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2.
Molecules ; 24(13)2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261913

RESUMO

A novel strategy was developed to identify hepatotoxic compounds in traditional Chinese medicines (TCMs). It is based on the exposure of HL-7702 cells to a TCM extract, followed by the identification and further determination of potential hepatotoxic compounds accumulated in the cells by liquid chromatography-tandem mass spectrometry (LC-MS/MS). As a case study, potential hepatotoxic components in Chelidonium majus L. were screened out. Five alkaloids (sanguinarine, coptisine, chelerythrine, protopine, and chelidonine) were identified by LC-MS/MS within 10 min, and their intracellular concentrations were first simultaneously measured by LC-MS/MS with a run time of 4 min. A cell viability assay was performed to assess the cytotoxicity of each alkaloid. With their higher intracellular concentrations, sanguinarine, coptisine, and chelerythrine were identified as the main hepatotoxic constituents in Ch. majus. The study provides a powerful tool for the fast prediction of cytotoxic components in complex natural mixtures on a high-throughput basis.


Assuntos
Alcaloides/análise , Alcaloides/toxicidade , Chelidonium/química , Fígado/citologia , Benzofenantridinas/análise , Benzofenantridinas/toxicidade , Berberina/análogos & derivados , Berberina/análise , Berberina/toxicidade , Alcaloides de Berberina/análise , Alcaloides de Berberina/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Avaliação Pré-Clínica de Medicamentos , Humanos , Isoquinolinas/análise , Isoquinolinas/toxicidade , Fígado/química , Fígado/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem , Testes de Toxicidade
3.
Food Chem Toxicol ; 131: 110583, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31220533

RESUMO

We investigated the anti-inflammatory activity of protopine (PTP) and sought to determine its mechanism of action in LPS-stimulated BV2 cells and a carrageenan (CA)-induced mouse model. Treatment with PTP (5, 10, and 20 µM) significantly suppresses the secretion of NO and PGE2 in a concentration-dependent manner without affecting cell viability by downregulating iNOS and COX-2 expression in LPS-induced BV2 cells. PTP also attenuates the production of pro-inflammatory chemokines, such as MCP-1, and cytokines, including TNF-α, IL-1ß and IL-6, and augments the expression of the anti-inflammatory cytokine IL-10. In addition, PTP suppresses the nuclear translocation of NF-κB by hindering the degradation of IκB and downregulating the expression of mitogen-activated protein kinases (MAPKs), including p38, ERK1/2 and JNK protein. Furthermore, PTP treatment significantly suppresses CA-induced paw oedema in mice compared to that seen in untreated mice. Expression of iNOS and COX-2 proteins is also abrogated by PTP (50 mg/kg) treatment in CA-induced mice. PTP treatment also abolishes IκB phosphorylation, which hinders the activation of NF-κB. Collectively, these results suggest PTP has potential for attenuating CA- and LPS-induced inflammatory symptoms through modulation of MAPKs/NF-κB signaling cascades.


Assuntos
Anti-Inflamatórios/uso terapêutico , Benzofenantridinas/uso terapêutico , Alcaloides de Berberina/uso terapêutico , Inflamação/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Animais , Anti-Inflamatórios/toxicidade , Benzofenantridinas/toxicidade , Alcaloides de Berberina/toxicidade , Carragenina , Linhagem Celular Transformada , Quimiocinas/metabolismo , Inflamação/induzido quimicamente , Lipopolissacarídeos , Camundongos Endogâmicos ICR , Proteínas Quinases Ativadas por Mitógeno/química , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos
4.
Biochimie ; 162: 176-184, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31051209

RESUMO

Palmatine is a natural isoquinoline alkaloid and has been widely used in pharmaceutical field. The purpose of this review is to provide the latest and comprehensive information on the pharmacology, toxicity and pharmacokinetics of palmatine in the past, to explore the therapeutic potential of this compound and look for ways to reduce toxicity. Information on palmatine was collected from the internet database PubMed, Elsevier, ResearchGate, Web of Science, Wiley Online Library and Europe PMC using a combination of keywords including "pharmacology", "toxicology", "pharmacokinetics". All studies of this genus were included in this review until March 2019. Palmatine has a wide spectrum of pharmacological effects, including anti-cancer, anti-oxidation, anti-inflammatory, neuroprotection, anti-bacterial, anti-viral and regulating blood lipids. However, palmatine has obvious DNA toxicity, and has a complex effect on metabolic enzymes in the liver. Pharmacokinetic studies have demonstrated that glucuronidation and sulfation are the main metabolic pathways of palmatine. Palmatine can be used in many diseases. Future research directions include: how the concentration of palmatine affects pharmacological effects and toxicity; the mechanism of synergy between palmatine and other protoberberine alkaloid; Structural modification of palmatine is one of the key methods to enhance pharmacological activity and reduce activity.


Assuntos
Bactérias/efeitos dos fármacos , Alcaloides de Berberina , Medicamentos de Ervas Chinesas , Extratos Vegetais , Animais , Alcaloides de Berberina/farmacocinética , Alcaloides de Berberina/farmacologia , Alcaloides de Berberina/toxicidade , Células Cultivadas , Bases de Dados Bibliográficas , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/toxicidade , Humanos , Camundongos , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Coelhos , Ratos
5.
Chem Biol Interact ; 268: 47-52, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28257954

RESUMO

The aim of this study was to investigate the effects of tetrahydroberberine (THB) and tetrahydropalmatine (THP) on the expression of mouse liver cytochrome P450s, and evaluate their liver toxicity in mice. Real-time polymerase chain reaction (PCR) and western blot analyses were used to analyze the expression of major P450 isoforms. Liver toxicity was evaluated by measuring serum biochemical parameters and performing histopathological analysis. The real-time PCR results showed that THB induced Cyp1a2 (1.66 ± 0.34 fold, P < 0.05), Cyp3a11 (1.57 ± 0.24 fold, P < 0.05), and Cyp2e1 (1.75 ± 0.97 fold, P < 0.05) mRNA expression, while THP inhibited Cyp1a2 (0.66 ± 0.12 fold, P < 0.05) mRNA expression. The western blot results confirmed that the expression of CYP1A2, CYP3A, and CYP2E1 proteins in the mouse liver was induced by THB, whereas that of CYP1A2 was inhibited by THP. Toxicological studies showed that THB (40 mg/kg, oral gavage) increased mouse serum aspartate transaminase and total bilirubin, and liver malondialdehyde levels, and induced liver edema. No obvious changes in serum and liver tissue biochemical parameters were found and no significant pathological changes were detected in liver tissues after THP administration. Our results provide more information on the toxicity of THB and THP, and their related drug-drug interactions.


Assuntos
Alcaloides de Berberina/toxicidade , Berberina/análogos & derivados , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Animais , Aspartato Aminotransferases/sangue , Berberina/toxicidade , Bilirrubina/sangue , Citocromo P-450 CYP3A , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo
6.
Toxicol Lett ; 221(1): 64-72, 2013 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-23747414

RESUMO

Goldenseal has been used for the treatment of a wide variety of ailments including gastrointestinal disturbances, urinary tract disorders, and inflammation. The five major alkaloid constituents in goldenseal are berberine, palmatine, hydrastine, hydrastinine, and canadine. When goldenseal was evaluated by the National Toxicology Program (NTP) in the standard 2-year bioassay, goldenseal induced an increase in liver tumors in rats and mice; however, the mechanism of goldenseal-associated liver carcinogenicity remains unknown. In this study, the toxicity of the five goldenseal alkaloid constituents was characterized, and their toxic potencies were compared. As measured by the Comet assay and the expression of γ-H2A.X, berberine, followed by palmatine, appeared to be the most potent DNA damage inducer in human hepatoma HepG2 cells. Berberine and palmatine suppressed the activities of both topoisomerase (Topo) I and II. In berberine-treated cells, DNA damage was shown to be directly associated with the inhibitory effect of Topo II, but not Topo I by silencing gene of Topo I or Topo II. In addition, DNA damage was also observed when cells were treated with commercially available goldenseal extracts and the extent of DNA damage was positively correlated to the berberine content. Our findings suggest that the Topo II inhibitory effect may contribute to berberine- and goldenseal-induced genotoxicity and tumorigenicity.


Assuntos
Alcaloides/toxicidade , DNA/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hydrastis/metabolismo , Mutagênicos/toxicidade , Berberina/química , Berberina/metabolismo , Berberina/toxicidade , Alcaloides de Berberina/química , Alcaloides de Berberina/metabolismo , Alcaloides de Berberina/toxicidade , Ensaio Cometa , Dano ao DNA , DNA Topoisomerases Tipo I/genética , DNA Topoisomerases Tipo I/metabolismo , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Células Hep G2 , Hepatócitos/metabolismo , Histonas/metabolismo , Humanos , Hydrastis/química , Extratos Vegetais/química , Extratos Vegetais/toxicidade , RNA Interferente Pequeno/genética , Relação Estrutura-Atividade
7.
J Ethnopharmacol ; 145(1): 303-10, 2013 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-23159469

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Rhizoma Coptidis (RC), a widely used traditional Chinese medicine, has been used for the treatment of heat-clearing and detoxifying, but there is very little information on its safety. AIM OF THE STUDY: To provide information on the safety of RC, we evaluated the toxicity of the crude RC and RC alkaloids (berberine, coptisine, palmatine and epiberberine) including cytotoxicity, acute toxicity in mice and sub-chronic toxicity in rats. MATERIALS AND METHODS: The cytotoxicity of RC alkaloids was tested in HepG2 and 3T3-L1 cells by the MTT assay. The acute toxicity of RC alkaloids was tested in mice and the mortality was calculated at the end of experiment. For sub-chronic toxicity study, the rats were treated with the RC alkaloids at a dose of 156 mg/kg/day and RC at a dose of 521 mg/kg/day for 90 days. Mortality, clinical signs, body weight changes, organ weights, urinalysis and hematological parameters, gross necropsy and histopathology were monitored during the study period. RESULTS: The cell assay indicates that the IC(50) values of berberine, coptisine, palmatine and epiberberine in HepG2 cells were 48.17, 64.81, 112.80 and 120.58 µg/mL, which in 3T3-L1 cells were 41.76, 56.48, 84.32 and 104.18 µg/mL, respectively. In the acute toxicity assay, the LD(50) values of four alkaloids were 713.57, 852.12, 1533.68 and 1360 mg/kg, respectively. However, in the sub-chronic toxicity study, no mortality and morbidity were observed which could be related to RC alkaloids and RC treatment. Besides, there was no abnormality in clinical signs, body weights, organ weights, urinalysis, hematological parameters, gross necropsy and histopathology in any of the animals after the oral administration of RC alkaloids and RC. CONCLUSIONS: Taking these results together, we came to the conclusion that the toxicity of berberine is the maximum and palmatine is the minimal in four RC alkaloids. The currently recommended doses of RC alkaloids and RC consumed are relatively safe.


Assuntos
Alcaloides/toxicidade , Berberina/análogos & derivados , Coptis/efeitos adversos , Medicamentos de Ervas Chinesas/toxicidade , Rizoma/efeitos adversos , Células 3T3-L1 , Animais , Berberina/toxicidade , Alcaloides de Berberina/toxicidade , Proteínas Sanguíneas/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Coptis/química , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Feminino , Células Hep G2 , Humanos , Concentração Inibidora 50 , Dose Letal Mediana , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Rizoma/química
8.
Molecules ; 17(10): 11294-302, 2012 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-23011273

RESUMO

By introducing long carbon-chain alkyl groups at the C-13 position of berberine and palmatine, 13-n-hexyl/13-n-octyl berberine and palmatine chloride analogues 4a-d were synthesized and examined by MTT assays for cytotoxic activity in seven human cancer cell lines (7701QGY, SMMC7721, HepG2, CEM, CEM/VCR, KIII, Lewis), yielding IC50 values of 0.02 ± 0.01-13.58 ± 2.84 µM. 13-n-Octyl palmatine (compound 4d) gave the most potent inhibitor activity, with an IC50 of 0.02 ± 0.01 µM for SMMC7721. In all cases, the 13-n-alkyl berberine and palmatine analogues 4a-d were more cytotoxic than berberine and palmatine. In addition, compounds 4a-d also exhibited more potent cytotoxicity than berberine and palmatine in mice with S180 sarcoma xenografted in vivo. The primary screening results indicated that the 13-n-hexyl/13-n-octyl berberine and palmatine analogues might be valuable source for new potent anticancer drug candidates.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Alcaloides de Berberina/química , Alcaloides de Berberina/toxicidade , Berberina/química , Berberina/toxicidade , Animais , Antineoplásicos/farmacologia , Berberina/farmacologia , Alcaloides de Berberina/farmacologia , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Chemosphere ; 87(7): 775-81, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22305193

RESUMO

The interaction of the phototoxic alkaloid coralyne with bovine and human serum albumins (BSA, HSA) was investigated. Absorbance and fluorescence quenching experiments revealed the formation of strong complexes. Based on the binding parameters calculated from Stern-Volmer quenching method, coralyne has higher affinity to BSA (~10(5) M(-1)) compared to HSA (~10(4) M(-1)). Forster resonance energy transfer studies showed that the specific binding distances between Trp (donor) of the proteins and coralyne (acceptor) were 2.95 and 3.10 nm, respectively. The bindings were favored by negative enthalpy and a stronger favorable entropy contribution. The heat capacity values for binding to BSA and HSA were similar, indicating the involvement of similar molecular forces in the complexation. Competitive binding experiments using site markers demonstrated that coralyne binds to site I (subdomain IIA) of both proteins. The secondary structure of the proteins was altered, suggesting a small but definitive partial unfolding on complexation.


Assuntos
Alcaloides de Berberina/metabolismo , Substâncias Perigosas/metabolismo , Soroalbumina Bovina/metabolismo , Albumina Sérica/metabolismo , Animais , Alcaloides de Berberina/química , Alcaloides de Berberina/toxicidade , Bovinos , Transferência Ressonante de Energia de Fluorescência , Humanos , Processos Fotoquímicos , Albumina Sérica/química , Soroalbumina Bovina/química
10.
Arch Pharm (Weinheim) ; 343(4): 207-14, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20222063

RESUMO

The affinities of tetrahydroprotoberberines for dopamine receptors dramatically decrease after cleaving the central C-N bond to the analogous ten-membered dibenzo[c,g]azecines [1]. In the present work, we also synthesized eleven-membered homologues of these heterocycles and measured the affinities of the resulting dibenzazaundecenes and their underlying homoberberines for human dopamine receptors as well as the cytotoxic effects of all target compounds on human glia cells. The tetracyclic iso-C-homoberberine-derivatives revealed to be D(4)-selective antagonists, while all other active compounds showed a significant D(1)/D(5) selectivity. Distances in energy-minimized conformations were measured in order to explain our findings.


Assuntos
Antipsicóticos/farmacologia , Alcaloides de Berberina/farmacologia , Antagonistas de Dopamina/farmacologia , Receptores Dopaminérgicos/efeitos dos fármacos , Antipsicóticos/síntese química , Antipsicóticos/metabolismo , Alcaloides de Berberina/síntese química , Alcaloides de Berberina/metabolismo , Alcaloides de Berberina/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Desenho Assistido por Computador , Antagonistas de Dopamina/síntese química , Antagonistas de Dopamina/metabolismo , Antagonistas de Dopamina/toxicidade , Relação Dose-Resposta a Droga , Desenho de Fármacos , Humanos , Modelos Moleculares , Estrutura Molecular , Neuroglia/efeitos dos fármacos , Neuroglia/patologia , Ensaio Radioligante , Receptores Dopaminérgicos/metabolismo , Receptores de Dopamina D1/antagonistas & inibidores , Receptores de Dopamina D4/antagonistas & inibidores , Receptores de Dopamina D5/antagonistas & inibidores , Relação Estrutura-Atividade
11.
Toxicol Lett ; 194(1-2): 8-15, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20109541

RESUMO

The analgesic agent levo-tetrahydropalmatine (l-THP) was reported to be associated with acute or chronic hepatitis in clinical practice. We found that l-THP can induce apoptosis in the hepatocytes of BALB/c mice and human normal liver L-02 (L-02) cells. Several key molecules, including caspase-3, Bcl-2, BAD and Bax, were modulated by l-THP treatment. A novel high-throughput proteomic approach based on 2D-nano-LC-MS/MS was applied to simultaneously evaluate the alterations of global protein expression involved in the response of l-THP treatment in L-02 cells. A total of 156 deregulated proteins were identified, among which 12 proteins play regulatory or constitutive roles in the apoptosis pathways. Further analyses of two proteins (mTOR and MEK2) by Western Blots confirmed that these proteins were expressed at lower levels in l-THP-treated L-02 cells compared with those of control. The current study provided detailed evidence to support that l-THP is capable of inducing apoptosis in mammalian liver cells and improve the understanding of mechanisms of l-THP-induced hepatotoxicity.


Assuntos
Analgésicos/toxicidade , Apoptose , Alcaloides de Berberina/toxicidade , Hepatócitos/efeitos dos fármacos , Tetra-Hidronaftalenos/toxicidade , Analgésicos/química , Analgésicos/metabolismo , Animais , Alcaloides de Berberina/química , Alcaloides de Berberina/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Cromatografia Líquida , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MAP Quinase Quinase 2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Serina-Treonina Quinases/metabolismo , Proteômica/métodos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Serina-Treonina Quinases TOR , Espectrometria de Massas em Tandem , Tetra-Hidronaftalenos/química , Tetra-Hidronaftalenos/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo
12.
Toxicol Sci ; 105(2): 408-17, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18599498

RESUMO

Berberine [Natural Yellow 18, 5,6-dihydro-9,10-dimethoxybenzo(g)-1,3-benzodioxolo (5,6-a) quinolizinium] is an alkaloid present in plants of the Berberidaceae family and used in traditional Chinese and North American medicine. We have previously demonstrated that berberine causes mitochondrial depolarization and fragmentation, with simultaneous increase in oxidative stress. We also demonstrated that berberine causes an inhibition of mitochondrial respiration and a decrease on calcium loading capacity through induction of the mitochondrial permeability transition (MPT). The objective of the present work is to investigate a common target for both induction of the MPT and inhibition of respiration. The hypothesis is that berberine induces the MPT through interacting with the adenine nucleotide translocator (ANT). By measuring induction of the MPT through increased mitochondrial swelling, membrane depolarization and loss of calcium retention, we observed that the effects of berberine were not inhibited by bongkrekic acid although adenosine diphosphate (ADP)/oligomycin completely prevented the MPT. Also, we observed that berberine increased the depolarization effect of oleic acid on liver mitochondria. The initial depolarization observed when berberine is added to mitochondria was not affected by ANT inhibitors. Taken together, we propose that berberine acts on the ANT, altering the binding of the protein to bongkrekic acid but not to cyclosporin A or ADP. It is also clear that the membrane potential is required for berberine effects, most likely for allowing for its mitochondrial accumulation. Mitochondrial effects of berberine can be relevant not only for its proposed antitumor activity but also for the assessment of its organ toxicity, depending on factors such as tissue accumulation or delivery.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Alcaloides de Berberina/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Translocases Mitocondriais de ADP e ATP/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Difosfato de Adenosina/metabolismo , Animais , Atractilosídeo/análogos & derivados , Atractilosídeo/farmacologia , Ácido Bongcréquico/farmacologia , Cálcio/metabolismo , Respiração Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/enzimologia , Translocases Mitocondriais de ADP e ATP/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Dilatação Mitocondrial/efeitos dos fármacos , Ácido Oleico/farmacologia , Oligomicinas/farmacologia , Ratos , Ratos Wistar , Fatores de Tempo , Desacopladores/farmacologia
13.
Afr J Med Med Sci ; 36(4): 317-23, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18564647

RESUMO

We have examined the cumulative effects of the protoberberine alkaloidal fraction (AF) of the stein bark ethanolic extracts of Enantia chlorantha on some body tissues and organs as well as on certain biochemical and metabolic parameters in mice. Acute and sub-chronic toxicity studies of the alkaloidal fractions of Enantia chlorantha were carried out in 120 mice using oral and intraperitoneal administrations. Fatality was not recorded in mice injected intraperitonealy with 100 mg kg(-1) and 150 mg kg(-1) dose level but larger doses resulted in death and the mean lethal dose (LD50) toxicity studies showed neither behavioural/untoward reactions nor death in any of the animals. The histopathological examination of the test animals when compared with the control revealed that, the sub-chronic use of the alkaloidal fractions does not have any pathological effects (lesion) on the organs examined (the stomach, the kidney, the oesophagus and the liver) except the lungs which showed mild and moderate oedema. The biochemical and metabolic analysis of the mice plasma did not show any significant difference when the corresponding values for the test mice were compared with the control mice (P > 0.05) at the end of the 14 days treatment using both 20 mg kg(-1) and 2 mg kg(-1) dose levels. The results obtained in this study suggest the relative safety of short-term use of preparations containing E. chlorantha, a very popular antimalarial herbal remedy in Southern Nigeria.


Assuntos
Annonaceae , Alcaloides de Berberina/toxicidade , Medicinas Tradicionais Africanas , Extratos Vegetais/toxicidade , Animais , Avaliação Pré-Clínica de Medicamentos , Feminino , Dose Letal Mediana , Masculino , Camundongos
14.
Chem Res Toxicol ; 19(6): 739-44, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16780351

RESUMO

Goldenseal is an herb that is widely used in dietary supplements, eye washes, and skin lotions. The presence of Goldenseal root powder in dietary supplements and the topical application of Goldenseal preparations raise the possibility that an adverse phototoxic reaction may result from an interaction between its constituent alkaloids and light in exposed tissues. We have previously shown that berberine, the major alkaloid in Goldenseal powder, in combination with UVA causes DNA damage and cell death in HaCaT keratinocytes [(2001) Chem. Res. Toxicol. 14, 1529]. We have studied the photochemical and photobiological properties of four minor alkaloids found in Goldenseal, namely, hydrastine, palmatine, canadine, and hydrastinine. UVA radiation of palmatine in aqueous solutions generated no (1)O(2), but in CH(2)Cl(2), copious amounts of (1)O(2) were detected (Phi = 0.2). Palmatine also photogenerated oxygen-centered radicals, (*)OH and O(2)(*)(-) in aerated aqueous buffer and acetonitrile, respectively, as detected by the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO). In nitrogen-sparged acetonitrile containing DMPO, we observed the neutral palmatine radical formed by one-electron reduction. UVA irradiation (4 J/cm(2)) of HaCaT keratinocytes in the presence of palmatine (50 microM) resulted in a 50% decrease in cell viability but no DNA damage as measured by the comet assay. UVA irradiation of hydrastine, hydrastinine, or canadine (50 microM) did not cause DNA damage or cell death in keratinocytes. Although palmatine is photoactive, it is present in such small amounts in Goldenseal root powder that the phototoxicity of the herb is most likely due to berberine, the major constituent alkaloid.


Assuntos
Alcaloides/química , Alcaloides/toxicidade , Hydrastis/química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/toxicidade , Benzilisoquinolinas , Berberina/análogos & derivados , Berberina/química , Berberina/toxicidade , Alcaloides de Berberina/química , Alcaloides de Berberina/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Humanos , Estrutura Molecular , Oxigênio/química , Fotoquímica , Análise Espectral
15.
Int J Biol Macromol ; 39(4-5): 210-21, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16678250

RESUMO

The interaction of the protoberberine alkaloid palmatine with single and double stranded structures of poly(A) was studied by various biophysical techniques. Comparative binding studies were also performed with double stranded DNA, t-RNA, poly(C).poly(G), poly(U) and poly(C). The results of competition dialysis, fluorescence, and absorption spectral studies converge to reveal the molecular aspects of the strong and specific binding of palmatine to single stranded poly(A). The binding affinity of palmatine to natural DNA, t-RNA and double stranded poly(A) was weaker while no binding was apparent with single stranded poly(U), poly(C) and double stranded poly(C).poly(G). The strong affinity of the alkaloid to single stranded poly(A) in comparison to the double stranded structure was also revealed from circular dichroic and viscometric studies. The effect of [Na+] ion concentration on the binding process revealed the significant role of electrostatic forces in the complexation. The presence of bound alkaloid also remarkably affected denaturation-renaturation of stacked helical poly(A). The energetics of the strong binding to poly(A) was studied from thermodynamic estimation from van Hoff' analysis of the temperature dependent binding constants and ultra sensitive isothermal titration calorimertry, both suggesting the binding to be exothermic and enthalpy driven. This study provides detailed insight into the binding specificity of the natural alkaloid to single stranded poly(A) over several other single and double stranded nucleic acid structures suggesting its potential as a lead compound for RNA based drug targeting.


Assuntos
Alcaloides de Berberina/química , Alcaloides de Berberina/toxicidade , Poli A/química , Sítios de Ligação , Dicroísmo Circular , DNA/química , DNA/efeitos dos fármacos , Diálise , Humanos , Técnicas In Vitro , Cinética , Masculino , Estrutura Molecular , Conformação de Ácido Nucleico , Concentração Osmolar , Espectrometria de Fluorescência , Espectrofotometria , Termodinâmica , Viscosidade
16.
Neuroscience ; 120(2): 541-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12890523

RESUMO

The enzyme 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) is involved in the generation of neuroactive steroids through ring-A-reduction of hormonal precursors. We examined the developmental regulation of, gender differences in, and effects of hormonal manipulations on the expression of 3 alpha-HSD in the rat hippocampus. High levels of 3 alpha-HSD mRNA were found on postnatal day 7, coinciding with the stress hyporesponsive period in the rat. Gender differences in 3 alpha-HSD expression were documented during puberty, but not in adulthood. Adrenalectomy and gonadectomy, and supplementation with individual steroid hormones influenced 3 alpha-HSD expression in a gender-specific mode. We also demonstrate that the manifestation of behavioral and endocrine consequences of early life stress depends on the individual's gender and gonadal status. Males are liable to aftereffects of neonatal maternal deprivation, regardless of their adult gonadal status. In females, however, anxiogenic aftereffects of neonatal stress become apparent only after gonadectomy. These data suggest that (i) transient increase of neurosteroid biosynthesis may contribute to stress hyporesponsiveness during early infancy; (ii) gonadal steroids regulate 3 alpha-HSD expression in the hippocampus in a sex-specific mode; (iii) physiological sex steroid secretions in females may mask behavioral consequences of adverse early life events, and (iv) concomitant treatment with the neurosteroid THP counteracts behavioral and endocrine dysregulation induced by neonatal stress in both genders.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Transtornos de Ansiedade/enzimologia , Encéfalo/enzimologia , Desoxicorticosterona/análogos & derivados , Regulação Enzimológica da Expressão Gênica , Caracteres Sexuais , 3-Hidroxiesteroide Desidrogenases/genética , Animais , Transtornos de Ansiedade/induzido quimicamente , Transtornos de Ansiedade/fisiopatologia , Alcaloides de Berberina/toxicidade , Encéfalo/anatomia & histologia , Castração/métodos , Corticosterona/sangue , Feminino , Hibridização In Situ/métodos , Masculino , Gravidez , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo
17.
Artigo em Inglês | MEDLINE | ID: mdl-12726842

RESUMO

Eschscholtzia californica preparations are in use as phytopharmaceuticals and as herbal drugs. Studies are described on the metabolism and the toxicological analysis of the Eschscholtzia californica alkaloids californine and protopine in rat urine using gas chromatography-mass spectrometry. The identified metabolites indicated that californine is extensively metabolized by N-demethylation and/or single or double demethylenation with consecutive catechol-O-methylation of one of the hydroxy groups. Protopine, however, only undergoes extensive demethylenation of the 2,3-methylenedioxy group followed by catechol-O-methylation. All phenolic hydroxy metabolites were found to be partly conjugated. The authors' systematic toxicological analysis procedure using full-scan gas chromatography-mass spectrometry after acid hydrolysis, liquid-liquid extraction and microwave-assisted acetylation allowed the detection of the main metabolites of californine and protopine in rat urine after a dose which should correspond to that of drug users. Therefore, use of Eschscholtzia californica preparations should also be detectable in human urine by the authors' systematic toxicological analysis procedure.


Assuntos
Alcaloides de Berberina/toxicidade , Eschscholzia/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Isoquinolinas/toxicidade , Animais , Benzofenantridinas , Alcaloides de Berberina/urina , Isoquinolinas/urina , Masculino , Ratos
18.
Biochemistry ; 36(41): 12542-53, 1997 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-9376359

RESUMO

Spectroscopic, calorimetric, DNA cleavage, electrophoretic, and computer modeling techniques have been employed to characterize the DNA binding and topoisomerase poisoning properties of three protoberberine analogs, 8-desmethylcoralyne (DMC), 5,6-dihydro-8-desmethylcoralyne (DHDMC), and palmatine, which differ in the chemical structures of their B- and/or D-rings. DNA topoisomerase-mediated cleavage assays revealed that these compounds were unable to poison mammalian type II topoisomerase. By contrast, the three protoberberine analogs poisoned human topoisomerase I according to the following hierarchy: DHDMC > DMC > palmatine. DNA binding by all three protoberberine analogs induced negative flow linear dichroism signals as well as unwinding of the host duplex. These two observations are consistent with an intercalative mode of protoberberine binding to duplex DNA. However, a comparison of the DNA binding properties for DMC and DHDMC, which differ only by the state of saturation at the 5,6 positions of the B-ring, revealed that the protoberberine analogs do not "behave" like classic DNA intercalators. Specifically, saturation of the 5-6 double bond in the B-ring of DMC, thereby converting it to the DHDMC molecule, was associated with enhanced DNA unwinding as well as a reversal of DNA binding preference from a DNA duplex with an inaccessible or occluded minor groove {poly[d(G-C)]2} to DNA duplexes with accessible or unobstructed minor grooves {poly[d(A-T)]2 and poly[d(I-C)]2}. In addition, a comparison of the DNA binding properties for DHDMC and palmatine revealed that transferring the 11-methoxy moiety on the D-ring of DHDMC to the 9 position, thereby converting it to palmatine, was associated with a reduction in binding affinity for both duplexes with unobstructed minor grooves as well as for duplexes with occluded minor grooves. These DNA binding properties are consistent with a "mixed-mode" DNA binding model for protoberberines in which a portion of the ligand molecule intercalates into the double helix, while the nonintercalated portion of the ligand molecule protrudes into the minor groove of the host duplex, where it is thereby available for interactions with atoms lining the floor and/or walls of the minor groove. Furthermore, saturation at the 5,6 positions of the B-ring, which causes the A-ring to be tilted relative to the plane formed by rings C and D, appears to stabilize the interaction between the host duplex and the minor groove-directed portion of the protoberberine ligand. Computer modeling studies on the DHDMC-poly[d(A-T)]2 complex suggest that this interaction may involve van der Waals contacts between the ligand A-ring and backbone sugar atoms lining the minor groove of the host duplex. The hierarchy of topoisomerase I poisoning noted above suggests that this minor groove-directed interaction may play an important role in topoisomerase I poisoning by protoberberine analogs. In the aggregate, our results presented here, coupled with the recent demonstration of topoisomerase I poisoning by minor groove-binding terbenzimidazoles [Sun, Q., Gatto, B., Yu, C., Liu, A. , Liu, L. F., & LaVoie, E. J. (1995) J. Med. Chem. 38, 3638-3644], suggest that minor groove-directed ligand-DNA interactions may be of general importance in the poisoning of topoisomerase I.


Assuntos
Alcaloides de Berberina/toxicidade , DNA Topoisomerases Tipo I/química , DNA/metabolismo , Calorimetria , DNA Topoisomerases Tipo I/metabolismo , DNA Topoisomerases Tipo I/toxicidade , Humanos , Ligantes , Inibidores da Topoisomerase I
19.
Farmakol Toksikol ; 46(4): 107-12, 1983.
Artigo em Russo | MEDLINE | ID: mdl-6137406

RESUMO

The Soviet plant tranquilizer gindarin (an isoquinoline series alkaloid I-tetrahydropalmatine) isolated from the tubers of Stephania glabra Miers was subjected to a preclinical study. As regards the toxicity measured during a single administration to the laboratory animals, gindarin may be classified with moderately toxic substances. Daily intragastric administration of gindarin to rats in doses of 20 and 60 mg/kg for 3 months is likely to give rise to the changes in functions of the CNS, liver and blood. In doses of 1--50 mg/kg gindarin does not exhibit any allergizing, mutagenic or teratogenic properties. Administration of the drug in doses of 1--50 mg/kg from the 1st to the 20th day of pregnancy has shown it to produce marked embryotoxic action. In view of this fact gindarin is contraindicated in pregnancy.


Assuntos
Alcaloides/toxicidade , Antipsicóticos/toxicidade , Alcaloides de Berberina/toxicidade , Animais , Células Sanguíneas/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Embrião de Mamíferos/efeitos dos fármacos , Feminino , Cobaias , Masculino , Camundongos , Gravidez , Ratos , Fatores de Tempo
20.
Nihon Yakurigaku Zasshi ; 72(7): 909-27, 1976 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-1035192

RESUMO

The behavioral effects of tetrahydroberberine (THB), tetrahydrocoptisine (THC), tetrahydropalmatine (THP) and tetrahydrojateorrhizine (THJ) were compared with those of chlorpromazine (CPZ) and benzodiazepines in mice and rats. Effects of THB were also determined by electroencephalography (EEG) in rabbits. THB was found to pharmacologically exert various actions similar to those of CPZ which is a major tranquilizer, however, the actions of THB were weaker than those of CPZ. Although THB alone did not induce catalepsy, it enhanced the cataleptogenic action of CPZ. At a dose over the effective levels, THB did not lower normal body temperature or induce muscle relaxation and loss of righting reflex. EEG activities in the frontal cortex areas were markedly affected by THB, e.g., fast waves in spontaneous EEG were converted to slow waves. THB and CPZ in a similar manner elicited a sustaining increase in hippocampal afterdischarge, but the action of THB was weaker than that of CPZ. The acute toxicity of THB was lower than that of CPZ and benzodiazepines and the depressant activity of THB almost equalled that of THC and THP, whereas the activity of 1-THB was 1.5 times as great as that of THB. These data indicate that THB, THC and THP may be a new type of tranquilizer.


Assuntos
Alcaloides de Berberina/farmacologia , Berberina/farmacologia , Tranquilizantes , Animais , Anticonvulsivantes , Apomorfina/antagonistas & inibidores , Aprendizagem da Esquiva/efeitos dos fármacos , Barbitúricos/farmacologia , Comportamento Animal/efeitos dos fármacos , Berberina/análogos & derivados , Berberina/toxicidade , Alcaloides de Berberina/toxicidade , Temperatura Corporal/efeitos dos fármacos , Catalepsia/induzido quimicamente , Comportamento Cooperativo/efeitos dos fármacos , Sinergismo Farmacológico , Eletroencefalografia , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Locomoção/efeitos dos fármacos , Masculino , Mescalina/antagonistas & inibidores , Metanfetamina/antagonistas & inibidores , Camundongos , Ratos , Sono/efeitos dos fármacos
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