TMEM16A Research Articles

High level of ANO1 promotes pancreatic cancer growth in concert with oncogenic KRAS.

Anoctamin-1 (ANO1) was identified as an unfavorable prognostic marker in pancreatic cancer. However, the exact implication of ANO1 in pancreatic cancer is still poorly understood. Here we investigated the effect of ANO1 in pancreatic cancer progression under the context of oncogenic KRAS, aiming at finding a new therapeutic target. Knockdown and overexpression of oncogenic KRAS as well as ANO1 in PDAC cell lines were performed by lentivirus infection. Cell proliferation and migration assay, RNA seq analysis were performed in PDAC cells bearing different status of ANO1 and KRAS. In vivo mice model was used to investigate the xenograft tumor growth with different status of KRAS and ANO1. Our results showed that ANO1 expression level is elevated in poorly differentiated cancer cells. Overexpression of ANO1 in PDAC cancer cells was found to promote cancer cell proliferation in vitro and in vivo, which synergized with the introduction of oncogenic KRAS. Consistently, knockdown of ANO1 expression was found to suppress cancer growth in vitro and in vivo. RNA seq analysis revealed that the observed synergistic cancer-promoting effect from ANO1 and oncogenic KRAS is likely due to concurrent activating key genes involved in lipid metabolism including HMGCS1. The outcome from our study suggests that ANO1 plays an important role in promoting pancreatic cancer development, especially at the presence of oncogenic KRAS. Considering the prevalence of KRAS mutation in pancreatic cancer patients, suppression ANO1 may represent a potential effective therapeutic measure in pancreatic cancer treatment.

DOG1 as a novel antibody-drug conjugate target for the treatment of multiple gastrointestinal tumors and liver metastasis.

Discovered On Gastrointestinal stromal tumors protein 1 (DOG1), a major calcium-activated chloride channel, has been used as a common diagnostic marker for gastrointestinal stromal tumors. However, the therapeutic application of DOG1 was not well defined. Here, we aim to investigate its potential as a therapeutic target for an antibody-drug conjugate (ADC) in various cancers of the alimentary tract and metastasis. The DOG1 expression profile was determined among TCGA samples and tissue microarrays. High levels of DOG1 expression were ubiquitously observed in multiple cancer samples from the alimentary tract determined by TCGA samples and tissue microarrays. Circulating tumor cells isolated from metastatic colon cancer patients were also positive for DOG1 expression. The mechanisms of anti-DOG1 antibody were investigated by dual-luciferase reporter assay. The anti-DOG1 antibody could inhibit proliferation and metastasis via p53 signaling in limited cancer cell lines. The anti-DOG1 antibody was conjugated with a microtubule inhibitor DM4, to construct a new anti-DOG1-DM4-ADC to strengthen its activity. The anti-DOG1-DM4-ADC showed cytotoxicity at the nanomolar level in vitro. In the murine xenograft tumor models, treatment of anti-DOG1-DM4-ADC achieved a significant tumor growth inhibition rate. Our study indicates that anti-DOG1-DM4-ADC may be promising therapeutic molecules for DOG1-positive alimentary tract tumors and may be effective in inhibiting recurrence after curative resection of liver metastases of colorectal origin.

TRPV3-ANO1 interaction positively regulates wound healing in keratinocytes

Transient receptor potential vanilloid 3 (TRPV3) belongs to the TRP ion channel super family and functions as a nonselective cation channel that is highly permeable to calcium. This channel is strongly expressed in skin keratinocytes and is involved in warmth sensation, itch, wound healing and secretion of several cytokines. Previous studies showed that anoctamin1 (ANO1), a calcium-activated chloride channel, was activated by calcium influx through TRPV1, TRPV4 or TRPA1 and that these channel interactions were important for TRP channel-mediated physiological functions. We found that ANO1 was expressed by normal human epidermal keratinocytes (NHEKs). We observed that ANO1 mediated currents upon TRPV3 activation of NHEKs and mouse skin keratinocytes. Using an in vitro wound-healing assay, we observed that either a TRPV3 blocker, an ANO1 blocker or low chloride medium inhibited cell migration and proliferation through p38 phosphorylation, leading to cell cycle arrest. These results indicated that chloride influx through ANO1 activity enhanced wound healing by keratinocytes.

Hydrochemical characteristics and water quality assessment of snow cover in the northeastern tibet plateau

Snow cover as an important water resource is essential for regional water environment system. The Three-Rivers Headwater Region (THR) in the Tibetan Plateau is the source of the Yellow River, the Yangtze River and the Lantsang River with fragile ecological environment and large snow cover. The analysis of hydrochemistry in snow cover can provide reliable data for the research of environmental changes. Snow cover samples in 57 sites across the THR region were collected, and arsenic (As) and major ions were analyzed to investigate the distribution characteristics. The snow cover samples were weakly alkaline with water type of SO4–Cl–Ca–Mg. The As concentration varied from 0.24 to 6.12 μg/L with average value of 1.25 μg/L. Major ions and As have similar distribution characteristics, with higher levels in the northern part of the study area due to anthropogenic influence and special geography. Qualitative and semi-quantitative analysis of snow cover samples based on principal component analysis and absolute principal component score-multiple linear regression indicated that As was substantially controlled by burning of fossil fuels and local mining activities, while major ions mainly derived from terrestrial dust, human activities and marine sources. Although there were different trajectories at the sampling points, the air mass in THR was mainly controlled by the westerly circulation. The water quality of THR was excellent with water quality index <50. This work will shed lights for the migration and transformation of pollutants in the Tibet Plateau and for assessing the impact of human activities on geochemical cycling of pollutants.

Solithromycin inhibits IL-13-induced goblet cell hyperplasia and MUC5AC, CLCA1, and ANO1 in human bronchial epithelial cells.

Solithromycin is a novel fluoroketolide antibiotic belonging to the class of macrolide antibiotics. Activation of the interleukin (IL)-13 receptor leads to STAT6 activation and subsequent induction of SAM pointed domain containing ETS transcription factor (SPDEF), chloride channel accessory 1 (CLCA1), and anoctamin-1 (ANO1), all of which are associated with the induction of MUC5AC. We examined the effects of solithromycin on mucin production led by IL-13 signaling. Normal human bronchial epithelial cells were grown at the air-liquid interface with IL-13 with/without solithromycin for 14 days. Histochemical analysis was performed using hematoxylin and eosin staining and MUC5AC immunostaining. MUC5AC, SPDEF, CLCA1, and ANO1 mRNA expressions were examined using real-time polymerase chain reaction. Western blot analysis was performed to assess CLCA1 and ANO1 proteins, and phosphorylation of STAT6 and ERK. Solithromycin attenuated IL-13 induction of goblet cell hyperplasia and MUC5AC, CLCA1 and ANO1 mRNA and protein expression induced by IL-13, but had no effect on the phosphorylation of STAT6 and ERK. Our results indicate that solithromycin could attenuate goblet cell hyperplasia and MUC5AC induced by IL-13 through inhibition of CLCA1 and ANO1 mRNA and protein expression. However, much more information is required to clarify the molecular mechanisms underlying the inhibition of CLCA1 and ANO1 by solithromycin.

Computational modeling of anoctamin 1 calcium-activated chloride channels as pacemaker channels in interstitial cells of Cajal

The system of equations and figures presented in the primary paper (Lees Green et al, 2014) are verified and reproduced in this paper’s curation effort. We describe here the model encoding in the CellML format and document the differences between this encoding and the published model (Lees Green et al, 2014) to demonstrate reproducibility.

Inhibition of ANO1 by Cis- and Trans-Resveratrol and Their Anticancer Activity in Human Prostate Cancer PC-3 Cells.

Anoctamin1 (ANO1), a calcium-activated chloride channel, is involved in the proliferation, migration, and invasion of various cancer cells including head and neck squamous cell carcinoma, lung cancer, and prostate cancer. Inhibition of ANO1 activity or downregulation of ANO1 expression in these cancer cells is known to exhibit anticancer effects. Resveratrol, a natural polyphenol abundant in wines, grapes, berries, soybeans, and peanuts, shows a wide variety of biological effects including anti-inflammatory, antioxidant, and anticancer activities. In this study, we investigated the effects of two stereoisomers of resveratrol on ANO1 activity and found that cis- and trans-resveratrol inhibited ANO1 activity with different potencies. Cis- and trans-resveratrol inhibited ANO1 channel activity with IC50 values of 10.6 and 102 μM, respectively, and had no significant effect on intracellular calcium signaling at 10 and 100 μM, respectively. In addition, cis-resveratrol downregulated mRNA and protein expression levels of ANO1 more potently than trans-resveratrol in PC-3 prostate cancer cells. Cis- and trans-resveratrol significantly reduced cell proliferation and cell migration in an ANO1-dependent manner, and both resveratrol isomers strongly increased caspase-3 activity, PARP cleavage, and apoptotic sub-G1 phase ratio in PC-3 cells. These results revealed that cis-resveratrol is a potent inhibitor of ANO1 and exhibits ANO1-dependent anticancer activity against human metastatic prostate cancer PC-3 cells.

Luteolin ameliorates loperamide-induced functional constipation in mice.

Functional constipation (FC) is one of the most common gastrointestinal disorders characterized by hard stools and infrequent bowel movements, which is associated with dysfunction of the enteric nervous system and intestinal motility. Luteolin, a naturally occurring flavone, was reported to possess potential pharmacological activities on intestinal inflammation and nerve injury. This study aimed to explore the role of luteolin and its functional mechanism in loperamide-induced FC mice. Our results showed that luteolin treatment reversed the reduction in defecation frequency, fecal water content, and intestinal transit ratio, and the elevation in transit time of FC models. Consistently, luteolin increased the thickness of the muscular layer and lessened colonic histopathological injury induced by loperamide. Furthermore, we revealed that luteolin treatment increased the expression of neuronal protein HuC/D and the levels of intestinal motility-related biomarkers, including substance P (SP), vasoactive intestinal polypeptide (VIP), and acetylcholine (ACh), as well as interstitial cells of Cajal (ICC) biomarker KIT proto-oncogene, receptor tyrosine kinase (C-Kit), and anoctamin-1 (ANO1), implying that luteolin mediated enhancement of colonic function and contributed to the anti-intestinal dysmotility against loperamide-induced FC. Additionally, luteolin decreased the upregulation of aquaporin (AQP)-3, AQP-4, and AQP-8 in the colon of FC mice. In summary, our data showed that luteolin might be an attractive option for developing FC-relieving medications.

Phosphatidylinositol 4,5-Bisphosphate and Cholesterol Regulators of the Calcium-Activated Chloride Channels TMEM16A and TMEM16B.

Chloride fluxes through homo-dimeric calcium-activated channels TMEM16A and TMEM16B are critical to blood pressure, gastrointestinal motility, hormone, fluid and electrolyte secretion, pain sensation, sensory transduction, and neuronal and muscle excitability. Their gating depends on the voltage-dependent binding of two intracellular calcium ions to a high-affinity site formed by acidic residues from α-helices 6-8 in each monomer. Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a low-abundant lipid of the inner leaflet, supports TMEM16A function; it allows TMEM16A to evade the down-regulation induced by calcium, poly-L-lysine, or PI(4,5)P2 5-phosphatase. In stark contrast, adding or removing PI(4,5)P2 diminishes or increases TMEM16B function, respectively. PI(4,5)P2-binding sites on TMEM16A, and presumably on TMEM16B, are on the cytosolic side of α-helices 3-5, opposite the calcium-binding sites. This modular structure suggested that PI(4,5)P2 and calcium cooperate to maintain the conductive state in TMEM16A. Cholesterol, the second-largest constituent of the plasma membrane, also regulates TMEM16A though the mechanism, functional outcomes, binding site(s), and effects on TMEM16A and TMEM16B remain unknown.

Evaluation of incidence of the adult-onset vitelliform macular dystrophy among patients in Far Eastern Federal District of Russia

BACKGROUND: Adult-onset vitelliform macular dystrophy is one of the pathologic conditions , which successfully masks as age-related macular degeneration.&#x0D; AIM: To assess the incidence of the adult-onset vitelliform macular dystrophy among patients of a major ophthalmological clinic in the Far Eastern Federal District of Russia.&#x0D; MATERIALS AND METHODS: We revealed the cases of adult-onset vitelliform macular dystrophy among 1000 patients aged 40 years and older who addressed for various ocular complaints.&#x0D; RESULTS: Adult-onset vitelliform macular dystrophy was found in 2 male patients aged 43 and 66 years. In the macular area of both eyes of the 1st patient, round yellow lesions in the foveola, local detachment of neuroepithelium, optically dense material deposits on the outer photoreceptor segments were detected (vitelliruptive stage of adult-onset vitelliform macular dystrophy). In the left eye of the 2nd patient, in the foveola, a single round yellow focus of 200 m was found, optically dense vitelliform material was detected between the pigment epithelium and neuroepithelium layers without any signs of choroidal neovascularization (vitelliform stage of adult-onset vitelliform macular dystrophy).&#x0D; CONCLUSIONS: The incidence of adult-onset vitelliform macular dystrophy among patients with various ocular conditions was 0.2%. Morphological changes in the macula consist in presence of deposits of vitelliform material, localized between the neuroepithelium and retinal pigment epithelium layers.

A novel compound heterozygous BEST1 gene mutation in two siblings causing autosomal recessive bestrophinopathy

PurposeTo describe the clinical features, imaging characteristics, and genetic test results associated with a novel compound heterozygous mutation of the BEST1 gene in two siblings with autosomal recessive bestrophinopathy.MethodsTwo siblings underwent a complete ophthalmic examination, including dilated fundus examination, fundus photography, fundus autofluorescence imaging, spectral-domain optical coherence tomography, fluorescein angiography, electroretinography, and electrooculography. A clinical diagnosis of autosomal recessive bestrophinopathy was established based on ocular examination and multimodal retinal imaging. Subsequently, clinical exome sequencing consisting of a panel of 6670 genes was carried out to confirm the diagnosis and assess genetic alterations in the protein-coding region of the genome of the patients. The identified mutations were tested in the two affected siblings and one of their parents.ResultsTwo siblings (a 17-year-old female and a 15-year-old male) presented with reduced visual acuity and bilaterally symmetrical subretinal deposits of hyperautofluorescent materials in the posterior pole, which showed staining in the late phase of fluorescein angiogram. Spectral-domain optical coherence tomography demonstrated hyperreflective subretinal deposits and subretinal fluid accumulation. Both patients shared two mutations in the protein-coding region of the BEST1 gene, c.103G > A, p.(Glu35Lys) and c.313C > A, p.(Arg105Ser) (a novel disease-causing mutation). Sanger sequencing confirmed that the unaffected mother of the proband was carrying p.(Glu35Lys) variant in a heterozygous state.ConclusionsWe have identified and described the phenotype of a novel disease-causing mutation NM_004183.4:c.313C > A, p.(Arg105Ser) in a heterozygous state along with a previously reported mutation NM_004183.4:c.103G > A, p.(Glu35Lys) of the BEST1 gene in two related patients with autosomal recessive bestrophinopathy.

Glial regulators of ions and solutes required for specific chemosensory functions in Caenorhabditis elegans.

Glia and accessory cells regulate the microenvironment around neurons and primary sensory cells. However, the impact of specific glial regulators of ions and solutes on functionally diverse primary cells is poorly understood. Here, we systemically investigate the requirement of ion channels and transporters enriched in Caenorhabditis elegans Amsh glia for the function of chemosensory neurons. Although Amsh glia ablated worms show reduced function of ASH, AWC, AWA, and ASE neurons, we show that the loss of glial enriched ion channels and transporters impacts these neurons differently, with nociceptor ASH being the most affected. Furthermore, our analysis underscores the importance of K+, Cl-, and nucleoside homeostasis in the Amphid sensory organ and uncovers the contribution of glial genes implicated in neurological disorders. Our findings build a unique fingerprint of each glial enriched ion channel and transporter and may provide insights into the function of supporting cells of mammalian sensory organs.

Anoctamins and Calcium Signalling: An Obstacle to EGFR Targeted Therapy in Glioblastoma?

Glioblastoma is the most common form of high-grade glioma in adults and has a poor survival rate with very limited treatment options. There have been no significant advancements in glioblastoma treatment in over 30 years. Epidermal growth factor receptor is upregulated in most glioblastoma tumours and, therefore, has been a drug target in recent targeted therapy clinical trials. However, while many inhibitors and antibodies for epidermal growth factor receptor have demonstrated promising anti-tumour effects in preclinical models, they have failed to improve outcomes for glioblastoma patients in clinical trials. This is likely due to the highly plastic nature of glioblastoma tumours, which results in therapeutic resistance. Ion channels are instrumental in the development of many cancers and may regulate cellular plasticity in glioblastoma. This review will explore the potential involvement of a class of calcium-activated chloride channels called anoctamins in brain cancer. We will also discuss the integrated role of calcium channels and anoctamins in regulating calcium-mediated signalling pathways, such as epidermal growth factor signalling, to promote brain cancer cell growth and migration.

Establishment of a CaCC-based Cell Model and Method for High-throughput Screening of M3 Receptor Drugs.

Muscarinic acetylcholine receptor subtype 3 (M3 receptor) is a G Protein-Coupled Receptor (GPCR) that mediates many important physiological functions. Currently, most M3 receptor drugs also have high affinity for other subtypes of muscarinic acetylcholine receptors (mAChRs) and produce the risk of side effects. Therefore, in order to find M3 receptor drugs with high specificity, high activity and low side effects, we established a cell model and method for efficient and sensitive screening of M3 receptor based on calcium-activated chloride channels (CaCCs), and this method is also suitable for the screening of other GPCR drugs. This screening model consists of Fischer rat thyroid follicular epithelial (FRT) cells that endogenously express M3 receptors, CaCCs, and the indicator YFP-H148Q/I152L. We verified that the model can sensitively detect changes in intracellular Ca2+ concentration using fluorescence quenching kinetics experiments, confirmed the screening function of the model by applying available M3 receptor drugs, and also evaluated the good performance of the model in high-throughput screening.

BEST1 novel mutation causes Bestrophinopathies in six families with distinct phenotypic diversity.

To report novel BEST1 variants in six Chinese families with bestrophinopathies of two different inheritance modes and analyze the intrafamilial phenotypic diversity. A total of 25 participants including 13 patients and 12 healthy family members from 6 Chinese families with bestrophinopathies were available for genetic and clinical analysis. All of the patients were subjected to comprehensive ophthalmic evaluations and exome sequencing was performed on the probands to detect the causative variants. The pathogenicity of gene variants was predicted using silico analysis and evaluated according to ACMG guidelines. All (likely) pathogenic variants were determined by Sanger sequencing and co-segregation analyses were performed on available family members. The relevant original literature previously reported was retrieved to explore the relationship between BEST1-related gene variants and clinical features. In the 6 families, 3 families (10 patients) were assigned as autosomal dominant bestrophinopathies (VMD) and 3 families (3 patients) were assigned as Autosomal recessive Bestrophinopathies (ARB). A total of 9 variants on the BEST1 gene were identified, containing 7 missense variants, 1 nonsense variant, and 1 frameshift variant, respectively, of which 3 variants c.88A > G (p.Lys30Glu), c.764G > A (p.Arg255Gln) and c.233dupT (p.Ser79Phefs*153) were novel variants. Three families with ARB were detected with heterozygous variants on the BEST1 gene.2 families (8 patients) with BVMD showed markedly irregular dominant inheritance, and the severity of macular lesions varies greatly among individuals of the same family. Among them, the probands showed typical vitelliform lesions in the macula, while the other six patients had no visible signs of the disease by fundus photography (ophthalmoscopy) and minor lesions could be detected on OCT in two patients, the continuity of the ellipsoidal band was interrupted with the chimeric band. The phenotypes of the patients in the three ARB families ranged from typical/atypical vitelliform lesions to extensive extramacular deposits (peripheral spots). This study provided evidence that the phenotype of BVMD manifested irregular dominant inheritance, with patients carrying a pathogenic heterozygous variant of BEST1 to develop obvious intrafamilial phenotypic diversity, and the patients who harbor two pathogenic alleles showed recessive inheritance bestrophinopathies with distinct phenotypic diversity. Our study also emphasized the importance of comprehensive genetic analysis in patients with bestrophinopathies, and in such challenging families with distinct intrafamilial phenotypic diversity, it shall provide novel insights into phenotypic assessments of bestrophinopathies, and contribute to better diagnosis, prognosis, and treatment for these patients.

Corticotropin-releasing factor receptor agonists decrease interstitial cells of Cajal in murine colon.

Peripheral corticotropin-releasing factor (CRF) has been reported to affect gastrointestinal motility through corticotropin-releasing factor receptor located in enteric nervous system (ENS), but less is known about of the relationship between peripheral CRF and interstitial cells of Cajal (ICC). Mice were intraperitoneally injected with CRF receptor agonists to determine their effects on colonic ICC. Chronic heterotypic stress (CHeS) was applied to mice to determine endogenous CRF-CRF receptor signaling on colonic ICC. We found that stressin1, a selective CRF receptor 1 (CRF1 ) agonist, significantly increased the expression of CRF1 but had no effect on the expression of CRF2 in the smooth muscles of murine colon. The protein expression of c-Kit, Anoctamin-1 (ANO1), and stem cell factor (SCF) in the colonic smooth muscles was significantly decreased in stressin1-treated mice. Accordingly, 2-(4-Chloro-2-methylphenoxy)-N'-(2-methoxybenzylidene) acetohydrazide (Ani 9), a selective ANO1 blocker, had a less significant inhibitory effect on CMMC in stressin1-treated mice compared to the saline-treated ones. Similarly, we also found that ICC and ANO1 were reduced in the colonic smooth muscles of mice by treatment with sauvagine (ip), a CRF2 agonist. However, different with stressin1, sauvagine decreased the expression of CRF2 besides increasing CRF1 expression in the colonic smooth muscles. Similar results of CRF1 and c-Kit expressions were also obtained from the colon of CHeS-treated mice. All these results suggest that CRF may be involved in the abnormality of colonic motility through peripheral CRF1 to decrease the number and function of ICC, which provides a potential target for treating stress-induced gastrointestinal motility disorder.

CLCA2 overexpression suppresses epithelial-to-mesenchymal transition in cervical cancer cells through inactivation of ERK/JNK/p38-MAPK signaling pathways

Cervical cancer is an important malignant tumor threatening the physical and mental health of women in the world. As a new calcium activated chloride channel protein, calcium activated chloride channel (CLCA2) plays an important role in tumorigenesis and development. But its role and exact regulatory mechanism in cervical cancer are still unclear. In our study, we found CLCA2 was significantly decreased in cervical cancer cells, and overexpression of CLCA2 inhibited the proliferation, migration and invasion, and promotes apoptosis of cervical cancer cells, and CLCA2 inhibited EMT (Epithelial-mesenchymal transition) through an p38 / JNK / ERK pathway. The results in vivo were consistent with those in vitro. In conclusion, overexpression of CLCA2 inhibited the progression of cervical cancer in vivo and in vitro. This may provide a theoretical basis for CLCA2 as a new indicator of clinical diagnosis and prognosis of cervical cancer or as a potential target of drug therapy.

Anoctamin 5 (ANO5) Muscle Disorders: A Narrative Review.

Anoctaminopathy-5 refers to a group of hereditary skeletal muscle or bone disorders due to mutations in the anoctamin 5 (ANO5)-encoding gene, ANO5. ANO5 is a 913-amino acid protein of the anoctamin family that functions predominantly in phospholipid scrambling and plays a key role in the sarcolemmal repairing process. Monoallelic mutations in ANO5 give rise to an autosomal dominant skeletal dysplastic syndrome (gnathodiaphyseal dysplasia or GDD), while its biallelic mutations underlie a continuum of four autosomal recessive muscle phenotypes: (1). limb–girdle muscular dystrophy type R12 (LGMDR12); (2). Miyoshi distal myopathy type 3 (MMD3); (3). metabolic myopathy-like (pseudometabolic) phenotype; (4). asymptomatic hyperCKemia. ANO5 muscle disorders are rare, but their prevalence is relatively high in northern European populations because of the founder mutation c.191dupA. Weakness is generally asymmetric and begins in proximal muscles in LGMDR12 and in distal muscles in MMD3. Patients with the pseudometabolic or asymptomatic hyperCKemia phenotype have no weakness, but conversion to the LGMDR12 or MMD3 phenotype may occur as the disease progresses. There is no clear genotype–phenotype correlation. Muscle biopsy displays a broad spectrum of pathology, ranging from normal to severe dystrophic changes. Intramuscular interstitial amyloid deposits are observed in approximately half of the patients. Symptomatic and supportive strategies remain the mainstay of treatment. The recent development of animal models of ANO5 muscle diseases could help achieve a better understanding of their underlying pathomechanisms and provide an invaluable resource for therapeutic discovery.

Probabilistic potential health risk quantification, hydrochemistry, driving forces of groundwater nitrate and fluoride in a typical irrigation district, Northern China

Groundwater is the foremost water source of agricultural irrigation areas in northern China. However, the problem from excessive geogenic fluoride and anthropogenic nitrate in groundwater and its potential health risks are often neglected. This paper aims to identify the health threats, water quality and hydrochemistry in Weibei Plain, northern China. A total of 50 water samples collected in May 2021 were assessed by hydrogeochemical analysis, the entropy weight water quality index method and probabilistic human health risk assessment based on Monte Carlo stochastic simulation. The results showed that the hydrochemical type of surface water and groundwater was mainly SO4·Cl–Ca·Mg type. The rock weathering and cation exchanges were found to the important processes influencing hydrochemistry. The quality of surface water was higher than that of groundwater, with Class IV and Class V groundwater samples concentrated in the northwest of the study area. The F− concentration in groundwater samples generally exceeded the drinking water standard, which mainly came from mineral dissolution affected by excessive irrigation. Nitrate pollution in groundwater has regional characteristics, mainly from agricultural activities. Long−term use of groundwater might bring risks to residents' health, because more than 65% and 23% of groundwater samples exceeded the acceptable non−carcinogenic risk limits of F− and NO3− to children, respectively. Considering the uncertainty of model parameters, children will have a probability of more than 46.9% and 12.6% to face F− and NO3− risks in groundwater. Compared with NO3−, the high concentration of F− in groundwater posed a higher threat to human health, and children faced higher risks. Compared with the deterministic method, the stochastic simulation can more accurately reflect health risks. The findings of this study can help policymakers devise strategies to ensure a safe supply of domestic water.

Generation of two TMEM16A knockout iPSC clones each from a healthy human iPSC line, from a Cystic Fibrosis patient specific line with p.Phe508del mutation and from the gene corrected iPSC line

The Transmembrane member 16A (TMEM16A), also known as anoctamin-1 (ANO1), is a calcium-activated chloride channel present in the airway epithelium. It is known to be involved in the apical chloride secretion indicating that TMEM16A could be addressed for the treatment of chloride secretion defects like in Cystic- Fibrosis (CF). In this paper we generated knockout cell lines using CRISPR/Cas9-mediated ablation in a healthy human iPSC line (MHHi001-A), in a CF patient iPSC line (MHHi002-A) and in its corrected counterpart (MHHi002-A-1). These lines can be used for gaining information about the role of TMEM16A for mucus secretion and/or production and evaluating its therapeutic potential.