• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1086-1093
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• 2018

Honokiol, a bioactive compound isolated from the cone and bark of Magnolia officinalis, has been shown to have various activities including inhibition of the growth of Candida albicans. We investigated the roles of the Hsp90-calcineurin pathway in the antifungal activity of honokiol. The pharmacologic tool was employed to evaluate the effects of Hsp90 and calcineurin in the antifungal activity of honokiol. We also evaluated the protective effects of the calcineurin inhibitor cyclosporin A (CsA) on honokiol-induced mitochondrial dysfunction by the fluorescence staining method. The Hsp90 inhibitor potentiated the antifungal activity of honokiol. A C. albicans strain with the calcineurin gene deleted displayed enhanced sensitivity to honokiol. However, co-treatment with calcineurin inhibitor CsA attenuated the cytotoxic activity of honokiol due to the protective effect on mitochondria. Our results provide insight into the action mechanism of honokiol.

• IMMUNE NETWORK
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• v.6 no.1
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• pp.33-42
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• 2006

Background: Calcineurin plays a crucial role in T cell activation, cell growth, apoptosis, and angiogenesis, and its over-expression has been implicated in the pathogenesis of cardiomyopathy and stroke. However, the expression and function of calcineurin in the pathologic lesion of chronic inflammatory diseases, like rheumatoid synovium, remain to be defined. This study was aimed to determine the role of calcineurin in inflammatory arthritis and investigate the expression and function of calcineurin in the rheumatoid synovium and synoviocytes, the actual site of chronic inflammation. Methods: Immuno-histochemical staining using specific antibody to calcineurin was perfomed in the synovium of rheumatoid arthritis (RA). Fibroblast-like synoviocytes (FLS) from RA and osteoarthritis (OA) patients were isolated from RA and OA patients, and cultured with IL-1${\beta}$ and TNF-${\alpha}$ in the presence or absence of cyclosporin A, a calcineurin inhibitor. The calcineurin expression was assessed by phosphatase assay and Western blotting analysis. IL-6, -10, -17, matrix metalloproteinase (MMP)-1, -2, -3, and -9 released into the culture supernatants were measured by ELISA. After transfection with GFP-Cabin 1 gene into synoviocytes, the levels of IL-6 and MMPs were measured by ELISA. Results: Calcineurin was highly expressed in the lining layer of synovium and cultured synoviocytes of RA patients. The elevated calcineurin activity in the rheumatoid synoviocytes was triggered by proin flammatory cytokines such as IL-1${\beta}$ and TNF-${\alpha}$. In contrast, IL-10, an anti-inflammatory cytokine, failed to increase the calcineurin activity. The targeted inhibition of calcineurin by the over-expression of Cabin 1, a natural calcineurin antagonist, inhibited the production of IL-6 and MMP-2 by rheumatoid synoviocytes in a similar manner to the calcineurin inhibitor, cyclosporin A. Conclusion: These data suggest that abnormal activation of calcineurin in the synoviocytes may contribute to the pathogenesis of chronic arthritis, and thus provide a potential target for controlling inflammatory arthritis.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1429-1432
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• 2015

To identify plant-derived cell signaling inhibitors with antifungal properties, a twocomponent screening system using both wild-type Cryptococcus neoformans and a calcineurin mutant was employed owing to their counter-regulatory actions on the Hog1 mitogenactivated protein kinase and calcineurin pathways. Of the 2,000 plant extracts evaluated, a single bioactive compound from M. obovata Thunb. was found to act specifically on the calcineurin pathway of C. neoformans. This compound was identified as magnoloside A, and had potent antifungal activities against various Cryptococcus strains with minimum inhibitory concentration values ranging from 1.0 to 4.0 μg/ml.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1055-1060
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• 2004

A new inhibitor for peptidylprolyl cis-trans isomerase (PPIase) has been isolated from Ganoderma lucidum and purified to homogeneous state by organic solvent extraction. The purified PPIase inhibitor (GPI) is assumed to be a membrane-associated glycoprotein. GPI inhibits specifically the bovine brain PPIase, a cyclophilin, and has no effect on the FKBP activity. The results of our chemical modification study of GPI indicate the presence of Lys residue(s) at or near its binding site. Like CsA-cyclophilin complex, GPI-bovine brain PPIase complex strongly inhibits the calcineurin activity in vitro, suggesting the possible involvement of GPI in immunomodulating pathway by the formation of PPIase-inhibitor-calcineurin complex.

• Korean Journal of Transplantation
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• v.28 no.3
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• pp.165-168
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• 2014

The recipient candidate was a 51-year-old male with end-stage renal disease owing to diabetes mellitus. The initial immunosuppressive regimen included basiliximab for induction and tacrolimus, mycophenolate mofetil, and steroids. Urine output was 413 mL/day on the operative day and 100 mL/day on the postoperative day (POD) 1. There was no definite stenosis of the ureter or vessels. He had anuria on POD 2~4 and he had undergone hemodialysis. His serum creatinine level did not decrease. Therefore, a graft biopsy was performed on POD 4. The pathologic finding was consistent with acute calcineurin inhibitor (CNI) toxicity. There was no evidence of rejection or acute tubular necrosis. Anuria continued on POD 6; therefore, we started sirolimus instead of a CNI based regimen. Graft function was gradually recovered 1 day after reduction of CNI dose and hemodialysis was stopped. The serum creatinine level was normalized on POD 10. He was discharged on POD 21.

• Molecules and Cells
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• v.22 no.1
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• pp.1-7
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• 2006

The NFAT family of transcription factors plays pivotal roles in the development and function of the immune system. Their activation process is tightly regulated by calcium-dependent phosphatase calcineurin and has been a target of the immunosuppressive drugs cyclosporin A and FK-506. Although the clinical use of these drugs has dramatically increased the success of organ transplantation, their therapeutic use is limited by severe side effects. Recent studies for the calcineurin/NFAT signaling pathway have identified a number of cellular proteins that inhibit calcineurin function. Specific peptide sequences that interfere with the interaction between calcineurin and NFAT have also been characterized. Moreover, diverse approaches to identify small organic molecules that modulate NFAT function have been performed. This review focuses on the recent advances in our understanding of the inhibitory modulation of NFAT function, which may open up the additional avenues for immunosuppressive therapy.

• Journal of Life Science
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• v.25 no.2
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• pp.223-230
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• 2015

Regulator of calcineurin 1 (RCAN1) is an endogenous calcineurin inhibitor that plays an important role in the pathogenesis of diseases related to the calcineurin-NFATc1 signaling pathway. The RCAN1-4 isoform is subject to NFATc1-dependent regulation. During receptor activator of nuclear factor kappa-B ligand (RANKL)-stimulated osteoclastogenesis, the calcineurin-NFATc1 pathway is critical. Because there is little information available on the role of RCAN1 in osteoclast differentiation, this study investigated whether changes in RCAN1 expression are related to the calcineurin-NFATc1 pathway and osteoclast differentiation. Mouse bone marrow monocytes (BMMs) were treated with 50 ng/ml of RANKL and M-CSF. Expression levels of NFATc1, calcineurin, and RCAN1 isoforms were determined using RT-PCR and Western blotting. Osteoclast differentiation was examined using tartrate-resistent acid phosphatase (TRAP) staining. To evaluate the effect of RCAN1 overexpression on osteoclastogenesis, cells were transfected with a mouse RCAN1-4 cDNA plasmid. After RANKL stimulation of BMMs, expression of NFATc1 and RCAN1 was increased at the mRNA and protein level, while calcineurin expression was unchanged. When the RCAN1-4 gene construct was transfected, the expression of RCAN1 protein was not increased despite several-fold increases in RCAN1-4 mRNA expression. Regardless of RANKL stimulation, over-expression of RCAN1-4 tended to reduce NFATc1 expression and knock-down of RCAN1 increase it. While BMMs transfected with the RCAN1-4 vector were differentiated into distinct osteoclasts, their phenotypes did not vary from those of mock controls. These results suggest that RCAN1 has a limited effect on the calcineurin-NFATc1 pathway during RANKL-stimulated osteoclast differentiation.

• Journal of Ginseng Research
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• v.44 no.3
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• pp.399-404
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• 2020

Korean ginseng (Panax ginseng) is associated with a variety of therapeutic effects, including antioxidative, anti-inflammatory, vasorelaxative, antiallergic, antidiabetic, and anticancer effects. Accordingly, the use of ginseng has reached an all-time high among members of the general public. However, the safety and efficacy of ginseng in transplant recipients receiving immunosuppressant drugs have still not been elucidated. Transplantation is the most challenging and complex of surgical procedures and may require causation for the use of ginseng. In this regard, we have previously examined the safety, immunological benefits, and protective mechanisms of ginseng with respect to calcineurin inhibitor-based immunosuppression, which is the most widely used regimen in organ transplantation. Using an experimental model of calcineurin inhibitor-induced organ injury, we found that ginseng does not affect drug levels in the peripheral blood and tissue, favorably regulates immune response, and protects against calcineurin inhibitor-induced nephrotoxicity and pancreatic islet injury. On the basis of our experimental studies and a review of the related literature, we propose that ginseng may provide benefits in organ transplant recipients administered calcineurin inhibitors. Through the present review, we aimed to briefly discuss our current understanding of the therapeutic benefits of ginseng related to transplant patient survival.

• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1377-1381
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• 2014

In order to discover and develop novel signaling inhibitors from plants, a screening system was established targeting the two-component system of Cryptococcus neoformans by using the wild type and a calcineurin mutant of C. neoformans, based on the counter-regulatory action of high-osmolarity glycerol (Hog1) mitogen-activated protein kinase and the calcineurin pathways in C. neoformans. Among 10,000 plant extracts, that from Harrisonia abyssinica Oliv. exhibited the most potent inhibitory activity against C. neoformans var. grubii H99 with fludioxonil. Bioassay-guided fractionation was used to isolate two bioactive compounds from H. abyssinica, and these compounds were identified as chebulagic acid and chebulanin using spectroscopic methods. These compounds specifically inhibited the calcineurin pathway in C. neoformans. Moreover, they exhibited potent antifungal activities against various human pathogenic fungi with minimum inhibitory concentrations ranging from 0.25 to over $64{\mu}g/ml$.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.6
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• pp.311-323
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• 2023

Immunosuppressants are vital in organ transplantation including facial transplantation (FT) but are associated with persistent side effects. This review article was prepared to compare the two most used immunosuppressants, cyclosporine and tacrolimus, in terms of mechanism of action, efficacy, and safety and to assess recent trials to mitigate their side effects. PubMed and Google Scholar queries were conducted using combinations of the following search terms: "transplantation immunosuppressant," "cyclosporine," "tacrolimus," "calcineurin inhibitor (CNI)," "efficacy," "safety," "induction therapy," "maintenance therapy," and "conversion therapy." Both immunosuppressants inhibit calcineurin and effectively down-regulate cytokines. Tacrolimus may be more advantageous since it lowers the likelihood of acute rejection, has the ability to reverse allograft rejection following cyclosporine treatment, and has the potential to reinnervate nerves. Meanwhile, graft survival rates seem to be comparable for the CNIs. To avoid nephrotoxicity, various immunosuppressants other than CNIs have been studied. Despite averting nephrotoxicity, these medications show increases in acute rejection or other types of adverse effects compared to CNIs. FT has been a topic of interest for oral and maxillofacial surgeons, and the postoperative usage of immunosuppressants is crucial for the long-term prognosis of FT. As contemporary transplantation regimens incorporate novel medications along with CNIs, further research is required.