Propofol elicits apoptosis and attenuates cell growth in esophageal cancer cell lines.

Propofol is a pharmaceutical agent commonly used as an intravenous anesthetic in surgical treatments and a sedative in intensive care. However, it is largely unknown how exposure to propofol affects the proliferation, invasion, and apoptosis of neoplastic cells in esophageal cancer. In this study, we sought to elucidate the impact of propofol exposure on the growth properties of human esophageal cancer cell lines in vitro. We treated two human esophageal cancer cell lines, KYSE30 and KYSE960, with up to 10 µg/mL of propofol for 12-36 h. The treated cells were then analyzed by cell proliferation assay, Matrigel invasion assay, quantification of caspase-3/7 and -9 activities, and cell staining with Annexin V and 7-aminoactinomycin D to detect early apoptosis and cell death, respectively, via flow cytometry. We found that 3-5 µg/mL propofol reduced the growth and Matrigel invasion of both cell lines in a dose-dependent manner. Executioner caspase-3/7, but not caspase-9 involved in intrinsic apoptosis pathway, was activated by cell exposure to 3-5 µg/mL propofol. In addition, 3-5 µg/mL propofol augmented early apoptosis in both cell lines and increased cell death in the KYSE30 cell line. In summary, exposure to propofol, at concentrations up to 5 µg/mL, led to the reduction of cell growth and Matrigel invasion, as well as the augmentation of apoptosis in esophageal cancer cell lines. These data will help define a methodology to safely utilize propofol, a common general anesthetic and sedative, with esophageal cancer patients.

Efficacy and safety of upadacitinib over 84 weeks in Japanese patients with rheumatoid arthritis (SELECT-SUNRISE).

BACKGROUND: The objective of the study was to evaluate the efficacy and safety of upadacitinib over 84 weeks in Japanese patients with active rheumatoid arthritis (RA) and an inadequate response to conventional synthetic disease-modifying anti-rheumatic drugs. METHODS: All patients completing a 12-week, randomized, double-blind treatment period entered a blinded extension and continued upadacitinib 7.5, 15, or 30 mg once daily (QD), or were switched from placebo to upadacitinib 7.5, 15, or 30 mg QD. Efficacy and safety were assessed over 84 weeks. RESULTS: Of 197 randomized patients, 187 (94.9%) completed the 12-week period and entered the blinded extension; 152 (77.2%) patients were ongoing at week 84. At week 84, the proportions of patients achieving a 20% improvement in American College of Rheumatology criteria (ACR20) were 85.7%, 77.6%, and 58.0% with continued upadacitinib 7.5, 15, and 30 mg, respectively (nonresponder imputation), and were similar in patients who had switched from placebo. Favorable response rates were also observed for more stringent measures of response (ACR50/70) and remission (defined by the Disease Activity Score of 28 joints with C-reactive protein, Clinical Disease Activity Index, or Simplified Disease Activity Index). The 15 mg and 30 mg doses of upadacitinib were associated with more rapid and numerically higher initial responses for some measures of disease activity and remission compared with the 7.5 mg dose. Rates of adverse events, infection, opportunistic infection, serious infection, and herpes zoster were lower with upadacitinib 7.5 and 15 mg versus 30 mg. CONCLUSIONS: Upadacitinib demonstrated sustained efficacy and was well tolerated over 84 weeks in Japanese patients with RA, with upadacitinib 15 mg offering the most favorable benefit-risk profile. TRIAL REGISTRATION: ClinicalTrials.gov NCT02720523 . Registered on March 22, 2016.

Structure and Stereochemistry of Amphidinolide N Congeners from Marine Dinoflagellate Amphidinium Species.

Two highly potent cytotoxic 26-membered macrolides, isocaribenolide-I (1) and a chlorohydrin 2, together with known amphidinolide N (3), have been isolated from a free-swimming dinoflagellate Amphidinium species (KCA09053 and KCA09056 strains) collected off Iriomote Island, Japan. The structures of 1 and 2 were determined to be a congener of 3 with an isobutyl terminus and the chlorohydrin form of 3, respectively, by detailed analyses of spectroscopic data. The relative stereochemistries of 1 and 2 were elucidated by the conformational analyses based on NMR data.

Correction to: Differential effects of sevoflurane on the growth and apoptosis of human cancer cell lines.

The article Differential effects of sevoflurane on the growth and apoptosis of human cancer cell lines, written by Takahiro Hirai, Yuko Konishi, Shoko Mizuno, Zhou Rui, Yao Sun and Kimitoshi Nishiwaki, was originally published electronically on the publisher's internet portal (currently SpringerLink) on 31 October 2019 with open access. With the author(s)' decision to step back from Open Choice, the copyright of the article changed on 5 December 2019 to © Japanese Society of Anesthesiologists 2019 and the article is forthwith distributed under the terms of copyright.

Differential effects of sevoflurane on the growth and apoptosis of human cancer cell lines.

PURPOSE: There have been contradictory findings regarding the effects of sevoflurane on the oncogenic properties of cancer cells. This study was conducted to gain insights into the fundamental rules governing the differential effects of sevoflurane exposure on various cancer cells derived from multiple origins. METHODS: A series of cancer cell lines were exposed to 1% (v/v) sevoflurane for 2-8 h and then assessed for their proliferation, Matrigel invasion, and apoptotic cell death, in comparison with their untreated counterparts. Cell proliferation and Matrigel invasion assays were performed using Coulter counter and Boyden chamber techniques, respectively. Apoptosis was evaluated by staining cells with Annexin V and 7-AAD followed by fluorescence flow cytometry. In addition, the expression of cleaved caspase-3 protein, another marker of apoptosis, was assessed using immunoblotting. RESULTS: Proliferation was significantly enhanced after sevoflurane exposure in six of eight cancer cell lines (NCI-H1299, MDA-MB-231, HCT116, DLD-1, HT29, and RKO). In contrast, sevoflurane attenuated proliferation in the last two cancer cell lines, A549 and MCF-7, as well as in the non-cancerous MCF10A cell line. Cell biological assays using four cancer cell lines demonstrated that accelerated but not attenuated cancer cell proliferation after sevoflurane exposure is associated with enhanced Matrigel invasion and suppressed apoptosis. CONCLUSION: Sevoflurane augmented or hampered cell proliferation and Matrigel invasion depending on the cancer cell line examined. Loss of sevoflurane-induced apoptosis occurring in cancer cell lines is likely to be correlated with their enhanced proliferation after sevoflurane exposure.

Depth-Resolved Characterization of Perylenediimide Side-Chain Polymer Thin Film Structure Using Grazing-Incidence Wide-Angle X-ray Diffraction with Tender X-rays.

Polymers with a perylenediimide (PDI) side chain (PAc12PDI) consist of two kinds of crystalline structures with various types of orientations in a thin film. Understanding the population of the microcrystalline structure and its orientation along the thickness is strongly desired. Grazing-incidence wide-angle X-ray diffraction (GIWAXD) measurements with hard X-rays, which are generally chosen as λ = 0.1 nm, are a powerful tool to evaluate the molecular aggregation structure in thin films. A depth-resolved analysis for the outermost surface of the polymeric materials using conventional GIWAXD measurements, however, has limitations on depth resolution because the X-ray penetration depth dramatically increases above the critical angle. Meanwhile, tender X-rays (λ = 0.5 nm) have the potential advantage that the penetration depth gradually increases above the critical angle, leading to precise characterization for the population of crystallite distribution along the thickness. The population of the microcrystalline states in the PAc12PDI thin film was precisely characterized utilizing GIWAXD measurements using tender X-rays. The outermost surface of the PAc12PDI thin film is occupied by a monoclinic lattice with a = 2.38 nm, b = 0.74 nm, c = 5.98 nm, and ß = 108.13°, while maintaining the c-axis perpendicular to the substrate surface. Additionally, the presence of solid substrate controls the formation of the crystallite with unidirectional orientation.

Preparation of High-Density Polymer Brushes with a Multihelical Structure.

It is well-known that a mixture of isotactic and syndiotactic polymethyl methacrylate (PMMA) forms a stereocomplex consisting of a multihelical structure in which an isotactic chain is surrounded by a syndiotactic chain. Here, we report the basic structure of the stereocomplex formed when the syndiotactic PMMA chains are tethered to a silicon substrate and form a high-density polymer brush. The influence of geometric confinement was investigated by preparing the high-density polymer brushes on a flat and spherical substrate. In both cases, mixing the untethered isotactic PMMA with the grafted syndiotactic PMMA led to the formation of a stereocomplex with a multihelical structure. Static contact angle measurements showed a hindered surface mobility at the outermost surface of the polymer brush, indicating that the stereocomplex forms a crystalline structure. A syndiotactic polymer brush with substituted fluoroalkyl groups was prepared to increase the contrast for grazing incidence wide-angle X-ray diffraction (GIWAXD) measurements. The GIWAXD results verified that the stereocomplex forms a crystalline structure oriented perpendicular to the substrate with a relatively low degree of orientation.

Application of fiber tractography and diffusion tensor imaging to evaluate spinal cord diseases in dogs.

Fiber tractography is a technique capable of depicting the three-dimensional structure and connectivity of nerve fibers using serial magnetic resonance diffusion tensor imaging (DTI). To establish fiber tractography and DTI methods in veterinary clinical medicine, we evaluated fiber tractography and DTI parameters: apparent diffusion coefficient (ADC) values and fractional anisotropy (FA) values, in various spinal cord diseases. Spinal cord DTI was examined in 28 dogs with spinal cord diseases. The ADC and FA values were measured at lesion sites and cranial normal sites on spinal cords, and both values of lesion sites were compared with normal sites. In thoracolumbar intervertebral disk herniation (IVDH) cases, depending on their neurologic grades, fiber tractography indicated rupture of fiber trajectories, loss of neuronal bundles and disorder of fiber directions. In these cases, the average ADC values at lesion sites significantly decreased compared with normal sites (P=0.016). In the progressive myelomalacia case, the average ADC and FA values of hyperintense swollen regions in T2WI decreased compared to both values in other disease cases. Finally, in the meningioma case, the continuity of fiber trajectories improved after the administration of an anticancer agent. This study suggests that fiber tractography and DTI are useful in the diagnosis and prognosis of veterinary spinal cord diseases.

Iriomoteolides-10a and 12a, Cytotoxic Macrolides from Marine Dinoflagellate Amphidinium Species.

Two new macrolides, iriomoteolides-10a (1) and -12a (2), have been isolated from a marine dinoflagellate Amphidinium sp. (KCA09053 strain), and their structures were elucidated on the basis of a detailed two dimensional (2D)-NMR analysis. Compound 1 is a novel 21-membered Amphidinium macrolide, which contains one tetrahydrofuran ring, two ketone carbonyls, two hydroxyl groups, and six one-carbon branches. Compound 2 is a new 12-membered macrolide related to amphidinolide Q. Compound 1 exhibited cytotoxic activity against human cervix adenocarcinoma HeLa and murine hepatocellular carcinoma MH134 cells.

Partial costectomy for tracheal collapse and stenosis associated with perinatal rib fracture in three Japanese Black calves.

2.3-month-old (Case 1), one-month-old (Case 2) and 6-month-old (Case 3), Japanese Black calves presented with mild to severe wheezing. All calves had histories of dystocia at birth with breech presentation. Physical examination, thoracic radiography, endoscopy or computed tomography indicated wheezing associated with tracheal collapse and stenosis caused by perinatal rib fractures. Partial resection of the fractured first and second ribs was performed on all calves. The respiration in Cases 1 and 2 immediately improved after the surgery, while Case 3 required two weeks to improve. Cases 1 and 3 grew up healthy and were sold at auction, but Case 2 had a recurrence of wheezing at three months post-discharge and showed growth retarding. Partial costectomy may be an effective solution for control of respiration, however, further cases are required to discuss the criteria for surgical management and to obtain favorable postoperative prognosis in calves with tracheal collapse and stenosis caused by perinatal rib fractures.

Improved methods of AAV-mediated gene targeting for human cell lines using ribosome-skipping 2A peptide.

The adeno-associated virus (AAV)-based targeting vector has been one of the tools commonly used for genome modification in human cell lines. It allows for relatively efficient gene targeting associated with 1-4-log higher ratios of homologous-to-random integration of targeting vectors (H/R ratios) than plasmid-based targeting vectors, without actively introducing DNA double-strand breaks. In this study, we sought to improve the efficiency of AAV-mediated gene targeting by introducing a 2A-based promoter-trap system into targeting constructs. We generated three distinct AAV-based targeting vectors carrying 2A for promoter trapping, each targeting a GFP-based reporter module incorporated into the genome, PIGA exon 6 or PIGA intron 5. The absolute gene targeting efficiencies and H/R ratios attained using these vectors were assessed in multiple human cell lines and compared with those attained using targeting vectors carrying internal ribosome entry site (IRES) for promoter trapping. We found that the use of 2A for promoter trapping increased absolute gene targeting efficiencies by 3.4-28-fold and H/R ratios by 2-5-fold compared to values obtained with IRES. In CRISPR-Cas9-assisted gene targeting using plasmid-based targeting vectors, the use of 2A did not enhance the H/R ratios but did upregulate the absolute gene targeting efficiencies compared to the use of IRES.

High-resolution 400K oligonucleotide array comparative genomic hybridization analysis of neurofibromatosis type 1-associated cutaneous neurofibromas.

Neurofibromatosis type 1 (NF1) is a genetic disorder where affected individuals develop benign or malignant nervous system tumors. To date, NF1 is caused by mutations in the NF1 tumor suppressor gene located at chromosome band 17q11.2. In this study, we aimed to characterize novel recurrent regional chromosomal imbalances and tumor-related candidate genes in NF1-associated cutaneous neurofibromas. Nine cutaneous neurofibromas from NF1 patients were screened for recurrent chromosomal imbalances using high-resolution 400K oligonucleotide array comparative genomic hybridization (aCGH). All the cases exhibited at least one sub-microscopic abnormality. Regions of recurrent chromosomal imbalances in a least one third of cases were loss of 1q13.2 (33%, FAM19A3), 1q21.1 (44%, RABGAP1L), 2q37.1 (56%, INPP5D), 3p25.1 (67%, CHCHD4), 4p15.32 (56%, FGFBP1), 5q11.2 (56%, ARL15), 6q22.31 (56%, NKAIN2), 6q22.33 (67%, ARHGAP18), 6q25.1 (67%, UST), 7q13 (56%, ADCY1), 12q13.13 (44%, KRT71), 19q13.32 (56%, GRLF1), and 20p11.21 (56%, NLP) and gain of 2p23.3 (76%, C2orf53), 8q22.3 (44%, ODF1) and 8q24.3 (67%, ARC). Several chromosomal imbalances, including loss of 7q11.23, 13q14.1, 14q32.13, 17p12, and 17q11.2 were detected at a lower frequency. We also confirmed that these chromosomal imbalances were not detected in the patient-matched lymphocyte DNAs. Amongst the 6 tumor-related candidate genes (RABGAP1L, ADCY1, SLIT2, GRLF1, UST, and ARC) identified in the regions of recurrent chromosomal imbalances, the gene expression changes of UST (down-regulation) and ARC (up-regulation) were found to be significantly associated with copy number alterations. The novel recurrent chromosomal imbalances and the altered expression levels of the tumor-related candidate genes may be associated with the development of NF1-associated benign cutaneous neurofibromas.

Amphirionin-2, a novel linear polyketide with potent cytotoxic activity from a marine dinoflagellate Amphidinium species.

A novel linear polyketide, amphirionin-2 (1), with two unique hexahydrofuro[3,2-b]furan moieties has been isolated from the cultivated algal cells of a benthic dinoflagellate Amphidinium sp. (strain KCA09051). The structure was elucidated on the basis of detailed analyses of 2D NMR data, and the absolute configuration of C-5 was determined by using modified Mosher's method. Amphirionin-2 (1) exhibited potent cytotoxic activity against human colon carcinoma Caco-2 cells and human lung adenocarcinoma A549 cells.

Amphirionin-4 with potent proliferation-promoting activity on bone marrow stromal cells from a marine dinoflagellate amphidinium species.

A linear polyketide, amphirionin-4 (1), has been isolated from cultivated algal cells of the marine dinoflagellate Amphidinium species. The structure was elucidated on the basis of detailed analyses of 1D and 2D NMR data, and the absolute configurations of C-4 and C-8 were determined using the modified Mosher's method. Amphirionin-4 (1) exhibited extremely potent proliferation-promoting activity on murine bone marrow stromal ST-2 cells (950% promotion) at a concentration of 0.1 ng/mL.

A comparative analysis of constitutive promoters located in adeno-associated viral vectors.

The properties of constitutive promoters within adeno-associated viral (AAV) vectors have not yet been fully characterized. In this study, AAV vectors, in which enhanced GFP expression was directed by one of the six constitutive promoters (human ß-actin, human elongation factor-1α, chicken ß-actin combined with cytomegalovirus early enhancer, cytomegalovirus (CMV), simian virus 40, and herpes simplex virus thymidine kinase), were constructed and introduced into the HCT116, DLD-1, HT-1080, and MCF-10A cell lines. Quantification of GFP signals in infected cells demonstrated that the CMV promoter produced the highest GFP expression in the six promoters and maintained relatively high GFP expression for up to eight weeks after infection of HCT116, DLD-1, and HT-1080. Exogenous human CDKN2A gene expression was also introduced into DLD-1 and MCF-10A in a similar pattern by using AAV vectors bearing the human ß-actin and the CMV promoters. The six constitutive promoters were subsequently placed upstream of the neomycin resistance gene within AAV vectors, and HCT116, DLD-1, and HT-1080 were infected with the resulting vectors. Of the six promoters, the CMV promoter produced the largest number of G418-resistant colonies in all three cell lines. Because AAV vectors have been frequently used as a platform to construct targeting vectors that permit gene editing in human cell lines, we lastly infected the three cell lines with AAV-based targeting vectors against the human PIGA gene in which one of the six promoters regulate the neomycin resistance gene. This assay revealed that the CMV promoter led to the lowest PIGA gene targeting efficiency in the investigated promoters. These results provide a clue to the identification of constitutive promoters suitable to express exogenous genes with AAV vectors, as well as those helpful to conduct efficient gene targeting using AAV-based targeting vectors in human cell lines.

Peridinin from the marine symbiotic dinoflagellate, Symbiodinium sp., regulates eosinophilia in mice.

Peridinin and fucoxanthin, which are natural carotenoids isolated from a symbiotic dinoflagellate, Symbiodinium sp., and a brown alga, Petalonia fascia, respectively, were compared for inhibitory effects on delayed-type hypersensitivity in mice. The number of eosinophils at the site of inflammation and in peripheral blood was compared for the administration of peridinin and fucoxanthin applied by painting and intraperitoneally. Peridinin, but not the structurally-related fucoxanthin, significantly suppressed the number of eosinophils in both the ear lobe and peripheral blood. Furthermore, peridinin applied topically, but not administered intraperitoneally, suppressed the level of eotaxin in the ears of sensitized mice. Fucoxanthin weakly suppressed the concentration of eotaxin in ears only by intraperitoneal administration. Although both carotenoids inhibited the migration of eosinophils toward eotaxin, the inhibitory effect of peridinin was higher than that of fucoxanthin. Peridinin may be a potential agent for suppressing allergic inflammatory responses, such as atopic dermatitis, in which eosinophils play a major role in the increase of inflammation.

Telomere length as a risk factor for hereditary prostate cancer.

BACKGROUND: Telomeres are repetitive nucleotide sequences that stabilize the ends of chromosomes. Critically short telomeres are thought to contribute to cancer development by increasing chromosomal instability. We hypothesized that shorter leukocyte telomere length, a surrogate for inherited prostate cell telomere length, would be associated with increased risk of prostate cancer in hereditary prostate cancer (HPC) families. METHODS: One hundred twelve affected and 63 unaffected men from 28 families were drawn from the Johns Hopkins HPC family database. Relative mean telomere length was measured in isolated peripheral leukocyte DNA by quantitative PCR. Conditional logistic regression was used to estimate the association between quartile of age-adjusted telomere length and prostate cancer. RESULTS: Men in the shortest quartile of telomere length did not have increased odds of prostate cancer compared to men in the other three quartiles (OR = 0.84, 95% CI: 0.32-2.20, P = 0.73). However, when the analysis was restricted to affected men with blood drawn before or within a year of diagnosis (N = 39) and all unaffected men, shorter telomere length was moderately associated with increased odds of prostate cancer (OR = 3.55, 95% CI: 0.82-15.43, P = 0.09). CONCLUSIONS: Though we found no association overall, shorter leukocyte telomere length may be associated with increased odds of prostate cancer when measured in pre-diagnostic samples. Further prospective research is warranted exploring the utility of telomere length as a prostate cancer biomarker.

Arsenic augments the uptake of oxidized LDL by upregulating the expression of lectin-like oxidized LDL receptor in mouse aortic endothelial cells.

Although chronic arsenic exposure is a well-known risk factor for cardiovascular diseases, including atherosclerosis, the molecular mechanism underlying arsenic-induced atherosclerosis remains obscure. Therefore, this study aimed to elucidate this molecular mechanism. We examined changes in the mRNA level of the lectin-like oxidized LDL (oxLDL) receptor (LOX-1) in a mouse aortic endothelial cell line, END-D, after sodium arsenite (SA) treatment. SA treatment significantly upregulated LOX-1 mRNA expression; this finding was also verified at the protein expression level. Flow cytometry and fluorescence microscopy analyses showed that the cellular uptake of fluorescence (Dil)-labeled oxLDL was significantly augmented with SA treatment. In addition, an anti-LOX-1 antibody completely abrogated the augmented uptake of Dil-oxLDL. We observed that SA increased the levels of the phosphorylated forms of nuclear factor of kappa light polypeptide gene enhancer in B cells (NF-κB)/p65. SA-induced upregulation of LOX-1 protein expression was clearly prevented by treatment with an antioxidant, N-acetylcysteine (NAC), or an NF-κB inhibitor, caffeic acid phenethylester (CAPE). Furthermore, SA-augmented uptake of Dil-oxLDL was also prevented by treatment with NAC or CAPE. Taken together, our results indicate that arsenic upregulates LOX-1 expression through the reactive oxygen species-mediated NF-κB signaling pathway, followed by augmented cellular oxLDL uptake, thus highlighting a critical role of the aberrant LOX-1 signaling pathway in the pathogenesis of arsenic-induced atherosclerosis.

Autonomous cure of damaged human intestinal epithelial cells by TLR2 and TLR4-dependent production of IL-22 in response to Spirulina polysaccharides.

In order to analyze the damage of human epithelial cells, we used human quasi-normal FPCK-1-1 cells derived from a colonic polyp in a patient with familial adenomatous polyposis as a monolayer, which is co-cultured with peptidoglycan (PGN)-stimulated THP-1 cells. Co-cultured FPCK-1-1 cells showed a decreased transepithelial electrical resistance (TER) and the lower level of claudin-2. When Spirulina complex polysaccharides were added one day before the start of the co-culture, there was no decrease of TER and claudin-2 (early phase damage). In contrast, when Spirulina complex polysaccharides were added to FPCK-1-1 cells after the level of TER had decreased, there was no recovery at the level of claudin-2, though the TER level recovered (late phase damage). The mucosa reconstitution is suggested to be involved in the recovery from the damaged status. Interestingly, autonomous recovery of FPCK-1-1 cells from both the early and late phase damage requires the production of IL-22, because anti-IL-22 antibodies inhibited recovery in these cases. Antibodies against either TLR2 or TLR4 inhibited the production of IL-22 from FPCK-1-1 colon epithelial cells, suggesting that signals through TLR2 and TLR4 are necessary for autonomous recovery of FPCK-1-1 colon epithelial cells by producing IL-22. In conclusion, we have established a useful model for the study of intestinal damage and recovery using human colon epithelial cells and our data suggest that damage to human colon epithelial cells can, at least in part, be recovered by the autonomous production of IL-22 in response to Spirulina complex polysaccharides.

Arsenic upregulates the expression of angiotensin II Type I receptor in mouse aortic endothelial cells.

Although chronic arsenic exposure is a well-known risk for cardiovascular disease and has a strong correlation with hypertension, the molecular pathogenesis underlying arsenic exposure-induced hypertension remains poorly understood. To delineate the pathogenesis, we examined changes in the mRNA levels of 2 angiotensin II Type I receptor (AT1R) subtypes, AT1AR and AT1BR, in a mouse aortic endothelial cell line, END-D. Quantitative real-time PCR analysis revealed significant increases in the mRNA levels of 2 AT1R subtypes, AT1AR and AT1BR following sodium arsenite (SA) treatment. Flow cytometry analysis revealed that SA increases the generation of reactive oxygen species (ROS) in a dose-dependent manner. In addition, western blot analysis revealed that SA enhances the phosphorylations of c-Jun N-terminal kinases (JNK) and activated protein 1 (AP-1). These phosphorylations were inhibited by N-acetylcysteine (NAC), an anti-oxidant. Finally, SA-induced AT1R expression was found to be prevented both by NAC and specific JNK inhibitor, SP6001325, strongly indicating that AT1R upregulation is a result of the ROS-mediated activation of the JNK signaling pathway. Taken together, our results indicate that arsenic indeed upregulates the AT1R expression, thus highlighting a role of arsenic-induced aberrant AT1R signaling in the pathogenesis of hypertension.