Geniposide attenuates cognitive dysfunction in sleep-deprived rats by inhibiting TLR4/NF-κB signaling pathway

AIM To investigate the effects of geniposide （Gen） on Toll like receptor 4/nuclear factor-κB （TLR4/NF-κB） signaling pathway and cognitive dysfunction in sleep deprived rats. METHODS Wistar rats （n=120） were randomly divided into normal control （NC） group, model （M） group, low-dose （5 g·kg^-1·d^-1） Gen （Gen-L） group, medium-dose （10 g·kg^-1·d^-1） Gen （Gen-M） group, high-dose （20 g·kg^-1·d^-1） Gen （Gen-H） group and Gen-H+LPS （0.4 mg·kg^-1·d^-1, tail vein injection） group. After 7 days of intervention, the sleep deprivation model of rats in M group, Gen-L, Gen-M, Gen-H and Gen-H+LPS group was established by improved small platform water environment. The escape latency of Morris water maze experiment and the behavior correct rate of Y maze experiment were measured. The serum levels of S100B and neuron-specific enolase （NSE）, and the levels of interleukin-1β （IL-1β）, IL-6 and tumor necrosis factor-α （TNF-α） in hippocampus were detected by ELISA. The mRNA levels of TLR4 and NF-κB p65 were detected by RT-qPCR, and the protein levels of TLR4 and NF-κB p65 were determined by Western blot. RESULTS Compared with NC group, the escape latency, the serum levels of S100B and NSE, the hippocampal levels of IL-1β, IL-6 and TNF-α, and the mRNA and protein expression of TLR4 and NF-κB p65 were increased significantly in M group （P<0.01）, and the behavior correct rate was decreased significantly （P<0.01）. Compared with M group, the escape latency, the hippocampal levels of IL-1β, IL-6 and TNF-α, and the expression of TLR4 and NF-κB p65 at mRNA and protein levels were decreased significantly in Gen-L, Gen-M and Gen-H groups （P<0.01）, and the behavior correct rate was increased in turn （P<0.01）. Compared with Gen-H group, the escape latency, the serum levels of S100B and NSE, the hippocampal levels of IL-1β, IL-6 and TNF-α, and the expression of TLR4 and NF-κB p65 at mRNA and protein levels were increased significantly in Gen-H+LPS group （P<0.01）, and the behavior correct rate was decreased significantly （P<0.01）. CONCLUSION Geniposide may inhibit the TLR4/NF-κB p65 signaling pathway to effectively improve cognitive function in sleep-deprived rats and reduce hippocampus inflammation.     

Protective effect of gabexate mesilate on blood-brain barrier in rats with cerebral ischemia-reperfusion

AIM To investigate the protective effects of gabexate mesilate （GM） on blood-brain barrier （BBB） permeability in rat model with cerebral ischemia-reperfusion （I/R）. METHODS Adult male SD rats （n=180） were randomly divided into sham group, I/R group, nimodipine （NMP; 2 mg·kg^-1·d^-1） group and GM （5, 10 and 20 mg·kg^-1·d^-1） groups （n=30 in each group）. The rat model of cerebral I/R was established by blocking the middle cerebral artery with thread plug for 2 h. Ten min before modeling, the drugs were given intraperitoneally. The nerve function was detected by Longa scoring method. The permeability of BBB was measured by Evans blue permeation method, and the brain water content was measured by dry-wet weight method. The activity of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px）, and the content of malondialdehyde （MDA） in brain tissue were determined by biochemical analysis. The content of tumor necrosis factor-α （TNF-α）, interleukin-1β （IL-1β） and IL-6 was measured by ELISA. The mRNA expression of matrix metalloproteinase-2 （MMP-2）, MMP-9 and nuclear factor-κB （NF-κB） was detected by RT-PCR. The protein levels of MMP-2, MMP-9 and NF-κB were determined by Western blot. RESULTS Compared with I/R group, the Longa score, permeability of Evans blue and brain water content of the rats in GM （10 and 20 mg·kg^-1·d^-1） and NMP （2 mg·kg^-1·d^-1） groups were decreased. The activity of SOD and GSH-Px was increased, while the content of MDA was decreased. The content of TNF-α, IL-1β and IL-6 was decreased, and the mRNA and protein expression levels of MMP-2, MMP-9 and NF-κB were significantly down-regulated. Compared with NMP （2 mg·kg^-1·d^-1） group, the Longa score and permeability of Evans blue were decreased in GM （20 mg·kg^-1·d^-1） group, the activity of SOD was increased, and the content of MDA and TNF-α was decreased. The mRNA and protein expression levels of MMP-2, MMP-9 and NF-κB were down-regulated. All of the differences were significant （P<0.05 or P<0.01）. CONCLUSION GM has protective effect on BBB in the rats with cerebral I/R. Its mechanism may be related to inhibition of oxidative stress and inflammation, and down-regulation of MMP-2, MMP-9 and NF-κB expression.     

Protective effect of curcumin on MRL/lpr mice with lupus nephritis and its mechanism

AIM To observe the effect of curcumin （Cur） on lupus nephritis （LN） and its possible mechanism. METHODS Thirty 10-week-old MRL/lpr lupus mice were randomly divided into MRL/lpr group， Cur-L and Cur-H group with 10 mice in each group， and C57BL/6 mice （n=10） served as normal control （NC） group. The mice in Cur-L group and Cur-H group were given intragastric administration of Cur at 100 and 200 mg·kg^-1·d^-1 for 12 weeks， respectively， and the same volume of normal saline was given to the mice in NC group and MRL/lpr group. The urine protein was detected， and the morphological changes of the renal tissue were observed by HE staining after treatment. The levels of serum creatinine （SCr）， blood urea nitrogen （BUN） and serum anti-double-stranded DNA （dsDNA）， and interleukin-1β （IL-1β）， IL-6 and tumor necrosis factor-α （TNF-α） levels in serum and renal tissues were detected. The protein levels of p-IκB， NF-κB， NLRP3 and caspase-1 in the renal tissues were determined by Western blot. RESULTS Compared with MRL/lpr group， the content of urine protein in Cur groups was significantly reduced， and the renal injury was relieved. The SCr， BUN， serum anti-dsDNA， and the serum and renal levels of IL-1， IL-6 and TNF-α were all significantly reduced， and the protein levels of p-IκB， NF-κB， NLRP and caspase-1 in the renal tissue were significantly decreased （P<0.05）. CONCLUSION Cur has a certain protective effect on the kidney of MRL/lpr mice， and its mechanism may be related to the inhibition of NF-κB and NLRP3 signaling pathways.     

Curcumin inhibits Porphyromonas gingivalis LPS-induced inflammatory response in human gingival fibroblasts by up-regulating miR-124

AIM To investigate the effects of curcumin （Cur） on the inflammatory response of human gingival fibroblasts （HGFs） induced by Porphyromonas gingivalis （Pg） lipopolysaccharide （LPS） and the role of microRNA-124 （miR-124） in this process. METHODS The HGFs were divided into control group, LPS group （10 mg/L LPS） and LPS+Cur （20, 40 and 80 μmol/L） groups （10 mg/L LPS+corresponding dose of Cur）. After treatment for 24 h, CCK-8 assay was used to measure the cell viability. ELISA was used to measure the levels of interleukin-1β （IL-1β） and tumor necrosis factor-α （TNF-α） in the supernatant. The level of miR-124 in the cells was detected by RT-qPCR. The protein levels of nuclear factor kappa B （NF-κB） p-p65 in cytoplasm and nucleus were determined by Western blot, and the nuclear translocation of NF-κB p-p65 was evaluated by laser confocal microscopy. After transfection with mimic-NC or miR-124 mimic, the expression of miR-124 and NF-κB p-p65 protein in the cytoplasm and nucleus of the cells were also detected. RESULTS The cell viability, the level of miR-124 in the cells and NF-κB p-p65 protein level in cytoplasm of LPS group were lower than those in control group （P<0.05）, while the levels of IL-1β and TNF-α in the supernatant and NF-κB p-p65 protein level in the nucleus were higher than those in control group （P<0.05）. The cell viability, the level of miR-124 in cells and NF-κB p-p65 protein level in the cytoplasm of LPS+Cur （40 and 80 μmol/L） groups were higher than those in LPS group （P<0.05）, while the level of TNF-α in the supernatant and NF-κB p-p65 protein level in the nucleus were lower than those in LPS group （P<0.05）. The level of IL-1β in the supernatant of LPS+80 μmol/L Cur group was lower than that in LPS group （P<0.05）. The levels of miR-124 and NF-κB p-p65 protein level in the cytoplasm of miR-124 mimic group were higher than those in LPS group and mimic-NC group （P<0.05）, while the level of NF-κB p-p65 proteinlevel in the nucleus was lower than that in LPS group and mimic-NC group （P<0.05）. CONCLUSION Curcumin inhibits the inflammatory response of HGFs induced by Pg LPS, which may be achieved by up-regulating miR-124 and then inhibiting the nuclear translocation of NF-κB p-p65.     

PCDH10 inhibits proliferation of breast cancer MDA-MB-231 cells by NF-κB/cyclin D1 signaling pathway

AIM To investigate the inhibitory effect of protocadherin 10 （PCDH10） on proliferation of human breast cancer cells and its possible mechanism. METHODS RT-PCR was used to measure the mRNA expression levels of PCDH10 in 4 human breast cancer cell lines and normal mammary epithelial MCF-10A cells. The breast cancer cell line MDA-MB-231 with stable PCDH10 overexpression was constructed by recombinant lentivirus （pLV-PCDH10） infection, and blank control （blank） group and negative control （pLV-NC） group were also set up. The cell proliferation ability was detected using methyl thiazolyl tetrazolium （MTT） and colony formation experiments. The cell cycle was detected by flow cytometry. Western blot was used to determine the expression of cyclin D1, cyclin-dependent kinase 4 （CDK4）, nucear factor-κB p65 subunit （NF-κB p65） and NF-κB inhibitor α （IκBα）. RESULTS The mRNA expression levels of PCDH10 in 4 breast cancer cell lines were lower than that in normal mammary epithelial MCF-10A cells （P<0.05）. A breast cancer cell line MDA-MB-231 with stable PCDH10 overexpression was constructed successfully. Compared with negative control group, PCDH10 overexpression significantly inhibited cell proliferation, induced cell cycle arrest at G₁ phase, down-regulated the expression of cyclin D1 and CDK4, and decreased phosphorylation of NF-κB p65 and IκBα（P<0.05）. CONCLUSION PCDH10 inhibits the proliferation and blocks cell cycle progression of breast cancer cells by targeting NF-κB/cyclin D1 signaling pathway.     

Effects of Huanglian-jiedu decoction on TLR4/NF-κB signaling pathway and goblet cells of mucosa in rats with allergic rhinitis

AIM To investigate the effect of Huanglian-jiedu decoction （HLJD） on goblet cells and Toll-like receptor 4 （TLR4）/nuclear factor （NF）-κB signaling pathway in allergic rhinitis rats. METHODS The rat model of allergic rhinitis was made by ovalbumin. The model rats were divided into model group, low-, medium- and high-dose HLJD groups, and positive control drug group. The rats in low-, medium- and high-dose HLJD groups were given different doses（5, 10 and 20 g/kg, respectively） of crude drug by intragastric administration, the rats in positive control group was given fluticasone propionate nasal spray （50 μg per side）, and the rats in control group and model group were given normal saline, once per day for 10 days. The behaviors were observed and scored after modeling and treatment, the weight of nasal secretion was measured after the treatment. The goblet cells in nasal mucosa were observed by periodic acid-Schiff （PAS） staining. The morphological changes of nasal mucosa were observed by hematoxylin-eosin （HE） staining. The interleukin （IL）-4 and IL-5 levels in nasal mucosa were measured by ELISA. The mRNA levels of mouse calcium-activated chloride channel 3 （mCLCA3） and mucin 5AC （MUC5AC） were detected by RT-qPCR. The protein expression of TLR4 and NF-κB p65 was determined by Western blot. RESULTS After modeling, compared with control group, the behavioral scores in model group, low-, medium- and high-dose HLJD groups and positive control group were increased （P<0.05）. The eosinophils, neutrophils and lymphocytes in nasal mucosa were seriously infiltrated, inflammatory infiltration was obvious, and obvious small vessel dilatation and interstitial edema in model group were observed. With the increase in the dosage of HLJD, the lymphatic infiltration was obviously relieved, but the eosinophil and neutrophil infiltration still existed, and the inflammatory infiltration was relieved. Compared with control group, the behavioral score, nasal secretion, the relative proportion of goblet cells in the mucosa, the IL-4 and IL-5 levels, the mRNA levels of mCLCA3 and MUC5AC, and the protein expression of TLR4 and NF-κB p65 in the mucosa of model group were increased （P<0.05）. Compared with model group, the behavioral score, nasal secretion, the relative proportion of goblet cells in the mucosa, the IL-4 and IL-5 levels, the mRNA levels of mCLCA3 and MUC5AC, and the protein expression of TLR4 in the mucosa of low-, medium- and high-dose HLJD groups and positive control group were increased （P<0.05）, and the protein expression of NF-κB p65 in the mucosa of medium- and high-dose HLJD groups and positive control group was decreased （P<0.05）. CONCLUSION Huanglian-jiedu decoction reduces the relative proportion of goblet cells in the nasal mucosa of rats with allergic rhinitis, which may be achieved by inhibiting TLR4/NF-κB signaling pathway.     

Effects of simvastatin on proliferation of esophageal cancer cells through NF-κB p65 pathway

AIM To investigate the effects of simvastatin （SIM） on the proliferation of esophageal cancer Eca109 cells through NF-κB p65 pathway. METHODS Esophageal cancer Eca109 cells were cultured in vitro and treated with SIM at different concentrations （2 , 4, 8, 16 and 32 μmol/L）. The proliferation of Eca109 cells was measured by MTT assay and plate colony formation assay. The proliferation-related protein levels of cyclin D1, c-Myc, NF-κB p65 （p65） and IκB-α in the esophageal cancer Eca109 cells were determined by Western blot. ELISA was used to detect the levels of tumor necrosis factor α （TNF-α） and interleukin-6 （IL-6） in the culture supernatant of Eca109 cells. RESULTS Compared with control group, the inhibitory effects of SIM at 2 , 4 , 8 and 16 μmol/L on the viability of Eca109 cells were increased in a concentration-dependent and time-dependent manners （P<0.05）. Simultaneously, the inhibitory rates of SIM at 16 and 32 μmol/L on the viability of Eca109 cells showed no significant difference （P>0.05）. The inhibitory rates of SIM at 16 μmol/L on the viability of esophageal cancer cells was 50.61% at 48 h, which was closed to half of the inhibitory dose IC₅₀, and it was used as the optimum concentration and time for follow-up experiments. Compared with control group, the plate colony formation rate of Eca109 cells, the protein levels of cyclinD1, c-Myc, nuclear p65, TNF-α and IL-6 in 8 and 16 μmol/L groups were decreased, while the levels of cytosolic p65 and IκB-α proteins were increased （P<0.05）. No significant difference of plate colony formation rate in Eca109 cells, and the protein levels of cyclin D1, c-Myc, nuclear and cytoplasmic p65, IκB-α, TNF-α and IL-6 between 16 μmol/L SIM group and 32 μmol/L SIM group was observed （P>0.05）. CONCLUSION Simvastatin inhibits the proliferation of esophageal cancer Eca109 cells, and its mechanism may be related to up-regulation of IκB-α, down-regulation of cyclinD1 and c-myc, inhibition of p65 nuclear translocation, and the expression of TNF-α and IL-6 downstream of NF-κB p65 pathway.     

Metformin attenuates nerve injury in stroke rats by regulating SIRT1/PGC-1α signaling pathway via miR-29c

AIM To explore the inhibitory effect of metformin （MET） on nerve injury in rats with stroke and its mechanism. METHODS SD rats were randomly divided into sham group （n=15）, model group （n=30）, MET group （n=30）, MET+agomir-NC group （n=30） and MET+agomir group （n=30）. The modified Puisinelli four-vessel occlusion method was used to prepare the model of global ischemic stroke, while the blood vessels in sham rats were isolated without clamping the common artery. One week before modeling, the rats in MET group, MET+agomir-NC group and MET+agomir group were given intraperitoneal injection of 100 mg·kg^-1·d^-1 MET, 100 mg·kg^-1·d^-1 MET+40 nmol/d agomir-NC, 100 mg·kg^-1·d^-1 MET+40 nmol/d miR-29c agomir, respectively, and the rats in sham group and model group were given intraperitoneal injection of the same amount of normal saline. Each treatment in the above groups was given once a day, 0.2 mL each time, for 7 consecutive days. The neurological deficit scores were measured 24, 48 and 72 h after operation. HE staining was used to observe the morphological changes of the hippocampus, and the living neurons were counted. RT-qPCR was used to detect the expression level of miR-29c, and the mRNA levels of silent information regulator 1 （SIRT1） and peroxisome proliferator-activated receptor γ coactivator 1α （PGC-1α） in hippocampus. The protein expression levels of SIRT1 and PGC-1α were determined by Western blot. RESULTS At the same time point, compared with model group, the neurological deficit score in MET group was significantly decreased, and the survival rate of the neurons was significantly increased （P<0.05）. Compared with MET+agomir-NC group, the neurological deficit score in MET+agomir group was increased, and the survival rate of the neurons was significantly decreased （P<0.05）. With the prolongation of time, except for sham group, the neurological deficit score was increased and the survival rate of the neurons was decreased. At 72 h after operation, compared with sham group, the expression of miR-29c in hippocampus of model group was significantly increased, and the mRNA and protein expression levels of SIRT1 and PGC-1α were significantly decreased （P<0.05）. Compared with model group, the expression of miR-29c in hippocampus of MET group was significantly decreased, and the expression of SIRT1 and PGC-1α at mRNA and protein levels was significantly increased （P< 0.05）. Compared with MET+agomir-NC group, the expression of miR-29c in hippocampus of MET+agomir group was significantly increased, and the mRNA and protein expression of SIRT1 and PGC-1α was significantly decreased （P<0.05）. CONCLUSIONS MET alleviates nerve injury in stroke rats, which may be related to down-regulation of miR-29c and promotion of SIRT1/PGC-1α signaling pathway activation.     

RXRα agonist bexarotene inhibits atherosclerosis in ApoE-/- mice by regulating TGF-β1/Smad2 signaling pathway

AIM To observe the effect of retinoid X receptor α （RXRα） agonist bexarotene （Bex） on the proliferation of transforming growth factor β1 （TGF-β1）-induced vascular smooth muscle cells （VSMCs） and atherosclerosis in apolipoprotein E knockout （ApoE^-/-） mice, and to explore the underlying mechanism. METHODS Ten C57BL/6 mice were selected as normal control group, and 30 ApoE^-/- mice were randomly divided into 3 groups： ApoE^-/- group, ApoE^-/-+Bex5 （5 mg·kg^-1·d^-1 Bex） group and ApoE^-/-+Bex10 （10 mg·kg^-1·d^-1 Bex） group. Bex was intragastrically given once a day for 8 weeks. The levels of triglyceride （TG） and total cholesterol （TC） were determined by oxidase method, and select masking method was used to determine serum levels of low-density lipoprotein cholesterol （LDL-C） and high-density lipoprotein cholesterol （HDL-C）. The protein levels of TGF-β1, p-Smad2 and Smad2 were determined by Western blot. HE staining was used to observe the intima of the thoracic aorta. The VSMCs were cultured with tissue patch method, and the proliferation of VSMCs was measured by BrdU incorporation method. RESULTS The serum levels of TG, TC and LDL-C, and the expression of TGF-β1 and p-Smad2 in thoracic aorta in ApoE^-/- group were significantly higher than those in C57BL/6 group （P<0.01）. Bex increased p-Smad2 protein level in thoracic aorta in a dose-dependent manner, inhibited the intimal plaque formation and vascular medial proliferation, and decreased the plaque area in ApoE^-/- mice （P<0.01）. No significant difference in serum levels of TG, TC, HDL-C and LDL-C, and TGF-β1 and Smad2 expression in thoracic aorta among ApoE^-/- group, ApoE^-/-+Bex5 group and ApoE^-/-+Bex10 group was observed. TGF-β1 （0.1~10 μg/L） promoted the proliferation of VSMCs, while Bex （10^-9~10^-7 mol/L） inhibited TGF-β1 （5 μg/L）-induced proliferation of VSMCs in a concentration-dependent manner. Bex （10^-7 mol/L） synergistically promoted the protein level of p-Smad2 in VSMCs induced by TGF-β1 （P<0.01）, but inhibited TGF-β1-induced nuclear translocation of p-Smad2. CONCLUSION RXRα agonist Bex inhibits the formation of atherosclerosis in ApoE^-/- mice, and its mechanism may be related to the regulation of TGF-β1/Smad2 pathway.     

Activation of PPARs is involved in effect of bezafibrate on diabetic hepatopathy in mice

AIM: To investigate the effects of bezafibrate (BEZ) on diabetic hepatopathy in mice. METHODS: Diabetic hepatopathy model was established by a long-high-energy diet combined with streptozotocin (40 mg·kg^-1·d^-1× 5 d, ip), and then bezafibrate (75 mg·kg^-1·d^-1, ig) was supplemented for 4 weeks. Fasting blood glucose (FBG) was detected every week. The structure of liver was observed by HE staining, and the liver function was measured by observing the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Total cholesterol (TC), triglyceride (TG), insulin and HbA1c were determined by commercial kits, and then HOMA insulin resistance index (HOMA-IR) was calculated. The expression of peroxisome proliferator-activated receports (PPARs) at mRNA and protein levels was determined by RT-qPCR and Western blot, respectively. RESULTS: After 7 days of treatment with streptozotocin, the FBG level of the mice exceeded 11.1 mmol/L. At the end of the experiment, the structural deformation of the hepatocytes (containing abundant fat vacuoles, infiltrated by inflammatory cells, etc.) was observed, with the increases in insulin, HbA1c, HOMA-IR, TC, TG, ALT and AST in diabetic mice (P<0.01). Meanwhile, the expression of PPARα, PPARβ and PPARγ at mRNA and protein levels was decreased (P<0.01). Bezafibrate treatment markedly attenuated the structural and functional damages of the liver in the diabetic mice (P<0.01), and reduced the levels of FBG, insulin, HbA1c, HOMA-IR, TC and TG (P<0.05). Bezafibrate also up-regulated the expression of PPARα, PPARβ and PPARγ (P<0.01). CONCLUSION: Bezafibrate attenuates hepatic injury in diabetic mice via the activation of PPARs-related signaling pathway.     

Inhibitory effect of HET0016 on LPS-induced proliferation and migration of microglia

AIM To study the effects of HET0016 on the proliferation and migration of microglia stimulated by lipopolysaccharide (LPS). METHODS Primary microglia from neonatal SD rats were isolated, purified and cultured. CCK-8 assay was performed to detect the effect of HET0016 on the viability of microglia after treatment with LPS. The levels of 20-hydroxyeicosatetraenoic acid （20-HETE）, tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were measured by ELISA. The proportion of S phase was evaluated by flow cytometry. The cell migration ability was detected by Transwell assay and scratch wound healing assay. The protein expression of NF-κB p50 and p65 was determined by Western blot. RESULTS LPS induced the increases in the proliferation and migration of microglia and the release of inflammatory cytokines (P<0.05). Compared with LPS group, HET0016 inhibited the cell proliferation and migration (P<0.05), decreased the levels of TNF-α and IL-1β (P<0.05), and reduced the expression of NF-κB p50 and p65 (P<0.05). CONCLUSION HET0016 has inhibitory effects on the proliferation and migration of microglia induced by LPS, and reduces the release of inflammatory cytokines. The mechanism may be related to NF-κB signaling pathway.     

Effects of thalidomide on the expression of NF-κB and TNF-α in experimental hepatic fibrotic rats

AIM: To study the effects of thalidomide on the expressions of nuclear factor κB (NF-κB) and tumor necrosis factor-α (TNF-α) in rat liver fibrosis.METHODS: The fibrosis of rat liver was induced by intraperitoneal injection of carbon tetrachloride thrice weekly.Meanwhile thalidomide (10 mg·kg^-1·d^-1 or 100 mg·kg^-1·d^-1) was given daily by the intragastric route for 8 weeks.Serum alanine aminotransferase (ALT),aspartate aminotransferase (AST),prealbumin (PA),hyaluronic acid (HA) and laminin (LN),and hydroxyproline (HYP) contents in the liver,NF-κB p65 and α-smooth muscle actin (α-SMA) protein in the liver,IκBα and TNF-α protein in cytoplasm and NF-κB p65 protein in nucleus and TNF-α mRNA levels in the liver were studied.RESULTS: Compared with the model group,the Knodell score,serum ALT,AST,HA,LN levels and HYP contents in liver,NF-κB p65 protein in nucleus and α-SMA protein in the liver,and TNF-α mRNA and protein in the liver of rats given high dose of thalidomide were decreased significantly (P<0.01).Meanwhile PA level and IκBα protein in cytoplasm were elevated significantly (P<0.01).CONCLUSION: Thalidomide exerts its effect on the down-regulation of NF-κB-induced TNF-α via inhibiting dissociation and degradation of IκB and prevents liver fibrosis in rats.     

Inhibitory effect of Wendan decoction on atherosclerotic plaque formation in ApoE-/- mice by regulating expression of membrane proteins involved in reverse cholesterol transport

AIM To explore the anti-atherosclerotic mechanism of Wendan decoction based on reverse cholesterol transport. METHODS Eight-week-old apolipoprotein E gene knockout （ApoE^-/-） mice with high-fat diet and daily drug gavage were randomly divided into model group, simvastatin group, and low-, middle- and high-dose Wendan decoction groups, with 15 mice in each group. The C57BL/6 mice of the same age served as control group. The mice were weighed once every week. After 10 weeks, the mice were anesthetized with chloral hydrate. The serum were collected for lipid level examination. The atherosclerotic plaque buildup in aortic root and whole aorta was observed by HE staining and oil red O staining, respectively. The levels of proteins related to cholesterol transport, ATP-binding cassette transporter A1 （ABCA1） and caveolin-1 in the aorta, and scavenger receptor class B type I （SR-BI） and CD36 in the liver, were quantified by Western blot. RESULTS Wendan decoction at middle dose inhibited the increase in the body weight of ApoE^-/- mice fed with high-fat diet （P<0.05）. Wendan decoction at different doses significantly reduced the serum levels of triglyceride, total cholesterol and low-density lipoprotein cholesterol in the ApoE^-/- mice （P<0.05 or P<0.01）, but had no effect on serum high-density lipoprotein cholesterol level （P>0.05）. Wendan decoction at different doses inhibited the formation of atherosclerotic plaques in whole aorta of the ApoE^-/- mice （P<0.05 or P<0.01）. Middle- and high-dose Wendan decoction significantly inhibited the formation of atherosclerotic plaques in the aortic root （P<0.05）. Bedsides, Wendan decoction at different doses increased the protein level of ABCA1 and decreased the protein level of caveolin-1 in the aorta of the ApoE^-/- mice （P<0.01）. Middle- and high-dose Wendan decoction increased the liver protein level of SR-BI in the ApoE^-/- mice （P<0.01）. However, Wendan decoction at different doses had no effect on the liver protein level of CD36 in the ApoE^-/- mice （P>0.05）. CONCLUSION Wendan decoction reduces the body weight, serum lipid levels and formation of atherosclerotic plaques in ApoE^-/- mice fed with high-fat diet, and its mechanism is related to up-regulation of ABCA1 protein level in the aorta and SR-BI protein level in the liver as well as down-regulation of caveolin-1 protein level in the aorta.     

Nontypeable Hemophilus influenzae induces inflammatory response of bronchial epithelial cells via NF-κB activation and histone deacetylase activity reduction

AIM: To investigate the effect of nontypeable Hemophilus influenzae (NTHi) on the inflammatory response of bronchial epithelial cells, and to preliminarily explore its mechanism. METHODS: The human normal bronchial epithelial BEAS-2B cells were cultured, and the expression levels of interleukin-8 (IL-8) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in the supernatant were measured by ELISA and RT-qPCR after infection with NTHi at MOI=10. The levels of IκBα and the phosphoacetylation of histones were determined by Western blot, and then the expression of histone deacetylase (HDAC) and the enzyme activity of HDAC were detected. The binding activity of NF-κB and IL-8 was measured by electrophoretic mobility shift assay and chromatin immunoprecipitation. Finally, the expression levels of GM-CSF and IL-8 were measured after pretreatment with NF-κB and HDAC inhibitors. RESULTS: The expression levels of IL-8 and GM-CSF in the culture supernatant of BEAS-2B cells were significantly increased (P<0.05) after infection with NTHi at MOI=10. In addition, infection with NTHi significantly down-regulated the expression of cytoplasmic IκBα and enhanced the DNA-binding activity of NF-κB. The phosphoacetylation of histones H3 and H4 and the binding of IL-8 and RNA polymerase II were also significantly increased after infection with NTHi. The expression level and enzyme activity of intracellular HDAC were also significantly reduced (P<0.05) after infection with NTHi. The expression levels of GM-CSF and IL-8 were significantly reduced after pretreatment with NF-κB inhibitor (P<0.05), while the secretion of IL-8 was significantly increased after pretreatment with HDAC inhibitor (P<0.05). CONCLUSION: NTHi inhibits the expression and activity of HDAC by activating the NF-κB signaling pathway, and promotes the secretion of IL-8 and GM-CSF in bronchial epithelial cells, thereby aggravating the inflammatory response.     

Activation of NF-κB-iNOS/COX-2 signaling pathways is involved in impaired endothelium-dependent relaxation under high glucose condition

AIM To investigate the role of nuclear factor-κB （NF-κB）-inducible nitric oxide synthase （iNOS）/cyclooxygenase-2 （COX-2） signaling pathways in impaired endothelium-dependent relaxation under high glucose （HG） condition. METHODS The endothelium-dependent relaxation induced by acetylcholine （ACh） in phenylephrine-precontracted rat thoracic aortic ring was performed in the absence or presence of different inhibitors under HG （55 mmol/L glucose） condition, and then the maximal relaxation effect of ACh （E_max） and the negative logarithm of ACh concentration for inducing 50% of E_max （pD₂） were calculated. The structure of aorta was observed by HE staining and electron microscopy. The mRNA and protein expression was detected by RT-qPCR and Western blot, respectively. RESULTS The structure of endothelial cells was interrupted by HG. Meanwhile, ACh-induced vasodilatation was also impaired, in which the E_max and pD₂ were both decreased significantly （P<0.01）, accompanied by the up-regulation of NF-κB p65, iNOS and COX-2 expression at mRNA and protein levels （P<0.01）. The NF-κB inhibitor PDTC, iNOS inhibitor SMT, and COX-2 inhibitor meloxicam restored the ACh-induced vasodilatation under HG condition, in which the E_max and pD₂ were increased significantly （P<0.01）. Moreover, PDTC attenuated the pathological damage of endothelial structure, and down-regulated the expression levels of NF-κB p65, iNOS and COX-2 induced by HG （P<0.01）. CONCLUSION The activation of NF-κB-iNOS/COX-2 signaling pathways is involved in the impaired endothelium-dependent relaxation under HG condition.     

miR-92b-5p attenuates renal injury and inflammatory response in diabetic nephropathy rats by targeting HMGB1

AIM To investigate the effect of microRNA-92b-5p （miR-92b-5p） on renal injury and inflammatory response in diabetic nephropathy （DN） rats and its mechanism. METHODS The rats were divided into control group， DN group， lentiviral negative control （LV-NC） group， LV-miR-92b group， LV-high mobility group protein B1 （LV-HMGB1） group and miR-92b+HMGB1 group， with 15 rats in each group. After fasting for 12 h， the model rats were intraperitoneally injected with streptozotocin at dose of 60 mg/kg， and the control rats were intraperitoneally injected with an equal volume of citrate buffer. Three days later， the rats in each treatment group were intravenously injected with 100 μL LV-NC， LV-miR-92b and LV-HMGB1 （1×10¹¹ U/L） twice a week for 8 consecutive weeks. Urinary protein， blood glucose， blood urea nitrogen and serum creatinine were detected by an automatic biochemical analyzer. The expression of miR-92b-5p and HMGB1 mRNA was detected by RT-qPCR. The targeting relationship between miR-92b-5p and HMGB1 was verified by dual-luciferase reporter assay. HMGB1 expression in kidney tissue was detected by Western blot. The kidney damage was observed by HE staining. The apoptosis was detected by flow cytometry. The levels of interleukin-6 （IL-6）， IL-1β and tumor necrosis factor-α （TNF-α） in renal tissues were detected by ELISA. RESULTS In DN model rats， miR-92b-5p was down-regulated， while HMGB1 was highly expressed. There was a binding site between miR-92b-5p and HMGB1 3'-untranslated region. High expression of miR-92b-5p inhibited the luciferase activity of the wild-type HMGB1 plasmid （P<0.01）， but had no effect on the luciferase activity of the mutant HMGB1 plasmid. Compared with DN group， urinary protein， blood glucose， serum creatinine and blood urea nitrogen in LV-miR-92b group were significantly reduced （P<0.01）. The degree of hyperplasia， swelling and inflammatory cell infiltration of glomerular mesangium and basement membrane tubules， the apoptosis rate of renal tissues， and the content of IL-6， IL-1β and TNF-α in renal tissues were significantly decreased （P<0.01）. Co-transfection of LV-HMGB1 significantly reversed the effect of miR-92b-5p on DN rats. CONCLUSION miR-92b-5p reduces renal injury and inflammatory response in DN rats by targeting HMGB1 and down-regulating its expression.     

Effects of HSP90 on complement-mediated hypoxia/reoxygenation injury of H9c2 cardiomyocytes during hypoxic postconditioning

AIM To investigate the effects and mechanisms of heat shock protein 90 （HSP90） on complement-mediated hypoxia/reoxygenation （H/R） injury of rat H9c2 cardiomyocytes during hypoxic postconditioning （HPC）. METHODS Rat H9c2 cardiomyocytes were divided into 7 groups according to different treatments： （1） control group （cultured for 10 h under normal oxygen）; （2） H/R group （hypoxia for 4 h and reoxygenation for 6 h）; （3） HPC group （3 cycles of 5 min H/R after hypoxia for 4 h, followed by reoxygenation for 6 h）; （4） HPC+geldanamycin （GA） group （1 μmol/L HSP90 inhibitor GA was added 20 min before HPC）; （5） negative control group （empty plasmid was transfected before HPC）; （6） C3 over-expression group （C3a plasmid was transfected before HPC）; （7） C5 over-expression group （C5a plasmid was transfected before HPC）. Morphological changes of the H9c2 cells were detected by Hoechst 33242 staining. The effects of HPC on the apoptosis of H9c2 cells were examined by flow cytometry. The protein levels of HSP90, C3a, C5a, NF-κB p65, TNF-α, IL-1β, IL-6, Bcl-2 and Bax were determined by Western blot. RESULTS With up-regulation of HSP90, HPC significantly reduced H/R-induced apoptosis of the H9c2 cells, inhibited the expression of C3a, C5a, NF-κB p65, TNF-α, IL-1β, IL-6 and Bax, and increased the expression of Bcl-2. These effects were blocked by GA. The inhibitory effects of HPC on NF-κB p65 expression and H9c2 cell apoptosis were offset after over-expression of C3a or C5a. CONCLUSION HSP90 attenuates H/R injury of H9c2 cardiomyocytes by inhibiting complement-NF-κB signaling pathway during HPC.     

RIP1-mediated necroptosis regulates inflammatory response of renal tubular epithelial cells via NF-κB signaling pathway

AIM To investigate the effect of receptor-interacting protein 1 (RIP1)-mediated necroptosis on human kidney proximal tubular cell inflammation and its related mechanisms. METHODS Human kidney proximal tubular HK-2 cells were cultured in vitro, and stimulated with tumot tumor necrosis factor-α (TNF-α) and Z-VAD-FMK for 24 h. Lactate dehydrogenase (LDH) cytotoxicity assay was used to detect the percentage of necrosis. Western blot was used to detect the protein expression of RIP1, IKK-α and NF-κB p65. The protein levels of interleukin-1β (IL-1β) and monocyte chemoattractant protein-1 (MCP-1) were determined by Western blot and ELISA. Real-time PCR was used to detect the mRNA expression level of NF-κB p65. Furthermore, the RIP1 inhibitor necrostatin-1 (Nec-1) and the NF-κB specific inhibitor ammonium pyrrolidinedithiocarbamate (PDTC) were used, and the above indicators were also detected. RESULTS Compared with control group, the protein level of RIP1 was increased in TNF-α combined with Z-VAD-FMK stimulation group (T/Z group). The protein levels of IKK-α and NF-κB p65 were obviously increased, and the release of LDH was increased (P<0.01). Western blot and ELISA showed that the expression levels of IL-1β and MCP-1 were significantly increased (P<0.01). Real-time PCR showed that the mRNA expression level of NF-κB p65 was also obviously increased. After Nec-1 or PDTC stimulation (T/Z+N group or T/Z+P group), the release of LDH, and the expression levels of inflammation-related indicators IL-1β and MCP-1 were significantly decreased. The protein expression levels of IL-1β and MCP-1 were further reduced after treatment with the above 2 stimulati (T/Z+P/N group). CONCLUSION Under T/Z condition, RIP1-mediated necroptosis plays an important role in renal tubular inflammatory response, which may be partly achieved by regulating the activation of NF-κB signaling pathway.     

Ethanol extract from Cortex Albiziae attenuates mouse acute liver injury induced by carbon tetrachloride via modulation of NF-κB pathway

AIM:To investigate the protective effect of ethanol extract from Cortex Albiziae on acute liver injury, and to explore its possible mechanism. METHODS:Acute liver injury in mice was induced by single intraperitoneal injection of 25% carbon tetrachloride (olive oil solubilization). The effective parts of ethanol extract from Cortex Albizziae against acute liver injury were screened. The pathological changes of the liver tissues were examined by pathological sections with HE staining. The activity of total superoxide dismutase (T-SOD) and the content of malondialdehyde (MDA) of the liver tissues were detected, the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were mea-sured by ELISA, and the protein expression levels of NF-κB p65, Bcl-2 and Bax in the liver cells of the mice in each group were determined by Western blot. RESULTS:Compared with model group, the serum levels of AST and ALT in low-dose n-butanol phase of ethanol extract from Cortex Albiziae (AB-L, 4 mg·kg^-1·d^-1) group and high-dose n-butanol phase of ethanol extract from Cortex Albiziae (AB-H, 8 mg·kg^-1·d^-1) group were significantly decreased. The necrosis extent and degree of the hepatocytes and infiltration of inflammatory cells were significantly lower than that in model group. Compared with model group, the serum levels of TNF-α and IL-6 in AB-H group and AB-L group were significantly decreased (P<0.05). The protein level of NF-κB p65 in the nuclei of mouse liver cells in AB-H group and AB-L group were also decreased significantly (P<0.05). Compared with model group, the protein expression of Bax was decreased, the protein expression of Bcl-2 was increased, and the Bcl-2/Bax ratio was increased in AB-L group and AB-H group. CONCLUSION:The n-butanol phase of ethanol extract from Cortex Albiziae may protect the liver by reducing the activation of NF-κB p65, inhibiting the excessive release of inflammatory cytokines IL-6 and TNF-α, and decreasing hepatocyte apoptosis via regulating Bcl-2 and Bax expression.     

Effects of metformin combined with Ge Xia Zhu Yu decoction on TLR4/NF-κB signaling pathway in rats with polycystic ovary and insulin resis-tance

AIM: To study the effect of metformin (Met) combinated with Ge Xia Zhu Yu decoction on Toll-like receptor-4 (TLR-4)/nuclear factor-κB (NF-κB) signaling pathway in the rats with polycystic ovary syndrome (PCOS) and insulin resistance induced by dehydroepiandrosterone, and to explore the mechanisms. METHODS: PCOS rats (after induced by dehydroepiandrosterone, n=110) were randomly divided into 3 groups:model group (30 rats), Met treatment group (40 rats) and Met combinated with Ge Xia Zhu Yu decoction treatment (combination) group (40 rats). The rats in model group were given the same volume of 0.9% sodium chloride daily by gavage. The rats in Met group were given Met (270 mg·kg^-1·d^-1) by gavage. The rats in combination group were given Met (270 mg·kg^-1·d^-1) and Ge Xia Zhu Yu decoction (34.5 mg·kg^-1·d^-1) by gavage. All rats were continuously intervened for 28 d. After the intervention, blood glucose[fasting plasma glucose (FPG) and 2-hour postprandial blood glucose (2hPBG)] was measured. The mRNA expression levels of follicular epithelial NF-κB, TLR-4 and oxidized low-density lipoprotein (ox-LDL) were detected by RT-PCR. The serum levels of inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were also detected by ELISA. RESULTS: After the intervention, FPG, 2hPBG, and serum levels of IL-6, TNF-α and CRP in Met group and combination group were lower than those in model group (P<0.05), and those in combination group were lower than those in Met group (P<0.05). Meanwhile, the mRNA expression levels of follicular epithelial NF-κB, TLR-4 and ox-LDL in Met group and combination group were lower than those in model group (P<0.05), and those in combination group were lower than those in Met group (P<0.05). CONCLUSION: Treatment with Met combined with Ge Xia Zhu Yu decoction improves insulin resistance in PCOS rats by decreasing the levels of inflammatory factors in serum and epithelial cells of ovary and inhibiting the expression of NF-κB, TLR-4 and ox-LDL in epithelial tissue of ovary.