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1.
Biochem Biophys Res Commun ; 667: 127-131, 2023 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-37216828

RESUMO

Retinal pigment epithelial (RPE) cells contribute to several clinical conditions resulting in retinal fibrotic scars. Myofibroblast trans-differentiation of RPE cells is a critical step in the process of retinal fibrosis. In this study, we investigated the effects of N-oleoyl dopamine (OLDA), a newer endocannabinoid with a structure distinct from classic endocannabinoids, on TGF-ß2-induced myofibroblast trans-differentiation of porcine RPE cells. Using an in vitro collagen matrix contraction assay, OLDA was found to inhibit TGF-ß2 induced contraction of collagen matrices by porcine RPE cells. This effect was concentration-dependent, with significant inhibition of contraction observed at 3 µM and 10 µM. OLDA did not affect the proliferation of porcine RPE cells. Immunocytochemistry showed that at 3 µM, OLDA decreased incorporation of α-SMA in the stress fibers of TGF-ß2-treated RPE cells. In addition, western blot analysis showed that 3 µM OLDA significantly downregulated TGF-ß2-induced α-SMA protein expression. Taken together these results demonstrate that OLDA inhibits TGF-ß induced myofibroblast trans-differentiation of RPE cells. It has been established that classic endocannabinoid such as anandamide, by activating the CB1 cannabinoid receptor, promote fibrosis in multiple organ systems. In contrast, this study demonstrates that OLDA, an endocannabinoid with a chemical structure distinct from classic endocannabinoids, inhibits myofibroblast trans-differentiation, an important step in fibrosis. Unlike classic endocannabinoids, OLDA has weak affinity for the CB1 receptor. Instead, OLDA acts on non-classic cannabinoid receptors such as GPR119, GPR6, and TRPV1. Therefore, our study indicates that the newer endocannabinoid OLDA and its non-classic cannabinoid receptors could potentially be novel therapeutic targets for treating ocular diseases involving retinal fibrosis and fibrotic pathologies in other organ systems.


Assuntos
Endocanabinoides , Epitélio Pigmentado da Retina , Animais , Suínos , Endocanabinoides/farmacologia , Endocanabinoides/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Fator de Crescimento Transformador beta2/farmacologia , Fator de Crescimento Transformador beta2/metabolismo , Dopamina/farmacologia , Dopamina/metabolismo , Miofibroblastos/metabolismo , Colágeno/metabolismo , Fibrose , Células Epiteliais/metabolismo , Receptores de Canabinoides/metabolismo , Transdiferenciação Celular , Pigmentos da Retina/metabolismo
2.
Cell Physiol Biochem ; 55(S5): 1-14, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33984199

RESUMO

Cannabidiol (CBD), the major non-intoxicating constituent of Cannabis sativa, has gained recent attention due to its putative therapeutic uses for a wide variety of diseases. CBD was discovered in the 1940s and its structure fully characterized in the 1960s. However, for many years most research efforts related to cannabis derived chemicals have focused on D9-tetrahydrocannabinol (THC). In contrast to THC, the lack of intoxicating psychoactivity associated with CBD highlights the potential of this cannabinoid for clinical drug development. This review details in vitro and in vivo studies of CBD related to the eye, the therapeutic potential of cannabidiol for various ocular conditions, and molecular targets and mechanisms for CBD-induced ocular effects. In addition, challenges of CBD applications for clinical ocular therapeutics and future directions are discussed.


Assuntos
Canabidiol/metabolismo , Animais , Cannabis/química , Dronabinol/metabolismo , Humanos , Transdução de Sinais/fisiologia
3.
Biochem Biophys Res Commun ; 522(4): 1041-1045, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31818461

RESUMO

The orphan G protein-coupled receptor 6 (GPR6) is highly expressed in the striatum and has been linked to multiple striatal pathologies. The identification of endogenous ligands and their mechanisms of action at GPR6 will help to elucidate the physiological and pathological roles of the receptor. In the current study, we tested the concentration-dependent effects of a variety of endocannabinoid-like N-acylamides on GPR6 signaling. Here, we demonstrate for the first time that N-arachidonoyl dopamine, N-docosahexaenoyl dopamine, N-oleoyl dopamine and N-palmitoyl dopamine exert inverse agonism at GPR6. This effect was concentration-dependent, with potencies in the micromolar range, and functionally selective for ß-arrestin2 recruitment. Structure-activity relationship studies demonstrate that both the N-acyl side chain and the dopamine head group are important for these ligands to act on GPR6. Our discovery of these N-acyl dopamines as endogenous inverse agonists for GPR6 moves us one step further in understanding the roles GPR6 play in neurodegenerative and neuropsychiatric disorders related to striatal dysfunction.


Assuntos
Descoberta de Drogas , Receptores Acoplados a Proteínas G/agonistas , Animais , Células CHO , Cricetinae , Cricetulus , AMP Cíclico/metabolismo , Dopamina/química , Dopamina/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , beta-Arrestina 2/metabolismo
4.
Biochem Biophys Res Commun ; 533(4): 1366-1370, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33097185

RESUMO

Nematode Caenorhabditis elegans (C. elegans) exhibited a vigorous swimming behavior in liquid medium. Addition of dopamine inhibited the swimming behavior, causing paralysis in 65% of wild-type nematodes. Interestingly, phytocannabinoids cannabidiol (CBD) or cannabidivarin (CBDV), caused paralysis in 40% of the animals. Knockout of DOP-3, the dopamine D2-like receptor critical for locomotor behavior, eliminated the paralysis induced by dopamine, CBD, and CBDV. In contrast, both CBD and CBDV caused paralysis in animals lacking CAT-2, an enzyme necessary for dopamine synthesis. Co-administration of dopamine with either CBD or CBDV caused paralysis similar to that of either phytocannabinoid treatment alone. These data support the notion that CBD and CBDV act as functional partial agonists on dopamine D2-like receptors in vivo. The discovery that dopamine receptor is involved in the actions of phytocannabinoids moves a significant step toward our understanding of the mechanisms for medical uses of cannabis in the treatment of neurological and psychiatric disorders.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efeitos dos fármacos , Canabidiol/farmacologia , Canabinoides/farmacologia , Receptores de Dopamina D2/metabolismo , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Dopamina/metabolismo , Dopamina/farmacologia , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Mutação , Paralisia/induzido quimicamente , Psicotrópicos/farmacologia , Receptores de Dopamina D2/genética
5.
Acta Pharmacol Sin ; 40(3): 300-308, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29941868

RESUMO

The G protein-coupled receptors 3, 6, and 12 (GPR3, GPR6, and GPR12) comprise a family of closely related orphan receptors with no confirmed endogenous ligands. These receptors are constitutively active and capable of signaling through G protein-mediated and non-G protein-mediated mechanisms. These orphan receptors have previously been reported to play important roles in many normal physiological functions and to be involved in a variety of pathological conditions. Although they are orphans, GPR3, GPR6, and GPR12 are phylogenetically most closely related to the cannabinoid receptors. Using ß-arrestin2 recruitment and cAMP accumulation assays, we recently found that the nonpsychoactive phytocannabinoid cannabidiol (CBD) is an inverse agonist for GPR3, GPR6, and GPR12. This discovery highlights these orphan receptors as potential new molecular targets for CBD, provides novel mechanisms of action, and suggests new therapeutic uses of CBD for illnesses such as Alzheimer's disease, Parkinson's disease, cancer, and infertility. Furthermore, identification of CBD as a new inverse agonist for GPR3, GPR6, and GPR12 provides the initial chemical scaffolds upon which potent and efficacious agents acting on these receptors can be developed, with the goal of developing chemical tools for studying these orphan receptors and ultimately new therapeutic agents.


Assuntos
Canabidiol/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Animais , Agonismo Inverso de Drogas , Humanos , Ligantes , Neurônios/metabolismo , Transdução de Sinais/fisiologia
6.
Biochem Biophys Res Commun ; 490(1): 17-21, 2017 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-28571738

RESUMO

GPR3 and GPR6 are members of a family of constitutively active, Gs protein-coupled receptors. Previously, it has been reported that GPR3 is involved in Alzheimer's disease whereas GPR6 plays potential roles in Parkinson's disease. GPR3 and GPR6 are considered orphan receptors because there are no confirmed endogenous agonists for them. However, GPR3 and GPR6 are phylogenetically related to the cannabinoid receptors. In this study, the activities of endocannabinoids and phytocannabinoids were tested on GPR3 and GPR6 using a ß-arrestin2 recruitment assay. Among the variety of cannabinoids tested, cannabidiol (CBD), the major non-psychoactive component of marijuana, significantly reduced ß-arrestin2 recruitment to both GPR3 and GPR6. In addition, the inhibitory effects of CBD on ß-arrestin2 recruitment were concentration-dependent for both GPR3 and GPR6, with a higher potency for GPR6. These data show that CBD acts as an inverse agonist at both GPR3 and GPR6 receptors. These results demonstrate for the first time that both GPR3 and GPR6 are novel molecular targets for CBD. Our discovery that CBD acts as a novel inverse agonist on both GPR3 and GPR6 indicates that some of the potential therapeutic effects of CBD (e.g. treatment of Alzheimer's disease and Parkinson's disease) may be mediated through these important receptors.


Assuntos
Canabidiol/farmacologia , Agonismo Inverso de Drogas , Receptores Acoplados a Proteínas G/agonistas , Humanos , Relação Estrutura-Atividade , beta-Arrestina 2/antagonistas & inibidores
7.
Biochem Biophys Res Commun ; 493(1): 451-454, 2017 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-28888984

RESUMO

GPR12 is a constitutively active, Gs protein-coupled receptor that currently has no confirmed endogenous ligands. GPR12 may be involved in physiological processes such as maintenance of oocyte meiotic arrest and brain development, as well as pathological conditions such as metastatic cancer. In this study, the potential effects of various classes of cannabinoids on GPR12 were tested using a cAMP accumulation assay. Our data demonstrate that cannabidiol (CBD), a major non-psychoactive phytocannabinoid, acted as an inverse agonist to inhibit cAMP accumulation stimulated by the constitutively active GPR12. Thus, GPR12 is a novel molecular target for CBD. The structure-activity relationship studies of CBD indicate that both the free hydroxyl and the pentyl side chain are crucial for the effects of CBD on GPR12. Furthermore, studies using cholera toxin, which blocks Gs protein and pertussis toxin, which blocks Gi protein, revealed that Gs, but not Gi is involved in the inverse agonism of CBD on GPR12. CBD is a promising novel therapeutic agent for cancer, and GPR12 has been shown to alter viscoelasticity of metastatic cancer cells. Since we have demonstrated that CBD is an inverse agonist for GPR12, this provides novel mechanism of action for CBD, and an initial chemical scaffold upon which highly potent and efficacious agents acting on GPR12 may be developed with the ultimate goal of blocking cancer metastasis.


Assuntos
Canabidiol/administração & dosagem , AMP Cíclico/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Relação Dose-Resposta a Droga , Células HEK293 , Humanos
8.
J Biol Chem ; 289(29): 20259-72, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24855641

RESUMO

In this study, we applied a comprehensive G protein-coupled receptor-Gαi protein chemical cross-linking strategy to map the cannabinoid receptor subtype 2 (CB2)-Gαi interface and then used molecular dynamics simulations to explore the dynamics of complex formation. Three cross-link sites were identified using LC-MS/MS and electrospray ionization-MS/MS as follows: 1) a sulfhydryl cross-link between C3.53(134) in TMH3 and the Gαi C-terminal i-3 residue Cys-351; 2) a lysine cross-link between K6.35(245) in TMH6 and the Gαi C-terminal i-5 residue, Lys-349; and 3) a lysine cross-link between K5.64(215) in TMH5 and the Gαi α4ß6 loop residue, Lys-317. To investigate the dynamics and nature of the conformational changes involved in CB2·Gi complex formation, we carried out microsecond-time scale molecular dynamics simulations of the CB2 R*·Gαi1ß1γ2 complex embedded in a 1-palmitoyl-2-oleoyl-phosphatidylcholine bilayer, using cross-linking information as validation. Our results show that although molecular dynamics simulations started with the G protein orientation in the ß2-AR*·Gαsß1γ2 complex crystal structure, the Gαi1ß1γ2 protein reoriented itself within 300 ns. Two major changes occurred as follows. 1) The Gαi1 α5 helix tilt changed due to the outward movement of TMH5 in CB2 R*. 2) A 25° clockwise rotation of Gαi1ß1γ2 underneath CB2 R* occurred, with rotation ceasing when Pro-139 (IC-2 loop) anchors in a hydrophobic pocket on Gαi1 (Val-34, Leu-194, Phe-196, Phe-336, Thr-340, Ile-343, and Ile-344). In this complex, all three experimentally identified cross-links can occur. These findings should be relevant for other class A G protein-coupled receptors that couple to Gi proteins.


Assuntos
Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/química , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Receptor CB2 de Canabinoide/química , Receptor CB2 de Canabinoide/metabolismo , Cromatografia Líquida , Reagentes de Ligações Cruzadas , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Células HEK293 , Humanos , Modelos Moleculares , Simulação de Dinâmica Molecular , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas , Estrutura Secundária de Proteína , Receptor CB2 de Canabinoide/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
9.
Biochem Biophys Res Commun ; 443(1): 144-9, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24275139

RESUMO

The purpose of the current study was to investigate the ability of the third-generation selective estrogen receptor modulators (SERMs) bazedoxifene and lasofoxifene to bind and act on CB2 cannabinoid receptor. We have identified, for the first time, that CB2 is a novel target for bazedoxifene and lasofoxifene. Our results showed that bazedoxifene and lasofoxifene were able to compete for specific [(3)H]CP-55,940 binding to CB2 in a concentration-dependent manner. Our data also demonstrated that by acting on CB2, bazedoxifene and lasofoxifene concentration-dependently enhanced forskolin-stimulated cAMP accumulation. Furthermore, bazedoxifene and lasofoxifene caused parallel, rightward shifts of the CP-55,940, HU-210, and WIN55,212-2 concentration-response curves without altering the efficacy of these cannabinoid agonists on CB2, which indicates that bazedoxifene- and lasofoxifene-induced CB2 antagonism is most likely competitive in nature. Our discovery that CB2 is a novel target for bazedoxifene and lasofoxifene suggests that these third-generation SERMs can potentially be repurposed for novel therapeutic indications for which CB2 is a target. In addition, identifying bazedoxifene and lasofoxifene as CB2 inverse agonists also provides important novel mechanisms of actions to explain the known therapeutic effects of these SERMs.


Assuntos
Agonismo Inverso de Drogas , Indóis/farmacologia , Pirrolidinas/farmacologia , Receptor CB2 de Canabinoide/antagonistas & inibidores , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Tetra-Hidronaftalenos/farmacologia , Benzoxazinas/farmacologia , AMP Cíclico/metabolismo , Dronabinol/análogos & derivados , Dronabinol/farmacologia , Células HEK293 , Humanos , Morfolinas/farmacologia , Naftalenos/farmacologia
10.
Cells ; 13(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38994954

RESUMO

Previous research highlighted the involvement of the cannabinoid CB1 receptor in regulating the physiology of hepatocytes and hepatic stellate cells. The inhibition of the CB1 receptor via peripherally restricted CB1 receptor inverse agonist JD5037 has shown promise in inhibiting liver fibrosis in mice treated with CCl4. However, its efficacy in phospholipid transporter-deficiency-induced liver fibrosis remains uncertain. In this study, we investigated the effectiveness of JD5037 in Mdr2-/- mice. Mdr2 (Abcb4) is a mouse ortholog of the human MDR3 (ABCB4) gene encoding for the canalicular phospholipid transporter. Genetic disruption of the Mdr2 gene in mice causes a complete absence of phosphatidylcholine from bile, leading to liver injury and fibrosis. Mdr2-/- mice develop spontaneous fibrosis during growth. JD5037 was orally administered to the mice for four weeks starting at eight weeks of age. Liver fibrosis, bile acid levels, inflammation, and injury were assessed. Additionally, JD5037 was administered to three-week-old mice to evaluate its preventive effects on fibrosis development. Our findings corroborate previous observations regarding global CB1 receptor inverse agonists. Four weeks of JD5037 treatment in eight-week-old Mdr2-/- mice with established fibrosis led to reduced body weight gains. However, contrary to expectations, JD5037 significantly exacerbated liver injury, evidenced by elevated serum ALT and ALP levels and exacerbated liver histology. Notably, JD5037-treated Mdr2-/- mice exhibited significantly heightened serum bile acid levels. Furthermore, JD5037 treatment intensified liver fibrosis, increased fibrogenic gene expression, stimulated ductular reaction, and upregulated hepatic proinflammatory cytokines. Importantly, JD5037 failed to prevent liver fibrosis formation in three-week-old Mdr2-/- mice. In summary, our study reveals the exacerbating effect of JD5037 on liver fibrosis in genetically MDR2-deficient mice. These findings underscore the need for caution in the use of peripherally restricted CB1R inverse agonists for liver fibrosis treatment, particularly in cases of dysfunctional hepatic phospholipid transporter.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 4 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Cirrose Hepática , Receptor CB1 de Canabinoide , Animais , Camundongos , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Receptor CB1 de Canabinoide/agonistas , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/deficiência , Cirrose Hepática/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/metabolismo , Masculino , Camundongos Knockout , Ácidos e Sais Biliares/metabolismo , Agonismo Inverso de Drogas , Camundongos Endogâmicos C57BL
11.
Front Neurosci ; 18: 1359810, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784096

RESUMO

Introduction: The prevalence of Autism Spectrum Disorder (ASD) has drastically risen over the last two decades and is currently estimated to affect 1 in 36 children in the U.S., according to the center for disease control (CDC). This heterogenous neurodevelopmental disorder is characterized by impaired social interactions, communication deficits, and repetitive behaviors plus restricted interest. Autistic individuals also commonly present with a myriad of comorbidities, such as attention deficit hyperactivity disorder, anxiety, and seizures. To date, a pharmacological intervention for the treatment of core autistic symptoms has not been identified. Cannabidiol (CBD), the major nonpsychoactive constituent of Cannabis sativa, is suggested to have multiple therapeutic applications, but its effect(s) on idiopathic autism is unknown. We hypothesized that CBD will effectively attenuate the autism-like behaviors and autism-associated comorbid behaviors in BTBR T+Itpr3tf/J (BTBR) mice, an established mouse model of idiopathic ASD. Methods: Male BTBR mice were injected intraperitoneally with either vehicle, 20 mg/kg CBD or 50 mg/kg CBD daily for two weeks beginning at postnatal day 21 ± 3. On the final treatment day, a battery of behavioral assays were used to evaluate the effects of CBD on the BTBR mice, as compared to age-matched, vehicle-treated C57BL/6 J mice. Results: High dose (50 mg/kg) CBD treatment attenuated the elevated repetitive self-grooming behavior and hyperlocomotion in BTBR mice. The social deficits exhibited by the control BTBR mice were rescued by the 20 mg/kg CBD treatment. Discussion: Our data indicate that different doses for CBD are needed for treating specific ASD-like behaviors. Together, our results suggest that CBD may be an effective drug to ameliorate repetitive/restricted behaviors, social deficits, and autism-associated hyperactivity.

12.
Biochem Biophys Res Commun ; 435(1): 76-81, 2013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23611779

RESUMO

The purpose of the current study was to apply a high throughput assay to systematically screen a library of food and drug administration (FDA)-approved drugs as potential ligands for the cannabinoid receptor 2 (CB2). A cell-based, homogenous time resolved fluorescence (HTRF) method for measuring changes in intracellular cAMP levels was validated and found to be suitable for testing ligands that may act on CB2. Among the 640 FDA-approved drugs screened, raloxifene, a drug used to treat/prevent post-menopausal osteoporosis, was identified for the first time to be a novel CB2 inverse agonist. Our results demonstrated that by acting on CB2, raloxifene enhances forskolin-stimulated cAMP accumulation in a concentration-dependant manner. Furthermore, our data showed that raloxifene competes concentration-dependently for specific [(3)H]CP-55,940 binding to CB2. In addition, raloxifene pretreatment caused a rightward shift of the concentration-response curves of the cannabinoid agonists CP-55,940, HU-210, and WIN55,212-2. Raloxifene antagonism is most likely competitive in nature, as these rightward shifts were parallel and were not associated with any changes in the efficacy of cannabinoid agonists on CB2. Our discovery that raloxfiene is an inverse agonist for CB2 suggests that it might be possible to repurpose this FDA-approved drug for novel therapeutic indications for which CB2 is a target. Furthermore, identifying raloxifene as a CB2 inverse agonist also provides important novel mechanisms of actions to explain the known therapeutic effects of raloxifene.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Cloridrato de Raloxifeno/farmacologia , Receptor CB2 de Canabinoide/agonistas , Benzoxazinas/metabolismo , Benzoxazinas/farmacologia , Ligação Competitiva , Conservadores da Densidade Óssea/metabolismo , Colforsina/farmacologia , AMP Cíclico/metabolismo , Cicloexanóis/metabolismo , Cicloexanóis/farmacologia , Relação Dose-Resposta a Droga , Dronabinol/análogos & derivados , Dronabinol/metabolismo , Dronabinol/farmacologia , Aprovação de Drogas , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Humanos , Morfolinas/metabolismo , Morfolinas/farmacologia , Naftalenos/metabolismo , Naftalenos/farmacologia , Cloridrato de Raloxifeno/metabolismo , Receptor CB2 de Canabinoide/genética , Receptor CB2 de Canabinoide/metabolismo , Transfecção , Trítio , Estados Unidos , United States Food and Drug Administration
13.
Zhongguo Zhong Yao Za Zhi ; 38(17): 2761-7, 2013 Sep.
Artigo em Zh | MEDLINE | ID: mdl-24380294

RESUMO

An ultra performance liquid chromatography (UPLC) method was established and validated to simultaneously determine the contents of six aconitum alkaloids in mother, daughter and fibrous roots of 19 batches of Aconitum carmichaelii from Sichuan province. The separation of the six alkaloids was achieved on a ACQUITY UPLC BEH C18 (2.1 mm x 100 mm, 1.7 microm) column at 40 degrees C with a mobile phase consisting of acetonitrile in 30 mmol x L(-1) ammonium acetate buffer solution (adjusted to pH 10.0 with aqueous ammonia) in gradient mode. The data and plots showed that the six aconitum alkaloids have different distributions. Four aconitum alkaloids were almost same in mother and daughter root except benzoylmesaconine and mesaconitine, while the fibrous root differed from the other two roots. The comparisons of significant differences of six aconitum alkaloids between the mother and daughter roots definitely demonstrated that benzoylmesaconine and mesaconitine were the representative components. The 38 detecting samples were classified as two clusters by hierarchical clustering analysis (HCA) and principle component analysis (PCA), the results indicated that the mother root was different from the daughter root on chemical material basis. The study might contribute to the reasonable clinical application of A. carmichaelii.


Assuntos
Aconitum/química , Alcaloides/análise , Medicamentos de Ervas Chinesas/análise , Aconitum/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento
14.
J Pharm Biomed Anal ; 228: 115324, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36907022

RESUMO

Cannabidiol (CBD) is the most abundant non-psychotropic phytocannabinoid isolated from Cannabis sativa. To support preclinical studies of ocular pharmacology of CBD, a bioanalytical method was developed and validated for quantification of CBD in aqueous humor using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Aqueous humor samples were subjected to protein precipitation by acetonitrile, followed by chromatographic separation using reversed phase LC on a Raptor ARC-18 column with mobile phase A: 0.1 % (v/v) formic acid in water (B) 0.1 % formic acid in acetonitrile (B) as eluents. Detection was carried out with a triple quadrupole mass spectrometer with electrospray ionization operated in positive ion mode. Stable-isotope labeled CBD (CBD-d3) was used as internal standard. The total run time was 8 min. Quantification was accomplished within the validated concentration range of 0.5-500 ng/mL for CBD using a 5 µL sample. The lower limit of quantitation was 0.5 ng/mL. Inter- and intra-day precision is 4.737-7.620 % and 3.426-5.830 %, respectively. Inter- and intra-day accuracy ranged between 99.01 % and 100.2 % and 99.85-101.4 % respectively. The extraction recoveries were found to be 66.06 ± 5.146 %. The established method was successfully applied to investigate ocular pharmacokinetics of CBD in mice. Following intraperitoneal (i.p.) administration of 50 mg/kg CBD, its concentration reaches a Cmax of 71.55 ± 36.64 ng/mL in aqueous humor, with a Tmax of 2 h and a half-life of 1.046 h. The AUC was 183.4 ± 49.17 ng * h/mL. The development and validation of this LC-MS/MS method is an important step toward the goal of assessing the aqueous humor concentrations of CBD and correlating the concentrations of this phytocannabinoid with its ocular pharmacologic effects.


Assuntos
Canabidiol , Canabinoides , Camundongos , Animais , Cromatografia Líquida/métodos , Canabinoides/análise , Canabidiol/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Humor Aquoso/metabolismo , Reprodutibilidade dos Testes
15.
Mol Vis ; 18: 2839-46, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23233786

RESUMO

PURPOSE: To examine the interaction of heat shock protein 90 (Hsp90) with the CB2 cannabinoid receptor in trabecular meshwork (TM) cells and to investigate the roles of Hsp90 in CB2 receptor-mediated cell signaling and actin cytoskeleton remodeling. METHODS: Coimmunoprecipitation experiments and western blot analyses, using specific anti-CB2 and anti-Hsp90 antibodies, were performed to study the interaction of Hsp90 with the CB2 receptor in TM cells. An antiphospho-extracellular-signal-regulated kinases 1/2 (ERK1/2) antibody was used to detect the CB2 receptor-mediated phosphrylation of ERK1/2. In cytoskeleton studies, Alexa Fluor 488-labeled phalloidin staining was used to examine actin filaments of TM cells. PD98059, a specific inhibitor of the ERK1/2 pathway, was used to evaluate the role ERK1/2 pathway in CB2 receptor-mediated actin cytoskeleton changes. Geldanamycin, an inhibitor of Hsp90, was used to investigate the roles of Hsp90 in CB2 receptor-mediated ERK1/2 phosphorylation and actin cytoskeleton remodeling. RESULTS: The interaction of Hsp90 with the CB2 receptor was established in TM cells with coimmunoprecipitation experiments and western blot analyses. Treatment of TM cells with geldanamycin significantly inhibited the interaction of Hsp90 with the CB2 receptor. Disruption of the CB2/Hsp90 interaction by treating TM cells with geldanamycin inhibited CB2 receptor-mediated ERK1/2 phosphorylation, as well as actin cytoskeleton remodeling. Furthermore, treatment of TM cells with PD98059 profoundly attenuated CB2 receptor-mediated actin cytoskeleton changes. CONCLUSIONS: The data from this study establish a specific interaction between Hsp90 and the CB2 receptor in TM cells. In addition, the current study demonstrates that by interacting with the CB2 receptor, Hsp90 plays an important role as a molecular chaperone in CB2 receptor-mediated cell signaling and actin cytoskeleton rearrangement in TM cells.


Assuntos
Proteínas de Choque Térmico HSP90/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Malha Trabecular/metabolismo , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Animais , Benzoquinonas/farmacologia , Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/genética , Imunoprecipitação , Lactamas Macrocíclicas/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/genética , Fosforilação , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Receptor CB2 de Canabinoide/genética , Transdução de Sinais/efeitos dos fármacos , Suínos , Técnicas de Cultura de Tecidos , Malha Trabecular/citologia , Malha Trabecular/efeitos dos fármacos
16.
Exp Eye Res ; 100: 59-64, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22580290

RESUMO

The purpose of this study was to investigate the effects of abnormal-cannabidiol (abn-cbd), a non-psychoactive cannabinoid agonist, on aqueous humor outflow via the trabecular meshwork (TM) of porcine eye, and to examine the involvement of a non-CB1/CB2 cannabinoid receptor and the p42/44 mitogen-activated protein kinase (p42/44 MAPK) pathway. The effects of abn-cbd on aqueous humor outflow were measured using a porcine anterior segment perfused organ culture model. The activation of p42/44 MAPK by abn-cbd was determined in cultured TM cells with western blot analysis using an anti-phospho-p42/44 MAPK antibody. Administration of abn-cbd caused a concentration-dependent enhancement of aqueous humor outflow facility with a maximum effect (155.0 ± 11.7% of basal outflow facility) after administration of 30 nM abn-cbd. Pretreatment with 1 µM of O-1918, a cannabidiol analog that acts as a selective antagonist at the non-CB1/CB2 receptor, produced a full antagonism of 30 nM abn-cbd induced increase of aqueous humor outflow facility. Pretreatment with 1 µM of CB1 antagonist SR141716A partially blocked, whereas pretreatment with either 1 µM of CB1 antagonist AM251 or 1 µM of CB2 antagonist SR144528 had no effect on abn-cbd induced enhancement of outflow facility. Treatment of TM cells with 30 nM of abn-cbd activated p42/44 MAPK, which was blocked completely by pretreatment with O-1918, and partially by pretreatment with SR141716A, but not by either AM251 or SR144528. In addition, PD98059, an inhibitor of p42/44 MAPK pathway, blocked completely the abn-cbd induced p42/44 MAPK activation and blocked partially the abn-cbd induced enhancement of outflow facility. In conclusion, the results from this study demonstrate that abn-cbd increases aqueous humor outflow through the TM pathway of the eye, and this effect is mediated by a non-CB1/CB2 cannabinoid receptor, with an involvement of p42/44 MAPK signaling pathway.


Assuntos
Humor Aquoso/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Resorcinóis/farmacologia , Malha Trabecular/efeitos dos fármacos , Animais , Anisóis/farmacologia , Western Blotting , Canabinoides/antagonistas & inibidores , Células Cultivadas , Cicloexanos/farmacologia , Relação Dose-Resposta a Droga , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Técnicas de Cultura de Órgãos , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/antagonistas & inibidores , Rimonabanto , Suínos , Malha Trabecular/metabolismo
17.
Zhongguo Zhong Yao Za Zhi ; 37(17): 2530-3, 2012 Sep.
Artigo em Zh | MEDLINE | ID: mdl-23236745

RESUMO

OBJECTIVE: To analyze ginsenosides composition in wild ginseng leaves with different growth years. METHOD: The analysis was performed on Acquity UPLC BEH Shield RP18 (2.1 mm x 100 mm, 1.7 microm) column, the mobile phase was acetonitrile-0.05% formic acid solution in gradient elution mode. The detection wavelength was at 203 nm. The flow rate was 0.4 mL x min(-1) and column temperature was set at 30 degrees C. RESULT: Thirteen ginsenosides were determined by the established UPLC method. In 5-17th growth year ginseng leaf samples cultivated simulating wild conditions, the contents of ginsenosides in the 14th year have the highest content. CONCLUSION: The established method is simple, accurate and reliable, can be used in ginsenosides determination and fingerprint research of Panax crude drug. The result provides reliable data for the accumulation of ginsenosides and sustainable utilization of ginseng resources.


Assuntos
Medicamentos de Ervas Chinesas/análise , Ginsenosídeos/análise , Panax/química , Folhas de Planta/química , Panax/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Fatores de Tempo
18.
Cells ; 11(19)2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36230968

RESUMO

Intraocular pressure (IOP) is regulated primarily through aqueous humor production by ciliary body and drainage through uveoscleral and trabecular meshwork (TM) tissues. The goal of this study was to measure the effect of non-psychotropic cannabidiol (CBD) on aqueous humor outflow through TM and assess the effect of CBD on the TM cell signaling pathways that are important for regulating outflow. Perfused porcine eye anterior segment explants were used to investigate the effects of CBD on aqueous humor outflow. Cultured porcine TM cells were used to study the effects of CBD on TM cell contractility, myosin light chain (MLC) and myosin phosphatase targeting subunit 1 (MYPT1) phosphorylation, and RhoA activation. In the anterior segment perfusion experiments, aqueous humor outflow was increased significantly within 1 h after adding 1 µM CBD and the effect was sustained over the 5 h of measurement. Treatment of TM cells with 1 µM CBD significantly decreased TM cell-mediated collagen contraction, inhibited phosphorylation of MLC and MYPT1, and reduced RhoA activation. Our data demonstrate, for the first time, that as a potential therapeutic agent for lowering intraocular pressure, CBD can enhance aqueous humor outflow and modify TM cell signaling.


Assuntos
Canabidiol , Malha Trabecular , Animais , Humor Aquoso/metabolismo , Canabidiol/farmacologia , Cadeias Leves de Miosina/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/farmacologia , Transdução de Sinais , Suínos , Malha Trabecular/metabolismo
19.
Mol Med Rep ; 25(5)2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35315494

RESUMO

Previous studies have indicated that chronic intermittent hypobaric hypoxia (CIHH) preconditioning can inhibit TNF­α and other related inflammatory cytokines and exerts protective effect on intervertebral disc degeneration disease (IDD) in rats; however, the mechanism is still unclear. The present study aimed to explore the repair mechanisms of CIHH on IDD in rats. In the experiment, 48 adult Sprague­Dawley rats were selected and randomly divided into an experimental group (CIHH­IDD), a degenerative group (IDD) and a control group (CON). The CIHH­IDD group of rats (n=16) were treated with CIHH (simulated 3000 m altitude, 5 h per day, 28 days; PO2=108.8 mmHg) before disc degeneration surgery. The IDD group of rats (n=16) underwent tail­vertebral intervertebral disc surgery to establish a model of intervertebral disc degeneration. The CON group of rats (n=16) did not receive any treatments. After surgery, the disc height index was calculated using X­ray analysis of rat tail vertebrae, the degeneration process was observed and repair was evaluated by chemically staining degenerative intervertebral disc tissue slices. The expression levels of basic fibroblast growth factor (bFGF), TGFß1, Collagen I and Collagen II were measured in the intervertebral disc tissue using western blotting; while the expression levels of bFGF, TGFß1 and hypoxia­inducible factor 1­α (HIF­1α) were measured in rat serum using ELISA. The results demonstrated that: i) The degree of intervertebral disc height degeneration in CIHH­IDD rats was significantly lower compared with that in IDD rats (P<0.05); ii) the expression levels of bFGF, TGFß1 and HIF­1α were higher in CIHH­IDD rat serum compared with those in IDD rat serum (P<0.05); iii) optical microscopy revealed that the degree of disc degeneration was relatively mild in CIHH­IDD rats; and iv) the protein expression levels of bFGF, TGFß1 and collagen II were increased in CIHH­IDD rat intervertebral disc tissues compared with those of IDD rats, while the overexpression of collagen I protein was inhibited. Overall, after CIHH pre­treatment, the expression levels of bFGF and TGFß1 were up­regulated, which play notable roles in repairing degenerative intervertebral discs in rats.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Animais , Colágeno/metabolismo , Hipóxia/metabolismo , Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/terapia , Ratos , Ratos Sprague-Dawley
20.
Cell Rep ; 41(1): 111452, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36198275

RESUMO

Epithelial-mesenchymal transition (EMT) facilitates cancer invasion and is initiated by mesenchyme-driving transcription factors and actin cytoskeletal assembly. We show a cytoplasmic-to-nuclear transport gradient of the EMT transcription factor Zeb1 toward sites of invasion in lung adenocarcinoma (LUAD), driven by the EMT inducer Tgfb, which is expressed in M2 polarized macrophages. We show that Zeb1 binds free actin monomers and RhoA in the cytoplasm to inhibit actin polymerization, blocking cell migration and Yap1 nuclear transport. Tgfb causes turnover of the scaffold protein Rassf1a, which targets RhoA. Release of this RhoA inhibition in response to Tgfb overcomes Zeb1's block of cytoskeleton assembly and frees it for nuclear transport. A ZEB1 nuclear transport signature highlights EMT progression, identifies dedifferentiated invasive/metastatic human LUADs, and predicts survival. Blocking Zeb1 nuclear transport with a small molecule identified in this study inhibits cytoskeleton assembly, cell migration, Yap1 nuclear transport, EMT, and precancerous-to-malignant transition.


Assuntos
Neoplasias Pulmonares , Homeobox 1 de Ligação a E-box em Dedo de Zinco , Actinas/metabolismo , Linhagem Celular Tumoral , Citoesqueleto/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Humanos , Neoplasias Pulmonares/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
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