This study aimed to explore the potential mechanism of Berberis atrocarpa Schneid. anthocyanin against Alzheimer's disease(AD) based on network pharmacology, molecular docking technology, and in vitro experiments. Databases were used to screen out the potential targets of the active components of B. atrocarpa and the targets related to AD. STRING database and Cytoscape 3.9.0 were adopted to construct a protein-protein interaction(PPI) network and carry out topological analysis of the common targets. Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analyses were performed on the target using the DAVID 6.8 database. Molecular docking was conducted to the active components and targets related to the nuclear factor kappa B(NF-κB)/Toll-like receptor 4(TLR4) pathway. Finally, lipopolysaccharide(LPS) was used to induce BV2 cells to establish the model of AD neuroinflammation for in vitro experimental validation. In this study, 426 potential targets of active components of B. atrocarpa and 329 drug-disease common targets were obtained, and 14 key targets were screened out by PPI network. A total of 623 items and 112 items were obtained by GO functional enrichment analysis and KEGG pathway enrichment analysis, respectively. Molecular docking results showed that NF-κB, NF-κB inhibitor(IκB), TLR4, and myeloid differentiation primary response 88(MyD88) had good binding abilities to the active components, and malvidin-3-O-glucoside had the strongest binding ability. Compared with the model group, the concentration of nitric oxide(NO) decreased at different doses of malvidin-3-O-glucoside without affecting the cell survival rate. Meanwhile, malvidin-3-O-glucoside down-regulated the protein expressions of NF-κB, IκB, TLR4, and MyD88. This study uses network pharmacology and experimental verification to preliminarily reveal that B. atrocarpa anthocyanin can inhibit LPS-induced neuroinflammation by regulating the NF-κB/TLR4 signaling pathway, thereby achieving the effect against AD, which provides a theoretical basis for the study of its pharmacodynamic material basis and mechanism.
NF-kappa B ; Alzheimer Disease ; Network Pharmacology ; Anthocyanins ; Berberis ; Lipopolysaccharides ; Molecular Docking Simulation ; Myeloid Differentiation Factor 88 ; Neuroinflammatory Diseases ; Toll-Like Receptor 4 ; I-kappa B Proteins

This study aimed to further explore the relevant mechanism of action by network pharmacology integrated with animal experimental verification based on previous proven effective treatment of vertebral artery type of cervical spondylosis(CSA) by Panlongqi Tablets. Bionetwork analysis was performed to establish drug-disease interaction network, and it was found that the key candidate targets of Panlongqi Tablets were enriched in multiple signaling pathways related to CSA pathological links, among which phosphatidylinositol 3-kinase(PI3 K)/serine-threonine kinase(AKT/PKB) signaling pathway was the most significant. Further, mixed modeling method was used to build the CSA rat model, and the rats were divided into normal, model, Panlongqi Tablets low-, medium-and high-dose(0.16, 0.32, 0.64 g·kg~(-1)) and Jingfukang Granules(positive drug, 1.35 g·kg~(-1)) groups. After successful modeling, the rats were administered for 8 consecutive weeks. Pathological changes of rat cervical muscle tissues were detected by hematoxylin-eosin(HE) staining, and the content of interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), vascular endothelial cell growth factor(VEGF) and chemokine(C-C motif) ligand 2(CCL2) in rat serum and/or cervical tissues was determined by enzyme-linked immunosorbent assay(ELISA). Western blot was employed to detect the protein expression levels of chemokine(C-C motif) receptor 2(CCR2), PI3 K, AKT, phosphorylated AKT(p-AKT), I-kappa-B-kinase beta(IKK-beta/IKKβ), nuclear factor kappa B(NF-κB P65) and phosphorylated nuclear factor kappa B(NF-κB p-P65) in rat cervical tissues, and positive expression of p-NF-κB P65 in rat cervical muscle tissues was detected by immunofluorescence. The results showed that Panlongqi Tablets at different doses improved the degree of muscle fibrosis and inflammation in cervical muscle tissues of CSA rats, and reduced the content of inflammatory factors IL-1β, TNF-α, VEGF, CCL2 and CCR2 in serum and/or cervical tissues. The protein expression levels of PI3 K, p-AKT, IKKβ and p-NF-κB P65 as well as the nuclear entry of p-NF-κB P65 in cervical tissues were down-regulated. These findings suggest that Panlongqi Tablets can significantly inhibit the inflammatory response of CSA rats, and the mechanism of action may be related to the down-regulation of the activation of PI3 K/AKT signaling pathway.
Animals ; Drugs, Chinese Herbal ; I-kappa B Kinase/pharmacology* ; NF-kappa B/metabolism* ; Network Pharmacology ; Phosphatidylinositol 3-Kinases/metabolism* ; Protein Serine-Threonine Kinases ; Proto-Oncogene Proteins c-akt/metabolism* ; Rats ; Signal Transduction ; Spondylosis/drug therapy* ; Tumor Necrosis Factor-alpha/metabolism* ; Vascular Endothelial Growth Factor A/genetics* ; Vertebral Artery/metabolism*

Objective:b> To explore the effect and mechanism of activation of peripheral blood mononuclear cell (PBMC) Toll-like receptor (TLR3) signaling pathway in recombinant HBsAg (rHBsAg) immune response. Methods:b> White blood cells were collected from peripheral blood of 13 healthy donors in the preparation of blood products. PBMC was isolated and treated with Poly I:C (Poly I:C group) and PBS (control group) respectively. 48 h later, some cells were collected and the expressions of TLR3 signaling pathway proteins were detected by flow cytometry. After activating (Poly I:C group)/inactivating (control group) TLR3 signaling pathway, rHBsAg was given to both groups for 72 h, and the proportions of DC, T, B cells and their subsets in PBMC were detected by flow cytometry. Paired <i>ti>-test, paired samples wilcoxon signed-rank test and canonical correlation analyses were used for statistical analysis. Results:b> The percentage of TLR3 protein-positive cells (19.21%) and protein expression (8 983.95), NF-κB protein expression (26 193.13), the percentage of pNF-κB protein-positive cells (13.73%) and its proportion in NF-κB (16.03%), and the percentage of pIRF3 protein-positive cells (12.64%) and its proportion in IRF3 (21.80%) in Poly I:C group were higher than those in control group (11.54%, 8 086.00, 22 340.66, 8.72%, 9.71%, 9.57%, 19.12%) (<i>Pi><0.05), and the percentage of TRIF protein-positive cells (89.75%) and protein expression (304 219.54) were higher in Poly I:C group than in the control group (89.64%, 288 149.72) (<i>Pi>>0.05). After PBMC stimulation by rHBsAg, the proportions of mDC (2.90%), pDC (1.80%), B cell (5.31%) and plasma cell (67.71%) in Poly I:C group were significantly higher than those in the control group (1.83%, 0.81%, 4.23%, 58.82%) (<i>Pi><0.05). Results of canonical correlation analysis showed that the expression of TLR3 protein was positively correlated with the proportions of plasma cells, the expression of pIRF3 protein was positively correlated with the proportions of plasma cells and mDC, and the percentage of pNF-κB protein-positive cells and the percentage of pIRF3 protein-positive cells were positively correlated with the proportion of CD4⁺T cells. Conclusions:b> Poly I:C can activate TLR3/TRIF/NF-κB and TLR3/TRIF/IRF3 signaling pathway, promote the function of downstream signaling molecules, and then promote the maturation of DC, induce the immune responses of CD4⁺T cell, and promote the maturation and activation of B cells and the immune response of rHBsAg.
Adaptor Proteins, Vesicular Transport/pharmacology* ; Hepatitis B Surface Antigens ; Humans ; Immunity ; Leukocytes, Mononuclear/metabolism* ; NF-kappa B ; Poly I-C/pharmacology* ; Signal Transduction ; Toll-Like Receptor 3/metabolism* ; Toll-Like Receptors

OBJECTIVE: To investigate the effects of chemotherapeutic agents widely used in clinical practice on major histocompatibility complex class I-related chain A and B (MICA/B) expression in breast cancer cells, and to explore the molecular mechanisms involved. METHODS: We examined MICA/B mRNA and surface protein expressions in breast cancer cells treated with chemotherapeutic agents by real-time RT-PCR and flow cytometry respectively. The blocking effects of ataxia telangiectasia mutated and Rad3-related kinase (ATM/ATR) inhibitor caffeine and nuclear factor κB (NF-κB) inhibitor pynolidine dithiocarbamate (PDTC) on etoposide-upregulated MICA/B mRNA and surface protein expressions were investigated. Electrophoretic mobility shift assay (EMSA) was taken to investigate whether etoposide enhanced the binding of NF-κB to MICA/B gene promoter. RESULTS: Three topoisomerase inhibitors etoposide, camptothecin and doxorubicine upregulated MICA and MICB mRNA expressions in breast cancer cell MCF-7. Comparing to no-drug-treated cells, MICA mRNA levels increased to (1.68±0.17), (2.54±0.25) and (3.42±0.15) fold, and levels of MICB mRNA increased to (1.82±0.24), (1.56±0.05) and (5.84±0.57) fold respectively in cancer cells treated by etoposide at the concentrations of 5, 20 and 100 μmol/L (P<0.05). MICA and MICB mRNA levels also increased significantly when MCF-7 cells were incubated with camptothecin or doxorubicine at the specific concentrations (P<0.05). MICB mRNA expression also increased slightly in another breast cancer cell SK-BR-3 treated by topoisomerase II inhibitors etoposide and camptothecin (P<0.05). Furthermore, etoposide and camptothecin upregulated MICA/B surface protein expression in MCF-7 cells (P<0.05), and the upregulation was found in both living and apoptotic cells. Our study showed that etoposide induced-MICA/B expression in MCF-7 was inhibited by caffeine at different concentrations. When cancer cells were treated by caffeine with 1, 5 and 10 mmol/L, MICA mRNA levels decreased from (3.75±0.25) to (0.89±0.05), (0.81±0.02) and (0.48±0.04) fold respectively (P<0.001), and MICB mRNA levels decreased from (6.85±0.35) to (1.36±0.13), (0.76±0.06) and (0.56±0.03) fold (P<0.05), while MICA/B protein levels decreased from (3.42±0.05) to (1.32±0.03), (1.21±0.06) and (1.14±0.03) fold (P<0.001), indicating that etoposide-induced MICA/B expression was inhibited by ATM/ATR inhibitor. Similarly, NF-κB inhibitor PDTC also inhibited MICA/B mRNA and protein expressions induced by etoposide significantly when MCF-7 cells were incubated with PDTC at the concentrations of 10, 50 and 100 μmol/L (P<0.05), indicating that NF-κB was also involved in this process. EMSA showed that the binding of NF-κB to MICA/B promoter enhanced in MCF-7 cells after etoposide treatment. CONCLUSION Topoisomerase inhibitor increased MICA/B mRNA and protein expressions in breast cancer cells, indicating that chemotherapeutic agents might increase the recognizing and killing ability of immunocytes to breast cancer cells. ATM/ATR and NF-κB pathways might be involved in it.
Antineoplastic Agents/pharmacology* ; Ataxia Telangiectasia Mutated Proteins/physiology* ; Breast Neoplasms/genetics* ; Cell Line, Tumor ; Doxorubicin ; Etoposide/pharmacology* ; Histocompatibility Antigens Class I ; Humans ; I-kappa B Proteins ; NF-kappa B/physiology* ; RNA, Messenger ; Topoisomerase Inhibitors ; Up-Regulation

<b>OBJECTIVEb>The aim of this study is to investigate hepatic and renal toxicity of acrylamide (ACR) , the antagonistic effect and possible mechanism of N-acetylcysteine (NAC) on the toxicity.

<b>METHODSb>Forty female SD rats were randomly divided into four groups. All the rats were administrated by intraperitoneal(i.p.) injection and 1.5 hours later by gavage. The control group was administrated with 0.9% NaCl by i.p. injection and gavaged with 0.9% NaCl. The NAC group was administrated with 200 mg/kg NAC by injection and gavaged with 0.9% NaCl. The ACR group was administrated with 0.9% NaCl by injection and gavaged with 40 mg/kg ACR. The combined treatment group was administrated with 200 mg/kg NAC by i.p. injection and gavaged with 40 mg/kg ACR. The rats were administrated once a day for 2 weeks. After 24 hours of the last administration, the rats were decapitated. The blood was collected, the liver and kidney were separated. The body weight, organ coefficient and serum biochemical parameters were measured, and the pathological changes of the tissues were examined with a microscope. Then the expression of NF-&kappa;B p65, I&kappa;B-α and COX-2 were detected by Western blot.

<b>RESULTSb>From the second day to the end of the exposure, the body weight of rats in the ACR group was statistically lower than that in the control group (P<0.05) . Compared with the combined treatment group, the body weight in the ACR group statistically decreased in the second and third days (P < 0.05) . The liver and kidney organ coefficients in the ACR group were (4.159%±.371%) and (0.764%±0.068%) respectively, which increased statistically when compared with the control group (P < 0.05) . The contents of ALT, AST and Cr in the serum in the ACR group were (77.370±16.397) U/L、(379.410±57.817) U/L and (77.812±6.391) μmol/L respectively, which were not significantly different with those in the control group and the combined treatment group (P>0.05) . The content of BUN in the serum in the ACR group was (7.005±1.009) mmol/L, which was statistically higher than that in the control group (P<0.05) . Histopathology results showed unclear boundary and nucleus pyknosis in hepatocytes, loose and disordered structures of hepatic cords in the ACR group, but no obvious pathology changes were observed in the kidneys of each group. In the Western blot results, the expression of nuclear NF-&kappa;B p65 and COX-2 in the liver in the ACR group was statistically higher than that in the control group and the combined treatment group (P<0.05) , and the expression of I&kappa;B-α in the liver in the ACR group statistically decreased compared with the control group and the combined treatment group (P<0.05) . The expression of total NF-&kappa;B p65 in the liver in the ACR group was statistically higher than that in the control group (P<0.05) .

<b>CONCLUSIONb>Under the conditions of this experiment, ACR may induce hepatic toxicity through the activation of NF-&kappa;B signaling pathway, and NAC could antagonize the hepatic toxicity of ACR by inhibiting the NF-&kappa;B signaling pathway, whereas the toxic effect of ACR on kidney needs to be further studied.

Acetylcysteine ; pharmacology ; Acrylamide ; toxicity ; Animals ; Cyclooxygenase 2 ; metabolism ; Female ; I-kappa B Proteins ; metabolism ; Kidney ; drug effects ; metabolism ; pathology ; Liver ; drug effects ; metabolism ; NF-KappaB Inhibitor alpha ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Transcription Factor RelA ; metabolism

Berberine (BBR) is an isoquinoline alkaloid extracted from Rhizoma coptidis and has been used for treating type 2 diabetes mellitus (T2DM) in China. The development of T2DM is often associated with insulin resistance and impaired glucose uptake in peripheral tissues. In this study, we examined whether BBR attenuated glucose uptake dysfunction through the cholinergic anti-inflammatory pathway in HepG2 cells. Cellular glucose uptake, quantified by the 2-[N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)-amino]-2-deoxy-D-glucose (2-NBDG), was inhibited by 21% after HepG2 cells were incubated with insulin (10(-6) mol/L) for 36 h. Meanwhile, the expression of alpha7 nicotinic acetylcholine receptor (α7nAChR) protein was reduced without the change of acetylcholinesterase (AChE) activity. The level of interleukin-6 (IL-6) in the culture supernatant, the ratio of phosphorylated I-kappa-B kinase-β (IK&kappa;β) Ser181/IKKβ and the expression of nuclear factor-kappa B (NF-&kappa;B) p65 protein were also increased. However, the treatment with BBR enhanced the glucose uptake, increased the expression of α7nAChR protein and inhibited AChE activity. These changes were also accompanied with the decrease of the ratio of pIKKβ Ser181/IKKβ, NF-&kappa;B p65 expression and IL-6 level. Taken together, these results suggest that BBR could enhance glucose uptake, and relieve insulin resistance and inflammation in HepG2 cells. The mechanism may be related to the cholinergic anti-inflammatory pathway and the inhibition of AChE activity.
Berberine ; pharmacology ; Glucose ; metabolism ; Hep G2 Cells ; Humans ; Hypoglycemic Agents ; pharmacology ; I-kappa B Kinase ; metabolism ; I-kappa B Proteins ; metabolism ; Insulin ; metabolism ; Insulin Resistance ; Interleukin-6 ; metabolism ; Transcription Factor RelA ; metabolism ; alpha7 Nicotinic Acetylcholine Receptor ; genetics ; metabolism

<b>OBJECTIVEb>This study observed attenuating effect of hydroxysafflor yellow A (HSYA), an effective ingredient of aqueous extract of Carthamus tinctorius L, on lipopolysaccharide (LPS)-induced endothelium inflammatory injury.

<b>METHODSb>Eahy926 human endothelium cell (EC) line was used; thiazolyl blue tetrazolium bromide (MTT) test was assayed to observe the viability of EC; Luciferase reporter gene assay was applied to measure nuclear factor-&kappa;B (NF-&kappa;B) p65 subunit nuclear binding activity in EC; Western blot technology was used to monitor mitogen activated protein kinase (MAPKs) and NF-&kappa;B activation. Reverse transcription polymerase chain reaction (RT-PCR) method was applied to observe intercellular cell adhesion molecule-1 (ICAM-1) and E-selectin mRNA level; EC surface ICAM-1 expression was measured with flow cytometry and leukocyte adhesion to EC was assayed with Rose Bengal spectrophotometry technology.

<b>RESULTSb>HSYA protected EC viability against LPS-induced injury (P <0.05). LPS-induced NF-&kappa;B p65 subunit DNA binding (P <0.01) and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor α (I&kappa;Bα) phosphorylation was inhibited by HSYA. HSYA attenuated LPS triggered ICAM-1 and E-selectin mRNA levels elevation and phosphorylation of p38 MAPK or c-Jun N-terminal kinase MAPK. HSYA also inhibited LPS-induced cell surface ICAM-1 protein expression P <0.01) and leukocyte adhesion to EC (P <0.05).

<b>CONCLUSIONb>HSYA is effective to protect LPS-induced high expression of endothelium adhesive molecule and inflammatory signal transduction.

Cell Adhesion ; drug effects ; Cell Nucleus ; drug effects ; metabolism ; Cell Survival ; drug effects ; Chalcone ; analogs & derivatives ; chemistry ; pharmacology ; therapeutic use ; E-Selectin ; genetics ; metabolism ; Endothelium, Vascular ; drug effects ; pathology ; Gene Expression Regulation ; drug effects ; Human Umbilical Vein Endothelial Cells ; drug effects ; metabolism ; pathology ; Humans ; I-kappa B Proteins ; metabolism ; Inflammation ; drug therapy ; pathology ; Intercellular Adhesion Molecule-1 ; genetics ; metabolism ; Leukocytes ; cytology ; drug effects ; Lipopolysaccharides ; MAP Kinase Signaling System ; drug effects ; NF-KappaB Inhibitor alpha ; Phosphorylation ; drug effects ; Protective Agents ; pharmacology ; Protein Binding ; drug effects ; Quinones ; chemistry ; pharmacology ; therapeutic use ; RNA, Messenger ; genetics ; metabolism

<b>OBJECTIVEb>To observe mainfestations of syndrome and biochemical indices of hypertensive model rats with excessive accumulation of phlegm-dampness syndrome (EAPDS), and to explore its possible pathological mechanism.

<b>METHODSb>EAPDS rat model was prepared in 50 Wistar rats by feeding with high fat forage. Meanwhile, a normal control group consisting of 10 Wistar rats was set up by feeding with normal forage. After 25-week continuous feeding, 22 rats with body weight (BW) and blood pressure (BP) exceeding 25% those of the control group were selected as a model group. BW, BP, blood lipids, and related serological indicators were detected in all rats. Morphological changes of target organs were observed. mRNA expression levels of leptin receptor (LepR), Janus kinase2 (Jak2), signal transducer and activator of transcription 3 (Stat3), suppressor of cytokine signaling-3 (Socs3), angiotensin II receptor type 1 (AT1), angiotensin II receptor type 2 (AT2), phosphatidylinositol 3 kinase (P13K), serine threonine kinase (Akt), nuclear factor of kappa B (NF-&kappa;Bp65), inhibitor of nuclear factor kappa-B kinase α (IKKα), NF-kappa-B inhibitor β (lKKβ), NF-kappa-B inhibitor α (IKBα), and AMP-activated protein kinase (AMPK) were detected by quantitative real-time PCR (qPCR). Expression levels of AT1 and LepR in aorta were detected by immunohistochemical assay and Western blot respectively.

<b>RESULTSb>Compared with the control group, BW, BP, and blood lipids increased; serum levels of leptin (Lep) , Ang II, Hcy, ET-1, TNF-α, IL-6, and p2-MG increased, but NO decreased in the model group (P < 0.05, P < 0.01). Aortal endothelial injury and smooth muscle cell proliferation occurred in the model group, accompanied with heart and renal injury. Compared with the control group, mRNA expression levels of LepR, Jak2, Stat3, Socs3, AT1 , PI3K, Akt, NF-&kappa;B p65, IKKβ, IKBα, and AMPK in aorta were up-regulated significantly (P < 0.05), while the expression of IKKa decreased (P < 0.05). Immunohistochem- ical staining showed, brownish yellow deposit of AT1 and LepR was obviously increased, with more extensively positive distribution. Western blot results showed, as compared with the control group, protein expression levels of AT1 and LepR obviously increased in the model group (P < 0.05).

<b>CONCLUSIONSb>Model rats exhibited typical syndromes of EAPDS. They put up weight with fat abdomen, gloomy hair, poor appetite, hypersomnia, lowered activities , reduced food intake, loose stool, dark red tongue, white tongue with white, thick, greasy fur. Lep could be taken as one of objective indicators for evaluating hypertension rat model with EAPDS.

Animals ; Aorta ; Cell Proliferation ; Disease Models, Animal ; Hypertension ; physiopathology ; I-kappa B Proteins ; Interleukin-6 ; Leptin ; blood ; NF-KappaB Inhibitor alpha ; NF-kappa B ; Phosphatidylinositol 3-Kinases ; Rats ; Rats, Wistar ; Suppressor of Cytokine Signaling Proteins ; Transcription Factor RelA ; Tumor Necrosis Factor-alpha

This study aims to investigate the function of two SNPs (rs8904C > T and rs696G >A) in 3' untranslated region (3'UTR) of NFKBIA gene by constructing luciferase reporter gene. A patient's genomic DNA with rs8904 CC and rs696 GA genotype was used as the PCR template. Full-length 3'UTR of NFKBIA gene was amplified by different primers. After sequencing validation, these fragments were inserted to the luciferase reporter vector, pGL3-promoter to construct recombinant plasmids containing four kinds of haplotypes, pGL3-rs8904C/rs696G, pGL3-rs8904C/rs696A, pGL3-rs8904T/rs696G and pGL3-rs8904T/rs696A. Then these plasmids were transfected into LS174T cells and the luciferase activity was detected. Compared with pGL3-vector transfected cells (negative control), the luciferase activity of the four kinds of recombinant plasmids was significantly decreased (P < 0.001). For rs696G > A, the luciferase activity of the recombinant plasmids containing A allele (pGL3-rs8904C/rs696A and pGL3-rs8904T/rs696A) was about 45.1% (P < 0.05) and 56.1% (P < 0.001) lower than those containing G allele (pGL3-rs8904C/rs696G and pGL3-rs8904T/rs696G), respectively. For rs8904C > T, there were no significant differences in the luciferase activity between the recombinant plasmids containing T allele and those with C allele. Together, the luciferase reporter gene vectors containing SNPs in NFKBIA gene 3'UTR were constructed successfully and rs696G > A could decrease the luciferase activity while rs8904C >T didn't have much effect on the luciferase activity.
3' Untranslated Regions ; Genes, Reporter ; Genetic Vectors ; Humans ; I-kappa B Proteins ; genetics ; Luciferases ; NF-KappaB Inhibitor alpha ; Plasmids ; Polymorphism, Single Nucleotide ; Promoter Regions, Genetic ; Transfection

<b>OBJECTIVEb>To examine the mechanism underlying the beneficial role of cinnamaldehyde on oxidative damage and apoptosis in high glucose (HG)-induced dorsal root ganglion (DRG) neurons in vitro.

<b>METHODSb>HG-treated DRG neurons were developed as an in vitro model of diabetic neuropathy. The neurons were randomly divided into five groups: the control group, the HG group and the HG groups treated with 25, 50 and 100 nmol/L cinnamaldehyde, respectively. Cell viability was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and apoptosis rate was evaluated by the in situ TdT-mediated dUTP nick end labeling (TUNEL) assay. The intracellular level of reactive oxygen species (ROS) was measured with flow cytometry. Expression of nuclear factor-kappa B (NF-&kappa;B), inhibitor of &kappa;B (I&kappa;B), phosphorylated I&kappa;B (p-I&kappa;B), tumor necrosis factor (TNF)-α, interleukin-6 (IL-6) and caspase-3 were determined by western blotting and real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). Expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase-1 (HO-1) were also measured by western blotting.

<b>RESULTSb>Cinnamaldehyde reduced HG-induced loss of viability, apoptosis and intracellular generation of ROS in the DRG neurons via inhibiting NF-&kappa;B activity. The western blot assay results showed that the HG-induced elevated expressions of NF-&kappa;B, I&kappa;B and p-I&kappa;B were remarkably reduced by cinnamaldehyde treatment in a dose-dependent manner (P <0.01). The HG-induced over-expression of NF-&kappa;B p65 mRNA was remarkably attenuated after cinnamaldehyde treatment in a dose-dependent manner (P <0.01). However, the expressions of Nrf2 and HO-1 were not upregulated. Treatment with cinnamaldehyde not only attenuated caspase-3 activation and the caspase cleavage cascade in DRG neurons, but also lowered the elevated IL-6, TNF-α, cyclo-oxygenase and inducible nitric oxide synthase levels, indicating a reduction in inflammatory damage.

<b>CONCLUSIONSb>Cinnamaldehyde protected DRG neurons from the deleterious effects of HG through inactivation of NF-&kappa;B pathway but not through activation of Nrf2/HO-1. And thus cinnamaldehyde may have potential application as a treatment for DPN.

Acrolein ; administration & dosage ; analogs & derivatives ; pharmacology ; Animals ; Anti-Inflammatory Agents ; pharmacology ; Apoptosis ; drug effects ; Blotting, Western ; Caspase 3 ; metabolism ; Cell Survival ; drug effects ; Cells, Cultured ; Ganglia, Spinal ; drug effects ; metabolism ; pathology ; Glucose ; toxicity ; Heme Oxygenase (Decyclizing) ; metabolism ; I-kappa B Proteins ; metabolism ; Interleukin-6 ; metabolism ; NF-E2-Related Factor 2 ; metabolism ; NF-kappa B ; metabolism ; Neurons ; drug effects ; metabolism ; pathology ; Neuroprotective Agents ; pharmacology ; Oxidation-Reduction ; drug effects ; Phosphorylation ; drug effects ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism