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1.
BMC Ophthalmol ; 19(1): 29, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30678648

RESUMO

BACKGROUND: Bone wax is the most widely used hemostatic bone sealant because of its availability, ease of use, immediate action, and minimal adverse effects. Several complications have been reported to be associated with the use of bone wax, such as infection, osteohypertrophy, pain, granuloma formation, allergic reaction, and thrombosis. Here, we present a rare complication, namely, bone wax migration, which developed after a craniotomy on a patient who had a frontal sinus abnormality. CASE PRESENTATION: A 51-year-old woman complained of pain and swelling in her left eye accompanied by difficulty opening the left eyelid after undergoing a craniotomy. An examination revealed left eye proptosis with ptosis, eyelid swelling, and increases in intraorbital pressure and intraocular pressure (IOP). According to a CT and an MRI of the orbit, we found that the intraoperative bone wax had migrated to the orbit, thereby causing compression. We also found that the basal frontal sinus of the patient was congenitally defective, which may have induced the migration of the bone wax. Given that the patient recently underwent a craniotomy and given the risks associated with orbital surgery, she refused to undergo a surgery to remove the bone wax. Thus, the patient was administered mannitol intravenously daily, accompanied by topical Timolol, to reduce the intraorbital pressure and IOP. This treatment led to a gradual decrease in IOP and intraorbital pressure, and these parameters remained stable after treatment ended. During the 6-month follow-up, the best corrected visual acuity improved, and ptosis and restricted eye movements also improved significantly. CONCLUSIONS: We report a case of bone wax migration that developed after a craniotomy on a patient who had a congenital defect in the basal frontal sinus. Extra caution should be taken when using bone wax, and a comprehensive understanding of the patient's intracranial anatomy is important for decreasing the incidence of bone wax migration. Additionally, when a patient presents with symptoms of ocular compression, bone wax migration should be considered in addition to typical radiological changes.


Assuntos
Blefaroptose/etiologia , Craniotomia/efeitos adversos , Migração de Corpo Estranho/complicações , Seio Frontal/cirurgia , Órbita/patologia , Palmitatos/efeitos adversos , Ceras/efeitos adversos , Feminino , Seio Frontal/anormalidades , Humanos , Pessoa de Meia-Idade , Hipertensão Ocular/etiologia , Palmitatos/farmacocinética , Complicações Pós-Operatórias/etiologia , Ceras/farmacocinética
2.
Biomed Pharmacother ; 110: 181-189, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30469082

RESUMO

Turmeric is a well-known functional food exhibiting multiple biological activities in health and disease. However, low aqueous solubility and poor bioavailability limit its therapeutic potential. Herein, we investigated the utility of nanoemulsions as a carrier to improve the efficacy of turmeric. Compared with turmeric extract (TE), 5% TE-loaded nanoemulsion (TE-NE), which contains 20-fold lower curcumin content than TE, achieved similar inhibition of palmitate-induced lipotoxicity in HepG2 cells. Exposure of HepG2 cells to 5% TE-NE also suppressed the palmitate-induced accumulation of lipid vacuoles and reactive oxygen species comparably with TE, and was accompanied by decreased levels of sterol regulatory element-binding protein (SREBP)-1, peroxisome proliferator-activated receptor-γ2 (PPAR-γ2), cleaved caspase-3, and poly (ADP-ribose) polymerase (PARP). Consistent with these effects in HepG2 cells, oral administration of 5% TE-NE to mice fed a high fat diet (HFD) markedly suppressed lipid accumulation in liver, leading to a significant reduction in body weight and adipose tissue weight, equivalent to the effects observed with TE. Compared with TE, 5% TE-NE also equivalently inhibited the levels of SREBP-1, PPAR-γ2, cleaved caspase-3, and PARP in the liver of mice fed a HFD. Furthermore, TE and 5% TE-NE significantly improved serum lipid profiles in a similar manner. These observations indicate that nanoemulsions can improve the efficacy of turmeric, thereby eliciting more potent biological efficacy against palmitate- and high fat diet (HFD)-induced cellular damage.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Emulsões/administração & dosagem , Nanopartículas/administração & dosagem , Obesidade/tratamento farmacológico , Palmitatos/administração & dosagem , Extratos Vegetais/administração & dosagem , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Curcuma , Relação Dose-Resposta a Droga , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Emulsões/metabolismo , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/metabolismo , Obesidade/etiologia , Obesidade/metabolismo , Palmitatos/farmacocinética , Extratos Vegetais/farmacocinética , Resultado do Tratamento
3.
J Nutr Biochem ; 59: 29-36, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29960114

RESUMO

Metabolic profiling studies have highlighted increases in the plasma free fatty acid (FFA) and branched-chain amino acid (BCAA) concentrations, which are hallmarks of the obese and insulin-resistant phenotype. However, little is known about how the increase of the BCAA concentration modifies the metabolic fate of FFA, and vice versa, in adipocytes. Therefore, we incubated differentiated 3T3-L1 adipocytes or primary adipocytes from rats fed a control or a high-fat diet with: (1) 0, 250, 500 and 1000 µM of leucine and determined the oxidation and incorporation of [1-14C]-palmitate into lipids or proteins or (2) 0, 250, 500 or 1000 µM of palmitate and evaluated the oxidation and incorporation of [U-14C]-leucine into lipids or proteins. Leucine decreased palmitate oxidation and increased its incorporation into the lipid fraction in adipocytes; the latter was reduced in adipocytes from obese rats. However, palmitate increased leucine oxidation in adipocytes as well as reduced leucine incorporation into the protein and lipid fractions in adipocytes from obese rats. These results demonstrate that leucine modifies the metabolic fate of palmitate, and vice versa, in adipocytes and that the metabolic interaction between leucine and palmitate catabolism is altered in adipocytes from obese rats.


Assuntos
Adipócitos/metabolismo , Leucina/metabolismo , Obesidade/metabolismo , Palmitatos/metabolismo , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Animais , Carnitina O-Palmitoiltransferase/genética , Dieta Hiperlipídica/efeitos adversos , Relação Dose-Resposta a Droga , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Leucina/administração & dosagem , Leucina/farmacocinética , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Proteínas de Membrana Transportadoras/genética , Camundongos , Transportadores de Ácidos Monocarboxílicos , Obesidade/patologia , Palmitatos/administração & dosagem , Palmitatos/farmacocinética , Enzima Bifuncional do Peroxissomo/genética , Ratos Endogâmicos , Ratos Sprague-Dawley
4.
Eur J Pharm Sci ; 113: 185-192, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28890202

RESUMO

We have optimized a formulation of a prodrug of dexamethasone (DXM), dexamethasone palmitate (DXP) for pulmonary delivery as a dry powder. Formulations were prepared by spray drying DXP with 1,2-Dipalmitoyl-sn-Glycero-3-Phosphocholine (DPPC) and Hyaluronic Acid (HA) as excipients. Large porous particles around 13 µm were produced with a tap density of 0.05g/cm3 and a Fine particle fraction around 40%. The palmitate moiety favors DXP insertion into DPPC bilayers therefore limiting its in vitro release as shown by differential scanning calorimetry. After administering DXP powder intratracheally to rats by insufflation, bronchoalveolar lavage fluid (BALF) and blood samples were collected up to 24h and DXP and DXM concentrations were determined by HPLC analysis after extraction. PK parameters were evaluated according to a non-compartmental model. We observe that DXP remains for up to 6h in the epithelial lining fluid (ELF) of the lungs at very high concentration. In addition, DXP concentration decreases according to two characteristic times. Consequently, DXM can be detected at rather important concentration in ELF up to 24h. The passage of DXP from the lungs to the bloodstream is very poor whereas DXM seems to be absorbed in the blood more easily. These results suggest that once administered DXP undergoes two different processes: hydrolysis into DXM due to the presence of esterases in the lungs and distribution in the lung tissue. This formulation appears promising to reduce systemic exposure and prolong the effect of the drug locally.


Assuntos
Corticosteroides/química , Química Farmacêutica/métodos , Dexametasona/farmacocinética , Palmitatos/farmacocinética , Pós/química , 1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , 1,2-Dipalmitoilfosfatidilcolina/química , Administração por Inalação , Aerossóis/química , Animais , Varredura Diferencial de Calorimetria/métodos , Preparações de Ação Retardada/química , Dexametasona/sangue , Sistemas de Liberação de Medicamentos/métodos , Inaladores de Pó Seco/métodos , Desenho de Equipamento/métodos , Excipientes/química , Humanos , Ácido Hialurônico/química , Pulmão , Masculino , Microscopia Eletrônica de Varredura/métodos , Modelos Biológicos , Palmitatos/sangue , Tamanho da Partícula , Porosidade , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície , Distribuição Tecidual
5.
J Agric Food Chem ; 65(12): 2609-2614, 2017 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-28276235

RESUMO

Fatty acid esters of monochloropropane 1,2-diol (3-MCPD) are processing-induced toxicants and have been detected in several food categories. This study investigated the absorption, distribution, metabolism, and excretion of 3-MCPD esters in Sprague-Dawley (SD) rats using 3-MCPD 1-monopalmitate as the probe compound. The kinetics of 3-MCPD 1-monopalmitate in plasma was investigated using SD rats, and the results indicated that 3-MCPD 1-monopalmitate was absorbed directly in vivo and metabolized. Its primary metabolites in the liver, kidney, testis, brain, plasma, and urine were tentatively identified and measured at 6, 12, 24, and 48 h after oral administration. Structures were proposed for eight metabolites. 3-MCPD 1-monopalmitate was converted to free 3-MCPD, which formed the phase II metabolites. All of the metabolites were chlorine-related chemical components; most of them existed in urine, reflecting the excretion pattern of 3-MCPD esters. Understanding the metabolism of 3-MCPD esters in vivo is critical for assessing their toxicities.


Assuntos
Palmitatos/farmacocinética , alfa-Cloridrina/farmacocinética , Administração Oral , Animais , Ésteres/administração & dosagem , Ésteres/farmacocinética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Rim/metabolismo , Fígado/metabolismo , Masculino , Palmitatos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Testículo/metabolismo , alfa-Cloridrina/administração & dosagem
6.
An. R. Acad. Farm ; 82(2): 200-209, abr.-jun. 2016. ilus, graf
Artigo em Inglês | IBECS | ID: ibc-154640

RESUMO

Chronic low-grade inflammation in adipose tissue during obesity is associated to an impairment of the insulin signaling cascade. In this study we have evaluated the impact of palmitate or oleate overload of macrophages in triggering lipoapotosis and in the cross-talk with insulin signaling in hepatocytes. Macrophages were stimulated with oleate or palmitate and levels of M1/M2 polarization markers was analyzed. Whereas proinflammatory cytokines were elevated in macrophages stimulated with palmitate, enhanced M2 markers levels was detected in macrophages stimulated with oleate. When hepatocytes were pretreated with conditioned medium from macrophages loaded with palmitate (CM-P) phosphorylation of stress kinases and endoplasmic reticulum (ER) stress signaling was increased, insulin signaling was impaired and lipoapoptosis was detected. Conversely, enhanced insulin receptor (IR)-mediated signaling and reduced levels of the phosphatase protein tyrosine phosphatase 1B (PTP1B) was found in hepatocytes treated with CM from macrophages stimulated with oleate (CM-O). In conclusion, oleate and palmitate elicit an opposite cross-talk between macrophages and hepatocytes. Whereas CM-P interferes at the early steps of insulin signaling, CM-O increases insulin sensitization by decreasing PTP1B. Therefore, targeting PTP1B is a therapeutic strategy to combat hepatic insulin resistance in obesity


La inflamación crónica de bajo grado en el tejido adiposo durante la obesidad se asocia a una disminución de la señalización de la insulina. Hemos evaluado el impacto de la estimulación de los macrófagos con oleato o palmitato y el efecto sobre la lipoapoptosis y la señalización de la insulina en los hepatocitos. Los macrófagos y las células de Kupffer se estimularon con dichos ácidos grasos para analizar los niveles de marcadores de polarización M1/M2. Los macrófagos estimulados con oleato presentaron mayores niveles de marcadores antiinflamatorios, mientras que los tratados con palmitato presentaron una elevada expresión de citoquinas proinflamatorias. Tras el tratamiento de los hepatocitos con medio condicionado de macrófagos estimulados con palmitato (CM-P) detectamos un incremento en la fosforilación de las quinasas de estrés y marcadores de estrés del retículo endoplásmico (ER), junto con un aumento en la lipoapoptosis y un bloqueo en la señalización de la insulina. Por el contrario, en hepatocitos tratados con el medio condicionado de macrófagos estimulados con oleato (CM-O) observamos un aumento en la señalización de la insulina y una reducción en los niveles de la proteína fosfatasa 1B (PTP1B). En conclusión, oleato y palmitato desencadenan respuestas opuestas entre los macrófagos y los hepatocitos. Mientras que el CM-P bloquea las primeras etapas de la señalización de la insulina, el CM-O aumenta la sensibilidad a la insulina disminuyendo la PTP1B. Por tanto, la inhibición de PTP1B es una estrategia terapéutica para combatir la resistencia a la insulina en el hígado en estados de obesidad


Assuntos
Humanos , Síndrome Metabólica/tratamento farmacológico , Obesidade/fisiopatologia , Ácido Oleico/farmacocinética , Palmitatos/farmacocinética , Células de Kupffer/fisiologia , Hepatócitos/fisiologia , Apoptose , Inflamação/fisiopatologia , Mediadores da Inflamação/análise , Anti-Inflamatórios/farmacocinética , Comunicação Parácrina
7.
J. physiol. biochem ; 71(4): 763-772, dic. 2015.
Artigo em Inglês | IBECS | ID: ibc-145728

RESUMO

It has been intensively studied that inflammation contributes to the insulin resistance development in obesity-induced type 2 diabetes mellitus (T2DM). In this study, we assessed the effect of karyopherin Beta1 (KPNBeta1) in hepatic insulin resistance and the underlying mechanisms using high-fat diet (HFD) fed mice and palmitate (PA)-stimulated hepatocytes (HepG2). KPNBeta1 expression is increased in the HFD fed mice liver. PA upregulated KPNBeta1 expression in HepG2 cells in a time-dependent manner. PA also increased pro-inflammatory cytokines expression, including tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), and interleukin 1Beta (IL-1Beta). KPNBeta1 knockdown reversed PA-induced pro-inflammatory cytokines expression and insulin-stimulated glucose uptake in HepG2 cells. In addition, KPNBeta1 knockdown reduced intracellular lipid accumulation. Mechanistically, KPNBeta1 transports nuclear factor kB (NF-kappaB) p65 from the cytoplasm to the nucleus to increase pro-inflammatory genes expression. In summary, KPNBeta1 acts as a positive regulator in the NF-kappaB pathway to enhance palmitate-induced inflammation response and insulin resistance in HepG2 cells


Assuntos
Animais , Ratos , Hepatócitos , Resistência à Insulina/fisiologia , Carioferinas/farmacocinética , Diabetes Mellitus Tipo 2/fisiopatologia , Mediadores da Inflamação/análise , Inflamação/fisiopatologia , NF-kappa B/análise , Obesidade/fisiopatologia , Palmitatos/farmacocinética
8.
J Clin Pharmacol ; 55(1): 93-103, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25043337

RESUMO

RBP-7000 is a long-acting formulation of risperidone designed for once-monthly subcutaneous injection for the treatment of schizophrenia. The objective was to estimate clinically effective doses of RBP-7000 based on model simulations and on the comparison with other long-acting injectable antipsychotics. A population pharmacokinetic model of RBP-7000 was developed in 90 clinically stable schizophrenic patients having received single/repeated doses of 60, 90, or 120 mg. Model simulations were conducted to compare active moiety plasma exposure after repeated RBP-7000 administrations to the published data of long-acting risperidone injection (Risperdal® Consta®) at 25 and 50 mg, and of paliperidone palmitate (Invega® Sustenna®) at 50 and 100 mg equivalent paliperidone. Predictions of dopamine D2 receptor occupancy were derived from the simulated active moiety concentrations. Simulations showed similar active moiety plasma exposure at steady-state for 90 mg of RBP-7000 and 25 mg of long-acting risperidone. In comparison to risperidone, RBP-7000 reached effective concentrations immediately after the first administration. RBP-7000 at the doses of 60 and 90 mg provided similar active moiety plasma concentrations at steady-state compared to 50 and 100 mg equivalent paliperidone, respectively. These findings provide guidance for dose selection in Phase III clinical trials and suggest potential benefits for RBP-7000 over competitors.


Assuntos
Antipsicóticos/farmacocinética , Modelos Biológicos , Adulto , Antipsicóticos/administração & dosagem , Antipsicóticos/sangue , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Feminino , Humanos , Isoxazóis/administração & dosagem , Isoxazóis/sangue , Isoxazóis/farmacocinética , Masculino , Pessoa de Meia-Idade , Palmitato de Paliperidona , Palmitatos/administração & dosagem , Palmitatos/sangue , Palmitatos/farmacocinética , Pirimidinas/sangue , Risperidona/administração & dosagem , Risperidona/sangue , Risperidona/farmacocinética
9.
Circulation ; 130(20): 1790-9, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-25266948

RESUMO

BACKGROUND: Intramyocardial triglyceride (TG) turnover is reduced in pressure-overloaded, failing hearts, limiting the availability of this rich source of long-chain fatty acids for mitochondrial ß-oxidation and nuclear receptor activation. This study explored 2 major dietary fats, palmitate and oleate, in supporting endogenous TG dynamics and peroxisome proliferator-activated receptor-α activation in sham-operated (SHAM) and hypertrophied (transverse aortic constriction [TAC]) rat hearts. METHODS AND RESULTS: Isolated SHAM and TAC hearts were provided media containing carbohydrate with either (13)C-palmitate or (13)C-oleate for dynamic (13)C nuclear magnetic resonance spectroscopy and end point liquid chromatography/mass spectrometry of TG dynamics. With palmitate, TAC hearts contained 48% less TG versus SHAM (P=0.0003), whereas oleate maintained elevated TG in TAC, similar to SHAM. TG turnover in TAC was greatly reduced with palmitate (TAC, 46.7±12.2 nmol/g dry weight per min; SHAM, 84.3±4.9; P=0.0212), as was ß-oxidation of TG. Oleate elevated TG turnover in both TAC (140.4±11.2) and SHAM (143.9±15.6), restoring TG oxidation in TAC. Peroxisome proliferator-activated receptor-α target gene transcripts were reduced by 70% in TAC with palmitate, whereas oleate induced normal transcript levels. Additionally, mRNA levels for peroxisome proliferator-activated receptor-γ-coactivator-1α and peroxisome proliferator-activated receptor-γ-coactivator-1ß in TAC hearts were maintained by oleate. With these metabolic effects, oleate also supported a 25% improvement in contractility over palmitate with TAC (P=0.0202). CONCLUSIONS: The findings link reduced intracellular lipid storage dynamics to impaired peroxisome proliferator-activated receptor-α signaling and contractility in diseased hearts, consistent with a rate-dependent lipolytic activation of peroxisome proliferator-activated receptor-α. In decompensated hearts, oleate may serve as a beneficial energy substrate versus palmitate by upregulating TG dynamics and nuclear receptor signaling.


Assuntos
Gorduras na Dieta/farmacologia , Insuficiência Cardíaca/metabolismo , Miocárdio/metabolismo , Ácido Oleico/farmacologia , PPAR alfa/fisiologia , Palmitatos/farmacologia , Triglicerídeos/metabolismo , Animais , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/metabolismo , Núcleo Celular/metabolismo , Ceramidas/análise , Ciclo do Ácido Cítrico , Gorduras na Dieta/farmacocinética , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Insuficiência Cardíaca/dietoterapia , Insuficiência Cardíaca/etiologia , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/metabolismo , Lipólise , Masculino , Mitocôndrias Cardíacas/metabolismo , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Ressonância Magnética Nuclear Biomolecular , Ácido Oleico/administração & dosagem , Ácido Oleico/farmacocinética , Oxirredução , Palmitatos/administração & dosagem , Palmitatos/farmacocinética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transcrição Gênica
10.
J Clin Endocrinol Metab ; 99(9): E1666-70, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24878055

RESUMO

CONTEXT: The mechanism(s) responsible for diurnal variations in insulin sensitivity of glucose metabolism in healthy people are unclear. OBJECTIVE: The objective of the study was to evaluate whether diurnal variations in whole-body and cellular fatty acid metabolism could contribute to evening insulin resistance in metabolically normal people. SUBJECTS AND DESIGN: We measured plasma the free fatty acid (FFA) concentration, palmitate kinetics, and skeletal muscle expression of genes involved in fatty acid metabolism at breakfast (7:00 am) and dinner (7:00 pm) in 13 overweight (body mass index 27.8 ± 1.2 kg/m(2)) but metabolically normal, women. RESULTS: Plasma FFA concentration was approximately 30% greater just before consuming dinner than breakfast (P < .05) and remained greater after dinner than breakfast (FFA areas under the curve: 0.88 ± 0.33 and 0.51 ± 0.09 µmol/mL × 4 h, P = .001). However, adipose tissue lipolytic activity was not different in the evening and in the morning. Skeletal muscle expression of genes that regulate fatty acid oxidation were 38-82% lower, whereas genes involved in de novo lipogenesis were 51%-87 % higher before dinner than before breakfast (all P < .05), and these changes were associated with diurnal variation in the muscle expression of core clock genes that regulate fatty acid metabolism. CONCLUSION: Metabolically normal women demonstrate diurnal variations in fatty acid metabolism, manifested by an increase in circulating FFAs, presumably derived from previous meal consumption rather than lipolysis of adipose tissue triglycerides, and a shift in muscle fatty acid metabolism from oxidation to lipogenesis. These metabolic alterations could be responsible for the known evening decline in insulin sensitivity.


Assuntos
Glicemia/metabolismo , Ritmo Circadiano/fisiologia , Ácidos Graxos não Esterificados/metabolismo , Resistência à Insulina/fisiologia , Sobrepeso/metabolismo , Tecido Adiposo/metabolismo , Adulto , Ingestão de Alimentos/fisiologia , Feminino , Humanos , Hidrocortisona/sangue , Insulina/sangue , Lipogênese/fisiologia , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Palmitatos/farmacocinética , Valores de Referência
11.
Int J Pharm ; 472(1-2): 380-5, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-24882037

RESUMO

The main purpose of this study was to develop and compare the pharmacokinetic behavior of two paliperidone palmitate (PP) nanosuspensions with different particle size after intramuscular (i.m.) administration. PP nanosuspensions were prepared by wet media milling method and the mean particle size of nanosuspension was controlled as 1,041 ± 6 nm (A) and 505 ± 9 nm (B), respectively. The morphology of nanosuspensions was observed by scanning electron microscope (SEM). Differential scanning calorimeter (DSC) and powder X-ray diffraction (PXRD) confirmed the crystallinity of PP in nanosuspensions. The physical and chemical stabilities of nanosuspensions A and B were investigated by particle analyzer and HPLC after storage for 2 months at 25°C, 4°C and mechanical shaking condition. No obvious change in particle size and chemical degradation of drug were observed. Following single-dose i.m. administration to beagle dogs, the release of paliperidone lasted for nearly 1 month. The Tmax of nanosuspensions A and B was 6 (d) and 10 (d). The AUC0-t and Cmax of nanosuspensions A was 2.0-fold and 1.8-fold higher than nanosuspensions B (p<0.05). The results demonstrated that PP nanosuspensions formulation had long-acting effect. Nanosuspension A with a larger particle size performed better than nanosuspension B. As a result, it is important to design appropriate particle size of nanosuspensions for i.m. administration in order to produce larger therapeutic effect.


Assuntos
Isoxazóis/farmacocinética , Nanopartículas , Palmitatos/farmacocinética , Animais , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada , Cães , Injeções Intramusculares , Isoxazóis/administração & dosagem , Isoxazóis/sangue , Isoxazóis/química , Masculino , Microscopia Eletrônica de Varredura , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanopartículas/ultraestrutura , Palmitato de Paliperidona , Palmitatos/administração & dosagem , Palmitatos/sangue , Palmitatos/química , Tamanho da Partícula , Solubilidade , Suspensões , Difração de Raios X
12.
J Pharm Sci ; 103(7): 2072-2087, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24845884

RESUMO

The present study aims at elucidating the intricate nature of the drug release and absorption following intramuscular (i.m.) injection of sustained-release prodrug nanocrystals/microcrystals. A paliperidone palmitate (PPP) long-acting suspension was characterized with regard to particle size (Dv,50 = 1.09 µm) and morphology prior to i.m. injection in rats. The local disposition was rigorously investigated by means of (immuno)histochemistry and transmission electron microscopy while the concurrent multiphasic pharmacokinetics was linked to the microanatomy. A transient (24 h) trauma-induced inflammation promptly evolved into a subclinical but chronic granulomatous inflammatory reaction initiated by the presence of solid material. The dense inflammatory envelope (CD68(+) macrophages) led to particle agglomeration with subsequent drop in dissolution rate beyond 24 h postinjection. This was associated with a decrease in apparent paliperidone (PP) absorption (near-zero order) until 96 h and a delayed time of occurrence of observed maximum drug plasma concentration (168 h). The infiltrating macrophages phagocytosed large fractions of the depot, thereby influencing the (pro)drug release. Radial angiogenesis (CD31(+)) was observed throughout the inflammatory rim from 72 h onwards and presumably contributed to the sustained systemic PP concentrations by maintaining a sufficient absorptive capacity. No solid-state transitions of the retrieved formulation were recorded with X-ray diffraction analysis. In summary, the initial formulation-driven prodrug (PPP) dissolution and drug (PP) absorption were followed by a complex phase determined by the relative contribution of formulation factors and dynamic physiological variables.


Assuntos
Inflamação , Isoxazóis/farmacocinética , Modelos Biológicos , Músculo Esquelético , Palmitatos/farmacocinética , Pró-Fármacos/farmacocinética , Animais , Preparações de Ação Retardada , Imuno-Histoquímica , Inflamação/metabolismo , Inflamação/patologia , Injeções Intramusculares , Isoxazóis/administração & dosagem , Isoxazóis/química , Masculino , Microscopia Eletrônica de Transmissão , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Nanopartículas , Palmitato de Paliperidona , Palmitatos/administração & dosagem , Palmitatos/química , Tamanho da Partícula , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Ratos Wistar , Propriedades de Superfície , Suspensões , Distribuição Tecidual
13.
Hum Psychopharmacol ; 29(2): 203-10, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24590546

RESUMO

OBJECTIVE: The objective of this study was to characterize the pharmacokinetics of 25, 100, and 150 mg equivalents (eq.) of paliperidone long-acting injection in Chinese subjects with schizophrenia. METHODS: This was an open-label, randomized, parallel group, multicenter study. A total of 48 patients were randomized in a 1:1:1 ratio to one of three groups. Sequential blood samples were collected immediately before injection on day 1 and up to 210 days after the first injection. The plasma paliperidone concentrations were determined by a validated high-performance liquid chromatography/tandem mass spectrometry method. RESULTS: A total of 47 patients received at least one injection of the study medication, and 43 completed the study. The pharmacokinetic (PK) parameters, such as time to maximum concentration, t1/2, and CL/F, were comparable across the three treatment groups (p = 0.935, 0.349, and 0.794, respectively). The differences in maximum plasma concentration, AUC (035 days), AUC (0-210 days), and AUC (0-∞) were significant (p < 0.001) and dose proportional. The inter-individual variation of PK parameters was large. The most frequent treatment-emergent adverse events were prolactin level increasing, injection site pain, tremor, dry mouth, and constipation. CONCLUSIONS: The pharmacokinetics of paliperidone palmitate are linear with respect to time in Chinese subjects with schizophrenia at injections from 25 to 150 mg eq.


Assuntos
Antipsicóticos/efeitos adversos , Antipsicóticos/farmacocinética , Isoxazóis/efeitos adversos , Isoxazóis/farmacocinética , Palmitatos/efeitos adversos , Palmitatos/farmacocinética , Esquizofrenia/tratamento farmacológico , Antipsicóticos/uso terapêutico , Povo Asiático , Cromatografia Líquida de Alta Pressão , Constipação Intestinal/induzido quimicamente , Relação Dose-Resposta a Droga , Feminino , Humanos , Injeções Intramusculares/efeitos adversos , Isoxazóis/uso terapêutico , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Palmitato de Paliperidona , Palmitatos/uso terapêutico , Prolactina/sangue , Esquizofrenia/sangue , Espectrometria de Massas em Tandem , Fatores de Tempo , Resultado do Tratamento , Tremor/induzido quimicamente
14.
Arch Toxicol ; 87(9): 1649-59, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23649841

RESUMO

In order to quantify the relative bioavailability of glycidol from glycidyl fatty acid esters in vivo, glycidyl palmitoyl ester and glycidol were orally applied to rats in equimolar doses. The time courses of the amounts of glycidol binding to hemoglobin as well as the excretion of 2,3-dihydroxypropyl mercapturic acids were determined. The results indicate that glycidol is released from the glycidyl ester by hydrolysis and rapidly distributed in the organism. In relation to glycidol, there was only a small timely delay in the binding to hemoglobin for the glycidol moiety released from the ester which may be certainly attributed to enzymatic hydrolysis. In both cases, however, an analogous plateau was observed representing similar amounts of hemoglobin binding. With regard to the urinary excretion of mercapturic acids, also similar amounts of dihydroxypropyl mercapturic acids could be detected. In an ADME test using a virtual double tag (³H, ¹4C) of glycidyl palmitoyl ester, a diverging isotope distribution was detected. The kinetics of the ¹4C-activity reflected the kinetics of free glycidol released after hydrolysis of the palmitoyl ester. In view of this experimental data obtained in rats, it is at present justified for the purpose of risk assessment to assume complete hydrolysis of the glycidyl ester in the gastrointestinal tract. Therefore, assessment of human exposure to glycidyl fatty acid ester should be regarded as an exposure to the same molar quantity of glycidol.


Assuntos
Compostos de Epóxi/farmacocinética , Palmitatos/farmacocinética , Ácidos Palmíticos/farmacocinética , Propanóis/farmacocinética , Acetilcisteína/análogos & derivados , Acetilcisteína/urina , Administração Oral , Animais , Disponibilidade Biológica , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores/urina , Biotransformação , Radioisótopos de Carbono , Compostos de Epóxi/administração & dosagem , Compostos de Epóxi/sangue , Compostos de Epóxi/metabolismo , Contaminação de Alimentos , Hemoglobinas/metabolismo , Hidrólise , Masculino , Palmitatos/sangue , Ácidos Palmíticos/administração & dosagem , Ácidos Palmíticos/sangue , Ácidos Palmíticos/metabolismo , Propanóis/administração & dosagem , Propanóis/sangue , Propanóis/metabolismo , Ratos , Ratos Wistar , Distribuição Tecidual , Trítio , Valina/análogos & derivados , Valina/sangue
15.
J Psychiatr Res ; 47(5): 579-85, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23421961

RESUMO

Depression is associated with structural and neurochemical changes in limbic structures, including the hippocampus, that control emotion and mood. Structural abnormalities such as decrease in hippocampal cell proliferation, neurogenesis and hippocampal volume, and loss of neurons and glial cells have been widely reported in physical and psychosocial stress paradigms and animal model of depression, but corresponding neurochemical changes are largely unknown. Using neonatal clomipramine (CL)-treated rats as a model to elucidate the association of phospholipase D (PLD) and mammalian target of rapamycin (mTOR) signaling with depressive pathology, we found that the hippocampus of CL-treated rats showed significantly down-regulation of PLD1 expression and attenuation of PLD activity which leads to the less formation of phosphatidic acid (PA), an activator of mTOR, and free choline, a potential biomarker for depression. With lower PA levels which could affect mTOR signaling, we further observed that the phosphorylation of p70S6 kinase, one of the downstream effectors of mTOR, was also significantly decreased in the hippocampus of CL-treated rats compared to the controls. Down-regulation of PLD1 expression, PLD activity and p70S6 phosphorylation was also found in the hypothalamus and frontal cortex with CL-treated rats. Our results indicate that PLD-mTOR signaling is associated with depressive disorder.


Assuntos
Encéfalo/metabolismo , Depressão/patologia , Fosfolipase D/metabolismo , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Animais Recém-Nascidos , Antidepressivos Tricíclicos , Encéfalo/efeitos dos fármacos , Colina/farmacocinética , Clomipramina/toxicidade , Depressão/induzido quimicamente , Depressão/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Masculino , Palmitatos/farmacocinética , Ratos , Ratos Long-Evans , Inibidores Seletivos de Recaptação de Serotonina/toxicidade , Comportamento Sexual Animal/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Trítio/farmacocinética
16.
J Drug Target ; 21(4): 341-53, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23311747

RESUMO

BACKGROUND: Tetramethylpyrazine (TMP) is used to treat cerebrovascular and cardiovascular diseases. However, it displays a short half-life that restricts clinical applications. 2-Hydroxymethyl-3,5,6-trimethylpyrazine (HTMP) is the principal active metabolite of TMP, with similar activity of TMP. Therefore, it makes sense to improve the biopharmaceutical characteristics via HTMP bypassing TMP. PURPOSE: To prolong the half-life of HTMP and achieve improved bioavailability and efficacy compared to commercially available product of tetramethylpyrazine phosphate injection (TMPP-I). METHODS: A lipophilic prodrug of HTMP, palmitate of HTMP (HTMPP) was synthesized, and then the lipid emulsion of HTMPP was developed. The middle cerebral artery occlusion (MCAO) model was applied to evaluate the efficacy in different administration group. RESULTS AND DISCUSSION: The optimized formulation consisted of 1.5% (w/v) HTMPP, 15% (w/v) soybean oil, 1.2% (w/v) soybean lecithin and 0.3% (w/v) poloxamer 188. The AUC0-180 min and the half-life of HTMP in HTMPP-LE was 2.05-fold and 1.48-fold greater than that in TMPP-I. The brain AUC0-120 min of HTMP in HTMPP-LE group increased by 145.6% compared to that in TMPP-I group. These differences could be primarily attributed to dissimilar metabolism between HTMPP and TMP. Consistently, HTMPP-LE exhibited better efficacy on ischemia/reperfusion model than TMPP-I. CONCLUSION: The developed HTMPP-LE suggests a great therapeutic potential for clinical applications.


Assuntos
Palmitatos/química , Palmitatos/farmacocinética , Pirazinas/química , Pirazinas/farmacocinética , Animais , Área Sob a Curva , Disponibilidade Biológica , Química Farmacêutica/métodos , Emulsões/química , Emulsões/farmacocinética , Emulsões/farmacologia , Meia-Vida , Infarto da Artéria Cerebral Média/tratamento farmacológico , Masculino , Camundongos , Palmitatos/administração & dosagem , Pirazinas/administração & dosagem , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
18.
Clín. investig. arterioscler. (Ed. impr.) ; 24(3): 131-140, mayo-jun. 2012. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-105086

RESUMO

Introducción El consumo de dietas ricas en grasas se relaciona con alteraciones cardíacas caracterizadas por un proceso inflamatorio de baja intensidad mediado por NF-κB. PPARbeta/delta ha sido propuesto como potencial diana terapéutica para paliar el proceso inflamatorio asociado a alteraciones cardiovasculares. Sin embargo, se desconoce la implicación de este receptor en la respuesta inflamatoria inducida por lípidos en el corazón (..) (AU)


Introduction High-fat diet intake is associated with cardiac disorders characterised by a low-grade inflammatory process which involves NF-κB activation. PPARbeta/delta has been proposed as a potential therapeutic target to mitigate the inflammatory process related to cardiovascular disorders. However, the involvement of this receptor in lipid-induced inflammatory response in the heart is not yet known (..) (AU)


Assuntos
Animais , Camundongos , PPAR beta/farmacocinética , Inflamação/fisiopatologia , Mediadores da Inflamação/análise , Lipídeos/efeitos adversos , NF-kappa B/fisiologia , Citocinas , Quimiocinas , Palmitatos/farmacocinética , Camundongos Knockout
19.
BMC Psychiatry ; 12: 26, 2012 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-22455454

RESUMO

BACKGROUND: There are no previous reports of paliperidone palmitate's (PP) long term tolerability or pharmacokinetics of the highest dose in patients with schizophrenia. This study evaluates safety and tolerability, as well as pharmacokinetics, of the highest marketed dose of PP (150 mg eq. [234 mg]) in stable patients with schizophrenia over a 1-year period. METHODS: In this 1-year prospective study, eligible patients (aged 18-65 years; Positive and Negative Syndrome Scale's total score ≤ 70) received an initial deltoid injection of PP 150 mg eq. The second injection one week later and subsequent once-monthly injections were deltoid or gluteal. All injections were to be PP 150 mg eq. Patients willing to participate in intensive pharmacokinetic sampling were classified as Treatment A. Patients unwilling to undergo intensive pharmacokinetic sampling or unable to tolerate the 150 mg eq. dose (consequently receiving flexible doses of 50, 100 or 150 mg eq.) were classified as Treatment B. RESULTS: Of the 212 patients (safety analysis set), 73% were men; 45% white; 20% black; 34% Asians; mean (SD) age 41 (10.2) years, and mean (SD) baseline Positive and Negative Syndrome Scale total score 54.9 (9.03). A total of 53% (n = 113) patients completed the study and 104 received PP 150 mg eq. throughout. Mean (SD) mode dose of PP was 144.8 (19.58) mg eq. The dosing initiation regimen resulted in rapidly achieved and maintained therapeutic paliperidone levels over the study (average concentrations during the dosing interval were 34.7, 40.0, and 47.8 ng/mL after the 2nd, 8th, and 14th injection respectively). Most frequent (≥ 10%) treatment-emergent adverse events were nasopharyngitis (n = 37), insomnia (n = 32), injection-site pain (n = 32), headache (n = 28), and tachycardia (n = 27). Akathisia (n = 19) and tremor (n = 11) were the most common extrapyramidal adverse events. 33 patients had an SAE and 27 discontinued due to treatment-emergent adverse events. No deaths were reported. Mean (SD) weight change from baseline was 2.5 (5.41) kg at endpoint. Patients' psychoses remained stable. CONCLUSIONS: Safety results after one-year therapy with the highest available dose of once-monthly paliperidone palmitate were consistent with results from previous studies, with no new concerns noted. Plasma concentrations were within the expected range. TRIAL REGISTRATION NO: ClinicalTrials.gov: NCT01150448.


Assuntos
Antipsicóticos/uso terapêutico , Isoxazóis/uso terapêutico , Palmitatos/uso terapêutico , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico , Adolescente , Adulto , Idoso , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Antipsicóticos/farmacocinética , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Injeções Intramusculares/efeitos adversos , Injeções Intramusculares/estatística & dados numéricos , Isoxazóis/administração & dosagem , Isoxazóis/efeitos adversos , Isoxazóis/farmacocinética , Masculino , Pessoa de Meia-Idade , Palmitato de Paliperidona , Palmitatos/administração & dosagem , Palmitatos/efeitos adversos , Palmitatos/farmacocinética , Estudos Prospectivos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Esquizofrenia/sangue , Falha de Tratamento
20.
Am J Physiol Endocrinol Metab ; 302(11): E1352-62, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22338075

RESUMO

Associations between exponential childhood growth superimposed on low birth weight and adult onset cardiovascular disease with glucose intolerance/type 2 diabetes mellitus exist in epidemiological investigations. To determine the metabolic adaptations that guard against myocardial failure on subsequent exposure to hypoxia, we compared with controls (CON), the effect of intrauterine (IUGR), postnatal (PNGR), and intrauterine and postnatal (IPGR) calorie and growth restriction (n = 6/group) on myocardial macronutrient transporter (fatty acid and glucose) -mediated uptake in pregestational young female adult rat offspring. A higher myocardial FAT/CD36 protein expression in IUGR, PNGR, and IPGR, with higher FATP1 in IUGR, FATP6 in PNGR, FABP-c in PNGR and IPGR, and no change in GLUT4 of all groups was observed. These adaptive macronutrient transporter protein changes were associated with no change in myocardial [(3)H]bromopalmitate accumulation but a diminution in 2-deoxy-[(14)C]glucose uptake. Examination of the sarcolemmal subfraction revealed higher basal concentrations of FAT/CD36 in PNGR and FATP1 and GLUT4 in IUGR, PNGR, and IPGR vs. CON. Exogenous insulin uniformly further enhanced sarcolemmal association of these macronutrient transporter proteins above that of basal, with the exception of insulin resistance of FATP1 and GLUT4 in IUGR and FAT/CD36 in PNGR. The basal sarcolemmal macronutrient transporter adaptations proved protective against subsequent chronic hypoxic exposure (7 days) only in IUGR and PNGR, with notable deterioration in IPGR and CON of the echocardiographic ejection fraction. We conclude that the IUGR and PNGR pregestational adult female offspring displayed a resistance to insulin-induced translocation of FATP1, GLUT4, or FAT/CD36 to the myocardial sarcolemma due to preexistent higher basal concentrations. This basal adaptation of myocardial macronutrient transporters ensured adequate fatty acid uptake, thereby proving protective against chronic hypoxia-induced myocardial compromise.


Assuntos
Proteínas de Transporte/metabolismo , Retardo do Crescimento Fetal/metabolismo , Transtornos do Crescimento/metabolismo , Miocárdio/metabolismo , Adaptação Fisiológica , Análise de Variância , Animais , Animais Recém-Nascidos , Western Blotting , Peso Corporal/fisiologia , Restrição Calórica/efeitos adversos , Cateterismo Cardíaco , Membrana Celular/metabolismo , Desoxiglucose/metabolismo , Ecocardiografia , Feminino , Hormônios/metabolismo , Hipóxia/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Miocárdio/citologia , Tamanho do Órgão/fisiologia , Palmitatos/farmacocinética , Gravidez , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Ratos Sprague-Dawley
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