RESUMO
Gigaxonin is an E3 ubiquitin ligase that plays a role in cytoskeletal stability. Its role in cancer is not yet clearly understood. Our previous studies of head and neck cancer had identified gigaxonin interacting with p16 for NFκB ubiquitination. To explore its role in cancer cell growth suppression, we analyzed normal and tumor DNA from cervical and head and neck cancers. There was a higher frequency of exon 8 SNP (c.1293 C>T, rs2608555) in the tumor (46% vs. 25% normal, P = 0.011) pointing to a relationship to cancer. Comparison of primary tumor with recurrence and metastasis did not reveal a statistical significance. Two cervical cancer cell lines, ME180 and HT3 harboring exon 8 SNP and showing T allele expression correlated with higher gigaxonin expression, reduced in vitro cell growth and enhanced cisplatin sensitivity in comparison with C allele expressing cancer cell lines. Loss of gigaxonin expression in ME180 cells through CRISPR-Cas9 or siRNA led to aggressive cancer cell growth including increased migration and Matrigel invasion. The in vitro cell growth phenotypes were reversed with re-expression of gigaxonin. Suppression of cell growth correlated with reduced Snail and increased e-cadherin expression. Mouse tail vein injection studies showed increased lung metastasis of cells with low gigaxonin expression and reduced metastasis with reexpression of gigaxonin. We have found an association between C allele expression and RNA instability and absence of multimeric protein formation. From our results, we conclude that gigaxonin expression is associated with suppression of epithelial-mesenchymal transition through inhibition of Snail. SIGNIFICANCE: Our results suggest that GAN gene exon 8 SNP T allele expression correlates with higher gigaxonin expression and suppression of aggressive cancer cell growth. There is downregulation of Snail and upregulation of e-cadherin through NFκB ubiquitination. We hypothesize that exon 8 T allele and gigaxonin expression could serve as diagnostic markers of suppression of aggressive growth of head and neck cancer.
Assuntos
Neoplasias de Cabeça e Pescoço , Humanos , Animais , Camundongos , Regulação para Baixo/genética , Linhagem Celular Tumoral , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Transição Epitelial-Mesenquimal/genética , Caderinas/genéticaRESUMO
We have observed overexpression of PACS-1, a cytosolic sorting protein in primary cervical tumors. Absence of exonic mutations and overexpression at the RNA level suggested a transcriptional and/or posttranscriptional regulation. University of California Santa Cruz genome browser analysis of PACS-1 micro RNAs (miR), revealed two 8-base target sequences at the 3' terminus for hsa-miR-34a and hsa-miR-449a. Quantitative RT-PCR and Northern blotting studies showed reduced or loss of expression of the two microRNAs in cervical cancer cell lines and primary tumors, indicating dysregulation of these two microRNAs in cervical cancer. Loss of PACS-1 with siRNA or exogenous expression of hsa-miR-34a or hsa-miR-449a in HeLa and SiHa cervical cancer cell lines resulted in DNA damage response, S-phase cell cycle arrest, and reduction in cell growth. Furthermore, the siRNA studies showed that loss of PACS-1 expression was accompanied by increased nuclear γH2AX expression, Lys382-p53 acetylation, and genomic instability. PACS-1 re-expression through LNA-hsa-anti-miR-34a or -449a or through PACS-1 cDNA transfection led to the reversal of DNA damage response and restoration of cell growth. Release of cells post 24-h serum starvation showed PACS-1 nuclear localization at G1-S phase of the cell cycle. Our results therefore indicate that the loss of hsa-miR-34a and hsa-miR-449a expression in cervical cancer leads to overexpression of PACS-1 and suppression of DNA damage response, resulting in the development of chemo-resistant tumors.
Assuntos
Dano ao DNA , Resistencia a Medicamentos Antineoplásicos , MicroRNAs/metabolismo , RNA Neoplásico/metabolismo , Neoplasias do Colo do Útero/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Feminino , Fase G1 , Células HeLa , Humanos , MicroRNAs/genética , RNA Neoplásico/genética , Pontos de Checagem da Fase S do Ciclo Celular , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Proteínas de Transporte Vesicular/genéticaRESUMO
Lipids have been extensively used in formulations to enhance dissolution and bioavailability of poorly water-soluble as well as water-soluble drug molecules. The digestion of lipid-based formulations, in the presence of bile salts, phospholipids, and cholesterol, changes the lipid composition in vivo, resulting in the formation of different colloidal phases in the intestine. Therefore, in vitro characterization and evaluation of such formulations are critical in developing a successful formulation. This review covers comprehensive discussion on in vitro characterization techniques such as solubility, drug entrapment, thermal characterization, dissolution, and digestion of lipid-based formulations.
Assuntos
Sistemas de Liberação de Medicamentos , Lipídeos/química , Administração Oral , Animais , Química Farmacêutica , Composição de Medicamentos , Tamanho da Partícula , Fosfolipídeos , SolubilidadeRESUMO
Vancomycin has been associated with acute kidney injury in preclinical and clinical settings; however, the precise exposure profiles associated with vancomycin-induced acute kidney injury have not been defined. We sought to determine pharmacokinetic/pharmacodynamics indices associated with the development of acute kidney injury using sensitive urinary biomarkers. Male Sprague-Dawley rats received clinical-grade vancomycin or normal saline as an intraperitoneal injection. Total daily doses between 0 and 400 mg/kg of body weight were administered as a single dose or 2 divided doses over a 24-h period. At least five rats were utilized for each dosing protocol. A maximum of 8 plasma samples per rat were obtained, and urine was collected over the 24-h period. Kidney injury molecule-1 (KIM-1), clusterin, osteopontin, cystatin C, and neutrophil gelatinase-associated lipocalin levels were determined using Milliplex multianalyte profiling rat kidney panels. Vancomycin plasma concentrations were determined via a validated high-performance liquid chromatography methodology. Pharmacokinetic analyses were conducted using the Pmetrics package for R. Bayesian maximal a posteriori concentrations were generated and utilized to calculate the 24-h area under the concentration-time curve (AUC), the maximum concentration (Cmax), and the minimum concentration. Spearman's rank correlation coefficient (rs ) was used to assess the correlations between exposure parameters, biomarkers, and histopathological damage. Forty-seven rats contributed pharmacokinetic and toxicodynamic data. KIM-1 was the only urinary biomarker that correlated with both composite histopathological damage (rs = 0.348, P = 0.017) and proximal tubule damage (rs = 0.342, P = 0.019). The vancomycin AUC and Cmax were most predictive of increases in KIM-1 levels (rs = 0.438 and P = 0.002 for AUC and rs = 0.451 and P = 0.002 for Cmax). Novel urinary biomarkers demonstrate that kidney injury can occur within 24 h of vancomycin exposure as a function of either AUC or Cmax.
Assuntos
Injúria Renal Aguda/induzido quimicamente , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Vancomicina , Animais , Área Sob a Curva , Biomarcadores/sangue , Biomarcadores/urina , Moléculas de Adesão Celular/sangue , Clusterina/sangue , Cistatina C/sangue , Lipocalina-2/sangue , Masculino , Osteopontina/sangue , Ratos , Ratos Sprague-Dawley , Vancomicina/efeitos adversos , Vancomicina/sangue , Vancomicina/farmacocinéticaRESUMO
Vancomycin has been associated with acute kidney injury (AKI). However, the pharmacokinetic/toxicodynamic relationship for AKI is not well defined. Allometrically scaled vancomycin exposures were used to assess the relationship between vancomycin exposure and AKI. Male Sprague-Dawley rats received clinical-grade vancomycin in normal saline (NS) as intraperitoneal (i.p.) injections for 24- to 72-h durations with doses ranging 0 to 200 mg/kg of body weight divided once or twice daily. Urine was collected over the protocol's final 24 h. Renal histopathology was qualitatively scored. Urinary biomarkers (e.g., cystatin C, clusterin, kidney injury molecule 1 [KIM-1], osteopontin, lipocalin 2/neutrophil gelatinase-associated lipocalin 2) were assayed using a Luminex xMAP system. Plasma vancomycin concentrations were assayed by high-performance liquid chromatography with UV detection. A three-compartment vancomycin pharmacokinetic model was fit to the data with the Pmetrics package for R. The exposure-response in the first 24 h was evaluated using Spearman's nonparametric correlation coefficient (rs) values for the area under the concentration-time curve during the first 24 h (AUC0-24), the maximum concentration in plasma during the first 24 h (Cmax0-24 ), and the lowest (minimum) concentration in plasma after the dose closest to 24 h (Cmin0-24 ). A total of 52 rats received vancomycin (n = 42) or NS (n = 10). The strongest exposure-response correlations were observed between AUC0-24 and Cmax0-24 and urinary AKI biomarkers. Exposure-response correlations (rs values) for AUC0-24, Cmax0-24 , and Cmin0-24 were 0.37, 0.39, and 0.22, respectively, for clusterin; 0.42, 0.45, and 0.26, respectively, for KIM-1; and 0.52, 0.55, and 0.42, respectively, for osteopontin. However, no differences in histopathological scores were observed. Optimal sampling times after administration of the i.p. dose were 0.25, 0.75, 2.75, and 8 h for the once-daily dosing schemes and 0.25, 1.25, 14.5, and 17.25 h for the twice-daily dosing schemes. Our observations suggest that AUC0-24 or Cmax0-24 correlates with increases in urinary AKI biomarkers.
Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/urina , Biomarcadores/urina , Vancomicina/efeitos adversos , Vancomicina/farmacocinética , Animais , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Ratos Sprague-DawleyRESUMO
We and others have shown that the cystatin E/M gene is inactivated in primary human tumors, pointing to its role as a tumor suppressor gene. However, the molecular mechanism of tumor suppression is not yet understood. Using plasmid-directed cystatin E/M gene overexpression, a lentivirus-mediated tetracycline-inducible vector system, and human papillomavirus 16 (HPV 16) E6 and E7 gene-immortalized normal human epidermal keratinocytes, we demonstrated intracellular and non-cell-autonomous apoptotic growth inhibition of tumor cell lines and that growth inhibition is associated with cytoplasmic retention of NF-κB. We further demonstrated decreased phosphorylation of IκB kinase (IKKß) and IκBα in the presence of tumor necrosis factor alpha (TNF-α), confirming the role of cystatin E/M in the regulation of the NF-κB signaling pathway. Growth suppression of nude mouse xenograft tumors carrying a tetracycline-inducible vector system was observed with the addition of doxycycline in drinking water, confirming that the cystatin E/M gene is a tumor suppressor gene. Finally, immunohistochemical analyses of cervical carcinoma in situ and primary tumors have shown a statistically significant inverse relationship between the expression of cystatin E/M and cathepsin L and a direct relationship between the loss of cystatin E/M expression and nuclear expression of NF-κB. We therefore propose that the cystatin E/M suppressor gene plays an important role in the regulation of NF-κB.
Assuntos
Cistatina M/metabolismo , Citoplasma/metabolismo , Proteínas I-kappa B/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Neoplasias do Colo do Útero/patologia , Animais , Catepsina L/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Cistatina M/genética , Doxiciclina/administração & dosagem , Feminino , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos/farmacologia , Células HeLa , Humanos , Lentivirus/genética , Camundongos , Camundongos Nus , Transplante de Neoplasias , Fosforilação , Transdução de Sinais , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismoRESUMO
PURPOSE: The compatibility of vancomycin and piperacillin-tazobactam in concentrations typically used in extended-infusion dosing schemes was evaluated. METHODS: Piperacillin-tazobactam was reconstituted and diluted to concentrations of 33.75, 45, 50, 60, 67.5, 80, and 90 mg/mL. Vancomycin was diluted to concentrations of 4-8, 10, and 12 mg/mL. The resultant admixtures were visually observed after preparation against black and white backgrounds each hour between hours 1 through 4 and after 24 hours. Frozen products of each medication and brand-name Zosyn powder for reconstitution also were studied. Each combination of products and concentrations was tested for precipitation using simulated Y-site administration. Absorbance and microscopic analyses were performed to discern less perceptible incompatibilities in combinations that did not result in visual precipitation. Changes in absorbance were evaluated using two-way repeated-measures analysis of variance with post hoc Bonferroni corrections. RESULTS: No tested concentrations of piperacillin-tazobactam showed precipitations with vancomycin up to concentrations of 7 mg/mL. Piperacillin-tazobactam 80-90 mg/mL formed reversible precipitation with vancomycin 8 mg/mL. All tested concentrations of piperacillin-tazobactam formed a reversible precipitate with vancomycin 10 mg/mL. Irreversible precipitation was noted with all combinations of piperacillin-tazobactam and vancomycin 12 mg/mL. No significant changes in absorbance analyses were identified for all tested piperacillin-tazobactam concentrations and vancomycin 4-10 mg/mL compared with 0.9% sodium chloride injection (p > 0.05). Similar results were observed using frozen preparations and brand-name Zosyn. CONCLUSION: Visual, microscopic, and absorbance analyses showed no evidence of incompatibility when piperacillin-tazobactam 33.75-90 mg/mL was combined with vancomycin ≤7 mg/mL. Reversible and irreversible precipitates formed when piperacillin-tazobactam was combined with vancomycin ≥8 mg/mL.
Assuntos
Antibacterianos/química , Ácido Penicilânico/análogos & derivados , Vancomicina/química , Antibacterianos/administração & dosagem , Precipitação Química , Composição de Medicamentos/métodos , Incompatibilidade de Medicamentos , Humanos , Ácido Penicilânico/administração & dosagem , Ácido Penicilânico/química , Piperacilina/administração & dosagem , Piperacilina/química , Combinação Piperacilina e Tazobactam , Cloreto de Sódio/química , Fatores de Tempo , Vancomicina/administração & dosagemRESUMO
The objective of our investigational work was to develop a proliposomal formulation to improve the oral bioavailability of valsartan. Proliposomes were formulated by thin film hydration technique using different ratios of phospholipids:drug:cholesterol. The prepared proliposomes were evaluated for vesicle size, encapsulation efficiency, morphological properties, in vitro drug release, in vitro permeability and in vivo pharmacokinetics. In vitro drug-release studies were performed in simulated gastric fluid (pH 1.2) and purified water using dialysis bag method. In vitro drug permeation was studied using parallel artificial membrane permeation assay (PAMPA), Caco-2 monolayer and everted rat intestinal perfusion techniques. In vivo pharmacokinetic studies were conducted in male Sprague Dawley (SD) rats. Among the proliposomal formulations, F-V was found to have the highest encapsulation efficiency of 95.6 ± 2.9% with a vesicle size of 364.1 ± 14.9 nm. The in vitro dissolution studies indicated an improved drug release from proliposomal formulation, F-V in comparison to pure drug suspension in both, purified water and pH 1.2 dissolution media after 12 h. Permeability across PAMPA, Caco-2 cell and everted rat intestinal perfusion studies were higher with F-V formulation as compared to pure drug. Following single oral administration of F-V formulation, a relative bioavailability of 202.36% was achieved as compared to pure valsartan.
Assuntos
Desenho de Fármacos , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacocinética , Valsartana/administração & dosagem , Valsartana/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Células CACO-2 , Humanos , Lipossomos , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer, with 600,000 new cases every year worldwide. Although chemotherapeutics exist, five-year survival is only 50%. New strategies to overcome drug resistance are required to improve HNSCC treatment. Curcumin-difluorinated (CDF), a synthetic analog of curcumin, was packaged in liposomes and used to evaluate growth inhibition of cisplatin resistant HNSCC cell lines CCL-23R and UM-SCC-1R generated from the parental cell lines CCL-23 and UM-SCC-1 respectively. Growth inhibition in vitro and expression levels of the CD44 (cancer stem cell marker), cytokines, and growth factors were investigated after liposomal CDF treatment. The in vivo growth inhibitory effect of liposomal CDF was evaluated in the nude mice xenograft tumor model of UM-SCC-1R and the inhibition of CD44 was measured. Treatment of the resistant cell lines in vitro with liposomal CDF resulted in a statistically significant growth inhibition (p < 0.05). The nude mice xenograft study showed a statistically significant tumor growth inhibition of UM-SCC-1R cells and a reduction in the expression of CD44 (p < 0.05), indicating an inhibitory effect of liposomal CDF on CSCs. Our results demonstrate that delivery of CDF through liposomes may be an effective method for the treatment of cisplatin resistant HNSCC.
Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Curcumina/farmacologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Hidrocarbonetos Fluorados/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Cisplatino/farmacologia , Curcumina/análogos & derivados , Citocinas/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Receptores de Hialuronatos/genética , Lipossomos , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Proliposomes are phospholipid based drug delivery systems that are finding important applications in the field of pharmaceutics. Proliposomes have been extensively studied as a potential carrier for oral delivery of drugs with poor bioavailability, but the mechanism of absorption and cellular uptake pathways has not yet been clearly understood. An in-depth insight into the physical and biological behavior of proliposomes is necessary for designing an effective delivery system for enhancing the availability of drug at the intended site. Reformulation of sub optimal drugs using proliposomes has given an opportunity to improve the therapeutic indices of various drugs predominantly by altering their uptake mechanism. This work reviews the proliposomal drug delivery field, summarizes the success of proliposomes for the oral delivery of drugs with poor bioavailability; indicating the key issues to be addressed to affirm that proliposomes can effectively work as a drug carrier in clinical settings with a clear understanding of its behavior in biological environment, as they are now an established platform technology with considerable clinical acceptance.
Assuntos
Lipossomos , Administração Oral , Animais , Humanos , Lipídeos/química , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/químicaRESUMO
The molecular mechanism of p16-mediated senescence in cisplatin-treated cancer cells is not fully understood. Here we show that cisplatin treatment of head and neck cancer cells results in nuclear transport of p16 leading to a molecular modification of NFκB. Chromatin immunoprecipitation assays show that this modification is associated with the inhibition of NFκB interacting with its DNA binding sequences, leading to decreased expression of NFκB-transcribed proteins. LCMS proteomic analysis of LAP-TAP-purified proteins from HeLa cells containing a tetracycline-inducible GFP-S peptide-NFκB expression system identified gigaxonin, an ubiquitin E3 ligase adaptor, as an NFκB-interacting protein. Immunoblotting and siRNA studies confirmed the NFκB-gigaxonin interaction and the dependence of this binding on p16-NFκB binding. Using gel shift assays, we have confirmed p16-NFκB and gigaxonin-NFκB interactions. Furthermore, we have observed increased NFκB ubiquitination with cisplatin treatment that is abolished in the absence of p16 and gigaxonin expression. Analysis of 103 primary tumors has shown that increased nuclear p16 expression correlates with enhanced survival of head and neck cancer patients (p < 0.0000542), indicating the importance of nuclear p16 expression in prognosis. Finally, p16 expression is associated with reduced cytokine expression and the presence of human papilloma virus in chemoradiation-sensitive basaloid tumors. However, the absence of p16 expression is associated with enhanced cytokine expression and the absence of human papilloma virus in aggressive tumors. These results clearly demonstrate that nuclear p16 and gigaxonin play an important role in chemosensitivity of head and neck cancers through ubiquitination of NFκB.
Assuntos
Antineoplásicos/farmacologia , Senescência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Proteínas do Citoesqueleto/metabolismo , NF-kappa B/metabolismo , Ubiquitinação/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Ciclina D1/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/virologia , Papillomavirus Humano 16/fisiologia , Humanos , PrognósticoRESUMO
Objective of the present study was to develop a proliposomal formulation to decrease the hepatic first-pass metabolism of a highly metabolized drug. Lovastatin was chosen as the model drug. Proliposomes were prepared by mixing different ratios of phospholipids such as soy phosphatidylcholine (SPC), hydrogenated egg phosphatidylcholine (HEPC) and dimyristoyl phosphatidylglycerol (DMPG) individually with drug and cholesterol in an organic solvent. Proliposomal powder was obtained following evaporation of the solvent. The proliposomal powder was either filled into capsules or compressed into tablets. Physical characterization, in vitro drug transport studies and in vitro dissolution of formulations and pure drug was carried out. In vitro transport across the membrane was evaluated using parallel artificial membrane permeability assay (PAMPA). The extent of drug released from various proliposomal formulations in the first 30 min was 85%, 87% and 96% with DMPG, SPC and HEPC containing formulations respectively, while the pure drug formulation showed 48% drug release in the same period. In vivo studies were carried out in male Sprague-Dawley rats. Following single oral administration of the selected formulation (F9), a relative bioavailability of 162% was achieved compared to pure lovastatin. The study demonstrated that proliposomes can be used as a drug delivery system to decrease the hepatic first-pass metabolism.
Assuntos
Sistemas de Liberação de Medicamentos , Fígado/metabolismo , Lovastatina/metabolismo , Administração Oral , Animais , Disponibilidade Biológica , Lipossomos , Lovastatina/administração & dosagem , Lovastatina/química , Masculino , Ratos , Ratos Sprague-Dawley , ComprimidosRESUMO
AIM: To evaluate the effect of an active fraction from Leptadenia reticulata leaves on serum glucose and lipid profile in normal and diabetic rats. METHOD: Diabetes was induced by streptozotocin in Wistar rats. Petroleum ether, ethyl acetate, and ethanol extracts of Leptadenia reticulata leaves were administered orally at a dose of 200 mg·kg(-1), p.o. Metformin was used as standard anti diabetic drug (50 mg·kg(-1), p.o). The extract showing higher antidiabetic activity was subjected to column chromatography and led to the isolation of an active fraction, which was given trivial name Lr-1. Lr-1 (100 mg·kg(-1), p.o.) was studied for its hypoglycemic and hypolipidemic potential. RESULTS: The ethanol extract was found to lower the FBG level significantly (P < 0.05) in diabetic rats. Lr-1 caused a significant (P < 0.05) reduction in FBG level, and additionally it caused reduction in cholesterol, triglyceride levels, and an improvement in the HDL level in diabetic rats. CONCLUSION: Reduction in the FBG, cholesterol, triglyceride levels, and an improvement in the HDL by Lr-1 indicates that Lr-1 has antidiabetic activity, along with cardioprotective potential, and provides a scientific rationale for the use as an antidiabetic agent.
Assuntos
Apocynaceae , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Lipídeos/sangue , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Colesterol/sangue , HDL-Colesterol/sangue , Diabetes Mellitus Experimental/sangue , Hipoglicemiantes/farmacologia , Masculino , Extratos Vegetais/farmacologia , Folhas de Planta , Ratos Wistar , Triglicerídeos/sangueRESUMO
PURPOSE: The physical compatibility of vancomycin and piperacillin sodium-tazobactam at dosing concentrations commonly administered during prolonged infusions was studied. METHODS: Concentrations of vancomycin and piperacillin sodium-tazobactam typically used in prolonged infusions were evaluated. Vancomycin hydrochloride and piperacillin sodium-tazobactam were reconstituted with 0.9% sodium chloride injection and diluted to the following concentrations: vancomycin, 4 mg/mL; piperacillin sodium 30 mg/mL plus tazobactam 3.75 mg/mL; and piperacillin sodium 40 mg/mL plus tazobactam 5 mg/mL. Combinations of vancomycin and piperacillin sodium-tazobactam were tested using simulated Y-site administration; phenytoin served as a positive control for precipitation with vancomycin. Each combination was prepared in triplicate, alternating the order of drug addition, and stored without light protection at room temperature. The resultant admixtures were microscopically observed and subjected to particle-size and turbidity analyses for five days. Statistical analyses were performed using two-way repeated measures analysis of variance with conservative Bonferroni corrections for multiple comparisons. RESULTS: Vancomycin was compatible with piperacillin sodium-tazobactam in the concentrations tested. No particulate matter was observed by the unaided eye. Similarly, the antibiotic admixtures displayed no differences microscopically, by particle-size analysis, or by turbidity analysis when compared with negative controls at five days. CONCLUSION: Vancomycin 4 mg/mL and piperacillin sodium 30 mg/mL plus tazobactam 3.75 mg/mL or piperacillin sodium 40 mg/mL plus tazobactam 5 mg/mL were physically compatible during simulated Y-site injection at room temperature without light protection for five days.
Assuntos
Antibacterianos/química , Antibacterianos/farmacocinética , Ácido Penicilânico/análogos & derivados , Vancomicina/química , Vancomicina/farmacocinética , Antibacterianos/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Esquema de Medicação , Combinação de Medicamentos , Estabilidade de Medicamentos , Humanos , Infusões Intravenosas/métodos , Soluções Isotônicas , Nefelometria e Turbidimetria , Ácido Penicilânico/administração & dosagem , Ácido Penicilânico/química , Ácido Penicilânico/farmacocinética , Piperacilina/administração & dosagem , Piperacilina/química , Piperacilina/farmacocinética , Combinação Piperacilina e Tazobactam , Fatores de Tempo , Vancomicina/administração & dosagemRESUMO
Here, we investigate the potential role of the PARP inhibitor rucaparib (CO-338, formerly known as AG014699 and PF-01367338) for the treatment of sporadic ovarian cancer. We studied the growth inhibitory effects of rucaparib in a panel of 39 ovarian cancer cell lines that were each characterized for mutation and methylation status of BRCA1/2, baseline gene expression signatures, copy number variations of selected genes, PTEN status, and sensitivity to platinum-based chemotherapy. To study interactions with chemotherapy, we used multiple drug effect analyses and assessed apoptosis, DNA fragmentation, and γH2AX formation. Concentration-dependent antiproliferative effects of rucaparib were seen in 26 of 39 (67%) cell lines and were not restricted to cell lines with BRCA1/2 mutations. Low expression of other genes involved in homologous repair (e.g., BCCIP, BRCC3, ATM, RAD51L1), amplification of AURKA or EMSY, and response to platinum-based chemotherapy was associated with sensitivity to rucaparib. Drug interactions with rucaparib were synergistic for topotecan, synergistic, or additive for carboplatin, doxorubicin or paclitaxel, and additive for gemcitabine. Synergy was most pronounced when rucaparib was combined with topotecan, which resulted in enhanced apoptosis, DNA fragmentation, and γH2AX formation. Importantly, rucaparib potentiated chemotherapy independent of its activity as a single agent. PARP inhibition may be a useful therapeutic strategy for a wider range of ovarian cancers bearing deficiencies in the homologous recombination pathway other than just BRCA1/2 mutations. These results support further clinical evaluation of rucaparib either as a single agent or as an adjunct to chemotherapy for the treatment of sporadic ovarian cancer.
Assuntos
Histonas/metabolismo , Indóis/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Poli(ADP-Ribose) Polimerases/metabolismo , Apoptose/efeitos dos fármacos , Proteína BRCA2/genética , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Histonas/genética , Humanos , Mutação , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Inibidores de Poli(ADP-Ribose) Polimerases , Topotecan/administração & dosagem , Ubiquitina-Proteína Ligases/genéticaRESUMO
The aim of this study was to develop and characterize phospholipid bearing pellets for a poorly water-soluble drug, nisoldipine. Pellets were prepared using extrusion-spheronization technique containing microcrystalline cellulose, soy phosphatidylcholine (SPC), granulating fluid and lactose. Operational parameters such as extrusion speed, spheronization speed and residence time were evaluated. Optimal extrusion speed was found to be 50 rpm with a spheronization speed of 60 Hz and residence time of 2 min. Pellets were characterized for their size, shape, density, flow properties, friability, moisture content, surface morphology and thermal properties. Pellets were evaluated for their assay and in vitro drug release. Mathematical modeling was used to determine the release patterns of the pellets. Pellets were found to be spherical, 600-850 µm size with <0.01% friability and had >70% yield. Scanning electron microscopic (SEM) studies showed a smoother external surface and a porous internal matrix. SPC incorporated pellets resulted in improved dissolution of the drug. Pellets with SPC (20 and 30%) released >90% of the drug within 24 h. The dissolution profiles of the pellets were best fitted to Korsmeyer-Peppas kinetic model. In this study, we could successfully incorporate a lipid and a water-insoluble drug into a pellet formulation with improved dissolution profile.
Assuntos
Sistemas de Liberação de Medicamentos , Nisoldipino/química , Fosfatidilcolinas/química , Bloqueadores dos Canais de Cálcio/química , Varredura Diferencial de Calorimetria , Celulose/química , Excipientes/química , Microscopia Eletrônica de Varredura , Modelos Teóricos , Solubilidade , ComprimidosRESUMO
The recent identification of activating fibroblast growth factor receptor 2 (FGFR2) mutations in endometrial cancer has generated an opportunity for a novel target-based therapy. Here, we explore the therapeutic potential of 2 FGFR inhibitors, the multikinase inhibitor dovitinib (TKI258) and the more selective FGFR inhibitor NVP-BGJ398 for the treatment of endometrial cancer. We examined the effects of both inhibitors on tumor cell growth, FGFR2 signaling, cell cycle, and apoptosis using a panel of 20 molecularly characterized human endometrial cancer cell lines. Anchorage-independent growth was studied using soft agar assays. In vivo studies were conducted using endometrial cancer xenograft models. Cell lines with activating FGFR2 mutations (S252W, N550K) were more sensitive to dovitinib or NVP-BGJ398 when compared with their FGFR2 wild-type counterparts (P = 0.073 and P = 0.021, respectively). Both agents inhibited FGFR2 signaling, induced cell-cycle arrest, and significantly increased apoptosis in FGFR2-mutant lines. In vitro, dovitinib and NVP-BGJ398 were both potent at inhibiting cell growth of FGFR2-mutant endometrial cancer cells, but the activity of dovitinib was less restricted to FGFR2-mutant lines when compared with NVP-BGJ398. In vivo, dovitinib and NVP-BGJ398 significantly inhibited the growth of FGFR2-mutated endometrial cancer xenograft models. In addition, dovitinib showed significant antitumor activity in FGFR2 wild-type endometrial cancer xenograft models including complete tumor regressions in a long-term in vivo study. Dovitinib and NVP-BGJ398 warrant further clinical evaluation in patients with FGFR2-mutated endometrial cancer. Dovitinib may have antitumor activity in endometrial cancer beyond FGFR2-mutated cases and may permit greater flexibility in patient selection.
Assuntos
Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Neoplasias do Endométrio/metabolismo , Compostos de Fenilureia/farmacologia , Pirimidinas/farmacologia , Quinolonas/farmacologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Benzimidazóis/administração & dosagem , Benzimidazóis/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Feminino , Humanos , Concentração Inibidora 50 , Camundongos , Mutação , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/química , Pirimidinas/administração & dosagem , Pirimidinas/química , Quinolonas/administração & dosagem , Quinolonas/química , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Transdução de Sinais/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Globally, in the last three decades of medical research, the use of liposomes as carrier for anti-HIV/AIDS drugs is gaining prominence. These potential anti-HIV nanocarriers are concentric lipid bilayers which can be fabricated to protect molecules and to target the drugs to specific sites, which is the reason behind their popularity in the antiretroviral drug delivery. The development of an effective drug delivery system such as liposomes presents an opportunity to circumvent the many challenges associated with antiretroviral drug therapy. The physiochemical properties of liposomes such as size, charge, and lipid composition significantly affect the liposomal efficiency. These nanocarriers offer advantages such as drug loading both in aqueous region and within the bilayer of the vesicles, act as solubilizing agents, protect drug from degradation in the body, allow modification of the pharmacokinetic and tissue distribution patterns of the drug, provide drug targeting, and have low immunogenicity, biocompatibility, and cell specificity. Different types of liposome-based delivery systems, such as cationic, anionic, sterically stabilized, and immunoliposomes, have been studied for the anti-HIV/AIDS drug delivery. Liposomes, however, face challenges with regard to their use in antiretroviral drug delivery such as limited hydrophilic drug-loading capacity, issues related to physical and biologic stability, poor scale-up, cost, short shelf life, and toxicity. Numerous patented strategies have been granted in the USA and around the world related to these anti-HIV nanocarriers. In the present article, we have discussed the general physiological aspects of the HIV infection, relevance of the nanocarrier, liposomes, in the treatment of this disease and some recently awarded US patents and patent applications of these liposomal delivery systems for anti-HIV drugs.
RESUMO
Approximately 25,000 ovarian cancers are diagnosed in the United States annually, and 75% of cases are in the advanced stage when they are largely incurable. There is a critical need for improved early detection tools and development of novel treatments. Recently, we showed that among 20q13-amplified genes in ovarian cancer, ADRM1 overexpression was the most highly correlated with amplification and was significantly upregulated with respect to stage, recurrence, and metastasis. In addition, overexpression of ADRM1 correlated significantly with shorter time to recurrence and overall survival. Herein, array-CGH and microarray expression of ovarian cancer cell lines provides evidence consistent with the primary tumor data that ADRM1 is a 20q13 amplification target. Knockdown of ADRM1 in amplified ovarian cell-line OAW42 results in downregulation of growth factor GIPC1 and upregulation of tumor-suppressor RECK RNA and protein. In our dataset of 141 ovarian primary tumors, ADRM1 overexpression significantly correlates with GIPC1 overexpression. In addition, there is a significant anticorrelation between ADRM1 overexpression and RECK expression. Further research is necessary to determine whether targeting knockdown of ADRM1 in 20q13-amplified ovarian cancers results in growth inhibition and tumor suppression via downstream targets GIPC1 and RECK.