OBJECTIVETo evaluate the effect of water channel aquaporin 4 (AQP4) on bleomycin-induced lung fibrosis in mice.

METHODSIn wild type and AQP4 gene knockout (AQP4-/-) mice, lung fibrosis was induced by injection of bleomycin (3 mg/kg) into the trachea and saline injection was used as a control. At d3, 7, 14, 28 after bleomycin-treatment, mice were randomly sacrificed in batch and the lung coefficient was determined. Serum levels of TGF-β1 and TNF-α were measured by ELISA and hydroxyproline contents in lung tissue were determined by Alkaline hydrolysis method. H-E staining and Masson's staining were performed to examine the pathological changes of lung tissues after bleomycin-treatment.

RESULTSOn d14 after bleomycin-treatment, the lung coefficients in wild type mice and AQP4-/- mice were 1.9-fold (12.69 ± 6.05 vs 6.80 ± 0.82, q=4.204, P<0.05) and 2.3-fold (14.05 ± 5.82 vs 6.05± 0.58, q=5.172, P<0.01) of that in control, respectively, but no significant difference was found between wild type and AQP4-/- mice in the lung coefficient value (P>0.05). The hydroxyproline contents in the lung increased after bleomycin-treatment; on d28, the lung hydroxyproline contents in wild type and in AQP4-/- mice were 1.55-fold (0.85 ± 0.22 g/mg vs 0.55 ± 0.14 μg/mg, q=4.313, P<0.05) and 1.4-fold (0.84 ± 0.13 μg/mg vs 0.60 ± 0.14μg/mg, q=4.595，P<0.05) of that in control, respectively, but no significant difference was noticed between wild type and AQP4-/- mice in lung hydroxyproline contents. There was a tendency that serum TGF-β1 and TNF-α levels increased in bleomycin-treated mice, but no significant difference was found between wild type and AQP4-/- mice. AQP4-knockout showed no effects on pathological changes of lung tissues with H-E staining and Masson's staining in mice with bleomycin-induced lung fibrosis.

CONCLUSIONAQP4 might not be involved in bleomycin-induced lung fibrosis in mice.

Animals ; Aquaporin 4 ; genetics ; Bleomycin ; toxicity ; Male ; Mice ; Mice, Knockout ; Pulmonary Fibrosis ; chemically induced ; genetics

OBJECTIVETo investigate the expression of aquaporin 4 (AQP4) after microwave exposure and the correlation with the brain injury by radiation.

METHODS70 male rats were exposed to microwave whose average power density was 0, 10, 30 and 100 mW/cm(2) respectively. Rats were sacrificed at 6 h, 1 d, 3 d and 7 d after exposure. Immunohistochemistry and Western blot were used to detect the expression of AQP4 in protein level in rat hippocampus, and the expression of AQP4 in gene level was measured by in situ hybridization and RT-PCR.

RESULTSThe expression of AQP4 in rat hippocampus was abnormal after 10, 30, 100 mW/cm(2) microwave exposure. The protein level showed increased at first and then recovered at 10 and 30 mW/cm(2) groups, while increased progressively in 100 mW/cm(2) group within 14 d (P < 0.01). The gene expression of AQP4 was increased (0.51 +/- 0.02) at the beginning (6 h) and then regained after 10 mW/cm(2) microwave exposure, while in 30 and 100 mW/cm(2) groups, it rose to the peak at 7 d (0.46 +/- 0.02 and 0.43 +/- 0.08) and didn't get back (P = 0.004; P = 0.012).

CONCLUSIONMicrowave radiation can increase the expression of AQP4 in rat hippocampus. The change might participate in the process of increasing permeability of blood-brain barrier and lead to the brain edema after microwave radiation.

Animals ; Aquaporin 4 ; genetics ; metabolism ; Hippocampus ; metabolism ; radiation effects ; Male ; Microwaves ; adverse effects ; Rats ; Rats, Wistar

OBJECTIVETo evaluate the role of water channel AQP4 in NMDA-induced brain injury in mice.

METHODSIn AQP4 gene knockout (AQP4(-/-)) mice, brain injury was induced by microinjection of NMDA into the cortex. The injured area was determined by toluidine blue staining, degenerated neurons were detected by Fluro-Jade B staining, and increased blood-brain barrier (BBB) permeability was evaluated by IgG immunostaining.

RESULTCompared with wild-type mice, AQP4(-/-) mice exhibited increased cortical lesion area, aggravated neuron degeneration, and increased BBB disruption after NMDA microinjection.

CONCLUSIONAQP4 may play a protective role in NMDA-induced brain injury in mice.

Animals ; Aquaporin 4 ; genetics ; physiology ; Blood-Brain Barrier ; pathology ; Brain ; drug effects ; pathology ; Mice ; Mice, Knockout ; N-Methylaspartate ; toxicity

OBJECTIVETo explore the changes of vascular endothelial growth factor(VEGF), aquaporin (AQP) gene and protein expression during hypoxic encephaledema so as to provide the basis for elucidating the brain injury caused by acute hypoxic exposure and pathogenesis of the encephaledema.

METHODSWistar rats were randomly divided into 4 groups, i.e. control group, hypoxia 4 000 m group, hypoxia 6 000 m group and hypoxia 8 000 m group. Rats in hypoxic groups were exposed to hypoxia at simulated altitude of 4 000 m, 6 000 m and 8 000 m above sea level for 8 hours respectively in order to establish hypoxic encephaledema model. The water content in brain was determined by dry-weight method. The changes in morphology of brains were observed under optical microscope. The changes in expression of VEGF, AQP1 and AQP4 genes and protein were determined by RT-PCR and immunohistochemistry.

RESULTS(1) The results determined by dry-weight method indicated that water content of rats brain increased markedly after rats were exposed to a simulated altitude at 6 000 m, 8 000 m. (2) The results determined by microscopy indicated that during the rats exposed to hypoxia, nerve cells, vascular endothelial cells and astrocyte foot processes swelled lightly, transudate occurred in tissues at 4 000 m. The swelling of vascular endothelial cell (VEC) and astrocyte foot processes aggravated, interspace between vessels and tissues enlarged, and transudate in tissue increased at 6 000 m. The swelling of VEC and astrocyte foot processes went from bad to worse, interspace between vessels and tissues enlarged further, and transudate in tissue increased evidently at 8 000 m. (3) During hypoxic encephaledema, the expression of VEGF, AQP1 and AQP4 mRNA increased, AQP1 was abnormally expressed on the surface of VEC, and the expressive level of VEGF and AQP1 on VEC and AQP4 on astrocyte foot processes increased.

CONCLUSIONThe changes in expression and distribution of VEGF, AQP1 and AQP4 during encephaledema caused by hypoxic exposure may induce blood-brain barrier injury, and may be one of the pathogenesis of hypoxic encephaledema.

Animals ; Aquaporin 1 ; genetics ; metabolism ; Aquaporin 4 ; genetics ; metabolism ; Blood-Brain Barrier ; pathology ; Brain ; metabolism ; Brain Edema ; etiology ; metabolism ; physiopathology ; Hypoxia ; complications ; metabolism ; Male ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Vascular Endothelial Growth Factor A ; genetics ; metabolism

OBJECTIVETo explore the relationship between aquaporin 3,4 (AQP3, AQP4) gene expression in gastric mucosa and severity of Pi-Wei damp-heat syndrome (PWDHS) in patients with chronic superficial gastritis (CSG).

METHODSGastric mucosa taken from the upper part of gastric corpus was collected under gastroscope and preserved in liquid nitrogen. The gene expression of AQP3 and AQP4 was determined quantitatively by fluorescent PCR.

RESULTSThe gene expression of AQP3 and AQP4 in patients with PWDHS of moderate and severe degree was higher than that in those of mild degree and in healthy persons respectively (P <0.05 and P <0.01); and the gene expression of AQP3 in patients with PWDHS of severe degree was higher than that in those of moderate degree (P<0.05).

CONCLUSIONThe gene expression of AQP3 and AQP4 in gastric mucosa was correlative with the severity of PWDHS in patients with chronic superficial gastritis, the severer the syndrome, the higher the gene expression.

Adult ; Aquaporin 3 ; genetics ; Aquaporin 4 ; genetics ; Chronic Disease ; Diagnosis, Differential ; Female ; Gastric Mucosa ; metabolism ; pathology ; Gastritis ; diagnosis ; genetics ; Gene Expression ; Humans ; Male ; Medicine, Chinese Traditional ; Middle Aged ; Reverse Transcriptase Polymerase Chain Reaction ; methods ; Syndrome

The aim of this study was to investigate the effects of Avastin on aquaporin4 (AQP4) expression in human retinal Müller cells in vitro under hypoxia, so as to explore the mechanism of Avastin treating retinal edema. The human Müller cells were cultured using the enzymatic digestion method. Müller cells were identified under the transmission electron microscopy and by using immunofluorescence staining. By using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), the expression of AQP4 mRNA and VEGF mRNA in Müller cells cultured with 500 μmol/L CoCl(2) for 0, 3, 6, 12 and 24 h, and with 0, 100, 300, 500 and 700 μmol/L CoCl(2) for 24 h was detected. The expression of AQP4 mRNA in Müller cells cultured with 50 ng/mL exogenous vascular endothelial growth factor (VEGF) for 0, 0.5, 1, 2 and 4 h, and with 0, 25, 50 and 75 ng/mL VEGF for 24 h was detected. Amplified cDNA products of AQP4 mRNA in Müller cells cultured with 500 μmol/L CoCl(2) and 200 μg/mL Avastin for 24 h were detected. The results showed that more than 95% cells displayed positive immunofluorescence reaction. Characteristic 8-10 nm intracellular filaments could be seen in the cytoplasm under the transmission electron microscopy. In the CoCl(2) experimental groups, the expression of AQP4 mRNA and VEGF mRNA in Müller cells was increased as compared with the control group. Alteration of AQP4 mRNA and VEGF mRNA levels showed a significantly positive correlation (r (2)=0.822, P<0.05). The expression of AQP4 mRNA in Müller cells was increased by VEGF. The expression of AQP4 mRNA was significantly decreased by Avastin as compared with the control group. It is suggested that Avastin can decrease the expression of AQP4 mRNA in human Müller cells under chemical hypoxic conditions partially via VEGF path, which may be one of the mechanisms of Avastin treating retinal edema.
Antibodies, Monoclonal, Humanized ; pharmacology ; Aquaporin 4 ; genetics ; metabolism ; Bevacizumab ; Cells, Cultured ; Ependymoglial Cells ; metabolism ; Gene Expression ; drug effects ; genetics ; Humans ; Hypoxia ; genetics ; metabolism

OBJECTIVETo explore the relationship between Pi-Wei Damp-Heat Syndrome (PWDHS) with expression of aquaporin (AQP) 3,4 gene in gastric mucosa and the effects of Qingre Huashi Recipe (QHR) on the expression.

METHODSSixty-eight patients with chronic superficial gastritis were differentiated into Pi-Wei Damp-Heat Syndrome group (PWDHS, n = 53, 19 cases with predominant Dampness, 14 cases with predominant Heat, 20 cases with Dampness equal to Heat) and Pi deficiency Syndrome group (PDS, n = 15). The PWDHS were treated with QHR. The expression of AQP 3,4 gene in the two groups were determined by fluorescence quantitative polymerase chain reaction (FQ-PCR).

RESULTSExpression of AQP 3 gene in PWDHS was higher than that in PDS and the healthy group, but the difference showed no statistical significance. Expression of AQP 4 gene in PWDHS was obvious higher than that in PDS and the healthy group (P <0.05 or P <0.01), but the difference of AQP 4 gene expression between PDS and the healthy group was insignificant. Comparison among various sub-types of PWDHS showed that the AQP 4 gene expression in the predominant dampness > dampness equal to heat> predominant heat. AQP 3,4 gene expression in PWDHS was significantly decreased after QHR treatment, especially in the cases with predominant dampness syndrome (P <0.01), approaching that in the healthy group and PDS.

CONCLUSIONAbnormal expression of AQP 3,4 gene may be one of the possible mechanisms of PWDHS pathogenesis, Chinese herbs could influence AQP 3,4 gene expression to play a key role in treatment.

Adult ; Aquaporin 3 ; Aquaporin 4 ; Aquaporins ; biosynthesis ; genetics ; Diagnosis, Differential ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Gastric Mucosa ; metabolism ; Gastritis ; drug therapy ; genetics ; metabolism ; Humans ; Male ; Medicine, Chinese Traditional ; Phytotherapy

OBJECTIVETo investigate the effect of rhubarb on expressions of aquaporin-2 and 4 (AQP2 and AQP4) in rat's kidney.

METHODSThirty-two SD rats were randomly divided into 4 groups, the normal control group, and the three rhubarb groups medicated via gastrogavage with low, mid and high dose of rhubarb extract (total anthraquinone) respectively. The 6 h and 24 h urine volume were measured, and the protein and mRNA expressions of AQP2 and AQP4 in renal tissue were determined with immunohistochemistry, Western blot and RT-PCR.

RESULTSNo significant difference between the control group and the low dose rhubarb treated group was found in urine volume, as well as in AQP2 and AQP4 protein and mRNA expressions. But the urine volume was obviously higher, the protein and mRNA expressions of AQP2 and AQP4 were markedly lower in rats after mid/high dose rhubarb medication respectively when compared with those in the normal controls (all P < 0.01).

CONCLUSIONRhubarb can inhibit the protein and mRNA expressions of AQP2 and AQP4 in rats' kidney, which probably is one of the mechanisms of rhubarb for diuresis.

Animals ; Aquaporin 2 ; genetics ; metabolism ; Aquaporin 4 ; genetics ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; Gene Expression ; drug effects ; Kidney ; drug effects ; metabolism ; Male ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Rheum ; chemistry

OBJECTIVETo investigate the effects of aquaporin-4 (AQP4) gene knockout on the behavior changes and cerebral morphology during aging in mice,and to compare that of young and aged mice between AQP4 knockout mice (AQP4(-/-)) and wild type mice (AQP4(+/+)).

METHODSFifty-eight CD-1 mice were divided into four groups: young (2-3 months old) AQP4(-/-), aged (17-19 months old) AQP4(-/-), young AQP4(+/+) and aged AQP4(+/+). The activity levels and exploring behavior of mice were tested in open field. The neurons were stained with toluidine blue and NeuN, the astrocytes and microglia were stained with GFAP and Iba-1, respectively. The morphological changes of neuron, astrocyte and microglia were then analyzed.

RESULTSCompared with young mice, the total walking distance in open field of aged AQP4(+/+) mice and aged AQP4(-/-) mice decreased 41.2% and 44.1%, respectively (P<0.05); while there was no difference in the ratio of distance and retention time in the central area of open field. The density of neuron in cortex of aged AQP4(+/+) mice and aged AQP4(-/-) mice decreased 19.6% and 15.8%, respectively (P<0.05), while there was no difference in the thickness of neuron cell body in hippocampus CA1 region. The density of astrocyte in hippocampus CA3 region of aged AQP4(+/+) mice and aged AQP4(-/-) mice increased 57.7% and 64.3%, respectively (P<0.001), while there was no difference in the area of astrocyte. The area of microglia in hippocampus CA3 region of aged AQP4(+/+) mice and aged AQP4(-/-) mice increased 46.9% and 52.0%, respectively (P<0.01), while there was no difference in the density of microglia. Compared with AQP4(+/+) mice, the young and aged AQP4(-/-) mice showed smaller area of astrocyte in hippocampus CA3 region, reduced 18.0% in young mice and 23.6% in aged mice. There was no difference between AQP4(+/+) mice and AQP4(-/-) mice for other observed indexes.

CONCLUSIONAQP4 may be involved in change of astrocyte and astrocyte-related behaviors during aging. AQP4 gene knockout may have limited effects on the change of neuron, microglia and most neuronal behaviors in aging process.

Aging ; pathology ; Animals ; Aquaporin 4 ; genetics ; Astrocytes ; pathology ; Behavior, Animal ; Brain ; pathology ; Female ; Male ; Mice ; Mice, Knockout ; Microglia ; pathology ; Neurons ; pathology

OBJECTIVETo study the expression of aquaporin-4 (AQP4) protein in preeclampsia(PE) model rats.

METHODSAdult SD rats were divided into PE model group (n=7) induced by endotoxin, normal pregnancy group (n=6) and non-pregnancy group (n=12) treated with an equal volume of saline. AQP4 protein expression in the brain of the rats was detected with immunohistochemical staining and Western blotting.

RESULTSThe blood pressure in PE model rats (135∓9 mmHg) was significantly higher than that in normal pregnancy rats (116∓8 mmHg) and non-pregnancy rats (112∓6 mmHg) (P<0.02). The rats in PE model group showed obvious proteinuria compared with the other two groups (3.8∓0.5 vs 2.6∓0.6 and 2.3∓0.4, P<0.05). Immunohistochemistry showed that AQP4 protein was localized primarily around the brain parenchymal blood vessels. Western analysis revealed a significantly elevated AQP4 protein expression in PE model group (39.6∓4.9) compared with that in normal pregnancy group (26.5∓4.3) and non-pregnancy group (9.7∓2.1) (P<0.01).

CONCLUSIONThe up-regulation of AQP4 protein around the intraparenchymal blood vessels of the brain may play a role in the development of eclampsia.

Animals ; Aquaporin 4 ; genetics ; metabolism ; Blood Pressure ; Disease Models, Animal ; Female ; Hippocampus ; metabolism ; Pre-Eclampsia ; metabolism ; Pregnancy ; Rats ; Rats, Sprague-Dawley