Discovery of pathogenic variants in a large Korean cohort of inherited muscular disorders.

Inherited muscular disorders (IMDs) are clinically and genetically heterogeneous genetic disorders. We investigated the mutational spectrum and genotype-phenotype correlations in Korean patients with IMD. We developed a targeted panel of 69 known IMD genes and recruited a total of 209 Korean patients with IMD. Targeted capture sequencing identified 994 different variants. Among them, 98 variants were classified as pathogenic/likely pathogenic variants; 38 were novel variations. A total of 39 patients had the pathogenic/likely pathogenic variants. Among them, 75 (36%) patients were genetically confirmed, and 18 (9%) patients had one heterozygous variant of recessive myopathy. However, two genetically confirmed patients had an additional heterozygous variant of another recessive myopathy. Four patients with one heterozygous variant of a recessive myopathy showed different phenotypes, compared with the known phenotype of the identified gene. The major causative genes of Korean patients with IMDs were DMD (19 patients), COL6A1 (9), DYSF (9), GNE (7), LMNA (7), CAPN3 (6), and RYR1 (5). This study showed the mutational and clinical spectra in Korean patients with IMD and confirmed the usefulness of strategies utilizing targeted sequencing.

Glutathione S-transferase M1 (GSTM1) polymorphism is associated with atopic dermatitis susceptibility in a Korean population.

Atopic dermatitis (AD) is a chronic pruritic skin condition affecting as much as 15% of children in industrialized countries. While the underlying pathophysiology of AD is not entirely understood, several studies have suggested that AD may mediated by oxidative stress. Glutathione S-transferases (GSTs) are a class of polymorphic enzymes that function to protect against oxidative stress. To identify any possible associations between GSTs polymorphisms and AD susceptibility, the prevalence of two specific polymorphisms -GSTM1 and GSTT1 (homozygous deletion vs. undeleted) - were quantified by multiplex PCR in 145 patients with AD and 267 healthy controls. In individuals with AD, GSTM1/GSTT1 polymorphisms were compared with family history of AD, age of disease onset, disease severity [per SCORing Atopic Dermatitis (SCORAD)], serum IgE level and presence of other allergic diseases. While the GSTM1-null genotype was found to be significantly associated with AD (P = 0.033, OR = 1.579, 95% CI = 1.037-2.403), the correlation between the GSTT1-null genotype and AD did not reach statistical significance (P = 0.577, OR = 1.125, 95% CI = 0.744-1.702). The GSTM1-null genotype was also found to be significantly associated with a childhood onset of AD, the absence of other allergic diseases, and a family history of AD. In combination, these results suggest that GSTM1 is associated with AD susceptibility in Korean subjects.

Transforming growth factor beta receptor II (TGFBR2) polymorphisms and the association with nonsegmental vitiligo in the Korean population.

The precise cause of vitiligo is unknown. However, autoimmunity is considered the most likely aetiology, especially in nonsegmental vitiligo (NSV). In this study we determined whether or not the transforming growth factor beta receptor II (TGFBR2) gene contributes to susceptibility for NSV in the Korean population. Blood samples were collected from 415 controls and 233 cases. We selected three single nucleotide polymorphisms (SNPs) in the TGFBR2 gene. The genotypes of the SNPs were determined using direct sequencing. All of the SNPs were significantly different between the vitiligo patients and controls (rs2005061, co-dominant, dominant, recessive, P < 0.05; rs3773645, co-dominant, dominant, recessive, P < 0.05; rs3773649, co-dominant, recessive, P < 0.05). In addition, haplotype 1 (CG) and haplotype 2 (GA) of the linkage disequilibrium (LD) block were also associated with a risk of NSV. The present study suggests that TGFBR2 might be related to NSV.

The interleukin-1 family gene polymorphisms in Korean patients with rheumatoid arthritis.

OBJECTIVE: The interleukin (IL)-1 family and its related family members are primary inflammatory cytokines. The aim of this study was to assess the possible association between nine IL-1 family gene polymorphisms and rheumatoid arthritis (RA). METHODS: To investigate the genetic association between IL-1 family gene polymorphisms and the risk of RA in a Korean population, 69 single nucleotide polymorphisms (SNPs) of the nine IL-1 family gene regions were selected. A total of 806 subjects (498 controls and 308 RA patients) were included in the study. The genotypes of the selected SNPs in the IL-1 family genes were determined using Illumina Sentrix Array Matrix chips. SNP Stats, Haploview, and SNP Analyzer, and Helixtree programs were used for the analysis of the genetic data. RESULTS: We observed statistically significant associations between the SNPs of IL1F10 and IL1RN among the IL-1 family genes in the RA patients and the control population. When the patients were divided into two groups according to the parameters of disease activity, including C-reactive protein (CRP) level (> or = 0.5 or < 0.5 mg/dL), the erythrocyte sedimentation rate (ESR) (> or = 30 or < 30 mm/h), and parameters of severity, including rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP), and bone erosion (positive or not), we found significant associations between the parameters, including CRP, ESR, and bone erosion, and SNPs of the IL-1 family genes in RA. CONCLUSION: This study suggests that IL-1 family gene (IL1F10 and IL1RN) polymorphisms may play an important role in the susceptibility to developing RA.

Topiramate stimulates glucose transport through AMP-activated protein kinase-mediated pathway in L6 skeletal muscle cells.

The use of topiramate (TPM) in the treatment of binge-eating disorder, bulimia nervosa, and antipsychotic-induced weight gain has recently increased, however, the exact molecular basis for its effects on body weight reduction and improved glucose homeostasis, is yet to be elucidated. Here we investigated the effect and signaling pathway of TPM on glucose uptake in L6 rat skeletal muscle cells, which account for >70% of glucose disposal in the body. Intriguingly, we found that TPM (10 microM) stimulated the rate of glucose uptake up to twofold increase. And TPM-stimulated glucose transport was inhibited with the overexpression of dominant-negative form of AMP-activated protein kinase (AMPK), an important mediator in glucose transport, implicating that AMPK-mediated pathway is involved. The TPM-stimulated glucose transport was blocked by SB203580, a specific inhibitor of AMPK downstream mediator, p38 mitogen-activated protein kinase (MAPK) protein. LY294002, an inhibitor of phosphatidylinositol (PI) 3-kinase, which is another crucial mediator in independent glucose transport pathway, did not inhibit TPM-stimulated glucose transport. We also found that TPM increased the phosphorylation level of AMPK and p38 MAPK, whereas no effect on the activity of PI 3-kinase of TPM, when assessed by PI 3-kinase assay, was observed. These results together suggest that TPM stimulates glucose transport, not via PI 3-kinase mediated, but via AMPK-mediated pathway in skeletal muscle cells, thereby contributing to the body weight regulation and glucose homeostasis.

Quantitation of niflumic acid in human plasma by high-performance liquid chromatography with ultraviolet absorbance detection and its application to a bioequivalence study of talniflumate tablets.

A rapid and simple HPLC method with UV detection (288 nm) was developed and validated for quantitation of niflumic acid in human plasma, the active metabolite of talniflumate. After precipitation with 100% methanol containing the internal standard, indomethacin, the analysis of the niflumic acid level in the plasma samples was carried out using a reverse phase C18 CAPCELL PAK (5 microm, 4.6 mm x 250 mm) column. The chromatographic separation was accomplished with an isocratic mobile phase consisting of a mixture of 0.1M sodium acetate in water and acetonitrile (37:63, v/v), adjusted to pH 6.4. This HPLC method was validated by examining its precision and accuracy for inter- and intra-day runs in a linear concentration range of 0.02-5.00 microg/mL. Stability of niflumic acid in plasma was excellent, with no evidence of degradation during sample processing (autosampler) and 30 days storage in a freezer. This validated method was successfully applied to the bioequivalence study of talniflunate in healthy volunteers.

Fluoxetine enhances cell proliferation and prevents apoptosis in dentate gyrus of maternally separated rats.

The mother-infant relationship is an instinctive phenomenon, and loss of maternal care in early life influences neonatal development, behavior and physiologic responses.(1,2) Furthermore, the early loss may affect the vulnerability of the infant to neuropsychiatric disorders, such as childhood anxiety disorders, personality disorders and depression, over its lifespan.(3,4) Fluoxetine is prescribed worldwide for depression and is often used in the treatment of childhood mental problems related to maternal separation or loss of maternal care.(5,6) In the present study, fluoxetine was administrated to rats with maternal separation to determine its effects on neuronal development, in particular with respect to cell proliferation and apoptosis in the dentate gyrus of the hippocampus. Rat pups were separated from their mothers and socially isolated on postnatal day 14 and were treated with fluoxetine (5 mg kg(-1)) and 5-bromo-2'-deoxyuridine (BrdU) (50 mg kg(-1)) for 7 days, after which immunohistochemistry and a terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining were carried out. In the pups with maternal separation treated with fluoxetine, the number of BrdU-positive cells was significantly increased and that of TUNEL-positive cells was significantly decreased in the dentate gyrus compared to pups with maternal separation that did not receive fluoxetine treatment. These findings indicate that fluoxetine affects new cell proliferation and apoptosis, and we propose that fluoxetine may be useful in the treatment of maternal separation-related diseases.

Increases in cell proliferation and apoptosis in dentate gyrus of anorexia (anx/anx) mice.

The homozygous anorexia mutant (anx/anx) mice present with premature death during the third or fourth postnatal week: this phenotype is caused by a lethal mutation, anx, on chromosome 2, which has an autosomal recessive mode of inheritance. These animals also present phenotypically with decreased food intake, weight loss, and neurological deficits such as hyperactivity, body tremors, uncoordinated gait, and head weaving. In order to investigate changes in the occurrence of cell proliferation and apoptosis in the dentate gyrus of the hippocampus of anx/anx mice, 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay were performed in this study. In addition, the volume of the dentate gyrus was estimated via stereological analysis. anx/anx mice showed significantly higher numbers of both BrdU- and TUNEL-positive cells in the dentate gyrus than those of the control mice. Furthermore, the volume of the dentate gyrus of anx/anx mice was significantly reduced compared to that of the control mice.

Acupuncture increases cell proliferation in dentate gyrus after transient global ischemia in gerbils.

The effects of acupuncture on cell proliferation in the dentate gyrus of gerbils after transient global ischemia were investigated in this study. Acupuncture was performed on Zusanli (ST36), which is a well known acupoint in animals and humans. In Oriental medicine, Zusanli has been commonly used for the enhancement of functional recovery in stroke patients. Through 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry, an increase in cell birth in the dentate gyrus of gerbils after ischemic injury was detected. Interestingly, acupunctural treatment in ischemic gerbils resulted in a significant increase in the number of BrdU-positive cells in the dentate gyrus. The present findings indicate that acupuncture may affect cell proliferation in the dentate gyrus of gerbils after ischemic injury.

Protective effects of puerariaeflos against ethanol-induced apoptosis on human neuroblastoma cell line SK-N-MC.

Puerariaeflos (PF) is an oriental medical herb for alcohol abuse. To investigate whether PF possesses protective effects against ethanol (EtOH)-induced cytotoxicity in the central nervous system, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometric analysis, DNA fragmentation assay, and reverse transcription-polymerase chain reaction were performed on SK-N-MC human neuroblastoma cells. Cells treated with EtOH exhibited several apoptotic features, while those pre-treated with PF prior to EtOH exposure showed a decreased occurrence of apoptotic features. In addition, PF pre-treatment inhibited the EtOH-induced increase in caspase-3 mRNA expression. These results suggest that PF may exert protective effects against EtOH-induced apoptosis in human neuroblastoma cells.

Serotonin induces apoptosis in PGT-beta pineal gland tumor cells.

Serotonin-induced neuronal cell death has been implicated as a possible cause of neurodegenerative and neuropsychiatric disorders. To investigate the involvement of serotonin-induced apoptosis as a potential mechanism in the pathophysiology of serotonin-related diseases, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, DAPI (4',6-diamidino-2-phenylindole) staining, TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling) assay and flow cytometric analysis were performed using the immortalized pineal cell line PGT-beta. Through morphological and biochemical analyses, it was demonstrated that cell death induced by serotonin in PGT-beta cells shows classic apoptotic features. These data suggest that serotonin induces apoptosis in PGT-beta cells.

Identification and sequencing of pineal-specific enhancing region in the mouse tryptophan hydroxylase promoter.

Pineal-specific expression of the tryptophan hydroxylase (TPH) gene has been demonstrated by a number of studies. However, little is known about the regulatory mechanism for pineal-specific expression of the TPH gene. To identify the cis-acting region responsible for pineal-specific expression of the TPH gene, we investigated a 6.1-kb 5'-flanking region of the mouse TPH gene using an immortalized pineal cell line (PGT-beta) derived from transgenic mice. By deletion analysis, it was demonstrated that the pineal-specific enhancing region resides approximately between -6.1 and -4.7 kb upstream from the transcription initiation site of the mouse TPH gene. Additionally, nucleotide sequence analysis of this region showed that the (AC/TG)22 repetitive sequence is located approximately -5.78 kb upstream of the mouse TPH gene, and several known tissue-specific cis-acting elements, such as Pit-1 and the pituitary specific element (PSE), have also been identified in the region. We believe that the analysis of the sequence and several cis-acting elements in the pineal-specific enhancing region of the mouse TPH promoter would enhance our understanding of the precise mechanism of pineal-specific expression.