Involvement of obestatin, cyclin-dependent kinase and protein kinase C in control of feline ovarian cell viability and hormones release

2021 ◽  
Vol 21 (4) ◽  
pp. 100560
Author(s):  
Barbora Loncová ◽  
Zuzana Fabová ◽  
Alexander V. Sirotkin
2009 ◽  
Vol 111 (3) ◽  
pp. 566-573 ◽  
Author(s):  
Jie-Ae Kim ◽  
Liaoliao Li ◽  
Zhiyi Zuo

Background Isoflurane pretreatment can induce protection against lipopolysaccharide and interferon gamma (IFNgamma)-induced injury and activation of mouse microglial cells. This study's goal was to determine whether delayed isoflurane treatment is protective. Methods Mouse microglial cells were exposed to various concentrations of isoflurane for 1 h immediately after the initiation of lipopolysaccharide (10 or 1000 ng/ml) and IFNgamma (10 U/ml) stimulation or to 2% isoflurane for 1 h at various times after initiation of the stimulation. Nitrite production, lactate dehydrogenase release, and cell viability measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay were assessed after stimulation with lipopolysaccharide and IFNgamma for 24 h. Inducible nitric oxide synthase (iNOS) protein expression was quantified by Western blotting. The iNOS expression in mouse brain was also studied. Results Isoflurane applied 0 and 2 h after the initiation of lipopolysaccharide and IFNgamma stimulation improved cell viability. Isoflurane at 2%, but not at 1 or 3%, reduced the lipopolysaccharide and IFNgamma-induced nitrite production and decreased cell viability. Aminoguanidine, an iNOS inhibitor, also attenuated this decreased cell viability. Chelerythrine and bisindolylmalemide IX, protein kinase C inhibitors, abolished isoflurane effects on cell viability and iNOS expression after lipopolysaccharide and IFNgamma application. Isoflurane also decreased lipopolysaccharide-induced iNOS expression in mouse brain. Late isoflurane application to microglial cells reduced lipopolysaccharide and IFNgamma-induced lactate dehydrogenase release that was not inhibited by aminoguanidine. Conclusions These results suggest that delayed isoflurane treatment can reduce lipopolysaccharide and IFNgamma-induced activation and injury of microglial cells. These effects may be mediated by protein kinase C.


1999 ◽  
Vol 340 (3) ◽  
pp. 775-782 ◽  
Author(s):  
Stéphane MANENTI ◽  
Emiko YAMAUCHI ◽  
Odile SOROKINE ◽  
Martine KNIBIEHLER ◽  
Alain VAN DORSSELAER ◽  
...  

The myristoylated alanine-rich C-kinase substrate (MARCKS) purified from brain was recently characterized as a proline-directed kinase(s) substrate in vivo [Taniguchi, Manenti, Suzuki and Titani (1994) J. Biol. Chem. 269, 18299-18302]. Here we have investigated the phosphorylation of MARCKS by various cyclin-dependent kinases (Cdks) in vitro. We established that Cdk2, Cdk4 and, to a smaller extent, Cdk1 that have been immunoprecipitated from cellular extracts phosphorylate MARCKS. Comparison of MARCKS phosphorylation by protein kinase C (PKC) and by the purified cyclin E-Cdk2 complex suggested that two residues were phosphorylated by Cdk2 under these conditions. To identify these sites, Cdk2-phosphorylated MARCKS was digested with lysyl endoprotease and analysed by electrospray MS. Comparison with the digests obtained from the unphosphorylated protein demonstrated that two peptides, Gly12-Lys30 and Ala138-Lys152, were phosphorylated by cyclin E-Cdk2. The identity of these peptides was confirmed by automatic Edman degradation. On the basis of the consensus phosphorylation sequence described for Cdk2, and on MS/MS analysis of the Ala138-Lys152 peptide, we concluded that Ser27, one of the phosphorylation sites identified in vivo, and Thr150 were the Cdk2 targets in vitro. None of the other sites described in vivo were phosphorylated in these conditions. Interestingly, a preliminary phosphorylation of MARCKS by PKC improved the initial rate of phosphorylation by Cdk2 without modifying the number of sites concerned. In contrast, phosphorylation of MARCKS by Cdk2 did not significantly affect further phosphorylation by PKC.


2005 ◽  
Vol 23 (9) ◽  
pp. 1875-1884 ◽  
Author(s):  
Jeremy Kortmansky ◽  
Manish A. Shah ◽  
Andreas Kaubisch ◽  
Amanda Weyerbacher ◽  
Sandy Yi ◽  
...  

Purpose Preclinical studies indicate that the cyclin-dependent kinase and protein kinase C inhibitor 7-hydroxystaurosporine (UCN-01) potentiates the cytotoxic effects of fluorouracil (FU). We designed a phase I clinical trial of FU in combination with UCN-01. Patients and Methods FU was administered as a weekly 24-hour infusion. Doses were escalated in successive cohorts according to a modified Fibonacci design. UCN-01 was administered once every 4 weeks, immediately after disconnection from FU, at a dose of 135 mg/m2 over 72 hours in cycle 1 and 67.5 mg/m2 over 36 hours in subsequent cycles. FU and UCN-01 pharmacokinetics were obtained on all patients, and thymidylate synthetase (TS) activity was measured in peripheral-blood mononuclear cells by reverse-transcriptase polymerase chain reaction. Results We escalated the weekly FU dose to 2,600 mg/m2 in combination with once a month infusions of UCN-01. Dose-limiting toxicity included arrhythmia and syncope. Other toxicities included hyperglycemia, headache, and nausea and vomiting. The mean maximal plasma concentration of UCN-01 was 33.5 μmol/L. There was significant interpatient variability, which correlated with plasma concentrations of alpha-1 acid glycoprotein. FU was rapidly cleared and the dose had no effect on the area under the curve of UCN-01. Changes in TS expression were detectable in peripheral-blood mononuclear cells after administration of UCN-01 but did not correlate with toxicity or activity. We observed no objective response, although seven patients had stable disease, six of whom had received prior fluoropyrimidines. Conclusion The combination of weekly infusions of FU and monthly UCN-01 can be administered safely and warrants further study in phase II trials. The recommended phase II dose of FU in combination with monthly UCN-01 is 2,600 mg/m2.


2011 ◽  
Vol 18 (4) ◽  
pp. 439-450 ◽  
Author(s):  
Daniela Molè ◽  
Teresa Gagliano ◽  
Erica Gentilin ◽  
Federico Tagliati ◽  
Claudio Pasquali ◽  
...  

Dysregulation of the protein kinase C (PKC) signaling pathway has been implicated in tumor progression. In this study, we investigate the effects of a PKC inhibitor, Enzastaurin, in human pancreatic neuroendocrine neoplasms (PNN) primary cultures and in the human pancreatic endocrine cancer cell line, BON1. To this aim six human PNN dispersed in primary cultures and BON1 cells were treated without or with 1–10 μM Enzastaurin and/or 100 nM IGF1 in the presence or absence of serum. Cell viability and apoptosis were evaluated after 48–72 h; Chromogranin A (CgA) and/or insulin secretion was assessed after 6 h of incubation. PKC expression was investigated by immunofluorescence and western blot. We found that Enzastaurin significantly reduced human PNN primary culture cell viability, as well as CgA and insulin secretion. Moreover, in the BON1 cell line Enzastaurin inhibited cell proliferation at 5 and 10 μM by inducing caspase-mediated apoptosis, and reduced phosphorylation of glycogen synthetase kinase 3β (GSK3β) and of Akt, both downstream targets of PKC pathway and pharmacodynamic markers for Enzastaurin. In addition, Enzastaurin blocked the stimulatory effect of IGF1 on cell proliferation, and reduced CgA expression and secretion in BON1 cells. Two different PKC isoforms are expressed at different levels and have partially different subcellular localization in BON1 cells. In conclusion, Enzastaurin reduces cell proliferation by inducing apoptosis, with a mechanism likely involving GSK3β signaling, and inhibits secretory activity in PNN in vitro models, suggesting that Enzastaurin might represent a possible medical treatment of human PNN.


1999 ◽  
Vol 340 (3) ◽  
pp. 775 ◽  
Author(s):  
Stéphane MANENTI ◽  
Emiko YAMAUCHI ◽  
Odile SOROKINE ◽  
Martine KNIBIEHLER ◽  
Alain VAN DORSSELAER ◽  
...  

2008 ◽  
Vol 108 (4) ◽  
pp. 643-650 ◽  
Author(s):  
Xuebing Xu ◽  
Jifeng Feng ◽  
Zhiyi Zuo

Background Isoflurane exposure before an insult can reduce the insult-induced injury in various organs. This phenomenon is called isoflurane preconditioning. The authors hypothesize that isoflurane can precondition macrophages, cells that travel to all tissues and are important in the host defense and inflammation responses. Methods Rat NR8383 macrophages were pretreated with or without 1-3% isoflurane for 1 h at 30 min before they were incubated with or without 100 ng/ml lipopolysaccharide plus 50 U/ml interferon gamma for 24 h. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Flow cytometry was performed after cells were stained with annexin V and propidium iodide. Inducible nitric oxide synthase protein expression in macrophages was quantified by Western blotting. Results Lipopolysaccharide plus interferon gamma decreased cell viability by approximately 50%. This decrease was dose-dependently inhibited by aminoguanidine, an inducible nitric oxide synthase inhibitor. Lipopolysaccharide plus interferon gamma caused inducible nitric oxide synthase expression. This expression was inhibited by pretreatment with 2% but not 1% or 3% isoflurane. Isoflurane at 2% inhibited lipopolysaccharide plus interferon gamma-induced accumulation of nitrite, an oxidation product of nitric oxide. Pretreatment with 2% but not 1% or 3% isoflurane improved cell viability. Lipopolysaccharide plus interferon gamma increased the number of propidium iodide-positive staining cells. This increase was attenuated by 2% isoflurane pretreatment. The protective effect of 2% isoflurane was abolished by chelerythrine, calphostin C, or bisindolylmaleimide IX, protein kinase C inhibitors. Conclusions Lipopolysaccharide plus interferon gamma causes an inducible nitric oxide synthase-dependent macrophage injury. Isoflurane induces preconditioning effects that may be mediated by protein kinase C in macrophages.


2019 ◽  
Vol 20 (3) ◽  
pp. 316-339 ◽  
Author(s):  
Jahangir Alam ◽  
Lalit Sharma

Alzheimer’s, a degenerative cause of the brain cells, is called as a progressive neurodegenerative disease and appears to have a heterogeneous etiology with main emphasis on amyloid-cascade and hyperphosphorylated tau-cascade hypotheses, that are directly linked with macromolecules called enzymes such as β- & γ-secretases, colinesterases, transglutaminases, and glycogen synthase kinase (GSK-3), cyclin-dependent kinase (cdk-5), microtubule affinity-regulating kinase (MARK). The catalytic activity of the above enzymes is the result of cognitive deficits, memory impairment and synaptic dysfunction and loss, and ultimately neuronal death. However, some other enzymes also lead to these dysfunctional events when reduced to their normal activities and levels in the brain, such as α- secretase, protein kinase C, phosphatases etc; metabolized to neurotransmitters, enzymes like monoamine oxidase (MAO), catechol-O-methyltransferase (COMT) etc. or these abnormalities can occur when enzymes act by other mechanisms such as phosphodiesterase reduces brain nucleotides (cGMP and cAMP) levels, phospholipase A2: PLA2 is associated with reactive oxygen species (ROS) production etc. On therapeutic fronts, several significant clinical trials are underway by targeting different enzymes for development of new therapeutics to treat Alzheimer’s, such as inhibitors for β-secretase, GSK-3, MAO, phosphodiesterase, PLA2, cholinesterases etc, modulators of α- & γ-secretase activities and activators for protein kinase C, sirtuins etc. The last decades have perceived an increasing focus on findings and search for new putative and novel enzymatic targets for Alzheimer’s. Here, we review the functions, pathological roles, and worth of almost all the Alzheimer’s associated enzymes that address to therapeutic strategies and preventive approaches for treatment of Alzheimer’s.


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