• Title/Summary/Keyword: Reactive species oxygen (ROS)

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Effect of Moutan Cortex Radicis on gene expression profile of differentiated PC12 rat cells oxidative-stressed with hydrogen peroxide (모단피의 PC12 cell 산화억제 효과 및 neuronal 유전자 발현 profile 분석에 대한 연구)

  • Kim Hyun Hee;Rho Sam Woong;Na Youn Gin;Bae Hyun Su;Shin Min Kyu;Kim Chung Suk;Hong Moo Chang
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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    • pp.529-541
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    • 2003
  • Yukmijihwang-tang has been widely used as an and-aging herbal medicine for hundred years in Asian countries. Numerous studies show that Yukmijihwangtang has anti-oxidative effect both in vivo and in vitro. It has been reported that Moutan Cortex Radicis extract (MCR) was the most effective herb in Yukmijihwang-tang on undifferentiated PC12 cells upon oxidative-stressed with hydrogen peroxide. The purpose of this study is to; 1) evaluate the recovery of neuronal damage by assessing the anti-oxidant effect of MCR on PC12 cells differentiated with nerve growth factor (NGF), 2) identify candidate genes responsible for anti-oxidative effect on differentiated PC12 cells by oligonucleotide chip microarray. PC12 cells, which were differentiated by treating with NGF, were treated without or with hydrogen peroxide in the presence or absence of various concentration of MCR. Cell survival was determined by using MTS assay. Measurement of intracellular reactive oxygen species (ROS) generation was determined using the H2DCFDA assay The viability of cells treated with MCR was significantly recovered from stressed PC12 cell. In addition, wide rage of concentrations of MCR shows dose-dependent inhibitory effect on ROS production in oxidative-stressed cells. Total RNAs of cells without treatment(Control group), only treated with H₂O₂ (stressed group) and treated with both H₂O₂ and of MCR (MCR group) were isolated, and cDNAs was synthesized using oligoT7(dT) primer. The fragmented cRNAs, synthesized from cDNAs, were applied to Affymetrix GeneChip Rat Neurobiology U34 Array. mRNA of Calcium/calmodulin-dependent protein kinase II delta subunit(CaMKII), neuron glucose transporter (GLUT3) and myelin/oligodendrocyte glycoprotein(MOG) were downregulated in Stressed group comparing to Control group. P2X2-5 receptor (P2X2R-5), P2X2-4 receptor (P2X2R-4), c-fos, 25 kDa synaptosomal attachment protein(SNAP-25a) and GLUT3 were downregulated, whereas A2 adenosine receptor (A2AR), cathechol-O-methyltransferase(COMT), glucose transporter 1 (GLUT1), EST223333, heme oxygenase (HO), VGF, UI-R-CO-ja-a-07-0-Ul.s1 and macrophage migration inhibitory factor (MIF) were upregulated in MCA group comparing to Control group. Expression of Putative potassium channel subunit protein (ACK4), P2X2A-5, P2X2A-4, Interferon-gamma inducing factor isoform alpha precursor (IL-18α), EST199031, P2XR, P2X2 purinoceptor isoform e (P2X2R-e), Precursor interleukin 18 (IL-18) were downregulated, whereas MOO, EST223333, GLUT-1, MIF, Neuronatin alpha, UI-R-C0-ja-a-07-0-Ul.s1, A2. adenosine receptor, COMT, neuron-specific enolase (NSE), HO, VGF, A rat novel protein which is expressed with nerve injury (E12625) were upregulated in MCR group comparing to Stressed group. The results suggest that decreased viability and AOS production of PC12 cell by H₂O₂ may be, at lease, mediated by impaired glucose transporter expression. It is implicated that the MCR treatment protect PC12 cell from oxidative stress via following mechanisms; improving glucose transport into the cell, enhancing expression of anti-oxidative genes and protecting from dopamine cytotoxicity by increment of COMT and MIF expression. The list of differentially expressed genes may implicate further insight on the action and mechanism behind the anti-oxidative effects of herbal extract Moutan Cortex Radicis.

Screening of Useful Plants with Anti-inflammatory and Antioxidant Activity (항염증 및 항산화 활성 보유 유용 식물 탐색)

  • Lee, Seung-Eun;Choi, Jehun;Lee, Jeong-Hoon;Noh, Hyung-Jun;Kim, Geum-Sook;Kim, Jinkyung;Chung, Hae-Young;Kim, Seung-Yu
    • Korean Journal of Plant Resources
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    • v.26 no.4
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    • pp.441-449
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    • 2013
  • This study was conducted to select some useful plants as functional material candidates. A total of 38 plants were preliminarily screened for the anti-inflammatory and antioxidant activities. The preliminarily selected 8 plants were further investigated to verify the in vitro inhibitory effect on inflammation and oxidative stress. Boehmeria platanifolia (root), Carpinus coreana (branch), and Eupatorium japonicum (leaf) inhibited the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-treated RAW 264.7 cells. Eupatorium japonicum (leaf) suppressed the expression of cyclooxygenase-2 (COX-2), whereas Boehmeria platanifolia (root) and Prunus yedoensis (branch) inhibited the transcription of nuclear factor-kappa B (NF-${\kappa}B$). Treatment with the extracts ($2.5{\sim}20{\mu}g/ml$) of Abutilon theophrasti (leaf, flower/seed) and Hemistepta lyrata (stem) did not show toxicity on RAW 264.7 cell proliferation, but treatment with $2.5{\mu}g/ml$ of Boehmeria platanifolia (root) exhibited cell toxicity. Carpinus coreana (branch) and Prunus yedoensis (branch) showed potent scavenging activities on peroxynitrite. Akebia quinata (flower), Carpinus coreana (branch), and Prunus yedoensis (branch) effectively inhibited reactive oxygen species (ROS). Abutilon theophrasti (leaf), Boehmeria platanifolia (root), Carpinus coreana (branch), and Eupatorium japonicum (leaf) exhibited strong inhibitory capacity with regard to nitric oxide (NO) production. The results suggested that Abutilon theophrasti (leaf) has in vitro anti-inflammatory and antioxidant activities, and that is a useful functional material candidate.

Effect of Iron Excess-induced Oxidative Stress on Platelet Aggregation (과잉 철로 유도된 산화적 스트레스가 혈소판 활성화에 미치는 작용)

  • Seo, Geun-Young;Park, Hyo-Jin;Jang, Sung-Geun;Park, Young-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.8
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    • pp.979-984
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    • 2006
  • Although iron is essential for many physiological processes, excess iron can lead to tissue damage by promoting the generation of reactive oxygen species (ROS). There is increasing evidence that ROS might play an important role in the pathogenesis of cardiovascular disease. However, the effects of iron excess on platelet function and the thrombotic response to vascular injury are not well understood. We examined the effects of iron excess-induced oxidative stress and the antioxidants on platelet aggregation. Oxidative stress was accessed by either free iron $(Fe^{+2})$ or hydrogen peroxide $(H_2O_2)$, as well as their combination on washed rabbit platelets (WPs) in vitro. When WPs were stimulated with either $Fe^{+2}$ alone or a subthreshold concentration of collagen, which gave an aggregatory curve with a little effect, and a dose dependent increase in platelet aggregation was observed by increasing concentrations of $Fe^{+2}$ with $H_2O_2$. This aggregation was associated with the iron-catalyzed formation of hydroxyl radicals from $H_2O_2$, and were inhibited by NAD/NADP (proton acceptor), catalase $(H_2O_2\;scavenger)$, tiron (iron chelator), mannitol (hydroxyl radical scavenger), and indomethacin (cyclooxygenase inhibitor), but not by NADH/NADPH (proton donor), superoxide mutase, and aspirin. However, NADH/NADPH, an essential cofactor for the antioxidant capacity by the supply of reducing potentials, showed the effect of an enhanced radical formation, suggesting a role for NADH/NADPH-dependent oxidase. These results suggest that iron $(Fe^{+2})$ can directly interact with washed rabbit platelets and this aggregation be mediated by OH formation as in the Fenton reaction, inhibited by radical scavengers.

Antioxidative Effect and Active Component Analysis of Quercus salicina Blume Extracts (참가시나무의 항산화 효과 및 활성 성분 분석)

  • Lee, Hye-Jin;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.37 no.2
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    • pp.143-152
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    • 2011
  • In this study, the antioxidative activity, inhibitory effects on tyrosinase and elastase, and active components of Quercus salicina Blume extracts were investigated. Q. salicina Blume was extracted using 50 % ethanol, from which ethyl acetate and aglycone fractions were prepared. The DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging activity ($FSC_{50}$) of Q. salicina Blume aglycone fraction was the highest ($8.25\;{\mu}g$/mL). The luminol-dependent chemiluminescence assay showed that reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of Q. salicina Blume aglycone fraction on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system was the most prominent at $0.039\;{\mu}g$/mL. The protective effects of extract/fractions of Q. salicina Blume against the rose-bengal sensitized photohemolysis of human erythrocytes were increased in a concentration dependent manner ($1{\sim} 25\;{\mu}g$/mL). Especially, ${\tau}_{50}$ of aglycone fraction in $10 \;{\mu}g$/mL concentration showed the most protective effect at 259.9 min. The inhibitory effects ($IC_{50}$) on tyrosinase and elastase of Q. salicina Blume extracts were higher at aglycone fraction (respectively, $21.82 \;{\mu}g$/mL, $41.18\;{\mu}g$/mL). Active component analysis by TLC and HPLC showed quercetin, keampferol, catechin, quercitrin, isoquercitrin, hyperoside, and etc. These results indicate that Q. salicina Blume extract has strong antioxidative activity and can be used as antioxidant. Particularly, aglycone fraction of Q. salicina Blume showed superior antioxdative activity and high inhibitory effect on tyrosinase and elastase. Therefore, aglycone fraction of Q. salicina Blume could be applicable to new functional cosmetics.

High Glucose Induces Apoptosis through Caspase-3 Dependent Pathway in Human Retinal Endothelial Cell Line (인간망막 내피세포주에서 고농도 포도당이 caspase-3 경로를 통해 세포자연사 유도)

  • Seo, Eun-Sun;Chae, Soo-Chul;Kho, Eun-Gyeong;Lee, Jong-Bin
    • Korean Journal of Environmental Biology
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    • v.27 no.1
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    • pp.66-72
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    • 2009
  • Diabetic Retinopathy (DR) is a leading cause of blindness among adults in the western countries. Hyperglycemia is a condition, that induces apoptotic cell death in a variety of cell types in diabetes, but the mechanism remains unclear. The aim of the study is to understand the effects of high Glucose on Human Retinal Endothelial Cells. Retinal endothelial cells were cultured in Iscove's Modified Dulbecco's Medium (IMDM) containing 5, 25 and 50 mM Glucose, incubated for 24, 36 and 48 hours in humidified 5 % CO$_2$ incubator at 37$^{\circ}C$. Human Retinal Endothelial Cell Line (HREC) were characterized for morphology with different treatment by phase contrast microscopic analysis. Number of dead and viable cells was counted by trypan blue exclusion and supported by MTT assay. The intracellular Hydrogen peroxide (H$_2$O$_2$), a Reactive Oxygen Species (ROS) generation in high glucose conditions was assessed by FOX II assay and apoptosis by caspase-3 assay. The high glucose treated cells undergoing DNA fragmentation was witnessed by Agarose gel electrophoresis. We found that the cells incubated with 25 and 50 mM glucose containing medium for 48 hours altered the morphology of the cell, induced apoptosis and DNA fragmentation. The dead cell number were high in 25 and 50 mM when compared to the cells incubated with 5 mM glucose for 24, 36, and 48 hours. Also, the H$_2$O$_2$ levels and the activity of caspase-3 were increased in high glucose treated cells. Conclusions/interpretation: Our results demonstrated that elevated glucose induces apoptosis in cultured HREC. The hyperglycemia-induced increase in apoptosis may be dependent on caspase activation. The association between ROS generation and caspase-3 activation on high glucose treated cells is yet to be investigated.

Preventive Effects of Rosa rugosa Root Extract on Advanced Glycation End product-Induced Endothelial Dysfunction (해당근 추출물의 항산화 활성 및 최종당화산물에 의한 혈관내피세포 기능장애 억제활성)

  • Nam, Mi-Hyun;Lee, Hyun-Sun;Hong, Chung-Oui;Koo, Yoon-Chang;Seo, Mun-Young;Lee, Kwang-Won
    • Korean Journal of Food Science and Technology
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    • v.42 no.2
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    • pp.210-216
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    • 2010
  • Rosa rugosa has traditionally been used as a folk remedy for diabetes. The objective of this study was therefore to demonstrate the inhibition of endothelial dysfunction activities through antioxidants and the anti-glycation of Rosa rugosa roots. Dried roots of Rosa rugosa were boiled in methanol for three hours, evaporated and lyophilized with a freeze-dryer. The methanolic extract of Rosa rugosa roots (RRE) was tested for antioxidant activities by measuring total polyphenol (TP) content, flavonoid content, 1,1-diphenyl-2-picrylhydrazyl free radical-scavenging activity (DPPH) assay, and ferric-reducing antioxidant power (FRAP) assay. The total TP content, flavonoid content, FRAP value, and $DPPHSC_{50}$ are $345.2\;{\mu}g$ gallic acid equivalents/mg dry matter (DM), $128.1\;{\mu}g$ quercetin equivalents/mg DM, 2.2 mM $FeSO_4$/mg DM and $34.2\;{\mu}g$ DM/mL, respectively. Treatment of RRE significantly lowered fluorescent formation due to advanced glycation reaction. In addition, reactive oxygen species (ROS) scavenging assay, monocyte adherent assay and transendothelial electrical resistance (TEER) assay were performed to investigate the possibility that RRE improves endothelial dysfunction-induced diabetic complications. The adhesion of THP-1 to treated HUVEC with RRE ($100\;{\mu}g/mL$; 33% and $500\;{\mu}g/mL$; 75%) was significantly reduced compared to HUVEC stimulated by glyceraldehydes-AGEs (advanced glycation end product). The TEER value ($88\;{\Omega}{\cdot}cm^2$) of stimulated HUVEC by glyceraldehydes-AGEs was reduced compared to non-stimulation ($113\;{\Omega}{\cdot}cm^2$). However, normalization with RRE increased endothelial permeability in a dose-dependent manner ($100\;{\mu}g/mL$; $102\;{\Omega}{\cdot}cm^2$ and $500\;{\mu}g/mL$; $106\;{\Omega}{\cdot}cm^2$). Thus, these results suggest that Rosa rugosa roots could be a novel candidate for the prevention of diabetic complications through antioxidants and inhibition of advanced glycation end product formation.

Protective effect of Eucommia ulmoides oliver leaves against PM2.5-induced oxidative stress in neuronal cells in vitro (미세먼지(PM2.5)로 유도된 산화적 스트레스에 대한 두충(Eucommia ulmoides Oliver) 잎의 in vitro 뇌 신경세포 보호 효과)

  • Kim, Min Ji;Kang, Jin Yong;Park, Seon Kyeong;Kim, Jong Min;Moon, Jong Hyun;Kim, Gil Han;Lee, Hyo Lim;Jeong, Hye Rin;Heo, Ho Jin
    • Korean Journal of Food Science and Technology
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    • v.53 no.4
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    • pp.423-433
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    • 2021
  • This study was performed to examine the neuroprotective effect of the ethyl acetate fraction from Eucommia ulmoides oliver leaf (EFEL) on PM2.5-induced cytotoxicity. EFEL had higher total phenolic and flavonoid contents than the other fractions. In ABTS and DPPH radical scavenging activities, the IC50 of EFEL was measured as 212.80 and 359.13 ㎍/mL, respectively. To investigate the neuroprotective effect of EFEL, MTT and DCF-DA assays were performed on HT22, MC-IXC, and BV-2 cells. EFEL effectively decreased PM2.5-induced intercellular reactive oxygen species (ROS) content and inhibited PM2.5-induced cell death. In the results of protein expression related to cellular cytotoxicity on microglial cells (BV-2), EFEL had an improvement effect on cell apoptosis and inflammatory pathways. Rutin and chlorogenic acid were identified as the main physiological compounds. Moreover, it was expected that EFEL, including rutin and chlorogenic acid, could be functional food substances with neuroprotective effects against PM2.5-induced oxidative stress.

Antioxidant and Anti-inflammatory Activities of Water and the Fermentation Liquid of Sea Tangle (Saccharina japonica) (다시마 물 추출액과 발효액의 항산화 및 항염증 활성)

  • Jung, Kyung Im;Kim, Bo Kyung;Kang, Jeong Hyeon;Oh, Geun Hye;Kim, In Kyung;Kim, Mihyang
    • Journal of Life Science
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    • v.29 no.5
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    • pp.596-606
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    • 2019
  • The study investigated the physiochemical properties and the antioxidant and anti-inflammatory activities of the sea tangle (Saccharina japonica) in a water extract before (STWE) and after (STFL) fermentation with Lactobacillus brevis. The pH values of STWE and STFL were 6.18 and 4.16, and the sugar contents were $8.50^{\circ}Brix$ and $7.40^{\circ}Brix$, respectively. The main free amino acids of STWE and STFL were glutamic acid, aspartic acid, and alanine, and the ${\gamma}$-amino butyric acid (GABA) content was increased by fermentation. The total polyphenol contents of STWE and STFL were 498.29 and 615.77 mg gallic acid equivalent (GAE)/ml, respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities of STWE and STFL were markedly increased in a dose-dependent manner, and revealed about 89.89% and 96.94% activities, respectively, at 10% concentration (p<0.05). The superoxide dismutase (SOD) activities of STWE and STFL were also markedly increased in a dose-dependent manner, and the activity of STFL was significantly increased when compared with STWE (p<0.05). The anti-inflammatory activity was examined in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. STWE and STFL decreased the production of reactive oxygen species (ROS), which had levels of about 189.90% and 174.69% at 1% concentration, respectively (p<0.05). The contents of pro-inflammatory cytokines, such as tumor necrosis factor-alpha ($TNF-{\alpha}$) and interleukin-6 (IL-6), were decreased more by addition of STFL than by addition of STWE. The STWE and STFL showed high antioxidant and anti-inflammatory activity, and these activities were increased by fermentation. Therefore, sea tangle extracts can be used as functional food materials.

Gene Expression of Detoxification Enzymes in Tenebrio molitor after Fungicide Captan Exposure (살진균제인 캡탄 처리 후 갈색거저리의 해독효소 유전자 발현)

  • Jang, Ho am;Baek, Hyoung-Seon;Kim, Bo Bae;Kojour, Maryam Ali Mohammadie;Patnaik, Bharat Bhusan;Jo, Yong Hun;Han, Yeon Soo
    • Korean journal of applied entomology
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    • v.61 no.1
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    • pp.155-163
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    • 2022
  • The application of fungicides is indispensable to global food security, and their use has increased in recent times. Fungicides, directly or indirectly, have impacted insects, leading to genetic and molecular-level changes. Various detoxification mechanisms allow insects to eliminate reactive oxygen species (ROS) toxicity induced by agrochemicals including fungicides. In the present study, we analyzed the mRNA expression levels of detoxifying enzymes in Tenebrio molitor larvae following exposure to non-lethal doses (0.2, 2, and 20 ㎍/µL) of a fungicide captan. Transcripts of peroxidases (POXs), catalases (CATs), superoxide dismutases (SODs), and glutathione-s-transferases (GSTs) were screened from the T. molitor transcriptome database. RT-qPCR analysis showed that TmPOX5 mRNA increased significantly 24 h post-captan exposure. A similar increase was noticed for TmSOD4 mRNA 3 h post-captan exposure. Moreover, the expression of TmCAT2 mRNA increased significantly 24 h post-treatment with 2 ㎍/µL captan. TmGST1 and TmGST3 mRNA expression also increased noticeably after captan exposure. Taken together, these results suggest that TmPOX5 and TmSOD4 mRNA can be used as biomarkers or xenobiotics sensors for captan exposure in T. molitor, while other detoxifying enzymes showed differential expression.

Induction of Phase I, II and III Drug Metabolism/Transport by Xenobiotics

  • Xu Chang Jiang;Li Christina YongTao;Kong AhNg Tony
    • Archives of Pharmacal Research
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    • v.28 no.3
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    • pp.249-268
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    • 2005
  • Drug metabolizing enzymes (DMEs) play central roles in the metabolism, elimination and detoxification of xenobiotics and drugs introduced into the human body. Most of the tissues and organs in our body are well equipped with diverse and various DMEs including phase I, phase II metabolizing enzymes and phase III transporters, which are present in abundance either at the basal unstimulated level, and/or are inducible at elevated level after exposure to xenobiotics. Recently, many important advances have been made in the mechanisms that regulate the expression of these drug metabolism genes. Various nuclear receptors including the aryl hydrocarbon receptor (AhR), orphan nuclear receptors, and nuclear factor-erythoroid 2 p45-related factor 2 (Nrf2) have been shown to be the key mediators of drug-induced changes in phase I, phase II metabolizing enzymes as well as phase III transporters involved in efflux mechanisms. For instance, the expression of CYP1 genes can be induced by AhR, which dimerizes with the AhR nuclear translocator (Arnt) , in response to many polycyclic aromatic hydrocarbon (PAHs). Similarly, the steroid family of orphan nuclear receptors, the constitutive androstane receptor (CAR) and pregnane X receptor (PXR), both heterodimerize with the ret-inoid X receptor (RXR), are shown to transcriptionally activate the promoters of CYP2B and CYP3A gene expression by xenobiotics such as phenobarbital-like compounds (CAR) and dexamethasone and rifampin-type of agents (PXR). The peroxisome proliferator activated receptor (PPAR), which is one of the first characterized members of the nuclear hormone receptor, also dimerizes with RXR and has been shown to be activated by lipid lowering agent fib rate-type of compounds leading to transcriptional activation of the promoters on CYP4A gene. CYP7A was recognized as the first target gene of the liver X receptor (LXR), in which the elimination of cholesterol depends on CYP7A. Farnesoid X receptor (FXR) was identified as a bile acid receptor, and its activation results in the inhibition of hepatic acid biosynthesis and increased transport of bile acids from intestinal lumen to the liver, and CYP7A is one of its target genes. The transcriptional activation by these receptors upon binding to the promoters located at the 5-flanking region of these GYP genes generally leads to the induction of their mRNA gene expression. The physiological and the pharmacological implications of common partner of RXR for CAR, PXR, PPAR, LXR and FXR receptors largely remain unknown and are under intense investigations. For the phase II DMEs, phase II gene inducers such as the phenolic compounds butylated hydroxyanisol (BHA), tert-butylhydroquinone (tBHQ), green tea polyphenol (GTP), (-)-epigallocatechin-3-gallate (EGCG) and the isothiocyanates (PEITC, sul­foraphane) generally appear to be electrophiles. They generally possess electrophilic-medi­ated stress response, resulting in the activation of bZIP transcription factors Nrf2 which dimerizes with Mafs and binds to the antioxidant/electrophile response element (ARE/EpRE) promoter, which is located in many phase II DMEs as well as many cellular defensive enzymes such as heme oxygenase-1 (HO-1), with the subsequent induction of the expression of these genes. Phase III transporters, for example, P-glycoprotein (P-gp), multidrug resistance-associated proteins (MRPs), and organic anion transporting polypeptide 2 (OATP2) are expressed in many tissues such as the liver, intestine, kidney, and brain, and play crucial roles in drug absorption, distribution, and excretion. The orphan nuclear receptors PXR and GAR have been shown to be involved in the regulation of these transporters. Along with phase I and phase II enzyme induction, pretreatment with several kinds of inducers has been shown to alter the expression of phase III transporters, and alter the excretion of xenobiotics, which implies that phase III transporters may also be similarly regulated in a coordinated fashion, and provides an important mean to protect the body from xenobiotics insults. It appears that in general, exposure to phase I, phase II and phase III gene inducers may trigger cellular 'stress' response leading to the increase in their gene expression, which ultimately enhance the elimination and clearance of these xenobiotics and/or other 'cellular stresses' including harmful reactive intermediates such as reactive oxygen species (ROS), so that the body will remove the 'stress' expeditiously. Consequently, this homeostatic response of the body plays a central role in the protection of the body against 'environmental' insults such as those elicited by exposure to xenobiotics.