Expression Of Extracellular Regulated Protein Kinases Research Articles

Modulation of glycolipid metabolism in T2DM rats by Rubus irritans Focke extract: Insights from metabolic profiling and ERK/IRS-1 signaling pathway

Ethnopharmacological relevanceThe extracellular regulated protein kinase (ERK) plays a crucial role in the mitogen-activated protein kinase (MAPK) family, influencing apoptosis, proliferation, and differentiation. It connection to the insulin (INS) signaling cascade and the development of type 2 diabetes mellitus (T2DM) has been established. Rubus irritans Focke, an indispensable herb in Chinese Tibetan medicine for diabetes mellitus treatment, lacks a comprehensive understanding of its effects and pharmacological mechanisms in T2DM. Aim of the studyThis study aimed to elucidate the effects of Rubus irritans Focke extract (Rife) on a T2DM rat model, exploring its impact on glycemic and lipid metabolism, histopathological changes, and its potential targeting of the extracellular regulated protein kinase/insulin receptor substrate-1 (ERK/IRS-1) signaling pathway. Materials and methodsA T2DM rat model was induced by streptozotocin (STZ) injection (40 mg/kg) in high-fat diet-fed (HFD) male Wistar rats. Rife and metformin (Met) were administered for 4 weeks, and glycemic, lipid metabolism indices, and histopathological changes were assessed. Protein expression of ERK, IRS-1 in rat liver tissues was examined to evaluate the impact on the ERK/IRS-1 pathway. ResultsRife reducing hepatic ERK and IRS-1 protein expression in T2DM rats. Untargeted metabolomics identified 13 potential biomarkers and 4 differential metabolic pathways related to glycolipid metabolism disorders. ConclusionsRife demonstrated improved glycolipid metabolism in T2DM rats by inhibiting the ERK/IRS-1 related signaling pathway and influencing multiple metabolic pathways. This study provides valuable insights into the potential therapeutic mechanisms of Rife in the context of T2DM.

Effect of Echinacea purpurea (L.) Moench and its extracts on the immunization outcome of avian influenza vaccine in broilers

Ethnopharmacological relevanceEchinacea purpurea (L.) Moench (EP) is a perennial herbaceous flowering plant with immunomodulatory effects. However, the immunomodulatory effects of EP on broilers after vaccination are still unclear. Aim of the studyThe aim is to study the effect of EP and Echinacea purpurea (L.) Moench extracts(EE) on avian influenza virus (AIV) immunity, and further explore the potential mechanism of immune regulation. Materials and methodsBroilers were fed with feed additives containing 2% EP or 0.5% EE, and vaccinated against avian influenza. The samples were collected on the 7th, 21st, and 35th day after vaccination, and the feed conversion ratio (FCR) was calculated. Blood antibody titer, jejunal sIgA content, tight junction protein, gene and protein expression of TLR4-MAPK signaling pathway were also detected. ResultsThe results showed that vaccination could cause immune stress, weight loss, increase sIgA content, and up-regulate the expression of tight junction proteins, including zonula occludens-1 (ZO-1), Occludin, and Claudin-1, as well as the genes of Toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), receptor-associated factor 6 (TRAF6), activator protein 1 (AP-1) protein gene expression on TLR4-mitogen-activated protein kinase (MAPK) signaling pathway, and the protein expression of MyD88, extracellular regulated protein kinases (ERK), and c-Jun N-terminal kinase (JNK). EP and EE could increase the body weight of broilers, further improve antibody titers, decrease FCR, increase sIgA levels, up-regulate the expression of tight junction proteins, including ZO-1, Occludin, and Claudin-1, as well as the genes of TLR4, MyD88, TRAF6, and AP-1 and the protein expression of MyD88, ERK, and JNK in the TLR4-MAPK signaling pathway. ConclusionIn conclusion, EP and EE can increase the broiler's production performance and improve vaccine immune effect through the TLR4-MAPK signaling pathway.

Role of EtMIC4 EGF-like in regulating the apoptosis of Eimeria tenella host cells via the EGFR pathway

This study aimed to explore the role and key point of EtMIC4 EGF-like recombinant protein in regulating the apoptosis of Eimeria tenella host cells via the epidermal growth factor receptor (EGFR) pathway. The cells were treated with EtMIC4 EGF-like protein, EGFR-specific siRNA, or both. Infection and apoptosis rates as well as dynamic changes in the key genes and proteins of the EGFR signaling pathway in the host cells were determined. Results showed that the E. tenella and EtMIC4 EGF-like group had the highest infection rate (P < 0.01). In cells treated with EtMIC4 EGF-like for 4 to 24 h, the apoptosis rate was significantly decreased (P < 0.01) and the relative mRNA expression and protein phosphorylation levels of EGFR, protein kinase B (AKT), and extracellular regulated protein kinases (ERK) were significantly increased (P < 0.01). In E. tenella sporozoites infected for 4 to 96 h, the rate of host cell apoptosis induced by E. tenella infection was significantly (P < 0.01) reduced by EtMIC4 EGF-like. The relative mRNA expression and protein phosphorylation levels of EGFR, AKT, and ERK in the host cells of E. tenella + EtMIC4 EGF-like group were significantly increased (P < 0.01). These results indicated that E. tenella could activate the EGFR pathway through EtMIC4 EGF-like and regulate the expression of key genes in the AKT and ERK signaling pathways, thereby inhibiting cell apoptosis.

Baicalin ameliorates chronic unpredictable mild stress-induced depression through the BDNF/ERK/CREB signaling pathway

Brain-derived neurotrophic factor (BDNF) can activate the extracellular regulated protein kinase (ERK)/cAMP response element binding protein (CREB) cascade revealing an important role in antidepressant effects. Here, we studied the neuroprotective effect of baicalin (BA) in mice with chronic unpredictable mild stress (CUMS)-induced via a BDNF/ERK/CREB signaling pathway. Depression was induced via six weeks of CUMS in male ICR mice, and drug therapy was given simultaneously for the last three weeks. Cognitive dysfunctions were then evaluated via sucrose preference test (SPT), open field test (OFT), Morris water maze test (MWM), tail suspension test (TST), and novelty suppressed feeding test (NSF). Western blot and real-time PCR were then used to detect the relative expression of ERK, CREB, p-ERK, and p-CREB. Integrated optical density (IOD) tests of p-ERK and p-CREB were then evaluated via immunofluorescence. The behavior results showed that the cognitive dysfunctions increased in the CUMS group versus the control (CON) group (p < 0.01). There were decreases in fluoxetine (FLU) and BA groups (p < 0.05, p < 0.01). The protein ratios of p-ERK/ERK, p-CREB/CREB and ERK mRNA, and CREB mRNA expression decreased in the CUMS group (p < 0.01) and markedly increased in the FLU and BA groups (p < 0.05, p < 0.01). The IOD value of the p-ERK and p-CREB in the CUMS group was decreased versus the CON group (p < 0.01), and these changes were improved via BA and FLU treatment (p < 0.05, p < 0.01). This study indicated that BA can improve cognitive functions and has antidepressant effects in mice, which may be associated with activation of the BDNF/ERK/CREB signaling pathway in the hippocampus.

Proline-Serine-Threonine Phosphatase-Interacting Protein 2 Alleviates Diabetes Mellitus-Osteoarthritis in Rats through Attenuating Synovial Inflammation and Cartilage Injury.

ObjectiveTo explore the possible way of proline‐serine–threonine phosphatase‐interacting protein 2 (PSTPIP2) influencing diabetes mellitus‐osteoarthritis (DM‐OA) progression.Methods In vivo, eight‐week‐old male Sprague Dawley rats were induced with DM‐OA by intraperitoneal injection of streptozotocin with high‐fat diet feeding and intra‐articular injection of monoiodoacetate. PSTPIP2 overexpression was achieved by intra‐articular injection of lentivirus vectors. PSTPIP2 expression was verified by real‐time polymerase chain reaction and Western blotting. Histological changes were examined by hematoxylin/eosin and safranin‐O/fast‐green staining. In vitro, rat synovial fibroblasts were induced DM‐OA by stimulation of high glucose (HG) and interleukin (IL)‐1β. PSTPIP2 overexpression was achieved by lentivirus infection. U0126 was added as an ERK inhibitor. Levels of tumor necrosis factor (TNF)‐α, IL‐6, and IL‐1β were detected using enzyme‐linked immunosorbent assay. Expression of matrix metalloproteinase (MMP)‐3, MMP‐13, aggrecanase‐2 (ADAMTS‐5), intercellular cell adhesion molecule (ICAM)‐1, extracellular regulated protein kinase (ERK) and phospho‐ERK (p‐ERK) was detected by Western blotting.ResultsIn DM‐OA rats, PSTPIP2 relative messenger RNA (mRNA) level was significantly decreased compared to control rats. The protein expression was also decreased obviously. Inflammation score in synovium was dramatically increased, accompanying with increased TNF‐α, IL‐6, and IL‐1β levels. Osteoarthritis research society international (OARSI) score in cartilage was markedly increased, along with increased MMP‐3, MMP‐13, ADAMTS‐5, ICAM‐1, ERK and p‐ERK expression. In PSTPIP2‐overexpressed DM‐OA rats, PSTPIP2 mRNA level and protein expression was increased compared to DM‐OA rats received negative‐control lentivirus vectors. The inflammation score, as well as TNF‐α, IL‐6, and IL‐1β levels were dramatically decreased. Also, the OARSI score and protein expression of MMP‐3, MMP‐13, ADAMTS‐5, ICAM‐1, ERK and p‐ERK were decreased. In HG+IL‐1β‐treated rat synovial fibroblasts, PSTPIP2 protein expression was decreased compared to normal glucose (NG)‐treated cells. Levels of TNF‐α, IL‐6, and IL‐1β, as well as expression of MMP‐3, MMP‐13, ADAMTS‐5, ICAM‐1, ERK and p‐ERK were increased. After cells were infected with PSTPIP2‐overexpressed lentivirus, levels of TNF‐α, IL‐6, and IL‐1β, and expression of MMP‐3, MMP‐13, ADAMTS‐5, ICAM‐1, ERK and p‐ERK were obviously decreased compared to cells infected with NC lentivirus. In addition, ERK inhibitor U0126 treatment also decreased the TNF‐α, IL‐6, and IL‐1βlevels and MMP‐3, MMP‐13, ADAMTS‐5, ICAM‐1, ERK and p‐ERK expression in HG + IL‐1β treated rat synovial fibroblasts.ConclusionOverexpression of PSTPIP2 alleviates synovial inflammation and cartilage injury during DM‐OA progression via inhibiting ERK phosphorylation.

Hydroxysafflor yellow A alleviates cerebral ischemia reperfusion injury by suppressing apoptosis via mitochondrial permeability transition pore

BackgroundMitochondria are key cellular organelles that are essential for cell fate decisions. Hydroxysafflor yellow A (HSYA) has displayed an impressively essential role in protection of cerebral ischemia/reperfusion (I/R). However, the mitochondrial effect of HSYA on Brain Microvascular Endothelial Cells (BMECs) under I/R remains to be largely unclear. PurposeTo evaluate the protective effects of HSYA-mediated mitochondrial permeability transition pore (mPTP) on cerebral I/R injury and its mechanism. MethodsCerebral I/R injury was established by the model of Middle cerebral artery occlusion (MCAO) in rats. Furthermore, to further clarify the relevant mechanism of HSYA's effects on mPTP, inhibition of extracellular regulated protein kinases (ERK) with U0126 and transfect with Cyclophilin D (CypD) SiRNA to reversely verified whether the protective effects of HSYA were exerted by regulating the Mitogen-activated protein kinase kinase (MEK)/ERK/CypD pathway. ResultsHSYA treatment significantly increased BMECs viability, decreased the generation of ROS, opening of mPTP and translocation of cytochrome c after OGD/R. In addition to inhibited CypD, HSYA potentiated MEK and increased phosphorylation of ERK expression in BMECs, inhibited apoptosis mediated by mitochondrial. Notably, HSYA also significantly ameliorated neurological deficits and decreased the infarct volume in rats. ConclusionHSYA reduced the CytC export from mitochondrial by inhibited the open of mPTP via MEK/ERK/CypD pathway, contributing to the protection of I/R. Thus, our study not only revealed novel mechanisms of HSYA for its anti-I/R function, but also provided a template for the design of novel mPTP inhibitor for the treatment of various mPTP-related diseases.

Effect of miR-497 on myocardial cell apoptosis in rats with myocardial ischemia/reperfusion through the MAPK/ERK signaling pathway.

The aim of this study was to investigate the effect of micro ribonucleic acid (miR)-497 on myocardial cell apoptosis in rats with myocardial ischemia/reperfusion (I/R) through the mitogen-activated protein kinase (MAPK)/extracellular regulated protein kinase (ERK) signaling pathway. A rat model of myocardial I/R was established, myocardial cells were extracted, and miR-497 was inhibited by inhibitors and overexpressed using miRNA mimics. The cell apoptosis rate was detected by flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The interaction between miR-497 and ERK was determined by dual-luciferase reporter gene assay. The change in the protein level was measured via Western blotting (WB). Up-regulation of miR-497 promoted myocardial cell apoptosis, and the 3'-untranslated region (3'-UTR) of ERK was highly conserved to combine with miR-497. The luciferase reporter gene assay showed that the transfection of miR-497 could significantly inhibit the relative luciferase activity in cells. MiR-497 overexpression significantly down-regulated the ERK expression at messenger RNA (mRNA) and protein levels in cells. MiR-497 plays an important role in regulating I/R injury-induced myocardial cell apoptosis by targeting the ERK-induced apoptosis pathway.

Vitamin K3 Regulates Reactive Oxygen Species and Extracellular-Regulated Protein Kinase in Differentiated PC-12 Cells within a Safe Dose Range

Objective: Acupuncture can relieve pain by acting on the mitogen-activated protein kinase (MAPK) signal pathway, which plays a critical role in the balance between hyperalgesia and inflammation. Our previous studies have suggested that acupoint injection of Vitamin K3 (Vit K3) had an intensive analgesic effect on primary dyspareunia. However, the mechanism by which Vit K3 worked on nerve cells has not been elucidated. Methods: Cell apoptosis, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) changes of PC-12 cells with Vit K3 treatment, for which the concentration gradient was 0, 5, 10, 20, 40, and 60 μmol/L, were quantified by flow cytometry. The expression and phosphorylation of c-Jun N-terminal kinase, p38, and extracellular-regulated protein kinase (ERK), the three critical molecules of the MAPK pathway, were further assessed using Western blotting. Results: The level of ROS first decreased and then increased with Vit K3 at 20 μmol/L, but no change in neither apoptosis nor MMP was evident. In addition, only ERK level decreased at 20 μmol/L and the relative phosphorylation level increased. Changes in ROS were negatively correlated with the expression of ERK. Conclusions: The rapid analgesic effect of Vit K3 acupoint injection may be through the reduction of ROS in nerve cells with a small dose of Vit K3 or by influencing the expression of ERK but without damaging the nerve cells themselves.

ERK expression and its correlation with STAT1 in esophageal squamous cell carcinoma.

BackgroundEsophageal squamous cell carcinoma is one of leading causes of cancer-related deaths in Chaoshan region a high-risk region for esophageal cancer. Extracellular regulated protein kinases (ERK) usually play an important role in cell proliferation and differentiation. However, accumulating evidence has shown that the ERK was aberrantly expressed in cancers and correlated with STAT1 depression.ResultsThe activated ERK downregulates STAT1 expression in ESCC cell lines and U0126 increases expression of STAT1. Our immunohistochemistry result also confirms that the expression of ERK inversely correlated with that of STAT1 in ESCC tumors. In addition, a significantly higher expression of ERK/p-ERK was found in ESCC tissues in comparison with case-matched normal esophageal tissues (p < 0.05). Moreover, the immunohistochemical analysis demonstrated that ERK expression was paralleled with the differentiation and clinical stage. In 74 patients with follow-up data, those with ERKlow tumors survived significantly longer than those with ERKhigh tumors (p = 0.04); patients with ERKlow/STAT1high tumors had the longest survival (p = 0.001).Materials and MethodsTo investigate whether ERK can mediated STAT1 expression in ESCC, we used the MEK plasmid and U0126, a MEK inhibitor, to treat the cell. To further confirm our in-vitro study, we detected the ERK, p-ERK and STAT1 expression in 131 ESCC cases and 22 case-matched normal esophageal tissues adjacent to the tumors specimens.ConclusionsThese findings provide pathological evidence that ERK/p-ERK is negatively correlated with STAT1 in ESCC. Our data suggests that inhibition of ERK and/or restoration of STAT1 expression maybe useful therapeutic strategies for ESCC.

STUDY ON MOLECULAR MECHANISM OF OSTEOCLAST DIFFERENTIATION INDUCED BY STAPHYLOCOCCAL PEPTIDOGLYCAN

To investigate the molecular mechanism of osteoclast differentiation induced by Staphylococcal peptidoglycan (PGN-sa). Raw264.7 cells were stimulated with PGN-sa and with PGN-sa+SC75741[a potent inhibitor of nuclear factor κB (NF-κB) activation] in a concentration of 200 ng/mL. The protein expression of nuclear factor of activated T-cells cytoplasmic 1 (NFATc1) was tested at 0, 1, 2, and 3 days; the proteins related to osteoclast differentiation of extracellular regulated protein kinases (ERK), p38, c-Jun N-terminal kinase (JNK), NF-κB, inhibitor of NF-κB (IκB-α), Akt, and the phosphorylation forms of p38, ERK, JNK, Akt, NF-κB were measured at 0, 5, 10, 20, 40, and 60 minutes by Western blot. In addition, Raw264.7 cells were stimulated with PGN-sa in the concentrations of 100 ng/mL (group A), 200 ng/mL (group B), 400 ng/mL (group C), and with PBS (group D) for 1, 2, and 3 days; the expression levels of tumor necrosis factor α (TNF-α), interleukin 1α (IL-1α), and IL-6 were detected by ELISA. The results of Western blot showed that the expression of NFATc1 increased gradually with time, showing significant difference between different time points (P<0.05). However, after SC75741 was added, the expression of NFATc1 was inhibited at 2 and 3 days, showing significant difference when compared with no addition of SC75741 (P<0.001). After stimulation of PGN-sa, the expression of IkB-α decreased significantly at 5 and 10 minutes when compared with those at the other time points (P<0.001), and returned to normal at 20 minutes. Meanwhile, the expression of p-NF-κB increased significantly at 5 and 10 minutes when compared with those at the other time points (P<0.001), and returned to normal at 20 minutes; and the expression of p-NF-κB at 5 minutes was significantly higher than that at 10 minutes (P<0.001). After the addition of SC75741, there was no change in the expressions of IκB-α and p-NF-κB, showing no significant difference between different time points P>0.05). Moreover, the expressions of ERK, p38, JNK, NF-κB, Akt, p-p38, p-ERK, p-JNK, and p-Akt showed no significant change between different time points P>0.05). ELISA results showed that there were no expressions of TNF-α and IL-1α in groups A-D at different time points. The expression of IL-6 had an increasing trend with time prolonged in each group, showing significant differences between different time points (P<0.05). Moreover, at 1 day after culture, the expression of IL-6 showed no significant difference among groups P>0.05). At 2 and 3 days after culture, the expression of IL-6 in groups A-C showed an increasing trend and was significantly higher than that in group D, showing significant difference among groups (P<0.05). PGN-sa can promote osteoclast differentiation through NF-κB signaling pathway, and IL-6 may play a role in this process.

The mechanism of γ-aminobutyric acid inhibitory on the growth of cholangiocarcinoma cell line

Objective To explore the molecular mechanism of cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) signaling pathway in γ-aminobutyric acid inhibitory on the growth of cholangiocarcinoma QBC939 cell line. Methods QBC939 cells were cultured in different groups and treated withγ-aminobutyric acid (GABA), GABA+ 8 Br (cAMP agonists), GABA+ H89 (PKA antagonist) for 48 hours. (4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay was used to determine the proliferation of QBC939 cells. Annexin V-fluoresceine isothiocyanate (FITC)/propidium iodide (PI) binding assay was used to detect apoptosis in the QBC939 cells. Enzymelinkedimmunosorbentassay (ELISA) assay was detected to the expression of cAMP and PKA. Western blotting was applied to check the expression of PKAI and PKAII and extracellular regulated protein kinases (ERK) proteins in different groups of QBC939 cells. Animal models of cholangiocarcinoma bearing nude mice were established by subcutaneous injection of QBC939 cells and randomized into 2 groups: control and GABA-treated groups. The effect of GABA was evaluated after 5 weeks, including tumor volume. The expression of PKA Ⅰ and PKA Ⅱ and ERK was detected by Western blotting in xenograft tumors. Results MTT and flow cytometry (FCM) assays all showed that the effect of GABA inhibitory on the proliferation and induced apoptosis of QBC939 cells could be antagonized by H89, but not 8 Br. GABA significantly increased the content of cAMP and PKA, the content of cAMP was enhanced by 8 Br, the content of PKA was antagonized by H89. Western blotting analysis showed that GABA significantly down-regulated the expression of PAK I protein (0.087 8±0.003 0 vs. 0.152 1±0.003 0, t=29.687, P<0.05), up-regulated the expression of PKAⅡ, and also decreased the expression of ERK protein protein (0.368 3±0.007 0 vs. 0.468 7±0.010 0, t=13.647, P<0.05). Xenograft tumor volume [ (0.500±0.020 vs. 0.320±0.030) cm3,t=15.354, P<0.05]. The expression of PKAI and ERK were significantly decreased, and PKA II was increased in GABA-treated group as compared with control group. Conclusion GABA may inhibit the growth of cholangiocarcinoma cells QBC939 through cAMP/PKA, down-regulated PAK I, up-regulated PKA II, and decreased the expression of the ERK perhaps is one of its anti-tumor mechanisms. Key words: Bile duct neoplasms; Gamma-aminobutyric acid; Cyclic adenosine monophosphate; Protein kinase A; Extracellular regulated protein kinases

Constraint-induced movement therapy promotes motor function recovery and downregulates phosphorylated extracellular regulated protein kinase expression in ischemic brain tissue of rats.

Motor function impairment is a common outcome of stroke. Constraint-induced movement therapy (CIMT) involving intensive use of the impaired limb while restraining the unaffected limb is widely used to overcome the effects of ‘learned non-use’ and improve limb function after stroke. However, the underlying mechanism of CIMT remains unclear. In the present study, rats were randomly divided into a middle cerebral artery occlusion (model) group, a CIMT + model (CIMT) group, or a sham group. Restriction of the affected limb by plaster cast was performed in the CIMT and sham groups. Compared with the model group, CIMT significantly improved the forelimb functional performance in rats. By western blot assay, the expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi of cerebral ischemic rats in the CIMT group was significantly lower than that in the model group, and was similar to sham group levels. These data suggest that functional recovery after CIMT may be related to decreased expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi.

Cyanidin-3-O-galactoside and Blueberry Extracts Supplementation Improves Spatial Memory and Regulates Hippocampal ERK Expression in Senescence-accelerated Mice

ObjectiveTo investigate whether the antioxidation and the regulation on the Extracellular Regulated Protein Kinases (ERK) signaling pathway are involved in the protective effects of blueberry on central nervous system. Methods30 Senescence-accelerated mice prone 8 (SAMP8) mice were divided into three groups and treated with normal diet, blueberry extracts (200 mg/kg·bw/day) and cyaniding-3-O-galactoside (Cy-3-GAL) (50 mg/kg·bw/day) from blueberry for 8 weeks. 10 SAMR1 mice were set as control group. The capacity of spatial memory was assessed by Passive avoidance task and Morris water maze. Histological analyses on hippocampus were completed. Malondialdehyde (MDA) levels, Superoxide Dismutase (SOD) activity and the expression of ERK were detected. ResultsBoth Cy-3-GAL and blueberry extracts were shown effective functions to relieve cellular injury, improve hippocampal neurons survival and inhibit the pyramidal cell layer damage. Cy-3-GAL and blueberry extracts also increased SOD activity and reduced MDA content in brain tissues and plasma, and increased hippocampal phosphorylated ERK (p-ERK) expression in SAMP8 mice. Further more, the passive avoidance task test showed that both the latency time and the number of errors were improved by Cy-3-GAL treatment, and the Morris Water Maze test showed significant decreases of latency were detected by Cy-3-GAL and blueberry extracts treatment on day 4. ConclusionBlueberry extracts may reverse the declines of cognitive and behavioral function in the ageing process through several pathways, including enhancing the capacity of antioxidation, altering stress signaling. Cy-3-GAL may be an important active ingredient for these biological effects.

Effect of inhibition of the adrenomedullin gene on the growth and chemosensitivity of ovarian cancer cells

Adrenomedullin (AM), a potent vasodilator peptide, is present in various types of tumors. Here, we constructed short hairpin RNA (shRNA) in order to target the AM gene invitro using RNA interference (RNAi) technology. HO8910 ovarian cancer cells were transfected, and the effects of AM on proliferation and chemosensitivity of the cells were examined. RT-PCR, real-time PCR and western blot analysis were performed to detect the AM gene and protein expression. The MTT assay was used to observe the effect of AM on proliferation and chemosensitivity of the cells. Also, the protein levels of bcl-2 and the extracellular regulated protein kinase (ERK) were evaluated by western blot analysis. We found that silencing of the AM gene inhibited the proliferation and increased the chemosensitivity of HO8910 cells, reduced the expression of AM mRNA and protein as well as downregulated bcl-2 and p-ERK expression. We, therefore, conclude that silencing of the AM gene in HO8910 ovarian cancer cells inhibited the proliferation and increased the chemosensitivity of the cells through downregulation of ERK and bcl-2 expression. Thus, anti-AM treatment together with suppression of ERK and bcl-2 expression provides a novel research approach for ovarian cancer.

Parkinson's disease, Parkinsonism and aging

To investigate whether the antioxidation and the regulation on the Extracellular Regulated Protein Kinases (ERK) signaling pathway are involved in the protective effects of blueberry on central nervous system.30 Senescence-accelerated mice prone 8 (SAMP8) mice were divided into three groups and treated with normal diet, blueberry extracts (200 mg/kg·bw/day) and cyaniding-3-O-galactoside (Cy-3-GAL) (50 mg/kg·bw/day) from blueberry for 8 weeks. 10 SAMR1 mice were set as control group. The capacity of spatial memory was assessed by Passive avoidance task and Morris water maze. Histological analyses on hippocampus were completed. Malondialdehyde (MDA) levels, Superoxide Dismutase (SOD) activity and the expression of ERK were detected.Both Cy-3-GAL and blueberry extracts were shown effective functions to relieve cellular injury, improve hippocampal neurons survival and inhibit the pyramidal cell layer damage. Cy-3-GAL and blueberry extracts also increased SOD activity and reduced MDA content in brain tissues and plasma, and increased hippocampal phosphorylated ERK (p-ERK) expression in SAMP8 mice. Further more, the passive avoidance task test showed that both the latency time and the number of errors were improved by Cy-3-GAL treatment, and the Morris Water Maze test showed significant decreases of latency were detected by Cy-3-GAL and blueberry extracts treatment on day 4.Blueberry extracts may reverse the declines of cognitive and behavioral function in the ageing process through several pathways, including enhancing the capacity of antioxidation, altering stress signaling. Cy-3-GAL may be an important active ingredient for these biological effects.