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Zhang Y, Dong R, Yang Q, Zhang L, Li J, Zhao H. [Resveratrol upregulates the gene and protein expressions of N-methyl-D-aspartate receptor 1 and protein kinase C in the hippocampus in Alzheimer's disease rats]. Wei Sheng Yan Jiu 2019; 48:269-278. [PMID: 31133106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
OBJECTIVE To investigate the effects of resveratrol(Res) on N-methyl-D-aspartate receptor(NMDAR1)and protein kinase C(PKC)expressions in the hippocampus in Alzheimer's disease(AD) rats. METHODS The model of AD was induced by ovariectomy combined intraperitoneal injection of D-galactose(100 mg/kg). Thirty-Six female Wistar rats were randomly divided into 6 groups inculding Sham control group, AD model group, Res low dose group(20 mg/kg), Res middle dose group(40 mg/kg), Res high dose group(80 mg/kg group)and estrogen replacement therapy(ERT) group. The genes of NMDAR1 and PKC were detected by real-time PCR. NMDAR1 total protein, p-NMDAR1 protein and PKC protein were checked by Western blot. RESULTS Compared with the Sham control group, the gene expressions and the protein expressions of NMDAR1 and PKC in the model group were decreased(P<0. 05). Moreover, compared with the model group, genes of NMDAR1 and PKC in the 3 Res dose groups were significantly increased(P<0. 05 or P<0. 01). The elavated levels of genes of NMDAR1 and PKC in ERT group were similar to the Res 80 mg/kg group(P<0. 01). p-NMDAR1/NMDAR1 and the protein expressions of PKC were also significantly increased in Res 40 mg/kg group and Res 80 mg/kg group as well as in ERT group(P<0. 05 or P<0. 01). CONCLUSION Up-regulating the gene and protein expressions of p-NMDAR1/NMDAR1 and PKC may be one of the mechanisms of improvement of Res on the memory in AD rats.
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Affiliation(s)
- Yusen Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Shanxi Medical University, Taiyuan 030001, China
| | - Ruirui Dong
- Department of Nutrition and Food Hygiene, School of Public Health, Shanxi Medical University, Taiyuan 030001, China
| | - Qian Yang
- Department of Nutrition and Food Hygiene, School of Public Health, Shanxi Medical University, Taiyuan 030001, China
| | - Luping Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Shanxi Medical University, Taiyuan 030001, China
| | - Jing Li
- Department of Nutrition and Food Hygiene, School of Public Health, Shanxi Medical University, Taiyuan 030001, China
| | - Haifeng Zhao
- Department of Nutrition and Food Hygiene, School of Public Health, Shanxi Medical University, Taiyuan 030001, China
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Yang CY, Liu SY, Wang HY, Li YL, Guo D, Wang XY, Hua W, Wang GL. Neuroprotection by Propofol Post-Conditioning: Focus on PKMζ/KCC2 Pathway Activity. Cell Mol Neurobiol 2018; 38:691-701. [PMID: 28779332 DOI: 10.1007/s10571-017-0530-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 07/31/2017] [Indexed: 12/11/2022]
Abstract
Critical and major operations are often accompanied by brain ischemic complications. Previous studies found that propofol post-conditioning provided neuroprotective functions through upregulating the expression of potassium chloride cotransporter 2 (KCC2) in gamma-aminobutyric acid (GABA) interneurons. Membrane expression and phosphorylation represents KCC2 activity, which were modulated by a protein kinase C (PKC)-dependent mechanism. However, the role of propofol in increasing KCC2 phosphorylation and the involvement of protein kinase Mζ (PKMζ), a major subtype of PKC, in the KCC2 pathway remained unclear. In this study, we established middle cerebral artery occlusion model in rats to evaluate the long-term recovery of brain functions using behavioral experiments. KCC2 and PKMζ were assessed via western blot. We used the selective inhibitor, zeta inhibitory peptide (ZIP), to investigate the relationship between KCC2 and PKMζ. Intracellular chloride concentration in the hippocampal CA1 area was measured to determine KCC2 activity. We found that propofol, infused at a speed of 20 mg kg-1 h-1 for 2 h at the onset of reperfusion, improved neurological deficits and cognitive dysfunction following ischemia/reperfusion injury. PKMζ expression was significantly upregulated, which improved KCC2 membrane expression and phosphorylation in the ischemic hippocampal CA1 area, and these effects could last up to 28 days. But ZIP inhibited this process. Ultimately, we showed that propofol increased KCC2 phosphorylation and PKMζ was the upstream of KCC2. Propofol led to long-term recovery of brain functions by upregulating the activity of the PKMζ/KCC2 pathway.
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Affiliation(s)
- Chen-Yi Yang
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Shu-Ying Liu
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Hai-Yun Wang
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China.
- Tianjin Research Institute of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China.
| | - Yan-Li Li
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Di Guo
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Xin-Yue Wang
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Wei Hua
- Department of Anesthesiology, Tianjin Third Central Hospital, Third Central Clinical College of Tianjin Medical University, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Research Centre of the Ministry of Health, Tianjin, 300170, China
| | - Guo-Lin Wang
- Tianjin Research Institute of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
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Abstract
Aging is associated with increase in oxidative stress. Earlier, we have shown that higher basal protein kinase C (PKC) activity in the proximal tubules (PTs) of old rats contributes to the hyperphosphorylation of Na,K-ATPase and subsequent decrease in basal Na,K-ATPase activity, resulting in diminished natriuretic response to dopamine in these animals. We hypothesized that the increase in PKC activity in PTs of old rats is caused by increased oxidative stress and that antioxidants administration should reduce/normalize the elevated PKC activity in the renal PTs of old rats. We studied the effect of two antioxidants, namely, α-lipoic acid (LA) and tempol, on oxidants level and PKC activity in the PTs of adult (6-month) and old (24-month) Fischer 344 rats. We found that the accumulation of fluorescent dichlorofluorescein (DCF), an indicator of oxidant production, was higher in the PTs of old compared to adult rats. Dietary supplementation with LA for 2 weeks normalized the increased DCF level in old rats. Carboxymethylysine and malondialdehyde, markers of oxidative damage, were elevated in the PTs of old rats, which were normalized to the level of adult rats when tempol was provided in drinking water for 3 weeks. Both LA and tempol treatment also normalized the higher basal PKC activity in the PTs of old rats to the level seen in adult rats. These results suggest that increase in oxidative stress causes an increase in PKC activity, and that antioxidants, while reducing oxidative stress, also normalize PKC activity in the PTs of old rats.
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Affiliation(s)
- Mohammad Asghar
- Heart and Kidney Institute, College of Pharmacy, University of Houston, Houston, Texas 77204, USA
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Tsai JY, Rédei D, Forgo P, Li Y, Vasas A, Hohmann J, Wu CC. Isolation of Phorbol Esters from Euphorbia grandicornis and Evaluation of Protein Kinase C- and Human Platelet-Activating Effects of Euphorbiaceae Diterpenes. J Nat Prod 2016; 79:2658-2666. [PMID: 27731641 DOI: 10.1021/acs.jnatprod.6b00603] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Human platelets contain conventional (α and β) and novel isoforms of PKC (δ and θ), and PKC activation can result in platelet aggregation and secretion reaction that are important for thrombus formation. Several tumor-promoting Euphorbiaceae diterpenes are known to act as direct activators of PKC, but many types of such diterpenes have not been studied as platelet stimulators. In the present study, two new and five known phorbol esters were isolated from Euphorbia grandicornis. Two of the isolated phorbol esters together with compounds representing ingenane, jatrophane, and myrsinane structural types were studied on PKC activation and platelet stimulation. The investigated phorbol esters and ingenane esters induced blood platelet aggregation and ATP secretion. PKC activation was demonstrated by inducing membrane translocation of PKCs, phosphorylation of PKC substrates, and activation of PKC signaling pathways. The PKC-activating effect of the compounds correlated well with their efficacy to cause platelet stimulation. Moreover, by using an isoform-specific PKC inhibitor, it was found that besides conventional PKCs novel PKCs also play a positive role in platelet activation caused by phorbol/ingenane esters, especially in regulating platelet aggregation. The present results suggest that platelets afford a useful model for studying PKC activators of natural origin or their chemical derivatives.
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Affiliation(s)
- Ju-Ying Tsai
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Dóra Rédei
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Peter Forgo
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Yu Li
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Andrea Vasas
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Judit Hohmann
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
| | - Chin-Chung Wu
- Graduate Institute of Natural Products and ‡Research Center for Natural Products and Drug Development, Kaohsiung Medical University , Kaohsiung 807, Taiwan
- Department of Pharmacognosy and ⊥Interdisciplinary Centre for Natural Products, University of Szeged , Eötvös u. 6, H-6720 Szeged, Hungary
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Staveness D, Abdelnabi R, Near KE, Nakagawa Y, Neyts J, Delang L, Leyssen P, Wender PA. Inhibition of Chikungunya Virus-Induced Cell Death by Salicylate-Derived Bryostatin Analogues Provides Additional Evidence for a PKC-Independent Pathway. J Nat Prod 2016; 79:680-4. [PMID: 26900711 PMCID: PMC4942189 DOI: 10.1021/acs.jnatprod.5b01017] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Chikungunya virus (CHIKV) has been spreading rapidly, with over one million confirmed or suspected cases in the Americas since late 2013. Infection with CHIKV causes devastating arthritic and arthralgic symptoms. Currently, there is no therapy to treat this disease, and the only medications focus on relief of symptoms. Recently, protein kinase C (PKC) modulators have been reported to inhibit CHIKV-induced cell death in cell assays. The salicylate-derived bryostatin analogues described here are structurally simplified PKC modulators that are more synthetically accessible than the natural product bryostatin 1, a PKC modulator and clinical lead for the treatment of cancer, Alzheimer's disease, and HIV eradication. Evaluation of the anti-CHIKV activity of these salicylate-derived bryostatin analogues in cell culture indicates that they are among the most potent cell-protective agents reported to date. Given that they are more accessible and significantly more active than the parent natural product, they represent new therapeutic leads for controlling CHIKV infection. Significantly, these analogues also provide evidence for the involvement of a PKC-independent pathway. This adds a fundamentally distinct aspect to the importance or involvement of PKC modulation in inhibition of chikungunya virus replication, a topic of recent and growing interest.
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Affiliation(s)
- Daryl Staveness
- Departments of Chemistry and Chemical and Systems Biology, Stanford University, Stanford, California 94305, United States
| | - Rana Abdelnabi
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven–University of Leuven, B-3000 Leuven, Belgium
| | - Katherine E. Near
- Departments of Chemistry and Chemical and Systems Biology, Stanford University, Stanford, California 94305, United States
| | - Yu Nakagawa
- Departments of Chemistry and Chemical and Systems Biology, Stanford University, Stanford, California 94305, United States
| | - Johan Neyts
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven–University of Leuven, B-3000 Leuven, Belgium
| | - Leen Delang
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven–University of Leuven, B-3000 Leuven, Belgium
| | - Pieter Leyssen
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven–University of Leuven, B-3000 Leuven, Belgium
| | - Paul A. Wender
- Departments of Chemistry and Chemical and Systems Biology, Stanford University, Stanford, California 94305, United States
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Velloso EP, Pimentel RL, Braga JF, Cabral ACV, Reis ZSN, Bader M, Santos RAS, Wallukat G. Identification of a Novel Agonist-Like Autoantibody in Preeclamptic Patients. Am J Hypertens 2016; 29:405-12. [PMID: 26158852 DOI: 10.1093/ajh/hpv099] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 06/08/2015] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Recent studies have shown that preeclampsia (PE) is associated with the presence of autoantibodies (AABs) that activate the angiotensin II AT1 receptor, which could contribute to many of the symptoms of PE. METHODS To investigate the frequency and the targets of AABs in preeclamptic women (31 cases) and healthy pregnant normotensive women (29 cases) in Brazil, antibodies from serum samples were detected by a bioassay using spontaneously beating neonatal rat cardiomyocytes in culture. In the cardiomyocytes, the agonistic AABs induce a positive or negative chronotropic response, mimicking the corresponding receptor agonists. The specificity of the AAB response was identified by specific receptor antagonists. RESULTS Thirty preeclamptic patients (97%) presented AABs against the angiotensin II AT1 receptor. The agonistic effect of the AAB was blocked by irbesartan and neutralized by a peptide corresponding to the second extracellular loop of this receptor. Strikingly, we discovered that all sera from the severe preeclamptic patients (16 cases) contained a novel agonist-like AAB directed against the endothelin-1 ETA receptor in addition to the AABs against the angiotensin II AT1 receptor. This AAB was selectively blocked by the antagonist BQ-123, antagonized by the protein kinase C (PKC) inhibitor Calphostin C and neutralized by peptides corresponding to the second extracellular loop of the endothelin-1 ETA receptor subtype. CONCLUSIONS We described, for the first time, the presence of endothelin-1 ETA receptor AABs in PE. Our results suggest that the presence of both agonistic AABs may be involved in the pathogenesis of severe PE.
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MESH Headings
- Adult
- Angiotensin II Type 1 Receptor Blockers/pharmacology
- Animals
- Autoantibodies/immunology
- Autoantibodies/pharmacology
- Biphenyl Compounds/pharmacology
- Case-Control Studies
- Endothelin Receptor Antagonists/pharmacology
- Enzyme Inhibitors/pharmacology
- Female
- Gestational Age
- Heart Rate/drug effects
- Humans
- Irbesartan
- Myocytes, Cardiac/drug effects
- Naphthalenes/pharmacology
- Peptides, Cyclic/pharmacology
- Pre-Eclampsia/immunology
- Pregnancy
- Pregnancy Trimester, Third
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C/drug effects
- Protein Kinase C/immunology
- Rats
- Rats, Wistar
- Receptor, Angiotensin, Type 1/drug effects
- Receptor, Angiotensin, Type 1/immunology
- Receptor, Endothelin A/drug effects
- Receptor, Endothelin A/immunology
- Severity of Illness Index
- Tetrazoles/pharmacology
- Young Adult
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Affiliation(s)
- Elizabeth Portugal Velloso
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Renata Lúcia Pimentel
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Janaína F Braga
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Antônio Carlos Vieira Cabral
- Department of Gynecology and Obstetrics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Zilma Silveira N Reis
- Department of Gynecology and Obstetrics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Michael Bader
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin-Buch, Germany
| | - Robson Augusto S Santos
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil;
| | - Gerd Wallukat
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin-Buch, Germany
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Chow LH, Tao PL, Chen YH, Lin YH, Huang EYK. Angiotensin IV possibly acts through PKMzeta in the hippocampus to regulate cognitive memory in rats. Neuropeptides 2015; 53:1-10. [PMID: 26412453 DOI: 10.1016/j.npep.2015.09.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 08/10/2015] [Accepted: 09/10/2015] [Indexed: 10/23/2022]
Abstract
Ang IV is an endogenous peptide generated from the degradation of angiotensin II. Ang IV was found to enhance learning and memory in CNS. PKMzeta was identified to be a fragment of PKCzeta (protein kinase Czeta). Its continuous activation was demonstrated to be correlated with the formation of memory in the hippocampus. Therefore, we investigated whether PKMzeta participates in the effects of Ang IV on memory. We first examined the effect of Ang IV on non-spatial memory/cognition in modified object recognition test in rats. Our data showed that Ang IV could increase the exploration time on novel object. The co-administration of ZIP (PKMzeta inhibitor) with Ang IV significantly blocked the effect by Ang IV. The effects of Ang IV on hippocampal LTP at the CA1 region were also evaluated. Ang IV significantly increased the amplitude and slope of the EPSPs, which was consistent with other reports. Surprisingly, instead of potentiating LTP, Ang IV caused a failed maintenance of LTP. Moreover, there was no quantitative change in PKMzeta induced by Ang IV and/or ZIP after behavioral experiments. Taken together, our data re-confirmed the finding of the positive effect of Ang IV to enhance memory/cognition. The increased strength of EPSPs with Ang IV could also have certain functional relevance. Since the behavioral results suggested the involvement of PKMzeta, we hypothesized that the enhancement of memory/cognition by Ang IV may rely on an increase in PKMzeta activity. Overall, the present study provided important advances in our understanding of the action of Ang IV in the hippocampus.
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Affiliation(s)
- Lok-Hi Chow
- Department of Pharmacology, National Defense Medical Center, Nei-Hu, 114 Taipei, Taiwan, ROC; Department of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Anesthesiology, School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Pao-Luh Tao
- Center for Neuropsychiatric Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Yuan-Hao Chen
- Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Nei-Hu, 114 Taipei, Taiwan, ROC
| | - Yu-Hui Lin
- Department of Pharmacology, National Defense Medical Center, Nei-Hu, 114 Taipei, Taiwan, ROC
| | - Eagle Yi-Kung Huang
- Department of Pharmacology, National Defense Medical Center, Nei-Hu, 114 Taipei, Taiwan, ROC.
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Son ES, Kyung SY, Lee SP, Jeong SH, Shin JY, Ohba M, Yeo EJ, Park JW. Role of protein kinase C-η in cigarette smoke extract-induced apoptosis in MRC-5-cells. Hum Exp Toxicol 2015; 34:869-77. [PMID: 25504686 DOI: 10.1177/0960327114561343] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Cigarette smoke (CS) is a major risk factor for emphysema, which causes cell death in structural cells of the lung by mechanisms that are still not completely understood. We demonstrated previously that CS extract (CSE) induces caspase activation in MRC-5 human lung fibroblasts, activated protein kinase C-η (PKC-η), and translocated PKC-η from the cytosol to the membrane. The objective of this study was to investigate the involvement of PKC-η activation in a CSE-induced extrinsic apoptotic pathway. We determined that CSE increases expression of caspase 3 and 8 cleavage in MRC-5 cells and overexpression of PKC-η significantly increased expression of caspase 3 and 8 cleavage compared with control LacZ-infected cells. In contrast, dominant negative (dn) PKC-η inhibited apoptosis in MRC-5 cells exposed to CSE and decreased expression of caspase 3 and 8 compared with control cells. Exposure to 10% CSE for >8 h significantly increased lactate dehydrogenase release in PKC-η-infected cells compared with LacZ-infected cells. Additionally, PKC-η-infected cells had an increased number of Hoechst 33342 stained nuclei compared with LacZ-infected cells, while dn PKC-η-infected cells exhibited fewer morphological changes than LacZ-infected cells under phase-contrast microscopy. In conclusion, PKC-η activation plays a pro-apoptotic role in CSE-induced extrinsic apoptotic pathway in MRC-5 cells. These results suggest that modulation of PKC-η may be a useful tool for regulating the extrinsic apoptosis of MRC-5 cells by CSE and may have therapeutic potential in the treatment of CS-induced lung injury.
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Affiliation(s)
- E S Son
- Department of Pulmonary, Allergy and Critical Care Medicine, Gachon University, Gil Medical Center, Namdong-Gu, Incheon, Republic of Korea
| | - S Y Kyung
- Department of Pulmonary, Allergy and Critical Care Medicine, Gachon University, Gil Medical Center, Namdong-Gu, Incheon, Republic of Korea
| | - S P Lee
- Department of Pulmonary, Allergy and Critical Care Medicine, Gachon University, Gil Medical Center, Namdong-Gu, Incheon, Republic of Korea
| | - S H Jeong
- Department of Pulmonary, Allergy and Critical Care Medicine, Gachon University, Gil Medical Center, Namdong-Gu, Incheon, Republic of Korea
| | - J Y Shin
- Department of Pulmonary, Allergy and Critical Care Medicine, Gachon University, Gil Medical Center, Namdong-Gu, Incheon, Republic of Korea
| | - M Ohba
- Institute of Molecular Oncology, Showa University, Hatanodai, Shinagawa-ku, Tokyo, Japan
| | - E J Yeo
- Department of Biochemistry, School of Medicine, Gachon University, Yeonsu-Gu, Incheon, Republic of Korea
| | - J W Park
- Department of Pulmonary, Allergy and Critical Care Medicine, Gachon University, Gil Medical Center, Namdong-Gu, Incheon, Republic of Korea
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9
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Kedei N, Kraft MB, Keck GE, Herald CL, Melody N, Pettit GR, Blumberg PM. Neristatin 1 provides critical insight into bryostatin 1 structure-function relationships. J Nat Prod 2015; 78:896-900. [PMID: 25808573 PMCID: PMC4415049 DOI: 10.1021/acs.jnatprod.5b00094] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Indexed: 06/04/2023]
Abstract
Bryostatin 1, a complex macrocyclic lactone isolated from Bugula neritina, has been the subject of multiple clinical trials for cancer. Although it functions as an activator of protein kinase C (PKC) in vitro, bryostatin 1 paradoxically antagonizes most responses to the prototypical PKC activator, the phorbol esters. The bottom half of the bryostatin 1 structure has been shown to be sufficient to confer binding to PKC. In contrast, we have previously shown that the top half of the bryostatin 1 structure is necessary for its unique biological behavior to antagonize phorbol ester responses. Neristatin 1 comprises a top half similar to that of bryostatin 1 together with a distinct bottom half that confers PKC binding. We report here that neristatin 1 is bryostatin 1-like, not phorbol ester-like, in its biological activity on U937 promyelocytic leukemia cells. We conclude that the top half of the bryostatin 1 structure is largely sufficient for bryostatin 1-like activity, provided the molecule also possesses an appropriate PKC binding domain.
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Affiliation(s)
- Noemi Kedei
- Laboratory
of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892-4255, United States
| | - Matthew B. Kraft
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Gary E. Keck
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Cherry L. Herald
- Department of Chemistry and Biochemistry, Arizona State University, P.O. Box 871604, Tempe, Arizona 85287-1604, United States
| | - Noeleen Melody
- Department of Chemistry and Biochemistry, Arizona State University, P.O. Box 871604, Tempe, Arizona 85287-1604, United States
| | - George R. Pettit
- Department of Chemistry and Biochemistry, Arizona State University, P.O. Box 871604, Tempe, Arizona 85287-1604, United States
| | - Peter M. Blumberg
- Laboratory
of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892-4255, United States
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10
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Laird GM, Bullen CK, Rosenbloom DIS, Martin AR, Hill AL, Durand CM, Siliciano JD, Siliciano RF. Ex vivo analysis identifies effective HIV-1 latency-reversing drug combinations. J Clin Invest 2015; 125:1901-12. [PMID: 25822022 DOI: 10.1172/jci80142] [Citation(s) in RCA: 303] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 02/06/2015] [Indexed: 02/06/2023] Open
Abstract
Reversal of HIV-1 latency by small molecules is a potential cure strategy. This approach will likely require effective drug combinations to achieve high levels of latency reversal. Using resting CD4+ T cells (rCD4s) from infected individuals, we developed an experimental and theoretical framework to identify effective latency-reversing agent (LRA) combinations. Utilizing ex vivo assays for intracellular HIV-1 mRNA and virion production, we compared 2-drug combinations of leading candidate LRAs and identified multiple combinations that effectively reverse latency. We showed that protein kinase C agonists in combination with bromodomain inhibitor JQ1 or histone deacetylase inhibitors robustly induce HIV-1 transcription and virus production when directly compared with maximum reactivation by T cell activation. Using the Bliss independence model to quantitate combined drug effects, we demonstrated that these combinations synergize to induce HIV-1 transcription. This robust latency reversal occurred without release of proinflammatory cytokines by rCD4s. To extend the clinical utility of our findings, we applied a mathematical model that estimates in vivo changes in plasma HIV-1 RNA from ex vivo measurements of virus production. Our study reconciles diverse findings from previous studies, establishes a quantitative experimental approach to evaluate combinatorial LRA efficacy, and presents a model to predict in vivo responses to LRAs.
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Poveda E. Ingenol derivates promising for HIV eradication. AIDS Rev 2014; 16:246. [PMID: 25373349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The eradication of HIV is at this moment one of the greatest challenges in the fight against HIV/AIDS. Despite the prolonged effectiveness of current anti-HIV therapies, capable of keeping patients with undetectable viremia for long periods of time, HIV-infected patients cannot be cured due to the establishment of HIV latent reservoirs. Therefore, several therapeutic strategies are being evaluated to eliminate these viral reservoirs. One of these strategies, termed “shock and kill”, aims to attack the latent reservoir by simultaneous treatment with HIV-activating agents to stimulate viral replication in latently infected cells and antiretroviral therapy to block new infections. A number of compounds have been suggested for the shock and kill strategy including histone deacetylase inhibitors (HDACI), histone methyltransferases (HMT), DNA methyltransferase inhibitors (DNMTI), and protein kinase C (PKC) activators.
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Affiliation(s)
- Eva Poveda
- Division of Clinical Virology, INIBIC-Complejo Hospitalario Universitario de A Coruña, A Coruña, Spain
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Abstract
CONTEXT Bryostatins represent an important group of pharmaceutically promising substances. These compounds are produced by commensal microorganisms naturally occurring in marine invertebrates, mainly in bryozoans. The most frequently investigated substance is bryostatin-1, which is a highly oxygenated macrolide with a polyacetate backbone. OBJECTIVE The aim of this work was to summarize documented preclinical and clinical effects of bryostatin-class compounds. METHODS A literature search was made of Medline and Web of Science databases in 2012. RESULTS AND CONCLUSION Our review showed that bryostatins are potent agonists of protein kinase C. In addition to this, their significant antineoplastic activity against several tumor types has also been established and described. Bryostatin's anticancer activity has been proved against various cancer types. Moreover, significant results have been achieved by using bryostatin-1 in combination with other therapies, including combination with vaccine testing. Concerning other important properties that bryostatins possess, their ability to sensitize some resistant cells to chemotherapy agents, or immunoactivity and further stimulating growth of new neural connections, and enhancing effect on long-term memory are worth mentioning. In particular, some new bryostatin analogs could represent potential therapeutic agent for the treatment of cancer and other diseases in future.
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Affiliation(s)
- Peter Kollár
- Department of Human Pharmacology and Toxicology, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno , Brno , Czech Republic
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Abstract
Currently emerging concepts of maladaptive pain and fear suggest that they share basic neuronal circuits and cellular mechanisms of memory formation. Recent studies have revealed processes of erasing memory traces of pain and fear that may be promising targets for future therapies.
Pain and fear are both aversive experiences that strongly impact on behaviour and well being. They are considered protective when they lead to meaningful, adaptive behaviour such as the avoidance of situations that are potentially dangerous to the integrity of tissue (pain) or the individual (fear). Pain and fear may, however, become maladaptive if expressed under inappropriate conditions or at excessive intensities for extended durations. Currently emerging concepts of maladaptive pain and fear suggest that basic neuronal mechanisms of memory formation are relevant for the development of pathological forms of pain and fear. Thus, the processes of erasing memory traces of pain and fear may constitute promising targets for future therapies.
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MESH Headings
- Analgesics, Opioid/pharmacology
- Analgesics, Opioid/therapeutic use
- Animals
- Anxiety/etiology
- Anxiety/psychology
- Conditioning, Classical/physiology
- Cycloserine/pharmacology
- Cycloserine/therapeutic use
- Extinction, Psychological/physiology
- Fear/drug effects
- Fear/psychology
- Humans
- Hyperalgesia/etiology
- Hyperalgesia/prevention & control
- Hyperalgesia/psychology
- Hyperalgesia/therapy
- Isoenzymes/drug effects
- Isoenzymes/physiology
- Long-Term Potentiation/drug effects
- Long-Term Potentiation/physiology
- Memory, Long-Term/drug effects
- Memory, Long-Term/physiology
- Mental Recall/drug effects
- Mental Recall/physiology
- Models, Neurological
- Models, Psychological
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/physiology
- Neuroglia/physiology
- Nociception/physiology
- Pain/psychology
- Pain Management/methods
- Protein Kinase C/drug effects
- Protein Kinase C/physiology
- Protein Kinase Inhibitors/therapeutic use
- Protein Kinases/physiology
- Rats
- Receptors, Ionotropic Glutamate/drug effects
- Receptors, Ionotropic Glutamate/physiology
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Affiliation(s)
- Jürgen Sandkühler
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria
| | - Jonathan Lee
- University of Birmingham, School of Psychology, Edgbaston, Birmingham B15 2TT, UK
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Wasilewska-Dziubinska E, Gajewska A, Herman A, Wolinska-Witort E, Skrzypska J, Martynska L, Kalisz M, Chmielowska M. The effect of valproate (VPA) treatment on inositol phosphates (IPs) accumulation in non-stimulated and GnRH-treated female rat anterior pituitary cells in vitro. Neuro Endocrinol Lett 2013; 34:302-308. [PMID: 23803874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 05/15/2013] [Indexed: 06/02/2023]
Abstract
OBJECTIVE Mechanism(s) responsible for VPA-induced effects on reproductive axis activity are not fully recognized. Previously we reported that VPA suppressed only GnRH-stimulated but not the basal LH release from rat anterior pituitary (AP) cells in vitro. Since the inhibitory effect of VPA was exerted only in GnRH-activated cells, potential VPA impact on GnRH-R-coupled IP3/PKC signaling could not be excluded. In this study the effect of VPA on IPs synthesis in non-stimulated and GnRH-treated rat AP cells was examined. MATERIAL AND METHODS In the first experiment 5 × 105 cells/ml were incubated for 3h with VPA (10 nM-10 μM), PMA (100 nM), GnRH (100 nM), PMA (100 nM) + VPA (10 nM-10 μM), GnRH (100 nM) + VPA (10 nM-10 μM). In the second experiment cells were preincubated for 24h with 1μCi myo-[23 H]-inositol, then for 30 min with 10 mM LiCl and finally for 3hr with GnRH (100 nM) VPA (1 μM, 10 μM), GnRH (100 nM) + VPA (1 μM, 10 μM). LH concentration was measured by RIA and intracellular IPs accumulation by ion-exchange chromatography analysis. RESULTS VPA diminished GnRH-stimulated LH release without affecting PMA-induced LH release at any dose tested. Moreover, VPA-induced increase of IPs accumulation occurred in both non-stimulated and GnRH-treated cells and intensity of cellular response was similar in both groups. CONCLUSION VPA affects IP3/PKC pathway activity through its up-regulatory effect on IPs synthesis in AP cells. VPA-induced inhibition of GnRH-stimulated LH release from gonadotrope cells appears to be the result of still unrecognized cellular mechanism.
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15
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Cui L, Li J, Xie X. Rediocide A, an Insecticide, induces G-protein-coupled receptor desensitization via activation of conventional protein kinase C. J Nat Prod 2012; 75:1058-1062. [PMID: 22650618 DOI: 10.1021/np3000359] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In order to identify small-molecule antagonists of Methuselah (Mth), a Drosophila G-protein-coupled receptor (GPCR) involved in life-span control, a library of natural compounds was screened, and it was found that rediocide A (1), a daphnane ester from the roots of Trigonostemon reidioides and used currently for flea control, potently inhibited calcium mobilization mediated by this receptor. Compound 1 inhibited calcium mobilization in GPCRs other than Mth, indicating that the inhibitory effect was not due to receptor antagonism but rather to a more general mechanism. It was found that 1 can induce GPCR desensitization and internalization, and such effects were mediated by the activation of conventional protein kinase C.
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Affiliation(s)
- Lixin Cui
- State Key Laboratory of Drug Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China
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16
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Hing B, Davidson S, Lear M, Breen G, Quinn J, McGuffin P, MacKenzie A. A polymorphism associated with depressive disorders differentially regulates brain derived neurotrophic factor promoter IV activity. Biol Psychiatry 2012; 71:618-26. [PMID: 22265241 PMCID: PMC3712170 DOI: 10.1016/j.biopsych.2011.11.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 11/23/2011] [Accepted: 11/23/2011] [Indexed: 01/12/2023]
Abstract
BACKGROUND Changes in brain derived neurotrophic factor (BDNF) expression have been associated with mood disorders and cognitive dysfunction. Transgenic models that overexpress or underexpress BDNF demonstrate similar deficits in cognition and mood. We explored the hypothesis that BDNF expression is controlled by balancing the activity of BDNF promoter IV (BP4) with a negative regulatory region containing a polymorphism associated with cognitive dysfunction and mood disorders. METHODS We used comparative genomics, transgenic mouse production, and magnetofection of primary neurons with luciferase reporters and signal transduction agonist treatments to identify novel polymorphic cis-regulatory regions that control BP4 activity. RESULTS We show that BP4 is active in the hippocampus, the cortex, and the amygdala and responds strongly to stimuli such as potassium chloride, lithium chloride, and protein kinase C agonists. We also identified a highly conserved sequence 21 kilobase 5' of BP4 that we called BE5.2, which contains rs12273363, a polymorphism associated with decreased BDNF expression, mood disorders, and cognitive decline. BE5.2 modulated the ability of BP4 to respond to different stimuli. Intriguingly, the rarer disease associated allele, BE5.2(C), acted as a significantly stronger repressor of BP4 activity than the more common BE5.2(T) allele. CONCLUSIONS This study shows that the C allele of rs12273363, which is associated with mood disorder, modulates BP4 activity in an allele-specific manner following cell depolarization or the combined activity of protein kinase A and protein kinase C pathways. The relevance of these findings to the role of BDNF misexpression in mood disorders and cognitive decline is discussed.
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Affiliation(s)
- Benjamin Hing
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - Scott Davidson
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - Marrisa Lear
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - Gerome Breen
- Institute of Psychiatry, Kings College London, London, United Kingdom
| | - John Quinn
- Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Peter McGuffin
- Institute of Psychiatry, Kings College London, London, United Kingdom
| | - Alasdair MacKenzie
- School of Medical Sciences, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, Scotland, United Kingdom
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17
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Wyatt TA, Kharbanda KK, McCaskill ML, Tuma DJ, Yanov D, DeVasure J, Sisson JH. Malondialdehyde-acetaldehyde-adducted protein inhalation causes lung injury. Alcohol 2012; 46:51-9. [PMID: 21958604 DOI: 10.1016/j.alcohol.2011.09.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 09/02/2011] [Accepted: 09/06/2011] [Indexed: 01/13/2023]
Abstract
In addition to cigarette smoking, alcohol exposure is also associated with increased lung infections and decreased mucociliary clearance. However, little research has been conducted on the combination effects of alcohol and cigarette smoke on lungs. Previously, we have demonstrated in a mouse model that the combination of cigarette smoke and alcohol exposure results in the formation of a very stable hybrid malondialdehyde-acetaldehyde (MAA)-adducted protein in the lung. In in vitro studies, MAA-adducted protein stimulates bronchial epithelial cell interleukin-8 (IL-8) via the activation of protein kinase C epsilon (PKCɛ). We hypothesized that direct MAA-adducted protein exposure in the lungs would mimic such a combination of smoke and alcohol exposure leading to airway inflammation. To test this hypothesis, C57BL/6J female mice were intranasally instilled with either saline, 30μL of 50μg/mL bovine serum albumin (BSA)-MAA, or unadducted BSA for up to 3 weeks. Likewise, human lung surfactant proteins A and D (SPA and SPD) were purified from human pulmonary proteinosis lung lavage fluid and successfully MAA-adducted in vitro. Similar to BSA-MAA, SPD-MAA was instilled into mouse lungs. Lungs were necropsied and assayed for histopathology, PKCɛ activation, and lung lavage chemokines. In control mice instilled with saline, normal lungs had few inflammatory cells. No significant effects were observed in unadducted BSA- or SPD-instilled mice. However, when mice were instilled with BSA-MAA or SPD-MAA for 3 weeks, a significant peribronchiolar localization of inflammatory cells was observed. Both BSA-MAA and SPD-MAA stimulated increased lung lavage neutrophils and caused a significant elevation in the chemokine, keratinocyte chemokine, which is a functional homologue to human IL-8. Likewise, MAA-adducted protein stimulated the activation of airway and lung slice PKCɛ. These data support that the MAA-adducted protein induces a proinflammatory response in the lungs and that the lung surfactant protein is a biologically relevant target for malondialdehyde and acetaldehyde adduction. These data further implicate MAA-adduct formation as a potential mechanism for smoke- and alcohol-induced lung injury.
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Affiliation(s)
- Todd A Wyatt
- Research Service, Veteran Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA.
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18
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Mooi LY, Yew WT, Hsum YW, Soo KK, Hoon LS, Chieng YC. Suppressive effect of maslinic acid on PMA-induced protein kinase C in human B-lymphoblastoid cells. Asian Pac J Cancer Prev 2012; 13:1177-82. [PMID: 22799301 DOI: 10.7314/apjcp.2012.13.4.1177] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Protein kinase C (PKC) has been implicated in carcinogenesis and displays variable expression profiles during cancer progression. Studies of dietary phytochemicals on cancer signalling pathway regulation have been conducted to search for potent signalling regulatory agents. The present study was designed to evaluate any suppressive effect of maslinic acid on PKC expression in human B-lymphoblastoid cells (Raji cells), and to identify the PKC isoforms expressed. Effects of maslinic acid on PKC activity were determined using a PepTag assay for non-radioactive detection of PKC. The highest expression in Raji cells was obtained at 20 nM PMA induced for 6 hours. Suppressive effects of maslinic acid were compared with those of four PKC inhibitors (H- 7, rottlerin, sphingosine, staurosporine) and two triterpenes (oleanolic acid and ursolic acid). The IC₅₀ values achieved for maslinic acid, staurosporine, H-7, sphingosine, rottlerin, ursolic acid and oleanolic acid were 11.52, 0.011, 0.767, 2.45, 5.46, 27.93 and 39.29 μM, respectively. Four PKC isoforms, PKC βI, βII, δ, and ζ, were identified in Raji cells via western blotting. Maslinic acid suppressed the expression of PKC βI, δ, and ζ in a concentration-dependent manner. These preliminary results suggest promising suppressive effects of maslinic acid on PKC activity in Raji cells. Maslinic acid could be a potent cancer chemopreventive agent that may be involved in regulating many downstream signalling pathways that are activated through PKC receptors.
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Affiliation(s)
- Lim Yang Mooi
- Department of Pre-clinical Science, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman, Selangor, Malaysia.
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Kao HH, Wu CJ, Won SJ, Shin JW, Liu HS, Su CL. Kinase gene expression and subcellular protein expression pattern of protein kinase C isoforms in curcumin-treated human hepatocellular carcinoma Hep 3B cells. Plant Foods Hum Nutr 2011; 66:136-142. [PMID: 21556896 DOI: 10.1007/s11130-011-0228-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Curcumin, a yellow component of turmeric or curry powder, has been demonstrated to exhibit anti-carcinogenic effects in vitro, in vivo, and in human clinical trials. One of its molecular targets is protein kinase C (PKC) which has been reported to play essential roles in apoptosis, cell proliferation, and carcinogenesis. In this study, PKC mRNA expression was significantly inhibited in curcumin-treated human hepatocellular carcinoma (HCC) Hep 3B cells identified using a kinase cDNA microarray. Furthermore, curcumin decreased total protein expression of all PKCs in a time-related manner by immunoblotting of whole cell lysates, nuclear, membrane, and cytosolic fractions. In cytosolic fraction, the expression of PKC-α was totally inhibited by curcumin. In contrast, the expression levels of PKC-ζ and -μ were dramatically increased. Increases in expression of PKC-δ and PKC-ζ in the membrane and nucleus, and PKC-ι in the membrane were detected. In summary, the changes in expression and distribution of subcellular PKC isoforms in curcumin-treated Hep 3B cells suggest possible PKC-associated anti-tumor mechanisms of curcumin and provide alternative therapies for human HCC.
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Affiliation(s)
- Hsin-Hsin Kao
- Department of Food Nutrition, Chung Hwa University of Medical Technology, No. 89, Wen-Hwa 1st Street, Jen-Te, Tainan, 717, Taiwan
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Koskinen A, Vuolteenaho K, Nieminen R, Moilanen T, Moilanen E. Leptin enhances MMP-1, MMP-3 and MMP-13 production in human osteoarthritic cartilage and correlates with MMP-1 and MMP-3 in synovial fluid from OA patients. Clin Exp Rheumatol 2011; 29:57-64. [PMID: 21345293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 10/18/2010] [Indexed: 05/30/2023]
Abstract
OBJECTIVES In the present study, we investigated the role of adipocytokine leptin in the pathogenesis of osteoarthritis (OA) by measuring its effects on matrix metalloproteinase (MMP) production in human OA cartilage. In addition, the correlations between leptin and MMP concentrations in synovial fluid from OA patients were studied. METHODS Cartilage tissue obtained from leftover pieces of total knee replacement surgery from patients with OA was used in the experiments. Production of collagenases MMP-1, MMP-8 and MMP-13, and stromelysin-1 (MMP-3) in the cartilage was measured by immunoassay and the signalling pathways were explored by pharmacological means. In addition, synovial fluid samples were collected from 84 OA patients undergoing knee replacement surgery. The concentrations of leptin and MMPs in synovial fluid were measured by immunoassay. RESULTS Leptin alone and in combination with IL-1β enhanced production of MMP-1, MMP-3, and MMP-13 in human OA cartilage, while MMP-8 concentrations remained undetectable. The effects of leptin on MMP-1, MMP-3 and MMP-13 production were mediated through transcription factor NF-κβ, and through protein kinase C and MAP kinase pathways. Interestingly, leptin concentrations in synovial fluid from OA patients correlated positively with MMP-3 (r=0.51, p<0.001) and MMP-1 (r=0.41, p<0.001) levels. CONCLUSIONS To our knowledge, this is the first study to show that leptin up-regulates MMP-1 and MMP-3 production in human OA cartilage and correlates positively to MMP-1 and MMP-3 in synovial fluid from OA patients. The findings suggest that leptin has catabolic effects in OA joints by increasing MMP production in cartilage.
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Affiliation(s)
- Anna Koskinen
- The Immunopharmacology Research Group, Tampere University Hospital, Tampere, Finland.
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Chen CY, Yang YH, Kuo SY. Effect of [6]-shogaol on cytosolic Ca2+ levels and proliferation in human oral cancer cells (OC2). J Nat Prod 2010; 73:1370-1374. [PMID: 20669930 DOI: 10.1021/np100213a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The effect of [6]-shogaol (1) on cytosolic free Ca(2+) concentrations ([Ca(2+)](i)) and viability has not been explored previously in oral epithelial cells. The present study has examined whether 1 alters [Ca(2+)](i) and viability in OC2 human oral cancer cells. Compound 1 at concentrations > or = 5 microM increased [Ca(2+)](i) in a concentration-dependent manner with a 50% effective concentration (EC(50)) value of 65 microM. The Ca(2+) signal was reduced substantially by removing extracellular Ca(2+). In a Ca(2+)-free medium, the 1-induced [Ca(2+)](i) elevation was mostly attenuated by depleting stored Ca(2+) with thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor). The [Ca(2+)](i) signal was inhibited by La(3+) but not by L-type Ca(2+) channel blockers. The elevation of [Ca(2+)](i) caused by 1 in a Ca(2+)-containing medium was not affected by modulation of protein kinase C activity, but was inhibited by 82% with the phospholipase A2 inhibitor aristolochic acid I (20 microM). U73122, a selective inhibitor of phospholipase C, abolished 1-induced [Ca(2+)](i) release. At concentrations of 5-100 microM, 1 killed cells in a concentration-dependent manner. These findings suggest that [6]-shogaol induces a significant rise in [Ca(2+)](i) in oral cancer OC2 cells by causing stored Ca(2+) release from the thapsigargin-sensitive endoplasmic reticulum pool in an inositol 1,4,5-trisphosphate-dependent manner and by inducing Ca(2+) influx via a phospholipase A2- and La(3+)-sensitive pathway.
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Affiliation(s)
- Chung-Yi Chen
- Department of Medical Technology, School of Medical and Health Sciences, Fooyin University, Ta-liao, Kaohsiung County 83101, Taiwan, Republic of China
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Doi T, Puri P, Bannigan J, Thompson J. Disruption of noncanonical Wnt/CA2+ pathway in the cadmium-induced omphalocele in the chick model. J Pediatr Surg 2010; 45:1645-9. [PMID: 20713214 DOI: 10.1016/j.jpedsurg.2009.11.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 11/23/2009] [Accepted: 11/26/2009] [Indexed: 12/11/2022]
Abstract
PURPOSE Cadmium (Cd) has been found to cause ventral body wall defects (VBWDs) in the chick embryo similar to human omphalocele. The earliest detectable histologic changes in Cd-induced VBWD chick model have been observed 4 hours posttreatment. The exact mechanism by which Cd acts in the early embryogenesis remains unclear. Wnt proteins play a key role during embryogenesis, and altered Wnt signaling has been linked to developmental defects. Noncanonical Wnt/Ca(2+) pathway has been implicated in regulating embryogenesis by controlling cell movement and adhesion. Wnt11 can activate protein kinase C (PKC) and calcium/calmodulin-dependent kinase II (CaMKII) in the Wnt/Ca(2+) pathway. We hypothesized that the Wnt11, PKCalpha, and CaMKII gene expression is downregulated in the Cd-induced VBWD during early embryogenesis. METHODS After 60 hours of incubation, chick embryos were harvested 1 hour (1H), 4H, and 8H after treatment of saline or cadmium and divided into 2 groups: control and Cd (n = 8 at each time-point, respectively). Real-time polymerase chain reaction was performed to evaluate the messenger RNA (mRNA) expression of Wnt11, PKCalpha, and CaMKII in the Cd-induced VBWD chick model. RESULTS The mRNA expression levels of Wnt11, PKCalpha, and CaMKII were significantly decreased at 1H in Cd group compared to controls (P < .05). However, there were no significant differences in the other time-points. CONCLUSION Downregulation of Wnt11, PKCalpha, and CaMKII gene expression during the narrow window of early embryogenesis may cause VBWD, interfering with cell movement and adhesion, disrupting Wnt/Ca(2+) pathway.
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Affiliation(s)
- Takashi Doi
- The Children's Research Center, Our Lady's Children's Hospital, Dublin, Ireland
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23
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Wang JZ, Cai CY, Zhang YM, Zheng JH, Chen YC, Li WQ, Shi GG. N-n-Butyl haloperidol iodide protects against hypoxia/reoxygenation-induced cardiomyocyte injury by modulating protein kinase C activity. Biochem Pharmacol 2010; 79:1428-36. [PMID: 20105432 DOI: 10.1016/j.bcp.2010.01.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2009] [Revised: 01/04/2010] [Accepted: 01/19/2010] [Indexed: 02/05/2023]
Abstract
N-n-Butyl haloperidol iodide (F2), a novel compound derived from haloperidol, protects against the damaging effects of ischemia/reperfusion (I/R) injury in vitro and in vivo. We tested whether the myocardial protection of F2 on cardiomyocyte hypoxia/reoxygenation (H/R) injury is mediated by modulating protein kinase C (PKC) activity in primary cultured cardiomyocytes. Primary cultures of ventricular cardiomyocytes underwent 2-h hypoxia and 30-min reoxygenation. Total PKC activity was measured, and the translocation pattern of PKCalpha, betaII, delta and epsilon isoforms was assessed by fractionated western blot analysis. We investigated the association of PKC isoform translocation and H/R-induced injury in the presence and absence of the specific inhibitors and activator. Measurements included cell damage evaluated by creatine kinase (CK) release, and apoptosis measured by annexin V-FITC assay. In primary cultured cardiomyocytes exposed to H/R, PKCalpha, delta and epsilon were translocated, with no change in PKCbetaII activity. Total PKC activity, CK release and apoptosis were increased after H/R. Treatment with the conventional PKC inhibitor Go6976 reduced early growth response-1 (Egr-1) protein expression and attenuated apoptosis. The PKCepsilon inhibitor peptide epsilonV1-2 increased H/R injury without influencing Egr-1 expression. Pretreatment with F2 inhibited translocation of PKCalpha, increased translocation of PKCepsilon, and relieved the CK release and apoptosis. The protection of F2 was blocked in part by the conventional PKC activator thymeleatoxin (TXA) and epsilonV1-2 peptide. F2 significantly alleviated H/R-induced injury, which might be attributed to the combined benefits of inhibiting PKCalpha and activating PKCepsilon.
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Affiliation(s)
- Jin-Zhi Wang
- Department of Pharmacology, Shantou University Medical College, PR China
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Nakamura K, Tachikawa Y, Ohno O, Kitamura M, Suganuma M, Uemura D. Neocomplanines A and B, a complanine family isolated from the marine fireworm. J Nat Prod 2010; 73:303-305. [PMID: 20028030 DOI: 10.1021/np900694j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Two new members of the complanine family, neocomplanines A (2) and B (3), were isolated as minor components of the methanolic extract of the "marine fireworm" Eurythoe complanata. The structures of the neocomplanines were revealed spectroscopically to be a trimethylammonium unit with a saturated carbon chain. The planar structures of neocomplanines A and B were confirmed successfully through total syntheses that used epichlorohydrin as a starting material. The neocomplanines show inflammatory activity and also enhanced PKC activity in combination with TPA in the presence of Ca(2+) in vitro; both are similar to the effects of complanine (1). The molecular mechanism of the effects of complanine-related compounds is discussed.
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Affiliation(s)
- Kazuhiko Nakamura
- Department of Biosciences and Informatics, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522, Japan
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Sajan MP, Bandyopadhyay G, Miura A, Standaert ML, Nimal S, Longnus SL, Van Obberghen E, Hainault I, Foufelle F, Kahn R, Braun U, Leitges M, Farese RV. AICAR and metformin, but not exercise, increase muscle glucose transport through AMPK-, ERK-, and PDK1-dependent activation of atypical PKC. Am J Physiol Endocrinol Metab 2010; 298:E179-92. [PMID: 19887597 PMCID: PMC2822478 DOI: 10.1152/ajpendo.00392.2009] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Activators of 5'-AMP-activated protein kinase (AMPK) 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR), metformin, and exercise activate atypical protein kinase C (aPKC) and ERK and stimulate glucose transport in muscle by uncertain mechanisms. Here, in cultured L6 myotubes: AICAR- and metformin-induced activation of AMPK was required for activation of aPKC and ERK; aPKC activation involved and required phosphoinositide-dependent kinase 1 (PDK1) phosphorylation of Thr410-PKC-zeta; aPKC Thr410 phosphorylation and activation also required MEK1-dependent ERK; and glucose transport effects of AICAR and metformin were inhibited by expression of dominant-negative AMPK, kinase-inactive PDK1, MEK1 inhibitors, kinase-inactive PKC-zeta, and RNA interference (RNAi)-mediated knockdown of PKC-zeta. In mice, muscle-specific aPKC (PKC-lambda) depletion by conditional gene targeting impaired AICAR-stimulated glucose disposal and stimulatory effects of both AICAR and metformin on 2-deoxyglucose/glucose uptake in muscle in vivo and AICAR stimulation of 2-[(3)H]deoxyglucose uptake in isolated extensor digitorum longus muscle; however, AMPK activation was unimpaired. In marked contrast to AICAR and metformin, treadmill exercise-induced stimulation of 2-deoxyglucose/glucose uptake was not inhibited in aPKC-knockout mice. Finally, in intact rodents, AICAR and metformin activated aPKC in muscle, but not in liver, despite activating AMPK in both tissues. The findings demonstrate that in muscle AICAR and metformin activate aPKC via sequential activation of AMPK, ERK, and PDK1 and the AMPK/ERK/PDK1/aPKC pathway is required for metformin- and AICAR-stimulated increases in glucose transport. On the other hand, although aPKC is activated by treadmill exercise, this activation is not required for exercise-induced increases in glucose transport, and therefore may be a redundant mechanism.
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Affiliation(s)
- M. P. Sajan
- 1Research Service, James A. Haley Veterans Hospital and Department of Internal Medicine, University of South Florida College of Medicine, Tampa, Florida;
| | - G. Bandyopadhyay
- 1Research Service, James A. Haley Veterans Hospital and Department of Internal Medicine, University of South Florida College of Medicine, Tampa, Florida;
| | - A. Miura
- 1Research Service, James A. Haley Veterans Hospital and Department of Internal Medicine, University of South Florida College of Medicine, Tampa, Florida;
| | - M. L. Standaert
- 1Research Service, James A. Haley Veterans Hospital and Department of Internal Medicine, University of South Florida College of Medicine, Tampa, Florida;
| | - S. Nimal
- 6Roskamp Institute, Sarasota, Florida
| | - S. L. Longnus
- 2Institut National de la Santé et de la Recherche Médicale (INSERM) U145, Institut Federatif de Recherche 50, Faculte de Medicine, Nice and
| | - E. Van Obberghen
- 2Institut National de la Santé et de la Recherche Médicale (INSERM) U145, Institut Federatif de Recherche 50, Faculte de Medicine, Nice and
| | - I. Hainault
- 3INSERM U671, Centre de Recherches Biomedicales des Cordeliers, Universite Pierre et Marie Curie, Paris, France;
| | - F. Foufelle
- 3INSERM U671, Centre de Recherches Biomedicales des Cordeliers, Universite Pierre et Marie Curie, Paris, France;
| | - R. Kahn
- 4Joslin Center and Harvard Medical School, Boston, Massachusetts;
| | - U. Braun
- 5Biotechnology Centre of Oslo, Oslo, Norway; and
| | - M. Leitges
- 5Biotechnology Centre of Oslo, Oslo, Norway; and
| | - R. V. Farese
- 1Research Service, James A. Haley Veterans Hospital and Department of Internal Medicine, University of South Florida College of Medicine, Tampa, Florida;
- 6Roskamp Institute, Sarasota, Florida
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Sato K, Iemitsu M, Aizawa K, Ajisaka R. DHEA improves impaired activation of Akt and PKC zeta/lambda-GLUT4 pathway in skeletal muscle and improves hyperglycaemia in streptozotocin-induced diabetes rats. Acta Physiol (Oxf) 2009; 197:217-25. [PMID: 19523145 DOI: 10.1111/j.1748-1716.2009.02011.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIM Addition of dehydroepiandrosterone (DHEA) to a cultured skeletal muscle locally synthesizes 5alpha-dihydrotestosterone (DHT). It induced activation of glucose metabolism-related signalling pathway via protein kinase B (Akt) and protein kinase C zeta/lambda (PKC zeta/lambda)-glucose transporter-4 (GLUT4) proteins. However, such an effect of DHEA in vivo remains unclear. METHODS Using streptozotocin (STZ)-induced rats with type 1 diabetes mellitus, we tested the hypothesis that a single bout of DHEA injection in the rats improves hyperglycaemia and muscle GLUT4-regulated signalling pathway. After 1 week of STZ injection (55 mg kg(-1)) with male Wistar rats, fasting glucose concentrations were determined in a blood sample taken from the tail vein. Blood glucose levels were then monitored for 180 min after DHEA or sesame oil (control) was injected (n = 10 for each group). RESULTS Blood glucose levels decreased significantly for 30-150 min after 2 mg DHEA injection in the STZ rats. In the skeletal muscle, expression and translocation of GLUT4 protein, phosphorylation of Akt and PKC zeta/lambda, and phosphofructokinase and hexokinase enzyme activities increased significantly by DHEA injection. However, DHEA-induced improvements in Akt and PKC zeta/lambda-GLUT4 pathways were blocked by a DHT inhibitor. CONCLUSION These results suggest that a single bout of DHEA injection can improve hyperglycaemia and activate the glucose metabolism-related signalling pathway via Akt and PKC zeta/lambda-GLUT4 proteins of skeletal muscles in rats. Moreover, these results show that a DHEA-induced increase in muscle glucose uptake and utilization might contribute to improvement in hyperglycaemia in type 1 diabetes mellitus.
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Affiliation(s)
- K Sato
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
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Abdullayeva R, Ganiyev M, Asmetov V. Effects of diumancal and decursinol on 5-hydroxytryptamine level in rat brain. Georgian Med News 2009:84-88. [PMID: 19801740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In an attempt to elucidate whether changes in serotonin (5-HT) levels were involved in the behavioral changes, monoamine concentrations in three brain regions (striatum, frontal cortex and hypothalamus) obtained from diumancal (0,1 mg/kg;1 mg/kg) and decursinol (1mg/kg;10mg/kg) -treated rats were quantified by spectrofluorometer, and compared with monoamine concentrations in verapamil-treated animals (2 mg/kg; 15 mg/kg). It was found that both 2H1 benzopyrane 2-on derivatives diumancal and decursinol, a novel calcium antagonists increase 5-HT levels in three brain regions as verapamil does. The highest concentration of serotonin was observed in frontal cortex and striatum after administration of 10 mg/kg-dose decursinol. Diumancal at high dose (1 mg/kg) increased the level of neurotransmitter more remarkably in hypothalamus. Taking into account the activating effect of diumancal and decursinol on serotonergic system they may have a place in the treatment of some depressive disorders. More detailed investigations are required though.
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Affiliation(s)
- R Abdullayeva
- Department of Pharmacology, Azerbaijan Medical University, Baku, Azerbaijan
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Moldovan SM, Nervina JM, Tetradis S, Camargo PM. Regulation of Nur77 gene expression by prostanoids in cementoblastic cells. Arch Oral Biol 2009; 54:412-9. [PMID: 19237150 DOI: 10.1016/j.archoralbio.2009.01.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 12/18/2008] [Accepted: 01/26/2009] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The inflammatory cytokine interleukin-1 (IL-1) decreases mineralisation by immortalized mouse-derived cementoblastic cells (OC-CM cells), whilst various prostanoids, including fluprostenol (flup) increase it. Subtraction hybridisation conducted on flup minus IL-1-treated OC-CM cells revealed that one of the primary response genes preferentially induced by flup is the transcription factor Nur77. The objective of this study was to examine the signal transduction cascades regulating prostanoid induction of Nur77 gene expression in OC-CM cells. METHODS Confluent OC-CM cells were treated with prostaglandin E(2) (PGE(2)), prostaglandin F(2alpha) (PGF(2alpha)), specific activators of the various EP prostanoid receptors and of the FP prostanoid receptor, and direct activators/inhibitors of the cyclic AMP-protein kinase A (PKA), protein kinase C (PKC) and intracellular calcium pathways. Nur77 gene expression was examined by mRNA extraction and Northern blot analysis. RESULTS PGE(2) and PGF(2alpha) treatment of OC-CM cells significantly increased Nur77 mRNA expression in a time- and dose-dependent fashion. Both the EP1 prostanoid receptor-specific activator 16,16-dimethyl-PGE(2) and the FP prostanoid receptor-specific activator flup significantly increased Nur77 gene expression by OC-CM cells as compared to vehicle-treated controls. Increase in Nur77 gene expression was also observed when direct activators of the PKA, PKC and intracellular calcium pathways were used to treat OC-CM cells. Direct inhibition of the PKA, PKC and intracellular calcium pathways abrogated Nur77 gene expression induced by OC-CM cell treatment with PGE(2) and PGF(2alpha). CONCLUSION Nur77 is a primary gene expressed by OC-CM cells and its induction appears to be mediated by the PKA, PKC and intracellular calcium pathways. Nur77 may affect expression of downstream target genes in OC-CM cells and partially regulate cementoblast cell function.
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Affiliation(s)
- Sanda M Moldovan
- Division of Associated Clinical Specialties, Section of Periodontics, School of Dentistry, University of California, Los Angeles, CA 90095, United States
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Roh DH, Kim HW, Yoon SY, Seo HS, Kwon YB, Kim KW, Han HJ, Beitz AJ, Lee JH. Intrathecal administration of sigma-1 receptor agonists facilitates nociception: involvement of a protein kinase C-dependent pathway. J Neurosci Res 2008; 86:3644-54. [PMID: 18655205 DOI: 10.1002/jnr.21802] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Sigma sites, originally proposed as opioid receptor subtypes, are currently thought to represent unique receptors with a specific pattern of drug selectivity, a well-established anatomical distribution and broad range of functional roles including potential involvement in nociceptive mechanisms. We have recently demonstrated that intrathecal (i.t.) treatment with a sigma-1 receptor antagonist reduced formalin-induced pain behavior. In the present study, we investigated the potential role of spinal sigma-1 receptor agonists in peripherally initiated nociception and attempted to elucidate intracellular signaling mechanisms associated with spinal cord sigma-1 receptor activation in mice. The i.t. injection of the sigma-1 receptor agonists PRE-084 (PRE) or carbetapentane (CAR) significantly decreased tail-flick latency (TFL) and increased the frequency of paw withdrawal responses to mechanical stimulation (von Frey filament, 0.6 g) as well as the amount of Fos expression in the spinal cord dorsal horn induced by noxious paw-pinch stimulation. These PRE- or CAR-induced facilitatory effects on nociception were significantly blocked by i.t. pretreatment with the sigma-1 receptor antagonist, BD-1047, the phospholipase C (PLC) inhibitor, U-73,122, the Ca(2+)-ATPase inhibitor, thapsigargin, and the protein kinase C (PKC) inhibitor, chelerythrine. Western blot analysis further revealed that i.t. PRE or CAR injection significantly increased pan-PKC as well as the PKCalpha, epsilon, and zeta isoforms in the dorsal horn. Collectively, these findings demonstrate that calcium-dependent second messenger cascades including PKC are involved in the facilitation of nociception associated with spinal sigma-1 receptor activation.
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Affiliation(s)
- Dae-Hyun Roh
- Department of Veterinary Physiology, College of Veterinary Medicine and BK21 Program for Veterinary Science, Seoul National University, Seoul, South Korea
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Gatti R, Andre E, Barbara C, Dinh TQ, Fontana G, Fischer A, Geppetti P, Trevisani M. Ethanol potentiates the TRPV1-mediated cough in the guinea pig. Pulm Pharmacol Ther 2008; 22:33-6. [PMID: 19049892 DOI: 10.1016/j.pupt.2008.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 10/29/2008] [Accepted: 11/04/2008] [Indexed: 10/21/2022]
Abstract
Ethanol is a chemical irritant able to induce a large variety of effects in the airways. It has been reported that ethanol sensitizes the transient receptor potential vanilloid-1 (TRPV1) to various stimuli and inhalation of ethanol enhances the cough mediated by TRPV1 activation (capsaicin) in patients suffering of airway sensory hyperreactivity. Here, we set out to investigate whether ethanol sensitizes the cough induced by TRPV1 activation in a guinea pig model and the possible mechanism of such exacerbating effect. Aerosolized resiniferatoxin (RTX, 0.5 microM) and hypertonic saline (7%) produced a cough response dependent and independent of TRPV1 activation, respectively. Ethanol (3%, 10 min) inhalation, that per se did not cause any tussive response, significantly increased the number of coughs evoked by RTX inhalation without affecting hypertonic saline (7%) induced cough. Potentiation by ethanol of the tussive response to RTX was prevented by the PKC inhibitor, GF109203X (GFX). In conclusion, ethanol selectively exaggerates, via a PKC-dependent pathway, the cough response evoked by TRPV1 stimulation. The present results may contribute to explain respiratory distresses sometimes associated to alcohol consumption, including cough and asthma.
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Affiliation(s)
- Raffaele Gatti
- Department of Clinical and Experimental Medicine, Pharmacology Section, University of Ferrara, 44100 Ferrara, Italy.
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Eriksson TL, Svensson SPS, Lundström I, Persson K, Andersson TPM, Andersson RGG. Panax ginseng induces anterograde transport of pigment organelles in Xenopus melanophores. J Ethnopharmacol 2008; 119:17-23. [PMID: 18639398 DOI: 10.1016/j.jep.2008.05.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Revised: 05/19/2008] [Accepted: 05/22/2008] [Indexed: 05/26/2023]
Abstract
Melanophores from Xenopus laevis are pigmented cells, capable of quick colour changes through cyclic adenosine 3':5'-monophosphate (cAMP) coordinated transport of their intracellular pigment granules, melanosomes. In this study we use the melanophore cell line to evaluate the effects of Panax ginseng extract G115 on organelle transport. Absorbance readings of melanophore-coated microplates, Correlate-EIA direct cAMP enzyme immunoassay kit, and western blot were used to measure the melanosome movement and changes in intracellular signalling. We show that Panax ginseng induces a fast concentration-dependent anterograde transport of the melanosomes. No significant increase in the cAMP level was seen and pre-incubation of melanophores with the protein kinase C (PKC) inhibitor EGF-R Fragment 651-658 (M-EGF) only partly decreased the ginseng-induced dispersion. We also demonstrate that Panax ginseng, endothelin-3 (ET-3) and alpha-melanocyte stimulating hormone (MSH) stimulate an activation of mitogen activated protein kinase (MAPK). Pre-incubation with M-EGF decreased the MAPK activity induced by ET-3 and MSH, but again only marginally affected the response of Panax ginseng. Thus, in melanophores we suggest that Panax ginseng stimulates an anterograde transport of pigment organelles via a non-cAMP and mainly PKC-independent pathway.
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Affiliation(s)
- Therese L Eriksson
- Division of Drug Research/Pharmacology, Department of Medical and Health Sciences, Linköping University, SE-581 85 Linköping, Sweden.
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Esmaeili-Mahani S, Shimokawa N, Javan M, Maghsoudi N, Motamedi F, Koibuchi N, Ahmadiani A. Low-dose morphine induces hyperalgesia through activation of G alphas, protein kinase C, and L-type Ca 2+ channels in rats. J Neurosci Res 2008; 86:471-9. [PMID: 17893922 DOI: 10.1002/jnr.21489] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Opioids can induce analgesia and also hyperalgesia in humans and in animals. It has been shown that systemic administration of morphine induced a hyperalgesic response at an extremely low dose. However, the exact mechanism(s) underlying opioid-induced hyperalgesia has not yet been clarified. Here, we have investigated cellular events involved in low-dose morphine hyperalgesia in male Wistar rats. The data showed that morphine (0.01 microg i.t.) could elicit hyperalgesia as assessed by the tail-flick test. G(alphas) mRNA and protein levels increased significantly following exposure to the hyperalgesic dose of morphine. Furthermore, morphine at an analgesic dose (20 microg i.t.) significantly decreased cAMP levels in the dorsal half of the lumbar spinal cord, whereas the tissue cAMP levels were not affected by morphine treatment at a hyperalgesic dose. Intrathecal administration of nifedipine, an L-type calcium channel blocker, antagonized the hyperalgesia induced by the low-dose of morphine. Furthermore, pretreatment with the selective protein kinase C (PKC) inhibitor chelerytrine resulted in prevention of the morphine-induced hyperalgesia. KT 5720, a specific inhibitor of protein kinase A (PKA), did not show any effect on low-dose morphine-induced hyperalgesia. These results indicate a role for G(alphas), the PLC-PKC pathway, and L-type calcium channels in intrathecal morphine-induced hyperalgesia in rats. Activation of ordinary G(alphas) signaling through cAMP levels did not appear to play a major role in the induction of hyperalgesia by low-dose of morphine.
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Affiliation(s)
- Saeed Esmaeili-Mahani
- Department of Physiology, Neuroscience Research Center, Shahid Beheshti Medical University, Tehran, Iran
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Garg R, Ramchandani AG, Maru GB. Curcumin decreases 12-O-tetradecanoylphorbol-13-acetate-induced protein kinase C translocation to modulate downstream targets in mouse skin. Carcinogenesis 2008; 29:1249-57. [PMID: 18477648 DOI: 10.1093/carcin/bgn114] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Curcumin has been shown to inhibit 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced tumour promotion and some of the TPA-responsive markers in mouse skin. However, its mechanism of action is not fully elucidated. The present study focuses on understanding the role of protein kinase C (PKC), the major cellular receptor of TPA, in mediating TPA-induced biological responses in mouse skin and subsequently, elucidating the effects of curcumin on PKC and its downstream target molecules. As compared with controls, single topical application of TPA (5 nmol) to skin increased the translocation of PKC from cytosolic to particulate fraction, determined in terms of activity and protein levels. Ro-31- 8220 (PKC inhibitor, 1 nmol) when applied topically, alone or prior to TPA, inhibited PKC activity in both the compartments but did not affect the TPA-induced protein translocation. In contrast, though curcumin (10 mumol) alone did not alter the basal activity/levels, its pre-treatment decreased the TPA-induced translocation of PKC isozymes (alpha, beta, gamma, epsilon, eta), resulting in appropriate alterations in activity. Despite differences in modes of action of Ro-31-8220 (activity inhibition) and curcumin (decreasing translocation) in modulating PKC, their pre-treatment blunted the TPA-induced levels of mitogen-activated protein kinases and transcription factors (c-jun, c-fos and nuclear factor-kappa B) and downstream target proteins associated with cell proliferation (cyclin D1 and ornithine decarboxylase), cell death (Bax and Bcl2), inflammation (cyclooxygenase-2 and prostaglandin E2) and oxidative stress (8-hydroxy-2'-deoxyguanosine) in skin. These results demonstrate the crucial role of PKC in TPA-mediated cellular responses in skin and that curcumin modulates transmembrane signal transduction via PKC to affect TPA-induced biochemical and molecular alterations in mouse skin.
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Affiliation(s)
- Rachana Garg
- Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi Mumbai 410 208, India
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Rajagopal S, Fang H, Patanavanich S, Sando JJ, Kamatchi GL. Protein kinase C isozyme-specific potentiation of expressed Ca v 2.3 currents by acetyl-beta-methylcholine and phorbol-12-myristate, 13-acetate. Brain Res 2008; 1210:1-10. [PMID: 18420182 DOI: 10.1016/j.brainres.2008.03.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Accepted: 03/07/2008] [Indexed: 11/18/2022]
Abstract
Protein kinase C (PKC) is implicated in the potentiation of Ca v 2.3 currents by acetyl-beta-methylcholine (MCh), a muscarinic M1 receptor agonist or phorbol-12-myristate, 13-acetate (PMA). The PKC isozymes responsible for the action of MCh and PMA were investigated using translocation as a measure of activation and with isozyme-selective antagonists and siRNA. Ca v channels were expressed with alpha1 2.3, beta1b and alpha2delta subunits and muscarinic M1 receptors in the Xenopus oocytes and the expressed currents (I Ba) were studied using Ba2+ as the charge carrier. Translocation of PKC isozymes to the membrane studied by Western blot revealed that all eleven known PKC isozymes are present in the Xenopus oocytes. Exposure of the oocytes to MCh led to the translocation of PKC alpha whereas PMA activated PKC betaII and epsilon isozymes. The action of MCh was inhibited by Go 6976, an inhibitor of cPKC isozymes or PKC alpha siRNA. PMA-induced potentiation of Ca v 2.3 currents was inhibited by CG533 53, a PKC betaII antagonist, betaIIV5.3, a peptide translocation inhibitor of PKC betaII or PKC betaII siRNA. Similarly, epsilonV1.2, a peptide translocation inhibitor of PKC epsilon or PKC epsilon siRNA inhibited PMA action. The inhibitors of PKC increased the basal I Ba slightly. It is possible that some PKC isozymes have negative control over the I Ba. Our results implicate PKC alpha in the potentiation of Ca v 2.3 currents by MCh and PKC betaII and epsilon in the potentiation of Ca v 2.3 currents by PMA.
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Affiliation(s)
- Senthilkumar Rajagopal
- Department of Anesthesiology, P.O. Box 800710, University of Virginia Health Science Systems, 1766 Lane Road, Charlottesville, VA 22908-0710, USA
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Herbst RS, Oh Y, Wagle A, Lahn M. Enzastaurin, a protein kinase Cbeta- selective inhibitor, and its potential application as an anticancer agent in lung cancer. Clin Cancer Res 2007; 13:s4641-6. [PMID: 17671157 DOI: 10.1158/1078-0432.ccr-07-0538] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Enzastaurin, an oral serine/threonine kinase inhibitor, suppresses signaling through protein kinase C (PKC)-beta and the phosphatidylinositol 3-kinase/AKT pathway to induce tumor cell apoptosis, reduce proliferation, and suppress tumor-induced angiogenesis. In contrast to previous PKC inhibitors, enzastaurin is very well tolerated with a favorable safety profile, allowing it to be dosed for extended durations. In the present review, we summarize the rationale for targeting PKC in cancer, the preclinical experience of enzastaurin, and the clinical findings of the current phase I and II studies. Based on the combined information, we present the rationale for its future assessment in the treatment of lung cancer.
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Affiliation(s)
- Roy S Herbst
- M. D. Anderson Cancer Center, Houston, University of Texas, Houston, TX 77030-4009, USA.
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Zhu X, Liu Y, Liu S, Diao F, Xu R, Ni X. Lipopolysaccharide primes macrophages to increase nitric oxide production in response to Staphylococcus Aureus. Immunol Lett 2007; 112:75-81. [PMID: 17686532 DOI: 10.1016/j.imlet.2007.06.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Revised: 06/28/2007] [Accepted: 06/28/2007] [Indexed: 10/23/2022]
Abstract
Sepsis, the leading cause of death in intensive care units, is associated with overproduction of nitric oxide (NO). The mechanism concerning the NO production in the sepsis caused by both Gram-negative and Gram-positive bacteria is largely unknown. The present study examines the effect of lipopolysaccharide (LPS) on Staphylococcus aureus-induced NO production in macrophages. In the naïve murine macrophage cell line RAW264.7, heat-killed Staphylococcus aureus (HKSa) induced a significant NO production at a high concentration (100 microg/ml). However, pretreatment of the cells with increasing concentration of LPS (10-50 ng/ml) resulted in induction of NO production by HKSa even at the doses of 1 and 10 microg/ml. The expression of inducible NO synthase (iNOS) in response to HKSa was also enhanced by LPS pretreatment, suggesting that LPS priming NO production is due to the enhancement of iNOS expression. We examined whether protein kinase C (PKC), mitogen-activated protein kinases (MAPKs) and calcineurin signaling pathways are involved in the priming effects of LPS. It was found that the PKC inhibitor Gö6976, the p38 inhibitor SB203580 and the calcineurin inhibitor cyclosporine A significantly reversed the priming effects of LPS on HKSa-induced NO production and iNOS expression. In contrast, the ERK1/2 inhibitor PD98059 did not block the induction of priming by LPS. These data support the hypothesis that LPS primes macrophages for enhancement of HKSa-induced NO production, and indicate that PKC, p38 and calcineurin might be involved in the LPS-induced priming.
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Affiliation(s)
- Xiaoyan Zhu
- Department of Physiology, Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, PR China
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Jos A, Segner H, Herradón B, Repetto G, Navas JM. Induction of EROD activity by 1-phenylimidazole and β-naphthoflavone in rainbow trout cultured hepatocytes: A comparative study. Toxicol In Vitro 2007; 21:1307-10. [PMID: 17521864 DOI: 10.1016/j.tiv.2007.03.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2006] [Revised: 02/22/2007] [Accepted: 03/25/2007] [Indexed: 11/30/2022]
Abstract
The classical pathway for induction of cytochrome P4501A (CYP1A) by xenobiotics is ligand binding to the aryl hydrocarbon receptor (AhR). However, several studies with mammalian cell systems point out a range of xenobiotics including imidazole derivatives, which are able to activate CYP1A through non-classical mechanisms. The objective of the present work is to compare induction of CYP1A (determined at the catalytic level as 7-ethoxyresorufin-O-deethylase, EROD) in rainbow trout (Oncorhynchus mykiss) hepatocytes by the prototypic AhR ligand, beta-naphthoflavone (betaNF), and by the imidazole derivative, 1-phenylimidazole (PIM). PIM was able to induce EROD activity although its potency was clearly lower than that of betaNF. In order to assess the relative importance of classical AhR ligand binding and alternative signaling pathways in CYP1A induction by PIM, co-exposure experiments with the partial AhR antagonist alpha-naphthoflavone (alphaNF) or with inhibitors of protein kinase C (staurosporine) and tyrosine kinases (genistein, herbimicine) were performed. alphaNF and herbimicin provoked a decrease of EROD induction both by betaNF and PIM, whereas staurosporine and genistein remained without effect. The overall similarities in the response of betaNF and PIM to the various inhibitors suggest that both compounds, in apparent contrast to the behaviour of some other imidazole derivatives, induce CYP1A following similar mechanisms.
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Affiliation(s)
- A Jos
- Area of Toxicology, Faculty of Pharmacy, University of Seville, Professor García González 2, E-41012 Seville, Spain
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Willets JM, Nelson CP, Nahorski SR, Challiss RAJ. The regulation of M1 muscarinic acetylcholine receptor desensitization by synaptic activity in cultured hippocampal neurons. J Neurochem 2007; 103:2268-80. [PMID: 17908240 PMCID: PMC2658029 DOI: 10.1111/j.1471-4159.2007.04931.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
To better understand metabotropic/ionotropic integration in neurons we have examined the regulation of M1 muscarinic acetylcholine (mACh) receptor signalling in mature (> 14 days in vitro), synaptically-active hippocampal neurons in culture. Using a protocol where neurons are exposed to an EC(50) concentration of the muscarinic agonist methacholine (MCh) prior to (R1), and following (R2) a desensitizing pulse of a high concentration of this agonist, we have found that the reduction in M(1) mACh receptor responsiveness is decreased in quiescent (+tetrodotoxin) neurons and increased when synaptic activity is enhanced by blocking GABA(A) receptors with picrotoxin. The picrotoxin-mediated effect on M1 mACh receptor responsiveness was completely prevented by alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor blockade. Inhibition of endogenous G protein-coupled receptor kinase 2 by transfection with the non-G(q/11)alpha-binding, catalytically-inactive (D110A,K220R)G protein-coupled receptor kinase 2 mutant, decreased the extent of M1 mACh receptor desensitization under all conditions. Pharmacological inhibition of protein kinase C (PKC) activity, or chronic phorbol ester-induced PKC down-regulation had no effect on agonist-mediated receptor desensitization in quiescent or spontaneously synaptically active neurons, but significantly decreased the extent of receptor desensitization in picrotoxin-treated neurons. MCh stimulated the translocation of diacylglycerol- sensitive eGFP-PKCepsilon, but not Ca2+/diacylglycerol-sensitive eGFP-PKCbetaII in both the absence, and presence of tetrodotoxin. Under these conditions, MCh-stimulated eGFP-myristoylated, alanine-rich C kinase substrate translocation was dependent on PKC activity, but not Ca2+/calmodulin. In contrast, picrotoxin-driven translocation of myristoylated, alanine-rich C kinase substrate was accompanied by translocation of PKCbetaII, but not PKCepsilon, and was dependent on PKC and Ca2+/calmodulin. Taken together these data suggest that the level of synaptic activity may determine the different kinases recruited to regulate M1 mACh receptor desensitization in neurons.
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Affiliation(s)
- Jonathon M Willets
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, UK
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Goestemeyer AK, Marks J, Srai SK, Debnam ES, Unwin RJ. GLUT2 protein at the rat proximal tubule brush border membrane correlates with protein kinase C (PKC)-betal and plasma glucose concentration. Diabetologia 2007; 50:2209-17. [PMID: 17694297 DOI: 10.1007/s00125-007-0778-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2007] [Accepted: 06/21/2007] [Indexed: 12/28/2022]
Abstract
AIMS/HYPOTHESIS GLUT2 is the main renal glucose transporter upregulated by hyperglycaemia, when it becomes detectable at the brush border membrane (BBM). Since glucose-induced protein kinase C (PKC) activation in the kidney is linked to diabetic nephropathy, we investigated the effect of glycaemic status on the protein levels of PKC isoforms alpha, betaI, betaII, delta and epsilon in the proximal tubule, as well as the relationship between them and changes in GLUT2 production at the BBM. METHODS Plasma glucose concentrations were modulated in rats by treatment with nicotinamide 15 min prior to induction of diabetes with streptozotocin. Levels of GLUT2 protein and PKC isoforms in BBM were measured by western blotting. Additionally, the role of calcium signalling and PKC activation on facilitative glucose transport was examined by measuring glucose uptake in BBM vesicles prepared from proximal tubules that had been incubated either with thapsigargin, which increases cytosolic calcium, or with the PKC activator phorbol 12-myristate,13-acetate (PMA). RESULTS Thapsigargin and PMA enhanced GLUT-mediated glucose uptake, but had no effect on sodium-dependent glucose transport. Diabetes significantly increased the protein levels of GLUT2 and PKC-betaI at the BBM. Levels of GLUT2 and PKC-betaI correlated positively with plasma glucose concentration. Diabetes had no effect on BBM levels of alpha, betaII, delta or epsilon isoforms of PKC. CONCLUSIONS/INTERPRETATION Enhanced GLUT2-mediated glucose transport across the proximal tubule BBM during diabetic hyperglycaemia is closely associated with increased PKC-betaI. Thus, altered levels of GLUT2 and PKC-betaI proteins in the BBM may be important factors in the pathogenic processes underlying diabetic renal injury.
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Affiliation(s)
- A K Goestemeyer
- Department of Physiology, Royal Free and University College Medical School, Hampstead Campus, Rowland Hill Street, London, NW3 2PF, UK
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Morishita R, Ueda H, Ito H, Takasaki J, Nagata KI, Asano T. Involvement of Gq/11 in both integrin signal-dependent and -independent pathways regulating endothelin-induced neural progenitor proliferation. Neurosci Res 2007; 59:205-14. [PMID: 17707940 DOI: 10.1016/j.neures.2007.06.1478] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 06/04/2007] [Accepted: 06/27/2007] [Indexed: 12/28/2022]
Abstract
We have previously shown that endothelin-B receptor stimulation increases neural progenitor proliferation, partly in G(i) and extracellular matrix molecule-dependent manner. In the present study, we investigated whether G(q/11) is also involved in this response and how G(i) and G(q/11) might regulate the extracellular signal-regulated kinase (ERK) pathway and integrin signaling. Endothelin-induced ERK phosphorylation was independent of integrin ligands, and an inhibitor of G(q/11), YM-254890, as well as pertussis toxin, partially inhibited endothelin-stimulated phosphorylation of Raf-1 and ERK. Endothelin-stimulated protein kinase C (PKC) was partially inhibited by both YM-254890 and pertussis toxin, while only pertussis toxin attenuated endothelin-induced Ras activation. In contrast, endothelin increased tyrosine phosphorylation of focal adhesion kinase (FAK) and paxillin in an integrin ligand-dependent manner. Both YM-254890 and pertussis toxin partially inhibited endothelin-stimulated phosphorylation of these proteins. A PKC inhibitor and down-regulation of PKC prevented endothelin-induced phosphorylation of paxillin and ERK. In addition, endothelin-induced proliferation and DNA synthesis were partially inhibited by YM-254890 and pertussis toxin. Taken together, the results indicate that endothelin activates PKC via G(q/11) and G(i), and consequently stimulates the ERK cascade in cooperation with Ras signaling stimulated by G(i). PKC appears to increase tyrosine phosphorylation of paxillin to enhance integrin signaling, which further increases DNA synthesis and proliferation.
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Affiliation(s)
- Rika Morishita
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kamiya-cho, Kasugai, Aichi 480-0392, Japan
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Asaoka Y, Yoshida K, Oka M, Shinomura T, Mishima H, Matsushima S, Nishizuka Y. The signal-induced phospholipid degradation cascade and protein kinase C activation. Ciba Found Symp 2007; 164:50-9; discussion 59-65. [PMID: 1395935 DOI: 10.1002/9780470514207.ch5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Acting in synergy with diacylglycerol, unsaturated free fatty acids such as arachidonic, oleic, linoleic, linolenic and docosahexaenoic acids dramatically activate some members of the protein kinase C family at the basal level of Ca2+ concentration. It is plausible that phospholipase C and phospholipase A2, and possibly phospholipase D as well, are involved in the activation of protein kinase C. Presumably, this enzyme activation is integrated into the signal-induced membrane phospholipid degradation cascade, prolonging the activation of protein kinase C. The sustained activity of this enzyme appears to be of importance for long-term cellular responses such as development of neuronal plasticity and gene activation.
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Affiliation(s)
- Y Asaoka
- Biosignal Research Center, Kobe University, Japan
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Rojas A, Cui N, Su J, Yang L, Muhumuza JP, Jiang C. Protein kinase C dependent inhibition of the heteromeric Kir4.1-Kir5.1 channel. Biochim Biophys Acta 2007; 1768:2030-42. [PMID: 17585871 PMCID: PMC2228331 DOI: 10.1016/j.bbamem.2007.04.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2006] [Revised: 03/22/2007] [Accepted: 04/04/2007] [Indexed: 11/13/2022]
Abstract
Heteromultimerization of Kir4.1 and Kir5.1 leads to a channel with distinct functional properties. The heteromeric Kir4.1-Kir5.1 channel is expressed in the eye, kidney and brainstem and has CO(2)/pH sensitivity in the physiological range, suggesting a candidate molecule for the regulation of K(+) homeostasis and central CO(2) chemoreception. It is known that K(+) transport in renal epithelium and brainstem CO(2) chemosensitivity are subject to modulation by hormones and neurotransmitters that activate distinct intracellular signaling pathways. If the Kir4.1-Kir5.1 channel is involved in pH-dependent regulation of cellular functions, it may also be regulated by some of the intracellular signaling systems. Therefore, we undertook studies to determine whether PKC modulates the heteromeric Kir4.1-Kir5.1 channel. The channel expressed using a Kir4.1-Kir5.1 tandem dimer construct was inhibited by the PKC activator PMA in a dose-dependent manner. The channel inhibition was produced via reduction of the P(open). The effect of PMA was abolished by specific PKC inhibitors. In contrast, exposure of oocytes to forskolin (a PKA activator) had no significant effect on Kir4.1-Kir5.1 currents. The channel inhibition appeared to be independent of PIP(2) depletion and PKC-dependent internalization. Several consensus sequences of potential PKC phosphorylation sites were identified in the Kir4.1 and Kir5.1 subunits by sequence scan. Although the C-terminal peptides of both Kir4.1 and Kir5.1 were phosphorylated in vitro, site-directed mutagenesis of individual residues failed to reveal the PKC phosphorylation sites suggesting that the channel may have multiple phosphorylation sites. Taken together, these results suggest that the Kir4.1-Kir5.1 but not the homomeric Kir4.1 channel is strongly inhibited by PKC activation.
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Affiliation(s)
- Asheebo Rojas
- Department of Biology, Georgia State University, 24 Peachtree Center Avenue Atlanta, GA 30302-4010
| | - Ningren Cui
- Department of Biology, Georgia State University, 24 Peachtree Center Avenue Atlanta, GA 30302-4010
| | - Junda Su
- Department of Biology, Georgia State University, 24 Peachtree Center Avenue Atlanta, GA 30302-4010
| | - Liang Yang
- Department of Biology, Georgia State University, 24 Peachtree Center Avenue Atlanta, GA 30302-4010
| | - Jean-Pierre Muhumuza
- Department of Biology, Georgia State University, 24 Peachtree Center Avenue Atlanta, GA 30302-4010
| | - Chun Jiang
- Department of Biology, Georgia State University, 24 Peachtree Center Avenue Atlanta, GA 30302-4010
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Swiatek-De Lange M, Stampfl A, Hauck SM, Zischka H, Gloeckner CJ, Deeg CA, Ueffing M. Membrane-initiated effects of progesterone on calcium dependent signaling and activation of VEGF gene expression in retinal glial cells. Glia 2007; 55:1061-73. [PMID: 17551930 DOI: 10.1002/glia.20523] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Neurosteroids, such as progesterone, influence central nervous system development and function by regulating a broad spectrum of physiological processes. Here, we investigated membrane-initiated actions of progesterone in the retina and identified the membrane-associated progesterone receptor component 1 (PGRMC1). We found PGRMC1 expressed mainly in retinal Muller glia (RMG) and retinal pigment epithelium, and localized uniquely to microsomal and plasma membrane fractions. In RMG, membrane-impermeable progesterone conjugate induced calcium influx and subsequent phosphatidylinositol 3-kinase-mediated phosphorylation of PKC and ERK-1/2. Induction by progesterone also led to PKC-dependent activation of VEGF gene expression and protein synthesis, suggesting a contribution of membrane-initiated hormone effects to VEGF induced neovascularization within retina.
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Affiliation(s)
- Magdalena Swiatek-De Lange
- Institute of Human Genetics, GSF National-Research Center for Environment and Health, Neuherberg, Germany
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Zha DJ, Wang ZM, Lin Y, Liu T, Qiao L, Lu LJ, Li YQ, Qiu JH. Effects of noradrenaline on the GABA response in rat isolated spiral ganglion neurons in culture. J Neurochem 2007; 103:57-66. [PMID: 17645455 DOI: 10.1111/j.1471-4159.2007.04776.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the present study, the modulatory effects of noradrenaline (NA) on the GABA response were investigated in the isolated cultured spiral ganglion neurons of rat by using nystatin perforated patch recording configuration under voltage-clamp conditions. NA reversibly depressed GABA response in a concentration-dependent manner and neither changed the reversal potential of the GABA response nor affected the apparent affinity of GABA to its receptor. alpha2-adrenoceptor agonist and antagonist, clonidine and yohimbine mimicked and blocked the NA action on the GABA response, respectively. N-[2(methylamino)ethyl]-5-isoquinoline sulfonamide dihydrochloride (H-89), a protein kinase A inhibitor, mimicked the effect of NA on the GABA response. NA failed to affect the GABA response in the presence of both cAMP and protein kinase A modulator. However, NA still depressed the GABA response even in the presence of both phorbol-12-myristate-13-acetate, a protein kinase C activator and chelerythrine, a protein kinase C inhibitor. These results suggest that the NA suppression of the GABA response is mediated by alpha2-adrenoceptor which reduces intracellular cAMP formation through the inhibition of adenylyl cyclase. Therefore, NA input to the spiral ganglion neurons may modulate the auditory transmission by affecting the GABA response.
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Affiliation(s)
- Ding-Jun Zha
- Department of Otorhinolaryngology, Affiliated Xijing Hospital, The Fourth Military Medical University, Xi'an, China
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Morimoto M, Tanabe F, Kasai H, Ito M. Effect of a thiol proteinase inhibitor, E-64-d, on susceptibility to infection with Staphylococcus aureus in Chediak–Higashi syndrome (beige) mice. Int Immunopharmacol 2007; 7:973-80. [PMID: 17499200 DOI: 10.1016/j.intimp.2007.03.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Revised: 03/16/2007] [Accepted: 03/16/2007] [Indexed: 10/23/2022]
Abstract
We previously reported that abnormally down-regulated protein kinase C (PKC) activity is responsible for the impaired cellular function of natural killer cells and polymorphonuclear cells (PMNs), and the giant granule formation in fibroblasts in the beige mouse, an animal model of Chediak-Higashi syndrome. Here, we examine the effect of oral or intraperitoneal administration of E-64-d, which protects PKC from calpain-mediated proteolysis, on the impaired cellular function in PMNs from beige mice. We found that oral administration of E-64-d (12.5 mg/kg body weight per day) for three consecutive days, significantly improved the abnormally increased concanavalin A (Con A) cap formation and the decreased lysosomal enzyme activity in beige PMNs. In addition, E-64-d significantly improved the delayed bactericidal activity against Staphylococcus aureus. In contrast, E-64-d at the same dose did not affect these cellular functions in PMNs from C57BL/6J mice. We confirmed that the abnormal down-regulation of PKC after Con A stimulation was eliminated in PMNs from E-64-d-treated beige PMNs. We then examined whether the administration of E-64-d to beige mice improved the susceptibility to experimental infection with S. aureus (2x10(8)/mouse). Both intraperitoneal and oral administration of E-64-d to beige mice resulted in a significant increase in survival, whereas E-64-d at the same dose did not alter the survival rate in normal mice. These results suggest that the administration of E-64-d may be effective against severe bacterial infection in Chediak-Higashi syndrome.
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Affiliation(s)
- Michiko Morimoto
- Department of Microbiology, Faculty of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi 409-3898, Japan
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Santos ALSD, Soares RMDA. Effect of sphingosine and phorbol-12-myristate-13-acetate on the growth and dimethylsulfoxide-induced differentiation in the insect trypanosomatid Herpetomonas samuelpessoai. Mem Inst Oswaldo Cruz 2007; 102:601-4. [PMID: 17710305 DOI: 10.1590/s0074-02762007005000059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2007] [Accepted: 04/26/2007] [Indexed: 11/22/2022] Open
Abstract
We investigated the effect of two modulators of protein kinase C, sphingosine and phorbol-12-myristate-13-acetate (PMA), on the growth and dimethylsulfoxide (DMSO)-induced differentiation in Herpetomonas samuelpessoai. Sphingosine did not stimulate the transformation of undifferentiated-promastigotes in differentiated-paramastigotes. PMA alone or in association with DMSO increased the number of paramastigotes in comparison to control cells. DMSO inhibited the parasite growth (35%) and several unusual morphological features resembling aberrant cell division were observed. Sphingosine did not significantly reduce the growth in contrast to PMA. Collectively, our results demonstrated that the reduction of the proliferation translates in an increase of the differentiation rate in the insect trypanosomatid H. samuelpessoai.
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Affiliation(s)
- André Luis Souza dos Santos
- Laboratório de Estudos Integrados em Bioquímica Microbiana, Universidade Federal do Rio de Janeiro, RJ, Fiocruz, Rio de Janeiro, RJ, Brasil.
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Abstract
Thymosin alpha1 (Talpha1) is a 28 amino acid biologically active protein cleaved from positions 2-29 of a precursor protein, prothymosin alpha. Since its discovery, Talpha1 has been administered to animals and humans in a wide variety of settings and its pharmacologic effects are to enhance cellular immunity. Talpha1 administration is highly effective in settings where irradiation, chemotherapy, tumor burden, or immune senescence have caused a reduction of T cell number and/or function. Recent in vitro studies, including the one reported here, suggest that Talpha1 may act via pathways commonly used by various cytokines. This raises the possibility that Talpha1 and cytokines may have synergistic activity through potentiation of cytokine activity by Talpha1. Improved control of tumor growth when tumor-bearing mice were treated with Talpha1 and high doses of IL-2 has been previously reported. We extended those studies with the Lewis lung carcinoma mouse model using IRX-2, a natural well-defined biologic containing multiple cytokines, in combination with Talpha1 (IRX-3). Although IRX-2 was effective alone (using doses that contain significantly less IL-2 than in most typical studies), adding Talpha1 led to significant improvement in survival of the tumor-bearing mice. Based on these observations, the immunopharmacology of Talpha1 predicts an important clinical role for Talpha1 in the restoration of cellular immune activity when used in combination with cytokines. Patients who experience immune suppression due to the presence of tumor, irradiation, and/or chemotherapy or aging of the host would most benefit from this treatment combination.
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Affiliation(s)
- Paul H Naylor
- IRX Therapeutics Inc., 1 BioScience Park Drive, Farmingdale, NY 11735, USA.
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Egea J, Rosa AO, Cuadrado A, García AG, López MG. Nicotinic receptor activation by epibatidine induces heme oxygenase-1 and protects chromaffin cells against oxidative stress. J Neurochem 2007; 102:1842-1852. [PMID: 17540012 DOI: 10.1111/j.1471-4159.2007.04665.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Activation of neuronal nicotinic acetylcholine receptors (nAChR) provides neuroprotection against different toxic stimuli that often lead to overproduction of reactive oxygen species (ROS) and cell death. ROS production has been related with disease progression in several neurodegenerative pathologies such as Alzheimer's or Parkinson's diseases. In this context, we investigated here if the exposure of bovine chromaffin cells to the potent nAChR agonist epibatidine protected against rotenone (30 micromol/L) plus oligomycin (10 micromol/L) (rot/oligo) toxicity, an in vitro model of mitochondrial ROS production. Epibatidine induced a concentration- and time-dependent protection, which was maximal at 3 mumol/L after 24 h. Pre-incubation with dantrolene (100 micromol/L) (a blocker of the ryanodine receptor channel), chelerythrine (1 micromol/L) (a protein kinase C inhibitor), or PD98059 (50 micromol/L) (a MEK inhibitor), aborted epibatidine-elicited cytoprotection. Mitochondrial depolarization, ROS, and caspase 3 active produced by rot/oligo were also prevented by epibatidine. Epibatidine doubled the amount of heme oxygenase-1 (HO-1), a critical cell defence enzyme against oxidative stress. Furthermore, the HO-1 inhibitor Sn(IV) protoporphyrin IX dichloride reversed the epibatidine protecting effects and HO-1 inducer Co (III) protoporphyrin IX dichloride exhibited neuroprotective effects by itself. The results of this study point to HO-1 as the cytoprotective target of nAChR activation through the following pathway: endoplasmic reticulum Ca(2+)-induced Ca(2+)-release activates the protein kinase C/extracellular regulated kinase/HO-1 axis to mitigate mitochondrial depolarization and ROS production. This study provides a mechanistic insight on how nAChR activation translates into an antioxidant and antiapoptotic signal through up-regulation of HO-1.
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Affiliation(s)
- Javier Egea
- Intituto Teofilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, SpainDepartamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, SpainServicio de Farmacología Clínica and Instituto Universitario de Investigación Gerontológica y metabólica, Hospital Universitario de la Princesa, Madrid, Spain
| | - Angelo O Rosa
- Intituto Teofilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, SpainDepartamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, SpainServicio de Farmacología Clínica and Instituto Universitario de Investigación Gerontológica y metabólica, Hospital Universitario de la Princesa, Madrid, Spain
| | - Antonio Cuadrado
- Intituto Teofilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, SpainDepartamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, SpainServicio de Farmacología Clínica and Instituto Universitario de Investigación Gerontológica y metabólica, Hospital Universitario de la Princesa, Madrid, Spain
| | - Antonio G García
- Intituto Teofilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, SpainDepartamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, SpainServicio de Farmacología Clínica and Instituto Universitario de Investigación Gerontológica y metabólica, Hospital Universitario de la Princesa, Madrid, Spain
| | - Manuela G López
- Intituto Teofilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, SpainDepartamento de Bioquímica, Universidad Autónoma de Madrid, Madrid, SpainServicio de Farmacología Clínica and Instituto Universitario de Investigación Gerontológica y metabólica, Hospital Universitario de la Princesa, Madrid, Spain
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Abstract
The paraventricular nucleus (PVN) contains spinally-projecting neurons implicated in fine-tuning the cardiovascular system. In vivo activity of "presympathetic" parvocellular neurons is suppressed by tonic inhibition from GABA-ergic inputs, inhibition of which increases sympathetic pressor activity and heart rate. Targeting of this specific neuronal population could potentially limit elevations of heart rate and blood pressure associated with disease. Here we show, for the first time, that "presympathetic" PVN neurons are disinhibited by the neuropeptide substance P (SP) acting via tachykinin NK1 receptor inhibition of GABA(A) currents. Application of SP to the paraventricular nucleus of rats increases heart rate and blood pressure. In in vitro brain slice experiments, in the presence of GABA, 1 micromol/L SP increased action current frequency by a factor of 2.7+/-0.6 (n=5, P< or =0.05, ANOVA). Furthermore, 1 micromol/L SP inhibited GABA(A) currents by 70+/-8% (n=8, P< or =0.005 paired t test). These effects were abolished by NK1 antagonists, but not NK2 and NK3 antagonists. GABA(A) inhibition was not reproduced by NK2 or NK3 agonists. The inhibition of parvocellular GABA(A) currents by SP was also abolished by a protein kinase C (PKC) inhibitor peptide and mimicked by application of phorbol-12-myristate-13-acetate (PMA), implicating a PKC-dependent mechanism. Single-channel analysis indicates that SP acts through reduction of channel mean open-time (cmot): GABA(A) cmot being reduced by approximately 60% by SP (P< or =0.05 ANOVA, Bonferroni). These data suggest that tachykinins mediate their pressor activity by increasing the excitability of spinally-projecting neurons and identifies NK1 receptors as potential targets for therapeutic modulation of the cardiovascular system.
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Affiliation(s)
- Matthew D Womack
- Veterinary Sciences Faculty, Brownlow Hill, University of Liverpool, UK
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Einicker-Lamas M, Nascimento MTC, Masuda CA, Oliveira MM, Caruso-Neves C. Trypanosoma cruzi epimastigotes: regulation of myo-inositol transport by effectors of protein kinases A and C. Exp Parasitol 2007; 117:171-7. [PMID: 17586497 DOI: 10.1016/j.exppara.2007.04.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 04/11/2007] [Accepted: 04/23/2007] [Indexed: 01/10/2023]
Abstract
Inositol is the precursor for most Trypanosoma cruzi surface molecules, including phosphoinositides, glycosylinositolphospholipids and glycosylphosphatidylinositol anchors. As the parasite is an inositol auxotroph, the inositol transport system might be a potential target for new trypanocide drugs, as some of its properties are different from its mammalian counterpart. Here, we investigated the modulation exerted by effectors of PKA and PKC on this transport system to comply with the parasite physiology. Pre-incubation of the cells with either dibutyryl-cyclic AMP (25 microM) or forskolin (30 microM) decreased the myo-inositol uptake by half, this effect being reversed by KT5720 (PKA inhibitor). Conversely, pre-incubation of the cells with PMA (2.8 microg/ml) or serum (5%) had a approximately 50% stimulation in myo-inositol uptake, being this effect reversed by staurosporine (0.5 microM) or sphingosine (10 microM). These results allow us to conclude that the myo-inositol transport system in T. cruzi epimastigotes is inhibited by PKA and stimulated by PKC effectors.
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Affiliation(s)
- Marcelo Einicker-Lamas
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-590 Rio de Janeiro, Brazil
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