Determination of mebudipine in human plasma by liquid chromatography�tandem mass spectrometry

In previous studies, mebudipine, a dihydropyridine calcium channel blocker, showed a considerable potential to be used in cardiovascular diseases. The aim of the current study was to develop a valid method using reversed-phase high performance liquid chromatography coupled with electrospray ionization mass spectrometry to assay mebudipine in the human plasma. Separation was achieved on a Zorbax Eclipse® C18 analytical column using a mobile phase consisted of methanol/water (90:10, v/v). The flow rate was 0.6 mL/min and carbamazepine was used as an internal standard (IS). This method involved the use of M +Na+ ions of mebudipine and IS at m/z 411 and 259, respectively with the selected ion monitoring (SIM) mode. There were no interfering peaks from endogenous components in blank plasma chromatograms. Standard curves were linear (r2>0.99) between 5 to 100 ng/mL. The mean extraction efficiency was about 84% and the limit of quantification for mebudipine was 5 ng/mL in plasma. The coefficient of variation and error at all of the intra-day and inter-day assessments were less than 11%. The results indicated that this method is a fast, accurate, sensitive, selective and reliable method for the determination of mebudipine in the human plasma. The assay method has been successfully used to estimate plasma concentration of mebudipine after the oral administration of 2.5 mg tablet in healthy adults. © 2015 by School of Pharmacy Shaheed Beheshti University of Medical Sciences and Health Services

Improved HPLC method for determination of four PPis, omeprazole, pantoprazole, lansoprazole and rabeprazole in human plasma

PURPOSE: To develop a simple and rapid HPLC method for measuring of four proton-pump inhibitors (PPIs), omeprazole (OPZ), pantoprazole (PPZ), lansoprazole (LPZ) and rabeprazole (RPZ) concentrations in human plasma. METHODS: Following a single step liquid-liquid extraction analytes along with an internal standard (IS) were separated using an isocratic mobile phase of phosphate buffer (10 mM)/acetonitrile (53/47, v/v adjusted pH to 7.3 with triethylamine) at flow rate of 1 mL/min on reverse phase TRACER EXCEL 120 ODS-A column at room temperature. RESULTS: Total analytical run time for selected PPIs was 10 min. The assays exhibited good linearity (r2>0.99) over the studied range of 20 to 2500 ng/mL for OPZ, 20 to 4000 ng/mL for PPZ, 20 to 3000 ng/mL for LPZ and 20 to 1500 ng/mL for RPZ. The recovery of method was equal or greater than 80 and lower limit of quantification (LLOQ) was 20 ng/mL for four PPIs. Coefficient of variation and error at all of the intra-day and inter-day assessment were less than 9.2 for all compounds. CONCLUSIONS: The results indicated that this method is a simple, rapid, precise and accurate assay for determination of four PPIs concentrations in human plasma. This validated method is sensitive and reproducible enough to be used in pharmacokinetic studies and also is time- and cost-benefit when selected PPIs are desired to be analyzed

The role of Olea Europaea L. Fruit on A2780, A172 and HFFF2 proliferation

Olea europaea L. commonly known as olive has been traditionally used for the prevention and treatment of many diseases since ancient times. Olive has been reported to possess a broad spectrum of pharmacological properties. In the present study, we investigated the activity of aqueous extract of Olea europaea L. fruit at various concentrations on A2780, A172, and HFFF2 cell lines proliferation by MTT assay. Aqueous extract of olive significantly increased cell proliferation in a dose dependent manner in the cell lines. It has been previously reported that olive has chemoproventive and anti-tumor effects. These disagreements can be explained by differences in cell line properties, type of olive and different solvents in the extracts. However, further investigation is needed to clarify the exact role of olive in cell proliferation and cancer. In this study fruit extract of Olea europaea L. showed more activatory effects on A2780 cell line in comparison with A172 and HFFF2. These differences in the activatory effects may be related to the activation of different signaling pathways in different cell lines. © 2016, Iranian Association of Pharmaceutical Scientists. All rights reserved

Design and evaluation of a novel nanodrug delivery system for reducing the side effects of clomiphene citrate on endometrium

Background: Stimulation of ovulation with clomiphene citrate can cause side effects on endometrial receptivity. Formulation with nano-size may be an alternative therapy for women with ovulatory disorders. In this study, we investigated sustained-release clomiphene citrate by using Phosal-based formulation (PBF) and evaluate its decreased side effect on the endometrial receptivity. Methods: In the in-vitro study, CC loaded PBF was analyzed using Zetasizer, Fourier-transform infrared spectroscopy (FTIR), and Transmission electron microscopy (TEM). In the in-vivo study, 24 female mice were randomly divided into three groups: CC (5 mg/kg), CC/PBF (5 mg/kg) and SS (1 ml) daily administered and injected with 5 IU HCG and mated after two days. At day 4.5, pregnant mice were euthanized and endometrial tissue was extracted for quantitative polymerase chain reaction (Q-PCR) analysis. Results: The optimized PBF contained Phosal 50PG/glycerol in a 2:8 ratios (w/w) and the particle size of optimum formulation was 67 ± 0.30551 nm and the release of CC from CC-containing PBF was slightly faster in the first 24 h; wherein, 29 of CC was released, and 76 of CC was released up to 120 h. The mRNA levels of leukemia inhibitory factor (LIF), leukemia inhibitory factor receptor alpha (LIFR), HOXA10, Heparin-binding epidermal growth factor (HB-EGF), and epidermal growth factor (EGF) were significantly upregulated and MUC1 and PGR mRNA levels were significantly downregulated in the CC-containing PBF-treated animals compared with only CC group (P < 0.05). Conclusion: Sustained release formulation of clomiphene citrate increased its targeting efficiency and improved the impact of the CC on implantation. Figure not available: see fulltext. © 2019, Springer Nature Switzerland AG

The Insulin-Like Growth Factor System in the Long-Lived Naked Mole-Rat.

Naked mole-rats (Heterocephalus glaber) (NMRs) are the longest living rodents known. They show negligible senescence, and are resistant to cancers and certain damaging effects associated with aging. The insulin-like growth factors (IGFs) have pluripotent actions, influencing growth processes in virtually every system of the body. They are established contributors to the aging process, confirmed by the demonstration that decreased IGF signaling results in life-extending effects in a variety of species. The IGFs are likewise involved in progression of cancers by mediating survival signals in malignant cells. This report presents a full characterization of the IGF system in the NMR: ligands, receptors, IGF binding proteins (IGFBPs), and IGFBP proteases. A particular emphasis was placed on the IGFBP protease, pregnancy-associated plasma protein-A (PAPP-A), shown to be an important lifespan modulator in mice. Comparisons of IGF-related genes in the NMR with human and murine sequences indicated no major differences in essential parts of the IGF system, including PAPP-A. The protease was shown to possess an intact active site despite the report of a contradictory genome sequence. Furthermore, PAPP-A was expressed and translated in NMRs cells and retained IGF-dependent proteolytic activity towards IGFBP-4 and IGF-independent activity towards IGFBP-5. However, experimental data suggest differential regulatory mechanisms for PAPP-A expression in NMRs than those described in humans and mice. This overall description of the IGF system in the NMR represents an initial step towards elucidating the complex molecular mechanisms underlying longevity, and how these animals have evolved to ensure a delayed and healthy aging process

Antibodies to insulin-like growth factor I receptor

International Application No.: PCT/AU2007/000168The present invention relates to an antibody to insulin-like growth factor I receptor, or an antigen-binding portion of the antibody. The antibody, or the antigen-binding portion, bind to an epitope located in the cysteine-rich domain of the alpha-subunit of the insulin-like growth factor I receptor, and the antibody or the antigen-binding portion modulates IGF-I mediated proliferation of an IGF-I dependent cell.http://www.wipo.int/patentscopedb/en/fetch.jsp?LANG=ENG&DBSELECT=PCT&SERVER_TYPE=19&SORT=1209482-SCORE&TYPE_FIELD=256&IDB=0&IDOC=1479628&C=00&ELEMENT_SET=BASICHTML-ENG&RESULT=3&TOTAL=3&START=1&DISP=25&FORM=SEP-0/HITNUM,B-ENG,DP,MC,PA,ABSUM-ENG,SCORE&SEARCH_IA=AU2007000168&QUERY=%22booker%2c+grant%2

Production and characterization of monoclonal antibodies against insulin-like growth factor type 1 receptor

The type 1 insulin-like growth factor receptor (IGF-1R) has been extensively reported to play an important role in cancer. Activation of the IGF-1R by IGF-I and IGF-II binding to the extracellular domains of the receptor induces mitogenic and anti-apoptotic effects, which are important events in tumor growth and survival. Several cancer cell types overexpress IGF-1R, suggesting a possible use of monoclonal antibodies (MAbs) against IGF-1R as diagnostic reagents. Here, we report the production and characterization of two independent MAbs, namely 7C2 and 9E11, generated by immunizing mice with the soluble extracellular part of this receptor (amino acids 1-906). Both MAbs bind to membrane bound IGF-1R and do not cross-react with insulin receptor isoforms, IR-A and IR-B expressed on IGF-1R() cells. MAbs 7C2 and 9E11 stained the IGF- 1R on frozen or paraffin-embedded tissue sections or frozen cells. The MAbs 7C2 and 9E11 immunoprecipitated the IGF-1R from P6 cell lysates (cells overexpressing human IGF-1R) and could detect non-reduced intact IGF-1R on immunoblots. However, the MAbs were not able to detect reduced and denatured receptor alpha and beta chains. Sequencing of the heavy- and light-chain variable regions revealed that the 7C2 and 9E11 CDR amino acid sequences are different but result in antibodies with similar properties. MAbs 7C2 and 9E11 are therefore potentially useful diagnostic tools and could be of therapeutic use for humans in the future.Mehrnaz Keyhanfar, Briony E. Forbes, Leah J. Cosgrove, John C. Wallace, Grant W. Bookerhttp://www.liebertonline.com/doi/abs/10.1089/hyb.2006.25.23

Commentary on prevention a possible drug�drug interaction: Is concurrent administration of orlistat and pioglitazone increase the risk of durg�induced hepatotoxicity?

Background: Drug-drug interactions (DDIs) are an emerging threat to public health and are difficult to detect. To prevent DDIs and their burden, the possible DDIs should be kept in mind. We know that the obesity predisposes to the development of insulin resistance and type 2 diabetes. Therefore, combinational uses of antiobesity drugs and glucose? lowering drugs are very common. As the hepatotoxicity of both pioglitazone (an antidiabetic drug) and orlistat (an antiobesity drug) has been shown in some cases, the aim of this study was to evaluate the interaction of pioglitazone and orlistat in human hepatocellular cell line human hepatocellular carcinoma (HepG2) cells to determine their effect on liver toxicity. Methods: Human hepatocellular carcinoma cells were treated with 25 µM Pioglitazon (Pio), 20 µ Orlistat (Orl) pioglitazone, orlistat or combination of them. The MTT assay was used to assess cell viability. Results: Pioglitazone and orlistat combination caused a loss of HepG2 cell viability. While pioglitazone (25 µ and orliatat (20 µ alone decreased the cell viability around 91 and 85 respectively (notsignificant, P> 0.05), the combination of these two drugs reduced the amount of viable cells to 55 which was significant when compared with each drug alone (P < 0.001). Conclusions: Revealing the significant loss of viability of HepG2 cells in the combination use of pioglitazone and orlistat indicates these two drugs should not be administered at the same time to prevent their hepatotoxic effects especially in patients with liver dysfunction. © 2015 Emzhik M

Hippocampal and prefrontal cortical NMDA receptors mediate the interactive effects of olanzapine and lithium in memory retention in rats: the involvement of CAMKII-CREB signaling pathways

Rationale: Treatment of bipolar disorder (BPD) with lithium and olanzapine concurrent administration is a major medicine issue with the elusive neurobiological mechanisms underlying the cognitive function. Objective: To clarify the precise mechanisms involved, the possible role of the hippocampus (HPC) and prefrontal cortical (PFC) NMDA receptors and CAMKII-CREB signaling pathway in the interactive effects of lithium and olanzapine in memory consolidation was evaluated. The dorsal hippocampal CA1 regions of adult male Wistar rats were bilaterally cannulated and a step-through inhibitory avoidance apparatus was used to assess memory consolidation. The changes in p-CAMKII/CAMKII and p-CREB/CREB ratio in the HPC and the PFC were measured by Western blot analysis. Results: Post-training administration of lithium (20, 30, and 40 mg/kg, i.p.) dose-dependently decreased memory consolidation whereas post-training administration olanzapine (2 and 5 mg/kg, i.p.) increased memory consolidation. Post-training administration of certain doses of olanzapine (1, 2, and 5 mg/kg, i.p.) dose-dependently improved lithium-induced memory impairment. Post-training administration of ineffective doses of the NMDA (10�5 and 10�4 μg/rat, intra-CA1) plus an ineffective dose of olanzapine (1 mg/kg, i.p.) dose-dependently improved the lithium-induced memory impairment. Post-training microinjection of ineffective doses of the NMDA (10�5 and 10�4 μg/rat, intra-CA1) dose-dependently potentiated the memory improvement induced by olanzapine (1 mg/kg, i.p.) on lithium-induced memory impairment which was associated with the enhancement of the levels of p-CAMKII and p-CREB in the HPC and the PFC. Post-training microinjection of ineffective doses of the noncompetitive NMDA receptor antagonist, MK-801 (0.0625 and 0.0125 μg/rat, intra-CA1), dose-dependently decreased the memory improvement induced by olanzapine (5 mg/kg, i.p.) on lithium-induced memory impairment which was related to the reduced levels of HPC and PFC CAMKII-CREB. Conclusion: The results strongly revealed that there is a functional interaction among lithium and olanzapine through the HPC and the PFC NMDA receptor mechanism in memory consolidation which is mediated with the CAMKII-CREB signaling pathway. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature