Livers Of Sprague-Dawley Rats Research Articles

In vivo validation and physiologically based biokinetic modeling of the inhibition of SULT-mediated estragole DNA adduct formation in the liver of male Sprague-Dawley rats by the basil flavonoid nevadensin

The present work investigates whether the previous observation that the basil flavonoid nevadensin is able to inhibit sulfotransferase (SULT)-mediated estragole DNA adduct formation in primary rat hepatocytes could be validated in vivo. Estragole and nevadensin were co-administered orally to Sprague-Dawley rats, at a ratio reflecting their presence in basil. Moreover, previously developed physiologically based biokinetic (PBBK) models to study this inhibition in rat and in human liver were refined by including a submodel describing nevadensin kinetics. Nevadensin resulted in a significant 36% reduction in the levels of estragole DNA adducts formed in the liver of rats. The refined PBBK model predicts the formation of estragole DNA adducts in the liver of rat with less than twofold difference compared to in vivo data and suggests more potent inhibition in the liver of human compared to rat due to less efficient metabolism of nevadensin in human liver and intestine. Given the role of the SULT-mediated DNA adduct formation in the hepatocarcinogenicity of estragole, the results of the present study suggest that the likelihood of bioactivation and subsequent adverse effects in rodent bioassays may be lower when estragole is dosed with nevadensin compared to dosing of pure estragole.

Oxidative stress increased hepatotoxicity induced by nano‐titanium dioxide in BRL‐3A cells and Sprague–Dawley rats

Extensive studies have shown that titanium dioxide (TiO2 ) nanomaterials (NMs) can cause toxicity in vitro and in vivo under normal conditions. However, an adverse effect induced by nano-TiO2 in many diseased conditions, typically characterized by oxidative stress (OS), remains unknown. We investigated the toxicity of nano-TiO2 in rat liver cells (BRL-3A) and Sprague-Dawley (SD) rat livers under OS conditions, which were generated using hydrogen peroxide (H2 O2 ) in vitro and alloxan in vivo, respectively. In vitro results showed that cell death ratios after nano-TiO2 exposure were significantly enhanced (up to 2.62-fold) in BRL-3A cells under OS conditions, compared with normal controls. Significant interactions between OS conditions and nano-TiO2 resulted in the rapid G0/G1 to S phase transition and G2/M arrest, which were opposite to G0/G1 phase arrest in cells after NMs exposure only. In vivo results showed that obvious pathological changes in rat livers and the increased activities of four enzymes (i.e. aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and alkaline phosphatase) owing to liver damage after nano-TiO2 exposure under OS conditions, compared with their healthy controls. In addition, compared with increased hepatotoxicity after nano-TiO2 exposure, micro-TiO2 showed no adverse effects to cells and rat livers under OS conditions. Our results suggested that OS conditions synergistically increase nano-TiO2 induced toxicity in vitro and in vivo, indicating that the evaluation of nanotoxicity under OS conditions is essentially needed prior to various applications of NMs in foods, cosmetics and potential treatment of diseases.

Non-Specific Protein Modifications by a Phytochemical Induce Heat Shock Response for Self-Defense

Accumulated evidence shows that some phytochemicals provide beneficial effects for human health. Recently, a number of mechanistic studies have revealed that direct interactions between phytochemicals and functional proteins play significant roles in exhibiting their bioactivities. However, their binding selectivities to biological molecules are considered to be lower due to their small and simple structures. In this study, we found that zerumbone, a bioactive sesquiterpene, binds to numerous proteins with little selectivity. Similar to heat-denatured proteins, zerumbone-modified proteins were recognized by heat shock protein 90, a constitutive molecular chaperone, leading to heat shock factor 1-dependent heat shock protein induction in hepa1c1c7 mouse hepatoma cells. Furthermore, oral administration of this phytochemical up-regulated heat shock protein expressions in the livers of Sprague-Dawley rats. Interestingly, pretreatment with zerumbone conferred a thermoresistant phenotype to hepa1c1c7 cells as well as to the nematode Caenorhabditis elegans. It is also important to note that several phytochemicals with higher hydrophobicity or electrophilicity, including phenethyl isothiocyanate and curcumin, markedly induced heat shock proteins, whereas most of the tested nutrients did not. These results suggest that non-specific protein modifications by xenobiotic phytochemicals cause mild proteostress, thereby inducing heat shock response and leading to potentiation of protein quality control systems. We considered these bioactivities to be xenohormesis, an adaptation mechanism against xenobiotic chemical stresses. Heat shock response by phytochemicals may be a fundamental mechanism underlying their various bioactivities.

Minor Groove Binder Distamycin Remodels Chromatin but Inhibits Transcription

The condensed structure of chromatin limits access of cellular machinery towards template DNA. This in turn represses essential processes like transcription, replication, repair and recombination. The repression is alleviated by a variety of energy dependent processes, collectively known as “chromatin remodeling”. In a eukaryotic cell, a fine balance between condensed and de-condensed states of chromatin helps to maintain an optimum level of gene expression. DNA binding small molecules have the potential to perturb such equilibrium. We present herein the study of an oligopeptide antibiotic distamycin, which binds to the minor groove of B-DNA. Chromatin mobility assays and circular dichroism spectroscopy have been employed to study the effect of distamycin on chromatosomes, isolated from the liver of Sprague-Dawley rats. Our results show that distamycin is capable of remodeling both chromatosomes and reconstituted nucleosomes, and the remodeling takes place in an ATP-independent manner. Binding of distamycin to the linker and nucleosomal DNA culminates in eviction of the linker histone and the formation of a population of off-centered nucleosomes. This hints at a possible corkscrew type motion of the DNA with respect to the histone octamer. Our results indicate that distamycin in spite of remodeling chromatin, inhibits transcription from both DNA and chromatin templates. Therefore, the DNA that is made accessible due to remodeling is either structurally incompetent for transcription, or bound distamycin poses a roadblock for the transcription machinery to advance.

Mitragyna speciosa Korth leaves extracts induced the CYP450 catalyzed aminopyrine-N-demethylase (APND) and UDP-glucuronosyl transferase (UGT) activities in male Sprague-Dawley rat livers

Mitragyna speciosa leaves have been abused by drug addicts as some of the alkaloids (mainly mitragynine) from the plant possess opiate and cocaine-like effects. These bring to its prohibition in Malaysia in 2004 as consumption of M. speciosa leaves has been perceived to lead to the abuse of other drugs such as cannabis and heroin. In the current study, the in vitro and in vivo effects of M. speciosa methanolic, aqueous and total alkaloid leaves extracts on drug metabolizing enzymes, namely, cytochrome P450s (CYP450s) and UDP-glucuronosyl transferase (UGT) had been evaluated in rat liver cytosolic fraction and microsomes. Aminopyrine and p-nitrophenol (pNP) were employed as probe substrates in aminopyrine N-demethylase (APND) and UGT enzyme assays, respectively. Furthermore, mitragynine was also tested in vitro for its likelihood to inhibit APND and UGT activity. The assessment of the enzyme activity was conducted using spectrophotometric methods. In vitro, the IC50 value could only be obtained for the methanolic extract in APND study (595.30±30.78 µg/mL) and not in other studies due to the enzyme percentage inhibitions being <70%. In contrast to the in vitro study, the oral treatment of male Sprague-Dawley rats for 14 days with 50, 100 and 200 mg/kg of methanolic and aqueous extracts and with 5, 10 and 20 mg/kg of total alkaloid extract showed a profound increment on the APND and UGT activities. The current findings showed that possibilities exist for herb-drug interaction with increased clearance of drugs, which are primarily metabolized by CYP450s and UGT1A6 among M. speciosa leaves extract users.

Magnesium Deficiency Induces the Emergence of Mast Cells in the Liver of Rats

Mast cells, multifunctional effector cells of the immune system, are implicated in the pathogenesis of hepatic steatosis and fibrosis. Magnesium (Mg) deficiency was reported to increase triglyceride concentration in the liver, and to exacerbate the collagen deposition induced by carbon tetrachloride in the liver. Although Mg deficiency increases mast cells in the small intestine, the kidney and bone marrow, the effect of Mg deficiency on mast cells has not been clarified in the liver. We examined the emergence of mast cells in the liver of Sprague-Dawley rats given an Mg-deficient diet. Rats were fed a control diet or an Mg-deficient diet for 4 wk. Mg deficiency increased the levels of mRNA known to be expressed by mast cells in the liver; the mRNA of α- and β-chain high-affinity immunoglobulin E receptor (FcεR1α, FcεR1β), and the mRNA of mast cell protease 1 (Mcpt1), and mast cell protease 2 (Mcpt2). Histological observation showed that some mast cells were locally distributed around portal triads in the Mg-deficient group but mast cells were scarcely found in the control group. These results clearly indicate that Mg deficiency induces the emergence of mast cells around portal triads of the liver in Sprague-Dawley rats.

Effect of sprout extract from Tuscan black cabbage on xenobiotic-metabolizing and antioxidant enzymes in rat liver

In recent years, health protection by natural products has received considerable attention, and a multitude of nutraceuticals have been characterized and their use promoted. Dietary consumption of Cruciferous vegetables, rich in glucosinolates (GLs), and their myrosinase-mediated hydrolysis products isothiocyanates (ITCs), were associated with reductions in cancer risk. In this study, the chemo-preventive potential of sprout extract of Tuscan black cabbage (Brassica oleracea L. var. acephala subvar. Laciniata L.) (TBCSE), through modulation of the xenobiotic-metabolizing apparatus and antioxidant defenses, was investigated in Sprague-Dawley rat liver. TBCSE was administered either orally or intraperitoneally, at a dose of 15mg/kg b.w., daily for twenty-one consecutive days, in the absence or presence of exogenous myrosinase, β-thioglucoside glucohydrolase (MYR), to distinguish the effects of intact GLs and ITCs, in the context of the extract. A complex, mild modulation pattern of P450-related monooxygenases was observed, mainly regarding CYP content (up to 36% loss), NADPH cytochrome (P450) c-reductase (up to 26% loss), CYP1A1 (up to 23% loss), but no evident distinctions among the effects of the extracts containing GLs or ITCs, were noted. In contrast, significant inductions of phase-II enzymes (up to 107% for UDP-glucuronosyl-transferase, and up to 36% for glutathione S-transferase) were recorded only where the GLs to ITCs conversion had occurred. A boosting effect on catalase (up to 38%), NAD(P)H:quinone reductase (up to 70%), glutathione reductase and glutathione peroxidase (up to 10%) was also recorded, suggesting an indirect antioxidant capacity of the extracts. Overall, the general phase-I inhibition, together with the up-regulation of detoxifying phase-II and antioxidant enzymes, exerted by the TBCSE supplementation, seem to be in line with the classical chemopreventive theory, but whether the addition of exogenous MYR is relevant, still remains to be clarified. These results are in support of the potential health-promoting application of TBCSE, as a nutraceutical.

Ochratoxin A causes oxidative stress and cell death in rat liver

The effect of ochratoxin A (OTA) on oxidant/antioxidant status and on histopathological changes and apoptotic cell death in livers of male Sprague-Dawley rats has been investigated. OTA (0.5 mg/kg body weight/day) was administered by oral route for 14 days. Plasma biochemical parameters, activities of liver selenoenzymes (glutathione peroxidase-1, thioredoxin reductase) and antioxidant enzymes (catalase, superoxide dismutase, glutathione S-transferase), and levels of total glutathione and thiobarbituric acid reactive substance in hepatic tissue were measured. In addition, histopathological examinations were performed and apoptotic cell death of hepatocytes was evaluated by the TdT-mediated dUTP nick-end labelling (TUNEL) assay. OTA exposure was found to induce focal necrosis of hepatocytes and mononuclear cell infiltration. Besides, exposure to OTA caused an imbalance in oxidant and antioxidant parameters in the rat liver, as evidenced by significant decreases in glutathione S-transferase activity and glutathione levels, and marked increases in concentrations of thiobarbituric acid reactive substances. Furthermore, TUNEL analysis revealed a significant ~2.7-fold increase in the number of TUNEL-positive liver cells of rats exposed to OTA compared to the control group. The results of this study showed that oxidative stress is at least one of the mechanisms underlying the hepatic toxicity of OTA, and that both necrosis and apoptosis are types of cell death in the hepatic toxicity of this mycotoxin.

Effect of taurine on IRAK4 and NF-kappa B in Kupffer cells from rat liver grafts after ischemia-reperfusion injury

BackgroundThe aim of this study was to explore the protective mechanisms of taurine pretreatment against hepatic ischemia/reperfusion injury after liver transplantation. MethodsA Sprague-Dawley–to–Sprague-Dawley rat liver transplantation model was used in this study. At 0, 60, and 180 minutes after reperfusion, expression of interleukin-1 receptor–associated kinase-4 (IRAK-4) messenger ribonucleic acid and protein in Kupffer cells was determined by real-time polymerase chain reaction and Western blotting. The activity of nuclear factor κB in Kupffer cells was determined by electrophoretic mobility shift assay. The serum tumor necrosis factor–α level was detected by enzyme-linked immunosorbent assay. Serum transaminases, liver histology, and animal survival were also investigated. ResultsAt 60 and 180 minutes after reperfusion, levels of IRAK-4 messenger ribonucleic acid and protein, activities of nuclear factor κB, and levels of serum transaminases and tumor necrosis factor–α were all obviously elevated. However, changes in these parameters in rats treated with taurine were remarkably attenuated at the indicated time points. ConclusionsThese data suggest that taurine could protect against hepatic ischemia/reperfusion injury after liver transplantation, and the protective effects may be through downregulation of IRAK-4 and downstream nuclear factor κB and tumor necrosis factor–α expression in Kupffer cells.

Radiofrequency Ablation: Effect of Tumor- and Organ-specific Pharmacologic Modulation of Arterial and Portal Venous Blood Flow on Coagulation Diameter in an N1-S1 Tumor Model

PurposeTo investigate inherent differences in vasculature of tumors versus normal parenchyma and efficacy of radiofrequency (RF) ablation with glucagon, adenosine, and a combination of the two compared with normal saline solution (NS) controls in an N1-S1 tumor model implanted in Sprague–Dawley rat livers. Materials and MethodsA total of 17 tumors were established in the left lobes of rats. Tumor perfusion relative to surrounding liver parenchyma was evaluated with contrast-enhanced ultrasound with intermittent-bolus technique before and after administration of glucagon, adenosine, a combination of the two, or NS. Tumors were ablated with a 22-gauge RF probe with 1 cm of exposed tip at 80 °C for 2 min. Tumor size, zone of necrosis, and viable tumor were measured in tumors after 2,3,5-triphenyltetrazolium chloride staining. Results were compared with degree of tumor perfusion. ResultsThe normalized tumor perfusion ratio did not significantly change with administration of NS (1.38% ± 3.93). Vasomodulation resulted in significant decreases in normalized tumor perfusion ratio: 66.22% ± 24.57 (P < .01) with glucagon, 71.45% ± 22.72 (P < .01) with adenosine, and 74.98% ± 16.58 (P < .01) with glucagon plus adenosine. After tumor ablation, there was an increase in size of the ablated area by 100%–165% in the three treatment groups compared with NS controls. Differences among treatment groups were not statistically significant. ConclusionsTumor blood flow may be significantly altered by using systemic injection of appropriate medications. This tumor- and organ-specific approach to tumor vasomodulation may be used to enhance current therapeutic options.

Central Glucocorticoid Administration Promotes Weight Gain and Increased 11β-Hydroxysteroid Dehydrogenase Type 1 Expression in White Adipose Tissue

Glucocorticoids (GCs) are involved in multiple metabolic processes, including the regulation of insulin sensitivity and adipogenesis. Their action partly depends on their intracellular activation by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1). We previously demonstrated that central GC administration promotes hyperphagia, body weight gain, hyperinsulinemia and marked insulin resistance at the level of skeletal muscles. Similar dysfunctions have been reported to occur upon specific overexpression of 11β-HSD1 in adipose tissue. The aim of the present study was therefore to determine whether the effects of central GC infusion may enhance local GC activation in white adipose tissue. Male Wistar and Sprague Dawley (SD) rats were intracerebroventricularly infused with GCs for 2 to 3 days. Body weight, food intake and metabolic parameters were measured, and expression of enzymes regulating 11β-HSD1, as well as that of genes regulated by GCs, were quantified. Central GC administration induced a significant increase in body weight gain and in 11β-HSD1 and resistin expression in adipose tissue. A decrease 11β-HSD1 expression was noticed in the liver of SD rats, as a partial compensatory mechanism. Such effects of GCs are centrally elicited. This model of icv dexamethasone infusion thus appears to be a valuable acute model, that helps delineating the initial metabolic defects occurring in obesity. An impaired downregulation of intracellular GC activation in adipose tissue may be important for the development of insulin resistance.

Determination of Tissue to Blood Partition Coefficients for Nonvolatile Herbicides, Insecticides, and Fungicides Using Negligible Depletion Solid-Phase Microextraction (nd-SPME) and Ultrafiltration

Partition coefficients (PCs) are used in physiologically based pharmacokinetic (PBPK) models to estimate the free concentration of a chemical in specific blood or organs. Biological PCtissue:blood (tissue to blood) values were determined for a series of nonvolatile herbicides, insecticides, and fungicides in liver, brain, skin, fat, kidneys, and muscle of male Sprague-Dawley rats using two different analytical methods. The free phase concentration (in phosphate-buffered saline) of a given chemical was measured in the presence and absence of tissue (including blood) and used to calculate the PC, defined as the ratio of the concentration of the chemical in saline to the concentration in the tissue. PCs were determined for 13 compounds with aqueous solubility ranging from 20 to 4100 mg/L, molecular weights from 187.3 to 342.2 g/mol, and log K ow values from –0.18 to 3.9. An ultrafiltration high-performance liquid chromatography (HPLC) method was implemented for compounds with log K ow near 0.1 or less and a negligible depletion solid-phase microextraction (nd-SPME) method for compounds with higher log K ow. PCtissue:saline coefficients of variation were 0.13 (n = 3 compounds) on average for the HPLC method and 0.29 (n = 10 compounds) for the nd-SPME method. Presented here is one of the most comprehensive data sets of biological partition coefficients for herbicides, insecticides, and fungicides.

Abstract No. 13: Radiofrequency ablation: effect of tumor and organ-specific pharmacologic modulation of arterial and portal venous blood flow on coagulation diameter in a N1-S1 tumor model

To investigate the inherent differences in the vasculature of tumors versus normal parenchyma and the efficacy of RF ablation using glucagon (GN), adneosine (AD), and a combination of AD + GN as compared with normal saline (NS) controls using an N1-S1 tumor model implanted in Sprague-Dawley rat livers. Specifically, we evaluated pharmacologic agents and doses that yielded the greatest amount of decreased tumor perfusion and resulted in a greater percentage of tumor coagulative necrosis.

Histopathological Effects of 2,4-Dichlorophenoxyacetic Acid on Sprague-Dawley Rats with Special Reference to its Possible Carcinogenicity

This study investigated the toxic effects of 2,4-dichlorophenoxyacetic acid on male Sprague-Dawley rats. In which, 30 rats were divided into three even groups. First group received orally normal saline (3 ml/kg b.w.) and kept as normal control in parallel to treated groups (5 rats each), second group received orally 2,4-dichlorophenoxyacetic acid (30 mg/kg b.w.) for 2 months and third group received orally 2,4-dichlorophenoxyacetic acid (30 mg/kg b.w.) for 6 months. At the end of each treatment, specimens from the liver, kidneys, lungs, testicles, epididymis and brain were obtained and subjected for histopathological examination. After 2 months of treatment with 2,4-dichlorophenoxyacetic acid, the overall changes were milder and ranged from vascular to necrobiotic findings. On the other hand, changes seen after 6 months were severe particularly in the liver and kidney. In the liver, there were focal areas of necrosis and preneoplastic changes in the form eosinophilic preneoplastic foci, oval cell proliferation and spongiotic pericytoma. Kidneys showed glomerular swelling, thickening of the glomerular basement membrane and proliferation of the renal tubular epithelium. Lesions in the other organs included necrosis and sloughing of bronchiolar epithelial lining and mononuclear cellular infiltration in the lungs, necrosis of seminiferous tubular epithelium in the testicles and neuronal degeneration in the brain. In conclusion, 2,4-dichlorophenoxyacetic acid induced deleterious pathological effects on the vital organs including preneoplastic changes in the liver in Sprague-Dawley rats.

Lentiviral vector-mediated down-regulation of IL-17A receptor in hepatic stellate cells results in decreased secretion of IL-6

To investigate the mechanism of interleukin (IL)-6 secretion through blocking the IL-17A/IL-17A receptor (IL-17RA) signaling pathway with a short hairpin RNA (shRNA) in hepatic stellate cells (HSCs) in vitro. HSCs were derived from the livers of adult male Sprague-Dawley rats. IL-6 expression was evaluated using real-time quantitative polymerase chain reaction and enzyme linked immunosorbent assay. The phosphorylation activity of p38 mitogen activated protein kinases (MAPK) and extracellular regulated protein kinases (ERK) 1/2 upon induction by IL-17A and suppression by IL-17RA shRNA were examined using Western blotting. IL-6 expression induced by IL-17A was significantly increased compared to control in HSCs (P < 0.01 in a dose-dependent manner). Suppression of IL-17RA using lentiviral-mediated shRNA inhibited IL-6 expression induced by IL-17A compared to group with only IL-17A treatment (1.44 ± 0.17 vs 4.07 ± 0.43, P < 0.01). IL-17A induced rapid phosphorylation of p38 MAPK and ERK1/2 after 5 min exposure, and showed the strongest levels of phosphorylation of p38 MAPK and ERK1/2 at 15 min in IL-17A-treated HSCs. IL-6 mRNA expression induced by IL-17A (100 ng/mL) for 3 h exposure was inhibited by preincubation with specific inhibitors of p38 MAPK (SB-203580) and ERK1/2 (PD-98059) compared to groups without inhibitors preincubation (1.67 ± 0.24, 2.01 ± 0.10 vs 4.08 ± 0.59, P < 0.01). Moreover, Lentiviral-mediated IL-17RA shRNA 1 inhibited IL-17A-induced IL-6 mRNA expression compared to random shRNA in HSCs (1.44 ± 0.17 vs 3.98 ± 0.68, P < 0.01). Lentiviral-mediated IL-17RA shRNA 1 inhibited phosphorylation of p38 MAPK and ERK1/2 induced by 15 min IL-17A (100 ng/mL) exposure. Down-regulation of the IL-17RA receptor by shRNA decreased IL-6 expression induced by IL-17A via p38 MAPK and ERK1/2 phosphorylation in HSCs. Suppression of IL-17RA expression may be a strategy to reduce the inflammatory response induced by IL-17A in the liver.

Measuring In Vitro Biotransformation Rates of Super Hydrophobic Chemicals in Rat Liver S9 Fractions Using Thin-Film Sorbent-Phase Dosing

Methods for rapid and cost-effective assessment of the biotransformation potential of very hydrophobic and potentially bioaccumulative chemicals in mammals are urgently needed for the ongoing global evaluation of the environmental behavior of commercial chemicals. We developed and tested a novel solvent-free, thin-film sorbent-phase in vitro dosing system to measure the in vitro biotransformation rates of very hydrophobic chemicals in male Sprague-Dawley rat liver S9 homogenates and compared the rates to those measured by conventional solvent-delivery dosing. The thin-film sorbent-phase dosing system using ethylene vinyl acetate coated vials was developed to eliminate the incomplete dissolution of very hydrophobic substances in largely aqueous liver homogenates, to determine biotransformation rates at low substrate concentrations, to measure the unbound fraction of substrate in solution, and to simplify chemical analysis by avoiding the difficult extraction of test chemicals from complex biological matrices. Biotransformation rates using sorbent-phase dosing were 2-fold greater than those measured using solvent-delivery dosing. Unbound concentrations of very hydrophobic test chemicals were found to decline with increasing S9 and protein concentrations, causing measured biotransformation rates to be independent of S9 or protein concentrations. The results emphasize the importance of specifying both protein content and unbound substrate fraction in the measurement and reporting of in vitro biotransformation rates of very hydrophobic substances, which can be achieved in a thin-film sorbent-phase dosing system.

Ameliorative effect of docosahexaenoic acid on 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced histological changes, oxidative stress, and DNA damage in rat liver

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant that leads to the development of hepatotoxicity. Docosahexaenoic acid (DHA) has been proposed to counteract oxidative stress and improve antioxidant status, and several studies suggest that supplementations with antioxidants can influence hepatotoxicity. The aim of the current study was to explore the role of DHA in modulating the toxicity of TCDD in the liver of Sprague-Dawley rats. Animals were assigned to four groups (n = 5): control (only dimethyl sulfoxide (DMSO)), 8 μg/kg body weight (b.w.) TCDD in DMSO solution; 250 mg/kg b.w. DHA and TCDD plus DHA; respectively. Rats were intraperitoneally administered their respective doses daily for 21 days. On day 21, the animals were killed, and then biochemical tests, pathological examination, and micronucleus (MN) assay were performed in the liver. Our results showed that the activities of antioxidant enzymes were significantly decreased and serious pathological findings were established in rats that received TCDD. Beside the rate of MNs in hepatocytes was increased after the treatment with dioxin. In rats treated with DHA alone, MNs were not changed and the activities of antioxidant enzymes were significantly increased. The presence of DHA with TCDD alleviated its pathological effects in hepatic tissue. DHA also prevented the suppression of antioxidant enzymes in the livers of animals exposed to TCDD and displayed a strong protective effect against MNs. It can be concluded that DHA has beneficial influences and could be able to antagonize TCDD toxicity in liver.

Influence of Co-Administered Danshensu on Pharmacokinetic Fate and Tissue Distribution of Paeonol in Rats

Cortex Moutan (root bark of Paeonia suffruticosa Andrew) and Radix Salviae miltiorrhizae (root and rhizome of Salvia miltiorrhiza Bunge) are two herbs widely used in traditional Chinese medicine (TCM) to treat cerebrovascular and cardiovascular diseases. In clinical practice, these two herbs are prescribed together. Studies on the pharmacokinetic interaction between the active constituents of these two herbs (paeonol and danshensu, respectively) can provide substantial foundation for understanding its mechanism and empirical evidence to support the clinical practice. A simple and sensitive high-performance liquid chromatographic (HPLC) method coupled with ultraviolet detector was developed for determination of paeonol in plasma and different tissues (heart, liver, spleen, lung, kidney, and brain) of male Sprague-Dawley rats. When co-administering danshensu, the peak plasma concentration of paeonol was decreased (p < 0.01), the mean residence time (MRT) was prolonged (p < 0.001), the volume of distribution (Vd/F) was increased (p < 0.001), and the concentrations of paeonol in heart, brain, and lung were dramatically increased (p < 0.01 or p < 0.001), compared with these values for rats administered paeonol alone. The results showed that the co-administration of danshensu could alter pharmacokinetic fate and tissue distribution of paeonol in rats, especially in heart and brain, providing substantial foundation for the investigation of the impact of danshensu on paeonol in clinical applications.

Cordycepin 고함유 동충하초(Cordyceps militaris JLM 0636)의 orotic acid 유발 흰쥐의 지방간 개선효과

The concentration of cordycepin produced by crossbred Cordyceps militaris JLM 0636 (CMα) was 7.42 mg/g dry weight, which was 7-fold higher than that of C. militaris (CM). However, cordycepin was not detected in Paecilomyces japonica (PJ). The improvement effects of CMα, CM and PJ on orotic acid (OA)-induced fatty liver in male Sprague-Dawley rats was investigated. Rats were randomly divided into five groups (n=6) based on five dietary categories: normal (N), OA control (C), OA plus 3% (w/w) PJ (PJ), OA plus 3% CM (CM), and OA plus 3% CMα (CMα). OA treatment induced the retardation of body weight gain and enlargement of the liver. The concentration of hepatic triglyceride was markedly increased by OA-feeding, whereas this rise was significantly reduced by simultaneous feeding of OA, PJ, CM, and CMα, and this phenomenon was more pronounced by cordycepin- enriched CMα. The contents of total lipid, triglyceride, and free fatty acid in the serum were significantly or slightly lower in the OA control group than those of the N group, but there were no significant differences among the OA treatment groups. The hepatocytes in the OA-induced fatty liver contained numerous large lipid droplets, but PJ, CM, and CMα feeding prevented the OA-induced lipid droplet accumulation in the hepatocytes. This effect was more pronounced in cordycepin-enriched CMα than in PJ or CM in OA treatment rats. Accordingly, cordycepin-enriched CMα could be an ideal candidate material as a dietary supplement in healthy functional foods to improve the effects of fatty liver.

Electromagnetic thermotherapy using fine needles for hepatoma treatment

Background and aims Hepatocellular carcinoma can be treated with heat-based therapies, especially radiofrequency ablation (RFA). However, RFA has limited efficacy and is quite expensive. We designed a new system using fine needles combined with an alternating magnetic field to generate hyperthermia for the treatment of hepatocellular carcinoma in a rat hepatoma model. Our aims are to assess the efficacy of our method and determine survival up to 30 days. Methods An N1-S1 cell line was inoculated into the livers of Sprague-Dawley rats, generating tumors after 14 days. The animals were randomized into 5 groups and treated after laparotomy either with normal saline (group I), iron oxide nanoparticles (group II), fine needles (group III), fine needles and iron oxide nanoparticles combined (group IV) or self-designed two-part needles placed under ultrasonographic guidance percutaneously (group V). Every rat was placed in an alternating magnetic field. The temperature in the treatment area was maintained between 55 and 60 °C. At day 30 after treatment, tumor volumes and mortality were assessed and histology samples were studied. Results Tumor volumes were significantly reduced and survival rate was prolonged in groups III, IV and V versus groups I and II ( P < 0.05). On pathological examination, groups III, IV and V presented obvious necrosis, apoptosis, calcifications and inflammatory changes in the treatment area. Conclusion Our study demonstrates that hyperthermia generated by fine stainless-steel needles combined with an alternating magnetic field effectively inhibits hepatoma growth in rats and prolongs their survival. Further, this method can be applied percutaneously under ultrasonographic guidance.