• Interdisciplinary Bio Central
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• v.5 no.4
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• pp.9.1-9.7
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• 2013

Introduction: Tumor necrosis factor receptor-associated protein 1 (TRAP1) is a mitochondrial heat shock protein (HSP), which belongs to HSP90 family. It plays important roles in regulating mitochondrial integrity, protecting against oxidative stress, and inhibiting cell death. Recent studies suggest that TRAP1 is linked to mitochondria and its metabolism. In this study, we established TRAP1 transgenic mice and performed partial hepatectomy (PH) on wild-type (WT) and TRAP1 transgenic mice to investigate the function of TRAP1 during liver regeneration. Results and Discussion: We found that TRAP1 was highly expressed in liver as well as kidney. In addition, liver regeneration slightly decreased together with increased fatty liver and inflammation at 72 hr after PH in TRAP1 transgenic mice compared with WT control group mice. Concomitantly, we observed decreased levels of p38 protein in TRAP1 transgenic mice compared with WT control group mice. These results suggest that TRAP1 plays a critical role in liver energy balance by regulating lipid accumulation during liver regeneration. Conclusions and Prospects: To our knowledge, we reported, for the first time, that liver regeneration slightly reduced together with increased fat accumulations after PH in TRAP1 transgenic mice compared with WT control group mice. Concomitantly, we observed decreased levels of p38 protein in TRAP1 transgenic mice compared with WT control group mice. Overexpression of TRAP1 might affect liver regeneration via disturbing mitochondrial function leading to fatty liver in vivo.

• Journal of Chest Surgery
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• v.50 no.3
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• pp.153-162
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• 2017

Background: The mesenchymal-epithelial transition factor (MET) receptor can be overexpressed in solid tumors, including small cell lung cancer (SCLC). However, the molecular mechanism regulating MET stability and turnover in SCLC remains undefined. One potential mechanism of MET regulation involves the C-terminus of Hsp70-interacting protein (CHIP), which targets heat shock protein 90-interacting proteins for ubiquitination and proteasomal degradation. In the present study, we investigated the functional effects of CHIP expression on MET regulation and the control of SCLC cell apoptosis and invasion. Methods: To evaluate the expression of CHIP and c-Met, which is a protein that in humans is encoded by the MET gene (the MET proto-oncogene), we examined the expression pattern of c-Met and CHIP in SCLC cell lines by western blotting. To investigate whether CHIP overexpression reduced cell proliferation and invasive activity in SCLC cell lines, we transfected cells with CHIP and performed a cell viability assay and cellular apoptosis assays. Results: We found an inverse relationship between the expression of CHIP and MET in SCLC cell lines (n=5). CHIP destabilized the endogenous MET receptor in SCLC cell lines, indicating an essential role for CHIP in the regulation of MET degradation. In addition, CHIP inhibited MET-dependent pathways, and invasion, cell growth, and apoptosis were reduced by CHIP overexpression in SCLC cell lines. Conclusion: C HIP is capable of regulating SCLC cell apoptosis and invasion by inhibiting MET-mediated cytoskeletal and cell survival pathways in NCI-H69 cells. CHIP suppresses MET-dependent signaling, and regulates MET-mediated SCLC motility.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.6
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• pp.315-322
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• 2005

In this study, the authors investigated whether death of vascular smooth muscle cell (VSMC) had a pathological pertinence. Conditioned media obtained from rat aorta smooth muscle cell (SMC) that were induced death by expressing FADD in the absence of tetracycline (FADD-SMC) triggered death of normal SMC. DNA fragmentation and caspase-3 activation were observed in dying SMC by conditioned media. FADD-SMC showed transcriptional activation of tumor necrosis factor $(TNF)-{\alpha}$. Conditioned medium contained $TNF-{\alpha}$, indicating secretion of the cytokine from dying FADD-SMC. It was investigated if secreted $TNF-{\alpha}$ was functional. Conditioned medium activated ERK and p38 MAPK pathways and induced MMP-9 expression, whereas depletion of the cytokine with its soluble receptor (sTNFR) remarkably inhibited induction of MMP-9 by conditioned medium. These findings suggest that $TNF-{\alpha}$ in conditioned medium seems to be active. Then, contribution of $TNF-{\alpha}$ on death-inducing activity of conditioned medium was examined. Depletion of $TNF-{\alpha}$ with soluble $TNF-{\alpha}$ receptor decreased the death activity of conditioned medium by 35%, suggesting that $TNF-{\alpha}$ play a partial role in the death activity. Boiling of medium almost completely abolished the death-inducing activity, suggesting that other heat labile death inducing proteins existed in conditioned medium. Taken together, these results indicate that SMC undergoing death could contribute to inflammation by expressing inflammatory cytokines and pathological complications by inducing death of neighboring cells.

• Journal of Periodontal and Implant Science
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• v.39 no.sup2
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• pp.231-237
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• 2009

Purpose: Cytolethal distending toxin (CDT) is a family of heat-labile cytotoxins produced by several gram-negative mucosa-associated pathogens, including Aggregatibacter actinomycetemcomitans. CDT is well known to be capable of inducing growth arrest, morphological alterations, and eventually death in various cells. CDT belongs to a tripartite $AB_2$ toxin (CdtB: the enzymatic A subunit; CdtA and CdtC: the heterodimeric B subunit). Previous studies proposed that CdtA and CdtC together bind to a cell surface receptor and glycolipids act as a receptor for A. actinomycetemcomitans CDT (AaCDT). In this study, recombinant CdtA and CdtC proteins of AaCDT were co-expressed in a bacterial expression system and tested for their affinity for $GM_1$ ganglioside. Methods: The genes for CdtA and CdtC from A. actinomycetemcomitans Y4 were utilized to construct the expression vectors, pRSET-cdtA and pET28a-cdtC. Both CdtA and CdtC proteins were expressed in Escherichia coli BL21(DE3) and then purified using hexahistidine (His6) tag. The identity of purified protein was confirmed by anti-His6 antibody and monoclonal anti-CdtA antibody. Furthermore, the affinity of recombinant protein to $GM_1$ ganglioside was checked through ELISA. Results: Recombinant CdtA and CdtC proteins were expressed as soluble proteins and reacted to anti-His6 and monoclonal anti-CdtA antibodies. ELISA revealed that purified soluble CdtA-CdtC protein bound to $GM_1$ ganglioside, while CdtA alone did not. Conclusions: Co-expression of CdtA and CdtC proteins enhanced the solubility of the proteins in E. coli, leading to convenient preparation of active CdtA-CdtC, a critical material for the study of AaCDT pathogenesis.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3471-3476
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• 2012

Background and Objective: Histone deacetylase (HDAC) inhibitors represent a promising class of potential anticancer agents for treatment of human malignancies. In this study, we investigated the effect of trichostatin A (TSA), one such HDAC inhibitor, in combination with docetaxel (TXT), a cytotoxic chemotherapy agent or erlotinib, a novel molecular target therapy drug, on lung cancer A549 cells. Methods: A549 cells were treated with TXT, erlotinib alone or in combination with TSA, respectively. Cell viability, apoptosis, and cell cycle distribution were evaluated using MTT (3- (4, 5-dimethylthiazol-2-yl) -2, 5-diphenyltetrazolium bromide) assay, Hochst33258 staining and flow cytometry. Moreover, immunofluorescent staining and Western blot analysis were employed to examine alterations of ${\alpha}$-tubulin, heat shock protein 90 (hsp90), epidermal growth factor receptor (EGFR), and caspase-3 in response to the different exogenous stimuli. Results: Compared with single-agent treatment, co-treatment of A549 cells with TSA/TXT or TSA/erlotinib synergistically inhibited cell proliferation, induced apoptosis, and caused cell cycle delay at the $G_2/M$ transition. Treatment with TSA/TXT or TSA/erlotinib led to a significant increase of cleaved caspase-3 expression, also resulting in elevated acetylation of ${\alpha}$-tubulin or hsp90 and decreased expression of EGFR, which was negatively associated with the level of acetylated hsp90. Conclusions: Synergistic anti-tumor effects are observed between TXT or erlotinib and TSA on lung cancer cells. Such combinations may provide a more effective strategy for treating human lung cancer.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.1
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• pp.134-141
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• 2016

To investigate the role of polysaccharide from Acanthopanax senticosus (ASPS) in preventing lipopolysaccharide (LPS)-induced intestinal injury, 18 mice (at 5 wk of age) were assigned to three groups with 6 replicates of one mouse each. Mice were administrated by oral gavage with or without ASPS (300 mg/kg body weight) for 14 days and were injected with saline or LPS at 15 days. Intestinal samples were collected at 4 h post-challenge. The results showed that ASPS ameliorated LPS-induced deterioration of digestive ability of LPS-challenged mice, indicated by an increase in intestinal lactase activity (45%, p<0.05), and the intestinal morphology, as proved by improved villus height (20.84%, p<0.05) and villus height:crypt depth ratio (42%, p<0.05), and lower crypt depth in jejunum (15.55%, p<0.05), as well as enhanced intestinal tight junction proteins expression involving occludin-1 (71.43%, p<0.05). ASPS also prevented intestinal inflammation response, supported by decrease in intestinal inflammatory mediators including tumor necrosis factor ${\alpha}$ (22.28%, p<0.05) and heat shock protein (HSP70) (77.42%, p<0.05). In addition, intestinal mucus layers were also improved by ASPS, as indicated by the increase in number of goblet cells (24.89%, p<0.05) and intestinal trefoil peptide (17.75%, p<0.05). Finally, ASPS facilitated mRNA expression of epidermal growth factor (100%, p<0.05) and its receptor (200%, p<0.05) gene. These results indicate that ASPS can prevent intestinal mucosal barrier injury under inflammatory conditions, which may be associated with up-regulating gene mRNA expression of epidermal growth factor and its receptor.

• The Journal of the Korean Society for Microbiology
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• v.35 no.2
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• pp.149-157
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• 2000

Mycobacterium tuberculosis is capable of growing and survival within macrophage. The purpose of this study was to identify the genes regulated by infection of mycobacteria in human monocytic THP-1 cells. We used the differential display reverse transcriptase polymerase chain reaction (DD RT-PCR) and nothern blot analysis to confirm the differentially expressed genes from THP-1 cells infected with live Mycobacterium tuberculosis H37Rv, heat-killed Mycobacterium tuberculosis H37Rv and live Mycobacterium bovis BCG. Among many up or down-regulated clones, 27 clones were sequenced and compared with known genes on GenBank. Thirteen of over-expressed clones from THP-1 cells infected with live Mycobacterium tuberculosis H37Rv were identical to human prothymosin alpha, eight were novel clones and six clones showed homology with Human ferritin H chain, Esherichia coli bgl, Mouse RNA-dependent EIF-2 alpha kinase, E. coli htrL, Hyaluronan receptor and T cell receptor. Our result suggests that Mycobacterium tuberculosis might regulate prothymosin alpha gene transcription in monocytic THP-1 cell.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.1
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• pp.21-25
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• 2004

People in tropics have the ability to tolerate heat by residential permanence in the tropics. Previously, we have shown that African and Thai subjects who lived for whole their lives in only their respective countries sweat less under hot conditions than South Koreans who also lived whole their lives in Korea. The difference in sweating responses was attributed to the dissimilar central and peripheral sweating mechanisms operating in people from both groups. In the present study, acetylcholine (ACh), the primary transmitter for the sudomotor functions, was iontophoretically administered to South Koreans and Africans to determine the characteristic sudorific responses of their acclimatized biologic make-up to their respective environments. Using quantitative sudomotor axon reflex test (QSART), direct (DIR) and axon reflex (AXR) responses were evaluated. The findings revealed that the sweat onset-time among South Koreans was 0.91 min earlier than among Africans (P<0.01). The axon reflex sweat volume of nicotine receptor activity AXR(1) and sweat volume of muscarinic receptor activity DIR(2) among South Koreans were 79% and 53% greater (P<0.01), respectively. These results indicate that the reduced thermal sweating among Africans is at least in part attributed to the diminished sensitivity of sweat glands to ACh.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.6
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• pp.387-392
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• 2012

In this study, we examined the antinociceptive effect of Cyperi rhizoma (CR) and Corydalis tuber (CT) extracts using a chronic constriction injury-induced neuropathic pain rat model. After the ligation of sciatic nerve, neuropathic pain behavior such as mechanical allodynia and thermal hyperalgesia were rapidly induced and maintained for 1 month. Repeated treatment of CR or CT (per oral, 10 or 30 mg/kg, twice a day) was performed either in induction (day 0~5) or maintenance (day 14~19) period of neuropathic pain state. Treatment of CR or CT at doses of 30 mg/kg in the induction and maintenance periods significantly decreased the nerve injury-induced mechanical allodynia. In addition, CR and CT at doses of 10 or 30 mg/kg alleviated thermal heat hyperalgesia when they were treated in the maintenance period. Finally, CR or CT (30 mg/kg) treated during the induction period remarkably reduced the nerve injury-induced phosphorylation of NMDA receptor NR1 subunit (pNR1) in the spinal dorsal horn. Results of this study suggest that extracts from CR and CT may be useful to alleviate neuropathic pain.

• The Korean Journal of Pain
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• v.35 no.4
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• pp.391-402
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• 2022

Background: The mechanism of peripheral axon transport in neuropathic pain is still unclear. Chemokine ligand 13 (CXCL13) and its receptor (C-X-C chemokine receptor type 5, CXCR5) as well as GABA transporter 1 (GAT-1) play an important role in the development of pain. The aim of this study was to explore the axonal transport of CXCL13/CXCR5 and GAT-1 with the aid of the analgesic effect of botulinum toxin type A (BTX-A) in rats. Methods: Chronic constriction injury (CCI) rat models were established. BTX-A was administered to rats through subcutaneous injection in the hind paw. The pain behaviors in CCI rats were measured by paw withdrawal threshold and paw withdrawal latencies. The levels of CXCL13/CXCR5 and GAT-1 were measured by western blots. Results: The subcutaneous injection of BTX-A relieved the mechanical allodynia and heat hyperalgesia induced by CCI surgery and reversed the overexpression of CXCL13/CXCR5 and GAT-1 in the spinal cord, dorsal root ganglia (DRG), sciatic nerve, and plantar skin in CCI rats. After 10 mmol/L colchicine blocked the axon transport of sciatic nerve, the inhibitory effect of BTX-A disappeared, and the levels of CXCL13/CXCR5 and GAT-1 in the spinal cord and DRG were reduced in CCI rats. Conclusions: BTX-A regulated the levels of CXCL13/CXCR5 and GAT-1 in the spine and DRG through axonal transport. Chemokines (such as CXCL13) may be transported from the injury site to the spine or DRG through axonal transport. Axon molecular transport may be a target to enhance pain management in neuropathic pain.