Morphological Effects of Cigarette Smoking on Respiratory System and Related Functions Based on AQPs Expression

SUMMARY: A great deal of attention of air pollution on respiratory health is increasing, particularly in relation to haze days. It is that exposure to cigarette smoke augments the toxicity of common air contaminants, thereby increasing the complexity of respiratory diseases. Although there are various mechanisms involved to respiratory diseases caused or worsen by cigarette smoking, in which the role of AQPs in the lung with regard to fluid homeostasis still remains elusive. In this paper, we copied the rat models based on smoke generator, and investigated the morphological changes of mucosa and related functions depending on the balance of lining liquid of alveoli via AQPs expression. Compared with normal group, weak labelling of AQP1 and AQP5 protein abundance were clearly detected in the corresponding part of smoke exposure groups compared with normal group. Hence, it is suggested that the contribution of AQPs in the lung is diminished, thereby causing perturbed balancing between resorptive and secretory fluid homeostasis under cigarette smoking.

Cada vez se presta más atención a la contaminación del aire en la salud respiratoria, particularmente, en relación con los días de neblina. En consecuencia la exposición al humo del cigarrillo aumenta la toxicidad de los contaminantes comunes del aire, lo que además aumenta la complejidad de las enfermedades respiratorias. Aunque existen varios mecanismos involucrados en las enfermedades respiratorias causadas o empeoradas por el tabaquismo, en las que el papel de las AQP en el pulmón respecto a la homeostasis de líquidos sigue siendo difícil de alcanzar. En este artículo, copiamos los modelos de rata basados en el generador de humo e investigamos los cambios morfológicos de la mucosa y las funciones relacionadas según el equilibrio del líquido de revestimiento de los alvéolos a través de la expresión de AQP. En comparación con el grupo normal, se detectó claramente un etiquetado débil de la abundancia de proteínas AQP1 y AQP5 en la parte correspondiente de los grupos de exposición al humo en comparación con el grupo control. Por lo tanto, se sugiere que la contribución de las AQP en el pulmón está disminuida, provocando así un equilibrio perturbado entre la homeostasis del líquido secretor y de reabsorción bajo el hábito de fumar cigarrillos.

Expression of V2R and AQPs in the renal medulla of high-fat nutritional obesity of rat / Expresión de V2R y AQPs en la médula renal de ratas con obesidad nutricional alta en grasas

Recent evidence has indicated that adipose tissue produces bioactive substances that contribute to obesity-related kidney disease, altering the renal function and structure. Eight of the AQPs are expressed in the kidney, where several of them contribute to water absorption and maintenance of body water balance. In the study, we mainly examined the localization of AQP2, AQP3 and V2R in renal medulla of Normal Diet (ND) and High-fat Diet (HFD) of rats, respectively. In renal medulla of HFD, immunolight microscopy revealed weak expression of AQP2 at the apical plasma membrane and intracellular vesicles of principal cells of the IMCD and OMCD. AQP3 and V2R expression also observed a decrease in immunolabelling in the IMCD and OMCD. It was suggested that excess lipid accumulation may lead to lipotoxicity and may be the major driver of organ dysfunction such as water reabsorption dysfunction, which may be resulted from abnormal response of rphan G-protein-coupled receptors in kidney.

La evidencia reciente ha indicado que el tejido adiposo produce sustancias bioactivas que contribuyen a la enfermedad renal relacionada con la obesidad, alterando la función y la estructura renal. Ocho de los AQP se expresan en el riñón, donde varios de ellos contribuyen a la absorción de agua y al mantenimiento del equilibrio hídrico corporal. En el estudio, examinamos principalmente la localización de AQP2, AQP3 y V2R en la médula renal de ratas con dieta normal (ND) y ratas con dieta alta en grasas (HFD). En la médula renal del grupo HFD, la microscopía electrónica de barrido reveló una expresión débil de AQP2 en la membrana plasmática apical y las vesículas intracelulares de las células principales de IMCD y OMCD. La expresión de AQP3 y V2R también observó una disminución en el inmunomarcador en IMCD y OMCD. Se sugiere que el exceso de acumulación de lípidos puede conducir a lipotoxicidad y ser el principal impulsor de la disfunción orgánica, como la disfunción de reabsorción de agua, que puede ser el resultado de la respuesta anormal de los receptores acoplados a proteína rphan G en el riñón.

Immunohistochemical study of aquaporin 1 and 2 in the hepatobiliary system of Qinghai lizard (Pphrynocephalus vlangalii ) / Estudio inmunohistoquímico de aquaporin 1 y 2 en la sistema hepatobiliar del lagarto de Qinghai ( Phrynocephalus vlangalii )

A serous membrane covering the liver and the hepatic parenchyma, consists of hepatocytes, arteries, veins, hepatic sinusoids and biliary ductuli. There are erythrocytes, thrombocytes, melanin particles and Kupffer cell in the hepatic sinusoids and the blood vessels. The gall bladder wall consists of a mucous layer a muscle layer and a serous layer. The bottom of the epithelium abounds with round or oval secretory. In liver, immunohistochemistry results show that AQP1 have intense reaction in hepatic lobule, Kupffer cells (Macrophagocytus stellatus), hepatocytes, portal tract, blood islands, vein and artery, but almost no reaction of AQP2 was detected. In gallbladder, mucous epithelium, endothelial cells from vein and artery all have strong AQP1 expression, AQP2 showed minor diffused positive reaction in gallbladder, which suggesting that AQP1 may have the main role in the absorption and transportation of fluid in hepatobiliary system of Qinghai Lizard.

Una membrana serosa cubre el hígado y el parénquima hepático el cual está formado por hepatocitos, arterias, venas, sinusoides hepáticos y conductos biliares. Se encuentran eritrocitos, trombocitos, partículas de melanina y células de Kupffer en los sinusoides hepáticos y en los vasos sanguíneos. La pared de la vesícula biliar presenta tres capas: mucosa, muscular y serosa. En el hígado, la inmunohistoquímica mostró que AQP1 tiene una reacción intensa en el lóbulo hepático, células de Kupffer, hepatocitos, tracto portal e islotes sanguíneos. En venas y arterias, no se detectó reacción alguna de AQP2. En la vesícula biliar, el epitelio mucoso, las células endoteliales venosas y arteriales tuvieron una importante expresión de AQP1, sin embargo, AQP2 mostró una reacción positiva difusa menor, lo que sugiere que la AQP1 podría tener una función principal en la absorción y transporte de líquido en el sistema hepatobiliar del Lagarto Qinghai.

Expression of aquaporin 2, aquaporin 3 and aquaporin 4 in renal medulla of Bactrian camel ( Camelus bactrianus ) / Expresión de acuaporina 2, acuaporina 3 y acuaporina 4 en la médula renal del camello bactriano ( Camelus bactrianus )

SUMMARY: Aquaporins (AQPs) are members of the aquaporin water channel family that play an important role in reabsorption of water from the renal tubular fluid to concentrate urine. Using immunohistochemical staining on paraffin sections, We studied expression of AQP2, AQP3 and AQP4 in renal medulla of Bactrian camel (Camelus bactrianus). The renal medulla of cattle (Bos taurus) acted as the control. Compared with the control, strong expression of AQP2 was observed at the apical plasma membrane and intracellular vesicles, in both the outer medullary collecting duct (OMCD) and the inner medullary collecting duct (IMCD) of camel. Strong expression of AQP3 was observed at the basolateral plasma membrane of the IMCD of camel. Strong AQP4 expression, however, was observed at the basolateral plasma membrane in the OMCD of camel. Moreover, moderate AQP4 expression was detected in endothelium of capillary in medullary region of camels, whereas very weak/absent expression was detected in endothelium of capillary of cattle. We concluded that expression of AQP2, AQP3 and AQP4 in the camel kidney showed some differences from cattle in renal trans-epithelial water transport. It may enhance our better understanding of special water metabolism mechanisms that enable camels to survive in extreme environments.

RESUMEN: Las acuaporinas (AQP) son miembros de las proteínas de transporte que desempeñan un papel importante en la reabsorción de agua del líquido tubular renal para concentrar la orina. Estudiamos la expresión de AQP2, AQP3 y AQP4 en la médula renal del camello bactriano (Camelus bactrianus) usando tinción inmunohistoquímica en secciones de parafina. La médula renal del bovino (Bos taurus) se usó como control. En comparación con el control, se observó una fuerte expresión de AQP2 en la membrana plasmática apical y vesículas intracelulares tanto en el conducto colector medular externo (CCME) como en el conducto colector medular interno (CCMI) del camello. Se observó una fuerte expresión de AQP3 en la membrana plasmática basolateral del CCMI del camello. También se observó una expresión fuerte de AQP4 en la membrana plasmática basolateral en el CCME de camello. Además, se detectó una expresión moderada de AQP4 en el endotelio de los capilares en la región medular de los camellos, mientras que en el endotelio de los capilares del bovino se detectó una expresión muy débil. Concluimos que la expresión de AQP2, AQP3 y AQP4 en el riñón de camello mostró algunas diferencias con el bovino en el transporte trans-epitelial de agua renal. El estudio podría mejorar nuestra comprensión de los mecanismos especiales del metabolismo del agua que permiten a los camellos sobrevivir en ambientes extremos.

Regulation of aquaporins in plants under stress

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.

Adecuación en diálisis peritoneal pediátrica: Del test de equilibrio peritoneal a las aquaporinas / Peritoneal dialysis adequacy in pediatrics: From the peritoneal equilibration test to the aquaporins

La evaluación de las características de transporte de solutos y agua del peritoneo es esencial para adecuar la prescripción dialítica en pacientes portadores de enfermedad renal crónica. Existen una serie de modelos para realizar esta evaluación. El test de equilibrio peritoneal (PET) evalúa la capacidad de transporte del peritoneo clasificando a los pacientes en 4 categorías de transportador: alto, promedio alto, promedio bajo y bajo. El short PET realiza la misma evaluación en solo 2 h, y ha sido validado en pacientes pediátricos. Por otro lado, el MiniPET otorga información adicional al evaluar la capacidad de transporte de agua libre por los poros ultrapequeños, y el Accelerated Peritoneal Examination Time (APEX) evalúa el punto de intersección de las curvas de equilibrio de urea y glucosa, y ha sido propuesto como el tiempo de permanencia óptimo para lograr una UF adecuada. Se analiza la información actual sobre estos métodos diagnósticos, en particular los últimos aportes de la literatura respecto al transporte de agua libre vía aquaporinas, que podrían representar una herramienta importante para optimizar el transporte de agua y solutos en pacientes en diálisis peritoneal crónica, en particular respecto al pronóstico cardiovascular.

An evaluation of the characteristics of peritoneal solute and water transport is essential to assess the suitability of prescribing dialysis in patients suffering from chronic renal disease. There are currently a series of models to perform this evaluation. The peritoneal equilibration test (PET) evaluates the peritoneal transport capacity, classifying the patients into four transport categories: high, high-average, low-average, and low. The short PET enables the same evaluation to be made in only 2 hours, and has been validated in paediatric patients. On the other hand, the MiniPET provides additional information by evaluating the free water transport capacity by the ultra-small pores, and the Accelerated Peritoneal Examination Time (APEX) evaluates the time when the glucose and urea equilibration curves cross, and has been proposed as the optimum dwell time to achieve adequate ultrafiltration. An analysis is presented on the current information on these diagnostic methods as regards free water transport via aquaporins, which could be an important tool in optimising solute and water transport in patients on chronic peritoneal dialysis, particularly as regards the cardiovascular prognosis.

Agmatine Attenuates Brain Edema and Apoptotic Cell Death after Traumatic Brain Injury

Traumatic brain injury (TBI) is associated with poor neurological outcome, including necrosis and brain edema. In this study, we investigated whether agmatine treatment reduces edema and apoptotic cell death after TBI. TBI was produced by cold injury to the cerebral primary motor cortex of rats. Agmatine was administered 30 min after injury and once daily until the end of the experiment. Animals were sacrificed for analysis at 1, 2, or 7 days after the injury. Various neurological analyses were performed to investigate disruption of the blood-brain barrier (BBB) and neurological dysfunction after TBI. To examine the extent of brain edema after TBI, the expression of aquaporins (AQPs), phosphorylation of mitogen-activated protein kinases (MAPKs), and nuclear translocation of nuclear factor-kappaB (NF-kappaB) were investigated. Our findings demonstrated that agmatine treatment significantly reduces brain edema after TBI by suppressing the expression of AQP1, 4, and 9. In addition, agmatine treatment significantly reduced apoptotic cell death by suppressing the phosphorylation of MAPKs and by increasing the nuclear translocation of NF-kappaB after TBI. These results suggest that agmatine treatment may have therapeutic potential for brain edema and neural cell death in various central nervous system diseases.

Time-Dependent Expression Patterns of Cardiac Aquaporins Following Myocardial Infarction

Aquaporins (AQPs) are expressed in myocardium and the implication of AQPs in myocardial water balance has been suggested. We investigated the expression patterns of AQP subtypes in normal myocardium and their changes in the process of edema formation and cardiac dysfunction following myocardial infarction (MI). Immunostaining demonstrated abundant expression of AQP1, AQP4, and AQP6 in normal mouse heart; AQP1 in blood vessels and cardiac myocytes, AQP4 exclusively on the intercalated discs between cardiac myocytes and AQP6 inside the myocytes. However, neither AQP7 nor AQP9 proteins were expressed in CD1 mouse myocardium. Echocardiography revealed that cardiac function was reduced at 1 week and recovered at 4 weeks after MI, whereas myocardial water content determined by wet-to-dry weight ratio increased at 1 week and rather reduced below the normal at 4 weeks. The expression of cardiac AQPs was up-regulated in MI-induced groups compared with sham-operated control group, but their time-dependent patterns were different. The time course of AQP4 expression coincided with that of myocardial edema and cardiac dysfunction following MI. However, expression of both AQP1 and AQP6 increased persistently up to 4 weeks. Our findings suggest a different role for cardiac AQPs in the formation and reabsorption of myocardial edema after MI.

Aquaporin 9 in rat brain after severe traumatic brain injury / Aquaporina 9 em cérebro de rato após traumatismo cerebral grave

OBJECTIVE: To reveal the expression and possible roles of aquaporin 9 (AQP9) in rat brain, after severe traumatic brain injury (TBI). METHODS: Brain water content (BWC), tetrazolium chloride staining, Evans blue staining, immunohistochemistry (IHC), immunofluorescence (IF), western blot, and real-time polymerase chain reaction were used. RESULTS: The BWC reached the first and second (highest) peaks at 6 and 72 hours, and the blood brain barrier (BBB) was severely destroyed at six hours after the TBI. The worst brain ischemia occurred at 72 hours after TBI. Widespread AQP9-positive astrocytes and neurons in the hypothalamus were detected by means of IHC and IF after TBI. The abundance of AQP9 and its mRNA increased after TBI and reached two peaks at 6 and 72 hours, respectively, after TBI. CONCLUSIONS: Increased AQP9 might contribute to clearance of excess water and lactate in the early stage of TBI. Widespread AQP9-positive astrocytes might help lactate move into neurons and result in cellular brain edema in the later stage of TBI. AQP9-positive neurons suggest that AQP9 plays a role in energy balance after TBI.

OBJETIVO: Revelar a expressão e os possíveis papéis da aquaporina 9 (AQP9) no cérebro de ratos após lesão cerebral traumática (LCT) grave. MÉTODOS: Foram utilizados: determinação do conteúdo cerebral de água, corante cloreto de tetrazólio, corante azul de Evans, imunoistoquímica (IHQ), imunofluorescência (IF), western blot e PCR em tempo real. RESULTADOS: O conteúdo cerebral de água alcançou o primeiro e o segundo (o mais alto) picos após 6 e 72 horas. A função da barreira hematoencefálica se mostrou muito prejudicada após 6 horas da LCT. A pior isquemia cerebral ocorreu após 72 horas da LCT. Astrócitos AQP9 positivos e neurônios no hipotálamo foram detectados difusamente pela IHQ e IF após LCT. A abundância de AQP9 e de sua mRNA aumentou após LCT e alcançou dois picos após 6 e 72 horas, respectivamente, da LCT. CONCLUSÕES: AQP9 aumentada pode contribuir para a eliminação de água e lactato em excesso na fase precoce da LCT. Astrócitos difusamente localizados AQP9 positivos podem ajudar a entrada do lactato nos neurônios, promovendo edema cerebral celular na fase tardia da LCT. Neurônios AQP9 positivos sugerem que AQP9 tem um papel no equilíbrio energético após LCT.

Enhanced expression of aquaporin-9 in rat brain edema induced by bacterial lipopolysaccharides / 华中科技大学学报（医学）（英德文版）

To investigate the role of AQP9 in brain edema, the expression of AQP9 in an infectious rat brain edema model induced by the injection of lipopolysaccharide (LPS) was examined. Immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) analysis demonstrated that the expressions of AQP9 mRNA and protein at all observed intervals were significantly increased in LPS-treated animals in comparison with the control animals. Time-course analysis showed that the first signs of blood-brain barrier disruption and the increase of brain water content in LPS-treated animals were evident 6 h after LPS injection, with maximum value appearing at 12 h, which coincided with the expression profiles of AQP9 mRNA and protein in LPS-treated animals. The further correlation analysis revealed strong positive correlations among the brain water content, the disruption of the blood-brain barrier and the enhanced expressions of AQP9 mRNA and protein in LPS-treated animals. These results suggested that the regulation of AQP9 expression may play important roles in water movement and in brain metabolic homeostasis associated with the pathophysiology of brain edema induced by LPS injection.

Expression of water channel protein 1 in the lung of the drown rat / 法医学杂志

OBJECTIVE@#To determine the expression of water channel 1 protein in the lung of drown rat and that of after death thrown into the water.@*METHODS@#Immunohistochemical method was used and the computer image analysis was conducted to detect the distribution of AQP1.@*RESULTS@#The positive expression of AQP1 was seen in the capillary endotheliocyte of the interstitial and around bronchi and in the alveolar endothelial cells. The value of intergrated optical density was statistical significant.@*CONCLUSION@#It suggests that AQP1 is one of sensitive signs to distinguish ante-mortem and postmortem immersion.

Aquaporin water channels in exocrine glands

No abstract available.