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Zhou Saijun, Li Xin, Wang Jie, Xiao Shumin, Liu Shuaihui, Yu Pei
VEGF-NO axis uncoupling is an important pathogenesis for DN. Reduced β 2GPI could play a part in VEGF signaling pathway and has a protective effect on diabetic vascular disease. This study investigates the effect of reduced β 2GPI on glomerular mesangial cells VEGF-NO axis uncoupling induced by high glucose. Compared to control group, glomerular mesangial cell line HBZY-1 cells treated with high glucose expressed higher levels of VEGF mRNA and protein and produced more ROS but less NO. The related proteins related to VEGF-NO axis were assayed...
2018: BioMed Research International
Dawn Cordeiro, Garrett Bullivant, Ronald D Cohn, Julian Raiman, Saadet Mercimek-Andrews
We report the outcome of 12 patients with inherited neurotransmitter disorders of monoamine, tetrahydrobiopterin and γ amino butyric acid metabolisms from a single Inherited Neurotransmitter Disorder Clinic including tyrosine hydroxylase (n=2), aromatic l-amino acid decarboxylase (n=1), 6-pyruvoyltetrahydropterin synthase, dihydropteridine reductase and succinic semialdehyde dehydrogenase deficiencies. Six patients (with 6-pyruvoyltetrahydropterin synthase, dihydropteridine reductase and tyrosine hydroxylase deficiencies) had normal neurodevelopmental outcome on treatment...
August 15, 2018: Canadian Journal of Neurological Sciences. le Journal Canadien des Sciences Neurologiques
Jingyuan Li, Shangming Liu, Guangqing Cao, Yuanyuan Sun, Weiqian Chen, Fajin Dong, Jinfeng Xu, Cheng Zhang, Wencheng Zhang
Smoking is a major preventable risk factor for atherosclerosis. However, the causative link between cigarette smoke and atherosclerosis remains to be established. The objective of this study is to characterize the role of GTP cyclohydrolase 1 (GTPCH1), the rate-limiting enzyme for de novo tetrahydrobiopterin (BH4) synthesis, in the smoking-accelerated atherosclerosis and the mechanism involved. In vitro, human umbilical vein endothelial cells were treated with nicotine, a major component of cigarette smoke, which reduced the mRNA and protein levels of GTPCH1 and led to endothelial dysfunction...
August 9, 2018: Journal of Cellular and Molecular Medicine
Zhiqi Tang, Lijuan Liu, Yujie Guo, Guoxiong Deng, Meixiang Chen, Jinru Wei
The present study examined whether exendin‑4 (Ex4) can improve the endothelial dysfunction of apolipoprotein E knockout (APOE‑KO) mice fed a high‑cholesterol diet and the potential mechanism by which it acts. Genetically wild‑type (WT) C57BL/6 mice and APOE‑KO mice of C57BL/6 background, were each randomly assigned to receive either Ex4 treatment (Ex4‑treated, for 8 weeks) or not (control). The 4 groups were fed the same high‑cholesterol diet for 8 weeks. The following were measured at the end of the eighth week: Endothelium‑dependent vasodilation of the arteries; plasma nitric oxide (NO) and metabolic index; levels of endothelial NO synthase (eNOS); phosphorylated eNOS (p‑eNOS; Ser‑1,177); guanosine triphosphate cyclohydrolase‑1 (GCH1); and tetrahydrobiopterin (THB)...
August 1, 2018: Molecular Medicine Reports
Muhammad Wasim, Fazli Rabbi Awan, Haq Nawaz Khan, Hina Ayesha
Phenylketonuria (PKU) is an autosomal recessive disorder caused by the deficiency of phenylalanine hydroxylase enzyme that catalyzes the conversion of L-phenylalanine to L-tyrosine using tetrahydrobiopterin (BH4) as a cofactor. Among aminoacidopathies, PKU is one of the most prevalent disorders in different populations. It may be caused by deficiency of BH4 or mutations in PAH. About 98% of PKU patients have mutations in the PAH, while the remaining have BH4 deficiency. If PKU is diagnosed earlier in life using advance analytical techniques (e...
2018: Critical Reviews in Eukaryotic Gene Expression
S LaCorte
It is thought that an ill defined biochemical cascade may lead to protracted withdrawal symptoms subsequent to discontinuance of routine use of benzodiazepine class drugs and establish chronic illness in some patients. In this review, published findings are presented that support the novel concept that withdrawal from benzodiazepine class drugs can trigger elevated and sustained levels of a potent oxidant called peroxynitrite via potentiation of the L-type voltage-gated calcium channels, and in the later stages of withdrawal, via excessive N-methyl-D-aspartate receptor activity, as well...
September 2018: Medical Hypotheses
Yanhua Qin, Weiming Hu, Yang Yang, Zhiying Hu, Weiyun Li, Marong Fang
Aberrant production of nitric oxide following inducible nitric oxide synthase (iNOS) expression has been implicated in cell death and contributes to ischemic brain injury. Tetrahydrobiopterin (BH4) is an essential cofactor of NOS activity. Herein, we evaluated antiapoptotic and anti-inflammatory effects of diamino-6-hydroxypyrimidine (DAHP), a guanosine 5'-triphosphate cyclohydrolase 1 (GTPCH1) inhibitor on focal cerebral ischemia-reperfusion injury by middle cerebral artery occlusion and reperfusion (MCAO) and investigated the underlying mechanism...
2018: Behavioural Neurology
Stephan C J Huijbregts, Annet M Bosch, Quirine A Simons, Rianne Jahja, Martijn C G J Brouwers, Leo M J De Sonneville, Maaike C De Vries, Floris C Hofstede, Carla E M Hollak, Mirian C H Janssen, Janneke G Langendonk, M Estela Rubio-Gozalbo, Jaap J Van der Meere, Ans T Van der Ploeg, Francjan J Van Spronsen
The aim of this study was to examine Health-Related Quality of Life (HRQoL) of patients with Phenylketonuria (PKU) in three different age groups and to investigate the impact of metabolic control and tetrahydrobiopterin (BH4) treatment on HRQoL of these patients. Participants were 90 early-treated patients aged 7 to 40 years (M = 21.0, SD = 10.1) and 109 controls aged 7 to 40.8 years (M = 19.4, SD = 8.6). HRQoL was assessed with the (generic) TNO-AZL questionnaires. Overall, good HRQoL was reported for children below 12 years of age, although they were judged to be less autonomic than their healthy counterparts...
July 7, 2018: Molecular Genetics and Metabolism
Nana Li, Ping Yu, Bin Rao, Ying Deng, Yixiong Guo, Yushan Huang, Lijie Ding, Jun Zhu, Huanming Yang, Jian Wang, Jian Guo, Fang Chen, Zhen Liu
Background The overall incidence of hyperphenylalaninemia (HPA) in China is 1:11,763, with tetrahydrobiopterin (BH4) deficiency accounting for 8.55% of patients with HPA in the mainland. Much progress has been made in the diagnosis and treatment of BH4 deficiency with the introduction of neonatal screening in China. However, the screening rate is still low and screening is not universally available. Methods A total of 44 BH4-deficient patients were enrolled in this study, of which 39 were diagnosed with BH4 deficiency, while the remaining five showed typical characteristics of BH4 deficiency at a later period...
July 12, 2018: Journal of Pediatric Endocrinology & Metabolism: JPEM
Sven F Garbade, Nan Shen, Nastassja Himmelreich, Dorothea Haas, Friedrich K Trefz, Georg F Hoffmann, Peter Burgard, Nenad Blau
PURPOSE: The nature of phenylalanine hydroxylase (PAH) variants determines residual enzyme activity, which modifies the clinical phenotype in phenylketonuria (PKU). We exploited the statistical power of a large genotype database to determine the relationship between genotype and phenotype in PKU. METHODS: A total of 9336 PKU patients with 2589 different genotypes, carrying 588 variants, were investigated using an allelic phenotype value (APV) algorithm. RESULTS: We identified 251 0-variants encoding inactive PAH, and assigned APVs (0 = classic PKU; 5 = mild PKU; 10 = mild hyperphenylalaninaemia) to 88 variants in PAH-functional hemizygous patients...
July 12, 2018: Genetics in Medicine: Official Journal of the American College of Medical Genetics
Toshiharu Nagatsu, Akira Nakashima, Hiroshi Ichinose, Kazuto Kobayashi
Parkinson's disease (PD) is an aging-related movement disorder mainly caused by a deficiency of neurotransmitter dopamine (DA) in the striatum of the brain and is considered to be due to progressive degeneration of nigro-striatal DA neurons. Most PD is sporadic without family history (sPD), and there are only a few percent of cases of young-onset familial PD (fPD, PARKs) with the chromosomal locations and the genes identified. Tyrosine hydroxylase (TH), tetrahydrobiopterin (BH4)-dependent and iron-containing monooxygenase, catalyzes the conversion of L-tyrosine to L-3,4-dihydroxyphenylalanine (L-DOPA), which is the initial and rate-limiting step in the biosynthesis of catecholamines (DA, noradrenaline, and adrenaline)...
July 11, 2018: Journal of Neural Transmission
Michael Horn, Karin Nienhaus, G Ulrich Nienhaus
Nitric oxide synthases (NOSs) are heme enzymes that generate highly reactive nitric oxide from l-arginine (l-Arg) in a complex mechanism that is still only partially understood. We have studied carbon monoxide (CO) binding to the oxygenase domain of murine inducible NOS (iNOS) by using flash photolysis. The P420 and P450 forms of the enzyme, assigned to a protonated and unprotonated proximal cysteine, through which the heme is anchored to the protein, show markedly different CO rebinding properties. The data suggest that P420 has a widely open distal pocket that admits water...
July 18, 2018: Journal of Physical Chemistry. B
Lamia Heikal, Anna Starr, Dania Hussein, Jesus Prieto-Lloret, Phil Aaronson, Lea Ann Dailey, Manasi Nandi
Reduced nitric oxide (NO) bioavailability correlates with impaired cardiovascular function. NO is extremely labile and has been challenging to develop as a therapeutic agent. However, NO bioavailability could be enhanced by pharmacologically targeting endogenous NO regulatory pathways. Tetrahydrobiopterin, an essential cofactor for NO production, is synthesized by GTP cyclohydrolase-1 (GCH1), which complexes with GCH1 feedback regulatory protein (GFRP). The dietary amino acid l-phenylalanine activates this complex, elevating vascular BH4 ...
June 2018: JACC. Basic to Translational Science
María L Couce, Paula Sánchez-Pintos, Isidro Vitoria, María-José De Castro, Luís Aldámiz-Echevarría, Patricia Correcher, Ana Fernández-Marmiesse, Iria Roca, Alvaro Hermida, Miguel Martínez-Olmos, Rosaura Leis
BACKGROUND: In patients with phenylketonuria (PKU), a low-phenylalanine (Phe) diet supplemented with low-protein foods and a Phe-free amino acid mixture favors a dietary intake rich in carbohydrates, but little is known about how these molecules are metabolized in this setting. The objective of the present study was to analyze carbohydrate metabolism in patients with hyperphenylalaninemia. METHODS: We conducted a multicenter cross-sectional study to investigate biochemical markers of basal and postprandial carbohydrate metabolism in PKU patients according to age, Phe tolerance, waist circumference and body mass index (BMI), diet, tetrahydrobiopterin (BH4) supplementation, and adherence to treatment...
June 27, 2018: Orphanet Journal of Rare Diseases
Alexandra Latini, Lucila de Bortoli da Silva, Débora da Luz Scheffer, Ananda Christina Staats Pires, Filipe José de Matos, Renata T Nesi, Karina Ghisoni, Roberta de Paula Martins, Paulo Alexandre de Oliveira, Rui D Prediger, Marisa Ghersi, Laura Gabach, Mariela Fernanda Pérez, Susana Rubiales-Barioglio, Rita Raisman-Vozari, Raymond Mongeau, Laurence Lanfumey, Aderbal Silva Aguiar
Tetrahydrobiopterin (BH4) is synthesized by the combined action of three metabolic pathways, namely de novo synthesis, recycling, and salvage pathways. The best-known function of BH4 is its mandatory action as a natural cofactor of the aromatic amino acid hydroxylases and nitric oxide synthases. Thus, BH4 is essential for the synthesis of nitric oxide, a retrograde neurotransmitter involved in learning and memory. We investigated the effect of BH4 (4-4000 pmol) intracerebroventricular administration on aversive memory, and on BH4 metabolism in the hippocampus of rodents...
June 11, 2018: Molecular Genetics and Metabolism
Haijiao Wang, Wenqian Liu, Feng Shi, Lei Huang, Jiazhang Lian, Liang Qu, Jin Cai, Zhinan Xu
Cellular metabolic networks should be carefully balanced using metabolic engineering to produce the desired products at the industrial scale. As the precursor for the biosynthesis of the neurotransmitter serotonin, 5-hydroxytryptophan (5-HTP) is effective in treating a variety of diseases, such as depression, fibromyalgia, obesity, and cerebellar ataxia. Due to the lack of an efficient synthetic method, commercial production of 5-HTP is only achieved by extracting from the seeds of Griffonia Smplicifolia. This study reports efficient microbial production of 5-HTP via metabolically engineered Escherichia coli...
July 2018: Metabolic Engineering
Arafat Nasser, Lisbeth Birk Møller
Background A great proportion of the variation in pain experience and chronicity is caused by heritable factors. Within the last decades several candidate genes have been discovered either increasing or decreasing pain sensitivity or the risk of chronic pain in humans. One of the most studied genes is the GCH1 gene coding for the enzyme GTP cyclohydrolase 1 (GCH1). GCH1 catalyses the initial and rate-limiting step in the biosynthesis of tetrahydrobiopterin (BH4). The main function of BH4 is regulation of monoamine and nitric oxide biosynthesis, all involved in nociceptive signalling...
April 1, 2014: Scandinavian Journal of Pain
Torsten Gordh
No abstract text is available yet for this article.
April 1, 2014: Scandinavian Journal of Pain
Xiaoyan Dong, Yunpeng Liu, Guishan Zhang, Dandan Wang, Xuan Zhou, Jiahui Shao, Qirong Shen, Ruifu Zhang
Nitric oxide (NO) is an important gas signal that regulates many biological processes, and due to the high nitrogen recycling activity in the rhizosphere, NO is an important signaling molecule in this region. Thus, an understanding of the effect of NO on the rhizomicrobiome, especially on plant beneficial rhizobacteria, is important for the use of these bacteria in agriculture. In this study, the effect of exogenous NO on the beneficial rhizobacterium Bacillus amyloliquefaciens SQR9 was investigated. The results showed that low concentrations of NO increased the ability of the strain SQR9 to form biofilms, while high concentrations of NO inhibited the growth of this bacterium...
June 16, 2018: Biochemical and Biophysical Research Communications
Yinglu Liu, Zhao Dong, Shengyuan Yu
Phenylketonuria (PKU) is a prevalent inherited metabolic disorder caused by a phenylalanine hydroxylase (PAH) or tetrahydrobiopterin (BH4) deficiency, which leads to the accumulation of phenylalanine (PHE). High blood levels of PHE have a toxic effect on the brain and are associated with several neurological signs. Most cases of PKU are identified during infancy, and diagnosis of PKU in adult is rare. Here, we describe a 29-year-old patient with progressive dementia and muscular weakness mimicking X-linked adrenoleukodystrophy...
August 2018: Clinical Neurology and Neurosurgery
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