Cheng C.-J.,Tri Service General Hospital |
Cheng C.-J.,Graduate Institute of Life Science |
Sung C.-C.,Tri Service General Hospital |
Lin Y.-C.,Tri Service General Hospital |
And 4 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2015
Context: Aldosterone-producing adenoma (APA) has been linked to mutations in the KCNJ5 gene encoding the inward-rectifying potassium (K+) Kir3.4 channel. These mutations abolish the K+ selectivity of Kir3.4 and, consequently, cause sodium (Na+) leak, depolarized membrane potential, and nonsuppressible aldosterone secretion. Objective: Our objective was to investigate KCNJ5 mutations in patients with sporadic APA and the role of endogenous Kir3.4 in human adrenocortical cells. Design: We screened the KCNJ5 gene from the adrenal adenomas of 69 Chinese patients with sporadic APA and functionally characterized novel Kir3.4 mutations. Results: Thirty-seven percent (26 of 69) of our APA patients carried heterozygous somatic mutations in the KCNJ5 gene. Besides the most common G151R and L168R mutations, we identified a previously uncharacterized E145Q mutation and 2 novel mutations (R115W and E246G) in 6 patients. The E145Q mutant conducted a barium-insensitive Na+-leak current. The R115W and E246G mutants preserved barium-sensitive, K+-selective and G+α-activatable Kir3.4 currents, which were α30% and α15% of wild-type current, respectively. Biotinylation assays revealed markedly reduced membrane abundance of R115W and E246G mutants. All Kir3.4 mutants exerted dominantnegative effects on wild-type channels. Kir3.4 protein expression in APAs with the novel KCNJ5 mutation was significantly lower than those in APAs with wild-type KCNJ5 or Na+-leak KCNJ5 mutations. Inhibition of endogenous Kir3.4 by tertiapin-Q significantly depolarized membrane potential and increased CYP11B2 expression in human adrenocortical cells. Conclusion: BesidesNa+-leak mutations, novel KCNJ5 mutations causing a reduction of surface and total abundance of Kir3.4 are also associated with sporadic APA. Basal Kir3.4 current is important to maintaining normal resting membrane potential and suppressing aldosterone synthesis in human adrenocortical cells. © 2015 by the Endocrine Society.
Yang S.-S.,Tri Service General Hospital |
Yang S.-S.,Graduate Institute of Physiology |
Yang S.-S.,Graduate Institute of Life Science |
Lo Y.-F.,Graduate Institute of Life Science |
And 10 more authors.
Journal of the American Society of Nephrology | Year: 2010
Polymorphisms in the gene encoding sterile 20/SPS1-related proline/alanine-rich kinase (SPAK) associate with hypertension susceptibility in humans. SPAK interacts with WNK kinases to regulate the Na+-K +-2Cl- and Na+-Cl- co-transporters [collectively, N(K)CC]. Mutations in WNK1/4 and N(K)CC can cause changes in BP and dyskalemia in humans, but the physiologic role of SPAK in vivo is unknown. We generated and analyzed SPAK-null mice by targeting disruption of exons 9 and 10 of SPAK. Compared with SPAK+/+ littermates, SPAK+/- mice exhibited hypotension without significant electrolyte abnormalities, and SPAK-/- mice not only exhibited hypotension but also recapitulated Gitelman syndrome with hypokalemia, hypomagnesemia, and hypocalciuria. In the kidney tissues of SPAK-/- mice, the expression of total and phosphorylated (p-)NCC was markedly decreased, but that of p-OSR1, total NKCC2, and p-NKCC2 was significantly increased. We observed a blunted response to thiazide but normal response to furosemide in SPAK-/- mice. In aortic tissues, total NKCC1 expression was increased but p-NKCC1 was decreased in SPAK-deficient mice. Both SPAK+/- and SPAK-/- mice had impaired responses to the selective α1-adrenergic agonist phenylephrine and the NKCC1 inhibitor bumetanide, suggesting that impaired aortic contractility may contribute to the hypotension of SPAK-null mice. In summary, SPAK-null mice have defects of NCC in the kidneys and NKCC1 in the blood vessels, leading to hypotension through renal salt wasting and vasodilation. SPAK may be a promising target for antihypertensive therapy. Copyright © 2010 by the American Society of Nephrology.
Huang L.-Y.,National Health Research Institute |
Wahlqvist M.L.,National Health Research Institute |
Wahlqvist M.L.,Graduate Institute of Life science |
Wahlqvist M.L.,Monash University |
And 4 more authors.
Journal of the American College of Nutrition | Year: 2014
Objective: Dairy foods help achieve essential nutrient adequacy. This role may be conflicted where so-called chronic diseases prevail. We have examined associations between dairy intake and mortality where dairy foods have not been traditional.Methods: A representative Taiwanese cohort of 3810 subjects, aged 19–64 years, derived from the Nutrition and Health Survey in Taiwan (NAHSIT, 1993–1996) was linked to death registration (1993–2008). Participants were categorized by 4 dairy weekly intake frequencies from 0 to >7 times. Mortality hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using Cox proportional-hazards models.Results: Nonconsumers of dairy products included 30.7% of the men and 22.1% of the women. Adverse sociodemographic and personal behaviors were generally significantly associated with lower dairy consumption. After adjustment for covariates, together with body mass index (BMI) and supplement use, those with 3–7 times/week intakes had an HR (95% CI) for all-cause mortality of 0.61 (0.39–0.96) with a significant dose–response trend (p = 0.043). Similarly, the HR for cardiovascular disease (CVD) mortality with dairy weekly intake frequency >7 was 0.14 (0.02–0.97) with a significant linear trend (p = 0.007). For stroke, the corresponding HR (95% CI) was 0.03 (0.00–0.28) with a linear trend. By age and with adjustment for dietary quality, food, and calcium or vitamin D intake, significance and dose–response relationships remained. Dairy intake and cancer mortality were not associated.Conclusion: In a Chinese food culture, a dairy foods intake in adults up to 7 times a week does not increase mortality and may have favorable effects on stroke. © 2014, © American College of Nutrition.
Chang Y.-C.,Graduate Institute of Life science |
Nieh S.,Tri Service General Hospital |
Chen S.-F.,China Medical University at Heping |
Jao S.-W.,Tri Service General Hospital |
And 2 more authors.
Histopathology | Year: 2010
Aims: To test the validity of an invasive pattern grading score (IPGS) developed for oral squamous cell carcinoma (OSCC) as a prognostic indicator and to elucidate the relationship between the IPGS and clinical parameters. Methods and results: The IPGS was applied to a total of 153 cases of OSCC. There were significant correlations between IPGS and distant metastasis (P = 0.01) or recurrence (P = 0.001). However, there were no significant correlations between IPGS and gender, age, size or extent, location, status of lymph node metastasis, clinical staging, or histological grading. Cases of OSCC with higher IPGS were associated with poor patient survival (P < 0.001) and higher probability of tumour recurrence (P = 0.001). Intraobserver ( = 0.74) and interobserver agreement ( = 0.67) were very satisfactory. Conclusions: Our study confirms the validity of the IPGS, an indicator that is simple and easy to use. IPGS not only provides histological assessment of biological behaviour, but also offers an independent prognostic factor that may influence the treatment of OSCC. © 2010 Blackwell Publishing Limited.
Tang S.-H.,Tri Service General Hospital |
Huang H.-S.,Taipei Medical University |
Wu H.-U.,Graduate Institute of Life science |
Chuang M.-J.,Tri Service General Hospital |
And 8 more authors.
Oncotarget | Year: 2014
The polycomb group gene, EZH2, is highly expressed in advanced bladder cancer. Here we demonstrated that down-regulation of EZH2 in tumor tissues after neoadjuvant chemotherapy correlated with good therapeutic response in advanced bladder cancer. We next developed a small molecule, NSC745885, derived from natural anthraquinone emodin, which down-regulated EZH2 via proteasome-mediated degradation. NSC745885 showed potent selective toxicity against multiple cancer cell lines but not normal cells. NSC745885 treatment overcame multiple-drug resistance and inhibited growth of resistant cancer cells. Over-expression of EZH2 in cancer cells attenuated effects of NSC745885, suggesting that down-regulation of EZH2 was responsible for growth inhibition of NSC745885. NSC745885 also suppressed tumor growth and down-regulated EZH2 in vivo. These results indicate that NSC7455889 suppresses bladder cancer by targeting EZH2.
Chien W.-C.,National Defense Medical Center |
Chung C.-H.,Graduate Institute of Life science |
Lai C.-H.,National Defense Medical Center |
Chou C.-H.,National Defense Medical Center
International Journal of Injury Control and Safety Promotion | Year: 2014
The aim of the article was to investigate the injury types and medical utilisations among patients more than 65 years in Taiwan. The data used in this study were obtained from the years 1997 to 2008 of the National Health Insurance Research Database (NHIRD). The patients with the age of 65 years and older as well as with ICM-9-CM discharge injury principal diagnoses 800-959 were included in this study. SPSS 18.0 was used for data analysis. The results showed that there were 518,601 older adults hospitalised because of injuries in the period of study. The average age among them was 76.1 years old and 51.7% of them were females. The common causes of injury were falls and motor vehicle accident. The average number of operations that patients received was one, and the average length of stay was 9.1 days. The total medical expenditure was over NT$ 28.9 billion, and the average expenditure was NT$ 55,738. The factors associated with deaths were sex, ages, co-morbidity disease, level of care, number of operations, length of stay, expenditure of medical care, injury types and causes of injury. This study concludes that in order to decrease the incident of injuries in elder patients, the education of preventing falls and traffic safety should be promoted continuously among elders. © 2014 Copyright Taylor & Francis Group, LLC.
Shih T.-Y.,A-Life Medical |
Young T.-H.,Cardinal Tien Hospital |
Lee H.-S.,Tri Service General Hospital |
Hsieh C.-B.,Tri Service General Hospital |
Hu O.Y.-P.,Graduate Institute of Life science
AAPS Journal | Year: 2013
Isoniazid (INH) and rifampicin (RIF) are the first-line drugs for antituberculosis (anti-TB) chemotherapy. The levels of serum transaminases [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)] are abnormal in 27% of patients undergoing INH and RIF treatments and in 19% of patients undergoing treatment with INH alone. Cytochrome P450 2E1 (CYP2E1) metabolizes many toxic substrates, including ethanol, carbon tetrachloride, and INH, which ultimately results in liver injury. The objective of this study was to screen for CYP2E1 inhibitors in vitro and investigate whether the selected compound could prevent INH/RIF-induced hepatotoxicity in vivo. We screened 83 known compounds from food and herbal medicines as inhibitors of CYP2E1. The hepatotoxic dose of INH/RIF was 50/100 mg kg-1 day-1. Hepatotoxicity was assessed using galactose single-point (GSP) method (a quantitative measurement of liver function), histopathological examination of the liver, malondialdehyde (MDA) assay, and measurement of AST and ALT activities. Kaempferol inhibited CYP2E1 activity in mice by 0.31- to 0.48-fold (p < 0.005). Mice with INH/RIF-induced hepatotoxicity showed significantly abnormal serum levels of AST and ALT, and GSP value, and these values could be decreased by the administration of kaempferol (p < 0.005). Kaempferol significantly reduced the depletion of hepatic glutathione and prevented the increase in MDA formation in mice. Furthermore, kaempferol did not affect the anti-TB effects of INH/RIF. To our knowledge, this is the first report of kaempferol's utility as an adjuvant for preventing CYP2E1-mediated hepatotoxicity induced by drugs such as INH and RIF. © 2013 American Association of Pharmaceutical Scientists.
PubMed | Graduate Institute of Life science, National Defense Medical Center and National Chung Hsing University
Type: Journal Article | Journal: Archives of toxicology | Year: 2016
Tubular cell apoptosis significantly contributes to cisplatin-induced acute kidney injury (AKI) pathogenesis. Although KCa3.1, a calcium-activated potassium channel, participates in apoptosis, its involvement in cisplatin-induced AKI is unknown. Here, we found that cisplatin treatment triggered an early induction of KCa3.1 expression associated with HK-2 cell apoptosis, the development of renal tubular damage, and apoptosis in mice. Treatment with the highly selective KCa3.1 blocker TRAM-34 suppressed cisplatin-induced HK-2 cell apoptosis. We further assessed whether KCa3.1 mediated cisplatin-induced AKI in genetic knockout and pharmacological blockade mouse models. KCa3.1 deficiency reduced renal function loss, renal tubular damage, and the induction of the apoptotic marker caspase-3 in the kidneys of cisplatin-treated KCa3.1 (-/-) mice. Pharmacological blockade of KCa3.1 by TRAM-34 similarly attenuated cisplatin-induced AKI in mice. Furthermore, we dissected the mechanisms underlying cisplatin-induced apoptosis reduction via KCa3.1 blockade. We found that KCa3.1 blockade attenuated cytochrome c release and the increase in the intrinsic apoptotic mediators Bax, Bak, and caspase-9 after cisplatin treatment. KCa3.1 blocking inhibited the cisplatin-induced activation of the endoplasmic reticulum (ER) stress mediator caspase-12, which is independent of calcium-dependent protease m-calpain activation. Taken together, KCa3.1 blockade protects against cisplatin-induced AKI through the attenuation of apoptosis by interference with intrinsic apoptotic and ER stress-related mediators, providing a potential target for the prevention of cisplatin-induced AKI.
PubMed | Graduate Institute of Life science and Taipei Veterans General Hospital
Type: | Journal: Stem cell research & therapy | Year: 2016
The characteristics and therapeutic potential of subtypes of mesenchymal stem cells (MSCs) are largely unknown. In this study, CD146(+) and CD146(-) MSCs were separated from human umbilical cords, and their effects on regulatory T cells (Tregs), Th17 cells, chondrogenesis, and osteogenesis were investigated.Flow cytometry was used to quantify IL-6 and TGF-1 expressed on CD146(+) and CD146(-) MSCs. The therapeutic potential of both subpopulations was determined by measuring the clinical score and joint histology after intra-articular (IA) transfer of the cells into mice with collagen-induced arthritis (CIA).Compared with CD146(-) MSCs, CD146(+) MSCs expressed less IL-6 and had a significantly greater effect on chondrogenesis. After T lymphocyte activation, Th17 cells were activated when exposed to CD146(-) cells but not when exposed to CD146(+) cells both in vitro and in vivo. IA injection of CD146(+) MSCs attenuated the progression of CIA. Immunohistochemistry showed that only HLA-A(+) CD146(+) cells were detected in the cartilage of CIA mice. These cells may help preserve proteoglycan expression.This study suggests that CD146(+) cells have greater potency than CD146(-) cells for cartilage protection and can suppress Th17 cell activation. These data suggest a potential therapeutic application for CD146(+) cells in treating inflammatory arthritis.
PubMed | Tri Service General Hospital, Graduate Institute of Life science, A-Life Medical, National Ilan University and Academia Sinica, Taiwan
Type: | Journal: Free radical biology & medicine | Year: 2016
Sterile 20/SPS1-related proline/alanine-rich kinase (SPAK) can stimulate production of proinflammatory cytokines and interact with inflammation-related molecules. However, it has yet to be determined whether SPAK plays a pathophysiological role in the complicated pathological mechanisms of IgA nephropathy (IgAN), which is mainly characterized by mesangial cell (MC) proliferation and is the most common form of glomerulonephritis. In the present study, we examined the pathophysiological role of SPAK in IgAN using a mouse model and cell models. Our results clearly showed that (1) SPAK deficiency prevents the development of IgAN and inhibits production of immune/inflammatory mediators and T cell activation and proliferation; and (2) when primed with IgA immune complexes (IgA IC), both peritoneal macrophages and primary MCs from SPAK knockout mice show markedly reduced production of proinflammatory cytokines and inhibition of NF-B/MAPKs activation. We proposed that activation of SPAK and the NF-B/MAPKs signaling pathway in MCs, macrophages and T cells of the glomerulus may be a mechanism underlying the pathogenesis of IgAN. The activation of SPAK in renal tubuloepithelial cells either directly by IgA IC or an indirect action of the activated MCs or infiltrating mononuclear leukocytes seen in the kidney may further aggravate the disease process of IgAN. Our results suggest that SPAK is a potential therapeutic target for the glomerular disorder.