Cyanidin-3-O-glucoside plays a protective role against renal ischemia/ reperfusion injury via the JAK/STAT pathway

Purpose: To investigate the role of cyanidin-3-O-glucoside (C3G) in renal ischemia/reperfusion (I/R) injury and the potential mechanisms. Methods: Mouse models were established by clamping the left renal vessels, and in vitro cellular models were established by hypoxic reoxygenation. Results: Renal dysfunction and tissue structural damage were significantly higher in the I/R group. After treatment with different concentrations of C3G, the levels of renal dysfunction and tissue structural damage decreased at different levels. And its protective effect was most pronounced at 200 mg/kg. The use of C3G reduced apoptosis as well as the expression of endoplasmic reticulum stress (ERS)-related proteins. Hypoxia/reoxygenation (H/R)-induced apoptosis and ERS are dependent on oxidative stress in vitro. In addition, both AG490 and C3G inhibited the activation of JAK/STAT pathway and attenuated oxidative stress, ischemia-induced apoptosis and ERS. Conclusions: The results demonstrated that C3G blocked renal apoptosis and ERS protein expression by preventing reactive oxygen species (ROS) production after I/R via the JAK/STAT pathway, suggesting that C3G may be a potential therapeutic agent for renal I/R injury.

Colorectal cancer cells induce the formation of cancer-associated fibroblasts by activating the ERK signaling pathway in fibroblasts / 南方医科大学学报

OBJECTIVE@#To investigate the mechanism by which conditioned medium of colorectal cancer cells promotes the formation of cancer-associated fibroblasts (CAFs).@*METHODS@#Normal human colorectal fibroblasts (CCD-18Co cells) in logarithmic growth phase were treated with the conditioned media of colorectal cancer HCT116 cells (HCT116-CM) or Caco-2 cells (Caco-2-CM) alone or in combination with 300 nmol/L ERK inhibitor SCH772984. The expression levels of CAFs-related molecular markers were detected in the treated cells with real-time quantitative PCR (RT- qPCR) and immunofluorescence assay, and the changes in cell proliferation, colony formation and migration were assessed with RTCA, colony formation and wound healing assays; Western blotting was performed to detect the activated signaling pathways in the fibroblasts and the changes in CAFs formation after blocking of the signaling pathway.@*RESULTS@#HCT116-CM and Caco-2-CM significantly upregulated mRNA expression levels of CAFs markers (including α-SMA, FAP, FN and TGF-β) in CCD-18Co cells, and strongly promoted fibroblast transformation into CAFs (P < 0.05). The two conditioned media also promoted the proliferation, colony formation and migration of CCD-18Co cells (P < 0.05) and significantly increased the levels of α-SMA protein and ERK phosphorylation in the cells (P < 0.05). The ERK inhibitor SCH772984 obviously inhibited the expression of α-SMA and the transformation of CCD-18Co cells into CAFs induced by the conditioned medium of colorectal cancer cells (P < 0.05).@*CONCLUSION@#Colorectal cancer cells may induce the formation of colorectal CAFs by activating the ERK pathway in the fibroblasts.

Y-box-binding protein 1 mediates sorafenib resistance via the extracellular signal regulated-protein kinase pathway in hepatoma cells / 中华肝脏病杂志

Objective: To investigate the effect and possible mechanism of Y-box-binding protein 1 (YB-1) on sorafenib resistance in hepatoma cells. Methods: Lentiviral vectors with YB-1 overexpression and knockdown were constructed, respectively, to stimulate human hepatoma cell lines (HepG2 and Huh7) alone or in combination with sorafenib.The overexpression part of the experiment was divided into four groups: overexpression control group (Lv-NC), YB-1 overexpression group (Lv-YB-1), overexpression control combined with sorafenib resistance group (Lv-NC+sorafenib), YB-1 overexpression combined with sorafenib resistance group (Lv-YB-1 + sorafenib). The knockdown part of the experiment was also divided into four groups: knockdown control group (Lv-shNC), YB-1 knockdown group (Lv-shYB-1), knockdown control combined with sorafenib resistance group (Lv-shNC + sorafenib), YB-1 knockdown combined with sorafenib resistance group (Lv-shYB-1 + sorafenib). The occurrence of cell apoptosis was detected by TUNEL. The protein expression levels of phosphorylated (p)-ERK and ERK, key proteins in the extracellular regulatory protein kinase (ERK) signaling pathway, were detected by Western blot and quantified by ImageJ software. Subcutaneous tumorigenesis experiments were performed in nude mice. The effect of YB-1 on the efficacy of sorafenib was verified in vivo. The comparison between the two sets of data was carried out by an independent sample t-test. One-way ANOVA was used for comparisons between the three groups of data above. Results: Sorafenib had accelerated the occurrence of apoptosis in hepatoma cells, while YB-1 overexpression had inhibited cell apoptosis, and at the same time also inhibited the apoptosis-accelerating impact of sorafenib. On the contrary, YB-1 knockdown accelerated cell apoptosis and amplified the induction effect of sorafenib on apoptosis. Furthermore, sorafenib resistance had down-regulated p-ERK levels (HepG2: Lv-NC 0.685 ± 0.143, Lv-NC + sorafenib 0.315 ± 0.168, P < 0.05; Huh7: Lv-NC 0.576 ± 0.078, Lv-NC + sorafenib 0.150 ± 0.131, P < 0.01), whereas YB-1 overexpression had inhibited sorafenib resistance p-ERK reduction (HepG2: Lv-NC + sorafenib 0.315 ± 0.168, Lv-YB-1 + sorafenib 0.688 ± 0.042, P < 0.05; Huh7: Lv-NC + sorafenib 0.150 ± 0.131, Lv-YB-1 + sorafenib 0.553 ± 0.041, P < 0.05). YB-1 knockdown further increased sorafenib-induced p-ERK downregulation (HepG2: Lv-shNC + sorafenib 0.911 ± 0.252, Lv-shYB-1 + sorafenib 0.500 ± 0.201, P < 0.05; Huh7: Lv-shNC + sorafenib 0.577 ± 0.082, Lv-shYB-1 + sorafenib 0.350 ± 0.143, P < 0.05), which was further verified in naked mice (Lv-shNC + sorafenib 0.812 ± 0.279, Lv-shYB-1 + sorafenib 0.352 ± 0.109, P < 0.05). Conclusion: YB-1 mediates the occurrence of sorafenib resistance via the ERK signaling pathway in hepatoma cells.

Acteoside promotes autophagy and apoptosis of hepatoma cells by regulating JNK signaling pathway / 中国中药杂志

This study explored the molecular mechanism of acteoside against hepatoma 22(H22) tumor in mice through c-Jun N-terminal kinase(JNK) signaling pathway. H22 cells were subcutaneously inoculated in 50 male BALB/c mice, and then the model mice were classified into model group, low-dose, medium-dose, and high-dose acteoside groups, and cisplatin group. The administration lasted 2 weeks for each group(5 consecutive days/week). The general conditions of mice in each group, such as mental status, diet intake, water intake, activity, and fur were observed. The body weight, tumor volume, tumor weight, and tumor-inhibiting rate were compared before and after administration. Morphological changes of liver cancer tissues were observed based on hematoxylin and eosin(HE) staining, and the expression of phosphorylated(p)-JNK, JNK, B-cell lymphoma-2(Bcl-2), Beclin-1, and light chain 3(LC3) in each tissue was detected by immunohistochemistry and Western blot. qRT-PCR was performed to detect the mRNA expression of JNK, Bcl-2, Beclin-1, and LC3. The general conditions of mice in model and low-dose acteoside groups were poor, while the general conditions of mice in the remaining three groups were improved. The body weight of mice in medium-dose acteoside group, high-dose acteoside group, and cisplatin group was smaller than that in model group(P<0.01). The tumor volume in model group was insignificantly different from that in low-dose acteoside group, and the volume in cisplatin group showed no significant difference from that in high-dose acteoside group. Tumor volume and weight in medium-dose and high-dose acteoside groups and cisplatin group were lower than those in the model group(P<0.001). The tumor-inhibiting rates were 10.72%, 40.32%, 53.79%, and 56.44% in the low-dose, medium-dose, and high-dose acteoside groups and cisplatin group, respectively. HE staining showed gradual decrease in the count of hepatoma cells and increasing sign of cell necrosis in the acteoside and cisplatin groups, and the necrosis was particularly obvious in the high-dose acteoside group and cisplatin group. Immunohistochemical results suggested that the expression of Beclin-1, LC3, p-JNK, and JNK was up-regulated in acteoside and cisplatin groups(P<0.05). The results of immunohistochemistry, Western blot, and qRT-PCR indicated that the expression of Bcl-2 was down-regulated in the medium-dose and high-dose acteoside groups and cisplatin group(P<0.01). Western blot showed that the expression of Beclin-1, LC3, and p-JNK was up-regulated in acteoside and cisplatin groups(P<0.01), and there was no difference in the expression of JNK among groups. qRT-PCR results showed that the levels of Beclin-1 and LC3 mRNA were up-regulated in the acteoside and cisplatin groups(P<0.05), and the level of JNK mRNA was up-regulated in medium-dose and high-dose acteoside groups and cisplatin group(P<0.001). Acteoside promotes apoptosis and autophagy of H22 cells in mice hepatoma cells by up-regulating the JNK signaling pathway, thus inhibiting tumor growth.

Neotuberostemonine and tuberostemonine ameliorate pulmonary fibrosis through suppressing TGF-β and SDF-1 secreted by macrophages and fibroblasts via the PI3K-dependent AKT and ERK pathways / 中国天然药物

Activated fibroblasts and M2-polarized macrophages may contribute to the progression of pulmonary fibrosis by forming a positive feedback loop. This study was aimed to investigate whether fibroblasts and macrophages form this loop by secreting SDF-1 and TGF-β and the impacts of neotuberostemonine (NTS) and tuberostemonine (TS). Mice were intratracheally injected with 3 U·kg-1 bleomycin and orally administered with 30 mg·kg-1 NTS or TS. Primary pulmonary fibroblasts (PFBs) and MH-S cells (alveolar macrophages) were used in vitro. The animal experiments showed that NTS and TS improved fibrosis related indicators, inhibited fibroblast activation and macrophage M2 polarization, and reduced the levels of TGF-β and SDF-1 in alveolar lavage fluid. Cell experiments showed that TGF-β1 may activated fibroblasts into myofibroblasts secreting SDF-1 by activating the PI3K/AKT/HIF-1α and PI3K/PAK/RAF/ERK/HIF-1α pathways. It was also found for the first time that SDF-1 was able to directly polarize macrophages into M2 phenotype secreting TGF-β through the same pathways as mentioned above. Moreover, the results of the cell coculture confirmed that fibroblasts and macrophages actually developed a feedback loop to promote fibrosis, and the secretion of TGF-β and SDF-1 was crucial for maintaining this loop. NTS and TS may disturb this loop through inhibiting both the PI3K/AKT/HIF-1α and PI3K/PAK/RAF/ERK/HIF-1α pathways to improve pulmonary fibrosis. NTS and TS are stereoisomeric alkaloids with pyrrole[1,2-a]azapine skeleton, and their effect on improving pulmonary fibrosis may be largely attributed to their parent nucleus. Moreover, this study found that inhibition of both the AKT and ERK pathways is essential for maximizing the improvement of pulmonary fibrosis.

Resveratrol improves cognitive function in severely burned rats by inhibiting hippocampal NF-κB/JNK pathway / 细胞与分子免疫学杂志

Objective To investigate the protective effect of resveratrol (RSV) on improving cognitive function in severely burned rats and its possible mechanism. Methods 18 male SD rats aged 18-20 months were randomly divided into 3 groups: control group, model group and RSV group, with 6 rats in each group. After successful modeling, the rats in RSV group were gavaged once daily with RSV (20 mg/kg). Meanwhile, the rats in control group and model group were gavaged once daily with an equal volume of sodium chloride solution. After 4 weeks, the cognitive function of all rats was estimated by Step-down Test. The concentration of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) protein in serum of rats were detected by ELISA. The expression of IL-6, TNF-α mRNA and protein were estimated by real-time PCR and Western blotting. The apoptosis of hippocampal neurons was tested by terminal deoxynuclectidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL). The expression of nuclear transcription factor-κB (NF-κB)/c-Jun N-terminal kinase (JNK) pathway-related proteins in hippocampus were assessed by Western blotting. Results Compared with the rats in model group, rats in RSV group exhibited improved cognitive function. Consistently, the rats in RSV group had a reduced concentration of TNF-α and IL-6 in serum, decreased mRNA and protein expressions of TNF-α and IL-6 in hippocampus, and decreased apoptosis rate and relative expression of p-NF-κB p65/NF-κB p65 and p-JNK/JNK in hippocampal neurons. Conclusion RSV alleviates inflammatory response and hippocampal neuronal apoptosis by inhibiting NF-κB/JNK pathway, thereby improving cognitive function in severely burned rats.

Methylene blue reduces IL-1β levels by enhancing ERK1/2 and AKT phosphorylation to improve diabetic retinopathy in rats / 细胞与分子免疫学杂志

Objective To investigate the neuroprotective effect of methylene blue on diabetic retinopathy in rats. Methods Thirty SD rats were randomly divided into blank, control and experimental groups. The control and experimental groups were induced with diabetes by streptozotocin (STZ) intraperitoneal injection. After 6 weeks of successful modeling, the experimental group received intravitreal injection of methylene blue at a dose of [0.2 mg/(kg.d)], while the control group received an equal amount of dimethyl sulfoxide (DMSO) intravitreal injection, both continuously injected for 7 days. ELISA was used to detect the levels of retinal superoxide dismutase (SOD), 8-iso-prostaglandin F2alpha (iPF2α) and interleukin-1β (IL-1β) in rats. Western blot analysis was used to detect the expression of retinal extracellular signal-regulated kinase 1/2 phosphorylation (p-ERK1/2) and phosphorylated protein kinase B (p-AKT), and PAS staining was used to detect retinal morphological changes. Results Compared with the blank group rats, the retinal SOD activity in the control and experimental group rats was significantly reduced. iPF2α, IL-1β and p-ERK1/2 level increased, while p-AKT level decreased. Compared with the control group, the SOD activity of the experimental group rats increased. iPF2α and IL-1β level went down, while p-ERK1/2 and p-AKT level went up significantly. The overall thickness of the retinal layer and the number of retinal ganglion cells were significantly reduced. Conclusion Methylene blue improves diabetic retinopathy in rats by reducing retinal oxidative stress and enhancing ERK1/2 and AKT phosphorylation.

Analysis of the effect of midazolam on pain in a rat model of lumbar disc herniation based on the p38 MAPK signaling pathway / 中国骨伤

OBJECTIVE@#To investigate the effect of midazolam on pain in lumbar disc herniation model rats based on p38 MAPK signaling pathway.@*METHODS@#Fifty SPF-grade Sprague-Dawley healthy rats, half male and half female, were selected and randomly divided into normal group, model group, and low-dose, medium-dose, high-dose groups. Model group and low-dose, medium-dose, high-dose groups were initially modeled for lumbar disc herniation. Intraperitoneal injection of saline was performed in rats of normal and model groups; and in the low-dose, medium-dose, and high-dose groups, intraperitoneal injection of midazolam was performed with doses of 30, 60, and 90 mg/kg, respectively. Interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), 5-hydroxytryptamine (5-HT), β-endorphin (β-EP), substance P (SP), neuropeptide Y (NPY) were detected in the serum of rats by enzyme-linked immunoassay. The expression of p38 MAPK and matrix metalloproteinase-3(MMP-3) protein were detected by Western blot in the tissues of rats of each group.@*RESULTS@#The levels of TNF-α, IL-1β and β-EP were higher and the level of 5-HT was lower in the model group than in the normal group(P<0.05);the levels of TNF-α, IL-1β and β-EP were lower and the level of 5-HT was higher in the low-dose, medium-dose and high-dose groups than in the model group(P<0.05). The levels of SP and NPY increased in the model group compared with the normal group (P<0.05) and the levels of SP and NPY decreased in the low-dose, medium-dose and high-dose groups compared with the model group (P<0.05). The expression of p38 MAPK and MMP-3 increased in the model group compared with the normal group (P<0.05); the expression of p38 MAPK and MMP-3 decreased in the low-dose, medium-dose and high-dose compared with the model group(P<0.05).@*CONCLUSION@#Midazolam may ameliorate the immune inflammatory response in rats with a model of lumbar disc herniation, possibly regulated through the p38MAPK signaling pathway.

Exploring the treatment of sepsis-associated acute lung injury with Liangge Powder via ERK1/2 and PI3K/AKT pathways: based on network pharmacology and whole animal experimentation / 中华劳动卫生职业病杂志

Objective: To investigate the therapeutic effect and mechanism of Liangge Powder against sepsis-induced acute lung injury (ALI) . Methods: From April to December 2021, the key components of Liangge Powder and its targets against sepsis-induced ALI were analyzed by network pharmacology, and to enrich for relevant signaling pathways. A total of 90 male Sprague-Dawley rats were randomly assigned to sham-operated group, sepsis-induced ALI model group (model group), Liangge Powder low, medium and high dose group, ten rats in the sham-operated group and 20 rats in each of the remaining four groups. Sepsis-induced ALI model was established by cecal ligation and puncture. Sham-operated group: gavage with 2 ml saline and no surgical treatment. Model group: surgery was performed and 2 ml saline was gavaged. Liangge Powder low, medium and high dose groups: surgery and gavage of Liangge Powder 3.9, 7.8 and 15.6 g/kg, respectively. To measure the wet/dry mass ratio of rats lung tissue and evaluate the permeability of alveolar capillary barrier. Lung tissue were stained with hematoxylin and eosin for histomorphological analysis. The levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL) -6 and IL-1β in bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay. The relative protein expression levels of p-phosphatidylinositol 3-kinase (PI3K), p-protein kinase B (AKT), and p-ertracellular regulated protein kinases (ERK) were detected via Western blot analysis. Results: Network pharmacology analysis indicated that 177 active compounds of Liangge Powder were selected. A total of 88 potential targets of Liangge Powder on sepsis-induced ALI were identified. 354 GO terms of Liangge Powder on sepsis-induced ALI and 108 pathways were identified using GO and KEGG analysis. PI3K/AKT signaling pathway was recognized to play an important role for Liangge Powder against sepsis-induced ALI. Compared with the sham-operated group, the lung tissue wet/dry weight ratio of rats in the model group (6.35±0.95) was increased (P<0.001). HE staining showed the destruction of normal structure of lung tissue. The levels of IL-6 [ (392.36±66.83) pg/ml], IL-1β [ (137.11±26.83) pg/ml] and TNF-α [ (238.34±59.36) pg/ml] were increased in the BALF (P<0.001, =0.001, <0.001), and the expression levels of p-PI3K, p-AKT and p-ERK1/2 proteins (1.04±0.15, 0.51±0.04, 2.31±0.41) were increased in lung tissue (P=0.002, 0.003, 0.005). The lung histopathological changes were reduced in each dose group of Liangge Powder compared with the model group. Compared with the model group, the wet/dry weight ratio of lung tissue (4.29±1.26) was reduced in the Liangge Powder medium dose group (P=0.019). TNF-α level [ (147.85±39.05) pg/ml] was reduced (P=0.022), and the relative protein expression levels of p-PI3K (0.37±0.18) and p-ERK1/2 (1.36±0.07) were reduced (P=0.008, 0.017). The wet/dry weight ratio of lung tissue (4.16±0.66) was reduced in the high-dose group (P=0.003). Levels of IL-6, IL-1β and TNF-α[ (187.98±53.28) pg/ml, (92.45±25.39) pg/ml, (129.77±55.94) pg/ml] were reduced (P=0.001, 0.027, 0.018), and relative protein expression levels of p-PI3K, p-AKT and p-ERK1/2 (0.65±0.05, 0.31±0.08, 1.30±0.12) were reduced (P=0.013, 0.018, 0.015) . Conclusion: Liangge Powder has therapeutic effects in rats with sepsis-induced ALI, and the mechanism may be related to the inhibition of ERK1/2 and PI3K/AKT pathway activation in lung tissue.

Cyasterone inhibits IL-1β-mediated apoptosis and inflammation via the NF-κB and MAPK signaling pathways in rat chondrocytes and ameliorates osteoarthritisin vivo / 中国天然药物

Osteoarthritis is a prevalent global joint disease, which is characterized by inflammatory reaction and cartilage degradation. Cyasterone, a sterone derived from the roots of Cyathula officinalis Kuan, exerts protective effect against several inflammation-related diseases. However, its effect on osteoarthritis remains unclear. The current study was designed to investigate the potential anti-osteoarthritis activity of cyasterone. Primary chondrocytes isolated from rats induced by interleukin (IL)-1β and a rat model stimulated by monosodium iodoacetate (MIA) were used for in vitro and in vivo experiments, respectively. The results of in vitro experiments showed that cyasterone apparently counteracted chondrocyte apoptosis, increased the expression of collagen II and aggrecan, and restrained the production of the inflammatory factors inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5), metalloproteinase-3 (MMP-3), and metalloproteinase-13 (MMP-13) induced by IL-1β in chondrocytes. Furthermore, cyasterone ameliorated the inflammation and degenerative progression of osteoarthritis potentially by regulating the nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. For in vivo experiments, cyasterone significantly alleviated the inflammatory response and cartilage destruction of rats induced by monosodium iodoacetate, where dexamethasone was used as the positive control. Overall, this study laid a theoretical foundation for developing cyasterone as an effective agent for the alleviation of osteoarthritis.

Bavachin induces apoptosis in colorectal cancer cells through Gadd45a via the MAPK signaling pathway / 中国天然药物

Bavachin is a dihydroflavonoid compound isolated from Psoralea corylifolia, and exhibits anti-bacterial, anti-inflammatory, anti-tumor and lipid-lowering activities. Recent attention has gradually drawn on bavachin-induced apoptosis in many human cancer cell lines. However, the anti-cancer effects and related mechanisms in colorectal cancer remain unknown. Here, we investigated the effects of bavachin on colorectal cancer in vivo and in vitro. The results showed that bavachin inhibited the proliferation of human colorectal cancer cells and induce apoptosis. These changes were mediated by activating the MAPK signaling pathway, which significantly up-regulated the expression of Gadd45a. Furthermore, Gadd45a silencing obviously attenuated bavachin-mediated cell apoptosis. Inhibition of the MAPK signaling pathway by JNK/ERK/p38 inhibitors also weakened the up-regulation of Gadd45a by bavachin. The anticancer effect of bavachin was also validated using a mouse xenograft model of human colorectal cancer. In conclusion, these findings suggest that bavachin induces the apoptosis of colorectal cancer cells through activating the MAPK signaling pathway.

Type III secretory protein SINC of Chlamydia psittaci promotes host cell autophagy by activating the MAPK/ERK signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effects of SINC, a secreted protein of Chlamydia psittaci, on autophagy of host cells and the role of MAPK/ERK signaling pathway in mediating SINC-induced autophagy.@*METHODS@#RAW 264.7 cells treated with recombinant SINC were examined for changes in expression levels of LC3-II, Beclin-1, phosphorylated and total ERK1/2 using Western blotting. The expression level of LC3 in the treated cells was detected using immunofluorescence analysis, and the formation of autophagosomes and autolysosomes was observed with transmission electron microscopy (TEM). The effect of pretreatment with U0126 (a specific ERK inhibitor) on the expression levels of LC3-II and Beclin-1 in RAW 264.7 cells exposed to different concentrations of SINC was examined using Western blotting, and LC3 puncta in the cells was detected with immunofluorescence analysis.@*RESULTS@#The expression levels of LC3-II and Beclin-1 were the highest in RAW 264.7 cells treated with 2 μg/mL SINC for 12h. Immunofluorescence analysis showed exposure to SINC significantly increased the number of cells containing LC3 puncta, where the presence of autophagosomes and autolysosomes was detected. Exposure to 2 μg/mL SINC for 15 min resulted in the most significant increase of the ratios of p-ERK1/2/ERK1/2 in RAW 264.7 cells. Pretreatment of the cells with U0126 prior to SINC exposure significantly decreased the ratio of p-ERK1/2/ERK1/2, lowered the expression levels of LC3-II and Beclin-1, and decreased LC3 aggregation in the cells.@*CONCLUSIONS@#SINC exposure can induce autophagy in RAW 264.7 cells by activating the MAPK/ERK signaling pathway.

Low-dose paclitaxel modulates the cross talk between the JNK and Smad signaling in primary biliary fibroblasts

SUMMARY OBJECTIVE: The objective of this study was to explore the molecular mechanism underlying the occurrence of benign bile duct stricture and the target of low-dose paclitaxel in the prevention of benign bile duct stricture. METHODS: Under the stimulation of transforming growth factor beta 1, the expression of collagen type I and connective tissue growth factor were detected on isolated primary fibroblasts. The phosphorylation levels of JNK and Smad2L were detected using Western blot. The effect of low-dose paclitaxel on the transforming growth factor beta 1-induced inhibition of type I collagen and connective tissue growth factor expression and JNK and Smad2L phosphorylation was also observed. RESULTS: Transforming growth factor beta 1 induced the secretion of type I collagen and connective tissue growth factor as well as JNK phosphorylation in biliary fibroblasts. The JNK inhibitor or siRNA-Smad2 inhibited the transforming growth factor beta 1-induced secretion of type I collagen and connective tissue growth factor. Low-dose paclitaxel inhibited the expression of type I collagen induced by transforming growth factor beta 1 and may inhibit the secretion of collagen in biliary fibroblasts. CONCLUSION: The activation of JNK/Smad2L induced by transforming growth factor beta 1 is involved in the occurrence of benign bile duct stricture that is mediated by the overexpression of type I collagen and connective tissue growth factor, and low-dose paclitaxel may inhibit the phosphorylation of JNK/Smad2L.

Research advances in the role of MAPK cascade in regulation of cell growth, immunity, inflammation, and cancer / 中南大学学报(医学版)

Mitogen-activated protein kinase (MAPK) cascade system is one of the highly conserved signal systems in eukaryotic cells, which participates in the regulation of many biological processes. Under the stimulation of different signals (such as cytokines, neurotransmitters, and hormones), MAPK cascade activates downstream targets and controls a variety of cellular processes, including growth, immunity, inflammation, and stress response. In different cells, the effects of MAPK cascade on cells vary with the stimuli and the duration of stimulation. MAPK cascade induces Th differentiation and participates in T cell receptor signal pathway and B cell receptor signal pathway. MAPK cascades regulate various cellular activities related to the occurrence and development of cancer. A thorough and systematic understanding of the specific regulatory effects of MAPK cascade on various cellular processes will provide theoretical guidance for treating various diseases.

Betahistine alleviates benign paroxysmal positional vertigo (BPPV) through inducing production of multiple CTRP family members and activating the ERK1/2-AKT/PPARy pathway

BACKGROUND: Betahistine is a clinical medication for the treatment of benign paroxysmal positional vertigo (BPPV). Otolin, a secreted glycoprotein with a C-terminal globular domain homologous to the immune complement C1q, has been identified as a biomarker for BPPV. However, the role of complement C1q/TNF-related proteins (CTRPs) with a C-terminal globular domain in BPPV is unclear, so we explored the change of CTRPs in betahistine treated BPPV. METHODS: We treated BPPV patients with Betahistine (12 mg/time, 3 times/day) for 4 weeks and observed the clinical efficacy and the expression of CTRP family members in BPPV patients. Then, we constructed a vertigo mice model of vestibular dysfunction with gentamicin (150 mg/Kg) and a BPPV model of Slc26a4loop/loop mutant mice. Adenoviral vectors for CTRP expression vector and small interfering RNA were injected via the intratympanic injection into mice and detected the expression of CTRP family members, phosphorylation levels of ERK and AKT and the expression of PPARγ. In addition, we treated mice of vestibular dysfunction with Betahistine (10 mg/Kg) and/or ERK inhibitor of SCH772984 (12 mg/Kg) and/or and PPARγ antagonist GW9662 (1 mg/Kg) for 15 days, and evaluated the accuracy of air righting reflex, the time of contact righting reflex and the scores of head tilt and swimming behavior. RESULTS: After treatment with Betahistine, the residual dizziness duration and the score of the evaluation were reduced, and the expression of CTRP1, 3, 6, 9 and 12 were significantly increased in BPPV patients. We also found that Betahistine improved the accuracy of air righting reflex, reduced the time of contact righting reflex and the scores of head tilt and swimming behavior in gentamicin-treated mice and Slc26a4loop/loop mutant mice. The expression levels of CTRP1, 3, 6, 9 and 12, phosphorylation levels of ERK and AKT, and PPARγ expression were significantly increased, and the scores of head tilt and swimming behavior were decreased in vestibular dysfunction mice with overexpression of CTRPs. Silencing CTRPs has the opposite effect. SCH772984 reversed the effect of Betahistine in mice with vestibular dysfunction. CONCLUSION: Betahistine alleviates BPPV through inducing production of multiple CTRP family members and activating the ERK1/2-AKT/PPARy pathway.

Electroacupuncture Attenuated Phenotype Transformation of Vascular Smooth Muscle Cells via PI3K/Akt and MAPK Signaling Pathways in Spontaneous Hypertensive Rats / 中国结合医学杂志

OBJECTIVE@#To investigate whether the antihypertensive mechanism of electroacupuncture (EA) is associated with attenuating phenotype transformation of vascular smooth muscle cells (VSMCs) via phosphoinositide3-kinase (PI3K)/protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) signaling pathways.@*METHODS@#Eight Wistar-ktoyo (WKY) rats were set as normal blood pressure group (normal group). A total of 32 spontaneous hypertensive rats (SHRs) were randomly divided into 4 groups using random number tables: a model group, an EA group, an EA+PI3K antagonist group (EA+P group), and an EA+p38 MAPK agonist+extracellular signal-regulated kinase (ERK) agonist group (EA+M group) (n=8/group). SHRs in EA group, EA+P group and EA+M group received EA treatment 5 sessions per week for continuous 4 weeks, while rats in the normal and model groups were bundled in same condition. The systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) of each rat was measured at 0 week and the 4th week. After 4-week intervention, thoracic aorta was collected for hematoxylin-eosin (HE) staining, immunohistochemistry [the contractile markers α-smooth muscle actin (α-SMA) and calponin and the synthetic marker osteopontin (OPN)] and Western blot [α-SMA, calponin, OPN, PI3K, phosphorylated-Akt (p-Akt), Akt, p-p42/44 ERK, total p42/44 ERK, p-p38 MAPK and total p38 MAPK].@*RESULTS@#EA significantly reduced SBP, DBP and MAP (P<0.01). HE staining showed that the wall thickness of thoracic aorta in EA group was significantly decreased (P<0.01). From results of immunohistochemistry and Western blot, EA increased the expression of α-SMA and calponin, and decreased the expression of OPN (P<0.01). In addition, the expression of PI3K and p-Akt increased (P<0.01), while the expression of p-p42/44 ERK and p-p38 MAPK decreased in EA group (P<0.01). However, these effects were reversed by PI3K antagonist, p38 MAPK agonist and ERK agonist.@*CONCLUSIONS@#EA was an effective treatment for BP management. The antihypertensive effect of EA may be related with inhibition of phenotypic transformation of VSMCs, in which the activation of PI3K/Akt and the repression of MAPK pathway were involved.

Effect of Jingfang Granules on carrageenan-induced tail thrombosis in mice based on ERK/p38 MAPK signaling pathway / 中国中药杂志

The present study explored the anti-inflammatory and anti-thrombotic mechanism of Jingfang Granules on tail thrombosis induced by carrageenan in mice. Thirty-two male ICR mice were randomly divided into a control group, a model group, a Jingfang Granules group, and a positive drug(aspirin) group, with eight mice in each group. The thrombosis model was induced by intraperitoneal injection of carrageenan(45 mg·kg~(-1)) combined with low-temperature stimulation, and the mice were treated with drugs for 7 days before modeling. Twenty-four hours after modeling, blood was detected for four blood coagulation indices in each group. The enzyme-linked immunosorbent assay(ELISA) was used to detect the activity of plasma interleukin-6(IL-6), interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and other inflammatory factors. The tails of mice in each group were cut off to observe tail lesions and measure the length of the thrombus. The protein expression and phosphorylation level of extracellular signal-regulated kinase 1/2(ERK1/2) and p38 mitogen-activated protein kinase(p38 MAPK) in spleen tissues were detected by Western blot. The results showed that dark red thrombus appeared in the tails of mice in each group. The length of the black part accounted for about 40% of the total tail in the model group. Additionally, the model group showed prolonged prothrombin time(PT), increased fibrinogen(FIB) content, and shortened activated partial thromboplastin time(APTT). Compared with the model group, the groups with drug intervention displayed shortened black parts in the tail and improved four blood coagulation indices(P<0.05). As revealed by ELISA, the expression levels of TNF-α, IL-1β, and IL-6 in the mouse plasma were significantly up-regulated in the model group, and those in the groups with drug intervention were reduced as compared with the model group(P<0.05). As demonstrated by Western blot, the protein expression and phosphorylation levels of ERK1/2 and p38 MAPK in the spleen tissues were significantly elevated in the model group, while those in the Jingfang Granules group were down-regulated as compared with the model group with a significant difference. Jingfang Granules can inhibit tail thrombosis of mice caused by carrageenan presumedly by inhibiting the activation of ERK1/2 and p38 MAPK signaling pathways.

Melittin suppresses growth and induces apoptosis of non-small-cell lung cancer cells via down-regulation of TGF-ß-mediated ERK signal pathway

The purpose of this study was to investigate the anti-cancer effect of melittin on growth, migration, invasion, and apoptosis of non-small-cell lung cancer (NSCLC) cells. This study also explored the potential anti-cancer mechanism of melittin in NSCLC cells. The results demonstrated that melittin suppressed growth, migration, and invasion, and induced apoptosis of NSCLC cells in vitro. Melittin increased pro-apoptotic caspase-3 and Apaf-1 gene expression. Melittin inhibited tumor growth factor (TGF)-β expression and phosphorylated ERK/total ERK (pERK/tERK) in NSCLC cells. However, TGF-β overexpression (pTGF-β) abolished melittin-decreased TGF-β expression and pERK/tERK in NSCLC cells. Treatment with melittin suppressed tumor growth and prolonged mouse survival during the 120-day observation in vivo. Treatment with melittin increased TUNEL-positive cells and decreased expression levels of TGF-β and ERK in tumor tissue compared to the control group. In conclusion, the findings of this study indicated that melittin inhibited growth, migration, and invasion, and induced apoptosis of NSCLC cells through down-regulation of TGF-β-mediated ERK signaling pathway, suggesting melittin may be a promising anti-cancer agent for NSCLC therapy.

Oxidized low-density lipoprotein stimulates dendritic cells maturation via LOX-1-mediated MAPK/NF-κB pathway

Dendritic cells (DCs) play a crucial role as central orchestrators of immune system response in atherosclerosis initiation and progression. Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is involved in the immune maturation of DCs, but the underlying mechanisms remain unclear. We isolated mouse bone marrow progenitors and stimulated them with granulocyte-macrophage colony-stimulating factor and interleukin (IL)-4 to induce immature DCs. We then treated DCs with oxidized low-density lipoprotein (oxLDL) to induce maturation. LOX-1 siRNA was used to investigate the modulation of LOX-1 on the development of DCs and the underlying signal pathways. CD11c-positive DCs were successfully derived from mouse bone marrow progenitors. OxLDL promoted the expressions of DCs maturation markers and pro-inflammatory cytokines. OxLDL also upregulated LOX-1 expression and activated MAPK/NF-κB pathways. LOX-1 siRNA could attenuate the expression of MAPK/NF-κB pathways and inflammatory cytokines. In conclusion, oxLDL induced the maturation of DCs via LOX-1-mediated MAPK/NF-κB pathway, which contributed to the initiation and progression of atherosclerosis.

Manuka honey enhanced sensitivity of HepG2, hepatocellular carcinoma cells, for Doxorubicin and induced apoptosis through inhibition of Wnt/ß-catenin and ERK1/2

BACKGROUND: Recently, there is increasing awareness focused on the identification of naturally occurring anticancer agents derived from natural products. Manuka honey (MH) has been recognized for its biological properties as antimicrobial, antioxidant, and anticancer properties. However, its antiproliferative mechanism in hepatocellular carcinoma is not investigated. The current study focused mainly on investigating the molecular mechanism and synergistic effect of anticancer properties of MH on Doxorubicin (DOX)-mediated apoptotic cell death, using two different p53 statuses (HepG2 and Hep3B) and one non-tumorigenic immortalized liver cell line. RESULTS: MH treatment showed a proliferative inhibitory effect on tested cells in a dose-dependent manner with IC50 concentration of (6.92 ± 0.005%) and (18.62 ± 0.07%) for HepG2 and Hep3B cells, respectively, and induced dramatic morphological changes of Hep-G2 cells, which considered as characteristics feature of apoptosis induction after 48 h of treatment. Our results showed that MH or combined treatments induced higher cytotoxicity in p53-wild type, HepG2, than in p53-null, Hep3B, cells. Cytotoxicity was not observed in normal liver cells. Furthermore, the synergistic effect of MH and Dox on apoptosis was evidenced by increased annexin-V-positive cells and Sub-G1 cells in both tested cell lines with a significant increase in the percentage of Hep-G2 cells at late apoptosis as confirmed by the flow cytometric analysis. Consistently, the proteolytic activities of caspase-3 and the degradation of poly (ADP-ribose) polymerase were also higher in the combined treatment which in turn accompanied by significant inhibitory effects of pERK1/2, mTOR, S6K, oncogenic ß-catenin, and cyclin D1 after 48 h. In contrast, the MH or combined treatment-induced apoptosis was accompanied by significantly upregulated expression of proapoptotic Bax protein and down-regulated expression of anti-apoptotic Bcl-2 protein after 48 h. CONCLUSIONS: Our data showed a synergistic inhibitory effect of MH on DOX-mediated apoptotic cell death in HCC cells. To our knowledge, the present study provides the first report on the anticancer activity of MH and its combined treatment with DOX on HCC cell lines, introducing MH as a promising natural and nontoxic anticancer compound.