Biomedical subjects

Kang-Duk Choi

Publications and source records attributed to Kang-Duk Choi.

4 recordsLinked to original sources

PubMed2006

A water extract of Artemisia capillaris prevents 2,2'-azobis(2-amidinopropane) dihydrochloride-induced liver damage in rats.

A water extract of Artemisia capillaris Thunberg (Compositae) was investigated for protective effects against oxidative stress induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) in Sprague-Dawley male rats. Rats were orally administered A. capillaris water extract (ACWE; 7.5 g/kg) for 7 days before AAPH treatment (60 mg/kg). AAPH intoxication significantly elevated enzyme markers of liver injury (glutamic oxaloacetic transaminase and glutamic pyruvic transaminase). The pre-administration of ACWE significantly reduced the liver-damaging effects of AAPH as indicated by the low levels of these enzymes. Moreover, the ACWE administration significantly attenuated the accumulation of thiobarbituric acid-reactive substances in both plasma and liver tissues compared with those of rats administered AAPH alone. Furthermore, ACWE administration slightly improved the liver reduced glutathione levels and enhanced the production of antioxidant enzymes like catalase. A. capillaris contained 10.1 mg of catechin in 100 g of dried sample; the high-performance liquid chromatography results showed catechin composition in the ACWE to be 28% (-)-epigallocatechin gallate, 49% (-)- epigallocatechin, and 23% other catechins. These observations clearly indicate that ACWE contains antioxidant catechins capable of ameliorating the AAPH-induced hepatic injury by virtue of its antioxidant activity.

Alanine Transaminase↗

PubMed2005

Gene expression profiling in hypothalamus of immobilization-stressed mouse using cDNA microarray.

To investigate the effects of repeated immobilization-stress challenge on HPA axis, genomic transcriptome in the hypothalamus of immobilization-stressed mouse was analyzed by using cDNA microarray. With the 1.5-fold cutoff of arbitrary criteria, the expression levels of 108 genes out of 6016 genes were significantly modulated in the hypothalamus by the stress. Energy metabolism-, lipid metabolism-, and apoptosis- and signal transduction-related genes were activated while DNA repair-, protein biosynthesis-, and structure integrity-related genes were down-regulated in the hypothalamus. Eighteen genes among them were selected for RT-PCR analysis to confirm the change of their expression levels on agarose gels. Besides, dozens of novel genes, which have not been previously reported, were screened to be modulated by the immobilization stress through the transcriptome analysis. These genes are related to apoptosis, tumor-suppression, DNA-binding and protein folding, and thus may be used as potential targets for the development of therapeutics of chronic stress or depressant.

Animals↗

PubMed2004

Association of IL-1beta, IL-1ra, and TNF-alpha gene polymorphisms in childhood nephrotic syndrome.

We investigated the association between IL-1beta, IL-1ra, and TNF-alpha gene polymorphisms and childhood nephrotic syndrome (NS). We analyzed the genetic polymorphism of IL-1beta, IL-1ra, and TNF-alpha genes in 152 patients with childhood NS and 292 healthy adult controls. The C to T exchange at position -511 of IL-1beta and the G to A at -308 of the TNF-alpha gene were genotyped. Five alleles of the IL-1ra gene were identified and designated as IL1RN*1, IL1RN*2, IL1RN*3, IL1RN*4, and IL1RN*5, according to the variable number of tandem repeats in intron 2. The allele frequencies of IL-1beta1 (-511C), IL-1beta2 (-511T), TNF1 (-308G), and TNF2 (-308A) were 53.0, 47.0, 92.1, and 7.9%, respectively, in the childhood NS group. This was not significantly different from normal controls. In the childhood NS group, the allele frequencies of IL1RN*1, IL1RN*2, IL1RN*3, IL1RN*4, and IL1RN*5 were 90.8, 7.6, 1.6, 0, and 0% [IL1RN*1 odds ratio (OR)=0.296, P=0.0001, IL1RN*2 OR=3.902, P=0.0002]. A high allele frequency of IL1RN*2 and a lower allele frequency of IL1RN*1 were found in childhood NS, although there was no association with IL-1beta and TNF-alpha. A high allele frequency of the IL1RN*2 allele may affect disease susceptibility in childhood NS.

Adult↗

PubMed2003

Apolipoprotein E polymorphism and clinical course in childhood nephrotic syndrome.

Numerous studies have reported on the role of apolipoprotein E (apoE) polymorphism in the progression of diseases associated with lipid abnormalities. However, few studies have been performed to date on the relationship between apoE polymorphism and childhood nephrotic syndrome (NS). In the present study, we evaluated the allelic and genotypic frequencies of the apoE gene and the possible association between the polymorphic forms of the apoE gene on the clinical course in 190 patients with childhood NS, who were further classified into frequent relapsers (FR, 92) and nonrelapsers or infrequent relapsers (IR, 98). Controls included 132 healthy Koreans. Allele-specific primers were used to detect polymorphism of the apoE gene. The allelic frequencies at the apoE locus were 5.9%, 82.6%, and 11.8% for alleles epsilon2, epsilon3, and epsilon4, respectively in the childhood NS group, while those in the control group were 6.8% for epsilon2, 88.3% for epsilon3, and 4.9% for epsilon4. The allelic frequency for epsilon4 in childhood NS was twice that of controls. Moreover, the allelic frequency of the epsilon4 allele in the FR group was 3.4 times that of the control group and 2.5 times that of the IR group. The high frequency of epsilon4 in patients with childhood NS suggests that epsilon4 may serve as a genetic marker for predisposition to childhood NS. We believe that the apoE allele type is of considerable significance in predicting the course of the disease.

Adolescent↗