1.Electroacupuncture Promotes Functional Recovery after Facial Nerve Injury in Rats by Regulating Autophagy via GDNF and PI3K/mTOR Signaling Pathway.
Jun-Peng YAO ; Xiu-Mei FENG ; Lu WANG ; Yan-Qiu LI ; Zi-Yue ZHU ; Xiang-Yun YAN ; Yu-Qing YANG ; Ying LI ; Wei ZHANG
Chinese journal of integrative medicine 2024;30(3):251-259
OBJECTIVE:
To explore the mechanism of electroacupuncture (EA) in promoting recovery of the facial function with the involvement of autophagy, glial cell line-derived neurotrophic factor (GDNF), and phosphatidylinositol-3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway.
METHODS:
Seventy-two male Sprague-Dawley rats were randomly allocated into the control, sham-operated, facial nerve injury (FNI), EA, EA+3-methyladenine (3-MA), and EA+GDNF antagonist groups using a random number table, with 12 rats in each group. An FNI rat model was established with facial nerve crushing method. EA intervention was conducted at Dicang (ST 4), Jiache (ST 6), Yifeng (SJ 17), and Hegu (LI 4) acupoints for 2 weeks. The Simone's 10-Point Scale was utilized to monitor the recovery of facial function. The histopathological evaluation of facial nerves was performed using hematoxylin-eosin (HE) staining. The levels of Beclin-1, light chain 3 (LC3), and P62 were detected by immunohistochemistry (IHC), immunofluorescence, and reverse transcription-polymerase chain reaction, respectively. Additionally, IHC was also used to detect the levels of GDNF, Rai, PI3K, and mTOR.
RESULTS:
The facial functional scores were significantly increased in the EA group than the FNI group (P<0.05 or P<0.01). HE staining showed nerve axons and myelin sheaths, which were destroyed immediately after the injury, were recovered with EA treatment. The expressions of Beclin-1 and LC3 were significantly elevated and the expression of P62 was markedly reduced in FNI rats (P<0.01); however, EA treatment reversed these abnormal changes (P<0.01). Meanwhile, EA stimulation significantly increased the levels of GDNF, Rai, PI3K, and mTOR (P<0.01). After exogenous administration with autophagy inhibitor 3-MA or GDNF antagonist, the repair effect of EA on facial function was attenuated (P<0.05 or P<0.01).
CONCLUSIONS
EA could promote the recovery of facial function and repair the facial nerve damages in a rat model of FNI. EA may exert this neuroreparative effect through mediating the release of GDNF, activating the PI3K/mTOR signaling pathway, and further regulating the autophagy of facial nerves.
Rats
;
Male
;
Animals
;
Rats, Sprague-Dawley
;
Electroacupuncture
;
Phosphatidylinositol 3-Kinase/metabolism*
;
Facial Nerve Injuries/therapy*
;
Phosphatidylinositol 3-Kinases/metabolism*
;
Beclin-1
;
Glial Cell Line-Derived Neurotrophic Factor
;
Signal Transduction
;
TOR Serine-Threonine Kinases/metabolism*
;
Autophagy
;
Mammals/metabolism*
2.The combination of EGCG with warfarin reduces deep vein thrombosis in rabbits through modulating HIF-1α and VEGF via the PI3K/AKT and ERK1/2 signaling pathways.
Yan LI ; Jing-Ping GE ; Ke MA ; Yuan-Yuan YIN ; Juan HE ; Jian-Ping GU
Chinese Journal of Natural Medicines (English Ed.) 2022;20(9):679-690
Deep venous thrombosis (DVT) poses a major challenge to public health worldwide. Endothelial cell injury evokes inflammatory and oxidative responses that contribute to thrombus formation. Tea polyphenol (TP) in the form of epigallocatechin-3-gallate (EGCG) has anti-inflammatory and oxidative effect that may ameliorate DVT. However, the precise mechanism remains incompletely understood. The current study was designed to investigate the anti-DVT mechanism of EGCG in combination with warfarin (an oral anticoagulant). Rabbits were randomly divided into five groups. A DVT model of rats was established through ligation of the inferior vena cava (IVC) and left common iliac vein, and the animals were orally administered with EGCG, warfarin, or vehicle for seven days. In vitro studies included pretreatment of human umbilical vein endothelial cells (HUVECs) with different concentrations of EGCG for 2 h before exposure to hydrogen peroxide. Thrombus weight and length were examined. Histopathological changes were observed by hematoxylin-eosin staining. Blood samples were collected for detecting coagulation function, including thrombin and prothrombin times, activated partial thromboplastin time, and fibrinogen levels. Protein expression in thrombosed IVCs and HUVECs was evaluated by Western blot, immunohistochemical analysis, and/or immunofluorescence staining. RT-qPCR was used to determine the levels of AGTR-1 and VEGF mRNA in IVCs and HUVECs. The viability of HUVECs was examined by CCK-8 assay. Flow cytometry was performed to detect cell apoptosis and ROS generation was assessed by 2',7'-dichlorofluorescein diacetate reagent. In vitro and invivo studies showed that EGCG combined with warfarin significantly reduced thrombus weight and length, and apoptosis in HUVECs. Our findings indicated that the combination of EGCG and warfarin protects HUVECs from oxidative stress and prevents apoptosis. However, HIF-1α silencing weakened these effects, which indicated that HIF-1α may participate in DVT. Furthermore, HIF-1α silencing significantly up-regulated cell apoptosis and ROS generation, and enhanced VEGF expression and the activation of the PI3K/AKT and ERK1/2 signaling pathways. In conclusion, our results indicate that EGCG combined with warfarin modifies HIF-1α and VEGF to prevent DVT in rabbits through anti-inflammation via the PI3K/AKT and ERK1/2 signaling pathways.
Animals
;
Anticoagulants/pharmacology*
;
Catechin/analogs & derivatives*
;
Eosine Yellowish-(YS)/pharmacology*
;
Fibrinogen/pharmacology*
;
Hematoxylin/pharmacology*
;
Human Umbilical Vein Endothelial Cells
;
Humans
;
Hydrogen Peroxide/pharmacology*
;
Hypoxia-Inducible Factor 1, alpha Subunit/metabolism*
;
MAP Kinase Signaling System
;
Phosphatidylinositol 3-Kinases/metabolism*
;
Polyphenols/pharmacology*
;
Proto-Oncogene Proteins c-akt/metabolism*
;
RNA, Messenger
;
Rabbits
;
Rats
;
Reactive Oxygen Species/metabolism*
;
Signal Transduction
;
Sincalide/pharmacology*
;
Tea
;
Thrombin/pharmacology*
;
Vascular Endothelial Growth Factor A/metabolism*
;
Venous Thrombosis/pathology*
;
Warfarin/pharmacology*
3.Bone marrow-derived mesenchymal stem cells modulate autophagy in RAW264.7 macrophages via the phosphoinositide 3-kinase/protein kinase B/heme oxygenase-1 signaling pathway under oxygen-glucose deprivation/restoration conditions.
Chinese Medical Journal 2021;134(6):699-707
BACKGROUND:
Autophagy of alveolar macrophages is a crucial process in ischemia/reperfusion injury-induced acute lung injury (ALI). Bone marrow-derived mesenchymal stem cells (BM-MSCs) are multipotent cells with the potential for repairing injured sites and regulating autophagy. This study was to investigate the influence of BM-MSCs on autophagy of macrophages in the oxygen-glucose deprivation/restoration (OGD/R) microenvironment and to explore the potential mechanism.
METHODS:
We established a co-culture system of macrophages (RAW264.7) with BM-MSCs under OGD/R conditions in vitro. RAW264.7 cells were transfected with recombinant adenovirus (Ad-mCherry-GFP-LC3B) and autophagic status of RAW264.7 cells was observed under a fluorescence microscope. Autophagy-related proteins light chain 3 (LC3)-I, LC3-II, and p62 in RAW264.7 cells were detected by Western blotting. We used microarray expression analysis to identify the differently expressed genes between OGD/R treated macrophages and macrophages co-culture with BM-MSCs. We investigated the gene heme oxygenase-1 (HO-1), which is downstream of the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway.
RESULTS:
The ratio of LC3-II/LC3-I of OGD/R treated RAW264.7 cells was increased (1.27 ± 0.20 vs. 0.44 ± 0.08, t = 6.67, P < 0.05), while the expression of p62 was decreased (0.77 ± 0.04 vs. 0.95 ± 0.10, t = 2.90, P < 0.05), and PI3K (0.40 ± 0.06 vs. 0.63 ± 0.10, t = 3.42, P < 0.05) and p-Akt/Akt ratio was also decreased (0.39 ± 0.02 vs. 0.58 ± 0.03, t = 9.13, P < 0.05). BM-MSCs reduced the LC3-II/LC3-I ratio of OGD/R treated RAW264.7 cells (0.68 ± 0.14 vs. 1.27 ± 0.20, t = 4.12, P < 0.05), up-regulated p62 expression (1.10 ± 0.20 vs. 0.77 ± 0.04, t = 2.80, P < 0.05), and up-regulated PI3K (0.54 ± 0.05 vs. 0.40 ± 0.06, t = 3.11, P < 0.05) and p-Akt/Akt ratios (0.52 ± 0.05 vs. 0.39 ± 0.02, t = 9.13, P < 0.05). A whole-genome microarray assay screened the differentially expressed gene HO-1, which is downstream of the PI3K/Akt signaling pathway, and the alteration of HO-1 mRNA and protein expression was consistent with the data on PI3K/Akt pathway.
CONCLUSIONS
Our results suggest the existence of the PI3K/Akt/HO-1 signaling pathway in RAW264.7 cells under OGD/R circumstances in vitro, revealing the mechanism underlying BM-MSC-mediated regulation of autophagy and enriching the understanding of potential therapeutic targets for the treatment of ALI.
Apoptosis
;
Autophagy
;
Bone Marrow
;
Glucose
;
Heme Oxygenase-1/metabolism*
;
Macrophages/metabolism*
;
Mesenchymal Stem Cells/metabolism*
;
Oxygen
;
Phosphatidylinositol 3-Kinase
;
Phosphatidylinositol 3-Kinases/metabolism*
;
Proto-Oncogene Proteins c-akt/metabolism*
;
Signal Transduction
4.Panax Notoginseng Saponin Attenuates Gastric Mucosal Epithelial Cell Injury Induced by Dual Antiplatelet Drugs through COX and PI3K/Akt/ VEGF-GSK-3β-RhoA Network Pathway.
Ming-Ming WANG ; Mei XUE ; Zhong-Hai XIN ; Yan-Hui WANG ; Rui-Jie LI ; Hong-Yan JIANG ; Da-Zhuo SHI
Chinese journal of integrative medicine 2021;27(11):819-824
OBJECTIVE:
To elucidate the underlying mechanism of Panax notoginseng saponin (PNS) on gastric epithelial cell injury and barrier dysfunction induced by dual antiplatelet (DA).
METHODS:
Human gastric mucosal epithelial cell (GES-1) was cultured and divided into 4 groups: a control, a DA, a PNS+DA and a LY294002+PNS+DA group. GES-1 apoptosis was detected by flow cytometry, cell permeability were detected using Transwell, level of prostaglandins E2 (PGE2), 6-keto-prostaglandin F1α (6-keto-PGF1α) and vascular endothelial growth factor (VEGF) in supernatant were measured by enzyme linked immunosorbent assay (ELISA), expression of phosphatidylinositide 3-kinase (PI3K), phosphorylated-PI3K (p-PI3K), Akt, phosphorylated-Akt (p-Akt), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), glycogen synthase kinase-3β (GSK-3β) and Ras homolog gene family member A (RhoA) were measured by Western-blot.
RESULTS:
DA induced apoptosis and hyper-permeability in GES-1, reduced supernatant level of PGE2, 6-keto-PGF1α and VEGF (P<0.05). Addition of PNS reduced the apoptosis of GES-1 caused by DA, restored the concentration of PGE2, 6-keto-PGF1α and VEGF (P<0.05). In addition, PNS attenuated the alteration of COX-1 and COX-2 expression induced by DA, up-regulated p-PI3K/p-Akt, down-regulated RhoA and GSK-3β. LY294002 mitigated the effects of PNS on cell apoptosis, cell permeability, VEGF concentration, and expression of RhoA and GSK-3β significantly.
CONCLUSIONS
PNS attenuates the suppression on COX/PG pathway from DA, alleviates DA-induced GES-1 apoptosis and barrier dysfunction through PI3K/Akt/ VEGF-GSK-3β-RhoA network pathway.
Cyclooxygenase 1
;
Epithelial Cells/metabolism*
;
Glycogen Synthase Kinase 3 beta
;
Humans
;
Panax notoginseng
;
Phosphatidylinositol 3-Kinases/metabolism*
;
Platelet Aggregation Inhibitors
;
Proto-Oncogene Proteins c-akt/metabolism*
;
Saponins/pharmacology*
;
Vascular Endothelial Growth Factor A
;
rhoA GTP-Binding Protein
5.Increased glucose metabolism and alpha-glucosidase inhibition in Cordyceps militaris water extract-treated HepG2 cells.
Dae Jung KIM ; Yun Hwan KANG ; Kyoung Kon KIM ; Tae Woo KIM ; Jae Bong PARK ; Myeon CHOE
Nutrition Research and Practice 2017;11(3):180-189
BACKGROUND/OBJECTIVES: Recent living condition improvements, changes in dietary habits, and reductions in physical activity are contributing to an increase in metabolic syndrome symptoms including diabetes and obesity. Through such societal developments, humankind is continuously exposed to metabolic diseases such as diabetes, and the number of the victims is increasing. This study investigated Cordyceps militaris water extract (CMW)-induced glucose uptake in HepG2 cells and the effect of CMW treatment on glucose metabolism. MATERIALS/METHODS: Colorimetric assay kits were used to determine the glucokinase (GK) and pyruvate dehydrogenase (PDH) activities, glucose uptake, and glycogen content. Either RT-PCR or western blot analysis was performed for quantitation of glucose transporter 2 (GLUT2), hepatocyte nuclear factor 1 alpha (HNF-1α), phosphatidylinositol 3-kinase (PI3k), protein kinase B (Akt), phosphorylated AMP-activated protein kinase (pAMPK), phosphoenolpyruvate carboxykinase, GK, PDH, and glycogen synthase kinase 3 beta (GSK-3β) expression levels. The α-glucosidase inhibitory activities of acarbose and CMW were evaluated by absorbance measurement. RESULTS: CMW induced glucose uptake in HepG2 cells by increasing GLUT2 through HNF-1α expression stimulation. Glucose in the cells increased the CMW-induced phosphorylation of AMPK. In turn, glycolysis was stimulated, and glyconeogenesis was inhibited. Furthermore, by studying the mechanism of action of PI3k, Akt, and GSK-3β, and measuring glycogen content, the study confirmed that the glucose was stored in the liver as glycogen. Finally, CMW resulted in a higher level of α-glucosidase inhibitory activity than that from acarbose. CONCLUSION: CMW induced the uptake of glucose into HepG2 cells, as well, it induced metabolism of the absorbed glucose. It is concluded that CMW is a candidate or potential use in diabetes prevention and treatment.
Acarbose
;
alpha-Glucosidases*
;
AMP-Activated Protein Kinases
;
Blotting, Western
;
Cordyceps*
;
Food Habits
;
Glucokinase
;
Glucose Transport Proteins, Facilitative
;
Glucose*
;
Glycogen
;
Glycogen Synthase Kinase 3
;
Glycolysis
;
Hep G2 Cells*
;
Hepatocyte Nuclear Factor 1-alpha
;
Hypoglycemic Agents
;
Liver
;
Metabolic Diseases
;
Metabolism*
;
Motor Activity
;
Obesity
;
Oxidoreductases
;
Phosphatidylinositol 3-Kinase
;
Phosphoenolpyruvate
;
Phosphorylation
;
Proto-Oncogene Proteins c-akt
;
Pyruvic Acid
;
Social Conditions
;
Water*
6.Garcinia xanthochymus extract protects PC12 cells from HO-induced apoptosis through modulation of PI3K/AKT and NRF2/HO-1 pathways.
Jing XU ; Sheng GAN ; Jun LI ; De-Bing WAND ; Yu CHEN ; Xin HU ; Guang-Zhong YANG
Chinese Journal of Natural Medicines (English Ed.) 2017;15(11):825-833
The aim of the present study was to investigate the protective effects and underlying mechanisms of Garcinia xanthochymus, a perennial medicinal plant native to Yunnan, China, against HO-induced oxidative damage in rat pheochromacytoma PC12 cells. Preincubation of PC12 cells with fruit EtOAc fraction (fruit-EFr., 12.5-50 µmol·L) of G. xanthochymus for 24 h prior to HO exposure markedly improved cell viability and increased the activities of antioxidant enzymes (superoxide dismutase, catalase, and heme oxygenase-1 [HO-1]), prevented lactate dehydrogenase release and lipid peroxidation malondialdehyde production, attenuated the decrease of matrix metalloproteinases (MMP), and scavenged reactive oxygen species (ROS). Fruit-EFr. also reduced BAX and cytochrome C expression and improved BCL-2 expression, thereby decreasing the ratio of BAX to BCL-2. Fruit-EFr. activated the nuclear translocation of NRF2 to increase HO-1 and induced the phosphorylation of AKT. Its cytoprotective effect was abolished by LY294002, a specific inhibitor of PI3K. Taken together, the above findings suggested that fruit-EFr.of G. xanthochymus could enhance cellular antioxidant defense capacity, at least in part, through upregulating HO-1 expression and activating the PI3K/AKT pathway and that it could suppress HO-induced oxidative damage via PI3K/AKT and NRF2/HO-1 signaling pathways.
Animals
;
Antioxidants
;
metabolism
;
pharmacology
;
Apoptosis
;
drug effects
;
Biological Transport
;
Cell Survival
;
Cytochromes c
;
metabolism
;
Fruit
;
Garcinia
;
Heme Oxygenase-1
;
metabolism
;
Hydrogen Peroxide
;
NF-E2-Related Factor 2
;
metabolism
;
Oxidative Stress
;
drug effects
;
PC12 Cells
;
Phosphatidylinositol 3-Kinase
;
metabolism
;
Phosphatidylinositol 3-Kinases
;
Phosphorylation
;
Plant Extracts
;
pharmacology
;
Protective Agents
;
pharmacology
;
Proto-Oncogene Proteins c-akt
;
metabolism
;
Proto-Oncogene Proteins c-bcl-2
;
metabolism
;
Rats
;
Signal Transduction
;
bcl-2-Associated X Protein
;
metabolism
7.Anti-Proliferative Effects of Rutin on OLETF Rat Vascular Smooth Muscle Cells Stimulated by Glucose Variability.
Sung Hoon YU ; Jae Myung YU ; Hyung Joon YOO ; Seong Jin LEE ; Dong Hyun KANG ; Young Jung CHO ; Doo Man KIM
Yonsei Medical Journal 2016;57(2):373-381
PURPOSE: Proliferation of vascular smooth muscle cells (VSMCs) plays a crucial role in atherosclerosis. Rutin is a major representative of the flavonol subclass of flavonoids and has various pharmacological activities. Currently, data are lacking regarding its effects on VSMC proliferation induced by intermittent hyperglycemia. Here, we demonstrate the effects of rutin on VSMC proliferation and migration according to fluctuating glucose levels. MATERIALS AND METHODS: Primary cultures of male Otsuka Long-Evans Tokushima Fatty (OLETF) rat VSMCs were obtained from enzymatically dissociated rat thoracic aortas. VSMCs were incubated for 72 h with alternating normal (5.5 mmol/L) and high (25.0 mmol/L) glucose media every 12 h. Proliferation and migration of VSMCs, the proliferative molecular pathway [including p44/42 mitogen-activated protein kinases (MAPK), mitogen-activated protein kinase kinase 1/2 (MEK1/2), p38 MAPK, phosphoinositide 3-kinase (PI3K), c-Jun N-terminal protein kinase (JNK), nuclear factor kappa B (NF-kappaB), and Akt], the migratory pathway (big MAPK 1, BMK1), reactive oxygen species (ROS), and apoptotic pathway were analyzed. RESULTS: We found enhanced proliferation and migration of VSMCs when cells were incubated in intermittent high glucose conditions, compared to normal glucose. These effects were lowered upon rutin treatment. Intermittent treatment with high glucose for 72 h increased the expression of phospho-p44/42 MAPK (extracellular signal regulated kinase 1/2, ERK1/2), phospho-MEK1/2, phospho-PI3K, phospho-NF-kappaB, phospho-BMK1, and ROS, compared to treatment with normal glucose. These effects were suppressed by rutin. Phospho-p38 MAPK, phospho-Akt, JNK, and apoptotic pathways [B-cell lymphoma (Bcl)-xL, Bcl-2, phospho-Bad, and caspase-3] were not affected by fluctuations in glucose levels. CONCLUSION: Fluctuating glucose levels increased proliferation and migration of OLETF rat VSMCs via MAPK (ERK1/2), BMK1, PI3K, and NF-kappaB pathways. These effects were inhibited by the antioxidant rutin.
Animals
;
Caspase 3/metabolism
;
Cell Movement/*drug effects
;
Cell Proliferation/*drug effects
;
Flavonoids/*pharmacology
;
Glucose/*metabolism/pharmacology
;
JNK Mitogen-Activated Protein Kinases
;
MAP Kinase Kinase 1
;
Male
;
Mitogen-Activated Protein Kinase 3
;
Muscle, Smooth, Vascular/cytology/*drug effects/enzymology
;
Myocytes, Smooth Muscle/metabolism
;
NF-kappa B/metabolism
;
Phosphatidylinositol 3-Kinases
;
Protein Kinase Inhibitors/*pharmacology
;
Rats
;
Rats, Inbred OLETF
;
Rats, Long-Evans
;
Reactive Oxygen Species/metabolism
;
Rutin/*pharmacology
;
p38 Mitogen-Activated Protein Kinases/metabolism
8.Liraglutide promotes proliferation and migration of cardiac microvascular endothelial cells through PI3K/Akt and MAPK/ERK signaling pathways.
Ying ZHANG ; Shun-Ying HU ; Tong YIN ; Feng TIAN ; Shan WANG ; Yingqian ZHANG ; YunDai CHEN
Journal of Southern Medical University 2015;35(9):1221-1226
OBJECTIVETo investigate the effect of liraglutide, an analogue of glucagon-like peptide-1, on the proliferation and migration of cardiac microvascular endothelial cells (CMECs) and explore the mechanism.
METHODSIn vitro cultured CMECs of SD rats were purified by differential adhesion method and identified immunocytochemically using CD31 antibody and factor VIII. MTT assay was performed to assess the proliferation of the first-generation cells exposed to different concentrations (0-1000 nm/L) of liraglutide. Western blotting was used to detect the activation of PI3K/Akt and MAPK/ERK signaling pathways. BrdU fluorescent labeling and scratch assay were performed to observe the proliferation and migration of CMECs following liraglutide treatment, and PI3K/Akt and MAPK/ERK pathway inhibitors LY294002 and PD98059, respectively, were used to further confirm the role of these signaling pathways in regulating the proliferation and migration of CMECs.
RESULTSImmunocytochemical staining demonstrated a proportion of double positive cells exceeding 95%. The cells exhibited a logarithmic growth 48 h after plating. Liraglutide exposure concentration-dependently promoted the proliferation of CMECs with the optimal concentration of 100 nmol/L (P<0.05). Liraglutide exposure of the cells for 24 h significantly increased the levels of intracellular phosphorylated Akt and ERK (P<0.05), but pretreatment of the cells with Akt and ERK signaling pathway inhibitors 1 h before liraglutide obviously reversed such effect (P<0.05). BrdU and scratch assay showed that 100 nmol/L liraglutide significantly promoted the proliferation and migration of CMECs (P<0.05), but such effects were obviously suppressed by Akt and ERK inhibitors (P<0.05).
CONCLUSIONLiraglutide promotes the proliferation and migration of CMECs in vitro via PI3K/Akt and MAPK/ERK signaling pathways.
Animals ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chromones ; Endothelial Cells ; cytology ; drug effects ; Flavonoids ; Glucagon-Like Peptide 1 ; analogs & derivatives ; pharmacology ; Liraglutide ; MAP Kinase Signaling System ; Morpholines ; Myocardium ; cytology ; Phosphatidylinositol 3-Kinases ; metabolism ; Phosphorylation ; Rats ; Rats, Sprague-Dawley
9.Bilirubin Activates Transcription of HIF-1alpha in Human Proximal Tubular Cells Cultured in the Physiologic Oxygen Content.
Sung Gyun KIM ; Shin Young AHN ; Eun Seong LEE ; Sejoong KIM ; Ki Young NA ; Dong Wan CHAE ; Ho Jun CHIN
Journal of Korean Medical Science 2014;29(Suppl 2):S146-S154
The expression of hypoxia-inducible factor (HIF) is influenced by reactive oxygen species (ROS). Effect of bilirubin on HIF-1 expression in proximal tubular cells was investigated under physiological oxygen concentration, which is relative hypoxic condition mimicking oxygen content in the medulla of renal tissue. The human kidney (HK2) cells were cultured in 5% oxygen with or without bilirubin. HIF-1alpha protein expression was increased by bilirubin treatment at 0.01-0.2 mg/dL concentration. The messenger RNA expression of HIF-1alpha was increased by 1.69+/-0.05 folds in the cells cultured with 0.1 mg/dL bilirubin, compared to the control cells. The inhibitors of PI3K/mTOR, PI3K/AKT, and ERK 1/2 pathways did not attenuate increased HIF-1alpha expression by bilirubin. HIF-1alpha expression decreased by 10 microM exogenous hydrogen peroxide (H2O2); scavenger of ROS with or without bilirubin in the HK2 cells increased HIF-1alpha concentration more than that in the cells without bilirubin. Exogenous H2O2 decreased the phosphorylation of P70S6 kinase, which was completely reversed by bilirubin treatment. Knockdown of NOX4 gene by small interfering RNA (siRNA) increased HIF-1alpha mRNA expression. In coonclusion, bilirubin enhances HIF-1alpha transcription as well as the up-regulation of HIF-1alpha protein translation through the attenuation of ROS and subunits of NADPH oxidase.
Bilirubin/*pharmacology
;
Cell Line
;
Epithelial Cells/cytology/metabolism
;
Humans
;
Hydrogen Peroxide/toxicity
;
Hypoxia-Inducible Factor 1, alpha Subunit/genetics/*metabolism
;
Kidney Tubules, Proximal/cytology
;
Mitogen-Activated Protein Kinase 1/metabolism
;
Mitogen-Activated Protein Kinase 3/metabolism
;
NADPH Oxidase/antagonists & inhibitors/genetics/metabolism
;
Oxygen/*pharmacology
;
Phosphatidylinositol 3-Kinases/metabolism
;
Phosphorylation/drug effects
;
Proto-Oncogene Proteins c-akt/metabolism
;
RNA Interference
;
Ribosomal Protein S6 Kinases, 70-kDa/metabolism
;
Signal Transduction/drug effects
;
TOR Serine-Threonine Kinases/metabolism
;
Transcriptional Activation/*drug effects
;
Up-Regulation/drug effects
10.Salidroside via ERK1/2 and PI3K/AKT/mTOR signal pathway induces mouse bone marrow mesenchymal stem cells differentiation into neural cells.
Ya-Nan CHEN ; Hui LIU ; Hong-Bin ZHAO ; Yang LIU ; Jie BAI ; Xiao-Juan ZHU ; Yu WANG
Acta Pharmaceutica Sinica 2013;48(8):1247-1252
To investigate the role of the extracellular signal-regulated kinase (ERK1/2) and PI3K/AKT/ mTOR signal pathway inducing bone marrow mesenchymal stem cells (BMSCs) differentiation into neural cells, mouse bone marrow-derived mesenchymal stem cell lines D1 cells were used as research object. And they were divided into control groups and salidroside (SD) groups. Different concentrations (5, 25, 50, 100 and 200 microg x mL(-1) of SD were used and SD (100 microg x mL(-1)) was used to induce at different time (0.5, 1, 3, 6, 9, 12, 24, 48 and 72 h). The immunofluorescence staining chemical technology, real-time PCR and Western blotting were used to detect the positive rates of NSE, MAP2, beta-Tubulin III, NES, GFAP and the expression levels of beta-Tubulin III, NSE, ERK1/2, AKT. The expression of ERK1/2 and NSE was detected when the ERK1/2 and PI3K/AKT/ mTOR signal pathway was blocked by PD98059 and LY294002. It indicated that the positive rates of NSE, MAP2, beta-Tubulin III, NES and GFAP were gradually enhanced with time increased. The expression level of NSE and beta-Tubulin III protein were significantly higher than those in control groups (P < 0.01). The expression of ERK1/2, AKT mRNA and protein were higher with concentration and time increased. When the ERK1/2 and PI3K/AKT/mTOR signal pathway were blocked, the expression levels of NSE, NES and beta-Tubulin III mRNA and NSE protein were inhibited significantly. It points out that SD can stimulate the ERK1/2 and PI3K/AKT/mTOR signal pathway to promote BMSCs differentiation into neural cells.
Animals
;
Bone Marrow Cells
;
cytology
;
Cell Differentiation
;
drug effects
;
Cells, Cultured
;
Chromones
;
pharmacology
;
Enzyme Inhibitors
;
pharmacology
;
Flavonoids
;
pharmacology
;
Glial Fibrillary Acidic Protein
;
metabolism
;
Glucosides
;
antagonists & inhibitors
;
isolation & purification
;
pharmacology
;
MAP Kinase Signaling System
;
drug effects
;
Mesenchymal Stromal Cells
;
cytology
;
Mice
;
Microtubule-Associated Proteins
;
metabolism
;
Mitogen-Activated Protein Kinase 1
;
genetics
;
metabolism
;
Mitogen-Activated Protein Kinase 3
;
genetics
;
metabolism
;
Morpholines
;
pharmacology
;
Nestin
;
metabolism
;
Neurons
;
cytology
;
metabolism
;
Phenols
;
antagonists & inhibitors
;
isolation & purification
;
pharmacology
;
Phosphatidylinositol 3-Kinases
;
metabolism
;
Phosphopyruvate Hydratase
;
genetics
;
metabolism
;
Plants, Medicinal
;
chemistry
;
Protein Kinase Inhibitors
;
pharmacology
;
Proto-Oncogene Proteins c-akt
;
genetics
;
metabolism
;
RNA, Messenger
;
metabolism
;
Rhodiola
;
chemistry
;
Signal Transduction
;
drug effects
;
TOR Serine-Threonine Kinases
;
metabolism
;
Tubulin
;
metabolism

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