• Journal of Ginseng Research
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• 제30권2호
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• pp.57-63
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• 2006

One of the various signaling agents in the animal cells is the simple ion called calcium, $Ca^{2+}$.$Ca^{2+}$ controls almost everything that animals do, including fertilization, secretion, metabolism, muscle contractions, heartbeat, learning, memory stores, and more. To do all of this, $Ca^{2+}$ acts as an intracellular messenger, relaying information within cells to regulate their activity. In contrast, the maintenance of intracellular high $Ca^{2+}$ concentrations caused by various excitatory agents or toxins can lead to the disintegration of cells (necrosis) through the activity of $Ca^{2+}$-sensitive protein-digesting enzymes. High concentrations of calcium have also been implicated in the more orderly programs of cell death known as apoptosis. Because this simple ion, acts as an agent for cell birth, life and death, to coordinate all of these functions, $Ca^{2+}$ signalings should be regulated precisely and tightly. Recent reports have shown that ginsenosides regulate directly and indirectly intracellular $Ca^{2+}$ level with differential manners between neuronal and non-neuronal cells. This brief review will attempt to survey how ginsenosides differentially regulate intracellular $Ca^{2+}$ signaling mediated by various ion channels and receptor activations in neuronal and non-neuronal cells.

• International Journal of Oral Biology
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• 제45권2호
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• pp.64-69
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• 2020

Short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are secondary metabolites produced by anaerobic fermentation of dietary fibers in the intestine. Intestinal SCFAs exert various beneficial effects on intestinal homeostasis, including energy metabolism, autophagy, cell proliferation, immune reaction, and inflammation, whereas contradictory roles of SCFAs in the oral cavity have been reported. Herein, we found that low and high concentrations of SCFAs induce differential regulation of intracellular Ca²⁺ mobilization and expression of pro-inflammatory cytokines, such as interleukin (IL)-6 and IL-8, respectively, in gingival fibroblast cells. Additionally, cell viability was found to be differentially regulated in response to low and high concentrations of SCFAs. These findings demonstrate that the physiological functions of SCFAs in various cellular responses are more likely dependent on their local concentration.

• BMB Reports
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• 제38권4호
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• pp.432-439
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• 2005

$Ca^{2+}$/calmodulin transduction pathways have been implicated in mediating stress response and tolerance in plants. Here, three genes encoding calmodulin (Cam) members of the EF-hand family of $Ca^{2+}$-binding proteins were identified from Oryza sativa L. databases. Complementary DNA for each of the calmodulin genes, OsCam1, OsCam2, and OsCam3 were sequenced. OsCam1 and OsCam2 encode a conventional 148-amino acid calmodulin protein that contains four characteristic $Ca^{2+}$-binding motifs. OsCam3 encode a similar protein with a 38-amino-acid extension containing a putative prenylation site (CVIL) at the carboxyl terminus. RT-PCR showed that each of the genes is expressed in leaves and roots of 2-week old rice seedlings. By RNA gel blot analysis, OsCam1 mRNA levels strongly increased in response to NaCl, mannitol and wounding treatments. In contrast, OsCam2 mRNA levels were relatively unchanged under all conditions investigated. NaCl treatment and wounding also increased the OsCam3 mRNA level, but in a more transient manner. Our results indicate that although the expression of genes encoding different calmodulin isoforms is ubiquitous, they are differentially regulated by various stress signals. In addition, we have demonstrated that the calcium-channel blocker lanthanum chloride inhibited the induction of OsCam1 gene expression by both NaCl and mannitol treatments. These results suggest that osmotic stress induced expression of OsCam1 gene requires the $[Ca^{2+}]_{cyt}$ elevation that is known to occur in response to these stimuli.

• Biomolecules & Therapeutics
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• 제20권4호
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• pp.386-392
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• 2012

The endothelin (ET) signaling pathway controls many physiological processes in myocardium and often becomes upregulated in heart diseases. The aim of the present study was to investigate the effects of ET receptor upregulation on the contractile function of adult ventricular myocytes. Primary cultured adult rat ventricular myocytes were used as a model system of ET receptor overexpression in the heart. Endothelin receptor type A ($ET_A$) or type B ($ET_B$) was overexpressed by Adenoviral infection, and the twitch responses of infected ventricular myocytes were measured after ET-1 stimulation. Overexpression of $ET_A$ exaggerated positive inotropic effect (PIE) and diastolic shortening of ET-1, and induced a new twitch response including twitch broadening. On the contrary, overexpression of $ET_B$ increased PIE of ET-1, but did not affect other two twitch responses. Control myocytes expressing endogenous receptors showed a parallel increase in twitch amplitude and systolic $Ca^{2+}$ in response to ET-1. However, intracellular $Ca^{2+}$ did not change in proportion to the changes in contractility in myocytes overexpressing $ET_A$. Overexpression of $ET_A$ enhanced both systolic and diastolic contractility without parallel changes in $Ca^{2+}$. Differential regulation of this nature indicates that upregulation of $ET_A$ may contribute to diastolic myocardial dysfunction by selectively targeting myofilament proteins that regulate resting cell length, twitch duration and responsiveness to prevailing $Ca^{2+}$.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.208-208
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• 1996

In this work we investigated coupling of the m2 and m4 subtypes of muscarinic acetylcholine receptors expressed in chinese hamster ovary (CHO) cells to activation of neuronal nitric oxide synthase (nNOS). Stimulation of guanylate cyclase activity in detector neuroblastoma cells was used as an index of generation of nitric oxide (NO) in CHO cells. The agonist carbachol induced marked time and concentration-dependent enhancement of the activity of nNOS at m2 receptors. In sharp contrast, the response in CHO cells transfected with the m4 receptor gene was similar in magnitude to that observed in non-transfected cells, suggesting lack of significant coupling of m4 muscarinic receptors to NO signaling. This novel observation of functional divergence of the two muscarinic receptor subtypes at the level of activation of nNOS is quite intriguing, in light of the currently accepted dogma that they belong to the same functional class. This functional selectivity was not due to differential effects on intracellular Ca$\^$2+/ concentration, since activation of both subtypes of muscarinic receptors produced a comparable, albeit quite small, Ca$\^$2+/ signal. Taken together, our present data strongly suggest that the generally assumed functional equivalence of m2 and m4 muscarinic receptors should be carefully reexamined. These data also suggest the presence of alternate mechanisms of activation of nNOS, which might be operative in the absence of large changes in the concentration of cellular Ca$\^$2+/. The latter mechanisms are expected to be activated by m2, but not m4 muscarinic receptors. Both sets of findings are quits important in regards to refining the functional classification of muscarinic receptor subtypes and the cellular mechanisms of activation of NOS.

• 생명과학회지
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• 제29권7호
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• pp.809-816
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• 2019

p-Coumaric acid (p-CA)는 항산화 및 항염 활성을 가진 식물계에서 가장 풍부한 식물화학물질이다. 그러나 위암세주포에서 p-CA의 항암 활성과 전사체 발현에 대한 연구는 아직까지 수행된 바 없다. 본 연구에서는 SNU-16 위암세포에서 p-CA에 의한 세포 증식 억제 및 전사체 프로파일에 미치는 영향을 조사하였다. p-CA는 세포사멸 단백질 발현을 조절하여 SNU-16 세포에서의 세포사멸을 유도하였다. RNA-seq 분석을 사용하여 p-CA처리에 의해 SNU-16 세포에서 차별적으로 발현된 유전자(DEGs)를 동정하였다. DEGs들의 gene ontology (GO) 술어로 유전자 산물을 검색한 결과, 주로 염증반응, 세포사멸 과정, 세포주기 및 면역 반응에 관여하는 생물학적 과정에 관여하는 것으로 나타났다. 또한, KEGG 경로분석 결과, p-CA는 주로 PI3K-Akt 와 암 신호전달 경로에 변화를 유발하였다. 본 연구결과는 p-CA가 세포증식과 암 신호 전달 경로에 관여하는 유전자 발현을 조절함으로써 위암 예방 효과를 나타낼 수 있음을 시사한다.

• Journal of Plant Biotechnology
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• 제33권2호
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• pp.93-97
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• 2006

농작물 생산에 있어서 병원균 침입에 의한 피해를 줄이는 것은 아주 중요한 과제이다. 식물은 스스로도 생체 방어 신호 전달 기작을 가지고 있지만 그 피해를 줄이는데 있어서 한계가 있다. 본 연구는 콩과 식물에서 분리한 식물생체방어 신호전달 유전자인 SCaM-5를 토마토에 형질전환하여 형질전환 식물체를 작성하고 병 저항성에 관한 실험을 수행한 것이다. SCaM-5 유전자가 형질전환 된 토마토에서는 pathogen-related(PR-5) 유전자를 항상 발현시킴으로서 계속적으로 식물 생체방어 신호기작을 활성 시킨다는 사실을 확인하였다. 또한, SCaM-5를 형질전환 시킨 토마토는 식물에 막대한 피해를 주는 중요한 곰팡이 (P. capsici와 F. oxysporm)와 bacteria (Pst DC3000)에 대하여 병 저항성을 가진다는 것을 검증하였다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권1호
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• pp.36-41
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• 2006

Objective. The objective of this study was to examine the hypothesis that inflammatory synovial fluid from TMJ internal derangement initiates a transient increase in intracellular calcium concentration ([$Ca^{2+}$]i) in chondrocytes and the induced Ca2+ signaling affects iNOS/COX-2 gene expression patterns following exposure to inflamed synovial fluid. Materials and Methods. Two female adult patients with symptoms of TMD who agreed to participate in the study were selected for this study. Immortalized human juvenile costal chondrocyte C-28/I2 was grown to 80% confluency and synovial fluids from two patients were added respectively to culture media for 24 hours at the concentration of 100ng/10ml. Confocal laser scanning microscope (CLSM) was used to examine changes of intracellular calcium concentration ([$Ca^{2+}$]i). RT-PCR was performed to identify the expression profile of IL-1${\alpha}$, iNOS, COX-2. Results. Increased [$Ca^{2+}$]i was observed in chondrocytes subjected to inflamed synovial fluid compared to control cultures and in respective cultures exposed to inflamed synovial fluids from each patient, IL-1${\beta}$, COX-2 mRNA were detected. However, in neither case iNOS mRNA was expressed. IL-1${\alpha}$, COX-2, and iNOS mRNA were expressed in control culture. Conclusion. Our results show that immortalized chondrocytes cultured with inflamed synovial fluids from patients diagnosed as disc displacement without reduction and limitation in mouth opening showed increased calcium concentration and expression of COX-2 while inhibiting the production of iNOS, which in turn could adversely affect the chondrocytes in at least short term by hindering physiologic role of NO against inflammatory cascades. These findings suggest that inflamed synovial fluid may differentially regulate the transcriptomes of relevant inflammatory mediators, especially iNOS/COX-2 axis in chondrocytes through adjusting calcium transients.

• Journal of Ginseng Research
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• 제47권1호
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• pp.133-143
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• 2023

Background: Past studies suggested that ginseng extracts and ginseng-derived molecules exerted significant regulatory effects on skin. However, no reports have described the effects of ginseng-derived nanoparticles (GDNPs) on skin cell proliferation and wound healing. In this study, we investigated whether GDNPs regulate the proliferation of skin cells and promote wound healing in a mouse model. Methods: GDNPs were separated and purified via differential centrifugation and sucrose/D2O gradient ultracentrifugation. GDNP uptake, cell proliferation and cell cycle progression were measured by confocal microscopy, CCK-8 assay and flow cytometry, respectively. Cell migration and angiogenic effects were assessed by the wound scratch assay and tube formation assay, respectively. ELISA was used to detect extracellular matrix secretion. The relevant signaling pathway was confirmed by western blotting. The effects of GDNPs on skin wound healing were assessed by wound observation, HE staining, and western blotting. Results: GDNPs possessed the essential features of exosomes, and they were accumulated by skin cells. Treatment with GDNPs notably enhanced the proliferation of HaCaT, BJ and HUVECs. GDNPs also enhanced the migration in HaCaT cells and HUVECs and angiogenesis in HUVECs. GDNPs increased the secretion of MMP-1, fibronectin-1, elastin-1, and COL1A1 in all three cell lines. GDNPs regulated cell proliferation through the ERK and AKT/ mTOR pathways. Furthermore, GDNPs facilitated skin wound healing and decreased inflammation in a mouse skin wound model. Conclusion: GDNPs can promote skin wound healing through the ERK and AKT/mTOR pathways. GDNPs thus represent an alternative treatment for chronic skin wounds.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.206-206
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• 1996

The C-terminus ends of the second putative transmembrane domains of both m1 and m2 muscarinic receptors contain a triplet of amino acid residues consisting of leucine (L), tyrosine (Y) and threonine (T), This triplet is repeated as LYT-LYT in m2 receptors at the interface between the second transmembrane domain and the first extracellular loop. Interestingly, however, it is repeated in a transposed fashion (LYT-TYL) in the sequence of m1 receptors. In this work we employed site-directed mutagenesis to investigate the possible significance of this unique sequence diversity for determining the distinct differential drug-receptor interaction and cellular function at m1 muscarinic receptor. Mutation of the LYTTYL sequence of m1 receptors to the corresponding m2 receptor LYTLYT sequence, however, did not result in a significant change in the binding affinity of the agonist carbachol or in the affinity of the majority of a series of receptor antagonists which are able to discriminate between wild-type m1 and m2 receptors. Surprisingly, the LYTLYT ml receptor mutant demonstrated markedly enhanced coupling to activation of phospholipase C without a change in its coupling to increased cyclic AMP formation. There was also an enhanced receptor sensitivity in transducing elevation of intracellular Ca$\^$2+/. These changes were not due to alterations in the rate of receptor. desensitization or sequestration, On the other hand, the reverse LYTLYT-LYTTYL mutation in the m2 receptor did not alter its coupling to inhibition of adenylate cyclase, but slightly enhanced its coupling to stimulation of PI hydrolysis, Our data suggest that the LYTTYL/LYTLYT sequence difference between ml and n12 muscarinic receptors is not involved in determining receptor pharmacology. On the other hand, while these differences might play a role in the modulation of muscarinic receptor coupling to PI hydrolysis, they are not important for specifying coupling of various subtypes of muscarinic receptors to different cellular signaling pathways.