Design and Pharmacological Chaperone Effects of N-(4'-Phenylbutyl)-DAB Derivatives Targeting the Lipophilic Pocket of Lysosomal Acid α-Glucosidase.

This study provides the first example of a strategy to design a practical ligand toward lysosomal acid α-glucosidase (GAA) focusing on N-alkyl derivatives of 1,4-dideoxy-1,4-imino-d-arabinitol (DAB). The optimized N-4'-(p-trifluoromethylphenyl)butyl-DAB (5g) showed a Ki value of 0.73 µM, which was 353-fold higher affinity than N-butyl-DAB (3f) without a terminal phenyl group. Docking analysis showed that the phenyl part of 5g was accommodated in a lipophilic pocket. Furthermore, the p-trifluoromethyl group effectively suppresses the fluctuation of the phenyl group, allowing it to produce a stable bonding form with GAA. 5g increased the midpoint of the protein's protein denaturation temperature (Tm) by 6.6 °C above that in the absence of the ligand and acted as a "thermodynamic stabilizer" to improve the thermal stability of rhGAA. 5g dose-dependently increased intracellular GAA activities in Pompe patient's fibroblasts with the M519V mutation; its effect was comparable to that of DNJ, which is under clinical trials.

Treatment with Interleukin-25 Suppresses Short-Term High-Fructose Diet-Induced Hepatic Gene Expression and Activities of Fatty Acid Synthesis Enzymes in Rats.

This study aimed to investigate the effects of interleukin-25, which belongs to the interleukin-17 family, on short-term high-fructose diet-induced hepatic triacylglycerol accumulation. Rats were fed a high-starch (control) or high-fructose diet for 7 d, with or without intraperitoneal administration of recombinant interleukin-25 from days 3-7. Treatment with interleukin-25 significantly reduced the mRNA levels and activity of fatty acid synthesis enzymes and caused a nominal reduction in hepatic triacylglycerol levels in rats fed a high-fructose diet but not in those fed a control diet. Interleukin-25 treatment did not affect the mRNA levels of ß-oxidation enzymes in either the control or fructose-fed rats. These results suggest that treatment with interleukin-25 suppresses short-term high-fructose diet-induced fatty acid synthesis and leads to the alleviation of triacylglycerol accumulation in the liver.

Dietary Supplementation with Sodium Butyrate Reduces High-sucrose Diet-induced Hepatic Accumulation of Triacylglycerols and Expression of Fatty Acid Synthesis Enzymes in Rats.

We investigated the effects of dietary supplementation with sodium butyrate (NaB) on the lipid levels, gene expression, and proteins related to lipid metabolism in nonalcoholic fatty liver disease (NAFLD) rat models fed a high-sucrose diet for 3 weeks. Supplementation with 1% and 3% NaB reduced high-sucrose-induced hepatic triacylglycerol levels and expression of genes and proteins related to fatty acid synthesis, such as fatty acid synthase and malic enzyme, in a dose-dependent manner. NaB supplementation did not affect hepatic cholesterol levels or expression of genes related to ß-oxidation. NaB may prevent high-sucrose-induced NAFLD by repressing the fatty acid synthesis pathway.

Characterization of the human zinc finger nfx­1­type containing 1 encoding ZNFX1 gene and its response to 12­O­tetradecanoyl­13­acetate in HL­60 cells.

Human promyelocytic HL­60 cells can be differentiated into macrophage­like cells by treatment with 12­O­tetra decanoylphorbol­13­acetate (TPA). Certain 5' upstream regions of the zinc finger protein (ZNF)­encoding genes contain duplicated GGAA motifs, which are frequently found in the TPA­responding gene promoter regions. To examine transcriptional responses to TPA, 5'flanking regions of human zinc finger CCCH­type containing, antiviral, ZNF252, ZNF343, ZNF555, ZNF782 and zinc finger nfx­1­type containing 1 (ZNFX1) genes were isolated by polymerase chain reaction (PCR) and ligated into a multiple­cloning site of the pGL4.10[luc2] vector. Transient transfection and a luciferase assay revealed that the ZNFX1 promoter most prominently responded to the TPA treatment. Deletion and point mutation experiments indicated that the duplicated GGAA motif in the 100­bp region positively responded to TPA. In addition, reverse transcription­quantitative PCR and western blotting showed that the mRNA and protein of ZNFX1 accumulate during the differentiation of HL­60 cells. These results indicated that expression of the TPA­inducible ZNFX1 gene, which belongs to the group of interferon­responsive genes, is regulated by the cis­action of the duplicated GGAA motif.