Based on Histogram Analysis: ADCaqp Derived from Ultra-high b-Value DWI could be a Non-invasive Specific Biomarker for Rectal Cancer Prognosis.

Aquaporins (AQP) are not only water channel protein, but also potential prognostic indicator and therapeutic target for rectal cancer. Some previous studies have demonstrated the AQP expression could be estimated by ADCaqp value derived from ultra-high b-value diffusion-weighted imaging (DWI). We aim to determine whether ADCaqp could be a new and specific biomarker for indicating the AQP expression and prognostic factors of rectal cancer. 76 untreated patients with rectal cancer confirmed by colonoscopy biopsy were enrolled. ADCaqp value was generated from ultra-high b-value DWI with five b-values (1700-3500 s/mm2). AQP (AQP1, 3 and 5)staining intensity was estimated by both of software (QuPath) and manual manner. The relationships between histogram features of ADCaqp and AQP staining intensity were analyzed. The correlations between histogram features of ADCaqp and differentiation degrees (good, moderate, poor), T stage (T1-2 vs T3-4), and lymph node status (N+ vs N-) were also evaluated respectively. The mean, 75th percentile and 97.5th percentile of ADCaqp were correlated with AQP1 staining intensity (r = 0.237, 0.323 and 0.362, respectively, all P < 0.05) . No correlation was found between the histogram features of ADCaqp and AQP3 or AQP5 staining intensity. The mean, 50th percentile, 75th percentile and 97.5th percentile of ADCaqp value exhibited significant differences between differentiation status (all P < 0.05). Histogram features of ADCaqp value showed no significant differences in two subgroups of T stage and lymph node status (all P > 0.05). Histogram analysis showed that the ADCaqp value derived from ultra-high b-value DWI of rectal cancer could reflect AQP1's expression and rectal cancer's malignancy degree. ADCaqp might be a new imaging biomarker for evaluating rectal cancer.

Characterization of the circadian oscillator in the choroid plexus of rats.

Circadian rhythms are a fundamental biological phenomena that control various physiological functions. The suprachiasmatic nucleus (SCN) is a master clock that integrates various peripheral clocks. Recently, the choroid plexus (CP) was reported to be one such peripheral clock, a circadian oscillator that might conversely affect the SCN. Hence, the principle aim of our study was to unravel the circadian oscillator within the CP. Quantitative PCR against rPer1, rPer2, and rBmal1 showed that CP in the lateral ventricle (CP-LV) and fourth ventricle (CP-4V) has a robust circadian oscillator. The phases of the CP oscillator are between those of the pineal gland (PG) and SCN. Bioluminescence monitoring of explants showed that the intrinsic circadian period of CP-LV and CP-4V was approximately 21 h, which is shorter than SCN and PG. It is possible that interaction between oscillators of the CP-LV, CP-4V, PG, and SCN ensures the SCN adopts a stable 24 h rhythm, with each of the regions having an intrinsic oscillator with different phases and periods. In situ hybridization analysis revealed that dusk-to-dawn variation of rPer2 expression was found in epithelial cells of the CP only. Furthermore, the CP circadian oscillator might control cerebrospinal fluid secretion. However, no dusk-to-dawn variation in expression of the water channel, aquaporin 1, was observed. Further investigations are needed to clarify the involvement of circadian rhythm on CP.

Significant enhanced expressions of aquaporin-1, -4 and -9 in the brains of various prion diseases.

Aquaporins (AQPs) are widely expressed in various types of tissues, among them AQP1, AQP4 and AQP9 are expressed predominately with relatively special distributing features in various brain regions. The aberrant changes of AQP1 and AQP4 have been observed in the brains of Alzheimer disease (AD). To evaluate the underlying alteration of brain AQPs in prion diseases, scrapie strains of 139A, ME7 and S15 infected mice were tested in this study. Western blots revealed markedly increased levels of AQP1, AQP4 and AQP9 in the brain tissues of all tested scrapie-infected mice collected at terminal stage. Analyses of the AQPs levels in the brain tissues collected at different time-points during incubation period showed time-dependent increased in 139A and ME7-infected mice, especially at the middle-late stage. The AQP1 levels also increased in the cortex regions of some human prion diseases, including the patients with sporadic Creutzfeldt-Jakob disease (CJD), fatal familial insomnia (FFI) and G114V genetic CJD (gCJD). Immunohistochemistry (IHC) assays verified that the AQPs-positive cells were astrocyte-like morphologically; meanwhile, numerous various sizes of AQPs-positive particles and dots were also observable in the brain sections of scrapie-infected mice. Immunofluorescent assays (IFAs) illustrated that the signals of AQPs colocalized with those of the GFAP positive proliferative astrocytes, and more interestingly, appeared to overlap also with the signals of PrP in the brains of scrapie-infected mice. Moreover, IHC assays with a commercial doublestain system revealed that distributing areas of AQPs overlapped not only with that of the activated large astrocytes, but also with that of abundantly deposited PrPSc in the brain tissues of scrapie murine models. Our data here propose the solid evidences that the expressions of brain AQP1, AQP4 and AQP9 are all aberrantly enhanced in various murine models of scrapie infection. The closely anatomical association between the accumulated AQPs and deposited PrPSc in the brain tissues indicates that the abnormally increased water channel proteins participate in the pathogenesis of prion diseases.

Distribution of aquaporins and sodium transporters in the gastrointestinal tract of a desert hare, Lepus yarkandensis.

Lepus yarkandensis is a desert hare of the Tarim Basin in western China, and it has strong adaptability to arid environments. Aquaporins (AQPs) are a family of water channel proteins that facilitate transmembrane water transport. Gastrointestinal tract AQPs are involved in fluid absorption in the small intestine and colon. This study aimed to determine the distribution of AQPs and sodium transporters in the gastrointestinal tract of L. yarkandensis and to compare the expression of these proteins with that in Oryctolagus cuniculus. Immunohistochemistry was performed to analyse the cellular distribution of these proteins, and the acquired images were analysed with IpWin32 software. Our results revealed that AQP1 was located in the colonic epithelium, central lacteal cells, fundic gland parietal cells, and capillary endothelial cells; AQP3 was located in the colonic epithelium, small intestinal villus epithelium, gastric pit and fundic gland; AQP4 was located in the fundic gland, small intestinal gland and colonic epithelium; and epithelial sodium channel (ENaC) and Na+-K+-ATPase were located in the epithelial cells, respectively. The higher expression levels of AQP1, AQP3, ENaC and Na+-K+-ATPase in the colon of L. yarkandensis compared to those in O. cuniculus suggested that L. yarkandensis has a higher capacity for faecal dehydration.

Immunohistochemical identification of AQP1 in livers of the high-fat diet rats / Identificación inmunohistoquímica de AQP1 en hígados de ratas con dieta de alto contenido de grasa

One of the key functions of the hepatobiliary system is bile formation. Aquaporins (AQPs) are likely to play a role in water transport that is essential for appropriate hepatobiliary tract function. The increasing prevalence of fatty liver parallels the rise of obesity and its complications over the past several decades. In this paper, general morphology observation, histopathology and AQP1 immunohistochemical expression were observed in livers of the high-fat diet (HFD) rats. For the liver of HFD rats, immunolight microscopy revealed weak labeling of AQP1 on the surface of central veins and liver sinusoid compared with the normal diet (ND) rats. It was suggested that bile secreted by the liver of HFD rats was maybe abnormal, thereby causing abnormalities in the composition and secretion of bile. However, the deeper understanding of mechanisms involved to the fatty liver is still unclear, in particular AQPs in the liver of obesity, additional studies would be required to study the signalling cascades involved in these processes.

Una de las funciones clave del sistema hepatobiliar es la formación de bilis. Es probable que las acuaporinas (AQP) desempeñen un papel en el transporte de agua que es esencial para la función apropiada del tracto hepatobiliar. En las últimas décadas, la creciente prevalencia de hígado graso es paralela al aumento de la obesidad y sus complicaciones. En este trabajo, se identificaron características morfológicas generales, histopatología y expresión inmunohistoquímica de AQP1 en hígados de ratas con dieta rica en grasas (DRG). En el hígado de ratas con DRG, la expresión inmunohistoquímica determinó un marcaje débil de AQP1 en la superficie de las venas centrales y del sinusoide hepático en comparación con las ratas de dieta normal (DN). Se sugirió que la bilis secretada por el hígado de ratas con DRG era tal vez anormal, lo que causaba anomalías en la composición y secreción de la bilis. Sin embargo, se necesita un conocimiento mayor de los mecanismos involucrados en el hígado graso, en particular de las AQP y se requieren estudios adicionales para determinar las cascadas de señalización involucradas en estos procesos.

The Effect of Aquaporin 1-Inhibition on Vasculogenic Mimicry in Malignant Mesothelioma.

Malignant mesothelioma (MM) is an aggressive malignancy of the serosal membranes, with poor overall survival and quality of life. Limited targeted treatment strategies exist due to restricted knowledge of pathogenic pathways. Vasculogenic mimicry (VM) is a newly described phenomenon associated with increased aggressiveness in other malignancies, and has been characterized in MM. Normal mesothelium expresses aquaporin 1 (AQP1) and retained expression has been associated with improved survival in MM. AQP1 is expressed by normal vascular endothelium and is involved in mediating MM cell motility and proliferation. We investigated the role of AQP1 in VM, and its interaction with the pro-angiogenic factor vascular endothelial growth factor A (VEGFA), which is variably expressed in MM. Matrigel VM assays were performed using NCI-H226 and NCI-H28 MM cell lines and primary cells in hypoxia and normoxia. The synthetic blocker AqB050 and siRNA were used to inhibit AQP1, and bevacizumab was used to inhibit VEGF. Inhibition of AQP1 resulted in increased VEGFA secretion by MM cells and reduced VM in MM cell lines in hypoxia but not normoxia. No change in VM was seen in MM primary cells. Combined inhibition of AQP1 and VEGF had no effect on VM in normoxia. In a heterotopic xenograft mouse model, AqB050 treatment did not alter vessel formation. AQP1 may interact with VEGFA and play a role in VM, especially under hypoxic conditions, but the heterogeneity of MM cells may result in different dominant pathways between patients.

PPAR­Î³ agonist rosiglitazone protects rat peritoneal mesothelial cells against peritoneal dialysis solution­induced damage.

Long-term peritoneal dialysis (PD) leads to ultrafiltration failure (UFF). Peritoneal mesothelial cells, which form the innermost monolayer of the peritoneal cavity, have been shown to regulate various responses, including inflammation, in UFF. The present study was designed to investigate the effect of the peroxisome proliferator­activated receptor­Î³ (PPAR­Î³) agonist, rosiglitazone, on peritoneal dialysis solution (PDS)­induced injuries in rat peritoneal mesothelial cells (RPMCs). RPMCs were cultured for different durations and with different concentrations of PDS. The gene expression levels of aquaporin­1 (AQP­1) and zonula occluden­1 (ZO­1) were determined using reverse transcription­quantitative polymerase chain reaction analysis. The protein levels of AQP­1, ZO­1 and PPAR­Î³ were measured using western blot analysis. Interleukin (IL)­6 and IL­8 were detected using ELISA. The RPMCs were damaged by stimulation with 4.25% PDS for 72 h. The expression levels of AQP­1 and ZO­1 were increased, and the secretion of IL­6 and IL­8 were decreased by rosiglitazone. The use of the PPAR­Î³ inhibitor, GW­9662, completely prevented the effects of rosiglitazone. These results indicated that PDS exposure stimulated an inflammatory response in the RPMCs. The PPAR­Î³ activator, rosiglitazone, appeared to relieve the injury by inhibiting inflammation, and regulating the expression of AQP­1 and ZO­1, however further investigations are required to elucidate the potential underlying mechanism.

Aquaglyceroporin1 gene expression in antimony resistance and susceptible Leishmania major isolates.

BACKGROUND & OBJECTIVES: The mechanism of antimony resistance in Leishmania has been studied extensively, in connection with decreased influx and/or increased eflux of the drug. Aquaporin 1 (AQP1) protein has been shown to mediate the uptake of trivalent antimony. This study was aimed to find the expression level of AQP1 gene in resistant versus non-resistant clinical isolates of Leishmania major in Iranian patients. METHODS: Clinical isolates were obtained from 16 considered patients referred to Navab Safavi Clinical Center, Isfahan, Iran from October 2014 to December 2015. After diagnosis of cutaneous leishmaniasis using microscopic observation, biopsy was performed from lesion(s) of each patient and stored inside RNAlater solution at -20΀C. Written informed consent was obtained from all the patients to participate in the study before recording their information and sampling based on Helsinki declaration. Each patient was treated with Glucantime and followed for three months. All sensitive and resistance isolates were considered and compared with AQP1 gene expression using real time PCR that was analyzed with delta-delta Ct. RESULTS: Out of 16 clinical isolates, four patients were resistant and 12 were non-resistant. The AQP1 gene expression in resistant isolates was significantly higher than the one in response failure isolates (p = 0.001). INTERPRETATION & CONCLUSION: The significant over expression (0.5 fold) of AQP1 gene in resistant versus non- resistant isolates suggests different mechanism of drug resistance such as mutations. Mutations may change the physiological function of the Aquaporin 1 protein that might affect its expression level.

Descending thin limb of the intermediate loop expresses both aquaporin 1 and urea transporter A2 in the mouse kidney.

A new intermediate type of Henle's loop has been reported that it extends into the inner medulla and turns within the first millimeter beyond the outer medulla. This study aimed to identify the descending thin limb (DTL) of the intermediate loop in the adult C57Bl/6 mouse kidney using aquaporin 1 (AQP1) and urea transporter A2 (UT-A2) antibodies. In the upper part of the inner stripe of the outer medulla (ISOM), AQP1 was expressed strongly in the DTL with type II epithelium of the long loop, but not in type I epithelium of the short loop. The DTL of the intermediate loop exhibited weak AQP1 immunoreactivity. UT-A2 immunoreactivity was not observed in the upper part of any DTL type. AQP1 expression was similar in the upper and middle parts of the ISOM. UT-A2 expression was variable, being expressed strongly in the DTL with type I epithelium of the short loop, but not in type II epithelium of the long loop. In the innermost part of the ISOM, AQP1 was expressed only in type III epithelium of the long loop. UT-A2-positive and UT-A2-negative cells were intermingled in type I epithelium of the intermediate loop, but were not observed in type III epithelium of the long loop. UT-A2-positive DTLs of the intermediate loop extended into the UT-A2/AQP1-negative type I epithelium in the initial part of the inner medulla. These results demonstrate that the DTL of the intermediate loop is composed of type I epithelium and expresses both AQP1 and UT-A2. The functional role of the DTL of the intermediate loop may be distinct from the short or long loops.

Morphology and Aquaporin Immunohistochemistry of the Uterine Tube of Saanen Goats (Capra hircus): Comparison Throughout the Reproductive Cycle.

The expression of six different aquaporins (AQP1, 2, 3, 4, 5 and 9), integral membrane water channels that facilitate bi-directional passive movement of water, was investigated by immunohistochemistry in the uterine tube of pre-pubertal and adult Saanen goats (Capra hircus), comparing the different phases of the oestrous cycle. Regional morphology and secretory processes were markedly different during the goat oestrous cycle. The tested AQP molecules showed different expression patterns in comparison with already studied species. AQP1-immunoreactivity was evidenced at the endothelium of blood vessels and in nerve fibres, regardless of the tubal tract and cycle period. AQP4-immunoreactivity was shown on the lateral plasmalemma in the basal third of the epithelial cells at infundibulum and ampulla level in the cycling goats, more evidently during follicular than during luteal phase. No AQP4-immunoreactivity was noticed at the level of the isthmus region, regardless of the cycle phase. AQP5-immunoreactivity, localized at the apical surface of epithelial cells, increased from pre-puberty to adulthood. Thereafter, AQP5-immunoreactivity was prominent during the follicular phase, when it strongly decorated the apical plasmalemma of all epithelial cells at ampullary level. During luteal phase, immunoreactivity was discontinuous, being weak to strong at the apex of the secretory cells protruding into the lumen. In the isthmus region, the strongest AQP5-immunoreactivity was seen during follicular phase, with a clear localization in the apical plasmalemma of all the epithelial cells and also on the lateral plasmalemma. AQP2, 3 and 9 were undetectable all along the goat uterine tube. Likely, a collaboration of different AQP molecules sustains the fluid production in the goat uterine tube. AQP1-mediated transudation from the blood capillaries, together with permeation of the epithelium by AQP4 in the basal rim of the epithelial cells and final intervening of apical AQP5, could be involved in fluid production as well as in secretory processes.

Increased aquaporin 1 expression in the tunica albuginea of Peyronie's disease patients: an in vivo pilot study.

Peyronie's disease (PD) is a localized disorder of the connective tissue of the tunica albuginea (TA) whose etiology has not been elucidated. Although several studies have implicated genetic susceptibility and/or mechanical trauma as triggering events for PD, the underlying molecular mechanisms remain largely unknown. Aquaporin 1 (AQP1) is a water channel protein potentially implicated in connective tissue resistance to mechanical stress, acting primarily by increasing tension within the collagen network. Although it represents a potentially attractive molecular target in PD, to date no studies had ever addressed whether AQP1 is detectable and/or differentially expressed in the TA of these patients. Herein the present study, through immunohistochemical and biochemical approaches, we were able to detect AQP1 expression in the TA of control and PD affected patients. We demonstrated that AQP1-like immunoreactivity and expression are significantly increased in plaques of PD patients Vs controls, implying that AQP1 overexpression might be the consequence of a localized maladaptive response of the connective tissue to repeated mechanical trauma. In summary, these data support the idea that AQP1 might represent a potentially useful biomarker of mechanical injury in the TA and a promising target for the treatment of PD.

Expression of AQP1 Was Associated with Apoptosis and Survival of Patients in Gastric Adenocarcinoma.

RATIONALE AND OBJECTIVE: Recently, interest in the role of aquaporin 1 (AQP1) in human gastrointestinal carcinogenesis has developed. However, to date no studies have examined relationships between AQP1 expression and specific characteristics of gastric adenocarcinoma. METHODS: We investigated 109 specimens of primary gastric adenocarcinoma and their corresponding normal gastric mucosa using immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) to determine AQP1 expression. We then evaluated disease free survival (DFS) and overall survival (OS) in these patients in association with AQP1 expression. RESULTS: Both immunohistochemical and RT-PCR analyses identified increased AQP1 expression in tumors from patients with gastric adenocarcinoma (p < 0.001). The 3-year DFS and OS rates were higher in the AQP1-negative group than in the positive group (DFS: 77.2 vs. 52.8%, p < 0.001; OS: 85.1 vs. 70.7%, p < 0.001). The 5-year DFS and OS rates exhibited a similar trend (p < 0.001). Subgroup analysis of patients with early gastric adenocarcinoma (stages I and II) revealed a total 5-year OS of 90.0%, with 5-year OS being higher in the AQP1-negative group than in the positive group (95.2 vs. 84.2%). Furthermore, incidence of tumor recurrence following surgical treatment was significantly higher in the AQP1-positive group (4/19, 21.1%) compared with the negative group (0/21, 0%). CONCLUSIONS: Our study demonstrates that AQP1 plays an important role in gastric adenocarcinoma and may therefore represent a novel therapeutic target and prognostic marker in this disease.

Immunolocalization of Aquaporins 1 and 9 in the Ram Efferent Ducts and Epididymis.

Aquaporins (AQPs) are essential membrane protein channels for the transport of water across membranes. Fluid movement in the epididymis is important for modulation of the luminal environment, in which sperm mature and reside. This study was designed to understand the morphology and localization of AQPs in ram efferent ducts (ED) and epididymis. For this purpose, the epididymis of seven animals were removed for histologic and immunohistochemical analyses. AQP1 immunoreactivity was observed in the apex of the ED, and AQP9 was found adjacent to the nuclei of the epithelial cells of the ED. The epithelial lining of ram epididymis is pseudostratified columnar and presents principal, basal, apical and narrow cells. In the initial segment (IS), a moderate reaction for AQP1 was observed in the apical cytoplasm of epithelial cells. An intense reactivity for AQP1 was noted over the microvilli of principal cells and in spermatozoa in the caput. In the corpus and cauda, AQP1 was noted only over the endothelial cells of vascular channels located in intertubular spaces. A weak-to-moderate reaction for AQP9 was observed in the nuclei of epithelial cells in the IS, caput and corpus of the epididymis. In the cauda, an intense reaction to AQP9 was observed in the epithelial border. In the IS, caput and corpus, the reactivity for AQP9 differed from those observed in domestic animals. The cauda showed a pattern similar to that previously described. These results indicate that AQPs 1 and 9 have reversed locations and roles in rams, suggesting activity variations related with fluid and solute absorption throughout the epididymis.

Use of aquaporins 1 and 5 levels as a diagnostic marker in mild-to-moderate adult-onset asthma.

Characteristic features of asthma include airway inflammation and hyperactivity, mucus hypersecretion, mucosal edema, and airway remodeling. These features could be due to pathological water transport across pulmonary epithelia and aquaporins (AQPs) have recently been isolated as key proteins in fluid transportation in the human respiratory tract. We aimed to evaluate the role of aquaporins in the pathogenesis of asthma and their possible use a diagnostic marker of the disease. A total of 110 hospitalized and outpatients with mild to moderate adult-onset asthma were invited to participate in this study and 34 submitted an induced sputum sample adequate for analysis. The amount of AQP1, AQP5 and MUC5AC were measured with ELISA assay. The amount of IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ and IL-17 in both serum and sputum were measured with Cytometry Bead Array (CBA kit). Our results suggest that sputum AQP5, AQP1 and MUC5AC are all in a good correlation (r=0.498 between AQP5 and AQP1, r=0.529 and r=0.661 between MUC5AC and AQP5 or AQP1, respectively, all P<0.05). The AUC value for AQP1 and AQP5 to diagnose asthma were 0.729 and 0.745, respectively. In conclusion, water homeostasis plays an important role in maintaining adequate fluid transportation within the lung and is involved in the pathogenesis of asthma. Our results suggest that AQP may influence pulmonary physiology that their dysfunction can contribute to pulmonary pathogenesis, such as asthma. Moreover, their quantification could serve as biomarkers for the diagnosis of asthma.

Ductuli efferentes of the male Golden Syrian hamster reproductive tract.

Efferent ductules are responsible for the transportation of spermatozoa from the testis to the epididymis and their epithelium is responsible for the reabsorption of over 90% of the luminal fluid. The purpose of this research was to characterize the gross morphology and histology of efferent ductules in the male Golden Syrian hamster. The efferent ductules emerge from rete testis with a unique polarity at the apex or cephalic pole of the testis. The number of efferent ductules varied from 3 to 10 with an average of 6.0 and blind ending ducts were observed in approximately 56% of the males. The ductules merged into a single common duct prior to entering the caput epididymidis. The proximal efferent ductule lumen was wider than the distal (conus and common ducts), consistent with reabsorption of most of the luminal fluid, as was morphology of the ductal epithelium. Non-ciliated cells in the proximal region had prominent endocytic apparatuses, showing both coated pits and apical tubules in the apical cytoplasm. Large basolateral, intercellular spaces were also present in the epithelium of the proximal region. Distal non-ciliated cells had an abundance of large endosomes and lysosomal granules. Localisation of sodium/hydrogen exchanger-3 (NHE3; SLC9A3) and aquaporins 1 and 9 (AQP1, AQP9) along the microvillus border was also consistent with ion transport and fluid reabsorption by this epithelium. In comparison, the caput epididymidis epithelium expressed only AQP9 immunostaining. Another unusual feature of the hamster efferent ductules was the presence of glycogen aggregates in the basal cytoplasm of small groups of epithelial cells, but only in the proximal ducts near the rete testis. Androgen (AR), estrogen (ESR1 and ESR2) and vitamin D receptors (VDR) were also abundant in epithelial nuclei of proximal and distal efferent ductules. In comparison, caput epididymidis showed very little immunostaining for ESR1.

Calcium signaling and cell volume regulation are altered in Sjögren's Syndrome.

OBJECTIVE: Sjögren's Syndrome (SS) is a chronic autoimmune disease, leading to deficient secretion from salivary and lacrimal glands. Saliva production is normally increased by cholinergic innervation, giving rise to intracellular calcium signaling and water transport through water channels (aquaporins, AQPs). The aim of this study was to investigate possible pathophysiological changes in cell volume regulation, AQP expression and localization, and intracellular calcium signaling in glandular cells from SS patients compared to controls. MATERIALS AND METHODS: A total of 35 SS patients and 41 non-SS controls were included. Real time qPCR was combined with immunohistochemistry to analyze the mRNA expression and cellular distribution of AQP1, 3 and 5. Cell volume regulation and intracellular calcium signaling were examined in fresh acinar cells. RESULTS: We show for the first time a reduced mRNA expression of AQP1 and 5 in SS compared to controls, accompanied by a decrease in staining intensity of AQP1, 3 and 5 in areas adjacent to local lymphocytic infiltration. Furthermore, we observed that the SS cells' capacity for volume regulation was abnormal. Similarly, the calcium response after parasympathetic agonist (carbachol) stimulation was markedly decreased in SS cells. CONCLUSIONS: It is concluded that mRNA expression of AQP1 and 5, protein distribution of AQP1, 3 and 5, glandular cell volume regulation and intracellular calcium signaling are all altered in SS, pointing to possible pathophysiological mechanisms in SS.

Immunolocalization of aquaporin water channels in the domestic cat male genital tract.

Four different aquaporins (AQP1, 2, 5 and 9), integral membrane water channels that facilitate rapid passive movement of water, were immuno-localized in the excurrent ducts collected from sexually mature cats during orchiectomy. Aquaporins 1, 2 and 9, were immuno-localized at distinct levels, whereas AQP5 was undetectable all along the feline genital tract. No immunoreactivity was present at the level of the rete testis with any of the antibodies tested. In the efferent ducts, AQP1-immunoreactivity was strongly evidenced at the apical surface of the non-ciliated cells, and AQP9-immunoreactivity was shown at the periphery of both ciliated and non-ciliated cells. Aquaporins 2 was absent in the caput epididymidis, either in the efferent ducts or in the epididymal duct. Otherwise, AQP2 was increasingly localized at the adluminal surface of principal cells from the corpus to the cauda epididymidis and more weakly in the vas deferens epithelium. The supranuclear zone of the epididymal principal cells was AQP9-immunoreactive throughout the duct, with the exclusion of the vacuolated sub-region of the caput and with higher reaction intensity in the cauda region. AQP1 was present in the blood vessels all along the genital tract. AQP1 was expressed also in the smooth muscle layer of the vas deferens. The tested AQP molecules showed a different expression pattern in comparison with laboratory mammals, primates and the dog, unique other carnivore species studied to date. The present information is possibly useful in regard to the regional morphology of the feline epididymis and correlated functions, which are still a matter of debate.

Expresión de aquaporinas en tejido pulmonar de pacientes con enfermedad pulmonar obstructiva crónica / Aquaporin expression in the lung tissue of copd patients

INTRODUCCIÓN: Estudio de la expresión de aquaporinas (AQP1 y AQP5) en el tejido bronquial y parénquima pulmo-nar de pacientes con enfermedad pulmonar obstructiva cróni-ca (EPOC) y fumadores sin la enfermedad. MÉTODO: Utilizando un diseño caso-control, se seleccionó un grupo de 15 pacientes con EPOC (93,3% varones, con una edad media de 68 años, una media de FEV1 del 72% y 26,7% con corticosteroides inhalados) y 15 fumadores sin la enfermedad, a los cuales se les sometió a cirugía de resección pulmonar por neoplasia pulmonar. Se estudió la expresión de AQP1 y AQP5 en el tejido bronquial y en parénquima pulmo-nar mediante reacción en cadena de la polimerasa en tiempo real.RESULTADOS: No encontramos diferencias en la expresión génica de estas AQPs en ambos territorios pulmonares entre los pacientes con EPOC y los fumadores sin la enfermedad. Sin embargo, en los pacientes EPOC, la expresión de AQP1 era 2,41 veces mayor en el parénquima comparado con los controles, mientras que la AQP5 mostraba un patrón inverso, con 7,75 veces mayor expresión en el tejido bronquial de los sujetos control.CONCLUSIÓN: Los resultados del presente trabajo proporcio-nan evidencia inicial respecto a la expresión de AQP1 y AQP5 en pacientes con EPOC

INTRODUCTION: Study of aquaporin expression (AQP1 and AQP5) in the bronchial tissue and lung parenchyma of pa-tients with chronic obstructive pulmonary disease (COPD) and smokers without the disease. METHOD: Using a case-control design, a group of 15 patients with COPD was selected (93.3% males, with an average age of 68 years, an average FEV1 of 72% and 26.7% with inha-led corticosteroids) and 15 smokers without the disease, who underwent lung resection surgery due to lung neoplasm. The expression of AQP1 and AQP5 in the bronchial tissue and in lung parenchyma was studied using real-time polymerase chain reaction (PCR). RESULTS: No differences were found in the gene expression of these AQPs in either lung territories between the patients with COPD and the smokers without the disease. Nevertheless, in the COPD patients, the expression of AQP1 was 2.41 times greater in the parenchyma compared with the controls, while the AQP5 showed an inverse pattern, with 7.75 times greater expression in the bronchial tissue of the control subject. CONCLUSION: The results of this study provide initial evidence regarding the expression of AQP1 and AQP5 in patient with COPD

Expression analysis and clinical correlation of aquaporin 1 and 4 genes in human hippocampal sclerosis.

Mesial temporal sclerosis (MTS) is the most frequent cause of drug resistant symptomatic partial epilepsy. The mechanism and genetic background of this unique pathology are not well understood. Aquaporins (AQP) are regulators of water homeostasis in the brain and are expressed in the human hippocampus. We explored the role of AQP genes in the pathogenetic mechanisms of MTS through an evaluation of gene expression in surgically removed human brain tissue. We analyzed AQP1 and 4 mRNA levels by quantitative real-time polymerase chain reaction and normalized to ABL and cyclophilin genes, followed by immunohistochemistry for AQP4. Relative expressions were calculated according to the delta Ct method and the results were compared using the Mann-Whitney U test. Brain specimens of 23 patients with epilepsy who had undergone surgery for MTS and seven control autopsy specimens were investigated. Clinical findings were concordant with previous studies and 61% of the patients were seizure-free in the postoperative period. AQP1 and 4 gene expression levels did not differ between MTS patients and control groups. Immunofluorescence analysis of AQP4 supported the expression results, showing no difference. Previous studies have reported contradictory results about the expression levels of AQP in MTS. To our knowledge, only one study has suggested upregulation whereas the other indicated downregulation of perivascular AQP4. Our study did not support these findings and may rule out the involvement of AQP in human MTS.

Na-K-2Cl cotransporter and aquaporin 1 in arachnoid granulations, meningiomas, and meningiomas invading dura.

Meningioma invasion of the dura may contribute to the high rate of recurrence. Recently, ion channels that affect cell shape and movement have been implicated in cancer invasion. Combined Na-K-2Cl cotransporter (NKCC1) and aquaporin 1 (AQP1) expression in arachnoid granulations and meningiomas with and without dural invasion has not been characterized. Arachnoid granulations associated with dura were collected from 10 adult formalin-fixed dura/leptomeninges. Thirty-four frozen meningiomas were evaluated by Western blot. An additional 58 formalin-fixed, paraffin-embedded meningiomas including 36 World Health Organization grade I, 15 grade II, and 7 grade III meningiomas were evaluated by immunohistochemistry. By Western blot, NKCC1 was found in 17 (100%) of 17 World Health Organization grade I, 13 (87%) of 15 grade II, and both grade III meningiomas. Distinct AQP1 was not detected in the meningioma lysates tested. By immunohistochemistry, extensive NKCC1 but no AQP1 immunoreactivity was detected in the arachnoid granulation cells. Extensive NKCC1 was detected in meningioma cells in 56 and in capillaries in 43 by immunohistochemistry. In those tumors with dural or bone/soft tissue invasion, NKCC1 immunoreactivity was seen in invading cells in all cases and in their capillaries in the majority. AQP1 was detected in meningioma cells in 29 and in capillaries in all. AQP1 was also detected in cells and capillaries invading the dura or bone in 10 and 18 of 18, respectively. This was extensive in all subtypes of meningiomas studied. These findings suggest that NKCC1 and AQP1 participate in meningioma biology and invasion. NKCC1 might be targeted by FDA-approved NKCC1 inhibitors.