• Title/Summary/Keyword: physiology signal

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Mountain-cultivated ginseng protects against cognitive impairments in aged GPx-1 knockout mice via activation of Nrf2/ChAT/ERK signaling pathway

  • Bao Trong Nguyen;Eun-Joo Shin;Ji Hoon Jeong;Naveen Sharma;Ngoc Kim Cuong Tran;Yen Nhi Doan Nguyen;Dae-Joong Kim;Myung Bok Wie;Yi Lee;Jae Kyung Byun;Sung Kwon Ko;Seung-Yeol Nah;Hyoung-Chun Kim
    • Journal of Ginseng Research
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    • v.47 no.4
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    • pp.561-571
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    • 2023
  • Background: Escalating evidence shows that ginseng possesses an antiaging potential with cognitive enhancing activity. As mountain cultivated ginseng (MCG) is cultivated without agricultural chemicals, MCG has emerged as a popular herb medicine. However, little is known about the MCG-mediated pharmacological mechanism on brain aging. Methods: As we demonstrated that glutathione peroxidase (GPx) is important for enhancing memory function in the animal model of aging, we investigated the role of MCG as a GPx inducer using GPx-1 (a major type of GPx) knockout (KO) mice. We assessed whether MCG modulates redox and cholinergic parameters, and memory function in aged GPx-1 knockout KOmice. Results: Redox burden of aged GPx-1 KO mice was more evident than that of aged wild-type (WT) mice. Alteration of Nrf2 DNA binding activity appeared to be more evident than that of NFκB DNA binding activity in aged GPx-1 KO mice. Alteration in choline acetyltransferase (ChAT) activity was more evident than that in acetylcholine esterase activity. MCG significantly attenuated reductions in Nrf2 system and ChAT level. MCG significantly enhanced the co-localization of Nrf2-immunoreactivity and ChAT-immunoreactivity in the same cell population. Nrf2 inhibitor brusatol significantly counteracted MCG-mediated up-regulation in ChAT level and ChAT inhibition (by k252a) significantly reduced ERK phosphorylation by MCG, suggesting that MCG might require signal cascade of Nrf2/ChAT/ERK to enhance cognition. Conclusion: GPx-1 depletion might be a prerequisite for cognitive impairment in aged animals. MCG-mediated cognition enhancement might be associated with the activations of Nrf2, ChAT, and ERK signaling cascade.

The Purification and Immunogenicity of TB-14 Recombinant Protein of Mycobacterium tuberculosis (결핵균 특이 TB-14 재조합 단백질의 분리 및 세포성 면역반응에 미치는 영향)

  • Song, Ho-Yeon;Kim, Young-Hee;Kim, Chang-Hwan;Min, Young-Ki;Kim, Dae-Joong;Ko, Kwang-Kjune
    • Tuberculosis and Respiratory Diseases
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    • v.61 no.3
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    • pp.239-247
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    • 2006
  • Background: Culture filtrate proteins secreted by mycobacteria are thought to play an important role in inducing protective immunity and to develop new methods for diagnosing tuberculosis. Methods: A culture filtrate protein of M. avium that was strongly reactive with goat antiserum against M. intracellulare was constructed. Its homologous protein (TB-14) in M. tuberculosis was cloned, expressed and purified. The inductions of IFN-${\gamma}$ stimulated with $10{\mu}g$ of TB-14 recombinant protein and $10{\mu}g$ PPD were estimated by using whole bloods from seven PPD (-) subjects, seven PPD (+) healthy volunteers and nine tuberculosis patients. Results: M. avium culture filtrate protein was confirmed as a hypothetical protein that was termed contig 116. A novel 14-kDa recombinant protein (TB-14) of M. tuberculosis was composed of 148 amino acids, including 30 amino acids of the signal peptide, and it showed 78% homology with M. avium. In the PPD (+) healthy volunteers, recombinant TB-14 protein strongly induced the secretion of IFN-${\gamma}$ in whole blood cultures. Conclusion: These results suggest that TB-14 recombinant protein might play an important role in inducing cell-mediated immunity against tuberculosis. Furthermore, TB-14 protein antigen and its antiserum will be available for the development of new diagnostic tools for tuberculosis.

Effect of ATP on Calcium Channel Modulation in Rat Adrenal Chromaffin Cells (흰쥐 부신 크로마핀 세포 칼슘통로 조절에 미치는 ATP의 효과)

  • Kim, Kyung Ah;Goo, Yong Sook
    • Progress in Medical Physics
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    • v.25 no.3
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    • pp.157-166
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    • 2014
  • ATP in quantity co-stored with neurotransmitters in the secretory vesicles of neurons, by being co-released with the neurotransmitters, takes an important role to modulate the stimulus-secretion response of neurotransmitters. Here, in this study, the modulatory effect of ATP was studied in $Ca^{2+}$ channels of cultured rat adrenal chromaffin cells to investigate the physiological role of ATP in neurons. The $Ca^{2+}$ channel current was recorded in a whole-cell patch clamp configuration, which was modulated by ATP. In 10 mM $Ba^{2+}$ bath solution, ATP treatment (0.1 mM) decreased the $Ba^{2+}$ current by an average of $36{\pm}6%$ (n=8), showing a dose-dependency within the range of $10^{-4}{\sim}10^{-1}mM$. The current was recovered by ATP washout, demonstrating its reversible pattern. This current blockade effect of ATP was disinhibited by a large prepulse up to +80 mV, since the $Ba^{2+}$ current increment was larger when treated with ATP ($37{\pm}5%$, n=11) compared to the control ($25{\pm}3%$, n=12, without ATP). The $Ba^{2+}$ current was recorded with $GTP{\gamma}S$, the non-hydrolyzable GTP analogue, to determine if the blocking effect of ATP was mediated by G-protein. The $Ba^{2+}$ current decreased down to 45% of control with $GTP{\gamma}S$. With a large prepulse (+80 mV), the current increment was $34{\pm}4%$ (n=19), which $25{\pm}3%$ (n=12) under control condition (without $GTP{\gamma}S$). The $Ba^{2+}$ current waveform was well fitted to a single-exponential curve for the control, while a double-exponential curve best fitted the current signal with ATP or $GTP{\gamma}S$. In other words, a slow activation component appeared with ATP or $GTP{\gamma}S$, which suggested that both ATP and $GTP{\gamma}S$ caused slower activation of $Ca^{2+}$ channels via the same mechanism. The results suggest that ATP may block the $Ca^{2+}$ channels by G-protein and this $Ca^{2+}$ channel blocking effect of ATP is important in autocrine (or paracrine) inhibition of adrenaline secretion in chromaffin cell.

The Effect of Acetylcholine on the Intracellular $Ca^{2+}$ Increase of the Mouse Early 2-cell Embryos (생쥐 초기 2-세포 배의 세포내 칼슘 증가에 미치는 Acetylcholine의 영향)

  • Yoon S. Y.;Kang D. W.;Bae I. H.
    • Journal of Embryo Transfer
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    • v.20 no.3
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    • pp.191-200
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    • 2005
  • Many studies have shown that the development of mouse early 2-cell embryos in vitro is related with the intracellular $Ca^{2+}$ changes. In ICR strain mouse, the development of embryos arrests at early 2-cell stage, but the arrested early 2-cell embryos can be rescued by the addition of $Ca^{2+}$-related materials. Acetylcholine (ACh) increases intracellular $Ca^{2+}$ concentration ([$Ca^{2+}$]i) via the mAChR-PLC-IP3 pathway in mouse oocytes. We examined whether ACh rescues 2-cell block in mouse. In early 2-cell embryos, ACh increased [$Ca^{2+}$]i in a dose-dependent manner (p<0.001), and had an effect on rescue of 2-cell block and embryonic development. To identify the signal pathway involved in ACh-induced rescue of 2-cell block, we first applied an agonist of ACh receptor (AChR). Like ACh, carbachol increased intracellular $Ca^{2+}$ concentration ([$Ca^{2+}$]i) and atropine, an antagonist of ACh receptor, blocked the ACh-induced $Ca^{2+}$ increase. In $Ca^{2+}$-free medium, ACh also increased [$Ca^{2+}$]i, indicating that $Ca^{2+}$ increased by ACh is mainly released from the intracellular $Ca^{2+}$ store. The ACh-induced $Ca^{2+}$ increase was blocked by PLC inhibitor (U73122), ryanodine receptor (RyR) antagonist (dantrolene), and CaM KII inhibitor (KN-93), but not by IP3R antagonists (xestospongin C). These results show that ACh increases intracellular $Ca^{2+}$ concentration via mAChR/PLC/RyR, and this contributes to the rescue of 2-cell block.