• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.5
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• pp.493-499
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• 2019

Thiamine (vitamin $B_1$) is a water-soluble vitamin that is not endogenously synthesized in humans. It is absorbed by the small intestine, where it is activated. Its active form acts as a coenzyme in many energy pathways. We report a rare case of thiamine deficiency in a 3.5-year old boy with short bowel syndrome secondary to extensive bowel resection due to necrotizing enterocolitis during his neonatal age. The patient was parenteral nutrition-dependent since birth and had suffered from recurrent central catheter-related bloodstream infections. He developed confusion with disorientation and unsteady gait as well as profound strabismus due to bilateral paresis of the abductor muscle. Based on these and a very low thiamine level he was diagnosed and treated for Wernicke encephalopathy due to incomplete thiamine acquisition despite adequate administration. He fully recovered after thiamine administration. After 1999 eight more cases have been reported in the PubMed mostly of iatrogenic origin.

• Journal of Genetic Medicine
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• v.16 no.1
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• pp.31-38
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• 2019

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a maternally inherited mitochondrial disorder of which m.3243A>G is the most commonly associated mutation, resulting in an inability to meet the energy requirements of various organs. MELAS poses a diagnostic challenge owing to its multiple organ involvement and great clinical variability due to its heteroplasmic nature. We report three cases from a family who were initially misdiagnosed with myasthenia gravis or undiagnosed. Although there is no optimal consensus treatment approach for patients with MELAS because of the disease's heterogeneity, our 21-year-long therapy regimen of ${\text\tiny{L}}-arginine$, ${\text\tiny{L}}-carnitine$, and coenzyme Q10 supplementation combined with dietary management appeared to provide noticeable protection from the symptoms and complications. Prompt early diagnosis is important, as optimal multidisciplinary management and early intervention may improve outcomes.

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.206-212
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• 1999

The gene orf7(oxi III) was expressed using an E. coli system in anticipation that it would encode dTDP-glucose 4,6-dehydratase which is involved in the biosynthesis of the olivose moiety of chlorothricin produced from Streptomyces antibioticus Tu99. The solubility of the expressed protein increased up to 20% under optimal induction conditions. The expressed protein was purified from the E. coli BL 21(DE3) cell lysate by a 28.5-fold purification in two chromatography steps with a 38% recovery to near homogeneity. The molecular weight and N-terminal amino acid sequence of the purified protein correlated with the predicted mass and sequence deduced from the orf7 gene. The purified protein was a homodimer with a subunit relative molecular weight of 38,000 Dalton. The expressed protein was found to exhibit dTDP-glucose 4,6-dehydratase activity and be highly specific for dTDP-glucose as a substrate. The values of K'm and V'max for dTDP-glucose were 28 $\mu$M and 295 nmol $min^{-1} (mg protein)^{-1}$, respectively. dTTP and dTDP were strong inhibitors of this enzyme.$NAD^+$, the coenzyme for dTDP-glucose 4,6-dehydratase, was tightly bound to the expressed protein.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.526-534
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• 2013

This study was conducted to examine the effects of Opuntia ficus-indica complex (OF) on the lipid metabolism, bile acid in feces, alanine aminotransferase (ALT) activity, aspatate aminotransferase (AST) activity, composition of urine and expression of cholesterol related mRNA in streptozotocin (STZ)-induced diabetic rats. Thirty two male Sprague-Dawley rats were randomly divided into non-diabetic control (NC), diabetic control (DC), diabetic OF of 2% (OF-2) and diabetic OF of 5% (OF-5), then each group was fed for 3 weeks. Plasma total cholesterol, non-esterified fatty acids (NEFA), total cholesterol, low density lipoprotein (LDL), very low density lipoprotein (VLDL) were decreased significantly (p<0.05) in OF-5 group compared to DC, but high density lipoprotein (HDL) was not changed. AST and ALT were also reduced and bile acid excretion was improved. Composition of urine in OF-5 was almost same in NC. The expression of cholesterol $7{\alpha}$-hydroxylase (CYP7A1), 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA-R), Low density lipoprotein receptor (LDL-R) mRNA indicated that feeding OF have the effects of cholesterol decreation in plasma by synthesis of bile acid from cholesterol. These results provide experimental evidence about improved lipid metabolism of the OF feeding in the STZ-induced diabetic rats.

• YAKHAK HOEJI
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• v.57 no.6
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• pp.388-393
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• 2013

Previously, we have reported that lovastatin, an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, increased melanin synthesis through intracellular $Ca^{2+}$ release in B16 cells. In this study we investigated the possible involvement of nitric oxide (NO) in the mechanism of lovastatin-induced melanogenesis. Lovastatin elevated NO formation in a dose-dependent manner. Treatment with mevalonate, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), precursors of cholesterol, did not significantly alter the lovastatin-induced NO production, suggesting that inhibition of cholesterol metabolism may not be involved in the mechanism of this action of lovastatin. Both NO formation and melanogenesis induced by lovastatin was significantly suppressed by treatment with $N^G$-nitro-L-arginine methyl ester (L-NAME) and 2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylinidazoline-1-oxyl-3-oxide (cPTIO), an inhibitor of NO synthase and a NO scavenger, respectively. The lovastatin-induced NO production was significantly affected not by EGTA, an extracellular $Ca^{2+}$ chelator, but by an intracellular $Ca^{2+}$ chelator (BAPTA/AM) and intracellular $Ca^{2+}$ release blockers (dantrolene and TMB-8). Taken together, these results suggest that lovastatin may induce melanogenesis through NO formation mediated by intracellular $Ca^{2+}$ release in B16 cells. These results further suggest that lovastatin may be a good candidate for the therapeutic application of various hypopigmentation disorders.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.222-227
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• 2002

Squalene synthase catalyzes the reductive dimerization of two molecules of farnesyl diphosphate to form squalene at the final branch point of the cholesterol biosynthetic pathway. Due to the unique position of this enzyme in the pathway, its inhibitors may have advantages as antihypercholesterolemic agents. Therefore, selective inhibitors of squalene synthase do not prevent the formation of the essential branch products of the isoprene pathway, such as dolichol, coenzyme-Q, and prenylated proteins, as might be expected for inhibitors of enzymes earlier in the pathway; for example, lovastatin and mevalotin. The current study reports that CJ90002, a pentagalloylglucose isolated from Paeonia moutan SIM (Paeoniaceae), which is an important Chinese crude drug used in many traditional prescriptions, was a potent inhibitor of rat microsomal squalene synthase, and also a potent inhibitor of cholesterol biosynthesis in vitro. In addition, the intraperitoneal and oral administration of CJ90002 had a significant lowering effect on plasma cholesterol levels in hamsters.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.1
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• pp.37-45
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• 2019

To study the effect of nicorandil pretreatment on ketone body metabolism and Acetyl-CoA acetyltransferase (ACAT1) activity in hypoxia/reoxygenation (H/R)-induced cardiomyocytes. In our study, we applied H9c2 cardiomyocytes cell line to evaluate the cardioprotective effects of nicorandil. We detected mitochondrial viability, cellular apoptosis, reactive oxygen species (ROS) production and calcium overloading in H9c2 cells that exposed to H/R-induced cytotoxicity. Then we evaluated whether nicorandil possibly regulated ketone body, mainly ${\beta}$-hydroxybutyrate (BHB) and acetoacetate (ACAC), metabolism by regulating ACAT1 and Succinyl-CoA:3-ketoacid coenzyme A transferase 1 (OXCT1) protein and gene expressions. Nicorandil protected H9c2 cardiomyocytes against H/R-induced cytotoxicity dose-dependently by mitochondria-mediated anti-apoptosis pathway. Nicorandil significantly decreased cellular apoptotic rate and enhanced the ratio of Bcl-2/Bax expressions. Further, nicorandil decreased the production of ROS and alleviated calcium overloading in H/R-induced H9c2 cells. In crucial, nicorandil upregulated ACAT1 and OXCT1 protein expressions and either of their gene expressions, contributing to increased production of cellular BHB and ACAC. Nicorandil alleviated cardiomyocytes H/R-induced cytotoxicity through upregulating ACAT1/OXCT1 activity and ketone body metabolism, which might be a potential mechanism for emerging study of nicorandil and other $K_{ATP}$ channel openers.

• Journal of Life Science
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• v.20 no.2
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• pp.190-196
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• 2010

Nowadays many people use antibiotics to protect processed foods from many pathogenic bacteria. The abuse of antibiotics, however, can run the risk of creating resistant forms of bacterium. Our study focus is on making new substances that can not only replace antibiotics but also be friendly to the environment. In our experiments, we used fermented citrus fruit, soil microbes and coenzyme Q10 as probiotics and prebiotics. Chickens in the experimental group were fed these substances via oral route while those in the control group were not. After specific time periods, blood and feces samples were collected to test for Salmonella spp.. It is interesting that fermented citrus fruit was the most effective in suppressing this bacterium. Furthermore, dissection of the experiment group chickens shows that their livers did not change to a yellow color, in contrast to the control group. The results confirmed our proposal that the chickens fed with these materials can be protected from infection by Salmonella and other pathogens. These probiotics and prebiotics are highly practical because they are natural substances that can be easily recycled in the environment. It can also be used as an animal feed ingredient because of its safety.

• Journal of Nutrition and Health
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• v.32 no.6
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• pp.654-660
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• 1999

Folate, a precursor of the coenzyme tetrahydrofolate, plays an important role in DNA replication and cell proliferation, and thus could influence rapidly proliferating immune cells such as leukocytes and splenocytes. The effects of dietary folate on folate concentrations of plasma, thymus, spleen and leukocytes were investigated in rats. The animals were raised for 6 weeks on semipurifed experimental diets containing 0mg, 2mg, 4mg, 8mg folate/kg diet. Folate concentrations were determined microbiologically using Lactobacillus casei(ATCC 7469), and DNA strand breaks produced by alkaline treatment were analyzed fluorometrically. When compared to folate adequate diet, the folate deficient diet(0mg folate/kg diet) resulted in lowest folate levels in plasma, thymus, spleen and leukocytes, and the highest DNA strand breaks in spleen cells and leukocytes. Dietary folate levels significantly increased folate concentrations of immune tissues, leukocytes, and the plasma in a dose dependent manner, folate concentrations being highest with a diet providing 8mg folate/kg diet. The percentages of the double strand DNA remaining in the splenocytes and leukocytes after alkaline treatment were significantly increased with higher amounts of dietary folate in a dose dependent manner. Folate intakes of 8mg than 4mg/kg diet was found to be more effective in the prevention of DNA strand breaks. The results of this study suggest that increased folate above the requirement level could improve DNA stabilities in immune cells.

• Journal of Photoscience
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• v.7 no.2
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• pp.73-78
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• 2000

To analyze molecular traits determining pigmentation between Pharbitis nill violet and white, Amplified Fragment Length Polymorphism(AFLP) and Differential Display Reverse Transcription(DDRT) experiments were carried out with either genomic DNAs or total RNAs isolated from both plants. Results of AFLP experiment in combination of 8 EcoRⅠ primers with 6 MseⅠ primers showed 41 violet-and 60 white-specific DNA bands. In the subsequent experiment, 22 violet-and 22 white-specific DNA fragments were amplified by PCR with DNAs eluted. The sizes of the fragments range from 200 to 600bp. DDRT using total RNA produced 19 violet-and 17 white-specific cDNA fragments, ranging from 200 to 600bp. The fragments obtained by both AFLP and DDRT had been cloned into pGEM T-easy vector, amplified and subjected to the nucleotide sequence analyses. As a result of Blast sequence analysis, most of them sequenced up to date showed no similarity to any Known gene, while few has similarity to known animal or plant genes. An AFLP clone V6, for example, has a strong sequence similarity to the human transcription factor LZIP-alpha mRNA and a DDRT clone W19 to Solanum tuberosum 3-hydroxy-3-methylglutaryl coenzyme A reductase mRNA.