.253-262
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• 2001

Ligand-receptor clustering event is the most important step in leukocyte adhesion and spreading on endothelial cells. Intercellular adhesion molecule-1 (ICAM-1) has been shown to enhance leukocyte adhesion, but the molecular event during the process of adhesion is unclear. To visualize the dynamics of ICAM-1 movement during adhesion, we have engineered stable Chinese hamster ovary cell lines expressing ICAM-1 fused to a green fluorescent protein (IC1_GFP/CHO) and examined them under the fluorescence microscopy. The transfection of IC1_GFP alone in these cells was sufficient to support the adhesion of K562 cells that express $\alpha$L$\beta$2 (LFA-1) integrin stimulated by CBR LFA-1/2 mAb. This phenomenon was mediated by ICAM-1-LFA-1 interactions, as an mAb that specifically inhibits ICAM-1-LFA-1 interaction (RRl/l) completely abolished the adhesion of LFA-1＊ cells to IC1_ GFP/CHO cells. We found that the characteristic of adhesion was followed almost immediately (~10 min) by the rapid accumulation of ICAM-1 on CHO cells at a tight interface between the two cells. Interestingly, ICI_GFP/CHO cells projected plasma membrane and encircled approximately half surface of LFA-1+ cells, as defined by confocal microscopy. This unusual phenomenon was also confirmed on HUVEC after adhesion of LFA-1＊ cells. Neither cytochalasin D nor 2,3-butanedione 2-monoxime an inhibitor of myosin light chain kinase blocked LFA-1-mediated ICAM-1 clustering, indicating that actin cytoskeleton and myosin-dependent contractility are not necessary for ICAM-1 clustering. Taken together, we suggest that leukocyte adhesion to endothelial cells induces specialized form of ICAM-1 clustering that is distinct from immunological synapse mediated by T cell interaction with antigen presenting cells.

• Journal of Ginseng Research
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• v.34 no.3
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• pp.212-218
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• 2010

Korean red ginseng (KRG) has been shown to enhance endothelium-dependent vasorelaxation in experimental animals; however, little is known about its pharmacological effects on vascular stiffness in patients with coronary artery disease (CAD). This randomized, double-blind, placebo-controlled crossover trial was carried out to determine whether KRG has beneficial effects on arterial stiffness, cardiovascular risk factors such as plasma lipid profiles and blood pressure (BP), and Rho-associated kinase (ROCK) activity. Twenty patients (mean age, 62.5 years) with stable angina pectoris were given KRG (2.7 g/day) and a placebo alternatively for 10 weeks. Blood biochemical analysis and pulse wave velocity (PWV) recording were performed on day 0 and after the completion of each treatment. ROCK activity was assessed based on the level of phospho-$Thr^{853}$ in the myosin-binding subunit of myosin light chain phosphatase, determined by Western blot analysis of peripheral blood mononuclear cells. KRG significantly decreased the systolic BP, brachial ankle PWV, and heart femoral PWV in the patients (all p<0.05), but did not significantly alter the serum lipid profiles, including triglycerides and total, high-density lipoprotein, and low-density lipoprotein cholesterol levels. The ROCK activity tended to decrease (p=0.068) following KRG treatment. The placebo did not significantly alter any of the variables. In conclusion, KRG decreased systolic BP and arterial stiffness, probably via the inhibition of ROCK activity, in patients with CAD, but had a neutral effect on serum lipid profiles. Our data suggest that KRG has a therapeutic effect on CAD.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.1
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• pp.99-106
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• 2017

Obesity is a critical risk factor for the hypertension. Although angiotensin II (Ang II) in obese individuals is known to be upregulated in obesity-induced hypertension, direct evidence that explains the underlying mechanism for increased vascular tone and consequent increase in blood pressure (BP) is largely unknown. The purpose of this study is to investigate the novel mechanism underlying Ang II-induced hyper-contractility and hypertension in obese rats. Eight-week old male Sprague-Dawley rats were fed with 60% fat diet or normal diet for 4 months. Body weight, plasma lipid profile, plasma Ang II level, BP, Ang II-induced vascular contraction, and expression of regulatory proteins modulating vascular contraction with/without Ang II stimulation were measured. As a result, high fat diet (HFD) accelerated age-dependent body weight gaining along with increased plasma Ang II concentration. It also increased BP and Ang II-induced aortic contraction. Basal expression of p-CPI-17 and myosin light chain (MLC) kinase was increased by HFD along with increased phosphorylation of MLC. Ang II-induced phosphorylation of CPI-17 and MLC were also higher in HFD group than control group. In conclusion HFD-induced hypertension is through at least in part by increased vascular contractility via increased expression and activation of contractile proteins and subsequent MLC phosphorylation induced by increased Ang II.

• YAKHAK HOEJI
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• v.53 no.3
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• pp.156-160
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• 2009

The present study was undertaken to determine whether transgelin participates in the regulation of vascular smooth muscle contraction and, if so, to investigate the mechanism. By PCR homology cloning, the cDNA sequence of ferret transgelin was determined and phosphorothioate antisense and random oligonucleotides were synthesized and introduced into strips of ferret aorta by a chemical loading procedure. Treatment of ferret aorta with transgelin antisense oligonucleotides resulted in a significant decrease in protein levels of transgelin to sham- or random sequence-loaded muscles, but no change in the protein levels of actin. Contraction in response to a phorbol ester was significantly decreased in antisense-treated muscles compared to sham- or random sequence-loaded controls. Neither basal intrinsic tone nor the contraction in response to phenylephrine was significantly affected by the antisense treatment. The data indicate that transgelin plays a significant role in the regulation of contraction and suggest that in a tonically active smooth muscle transgelin may function as a signalling protein to facilitate PKC or ERK-dependent signalling rather than thick filament regulation including $Ca^{2+}$ or calmodulin dependent regulation of myosin light chain kinase.

• BMB Reports
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• v.51 no.4
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• pp.182-187
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• 2018

In carcinoma, cancer-associated fibroblasts participate in force-mediated extracellular matrix (ECM) remodeling, consequently leading to invasion of cancer cells. Likewise, the ECM remodeling actively occurs in glioblastoma (GBM) and the consequent microenvironmental stiffness is strongly linked to migration behavior of GBM cells. However, in GBM the stromal cells responsible for force-mediated ECM remodeling remain unidentified. We show that tumor-associated mesenchymal stem-like cells (tMSLCs) provide a proinvasive matrix condition in GBM by force-mediated ECM remodeling. Importantly, CCL2-mediated Janus kinase 1 (JAK1) activation increased phosphorylation of myosin light chain 2 in tMSLCs and led to collagen assembly and actomyosin contractility. Collectively, our findings implicate tMSLCs as stromal cells providing force-mediated proinvasive ECM remodeling in the GBM microenvironment, and reminiscent of fibroblasts in carcinoma.