• BMB Reports
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• v.38 no.6
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• pp.709-716
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• 2005

Apoptosis and necrosis are distinguished by modality primarily. Here we show an apoptosis occurred instantly, induced by $300\;{\mu}M$ W-7 ((N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride), inhibitor of calmodulin), which demonstrated necrotic modality. As early as 30 min after W-7 addition, apoptotic (sub-diploid) peak could be detected by fluorescence-activated cell sorter (FACS), “DNA ladders” began to emerge also at this time point, activity of caspase-3 elevated obviously within this period. Absence of mitochondrial membrane potential (MMP) reduction and cytochrome c, AIF (apoptosis inducing factor) release, verified that this rapid apoptosis did not proceed through mitochondria pathway. Activation of caspase-12 and changes of other endoplasmic reticulum (ER) located proteins ascertained that ER pathway mediated this necrosis-like apoptosis. Our findings suggest that it is not credible to judge apoptosis by modality. Elucidation of ER pathway is helpful to comprehend the pathology of diseases associated with ER stress, and may offer a new approach to the therapy of cancer and neurodegenerative diseases.

• Clinical and Experimental Reproductive Medicine
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• v.21 no.1
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• pp.111-119
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• 1994

"Spontaneous" hardening of the zona pellucida of mouse oocytes during in vitro culture is most likely due to cortical granules exocytosis. Thus the purpose of the present study was to determine whether the exocytosis factor is involved in spontaneous zona pellucida hardening during in vitro culture of the mouse. The results obtained form these experiments were summarized as follows; 1. When a protein synthesis inhibitor(100${\mu}g$/ml puromycin) was added to the culture medium, it did not prevent spontaneous ZPH of mouse oocyte during in vitro culture. 2. Calmodulin antagonists (trifluoperazine and chlorpromazine) and calcium channel blocker (verapamil) had no inhibitory effect in spontaneous ZPH. 3. A microtubule assembly inhibitor, colcemid had some inhibitory effect on spontaneous ZPH. 4. Treatment with a microfillament formation blocker(cytochalasin-B) at 1${\mu}g$/ml concentration, resulted in the excellent inhibitory effect on spontaneous ZPH. However cytochalasin-B did not inhibit ethanol-induced ZPH.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.1
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• pp.83-90
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• 2017

Advanced age is one of the risk factors for vascular diseases that are mainly caused by impaired nitric oxide (NO) production. It has been demonstrated that endothelial arginase constrains the activity of endothelial nitric oxide synthase (eNOS) and limits NO generation. Hence, arginase inhibition is suggested to be vasoprotective in aging. In this study, we examined the effects of intravenous injection of Piceatannol, an arginase inhibitor, on aged mice. Our results show that Piceatannol administration reduced the blood pressure in aged mice by inhibiting arginase activity, which was associated with NO production and reactive oxygen species generation. In addition, Piceatannol administration recovered $Ca^{2+}$/calmodulin-dependent protein kinase II phosphorylation, eNOS phosphorylation and eNOS dimer stability in the aged mice. The improved NO signaling was shown to be effective in attenuating the phenylephrine-dependent contractile response and in enhancing the acetylcholine-dependent vasorelaxation response in aortic rings from the aged mice. These data suggest Piceatannol as a potential treatment for vascular disease.

• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.425-431
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• 2018

Cocaine- and amphetamine-regulated transcript (CART) peptide is a widely distributed neurotransmitter expressed in the central nervous systems. Previously, several reports demonstrated that nucleus accumbal-injected CART peptide positively modulated behavioral sensitization induced by psychostimulants and regulated the mesocorticolimbic dopaminergic pathway. It is confirmed that CART peptide exerted inhibitory effect on psychostimulant-enhanced dopamine receptors signaling, $Ca^{2+}$/calmodulin-dependent kinase signaling and crucial transcription factors expression. Besides modulation of dopamine receptors-related pathways, CART peptide also exhibited elaborated interactions with other neurotransmitter receptors, such as glutamate receptors and ${\gamma}$-aminobutyric acid receptors, which further account for attribution of CART peptide to inhibition of psychostimulant-potentiated locomotor activity. Recently, CART peptide has been shown to have anxiolytic functions on the aversive mood and uncontrolled drug-seeking behaviors following drug withdrawal. Moreover, microinjection of CART peptide has been shown to have an antidepressant effect, which suggests its potential utility in the mood regulation and avoidance of depression-like behaviors. In this review, we discuss CART pathways in neural circuits and their interactions with neurotransmitters associated with psychostimulant-induced depression.

• Mycobiology
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• v.37 no.3
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• pp.161-170
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• 2009

Cryptococcus neoformans is a basidiomycete human fungal pathogen that causes meningoencephalitis in both immunocompromised and immunocompetent individuals. The ability to sense and respond to diverse extracellular signals is essential for the pathogen to infect and cause disease in the host. Four major stress-activated signaling (SAS) pathways have been characterized in C. neoformans, including the HOG (high osmolarity glycerol response), PKC/Mpk1 MAPK (mitogen-activated protein kinase), calcium-dependent calcineurin, and RAS signaling pathways. The HOG pathway in C. neoformans not only controls responses to diverse environmental stresses, including osmotic shock, UV irradiation, oxidative stress, heavy metal stress, antifungal drugs, toxic metabolites, and high temperature, but also regulates ergosterol biosynthesis. The PKC(protein kinase C)/Mpk1 pathway in C. neoformans is involved in a variety of stress responses, including osmotic, oxidative, and nitrosative stresses and breaches of cell wall integrity. The $Ca^{2+}$/calmodulin- and Ras-signaling pathways also play critical roles in adaptation to certain environmental stresses, such as high temperature and sexual differentiation. Perturbation of the SAS pathways not only impairs the ability of C. neoformans to resist a variety of environmental stresses during host infection, but also affects production of virulence factors, such as capsule and melanin. A drug(s) capable of targeting signaling components of the SAS pathway will be effective for treatment of cryptococcosis.

• The Korean Journal of Physiology
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• v.20 no.2
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• pp.236-248
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• 1986

Alterations of renin-angiotensin system have been suggested as one of the mechanisms increasing arterial blood pressure in experimental and clinical hypertension. But the exact nature of high blood pressure in the early and late phase of renal hypertension is still controversial. To clarify the nature of renin release in both unclipped and clipped kidney of two kidney one clip Goldblatt lypertensive rat, experiments have been done in kidney slices, which were obtained from the rats of 3 and 7 days of operation. Basal rate of renin release was suppressed in unclipped kidney slices compared to clipped kidney Norepinephrine increased renin release from unclipped kidney slices, but not from clipped kidney slices. Suppressions by angiotensin Il and arginine vasopressin of renin release were attenuated in the clipped kidney slices compared to unclipped and sham-operated kidney slices. Increases by verapamil and trifluoperazine of renin release were attenuated in the clipped kidney slices compared to unclipped and sham-operated kidney slices. These results suggest that the negative feedback control mechanism of the renin-angiotensin system by angiotensin Il and arginine vasopressin is attenuated in the clipped kidney of two kidney one clip Goldblatt hypertensive rat, and that one of the altered mechanisms may be caused by certain regulatory changes of intracellular calcium and/or calcium-calmodulin complex in the juxtaglomerular cells.

• Mycobiology
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• v.49 no.6
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• pp.534-550
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• 2021

During a survey of fungal diversity associated with insects, mud, soil, and freshwater niches in different areas in Korea, nine interesting fungal strains were isolated. Based on their morphological characteristics and molecular phylogeny analyses, using a combined data set of b-tubulin (BenA), calmodulin (CaM), and second largest subunit of RNA polymerase (RPB2) sequences, the strains CNUFC AM-44, CNUFC JCW3-4, CNUFC S708, CNUFC WT202, CNUFC AS1-29, CNUFC JCW3-5, CNUFC JDP37, and CNUFC JDP62 were identified as Aspergillus alabamensis, A. floridensis, A. subversicolor, Penicillium flavigenum, P. laevigatum, P. lenticrescens, Talaromyces adpressus, and T. beijingensis, respectively. The strain CNUFC JT1301 belongs to series Westlingiorum in section Citrina and is phylogenetically related to P. manginii. However, slow growth when cultivated on CYA, MEA, CREA is observed and the property can be used to easily distinguish the new species from these species. Additionally, P. manginii is known to produce sclerotia, while CNUFC JT1301 strain does not. Herein, the new fungal species is proposed as P. aquadulcis sp. nov. Eight species, A. alabamensis, A. floridensis, A. subversicolor, P. flavigenum, P. laevigatum, P. lenticrescens, T. adpressus, and T. beijingensis, have not been previously reported in Korea. The present study expands the known distribution of fungal species belonging to the families Aspergillaceae and Trichocomaceae in Korea.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.347-355
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• 2022

A fungal isolate belonging to the phylum Ascomycota was isolated and identified as Talaromyces veerkampii in 2017 during a survey of fungal diversity in field soils in Korea. This fungal isolate was identified and described based on macro- and micromorphological and molecular characterization. The identification was also based on partial 18S-ITS1-5.8S-ITS2-28S rDNA and calmodulin (CaM)-encoding gene sequencing data. Talaromyces veerkampii has not been previously reported in Korea. Thus, we report here a newly discovered species from soil in Korea along with its morphological and molecular characteristics.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.491-504
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• 2023

To explore fungal diversity in orchard soil where fire-blighted apple trees are buried, we collected soil samples from apple orchards in Chungju, Korea. Fungal isolates were obtained from DG18 agar and identified at the species level based on morphological features and phylogenetic analyses. The colony characteristics and microstructures were examined using a light microscope and a scanning electron microscope after culturing on potato dextrose agar (PDA), malt extract agar (MEA), Czapek yeast agar (CYA), and oatmeal agar (OA) The PCR-amplified products of the ITS1-5.8S-ITS2 region and 28S large subunit of the nuclear ribosomal RNA gene, as well as partial sequences of the β-tubulin, calmodulin, and translation elongation factor 1-α genes were sequenced and analyzed phylogenetically. Seven previously unknown fungal species were explored in Korea. All samples, including Aspergillus aureolatus, Botryotrichum atrogriseum, Dactylonectria novozelandica, Fusarium denticulatum, Paecilomyces tabacinus, Sarcopodium tibetense and Talaromyces stollii, had ascomycetes. Herein, we report their descriptions and features.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.479-487
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• 2000

Several recent studies demonstrate that receptor-mediated cAMP (adenosine 3',5'-monophosphate) production evokes marked change in magnesium ($Mg^{2+}$) homeostasis. The effects of dimaprit or/and phosphodiesterase (PDE) inhibitors on the $Mg^{2+}$ release from perfused guinea pig heart and collagenase-dispersed myocytes was studied to clarify an association of $H_2-histaminergic$ receptor-mediated $Mg^{2+}$ regulation with intracellular cAMP-degradation system. $Mg^{2+}$ efflux was stimulated in perfused hearts and myocytes by IBMX (3-isobutyl-1-methylxanthine), a calmodulin-sensitive PDE inhibitor, but not by RO 20-1724(4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone) or papaverine, cAMP-specific PDE inhibitors. $Mg^{2+}$ efflux was also be induced by dimaprit, a H-2-agonist. $Mg^{2+}$ effluxes induced by dimaprit were augmented by the presence of the PDE inhibitors. The augmentation of dimaprit-induced $Mg^{2+}$ effluxes by the PDE inhibitors were inhibited by ranitidine, a $H_2-antagonist$, and imipramine, a $Na^{+}-Mg^{2+}$ exchange inhibitor, in perfused hearts and myocytes and were also inhibited by amiloride in perfused hearts. These results suggest that the $H_2$-stimulated $Mg^{2+}$ effluxes from guinea pig heart can be regulated by the cytosolic nonspecific-dependent PDE systems and that it is induced by the $Na^{+}-Mg^{2+}$ exchanger stimulation.