The differential effects of neuroleptic drugs and PACAP on the expression of BDNF mRNA and protein in a human glioblastoma cell line

It has been suggested that, in addition to modulation of monoaminergic neurotransmission, antipsychotic drugs can also affect expression of neurotrophic factors in the brain. The present study was aimed to examine the effects of the first generation neuroleptic drug (FGA; haloperidol) and second generation neuroleptic drugs (SGAs; olanzapine and amisulpride) on expression and level of brain-derived neurotrophic factor (BDNF) in astrocyte-like T98G glioblastoma cell line. Effects of these drugs were compared to the action of PACAP38, a neuropeptide with well known BDNF-mediated neuroprotective effects. The tested neuroleptics differentially regulated the mRNA expression and protein level of BDNF depending on the concentration and incubation time. Using rtPCR technique, we demonstrate that, from the three tested neuroleptics, both haloperidol as well as olanzapine at 5 μM concentration (but not at 20 μM) increased BDNF mRNA expression with a similar efficacy after a 72 h incubation. In order to confirm the observed changes in the mRNA expression of BDNF, a protein expression assay was performed. The exposure of cells only to 5 μM olanzapine for 72 h increased BDNF concentration in the culture medium by 29%. Additionally, PACAP significantly up-regulated BDNF mRNA expression in T98G cells and the obtained results correlated positively with the increased production of BDNF protein, by 22% above control. The results of the paper show that olanzapine, similarly to exogenous PACAP38, increased BDNF mRNA expression and protein release, which can contribute to its neuroprotective mechanism of action in the cells of nonneuronal origin. The results of the present paper confirm the findings that BDNF may represent the key target for olanzapine and PACAP

Role of transglutaminase 2 in PAC1 receptor mediated protection against hypoxia-induced cell death and neurite outgrowth in differentiating N2a neuroblastoma cells

The PAC1 receptor and tissue transglutaminase (TG2) play important roles in neurite outgrowth and modulation of neuronal cell survival. In this study, we investigated the regulation of TG2 activity by the PAC1 receptor in retinoic acid-induced differentiating N2a neuroblastoma cells. TG2 transamidase activity was determined using an amine incorporation and a peptide cross linking assay. In situ TG2 activity was assessed by visualising the incorporation of biotin-X-cadaverine using confocal microscopy. TG2 phosphorylation was monitored via immunoprecipitation and Western blotting. The role of TG2 in PAC1 receptor-induced cytoprotection and neurite outgrowth was investigated by monitoring hypoxia-induced cell death and appearance of axonal-like processes, respectively. The amine incorporation and protein crosslinking activity of TG2 increased in a time and concentration-dependent manner following stimulation with pituitary adenylate cyclase-activating polypeptide-27 (PACAP-27). PACAP-27 mediated increases in TG2 activity were abolished by the TG2 inhibitors Z-DON and R283 and by pharmacological inhibition of protein kinase A (KT 5720 and Rp-cAMPs), protein kinase C (Ro 31-8220), MEK1/2 (PD 98059), and removal of extracellular Ca2+. Fluorescence microscopy demonstrated PACAP-27 induced in situ TG2 activity. TG2 inhibition blocked PACAP-27 induced attenuation of hypoxia-induced cell death and outgrowth of axon-like processes. TG2 activation and cytoprotection were also observed in human SH-SY5Y cells. Together, these results demonstrate that TG2 activity was stimulated downstream of the PAC1 receptor via a multi protein kinase dependent pathway. Furthermore, PAC1 receptor-induced cytoprotection and neurite outgrowth are dependent upon TG2. These results highlight the importance of TG2 in the cellular functions of the PAC1 receptor

The Biological Activities of Cinnamon, Geranium and Lavender Essential Oils

Acinetobacter sp. represent an important cause of nosocomial infections. Their resistance to some antibiotics, their ability to survive on inanimate surfaces in the hospital environment and their ability to produce biofilms contributes to their virulence. The aim of the study was to determine the antibacterial properties of cinnamon, lavender and geranium essential oils against bacteria of the genus Acinetobacter isolated from several clinical materials and from the hospital environment. A comprehensive evaluation of the susceptibility of Acinetobacter sp. clinical strains to recommended antibiotics was performed. The constituents of cinnamon, lavender and geranium essential oils were identified by GC-FID-MS analysis, and their Minimal Inhibitory Concentrations (MICs) against tested clinical strains were determined by the micro-dilution broth method. In addition, the effects of essential oils on the viability of human microvascular endothelial cells (HMEC-1) and glioblastoma cell line (T98G) were evaluated. Cinnamon bark oil was the most active against clinical and environmental strains of Acinetobacter baumannii with MIC values ranging from 0.5 to 2.5 µL/mL. The MIC values for geranium oil were between 7.5 and 9.5 µL/mL, and between 10.5 and 13.0 µL/mL for lavender oil. These essential oils can be best employed in the fight against infections caused by bacteria from Acinetobacter genus as components of formulations for hygiene and disinfection of hospital environment

Diclofenac Diminished the Unfolded Protein Response (UPR) Induced by Tunicamycin in Human Endothelial Cells

Diclofenac belongs to the class of nonsteroidal anti-inflammatory drugs (NSAIDs), which are amongst the most frequently prescribed drugs to treat fever, pain and inflammation. Despite the presence of NSAIDs on the pharmaceutical market for several decades, epidemiological studies have shown new clinical applications of NSAIDs, and new mechanisms of their action were discovered. The unfolded protein response (UPR) activated under endoplasmic reticulum (ER) stress is involved in the pathophysiology of many diseases and may become a drug target, therefore, the study evaluated the effects of diclofenac on the tunicamycin-induced UPR pathways in endothelial cells. RT PCR analysis showed that diclofenac significantly inhibited activation of ER stress-responsive genes, i.e., CHOP/DITT3, GRP78/HSPA5 and DNAJB9. Additionally, the drug diminished the significant upregulation and release of the GRP78 protein, as evaluated using the ELISA assay, which was likely to be involved in the mechanism of the UPR activation resulting in apoptosis induction in endothelial cells. These results suggest the value of diclofenac as a factor capable of restoring the ER homeostasis in endothelial cells by diminishing the UPR

Dual targeting ligands - histamine H3 receptor ligands with monoamine oxidase B inhibitory activity - in vitro and in vivo evaluation

The clinical symptoms of Parkinson’s disease (PD) appear when dopamine (DA) concentrations in the striatum drops to around 20%. Simultaneous inhibitory effects on histamine H(3) receptor (H(3)R) and MAO B can increase DA levels in the brain. A series of compounds was designed and tested in vitro for human H(3)R (hH(3)R) affinity and inhibitory activity to human MAO B (hMAO B). Results showed different activity of the compounds towards the two biological targets. Most compounds had poor affinity for hH(3)R (K(i) > 500 nM), but very good inhibitory potency for hMAO B (IC(50) 90%) in rat cerebral cortex (CTX), and an increase in DA content in CTX and striatum. Moreover, compound 13 caused a slight increase in noradrenaline, but a reduction in serotonin concentration in CTX. Thus, compound 13 is a promising dual-active ligand for the potential treatment of PD although further studies are needed to confirm this