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1.
Lab Invest ; 104(7): 102087, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797344

RESUMO

Addressing the existing gaps in our understanding of sex- and strain-dependent disparities in renal microhemodynamics, this study conducted an investigation into the variations in renal function and related biological oscillators. Using the genetically diverse mouse models BALB/c, C57BL/6, and Kunming, which serve as established proxies for the study of renal pathophysiology, we implemented laser Doppler flowmetry conjoined with wavelet transform analyses to interrogate dynamic renal microcirculation. Creatinine, urea, uric acid, glucose, and cystatin C levels were quantified to investigate potential divergences attributable to sex and genetic lineage. Our findings reveal marked sexual dimorphism in metabolite concentrations, as well as strain-specific variances, particularly in creatinine and cystatin C levels. Through the combination of Mantel tests and Pearson correlation coefficients, we delineated the associations between renal functional metrics and microhemodynamics, uncovering interactions in female BALB/c mice for creatinine and uric acid, and in male C57BL/6 mice for cystatin C. Histopathologic examination confirmed an augmented microvascular density in female mice and elucidating variations in the expression of estrogen receptor ß among the strains. These data collectively highlight the influence of both sex and genetic constitution on renal microcirculation, providing an understanding that may inform the etiologic exploration of renal ailments.


Assuntos
Rim , Animais , Feminino , Masculino , Rim/metabolismo , Rim/irrigação sanguínea , Camundongos , Caracteres Sexuais , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microcirculação , Cistatina C/metabolismo , Cistatina C/sangue , Creatinina/sangue , Especificidade da Espécie , Fluxometria por Laser-Doppler , Ácido Úrico/sangue , Ácido Úrico/metabolismo , Fatores Sexuais
2.
Microcirculation ; : e12876, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39005221

RESUMO

OBJECTIVE: Abnormal tumor vascular network contributes to aberrant blood perfusion and reduced oxygenation in tumors, which lead to poor efficacy of chemotherapy and radiotherapy. We aimed to explore the effects of the tumor-derived exosomes (TDEs) and C188-9 (a small molecule inhibitor of signal transducer and activator of transcription 3, STAT3) on tumor microvascular hemodynamics and determine which blood flow oscillations for various frequency intervals are responsible for these changes. METHODS: Microvascular hemodynamics parameters were recorded using a PeriFlux 6000 EPOS system in tumor surface in a nude mouse subcutaneous xenograft model. Oscillations of laser Doppler flowmetry (LDF) signal were investigated by wavelet transform analysis. RESULTS: TDEs facilitated tumor growth at least partially was associated with increasing blood flow in smaller vessels with lower speed and decreasing the blood flow at larger vessels with higher speed. Lower oxyhemoglobin saturation (SO2) on tumor surface was aggravated by TDEs, and C188-9 treatment significantly alleviated this decrease. Wavelet transform spectral analysis revealed that TDEs increased the amplitude of oscillations in four frequency intervals related to endothelial (NO-dependent and -independent), myogenic and neurogenic activities, and C188-9 had no effect on this increase. CONCLUSIONS: TDEs facilitated tumor growth partially was associated with increasing blood flow in distributing vessels, reducing blood perfusion in larger vessels, and lowering SO2 on tumor surface. Enhanced vascular smooth muscle, endothelial and neurogenic activities occurred in tumor superficial zone.

3.
Microvasc Res ; 151: 104617, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37918522

RESUMO

Type 1 diabetes mellitus (T1DM) is predominantly managed using insulin replacement therapy, however, pancreatic microcirculatory disturbances play a critical role in T1DM pathogenesis, necessitating alternative therapies. This study aimed to investigate the protective effects of glycine supplementation on pancreatic microcirculation in T1DM. Streptozotocin-induced T1DM and glycine-supplemented mice (n = 6 per group) were used alongside control mice. Pancreatic microcirculatory profiles were determined using a laser Doppler blood perfusion monitoring system and wavelet transform spectral analysis. The T1DM group exhibited disorganized pancreatic microcirculatory oscillation. Glycine supplementation significantly restored regular biorhythmic contraction and relaxation, improving blood distribution patterns. Further-more, glycine reversed the lower amplitudes of endothelial oscillators in T1DM mice. Ultrastructural deterioration of islet microvascular endothelial cells (IMECs) and islet microvascular pericytes, including membrane and organelle damage, collagenous fiber proliferation, and reduced edema, was substantially reversed by glycine supplementation. Additionally, glycine supplementation inhibited the production of IL-6, TNF-α, IFN-γ, pro-MMP-9, and VEGF-A in T1DM, with no significant changes in energetic metabolism observed in glycine-supplemented IMECs. A statistically significant decrease in MDA levels accompanied by an increase in SOD levels was also observed with glycine supplementation. Notably, negative correlations emerged between inflammatory cytokines and microhemodynamic profiles. These findings suggest that glycine supplementation may offer a promising therapeutic approach for protecting against pancreatic microcirculatory dysfunction in T1DM.


Assuntos
Diabetes Mellitus Tipo 1 , Ilhotas Pancreáticas , Camundongos , Animais , Microcirculação , Células Endoteliais , Ilhotas Pancreáticas/irrigação sanguínea , Ilhotas Pancreáticas/metabolismo , Suplementos Nutricionais
4.
Int J Med Sci ; 21(2): 404-412, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169581

RESUMO

Atherosclerosis, a chronic inflammation of blood vessel walls, is a progressive pathophysiological process characterized by lipid deposition and innate adaptive immune responses. Arteriosclerosis often leads to narrowing of blood vessels. At present, interventional stent therapy is the main treatment method for vascular stenosis, which has the advantages of less trauma, less risk and faster recovery. However, atherosclerosis occurs in a complex pathophysiological environment. Stenting inevitably causes local tissue damage, leading to complications such as inflammation, intimal hyperplasia, late thrombosis, stent restenosis and other complications. It is urgent to optimize interventional therapy program. This article summarizes the advantages and disadvantages of absorbable metal scaffolds and the research progress of absorbable polymer scaffolds. The optimization strategy of stent is proposed. The status quo of drug coating was summarized. The prospect of new stent. To improve the therapeutic effect of arteriosclerosis.


Assuntos
Aterosclerose , Trombose , Humanos , Implantes Absorvíveis , Stents/efeitos adversos , Trombose/etiologia , Inflamação/complicações
5.
Ren Fail ; 46(1): 2329249, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38482598

RESUMO

BACKGROUND: Renal microcirculation plays a pivotal role in kidney function by maintaining structural and functional integrity, facilitating oxygen and nutrient delivery, and waste removal. However, a thorough bibliometric analysis in this area remains lacking. Therefore, we aim to provide valuable insights through a bibliometric analysis of renal microcirculation literature using the Web of Science database. METHODS: We collected renal microcirculation-related publications from the Web of Science database from January 01, 1990, to December 31, 2022. The co-authorship of authors, organizations, and countries/regions was analyzed with VOSviewer1.6.18. The co-occurrence of keywords and co-cited references were analyzed using CiteSpace6.1.R6 software to generate visualization maps. Additionally, burst detection was applied to keywords and cited references to forecast research hotspots and future trends. RESULTS: Our search yielded 7462 publications, with the American Journal of Physiology-Renal Physiology contributing the most articles. The United States, Mayo Clinic, and Lerman Lilach O emerged with the highest publication count, indicating their active collaborations. 'Type 2 diabetes' was the most significant keyword cluster, and 'diabetic kidney disease' was the largest cluster of cited references. 'Cardiovascular outcome' and 'diabetic kidney diseases' were identified as keywords in their burst period over the past three years. CONCLUSION: Our bibliometric analysis illuminates the contours of nephrology and microcirculation research, revealing a landscape ripe for challenges and the seeds of future scientific innovation. While the trends discerned from the literature emerging opportunities in diagnostic innovation, renal microcirculation research, and precision medicine interventions, their translation to clinical practice is anticipated to be a deliberate process.


Assuntos
Nefropatias Diabéticas , Rim , Humanos , Microcirculação , Bibliometria , Bases de Dados Factuais
6.
Microcirculation ; 29(6-7): e12724, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34351675

RESUMO

OBJECTIVE: The contractile behavior of collecting lymphatic vessels occurs in essential hypertension in response to homeostasis, suggesting a possible role for microcirculation. We aimed to clarify the nature of the lymphatic microcirculation profile in spontaneously hypertensive rats (SHRs) and normotensive controls. METHODS: The vasomotion of collecting lymphatic vessels in eight- and thirteen-week-old SHRs and age-matched Wistar-Kyoto rats (WKYs, n = 4 per group) was visualized by intravital video and VasTrack. The lymphatic vasomotion profile (frequency and amplitude) and contractile parameters (contraction fraction and total contractility activity index) were compared. Plasma nitrite/nitrate levels were assessed by the Griess reaction, and plasma endothelin-1 was measured by enzyme-linked immunosorbent assay. RESULTS: WKYs and SHRs differed in the vasomotion of collecting lymphatic vessels. Both eight- and thirteen-week-old WKYs revealed a high-amplitude pumping pattern, whereas a low-amplitude pattern was observed in SHRs. Moreover, compared with age-matched WKYs, SHRs exhibited deteriorated output and reflux capability and lost the ability to regulate collecting lymphatic vasomotion. Additionally, the chemistry complements the microcirculatory lymphatic profile as demonstrated by an increase in plasma nitrite, nitrate, and endothelin-1 in SHRs. ET-1 inhibitor meliorated the lymphatic contractile capability in SHRs partially through regulating frequency of lymphatic vasomotion. CONCLUSIONS: We used an intravital lymphatic imaging system to observe that SHRs exhibit an impaired collecting lymphatic vasomotion profile and deteriorated contractility and reflux.


Assuntos
Hipertensão , Vasos Linfáticos , Ratos , Animais , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Microcirculação , Endotelina-1 , Nitratos , Nitritos , Pressão Sanguínea
7.
J Pharmacol Exp Ther ; 382(1): 11-20, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35512800

RESUMO

Breast cancer remains the leading cause of cancer-related death among women worldwide. Sodium pentobarbital was found to play an inhibitory role in glioma growth in rats. In this study, we aimed to evaluate the effects of sodium pentobarbital on breast cancer growth both in vitro and in vivo, and its impacts on the microcirculatory changes on both skin and tumor surface in mice bearing subcutaneous xenograft. Cell counting assay was used to assess the antiproliferative effect of sodium pentobarbital on MDA-MB-231 breast cancer cells. Subcutaneous xenograft model was established to study the role of sodium pentobarbital on in vivo tumor growth. Speed-resolved blood perfusion, hemoglobin oxygen saturation (SO2, %), total hemoglobin tissue concentration (ctTHb, µM), and red blood cell (RBC) tissue fraction (%) were examined simultaneously by using enhanced perfusion and oxygen saturation system to investigate the effects of sodium pentobarbital on microcirculatory hemodynamics and oxygenation. Sodium pentobarbital suppressed breast tumor growth both in vitro and in vivo. Cutaneous blood flux in nutritive capillaries with low-speed flow was significantly increased in tumor-bearing mice, and high-dose sodium pentobarbital treatment cause a reduction in this low-speed blood flux, whereas sodium pentobarbital therapy caused an elevated blood flux in larger microvessels with mid and high speed in a dose-dependent manner. Different doses of sodium pentobarbital exerted different actions on SO2, ctTHb, and RBC tissue fraction. Collectively, the inhibitory effect of sodium pentobarbital on breast tumor growth was at least partly associated with its ability to normalize microcirculatory hemodynamics and oxygenation in tumors. SIGNIFICANCE STATEMENT: This study is the first to demonstrate the inhibiting effect of sodium pentobarbital on breast cancer growth both in vitro and in vivo, and such an inhibition was at least partly associated with its ability to normalize microcirculatory hemodynamics and oxygenation in tumors.


Assuntos
Neoplasias da Mama , Oxigênio/metabolismo , Pentobarbital , Animais , Neoplasias da Mama/tratamento farmacológico , Feminino , Hemodinâmica , Hemoglobinas/metabolismo , Humanos , Camundongos , Microcirculação , Pentobarbital/farmacologia , Ratos , Sódio
8.
Cancer Sci ; 112(3): 1289-1299, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33484209

RESUMO

Tumor angiogenesis is a crucial step in the further growth and metastasis of solid tumors. However, its regulatory mechanism remains unclear. Here, we showed that TARBP2, an RNA-binding protein, played a role in promoting tumor-induced angiogenesis both in vitro and in vivo through degrading the mRNAs of antiangiogenic factors, including thrombospondin1/2 (THBS1/2), tissue inhibitor of metalloproteinases 1 (TIMP1), and serpin family F member 1 (SERPINF1), by targeting their 3'untranslated regions (3'UTRs). Overexpression of TARBP2 promotes tumor cell-induced angiogenesis, while its knockdown inhibits tumor angiogenesis. Clinical cohort analysis revealed that high expression level of TARBP2 was associated with poor survival of lung cancer and breast cancer patients. Mechanistically, TARBP2 physically interacts with the stem-loop structure located in the 3'UTR of antiangiogenic transcripts, leading to mRNA destabilization by the dsRNA-binding domains 1/2 (dsRBDs1/2). Notably, the expression level of TARBP2 in human tumor tissue is negatively correlated with the expression of antiangiogenic factors, including THBS1/2, and brain-specific angiogenesis inhibitor 1 (BAI1). Moreover, TARBP2 expression is strongly associated with tumor angiogenesis in a group of human lung cancer samples. Collectively, our results highlight that TARBP2 is a novel tumor angiogenesis regulator that could promote tumor angiogenesis by selectively downregulating antiangiogenic gene expression.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias/patologia , Neovascularização Patológica/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Regiões 3' não Traduzidas/genética , Linhagem Celular Tumoral , Proteínas do Olho/genética , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias/irrigação sanguínea , Neoplasias/genética , Neovascularização Patológica/patologia , Fatores de Crescimento Neural/genética , Estabilidade de RNA/genética , Proteínas de Ligação a RNA/genética , RNA-Seq , Serpinas/genética , Trombospondina 1/genética , Trombospondinas/genética , Inibidor Tecidual de Metaloproteinase-1/genética
9.
Microcirculation ; 28(5): e12691, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33655585

RESUMO

OBJECTIVE: As an integrated system, pancreatic microcirculatory disturbance plays a vital role in the pathogenesis of type 1 diabetes mellitus (T1DM), which involves changes in microcirculatory oxygen and microhemodynamics. Therefore, we aimed to release type 1 diabetic and insulin-administrated microcirculatory profiles of the pancreas. METHODS: BALB/c mice were assigned to control, T1DM, and insulin-administrated groups randomly. T1DM was induced by intraperitoneal injection of streptozotocin (STZ). 1.5 IU insulin was administrated subcutaneously to keep the blood glucose within the normal range. After anesthetizing by isoflurane, the raw data set of pancreatic microcirculation was collected by the multimodal device- and computer algorithm-based microcirculatory evaluating system. After adjusting outliers and normalization, pancreatic microcirculatory oxygen and microhemodynamic data sets were imported into the three-dimensional module and compared. RESULTS: Microcirculatory profiles of the pancreas in T1DM exhibited a loss of microhemodynamic coherence (significantly decreased microvascular blood perfusion) accompanied by an impaired oxygen balance (significantly decreased PO2 , SO2 , and rHb). More importantly, with insulin administration, the pathological microcirculatory profiles were partially restored. Meanwhile, there were correlations between pancreatic microcirculatory blood perfusion and PO2 levels. CONCLUSIONS: Our findings establish the first integrated three-dimensional pancreatic microcirculatory profiles of STZ-induced and insulin-administrated T1DM.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Microcirculação , Animais , Diabetes Mellitus Tipo 1/induzido quimicamente , Insulina/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Oxigênio , Pâncreas , Estreptozocina
10.
Cell Biochem Funct ; 39(2): 308-316, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32876972

RESUMO

Cancer cell derived exosomes play important roles in cancer progression and modulation of the tumour microenvironment. This study aims to investigate the role of prokineticin receptor 1 (PKR1) positive exosomes on angiogenesis. In the present study, PKR1 expression in tumour samples from ovarian cancer patients were examined firstly. Then, two ovarian cancer cell lines, namely A2780 and HO-8910 cells, were used to isolate and obtain the PKR1 positive exosomes from the serum free medium. The function analysis of PKR1 positive exosomes on angiogenesis was conducted by cell proliferation and migration assay, tube formation analysis, and tumour volume assay. The results showed that PKR1 expression was down regulated in tumour samples of ovarian cancer patients compared with adjacent normal tissues. The intracellular expression of PKR1 could be detected in A2780 and HO-8910 cells. And, the isolated exosomes from the serum free medium were confirmed by transmission electron microscopic and NTA analysis, as well as the co-presence of PKR1 with exosome marker CD63. The function analysis of PKR1 positive exosomes on angiogenesis demonstrated the uptake of PKR1 positive exosomes by human umbilical vein endothelial cells through immunofluorescence staining. The angiogenesis assays in vitro indicated that PKR1 positive exosomes promoted migration and tube formation of HUVECs but not proliferation. The endogenous PKR1 was also verified to help to enhance migration and promote tube formation of vascular endothelial cells, which might involved in the phosphorylation of STAT3. Additionally, The tumour volume from exosomes treated A2780 tumour-bearing mice was significantly increased compared with the control group, accompanied with the induced PKR1 expression and phosphorylation of STAT3 level. SIGNIFICANCE OF THE STUDY: This study proved the important role of PKR1 positive exosomes released from ovarian cancer cells on promoting angiogenesis. The data indicated that PKR1 derived from ovarian cancer cells could act as an important tumour associated antigen and biomolecular factor for cellular communication in tumour microenvironment.


Assuntos
Exossomos/metabolismo , Hormônios Gastrointestinais/metabolismo , Neovascularização Fisiológica , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Exossomos/transplante , Feminino , Hormônios Gastrointestinais/antagonistas & inibidores , Hormônios Gastrointestinais/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Nus , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Fosforilação , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Transplante Heterólogo , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina/antagonistas & inibidores , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina/genética
11.
Biotechnol Lett ; 42(3): 389-401, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31919615

RESUMO

OBJECTIVE: This study is to explore the exact roles of extracellular vesicle (EVs) miRNAs from brain microvascular pericytes in the pathogenesis of hypertension. RESULTS: Forty-eight significantly differentially expressed miRNAs were identified, of which 17 were found to be upregulated and 31 were found to be downregulated in brain microvascular pericytes of spontaneous hypertensive rats, compared with that of normotension Wistar Kyoto rats. The GO enrichment analysis verified that the target genes were enriched in signaling pathways and molecular functions, such as metal ion binding, nucleotide binding and ATP binding. The KEGG analysis indicated that the target genes were enriched in Linoleic acid, alpha-linolenic acid and sphingolipid metabolism pathways. CONCLUSIONS: Several EV derived miRNAs, such as miR-21-5p, let-7c-5p and let-7a-5p, were found to be abnormally expressed in brain microvascular pericytes obtained from spontaneous hypertensive rats, compared with that of normotension Wistar Kyoto rats. The results of our research provide more insights into the functional link between brain microvascular pericytes and the pathogenesis of hypertension.


Assuntos
Encéfalo , MicroRNA Circulante/biossíntese , Vesículas Extracelulares/metabolismo , Regulação da Expressão Gênica , Hipertensão/metabolismo , Microvasos/metabolismo , Pericitos/metabolismo , Animais , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Encéfalo/patologia , Vesículas Extracelulares/patologia , Hipertensão/patologia , Microvasos/patologia , Pericitos/patologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
12.
Microcirculation ; 26(1): e12515, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30431204

RESUMO

OBJECTIVE: To investigate the effects of TNF-α-induced exosomes release on the biological behavior, metabolism, and bioenergetics of HUVECs. METHODS: Exosomes were isolated from conditioned media of HUVECs by ultracentrifugation after treatment with or without TNF-α. HUVECs were treated with or without TNF-α, or different concentrations of exosomes isolated from conditioned media with or without TNF-α induction (TExo and CExo , respectively). RESULTS: The results showed that TNF-α significantly inhibited migration, tube formation, and increased apoptosis rate of HUVECs compared with controls. Furthermore, TNF-α-induced exosomes (TExo ) rather than CExo , indicated similar effects to inhibit migration, tube formation and promote endothelial apoptosis. Although TNF-α treatment did not show a statistical difference, TExo significantly inhibited extracellular OCR compared with controls. TExo could significantly inhibited intracellular OCR in a hypoxia condition. TNF-α significantly increased L-ECA compared with control cells, and TExo showed similar stimulative effect on L-ECA. CONCLUSIONS: TNF-α-induced exosomes could significantly (a) change migration, tube formation, and apoptosis; (b) inhibit endothelial extracellular OCR and intracellular OCR (hypoxia); (c) increase glycolysis rate of the endothelial cells. These data provide new evidence for exploring endothelial behavior regulation using exosomes and their effects on endothelial metabolism and bioenergetics.


Assuntos
Exossomos/fisiologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Apoptose , Movimento Celular , Células Cultivadas , Metabolismo Energético , Exossomos/efeitos dos fármacos , Glicólise , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/fisiologia , Células Endoteliais da Veia Umbilical Humana/ultraestrutura , Humanos , Hipóxia , Ácido Láctico/metabolismo , Consumo de Oxigênio
13.
Clin Exp Hypertens ; 41(4): 342-352, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29939761

RESUMO

This work was aimed to study skin blood perfusion, vasomotion and vascular responses of the Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) in different stages of age using spectral. Laser-Doppler flowmetry (LDF) was used to examine the ears and limbs of WKY (12 and 48 weeks old) and SHR (12 and 48 weeks old). The skin blood flow oscillations (SBFOs) were studied by wavelet spectral analysis of LDF tracings. Then, we observed that old groups showed decreased perfusion and SBFO in the ears of both SHR and WKY. The SHR showed obviously lower postocclusive reactive hypera (PORH) ratio at the same age. A decreased peak-time occurred in the SHR of old age group. After PORH test, a statistically significant increase was observed within all subintervals in the absolute amplitude of 12-week WKY and only within IV and III subintervals in the absolute amplitude of 12-week SHR. But, the absolute amplitude of 48-week WKY and SHR showed no statistically significant increase within all subintervals. Results indicated that local regulating function of peripheral vascular was impaired in rat with hypertension and aging. Abbreviations LDF: Laser-Doppler flowmetry; SBF: Skin blood flow; SBFO: Skin blood flow oscillation; PORH: Postocclusive reactive hyperemia; SHR: Spontaneously hypertensive rats; WKY: Wistar-Kyoto rats; LDF: Laser-Doppler flowmetry; LDI: Laser Doppler Imaging; BP: Blood pressure.


Assuntos
Envelhecimento/fisiologia , Hipertensão/fisiopatologia , Microvasos/diagnóstico por imagem , Pele/irrigação sanguínea , Animais , Pressão Sanguínea , Fluxometria por Laser-Doppler , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Análise de Ondaletas
14.
Chaos ; 29(4): 043104, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31042941

RESUMO

Emergence of self-organized behaviors in diverse living systems often depends on population density. In these systems, cell-cell communications are usually mediated by the surrounding environment. Collective behaviors (e.g., synchrony and dynamical quorum sensing) of such systems with stirred environment have been extensively studied, but the spatiotemporal dynamics of the oscillators coupled via a diffusive environment (without stirring) is rather understudied. We here perform a computational study on the selection and competition of wave patterns in arrays of spatially distributed oscillators immersed in a diffusive medium. We find that population density plays a crucial role in the selection of wave patterns: (i) for a single spiral in the system, its rotation either inward or outward could be controlled by population density, and (ii) for spiral and target waves coexisting initially in the system, wave competition happens and population density decides which type of wave will finally survive. The latter phenomenon is further confirmed in a system whose individual element is excitable rather than self-sustained oscillatory. The mechanism underlying all these observations is attributed to the frequency competition. Our results in the excitable case may have implications on the experimental results.

15.
Cell Physiol Biochem ; 49(6): 2371-2381, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30261499

RESUMO

BACKGROUND/AIMS: Vascular calcification and hypertension are intimately linked, and the progression of hypertension is closely correlated with endothelial dysfunction. However, the role of endothelial cells (ECs) in vascular calcification of hypertension remains unclear. Therefore, the present study explored the effects of ECs on calcification of smooth muscle cells (SMCs) from aortas of spontaneously hypertensive rats (SHR). METHODS: Aortic ECs and SMCs were isolated from SHR and Wistar rats, respectively. The roles of ECs in the regulation of SMCs calcification were investigated by co-culture and conditioned culture model. Calcium deposition of SMCs was detected by von Kossa staining. Quantization of calcium content in SMCs was determined colorimetrically by the o-cresolphthalein complexone method. Alkaline phosphatase (ALP) activity was measured colorimetrically by p-nitrophenol. The expression levels of MMP-2, MMP-9 and the calcification-promoting proteins were analyzed by Western blot. RESULTS: Calcium deposition, ALP activity and the expression levels of calcification-promoting proteins in SMCs of SHR were significantly higher than that cultured without ECs after 6 days of co-culture with ECs or conditioned culture with the medium of ECs, however, there were no statistical differences between SMCs of Wistar rats. MMP-2 and MMP-9 in co-cultured ECs from SHR were dramatically higher than that cultured without SMCs, nevertheless, there were no statistical differences between ECs from Wistar rats and between SMCs from SHR or Wistar rats. Moreover, SB-3CT, a specific inhibitor of gelatinases, decreased calcium content and the expression levels of calcification-promoting proteins in both co-cultured and conditionally cultured SMCs from SHR. CONCLUSION: ECs have the ability to promote calcification of aortic SMCs of SHR, and elevated expressions of MMP-2 and MMP-9 in ECs of SHR might facilitate the calcification of SMCs.


Assuntos
Aorta/citologia , Cálcio/metabolismo , Células Endoteliais/metabolismo , Miócitos de Músculo Liso/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Cálcio/análise , Técnicas de Cocultura , Colorimetria , Células Endoteliais/citologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Miócitos de Músculo Liso/citologia , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Fatores de Transcrição/metabolismo
16.
Microcirculation ; 25(4): e12450, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29575333

RESUMO

OBJECTIVE: Islet microcirculation is mainly composed by IMECs. The aim of the study was to investigate the differences in gene expression profiles of IMECs upon glucose toxicity exposure and insulin treatment. METHODS: IMECs were treated with 5.6 mmol L-1 glucose, 35 mmol L-1 glucose, and 35 mmol L-1 glucose plus 10-8  mol L-1 insulin, respectively. Gene expression profiles were determined by microarray and verified by qPCR. GO terms and KEGG analysis were performed to assess the potential roles of differentially expressed genes. The interaction and expression tendency of differentially expressed genes were analyzed by Path-Net algorithm. RESULTS: Compared with glucose toxicity-exposed IMECs, 1574 mRNAs in control group and 2870 mRNAs in insulin-treated IMECs were identified with differential expression, respectively. GO and KEGG pathway analysis revealed that these genes conferred roles in regulation of apoptosis, proliferation, migration, adhesion, and metabolic process etc. Additionally, MAPK signaling pathway and apoptosis were the dominant nodes in Path-Net. IMECs survival and function pathways were significantly changed, and the expression tendency of genes from euglycemia and glucose toxicity exposure to insulin treatment was revealed and enriched in 7 patterns. CONCLUSIONS: Our study provides a microcirculatory framework for gene expression profiles of glucose toxicity-exposed IMECs.


Assuntos
Células Endoteliais/metabolismo , Glucose/toxicidade , Ilhotas Pancreáticas/irrigação sanguínea , Microcirculação , Transcriptoma , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/genética , Humanos , Insulina/farmacologia , Insulina/uso terapêutico
17.
Biochem Biophys Res Commun ; 470(2): 287-293, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26797522

RESUMO

Matrix metalloproteinase-2 (MMP-2), also known as gelatinase A, is involved in vascular calcification. Another member of gelatinases is MMP-9 (gelatinase B). However, the role of gelatinases in the pathogenesis of vascular calcification is not well understood. The current study aims to clarify the relationship between gelatinases and vascular calcification and to elucidate the underlying mechanism. Beta-glycerophosphate (ß-GP) was used to induce calcification of vascular smooth muscle cells (VSMCs) with or without 2-[[(4-Phenoxyphenyl)sulfonyl]methyl]-thiirane (SB-3CT), a specific gelatinases inhibitor. Levels of calcification were determined by assessing calcium content and calcification area of VSMCs. Phenotype transition of VSMCs was observed by assessing expressions of alkaline phosphatase (ALP), smooth muscle α-actin (SM-α-actin) and desmin. Gelatin zymography was applied to determine the activities of gelatinases, and western blot was applied to determine expressions of gelatinases, bone morphogenetic protein-2 (BMP-2), Runt-related transcription factor 2 (RUNX2) and msh homeobox homolog 2 (Msx-2). Gelatinases inhibition by SB-3CT alleviated calcification and phenotype transition of VSMCs induced by ß-GP. Increased gelatinases expression and active MMP-2 were observed in calcifying VSMCs. Gelatinases inhibition reduced expression of RUNX2, Msx-2 and BMP-2. BMP-2 treatment increased expressions of RUNX2 and Msx-2, while noggin, an antagonist of BMP-2, decreased expressions of RUNX2 and Msx-2. Gelatinases promote vascular calcification by upregulating BMP-2 which induces expression of RUNX2 and Msx-2, two proteins associated with phenotype transition of VSMCs in vascular calcification. Interventions targeting gelatinases inhibition might be a proper candidate for ameliorating vascular calcification.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Gelatinases/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia , Animais , Células Cultivadas , Masculino , Músculo Liso Vascular/patologia , Ratos , Ratos Wistar , Regulação para Cima
18.
J Chem Phys ; 140(18): 184901, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24832300

RESUMO

Chirality is one of the most fundamental properties of many physical, chemical, and biological systems. However, the mechanisms underlying the onset and control of chiral symmetry are largely understudied. We investigate possibility of chirality control in a chemical excitable system (the Belousov-Zhabotinsky reaction) by application of a chiral (rotating) electric field using the Oregonator model. We find that unlike previous findings, we can achieve the chirality control not only in the field rotation direction, but also opposite to it, depending on the field rotation frequency. To unravel the mechanism, we further develop a comprehensive theory of frequency synchronization based on the response function approach. We find that this problem can be described by the Adler equation and show phase-locking phenomena, known as the Arnold tongue. Our theoretical predictions are in good quantitative agreement with the numerical simulations and provide a solid basis for chirality control in excitable media.


Assuntos
Difusão , Campos Eletromagnéticos , Modelos Teóricos , Simulação por Computador
19.
Int J Surg Case Rep ; 120: 109905, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38875831

RESUMO

INTRODUCTION AND IMPORTANCE: Embolization of an arteriovenous malformation (AVM) via the anterior inferior cerebellar artery (AICA) is difficult. The "pressure cooker" technique in the AICA via a marathon microcatheter can be effective. CASE STUDY: A 43-year-old man with a cerebellar hematoma involving the brainstem. Angiography revealed an AVM supplied by the right AICA. Embolizing the AVM by casting an Onyx-18 liquid embolic system assisted by the "pressure cooker" technique was planned. An Apollo microcatheter was used for Onyx casting, and a Marathon microcatheter was used to establish a coiling plug to prevent Onyx reflux. The AVM was obliterated. Postoperatively, burr hole drainage of the cerebellar hematoma was performed. Postoperative computed tomography showed that the cerebellar hematoma and hydrocephalus had resolved. Magnetic resonance imaging revealed that there was no new serious infarction from damage to the cerebellum or brainstem. The patient recovered well. CLINICAL DISCUSSION: During Onyx casting, the drawback is that reflux can occlude normal vessels. The "pressure cooker" technique was useful for preventing Onyx reflux and for driving the Onyx to penetrate the AVM. However, it was difficult to use this technique in slim AICA; the Marathon microcatheter had a thinner tip than other microcatheters, and it can be used to establish the "pressure cooker" technique. This technique provides more solutions for AVMs in transarterial embolization through small feeding arteries. CONCLUSION: In a selective case, it was feasible to use the "pressure cooker" technique in the AICA via a Marathon microcatheter to embolize the AVM.

20.
Inflammation ; 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38240985

RESUMO

Endothelial dysfunction is associated with the development of hypertension. We hypothesize that inflammatory and normal endothelial exosomes play their roles by mediating endothelial function, and they induce endothelial angiogenesis through different signaling pathways. Endothelial cell-derived exosomes were isolated from the human umbilical vein endothelial cells (HUVECs) treated with (TExo) or without (CExo) tumor necrosis factor (TNF)-α. We monitored dermal microcirculation profiles in spontaneously hypertensive rats (SHRs) and WKY rats using a laser Doppler imager and a laser Doppler perfusion and temperature monitor. Tube formation, levels of angiogenesis-related proteins in HUVEC-conditioned media, and reactive oxygen species (ROS) levels were assessed following TNF-α, CExo, or TExo treatments. Western blot analysis was conducted to examine signaling proteins associated with inflammation and ROS. The results showed increased blood perfusion and the mean amplitude of endothelial oscillator in SHRs following CExo administration. TNF-α, CExo, and TExo treatments promoted endothelial tube formation and elevated levels of angiogenic factors and ROS. TExo significantly increased phosphorylation levels of STAT3, p38, and level of NF-κB, while decreasing phosphorylation levels of JNK and Erk (P < 0.01 or P < 0.05). CExo significantly increased STAT3 phosphorylation and reduced JNK and Erk phosphorylation (all P < 0.01). In conclusion, TNF-α and TExo induce inflammatory and pathological angiogenesis via the NF-κB pathway, while CExo exhibits a physiologically pro-angiogenic effect on endothelial cells. Increased ROS, interplaying with inflammatory signals, contribute to exosome-mediated alterations of endothelial function, thereby playing a role in the development of hypertension.

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