t-BHP는 대표적인 산화스트레스에 의한 간 손상 모델이며, 본 연구자는 랫드에 기능성이 강화된 기능성 들깻잎 추출물(P. frutescens leaf extract, PLE)을 250, 500 또는 1000 mg/kg body weight (b.w.)으로 6일간 경구 투여하고 t-BHP의 복강 주사로 간 손상을 일으킨 후 기능성 들깻잎 추출물이 간에서 산화스트레스를 얼마나 억제하여 주는지를 혈액의 간 손상 지표인 lactate dehydrogenase (LDH), aspartate aminotransferase (AST) 그리고 alanine aminotransferase (ALT)를 측정하였으며, 간 조직에서 항산화 바이오 마커인 reduced glutathione (GSH), 지질과산화물의 척도인 malondialdehyde (MDA)를 통해서 측정하였다. 산화스트레스에 의한 간 손상시 GSH는 아무것도 처리하지 않은 정상 대조군(146.0 ± 5.4 mM GSH/g protein)에 비해 t-BHP로 산화스트레스를 유발한 그룹에서 128.6 ± 6.8 mM GSH/g protein로 감소하였다. 반면 기능성 들깻잎 추출물을 250, 500 그리고 1000 mg/kg b.w. 을 투여한 그룹에서는 129.3 ± 2.6 mM GSH/g protein, 151.9 ± 6.8 mM GSH/ g protein, 171.9 ± 5.2 mM GSH/g protein로 농도 의존적으 로 GSH 함량이 회복되는 경향을 나타내며, 500 mg/kg b.w. 투여군부터 정상 대조군의 GSH 함량과 비슷한 수준을 나타내었다. 또한, 간 조직에서 산화스트레스에 의하여 발생된 지질 과산화물을 측정하였을 때 t-BHP에 의하여 산화스트레스만 유발한 그룹은 834.0 ± 154.7 μM/g protein 로 정상 대 조군의 385.6 ± 39.7 μM/g protein 보다 2.17배 높은 MDA 를 생성한 것으로 지질과산화가 많이 일어난 것을 확인하였으나, 기능성 들깻잎 추출물을 투여한 그룹의 MDA의 생성량은 669.2 ± 145.0, 595.1 ± 142.6, 415.9 ± 133.8 μM/g protein 로 농도에 따라 감소하는 경향을 확인하였다. 랫드의 간 조직에서, 독성을 유발하는 t-BHP를 복강 투여 후 기능성 들깻잎 추출물을 경구 투여하였을 때 지질과산화의 지표인 MDA의 감소와 항산화의 지표인 GSH 함량이 증 가하였다. 조직병리학적 확인을 위하여 간 조직을 H&E 염색 후 광학현미경으로 관찰하였을 때, t-BHP만 처리한 음성 대조군의 경우 간 세포의 괴사와 조직의 변형을 확인할 수 있었지만 기능성 들깻잎 추출물을 처리하였을 경우 모두 정상 상태의 조직을 관찰할 수 있었다. 위의 결과들을 종합하였을 때, t-BHP가 간에서 산화스 트레스를 유발하여 간 손상을 야기시키고, 간 조직의 인지질 막 손상을 줄 수 있으며, 기능성 들깻잎 추출물은 간 손상에 대한 보호 효과가 있음을 확인하였다.

Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a unique antioxidant enzyme involved in reduction of peroxidized phospholipids within biomembranes. To investigate the expression pattern of the PHGPx gene during fetal development, in situ hybridization analyses were performed using mouse FITC-labeled PHGPx cRNA probes in fetal tissues on embryonic days (Ed) 13.5-18.5. During these periods, PHGPx mRNA appeared in the developing telencephalon, diencephalon, spinal cord, and spinal ganglion. In particular, PHGPx mRNA was strongly expressed in pyramidal cells of the cerebral cortex. On Eds 17.5-18.5, PHGPx mRNA was detected in various tissues including liver, intestinal villi and crypt, pancreas, lung, and olfactory epithelium of the nasal cavity. In addition, PHGPx mRNA was highly expressed in the inner ear on Eds 14.5-18.5, brown fat on Ed 17.5, and adrenal gland on Ed 18.5. It is conceivable that PHGPx may act as an important antioxidant against fetal oxidative stress during mouse organogenesis.

Phospholipid-hydroperoxide glutathione peroxide (PHGPx) is an antioxidant enzyme that reduces lipid hydroperoxides in biomembranes. Here, we cloned and characterized cys-PHGPx from the bumblebee Bombus ignitus (Bi-PHGPx). The Bi-PHGPx gene consists of 4 exons, encoding 168 amino acid residues with a canonical cys-codon at residue 45 and active site residues Gln82 and Trp134. Recombinant Bi-PHGPx, expressed as a 19 kDa protein in baculovirus-infected insect cells, exhibited enzymatic activity against PLPC-OOH and H2O2 using glutathione as an electron donor. Tissue distribution analyses showed the presence of Bi-PHGPx in all tissues examined. Bi-PHGPx transcripts were upregulated by stresses, such as wounding, H2O2 exposure, external temperature shock, and starvation. Under H2O2 overload, the RNA interference (RNAi)-induced thioredoxin peroxidase (BiTPx1)-knock-down B. ignitus worker bees showed upregulated expression of Bi-PHGPx in the fat body. These results indicate that Bi-PHGPx is a stress-inducible antioxidant enzyme that acts on phospholipid hydroperoxide and H2O2.

An extract of Allomyrina dichotoma larva (ADL), one of the insects used most frequently in traditional Chinese medicine for the treatment of liver diseases such as hepatocirrhosis and hepatofibrosis, was assessed for antioxidant bioactivity in this study.

Reactive oxygen species (ROS) are toxic agents that may be involved in various neurodegenerative diseases. Recent studies indicate that ROS can act as modulators of neuronal activity, and are critically involved in persistent pain primarily through spinal mechanisms. In the present study, whole cell patch clamp recordings were carried out to investigate the effects of tert-buthyl hydroperoxide (t-BuOOH), an ROS, on neuronal excitability and the mechanisms underlying changes of membrane excitability. In current clamp condition, application of t-BuOOH caused a reversible membrane depolarization and firing activity in substantia gelatinosa (SG) neurons. When slices were pretreated with phenyl-N-tert-buthylnitrone (PBN) and ascorbate, ROS scavengers, t-BuOOH failed to induce membrane depolarization. However, isoascorbate did not prevent t-BuOOH-induced depolarization, suggesting that the site of ROS action is intracellular. The t-BuOOH-induced depolarization was not blocked by pretreatment with dithiothreitol (DTT), a sulfhydryl-reducing agent. The membrane-impermeant thiol oxidant 5,5-dithiobis 2-nitrobenzoic acid (DTNB) failed to induce membrane depolarization, suggesting that the changes of neuronal excitability by t-BuOOH are not caused by the modification of extrathiol group. The t-BuOOH-induced depolarization was suppressed by the phospholipase C (PLC) blocker U-73122 and inositol triphosphate (IP₃)receptor antagonist 2-aminoethoxydiphenylbolate (APB), and after depletion of intracellular Cα²+ pool by thapsigargin. These data suggest that ROS generated by peripheral nerve injury can induce central sensitization in spinal cord, and t-BuOOH-induced depolarization may be regulated by intracellular Cα²+ store mainly via PLC-IP₃pathway.

본 연구는 정자 내의 phsopholipid hydroxide glutathion peroxidase (PHGPx) mRNA 발현 수준, heparin-binding protein (HBP) mRNA 발현 수준, 수태율 그리고 산자수 사이의 관계를 조사하고자 실시하였다. 수태율과 산자수 사이에 있어서 상관관계는 나타나지 않았다. PHGPx mRNA 발현 수준에 있어 산자수가 10두 이상 군에서 (2,414.7±400.7) 8두 미만 군보다 (1,875.8±311.2) 높게 나타났으나 유의적인 차이는 없었다. HBP mRNA 발현 수준에 있어서도 산자수 10두 이상 군에서 (2,255.9±360.8) 8두 미만 군보다 (2,155.4±378.0) 약간 높은 결과를 보였으나, 유의적인 차이는 인정되지 않았다. PHGPx mRNA 발현 수준과 산자수 사이의 관계는 (r=0.206) 정의 상관관계를 보였으나, 유의한 상관관계는 나타나지 않았다. 본 실험의 결과, PHGPx와 HBP의 발현수준이 수태율, 산자수와 유의한 상관관계를 보이지 않았기 때문에 PHGPx와 HBP가 정자의 수정능력을 예측하기에는 미흡한 면이 있다.

In the June, 1991, there was the explosion in which methanol rectified column as a part of the new surface active agent's manufacturing processes. The type of explosion was estimated as the 'detonation'. The methanol rectified column was ruined, and broken pieces of the column were scattered within 900m. Also, there were victims such as the two deads and thirteen wounded persons. The cause of the explosion was heat explosion by being concentrated locally from 0.1% to several tens% of supply fluid at Metal Hydroperoxide, which was produced by methanol and hydrogen peroxide used as the bleach of surface active agent, during the operation stoppage process of methanol rectified column.

To investigate the influence of saturated fats, α-linolenic acid, EPA and DHA on the lipid hydroperoxide concentration and fatty acid composition in liver microsomes and in plasma lipid of rabbits, the animals were fed on the perilla oil rich α-linolenic acid or sardine oil rich EPA and DHA diet for four weeks Were examined. The fatty acid composition of plasma lipid and liver microsomes of rabbits fed on the perilla oil diet was an accumulation of arachidonic acid(AA) 20:4 n-6, eicosapentaenoic acid(EPA) 20:5 n-3, and docosahexaenoic acid(DHA) 22:6 n-3, The fatty acid composition of plasma lipid and liver microsomes of rabbits fed on the sardine oil was an accumulation of α-linolenic acid(LNA) 18:3 n-3, and arachidonic acid(AA) 20:4. The p/s ratio of rabbits fed on the perilla oil diet changed from 7.4 to 2.27 for plasma lipid and 2.47 for liver microsomes. The concentration of lipid hydroperoxide was 3.48 nmol MDA/ml and 4.35 nmol MDA/ml for plasma lipid and liver microsomes, respectively, in perilla oil diet. The lipid hydroperoxide liver was 4.22 nmol MDA/ml and 67 nmol MDA/ml for plasma lipid and liver microsornes in sardine oil diet.

In order to develope the method of quantitative determination of lipid hydroperoxide in human blood serum, we tried the ferrothiocyanate method to total lipids extracted by Bligh-Dyer method and obtained the results as follows. 1. The maximum absorbance showed at the concentration of Mohr's solution, 0.127M at pH 1.70 and ammonium thiocyanate solution, 3.95M in the ferrothiocyanate method. 2. When hydrogen peroxide, cumene hydroperoxide, and oxidized linoleic acid were added to serum, and extracted them by Bligh-Dyer method to examine the extraction efficiency, we confirmed that cumene hydroperoxide and oxidized linoleic acid were extracted in CHCI3 phase, and hydrogen peroxide in MeOH-H2O phase, respectively. 3. The concentration of lipid hydroperoxide of total lipids extracted from normal adult serum was 2.0×10-5M, and increased proportionally the concentration of lipid hydroperoxide by increasing the amount of serum. 4. When we compared the total lipids extracted by Bligh-Dyer method and total lipids extracted after lipoprotein is precipitated by Yagi method in human blood serum, the concentration of lipid hydroperoxide was showed nearly the same value. From our results, we concluded that the concentration of lipid hydroperoxide in human blood serum could be determined quantitatively by ferrothiocyanate method.

The purpose of current study is to investigate the beneficial effect of enzyme (Alcalase) hydrolysates of silk protein in rat. Alcalase-treated silk protein hydrolysate (ATSH) itself did not show any cytotoxicity on the hepatic tissues and blood biochemistry, similar to the normal condition. ATSH played a protective role in tert-butyl hydroperoxide (t-BHP)-induced hepatotoxicity and liver damage. The values of AST (aspartate aminotransferase) and ALT (alanine aminotransferase), which are the indicators of the liver function, were effectively alleviated with the ATSH treatment in a dose dependent manner. The level of Lactate dehydrogenase (LDH) and Malondialdehyde (MDA), which were increased with t-BHP treatment, were significantly reduced by ATSH. High dose of ATSH (2 g/kg) reduced the t-BHP-induced LDH release by 48%. Antioxidant and antioxidant enzymes in liver cells were significantly increased by ATSH treatment in their level and activities. ATSH (2 g/kg) increased glutathione (GSH), an intracelluar antioxidant, by 2.5-fold compared with the t-BHP treated group. The activities of glutathione-s-transferase (GST), superoxide dismutase (SOD), and catalase were also elevated by 38%, 60%, and 45%, respectively, with ATSH (2 g/kg) treatment. The antioxidative effect of ATSH was recapitulated to the protection from t-BHP induced liver damages in hematoxylin and eosin (H&E) staining. Thus, ATSH might be used as a hepatoprotective agent.