• Applied Biological Chemistry
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• v.38 no.4
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• pp.320-324
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• 1995

Solubilization of microsomal ${\Delta}^{5}-3{\beta}$-hydroxy steroid acyl transfearse(${\Delta}^{5}-3{\beta}$-OH-SAT) of rat brain and its reconstitution into liposomes were investigated. Among the detergents utilized for the solubilization, deoxycholic acid was superior to Tween 80 or Triton X-100 for the reconstituted activity of ${\Delta}^{5}-3{\beta}$-OH-SAT. The enzyme activity was shown to be affected by the nature of phospholipids used for the preparation of the liposome. Phosphatidylcholines from egg yolk and soybean showed the highest activity of ${\Delta}^{5}-3{\beta}$-OH-SAT and phosphatidylethanolamine came next. However phosphatidylserine and phosphatidic acid showed a lower activity than those obtained before the reconstitution. This study suggests that the presence of quaternary ammonium salt or amine group in the phospholipids stimulates the activity of ${\Delta}^{5}-3{\beta}$-OH-SAT. However the presence of a carboxylic group or the absence of the amine group may have an inhibitory effect on the ${\Delta}^{5}-3{\beta}$-OH SAT.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.254-259
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• 1996

The biochemical factors responsible for parathion resistance in a ethyl fenitrothion-selected Yumenoshima I11 (EF-30) strain of the housefly were examined. Great difference (167-fold) in the Iso was observed between the resistant EF-30 (R) and susceptible SRS (S) strains in vitro, suggesting that altered acetylcholinesterase (AChE) in the housefly strain was an important factor in the resistance. The in vitro degradative activity of parathion and paraoxon in both strains was associated with the microsomal and soluble fractions and required NADPH and reduced glutahione (GSH), respectively. The R strain possessed higher activity for GSH S-transferase than the S strain, and this enzyme appears to be important in the resistance mechanism. The R strain was highly resistant to parathion (101,487-fold), but substitution of the methoxy group for ethoxy group decreased the resistance level (25,914-fold) and parathion could be a substrate of GSH S-transferase. It is concluded that the combination of some factors (altered AChE, and enhanced activity of cytochrome P450 dependent monooxygenase and GSH S-transferase) could be sufficient to account for the extremely high level of resistance to parathion and parathion-methyl, although a possible involvement of other factor(s) can not be excluded.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3335-3340
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• 2016

Background: Oral submucous fibrosis (OSF) is a precancerous condition with a 4 to13% malignant transformation rate. Related to the habit of areca nut chewing it is mainly prevalent in South-east Asian countries where the habit of betel quid chewing is frequently practised. On chewing, alkaloids and polyphenols are released which undergo nitrosation and give rise to N-nitrosamines which are cytotoxic agents. CYP450 is a microsomal enzyme group which metabolizes various endogenous and exogenous chemicals including those released by areca nut chewing. CYP1A1 plays a central role in metabolic activation of these xenobiotics, whereas CYP2E1 metabolizes nitrosamines and tannins. Polymorphisms in genes that code for these enzymes may alter their expression or function and may therefore affect an individuals susceptibility regarding OSF and oral cancer. The present study was therefore undertaken to investigate the association of polymorphisms in CYP1A1 m2 and CYP2E1 (RsaI/PstI) sites with risk of OSF among areca nut chewers in the Northern India population. A total of 95 histopathologically confirmed cases of OSF with history of areca nut chewing not less than 1 year and 80, age and sex matched controls without any clinical signs and symptoms of OSF with areca nut chewing habit not less than 1 year were enrolled. DNA was extracted from peripheral blood samples and polymorphisms were analyzed by PCR-RFLP method. Gene polymorphism of CYP1A1 at NcoI site was observed to be significantly higher (p = 0.016) in cases of OSF when compared to controls. Association of CYP1A1 gene polymorphism at NcoI site and the risk of OSF (Odd's Ratio = 2.275) was also observed to be significant. However, no such association was observed for the CYP2E1 gene polymorphism (Odd's Ratio = 0.815). Our results suggest that the CYP1A1 gene polymorphism at the NcoI site confers an increased risk for OSF.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.269-276
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• 1988

식이성 아연이 에탄올의 생체대사율에 미치는 영향을 검토코저 흰쥐에 식이중 아연의 함량(100ppm, 5ppm)을 달리하여 성장시키면서 에탄올을 4주 및 7주간 급여한 다음, 체중증가량과 에탄올의 대사에 관여한다고 알려져 있는 alcohol dehydrogenase, microsomal ethanol oxidizing system, catalase 및 aldehyde dehydrogenase의 활성변동과 혈중 에탄올 제거율을 측정한 결과는 다음과 같다. 실험기간 중 체중증가량은 대조군에 비해 Zn이 부족한 실험군에서 감소되었으며, 에탄올을 투여한 CE군과 ZnDE군은 control에 비해 현저히 감소하였다. Zn 부족한 군(ZnD)에서의 간 ADH, MEOS의 활성 및 혈액중 에탄올 제거율이 아연이 충분히 함유된 대조군에 비해 감소하였으나, catalase와 AIDH의 활성은 별다른 차이를 관찰할 수 없었다. 한편 에탄올을 투여한 CE 및 ZnDE군에서는 대조군(C 및 ZnD)에 비하여 ADH, MEOS 및 혈액중 에탄올 제거율이 증가하였으며 그 증가율은 아연을 충분히 급여한 CE군에서 아연이 부족한 ZnDE 군에 비하여 높게 나타났다. AIDH의 활성은 에탄올의 투여에 의해 CE군에서는 증가하였으나 ZnDE군에서는 별다른 변동을 관찰할 수 없었으며 catalase의 활성은 전실험군에 있어서 차이를 발견할 수 없었다.

• Journal of Nutrition and Health
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• v.39 no.2
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• pp.91-99
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• 2006

This study was conducted to investigate the effects of mulberry fruit, mulberry leaves and silkworm powder with different mixing ratios on hepatic antioxidative system and lipid metabolism in streptozotocin-induced diabetic rats. Sprague-Dawley male rats weighing $100{\pm}10g$ were induced diabetic by 50 mg/kg bw streptozotocin and randomly assigned to following experimental groups; normal diet group (DM), 0.3% and 0.6% mulberry fruit diet groups (F and 2F), 0.3% mulberry leaves diet group (M), 0.3% silkworm powder diet group (S), 0.15% mulberry fruit+0.15% mulberry leaves diet group (FM), 0.15% mulberry fruit+0.15% silkworm powder diet group (FS), 0.1 % mulberry fruit+0.1 % mulberry leaves+0.1% silkworm powder diet group (FMS). The experimental diets were fed for 4 weeks. Hepatic SOD activity was not changed significantly by any of single or combined supplementations of mulberry fruit, leaves and silkworm powder but GSH-px and catalase activities were increased by the groups supplemented with two or three of the test ingredients (FM, FS, FMS) as compared with the DM group. Hepatic TBARS value was not reduced significantly by any of the supplementations but lipofuscin contents were significantly reduced in the FM, FS and FMS groups as compared with the DM group. Hepatic mitochondria and microsomal carbonyl values were reduced by the single and combined supplementations of the test ingredients. Hepatic HMG-CoA reductase activities were increased in the all supplementation groups as compared with the DM group. Hepatic total lipid and triglyceride contents were increased but cholesterol contents reduced in the supplemented groups. The effects on the enzyme activities, peroxide or its products and lipid contents were most remarkable in the FMS group. In conclusion, mulberry fruit, mulberry leaves and silkworm powder have the favorable effects on antioxidative system and lipid metabolism in the diabetic liver and the mulberry fruit, leaves and silkworm powder with equal ratio exert the synergistic effect expectedly to prevent diabetic complications.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.111-120
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• 1991

In order to investigate the cellular peroxidative damage due to heated oil intake and the preventive effect of vitamin E on it rats were fed heated corn oil with acid value of 4.02 at the level of 10 Cal% and three different levels of vitamin E that were 0, 40 and 200 mg/kg diet. Control group was fed fresh corn oil and 40mg/kg diet of vitamin E. After ech feeding period of 0, 3 and 6 weeks, liver superoxide dismutase (SOD), glutathione peroxidase (GPX) activities and microsomal content of vitamin E and lipid peroxide (LPO) were measured as well as cellular morphology was examined. SOD activities and LPO contents were higher, while GPX activities and vitamin e contents were lower in heated oil groups than control group. Electromicroscopic observation revealed the loss of inner mitochondrial membrane and cristae and irregular arrangement of nuclear membrane and chromatin in heated oil groups. As dietary vitamin e level was increased, SOD activity and LPO content were decreased, but GPX activity and vitamin E content in the liver increased and cellular peroxidative damage reduced progressively. This phenomena was more remarkable in 6 weeks of feeding than 3 weeks.

• Journal of Food Hygiene and Safety
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• v.34 no.4
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• pp.388-395
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• 2019

The object of the present study was to examine the effect of selenium-treated Spinacia oleracea L. on antioxidative defense system and oxidative damage in rats fed high-fat and high-cholesterol diets. Experimental rats were divided into six groups which were composed of normal diet group (N), high-fat and high-cholesterol diet group (HF), high-fat and high-cholesterol diet with 5% or 10% non-treated spinach supplemented group (SPA or SPB) and high-fat and high-cholesterol diet with 5% or 10% selenium-treated spinach-supplemented group (SSA or SSB). In the antioxidant enzyme activities of hepatic glutathione peroxidase and superoxide dismutase, activities increased in supplementation of non-treated or selenium-treated spinach groups compared to HF group. However, there was no significant difference in the activity of hepatic catalase among all experimental groups. The microsomal superoxide radical content of the SSB group was significantly reduced compared to the HF group. The mitochondrial carbonyl values of the SSB group were significantly reduced compared to the HF group. Thiobarbituric acid reaction substance (TBARS) values in RBC and liver were also reduced in non-treated or selenium-treated spinach-supplemented groups compared to the HF group. The hepatic TBARS values of the supplementation of selenium-treated spinach groups significantly decreased compared to the supplementation of non-treated spinach groups. These results suggest that selenium-treated spinach may reduce oxidative damage by the activation of antioxidative defense system in rats fed high-fat and high-cholesterol diets.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.399-415
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• 1999

From bacteria to mammalian cells, one of the most important mediators of intracellular signal transduction mechanisms which regulate a variety of intracellular processes is free calcium. In salivary acinar cells, elevation of intracellular calcium concentration ($[Ca^{2+}]_i$) is essential for the salivary secretion induced by parasympathetic stimulation. However, in addition to $[Ca^{2+}]_i$, gap junctions which couple individual cells electrically and chemically have also been reported to regulate enzyme secretion in pancreatic acinar cells. Since the plasma membrane of salivary acinar cells has a high density of gap junctions, and these cells are electrically and chemically coupled with each other, gap junctions may modulate the secretory function of salivary glands. In this respect, I planned to investigate the role of gap junctions in the modulation of salivary secretion and $[Ca^{2+}]_i$, using mandibular salivary glands of rats. In order to measure the salivary flow rate, fluid was collected from the cannulated duct of the isolated perfused rat mandibular glands at 2 min intervals. $[Ca^{2+}]_i$, was measured from the cells loaded with fura-2 by spectrofluorometry. The results obtained were as follows: 1. CCh-induced salivary secretion was reversibly inhibited by 1 mM octanol, a gap junction blocker. 2. CCh-induced increase in $[Ca^{2+}]_i$, was also reversed by the application of 1 mM octanol. 3. Octanol did not block the initial increase in $[Ca^{2+}]_i$ caused by CCh, which suggested that the reduction of $[Ca^{2+}]_i$, caused by gap junction blockade was not resulted from the inhibition of $Ca^{2+}$ release from intracellular $Ca^{2+}$ stores. 4. Addition of octanol during stimulation with $1{\mu}M$ thapsigargin, a potent microsomal ATPase inhibitor, reduced $[Ca^{2+}]_i$, to the basal level. This suggested that inhibition of gap junction permeability closed plasma membrane $Ca^{2+}$ channels. 5. 2,5-di-tert-butyl-1,4-benzohydroquinone (TBQ) generated $[Ca^{2+}]_i$ oscillations resulting from periodic influx of $Ca^{2+}$ via plasma membrane. The TBQ-induced $[Ca^{2+}]_i$ oscillations were stopped by the application of 1mM octanol which implicated that gap junctions modulate the permeability of plasma membrane $Ca^{2+}$ channels. 6. Glycyrrhetinic acid, another well known gap junction blocker, also inhibited CCh-induced salivary secretion from rat mandibular glands. These results suggested that gap junctions play an important role in the modulation of fluid secretion from the rat mandibular glands and this was probably due to the inhibition of $Ca^{2+}$ influx through the plasma membrane $Ca^{2+}$ channels.