Heat Stress during Summer Attenuates Expression of the Hypothalamic Kisspeptin, an Upstream Regulator of the Hypothalamic-Pituitary-Gonadal Axis, in Domestic Sows.

The release of reproductive hormones in the hypothalamic-pituitary-gonadal (HPG) axis is regulated by its upstream regulator, kisspeptin, and influenced by external stresses, including heat stress. Since the effect of heat stress (summer infertility) on hypothalamic kisspeptin expression in domestic sows is not yet understood, the present study attempted to identify changes in kisspeptin expression in different seasons (summer and spring). The high atmospheric temperature in summer decreased the pregnancy rate and litter size and increased stress-related hormones as a chronic stressor to domestic sows. The hypothalamic kisspeptin expression in summer was decreased regardless of the estrus phase and negatively correlated with atmospheric temperature, indicating that high temperature decreased kisspeptin. When the activity of hypothalamic kisspeptin neurons in the follicular phase was assessed using c-Fos staining, a decreased number of kisspeptin neurons coexpressing c-Fos was observed in domestic sows in summer. Accordingly, lower expression of kisspeptin induced decreased levels of HPG axis-related reproductive hormones, such as gonadotropins and estrogen, and fewer large ovarian follicles. In conclusion, the present study demonstrated that reduced kisspeptin expression and its neuronal activity in the hypothalamus under heat stress in summer induced downregulation of the HPG axis and caused summer infertility in domestic sows.

Association of CCL11 promoter polymorphisms with schizophrenia in a Korean population.

BACKGROUND: Immunological alterations and dysregulation of the inflammatory response have been suggested to play a crucial role in schizophrenia pathophysiology. Growing evidence supports the involvement of chemokines in brain development, thus many chemokines have been studied in relation with schizophrenia. The C-C motif chemokine ligand 11 (CCL11) has been shown to be related with synaptic plasticity and neurogenesis. Moreover, altered levels of CCL11 have been observed in schizophrenia patients. Therefore, we examined whether single nucleotide polymorphisms (SNPs) of the CCL11 in the promoter region contribute to susceptibility to schizophrenia. METHODS: Four promoter SNPs [rs17809012 (-384T>C), rs16969415 (-426C>T), rs17735961 (-488C>A), and rs4795896 (576G>A)] were genotyped in 254 schizophrenia patients and 405 control subjects using Fluidigm SNPtype assays. RESULTS: The genotype frequency of CCL11 rs4795896 (-576G>A) showed significant association with schizophrenia in a recessive model (AA vs. GG/AG, p < 0.0001) and in a log-additive model (AG vs. AA vs. GG, p < 0.0001). The allele frequency of rs4795896 also showed a significant association with schizophrenia (p < 0.0001). Furthermore, haplotype analysis revealed that GCT, ACT, and GCC haplotypes containing rs4795896, rs17735961 and rs17809012 were significantly associated with schizophrenia (p = 0.0044, p < 0.0001, and p < 0.0001, respectively). CONCLUSION: Our results suggest that CCL11 promotor polymorphism is associated with increased risk for the development of schizophrenia in a Korean population.

BBOX1 is down-regulated in maternal immune-activated mice and implicated in genetic susceptibility to human schizophrenia.

Prenatal exposure to infectious or inflammatory insults can increase the risk of developing neuropsychiatric disorders such as bipolar disorder, autism, and schizophrenia in later life. Gamma-butyrobetaine hydroxylase (BBOX 1) is an enzyme responsible for the biosynthesis of l-carnitine, a key molecule in fatty acid metabolism. This cytosolic dimeric protein belongs to the dioxygenase family. In this study, we investigated whether BBOX 1 expression was related to psychiatric disorder in an animal model. We also conducted a case-control study using 284 schizophrenia patients and 409 controls with single-nucleotide polymorphisms (SNPs) in the 5'-near region of BBOX 1. BBOX 1 expression was increased in the medial frontal cortex of a mouse model of schizophrenia induced by maternal immune activation. Furthermore, the genotype and allele frequencies of two SNPs (rs7939644 and rs10767592) were significantly associated with schizophrenia susceptibility. Our results suggest that BBOX 1 might be associated with maternal immune activation and schizophrenia susceptibility. Therefore, it might be involved in the pathophysiology of schizophrenia.

A pilot study of differential brain activation to suicidal means and DNA methylation of CACNA1C gene in suicidal attempt patients.

Suicide is a serious public health problem. In this study, we investigated functional brain changes to novel visual stimuli of suicidal means, DNA methylation status, and the relationship between the two markers. 14 suicidal attempt patients (SAs) and 22 healthy controls were included. Pictures of facial expressions and suicidal means were shown to subjects during fMRI scanning. 11 CpG sites within transcription factor binding site of CACNA1C gene were selected. In knives (K) vs. natural landscape (NL) condition, left middle frontal gyrus (Brodmann's area, BA 6 and 46) and left inferior frontal gyrus (BA 9) were shown to be significantly higher brain activation in the SAs than the controls (p<0.001). DNA methylation percentages of CpG site 4 (p=0.005) and 6 (p=0.037) were found to be related to the SAs. In the SAs, methylation degree of site 4 and site 6 was positively correlated with signal intensity of K vs. NL condition in left thalamus. The degree of site 4 was positively correlated with signal intensity in left middle and inferior frontal gyri in SAs. The possibility that these findings might be involved in the neurobiology of suicidal behavior is suggested.

Factors Related to Noncompliance in Screening and Tracking Mild Cognitive Impairment Patients in a Single Community.

OBJECTIVE: We assessed the cumulative conversion rates (CCR) from minor cognitive impairment (MCI) to dementia among individuals who failed to participate in annual screening for dementia. Additionally, we analyzed the reasons for failing to receive follow-up screening in order to develop better strategies for improving follow-up screening rates. METHODS: We contacted MCI patients who had not visited the Dongdaemun-gu Center for Dementia for annual screening during the year following their registration. We compared the CCR from MCI to dementia in the following two groups: subjects registered as having MCI in the Dongdaemun-gu Center for Dementia database and subjects who failed to revisit the center, but who participated in a screening test for dementia after being contacted. The latter participants completed a questionnaire asking reasons for not previously visiting for follow-up screening. RESULTS: The final diagnoses of the 188 subjects who revisited the center only after contact were 19.1% normal, 64.9% MCI and 16.0% dementia. The final diagnoses of the 449 subjects in the Dongdaemun-gu Center for Dementia database were 25.6% normal, 46.1% MCI and 28.3% dementia. The CCR of the revisit-after-contact group was much lower than anticipated. The leading cause for noncompliance was "no need for tests" at 28.2%, followed by "other reasons" at 23.9%, and "I forgot the appointment date" at 19.7%. CONCLUSION: Considering the low dementia detection rate of the group who revisited only after contact and the reasons they gave for noncompliance, there appears to be a need for ongoing outreach and education regarding the course and prognosis of MCI.

Association between Mitofusin 2 Gene Polymorphisms and Late-Onset Alzheimer's Disease in the Korean Population.

OBJECTIVE: Mitochondrial dysfunction is a prominent and early feature of Alzheimer's disease (AD). The morphologic changes observed in the AD brain could be caused by a failure of mitochondrial fusion mechanisms. The aim of this study was to investigate whether genetic polymorphisms of two genes involved in mitochondrial fusion mechanisms, optic atrophy 1 (OPA1) and mitofusin 2 (MFN2), were associated with AD in the Korean population by analyzing genotypes and allele frequencies. METHODS: One coding single nucleotide polymorphism (SNP) in the MFN2, rs1042837, and two coding SNPs in the OPA1, rs7624750 and rs9851685, were compared between 165 patients with AD (83 men and 82 women, mean age 72.3±4.41) and 186 healthy control subjects (82 men and 104 women, mean age 76.5±5.98). RESULTS: Among these three SNPs, rs1042837 showed statistically significant differences in allele frequency, and genotype frequency in the co-dominant 1 model and in the dominant model. CONCLUSION: These results suggest that the rs1042837 polymorphism in MFN2 may be involved in the pathogenesis of AD.

Association between IRS1 Gene Polymorphism and Autism Spectrum Disorder: A Pilot Case-Control Study in Korean Males.

The insulin-like growth factor (IGF) pathway is thought to play an important role in brain development. Altered levels of IGFs and their signaling regulators have been shown in autism spectrum disorder (ASD) patients. In this study, we investigated whether coding region single-nucleotide polymorphisms (cSNPs) of the insulin receptor substrates (IRS1 and IRS2), key mediators of the IGF pathway, were associated with ASD in Korean males. Two cSNPs (rs1801123 of IRS1, and rs4773092 of IRS2) were genotyped using direct sequencing in 180 male ASD patients and 147 male control subjects. A significant association between rs1801123 of IRS1 and ASD was shown in additive (p = 0.022, odds ratio (OR) = 0.66, 95% confidence interval (CI) = 0.46-0.95) and dominant models (p = 0.013, OR = 0.57, 95% CI = 0.37-0.89). Allele frequency analysis also showed an association between rs1801123 and ASD (p = 0.022, OR = 0.66, 95% CI = 0.46-0.94). These results suggest that IRS1 may contribute to the susceptibility of ASD in Korean males.

Association of tripartite motif family-like 2 (TRIML2) polymorphisms with late-onset Alzheimer's disease risk in a Korean population.

Apoptosis is a prominent feature in the progression of Alzheimer's disease (AD), regulated in part by the activity of p53. As tripartite motif family-like 2 (TRIML2), a member of the TRIM family of proteins, has been implicated in the regulation of p53-mediated apoptosis, we hypothesized that TRIML2 polymorphisms may result in an increased AD susceptibility. Here, we investigated the association between coding region single nucleotide polymorphisms (cSNPs) in TRIML2 and AD in a Korean population. Two cSNPs (rs79698746 and rs2279551) were genotyped using the Sequenom iPLEX(®) Gold assay and direct sequencing in 162 AD patients and 191 controls. Multiple logistic regression models were used to determine the odds ratios, 95% confidence intervals, and p-values. Significant associations were observed between AD and the allelic frequencies of two SNPs (rs79698746, p=0.007; rs2279551, p=0.01); genotype frequencies were also significantly different between the two groups [rs79698746: p=0.003 in the codominant 2 model (CC vs. TT), p=0.01 in the dominant model (TC/CC vs. TT), p=0.016 in the recessive model (CC vs. TT/TC), and p=0.0025 in the log-additive model (TC vs. CC vs. TT); rs2279551: p=0.003 in the codominant 2 model (CC vs. TT), p=0.011 in the dominant model (TC/CC vs. TT), p=0.019 in the recessive model (CC vs. TT/TC), and p=0.0028 in the log-additive model (TC vs. CC vs. TT)]. In the haplotype analyses, CC haplotypes containing two cSNPs were significantly associated with AD (p=0.013). Taken together, these findings indicate that the C allele of both SNPs was associated with an increased risk of AD. These results suggest that TRIML2 may contribute to AD susceptibility.

Potential involvement of NET polymorphism in serotonin/norepinephrine reuptake inhibitor response in panic disorder.

BACKGROUND: This is a pilot study assessing the impact of polymorphisms of serotonin transporter (5-HTT; 5-HTTLPR (S/L)) and norepinephrine transporter (NET; rs2242446 (T/C)) genes on selective serotonin reuptake inhibitors (SSRIs) and serotonin/norepinephrine reuptake inhibitors (SNRIs) response in Korean panic disorder (PD) patients. METHODS: PD patients were treated with SSRI (n = 18) or SNRI (n = 6) for 4 weeks. Panic Disorder Severity Scale (PDSS) was rated to evaluate the treatment response. Wilcoxon signed-rank test was used to compare PDSS scores before and after medication (SSRI or SNRI) as well as to compare those according to genotypes. Mann-Whitney U test was used to compare those between the two groups (SSRI or SNRI). RESULTS: Both SSRI and SNRI treatments for 4 weeks significantly reduced PDSS scores. We assessed the impact of rs2242446 on this effect of SSRI and SNRI. The scores were significantly decreased after 4 weeks in the SSRI-treated group regardless of genotypes of rs2242446, whereas they were significantly decreased in the SNRI-treated group with only non-C carrier (TT) of rs2242446. On 5-HTTLPR we could not analyse because 22 patients had SS genotype. CONCLUSIONS: These results suggest that NET polymorphism may affect the SNRI response in Korean PD patients.

Optimizing the preparation conditions and characterization of cross-linked enzyme aggregates of a monoamine oxidase.

Monoamine oxidases are useful in determination of biogenic monoamines, particularly histamine and tyramine. In this study, cross-linked enzyme aggregates (CLEAs) technique was applied to improve the stability of a monoamine oxidase from Arthrobacter aurescens (AMAO). Under the optimized condition (50% of saturated ammonium sulfate, 5 mM glutaraldehyde, 2.0 mg/mL AMAO, 4 h-cross-linking at 25°C, pH 8.0), CLEAs-AMAO was recovered with a yield of 82% based on the subjected total enzyme activity. Both pH activity and stability at alkaline pHs of CLEAs-AMAO were significantly improved compared to those of the free enzyme, resulting in the shift of optimum pH to pH 8.0 and a broader pH profile. The half-life of the CLEAs at 65°C was elongated by 1.7-fold compared to that of the free enzyme, suggesting the thermal stability of AMAO was also improved by the CLEAs formation.

LAMB1 polymorphism is associated with autism symptom severity in Korean autism spectrum disorder patients.

BACKGROUND: LAMB1 encodes laminin beta-1, which is expressed during early development of the human nervous system, and could be involved in the pathogenesis of neurodevelopmental disorders. AIMS: In our study, we aimed to investigate whether single nucleotide polymorphisms (SNPs) in LAMB1 were associated with autism spectrum disorder (ASD) and with related clinical severities of ASD. METHODS: Two coding SNPs (rs20556 and rs25659) and two intronic SNPs (rs2158836 and rs2237659) were compared between 180 patients with ASD and 147 healthy control subjects using direct sequencing. The Korean version of the Childhood Autism Rating Scale (K-CARS) was used to assess clinical severities. Multiple logistic regression models were employed to analyze genetic data, and associations with symptom severity were tested with the Kruskal-Wallis and the Mann-Whitney U tests. RESULTS: None of the four examined SNPs was associated with ASD risk. However, the GG genotype of rs2158836 was associated with more severe symptoms for the "object use" and "non-verbal communication" measures. CONCLUSIONS: The results of our study suggest the association between rs2158836 polymorphisms and symptom severity in ASD.

Ibulocydine sensitizes human cancers to radiotherapy by induction of mitochondria-mediated apoptosis.

BACKGROUND AND PURPOSE: Ibulocydine (IB), a novel prodrug of CDK inhibitor, has been reported to have anti-cancer effect in human hepatoma cells. In order to address its feasibility as a radiosensitizer to improve radiotherapeutic efficacy for human cancers, this study was designed. MATERIAL AND METHODS: Human cancer cells of lung and colon were treated with IB and/or radiotherapy (RT). The cellular effects were assessed by CCK-8, clonogenic, flow cytometric, and western blotting assays. In vivo radiotherapeutic efficacy was evaluated using the xenograft mouse model. RESULTS: Combined treatment of IB and RT significantly reduced viability and survival fraction of the cells. Apoptotic cell death accompanied with activation of caspases, decrease in Bcl-2/Bax expression, loss of mitochondrial membrane potential (MMP) leading to release of cytochrome c into cytosol was observed. Recovery of Bcl-2 expression level by introducing Bcl-2 expressing plasmid DNA compromised the loss of MMP and apoptosis induced by IB and RT. In vivo therapeutic efficacy of combined treatment was verified in the xenograft mouse model, in which tumor growth was markedly delayed by RT with IB. CONCLUSIONS: IB demonstrated the property of sensitizing human cancer cells to RT by induction of mitochondria-mediated apoptosis, suggesting that IB deserves to be applied for chemoradiotherapy.

Ibulocydine is a novel prodrug Cdk inhibitor that effectively induces apoptosis in hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) is frequently associated with abnormalities in cell cycle regulation, leading to increased activity of cyclin-dependent kinases (Cdks) due to the loss, or low expression of, Cdk inhibitors. In this study, we showed that ibulocydine (an isobutyrate prodrug of the specific Cdk inhibitor, BMK-Y101) is a candidate anti-cancer drug for HCC. Ibulocydine has high activity against Cdk7/cyclin H/Mat1 and Cdk9/cyclin T. Ibulocydine inhibited the growth of HCC cells more effectively than other Cdk inhibitors, including olomoucine and roscovitine, whereas ibulocydine as well as the other Cdk inhibitors and BMK-Y101 minimally influenced the growth of normal hepatocyte cells. Ibulocydine induced apoptosis in HCC cells, most likely by inhibiting Cdk7 and Cdk9. In vitro treatment of HCC cells with ibulocydine rapidly blocked phosphorylation of the carboxyl-terminal domain (CTD) of the large subunit of RNA polymerase II, a process mediated by Cdk7/9. Anti-apoptotic gene products such as Mcl-1, survivin, and X-linked IAP (XIAP) are crucial for the survival of many cell types, including HCC. Following the inhibition of RNA polymerase II phosphorylation, ibulocydine caused rapid down-regulation of Mcl-1, survivin, and XIAP, thus inducing apoptosis. Furthermore, ibulocydine effectively induced apoptosis in HCC xenografts with no toxic side effects. These results suggest that ibulocydine is a strong candidate anti-cancer drug for the treatment of HCC.

Xylocydine, a novel Cdk inhibitor, is an effective inducer of apoptosis in hepatocellular carcinoma cells in vitro and in vivo.

Hepatocellular carcinoma (HCC) frequently includes abnormalities in cell cycle regulators, including up-regulated cyclin-dependent kinase (Cdks) activities due to loss or low expression of Cdk inhibitors. In this study, we show that xylocydine, a cyclin-dependent kinase (Cdk) specific inhibitor, is a good anti-cancer drug candidate for HCC treatment. Xylocydine (50muM) selectively down-regulates the activity of Cdk1 and Cdk2, accompanied by significant cell growth inhibition in HCC cells. Xylocydine also strongly inhibits the activity of Cdk7 and Cdk9, in vitro as well as in cell cultures, that is temporally associated with apoptotic cell death in xylocydine-induced HCC cells. This is associated with inhibition of phosphorylation of RNA polymerase II at serine residues 5 and 2, which are targets of Cdk7 and Cdk9, respectively. The effects on apoptosis are concomitant with changes in the levels of anti-apoptotic proteins, Bcl-2, XIAP, and survivin, which are markedly down-regulated, and pro-apoptotic molecules, p53 and Bax, which are elevated in HCC cells after treatment with xylocydine. The up-regulated level of p53 was associated with increased stability of the protein, as levels of Ser15 and Ser392 phsophorylated p53 are similarly elevated in the inhibitor treated cells. We demonstrated that xylocydine can effectively suppress the growth of HCC xenografts in Balb/C-nude mice by preferentially inducing apoptosis in the xenografts, whereas the drug did not cause any apparent toxic effect on other tissues. Taken together, these data suggest that the novel Cdk inhibitor xylocydine is a good candidate for an anti-cancer drug for HCC therapy.