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.

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.

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.

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.

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.

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.

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.

Functions of aquaporin 1 and α-epithelial Na+ channel in rat acute lung injury induced by acute ischemic kidney injury.

PURPOSE: To establish a rat model of acute ischemic kidney injury by continually occluding the bilateral renal artery and renal veins, the functions of α-epithelial Na(+) channel (α-ENaC) and aquaporin (AQP1) in lung injury induced by acute kidney injury (AKI) were examined and compared with lung injury induced by endotoxin. METHODS: Male Wistar rats were randomly divided into three groups: control group, AKI group, and sepsis group. The concentrations of AQP1 and α-ENaC in the lung tissue were detected. The concentrations of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the serum and bronchoalveolar lavage fluid were also detected. RESULTS: The arterial blood pH in AKI group and PaO2 in sepsis group decreased 2 h after the experiment. A significant pulmonary interstitial and alveolar space edema, which showed a typical pathological change in acute lung injury, was found in AKI and sepsis group 8 h after the experiment. Two hours after the experiment, the concentration of TNF-α and IL-6 in the serum and bronchoalveolar lavage fluid (BALF) in AKI and sepsis group increased, whereas the pulmonary expression of AQP1 and α-ENaC decreased. The pulmonary AQP1 and α-ENaC of the rats were negatively correlated with TNF-α and IL-6 in BALF. The relevance among AQP1, α-ENaC, TNF-α, and IL-6 in sepsis group was higher than that in AKI group. CONCLUSION: The TNF-α and IL-6 levels increased significantly and the pulmonary expression of AQP1 and α-ENaC declined at the early stage of AKI.

Molecular pathology of pulmonary edema after injury in forensic autopsy cases.

The lung is vulnerable to trauma; pulmonary edema starts quickly as part of the systemic responses involved in shock. The present study investigated the molecular pathology of posttraumatic alveolar damage and responses involving pulmonary edema in forensic autopsy cases of injury (n = 66) compared with acute cardiac death cases (n = 13). Intrapulmonary mRNA and immunohistochemical expressions of matrix metalloproteinases (MMPs; MMP-2 and MMP-9), intercellular adhesion molecule-1, claudin-5, and aquaporins (AQPs, AQP-1 and AQP-5) were examined. Subacute injury deaths showed an increase in lung weight similar to that in acute cardiac death, but relative mRNA quantification using the Taqman real-time PCR assay demonstrated different findings among the causes of death; higher expressions were detected for all markers, except for AQP-5 in sharp instrument injury, for MMP-2 in blunt brain injury, and for MMP-9 in non-brain blunt injury, but these expression levels were lower in acute cardiac death. In immunostaining, only MMPs showed differences among the causes of death: MMP-2 expression was evident in most subacute deaths due to blunt brain injury and sharp instrument injury, whereas MMP-9 was intensely positive in those of non-brain blunt injury and sharp instrument injury. These findings suggest significant differences in the mechanism of pulmonary edema among fatal injuries and acute cardiac death, especially between blunt and sharp instrument injury. Systematic analysis of gene expressions using real-time PCR in combination with immunohistochemistry may be useful in evaluating pulmonary damage and responses after injury in death investigations, especially in connection with posttraumatic shock.

The expression of aquaporin 1 and 5 in uterine leiomyomata in premenopausal women: a preliminary study.

The aim of this study was to investigate the expression of aquaporins (AQPs) in uterine tissues of premenopausal women. We demonstrated for the first time the expression of AQP1, AQP5 and AQP9 in uterine leiomyomata and in the adjacent normal endometrium and myometrium. The expression of AQP1 and 5 was higher in leiomyomata than in unaffected uteri. AQP9 was expressed only in the unaffected endometrium. It is possible that AQP1 and AQP5 contribute to the formation of leiomyomata in premenopausal women.

The effect of allogenetic bone marrow-derived mesenchymal stem cell transplantation on lung aquaporin-1 and -5 in a rat model of severe acute pancreatitis.

BACKGROUND/AIMS: We aimed to determine the effect of transplantation on post- ALI (acute lung injury) edema in severe acute pancreatitis (SAP) and the expression levels of aquaporins -1 and -5 (AQP-1 and -5). METHODOLOGY: Sprague-Dawley (SD) rats were randomized into control-SAP and BMSCs-SAP groups. SAP model was prepared through retrograde injection of 5% taurocholic acid. BMSCs were isolated from the bone marrow of SD rats. We examined SAP rats for levels of IL-1ß and TNF-a, and for AQP-1 and -5 expression in lung tissues at 6 and 12 hours. RESULTS: The levels of IL-1ß and TNF-a in BMSC-SAP rats were lower than in control-SAP rats (both, p<0.001). Real-time RT-PCR analysis showed that AQP-1 mRNA expression in BMSC-SAP rats was higher than that in control-SAP rats (p=0.005 and p<0.001), and AQP-5 mRNA expression in BMSC-SAP rats was also higher than that in control-SAP rats (p=0.031 and p=0.006). Western blotting analysis showed that AQP-1 and AQP-5 protein levels at 12h were significantly higher in BMSC-SAP rats than in control-SAP rats (p<0.001). CONCLUSIONS: Allogenic BMSC transplantation can protect against ALI in a rat SAP model and can also regulate the expression levels of AQP-1 and -5 by inhibiting IL-1ß and TNF-a.

17ß-Estradiol administration attenuates seawater aspiration-induced acute lung injury in rats.

There is very little evidence on the value of administering estrogen in cases of seawater drowning which can induce acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Therefore, this study aimed to investigate whether 17ß-estradiol (E2) treatment can attenuate seawater aspiration-induced ALI in rats. In the experiment, ALI was induced by endotracheal instillation of seawater (4mL/kg) and the rats were then given intraperitoneal injection of E2 (5mg/kg) 20min after seawater instillation. Finally, the changes of arterial blood gases which contained hydrogen ion concentration (pH), arterial oxygen tension (PaO(2)) and arterial carbon dioxide tension (PaCO(2)) were measured and the measurement of extravascular lung water (EVLW) was observed. The pulmonary histological changes were evaluated by hematoxylin-eosin stain. The expression of aquaporins (AQPs) 1, AQP5, and estrogen receptor-ß (ERß) was measured by western blotting and immunohistochemical methods. The results showed that compared with normal saline water, seawater aspiration induced more serious ALI in rats which was markedly alleviated by E2 treatment. Meanwhile, the ERß in lung tissues was activated after E2 administration. The seawater aspiration group also presented with severe pulmonary edema which was paralleled with over expressed AQP1 and AQP5. However, the up-regulation of AQP1 and AQP5 was suppressed by the administration of E2, resulting in an attenuation of lung edema. In conclusion, E2 treatment could effectively attenuate seawater aspiration-induced acute lung injury in rats by the down-regulation of AQP1 and AQP5.

The protective role of aquaporins in the freeze-tolerant insect Eurosta solidaginis: functional characterization and tissue abundance of EsAQP1.

The movement of water and small solutes is integral to the survival of freezing and desiccation in insects, yet the underlying mechanisms of these processes are not fully known. Recent evidence suggests that aquaporin (AQP) water channels play critical roles in protecting cells from osmotic damage during freezing and desiccation. Our study sequenced, functionally characterized and measured the tissue abundance of an AQP from freeze-tolerant larvae of the gall fly, Eurosta solidaginis (Diptera: Tephritidae). The newly characterized EsAQP1 contains two NPA motifs and six transmembrane regions, and is phylogenetically related to an AQP from the anhydrobiotic chironomid Polypedilum vanderplanki. Using a Xenopus laevis oocyte swelling assay, we demonstrated that EsAQP1 increases water permeability to nine times that of simple diffusion through the membrane. In contrast to its high water permeability, EsAQP1 was impermeable to both glycerol and urea. The abundance of EsAQP1 increased from October to December in all tissues tested and was most abundant in the brain of winter larvae. Because the nervous system is thought to be the primary site of freezing injury, EsAQP1 may cryoprotect the brain from damage associated with water imbalance. The sequence, phylogenetic relationship, osmotic permeability, tissue distribution and seasonal abundance of EsAQP1 further support the role of AQPs in promoting freezing tolerance.

Effect of irradiation on microvascular endothelial cells of parotid glands in the miniature pig.

PURPOSE: To evaluate the effect of irradiation on microvascular endothelial cells in miniature pig parotid glands. METHODS AND MATERIALS: A single 25-Gy dose of irradiation (IR) was delivered to parotid glands of 6 miniature pigs. Three other animals served as non-IR controls. Local blood flow rate in glands was measured pre- and post-IR with an ultrasonic Doppler analyzer. Samples of parotid gland tissue were taken at 4 h, 24 h, 1 week, and 2 weeks after IR for microvascular density (MVD) analysis and sphingomyelinase (SMase) assay. Histopathology and immunohistochemical staining (anti-CD31 and anti-AQP1) were used to assess morphological changes. MVD was determined by calculating the number of CD31- or AQP1-stained cells per field. A terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) apoptosis assay was used to detect apoptotic cells. The activity of acid and neutral Mg(2+)-dependent SMase (ASMase and NSMase, respectively) was also assayed. RESULTS: Local parotid gland blood flow rate decreased rapidly at 4 h post-IR and remained below control levels throughout the 14-day observation period. Parotid MVD also declined from 4 to 24 hours and remained below control levels thereafter. The activity levels of ASMase and NSMase in parotid glands increased rapidly from 4 to 24 h post-IR and then declined gradually. The frequency of detecting apoptotic nuclei in the glands followed similar kinetics. CONCLUSIONS: Single-dose IR led to a significant reduction of MVD and local blood flow rate, indicating marked damage to microvascular endothelial cells in miniature pig parotid glands. The significant and rapid increases of ASMase and NSMase activity levels may be important in this IR-induced damage.