OBJECTIVE: To investigate the regulatory effects of miR-26a-5p on the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) by regulating cAMP response element binding protein 1 (CREB1). METHODS: The adipose tissues of four 3-4 weeks old female C57BL/6 mice were collected and the cells were isolated and cultured by digestion separation method. After morphological observation and identification by flow cytometry, the 3rd-generation cells were subjected to osteogenic differentiation induction. At 0, 3, 7, and 14 days after osteogenic differentiation induction, the calcium deposition was observed by alizarin red staining, ALP activity was detected, miR- 26a-5p and CREB1 mRNA expressions were examined by real-time fluorescence quantitative PCR, and CREB1 protein and its phosphorylation (phospho-CREB1, p-CREB1) level were measured by Western blot. After the binding sites between miR-26a-5p and CREB1 was predicted by the starBase database, HEK-293T cells were used to conduct a dual-luciferase reporter gene experiment to verify the targeting relationship (represented as luciferase activity after 48 hours of culture). Finally, miR-26a-p inhibitor (experimental group) and the corresponding negative control (control group) were transfected into ADSCs. Alizarin red staining, ALP activity, real-time fluorescent quantitative PCR (miR-26a-5p) and Western blot [CREB1, p-CREB1, Runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN)] were performed at 7 and 14 days after osteogenic induction culture. RESULTS: The cultured cells were identified as ADSCs. With the prolongation of osteogenic induction culture, the number of calcified nodules and ALP activity significantly increased ( P<0.05). The relative expression of miR-26a-5p in the cells gradually decreased, while the relative expressions of CREB1 mRNA and protein, as well as the relative expression of p-CREB1 protein were increased. The differences were significant between 7, 14 days and 0 day ( P<0.05). There was no significant difference in p-CREB1/CREB1 between different time points ( P>0.05). The starBase database predicted that miR-26a-5p and CREB1 had targeted binding sequences, and the dual-luciferase reporter gene experiment revealed that overexpression of miR-26a-5p significantly suppressed CREB1 wild-type luciferase activity ( P<0.05). After 7 and 14 days of osteogenic induction, compared with the control group, the number of calcified nodules, ALP activity, and relative expressions of CREB1, p-CREB1, OCN, and RUNX2 proteins in the experimental group significantly increased ( P<0.05). There was no significant difference in p-CREB1/CREB1 between the two groups ( P>0.05). CONCLUSION Knocking down miR-26a-5p promoted the osteogenic differentiation of ADSCs by up-regulating CREB1 and its phosphorylation.
Animals ; Female ; Mice ; Cell Differentiation ; Cells, Cultured ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Cyclic AMP Response Element-Binding Protein/metabolism* ; Mesenchymal Stem Cells ; Mice, Inbred C57BL ; MicroRNAs/metabolism* ; Osteocalcin/metabolism* ; Osteogenesis/genetics* ; RNA, Messenger/genetics*

This study aims to investigate the effects of baicalein(BAI) on lipopolysaccharide(LPS)-induced human microglial clone 3(HMC3) cells, with a focus on suppressing inflammatory responses and elucidating the potential mechanism underlying the therapeutic effects of BAI on ischemic stroke via modulating the cAMP-PKA-NF-κB/CREB pathway. The findings have significant implications for the application of traditional Chinese medicine in treating cerebral ischemic diseases. First, the safe dosage of BAI was screened, and then an inflammation model was established with HMC3 cells by induction with LPS for 24 h. The cells were assigned into a control group, a model group, and high-, medium-, and low-dose(5, 2.5, and 1.25 μmol·L~(-1), respectively) BAI groups. The levels of superoxide dismutase(SOD) and malondialdehyde(MDA) in cell extracts, as well as the levels of interleukin-1β(IL-1β), IL-6, tumor necrosis factor-α(TNF-α), and cyclic adenosine monophosphate(cAMP) in the cell supernatant, were measured. Western blot was performed to determine the expression of protein kinase A(PKA), phosphorylated cAMP-response element binding protein(p-CREB), and nuclear factor-kappa B p65(NF-κB p65). Hoechst 33342/PI staining was employed to assess cell apoptosis. High and low doses of BAI were used for treatment in the research on the mechanism. The results revealed that BAI at the concentrations of 10 μmol·L~(-1) and below had no impact on normally cultured HMC3 cells. LPS induction at 200 ng·mL~(-1) for 24 h reduced the SOD activity and increased the MDA content in HMC3 cells. However, 5, 2.5, and 1.25 μmol·L~(-1) BAI significantly increased the SOD activity and 5 μmol·L~(-1) BAI significantly decreased the MDA content. In addition, BAI ameliorated the M1 polarization of HMC3 cells induced by LPS, as indicated by cellular morphology. The results of ELISA demonstrated that BAI significantly lowered the levels of TNF-α, IL-1β, IL-6, and cAMP in the cell supernatant. Western blot revealed that BAI up-regulated the protein levels of PKA and p-CREB while down-regulating the expression of NF-κB p65. Hoechst 33342/PI staining results indicated that BAI mitigated the apoptosis of HMC3 cells. Overall, the results indicated that BAI had protective effects on the HMC3 cells induced by LPS, and could inhi-bit inflammatory response and improve cell apoptosis, which might be related to the regulation of the cAMP-PKA-NF-κB/CREB pathway.
Humans ; NF-kappa B/metabolism* ; Microglia ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6/metabolism* ; Lipopolysaccharides/pharmacology* ; Cyclic AMP-Dependent Protein Kinases/metabolism* ; Superoxide Dismutase/metabolism*

OBJECTIVE: To observe the regulative effect of Tongdu Tiaoshen acupuncture on the depression-like behavior and cAMP-response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF)/tyrosine protein kinase B (TrkB) signaling pathway of hippocampus in rats with post-stroke depression (PSD), and to explore its possible mechanism on improving PSD. METHODS: A total of 36 SPF SD rats were randomized into a sham operation group, a model group and a Tongdu Tiaoshen group, 12 rats in each group. The compound method of Zea Longa suture-occlusion and chronic unpredictable mild stress (CUMS) was used to establish the PSD model in rats of the model group and the Tongdu Tiaoshen group. On the 4th day after modeling, acupuncture was applied at "Dazhui" (GV 14), "Shuigou" (GV 26), "Baihui" (GV 20) and "Shenting" (GV 24) in the Tongdu Tiaoshen group, 40 min every time, once a day, 6 times a week for 4 weeks consecutively. On the 2nd day after PSD modeling and after 4-week intervention, Zea Longa neurobehavioral score was evaluated, sucrose water consumption test and open-field test were performed; biochemical method was used to detect the SOD, CAT activity and MDA level in hippocampal CA1 area; ELISA method was used to detect the serum level of BDNF; real-time PCR was used to detect the mRNA expression of BDNF, TrkB and CREB in hippocampal CA1 area; Western blot was used to detect the protein expression of BDNF, TrkB, CREB and p-CREB in hippocampal CA1 area. RESULTS: Compared with the sham operation group, Zea Longa neurobehavioral scores were increased (P<0.05), percentage of sucrose water consumption, horizontal motion and vertical motion scores of open-field test were decreased after modeling and intervention in the model group and after modeling in the Tongdu Tiaoshen group (P<0.05). Compared with the model group, Zea Longa neurobehavioral score was decreased (P<0.05), percentage of sucrose water consumption, horizontal motion and vertical motion scores of open-field test were increased after intervention in the Tongdu Tiaoshen group (P<0.05). Compared with the sham operation group, the SOD and CAT activity in hippocampal CA1 area and serum level of BDNF were decreased (P<0.05), MDA level in hippocampal CA1 area was increased in the model group (P<0.05); compared with the model group, the SOD and CAT activity in hippocampal CA1 area and serum level of BDNF were increased (P<0.05), MDA level was decreased in the Tongdu Tiaoshen group (P<0.05). Compared with the sham operation group, the mRNA expression of BDNF, TrkB and CREB as well as the protein expression of BDNF, TrkB, CREB and p-CREB were decreased in hippocampal CA1 area in the model group (P<0.05); compared with the model group, the mRNA expression of BDNF, TrkB and CREB, the protein expression of BDNF, TrkB and p-CREB as well as the ratio of p-CREB/CREB were increased in the Tongdu Tiaoshen group (P<0.05). CONCLUSION Tongdu Tiaoshen acupuncture can improve the depression-like behavior in PSD rats, the mechanism may be related to the inhibition of oxidative stress in hippocampal tissues and the enhanced activity of CREB/BDNF/TrkB signaling pathway.
Acupuncture Therapy ; Animals ; Brain-Derived Neurotrophic Factor/metabolism* ; Cyclic AMP Response Element-Binding Protein/metabolism* ; Depression/therapy* ; Hippocampus/metabolism* ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Stroke/complications* ; Sucrose ; Superoxide Dismutase

OBJECTIVE: To investigate the effect of miR-203/CREB1 signaling regulation mediated by DNA methylation on the proliferation, invasion and apoptosis of multiple myeloma (MM) cells. METHODS: The methylation level of miR-203 in the RPMI 8226 cells was detected by bisulfite sequcucing polymerase chain reaction (BSP). The mRNA expression of miR-203 was measured by quantitative real-time polymerase chain reaction. RPMI 8226 cells were treated with DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine (5-Aza-CdR). The miR-203 mimic in MM cell line RPMI 8226 was transfected to establish overexpressed miR-203 cell. The proliferation, invasion ability and apoptosis of RPMI 8226 cell was detected by CCK-8 assay, Transwell, and flow cytometry, respectively. The targeting relationship between miR-203 and CREB1 was verified by double luciferase report assay. Western blot was used to detect the expression of CREB1 protein. RESULTS: Hypermethylation of miR-203 promoter region and low expression level of miR-203 mRNA were detected in the RPMI 8226 cells, which showed that demethylation could induce the expression of miR-203. The proliferation and invasion ability of RPMI 8226 cells after treated by 5-Aza-CdR were inhibited, and showed statistical significance as compared with blank control group (both P<0.05)，while the apoptosis rate was promoted (P<0.05). The proliferation, invasion ability and apoptosis of overexpressed miR-203 were the same as the demethylation group. Double luciferase report assay confirmed that CREB1 was the direct target of miR-203. The protein level of CREB1 was inhibited by demethylation and showed statistical significance as compared with control group (P<0.05). CONCLUSION MiR-203 targeting CREB1 mediated by DNA methylation leads to maintain the malignant biological behaviors of MM cells.
Apoptosis ; Azacitidine/pharmacology* ; Cell Line, Tumor ; Cell Proliferation ; Cyclic AMP Response Element-Binding Protein/pharmacology* ; DNA Methylation ; Gene Expression Regulation, Neoplastic ; Humans ; MicroRNAs/metabolism* ; Multiple Myeloma/genetics* ; RNA, Messenger/metabolism*

Animals ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; genetics ; metabolism ; Cyclic AMP Response Element-Binding Protein ; genetics ; metabolism ; Male ; MicroRNAs ; radiation effects ; Microwaves ; adverse effects ; Neuronal Plasticity ; radiation effects ; Random Allocation ; Rats ; Rats, Wistar ; Receptors, N-Methyl-D-Aspartate ; genetics ; metabolism

OBJECTIVE: To observe the direct intervention effects of electroacupuncture (EA) and non-steroid anti-inflammatory drugs (NSAIDs) on pain memory, and to explore their effects on cAMP/PKA/cAMP pathway in anterior cingulate gyrus (ACC). METHODS: Fifty clean healthy male SD rats were randomly divided into a control group, a model group, an indomethacin group, an EA group and a sham EA group, 10 rats in each group. Except the control group, the pain memory model was established in the remaining four groups by twice injection of carrageenan at foot; 0.1 mL of 2%λ-carrageenan was subcutaneously injected at the left foot of rats; 14 days later, when the pain threshold of rats of each group returned to the basic level, the second injection was performed with the same procedure. The rats in the EA group were treated with EA at bilateral "Zusanli" (ST 36) for 30 min; the rats in the indomethacin group was treated with indomethacin intragastric administration with the dose of 3 mg/kg; the rats in the sham EA group was treated with EA without electricity at the point 0.3 mm forward "Zusanli" (ST 36) with the depth of 2 mm for 30 min; the rats in the control group was not given any invention. All the above interventions were performed 5 h, 1 d, 2 d and 3 d after the second injection of 2% λ-carrageenan. The left-side paw withdrawal thresholds (PWT) were observed before the first injection, 4 h, 3 d, 5 d after the first injection, before the second injection and 4 h, 1 d, 2 d, 3 d after the second injection. Three days after the second injection, the number of positive cells of cAMP, p-PKA, p-CREB and the number of positive cells of protein co-expression in the right ACC brain area were detected by immunofluorescence, and the relative protein expression of p-PKA and p-CREB were detected by Western blot. RESULTS: Compared with the control group, the PWTs in the model group decreased significantly 4 h, 3 d and 5 d after the first injection and 1 d, 2 d and 3 d after the second injection (<0.05); compared with the control group, the positive expression of cAMP, p-PKA and p-CREB in the right ACC brain area in the model group increased significantly (<0.05), and the number of positive cells of the co-expression of cAMP/p-PKA and p-PKA/p-CREB also increased significantly (<0.05). Compared with the model group, indomethacin group and sham EA group, the PWTs in the EA group were increased significantly 1 d, 2 d and 3 d after the second injection (<0.05); compared with the model group, indomethacin group and sham EA group, the positive expression of p-PKA and p-CREB in the right ACC brain area in the EA group decreased significantly (<0.05), and the number of positive cells of co-expression of cAMP/p-PKA and p-PKA/p-CREB was decreased significantly (<0.05). Compared with the model group and sham EA group, the positive expression of cAMP in the right ACC brain area was decreased in the EA group (<0.05). CONCLUSION EA have a direct intervention effect on pain memory, which have significant advantage over NSAIDs in the treatment of chronic pain. The advantage effect of EA on pain memory may be related to the inhibition of cAMP/PKA/CREB pathway in ACC area.
Animals ; Anti-Inflammatory Agents, Non-Steroidal ; therapeutic use ; Cyclic AMP ; metabolism ; Cyclic AMP Response Element-Binding Protein ; metabolism ; Cyclic AMP-Dependent Protein Kinases ; metabolism ; Electroacupuncture ; Gyrus Cinguli ; metabolism ; Male ; Pain Threshold ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Signal Transduction

Taurochenodeoxycholic acid (TCDCA) is one of the main effective components of bile acid, playing critical roles in apoptosis and immune responses through the TGR5 receptor. In this study, we reveal the interaction between TCDCA and TGR5 receptor in TGR5-knockdown H1299 cells and the regulation of inflammation via the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA)-cAMP response element binding (CREB) signal pathway in NR8383 macrophages. In TGR5-knockdown H1299 cells, TCDCA significantly activated cAMP level via TGR5 receptor, indicating TCDCA can bind to TGR5; in NR8383 macrophages TCDCA increased cAMP content compared to treatment with the adenylate cyclase (AC) inhibitor SQ22536. Moreover, activated cAMP can significantly enhance gene expression and protein levels of its downstream proteins PKA and CREB compared with groups of inhibitors. Additionally, TCDCA decreased tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-8 and IL-12 through nuclear factor kappa light chain enhancer of activated B cells (NF-κB) activity. PKA and CREB are primary regulators of anti-inflammatory and immune response. Our results thus demonstrate TCDCA plays an essential anti-inflammatory role via the signaling pathway of cAMP-PKA-CREB induced by TGR5 receptor.
Animals ; Cell Line ; Cyclic AMP/metabolism* ; Cyclic AMP Response Element-Binding Protein/metabolism* ; Cyclic AMP-Dependent Protein Kinases/metabolism* ; Cytokines/metabolism* ; Humans ; Inflammation ; Macrophages ; Rats ; Receptors, G-Protein-Coupled/metabolism* ; Signal Transduction/drug effects* ; Taurochenodeoxycholic Acid/pharmacology*

OBJECTIVE: To explore the effect of electrical stimulation at auricular points (EAS) combined with sound masking on the expression of cAMP-response element binding protein (CREB), brain-derived neurotrophic factor (BDNF) and tyrosine receptor kinase B (TrkB) in the auditory cortex of tinnitus rats. METHODS: A total of 27 adult male SD rats were randomly divided into a control group, a model group and an EAS group. The rats in the model group and the EAS group were intervened with intraperitoneal injection of sodium salicylate to induce tinnitus model, while the rats in the control group were intervened with injection of 0.9% NaCl solution. After the model was successfully established, the rats in the EAS group were treated with electrical stimulation at "Shenmen" (TF) and "Yidan" (CO), combined with sound masking; the treatment was given once a day for 15 days. The gap prepulse inhibition of acoustic startle (GPIAS) and prepulse inhibition (PPI) testing were performed using the acoustic startle reflex starter package for rats. The expression of BDNF, TrkB, CREB and p-CREB in the auditory cortex of each group were measured with Western Blot analysis. RESULTS: ① Compared with the control group, the GPIAS values in 12 kHz, 16 kHz, 20 kHz and 28 kHz were significantly decreased in the model group (all <0.05); compared with the model group, GPIAS values in 12 kHz, 16 kHz, 20 kHz and 28 kHz were significantly increased in the EAS group (all <0.05). ② Compared with the control group, the expression of BDNF and p-CREB in the model group was significantly increased (<0.01), and the expression of TrkB in the model group was significantly increased (<0.05); the differences of expression of BDNF, TrkB, CREB and p-CREB between the model group and the EAS group had no statistics significance (all >0.05). CONCLUSION EAS could improve the GPIAS values of high-frequency background sound in tinnitus rats, which may be related with the upregulation of the BDNF/TrkB/CREB signaling pathway in the auditory cortex, leading to the reversion of the maladaptive plasticity.
Acupuncture Points ; Animals ; Auditory Cortex ; Brain-Derived Neurotrophic Factor ; metabolism ; Cyclic AMP Response Element-Binding Protein ; metabolism ; Electric Stimulation ; Male ; Rats ; Rats, Sprague-Dawley ; Receptor, trkB ; metabolism ; Tinnitus ; metabolism ; therapy

OBJECTIVE: To investigate the effects of Acorus tatarinowii Schott and its active component 5- hydroxymethyl furfural (HMF) on learning and memory and ERK/CREB signal in hippocampus of rats with exercise-induced fatigue. METHODS: SD rats were randomly divided into normal group (A), exercise group (B), exercise + HMF low, middle and high dose treatment group (C, D, E), exercise + acorus tatarinowii Schott low, middle and high dose treatment group (F, G, H), with ten rats in each group. The rats in group C, D and E were treated with HMF at the doses of 0.10, 1.00 and 3.00 mg. kg by ig. The rats in group F, G and H were treated with the extracts of Acorus tatarinowii Schott at the doses of 0.12, 1.20 and 4.80 g. kg by ig. Learning and memory of rats were tested by the method of water maze experiment, and the expression levels of p-ERK1/2 and p-CREB protein in hippocampus of rats were tested by the method of Western blot in the end of the experiment. RESULTS: The escape latencies of E and H groups were lower than those of groups B, C, D, F and G; and the numbers of plateau crossing were more than those of groups B, C, D, F and G and the expression levels of p-ERK1/2, p-CREB protein were higher than those of groups B, C, D, F and G , respectively(P ＜ 0.01). There was no significant difference in the above indexes among groups A, E and H(P＞0.05) except that the expression levels of p-ERK2 protein in group E were lower than those in group A and H (P＜0.05). CONCLUSION Acorus tatarinowii and its active component- HMF can improve the learning and memory of rats with exercise-induced fatigue, and the mechanism is related to the up-regulation of ERK / CREB signal in hippocampus of rats with exercise-induced fatigue.
Acorus ; chemistry ; Animals ; Cyclic AMP Response Element-Binding Protein ; metabolism ; Fatigue ; drug therapy ; Furaldehyde ; analogs & derivatives ; pharmacology ; Hippocampus ; metabolism ; MAP Kinase Signaling System ; Maze Learning ; drug effects ; Memory ; drug effects ; Physical Conditioning, Animal ; Phytochemicals ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To study the effect of exendin-4(Ex-4) on the differentiation of neural stem cells(NSCs) in adult mouse subventricular zone(SVZ)and its mechanism . METHODS: NSCs in the SVZ were derived from 5-week C57BL/6J mice and the expression of nestin was detected by immunofluorescence. The cell morphology was observed after the cells treatmed with 100 nmol/L Ex-4 for 14 days.The expressions of nestin and glucagon-like peptide-1 receptor (GLP-1R) were detected by immunofluorescence. GLP-1R was knocked down by using shRNA and the study was divided into four groups: control group, Ex-4 group, GLP-1R knockdown group, GLP-1R knockdown + Ex-4 group. After treatment with 100 nmol/L Ex-4 for 14 d, β-tublin III and glial fibrillary acidic protein (GFAP) were labeled by immunofluorescence and then the proportion of β-tublin III positive cells were counted. Western blot was used to detect the activation of cAMP-response element binding protein (CREB) in NSCs. In order to further study the effects of Ex-4 on mitogen-activated protein kinase(MAPK) and phosphatidylinositol 3-hydroxy kinase (PI3K) pathways, the cells were pretreated with MAPK inhibitor U0126 at a concentration of 0.07 μmol/L for 30 min or PI3K inhibitor LY294002 at 50 μmol for 2 h, respectively. The study was divided into six groups: control group, Ex-4 group, U0126 group, U0126 + Ex-4 group, LY294002 group, LY294002 + Ex-4 group. The activation of CREB in each group was detected by Western blot. The experiment was repeated three times independently. RESULTS: NSCs were successfully extracted from SVZ of C57BL/6J mice. Immunofluorescence showed that nestin and GLP-1R were positive in NSCs. Compared with the control group, the proportion of neurons differentiated from Ex-4 group was higher. The percentage of neurons in GLP-1R knockdown + Ex-4 group was basically the same as that in control group (P＜0.01). The positive cells of beta-tublin III showed positive activation of GLP-1R and CREB. Western blot showed that CREB was significantly activated in the Ex-4 group, and knockdown of GLP-1R abolished its activation (P＜0.01). U0126 did not affect Ex-4-mediated CERB activation, and LY294002 significantly reduced Ex-4-mediated CREB activation (P＜0.01). CONCLUSION Ex-4 promotes the differentiation of NSCs into neurons in SVZ of adult mice through GLP-1R receptor, which may be achieved through PI3K/CREB pathway.
Animals ; Cell Differentiation ; Cells, Cultured ; Cyclic AMP Response Element-Binding Protein ; metabolism ; Exenatide ; pharmacology ; Gene Knockdown Techniques ; Glucagon-Like Peptide-1 Receptor ; genetics ; metabolism ; Lateral Ventricles ; cytology ; Mice ; Mice, Inbred C57BL ; Neural Stem Cells ; cytology ; Phosphatidylinositol 3-Kinases