• The Korean Journal of Physiology and Pharmacology
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• 제20권1호
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• pp.101-109
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• 2016

Reducing $[Mg^{2+}]_o$ to 0.1 mM can evoke repetitive $[Ca^{2+}]_i$ spikes and seizure activity, which induces neuronal cell death in a process called excitotoxicity. We examined the issue of whether cultured rat hippocampal neurons preconditioned by a brief exposure to 0.1 mM $[Mg^{2+}]_o$ are rendered resistant to excitotoxicity induced by a subsequent prolonged exposure and whether $Ca^{2+}$ spikes are involved in this process. Preconditioning by an exposure to 0.1 mM $[Mg^{2+}]_o$ for 5 min inhibited significantly subsequent 24 h exposure-induced cell death 24 h later (tolerance). Such tolerance was prevented by both the NMDA receptor antagonist D-AP5 and the L-type $Ca^{2+}$ channel antagonist nimodipine, which blocked 0.1 mM $[Mg^{2+}]_o$-induced $[Ca^{2+}]_i$ spikes. The AMPA receptor antagonist NBQX significantly inhibited both the tolerance and the $[Ca^{2+}]_i$ spikes. The intracellular $Ca^{2+}$ chelator BAPTA-AM significantly prevented the tolerance. The nonspecific PKC inhibitor staurosporin inhibited the tolerance without affecting the $[Ca^{2+}]_i$ spikes. While $G{\ddot{o}}6976$, a specific inhibitor of $PKC{\alpha}$ had no effect on the tolerance, both the $PKC{\varepsilon}$ translocation inhibitor and the $PKC{\zeta}$ pseudosubstrate inhibitor significantly inhibited the tolerance without affecting the $[Ca^{2+}]_i$ spikes. Furthermore, JAK-2 inhibitor AG490, MAPK kinase inhibitor PD98059, and CaMKII inhibitor KN-62 inhibited the tolerance, but PI-3 kinase inhibitor LY294,002 did not. The protein synthesis inhibitor cycloheximide significantly inhibited the tolerance. Collectively, these results suggest that low $[Mg^{2+}]_o$ preconditioning induced excitotoxic tolerance was directly or indirectly mediated through the $[Ca^{2+}]_i$ spike-induced activation of $PKC{\varepsilon}$ and $PKC{\xi}$, JAK-2, MAPK kinase, CaMKII and the de novo synthesis of proteins.

• 대한한의학회지
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• 제25권2호
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• pp.127-137
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• 2004

Objectives : The purpose of this investigation was to evaluate the effects of Sohaphyang-won (SH) on the alteration in gene expression in a hypoxia model using cultured rat cortical cells. Methods : E18 rat cortical cells were grown in neurobasal medium containing B27 supplement. On 12 DIV, SH was added ($20\mu\textrm{g}/ml$) to the culture media for 24 hrs. On 14 DIV, cells were given a hypoxic insult (2% O2/5% CO2, $37^{\circ}C$, 3 hrs), returned to normoxia and cultured for another 24 hrs. Total RNA was prepared from SH-untreated (control) and -treated cultures and alteration in gene expression was analyzed by microarray using rat 5K-TwinChips. Results : Effects on some of the genes whose functions are implicated in neural viability are as follows: 1) For most of the genes altered in expression, the global M values were between -05 to +0.5, Among these, 1517 genes were increased in their expression by more than global M +0.1, while 1480 genes were decreased by more than global M -0.1. 2) The expression of apoptosis-related genes such as Bad (global M =0.35), tumor protein p53 (T53) (global M =0.28) were increased, while v-akt murine thymoma viral oncogene homolog 1 (Akt1) was decreased. 3) The expression of hemoglobin alpha 1 (probably neuroglobin) was increased by about 3.2-fold (global M =1.7). 4) The expression of antioxidation-related catalase gene was increased (global M =0.26). 5) The expression of PKCzeta (prkcz), an upstream kinase of MAPK, was increased (global M =0.29). 6) The expression of retinoic acid receptor alpha (RAR), which may regulate transcription in hypoxic stress, was increased (global M =10.27). Conclusions : In summary, the microarray data suggest that SH doesn't increase the expression of oxygen capture-, anti-oxidation- and 'response to stress' -related genes but decreases some anti-apoptosis genes which would help protect the hypoxic cells from apoptosis.

• 한국잠사곤충학회지
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• 제51권2호
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• pp.99-106
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• 2013

본 연구는 8주간의 사다리를 이용한 점진적 저항성 운동과 더불어 오디분말, 오디추출물, 누에분말의 섭취가 흰쥐의 골격근에서 androgen receptor(AR) mRNA와 myogenic regulatory factors(MRFs)의 발현에 효과가 있는지 확인하고자 하였다. 6주령의 Rat 50두를 분양받아 일주일간 순화기간을 거친 후 군간 체중을 고르게 분리하고 시료 투여 및 저항성 운동 여부에 따라 대조군, 운동군, 오디분말 운동군, 오디추출물 운동군, 누에분말 운동군으로 설정하였다. 시료 투여집단은 고형사료에 각각의 시료가 배합된 사료를 자유롭게 섭취하도록 하였다. 저항성 운동 방법은 1주일간 주당 3일, 1일 5회씩 부하 없이 맨몸 사다리 운동을 거친 후 7주간 주당 2일, 1일 10회씩 점진적인 과부하 하에서 실시하였다. 8주간 저항성 운동이 끝난 후 오른쪽 뒷다리에서 장무지굴근을 적출한 후 RNA 추출 및 cDNA를 합성하여 $-20^{\circ}C$에 보관 후 실험에 사용하였다. AR mRNA와 MRFs를 특이적으로 검출하도록 디자인된 시발체와 탐색자를 구입하여 housekeeping 유전자인 18s rRNA와 함께 Real Time PCR을 이용하여 증폭하였다. 18s rRNA를 이용하여 흰쥐의 장무지굴근에서 AR mRNA와 MRFs를 $2^{-{\Delta}{\Delta}Ct}$법을 통해 상대정량하여 골격근 내 발현 정도를 배수변화로 비교하였다. 실험 결과 사다리 운동과 시료 섭취는 흰쥐 골격근에서 AR mRNA의 발현을 유의하게 증가시키는 것으로 나타났다. 대조군과 비교하여 모든 저항성 운동 집단에서 통계적으로 유의한 차이를 보였으며 운동군에서 $4.04{\pm}1.12$, 오디분말 운동군에서 $5.23{\pm}0.56$, 오디추출물 운동군에서 $6.24{\pm}1.85$, 누에분말 운동군에서 $9.68{\pm}0.82$배를 나타내었다. 운동군과 비교하여 오디추출물 운동군과 누에분말 운동군에서 유의한 차이를 나타냈으며 오디분말 운동군의 경우 운동군과 비교하여 유의한 차이를 나타내지 않았지만 대조군과 비교하여 유의한 차이를 나타내었다. MyoD mRNA의 경우 대조군과 비교하여 운동군에서 $2.19{\pm}0.27$, 오디분말 운동군에서 $6.04{\pm}0.48$, 오디추출물 운동군에서 $4.32{\pm}1.59$, 누에분말 운동군에서 $8.11{\pm}0.57$배를 나타내었다. 운동군과 비교하여 모든 시료 섭취 집단에서 유의한 차이를 나타내었다. Myogenin mRNA의 경우 대조군과 비교하여 운동군에서 $2.70{\pm}0.57$, 오디분말 운동군에서 $4.11{\pm}0.42$, 오디추출물 운동군에서 $4.13{\pm}0.45$, 누에분말 운동군에서 $6.50{\pm}0.61$배를 나타내었다. 대조군과 비교하여 모든 저항성 운동군에서 유의한 차이를 나타냈으며 운동군과 비교하여 모든 시료 섭취 집단에서 유의한 차이를 나타내었다. 본 실험을 통해 오디와 누에의 섭취는 저항성 운동에 따른 수컷 흰쥐의 골격근에서 근육 관련 유전자인 AR mRNA와 MRFs의 발현에 긍정적인 영향을 미치며 추후 근육 증가를 목적으로 한 운동보조제 개발을 위한 기초 자료가 될 수 있을 것으로 판단된다.

• 한국식품영양과학회지
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• 제43권1호
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• pp.24-29
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• 2014

본 연구는 구기자와 구기엽 추출물이 난소를 절제한 흰쥐의 체중 증가, 골밀도, 에스트로겐 수용체의 발현에 미치는 영향을 밝히고자 시행하였다. 실험군은 흰쥐 24마리를 가장수술군(Sham군), 난소를 절제한 대조군(OVX군), 난소절제 후 구기자 추출액을 투여한 군(LCF군), 난소절제 후 구기엽 추출액을 투여한 군(LCL군)으로 구분하였다. 8주 후 난소를 절제한 OVX군($330{\pm}5.39g$), LCF군($315{\pm}2.99g$) 및 LCL군($318{\pm}2.06g$)의 체중은 Sham군($281{\pm}1.71g$)에 비하여 증가하였다. 혈청 osteocalcin 활성은 OVX군($107{\pm}3.52ng/mL$)에 비하여 LCF군($444.6{\pm}26.9ng/mL$)과 LCL군($407{\pm}18.9ng/mL$)에서 증가하였다. Alkaline phosphatase의 활성은 OVX군($95{\pm}2.9U/L$)에 비하여 LCF군($108{\pm}2.7U/L$)과 LCL군($407{\pm}18.9ng/mL$)에서 증가하였다. 8주 후 넙다리뼈를 실체현미경으로 관찰한 결과 뼈 기질밀도는 난소절제군에서 감소하였으나, 구기자와 구기엽을 추출액을 투여한 군에서는 뚜렷이 회복되었다. 에스트로겐 수용체의 mRNA 발현은 OVX군에서는 거의 발현되지 않았으나, LCF군과 LCL군에서 뚜렷이 증가하였다. 이상의 결과로 보아 구기자와 구기엽 물추출물이 난소절제에 의하여 유발된 흰쥐의 뼈 기질 회복 또는 손실 지연에 효과가 있다고 할 수 있을 것이다.

• 약학회지
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• 제32권6호
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• pp.402-414
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• 1988

In order to clarify the receptor types and mechanisms underlying the positive inotropic effect of dopamine on the mammalian ventricular myocardium, the action potential, its first derivatives and isometric contraction of the rabbit papillary muscle were recorded using a force transducer and glass capillary microelectrodes filled with 3M KCl. The results were as follows; (1) In normal Tyrode solution, the contractile force was increased and duration of action potential was shortened with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (2) The dose-response curve was markedly shifted to the right by pretreatment with reserpine (5mg/kg i.p., 24hrs prior to the experiment). (3) In 19mM $K^+-Tyrode$ solution, the duration of action potential, maximum rate of rise (V_{max}) of action potential and overshoot were significantly increased with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (4) The inotropic effect of dopamine on the rabbit papillary muscle pretreated with reserpine was antagonized by atenolol ($10^{-6}M$), but not by phentolamine ($3{\times}10^{-6}M$). (5) In rabbit papillary muscle partially depolarized by 19mM $K^+-Tyrode$ solution, slow electrical response (calcium mediated action potential) as well as contraction were restored by dopamine ($10^{-4}M$); this restoration was blocked by calcium antagonists ($3{\times}10^{-5}M$ $LaCl_3{\cdot}6H_2O$, $3{\times}10^{-6}M$ diltiazem) or ${\beta}-adrenoceptor$ antagonist ($3{\times}10^{-6}M$ atenolol), but not affected by ${\alpha}-adrenoceptor$ antagonist ($10^{-5}M$ phentolamine, $3{\times}10^{-6}M$ yohimbine) or vascular dopaminergic receptor antagonist ($10^{-5}M$ haloperidol). The above results may be interpreted as that the positive inotropic effect of dopamine through both direct and indirect action are caused by increase in slow inward current ($Ca^{2+}$ influx into themyocardial cell), and the direct action is mainly due to the stimulation of ${\beta}-adrenoceptors$ in the rabbit papillary muscle.

• The Korean Journal of Physiology and Pharmacology
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• 제15권3호
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• pp.179-187
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• 2011

Regulation of B cell receptor (BCR)-induced $Ca^{2+}$ signaling by CD40 co-stimulation was compared in long-term BCR-stimulated immature (WEHI-231) and mature (Bal-17) B cells. In response to long-term pre-stimulation of immature WEHI-231 cells to ${\alpha}$-IgM antibody (0.5~48 hr), the initial transient decrease in BCR-induced $[Ca^{2+}]_i$ was followed by spontaneous recovery to control level within 24 hr. The recovery of $Ca^{2+}$ signaling in WEHI-231 cells was not due to restoration of internalized receptor but instead to an increase in the levels of $PLC{\gamma}2$ and $IP_3R-3$. CD40 co-stimulation of WEHI-231 cells prevented BCR-induced cell cycle arrest and apoptosis, and it strongly inhibited the recovery of BCR-induced $Ca^{2+}$ signaling. CD40 co-stimulation also enhanced BCR internalization and reduced expression of $PLC{\gamma}2$ and $IP_3R-3$. Pre-treatment of WEHI-231 cells with the antioxidant N-acetyl-L-cysteine (NAC) strongly inhibited CD40-mediated prevention of the recovery of $Ca^{2+}$ signaling. In contrast to immature WEHI-231 cells, identical long-term ${\alpha}$-IgM pre-stimulation of mature Bal-17 cells abolished the increase in BCR-induced $[Ca^{2+}]_i$, regardless of CD40 co-stimulation. These results suggest that CD40-mediated signaling prevents antigen-induced cell cycle arrest and apoptosis of immature B cells through inhibition of sustained BCR-induced $Ca^{2+}$ signaling.

• The Korean Journal of Physiology and Pharmacology
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• 제2권2호
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• pp.241-249
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• 1998

Platelet-activating factor(PAF) enhanced interleukin-1(IL-1) activity by the interaction with a specific receptor in rat alveolar macrophages. In this study, we investigated the role of endogenous arachidonate metabolites and intracellular calcium mobilization in the PAF-induced IL-1 activity. Alveolar macrophages were preincubated with 5-lipoxygenase and cyclooxygenase inhibitors 30 min before the addition of PAF and lipopolysaccharide(LPS). After 24h culture, IL-1 activity was measured in the supernate of sample using the thymocyte proliferation assay. Inhibition of 5-lipoxygenase by nordihydroguaiaretic acid and AA-861 completely blocked the PAF-induced enhancement of IL-1 activity with $IC_{50}\;of\;2\;{\mu}M\;and\;5\;{\mu}M$, respectively. In contrast, the inhibition of cyclooxygenase pathway by indomethacin and ibuprofen resulted in the potentiation in PAF-induced IL-1 activity with maximal effect at $1\;{\mu}M\;and\;5\;{\mu}M$, respectively. In addition, leukotriene $B_4$ and prostaglandin $E_2$ production were observed in PAF-stimulated alveolar macrophage culture. As could be expected, 5-lipoxygenase and cyclooxygenase inhibitors abolished PAF- stimulated leukotriene $B_4$ and prostaglandin $E_2$ production, respectively. The effects of PAF on intracellular calcium mobilization in alveolar macrophages were evaluated using the calcium-sensitive dye fura-2 at the single cell level. PAF at any dose between $10^{-16}\;and\;10^{-8}$ M did not increase intracellular calcium. Furthermore, there was no effective change of intracellular calcium level when PAF was added to alveolar macrophages in the presence of LPS or LPS+LTB4, and 4, 24 and 48h after treatment of these stimulants. Together, the results indicate that IL-1 activity induced by PAF is differently regulated through subsequent induction of endogenous 5-lipoxygenase and cyclooxygenase pathways, but not dependent on calcium signalling pathway.

• Journal of Interdisciplinary Genomics
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• 제4권1호
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• pp.1-6
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• 2022

Purpose: Mastectomy is performed as a surgical treatment for patients with breast cancer who have the BRCA 1/2 mutation. In this study, we have reported the trends in Korea for both immediate breast reconstruction and prophylactic mastectomy. Methods: This retrospective study was conducted from 2019 to 2021. Both skin-sparing mastectomy and immediate implant-based breast reconstruction with prepectoral and/or subpectoral techniques were performed in five patients with BRCA 1/2 mutations. Data on age; body mass index; cancer stage; BRCA 1/2 mutation; estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression; diagnosis; and complications were collected. Results: The average (±standard deviation [SD]) age was 44.0±6.48 years old; BMI 24.5±2.25 kg/m²; and breast volumes were 365.8±70.34 and 382.4±96.33 cc for right and left ones, respectively. The BRCA 1 and 2 were diagnosed in four and one patients, respectively. The estrogen and progesterone receptors and human epidermal growth factor receptor 2 were detected in one (20%), one (20%), and three (60%) patients, respectively. The applied implant-based breast reconstruction techniques for ten breasts were subpectoral technique (n=7, 70%) and prepectoral technique (n=3, 30%). For the cancer stage, those with I, II, and III stages were one (20%), two (40%), and one (20%), respectively. There were no major complications such as Infection, seroma. Conclusion: When mastectomy is performed as surgical treatment in BRCA 1/2 mutation positive breast cancer patients, it is possible to obtain a better outcome with both implant-based breast reconstruction and different circumstances between breast cancer and contralateral breast.

• Molecules and Cells
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• 제24권3호
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• pp.372-377
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• 2007

The orphan nuclear receptor, SF-1, plays a pivotal role in the development and differentiation of the endocrine and reproductive systems, and also regulates the transcription of a host of genes, including those encoding several steroidogenic enzymes and gonadotropins. We found that a previously unidentified repressor, EID-1, is an SF-1-interacting protein that inhibits the transactivation of SF-1. A transient transfection assay revealed that EID-1 inhibits SF-1, but not LRH-1, $ERR{\gamma}$, or mCAR. Using the yeast two hybrid and GST pull-down assays, we determined that EID-1 interacted strongly with SF-1. In addition, it colocalized with SF-1 in mammalian cells and interacted specifically with the AF-2 domain of SF-1, competing with SRC-1 to inhibit SF-1 transactivation. EID-1 is expressed in the mouse testis, and its expression decreases during testis development. The results of the present study suggest that EID-1 can act as a repressor, regulating the function of SF-1.

• Biomolecules & Therapeutics
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• 제24권2호
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• pp.191-198
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• 2016

The vitamin D receptor (VDR) is a member of the nuclear receptor (NR) superfamily. The VDR binds to active vitamin $D_3$ metabolites, which stimulates downstream transduction signaling involved in various physiological activities such as calcium homeostasis, bone mineralization, and cell differentiation. Quercetin is a widely distributed flavonoid in nature that is known to enhance transactivation of VDR target genes. However, the detailed molecular mechanism underlying VDR activation by quercetin is not well understood. We first demonstrated the interaction between quercetin and the VDR at the molecular level by using fluorescence quenching and saturation transfer difference (STD) NMR experiments. The dissociation constant ($K_d$) of quercetin and the VDR was $21.15{\pm}4.31{\mu}M$, and the mapping of quercetin subsites for VDR binding was performed using STD-NMR. The binding mode of quercetin was investigated by a docking study combined with molecular dynamics (MD) simulation. Quercetin might serve as a scaffold for the development of VDR modulators with selective biological activities.