• The Korean Journal of Physiology and Pharmacology
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• v.21 no.3
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• pp.287-292
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• 2017

Vitiligo is an intriguing depigmentary disorder and is notoriously difficult to be treated. The ultimate goal of vitiligo treatment is to replenish the lost melanocytes by immigration from hair follicle and to restore the normal function of melanogenesis by residual melanocytes. There are two types of topical calcineurin inhibitors called tacrolimus and pimecrolimus, and are recommended as the first-line treatments in vitiligo. Although pimecrolimus is efficacious for the repigmentation of vitiligo, its intrinsic mechanisms have never been investigated in vitro. This research aimed to study the ability of pimecrolimus on stimulating melanogenesis, melanocyte migration and MITF (microphthalmia associated transcription factor) protein expression. Results showed that pimecrolimus at the dosages of 1, 10, $10^2$nM were neither mitogenic nor cytotoxic to melanocytes. The addition of pimecrolimus at 10, $10^2$ and $10^3nM$ significantly increased intracellular tyrosinase activity, which was consistent with the elevated content of melanin content at the same concentrations. The peak effect was seen at 72 h in response to $10^2$nM pimecrolimus. Results of the wound scratch assay and Transwell assays indicate that pimecrolimus is effective in facilitating melanocyte migration on a collagen IV-coated surface. In addition, MITF protein yield reached the highest by pimecrolimus at $10^2nM$. In brief, pimecrolimus enhances melanin synthesis as well as promotes migration of melanocytes directly, possibly via their effects on MITF protein expression.

• Journal of dental hygiene science
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• v.15 no.4
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• pp.488-494
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• 2015

A recent report showed that nuclear factor of activated T cell (NFATc) 1 is a member of the NFAT family and is strictly implicated osteoblast differentiation and bone formation. Furthermore, the precise expression and function of NFATc1 in periodontal tissue remains unclear. Therefore, the purpose of this study was to investigate the function of NFATc1 in osteoblastic differentiation, and the underlying mechanism regulating periodontal regeneration in human periodontal ligament cells (hPDLCs). NFATc1 messenger RNA (mRNA) and protein levels were accessed by reverse transcription-polymerase chain reaction (RT-PCR) and western blot assay, respectively. Cell proliferation determined using MTT assay. Differentiation was evaluated by alkaline phosphatase activity and formation of calcium nodule with alizarin red S staining. The mRNA expression of osteoblastic differentiation related genes were examined by RT-PCR. Marked upregulation of NFATc1 mRNA and protein was observed in cells grown in osteogenic medium (OS). NFATc1 transactivation was detected in hPDLCs that had been incubated in OS for 14 days. Treatment with $10{\mu}M$ cyclosporine A (CsA), a known calcineurin inhibitor, reduced the proliferation of hPDLCs, while $5{\mu}M$ CsA had no effect. Inhibition of the calcineurin/NFATc1 pathway by CsA, attenuated OS-induced osteoblastic differentiation in hPDLCs. In summary, this study demonstrates for the first time that NFATc1 plays a key role in osteoblastic differentiation of hPDLCs and activation of NFATc1 could provide a novel mechanism for periodontal bone regeneration.

• Childhood Kidney Diseases
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• v.12 no.2
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• pp.133-142
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• 2008

For solid organ transplant, ABO blood type of donor and recipient should be compatible in principle. Recent improvement of immunosuppressant made HLA typing not so important while no-mismatch transplant still shows the longest graft survival. PRA(panel reactive antibody) test is to screen and identify recipients with HLA sensitization. When solid organ transplant is scheduled, cross-match test of donor cell and recipient serum should be performed and positive result of cross-match prohibits transplantation. Donor specific antibody(DSA) test can predict the severity of recipient immune reaction against donor organ. Today's mainstay of allograft immunosuppressant regimen is triple therapy of steroid, calcineurin inhibitor(cyclosporine, tacrolimus), azathioprine or mycophenolate mofetil(MMF). Antibody induction using Thymoglobulin or anti-IL-2 receptor antibody(basiliximab or daclizumab) is frequently practiced as well.

• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.189-193
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• 2005

IgE-dependent histamine-releasing factor(HRF) was initially described as a secretagogue for secretion of histamine from IgE+ basophils from a subset of allergic donors. Previously, we identified that S98 residue of HRF was phosphorylated using anti-HRFpS98 antibody which specifically recognizes the phosphorylated serine residue of HRF and HRFS98A mutant construct. In vitro kinase assay, only wild type HRF was phosphorylated by PKC, and S98A HRF was not affected by PKC. In this study, we attempted to characterize the phosphatase which specifically dephosphorylates HRF by immunoprecipitation and pull-down assay. In RBL-2H3 cells, HRF interacted only with calcineurin (also called as PP2B, calcium/calmodulin-dependent phosphatase) but not with PP1 or PP2A. The results suggest that HRF is most likely dephosphory-lated by calcineurin.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.5
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• pp.291-297
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• 2011

The effect of cyclosporin A (CsA), an immunosuppressant, on human ether-a-go-go-related gene (HERG) channel as it is expressed in human embryonic kidney cells was studied using a whole-cell, patch-clamp technique. CsA inhibited the HERG channel in a concentration-dependent manner, with an $IC_{50}$ value and a Hill coefficient of $3.17{\mu}m$ and 0.89, respectively. Pretreatment with cypermethrine, a calcineurin inhibitor, had no effect on the CsA-induced inhibition of the HERG channel. The CsA-induced inhibition of HERG channels was voltage-dependent, with a steep increase over the voltage range of the channel opening. However, the inhibition exhibited voltage independence over the voltage range of fully activated channels. CsA blocked the HERG channels predominantly in the open and inactivated states rather than in the closed state. Results of the present study suggest that CsA acts directly on the HERG channel as an open-channel blocker, and it acts independently of its effect on calcineurin activity.

• Journal of Ginseng Research
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• v.45 no.6
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• pp.683-694
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• 2021

Background: Ginsenoside Rg1 (Rg1) has been well documented to be effective against various cardiovascular disease. The aim of this study is to evaluate the effect of Rg1 on mechanical stress-induced cardiac injury and its possible mechanism with a focus on the calcium sensing receptor (CaSR) signaling pathway. Methods: Mechanical stress was implemented on rats through abdominal aortic constriction (AAC) procedure and on cardiomyocytes and cardiac fibroblasts by mechanical stretching with Bioflex Collagen I plates. The effects of Rg1 on cell hypertrophy, fibrosis, cardiac function, [Ca²⁺]_i, and the expression of CaSR and calcineurin (CaN) were assayed both on rat and cellular level. Results: Rg1 alleviated cardiac hypertrophy and fibrosis, and improved cardiac decompensation induced by AAC in rat myocardial tissue and cultured cardiomyocytes and cardiac fibroblasts. Importantly, Rg1 treatment inhibited CaSR expression and increase of [Ca²⁺]_i, which similar to the CaSR inhibitor NPS2143. In addition, Rg1 treatment inhibited CaN and TGF-b1 pathways activation. Mechanistic analysis showed that the CaSR agonist GdCl₃ could not further increase the [Ca²⁺]_i and CaN pathway related protein expression induced by mechanical stretching in cultured cardiomyocytes. CsA, an inhibitor of CaN, inhibited cardiac hypertrophy, cardiac fibrosis, [Ca²⁺]_i and CaN signaling but had no effect on CaSR expression. Conclusion: The activation of CaN pathway and the increase of [Ca²⁺]_i mediated by CaSR are involved in cardiac hypertrophy and fibrosis, that may be the target of cardioprotection of Rg1 against myocardial injury.

• Mycobiology
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• v.43 no.2
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• pp.150-156
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• 2015

2',4'-Dihydroxychalcone (2',4'-DHC) was identified from a heat shock protein 90 (Hsp90)-targeting library as a compound with Hsp90 inhibitory and antifungal effects. In the presence of 2',4'-DHC ($8{\mu}g/mL$), radial growth of Aspergillus fumigatus was inhibited 20% compared to the control, and green pigmentation was completely blocked. The expression of the conidiation-associated genes abaA, brlA, and wetA was significantly decreased (approximately 3- to 5-fold) by treatment with 2',4'-DHC. The expression of calcineurin signaling components, cnaA and crzA, was also significantly reduced. The inhibitory effects of 2',4'-DHC on metabolic activity and mycelial growth were significantly enhanced by combination treatment with itraconazole and caspofungin. Docking studies indicated that 2',4'-DHC bind to the ATPase domain of Hsp90. These results suggest that 2',4'-DHC act as an Hsp90-calcinurin pathway inhibitor.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.202.3-203
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• 2003

Calcineurin inhibitors, cyclosporine A (CsA) and tacrolimus (FK506), have been studied extensively regarding their effects on T lymphocytes, but their effects on dendritic cells (DC) are relatively unknown. DC can really capture Ag from dead and dying cells for presentation to MHC class I-restricted CTL. The main targets for the immunosuppressive calcinerin inhibitors, FK506 and CsA. have been considered to be activated T cells, but not antigen presenting cells (APCs). (omitted)

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2004.07a
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• pp.4-4
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• 2004

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1716-1722
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• 2018

Immunosuppressive drugs are used to make the body less likely to reject transplanted organs or to treat autoimmune diseases. In this study, five immunosuppressive drugs including two glucocorticoids (dexamethasone and prednisolone), one calcineurin inhibitor (cyclosporin A), one non-steroid anti-inflammatory drug (aspirin), and one antimetabolite (methotrexate) were tested for their effects on viral proliferation using feline foamy virus (FFV). The five drugs had different cytotoxic effects on the Crandell-Ress feline kidney (CRFK) cells, the natural host cell of FFV. Dexamethasone-pretreated CRFK cells were susceptible to FFV infection, but pretreatment with prednisolone, cyclosporin A, aspirin, and methotrexate showed obvious inhibitory effects on FFV proliferation, by reducing viral production to 29.8-83.8% of that of an untreated control. These results were supported by western blot, which detected viral Gag structural protein in the infected cell lysate. As our results showed a correlation between immunosuppressive drugs and susceptibility to viral infections, it is proposed that immune-compromised individuals who are using immune-suppressive drugs may be especially vulnerable to viral infection originated from pets.