Mucopolysaccharidosis IVA: screening and identification of mutations of the N-acetylgalactosamine-6-sulfate sulfatase gene

Mutations causing mucopolysaccharidosis IVA in 15 Japanese andone Caucasian patient were characterized. To screen these mutations,we used a combination of single strand conformation polymorphismanalysis and heteroduplex analysis for PCR products of targetedcDNA or genomic DNA. Various small mutations were identifiedin 23 of 26 alleles, while the other six alleles had large rearrangements.Cycle sequencing of PCR products revealed 15 different mutations,including 12 missense, one nonsense, one frame shift (2 bp deletion)and one splice site mutation, in accord with the broad rangeof clinical phenotypes. Two alleles have different mutationsin the same nucleotide position of exon 3 (R94C, CGC     

Effects of whole deletion of CYP2A6 on nicotine metabolism in humans

We investigated the effects of CYP2A6 genotypes on nicotine metabolism, focused from nicotine to cotinine and its additional 3'-hydroxylating resulted in trans-3'-hydroxycotinine formation. In the subjects genotyped by PCR-RFLP method, one cigarette smoking experiment was performed and urine samples were collected for 24 h. In all subjects who smoked, we detected nicotine, cotinine and trans-3'-hydroxycotinine in urine by GC-MS analysis. In whole deletion of CYP2A6, urinary excretion amounts of cotinine and trans-3'-hydroxycotinine were significantly smaller than those in the wild-type of CYP2A6*1. A lack of CYP2A6 reduces the formation of cotinine and trans-3'-hydroxycotinine, but not entirely reduces the trans-3'-hydroxycotinine formation. Unknown cotinine 3'-hydroxylating activity except CYP2A6 are suspected in humans.     

Intestinal alkaline phosphatase is a gut mucosal defense factor maintained by enteral nutrition

Under conditions of starvation and disease, the gut barrier becomes impaired, and trophic feeding to prevent gut mucosal atrophy has become a standard treatment of critically ill patients. However, the mechanisms responsible for the beneficial effects of enteral nutrition have remained a mystery. Using in vitro and in vivo models, we demonstrate that the brush-border enzyme, intestinal alkaline phosphatase (IAP), has the ability to detoxify lipopolysaccharide and prevent bacterial invasion across the gut mucosal barrier. IAP expression and function are lost with starvation and maintained by enteral feeding. It is likely that the IAP silencing that occurs during starvation is a key component of the gut mucosal barrier dysfunction seen in critically ill patients.     

Empagliflozin Disrupts a Tnfrsf12a-Mediated Feed Forward Loop That Promotes Left Ventricular Hypertrophy

Cardiovascular Drugs and Therapy - Although the cardioprotective benefits of sodium-glucose cotransporter 2 (SGLT2) inhibitors are now widely appreciated, the mechanisms underlying these benefits...     

Attempted hydrogen–deuterium exchange of the protio-trimethyloxonium dication (CH3)3OH2+, study of methylating ability of (CH3)3O+ in superacids and theoretical investigations

Attempted hydrogen–deuterium exchange of trimethyloxonium ion, (CH₃)₃O⁺ with excess of 1:1 ²HF/SbF₅ superacid at −30°C over a period of 30 days showed no exchange. Theoretical calculations at the MP2/6–31G** level are in accord with the lack of hydrogen–deuterium exchange in the methyl group of the (CH₃)₃O⁺ cation as protonation (protosolvation) prefers the oxygen lone pair of electrons, instead of a C—H bond. Methylation of aromatics with the (CH₃)₃O⁺CF₃SO₃⁻ in CF₃SO₃H and 2CF₃SO₃H:B(O₃SCF₃)₃ was also studied. Whereas in triflic acid no alkylation was observed, in triflatoboric acid, a powerful superacid, alkylation takes place, indicating protolytic activation of the trimethyloxonium ion.     

ACAGT-007a,an anti-cancer compound that modulates ERK MAPK signaling,induces nuclear enrichment of phosphorylated ERK in T3M4 pancreatic cancer cells

The extracellular-signal-regulated-kinase (ERK) signaling pathway is essential for cell proliferation and is frequently deregulated in human tumors such as pancreatic cancers. ACAGT-007a (GT-7), an anti-cancer compound, stimulates ERK phosphorylation, thereby inducing growth inhibition and apoptosis in T3M4 pancreatic cancer cells. However, how GT-7 stimulates ERK phosphorylation and induces apoptosis in ERK-active T3M4 cells remains unclear. To look into the mechanism, we performed a spatiotemporal analysis of ERK phosphorylation mediated by GT-7 in T3M4 cells. The immunoblotting showed that GT-7 stimulates ERK phosphorylation within 1 h, which was more remarkable after 2 h. Importantly, apoptosis induction as evaluated by the cleaved Caspase-3 was observed only after 2-h incubation with GT-7. The immunofluorescence staining revealed the enrichment of phosphorylated ERK (phospho-ERK) in the nucleus upon 1-h incubation with GT-7. Fractionation experiments showed that GT-7 increases phospho-ERK levels in the cytoplasm within 1 h, whereas nuclear phospho-ERK accumulation is observed after 2-h incubation with GT-7. MEK inhibition by U0126 significantly diminishes nuclear phospho-ERK distribution and apoptosis induction stimulated by GT-7. Thus, GT-7 may initiate the induction of ERK phosphorylation in the cytoplasm, which leads to phospho-ERK enrichment in the nucleus. This nuclear phospho-ERK accumulation by GT-7 precedes and may underlie apoptosis induction in T3M4.