The Expression and Role of Aquaporin 4 in Colon Cancer.

BACKGROUND/AIM: Aquaporins (AQPs) were initially discovered as water channel proteins that facilitate transcellular water movements. Recent studies have shown that AQPs are expressed and play an oncogenic role in various cancers. However, the expression and role of Aquaporin 4 (AQP4) in colon cancer have not been investigated. This study aimed to examine the clinical and pathophysiologic significance of AQP4 in colon cancer. PATIENTS AND METHODS: Immunohistochemistry (IHC) of AQP4 for 145 primary tumor samples obtained from patients with stage II or III colon cancer was performed, and the relationship between AQP4 expression and patients' prognoses was analyzed. Knockdown experiments with AQP4 small interfering RNA using human colon cancer cells were conducted to analyze the effects on cell invasiveness. RESULTS: IHC revealed that AQP4 was scarcely expressed in the noncancerous colonic mucosa. Of the 145 patients who enrolled in this study, 109 (75.2%) and 36 (24.8%) patients were classified as negative and positive for AQP4 expression, respectively. A high level of AQP4 expression is significantly associated with deeper tumors with lymph node metastasis and venous invasion. A 5-year progression-free survival rate of AQP4-positive patients was significantly worse than that of AQP-4 negative patients (70.7% vs. 87.0%, p=0.049). Furthermore, AQP4 knockdown significantly inhibited cell migration and invasion in HCT116 cells. CONCLUSION: AQP4 may be a novel biomarker and therapeutic target for colon cancer.

A novel interaction between aquaporin 1 and caspase-3 in pulmonary arterial smooth muscle cells.

Pulmonary hypertension (PH) is a condition in which remodeling of the pulmonary vasculature leads to hypertrophy of the muscular vascular wall and extension of muscle into nonmuscular arteries. These pathological changes are predominantly due to the abnormal proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs), enhanced cellular functions that have been linked to increases in the cell membrane protein aquaporin 1 (AQP1). However, the mechanisms underlying the increased AQP1 abundance have not been fully elucidated. Here we present data that establishes a novel interaction between AQP1 and the proteolytic enzyme caspase-3. In silico analysis of the AQP1 protein reveals two caspase-3 cleavage sites on its C-terminal tail, proximal to known ubiquitin sites. Using biotin proximity ligase techniques, we establish that AQP1 and caspase-3 interact in both human embryonic kidney (HEK) 293A cells and rat PASMCs. Furthermore, we demonstrate that AQP1 levels increase and decrease with enhanced caspase-3 activity and inhibition, respectively. Ultimately, further work characterizing this interaction could provide the foundation for novel PH therapeutics.NEW & NOTEWORTHY Pulmonary arterial smooth muscle cells (PASMCs) are integral to pulmonary vascular remodeling, a characteristic of pulmonary arterial hypertension (PAH). PASMCs isolated from robust animal models of disease demonstrate enhanced proliferation and migration, pathological functions associated with increased abundance of the membrane protein aquaporin 1 (AQP1). We present evidence of a novel interaction between the proteolytic enzyme caspase-3 and AQP1, which may control AQP1 abundance. These data suggest a potential new target for novel PAH therapies.

Hypo-osmolality activates Wnt/ß-catenin mediated by AQP1 in nucleus pulposus cells degeneration.

The goals of this study were to investigate whether Wnt/ß-catenin signaling plays a role in hypo-osmolality-related degeneration of nucleus pulposus (NP) cells, and if so, to define the mechanism underlying AQP1 in this effect. Human NP cells were cultured under hypo-osmotic (300/350/400 mOsm) and iso-osmotic (450 mOsm) conditions. The cell viability, AQP1, the expression of Wnt/ß-catenin signaling, collagen II/I, and MMP3/9 were evaluated. To determine the effects of the Wnt/ß-catenin signaling, we used the inhibitor and the activator of Wnt during the hypo-osmotic culture of NP cells. We also examined whether the silencing and overexpressing of the AQP1 gene would affect the Wnt/ß-catenin expression in NP cells. Hypo-osmolality caused NP cell degeneration and activated the Wnt/ß-catenin signaling but suppressed the AQP1 level. Inhibiting the Wnt/ß-catenin signaling alleviated the hypo-osmolality-induced NP cell degeneration. On the contrary, activating Wnt/ß-catenin aggravated the NP cell degeneration under hypo-osmotic conditions, which did not affect AQP1 expression. AQP1-overexpressed NP cells exhibited decreased Wnt/ß-catenin signaling and alleviated cell degeneration under the hypo-osmotic condition. Besides, AQP1 silencing accelerated NP cell degeneration and activated Wnt/ß-catenin expression compared with untreated control. Hypo-osmolality promotes NP cell degeneration via activating Wnt/ß-catenin signaling, which is suppressed by AQP1 expression. The upregulation of AQP1 suppressed the Wnt/ß-catenin signaling and alleviated the hypo-osmolality induced by the NP cell degeneration.

Overexpression of aquaporin-1 plays a vital role in proliferation, apoptosis, and pyroptosis of Wilms' tumor cells.

BACKGROUND: Nephroblastoma, also known as Wilms' tumor (WT), is an embryonic malignant tumor and one of the most common malignant tumors in the abdominal region of children. The exact role and underlying mechanisms of aquaporin-1 (AQP1) in the occurrence and development of nephroblastoma remain unclear. METHODS: After overexpression of AQP1, cell proliferation was assessed using the CCK-8 proliferation assay and EdU staining. Flow cytometry was employed to assess cell apoptosis, and Western blotting (WB) analysis was conducted to validate the expression of relevant protein markers. mRNA sequencing (mRNA-Seq) was performed on WT cells overexpressing AQP1 to predict and characterize the associated mechanisms. Transmission electron microscopy was utilized to observe changes in the ultrastructure of WT cells undergoing apoptosis and pyroptosis following AQP1 overexpression. Functional in vivo validation was conducted through animal experiments. RESULTS: We validated that overexpression of AQP1 inhibited cell proliferation and promoted cell apoptosis and pyroptosis both in vitro and in vivo. mRNA-Seq analysis of WT cells with AQP1 overexpression suggested that these effects might be mediated through the inhibition of the JAK-STAT signaling pathway. Additionally, we discovered that overexpression of AQP1 activated the classical pyroptosis signaling pathway dependent on caspase-1, thereby promoting pyroptosis in WT. CONCLUSION: These findings highlight the important functional role of AQP1 in the pathobiology of nephroblastoma, providing novel insights into the development of this disease. Moreover, these results offer new perspectives on the potential therapeutic targeting of AQP1 as a treatment strategy for nephroblastoma.

Molecular basis for human aquaporin inhibition.

Cancer invasion and metastasis are known to be potentiated by the expression of aquaporins (AQPs). Likewise, the expression levels of AQPs have been shown to be prognostic for survival in patients and have a role in tumor growth, edema, angiogenesis, and tumor cell migration. Thus, AQPs are key players in cancer biology and potential targets for drug development. Here, we present the single-particle cryo-EM structure of human AQP7 at 3.2-Å resolution in complex with the specific inhibitor compound Z433927330. The structure in combination with MD simulations shows that the inhibitor binds to the endofacial side of AQP7. In addition, cancer cells treated with Z433927330 show reduced proliferation. The data presented here serve as a framework for the development of AQP inhibitors.

Anethole mitigates H2 O2 -induced inflammation in HIG-82 synoviocytes by suppressing the aquaporin 1 expression and activating the protein kinase A pathway.

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease affecting approximately 1% of the global population, with a higher prevalence in women than in men. Chronic inflammation and oxidative stress play pivotal roles in the pathogenesis of RA. Anethole, a prominent compound derived from fennel (Foeniculum vulgare), possesses a spectrum of therapeutic properties, including anti-arthritic, anti-inflammatory, antioxidant, and tumor-suppressive effects. However, its specific impact on RA remains underexplored. This study sought to uncover the potential therapeutic value of anethole in treating RA by employing an H2 O2 -induced inflammation model with HIG-82 synovial cells. Our results demonstrated that exposure to H2 O2 induced the inflammation and apoptosis in these cells. Remarkably, anethole treatment effectively countered these inflammatory and apoptotic processes triggered by H2 O2 . Moreover, we identified the aquaporin 1 (AQP1) and protein kinase A (PKA) pathway as critical regulators of inflammation and apoptosis. H2 O2 stimulation led to an increase in the AQP1 expression and a decrease in p-PKA-C, contributing to cartilage degradation. Conversely, anethole not only downregulated the AQP1 expression but also activated the PKA pathway, effectively suppressing cell inflammation and apoptosis. Furthermore, anethole also inhibited the enzymes responsible for cartilage degradation. In summary, our findings highlight the potential of anethole as a therapeutic agent for mitigating H2 O2 -induced inflammation and apoptosis in synovial cells, offering promising prospects for future RA treatments.

Distributions and expressions of Aquaporin-5 and 7 in the testes of developing male chicks.

Aquaporins (AQPs) are integral membrane proteins that act as water channels for which a total of 13 orthologs of AQP genes in birds have been reported. Tissue expression and cellular or subcellular localization of AQPs have been poorly investigated in the male reproductive system of birds. We aimed to determine the distribution and localization of AQP5 and AQP7 proteins by immunocytochemistry in testicular tissues obtained from developing chicks (14, 21, 28, 35 and 42 days old). Totally 175 male chicks (Ross 308) were used in the study from which testicular tissue was removed, fixed in 10% formaldehyde solution, then embedded in paraffin blocks. Five µm sections were cut, mounted on poly-L-lysine slides, dried in an oven, then dehydrated using standard immunohistochemistry staining protocol. The sections were imaged with a Nikon Eclipse 50i trinocular light microscope. Immunohistochemical evaluation of the immune reactivity of AQP5 revealed a positive immune reaction in spermatocytes and interstitial areas of the testes in 14-day-old chicks. Testicular tissue AQP5 immune reactivity was observed in the tubule and the interstitial regions of 21-, 28-, 35- and 42-day-old chicks. AQP7 immune reactions were determined in the tubule and interstitial areas testes of developing chicks' testis tissue, with increasing positivity corresponding to older age. The expression of AQP5 and AQP7 appears to be species-specific due to differences in localization and expression in male chicks compared with studies of other mammals, which is likely to play an important role in regulating fluid and sperm volume. This research can serve as a base for future studies that will contribute to the understanding of the male genital system of AQPs.

Shen Qi Wan ameliorates nephritis in chronic kidney disease via AQP1 and DEFB1 regulation.

Shen Qi Wan (SQW) has been proven to exert anti-inflammatory effects in the kidneys of CKD models accompanied by unclear therapeutic mechanisms. This study aims to evaluate the kidney-protective and anti-inflammatory effects of SQW and to elucidate its fundamental mechanisms for CKD treatment. Firstly, the main active components of SQW were identified by UPLC-Q-TOF/MS technique. Subsequently, we evaluated inflammatory factors, renal function and renal pathology changes following SQW treatment utilizing adenine-induced CKD mice and aquaporin 1 knockout (AQP1-/-) mice. Additionally, we conducted RNA-seq analysis and bioinformatics analysis to predict the SQW potential therapeutic targets and anti-nephritis pathways. Simultaneously, WGCNA analysis method and machine learning algorithms were used to perform a clinical prognostic analysis of potential biomarkers in CKD patients from the GEO database and validated through clinical samples. Lipopolysaccharide-induced HK-2 cells were further used to explore the mechanism. We found that renal collagen deposition was reduced, serum inflammatory cytokine levels decreased, and renal function was improved after SQW intervention. It can be inferred that ß-defensin 1 (DEFB1) may be a pivotal target, as confirmed by serum and renal tissue samples from CKD patients. Furthermore, SQW assuages inflammatory responses by fostering AQP1-mediated DEFB1 expression was confirmed in in vitro and in vivo studies. Significantly, the renal-protective effect of SQW is to some extent attenuated after AQP1 gene knockout. SQW could reduce inflammatory responses by modulating AQP1 and DEFB1. These findings underscore the potential of SQW as a promising contender for novel prevention and treatment strategies within the ambit of CKD management.

Actin cytoskeleton aggregation involves the water channel protein aquaporin 1-mediated human chondrocyte degeneration.

Water metabolism and actin cytoskeleton remoulding act as essential characters in the process of osteoarthritis (OA). However, the relation between water channel protein aquaporin 1 (AQP1) and actin filament during chondrocytes (CHs) degeneration is not evident. Therefore, the present study aimed to evaluate the role of actin remoulding in the AQP1 mediated CHs degeneration. Primary CHs were collected from human hip cartilage and were degenerated from long-time monolayer culture or IL-1ß stimulation. Besides, the CHs were transfected with AQP1­specific siRNA or vectors to mediate the AQP1 gene expression. The potent inhibitor of actin polymerization Cytochalasin D was also supplemented during culture. RT-PCR was performed to determine the relative gene expression. AQP1 and F-actin fluorescence staining were performed to determine the AQP1 and F-actin organization. Moreover, the cell area and viability were also analyzed. AQP1 and F-actin organization were both increased during seven days' CHs culture or three days' IL-1ß stimulation. Silencing of AQP1 prevented the cell area spreading and degenerated phenotype of CHs with suppression of F-actin aggregation in both natural or IL-1ß-caused inflammatory-related degeneration. Besides, upregulating the AQP1 in the CHs via gene editing promoted the cell area spreading, and F-actin accumulation, and accelerated the CHs degeneration, which can be alleviated by Cytochalasin D treatment. These findings suggested that AQP1-mediated human CHs degeneration is related to F-actin aggregation.

Blood-nerve barrier enhances chronic postsurgical pain via the HIF-1α/ aquaporin-1 signaling axis.

BACKGROUND: Blood nerve barrier (BNB) participates in the development of neuropathic pain. AQP1 is involved in peripheral pain perception and is negatively correlated with HIF-1α phenotype, which regulates endothelial permeability. However, the role of HIF-1α-AQP1-mediated BNB dysfunction in Chronic Postsurgical Pain (CPSP) has not been reported. METHODS: Male Sprague-Dawley rats were randomized into 5 groups: (i) Naive group; (ii) Sham group; (iii) SMIR group: skin/muscle incision and retraction for one hour. Behavioral tests were performed for the three groups, BNB vascular permeability and western blotting were conducted to determine HIF-1α and AQP1 protein expression. (iv) The SMIR + HIF-1α inhibitor group; (v) SMIR + DMSO group. Rats in the two groups were administered with HIF-1α inhibitor (2ME2) or DMSO intraperitoneally on the third day post-SMIR surgery followed by performance of behavioral tests, BNB permeability assessment, and determination of HIF-1α, AQP1 and NF200 protein levels. RESULTS: The permeability of BNB was significantly increased and the expression of AQP1 was downregulated on the 3rd and 7th days post-operation. AQP1 is mainly located in neurons and NF200, CGRP-positive nerve fibers. HIF-1α was highly expressed on the third day post-operation. HIF-1α inhibitor reversed the decrease in AQP1 expression and increase in NF200 expression, barrier permeability and hyperalgesia induced by SMIR on the 3rd day post-surgery. CONCLUSIONS: Early dysfunction of BNB mediated by HIF-1α/AQP1 activated by SMIR may be an important mechanism to promote acute postoperative painful transformation of CPSP. Preadaptive protection of endothelial cells around nerve substructures may be an important countermeasure to inhibit CPSP transformation. Early impairment of BNB function mediated by HIF-1α/AQP1 activated by SMIR may be an important mechanism for promoting acute postoperative pain transformation of CPSP.

Identification of key genes and validation of key gene aquaporin 1 on Wilms' tumor metastasis.

Background: Wilms' tumor (WT) is one of the most common solid tumors in children with unsatisfactory prognosis, but few molecular prognostic markers have been discovered for it. Many genes are associated with the occurrence and prognosis of WT. This study aimed to explore the key genes and potential molecular mechanisms through bioinformatics and to verify the effects of aquaporin 1 (AQP1) on WT metastasis. Methods: Differentially expressed genes (DEGs) were generated from WT gene expression data sets from the Gene Expression Omnibus (GEO) database. Gene functional enrichment analysis was carried out with the Database for Annotation, Visualization and Integrated Discovery (DAVID). A protein-protein interaction network (PPI) was constructed and visualized by the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database and Cytoscape software. Minimal Common Oncology Data Elements (MCODE) was used to detect the important modules in the PPI network, and the important nodes (genes) in the PPI module were sorted by CytoHubba. RT-qPCR was performed to validate the expression of the key genes in WT. Wound healing and Transwell assays were used to detect the cell migration and invasion abilities of AQP1-overexpressing cells. Phalloidin-iFlour 488 was used to stain the cytoskeleton to observe how AQP1 overexpression affects cytoskeletal microfilament structure. Results: A total of 73 co-expressed DEGs were chosen for further investigation. The importance of homeostasis and transmembrane transport of ions and water were highlighted by functional analysis. Gene regulatory network and PPI network were predicted. MCODE plug identified two important modules. Finally, top five key genes were identified using CytoHubba, including Renin (REN), nephrosis 2 (NPHS2), Solute Carrier Family 12 Member 3 (SLC12A3), Solute Carrier Family 12 Member 1 (SLC12A1) and AQP1. The five key genes were mainly enriched in cell volume and ion homeostasis. RT-qPCR confirmed the expression of the five key genes in WT. AQP1 was validated to be expressed at significantly lower levels in WT than in normal tissue. AQP1 overexpression significantly reduced the migratory and invasive capacity of Wit-49 cells, as evidenced by reducing the scratch healing rate and the number of perforated control cells by Wit-49 cells. AQP1 overexpression also reduced the expression of biomarkers of epithelial-mesenchymal transformation, decreased levels of vimentin and N-cadherin and increased expression of E-cadherin, resulting in decreased formation of conspicuous lamellipodial protrusions, characteristic of diminished WT cell invasion and migration. Conclusion: Our study reveals the key genes of WT. These key genes may provide novel insight for the mechanism and diagnosis of WT. AQP1 overexpression inhibited invasion, migration, EMT, and cytoskeletal rearrangement of WT cells, indicating that AQP1 plays a role in the pathogenesis of WT.

Endotoxin induced acute kidney injury modulates expression of AQP1, P53 and P21 in rat kidney, heart, lung and small intestine.

This study was designed to explore whether aquaporin 1(AQP1), P53 and P21 can be used as diagnostic biomarkers of lipopolysaccharide (LPS)-induced acute kidney injury (AKI) and potential indicators of sepsis-induced multiple organ injury. Bioinformatics results demonstrated that AQP1, P53, P21 was dramatically elevated 6h after Cecal ligation and puncture (CLP)-AKI in rat renal tissue. The expression of AQP1, P53, P21, NGAL and KIM-1 in kidney were increased significantly at first and then decreased gradually in LPS-induced AKI rats. Histopathological sections showed swelling of tubular epithelial cells and destruction of basic structures as well as infiltration of numerous inflammatory cells in LPS-induced AKI. Moreover, the expressions of AQP1, P53 and P21 in heart were significantly increased in LPS treatment rats, while the AQP1 expressions in lung and small intestine were significantly decreased. The level of NGAL mRNA in heart, lung and small intestine was firstly increased and then decreased during LPS treatment rats, but the expression of KIM-1 mRNA was not affected. Therefore, our results suggest that AQP1, P53 and P21 is remarkably upregulated in LPS-induced AKI, which may be considered as a potential novel diagnostic biomarker of Septic AKI. NGAL may serve as a biomarker of sepsis-induced multiple organ damage during the process of LPS-induced AKI.

The Role of Aquaporin 1 in Water Retention Mechanism of Arachnoid Cysts: Insights from 3 Case Reports.

BACKGROUND Although arachnoid cysts are common lesions, the pathogenesis of their continuous growth remains unclear. We aimed to identify the role of aquaporins in arachnoid cyst specimens. CASE REPORT We selected 3 cases from our own facility and examined arachnoid cyst wall specimens, which were sampled intraoperatively. Patients presented with variable symptoms, a 52-year-old man with a "heavy sensation" in the head and dysesthesia on the left hand, a 68-year-old man with unsteady gait, and finally a 26-year-old woman with a history of intermittent headaches for 10 years. Intraoperative specimens were obtained and examined. Evaluation techniques were light microscopy, immunohistochemical staining for aquaporin, and electron microscopy. Light microscopy showed that cells were arranged in epithelium-like structures forming several thick lamellae, with visible connective tissue among them. Under electron microscopic examination, cells with many or few cell organelles and with spindle-like nuclei were arranged in lamellar or flattened structures. Many vacuolizations were seen in between. Interdigitation of cells and many desmosomes were observed. All 3 cases were positive for aquaporin 1. CONCLUSIONS Our study showed that water transportation through aquaporin 1 has a potential role in the formation and expansion of arachnoid cysts.

Expression of aquaporin 1, 3 and 5 in colorectal carcinoma: correlation with clinicopathological characteristics and prognosis.

Background: Prognostic biomarkers in colorectal carcinoma (CRC) have an important role in therapeutic strategy. Studies have shown that high expression of Aquaporin (AQP) is associated with poor prognosis in a variety of human tumors. AQP is involved in the initiation and development of CRC. The present study aimed to investigate the correlation between the expression of AQP1, 3 and 5 and clinicopathological features or prognosis in CRC. Methods: The AQP1, 3 and 5 expressions were analyzed based on the immunohistochemical staining of tissue microarray specimens including 112 patients with CRC between June 2006 and November 2008. The expression score of AQP (Allred_score and H_score) was digitally obtained with Qupath software. Patients were divided into high or low expression subgroups based on the optimal cut-off values. The relationship between expression of AQP and clinicopathological characteristics were evaluated using chi-square test, t-test, or one-way ANOVA, when appropriate. Survival analysis of 5-year progression free survival (PFS) and overall survival (OS) was performed with time-dependent ROC, Kaplan-Meier curves, univariate and multivariate COX analysis. Results: The AQP1, 3 and 5 expressions were associated with regional lymph node metastasis, histological grading, and tumor location in CRC, respectively (p < 0.05). Kaplan-Meier curves showed that patients with high AQP1 expression had worse 5-year PFS than those with low AQP1 expression (Allred_score: 47% vs. 72%, p = 0.015; H_score: 52% vs. 78% p = 0.006), as well as 5-year OS (Allred_score: 51% vs. 75%, p = 0.005; H_score: 56% vs. 80%, p = 0.002). Multivariate Cox regression analysis indicated that AQP1 expression was an independent risk prognostic factor (p = 0.033, HR = 2.274, HR95% CI: 1.069-4.836). There was no significant correlation between the expression of AQP3 and 5 and the prognosis. Conclusion: The AQP1, 3 and 5 expressions correlate with different clinicopathological characteristics and the AQP1 expression may be a potential biomarker of prognosis in CRC.

Tanshinone IIA changed the amniotic fluid volume and regulated expression of AQP1 and AQP3 in amniotic epithelium cells: a promising drug treating abnormal amniotic fluid volume.

BACKGROUND: Many studies have confirmed the association of aquaporins (AQPs) with abnormal amniotic fluid volume (AFV). In our previous experiments, we found that Tanshinone IIA was able to regulate the expression of AQP1 and AQP3. However, the exact mechanism by which Tanshinone IIA regulates AQPs protein expression and its effect on AFV remains unclear. The purpose of this study was to investigate the effects of Tanshinone IIA on AFV and the possible molecular mechanism of regulation of AQP1 and AQP3. METHODS: The expression of AQPs protein in the amniotic membranes was compared between pregnant women with normal pregnancy and those with isolated oligohydramnios. The AQP1 knockout (AQP1-KO) mice and wild-type (WT) mice were treated with saline or Tanshinone IIA (10 mg/kg) at 13.5GD and 16.5GD. Human amniotic epithelium cells (hAECs) from pregnant women with normal AFV and isolated oligohydramnios were incubated with 35 µmmol/L Tanshinone IIA or 25 mmol/L LiCl [inhibitor of glycogen synthetic kinase 3ß (GSK-3ß)]. The protein expressions of AQPs, GSK-3ß, phospho-GSK-3ß (Ser9) in fetal membranes of mice and human amniotic epithelium cells were detected by western blotting. RESULTS: The expression of AQP1 protein in the amniotic membrane of isolated oligohydramnios was increased compared with normal pregnancy. The AFV in AQP1-KO mice is higher than that in WT mice. In wild-type mice, AFV in Tanshinone IIA group was significantly higher than that in control group, and AQP1 protein expression was significantly lower than that in control group, but in AQP1 knockout mice, Tanshinone IIA reduced amniotic fluid volume and AQP3 protein expression at 16.5GD. Tanshinone IIA reduced AQP1, AQP3 and p-GSK-3ß (Ser9) protein expression in normal hAECs, and this effect was inhibited by LiCl. In hAECs with oligohydramnios, the down-regulation of AQP1 and up-regulation of AQP3 by Tanshinone IIA was independent of GSK-3ß signaling pathway. CONCLUSIONS: Tanshinone IIA may increase AFV in normal pregnancy by downregulating AQP1 protein expression in the fetal membranes, which may be associated with p-GSK-3ß signaling pathway. But a larger AFV in AQP1-KO mice was significantly attenuated by Tanshinone IIA, which may be related to AQP3. Tanshinone IIA is a promising drug for the treatment of amniotic fluid abnormality.

Aquaporin 1 Facilitates Ferroptosis, M1 Polarization, Mitochondrial Dysfunction, and Autophagy Damage on Lipopolysaccharide-Induced Macrophage Through Down-Regulation of P53 Signaling Pathway.

This study was designed to investigate the role of aquaporin 1 (AQP1) in ferroptosis, macrophage polarization, mitochondrial dysfunction, and impaired autophagy of lipopolysaccharide (LPS)-stimulated RAW264.7 cells and explored the underlying mechanisms. Si-AQP1-mediated AQP1 silencing RAW264.7 cells was constructed. Si-P53-mediated P53 silencing or pcDNA-P53 overexpression RAW264.7 cells was constructed. Assays of ATP, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and Mitochondrial membrane potential (JC-1) staining were performed to evaluate mitochondrial biological function. Assays of flow cytometry, reactive oxygen species (ROS) staining, western blot (WB), RT-qPCR, malondialdehyde (MDA), glutathione (GSH), and total superoxide dismutase (SOD) were performed to detect cell ferroptosis, macrophage polarization, and impaired autophagy. The involvement of the P53 pathway was revealed by WB. The results showed that LPS (30 µg/mL) could induce ferroptosis, M1 polarization, mitochondrial dysfunction, and autophagy damage in RAW264.7 cells. Meanwhile, the expression of AQP1 was increased and the expression of P53 was decreased. In addition, Pifithrin-α (PIF; 15 µM), a P53 inhibitor, significantly aggravated ferroptosis, M1 polarization, mitochondrial dysfunction, and autophagy damage as well as up-regulation of AQP1 protein expression in LPS-induced RAW264.7 cells. Interestingly, this phenomenon was markedly alleviated by Kevetrin hydrochloride (70 µM), a P53 agonist. Mechanistically, silencing AQP1 significantly alleviated ferroptosis, M1 polarization, mitochondrial dysfunction, and autophagy damage by up-regulating the expression of P53 in LPS-stimulated RAW264.7 cells. Indeed, inhibition of P53 expression by PIF treatment dramatically reversed this effect on the basis of LPS+si-AQP1. Therefore, we concluded for the first time that AQP1 can promote ferroptosis, M1 polarization, mitochondrial dysfunction, and autophagy impairment by inhibiting the expression of P53 in LPS-stimulated RAW264.7 cells, and AQP1 or P53 may be considered as a crucial determiner that can regulate the biological behavior of RAW264.7 cells stimulated by LPS.

Shen Qi Wan attenuates renal interstitial fibrosis through upregulating AQP1.

Renal interstitial fibrosis (RIF) is the crucial pathway in chronic kidney disease (CKD) leading to the end-stage renal failure. However, the underlying mechanism of Shen Qi Wan (SQW) on RIF is not fully understood. In the current study, we investigated the role of Aquaporin 1 (AQP1) in SQW on tubular epithelial-to-mesenchymal transition (EMT). A RIF mouse model induced by adenine and a TGF-ß1-stimulated HK-2 cell model were etablished to explore the involvement of AQP 1 in the protective effect of SQW on EMT in vitro and in vivo. Subsequently, the molecular mechanism of SQW on EMT was explored in HK-2 cells with AQP1 knockdown. The results indicated that SQW alleviated kidney injury and renal collagen deposition in the kidneys of mice induced by adenine, increased the protein expression of E-cadherin and AQP1 expression, and decreased the expression of vimentin and α-smooth muscle actin (α-SMA). Similarly, treatmement with SQW-containing serum significantly halted EMT process in TGF-ß1 stimulated HK-2 cells. The expression of snail and slug was significantly upregulated in HK-2 cells after knockdown of AQP1. AQP1 knockdown also increased the mRNA expression of vimentin and α-SMA, and decreased the expression of E-cadherin. The protein expression of vimentin increased, while the expression of E-cadherin and CK-18 significantly decreased after AQP1 knockdown in HK-2 cells. These results revealed that AQP1 knockdown promoted EMT. Furthermore, AQP1 knockdown abolished the protective effect of SQW-containing serum on EMT in HK-2 cells. In sum, SQW attentuates EMT process in RIF through upregulation of the expression of AQP1.

XinLi formula, a traditional Chinese decoction, alleviates chronic heart failure via regulating the interaction of AGTR1 and AQP1.

BACKGROUND: XinLi formula (XLF) is a traditional Chinese medicine used in clinical practice to treat chronic heart failure (CHF) in humans, with remarkable curative effect. However, the mechanism remains unknown. PURPOSE: The goal of the current investigation was to determine how XLF affected CHF in a rat model of the condition brought on by ligation of the left anterior descending coronary artery, and to investigate the underlying mechanism. STUDY DESIGN AND METHODS: Cardiac function was detected by echocardiography. The contents of myocardial enzymes, Ang II, ALD, TGF-ß1, and inflammatory factors were measured by ELISA. Myocardial injury and myocardial fibrosis were evaluated by HE and Masson staining. Myocardial edema was assessed by cardiac mass index and transmission electron microscopy. Using Western blot and immunohistochemistry to examining the protein expression of inflammasome, TGF-ß1, AGTR1, and AQP1 in the left ventricle. Furthermore, the interaction of AGTR1 and AQP1 was evaluated by co-immunoprecipitation. RESULTS: XLF attenuated myocardial enzymes and myocardial injury, and improved cardiac function in rats with CHF after myocardial infarction. It also reduced Ang II and ALD levels in CHF rats, and suppressed the expression of AGTR1 and TGF-ß1, finally alleviated myocardial fibrosis. By mechanism, XLF inhibited the expression of NLRP3 inflammasome proteins, reduced the plasma contents of IL-1ß, IL-18, IL-6 and TNF-α. Additionally, XLF inhibited the expression of AQP1 and the interaction of AGTR1 and AQP1, alleviating myocardial edema. The common structure of the main chemical constituents of XLF were glycoside compounds with glycosyl. CONCLUSION: XLF ameliorated CHF, which was evidenced by the alleviation of myocardial fibrosis by inhibiting AGTR1/NLRP3 signal, as well as the attenuation of myocardial edema by suppressing the interaction of AGTR1 and AQP1.