• Title/Summary/Keyword: p-Akt

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Antiapoptotic Effect of Paricalcitol in Gentamicin-induced Kidney Injury

  • Suh, Sang Heon;Lee, Ko Eun;Park, Jeong Woo;Kim, In Jin;Kim, Ok;Kim, Chang Seong;Choi, Joon Seok;Bae, Eun Hui;Ma, Seong Kwon;Lee, Jong Un;Kim, Soo Wan
    • The Korean Journal of Physiology and Pharmacology
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    • v.17 no.5
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    • pp.435-440
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    • 2013
  • While the anti-apoptotic effect of paricalcitol has been demonstrated in various animal models, it is not yet clear whether paricalcitol attenuates the apoptosis in gentamicin (GM)-induced kidney injury. We investigated the effect of paricalcitol on apoptotic pathways in rat kidneys damaged by GM. Rats were randomly divided into three groups: 1) Control group (n=8), where only vehicle was delivered, 2) GM group (n=10), where rats were treated with GM (150 mg/kg/day) for 7 days, 3) PARI group (n=10), where rats were co-treated with paricalcitol (0.2 ${\mu}g/kg/day$) and GM for 7 days. Paricalcitol attenuated renal dysfunction by GM administration in biochemical profiles. In terminal deoxynucleotidyl transferase dUTP nick end labeling staining, increased apoptosis was observed in GM group, which was reversed by paricalcitol co-treatment. Immunoblotting using protein samples from rat cortex/outer stripe of outer medulla showed increased Bax/Bcl-2 ratio and cleaved form of caspase-3 in GM group, both of which were reversed by paricalcitol. The phosphorylated Jun-N-terminal kinase (JNK) expression was increase in GM, which was counteracted by paricalcitol. The protein expression of p-Akt and nitro-tyrosine was also enhanced in GM-treated rats compared with control rats, which was reversed by paricalcitol co-treatment. Paricalcitol protects GM-induced renal injury by antiapoptotic mechanisms, including inhibition of intrinsic apoptosis pathway and JNK.

Safflower Seed Oil and Its Active Compound Acacetin Inhibit UVB-Induced Skin Photoaging

  • Jeong, Eun Hee;Yang, Hee;Kim, Jong-Eun;Lee, Ki Won
    • Journal of Microbiology and Biotechnology
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    • v.30 no.10
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    • pp.1567-1573
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    • 2020
  • Ultraviolet (UV) is one of the major factors harmful to skin health. Irradiation with ultraviolet accelerates the decline of skin function, causing the skin to have deep wrinkles, dryness, decreased procollagen production, and degradation of collagen. Novel materials are needed to prevent the aging of the skin by blocking the effects of UV. Safflower seed oil (Charthamus tinctorius L., SSO) contains significantly high levels of unsaturated fatty acids and phytochemicals. SSO has been traditionally used in China, Japan, and Korea to improve skin and hair. Our objective in this study was to determine the effect of SSO and its active compound acacetin on UVB-induced skin photoaging in HaCaT cells and human dermal fibroblasts (HDF). SSO inhibited UVB-induced matrix metalloproteinase-1 (MMP-1) at both protein and mRNA levels in HaCaT cells and HDF. MMP-1 is known to play important roles in collagen degradation and wrinkle formation. Acacetin, a type of flavonoid, is present in SSO. Similar to SSO, acacetin also inhibited UVB-induced MMP-1 protein and mRNA levels in HaCaT cells and HDF. MMP-1 mRNA is primarily regulated by the mitogen-activated kinase (MAPK) signaling pathway. Acacetin regulated the phosphorylation of JNK1/2 and c-jun, but did not inhibit the phosphorylation of ERK1/2, p38 and AKT. Taken together, these results indicate that SSO and its active compound acacetin can prevent UVB-induced MMP-1 expression, which leads to skin photoaging, and may therefore have therapeutic potential as an anti-wrinkle agent to improve skin health.

Morus alba Accumulates Reactive Oxygen Species to Initiate Apoptosis via FOXO-Caspase 3-Dependent Pathway in Neuroblastoma Cells

  • Kwon, Young Hwi;Bishayee, Kausik;Rahman, Md. Ataur;Hong, Jae Seung;Lim, Soon-Sung;Huh, Sung-Oh
    • Molecules and Cells
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    • v.38 no.7
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    • pp.630-637
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    • 2015
  • Morus alba root extract (MARE) has been used to treat hyperglycaemic conditions in oriental medicine. Here, we studied whether MARE possesses a cytotoxic effect on neuroblastoma. To check the cytotoxicity generated by MARE was whether relatively higher against the cancer cells rather than normal cells, we chose a neuroblastoma cell line (B103) and a normal cell line (Rat-2). A CCK assay revealed that MARE ($10{\mu}g/ml$) reduced cell viability to approximately 60% compared to an untreated control in B103 cells. But in Rat-2 cells, MARE induced relatively lower cytotoxicity. To investigate the mechanisms underlying the cytotoxic effect of MARE, we used flow cytometry combined with immunoblot analyses. We found that MARE-treatment could accumulate ROS and depolarize mitochondria membrane potential of B103 cells. Further treatment with MARE in B103 cells also could damage DNA and induce apoptosis. An expression study of p-Akt also suggested that there was a reduction in cellular proliferation and transcription along with the process of apoptosis, which was further evidenced by an increase in Bax and cleaved-caspase 3 activity. Together, our findings suggest that MARE produces more cytotoxicity in cancer cells while having a relatively attenuated effect on normal cells. As such, MARE may be a safer option in cancer therapeutics, and it also shows potential for the patients with symptoms of hyperglycemia and cancer.

Inhibitory Effects of Yongbu-tang on Osteoclast Differentiation and Bone Resorption (용부탕의 파골세포 분화 억제와 골 흡수 억제효과)

  • Lee, Jeong Ju;Jo, So Hyun;Park, Min Cheol;Jo, Eun Heui
    • Journal of Acupuncture Research
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    • v.32 no.3
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    • pp.27-40
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    • 2015
  • Objectives : This study was performed to evaluate the effects of water extract of Cervi Parvum Cornu(CPC), Aconiti Lateralis Radix Preparata(ALR), and Yongbu-tang(YBT) on suppression of the receptor activator of nuclear factor kappa-B ligand(RANKL)-induced osteoclast differentiation and bone resorption. Methods : The effects of CPC, ALR, YBT extracts on osteoclast differentiation were determined by culture of bone marrow macrophage(BMM). The mRNA expression levels of the nuclear factor of activated T-cells cytoplasmic 1(NFATc1), c-Fos and tartrate-resistant acid phosphatase(TRAP) in BMMs were analyzed by reverse transcriptase polymerase chain reaction(RT-PCR). Similarly, the protein expression levels of NFATc1, c-Fos, mitogen-activated protein kinase(MAPK)s and ${\beta}$-actin in cell lysates were measured by western blotting. In addition, effects of CPC, ALR and YBT extracts were determined by means of Lipopolysaccharide(LPS)-induced bone-loss with mice. Results : CPC, ALR and YBT extracts showed remarkable inhibition on RANKL-induced osteoclast differentiation without cytotoxicity. CPC and ALR extracts significantly reduced the protein expression level of NFATc1. YBT extract significantly reduced the mRNA expression levels of c-Fos, NFATc1 and the protein expression levels of c-Fos, NFATc1, AKT, p38, c-Jun N-terminal kinase(JNK). Further, YBT extract suppressed degradation of$ I-{\kappa}B$. And ALR extract significantly restored the bone erosion by LPS treatment in mice. Conclusions : YBT extract showed more remarkable inhibition on osteoclast differentiation than CPC and ALR extracts in vitro. ALR extract showed remarkable inhibition on bone resorption in vivo. Thus, YBT extract can be a useful treatment for bone-loss diseases such as osteoporosis.

NSAID Activated Gene (NAG-1), a Modulator of Tumorigenesis

  • Eling, Thomas E.;Baek, Seung-Joon;Shim, Min-sub;Lee, Chang-Ho
    • BMB Reports
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    • v.39 no.6
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    • pp.649-655
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    • 2006
  • The NSAID activated gene (NAG-1), a member of the TGF-$\beta$ superfamily, is involved in tumor progression and development. The over-expression of NAG-1 in cancer cells results in growth arrest and increase in apoptosis, suggesting that NAG-1 has anti-tumorigenic activity. This conclusion is further supported by results of experiments with transgenic mice that ubiquitously express human NAG-1. These transgenic mice are resistant to the development of intestinal tumors following treatment with azoxymethane or by introduction of a mutant APC gene. In contrast, other data suggest a pro-tumorigenic role for NAG-1, for example, high expression of NAG-1 is frequently observed in tumors. NAG-1 may be like other members of the TGF-$\beta$ superfamily, acting as a tumor suppressor in the early stages, but acting pro-tumorigenic at the later stages of tumor progression. The expression of NAG-1 can be increased by treatment with drugs and chemicals documented to prevent tumor formation and development. Most notable is the increase in NAG-1 expression by the inhibitors of cyclooxygenases that prevent human colorectal cancer development. The regulation of NAG-1 is complex, but these agents act through either p53 or EGR-1 related pathways. In addition, an increase in NAG-1 is observed in inhibition of the AKT/GSK-$3{\beta}$ pathway, suggesting NAG-1 alters cell survival. Thus, NAG-1 expression is regulated by tumor suppressor pathways and appears to modulate tumor progression.

Enhanced Chondrogenic Differentiation of Human Adipose-derived Stem Cells with Inverse Opal Scaffolds (역오팔 구조 지지체를 이용한 인간 지방 유래 줄기 세포의 연골 분화 촉진)

  • Bhang, Suk Ho;Yu, Taekyung
    • Korean Chemical Engineering Research
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    • v.51 no.6
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    • pp.727-732
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    • 2013
  • In this report, we present an inverse opal scaffold that can enhance the chondrogenic differentiation of human adipose-derived stem cells (hADSCs) without drug, gene, or cytokine supplement. Inverse opal scaffolds based on poly(D,L-lactide-co-glycolide) were formed with uniform $200{\mu}m$ pores. Due to uniform pore sizes and well-controlled interconnectivity of inverse opal scaffold, hADSCs were allowed to distribute homogeneously throughout the scaffolds. As a result, high cell density culture with scaffold was possible. Since the hADSCs cultured in inverse opal scaffolds were subjected to limited supplies of oxygen and nutrients, these cells were naturally preconditioned to a hypoxic environment that stimulated the up-regulation of hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$). As a result, apoptotic activity of hADSCs until 3 weeks after initial cell seeding was significantly reduced and chondrogenic differentiation related molecular signal cascades were up regulated (transforming growth factor-beta, phosphorylated AKT, and phosphorylated p38 expression). In contrast, hADSCs cultured with small and non-uniform porous scaffolds showed significantly increased apoptotic activity with decreased chondrogenic differentiation. Taken together, inverse opal scaffold could potentially be used as an effective tool for improving chondrogenesis using stem cells.

(E)-3-(3-methoxyphenyl)-1-(2-pyrrolyl)-2-propenone displays suppression of inflammatory responses via inhibition of Src, Syk, and NF-κB

  • Kim, Yong;Jeong, Eun Jeong;Han Lee, In-Sook;Kim, Mi-Yeon;Cho, Jae Youl
    • The Korean Journal of Physiology and Pharmacology
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    • v.20 no.1
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    • pp.91-99
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    • 2016
  • (E)-3-(3-methoxyphenyl)-1-(2-pyrrolyl)-2-propenone (MPP) is an aldol condensation product resulting from pyrrole-2-carbaldehyde and m- and p- substituted acetophenones. However, its biological activity has not yet been evaluated. Since it has been reported that some propenone-type compounds display anti-inflammatory activity, we investigated whether MPP could negatively modulate inflammatory responses. To do this, we employed lipopolysaccharide (LPS)-stimulated macrophage-like RAW264.7 cells and examined the inhibitory levels of nitric oxide (NO) production and transcriptional activation, as well as the target proteins involved in the inflammatory signaling cascade. Interestingly, MPP was found to reduce the production of NO in LPS-treated RAW264.7 cells, without causing cytotoxicity. Moreover, this compound suppressed the mRNA levels of inflammatory genes, such as inducible NO synthase (iNOS) and tumor necrosis factor (TNF)-${\alpha}$. Using luciferase reporter gene assays performed in HEK293 cells and immunoblotting analysis with nuclear protein fractions, we determined that MPP reduced the transcriptional activation of nuclear factor (NF)-${\kappa}B$. Furthermore, the activation of a series of upstream signals for NF-${\kappa}B$ activation, composed of Src, Syk, Akt, and $I{\kappa}B{\alpha}$, were also blocked by this compound. It was confirmed that MPP was able to suppress autophosphorylation of overexpressed Src and Syk in HEK293 cells. Therefore, these results suggest that MPP can function as an anti-inflammatory drug with NF-${\kappa}B$ inhibitory properties via the suppression of Src and Syk.

Multiple Effects of a Novel Epothilone Analog on Cellular Processes and Signaling Pathways Regulated by Rac1 GTPase in the Human Breast Cancer Cells

  • Zhang, Hong;An, Fan;Tang, Li;Qiu, Rongguo
    • The Korean Journal of Physiology and Pharmacology
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    • v.18 no.2
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    • pp.109-120
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    • 2014
  • The epothilones are a class of microtubule inhibitors that exhibit a strong antitumor activity. UTD2 is a novel epothilone analog generated by genetic manipulation of the polyketide biosynthetic gene cluster. This study investigated the effects of UTD2 on the actin cytoskeleton and its critical regulators, and the signaling pathways which are essential for cell motility, growth and survival in MCF-7 breast cancer cells. Results showed that UTD2 inhibited the cellular functions of actin cytoskeleton, such as wound-closure, migration and invasion, as well as adhesion. Our study further demonstrated that UTD2 suppressed Rac1 GTPase activation and reduced the activity of PAK1, which is a downstream effector of Rac1, while the activity of Cdc42 was not affected. Additionally, the phosphorylation of p38 and ERK were significantly inhibited, but the phosphorylation of JNK remained the same after UTD2 treatment. Moreover, UTD2 inhibited the activity and mRNA expression of MMP-2, which plays a key role in cell motility. UTD2 also reduced the phosphorylation of Akt, which is an important signaling kinase regulating the cell survival through Rac1. Furthermore, UTD2 interrupted the synergy between Rac1 and Raf in focus formation assays. Taken together, these results indicated that UTD2 exerted multiple effects on the actin cytoskeleton and signaling pathways associated with Rac1. This study provided novel insights into the molecular mechanism of the antineoplastic and antimetastatic activities of epothilones. Our findings also suggest that the signaling pathways regulated by Rac1 may be evaluated as biomarkers for the response to therapy in clinical trials of epothilones.

Effects of Triclosan on Neural Stem Cell Viability and Survival

  • Park, Bo Kyung;Gonzales, Edson Luck T.;Yang, Sung Min;Bang, Minji;Choi, Chang Soon;Shin, Chan Young
    • Biomolecules & Therapeutics
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    • v.24 no.1
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    • pp.99-107
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    • 2016
  • Triclosan is an antimicrobial or sanitizing agent used in personal care and household products such as toothpaste, soaps, mouthwashes and kitchen utensils. There are increasing evidence of the potentially harmful effects of triclosan in many systemic and cellular processes of the body. In this study, we investigated the effects of triclosan in the survivability of cultured rat neural stem cells (NSCs). Cortical cells from embryonic day 14 rat embryos were isolated and cultured in vitro. After stabilizing the culture, triclosan was introduced to the cells with concentrations ranging from $1{\mu}M$ to $50{\mu}M$ and in varied time periods. Thereafter, cell viability parameters were measured using MTT assay and PI staining. TCS decreased the cell viability of treated NSC in a concentration-dependent manner along with increased expressions of apoptotic markers, cleaved caspase-3 and Bax, while reduced expression of Bcl2. To explore the mechanisms underlying the effects of TCS in NSC, we measured the activation of MAPKs and intracellular ROS. TCS at $50{\mu}M$ induced the activations of both p38 and JNK, which may adversely affect cell survival. In contrast, the activities of ERK, Akt and PI3K, which are positively correlated with cell survival, were inhibited. Moreover, TCS at this concentration augmented the ROS generation in treated NSC and depleted the glutathione activity. Taken together, these results suggest that TCS can induce neurodegenerative effects in developing rat brains through mechanisms involving ROS activation and apoptosis initiation.

Microarray Analysis of Alteration in Gene Expression by Acori graminei rhizoma (AGR) Water-Extract in a Hypoxic Model of Cultured Rat Cortical Cells (흰쥐 대뇌세포의 저산소증 모델에서 석창포(石菖浦 Acori graminei rhizoma. AGR)에 의한 유전자 표현 변화의 microarray 분석)

  • Park, Dong-Jun;Jung, Seung-Hyun;Moon, Il-Soo;Lee, Won-Chol;Shin, Gil-Jo
    • Journal of Life Science
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    • v.17 no.1 s.81
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    • pp.150-161
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    • 2007
  • Acori graminei Rhizomn (AGR) is a perennial herb which has been used clinically as a traditional oriental medicine against stroke, Alzheimer's disease, and vascular dementia. We investigated the effect of AGR on the modulation of gene expression profile in a hypoxic model of cultured rat cortical cells. Rat cerebrocortical cells were grown in Neurobasal medium. On DIV12, cells were treated with AGR $(10ug/m\ell)$, given a hypoxic shock (2% $O_2$, 3 hr) on DIV14, and total RNAs were prepared one day after shock. Microarray analyses indicated that the expression levels of most genes were altered within the global M values +0.5 and -0.5, i.e., 40% increase or decrease. There were 750 genes which were upregulated by < global M +0,2, while 700 genes were downregulated by > global M -0.2. The overall profile of gene expression suggests that AGR suppresses apoptosis (upregulation of anti-apopotic genes such as TEGT, TIEG, Dad, p53, and downregulation of pro-apopotic genes such as DAPK, caspase 2, pdcd8), ROS (upregulation of RARa, AhR), and that AGR has neurotrophic effects (upregulation of Aktl, Akt2). These results provide a platform for investigation of the molecular mechanism of the effect of AGR in neuroprotection.