Loss of monopolar spindle-binding protein 3B expression promotes colorectal cancer malignant behaviors by activation of target of rapamycin kinase/autophagy signaling

BACKGROUND Monopolar spindle-binding protein 3B(MOB3B)functions as a signal transducer and altered MOB3B expression is associated with the development of human cancers.AIM To investigate the role of MOB3B in colorectal cancer(CRC).METHODS This study collected 102 CRC tissue samples for immunohistochemical detection of MOB3B expression for association with CRC prognosis.After overexpression and knockdown of MOB3B expression were induced in CRC cell lines,changes in cell viability,migration,invasion,and gene expression were assayed.Tumor cell autophagy was detected using transmission electron microscopy,while nude mouse xenograft experiments were performed to confirm the in-vitro results.RESULTS MOB3B expression was reduced in CRC vs normal tissues and loss of MOB3B expression was associated with poor CRC prognosis.Overexpression of MOB3B protein in vitro attenuated the cell viability as well as the migration and invasion capacities of CRC cells,whereas knockdown of MOB3B expression had the opposite effects in CRC cells.At the molecular level,microtubule-associated protein light chain 3 II/I expression was elevated,whereas the expression of matrix metalloproteinase(MMP)2,MMP9,sequestosome 1,and phosphorylated mechanistic target of rapamycin kinase(mTOR)was downregulated in MOB3B-overexpressing RKO cells.In contrast,the opposite results were observed in tumor cells with MOB3B knockdown.The nude mouse data confirmed these in-vitro findings,i.e.,MOB3B expression suppressed CRC cell xenograft growth,whereas knockdown of MOB3B expression promoted the growth of CRC cell xenografts.CONCLUSION Loss of MOB3B expression promotes CRC development and malignant behaviors,suggesting a potential tumor suppressive role of MOB3B in CRC by inhibition of mTOR/autophagy signaling.

Suppressing high mobility group box-1 release alleviates morphine tolerance via the adenosine5'-monophosphate-activated protein kinase/heme oxygenase-1 pathway

Opioids,such as morphine,are the most potent drugs used to treat pain.Long-term use results in high tolerance to morphine.High mobility group box-1(HMGB1) has been shown to participate in neuropathic or inflammatory pain,but its role in morphine tolerance is unclear.In this study,we established rat and mouse models of morphine tolerance by intrathecal injection of morphine for 7 consecutive days.We found that morphine induced rat spinal cord neurons to release a large amount of HMGB1.HMGB1 regulated nuclear factor κB p65 phosphorylation and interleukin-1β production by increasing Toll-like receptor 4receptor expression in microglia,thereby inducing morphine tolerance.Glycyrrhizin,an HMGB1 inhibito r,markedly attenuated chronic morphine tole rance in the mouse model.Finally,compound C(adenosine 5’-monophosphate-activated protein kinase inhibitor) and zinc protoporphyrin(heme oxygenase-1 inhibitor)alleviated the morphine-induced release of HMGB1 and reduced nuclear factor κB p65 phosphorylation and interleukin-1β production in a mouse model of morphine tolerance and an SH-SY5Y cell model of morphine tole rance,and alleviated morphine tolerance in the mouse model.These findings suggest that morphine induces HMGB1 release via the adenosine 5’-monophosphate-activated protein kinase/heme oxygenase-1 signaling pathway,and that inhibiting this signaling pathway can effectively reduce morphine tole rance.

Osteopontin promotes gastric cancer progression via phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway

BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors.Osteopontin(OPN)is thought to be closely related to the occurrence,metastasis and prognosis of many types of tumors.AIM To investigate the effects of OPN on the proliferation,invasion and migration of GC cells and its possible mechanism.METHODS The mRNA and protein expression of OPN in the GC cells were analyzed by realtime quantitative-reverse transcription polymerase chain reaction and western blotting,and observe the effect of varying degree expression OPN on the proliferation and other behaviors of GC.Next,the effects of OPN knockdown on GC cells migration and invasion were examined.The short hairpin RNA(shRNA)and negative control shRNA targeting OPN-shRNA were transfected into the cells according to the manufacturer’s instructions.Non transfected cells were classified as control in the identical transfecting process.24 h after RNA transfection cell proliferation activity was detected by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay,and cell invasiveness and migration were detected by Trans well assay.Meanwhile,the expression of protein kinase B(AKT),matrix metalloproteinase 2(MMP-2)and vascular endothelial growth factor(VEGF)in the human GC cell lines was detected by reverse transcription polymerase chain reaction and western blotting.RESULTS The results of this study revealed that OPN mRNA and protein expression levels were highly expressed in SGC-7901 cells.OPN knockdown by specific shRNA noticeably reduced the capabilities of proliferation,invasion and migration of SGC-7901 cells.Moreover,in the experiments of investigating the underlying mechanism,results showed that OPN knockdown could down-regulated the expression of MMP-2 and VEGF,it also decreased the phosphorylation of AKT.Meanwhile,the protein expression levels of MMP-2,VEGF and phosphorylated AKT was noticeable lower than that in control group in the GC cells after they were added to phosphatidylinositol-3-kinase(PI3K)inhibitor(LY294002).CONCLUSION These results suggested that OPN though PI3K/AKT/mammalian target of rapamycin signal pathway to upregulate MMP-2 and VEGF expression,which contribute SGC-7901 cells to proliferation,invasion and migration.Thus,our results demonstrate that OPN may serve as a novel prognostic biomarkers as well as a potential therapeutic targets for GC.

基于PI3K/PKB信号通路变化探究清胰汤在急性胰腺炎相关性肺损伤治疗中的应用价值及作用机制

目的:基于磷脂酰肌醇3羟激酶(PI3K)/磷酸化蛋白激酶B(PKB)信号通路变化探究清胰汤在急性胰腺炎相关性肺损伤治疗中的应用价值及作用机制。方法:选取2020年8月~2022年11月我院收治的98例急性胰腺炎相关性肺损伤患者,随机分为对照组与观察组各49例,对照组给予常规西药治疗,观察组在对照组基础上加用中药清胰汤治疗,均治疗2周,比较两组患者的临床疗效,肠胃恢复状况(发热、腹胀腹痛、恶心呕吐及肠鸣音恢复时间),血氧指标[血氧分压(PaO_(2))、氧合指数(OI)水平],血清学指标[淀粉酶(AMY)、脂肪酶(LPS)、PI3K、PKB水平],生活质量[生活质量核心问卷(QLQ-C30)评分]以及不良反应发生情况。结果:治疗后,观察组患者的总有效率为91.84%高于对照组的73.47%(P<0.05);观察组患者恶心呕吐、腹胀腹痛、发热、肠鸣音等肠胃状况恢复时间均短于对照组(P<0.05);观察组患者的PaO_(2)、OI水平均高于对照组(P<0.05);观察组患者的血清AMY、LPS、PI3K、PKB水平均低于对照组(P<0.05);观察组患者的QLQ-C30评分低于对照组(P<0.05);两组患者均未见有明显严重不良反应发生,且两组间不良反应发生率比较无统计学差异(P>0.05)。结论:清胰汤对急性胰腺炎相关性肺损伤有较好的临床治疗效果,可有效缓解患者症状,提高生活质量,用药安全性好,PI3K/PKB信号通路激活被抑制是其主要作用机制之一。

Yinchenhao decoction attenuates obstructive jaundice-induced liver injury and hepatocyte apoptosis by suppressing protein kinase RNA-like endoplasmic reticulum kinase-induced pathway

BACKGROUND Chronic biliary obstruction results in ischemia and hypoxia of hepatocytes,and leads to apoptosis.Apoptosis is very important in regulating the homeostasis of the hepatobiliary system.Endoplasmic reticulum(ER)stress is one of the signaling pathways that induce apoptosis.Moreover,the protein kinase RNA-like endoplasmic reticulum kinase(PERK)-induced apoptotic pathway is the main way;but its role in liver injury remains unclear.Yinchenhao decoction(YCHD)is a traditional Chinese medicine formula that alleviates liver injury and apoptosis,yet its mechanism is unknown.We undertook this study to investigate the effects of YCHD on the expression of ER stress proteins and hepatocyte apoptosis in rats with obstructive jaundice(OJ).AIM To investigate whether YCHD can attenuate OJ-induced liver injury and hepatocyte apoptosis by inhibiting the PERK-CCAAT/enhancer-binding protein homologous protein(CHOP)-growth arrest and DNA damage-inducible protein 34(GADD34)pathway and B cell lymphoma/leukemia-2 related X protein(Bax)/B cell lymphoma/leukemia-2(Bcl-2)ratio.METHODS For in vivo experiments,30 rats were divided into three groups:control group,OJ model group,and YCHD-treated group.Blood was collected to detect the indicators of liver function,and liver tissues were used for histological analysis.For in vitro experiments,30 rats were divided into three groups:G1,G2,and G3.The rats in group G1 had their bile duct exposed without ligation,the rats in group G2 underwent total bile duct ligation,and the rats in group G3 were given a gavage of YCHD.According to the serum pharmacology,serum was extracted and centrifuged from the rat blood to cultivate the BRL-3A cells.Terminal deoxynucleotidyl transferase mediated dUTP nick end-labelling(TUNEL)assay was used to detect BRL-3A hepatocyte apoptosis.Alanine aminotransferase(ALT)and aspartate transaminase(AST)levels in the medium were detected.Western blot and quantitative real-time polymerase chain reaction(qRT-PCR)analyses were used to detect protein and gene expression levels of PERK,CHOP,GADD34,Bax,and Bcl-2 in the liver tissues and BRL-3A cells.RESULTS Biochemical assays and haematoxylin and eosin staining suggested severe liver function injury and liver tissue structure damage in the OJ model group.The TUNEL assay showed that massive BRL-3A rat hepatocyte apoptosis was induced by OJ.Elevated ALT and AST levels in the medium also demonstrated that hepatocytes could be destroyed by OJ.Western blot or qRT-PCR analyses showed that the protein and mRNA expression levels of PERK,CHOP,and GADD34 were significantly increased both in the rat liver tissue and BRL-3A rat hepatocytes by OJ.The Bax and Bcl-2 levels were increased,and the Bax/Bcl-2 ratio was also increased.When YCHD was used,the PERK,CHOP,GADD34,and Bax levels quickly decreased,while the Bcl-2 levels increased,and the Bax/Bcl-2 ratio decreased.CONCLUSION OJ-induced liver injury and hepatocyte apoptosis are associated with the activation of the PERK-CHOP-GADD34 pathway and increased Bax/Bcl-2 ratio.YCHD can attenuate these changes.

Fenofibrate Pre-treatment Suppressed Inflammation by Activating Phosphoinositide 3 Kinase/Protein Kinase B(PI3K/Akt) Signaling in Renal Ischemia-Reperfusion Injury

The aim of this study was to investigate the possible beneficial effects of Fenofibrate on renal ischemia-reperfusion injury（IRI） in mice and its potential mechanism. IRI was induced by bilateral renal ischemia for 60 min followed by reperfusion for 24 h. Eighteen male C57BL/6 mice were randomly divided into three groups： sham-operated group（sham）, IRI＋saline group（IRI group）, IRI＋Fenofibrate（FEN） group. Normal saline or Fenofibrate（3 mg/kg） was intravenously injected 60 min before renal ischemia in IRI group and FEN group, respectively. Blood samples and renal tissues were collected at the end of reperfusion. The renal function, histopathologic changes, and the expression levels of pro-inflammatory cytokines [interleukin-8（IL-8）, tumor necrosis factor alpha（TNF-α） and IL-6] in serum and renal tissue homogenate were assessed. Moreover, the effects of Fenofibrate on activating phosphoinositide 3 kinase/protein kinase B（PI3K/Akt） signaling and peroxisome proliferator-activated receptor-α（PPAR-α） were also measured in renal IRI. The results showed that plasma levels of blood urea nitrogen and creatinine, histopathologic scores and the expression levels of TNF-α, IL-8 and IL-6 were significantly lower in FEN group than in IRI group. Moreover, Fenofibrate pretreatment could further induce PI3K/Akt signal pathway and PPAR-α activation following renal IRI. These findings indicated PPAR-α activation by Fenofibrate exerts protective effects on renal IRI in mice by suppressing inflammation via PI3K/Akt activation. Thus, Fenofibrate could be a novel therapeutic alternative in renal IRI.

Protective effects of panax notoginseng saponin on dextran sulfate sodium-induced colitis in rats through phosphoinositide-3-kinase protein kinase B signaling pathway inhibition

BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications.AIM To explore the protective effects of panax notoginseng saponin(PNS) against dextran sulfate sodium(DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B(PI3K/AKT) signaling pathway inhibition in rats.METHODS Colitis rat models were generated via DSS induction, and rats were divided into control(no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3 K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002.RESULTS Compared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers,and showed significantly increased M1 macrophages in spleen and colon tissues.They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway(all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency(all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group(P < 0.05).CONCLUSION PNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis.

Micro RNA-21 promotes phosphatase gene and protein kinase B/phosphatidylinositol 3-kinase expression in colorectal cancer

AIM: To explore the regulatory mechanism of the target gene of micro RNA-21(mi R-21), phosphatase gene(p TEN), and its downstream proteins, protein kinase B(AKT) and phosphatidylinositol 3-kinase(p I3K), in colorectal cancer(CRC) cells. METHODS: Quantitative real-time p CR(q RT-p CR) and Western blot were used to detect the expression levels of mi R-21 and p TEN in HCT116, HT29, Colo32 and SW480 CRC cell lines. Also, the expression levels of p TEN m RNA and its downstream proteins AKT and p I3 K in HCT116 cells after downregulating mi R-21 were investigated. RESULTS: Comparing the mi R-21 expression in CRC cells, the expression levels of mi R-21 were highest in HCT116 cells, and the expression levels of mi R-21 were lowest in SW480 cells. In comparing mi R-21 and p TEN expression in CRC cells, we found that the protein expression levels of mi R-21 and p TEN were inversely correlated(p < 0.05); when mi R-21 expression was reduced, m RNA expression levels of p TEN did not significantly change(p > 0.05), but the expression levels of its protein significantly increased(p < 0.05). In comparing the levels of p TEN protein and downstream AKT and p I3 K in HCT116 cells after downregulation of mi R-21 expression, the levels of AKT and p I3 K protein expression significantly decreased(p < 0.05). CONCLUSION: p TEN is one of the direct target genesof mi R-21. Thus, phosphatase gene and its downstream AKT and p I3 K expression levels can be regulated by regulating the expression levels of mi R-21, which in turn regulates the development of CRC.

Hippocampal activation of c-Jun N-terminal kinase,protein kinase B,and p38 mitogen-activated protein kinase in a chronic stress rat model of depression

Recent studies have shown that varied stress stimuli activate c-Jun N-terminal kinase （JNK）, protein kinase B （Akt）, and p38 mitogen-activated protein kinase （p38） signal transduction pathway, and also regulate various apoptotic cascades. JNK and p38 promote apoptosis, but Akt protects against apoptosis, in hippocampal neurons. However, changes in the transduction pathway in different regions of brain tissues in a chronic stress rat model of depression remain poorly understood. Results from this study showed that JNK phosphorylation levels were significantly greater in the stress group hippocampus compared with the control group （P 〈 0.05）. No significant difference in JNK phosphorylation levels was detected in the rat cerebral cortex between stress and control groups, and no significant difference in Akt and p38 phosphorylation levels was detected in the rat hippocampus and cerebral cortex between stress and control groups （P 〉 0.05）. These results suggested that the JNK signal pathway is activated by JNK phosphorylation and participates in pathophysiological changes in rat models of depression.

Cytotoxicity of nonylphenol on spermatogonial stem cells via phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathway

BACKGROUND With continuous advancement of industrial society,environmental pollution has become more and more serious.There has been an increase in infertility caused by environmental factors.Nonylphenol(NP)is a stable degradation product widely used in daily life and production and has been proven to affect male fertility.However,the underlying mechanisms therein are unclear.Thus,it is necessary to study the effect and mechanism of NP on spermatogonial stem cells(SSCs).AIM To investigate the cytotoxic effect of NP on SSCs via the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/AKT/mTOR)pathway.METHODS SSCs were treated with NP at 0,10,20 or 30μmol.MTT assay was performed to evaluate the effect of NP on the proliferation of SSCs.Flow cytometry was conducted to measure SSC apoptosis.The expression of Bad,Bcl-2,cytochrome-c,pro-Caspase 9,SOX-2,OCT-4,Nanog,Nanos3,Stra8,Scp3,GFRα1,CD90,VASA,Nanos2,KIT,PLZF and PI3K/AKT/mTOR-related proteins was observed by western blot,and the mRNA expression of SOX-2,OCT-4 and Nanog was detected by quantitative reverse transcription polymerase chain reaction.RESULTS Compared with untreated cells(0μmol NP),SSCs treated with NP at all concentrations showed a decrease in cell proliferation and expression of Bcl-2,Nanog,OCT-4,SOX-2,Nanos3,Stra8,Scp3,GFRα1,CD90,VASA,Nanos2,KIT,and PLZF(P<0.05),whereas the expression of Bad,cytochrome-c,and pro-Caspase 9 increased significantly(P<0.05).We further examined the PI3K/AKT/mTOR pathway and found that the phosphorylation of PI3K,AKT,mTORC1,and S6K was significantly decreased by NP at all concentrations compared to that in untreated SSCs(P<0.05).NP exerted the greatest effect at 30μmol among all NP concentrations.CONCLUSION NP attenuated the proliferation,differentiation and stemness maintenance of SSCs while promoting apoptosis and oxidative stress.The associated mechanism may be related to the PI3K/AKT/mTOR pathway.

Increased endothelin receptor B and G protein coupled kinase-2 in the mesentery of portal hypertensive rats

AIM: To elucidate the mechanisms of mesenteric vasodilation in portal hypertension (PHT), with a focus on endothelin signaling. METHODS: PHT was induced in rats by common bile duct ligation (CBDL). Portal pressure (PP) was measured directly via catheters placed in the portal vein tract. The level of endothelin-1 (ET-1) in the mesenteric circulation was determined by radioimmunoassay, and the expression of the endothelin A receptor (ETAR) and endothelin B receptor (ETBR) was assessed by immunofluorescence and Western blot. Additionally, expression of G protein coupled kinase-2 (GRK2) and β-arrestin 2, which influence endothelin receptor sensitivity, were also studied by Western blot. RESULTS: PP of CBDL rats increased significantly (11.89 ± 1.38 mmHg vs 16.34 ± 1.63 mmHg). ET-1 expression decreased in the mesenteric circulation 2 and 4 wk after CBDL. ET-1 levels in the systemic circulation of CBDL rats were increased at 2 wk and decreased at 4 wk. There was no change in ETAR expression in response to CBDL; however, increased expression of ETBR in the endothelial cells of mesenteric arterioles and capillaries was observed. In sham-operated rats, ETBR was mainly expressed in the CD31+ endothelial cells of the arterioles. With development of PHT, in addition to the endothelial cells, ETBR expression was noticeably detectable in the SMA+ smooth muscle cells of arterioles and in the CD31+ capillaries. Following CBDL, increased expression of GRK2 was also found in mesenteric tissue, though there was no change in the level of β-arrestin 2. CONCLUSION: Decreased levels of ET-1 and increased ETBR expression in the mesenteric circulation following CBDL in rats may underlie mesenteric vasodilation in individuals with PHT. Mechanistically, increased GRK2 expression may lead to desensitization of ETAR, as well as other vasoconstrictors, promoting this vasodilatory effect.

Telencephalin protects PAJU cells from amyloid beta protein-induced apoptosis by activating the ezrin/radixin/moesin protein family/phosphatidylinositol-3-kinase/protein kinase B pathway

Telencephalin is a neural glycoprotein that reduces apoptosis induced by amyloid beta protein in the human neural tumor cell line PAJU. In this study, we examined the role of the ezrin/radixin/moesin protein family/phosphatidylinositol-3-kinase/protein kinase B pathway in this process. Western blot analysis demonstrated that telencephalin, phosphorylated ezrin/radixin/moesin and phosphatidylinositol-3-kinase/protein kinase B were not expressed in PAJU cells transfected with empty plasmid, while they were expressed in PAJU cells transfected with a telencephalin expression plasmid. After treatment with 1.0 nM amyloid beta protein 42, expression of telencephalin and phosphorylated phosphatidylinositol-3-kinase/protein kinase B in the transfected cells gradually diminished, while levels of phosphorylated ezrin/radixin/moesin increased. In addition, the high levels of telencephalin, phosphorylated ezrin/radixin/moesin and phosphatidylinositol-3-kinase/protein kinase B expression in PAJU cells transfected with a telencephalin expression plasmid could be suppressed by the phosphatidylinositol-3-kinase inhibitor LY294002. These findings indicate that telencephalin activates the ezrin/radixin/moesin family/phosphatidylinositol-3-kinase/protein kinase B pathway and protects PAJU cells from amyloid beta protein-induced apoptosis.

Inhibitory roles of protein kinase B and peroxisome proliferator-activated receptor gamma coactivator on hepatic HMG-CoA reductase promoter activity

Since we had previously demonstrated that siRNAs to tristetraprolin (TTP) markedly inhibited insulin stimulation of hepatic HMG-CoA reductase (HMGR) transcription, we investigated the effects of transfecting rat liver with TTP constructs. We found that transfecting diabetic rats with TTP did not increase HMGR transcription but rather led to modest inhibition. We then investigated whether co-transfection with protein kinase B, hepatic form (AKT2), might lead to phosphorylation and result in activation of HMGR transcription. We found that this treatment resulted in near complete inhibition of transcription. Transfection with peroxisome proliferator-activated receptor g coactivator (PGC-1a) also inhibited HMGR transcription. These results show that although TTP is needed for activation of HMGR transcription, it cannot by itself activate this process. AKT2 and PGC-1a, which mediate the activation of gluconeogenic genes by insulin, exert the opposite effect on HMGR.

Effects of Dendrobium candidum polysaccharides on microRNA-125b and mitogen-activated protein kinase signaling pathways in diabetic cataract rats

Background:Diabetic cataract is a common complication and a lens disorder in diabetes.Moreover,Dendrobium officinale polysaccharide(DOP)is found to alleviate diabetes complications.Consequently,microRNA-125b and mitogen-activated protein kinase signaling pathways play significant roles in diabetes.However,the mechanism and the effect of DOP on diabetic cataract remains unknown.Methods:Wistar male rats were randomly assigned to the control,model,and DOP groups.Diabetes was induced with streptozotocin.Furthermore,DOP was orally given for 12 weeks.The Lens Opacities Classification System III was used to evaluate lens opacity by slit-lamp microscope.The lens was then harvested for testing the mRNA expression of microRNA-125b,ERK1,ERK2,Raf and Ras using reverse transcription-polymerase chain reaction.The protein expression of ERK1,ERK2,Raf,and Ras was detected using the Western blot analysis.The targets of microRNA-125b were predicted in miRWalk 2.0.These targets were obtained from the Kyoto Encyclopedia of Genes and Genomes pathway.Results:The lens opacities of the rats in the control group were almost at C0N0.Moreover,the majority of the lens opacities in the model group were C3 to C4 and N1 to N2,and were mostly at C1 to C2 and N0 to N1 in the DOP group.The difference was statistically significant(P<0.05).Furthermore,the microRNA-125b expression in the model group is significantly higher compared with the control group.Conversely,the microRNA-125b expression in the DOP group is significantly decreased(all P<0.05).The mRNA expression of ERK1,ERK2,Raf,and Ras in the model groups were upregulated compared with those of the control group.However,the ERK1 and Raf mRNA expressions of the DOP group were lower compared with the model group(all P<0.05).The protein expression of ERK1,Raf,and Ras in the model group was significantly increased compared with those of the control group.The protein expression of ERK1,Raf,and Ras in the DOP group was significantly lower compared with the model group(all P<0.05).Moreover,3,378 genes of the microRNA-125b target were gained from the miRWalk.After Kyoto Encyclopedia of Genes and Genomes pathways analysis in Gene Set Enrichment Analysis,246 items were gained including Ras(rno04014)and mitogen-activated protein kinase(rno04010)signaling pathways.A positive correlation exists between microRNA-125b and mRNA expression of ERK1,ERK2,Raf and Ras(r=0.940,0.841,0.666,and 0.768;all P<0.05).Conclusion:DOP can alleviate the severity of the opacity of the lens in diabetic cataract rats via microRNA-125b and mitogen-activated protein kinase signaling pathways.Thus,microRNA-125b has something to do with the mitogen-activated protein kinase signaling pathway.

An Experimental Study on the Role of Nuclear Factor-κB in the Signal Conduction of Protein Kinase C Regulating the Proliferation and Apoptosis of T Lymphocytes in Asthma

To explore the role of nuclear factor-κB(NF-κB) in the signal pathway of protein kinase C (PKC) regulating the proliferation and apoptosis of T lymphocytes in asthma. T lymphocytes were isolated from the asthmatic model of guinea pigs and the asthmatic patients. Either the T cells stimulated with PMA alone or those stimulated with PMA together with pyrrolidine dithiocarbamate (PDTC) were incubated for 1 and 24?h. The proliferation of and the presence of NF-κB in the cells incubated for 1?h were observed by MTT and immunohistochemical staining, respectively. And the cells incubated for 24?h were observed for the apoptosis by TUNEL. All the assays were paralleled with controls, and all the data were analyzedstatistically with the software SAS. The percentage of cells of nuclear positive staining of NF-κB and the proliferation of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated with PMA were significantly higher than those of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated without PMA respectively (P<0.01) and those of T lymphocytes from normal control guinea pigs and normal control persons stimulated with PMA respectively (P<0.01), and were significantly reduced by PDTC (P<0.01). The apoptosis index of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated with PMA were significantly lower than those of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated without PMA respectively (P<0.01) and those of T lymphocytes from normal control guinea pigs and normal control persons stimulated with PMA respectively (P<0.01), and were significantly induced by PDTC (P<0.01). There were good positive correlation between the percentage of cells of nuclear staining of NF-κB of T lymphocytes and the proliferation of T lymphocytes (r=0.51-0.72, P<0.001), and also good negative correlation between the percentage of cells of nuclear staining of NF-κB and the apoptosis index of T lymphocytes (r=-0.55-0.71, P<0.001, respectively). It concludes that the active PKC of asthmatic T lymphocytes promoting the proliferation and inhibiting the apoptosis of T lymphocytes may be mediated by activating NF-κB, the activation of PKC-NF-κB signal pathway of T lymphocytes NF-κB may play an important role in the pathogenesis of asthma.

淫羊藿苷调控mTOR/Akt/CREB通路对高糖诱导的足细胞自噬及凋亡的影响

目的 探讨淫羊藿苷对高糖诱导的足细胞自噬、凋亡及哺乳动物雷帕霉素靶蛋白(mTOR)/丝氨酸苏氨酸蛋白激酶(Akt)/环磷酸腺苷反应元件结合蛋白(CREB)通路的影响。方法 将小鼠足细胞MPC5分为5组:正常对照组(5.5 mmol·L^(-1)葡萄糖)、高糖组(30 mmol·L^(-1)葡萄糖)、淫羊藿苷组(30 mmol·L^(-1)葡萄糖+5μmol·L^(-1)淫羊藿苷)、GDC-0349组(30 mmol·L^(-1)葡萄糖+50μmol·L^(-1)GDC-0349)、淫羊藿苷+GDC-0349组(30 mmol·L^(-1)葡萄糖+5μmol·L^(-1)淫羊藿苷+50μmol·L^(-1)GDC-0349)。培养48 h后,噻唑蓝法检测MPC5细胞活力;吖啶橙染色观察MPC5细胞自噬情况;流式细胞术检测MPC5细胞凋亡;蛋白印迹法检测MPC5细胞自噬[微管相关蛋白1轻链3(LC3)Ⅱ、LC3Ⅰ、自噬相关蛋白(Beclin-1)]、凋亡[Bcl-2相关X蛋白(Bax)、B淋巴细胞瘤-2(Bcl-2)]和mTOR/Akt/CREB通路相关蛋白的表达。结果 与正常对照组比较,高糖组MPC5细胞活力、Bcl-2、磷酸化mTOR(p-mTOR)/mTOR、磷酸化Akt(p-Akt)/Akt、磷酸化CREB(p-CREB)/CREB蛋白表达水平显著降低(P<0.05),自噬能力增强,自噬体表现出橙色荧光,细胞凋亡率、LC3Ⅱ/LC3Ⅰ、Beclin-1、Bax蛋白表达水平显著升高(P<0.05)。与高糖组比较,淫羊藿苷组MPC5细胞活力、LC3Ⅱ/LC3Ⅰ、Beclin-1、Bcl-2、p-mTOR/mTOR、p-Akt/Akt、p-CREB/CREB蛋白表达水平显著升高,自噬能力进一步增强,自噬体数量增多,自噬体呈现出砖红色荧光(P<0.05),细胞凋亡率、Bax蛋白表达水平显著降低(P<0.05);GDC-0349组MPC5细胞活力、LC3Ⅱ/LC3Ⅰ、Beclin-1、Bcl-2、p-mTOR/mTOR、p-Akt/Akt、p-CREB/CREB蛋白表达水平显著降低,自噬能力减弱,自噬体数量减少,自噬体表现出橙色荧光(P<0.05),细胞凋亡率、Bax蛋白表达水平显著升高(P<0.05);淫羊藿苷+GDC-0349可逆转淫羊藿苷对高糖诱导MPC5细胞的作用效果(P<0.05)。结论 淫羊藿苷通过激活mTOR/Akt/CREB通路促进高糖诱导的足细胞自噬抑制细胞凋亡。

下调HMGB2表达对肝癌LM3细胞上皮-间质转化的抑制作用及其AKT/mTOR信号通路机制

目的:探讨下调肝癌细胞中高迁移率族框蛋白2 (HMGB2)表达对肝癌细胞生物学行为及上皮-间质转化(EMT)进程的影响,并阐明其作用机制。方法:对数生长期的人肝癌LM3细胞分为阴性对照组和HMGB2 RNA干扰组(HMGB2 siRNA组),分别以Lipofectamin 2000为载体转染无关序列的RNA寡核苷酸(RNA oligo)和敲除HMGB2序列的RNA oligo。采用实时荧光定量PCR(RT-qPCR)法和Western blotting法检测2组细胞中HMGB2 mRNA和蛋白表达水平,分别采用细胞划痕实验和Transwell小室实验检测2组细胞的迁移和侵袭能力,采用Western blotting法检测2组细胞中E-钙黏蛋白(E-cadherin)、 N-钙黏蛋白(N-cadherin)、波形蛋白(Vimentin)和蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)通路相关蛋白表达水平。结果:与阴性对照组比较,HMGB2 siRNA组细胞中HMGB2 mRNA和蛋白表达水平均明显降低(P<0.05),HMGB2 siRNA组细胞划痕愈合率明显降低(P<0.01),侵袭细胞数明显减少(P<0.01),细胞中E-cadherin蛋白表达水平明显升高(P<0.01),N-cadherin、Vimentin、mTOR、AKT和磷酸化AKT (p-AKT)蛋白表达水平明显降低(P<0.05或P<0.01)。结论:下调HMGB2的表达可降低肝癌LM3细胞迁移和侵袭能力并抑制EMT,其作用机制可能与参与调节AKT/mTOR通路相关蛋白表达有关。

黄芪阳和汤调控PI3K/AKT/NF-κB信号通路促进糖尿病足溃疡大鼠创面愈合

目的基于磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/核因子-κB(NF-κB)信号通路探究黄芪阳和汤对糖尿病足溃疡(DFU)大鼠创面愈合的影响。方法构建DFU大鼠模型,将建模成功的48只大鼠随机分为模型组,黄芪阳和汤低(8.5 g/kg)、高(17 g/kg)剂量组,黄芪阳和汤高剂量(17 g/kg)+LY294002(PI3K/AKT通路抑制剂,0.3 mg/kg)组;每组12只;另取12只大鼠为对照组。各组大鼠给予对应药物干预,连续4周。第14、28天给药后,观察大鼠一般状态及创面变化,计算创面愈合率,检测大鼠空腹血糖(FBG)水平和大鼠创面周围组织经皮氧分压(TcpO2);酶联免疫吸附试验检测大鼠血清血管内皮生长因子(VEGF)、缺氧诱导因子-1α(HIF-1α)、C反应蛋白(CRP)、白细胞介素(IL)-6水平;苏木素-伊红染色观察大鼠创面组织病理学变化;免疫组织化学染色测定大鼠创面组织微血管密度;蛋白免疫印迹法检测大鼠创面组织中PI3K、磷酸化PI3K(p-PI3K)、AKT、磷酸化AKT(p-AKT)、NF-κB p65、磷酸化NF-κB p65(p-NF-κB p65)、NF-κB抑制蛋白α(IκB-α)蛋白表达。结果对照组大鼠毛色光滑,饮食、饮水、排泄均正常,较活跃,创面愈合快,创面组织炎症反应较轻,新生血管较多,肉芽组织中成纤维细胞及胶原基质丰富;模型组大鼠毛色暗淡无光泽,活动减少,且出现多饮、多食、多尿症状,创面颜色较深,且周围组织出现水肿、溃疡,创面组织可见大量炎性细胞浸润,伴组织坏死、渗出,新生血管及成纤维细胞较少,创面愈合率、创面周围组织TcpO2、血清VEGF、HIF-1α、创面组织微血管密度、p-PI3K、p-AKT、IκB-α蛋白表达水平降低,FBG、血清CRP、IL-6、创面组织p-NF-κB p65蛋白表达升高(P<0.05);与模型组相比,黄芪阳和汤低、高剂量组大鼠状态逐渐改善,创面组织病变程度依次减轻,创面愈合率、创面周围组织TcpO2、血清VEGF、HIF-1α、创面组织微血管密度、p-PI3K、p-AKT、IκB-α蛋白表达水平依次升高,FBG、血清CRP、IL-6、创面组织p-NF-κB p65蛋白表达依次降低(P<0.05);LY294002能部分逆转高剂量黄芪阳和汤对DFU大鼠的治疗作用(P<0.05)。结论黄芪阳和汤能调控PI3K/AKT/NF-κB信号通路,抑制DFU大鼠炎症反应,促进血管新生,从而促进创面愈合。

基于BDNF/TrkB/CREB通路研究六味地黄丸对丙戊酸钠诱导的孤独症谱系障碍模型仔鼠的作用机制

目的基于脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)/酪氨酸激酶受体B(tyrosine kinase receptor B,TrkB)/cAMP反应元件结合蛋白(cAMP response element binding protein,CREB)通路,探讨六味地黄丸对丙戊酸钠(sodium valproate,VPA)诱导的孤独症谱系障碍(autism spectrum disorder,ASD)仔鼠的作用机制。方法将13只SD孕鼠随机分为两组,其中10只孕鼠在第12.5天时腹腔注射VPA溶液(600 mg·kg^(-1))为VPA组,另外3只孕鼠注射等体积生理盐水为对照组。第21天对两组雄性仔鼠开展行为学检测,筛选出符合ASD疾病模型的仔鼠30只,随机分为模型组(等体积生理盐水),维生素D组(1480 IU·kg^(-1)),六味地黄丸高(3 g·kg^(-1))、中(1.5 g·kg^(-1))、低(0.75 g·kg^(-1))剂量组,每组6只。正常雄性仔鼠6只,设为空白组(等体积生理盐水)。各组仔鼠连续灌胃14 d,1次/d,给药后再次开展行为学检测。尼氏染色观察各组仔鼠海马组织神经元形态学变化,比色法检测各组仔鼠海马组织中谷氨酸(glutamic acid,GLU)、γ-氨基丁酸(gamma-aminobutyric acid,GABA)含量;qRT-PCR检测各组仔鼠海马组织中BDNF、TrkB、CREB mRNA相对表达。结果与对照组比较,VPA组仔鼠体质量、身长、尾长更小(P<0.05)。与空白组比较,模型组社交障碍症状明显(P<0.01),焦虑障碍症状明显(P<0.01),重复刻板行为增多(P<0.05或P<0.01),海马神经元结构损伤,GLU升高(P<0.01)、GABA下降(P<0.01),BDNF、TrkB、CREB mRNA表达降低(P<0.05或P<0.01);与模型组比较,维生素D组及六味地黄丸中、低剂量组仔鼠社交能力增强(P<0.05或P<0.01),焦虑障碍减轻(P<0.05或P<0.01),重复刻板行为减少(P<0.01或P<0.05),海马神经元结构明显复原,GLU下降(P<0.01),BDNF、TrkB、CREB mRNA表达增加(P<0.05或P<0.01),六味地黄丸中、低剂量组GABA上升(P<0.05或P<0.01)。结论六味地黄丸能显著改善VPA诱导的ASD仔鼠行为表现,增强海马组织神经元的再生与修复,其机制可能与平衡GLU、GABA水平,上调仔鼠海马组织中BDNF/TrkB/CREB的表达有关。

Expression of phosphatidylinositol-3 kinase and effects of inhibitor Wortmannin on expression of tumor necrosis factor-α in severe acute pancreatitis associated with acute lung injury

BACKGROUND: Acute lung injury(ALI) is a common and serious complication of severe acute pancreatitis(SAP). The study aimed to investigate the protective effect and mechanism of phosphatidylinositol-3 kinase(PI3K) inhibitor Wortmannin in SAP associated with ALI.METHODS: Ninety rats were randomly divided into three groups: sham operation(SO) group(n=30), SAP group(n=30), and SAP+Wortmannin(SAP+W) group(n=30). SAP model was induced by retrograde injection of 4% sodium taurocholate into the biliopancreatic duct of rats. The rate of lung water content, myeloperoxidase(MPO), matrix metalloproteinase 9(MMP-9), protein kinase B(PKB), abdphosphorylation of protein kinase B(P-PKB) activity in the lung tissue were evaluated.RESULTS: In the SAP group, the p-PKB expression in the lung tissue began to rise at 3 hours after modeling, and peaked at 12 hours(P<0.05); the rate of lung water content, MPO and TNF-α activity were also gradually increased, and the degree of lung lesion gradually increased(P<0.05). In the SAP+Wortmannin group, the p-PKB expression in the lung tissue began to rise at 3 hours after modeling, and peaked at 12 hours; it was higher than that in the SO group(P<0.05), but significantly lower than that in the SAP group(P<0.05). The rest indicators in the SAP+Wortmannin group were also significantly decreased as compared with the SAP group(P<0.05).CONCLUSIONS: The expression of phosphatidylinositol-3 kinase/protein kinase B was elevated in severe pancreatitis rats with lung injury. This suggested that PI3 K signal transduction pathway is involved in the control and release of proinfl ammatory cytokines TNF-α, which may play an important role in the pathogenesis of severe acute pancreatitis associated with lung injury. This finding indicated that Wortmannin can block the PI3 K signal transduction pathway, and inhibit the release of infl ammatory factor TNF-α.