This study aims to explore the role and mechanism of berberine in promoting the expression of aquaporin 4(AQP4) in astrocytes by regulating the expression of miR-383-5p in HepG2 cell-derived exosomes under insulin resistance(IR). The IR-HepG2 cell model was established with 1×10~(-6) mol·L~(-1) insulin. With metformin as the positive control, the safe concentrations of berberine and metformin were screened by cell counting kit-8(CCK-8) and lactate dehydrogenase(LDH) leakage assays, and the effect of berberine on the IR of HepG2 cells was evaluated by glucose consumption. NanoSight was used to measure the particle size and concentration of exosomes secreted by HepG2 cells in each group. HepG2 cell-derived exosomes in each group were incubated with astrocytes for 24 h, and the protein and mRNA levels of AQP4 in HA1800 cells were determined by Western blot and qRT-PCR, respectively. qRT-PCR was performed to determine the expression of miR-383-5p in HepG2 cell-derived exosomes and HA1800 cells after co-incubation. Western blotting was employed to determine the expression levels of miRNAs and proteins associated with exosome production and release in HepG2 cells. The results showed that 10 μmol·L~(-1) berberine and 1 mmol·L~(-1) metformin significantly alleviated the IR of HepG2 cells and reduced the concentration of exosomes in HepG2 cells. The exosomes of HepG2 cells treated with berberine and metformin significantly up-regulated the protein and mRNA levels of AQP4 in HA1800 cells. The mRNA level of miR-383-5p in HepG2 cell exosomes and HA1800 cells co-incubated with berberine and metformin decreased significantly. The intervention with berberine and metformin significantly down-regulated the expression of proteins associated with the production of miRNAs(Dicer, Drosha) as well as the production(Alix, Vps4A) and release(Rab35, VAMP3) of exosomes in IR-HepG2 cells. In conclusion, berberine can promote the expression of AQP4 in astrocytes by inhibiting the production and release of miR-383-5p in HepG2-derived exosomes under IR.
Humans ; MicroRNAs/metabolism* ; Berberine/pharmacology* ; Hep G2 Cells ; Exosomes/genetics* ; Aquaporin 4/metabolism* ; Insulin Resistance ; Astrocytes/drug effects*

This study investigated the therapeutic effects and mechanisms of Modified Yiyi Fuzi Baijiang Powder on ulcerative colitis(UC) in rats from the perspective of dampness. SD rats were randomly allocated into six groups(n=10): control, model, mesalazine, and Modified Yiyi Fuzi Baijiang Powder at low(3.96 g·kg~(-1)·d~(-1)), medium(7.92 g·kg~(-1)·d~(-1)), and high(15.84 g·kg~(-1)·d~(-1)) doses. UC was induced in all groups except the control by administration with 3% dextran sulfate sodium(DSS) solution for 7 days. The disease activity index(DAI) was recorded, and the colon tissue was collected for analysis. Histopathological changes were assessed by hematoxylin-eosin staining. Serum levels of D-lactic acid(D-LA) and diamine oxidase(DAO) were measured by ELISA. Immunohistochemistry and PCR were employed to evaluate the expression of aquaporins(AQP3, AQP4) and tight junction proteins [zonula occludens-1(ZO-1) and occludin] at both protein and mRNA levels. Compared with the control group, the model group showed an increased DAI scores(P<0.05), intestinal mucosal damage, elevated serum levels of DAO and D-LA(P<0.05), and decreased expression of AQP3, AQP4, ZO-1, and occludin(P<0.05). Treatment with Modified Yiyi Fuzi Baijiang Powder reduced the DAI scores(P<0.05), lowered the serum levels of D-LA and DAO(P<0.05), and upregulated the expression of AQP3, AQP4, ZO-1, and occludin at both protein and mRNA levels compared with the model group. These findings suggest that Modified Yiyi Fuzi Baijiang Powder exerts therapeutic effects on UC by reducing the intestinal mucosal permeability, promoting colonic mucosal repair, and regulating abnormal intestinal water metabolism, which may involve the upregulation of AQP3 and AQP4 expression.
Animals ; Colitis, Ulcerative/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Rats, Sprague-Dawley ; Rats ; Intestinal Mucosa/metabolism* ; Male ; Aquaporin 3/metabolism* ; Aquaporin 4/metabolism* ; Permeability/drug effects* ; Humans ; Powders ; Intestinal Barrier Function

OBJECTIVE: To investigate the effect of aquaporin 5 (AQP5) on Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor κB (NF-κB) signaling pathway in Sjögren syndrome (SS) rats. METHODS: The SS gene expression data sets GSE406611 and GSE84844 were extracted from the Gene Expression Omnibus (GEO), and the AQP5 mRNA expression was analyzed by R software. The rat SS model was constructed. The successfully modeled rats were divided into SS group, SS+NC group, and SS+pc group, 10 rats in each group; and 10 rats were set as Normal group. The rats in the SS+NC group were injected with 10 μg of rno-pcDNA3.1-AQP5-NC at the submandibular gland, subcutaneously every day for 28 days. The rats in the SS+pc group were injected with 10 μg of rno-pcDNA3.1-AQP5 at the submandibular gland, subcutaneously every day for 28 days. The enzyme-linked immunosorbent assay (ELISA) kit was used to detect the content of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the serum. High-throughput sequencing was used to identify the target genes. Quantitative real-time PCR (qPCR) and Western blot were used to detect the mRNA and protein expressions of AQP5, TLR4, MyD88, and NF-κB in the rat submandibular gland tissue. RESULTS: In the SS dataset GSE406611 and GSE84844, the mRNA expression of AQP5 in SS was significantly reduced. Compared with the Normal group, the content of TNF-α and IL-1β in the serum, the mRNA and protein expressions of TLR4, MyD88, and NF-κB in the SS group were significantly increased, the mRNA and protein expressions of AQP5 were significantly decreased. After overexpression of AQP5, the content of TNF-α and IL-1β in the serum, the mRNA and protein expressions of TLR4, MyD88, and NF-κB in the SS+pc group were significantly decreased, the mRNA and protein expressions of AQP5 were significantly increased. The differences were statistically significant (all P < 0.05). CONCLUSION The expression of AQP5 is involved in the progression of SS. Increasing the expression of AQP5 can significantly inhibit inflammatory stress and reduce the pathological damage of submandibular gland tissue. This may be related to the inhibition of TLR4/MyD88/NF-κB conduction.
Animals ; Toll-Like Receptor 4/genetics* ; Myeloid Differentiation Factor 88/genetics* ; Aquaporin 5/metabolism* ; Sjogren's Syndrome/genetics* ; Signal Transduction ; NF-kappa B/metabolism* ; Rats ; Rats, Sprague-Dawley ; Interleukin-1beta/metabolism* ; Female

This study aims to explore the pharmacodynamic effect of baicalin on rat brain edema induced by cerebral ischemia reperfusion injury and discuss the mechanism from the perspective of inhibiting astrocyte swelling, which is expected to serve as a refe-rence for the treatment of cerebral ischemia with Chinese medicine. To be specific, middle cerebral artery occlusion(suture method) was used to induce cerebral ischemia in rats. Rats were randomized into normal group, model group, high-dose baicalin(20 mg·kg~(-1)) group, and low-dose baicalin(10 mg·kg~(-1)) group. The neurobehavior, brain index, brain water content, and cerebral infarction area of rats were measured 6 h and 24 h after cerebral ischemia. Brain slices were stained with hematoxylin and eosin(HE) for the observation of pathological morphology of cerebral cortex after baicalin treatment. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the content of total L-glutathione(GSH) and glutamic acid(Glu) in brain tissue, Western blot to measure the content of glial fibrillary acidic protein(GFAP), aquaporin-4(AQP4), and transient receptor potential vanilloid type 4(TRPV4), and immunohistochemical staining to observe the expression of GFAP. The low-dose baicalin was used for exploring the mechanism. The experimental results showed that the neurobehavioral scores(6 h and 24 h of cerebral ischemia), brain water content, and cerebral infarction area of the model group were increased, and both high-dose and low-dose baicalin can lower the above three indexes. The content of GSH dropped but the content of Glu raised in brain tissue of rats in the model group. Low-dose baicalin can elevate the content of GSH and lower the content of Glu. According to the immunohistochemical staining result, the model group demonstrated the increase in GFAP expression, and swelling and proliferation of astrocytes, and the low-dose baicalin can significantly improve this situation. The results of Western blot showed that the expression of GFAP, TRPV4, and AQP4 in the cerebral cortex of the model group increased, and the low-dose baicalin reduce their expression. The cerebral cortex of rats in the model group was severely damaged, and the low-dose baicalin can significantly alleviate the damage. The above results indicate that baicalin can effectively relieve the brain edema caused by cerebral ischemia reperfusion injury in rats, possibly by suppressing astrocyte swelling and TRPV4 and AQP4.
Animals ; Aquaporin 4/genetics* ; Astrocytes ; Brain Edema/drug therapy* ; Brain Ischemia/metabolism* ; Flavonoids ; Infarction, Middle Cerebral Artery/drug therapy* ; Rats ; Rats, Sprague-Dawley ; Reperfusion ; TRPV Cation Channels/therapeutic use*

OBJECTIVE: To observe the characteristics of the interstitial fluid (ISF) drainage in the Alzheimer's disease (AD) rats through magnetic resonance imaging (MRI) tracer gadolinium-diethylene triamine pentacetic acid (Gd-DTPA)spread in the brain extracellular space (ECS) and to discuss the role of aquaporin-4 (Aqp4) in the AD. METHODS: Wild type SD rats (300-350 g) and Aqp4 gene knock out (Aqp4^-/-) SD rats (300-350g) were divided into Sham group, AD group, Aqp4^-/--Sham group and Aqp4^-/--AD group. Sham group and Aqp4^-/--Sham group were injected with saline by intraperitoneal each day for 6 weeks, and the AD group and Aqp4^-/--AD group were injected with D-galactose by intraperitoneal each day for 6 weeks. MRI tracer Gd-DTPA (10 mmol/L, 2 μL) was injected into the hippocampus of the rats. MRI scan was performed at the end of 0.5 h, 1.5 h, 1 h, 2 h, and 3 h to observe the dynamic distribution of the Gd-DTPA in the hippocampus and the diffusion rate D^*, clearance rate k' and half-life t_1/2 measured. RESULTS: The diffusion rate D* in Sham group was (2.66±0.36)×10^-6 mm2/s, the diffusion rate D^* in AD group was (2.72±0.62)×10-6 mm²/s, the diffusion rate D^* in Aqp4^-/--Sham group was (2.75±0.47)×10^-6 mm²/s, the diffusion rate D^* in Aqp4^-/--AD group was (2.802±0.55)×10^-6 mm²/s, and there was no statistically significant difference in the four groups (One-Way ANOVA, P>0.05).The clearance rate k' in Sham group was (4.57±0.14)×10^-4/s, the clearance rate k' in AD group was (3.68±0.22)×10^-4/s, the clearance rate k' in Aqp4^-/--Sham group was (3.17±0.16)×10^-4/s, the clearance rate k' in Aqp4^-/--AD group was (2.59±0.19)×10^-4/s, and there was significant difference in the four groups (One-Way ANOVA, P<0.05). The half-life t_1/2 in Sham group was (0.67±0.12) h, the half-life t_1/2 in AD group was (0.88±0.08) h, the half-life t_1/2 in Aqp4^-/--Sham group was (1.12±0.15) h, the half-life t_1/2 in Aqp4^-/--AD group was (1.58±0.11) h, and there was significance difference in the four groups(one-way ANOVA,P<0.05). CONCLUSION The ISF drainage is slow after AD and the loss of Aqp4 in the AD makes the ISF drainage obviously slow down, Aqp4 plays an important role in AD to remove the metabolism of waste out of the brain.
Alzheimer Disease/physiopathology* ; Animals ; Aquaporin 4/genetics* ; Brain/physiopathology* ; Diffusion ; Drainage ; Extracellular Fluid ; Extracellular Space ; Gadolinium DTPA ; Magnetic Resonance Imaging ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To observe the expression of aquaporin 4 (AQP4) in diffuse brain injury (DBI) of rats and to explore the corresponding effect of AQP4 for brain edema. METHODS: The rat model of DBI was established using Marmarou's impact-compression trauma model. Brain water content was measured by dry-wet weight method. Blood-brain barrier permeability was evaluated by Evans blue (EB) staining. Immunohistochemical method was used to observe the expression of AQP4. RESULTS: Brain water content increased after 3 h and peaked at 24 h after DBI. Brain EB content significantly increased and peaked at 12 h after DBI. The expression of AQP4 significantly increased after 3 h and peaked at 24 h after DBI, and the number of AQP4 positive astrocytes increased. CONCLUSION The increment of the permeability of blood-brain barrier and the expression of AQP4 may contribute to the development of brain edema in rat DBI. The change of AQP4 expression in astrocytes may also contribute to determine DBI.
Animals ; Aquaporin 4/metabolism* ; Astrocytes ; Blood-Brain Barrier/metabolism* ; Brain ; Brain Edema/metabolism* ; Brain Injuries/metabolism* ; Cell Membrane Permeability/genetics* ; Disease Models, Animal ; Permeability ; Rats ; Water

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 observe the effect of Xingnaojing Injection combined with minimally invasive percutaneous drainage on brain edema and content of serum aquaporin-4 (AQP4) in patients with moderate hypertensive basal ganglia hemorrhage, and discuss the treatment mechanism of Xingnaojing injection combined with minimally invasive percutaneous drainage for cerebral hemorrhage.

METHODForty-two patients with moderate (25-50 mL) hypertensive basal ganglia hemorrhage (< 24 h) were selected and randomly divided into two groups: the observation group (n = 22) and the control group (n = 20). The neurological severity score were evaluated by the NIHSS (national institutes of health stroke scale), the volume of brain edemas were measured by head CT, the serum levels of AQP4 were determined by ELISA method on admission and 1 and 2 weeks after treatment.

RESULTOn admission, there was no significant difference in the scores of NIHSS, the volume of brain edemas and the level of serum AQP4 between the observation group and the control group. At the end of the first week after the treatment, the score of NIHSS of the observation group were lower than that of the control group, with significant different (P < 0.05); the observation group showed reduced volume of brain edemas than that on admission (P < 0.05), whereas the control group the control group showed increased volume of brain edemas than that on admission; the control group displayed increased level of serum AQP4 than that on admission, but without significant difference; the observation group displayed decreased level of serum AQP4 than that on admission (P < 0.05). At the end of the second week after the treatment, the control group showed decreased score of NIHSS than that on admission and at the end of the first week after treatment (P < 0.05). Compared with the control group, the observation group showed a much lower score of NIHSS (P < 0.01), the control group displayed reduced volume of brain edemas than that on admission and at the end of the first week after treatment, but the observation group was even lower than the control group. Both of observation and control groups displayed significantly reduced level of AQP4 (P < 0.05), but the observation group showed a lower AQP4 level than that of the control group (P < 0.05).

CONCLUSIONThe therapy of Xingnaojing injection combined with minimally invasive percutaneous drainage could remarkably reduce brain edema, and promote neural functional recovery, thus could be selected as a therapeutic regimen for patients with moderate hypertensive basal ganglia hemorrhage.

Aged ; Aquaporin 4 ; blood ; genetics ; Basal Ganglia Hemorrhage ; blood ; drug therapy ; etiology ; surgery ; Brain Edema ; blood ; drug therapy ; etiology ; surgery ; Drainage ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Humans ; Hypertension ; complications ; Male ; Middle Aged ; Treatment Outcome

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

The deficiency of aquaporin-4 (AQP4) has been reported to alter release of neurotransmitters in the mouse brain. However, the functional relevance of AQP4 in mediating essential components of the general anaesthetic state is unknown. The aim of the present study was to investigate the role of AQP4 in general anaesthesia in mice lacking AQP4. The hypnotic effects of propofol, ketamine, and pentobarbital in AQP4 knockout (KO) and CD1 control mice were evaluated using the behavioural endpoint of loss of righting reflex (LORR). The effects of propofol on extracellular levels of amino acids in prefrontal cortex of freely moving mice were investigated using microdialysis coupled to high performance liquid chromatography with fluorescent detection. The result showed that, after receiving ketamine or pentobarbital, LORR occurred at earlier time in KO mice than that in control animals. Intraperitoneal injection of ketamine or pentobarbital increased the duration of LORR. After the administration of propofol, the duration of LORR was significantly reduced in KO mice compared with that in controls. Propofol increased the extracellular levels of aspartate, glutamate, and GABA, but not taurine, in prefrontal cortex. There were significant differences of increase patterns of the three kinds of neurotransmitters between KO and WT mice. Notably, the duration of GABA level increase correlated with the duration of LORR in two genotypes of mice. These results provide in vivo evidence of different responses in time-dependent release of excitatory and inhibitory neurotransmitters in prefrontal cortex of the two genotypes of mice. It is suggested that changes in anaesthetic reactions in mice with AQP4 loss may be related to neurotransmitter regulation, and that normal functioning of AQP4 plays an important role in the maintenance of anaesthetic hypnosis.
Anesthetics, Intravenous ; pharmacology ; Animals ; Aquaporin 4 ; deficiency ; genetics ; Hypnotics and Sedatives ; pharmacology ; Ketamine ; pharmacology ; Mice ; Mice, Knockout ; Neurotransmitter Agents ; metabolism ; Pentobarbital ; pharmacology ; Prefrontal Cortex ; drug effects ; metabolism ; Propofol ; pharmacology