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1.
Chinese Journal of Biotechnology ; (12): 961-977, 2023.
Article in Chinese | WPRIM | ID: wpr-970416

ABSTRACT

Aromatic compounds are a class of organic compounds with benzene ring(s). Aromatic compounds are hardly decomposed due to its stable structure and can be accumulated in the food cycle, posing a great threat to the ecological environment and human health. Bacteria have a strong catabolic ability to degrade various refractory organic contaminants (e.g., polycyclic aromatic hydrocarbons, PAHs). The adsorption and transportation are prerequisites for the catabolism of aromatic compounds by bacteria. While remarkable progress has been made in understanding the metabolism of aromatic compounds in bacterial degraders, the systems responsible for the uptake and transport of aromatic compounds are poorly understood. Here we summarize the effect of cell-surface hydrophobicity, biofilm formation, and bacterial chemotaxis on the bacterial adsorption of aromatic compounds. Besides, the effects of outer membrane transport systems (such as FadL family, TonB-dependent receptors, and OmpW family), and inner membrane transport systems (such as major facilitator superfamily (MFS) transporter and ATP-binding cassette (ABC) transporter) involved in the membrane transport of these compounds are summarized. Moreover, the mechanism of transmembrane transport is also discussed. This review may serve as a reference for the prevention and remediation of aromatic pollutants.


Subject(s)
Humans , Adsorption , Bacteria/metabolism , Organic Chemicals , Biological Transport , ATP-Binding Cassette Transporters , Polycyclic Aromatic Hydrocarbons/metabolism
2.
Biol. Res ; 55: 35-35, 2022. ilus
Article in English | LILACS | ID: biblio-1429901

ABSTRACT

Extracellular vesicles (EVs) are naturally released membrane vesicles that act as carriers of proteins and RNAs for intercellular communication. With various biomolecules and specific ligands, EV has represented a novel form of information transfer, which possesses extremely outstanding efficiency and specificity compared to the classical signal transduction. In addition, EV has extended the concept of signal transduction to intercellular aspect by working as the collection of extracellular information. Therefore, the functions of EVs have been extensively characterized and EVs exhibit an exciting prospect for clinical applications. However, the biogenesis of EVs and, in particular, the regulation of this process by extracellular signals, which are essential to conduct further studies and support optimal utility, remain unclear. Here, we review the current understanding of the biogenesis of EVs, focus on the regulation of this process by extracellular signals and discuss their therapeutic value.


Subject(s)
Extracellular Vesicles/metabolism , Biological Transport , RNA/metabolism , Signal Transduction , Cell Communication/physiology
3.
Asian Journal of Andrology ; (6): 238-242, 2022.
Article in English | WPRIM | ID: wpr-928542

ABSTRACT

Cilium, an organelle with a unique proteome and organization, protruding from the cell surface, generally serves as a force generator and signaling compartment. During ciliogenesis, ciliary proteins are synthesized in cytoplasm and transported into cilia by intraflagellar transport (IFT) particles, where the inner counterparts undergo reverse trafficking. The homeostasis of IFT plays a key role in cilial structure assembly and signaling transduction. Much progress has been made on the mechanisms and functions of IFT; however, recent studies have revealed the involvement of IFT particle subunits in organogenesis and spermatogenesis. In this review, we discuss new concepts concerning the molecular functions of IFT protein IFT25 and how its interactions with other IFT particle subunits are involved in mammalian development and fertility.


Subject(s)
Animals , Male , Biological Transport , Carrier Proteins/metabolism , Cilia/metabolism , Flagella/metabolism , Mammals/metabolism , Organogenesis , Proteins/metabolism , Signal Transduction
4.
Rev. peru. med. exp. salud publica ; 38(1): 143-152, ene-mar 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1280560

ABSTRACT

RESUMEN La Organización Mundial de la Salud (OMS) ubica a la tuberculosis (TB) como uno de los problemas de salud más preocupantes en la actualidad, y señala que se requieren de acciones novedosas para controlar su expansión y, de esta manera, alcanzar una de las metas establecidas en los Objetivos de Desarrollo Sostenible: reducir para 2030 la morbilidad e incidencia de TB. Para lograr este objetivo, está claro que las herramientas empleadas actualmente para su diagnóstico y tratamiento ya no son las adecuadas. En este sentido, es necesario desarrollar nuevos medicamentos y vacunas, así como novedosos procedimientos de administración de fármacos que generen una mejor respuesta, disminuyan el tiempo y optimicen los tratamientos. La nanotecnología ha incorporado en los últimos años un gran número de nuevas herramientas que incrementan considerablemente, la diversidad de mecanismos para la administración de tratamientos antituberculosos. Dicho esto, la presente revisión describe brevemente el estado actual de la farmacorresistencia en TB, así como las características generales de las nanopartículas que están evaluándose como herramientas para transportar antibióticos antituberculosos.


ABSTRACT The World Health Organization (WHO) places Tuberculosis (TB) as one of the most important health problems today. According to the WHO, this disease requires novel actions to control its expansion and, in this way, achieve one of the goals established in the sustainable development goals: to reduce TB morbidity and incidence by 2030 and regain control. To achieve this goal, the tools currently used for diagnosis and treatment are no longer adequate. In this sense, it is necessary to develop new drugs and vaccines, as well as novel drug administration procedures that generate a better response, reduce times, and optimize treatments. Nanotechnology has incorporated in recent years a considerable number of new tools that significantly increase the diversity of mechanisms for the administration of anti-tuberculosis drugs. Therefore, the present review briefly describes the current state of drug resistance in tuberculosis, as well as the general characteristics of nanoparticles being evaluated as tools to transport new antibiotics against tuberculosis.


Subject(s)
Tuberculosis , Nanoparticles , Antibiotics, Antitubercular , Biological Transport , Drug Resistance, Microbial , Drug Carriers , Morbidity , Anti-Infective Agents
5.
Rev. peru. med. exp. salud publica ; 38(1): 143-152, ene-mar 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1280577

ABSTRACT

RESUMEN La Organización Mundial de la Salud (OMS) ubica a la tuberculosis (TB) como uno de los problemas de salud más preocupantes en la actualidad, y señala que se requieren de acciones novedosas para controlar su expansión y, de esta manera, alcanzar una de las metas establecidas en los Objetivos de Desarrollo Sostenible: reducir para 2030 la morbilidad e incidencia de TB. Para lograr este objetivo, está claro que las herramientas empleadas actualmente para su diagnóstico y tratamiento ya no son las adecuadas. En este sentido, es necesario desarrollar nuevos medicamentos y vacunas, así como novedosos procedimientos de administración de fármacos que generen una mejor respuesta, disminuyan el tiempo y optimicen los tratamientos. La nanotecnología ha incorporado en los últimos años un gran número de nuevas herramientas que incrementan considerablemente, la diversidad de mecanismos para la administración de tratamientos antituberculosos. Dicho esto, la presente revisión describe brevemente el estado actual de la farmacorresistencia en TB, así como las características generales de las nanopartículas que están evaluándose como herramientas para transportar antibióticos antituberculosos.


ABSTRACT The World Health Organization (WHO) places Tuberculosis (TB) as one of the most important health problems today. According to the WHO, this disease requires novel actions to control its expansion and, in this way, achieve one of the goals established in the sustainable development goals: to reduce TB morbidity and incidence by 2030 and regain control. To achieve this goal, the tools currently used for diagnosis and treatment are no longer adequate. In this sense, it is necessary to develop new drugs and vaccines, as well as novel drug administration procedures that generate a better response, reduce times, and optimize treatments. Nanotechnology has incorporated in recent years a considerable number of new tools that significantly increase the diversity of mechanisms for the administration of anti-tuberculosis drugs. Therefore, the present review briefly describes the current state of drug resistance in tuberculosis, as well as the general characteristics of nanoparticles being evaluated as tools to transport new antibiotics against tuberculosis.


Subject(s)
Tuberculosis , Drug Resistance, Microbial , Nanoparticles , Biological Transport , Pharmaceutical Preparations , Morbidity , Anti-Infective Agents , Antibiotics, Antitubercular
6.
Acta Physiologica Sinica ; (6): 681-689, 2021.
Article in Chinese | WPRIM | ID: wpr-887702

ABSTRACT

Prostaglandin E2 (PGE2), a bioactive lipid mediator, is one of the most important locally acting factors involved in a variety of physiological and pathophysiological processes. PGE2 binds with four EP receptors (EP1-4) to activate G protein-coupled receptor signaling responses. Recent functional and molecular studies have revealed that PGE2 plays an essential role in regulation of renal fluid transport via a variety of mechanisms. The water balance mainly depends on the regulation of aquaporin-2 (AQP2) by arginine vasopressin (AVP) in renal collecting duct principal cells. In recent years, increasing evidence suggests that PGE2 plays an important role in renal water reabsorption in the collecting ducts. In this paper, we reviewed the role of PGE2 and its receptors in the regulation of water reabsorption in the kidney, which may provide a new therapeutic strategy for many diseases especially nephrogenic diabetes insipidus.


Subject(s)
Humans , Aquaporin 2/metabolism , Biological Transport , Diabetes Insipidus, Nephrogenic , Dinoprostone , Water/metabolism
7.
Chinese Journal of Medical Genetics ; (6): 907-911, 2021.
Article in Chinese | WPRIM | ID: wpr-921967

ABSTRACT

ABCC1 gene is expressed in various tissues and organs of the human body, and can transport substrates including drugs, heavy metals, toxic substances and organic anions. Previous research on ABCC1 gene has mostly focused on tumor multidrug resistance. Recently, ABCC1 has been proposed as a candidate gene for hereditary hearing impairment, which has attracted much attention. ABCC1-associated deafness may be related to its role in biological barriers. This article has summarized recent progress in the study of the role of ABCC1 in the blood-testis barrier, placental barrier, blood-brain barrier, blood-labyrinth barrier, which may provide insight into its biological functions.


Subject(s)
Female , Humans , Male , Pregnancy , Biological Transport , Deafness/genetics , Multidrug Resistance-Associated Proteins/genetics , Placenta
8.
Chinese Journal of Biotechnology ; (12): 3020-3030, 2021.
Article in Chinese | WPRIM | ID: wpr-921403

ABSTRACT

P1B-ATPases are a group of proteins that can transport heavy metal ions across membranes by hydrolyzing ATP and they are a subclass of the P-type ATPase family. It was found that P1B-ATPases are mainly responsible for the active transport of heavy metal ions in plants and play an important role in the regulation of heavy metal homeostasis in plants. In this paper, we dissusses the mechanism of P1B-ATPases from the structure and classification of P1B-ATPases, and review the current research progress in the function of P1B-ATPases, in order to provide reference for future research and application of P1B-ATPases in improving crop quality and ecological environment management.


Subject(s)
Adenosine Triphosphatases/metabolism , Biological Transport , Metals, Heavy , Plants/enzymology
9.
China Journal of Chinese Materia Medica ; (24): 1795-1802, 2021.
Article in Chinese | WPRIM | ID: wpr-879094

ABSTRACT

This article aims to investigate the ameliorative effect of Linderae Radix ethanol extract on hyperlipidemia rats induced by high-fat diet and to explore its possible mechanism from the perspective of reverse cholesterol transport(RCT). SD rats were divided into normal group, model group, atorvastatin group, Linderae Radix ethanol extract(LREE) of high, medium, low dose groups. Except for the normal group, the other groups were fed with a high-fat diet to establish hyperlipidemia rat models; the normal group and the model group were given pure water, while each administration group was given corresponding drugs by gavage once a day for five weeks. Serum total cholesterol(TC), triglyceride(TG), high density lipoprotein-cholesterol(HDL-c), low density lipoprotein-cholesterol(LDL-c), alanine aminotransferase(ALT), and aspartate aminotransferase(AST) levels were measured by automatic blood biochemistry analyzer; the contents of TC, TG, total bile acid(TBA) in liver and TC and TBA in feces of rats were detected by enzyme colorimetry. HE staining was used to observe the liver tissue lesions; immunohistochemistry was used to detect the expression of ATP-binding cassette G8(ABCG8) in small intestine; Western blot and immunohistochemistry were used to detect the expression of peroxisome proliferator-activated receptor gamma/aerfa(PPARγ/α), liver X receptor-α(LXRα), ATP-binding cassette A1(ABCA1) pathway protein and scavenger receptor class B type Ⅰ(SR-BⅠ) in liver. The results showed that LREE could effectively reduce serum and liver TC, TG levels, serum LDL-c levels and AST activity, and increase HDL-c levels, but did not significant improve ALT activity and liver index; HE staining results showed that LREE could reduce liver lipid deposition and inflammatory cell infiltration. In addition, LREE also increased the contents of fecal TC and TBA, and up-regulated the protein expressions of ABCG8 in small intestine and PPARγ/α, SR-BⅠ, LXRα, and ABCA1 in liver. LREE served as a positive role on hyperlipidemia model rats induced by high-fat diet, which might be related to the regulation of RCT, the promotion of the conversion of cholesterol to the liver and bile acids, and the intestinal excretion of cholesterol and bile acids. RCT regulation might be a potential mechanism of LREE against hyperlipidemia.


Subject(s)
Animals , Rats , Biological Transport , Cholesterol/metabolism , Diet, High-Fat/adverse effects , Hyperlipidemias/metabolism , Liver/metabolism , Rats, Sprague-Dawley , Triglycerides/metabolism
10.
China Journal of Chinese Materia Medica ; (24): 52-56, 2021.
Article in Chinese | WPRIM | ID: wpr-878910

ABSTRACT

ATP-binding cassette(ABC) transporters are one of the largest protein families in organisms, with important effects in regulating plant growth and development, root morphology, transportation of secondary metabolites and resistance of stress. Environmental stress promotes the biosynthesis and accumulation of secondary metabolites, which determines the quality of medicinal plants. Therefore, how to improve the accumulation of secondary metabolites has been a hotspot in studying medicinal plants. Many studies have showed that ABC transporters are extremely related to the transportation and accumulation of secondary metabolites in plants. Recently, with the great development of genomics and transcriptomic sequencing technology, the regulatory mechanisms of ABC transporters on secondary metabolites have attached great attentions in medicinal plants. This paper reviewed the mechanisms of different groups of ABC transporters in transporting secondary metabolites through cell membranes. This paper provided key theoretical basis and technical supports in studying the mechanisms of ABC transporters in medicinal plant, and promoting the accumulation of secondary metabolites, in order to improve the quality of medicinal plants.


Subject(s)
ATP-Binding Cassette Transporters/metabolism , Biological Transport , Plant Development , Plants, Medicinal/metabolism , Stress, Physiological
11.
Braz. j. med. biol. res ; 52(8): e8596, 2019. tab, graf
Article in English | LILACS | ID: biblio-1011601

ABSTRACT

The peritoneal equilibration test (PET) is the most widespread method for assessing water and solute transport across the peritoneal membrane. This study compared three methods: traditional PET (t-PET), mini-PET, and modified PET (mod-PET). Non-diabetic adults (n=21) who had been on peritoneal dialysis (PD) for at least three months underwent t-PET (glucose 2.5%-4 h), mini-PET (glucose 3.86%-1 h), and mod-PET (glucose 3.86%-4 h) to determine dialysate-to-plasma concentration ratio (D/P) for creatinine and dialysate-to-baseline dialysate concentration ratio (D/D0) for glucose. Agreement between methods regarding D/P creatinine and D/D0 glucose was assessed using analysis of variance (ANOVA), Pearson's correlation coefficient, and Bland-Altman analysis. D/P creatinine differed between t-PET and mini-PET (P<0.001) and between mod-PET and mini-PET (P<0.01) but not between t-PET and mod-PET (P=0.746). The correlation of D/P creatinine with t-PET vs mod-PET was significant (r=0.387, P=0.009) but not that of t-PET vs mini-PET (r=0.088, P=0.241). Estimated bias was −0.029 (P=0.201) between t-PET and mod-PET, and 0.206 (P<0.001) between t-PET and mini-PET. D/D0 glucose differed between t-PET and mod-PET (P=0.003) and between mod-PET and mini-PET (P=0.002) but not between t-PET and mini-PET (P=0.885). The correlations of D/D0 glucose in t-PET vs mod-PET (r=−0.017, P=0.421) or t-PET vs mini-PET (r=0.152, P=0.609) were not significant. Estimated bias was 0.122 (P=0.026) between t-PET and mod-PET, and 0.122 (P=0.026) between t-PET and mini-PET. The significant correlation of D/P creatinine between t-PET and mod-PET suggested that the latter is a good alternative to t-PET. There was no such correlation between t-PET and mini-PET.


Subject(s)
Humans , Male , Female , Middle Aged , Peritoneal Dialysis/methods , Kidney Failure, Chronic/therapy , Peritoneum/metabolism , Biological Transport , Creatinine/blood , Glucose/analysis , Kidney Failure, Chronic/blood
12.
Adv Rheumatol ; 59: 20, 2019. tab
Article in English | LILACS | ID: biblio-1088591

ABSTRACT

Abstract Background: To date there are no specific classification criteria for childhood-onset systemic lupus erythematosus (cSLE). This study aims to compare the performance among the American College of Rheumatology (ACR) 1997, the Systemic Lupus International Collaborating Clinics criteria (SLICC) and the new European League Against Rheumatism (EULAR)/ACR criteria, in a cSLE cohort. Methods: We conducted a medical chart review study of cSLE cases and controls with defined rheumatic diseases, both ANA positive, to establish each ACR1997, SLICC and EULAR/ACR criterion fulfilled, at first visit and 1-year-follow-up. Results: Study population included 122 cSLE cases and 89 controls. At first visit, SLICC criteria had higher sensitivity than ACR 1997 (89.3% versus 70.5%, p < 0.001), but similar specificity (80.9% versus 83.2%, p = 0.791), however performance was not statistically different at 1-year-follow-up. SLICC better scored in specificity compared to EULAR/ACR score ≥ 10 at first visit (80.9% versus 67.4%, p = 0.008) and at 1-year (76.4% versus 58.4%, p = 0.001), although sensitivities were similar. EULAR/ACR criteria score ≥ 10 exhibited higher sensitivity than ACR 1997 (87.7% versus 70.5%, p < 0.001) at first visit, but comparable at 1-year, whereas specificity was lower at first visit (67.4% versus 83.2%, p = 0.004) and 1-year (58.4% versus 76.4%, p = 0.002). A EULAR/ACR score ≥ 13 against a score ≥ 10, resulted in higher specificity, positive predictive value, and cut-off point accuracy. Compared to SLICC, a EULAR/ACR score ≥ 13 resulted in lower sensitivity at first visit (76.2% versus 89.3%, p < 0.001) and 1-year (91% versus 97.5%, p = 0.008), but similar specificities at both assessments. When compared to ACR 1997, a EULAR/ACR total score ≥ 13, resulted in no differences in sensitivity and specificity at both observation periods. Conclusions: In this cSLE population, SLICC criteria better scored at first visit and 1-year-follow-up. The adoption of a EULAR/ACR total score ≥ 13 in this study, against the initially proposed ≥10 score, was most appropriate to classify cSLE. Further studies are necessary to address if SLICC criteria might allow fulfillment of cSLE classification earlier in disease course and may be more inclusive of cSLE subjects for clinical studies.


Subject(s)
Animals , Humans , Brain/metabolism , Pharmaceutical Preparations/metabolism , Blood-Brain Barrier/metabolism , Tissue Distribution/physiology , Models, Theoretical , Arachnoid/drug effects , Arachnoid/metabolism , Biological Transport/drug effects , Biological Transport/physiology , Brain/drug effects , Pharmaceutical Preparations/administration & dosage , Blood-Brain Barrier/drug effects , Tissue Distribution/drug effects , Extracellular Fluid/drug effects , Extracellular Fluid/metabolism
13.
Chinese Journal of Biotechnology ; (12): 1162-1173, 2019.
Article in Chinese | WPRIM | ID: wpr-771812

ABSTRACT

Cell-penetrating peptides (CPPs) are short peptides that can penetrate the cell membrane or tissue barrier. CPPs can deliver a variety of biomacromolecules, such as proteins, RNA and DNA, into cells to produce intracellular functional effects. Endocytosis and direct penetration have been suggested as the two major uptake mechanisms for CPPs-mediated cargo delivery. Compared with other non-natural chemical molecules-based delivery reagents, the CPPs have better biocompatibility, lower cytotoxicity, are easily degraded after cargo delivery, and can be fused and recombined expressed with bioactive proteins. Because of these advantages, the CPPs have become an important potential tool for delivery of developing drugs which targets intracellular factors. As a novel delivery tool, the CPPs also show promising application prospects in biomedical researches. This review summarized recent advances regarding the classification characteristics, the cellular uptake mechanisms and therapeutic application potentials of CPPs.


Subject(s)
Biological Transport , Cell Membrane , Cell-Penetrating Peptides , Metabolism , Endocytosis
14.
China Journal of Chinese Materia Medica ; (24): 167-174, 2019.
Article in Chinese | WPRIM | ID: wpr-771502

ABSTRACT

To investigate the active fraction from Bletilla striata in Caco-2 cell monolayer,so as to explore its absorption mechanism of oral administration preliminarily.Active fraction from B.striata in Caco-2 cell monolayer was analyzed by UPLC-Q-TOF and detected by UPLC-MS/MS,and the effects of different concentrations,pH and P-glycoprotein inhibitors on Caco-2 cells Monolayer were investigated.Six compounds were isolated from the active fraction of B.striata in Caco-2 cell monolayer by UPLC-Q-TOF,and identified as B6,B12,B14,B17,B19 and B23,with concentration dependence.Within the 0-180 min,the uptake of B12 and B14 had a time dependence,while B6,B17,B19 and B23 tended to saturate after 60 min.All of the components had a good absorption in an acidic environment.B6 had a good absorption at pH 6.0,while the other components B12,B14,B17,B19 and B23 had a good absorption at pH4.0.The absorption of the 6 main components of B.striata were not be affected by P-glycoprotein inhibitors(verapamil/cyclosporin A).Compared with the control group,there was no difference in the absorption of B6 and B12,and the absorption of B14,B17,B19 and B23 increased,but with no significant difference.The absorption characteristic of B.striata extract across the Caco-2 cell monolayer is probably passive diffusion,and the absorption process was not affected by P-glycoprotein.


Subject(s)
Humans , Biological Transport , Caco-2 Cells , Chromatography, Liquid , Intestinal Absorption , Orchidaceae , Chemistry , Plant Extracts , Pharmacology , Tandem Mass Spectrometry
15.
Acta Physiologica Sinica ; (6): 350-360, 2019.
Article in Chinese | WPRIM | ID: wpr-777179

ABSTRACT

Facilitative glucose transporters (GLUT) are proteins that mediate glucose transmembrane transport in the form of facilitated diffusion, which play an important role in regulating cell energy metabolism. There are many breakthroughs in researches of facilitative GLUT in recent years. It has been known that there are 14 subtypes of facilitative GLUT with obvious tissue specificity in distribution and physiological function. In the present review, the tissue and cellular distribution, subcellular localization, expression regulation, physiological function and the relationship to diseases of facilitative GLUT subtypes were summarized, in order to further understand their physiological and pathophysiological significances.


Subject(s)
Humans , Biological Transport , Disease , Energy Metabolism , Glucose , Glucose Transport Proteins, Facilitative , Physiology
16.
Journal of Zhejiang University. Science. B ; (12): 513-527, 2019.
Article in English | WPRIM | ID: wpr-776711

ABSTRACT

Aluminum (Al) is the most abundant metal element in the earth's crust. On acid soils, at pH 5.5 or lower, part of insoluble Al-containing minerals become solubilized into soil solution, with resultant highly toxic effects on plant growth and development. Nevertheless, some plants have developed Al-tolerance mechanisms that enable them to counteract this Al toxicity. One such well-documented mechanism is the Al-induced secretion of organic acid anions, including citrate, malate, and oxalate, from plant roots. Once secreted, these anions chelate external Al ions, thus protecting the secreting plant from Al toxicity. Genes encoding the citrate and malate transporters responsible for secretion have been identified and characterized, and accumulating evidence indicates that regulation of the expression of these transporter genes is critical for plant Al tolerance. In this review, we outline the recent history of research into plant Al-tolerance mechanisms, with special emphasis on the physiology of Al-induced secretion of organic acid anions from plant roots. In particular, we summarize the identification of genes encoding organic acid transporters and review current understanding of genes regulating organic acid secretion. We also discuss the possible signaling pathways regulating the expression of organic acid transporter genes.


Subject(s)
Aluminum , Toxicity , Anions , Biological Transport , Citric Acid , Metabolism , Malates , Metabolism , Oxalic Acid , Metabolism , Plant Roots , Metabolism , Signal Transduction , Physiology
17.
Biol. Res ; 51: 4, 2018. tab, graf
Article in English | LILACS | ID: biblio-888434

ABSTRACT

Abstract Aquaporins (AQP) are channel proteins belonging to the Major Intrinsic Protein (MIP) superfamily that play an important role in plant water relations. The main role of aquaporins in plants is transport of water and other small neutral molecules across cellular biological membranes. AQPs have remarkable features to provide an efficient and often, specific water flow and enable them to transport water into and out of the cells along the water potential gradient. Plant AQPs are classified into five main subfamilies including the plasma membrane intrinsic proteins (PIPs), tonoplast intrinsic proteins (TIPs), nodulin 26 like intrinsic proteins (NIPs), small basic intrinsic proteins (SIPs) and X intrinsic proteins (XIPs). AQPs are localized in the cell membranes and are found in all living cells. However, most of the AQPs that have been described in plants are localized to the tonoplast and plasma membranes. Regulation of AQP activity and gene expression, are also considered as a part of the adaptation mechanisms to stress conditions and rely on complex processes and signaling pathways as well as complex transcriptional, translational and posttranscriptional factors. Gating of AQPs through different mechanisms, such as phosphorylation, tetramerization, pH, cations, reactive oxygen species, phytohormones and other chemical agents, may play a key role in plant responses to environmental stresses by maintaining the uptake and movement of water in the plant body.


Subject(s)
Plants/metabolism , Stress, Physiological/physiology , Biological Transport/physiology , Aquaporins/metabolism , Gene Expression , Aquaporins/physiology
18.
São Paulo; s.n; 2018. 108 p.
Thesis in Portuguese | LILACS | ID: biblio-916041

ABSTRACT

Introdução: O diabetes mellitus (DM) está associado a complicações que comprometem a qualidade de vida e a sobrevida dos indivíduos. Além disso, acarreta elevados custos para o controle metabólico e o tratamento de suas complicações, sendo assim caracterizado como um problema de saúde pública. A regulação da digestão e da absorção intestinal dos carboidratos, com vista a manter a homeostase da glicose plasmática, constituem importantes estratégias de proteção em condições clínicas como o diabetes tipo 2 (DM2), obesidade e síndrome metabólica. Os compostos fenólicos compreendem um grupo complexo de fitoquímicos bioativos presentes nos vegetais. Estudos in vitro e in vivo têm demonstrado que os compostos fenólicos inibem a atividade de carbohidrases (α-amilase e α-glicosidase) e o transporte intestinal de glicose mediado pelos transportadores SGLT1 e GLUT2. O cerrado brasileiro compreende uma larga biodiversidade, porém, apesar de muitas espécies terem sido identificadas, o seu potencial nutritivo e funcional ainda é pouco conhecido. Dentre estas espécies nativas é destacado o jatobá-do-cerrado. O jatobá-do-cerrado é uma leguminosa nativa brasileira, cuja a polpa farinácea que envolve suas sementes apresenta quantidades significativas de compostos fenólicos, podendo ter um potencial efeito sobre o metabolismo da glicose. Objetivos: Verificar os efeitos dos compostos fenólicos da farinha de jatobá-do-cerrado na digestão de carboidratos e na captação de glicose em células intestinais Caco-2. Metodologia: Os compostos fenólicos da farinha de jatobá foram obtidos por extração sequencial com as soluções de etanol (60%) e acetona (70%). Em seguida, o extrato foi digerido utilizando enzimas (α-amilase, pepsina e pancreatina) em pH fisiológico. Os compostos fenólicos presentes no extrato antes e após a digestão foram identificados por cromatografia líquida de ultra performance - espectrômetro de massas (UPLC-MS/MS). Foi avaliada a capacidade de inibição dos extratos de jatobá digeridos em relação à atividade das enzimas α-amilase e α-glicosidase. Células intestinais Caco-2 foram incubadas com diferentes concentrações (0,05 mg/mL - 0,1 mg/mL) de extratos de farinha de jatobá digeridos em diferentes tempos (30 min, 2h e 12 h) para a avaliação da captação de glicose e da expressão gênica dos transportadores de glicose SGLT1 e GLUT2. Resultados: 44 compostos fenólicos foram identificados, dentre eles, a principal classe presente são os flavonoides. Compostos como o ácido cafeico, o kaempferol, quercetina-3- rutinosideo e a quercetrina estavam presentes no extrato antes da digestão. O conteúdo de compostos fenólicos do extrato foi reduzido após a digestão, entretanto o mesmo ainda apresentou compostos de relevância biológica como o ácido p-cumárico, ácido 3-o-feruloilquinico, theaflavina, crisina e grandinina que já apresentaram efeito positivo sobre o metabolismo da glicose in vitro em outros trabalhos. Os extratos fenólicos de jatobá após a digestão in vitro inibiram significativamente a atividade das enzimas α-amilase (76 e 91%) e α- glicosidase (53 e 77%). Os extratos também demonstraram inibir significativamente tanto a captação de glicose independente de sódio quanto a expressão gênica dos transportadores de glicose SGLT1 e GLUT2 de maneira dose-dependente. Conclusão: Este é o primeiro trabalho que identificou os compostos fenólicos presentes na farinha de jatobá. A partir do exposto, podemos concluir que a farinha de jatobá apresenta potencial benefício a saúde devido ao seu conteúdo de compostos fenólicos e a capacidade destes compostos de regular a digestão e a absorção de carboidratos in vitro


Introduction: Diabetes mellitus (DM) is associated with complications that decrease the quality of life and survival of individuals. In addition, it entails high costs for metabolic control and treatment of its complications, thus being characterized as a public health problem. The regulation of digestion and intestinal absorption of carbohydrates to maintain plasma glucose homeostasis are important strategies for protection in chronic diseases such as type 2 diabetes (DM2), obesity and metabolic syndrome. Phenolic compounds are a complex group of chemical substances present in plants. In vitro and in vivo studies have shown that phenolic compounds are able to inhibit the activity of carbohydrases (α-amylase and α-glycosidase) and the intestinal transport of glucose mediated by SGLT1 and GLUT2 transporters. Brazilian Cerrado present a large biodiversity, but although many species have been identified, its nutritional and functional potential is still little known. Among these native species is the jatobá-docerrado. Jatobá-do-cerrado is a brazilian native legume, whose farinaceous pulp that surrounds its seeds presents significant amounts of phenolic compounds and may have a potential effect on glucose metabolism. Objectives: To verify the effects of phenolic compounds from jatobá-do-cerrado flour in the digestion of carbohydrates and uptake of glucose in Caco-2 intestinal cells. Methods: Phenolic compounds of jatobá flour were obtained by sequential extraction with olutions of ethanol (60%) and acetone (70%). The extract was digested using enzymes (α-amylase, pepsin and pancreatin) at physiological pH. The phenolic compounds present in the extract before and after the digestion were identified by liquid chromatography of ultra-performance - mass spectrometer (UPLCMS / MS). The ability of inhibition of the extracts of jatobá digested in relation to the activity of α-amylase and α-glycosidase enzymes was evaluated. Caco-2 intestinal cells were incubated with different concentrations of jatobá flour extracts (0.1 mg / mL - 0.05 mg / mL) for different time (30 min, 2 h and 12 h) to the evaluation of facilitated uptake (sodium-free buffer) and gene expression of SGLT1 and GLUT2 glucose transporters. Results: 44 phenolic compounds have been identified, among them a major class present are flavonoids. Compounds such as caffeic acid, quercetin-3-rutinoside and quercetrine were present in the extract before in vitro digestion. The content of phenolic compounds of the extract after digestion was reduced. However, the extract presents compounds with biological activity such as p-coumaric acid, 3-o-feruloylquinic acid , theaflavin, chrysin and grandinine, which already presented positive effects on glucose metabolism in vitro in other studies. Phenolic extracts of jatobá after in vitro digestion inhibited the activity of α-amylase (76 and 91%) and α-glycosidase (53 and 77%). The extracts also shown to inhibit both glucose uptake and gene expression of glucose transporters SGLT1 and GLUT2 in a dose-dependent manner. Conclusion: This is the first work that identified the phenolic compounds present in jatobá flour. Thus, we can conclude that the jatobá flour presents potential health benefit by modulate digestion and the absorption of carbohydrates in vitro


Subject(s)
Absorption, Physiological/genetics , Caco-2 Cells , Diabetes Mellitus , Fabaceae , Glucose/pharmacology , Phenolic Compounds , Biological Availability , Biological Transport , Digestion , Flour
19.
China Journal of Chinese Materia Medica ; (24): 4132-4137, 2018.
Article in Chinese | WPRIM | ID: wpr-775367

ABSTRACT

Shuxiong prescription (Notoginseng Radix et Rhizoma, Chuanxiong Rhizome and Carthami Flos) has the function of activating blood circulation to dissipate blood stasis, activating meridians to stop pain. This paper was mainly aimed to discuss the transport characteristics of Shuxiong prescription across Caco-2 cell monolayer. Safe concentration range of Shuxiong prescription against Caco-2 cell monolayer model was determined by MTT assay. The mechanism of Shuxiong prescription bidirectional transport was investigated by Caco-2 cell monolayer model. The apparent permeability coefficient Papp of digoxin was determined by high performance liquid chromatography (HPLC). The test results showed that the Papp of extract from Notoginseng Radix et Rhizoma, Chuanxiong Rhizome, Carthami Flos, Chuanxiong Rhizome+Carthami Flos and Shuxiong prescription transport from apical (AP) side to basolateral (BL) side was (3.12±0.73)×10⁻⁶, (2.58±0.41)×10⁻⁶, (4.97±0.64)×10⁻⁶, (4.63±0.57)×10⁻⁶, (5.79±0.68)×10⁻⁶ cm·s⁻¹, respectively, indicating that the transport of digoxin across Caco-2 cell monolayer model was active absorption, and the P-gp protein took part in the process. Chuanxiong Rhizome could significantly decrease the transport of digoxin from BL→AP(<0.01) and increase its transport from AP→BL(<0.05) significantiy. After the addition of Shuxiong prescription, the transport of digoxin from BL→AP was significantly inhibited(<0.01). The results suggested that the extract of safflower had no effect on P-gp transport, nor on the independence diffusion of digoxin. The transport of digoxin could be degraded by the extract of Chuanxiong Rhizome and the extract of Shuxiong prescription from BL→AP(<0.01), significantly; pseudo-ginseng had no effect on the independence diffusion of digoxin; the extract of safflower+Chuanxiong Rhizome had the same experimental result as Chuanxiong Rhizome extract.


Subject(s)
Humans , Biological Transport , Caco-2 Cells , Chromatography, High Pressure Liquid , Digoxin , Pharmacokinetics , Drugs, Chinese Herbal , Pharmacokinetics
20.
Chinese Medical Journal ; (24): 2338-2345, 2018.
Article in English | WPRIM | ID: wpr-690217

ABSTRACT

<p><b>Objective</b>Endothelial cells (ECs) are important metabolic and endocrinal organs which play a significant role in regulating vascular function. Vascular ECs, located between the blood and vascular tissues, can not only complete the metabolism of blood and interstitial fluid but also synthesize and secrete a variety of biologically active substances to maintain vascular tension and keep a normal flow of blood and long-term patency. Therefore, this article presents a systematic review of common injuries and healing mechanisms for the vascular endothelium.</p><p><b>Data Sources</b>An extensive search in the PubMed database was undertaken, focusing on research published after 2003 with keywords including endothelium, vascular, wounds and injuries, and wound healing.</p><p><b>Study Selection</b>Several types of articles, including original studies and literature reviews, were identified and reviewed to summarize common injury and repair processes of the endothelial lining.</p><p><b>Results</b>Endothelial injury is closely related to the development of multiple cardiovascular and cerebrovascular diseases. However, the mechanism of vascular endothelial injury is not fully understood. Numerous studies have shown that the mechanisms of EC injury mainly involve inflammatory reactions, physical stimulation, chemical poisons, concurrency of related diseases, and molecular changes. Endothelial progenitor cells play an important role during the process of endothelial repair after such injuries. What's more, a variety of restorative cells, changes in cytokines and molecules, chemical drugs, certain RNAs, regulation of blood pressure, and physical fitness training protect the endothelial lining by reducing the inducing factors, inhibiting inflammation and oxidative stress reactions, and delaying endothelial caducity.</p><p><b>Conclusions</b>ECs are always in the process of being damaged. Several therapeutic targets and drugs were seeked to protect the endothelium and promote repair.</p>


Subject(s)
Humans , Biological Transport , Endothelial Cells , Endothelium, Vascular , Wounds and Injuries , Inflammation , Therapeutics
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