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1.
Chem Soc Rev ; 51(16): 7260-7280, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35899763

RESUMO

Single atom catalysts (SACs) offer unprecedented opportunities for high-efficiency reactions taking place in many important fields of catalytic processes, electrochemistry, and photoreactions. Due to their maximized atomic utilization and unique electronic and chemical properties, SACs can provide high activity and excellent selectivity for gas adsorption and electron transport, leveraging SACs that enhance the detection sensitivity and selectivity to target gases. In the past few years, SACs including both noble (Pt, Pd, Au, etc.) and non-noble (Mn, Ni, Zn etc.) metals have been demonstrated to be very useful in optimizing sensing performances. However, a comprehensive review on this topic is still missing. Herein, we summarize the synthesis technologies of SACs that are applicable to gas sensors. The electronic and chemical interactions between SACs and host sensing materials, which are crucial to sensor functions, are discussed. Then, we highlight the application progress of various SACs in gas sensors. Prospects in the creation of new sensing materials with emerging SACs and versatile supports are also present. Finally, the challenges and prospects of SACs in the future development of sensors are analyzed.

2.
Int J Mol Sci ; 23(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36077447

RESUMO

Obesity has become an extensive threat to human health due to associated chronic inflammation and metabolic diseases. Apoptosis-associated speck-like protein (ASC) is a critical link between inflammasome and apoptosis-inducing proteins. In this study, we aimed to clarify the role of ASC in lipid metabolism. With high-fat diet (HFD) and knockout leptin gene mice (ob/ob), we found that ASC expression in subcutaneous adipose tissue (SAT) correlated with obesity. It could also positively regulate the reprogramming of cellular energy metabolism. Stromal vascular fractions (SVF) cells derived from the SAT of Asc-/- mice or SVF from wild-type (WT) mice transfected with ASC siRNA were used to further investigate the underlying molecular mechanisms. We found ASC deficiency could lead to lipogenesis and inhibit lipolysis in SAT, aggravating lipid accumulation and impairing metabolic balance. In addition, our results showed that p53 and AMPKα expression were inhibited in SAT when ASC level was low. p53 and AMP-activated protein kinase α (AMPKα) were then assessed to elucidate whether they were downstream of ASC in regulating lipid metabolism. Our results revealed that ASC deficiency could promote lipid accumulation by increasing lipogenesis and decreasing lipolysis through p53/AMPKα axis. Regulation of ASC on lipid metabolism might be a novel therapeutic target for obesity.


Assuntos
Lipogênese , Lipólise , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Humanos , Lipídeos , Lipogênese/genética , Lipólise/fisiologia , Camundongos , Obesidade/metabolismo , Gordura Subcutânea/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
3.
Eur J Neurosci ; 52(11): 4586-4601, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33098156

RESUMO

In the brain, NLRP3 (Nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin-domain-containing 3) inflammasome is mainly expressed in microglia located in the hippocampus and other mood-regulated regions, which are particularly susceptible to stress. The activation of NLRP3 inflammasome and production of the activation products may contribute to the development of depressive disorder and memory deficits. Indoleamine 2, 3-dioxygenase (IDO) is a key factor mediating inflammation and major depressive disorder (MDD). We here generated NLRP3 and apoptosis-associated speck-like protein containing caspase recruitment domain (ASC)-knockout mice, respectively, to verify the effects of NLRP3 or ASC deficiency on lipopolysaccharide (LPS)-induced depressive-like behaviors, neuroinflammation, and regulation of IDO expression. Furthermore, we treated these mice with the antidepressant clomipramine (CLO) to observe its effect on depressive-like behaviors and the expression of the NLRP3 inflammasome and LPS-induced IDO. We found that intraperitoneal LPS administration led to marked depressive-like behavior and neuroinflammation. NLRP3 or ASC deficiency attenuated LPS-induced depressive-like symptoms and increased IDO gene expression, which was accompanied by inhibition of LPS-induced microglial activation, suggesting that IDO may be a downstream mediator of the NLRP3 inflammasome in inflammation-mediated depressive-like behaviors. Clomipramine administration ameliorated depressive-like behavior in LPS-treated mice by regulating the expression of ASC and IDO. In conclusion, NLRP3 inflammasome is involved in LPS-induced depressive-like behaviors, and that NLRP3 and ASC may play roles in regulating IDO expression in microglia. This may be a potential mechanism for its involvement in MDD. The antidepressant effect of clomipramine may be exerted through the regulation of ASC-mediated expression of IDO.


Assuntos
Transtorno Depressivo Maior , Dioxigenases , Animais , Transtorno Depressivo Maior/induzido quimicamente , Transtorno Depressivo Maior/tratamento farmacológico , Hipocampo/metabolismo , Inflamassomos/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos , Microglia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR
4.
Cell Physiol Biochem ; 41(2): 784-794, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28214891

RESUMO

BACKGROUND/AIMS: Activating transcription factor 4 (ATF4) is a member of the activating transcription factor family which regulates the expression of genes involved in amino acid metabolism, redox homeostasis and ER stress responses. ATF4 is also over-expressed in human solid tumors, although its effect on responsiveness to radiation is largely unexplored. METHODS: Real-time PCR was used to detect ATF4 mRNA levels in cells treated with different doses of 60Coγ radiation. Cell viability was assayed using a cell counting kit. The cell cycle was analyzed using flow cytometry, and cell apoptosis was assayed using Annexin V-PI double labeling. Small interfering RNA (siRNA) against ATF4 was transfected into ECV304 cells using Lipofectamine 2000. An ATF4 over-expression plasmid (p-ATF4-CGN) was transfected into HEK293 cells that endogenously expressed low levels of ATF4. The levels of intracellular reactive oxygen species (ROS) were measured using CM-H2DCFDA as a probe. RESULTS: ATF4 mRNA and protein expression levels were higher after radiation and increased in a dose- and time-dependent manner in AHH1 lymphoblast cells (P < 0.05). An increase in ATF4 levels was also observed after radiation in primary murine spleen cells, human endothelial ECV304 cells, human liver LO2 cells, breast cancer MCF7 cells, and human hepatocellular carcinoma HEPG2 cells. No change was observed in human embryonic kidney 293 (HEK293) cells. Over-expressing ATF4 in HEK293 cells inhibited cell proliferation, increased cell apoptosis and significantly increased the proportion of cells in G1 phase. Conversely, when ATF4 expression was knocked down using siRNA in ECV304 cells, it protected the cells from radiation-induced apoptosis. These findings suggest that ATF4 may play a role in radiation-induced cell killing by inhibiting cell proliferation and promoting cell apoptosis. CONCLUSIONS: In this study, we found that radiation up-regulated the expression of ATF4. We used ATF4 knockdown and over-expression systems to show that ATF4 may play a role in radiation-induced cellular apoptosis.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Apoptose/efeitos da radiação , Raios gama , Regulação para Cima/efeitos da radiação , Fator 4 Ativador da Transcrição/antagonistas & inibidores , Fator 4 Ativador da Transcrição/genética , Animais , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Radioisótopos de Cobalto/química , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos da radiação , Células HEK293 , Células Hep G2 , Humanos , Camundongos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo
5.
J Neuroinflammation ; 13(1): 71, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-27048470

RESUMO

BACKGROUND: The NLRP3 inflammasome (NOD-like receptor family, pyrin domain containing 3) is an intracellular protein complex that plays an important role in innate immune sensing. Its activation leads to the maturation of caspase-1 and regulates the cleavage of interleukin (IL)-1ß and IL-18. Various studies have shown that activation of the immune system plays a pivotal role in the development of fatigue. However, the mechanisms underlying the association between immune activation and fatigue remained elusive, and few reports have described the involvement of NLRP3 inflammasome activation in fatigue. METHODS: We established a mouse fatigue model with lipopolysaccharide (LPS, 3 mg/kg) challenge combined with swim stress. Both behavioural and biochemical parameters were measured to illustrate the characteristics of this model. We also assessed NLRP3 inflammasome activation in the mouse diencephalon, which is the brain region that has been suggested to be responsible for fatigue sensation. To further identify the role of NLRP3 inflammasome activation in the pathogenesis of chronic fatigue syndrome (CFS), NLRP3 KO mice were also subjected to LPS treatment and swim stress, and the same parameters were evaluated. RESULTS: Mice challenged with LPS and subjected to the swim stress test showed decreased locomotor activity, decreased fall-off time in a rota-rod test and increased serum levels of IL-1ß and IL-6 compared with untreated mice. Serum levels of lactic acid and malondialdehyde (MDA) were not significantly altered in the treated mice. We demonstrated increased NLRP3 expression, IL-1ß production and caspase-1 activation in the diencephalons of the treated mice. In NLRP3 KO mice, we found remarkably increased locomotor activity with longer fall-off times and decreased serum IL-1ß levels compared with those of wild-type (WT) mice after LPS challenge and the swim stress test. IL-1ß levels in the diencephalon were also significantly decreased in the NLRP3 KO mice. By contrast, IL-6 levels were not significantly altered. CONCLUSIONS: These findings suggest that LPS-induced fatigue is an IL-1ß-dependent process and that the NLRP3/caspase-1 pathway is involved in the mechanisms of LPS-induced fatigue behaviours. NLRP3/caspase-1 inhibition may be a promising therapy for fatigue treatment.


Assuntos
Síndrome de Fadiga Crônica/fisiopatologia , Fadiga/induzido quimicamente , Fadiga/fisiopatologia , Inflamassomos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Fadiga/psicologia , Síndrome de Fadiga Crônica/psicologia , Feminino , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Psicológico/fisiopatologia , Natação/psicologia
6.
Toxicol Appl Pharmacol ; 307: 45-61, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27457977

RESUMO

EPO-018B, a synthetic peptide-based erythropoiesis stimulating agent (ESA), is mainly designed for treatment of anemia caused by chronic renal failure and chemotherapy against cancer. It overcomes the deficiencies of currently approved ESA, including the frequent administration of temperature-sensitive recombinant protein and anti-EPO antibody-mediated pure red cell aplasia (PRCA). This study was designed to evaluate the potential chronic toxicity of EPO-018B. Subcutaneous administration doses were designed as 0, 0.2, 1 and 10mg/kg for six months for 160 rats (20/gender/group) and 0, 0.3, 3 and 20mg/kg for nine months for 32 monkeys (4/gender/group) once every three weeks. The vehicles received the same volume of physiological saline injection. All animals survived to the scheduled necropsies after six weeks (for rats) and fourteen weeks (for monkeys) recovery period, except for the two high-dose female rats and two high-dose male monkeys, which were considered related to the increased RBCs, chronic blood hyperviscosity and chronic cardiac injury. EPO-018B is supposed to be subcutaneously injected once every month and the intended human therapeutic dose is 0.025mg/kg. The study findings at 0.2mg/kg for rats and 0.3mg/kg for monkeys were considered to be the study NOAEL (the no observed adverse effect level), which were more than ten times the intended human therapeutic dose. Higher doses caused adverse effects related to the liver toxicity, cardiotoxicity, appearance of neutralizing antibodies of EPO-018B and the decrease of serum glucose and cholesterol. Most treatment-induced effects were reversible or revealed ongoing recovery upon the discontinuation of treatment. The sequelae occurred in rats and monkeys were considered secondary to exaggerated pharmacology and would less likely occur in the intended patient population. As to the differences between human beings and animals, the safety of EPO-018B need to be further confirmed in the future clinical studies.


Assuntos
Eritropoetina/análogos & derivados , Eritropoetina/toxicidade , Hematínicos/toxicidade , Animais , Anticorpos/sangue , Avaliação Pré-Clínica de Medicamentos , Feminino , Hematínicos/imunologia , Testes Hematológicos , Macaca fascicularis , Masculino , Ratos Sprague-Dawley
7.
Cochrane Database Syst Rev ; (1): CD009782, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26769010

RESUMO

BACKGROUND: Trabeculectomy is performed as a treatment for glaucoma to lower intraocular pressure (IOP). The surgical procedure involves creating a channel through the wall of the eye. However scarring during wound healing can block this channel which will lead to the operation failing. Anti-vascular endothelial growth factor (VEGF) agents have been proposed to slow down healing response and scar formation. OBJECTIVES: To assess the effectiveness of anti-VEGF therapies administered by subconjunctival injection for the outcome of trabeculectomy at 12 months follow-up and to examine the balance of benefit and harms when compared to any other anti-scarring agents or no additional anti-scarring agents. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2015, Issue 10), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to November 2015), EMBASE (January 1980 to November 2015), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 12 November 2015. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of anti-VEGF therapies administered by subconjunctival injection compared to any other anti-scarring agents or no additional anti-scarring agents (no treatment or placebo) in trabeculectomy surgery. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Our primary outcome was successful trabeculectomy at 12 months after surgery which was defined as achieving a target IOP (usually no more than 21 mm Hg) without any additional intervention. Other outcomes included: qualified success (achieving target IOP with or without additional intervention), mean IOP and adverse events. MAIN RESULTS: We included five RCTs (175 participants, 177 eyes) that met the inclusion criteria in this review.One trial conducted in Iran (37 participants, 37 eyes) compared anti-VEGF (bevacizumab 0.2 mg) versus control (sham injection) in people with refractory glaucoma. We judged this study to be at low risk of bias.The primary outcome of this review was not reported; mean IOP at three months was 15.1 mm Hg (standard deviation 1.0) in both anti-VEGF and control groups.Four trials compared anti-VEGF to mitomycin C (MMC) (138 particpants, 140 eyes). These studies were conducted in India, Iran, Turkey and the USA. The anti-VEGF agent used in these four trials was bevacizumab 2.5 mg (two trials), bevacizumab 1.25 mg three times and ranibizumab 0.5 mg. Two trials were at high risk of bias in two domains and one trial was at high risk of bias in four domains.Only one of these trials reported the primary outcome of this review (42 participants, 42 eyes). Low quality evidence from this trial showed that people receiving bevacizumab 2.5 mg during primary trabeculectomy were less likely to achieve complete success at 12 months compared to people receiving MMC but the confidence interval (CI) was wide and compatible with increased chance of complete success for anti-VEGF (risk ratio (RR) 0.71, 95% CI 0.46 to 1.08), Assuming that approximately 81% of people receiving MMC achieve complete success, the anticipated success using anti-VEGF agents would be between 37.2% and 87.4%. The same trial suggested no evidence for any difference in qualified success between bevacizumab and MMC (RR 1.00, 95% CI 0.87 to 1.14, moderate quality evidence). Two trials of primary trabeculectomy provided data on mean IOP at 12 months; one trial of bevacizumab 2.5 mg and one trial of ranibizumab 0.5 mg. Mean IOP was 1.86 mm Hg higher (95% CI 0.15 to 3.57) in the anti-VEGF groups compared to the MMC groups (66 people, low quality evidence). Data were reported on wound leak, hypotony, shallow anterior chamber and endophthalmitis, but these events occurred rarely and currently there are not enough data available to detect any differences, if any, between the two treatments. AUTHORS' CONCLUSIONS: The evidence is currently of low quality which is insufficient to refute or support anti-VEGF subconjunctival injection for control of wound healing in glaucoma surgery. The effect on IOP control of anti-VEGF agents in glaucoma patients undergoing trabeculectomy is still uncertain, compared to MMC.Further RCTs of anti-VEGF subconjunctival injection in glaucoma surgery are required, particularly compared to sham treatment with at least 12 months follow-up.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Glaucoma/cirurgia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Cicatrização/efeitos dos fármacos , Bevacizumab/uso terapêutico , Cicatriz/prevenção & controle , Humanos , Pressão Intraocular , Mitomicina/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Ranibizumab/uso terapêutico , Trabeculectomia/efeitos adversos
8.
Regul Toxicol Pharmacol ; 70(1): 379-91, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25108057

RESUMO

Serotonin 5-hydroxytryptamine 4(5-HT4) receptor agonists have been widely prescribed as a prokinetics drug for patients with gastro-esophageal reflux disease and functional dyspepsia. QX100626, one of the 5-HT4 receptor agonists, has been studied as a promising agent for this clinical use. The objective of the present study was to identify possible target organs of toxicity and propose a non-toxic dose of QX100626 for clinical usage. After single lethal dose oral and intravenous testing in rodents, some signs indicative of adverse CNS effects were observed. The minimum toxic dose of QX100626 for a single oral administration for dogs was 90.0mg/kgb.w., and the severe toxic dose was more than 300mg/kgb.w. The No Observed Adverse Effect Level (NOAEL) of QX100626 by daily oral administration for rats and dogs was 20mg/kg and 10mg/kg, respectively, whereas the minimum toxic dosages were 67 and 30mg/kg, respectively. All of the adverse effects suggested that kidney, digestive tract, as well as nervous, hematological, and respiratory systems might be the target organs of toxicity for humans induced by QX100626. The compound could be a safe alternative to other existing prokinetic agents for the treatment of functional bowel disorders.


Assuntos
Fármacos Gastrointestinais/toxicidade , Agonistas do Receptor 5-HT4 de Serotonina/toxicidade , Administração Intravenosa , Administração Oral , Animais , Cães , Relação Dose-Resposta a Droga , Feminino , Fármacos Gastrointestinais/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nível de Efeito Adverso não Observado , Ratos , Ratos Sprague-Dawley , Agonistas do Receptor 5-HT4 de Serotonina/administração & dosagem , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica
9.
Regul Toxicol Pharmacol ; 69(3): 558-71, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24928566

RESUMO

CMS-1, mainly composed of imperatorin as its active compound, is a partially purified fraction of a Chinese herbal medicine, Semen Cnidium monnieri. CMS-1 has the potential to be further developed as a new treatment for hypertension. Thus, we studied its toxicity in both Sprague-Dawley rats and beagle dogs. Rats (0-900mg/kg/day) and dogs (0-450mg/kg/day) received CMS-1 orally for 30 consecutive days, followed by a 15-day recovery period. The major target organs of CMS-1 toxicity are the GI (inappetence), liver (hepatocellular necrosis, enzyme elevation), thymus (atrophy), cardiovascular (hypotension), changes in ECG T and P waveforms, elevation of nitrous oxide levels and hematological (RBC parameters disturbances) systems. Most treatment-induced adverse effects were reversible or showed a progressive recovery upon discontinuation of the treatment. The No Observed Adverse Effect Level (NOAEL) was 100mg/kg/day for rats and 50mg/kg/day for dogs. This non-clinical study suggests that clinical monitoring of CMS-1 in patients should focus on the gastrointestinal system, blood tests for liver functions, electrolytes, and blood homeostasis, cardiovascular functions, and immune functions.


Assuntos
Anti-Hipertensivos/efeitos adversos , Cnidium/efeitos adversos , Plantas Medicinais/efeitos adversos , Animais , Cães , Feminino , Testes Hematológicos/métodos , Masculino , Óxido Nitroso/metabolismo , Nível de Efeito Adverso não Observado , Órgãos em Risco , Ratos , Ratos Sprague-Dawley , Segurança
10.
Regul Toxicol Pharmacol ; 64(3): 361-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23000416

RESUMO

The recombinant soluble human TRAIL mutant (DATR), derived from tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), is a promising agent for cancer therapy. The present study evaluated the synergetic toxicity of DATR in combination with traditional chemotherapeutics, including irinotecan, polyene paclitaxel and oxaliplatin in rats. Rats treated with polyene paclitaxel alone or in combination with DATR showed severe diarrhea, appetite inhibition, increasing sodium (Na(+)), potassium (Cl(-)) and glucose (GLU) and serious disorders in the haematological system. Increasing total bilirubin (TBIL) and blood urea nitrogen (BUN) were detected in the rats treated with oxaliplatin alone or in combination with DATR. Furthermore, except that the BUN and Crea of male rats treated with irinotecan in combination with DATR were higher than those of treated with irinotecan, the addition of DATR does not increase the toxicity induced by irinotecan, polyene paclitaxel and oxaliplatin. In conclusion, DATR probably increases kidney lesions of rat with irinotecan, but does not increase the toxicity induced by polyene paclitaxel and oxaliplatin. This indicated that DATR has promising potential in clinical combination therapies. Furthermore, the toxicity induced by DATR on the liver, kidneys and haematological system should be considered carefully if DATR is used in combination with traditional chemotherapeutics.


Assuntos
Camptotecina/análogos & derivados , Compostos Organoplatínicos/toxicidade , Paclitaxel/toxicidade , Ligante Indutor de Apoptose Relacionado a TNF/toxicidade , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Nitrogênio da Ureia Sanguínea , Camptotecina/administração & dosagem , Camptotecina/toxicidade , Feminino , Doenças Hematológicas/induzido quimicamente , Doenças Hematológicas/patologia , Humanos , Irinotecano , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Paclitaxel/administração & dosagem , Paclitaxel/química , Polienos/química , Ratos , Ratos Sprague-Dawley , Ligante Indutor de Apoptose Relacionado a TNF/administração & dosagem
11.
Regul Toxicol Pharmacol ; 61(2): 230-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21856364

RESUMO

The recombinant soluble human TRAIL mutant (DATR), derived from tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), is a promising agent for cancer therapy. The present study evaluated the toxicity of DATR in rats and monkeys. Based on the results, the safety and toxic doses of DATR intravenously injected to rats for 50 days were 60 and 180 mg/kg, respectively, and when delivered intravenously guttae to monkeys for 50 days, these levels were 10 and 30 mg/kg, respectively. The main toxic effects in rats were red blood cell count and haemoglobin decreases; blood urea nitrogen and creatinine increases. The main toxic effects in monkeys included red blood cell count and haemoglobin decreases; alanine aminotransferase and aspartate aminotransferase increases; high proliferation of karyocytes of the erythrocyte series; and regional hydropic degeneration of hepatic parenchymal cells. The TUNEL assay showed both 90 mg/kg DATR- and TRAIL-induced apoptosis of the liver in monkeys, which confirmed the hepatotoxicity of DATR. These findings indicated that the target toxic organs of DATR might be the haematological system. Furthermore, kidney in rats and liver in monkeys are also likely target toxic organs. The toxicity was reversible and did not differ from that associated with TRAIL administered at the same dosage.


Assuntos
Ligante Indutor de Apoptose Relacionado a TNF/toxicidade , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Macaca fascicularis , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/toxicidade
12.
Acta Pharmacol Sin ; 31(8): 938-43, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20686519

RESUMO

AIM: To reinvestigate the characteristics of reserpine-induced gastric mucosal lesions (GMLs). METHODS: The GML-inducing effect of reserpine and the time-course of recovery from reserpine-induced GMLs were examined in Sprague-Dawley (SD) rats. The GML-inducing and blood pressure-decreasing effects of Compound Hypotensive Tablets (CHTs) were investigated in spontaneously hypertensive rats (SHRs). Intracerebroventricular (icv) injection and vagotomy were performed to verify the central vagal mechanism in reserpine-induced GMLs. RESULTS: Single intraperitoneal (ip) injections of reserpine (0.25, 0.5, 1, 2, 4, and 6 mg/kg) dose-dependently induced GMLs in SD rats. Both single and repeated (2 weeks) oral administrations of reserpine led to slight GMLs at doses of 24 mg/kg and 10 mg/kg, respectively. Blood pressure was significantly decreased in SHRs after 2 months of CHT administration (0.01 and 0.03 mg/kg; doses were expressed as the amount of reserpine in the CHT). CHT doses of 0.3 mg/kg induced GMLs, but 0.1 mg/kg did not. Examining the time course of recovery from GMLs, severe GMLs occurred 18 h after ip reserpine (4 mg/kg), obviously lessened at 1 week and healed spontaneously at 3 weeks. Intracerebroventricular injections of reserpine caused GMLs at much lower doses (0.08 and 0.4 mg/kg), and reserpine-induced GMLs were greatly inhibited by vagotomy, suggesting the involvement of a central vagal mechanism. CONCLUSION: Reserpine-induced GMLs were dose-dependent, and the lesions healed spontaneously within 3 weeks. Long-term treatment with CHT at doses adequate to decrease blood pressure will not induce GMLs. A central vagal mechanism was involved in reserpine-induced GMLs.


Assuntos
Anti-Hipertensivos/toxicidade , Mucosa Gástrica/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Reserpina/toxicidade , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Esquema de Medicação , Mucosa Gástrica/patologia , Hipertensão/fisiopatologia , Injeções Intraperitoneais , Injeções Intraventriculares , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Reserpina/administração & dosagem , Reserpina/farmacologia , Fatores de Tempo
13.
Regul Toxicol Pharmacol ; 56(2): 148-55, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19766684

RESUMO

Safety evaluation of synthetic human brain natriuretic peptide (shBNP) was carried out in cynomolgus monkeys (Macaca fascicularis) by 2-week intravenous toxicity studies. System exposure was also assessed throughout the whole administration. Three test groups received doses of 432, 1440 and 4320 microg/kg/day of shBNP, with a high infusion rate of 36 mL/kg/hr for 30 min compared to the clinical protocol of continuous infusion over 24h. Commercially available recombinant human brain natriuretic peptide (rhBNP) of 1440 microg/kg/day was used as positive control. The 2-week repeated intravenous doses of shBNP resulted in reversible increased serum LDH and CPK in monkeys receiving 1440 and 4320 microg/kg/day dose with no pertinent histopathological changes. Some changes related to the pharmacologic effects of BNP including hypotension was observed after administration. No treatment-related mortalities or renal dysfunction were found. Controversy about the safety issue of BNP as an exogenous hormone concerning ventricular remodeling and myocardial cell apoptosis, coupled with our results, were also discussed. The no-observed-adverse-effect level (NOAEL) was considered to be 432 microg/kg /day, which is about 20 times higher than the commonly used clinical dose. The results of the present study advocate the safety of shBNP in cynomolgus monkeys at levels used in the study.


Assuntos
Peptídeo Natriurético Encefálico/sangue , Peptídeo Natriurético Encefálico/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Humanos , Infusões Intravenosas , Macaca fascicularis , Masculino , Peptídeo Natriurético Encefálico/administração & dosagem , Nível de Efeito Adverso não Observado , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/sangue , Proteínas Recombinantes/toxicidade , Medição de Risco , Fatores de Tempo
14.
Stroke ; 40(12): 3876-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19892999

RESUMO

BACKGROUND AND PURPOSE: Angiotensin receptor blockers are widely used in patients at high risk of cardiocerebrovascular events. The aim of this meta-analysis was to investigate the effects of angiotensin receptor blockers on the risk of stroke. METHODS: Electronic searches of MEDLINE, EMBASE, and the Cochrane central register of controlled trials were performed. A total of 20 randomized clinical trials with 108 286 patients reporting stroke were available for this clinical outcome analysis. RESULTS: Angiotensin receptor blockers were associated with a significant reduction in the risk of stroke than placebo with an OR of 0.91 (0.84 to 0.98). Angiotensin receptor blockers were associated with no significant reduction in the risk of stroke compared with angiotensin-converting enzyme inhibitors (OR, 0.93; 0.84 to 1.03) and calcium antagonists (OR, 1.16; 0.91 to 1.48). CONCLUSIONS: Evidence of the benefit of angiotensin receptor blockers on the risk of stroke is provided when compared with placebo. There was no evidence of the benefit when comparing angiotensin receptor blockers with angiotensin-converting enzyme inhibitors and with calcium antagonists.


Assuntos
Angiotensina II/antagonistas & inibidores , Angiotensina II/fisiologia , Antagonistas de Receptores de Angiotensina , Receptores de Angiotensina/fisiologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Hipertensão/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Fatores de Risco , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento
15.
Environ Toxicol Pharmacol ; 27(2): 237-46, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21783946

RESUMO

MCC-555, a treatment candidate for type 2 diabetes, is a novel thiazolidinedione which has comparatively high anti-diabetic efficacy. The present study was conducted to evaluate its toxicity and toxicokinetics in beagle dogs by oral administration at doses of 0, 6.67, 20 or 40mg/kg/day for 270 days. A 30-day recovery period was included at the end of the study to evaluate the reversibility of the toxic effects. During the treatment and recovery periods, the effects of the test agent on mortality, body weight, food consumption, hematology, serum biochemistry, urinalysis, electrocardiogram (ECG), organ weights, bone marrow and histopathology were examined. There were no treatment-related mortalities. Vomiting was observed in dogs receiving 40mg/kg/day during administration, but the dogs recovered within 1h after oral administration. Significant increases in total bilirubin and alkaline phosphatase were observed in dogs receiving the 40mg/kg/day dose during the treatment period, but the levels returned toward normal during the 30-day recovery period. Mild hydropic or fatty degeneration in the liver and inflammatory cell infiltration in the hepatic lobule or portal area was also observed sporadically without a dose-dependent relationship at the end of treatment and recovery periods. The most apparent toxicity in dogs was in the digestive system. However, these toxic effects of MCC-555 were transient and reversible. The accumulation of MCC-555 after 270-day oral administration was not notable at the toxic dose of 40mg/kg/day and the no-observed-adverse-effect level (NOAEL) was 20mg/kg/day. No differences in toxicokinetics of MCC-555 were observed between male and female dogs and no significant accumulation of MCC-555 was observed in tissues after 270 days of repeated treatments. MCC-555 distribution into different organs showed a higher penetration in the liver, kidneys and testes, followed by the ovaries and uterus. Metabolites and the metabolic style of MCC-555 are to be approved.

16.
Am J Hypertens ; 21(5): 546-52, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18437146

RESUMO

BACKGROUND: Hypertension is a major risk factor for cardiovascular disease, and data regarding the efficacy and tolerability of telmisartan compared with losartan on blood pressure (BP) control in patients with hypertension. METHODS: Pertinent studies were selected through extensive searches of PubMed (1966 to 29 December 2007), Embase (1980 to 29 December 2007), and the Cochrane library (29 December 2007). Randomized clinical trials comparing telmisartan with losartan in patients with hypertension were selected using predefined criteria. The main efficacy measures were reduction in diastolic and systolic BP (DBP and SBP), and therapeutic response of DBP and SBP. The pooled estimates were carried out using RevMan version 4.2 software. RESULTS: Eleven studies involving 1,832 patients were included in the analysis. Ten trials with 1,792 patients reported reduction in clinic BP; six trials with 1,163 patients reported ambulatory BP reduction; seven trials with 1,675 patients reported therapeutic response of BP. Funnel plots indicated that one trial had true heterogeneity. Use of telmisartan resulted in a significant reduction in clinic DBP (weighted mean difference 1.52, 95% confidence interval (CI) 0.85-2.19) and SBP (2.77, 1.90-3.63) when compared with losartan. There was also a significant reduction in 24-h mean ambulatory DBP (2.49, 0.56-4.42) and SBP (2.47, 0.40-4.55) with telmisartan as compared to losartan. There was also a significant increase in therapeutic response of DBP (relative risk (RR) 1.14, 1.04-1.23) and SBP response (1.10, 1.01-1.20) with telmisartan as compared to losartan. Both telmisartan and losartan were well tolerated. CONCLUSIONS: In comparison with losartan, telmisartan provides superior control of BP and has no association with increased risk of adverse events.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Losartan/uso terapêutico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Benzimidazóis/efeitos adversos , Benzoatos/efeitos adversos , Feminino , Humanos , Hipertensão/fisiopatologia , Losartan/efeitos adversos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Telmisartan , Resultado do Tratamento
17.
Food Chem Toxicol ; 46(2): 575-80, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17942207

RESUMO

Sinafloxacin is a new quinolone antibacterial agent. The present study was conducted to determine its toxicity at low flow rate intravenous infusion doses of 0, 10, 30, and 60 mg/kg/day in rats and at 0, 25, 50, and 100mg/kg/day in dogs 6 days per week for 60 days. A 20-day recovery period was included at the end of the study to evaluate the reversibility of the toxic effects. During the treatment and recovery periods, the effects of the test agent on mortality, body weight, food consumption, hematology, serum biochemistry, urinalysis, electrocardiogram (ECG), organ weights, bone marrow, and histopathology were examined. There were no treatment-related mortalities. Dysphoria and local irritation were observed in rats during administration, but the rats recovered soon after administration. Dysphoria, dermal rubeosis, salivation, vomiting and local irritation were observed in dogs receiving 50 or 100mg/kg/day during administration, but all dogs also recovered within 30 min after infusion. Significant increases in total bilirubin and glucose, and a significant decrease in total protein were observed in rats receiving the 60 mg/kg/day dose at the end of treatment period, but the levels returned toward normal during the 20-day recovery period. The most apparent toxicity was the digestive system of both rats and dogs, with irritation also occurring in the vein used for infusion. There were also notable effects on the endocrine system in rats and the central nervous system (CNS) in dogs. However, these toxic effects of sinafloxacin were transient and were reversible. The no-observed adverse effect level (NOAEL) in rats and dogs was 30 mg/kg/day and 25 mg/kg/day, respectively.


Assuntos
Antibacterianos/toxicidade , Fluoroquinolonas/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Animais , Antibacterianos/administração & dosagem , Cães , Relação Dose-Resposta a Droga , Feminino , Fluoroquinolonas/administração & dosagem , Infusões Intravenosas , Rim/patologia , Fígado/patologia , Masculino , Nível de Efeito Adverso não Observado , Ratos , Ratos Sprague-Dawley
18.
J Ethnopharmacol ; 117(2): 300-8, 2008 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-18358653

RESUMO

AIM OF THE STUDY: To investigate the protective effects of dehydrocavidine (DC), a main active ingredient of Corydalis saxicola Bunting (Yanhuanglian), on carbon tetrachloride (CCl4)-induced hepatotoxicity and the possible mechanisms involved in male Sprague-Dawley rats. MATERIALS AND METHODS: Acute hepatotoxicity was induced by CCl4 intoxication in rats. Serum biological analysis, lipid peroxides and antioxidants estimation, histopathological studies were carried out. RESULTS: Both pre-treatment with DC prior to CCl4 administration and post-treatment with DC after CCl4 administration significantly prevented increases in serum enzymatic activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and total bilirubin (TBIL). In addition, pre- and post-treatment with DC also significantly prevented formation of hepatic malondialdehyde (MDA), depletion of glutathione peroxidase (GPx) and depression of superoxide dismutase (SOD) in the liver of CCl4-intoxicated rats. ALT, AST, LDH, ALP and TBILL levels, as well as MDA, SOD and GPx activities were unaffected in normal rats by treatment with DC alone. GST, a phase II enzyme, had no significant changes during our experiments. Histopathological changes induced by CCl4 were also significantly attenuated by DC treatment in both preventive and curative experiments. CONCLUSIONS: DC has a potent hepatoprotective effect on CCl4-induced liver injury in rats through its antioxidant activity.


Assuntos
Alcaloides de Berberina/farmacologia , Intoxicação por Tetracloreto de Carbono/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Animais , Antioxidantes/farmacologia , Cristalização , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Testes de Função Hepática , Masculino , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(11): 2609-14, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19271501

RESUMO

Serum albumin is the most abundant protein in plasma. It can bind with many intrinsic and extrinsic materials. The study of the interaction between serum albumin and drugs is a very important task in life science and chemistry. Quinolone drug is a kind of antibacterial drugs which have been used widely in clinical medicine, but its pharmacology and toxicology still have to be studied further. Sinafloxacin is a new quinolone antibiotics. The interaction between sinafloxacin and bovine serum albumin (BSA) at different temperatures and pH was investigated by fluorescence and UV absorption spectroscopy. The experimental results demonstrate that the fluorescence quenching of BSA by sinafloxacin is a result of the formation of sinafloxacin-BSA complex and the quenching mechanism is mainly static quenching. The interaction association constants of BSA and sinafloxacin were determined from the double reciprocal Lineweaver-Burk plot. The binding distance(r = 3.64 Rnm) and energy transfer efficiency (E = 0.163) between donor (BSA) and acceptor (sinafloxacin) were obtained based on Förster's non-radiative energy transfer theory. There is a strong interaction between sinafloxacin and BSA. From thermodynamic coordination it can be judged that the binding force between sinafloxacin and BSA is mainly electro-static force. The effect of sinafloxacin on the conformation of BSA was analyzed by synchronous fluorescence spectrometry and three-dimensional fluorescence spectrometry. The emission maximum of tyrosine residues does not show a significant shift, while the small blue shift of tryptophan residues indicates that the hydrophobicity of microenvironment was increased. In addition, in the plasma, there are some metal ions, which can participate in many important vital actions and affect the reactions of the drugs with the serum albumins. So the effect of Cu(II), Fe(III), Zn( II) and Mg(II) on the binding constant of sinafloxacin to BSA was also discussed and it was shown that the interaction between BSA and sinafloxacin was decreased. In short, the results offer a reference for the studies on the biological effects and action mechanism of sinafloxacin with albumins in vivo.


Assuntos
Fluoroquinolonas/química , Metais/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Animais , Bovinos , Cobre/química , Concentração de Íons de Hidrogênio , Ferro/química , Magnésio/química , Temperatura , Zinco/química
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