20 research outputs found
Lower Erythrocyte GST activity in Autism Spectrum Disorder (ASD) patients compared to normal controls
Glutathione S-transferases (GST) are antioxidant enzymes that play an important role in the cellular detoxification and excretion of environmental pollutants including heavy metals. GST mu (GSTM1) and G theta (GSTT1) are known to be
highly polymorphic and homozygous deletions of these genes result in the lack of enzyme activity and when combined
with decreased levels of antioxidants, they have been associated with the Autism Spectrum Disorder (ASD). This
preliminary study was performed to investigate the role of GSTM1 and GSTT1 polymorphisms as risk factors of ASD
associated with GST activity and phenotype expression. Fifty one ASD patients and 45 controls were recruited for
GSTM1 and GSTT1 genotyping while 6 ASD patients and 8 controls were assessed for GST activity. The results showed
no significant differences in frequencies of GSTM1 null, GSTT1 null and combination both genotype between ASD
patients and controls. However the mean erythrocyte GST activity in ASD is significantly decreased compared with
controls (p = 0.043). The mean erythrocyte GST activity is lower in the severely autistic group compare to the mild to
moderately autistic group, although it was not statistically significant. Further investigations are needed with a bigger sample size, analyzing multiple GST genes and GST activity determination to find out the gene susceptibility of ASD and factors that contribute to the phenotype expression of ASD
Screening for HLA-B*1502 Polymorphism in Febrile Seizure Predicted Lead to Epilepsy
Mutation in neuronal sodium channel -1-subunit gene (SCN1A) and neuronal sodium channel -1-subunit gene (SCN1B) has been linked with forms of generalized epilepsy with febrile seizure plus (GEFS+) and epileptic infantile syndrome like severe myoclonic epilepsy of infancy (SMEI) (Mulley et al., 2005; Scheffer et al., 2007). Since this idiopathic epilepsy typically begins with prolonged febrile seizures (FS) in the first year of life, therefore febrile seizure patient with mutation in SCN1A has a high risk to develop epilepsy on their later life (Dube et al., 2009). Carbamazepine (CBZ) has been known as the most common anti-epileptic drug which can cause Steven-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) in patients with HLA-B*1502 polymorphism. Since the Javanese population have 16,67% of these allele, studying the presence of these allele in patients predicted epilepsy is important.
Furthermore, this study was intended to develop a PCR-based diagnostic protocol to screen HLA-B*1502 polymorphism in epileptic patients to prevent SJS/TEN by carbamazepine. Focusing on epileptic predicted patients, HLA-B*1502 genotyping by sequence specific primer (SSP)-PCR was performed on 31 repeated FS patients with mutation in SCN1A and SCN1A/SCN1B gene.
The result show that the HLA-B*1502 polymorphism was detected in 14 (45,2%) individuals including 8 cases related to mutation SCN1A gene and 6 to SCN1A/SCN1B gene. It illustrates that HLA-B*1502 allele is frequent in these patients. It can thus be suggested that detection of this allele should be done before epilepsy treatment. Later, patients with this allele should avoid CBZ to prevent SJS/TEN during drug administration
Are GSTM1 Null and GSTT1 Null Risk Factor of Autism Spectrum Disorder? a Preliminary Study
Background: Low plasma total glutathione (tGSH) levels, elevated levels of oxidized glutathione (GSSG) and low ratios of tGSH to GSSG in autism were reported. Glutathione S-transferases (GST) are antioxidant enzymes that play important role in cellular detoxification and the excretion of environmental pollutants including heavy metals. Glutathione S-transferase mu (GSTM1) and Glutathione S-transferase theta (GSTT1) are known to be highly polymorphic. Homozygous deletions of these genes result in lack ofenzyme activity and impaired the ability to excrete metals including mercury. Combined effects of mercury (Hg) accumulation coupled with decreased levels of antioxidants (low glutathione and antioxidant enzymes) contribute to the phenotypic presentation of autism spectrum disorder (ASD). Association of GSTM1 null genotype with autism has been reported. Therefore the preliminary study was performed to investigate the role of GSTM1 null and GSTT1 null as risk factor of ASD associated with phenotype expression.Method: Fifty one ASD patients were recruited from special need & autism school and 45 controls from Semarang & Solo. Blood veins samples were collected and genomic DNA was extracted by salting-out method in CEBIOR Semarang. Genotyping for GSTM1 and GSTT1 gene was done in UMBI Malaysia. Multiplex PCR was performed and PCR products were separated on 1.2 % agarose gel, stained with ethidium bromide and visualized on UV transiluminator. GSTM1 & GSTT1 gene product is about 625 bp and 459 bp. Absence of GSTM1 and GSTT1 gene band was interpreted as GSTM1 null & GSTT1 null.Results: The frequency of GSTM1 null and GSTT1 null in ASD higher compared with control group but the difference is not statistically significant (p=0.357, OR=0.504; 95% CI 0.117-2.168 and p=0.364, OR=0.674; 95% CI 0.287-1.580). There is also no statistically different in the distribution of GSTM1 null and GSTT1 null between mild to moderately autistic and severely autistic (p=0.983, OR=0.980; 95% CI 0.158-6.095 and p=0.439, OR=1.633; 95% CI 0.471-5.656).Conclusion: GSTM1 null and GSTT1 null are not risk factor of ASD. Further investigations are needed with a bigger sample size, analyzing multiple GST genes and GST activity determination to find out the gene susceptibility of ASD and factors that contribute to the phenotype expression of ASD
Expression profile of late responsive genes induced by spatial learning task: involvement of pathways in locomotion and memory
The altered molecular mechanisms by experimental therapies for neurodegenerative diseases itself could be overlapped with genes induced by the behavioral task. We employed the microarray platform to identify the differentially expressed late responsive genes in medial temporal lobes of four Morris Water Maze (MWM) trained and untrained BALB/c mice. After MWM training, the mice were sacrificed to obtain their brains’ medial temporal lobes. The total RNA was extracted from the tissues and global mRNA gene expression analysis was performed using Affymetrix GeneChip ®Mouse Gene 1.0 ST Array. There were 3635 (62.2%) up-regulated genes and 2206 (37.8%) down-regulated genes at p-values of < 0.05. These genes were operationally defined as late memory-related genes and behavior-related genes indicating that behavioral learning has a significant impact on the gene expression of the medial temporal lobes. From the pathway analysis, the network of memory and locomotion genes, and the guanylate cyclase pathway were identified as one of the most interesting pathways. The qPCR validation showed that the genes NMDA receptor 2a (Nmda2a) and cAMP dependent protein kinase type I beta regulatory subunit (Prkar1b) were up-regulated while adenylate cyclase 5 (Adcy5) was down-regulated. We proposed that the involvement of guanylate cyclase pathway in the long-term potentiation lasted at least up to three days after the MWM test. Present study suggested that the molecular mechanisms followed by spatial learning task could be altered up to three days or even longer, it could be overlapped with genes induced by further invented experimental therapy
Multi-generational culture of c. elegans on a long-term space flight revealed changes in expression of genes involved in longevity, DNA repair,and locomotion
Scientists are trying to determine the long term effects of exposure to microgravity and space radiation on various cellular and biological functions. We used C. elegans as the model organism to study the changes in gene expression. Wild type worms were grown in a liquid medium using the CHab hardware. The CHab was flown on the STS116 flight to the International Space Station (ISS) and returned to earth on the STS118 flight. Upon landing, surviving worms were extracted and RN Alater added. Ground controls were grown at Bioserve in Colorado and passaged synchronously. RN A was later extracted and mRN A gene expression was analysed using Affymetrix GeneChip® C. elegans Genome Array. The results revealed that 858 known genes were differentially expressed (p-value ≤ 0.05 and fold change ≥ ± 2); namely 608 genes were up-regulated and 250 genes down-regulated. The genes dod-19 and dod-3 which are the downstream effectors of the forkhead transcription factor daf-16 were up-regulated. Daf-16 regulates insulin/TGF signaling pathway that influence metabolic alterations, increased stress and microbial resistance. The glutathione S-transferase (gst-1), Flavin-containing MonoOxygenase (fmo-3) and radiation sensitive genes (rad-51 and him-6) were all up-regulated suggesting responses to oxidative stress. The down-regulation of muscle-related genes (mua-3, col-97, col-109, and col-113) maybe due to reduced mechanical stress in muscle exposed to long-term microgravity. This was the longest exposure of a multi-generational cohort of C. elegans to microgravity which were passaged through at least 10 generations in space. The results suggest key changes in genes involved in ageing, DN A repair, oxidative stress and muscle growth
Data on the Lignosus rhinocerotis water soluble sclerotial extract affecting intracellular calcium level in rat dorsal root ganglion cells
The data in this article contain supporting evidence for the research manuscript entitled “Bronchodilator effects of Lignosus rhinocerotis extract on rat isolated airways is linked to the blockage of calcium entry” by Lee et al. (2018) [1]. The data were obtained by calcium imaging technique with fluorescent calcium indicator dyes, Fura 2-AM, to visualize calcium ion movement in the rat dorsal ganglion (DRG) cells. The effects of L. rhinocerotis cold water extract (CWE1) on intracellular calcium levels in the DRG cells were presented. Keywords: Lignosus rhinocerotis, Medicinal mushroom, Bronchodilators, Calcium dynamic
Gamma-tocotrienol acts as a BH3 mimetic to induce apoptosis in neuroblastoma SH-SY5Y cells
Bcl-2 family proteins are crucial regulators of apoptosis. Both pro- and antiapoptotic members exist, and overexpression of the latter facilitates evasion of apoptosis in many cancer types. Bcl-2 homology domain 3 (BH3) mimetics are small molecule inhibitors of antiapoptotic Bcl-2 family members, and these inhibitors are promising anticancer agents. In this study, we report that gamma-tocotrienol (γT3), an isomer of vitamin E, can inhibit Bcl-2 to induce apoptosis. We demonstrate that γT3 induces cell death in human neuroblastoma SH-SY5Y cells by depolarising the mitochondrial membrane potential, enabling release of cytochrome c to the cytosol and increasing the activities of caspases-9 and -3. Treatment of cells with inhibitors of Bax or caspase-9 attenuated the cell death induced by γT3. Simulated docking analysis suggested that γT3 binds at the hydrophobic groove of Bcl-2, while a binding assay showed that γT3 competed with a fluorescent probe to bind at the hydrophobic groove. Our data suggest that γT3 mimics the action of BH3-only protein by binding to the hydrophobic groove of Bcl-2 and inducing apoptosis via the intrinsic pathway in a Bax- and caspase-9-dependent manner
Implementing HLA-B*58:01 testing prior to allopurinol initiation in Malaysian primary care setting: A qualitative study from doctors’ and patients’ perspective
IntroductionAllopurinol, the first-line treatment for chronic gout, is a common causative drug for severe cutaneous adverse reactions (SCAR). HLA-B*58:01 allele was strongly associated with allopurinol-induced SCAR in Asian countries such as Taiwan, Japan, Thailand and Malaysia. HLA-B*58:01 screening before allopurinol initiation is conditionally recommended in the Southeast-Asian population, but the uptake of this screening is slow in primary care settings, including Malaysia. This study aimed to explore the views and experiences of primary care doctors and patients with gout on implementing HLA-B*58:01 testing in Malaysia as part of a more extensive study exploring the feasibility of implementing it routinely.MethodsThis qualitative study used in-depth interviews and focus group discussions to obtain information from patients with gout under follow-up in primary care and doctors who cared for them. Patients and doctors shared their gout management experiences and views on implementing HLA-B*58:01 screening in primary care. Data were coded and analysed using thematic analysis.Results18 patients and 18 doctors from three different healthcare settings (university hospital, public health clinics, private general practitioner clinics) participated. The acceptability to HLA-B*58:01 screening was good among the doctors and patients. We discovered inadequate disclosure of severe side effects of allopurinol by doctors due to concerns about medication refusal by patients, which could potentially be improved by introducing HLA-B*58:01 testing. Barriers to implementation included out-of-pocket costs for patients, the cost-effectiveness of this implementation, lack of established alternative treatment pathway besides allopurinol, counselling burden and concern about genetic data security. Our participants preferred targeted screening for high-risk populations instead of universal screening.ConclusionImplementing HLA-B*58:01 testing in primary care is potentially feasible if a cost-effective, targeted screening policy on high-risk groups can be developed. A clear treatment pathway for patients who test positive should be made available
Preliminary study shows novel variant detected in the screening of RET gene in Malaysian patients with Hirschsprung’s disease
Hirschsprung’s disease (HSCR) is a disorder associated with congenital absence of ganglion cells in the gastrointestinal tract. Molecular analyses have identified variants in various genes including RET, GDNF, EDN3 and EDNRB that are involved in the development, migration and survival of neural cells. Variants in the receptor tyrosine kinase (RET) are most common and have been identified in 10-20% of sporadic HSCR patients. The objective of this study was to screen for RET gene variants in Malaysian patients with HSCR. Thirty-two patients with HSCR and 30 normal controls were recruited for this study. Mutations were screened using the Polymerase Chain Reaction – Denaturing High Performance Liquid Chromatography (PCR-dHPLC) approach. Mutations identified were then confirmed using Sanger sequencing. We identified one novel rare variant in exon 4 (A268A c807 G>C) in one patient. We also identified the common coding sequence variantsA45A (c135G>A), A432A (c1296A>G), L769L (c2307 T>G) and the G691S in our cohort of patients. In conclusion, our Malaysian patients with HSCR diseases showed the presence of similar RET gene common variants which have been described in other populations. We have also identified a novel variant in exon 4 (A268A)