OBJECTIVES: To explore the effects of hypoxic and hypobaric conditions on blood gas and erythrocyte-related indicators in rats. METHODS: SD male rats were exposed to low-pressure hypoxic conditions simulating an altitude of 6500 m in a small or a large experimental cabin. Abdominal aortic blood samples were collected and blood gas indicators, red blood cells (RBCs) count, and hemoglobin (Hb) content were measured. The effects of exposure to different hypoxia times, different hypoxia modes, normal oxygen recovery after hypoxia, and re-hypoxia after hypoxia preconditioning on blood gas indicators, RBCs count and Hb content were investigated. RESULTS: The effect of blood gas indicators was correlated with the length of exposure time of hypoxia and the reoxygenation after leaving the cabin. Hypoxia caused acid-base imbalance and its severity was associated with the duration of hypoxia; hypoxia also led to an increase in RBCs count and Hb content, and the increase was also related to the time exposed to hypoxia. The effects of reoxygenation on acid-base imbalance in rats caged in a small animal cabin were more severe that those in a large experimental cabin. Acetazolamide alleviated the effects of reoxygenation after leaving the cabin. Different hypoxia modes and administration of acetazolamide had little effect on RBCs count and Hb content. Normal oxygen recovery can alleviate the reoxygenation and acid-base imbalance of hypoxic rats after leaving the cabin and improve the increase in red blood cell and hemoglobin content caused by hypoxia. The improvement of hypoxia preconditioning on post hypoxia reoxygenation is not significant, but it can alleviate the acid-base imbalance caused by hypoxia in rats and to some extent improve the increase in red blood cell and hemoglobin content caused by hypoxia. CONCLUSIONS Due to excessive ventilation and elevated RBCs count and Hb content after hypoxia reoxygenation, oxygen partial pressure and other oxygenation indicators in hypoxic rats are prone to become abnormal, while blood gas acid-base balance indicators are relatively stable, which are more suitable for evaluating the degree of hypoxia injury and related pharmacological effects in rats.
Rats ; Animals ; Male ; Acetazolamide ; Hypoxia ; Oxygen ; Erythrocytes ; Hemoglobins ; Acid-Base Imbalance

ObjectiveTo explore the activating effects of ten important effective components in seven medicinal and edible substances on human pregnane X receptor （PXR）， including Glycyrrhizae Radix et Rhizoma （liquiritin and glycyrrhizic acid）， Houttuyniae Herba （quercetin and houttuyfonate）， Prunellae Spica （rosmarinic acid）， Cassiae Semen （aurantio-obtusin）， Poria （pachymic acid）， Lilii Bulbus （Lilium brownii saponin and colchicine）， and Lycii Fructus （Lycium barbarum polysaccharide） and screen potentially toxic components. MethodCell counting kit-8 （CCK-8） assay was used to investigate the cytotoxic effect of liquiritin， glycyrrhizic acid， quercetin， houttuyfonate， rosmarinic acid， pachymic acid， aurantio-obtusin， and colchicine （10， 20， and 50 μmol·L^-1）， and L. brownii saponin and L. barbarum polysaccharide （10， 20， and 50 mg·L^-1） on normal human hepatocyte cell line （L02）. The release of lactate dehydrogenase （LDH） in L02 cells after drug treatments was detected by the biochemical analyzer. The apoptosis induced by ten effective components was explored by Hoechst 33342 staining. The secreted luciferase reporter system was used to co-transfect the PXR expression vector and reporter gene vector containing cytochrome P450 3A4 （CYP3A4） transcriptional regulatory region into L02 cells， with 10 μmol·L^-1 rifampicin （RIF） as a positive control. After treated with liquiritin， glycyrrhizic acid， quercetin， houttuyfonate， rosmarinic acid， aurantio-obtusin， pachymic acid， and colchicine （5， 10， and 20 μmol·L^-1） and L. brownii saponin and L. barbarum polysaccharide （5， 10， and 20 mg·L^-1） for 24 h， the cells were tested for secreted luciferase activity. ResultCompared with the control group， colchicine， L. brownii saponin， and quercetin decreased the cell viability （P<0.05， P<0.01）. Compared with the control group， quercetin， rosmarinic acid， glycyrrhizic acid， colchicine， aurantio-obtusin， and pachymic acid increased the release rate of LDH in L02 cells （P<0.05， P<0.01）. The proportion of hyperchromatic nuclei increased gradually after rosmarinic acid， liquiritin， and L. barbarum polysaccharide treatments as compared with the control group （P<0.05， P<0.01）. In terms of co-transfection of pcDNA3.1-PXR and pGLuc-CYP3A4 into L02 cells， compared with the control group， aurantio-obtusin and pachymic acid showed activating effects on PXR （P<0.05）， whereas liquiritin and glycyrrhizic acid showed inhibitory effects （P<0.05）. ConclusionThe findings suggest that when medicinal and edible substances are taken for a long time， attention should be paid to their influence on drug-metabolizing enzymes and possible interactions， so as to improve their safety.

Radiation-induced skin injury refers to the acute and chronic skin damage caused when skin is exposed to radiation. Radiation-induced skin damage may be created by nuclear disaster, radiation accident, radiation therapy, occupational exposure and so on. Approximately 95% of patients receiving radiotherapy will eventually develop into radiation-induced dermatitis during or after the treatment. As a consequence, how to appropriately prevent and remedy radiation-induced skin injury is of great practical significance. According to traditional Chinese medicine, radiation-induced skin injury belongs to fire, heat and toxin, blocking Qi and blood, injuring the muscle surface, affecting the distribution of Qi, blood and body fluid in the body, and damaging the function of viscera. This paper summarizes the cognition and development of traditional Chinese medicine theory of radiation-induced skin injury, as well as the research progress of internal and external treatment of traditional Chinese medicine, so as to provide a basis for the research and treatment of radiation-induced skin injury with traditional Chinese medicine.

Doxorubicin (DOX) is a highly effective chemotherapeutic agent; however, the dose-dependent cardiotoxicity associated with DOX significantly limits its clinical application. In the present study, we investigated whether Rb1 could prevent DOX-induced apoptosis in H9C2 cells via aryl hydrocarbon receptor (AhR). H9C2 cells were treated with various concentrations (−μM) of Rb1. AhR, CYP1A protein and mRNA expression were quantified with Western blot and real-time PCR analyses. We also evaluated the expression levels of caspase-3 to assess the anti-apoptotic effects of Rb1. Our results showed that Rb1 attenuated DOX-induced cardiomyocytes injury and apoptosis and reduced caspase-3 and caspase-8, but not caspase-9 activity in DOX-treated H9C2 cells. Meanwhile, pre-treatment with Rb1 decreased the expression of caspase-3 and PARP in the protein levels, with no effects on cytochrome c, Bax, and Bcl-2 in DOX-stimulated cells. Rb1 markedly decreased the CYP1A1 and CYP1A2 expression induced by DOX. Furthermore, transfection with AhR siRNA or pre-treatment with AhR antagonist CH-223191 significantly inhibited the ability of Rb1 to decrease the induction of CYP1A, as well as caspase-3 protein levels following stimulation with DOX. In conclusion, these findings indicate that AhR plays an important role in the protection of Ginsenoside Rb1 against DOX-triggered apoptosis of H9C2 cells.
Apoptosis* ; Blotting, Western ; Cardiotoxicity ; Caspase 3 ; Caspase 8 ; Caspase 9 ; Cytochrome P-450 CYP1A1 ; Cytochrome P-450 CYP1A2 ; Cytochromes c ; Doxorubicin ; Myocytes, Cardiac ; Real-Time Polymerase Chain Reaction ; Receptors, Aryl Hydrocarbon* ; RNA, Messenger ; RNA, Small Interfering ; Transfection

Tanshinone IIA (Tan IIA) is a pharmacologically active substance extracted from the rhizome of Salvia miltiorrhiza Bunge (also known as the Chinese herb Danshen), and is widely used to treat atherosclerosis. The pregnane X receptor (PXR) is a nuclear receptor that is a key regulator of xenobiotic and endobiotic detoxification. Tan IIA is an efficacious PXR agonist that has a potential protective effect on endothelial injuries induced by xenobiotics and endobiotics via PXR activation. Previously numerous studies have demonstrated the possible effects of Tan IIA on human umbilical vein endothelial cells, but the further mechanism for its exerts the protective effect is not well established. To study the protective effects of Tan IIA against hydrogen peroxide (H₂O₂) in human umbilical vein endothelial cells (HUVECs), we pretreated cells with or without different concentrations of Tan IIA for 24 h, then exposed the cells to 400 μM H₂O₂ for another 3 h. Therefore, our data strongly suggests that Tan IIA may lead to increased regeneration of glutathione (GSH) from the glutathione disulfide (GSSG) produced during the GSH peroxidase-catalyzed decomposition of H₂O₂ in HUVECs, and the PXR plays a significant role in this process. Tan IIA may also exert protective effects against H₂O₂-induced apoptosis through the mitochondrial apoptosis pathway associated with the participation of PXR. Tan IIA protected HUVECs from inflammatory mediators triggered by H₂O₂ via PXR activation. In conclusion, Tan IIA protected HUVECs against H₂O₂-induced cell injury through PXR-dependent mechanisms.
Apoptosis ; Asian Continental Ancestry Group ; Atherosclerosis ; Endothelial Cells* ; Glutathione ; Glutathione Disulfide ; Human Umbilical Vein Endothelial Cells ; Humans ; Hydrogen Peroxide ; Inflammation ; Oxidative Stress ; Regeneration ; Rhizome ; Salvia miltiorrhiza ; Triacetoneamine-N-Oxyl ; Xenobiotics

OBJECTIVE To study the cardiotoxicity of ophiopogonin D′(OPD′) for rat H9c2 cardio? myocytes. METHODS H9c2 cells were exposed to OPD′ 0.1, 1, 5, 10, 20, 25 and 50 μmol·L-1 for 24 h. Cell viability was examined by MTS assay, and the morphological changes in H9c2 cells were quanti? fied. The cell nucleus injury was examined by high content immune fluorescence screening and the morphological changes were observed under a fluorescence microscope. After treatment with OPD′ 0.1, 1, 5 and 10 μmol·L- 1 for 24 h, the effect on reactive oxygen species (ROS), mitochondrial mem? brane potential(MMP) and apoptosis was detected by flow cytometry. RESULTS The viability was sig? nificantly reduced following exposure to OPD′ 0.1, 1, 5, 10, 20, 25 and 50 μmol·L- 1 (P<0.05,P<0.01). The IC50 value was 9.9 μmol ·L- 1 and cell shrinkage and apoptosis occurred. The levels of ROS and apoptosis rate of H9c2 cells were significantly increased after exposure to OPD′ 0.1, 1, 5 and 10 μmol·L-1 for 24 h (P<0.05,P<0.01) and MMP markedly declined (P<0.05,P<0.01). CONCLUSION OPD′ has significent cytotoxicity on H9c2 cells. It may be related to inducing apopotsis pathways.

OBJECTIVE To investigate the hepatotoxicity mechanisms of ethanol extract of Radix Polygoni Multiflori (RPM) and Radix Polygoni Multiflori Praeparata (RPMP) by high-content screen assay.METHODS HepG2 cells were treated with RPM (10,25,50,100,200 and 300 mg·L-1) and RPMP (10,50,100,300,600 and 1200 mg· L-1) for 3-24 h,respectively.The cell viability was detected by a CellTiter-GloTM luminescent cell viability assay kit.Cell count,reactive oxygen species (ROS),mitochondrial membrane potential (MMP),glutathione (GSH),superoxide dismutase 2 (SOD2),activating transcription factor 4 (ATF4),apoptosis,and cell cycles were investigated by high-content screen assay.Besides,SOD2 and ATF4 levels were confirmed by Western blotting.RESULTS RPM 300 mg· L-1 showed nearly 48 ％ reduction in cell viability compared with cell control (P＜0.01),while RPMP had no significant effect at the same concentration.Both RPM and RPMP decreased the level of MMP (P＜0.05) but incresed levels of GSH,ROS,SOD2 and ATF4 significantly (P＜0.05).Besides,RPM 200 mg· L-1 significantly increased the expression of SOD2 (P＜0.05) at 3 h by high-content screen assay,and the enhanced expression of ATF4 was shown at 6 h (P＜0.05).RPMP 300 mg· L-1 markedly increased the expression of ATF4 at 6 h (P＜0.05),while the expression of SOD2 significantly increased at 24 h (P＜0.05).CONCLUSION Both RPM and RPMP have some cytotoxicity,and the cytotoxicity of RPM is stronger than that of RPMP.The hepatotoxicity mechanisms of RPM and RPMP may be related to cell apoptosis caused by long-term oxidative stress and endoplasmic reticulum stress.

OBJCTIVE To investigate the protective effect of ferulic acid (FA) on lipopolysaccharide (LPS)-induced damage to PC12 cells and hippocampal neurons in Sprague-Dawley (SD) rats and its potential mechanisms. METHODS ① in vitro study:PC12 cells were pretreated with FA 2.5-40 μmol · L-1 for 12 h and treated with LPS for another 8 h. CCK-8 kit was used to test PC12 cell viability. Inflammatory cytokines tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)were de?tected by ELISA kits. Laser scanning confocal microscopy was performed to measure F-actin expres?sion in the cells. ②in vivo study:FA 25,50 and 100 mg · kg-1 was ip given to Sprague-Dawley(SD) rats once a day for 35 d,and from the 29th day,ip co-administered with LPS(0.2 mg · kg-1)for 7 d. Immunohistochemistry method was used to determine protein expression of phophodiestera 4B (PDE4B)in the hippocampus of rats. The protein expression of cAMP response element-binding protein (CREB) and phospho CREB (p-CREB) was determined by Western blotting. RESULTS In the in vitro study,compared with LPS group,cell viability was significantly increased in FA 10,20 and 40μmol·L-1 groups(P<0.05),while the production of inflammatory cytokines TNF-α and IL-1β decreased(P<0.05). The structure and distribution of cytoskeletal protein F-actin were ameliorated markedly in PC12 cells. In the in vivo study,hematoxylin-eosin(HE)staining showed that pretreatment with FA(50 and 100 mg·kg-1) alleviated the damage to the hippocampus induced by LPS in SD rats. Immunohistochemistry showed that FA(50 and 100 mg·kg-1)pretreatment effectively prevented LPS-induced up-regulation of PDE4B expression in the hippocampus of rats(P<0.05). Western blotting analysis showed that the inhibitory effects on the protein expressions of CREB and p-CREB induced by LPS were altered by FA(50 and 100 mg · kg-1)pretreatment(P<0.05). CONCLUSION FA can protect against LPS induced damage to PC12 cells and hippocampal neurons of rats. The resistant effect on neuron-inflammation of FA may be conferred by inhibiting LPS-induced up-regulation of PDE4B and stimulating signaling pathways of cAMP/CREB.

Aim To investigate the induction effect of ginsenoside Rc, Re, Rf and Rg1 on CYP1A1, and further validate the role of aryl hydrocarbon receptor in CYP1A1 expression. Methods Dual luciferase re-porter gene system was performed. Four kinds of gin-senoside were screened for aryl hydrocarbon receptor activation by reporter assays, and TCDD as the positive control. Further with different concentrations of ginsen-oside Rc, Re, Rf and Rg1 treated on LS174T cells, RNA and total protein were extracted to detect the reg-ulating effect of ginsenosides on CYP1 A1 mRNA and protein expression with Real-time PCR and Western blot technology respectively. Results Reporter gene screening showed that the ginsenoside Rc, Re, Rf and Rg1 could activate AhR and had potential effects on the induction of CYP1A1 enzyme. Meanwhile, dose-de-pendent induction of the gene expression were observed in response to ginsenoside Rc, Re, Rf and Rg1 and the levels of CYP1 A1 protein expression were increased by ginsenoside Rc, Re, Rf and Rg1 in varying de-grees. Conclusion Ginsenoside Rc, Re, Rf and Rg1 can up-regulate the gene and protein expression of CYP1 A1 possibly via the AhR-mediated CYP1 A1 path-way.