P-p38 MAPK Levels Research Articles

Red nucleus interleukin-1β evokes tactile allodynia through activation of JAK/STAT3 and JNK signaling pathways.

We previously reported that interleukin-1β (IL-1β) in the red nucleus (RN) is involved in pain modulation and exerts a facilitatory effect in the development of neuropathic pain. Here, we explored the actions of signaling pathways, including the Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-κB (NF-κB) pathways, on RN IL-1β-mediated pain modulation. After a single dose of recombinant rat IL-1β (rrIL-1β, 10ng) injected into the RN in normal rats, a tactile allodynia was evoked in the contralateral but not ipsilateral hindpaw, commencing 75min and peaking 120min postinjection. Up-regulated protein levels of phospho-STAT3 (p-STAT3) and p-JNK were observed in the RN 120min after rrIL-1β injection, the increases of p-STAT3 and p-JNK were blocked by anti-IL-1β antibody. However, the expression levels of p-ERK, p-p38 MAPK, and NF-κB in the RN were not affected by rrIL-1β injection. RN neurons and astrocytes contributed to IL-1β-evoked up-regulation of p-STAT3 and p-JNK. Further studies demonstrated that injection of the JAK2 antagonist AG490 or JNK antagonist SP600125 into the RN 30min prior to the administration of rrIL-1β could completely prevent IL-1β-evoked tactile allodynia, while injection of the ERK antagonist PD98059, p38 MAPK antagonist SB203580, or NF-κB antagonist PDTC did not affect IL-1β-evoked tactile allodynia. In conclusion, our data provide additional evidence that RN IL-1β is involved in pain modulation, and that it exerts a facilitatory effect by activating the JAK/STAT3 and JNK signaling pathways.

Effects of programmde cell death 4 on growth, colony forming ability and apoptosis of bladder cancer cells

Objective To investigate the effects of programmde cell death 4 (PDCD4) on the growth, clonogenic ability and apoptosis of bladder cancer cells. Methods Lentivirus expressing PDCD4 in bladder cancer cell line T24 as overexpression group, at the same time, the cells infected with lentivirus were divided into blank group, the T24 cells without treatment were used as the control group. The levels of PDCD4 in cells were detected by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) and Western blotting. The cell growth curve was plotted by trypan blue staining, the A value of cells was detected by methyl thiazol tetrazolium (MTT), apoptosis was detected by flow cytometry, the levels of p38 mitogen activated protein kinase (p38MAPK), phosphorylation-p38MAPK (p-p38MAPK), signal transducer and activators of transcription 3 (STAT3), phosphorylation-STAT3 (p-STAT3) and cleaved cysteinyl aspartate-specific protease (Cleaved Caspase)-3 were detected by Western blotting. Results The levels of PDCD4 gene and protein in the overexpressed group were significantly higher than those in the control group (t1=12.249, P1=0.000, t2=11.601, P2=0.000) The number of cells in the overexpression group was significantly lower than that in the control group from 3 d (t1=4.075, P1=0.015, t2=6.665, P2=0.003, t3=6.340, P3=0.003). The optical density value (A value) in the over expression group was significantly lower than that in the control group, while the apoptosis rate was significantly higher in the overexpression group than in the control group (t=3.725, P=0.020). The levels of p-p38MAPK and Cleaved Caspase-3 in the overexpression group increased significantly, while the level of p-STAT3 in the cells decreased significantly (t1=10.136, P1=0.001, t2=11.867, P2=0.000, t3=6.662, P3=0.003). The levels of PDCD4, p-p38MAPK, Cleaved Caspase-3, p-STAT3, and A value, apoptosis rate in the blank group were not significantly different from those in the control group. Conclusion PDCD4 inhibits the growth of bladder cancer cells, promote cell apoptosis, reducing cell cloning ability, inhibition of phosphorylation of STAT3 in cells, promoting the phosphorylation of p38MAPK in cells, promoting the activation of Caspase-3 in cells. Key words: Programmde cell death 4; Bladder cancer; Apoptosis; Growth

Atorvastatin Pretreatment Attenuates Ischemic Brain Edema by Suppressing Aquaporin 4

Background: Cerebral edema, a serious complication of acute cerebral infarction, has a crucial impact on morbidity and mortality in the early stage of cerebral infarction. And aquaporin 4 (AQP4), a bidirectional water transporting protein, plays a pivotal role in edema formation. At experimental model, it has proven that atorvastatin could exert pleiotropic neuroprotection on acute cerebral infarction independent of its cholesterol-lowering action. It was a common protective manifestation that atorvastatin can reduce the infarct volume and cerebral edema. However, little is known about atorvastatin improving ischemic brain edema by regulating AQP4 expression. This study intended to investigate the neuroprotection effects of atorvastatin pretreatment in rats with cerebral ischemia and further explore the potential relationship between atorvastatin and AQP4 expression. Methods: Fifty-one adult male Sprague Dawley rats were randomly divided into 3 groups: sham, middle cerebral artery occlusion (MCAO), and atorvastatin pretreatment (Ator) group. For Ator group, 20 mg/kg of atorvastatin injectable suspension was administered once for 7days by gavage before operation, whereas the others were administered the same volume of saline matching. Except for sham group, MCAO and Ator groups were subjected to permanent MCAO by modified intraluminal suture method. Infarct volume, neurological deficit, brain water content (BWC), immunohistochemistry, western blot, and polymerase chain reaction (PCR) were measured at 24 hours after MCAO. Results: Compared with sham group, the mNSS, infarct volume, and BWC of ischemic hemisphere were significantly increased (P < 0.001) in MCAO group. Positive cells and protein levels of p-p38MAPK and AQP4 in peri-infarction were significantly increased (P < 0.01). The mRNA levels of p38MAPK and AQP4 were also prominently upregulated (P < 0.01). Interestingly, preadministration of atorvastatin dramatically decreased infarct volume and the BWC of ischemic hemisphere compared with MCAO group (P < 0.05). The overexpressions of p-p38MAPK and AQP4 in peri-infarction were significantly decreased (P < 0.05) and their mRNA levels were downregulated by atorvastatin pretreatment (P < 0.05). Neurological deficits were also dramatically improved (P < 0.001). Conclusion: To the best of our knowledge, this is the first study that demonstrates an effect of atorvastatin on expression of AQP4, and we propose that decreased AQP4 expression through a p38MAPK-suppression pathway may be the mechanism of atorvastatin alleviating ischemic cerebral edema.

Small interfering RNA-mediated LPXN silencing suppresses proliferation and enhances drug sensitivity of human acute monocytic leukemia SHI-1 cells in vitro

To investigate the effect of silencing LPXN expression by RNA interference on the proliferation and drug sensitivity of human acute monocytic leukemia SHI-1 cells in vitro. Small interfering RNA (siRNA) sequences targeting LPXN were designed and transiently transfected in SHI-1 cells via Lipofectamine 2000, and the most efficient siRNA sequence for LPXN silencing was identified using Western blotting. The protein expression levels of LPXN, p-JNK, p-P38 MAPK and p-ERK were in the cells transfected with the selected siRNA were detected using Western blotting, and the cell proliferation changes were assessed using CCK-8 reagent. LPXN silencing by siRNA transfection resulted in significant proliferation suppression in SHI-1 cells with an inhibition rate of(27.04±2.05) % (P < 0.05). Western blotting showed that treatment of the siRNA-transfected SHI-1 cells with 0-25 μmol/L curcumin or with 0-2.0 μmol/L Ara-C further increased the cell inhibition rate and obviously enhanced the expressions of p-P38 MAPK and p-JNK without significantly affecting p-ERK expression. Down-regulation of LPXN expression by siRNA transfection can suppress the proliferation and increase the drug sensitivity of SHI-1 cells probably by activating JNK and P38 MAPK.

Role of p38MAPK signaling pathway in rats with phantom limb pain

To investigate the role of p38MAPK signal pathway in spinal cord and dorsal root ganglion (DRG) in rats with phantom limb pain and the effects of specific inhibitors. Methods: Healthy adult male SD rats (n=48) were cut off one side of the sciatic under anesthesia to establish a model of phantom limb pain. In addition, the healthy rats were taken as a sham group (group S, n=24). The animals were scored by observing the action of chewing (0=no chewing, 13=the worst chewing) after the operation and were sacrificed on the following day after the operation. The successful model of phantom limb pain were randomly divided into 2 groups: a phantom limb pain group (group P, n=24) and a phantom limb pain plus inhibitor group (group P+I, n=24). SB203580 was given to the rat at 0.8 mg/kg on every Monday until the rats were sacrificed, the rest of the rats received an equal amount of saline. Eight rats from each group were randomly taken for the determination of levels of P-p38MAPK in spinal cord and DRG before administration and on the 4th, 6th, 8th weekend following the administration, respectively. Results: In the sham group, no animal developed chewing. Meanwhile, rats in successful model of phantom limb pain group began chewing from the 2nd day after operation with scores at eight to eleven. The chewing scores in the P+I group were reduced after the treatment. Compared with group S, P-p38MAPK levels were elevated in groups of P and P+I (P<0.05 or P<0.01). Compared with group P, P-p38MAPK level was decreased in the group P+I (P<0.05 or P<0.01). Conclusion: P38MAPK signal pathway involves in the development of phantom limb pain.

Ginkgo Biloba L. Extract Reduces H2O2-Induced Bone Marrow Mesenchymal Stem Cells Cytotoxicity by Regulating Mitogen-Activated Protein Kinase (MAPK) Signaling Pathways and Oxidative Stress.

BackgroundThe oxidative stress environment of pathological tissue has an adverse effect on the survival of bone marrow mesenchymal stem cells (BMSCs) transplantation. Ginkgo biloba L. extract (EGB) has a potent antioxidant effect. In this research, we assessed the protective effects of EGB and EGB-Containing Serum (EGB CS) on BMSCs against injury induced by hydrogen peroxide (H2O2).Material/MethodsBMSCs were pretreated with EGB or EGB CS and treated with H2O2. The cell counting kit-8 (CCK-8) method was utilized to detect cell viability. The DCFH-DA Fluorescent Kit method was used to detect intracellular ROS level. Malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and (CAT) were determined. The Hoechst staining assay and qRT-PCR assay were utilized to evaluate the effect of EGB on cell apoptosis. Mitogen-activated protein kinases (MAPKs) signaling pathway were detected by western blot analysis.ResultsCompared to the H2O2 group, the number of apoptotic cells in the EGB and EGB CS pretreated groups significantly decreased. The mRNA expression ratio of Bax/Bcl-2 was also decreased. EGB and EGB CS can reduce the production of ROS in BMSCs exposed to H2O2. SOD, GSH-Px and CAT activities were significantly higher compared with those with H2O2 group. Furthermore, EGB or EGB CS pretreatment decreased the protein levels of p-p38MAPK and p-JNK in BMSCs compared to the H2O2 group.ConclusionsOur findings suggested that EGB and EGB CS have protective effect on BMSCs against oxidative stress injury and increase the survival rate of BMSCs transplantation by regulating p38MAPK and JNK signaling.

Correction: Treatment combining aliskiren with paricalcitol is effective against progressive renal tubulointerstitial fibrosis via dual blockade of intrarenal renin

[This corrects the article DOI: 10.1371/journal.pone.0181757.].

Estrogen alleviates neuropathic pain induced after spinal cord injury by inhibiting microglia and astrocyte activation

Neuropathic pain after spinal cord injury (SCI) is developed in about 80% of SCI patients and there is no efficient therapeutic drug to alleviate SCI-induced neuropathic pain. Here we examined the effect of estrogen on SCI-induced neuropathic pain at below-level and its effect on neuroinflammation as underlying mechanisms. Neuropathic pain is developed at late phase after SCI and a single dose of 17β-estradiol (100, 300 μg/kg) were administered to rats with neuropathic pain after SCI through intravenous injection. As results, both mechanical allodynia and thermal hyperalgesia were significantly reduced by 17β-estradiol compared to vehicle control. Both microglia and astrocyte activation in the lamina I and II of L4-5 dorsal horn was also inhibited by 17β-estradiol. In addition, the levels of p-p38MAPK and p-ERK known to be activated in microglia and p-JNK known to be activated in astrocyte were significantly decreased by 17β-estradiol. Furthermore, the mRNA expression of inflammatory mediators such as Il-1β, Il-6, iNos, and Cox-2 was more attenuated in 17β-estradiol-treated group than in vehicle-treated group. Particularly, we found that the analgesic effect by 17β-estradiol was mediated via estrogen receptors, which are expressed in dorsal horn neurons. These results suggest that 17β-estradiol may attenuate SCI-induced neuropathic pain by inhibiting microglia and astrocyte activation followed inflammation.

Beneficial effect of baicalin on insulin sensitivity in adipocytes of diet-induced obese mice

AimsAlthough baicalin has been shown to increase glucose uptake and insulin sensitivity in skeletal muscle of mice, there is no literature available about the effect of baicalin on insulin sensitivity in adipocytes of diet-induced obese mice. MethodsIn the present study, diet-induced obese mice were given 50 mg/kg baicalin intraperitoneally (i.p.) once a day for 21 days, and 3T3-L1 cells were treated with 100, 200, 400 μM baicalin for 3 h. Then insulin resistance indexes and insulin signal protein levels were examined to elucidate whether baicalin increased glucose uptake and GLUT4 translocation in adipocytes of diet-induced obese mice. ResultsThe present findings showed that administration of baicalin decreased food intake, body weight, HOMA-IR and p-p38 MAPK and pERK levels, but enhanced pAKT and PGC-1α contents, as well as GLUT4 mRNA, PGC-1α mRNA expression in adipocytes, and reversed high fat diet-induced glucose intolerance, hyperglycemia and insulin resistance in diet-induced obese mice. Moreover, baicalin treatment increased GLUT4 concentration in plasma membranes of adipocytes. ConclusionsThese data demonstrated that baicalin accelerated GLUT4 translocation from intracellular membrane compartments to plasma membranes in adipocytes. Baicalin plays a significant role in elevation of glucose uptake and insulin sensitivity to promote glucose clearance.

The role of 19S proteasome associated deubiquitinases in activity-dependent hippocampal synaptic plasticity

Posttranslational modification and degradation of proteins by the ubiquitin-proteasome system (UPS) is crucial to synaptic transmission. It is well established that 19S proteasome associated deubiquitinases (DUBs) reverse the process of ubiquitination by removing ubiquitin from their substrates. However, their potential contribution to hippocampal synaptic plasticity has not been addressed in detail. Here, we report that inhibition of the 19S proteasome associated DUBs, ubiquitin C-terminal hydrolase 5 (UCHL5) and ubiquitin-specific peptidase 14 (USP14) by b-AP15 results in an accumulation of polyubiquitinated proteins and a reduction of monomeric ubiquitin without overt effects on 26S proteasome activity. b-AP15 led to a suppression of mTOR-p70S6K signaling and an increase in levels of p-p38 MAPK, two pathways essentially involved in establishing various forms of activity-dependent plasticity. Additionally, b-AP15 impaired the induction of late-phase long-term potentiation (L-LTP), induced the transformation of mGluR-mediated protein synthesis-independent long-term depression (early-LTD) to L-LTD and promoted heterosynaptic stabilization through synaptic tagging/capture (STC) in the hippocampal CA1 region of mice. The activity of 19S proteasome associated DUBs was also required for the enhancement of short-term potentiation (STP) induced by brain-derived neurotrophic factor (BDNF). Altogether, these results indicate an essential role of 19S proteasome associated DUBs in regulating activity-dependent hippocampal synaptic plasticity.

Suppressive effects of berberine on atherosclerosis via downregulating visfatin expression and attenuating visfatin-induced endothelial dysfunction.

Berberine (BBR) possesses significant anti-atherosclerosis properties. Visfatin is one of the most promising biomarkers of incoming atherosclerosis. However, research on the effect of BBR on regulating visfatin expression in atherogenesis remains largely unknown. In this study, we investigated the effects of BBR on visfatin expression and atherogenesis in apolipoprotein E knockout (ApoE−/−) mice. The effect of BBR on attenuating visfatin-induced endothelial dysfunction was also evaluated in cultured human umbilical vein endothelial cells (HUVECs). In vivo experiments showed that BBR treatment (5 mg/kg/day) significantly reduced the serum levels of visfatin, lipid, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), the protein expression of visfatin, p-p38 MAPK and p-c-Jun N-terminal kinase (JNK) in mice aorta and the distribution of visfatin in the atherosclerotic lesions in ApoE−/− mice fed with a Western diet. In addition, in vitro experiments indicated that visfatin (100 µg/l) significantly increased apoptosis, the contents of IL-6 and TNF-α, the protein levels of p-p38 MAPK, p-JNK and Bax in HUVECs, which were reversed by BBR administration (50 µmol/l). Our findings suggest that BBR significantly ameliorates Western diet-induced atherosclerosis in ApoE−/− mice via downregulating visfatin expression, which is related to the inhibition of p38 MAPK and JNK signaling pathways and subsequent suppression of visfatin-induced endothelial dysfunction.

Complete inhibition of phosphatase and tensin homolog promotes the normal and oxygen-glucose deprivation/reperfusion-injured PC12 cells to cell death.

Introduction: Lipid phosphatase and tensin homolog deleted from chromosome 10 (PTEN) antagonizes phosphoinositide 3-kinase (PI3K)/AKT cell survival pathway. The effect of PTEN inhibitors has been rarely examined on cell survival following reperfusion injury. In this study, we investigated the neuroprotective effect of SF1670, as a new PTEN inhibitor, on an in vitro stroke-like model. Methods: PC12 cells were exposed to oxygen-glucose deprivation/reperfusion (OGD/R). The cells were treated in five conditions as follows: normoxic normoglycemic (NO/NG); 60 minutes OGD; 60 minutes OGD and 6 h reperfusion (OGD/R); OGD/R treated with 10 µM SF1670 (OGD/R-SF), and NO/NG treated with 10 µM SF1670 (NO/NG-SF). Then, phosphorylation levels of AKT, P38 in PC12 cells were measured by immunoblotting. The cell viability was also determined by colorimetric assay. Results: The results of immunoblotting revealed that following OGD/R the levels of phospho-AKT (p-AKT) significantly decreased, compared to NO/NG cells (P < 0.05). However, the ratio of p-AKT/total AKT significantly increased in the presence of SF1670 in the OGD/R-SF group, compared to the OGD/R condition. On the other hand, SF1670 significantly reduced the p-P38 MAPK and p-JNK levels, compared to OGD/R cells. Moreover, cell viability significantly decreased in the OGD and OGD/R condition compared to NO/NG cells. Surprisingly, SF-treated cells (OGD/R-SF and NO/NG-SF group) showed low cell viability compared to NO/NG condition. Conclusion: Overall, our results demonstrated that complete inhibition of phosphatase activity of PTEN not only did not exhibit neuroprotective effect but also promoted PC12-deprived cells to death.

Effect of Baicalein on GLUT4 Translocation in Adipocytes of Diet-Induced Obese Mice

Background/Aims: Although baicalein has been shown to increase insulin sensitivity in liver of mice, there is no literature available about the effect of baicalein on glucose transporter 4 (GLUT4) translocation from intracellular membrane pools to plasma membranes in adipocytes of diet-induced obese mice. Methods: In the present study, the obese model was induced in mice fed a high fat diet (20% carbohydrates, 21% protein and 59% fat) for 16 weeks. The diet-induced obese mice were given 20mg/kg baicalein intraperitoneally (i.p.) once a day for 21 days. The plasma insulin was measured by enzyme-linked immunosorbent assay. Fasting blood glucose and insulin resistance indexes were measured by glucose tolerance test (GTT). The expression levels of PGC-1α, UCP1, GLUT4, PPARγ, pP38MAPK, pERK and pAKT in adipocytes were determined by quantitative real-time polymerase chain reaction and western blotting. Results: The present findings showed that administration of baicalein decreased pP38MAPK, pERK and PPARγ levels, but enhanced pAKT, PGC-1α and UCP1 contents as well as GLUT4 expression in adipocytes, and reversed high fat diet-induced glucose intolerance, hyperglycemia and insulin resistance in diet-induced obese mice. Moreover, baicalein treatment increased GLUT4 concentration in plasma membranes of adipocytes, i.e. baicalein may prevent insulin resistance through the GLUT4 translocation from intracellular membrane compartments to plasma membranes in adipocytes. Conclusion: These results suggest that baicalein is a powerful and promising agent for treatment of obesity and insulin resistance via Akt/GLUT4 pathway.

Activiated galanin receptor 2 attenuates insulin resistance in skeletal muscle of obese mice

The results of our and other's studies showed that activation of galanin receptor 1 could mitigate insulin resistance via promoting glucose transporter 4 (GLUT4) expression and translocation in the skeletal muscle of rats. But no literature are available regarding the effect of galanin receptor 2 (GALR2) on insulin resistance in skeletal muscle of type 2 diabetes. Herein, in this study we intended to survey the effect of GALR2 and its signal mechanisms in the mice with high fat diet-induced obese. The mice were intraperitoneally injected with vehicle, GALR2 agonist M1145 and antagonist M871 respectively once a day for continuous 21 days. The skeletal muscles were processed for determination of glucose uptake, and GLUT4 mRNA and protein expression levels. The PGC-1α, AKT, p38MAPK, AS160, pAKT, pP38MAPK and pAS160 expression levels were quantitatively assessed too. We found that pharmacological activation of GALR2 enhanced energy expenditure, and increased GLUT4 expression and translocation in skeletal muscle of mice during high-fat diet regimens. Activation of GALR2 alleviated insulin resistance through P38MAPK/PGC-1α/GLUT4 and AKT/AS160/GLUT4 pathway in the skeletal muscle of mice. Overall, these results identify that GALR2 is a regulator of insulin resistance and activation of GALR2 represents a promising strategy against obesity-induced insulin resistance.

Effect of Chinese medicine of nourishing kidney and clearing liver on intermittent hypoxia induced injury model of HUVECs through p38MAPK/NF-κB signaling pathway

This study aims to explore the intervention effect of Chinese medicine of nourishing kidney and clearing liver on intermittent hypoxia(IH) induced injury model of HUVECs through p38MAPK/NF-κB signaling pathway in vitro. HUVECs injury model was induced by modified IH treatment. The effective components of Chinese medicine of nourishing kidney and clearing liver including isochteroside, aucubin and ligustrazine were used as intervention drugs. The optimal compatibility concentration of them was screened in vitro, and then the optimal compatibility concentration was selected as the intervention dose to observe the effect on p38MAPK/NF-κB signaling pathway in IH induced injury model of HUVECs. The results showed that isochnae, aucubin and ligustrazine had the best anti-inflammatory effect at concentration of 0.01 mg•L-1. NF-κB p65 and p-IκB in the nucleus in IH group were significantly higher than those in the normal control(N) group and the other groups. Immunofluorescence staining showed significant translocation of NF-κB p65 nucleus in IH group, and HUVECs adhesion capacity in IH group was increased significantly. As compared with IH group, the expression levels of p-p38MAPK, NF-κB p65 and p-IκB in p38MAPK inhibitor(INH) group and Chinese medicine of nourishing kidney and clearing liver(GDC) group were significantly decreased, and HUVECs adhesion capacity in INH group and GDC group was significantly inhibited as well. The optimal concentration of Chinese medicine of nourishing kidney and clearing liver can inhibit the phosphorylation of p38MAPK, and then inhibit the nuclear translocation and transcription function of NF-κB. This may be the mechanism of the protective effect of Chinese medicine on IH induced injury model of HUVECs.

4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol} (TIMBD) suppresses HIV1-gp120 mediated production of IL6 and IL8 but not CCL5

Human immunodeficiency virus (HIV) has been associated with inflammatory effects that may potentially result in neurodegenerative changes and a number of newer chemotherapeutic agents are being tested to ameliorate these effects. In this study, we investigated the anti-neuroinflammatory activity of a novel resveratrol analog 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol} (TIMBD) against HIV1-gp120 induced neuroinflammation in SVG astrocytes. SVG astrocytic cells were pretreated with TIMBD or resveratrol (RES) and then transfected with a plasmid encoding HIV1-gp120. The mRNA and protein expression levels of proinflammatory cytokines IL6, IL8 and CCL5 were determined. Protein expression levels of NF-κB, AP1, p-STAT3, p-AKT, p-IKKs and p-p38 MAPK were also determined. TIMBD inhibited gp120-induced RNA and protein expression levels of IL6 and IL8, but not that of CCL5 in SVG astrocytes. Moreover, TIMBD attenuated gp120-induced phosphorylation of cJUN, cFOS, STAT3, p38-MAPK, AKT and IKKs, and the nuclear translocation of NF-κB p-65 subunit whereas RES mostly affected NF-κB protein expression levels. Our results suggest that TIMBD exerts anti-inflammatory effects better than that of RES in SVG astrocytes in vitro. These effects seem to be regulated by AP1, STAT-3 and NF-κB signaling pathways. TIMBD may thus have a potential of being a novel agent for treating HIV1-gp120-mediated neuroinflammatory diseases.

Treatment combining aliskiren with paricalcitol is effective against progressive renal tubulointerstitial fibrosis via dual blockade of intrarenal renin

The aim of this study was to assess any potential additive effects of a treatment combining aliskiren with paricalcitol on reducing renal fibrosis. C57BL/6J mice were treated individually with aliskiren and/or paricalcitol until 7 days after initiation of unilateral ureteral obstruction (UUO).In obstructed kidneys of UUO mice, monotherapy with aliskiren or paricalcitol significantly attenuated interstitial fibrosis, collagen IV accumulation, and α-smooth muscle actin- and terminal deoxynucleotidyl transferase-mediated biotin nick end-labeling-positive cells. The combination treatment showed additive efficacy in inhibition of these parameters. Renal NADPH oxidase (Nox)1 and Nox2 were significantly decreased by aliskiren or paricalcitol alone or in combination, while renal Nox4 expression was significantly reduced by paricalcitol mono- or combination treatment. Increased levels of p-Erk and p-p38 MAPK, and NF-κB in UUO kidneys were also significantly reduced by either aliskiren or paricalcitol treatment alone or in combination. Aliskiren or paricalcitol monotherapy significantly reduced the expression of (pro)renin receptor in UUO kidneys. In addition, aliskiren tended to augment renin expression in UUO kidneys, but paricalcitol reduced its expression level. The combination treatment effectively blocked both (pro)renin receptor and renin expression induced by aliskiren, and resulted in a further reduction of the renal expression of angiotensin II AT1 receptor. Aliskiren failed to increase the expression of vitamin D receptor in UUO kidneys, but the combination treatment restored its expression level. Taken together, a treatment combining aliskiren with paricalcitol better inhibits UUO-induced renal injury. The mechanism of this synergy may involve more profound inhibition of the intrarenal renin-angiotensin system.

HMGB1-TLR4 Axis Plays a Regulatory Role in the Pathogenesis of Mesial Temporal Lobe Epilepsy in Immature Rat Model and Children via the p38MAPK Signaling Pathway.

The HMGB1-TLR4 axis is activated in adult mouse models of acute and chronic seizure. Nevertheless, whether HMGB1 was involved in the pathogenesis of mesial temporal lobe epilepsy (MTLE) remains unknown. In this study, we first measured the dynamic expression patterns of HMGB1 and TLR4 in the hippocampi of a rat model and in children with MTLE, as well as the levels of TNF-α and IL-1β. In addition, HMGB1 was added to mimic the process of inflammatory response in neurons. Neuronal somatic size and dendritic length were measured by immunohistochemistry and digital imaging. The results showed that the expression of HMGB1 and TLR4 as well as the levels of TNF-α and IL-1β were higher in the three stages of MTLE development in the rat model and in the children with MTLE. HMGB1 increased the levels of TNF-α and IL-1β, upregulated the protein level of p-p38MAPK and promoted the growth of cell somatic size and dendritic length in neurons. Pre-treatment with p38MAPK inhibitor SB203580 decreased the levels of TNF-α and IL-1β, while downregulation of TLR4 significantly reduced HMGB1-induced p38MAPK signaling pathway activation. These data demonstrated that the HMGB1-TLR4 axis may play an important role in the pathogenesis of MTLE via the p38MAPK signaling pathway.

The effects of pleiotrophin in proliferative vitreoretinopathy.

The purpose of our study was to investigate the effects of pleiotrophin (PTN) in proliferative vitreoretinopathy (PVR) both in vitro and in vivo. Immunofluorescence was used to observe the PTN expression in periretinal membrane samples from patients with PVR and controls. ARPE-19 cells were exposed to TGF-β1. The epithelial-to-mesenchymal transition (EMT) of the ARPE-19 cells was confirmed by observed morphological changes and the increased expression of α-SMA and fibronectin at both the mRNA and protein levels. We used specific small interfering (si)RNA to knock down the expression of PTN. The subsequent effects of PTN inhibition were assessed with regard to the EMT, migration, proliferation, cytoskeletal arrangement, TGF-β signaling, PTN signaling, integral tight junction protein expression (e.g., claudin-1 and occludin), and p38 MAPK and p-p38 MAPK levels. Additionally, a PVR rat model was established by the intravitreal injection of ARPE-19 cells transfected with PTN-siRNA and was evaluated accordingly. PTN was highly expressed in PVR membranes compared to controls. PTN knockdown attenuated the TGF-β1-induced migration, proliferation, cytoskeletal rearrangement, and expression of EMT markers such as α-SMA and fibronectin in the ARPE-19 cells, and these effects may have been mediated through p38 MAPK signaling pathway activation. PTN silencing inhibited the up-regulation of claudin-1 and occludin stimulated by TGF-β1, and PTN knockdown inhibited the proliferative aspects of severe PVR in vivo. PTN is involved in the process of EMT induced by TGF-β1 in human ARPE-19 cells in vitro, and PTN knockdown attenuated the progression of experimental PVR in vivo. These findings provide new insights into the pathogenesis of PVR.

HYP-17, a novel voltage-gated sodium channel blocker, relieves inflammatory and neuropathic pain in rats

Clinical and experimental studies suggest that voltage-gated sodium channels (VGSCs) play a key role in the pathogenesis of neuropathic pain and that blocking agents against these channels can be potentially therapeutic. In the current study, we investigated whether a novel compound, (-)-2-Amino-1-(4-((4-chlorophenyl)(phenyl)methyl)piperazin-1-yl)-propan-1-one(HYP-17), binds to VGSCs and evaluated its inhibitory effect on Na+ currents of the rat dorsal root ganglia (DRG) sensory neurons and its analgesic effect on inflammatory and neuropathic pain. HYP-17 (10μM) reduced both the tetrodotoxin-sensitive (TTX-S) and the TTX-resistant (TTX-R) currents in DRG sensory neurons. However, neither the voltage-dependent activation curves nor the steady-state inactivation curves for TTX-S and TTX-R currents were changed by HYP-17. In rats injected with 5% formalin under the plantar surface of the hind paw, HYP-17 (10μg) significantly reduced both the early and late phase spontaneous pain behaviors. Systemic injection with HYP-17 (60mg/kg, i.p.) also significantly relieved the mechanical, cold, and warm allodynia induced by rat tail nerve injury. Furthermore, HYP-17 (60mg/kg, i.p.) significantly relieved the central neuropathic pain induced by spinal cord injury (SCI), and inhibited c-Fos expression in lumbar (L) 4–L5 spinal segments. Electrophysiological study showed that HYP-17 significantly attenuated the hyper-responsiveness of lumbar dorsal horn neurons. In addition, HYP-17 significantly reduced the levels of pp38MAPK and p-JNK in microglia and astrocytes, respectively, in the L4-L5 spinal dorsal horn. Therefore, our results indicate that HYP-17 has potential analgesic activities against nociceptive, inflammatory and neuropathic pain.