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1.
BMC Med Genet ; 18(1): 19, 2017 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-28231849

RESUMO

BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare disorder characterized by multiple gastrointestinal hamartomatous polyps and mucocutaneous pigmentation. STK11 has been identified as a causative gene for this disease. CASE PRESENTATION: Herein we report a Chinese Han kindred with PJS. Onset for the PJS signs in three of the patients was rarely as early as at birth. We identified a novel heterozygous mutation (c.440_441delGT, p.Arg147Leufs*15) in the gene STK11, causing a short frameshift followed by a deletion of 63% of the amino acids in the STK protein. This mutation co-segregated with the PJS phenotype, and was absent in two hundred of unrelated ethnicity-matched controls. The mutation led to expression decrease of unaffected STK11 protein in patients than in controls, as well in PJ polyps than in circulating leucocytes from the patients. Phosphorylation levels of the downstream kinase AMPKα altered according with the expression of STK11. These results indicated the possibility that haploinsufficiency and epigenetic reduction of STK11 contributed to the pathogenesis of the disease. CONCLUSION: This study identifies a novel mutation in the pathogenic gene STK11 leading to PJS.


Assuntos
Mutação em Linhagem Germinativa , Síndrome de Peutz-Jeghers/genética , Proteínas Serina-Treonina Quinases/genética , Quinases Proteína-Quinases Ativadas por AMP , Adolescente , Sequência de Bases , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , Éxons , Mutação da Fase de Leitura , Heterozigoto , Humanos , Masculino , Linhagem , Síndrome de Peutz-Jeghers/diagnóstico , Síndrome de Peutz-Jeghers/patologia , Análise de Sequência de DNA
2.
Mediators Inflamm ; 2015: 726243, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26273142

RESUMO

Acute kidney injury associated with renal hypoperfusion is a frequent and severe complication during sepsis. Fluid resuscitation is the main therapy. However, heart failure is usually lethal for those patients receiving large volumes of fluids. We compared the effects of small-volume resuscitation using four different treatment regimens, involving saline, hypertonic saline (HTS), hydroxyethyl starch (HES), or hypertonic saline hydroxyethyl starch (HSH), on the kidneys of rats treated with lipopolysaccharide (LPS) to induce endotoxemia. LPS injection caused reduced and progressively deteriorated systemic (arterial blood pressure) and renal hemodynamics (renal blood flow and renal vascular resistance index) over time. This deterioration was accompanied by marked renal functional and pathological injury, as well as an oxidative and inflammatory response, manifesting as increased levels of tumor necrosis factor-α, nitric oxide, and malondialdehyde and decreased activity of superoxide dismutase. Small-volume perfusion with saline failed to improve renal and systemic circulation. However, small-volume perfusion with HES and HSH greatly improved the above parameters, while HTS only transiently improved systemic and renal hemodynamics with obvious renal injury. Therefore, single small-volume resuscitation with HES and HSH could be valid therapeutic approaches to ameliorate kidney injury induced by endotoxemia, while HTS transiently delays injury and saline shows no protective effects.


Assuntos
Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Endotoxemia/complicações , Hidratação/métodos , Derivados de Hidroxietil Amido/uso terapêutico , Animais , Endotoxemia/induzido quimicamente , Lipopolissacarídeos/toxicidade , Masculino , Ratos , Ratos Sprague-Dawley , Solução Salina Hipertônica/uso terapêutico
3.
Circ Res ; 111(9): 1137-46, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-22896586

RESUMO

RATIONALE: Angiotensin II (Ang II) has pleiotropic effects on vascular smooth muscle cells (VSMCs). It has been demonstrated to promote the proliferative phenotype of VSMCs in mouse ascending aorta, but the underlying mechanisms remain incompletely understood. OBJECTIVE: The present study was designed to explore whether the Ca(2+)-permeable transient receptor potential melastatin 7 (TRPM7) channel is involved in Ang II-induced phenotype switching of ascending aortic VSMCs and to dissect the molecular mechanisms by which TRPM7 modulates VSMC phenotype. METHODS AND RESULTS: As revealed by current recording, Ang II infusion increased TRPM7 whole-cell currents in ascending aortic VSMCs. The increase in TRPM7 currents was found to result from enhanced expression of TRPM7 protein rather than elevated single-channel activity (open probability and slope conductance) and/or reduced Mg(2+)-mediated channel block. Mechanistically, Ang II elevated TRPM7 expression via Ang II type 1 receptor-mediated ERK1/2 signaling. As indicated by the expression levels of VSMC differentiation marker genes, phenotypic switching of ascending aorta occurred during Ang II infusion. Meanwhile, ERK1/2-Elk-1 signaling pathway known to suppress VSMC differentiation was activated in Ang II-infused ascending aorta. Knockdown of TRPM7 with small interfering RNA established a causative role of TRPM7 in Ang II-induced phenotypic change and promotion of cell proliferation. Moreover, TRPM7 was shown to be required for Pyk2-ERK1/2-Elk-1 pathway activation by Ang II, which potentiated TRPM7 channel function and thus activated the Ca(2+)-sensitive kinase Pyk2. Finally, TRPM7 knockdown attenuated Ang II-induced displacement of myocardin from SM22 promoter, but the effects could be reversed by expression of constitutively active c-Src. CONCLUSIONS: Our data establish that upregulation of TRPM7 channels by Ang II contributes to the development of the proliferative phenotype of ascending aortic VSMCs, and TRPM7 channel suppresses VSMC gene expression via Ca(2+) influx-mediated activation of Pyk2-ERK1/2-Elk-1 pathway.


Assuntos
Angiotensina II/farmacologia , Diferenciação Celular/efeitos dos fármacos , Músculo Liso Vascular/citologia , Canais de Cátion TRPM/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Aorta/citologia , Aorta/efeitos dos fármacos , Diferenciação Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quinase 2 de Adesão Focal/efeitos dos fármacos , Quinase 2 de Adesão Focal/fisiologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Músculo Liso Vascular/efeitos dos fármacos , Fenótipo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia , Proteínas Elk-1 do Domínio ets/efeitos dos fármacos , Proteínas Elk-1 do Domínio ets/fisiologia
4.
ChemSusChem ; : e202401568, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327838

RESUMO

The encapsulation of protein enzymes in metal-organic frameworks (MOFs) has been recognized as an effective enzyme immobilization approach. In this study, we demonstrated the influence of enzyme amount and the isoelectric points (pI) of different enzymes on the enzyme loading capacity in both mechanochemical (ball-milling) and water-based approaches. We found that increasing enzyme amounts enhances MOF enzyme loading without compromising activity, while the MOF shell protects encapsulated enzymes from proteinase K degradation through its size-sheltering mechanism. However, an excess of enzymes can hinder the formation of ZIF-90. Moreover, enzymes with low pI values (e.g., catalase, pI 5.4) facilitate encapsulation in MOFs, whereas enzymes with high pI values (e.g., lysozyme, pI 11.35) are more challenging to encapsulate. The simulation results revealed that increasing the enzyme amounts and pI values raises the activation energy necessary for MOF formation. This study highlights the crucial role of enzyme properties in the encapsulation process within MOFs, providing valuable insights for fabricating enzyme-MOF biocomposites for diverse applications, such as protein drug delivery.

5.
Pain Physician ; 26(5): 485-493, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37774187

RESUMO

BACKGROUND: Post-dural puncture headache (PDPH) is particularly likely to happen in patients under obstetric care due to an unintentional dural puncture (UDP). There is as yet no ideal strategy for preventing UDP-induced PDPH. OBJECTIVES: The primary objective of this study was to assess whether a prophylactic epidural blood patch (EBP) or prophylactic epidural infusion of hydroxyethyl starch (HES) is effective in preventing PDPH for parturients with UDP compared with conservative treatments. STUDY DESIGN: Retrospective analysis from a single center's inpatient data. SETTING: Department of Anesthesiology at a single center. METHODS: A retrospective study was conducted of a single center's inpatient data from January 2017 through March 2020. The study included parturients with UDP during neuraxial anesthesia. The interventions of UDP included conservative treatment, prophylactic EBP, and prophylactic epidural infusion of HES. The incidence of PDPH, the use of intravenous aminophylline, therapeutic EBP, symptom onset, duration of headache, and duration of hospital stay were compared. RESULTS: A total of 85 patients were analyzed. The incidences of PDPH were 84%, 52.6% and 54.5% with conservative, prophylactic EBP, and prophylactic epidural HES treatments, respectively. Compared with the conservative treatment, prophylactic EBP and prophylactic epidural HES treatment significantly reduced the incidence of PDPH (P < 0.05). No significant difference was found between the prophylactic EBP and prophylactic epidural HES groups. Compared with the conservative treatment group, therapeutic EBP was significantly less used in the prophylactic EBP and prophylactic epidural HES groups (P < 0.05). Prophylactic EBP shortened the length of hospital stay of parturients with UDP (P < 0.05) while prophylactic epidural HES showed no statistical difference compared with conservative treatment. No severe complications, such as central nervous system and puncture site infection or nerve injury, were found in those patients. LIMITATIONS: Retrospective nature and single center data with a relatively small sample size. CONCLUSIONS: Prophylactic management with EBP and epidural infusion of HES has an effect in preventing the occurrence of PDPH; prophylactic EBP significantly shortened hospital stay length in parturients with UDP. KEY WORDS: Unintentional dural puncture, epidural blood patch, hydroxyethyl starch, post-dural puncture headache, parturient.


Assuntos
Cefaleia Pós-Punção Dural , Gravidez , Feminino , Humanos , Cefaleia Pós-Punção Dural/prevenção & controle , Estudos Retrospectivos , Placa de Sangue Epidural , Amido , Difosfato de Uridina
6.
World J Clin Oncol ; 13(10): 789-801, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36337314

RESUMO

BACKGROUND: Natural orifice specimen extraction (NOSE) via the anus or vagina replaces conventional transabdominal specimen retrieval via the transabdominal route through a limited mid-line laparotomy or Pfannenstiel incision. Reducing the number of laparoscopic ports further decreases operative abdominal wall trauma. These techniques reduce the surgical wound size as well as the risk of incision-related morbidity. AIM: To compare short-term outcomes following 3-port NOSE surgery with a matched cohort of conventional non-NOSE colorectal cancer surgery. METHODS: Patients who underwent elective 3-port laparoscopic colorectal NOSE surgery between February to October 2021 were identified. Selection criteria for NOSE surgery was adapted from the 2019 International Consensus on Natural Orifice Specimen Extraction Surgery for colorectal cancer. Patients with clinical T4 or N2 tumors on staging computed tomography were also excluded. The propensity score-matched cohort was identified amongst patients who underwent conventional laparoscopic colorectal surgery from January 2019 to December 2020. Matching was performed in the ratio of 1:4 based on age, gender, type of resection, and p - tumor node metastasis staging. RESULTS: Over the eight-month study duration, 14 consecutive cases (nine female, five male) of elective 3-port laparoscopic surgery with NOSE were performed for colorectal cancer. Median age and body mass index were 70 (range 43-82) years and 24.1 (range 20.0-31.7) kg/m2 respectively. Six patients underwent transanal NOSE and eight had transvaginal NOSE. Median operative time, intraoperative blood loss and postoperative length of stay were 208 (range 165-365) min, 30 (range 10-150) mL and 3 (range 2-6) d respectively. Two (14%) suffered minor postoperative compilations not attributable to the NOSE procedure. Median follow-up duration was 12 (range 8-15) mo. No instances of mortality, local or distant disease recurrence were recorded in this cohort. Compared to the conventional surgery cohort of 56 patients, the 3-port NOSE cohort had significantly quicker mean return of bowel function (2.6 vs 1.2 d, P < 0.001), reduced postoperative pain and patient-controlled analgesia use, and decreased length of hospital stay (6.4 vs 3.4 d, P < 0.001). There were no statistical differences in surgical duration and perioperative complication rates between the NOSE and non-NOSE cohorts. CONCLUSION: 3-port laparoscopic colorectal surgery with NOSE is a feasible technique, augmenting the minimally invasive nature of surgery and producing good outcomes. Appropriate patient selection and expertise in conventional laparoscopy are required.

7.
Cardiovasc Res ; 109(1): 34-43, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26598506

RESUMO

AIMS: Ionic perturbation in vascular smooth muscle cells contributes to cerebrovascular remodelling in the setting of hypertension, but the role of transient receptor potential (TRP) channel superfamily remains unknown. The present study was conducted to define the contribution of TRP channels to cerebrovascular remodelling. METHODS AND RESULTS: By integrating quantitative PCR, western blotting, patch clamping, and Ca(2+) imaging, we identified TRP channel, subfamily canonical, member 3 (TRPC3) as the channel subtype most considerably elevated in basilar arteries of two-kidney, two-clip stroke-prone hypertensive rats. Importantly, administration of pyrazole 3 (Pyr3), a TRPC3 channel blocker, attenuated cerebrovascular remodelling. During hypertension, epidermal growth factor receptor (EGFR) was transactivated, as evidenced by marked EGFR phosphorylation, increased pro-HB-EGF shedding, and elevated activity of ADAM17 (HB-EGF sheddase). ADAM17 activity was increased owing to enhanced activation rather than elevated expression. Remarkably, Pyr3 treatment suppressed EGFR transactivation in hypertension. In proliferating basilar artery smooth muscle cells or basilar arteries of hypertensive rats, co-immunoprecipitation assay revealed an interaction between TRPC3 and ADAM17 upon Ang II stimulation. CONCLUSION: Collectively, we demonstrated that enhanced EGFR transactivation, due to increased TRPC3 expression and functional coupling of TRPC3/ADAM17, resulted in cerebrovascular remodelling. Therefore, TRPC3-induced EGFR transactivation may be therapeutically exploited to prevent hypertension-induced cerebrovascular remodelling.


Assuntos
Encéfalo/irrigação sanguínea , Receptores ErbB/fisiologia , Hipertensão/patologia , Transdução de Sinais/fisiologia , Canais de Cátion TRPC/fisiologia , Ativação Transcricional , Remodelação Vascular , Proteínas ADAM/fisiologia , Proteína ADAM17 , Animais , Sinalização do Cálcio , Miócitos de Músculo Liso/fisiologia , Ratos , Canais de Cátion TRPC/antagonistas & inibidores
8.
Int J Clin Exp Pathol ; 8(9): 10752-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26617786

RESUMO

Sepsis induces hepatic injury but whether alpha-2 adrenoceptor (α2-AR) modulates the severity of sepsis-induced liver damage remains unclear. The present study used lipopolysaccharide (LPS) to induce hepatic injury and applied α2-AR agonist dexmedetomidine (DEX) and/or antagonist yohimbine to investigate the contribution of α2-AR in LPS-induced liver injury. Our results showed that LPS resulted in histological and functional abnormality of liver tissue (ALT and AST transaminases, lactate), higher mortality, an increase in proinflammatory cytokines (IL-1ß, IL-6 & TNF-α), as well as a change in oxidative stress (MDA, SOD). Activation of α2-AR by dexmedetomidine (DEX) attenuated LPS-induced deleterious effects on the liver and block of α2-AR by yohimbine aggravated LPS-induced liver damage. Our data suggest that α2-AR plays an important role in sepsis-induced liver damage and activation of α2-AR with DEX could be a novel therapeutic avenue to protect the liver against sepsis-induced injury.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Dexmedetomidina/farmacologia , Lipopolissacarídeos , Fígado/efeitos dos fármacos , Receptores Adrenérgicos beta 2/efeitos dos fármacos , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citoproteção , Modelos Animais de Doenças , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Ácido Láctico/sangue , Fígado/metabolismo , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta 2/metabolismo , Sepse/induzido quimicamente , Superóxido Dismutase/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Ioimbina/farmacologia
9.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 21(2): 144-8, 2004 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15079797

RESUMO

OBJECTIVE: To study the genetic polymorphisms of the mitochondrial DNA (mtDNA) control region in Chengdu Han population. METHODS: Sequence polymorphisms of the mtDNA control region, hypervariable regions I and II from 100 unrelated Chinese Hans were determined by PCR and direct sequencing. RESULTS: Sequences of 404 nucleotides for hypervariable region I and 379 nucleotides for region II were obtained. Ninety-two and fifty variable sites were revealed in region I and region II respectively as compared to the reference sequence, and a total of 97 different genetic patterns from both the regions I and II were determined. The probability of identity was estimated at 1.84% for region I, 1.94% for region II, and 1.18% for both the regions. CONCLUSION: These results suggest that sequence polymorphism of mtDNA control region would be very useful in forensic practice as a marker for individual identification.


Assuntos
DNA Mitocondrial/química , Polimorfismo Genético , Sequência de Bases , China , Genética Populacional , Humanos , Dados de Sequência Molecular , Mutação
10.
Cell Transplant ; 22(12): 2219-36, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23295060

RESUMO

Oligodendrocyte (OL) replacement can be a promising strategy for spinal cord injury (SCI) repair. However, the poor posttransplantation survival and inhibitory properties to axonal regeneration are two major challenges that limit their use as donor cells for repair of CNS injuries. Therefore, strategies aimed at enhancing the survival of grafted oligodendrocytes as well as reducing their inhibitory properties, such as the use of more permissive oligodendrocyte progenitor cells (OPCs), also called glial restricted precursor cells (GRPs), should be highly prioritized. Schwann cell (SC) transplantation is a promising translational strategy to promote axonal regeneration after CNS injuries, partly due to their expression and secretion of multiple growth-promoting factors. Whether grafted SCs have any effect on the biological properties of grafted GRPs remains unclear. Here we report that either SCs or SC-conditioned medium (SCM) promoted the survival, proliferation, and migration of GRPs in vitro. When GRPs and SCs were cografted into the normal or injured spinal cord, robust survival, proliferation, and migration of grafted GRPs were observed. Importantly, grafted GRPs differentiated into mature oligodendrocytes and formed new myelin on axons caudal to the injury. Finally, cografts of GRPs and SCs promoted recovery of function following SCI. We conclude that cotransplantation of GRPs and SCs, the only two kinds of myelin-forming cells in the nervous system, act complementarily and synergistically to promote greater anatomical and functional recovery after SCI than when either cell type is used alone.


Assuntos
Células de Schwann/transplante , Traumatismos da Medula Espinal/cirurgia , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Axônios/fisiologia , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Meios de Cultivo Condicionados/farmacologia , Feminino , Membro Posterior/fisiologia , Atividade Motora , Bainha de Mielina/metabolismo , Oligodendroglia/citologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Regeneração , Células de Schwann/citologia , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia
11.
Ying Yong Sheng Tai Xue Bao ; 22(7): 1810-6, 2011 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-22007459

RESUMO

Based on the X-Ray fluorescence spectroscopic measurement of heavy metals concentration in roadside soil samples from Xi' an City, and by the methods of principal component analysis, cluster analysis, and correlation analysis, this paper approached the possible sources of heavy metals in the roadside soils of the City. In the meantime, potential ecological risk index was used to assess the ecological risk of the heavy metals. In the roadside soils, the mean concentrations of Co, Cr, Cu, Mn, Ni, Pb, and Zn were higher than those of the Shaanxi soil background values. The As, Mn and Ni in roadside soils mainly came from natural source and transportation source, the Cu, Pb, and Zn mainly came from transportation source, and the Co and Cr mainly came from industry source. These heavy metals in the roadside soils belonged to medium pollution, and had medium potential ecological risk.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Solo/análise , China , Cidades , Resíduos Industriais/análise , Medição de Risco , Emissões de Veículos/análise
12.
Hypertension ; 56(3): 445-52, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20644009

RESUMO

Statins have pleiotropic actions against the development of vascular remodeling and the incidence of ischemic stroke. Although previous studies have suggested that posttranslational modification of several proteins, such as Rho by mevalonate-derived isoprene groups, geranylgeranyl pyrophosphate or farnesyl pyrophosphate, underlie the pleiotropic effects of statins, the detailed mechanisms remain elusive. Recent growing evidence demonstrated that ClC-3 volume-regulated chloride channel plays an important role in cell proliferation, and the activity of this channel is increased in basilar smooth muscle cells from a hypertensive rat. We hypothesized that inhibition of volume-regulated chloride channel may contribute to the beneficial effects of statins on cerebrovascular remodeling during hypertension. Our study here demonstrated that simvastatin ameliorated hypertension-caused cerebrovascular remodeling. In rat basilar smooth muscle cells, simvastatin inhibited cell proliferation and activation of volume-regulated chloride channel, and these effects of simvastatin were abolished by pretreatment with mevalonate or geranylgeranyl pyrophosphate. In addition, Rho A inhibitor C3 exoenzyme and Rho kinase inhibitor Y-27632 both reduced cell proliferation and activation of volume-regulated chloride channel. Moreover, ClC-3 overexpression decreased the suppressive effect of simvastatin on cell proliferation and increased estimated IC(50) of simvastatin on endothelin 1- and hypo-osmolarity-induced cell proliferation from 3.40+/-0.08 and 3.50+/-0.10 micromol/L to 5.30+/-0.70 and 5.60+/-0.70 micromol/L, respectively (P<0.01; n=6). Furthermore, the expression of ClC-3 was increased in basilar artery during hypertension, and simvastatin normalized the upregulation of ClC-3. Our data suggested that simvastatin ameliorates cerebrovascular remodeling in the hypertensive rat through inhibition of vascular smooth muscle cell proliferation by suppression of volume-regulated chloride channel.


Assuntos
Circulação Cerebrovascular/efeitos dos fármacos , Canais de Cloreto/metabolismo , Hipertensão/tratamento farmacológico , Miócitos de Músculo Liso/efeitos dos fármacos , Sinvastatina/farmacologia , Análise de Variância , Animais , Western Blotting , Proliferação de Células/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipertensão/metabolismo , Ácido Mevalônico/farmacologia , Miócitos de Músculo Liso/metabolismo , Fosfatos de Poli-Isoprenil/farmacologia , Ratos , Sinvastatina/uso terapêutico , Quinases Associadas a rho/metabolismo
13.
Eur J Pharmacol ; 606(1-3): 142-9, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19374845

RESUMO

The total saponins of Panax notoginseng have been clinically used for the treatment of cardiovascular diseases and stroke in China. Our recent study has identified ginsenoside-Rd, a purified component of total saponins of P. notoginseng, as an inhibitor to remarkably inhibit voltage-independent Ca(2+) entry. We deduced a hypothesis that the inhibition of voltage-independent Ca(2+) entry might contribute to its cerebrovascular benefits. Ginsenoside-Rd was administered to two-kidney, two-clip (2k2c) stroke-prone hypertensive rats to examine its effects on blood pressure, cerebrovascular remodeling and Ca(2+) entry in freshly isolated basilar arterial vascular smooth muscle cells (BAVSMCs). Its effects on endothelin-1 induced Ca(2+) entry and cellular proliferation were assessed in cultured BAVSMCs. The results showed that, in vivo, ginsenoside-Rd treatment attenuated basilar hypertrophic inward remodeling in 2k2c hypertensive rats without affecting systemic blood pressure.During the development of hypertension, there were time-dependent increases in receptor-operated Ca(2+) channel (ROCC)-, store-operated Ca(2+) channel (SOCC)- and voltage dependent Ca(2+) channel (VDCC)-mediated Ca(2+) entries in freshly isolated BAVSMCs. Ginsenoside-Rd reversed the increase in SOCC- or ROCC- but not VDCC-mediated Ca(2+) entry. In vitro, ginsenoside-Rd concentration-dependently inhibited endothelin-1 induced BAVSMC proliferation and Mn(2+) quenching rate within the same concentration range as required for inhibition of increased SOCC- or ROCC-mediated Ca(2+) entries during hypertension. These results provide in vivo evidence showing attenuation of hypertensive cerebrovascular remodeling after ginsenoside-Rd treatment. The underlying mechanism might be associated with inhibitory effects of ginsenoside-Rd on voltage-independent Ca(2+) entry and BAVSMC proliferation, but not with VDCC-mediated Ca(2+) entry.


Assuntos
Artéria Basilar/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Cálcio/metabolismo , Condutividade Elétrica , Ginsenosídeos/farmacologia , Hipertensão Renovascular/fisiopatologia , Acidente Vascular Cerebral/etiologia , Animais , Artéria Basilar/metabolismo , Artéria Basilar/fisiopatologia , Artéria Basilar/ultraestrutura , Pressão Sanguínea/efeitos dos fármacos , Encéfalo/irrigação sanguínea , Proliferação de Células/efeitos dos fármacos , Endotelina-1/farmacologia , Hipertensão Renovascular/complicações , Hipertensão Renovascular/metabolismo , Hipertensão Renovascular/patologia , Masculino , Microscopia Eletrônica de Transmissão , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Ratos , Ratos Sprague-Dawley
14.
Hypertension ; 49(6): 1371-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17438308

RESUMO

The cerebrovascular remodeling is a prominent feature of hypertension and considered a major risk factor for stroke. Cerebrovascular smooth muscle cells meet volume challenge during this pathophysiological process. Our previous studies suggest that volume regulated chloride channels may be critical to the cell cycle of vascular smooth muscle cells. However, it is unknown whether the volume-regulated chloride movement is altered in hypertension. Therefore, we directly measured the concentration of intracellular chloride ([Cl(-)](i)) in rat basilar arterial smooth muscle cells isolated from control rats and rats that were made hypertensive for 1 to 12 weeks after partial renal artery constriction (2-kidney, 2-clip method) using a 6-methoxy-N-ethylquinolinium iodide fluorescence probe. The [Cl(-)](i) in isotonic solution showed no difference in all of the groups. After hypotonic perfusion, the reduction in [Cl(-)](i) was more prominent in hypertensive cerebrovascular smooth muscle cells than in sham control cells. Genistein, a protein tyrosine kinase inhibitor, inhibited hypotonic-induced reduction in [Cl(-)](i), whereas sodium orthovanadate, a protein-tyrosine phosphatase inhibitor, enhanced hypotonic-induced reduction in [Cl(-)](i) in both groups. The percentage inhibition of reduction in [Cl(-)](i) by genistein on volume-regulated chloride movement has a positive correlation with blood pressure levels in the 2-kidney, 2-clip hypertensive group, as is the case for the percentage increase of reduction in [Cl(-)](i) by sodium orthovanadate. Antihypertensive therapy with the angiotensin-converting enzyme inhibitor captopril completely reversed abnormal volume-regulated chloride movement in hypertensive rats. We conclude that volume-regulated chloride movement is augmented in rat cerebrovascular smooth muscle cells in proportion to the severity of hypertension.


Assuntos
Artérias Cerebrais/metabolismo , Cloretos/metabolismo , Hipertensão/metabolismo , Músculo Liso Vascular/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Captopril/farmacologia , Tamanho Celular , Artérias Cerebrais/patologia , Modelos Animais de Doenças , Genisteína/farmacologia , Hipertensão/tratamento farmacológico , Hipertensão/patologia , Músculo Liso Vascular/patologia , Técnicas de Patch-Clamp , Proteínas Tirosina Quinases/fisiologia , Ratos , Ratos Endogâmicos , Vanadatos/farmacologia
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