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Backgrounds: Compared to proton pump inhibitors, vonoprazan exerts a greater inhibitory effect on gastric acid secretion and is useful for treating acid-related diseases, such as gastro-esophageal reflux disease. However, there is a problem that vonoprazan causes hypergastrinemia, which confers a risk of carcinoid tumor. A previous report demonstrated that pirenzepine, an M1 muscarinic receptor antagonist, enhances the acid inhibitory effects while suppressing hypergastrinemia induced by omeprazole. Here, we examined whether pirenzepine enhances the gastric acid inhibitory effects of vonoprazan without further increasing serum gastrin levels.Methods: Eleven healthy volunteers were subjected to 24-hour intragastric pH monitoring and serum gastrin measurements on day 7 of three different regimens: pirenzepine 75mg alone, vonoprazan 10mg alone, and vonoprazan 10mg plus pirenzepine 75mg administered in a randomized crossover fashion.Results: Median pH 4 holding time ratios (range) achieved with pirenzepine 75mg, vonoprazan 10mg and vonoprazan 10mg plus pirenzepine 75mg were 6.9% (2.4–32.8%), 88.4% (54.6–100%), and 84.2% (40.3–100%), respectively. Respective serum gastrin levels were 79 (75–210) pg/ml, 310 (110–870) pg/ml, and 170 (140–930) pg/ml. In cases with hypergastrinemia (gastrin≥200pg/ml) induced by vonoprazan 10mg alone, concomitant treatment with pirenzepine significantly reduced serum gastrin levels from 370pg/ml to 180pg/ml (P=0.028).Conclusion: Although pirenzepine does not enhance acid inhibition, it does improve hypergastrinemia induced by vonoprazan to some extent.

Suzuki et al. reported that the VA-Dual therapy was better at eradicating the clarithromycin-resistant strains of H. pylori than the VAC-Triple therapy. We infer that pharmacodynamic antagonism between clarithromycin and amoxicillin underly this phenomenon.

Manganese (Mn) homeostasis involves coordinated regulation of specific proteins involved in Mn influx and efflux. However, the proteins that are involved in detoxification/efflux have not been completely resolved, nor has the basis by which they select their metal substrate. Here, we compared six proteins, which were reported to be involved in Mn detoxification/efflux, by evaluating their ability to reduce Mn toxicity in chicken DT40 cells, finding that human ZnT10 (hZnT10) was the most significant contributor. A domain swapping and substitution analysis between hZnT10 and a zinc-specific transporter hZnT1 showed that residue N43, which corresponds to the His residue constituting the potential intramembranous zinc coordination site in other ZnT transporters, is necessary to impart hZnT10's unique Mn mobilization activity; residues C52 and L242 in transmembrane domains II and V play a subtler role in controlling the metal specificity of hZnT10. Interestingly, the H->N reversion mutant in hZnT1 conferred Mn transport activity and loss of zinc transport activity. These results provide important information about Mn detoxification/efflux mechanisms in vertebrate cells as well as the molecular characterization of hZnT10 as a Mn transporter.

Aceruloplasminemia is an autosomal recessive disorder of iron metabolism resulting from mutations of the ceruloplasmin gene. To better define the neurological phenotype of aceruloplasminemia we reviewed reports of published cases and sought details of unpublished ones. We identified 32 published reports and 1 unpublished case. The age at diagnosis ranged from 16 to 71 years with a mean of 51. For the 28 homozygous cases the most common presentation was with cognitive impairment (12/28, 42%) accompanied by craniofacial dyskinesia (8/28, 28%), cerebellar ataxia (13/28, 46%) and retinal degeneration (21/28, 75%). Four heterozygotes presented with cerebellar signs or tremor, whilst 1 had chorea-athetosis. There were no genotype-phenotype associations, but homozygotes tended to have severer disease., Journal Article, Review, info:eu-repo/semantics/published

Aceruloplasminemia is an autosomal recessive disorder of iron metabolism resulting from mutations of the ceruloplasmin gene. To better define the neurological phenotype of aceruloplasminemia we reviewed reports of published cases and sought details of unpublished ones. We identified 32 published reports and 1 unpublished case. The age at diagnosis ranged from 16 to 71 years with a mean of 51. For the 28 homozygous cases the most common presentation was with cognitive impairment (12/28, 42%) accompanied by craniofacial dyskinesia (8/28, 28%), cerebellar ataxia (13/28, 46%) and retinal degeneration (21/28, 75%). Four heterozygotes presented with cerebellar signs or tremor, whilst 1 had chorea-athetosis. There were no genotype-phenotype associations, but homozygotes tended to have severer disease., Journal Article, Review, info:eu-repo/semantics/published

Aceruloplasminemia is an autosomal recessive neurodegenerative disease characterized by iron accumulation in the brain as well as visceral organs. It is a loss-of-function disorder caused by mutations in the ceruloplasmin gene. Clinically, this disease consists of the triad of adult-onset neurological disease, retinal degeneration and diabetes mellitus. Massive iron accumulation and extensive loss of neurons are observed in the basal ganglia. The elevated iron concentration is associated with increased lipid peroxidation in the brains of aceruloplasminemia patients. Enlarged or deformed astrocytes and spheroid-like globular structures are characteristic neuropathological findings in aceruloplasminemia. Moreover, deformed astrocytes and globular structures react positively to anti-4-hydroxynonenal antibody, suggesting that increased oxidative stress is involved in neuronal cell death in aceruloplasminemia brain. More than 30 aceruloplasminemia-causing mutations in the ceruloplasmin gene have been identified. We examined the biosynthesis of two missense ceruloplasmin proteins that result from a Japanese P177R mutation and a Dutch G631R mutation, using Chinese hamster ovary cell expression system. The P177R mutant protein is retained in the endoplasmic reticulum. The G631R mutant protein, predicted to alter the interactions at a single type I copper-binding site, prevented incorporation of copper into apoceruloplasmin and resulted in the synthesis and secretion only of apoceruloplasmin. Molecular analysis of missense mutations showed different structure-function relationships in ceruloplasmin protein. The investigation of mutant ceruloplasmin reveals new insights into molecular pathogenesis of aceruloplasminemia as well as biosynthesis, trafficking, and function of ceruloplasmin.