• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.485-492
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• 1996

myo-Inositol, a growth factor for Saccharomyces cerevisiae (S. cerevisiae), has been known to be incorporated into phosphatidylinositol (PI), which is a kind of phospholipid in the cell membrane, by a membrane-associated PI-synthesizing enzyme. The deficiency of myo-inositol in S. cerevisiae adversely affected the membrane structure and function. On the basis of biochemical functions of myo-inositol, the effect of deficiency of myo-inositol on the aerobic glucose metabolism was investigated by measuring specific oxygen uptake rate (Q$_{O2}$) used as an indicator representing the respiratory capacity of S. cerevisiae in batch and continuous cultures. The respiratory capacity of aerobic glucose metabolism in S. cerevisiae was also monitored after glucose pulse-addition in a continuous culture (D=0.2, 1/hr), in which glucose was utilized through respiratory metabolism. The deficiency of myo-inositol was found to lead to both the decrease of the maximum specific oxygen uptake rate (Q$_{O2max}$) observed from the batch as well as in the continuous culture experiment and the decrease of the respiratory capacity of aerobic glucose metabolism of S. cerevisiae determined from the glucose pulse-addition experiment, in which the glucose flux into respiratory and fermen- tative metabolism was quantitatively analyzed.

• Journal of environmental and Sanitary engineering
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• v.14 no.1
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• pp.88-96
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• 1999

The effect of acute cadmium-neuropathy on phospholipid metabolism in rat sciatic nerve was investigated. An animal model of cadmium neuropathy was induced by feeding diet containing cadmium to Sprague-Dawley rat for two weeks. Four weeks aged Sprague-Dawley rats were divided into four groups : normal control group, 10ppm-cadmium treated group, 100ppm-cadmium treated group, 1000ppm-cadmium treated group, reference drug, myo-inositol-treated group. All rats were sacrificed at the end of two weeks. The rate of incorporation of 2-[3H]myo-inositol into polyphosphinositide was significantly decreased while the rates of incorporation into phospholipid of titratedserine, ethanolamine and choline were unchanged in sciatic nerve obtained from cadmium-treated rat. Continuously the activities of three enzymes concerned with inositol phospholiped metabolism were measured in homogenates of rat sciatic nerves. Cystidine diglyceride transferase and phophatidylinositol kinase showed significantly decreased activities while phosphatidylinositol-4-phosphate kinase did not show any significant change in activity by cadmium treatment. However these deficits of inositol phospholipid metabolism were ameliorated by myo-inositol administration and these effectiveness were more potent in lower dose cadmiumtreated rats than higher dose cadmium-treated rats. These results suggest that cadmium intoxicated peripheral nerve with perturbation of the ployphosphoinositide metabolism and alteration of the enzyme activity which concerned with myo-inositol metabolism.

• Journal of environmental and Sanitary engineering
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• v.16 no.4
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• pp.1-8
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• 2001

We have previously demonstrated that sodium molybdate(Mo) improved lead-intoxicated status by enhancing the metabolism of mao-inositol-related phospholipids in sciatic nerves isolated from rats. In this study, in order to address the reduction mechanism of Mo for lead toxicity, effects of Mo on cystidine-diglyceride transferase, phosphatidylinositol kinase, and phosphatidyl inositol-4-phosphate kinase, involved in mao-inositol metabolism of nerve, were investigated in vivo and in vitro. Mo significantly increased the activities of cystidine- diglyceride transferase and phosphatidylinositol kinase in lead-intoxicated rat, and the pattern of increase was dose-dependent manner. However, Mo did not affect the activity of phosp- hatidylinositiol-4-phosphate kinase in normal and lead-intoxicated rats. We also found that Mo affected the activities of phopholipid metabolism-related enzymes not by the indirect manner such as activation of another metabolic pathway but by the direct manner. These results suggest that the improvement mechanism of Mo for lead-intoxicated status might be a normalization of the activities of phospholipid metabolism-related enzymes in sciatic nerve.

• Journal of environmental and Sanitary engineering
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• v.16 no.3
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• pp.14-21
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• 2001

The effects of sodium molybdate(Mo) on phospholipid metabolism in sciatic nerve isolated from lead-intoxicated rat were investigated. Four weeks aged albino rats were divided into four groups : normal control group, lead(10 ppm)-treated group, Mo(1 mg/kg)-treated group, lead and Mo-treated group. As a result of the study, Mo significantly increased the rate of incorporation of $2-[^3H]$myo-inositol into polyphosphinositides in lead-intoxicated rat. Mo also increased the rate of phosphatidylcholine metabolism in normal and lead-intoxicated rats. However, Mo did not affect the metabolism of phosphatidylserine and phosphatidylethanola-mine in normal and lead-intoxicated status. These results suggest that Mo might improve lead-intoxicated status by principally enhancing the metabolism of myo-inositol-related phospholipids and by partly phosphatidylcholine in sciatic nerve.

• Environmental Analysis Health and Toxicology
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• v.9 no.1_2
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• pp.1-8
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• 1994

Nerve conduction impairment in lead neuropathy has been empirically linked to altered nerve myo-inositol metabolism. In most cases of neuropathy, abnormal myo-inositol metabolism is associated with abnormal $Na^+/K^+$ATPase provides a potential mechanism to relate defects of the myo-inositol metabolism in the peripheral nerve treated with lead. Therefore, the effect of lead on the rat sciatic nerve $Na^+/K^+$ATPase and other ATPase of sciatic nerve was studied. ATPase activity was measured enzymatically in sciatic nerve homogenates from 2-wk lead treated neuropathy rats and age-mached controls administered myo-inositol. $Na^+/K^+$ATPase components were assessed by ouabain inhibition or the omission of sodium and potassium ions. Lead reduced 50% reduction in the $Na^+/K^+$ATPase activity in homogenates of sciatic nerve. The 50% reduction in the $Na^+/K^+$ ATPase activity was selectively prevented by myo-inositol treatment. This study suggests that the toxic mechanism of the lead on peripheral nerve may be through reduction in $Na^+/K^+$ATPase activity which has been linked to axonal transport slowing in the rat model of lead neuropathy, via direct changes by the perturbation of the intracelluar sodium or potasium level.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.3310-3316
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• 2011

Hematoxylin is the main component of Hematoxylon campechianum which has been utilized in the southern provinces of Korea as a folk remedy for diabetic complications. In the present study, to investigate the hypoglycemic mechanism of hematoxylin, the 2-deoxyglucose uptake and phospholipid metabolism were examined in sciatic nerves from three groups of rats : normal control, diabetic control, diabetic hematoxylin-treated group. Hematoxylin significantly reduced blood glucose levels in diabetic control rats. On a wet weight basis, the nerves from diabetic rats showed a 20% decrease in total phospholipid from that of controls and a relative decrease in phosphatidylinositide. Hematoxylin treatment increased the incorporation rate of 2-[3H] myo-inositol into total phosphoinositids in diabetic rat. The effectiveness were more potent in higher dose hematoxylin-treated rats than lower dose hematoxylin-treated rats. These results suggest that hematoxylin increases glucose transport and lipid metabolism by partially normalizing concerned with myo-inositol metabolism in diabetic rat. Therefore we propose that hematoxylin can be a promising candidate for diabetes medication.

• Nutritional Sciences
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• v.8 no.3
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• pp.189-195
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• 2005

To assess the effect of pinitol supplementation and strength training for two weeks on the anaerobic capacity during and after exercise, and improvement of glucose metabolism during the recovery period of muscular fatigue with repeated acute bouts of cycling exercise, a total of 24 healthy young men were recruited and randomly and equally divided into three groups; pinitol supplementation group (PSG), placebo group (PLG), and control group (CON). Using a randomized double-blinded design, subjects in PSG were provided pinitol supplement, consumed orally 1.2 g/day, and participated in the resistance exercise program and cycling exercise for two weeks. Subjects in PLG underwent the same protocol as those in PSG but consumed the same amount of placebo. No supplementation and exercise program was given to CON. Before and after the intervention, all subjects were tested for their anaerobic capacities evaluated by Wingate test twice separated by 30 min. During the test, peak anaerobic power (PP), mean anaerobic power, total work, and fatigue index were evaluated During resting and recovery, blood samples were drawn and plasma pinitol, myo-inositol, chiro-inositol, insulin, free fatty acid, glucose, and lactate levels were analyzed After two weeks, PP and relative PP of the second biking were improved from the first biking in PSG only (p<0.05). No changes were found in all other variables of Wingate test in all groups. No statistical differences between groups and pre- and post-intervention were observed in concentrations of pinitol, myo-inositol, and chiro-inositol, but pinitol concentration was higher during recovery compared to the baseline in all groups and testings (p<0.05). Lactate level during recovery was higher than the resting level, but no other blood parameters were significantly changed. In conclusion, two weeks of pinitol supplementation in conjunction with short duration of anaerobic training in healthy young men did not induce any obvious benefits in terms of anaerobic capacity and energy metabolism Individual and/or population susceptibility may be one factor responsible for adopting pinitol supplementation.

• Journal of Embryo Transfer
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• v.16 no.2
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• pp.91-98
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• 2001

We evaluated the effects of the substrate and inhibitors related to phosphatidylinositol metabolism on in vitro maturation and fertilization of porcine oocytes. Cumulus-oocyte complexes were cultured in mTLP-PVA medium supplemented with or without inositol (250 mM) fur 46h. Subsequently, these oocytes were inseminated with fresh boar semen in mTALP-PVA medium for 6h. At 6h after insemination, oocytes were cultured for further 12 h in TCM-199 supplemented with 10% FBS (fetal bovine serum). The higher percentage of oocytes in inositol-supplemented medium reached metaphase of the second meiotic division compared to those in control (81.4% vs. 67.3%; P<0.()5). following 18 h of insemination, more number of male pronuclei were formed in the oocytes matured in inositol-supplemented medium than in those of control experiment (42.0% vs. 27.3%; P<0.05). When oocytes were cultured in medium with 10mM LiCl (chloride lithium) or 0.5mM dbcAMP (dibutyryl cyclic adenosine monophosphate) to determine the role of inositol on the maturation of oocytes, these two drugs inhibited the meiotic division of oocytes (P<0.05). However, addition of inositol to the culture medium did overcome the inhibitory effect of these drugs on the oocyte maturation. DbcAMP and verapamil supplemented synergistically arrested the meiotic division of oocytes. Addition of verapamil did not inhibit germinal vesicle breakdown, but it severly inhibited the second meiotic division of oocytes. These results suggest that inositol exert its improving effects on maturation, by activating the PI (phosphatidylinositol) cycle and causing beneficial changes in both cytoplasm and membrane of oocytes.

• Journal of Life Science
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• v.7 no.2
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• pp.119-126
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• 1997

Phytase(myo-inositol hexkisphosphate phosphohydrolase ; EC 3.1.3.8) was purified from the mucoas of rat intestinal. The molecular weight of enzyme was determined to be 160kDa by sephacryl S-200 gel filtration. Analysis of the purified enzyme o SDS-polyacrylamide gel electrophoresis(SDS-PAGE) showen that it was composed of two different subunits and the molecular weight of its subunit was found to be 70kDa and 90kDa respectively, indicating that this enzyme is hetrodimer. The enzyme activities were activated in the presence of $ MgCl_{2}$, but inhibited by $ZnCl_{2}$, $MnCl_{2}$, and EDTA. The substrates tested, phytase showed the highest affinity for the enzyme at the physiological ph. The Km value for phytic acid(inositol-hexakisphosphate)was 0.31 mM at pH 7.4. rat intestinal mucosa phytase seems to play an important in the metabolism of inositol.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.8-16
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• 1996

Effects of water extract of aloe vera on lead-induced neurotoxicity were investigated in sciatic nerve isolated from rat. The mechanism on toxicity reduction by measuring activities of axonal enzymes, metabolism of myo-inositol in nerve, lead concentration in several organs and so on were further examimed. In the lead-treated rats, the transport rate of axonal enzyme, such as acetyl cholinesterase and choline acetyltransferase, was reduced by from 50% to 30% respectively. Reduction in myo-inositol concentration and $Na^+/K^+$ ATPase activity were also observed in sciatic nerve from lead-treated rat. However, the aloe extract administration significantly eliminated the impairment and maintained myo-inositol concentration to about 85% of normal level. Also aloe extract promoted the excretion rate of lead which is accumulated in blood, sciatic nerve and kidney. These results suggest that lead-induced neurotoxicity was significantly reduced by administration of aloe extract and the mechanism might be partly increase in kidney excretion rate of lead and parity normalization of $Na^+/K^+$ ATPase activity which is critical factor in order to keep nerve maintaining normal myo-inositol level.