Isoorientin reverses lung cancer drug resistance by promoting ferroptosis via the SIRT6/Nrf2/GPX4 signaling pathway.

Cisplatin, or DDP, is a highly successful and well-known chemotherapy drug used to treat cancer. Acquired resistance to chemotherapy is a major clinical concern, yet the mechanisms of this resistance are still unknown. Ferroptosis is a type of cell death distinct from other forms, fueled by a buildup of iron-associated lipid reactive oxygen species (ROS). Gaining insight into the process of ferroptosis could lead to novel treatments for overcoming cancer resistance. In this study, the combination of isoorientin (IO) and DDP treatment resulted in a significant decrease in the viability of drug-resistant cells, a substantial increase in intracellular iron, malondialdehyde (MDA) and ROS concentrations, a notable decrease in glutathione concentration, and the occurrence of ferroptosis in cells, as revealed by in vitro and in vivo experiments. Additionally, there was a decrease in the expression of nuclear factor-erythroid factor 2-related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4), and sirtuin 6 (SIRT6) proteins, and an increase in cellular ferroptosis. Isoorientin acts as a mediator to regulate cellular ferroptosis and reverse drug resistance in lung cancer cells by controlling the SIRT6/Nrf2/GPX4 signaling pathway. The findings of this study suggest that IO can promote ferroptosis and reverse drug resistance in lung cancer through the SIRT6/Nrf2/GPX4 signaling pathway, thus offering a theoretical basis for its potential clinical application.

Evaluation of potential drug interactions of oral anticoagulants in outpatients based on pharmacy information databases

The interactions between hypoglycemic drugs and other drugs were retrieved based on the pharmacy information database to evaluate the X-level/contraindication and D-level/serious potential drug interactions (pDDIs) of outpatient anticoagulant prescriptions, so as to provide a guarantee for clinically safe drug use. METHODS: Based on the interaction of 5 oral anticoagulants recommended in the "China Guidelines for the Prevention and Treatment of Thrombotic Diseases (2018 Edition)" retrieved from the two databases of Lexicomp and Micromedex, statistics of a hospital from January 1,2021 to 2022 During March 31st,200 outpatients with anticoagulant prescriptions for grade X/contraindication and grade D/severe pDDIs were analyzed by multivariate Logistic binary regression analysis. RESULTS: Among the 200 athletic patients, there were 0 pairs of grade X/taboo pDDIs,and 67 pairs of grade D/severe pDDIs, mainly due to grade D/serious potential bleeding caused by the combination of anticoagulants and non-steroidal anti-inflammatory drugs(NSAIDs) risk. Multivariate Logistic binary regression analysis found that multiple drug combination (≥5 kinds) and concomitant cardiovascular disease were risk factors for the occurrence of grade D/severe pDDIs. CONCLUSION: for athletic patients with multiple diseases coexisting and needing to take multiple drugs, it is necessary to pay attention to the pDDIs of anticoagulant drugs, select appropriate drugs, and avoid fatal risks such as severe bleeding. Adverse reactions after medication were closely monitored. (AU)

Ferulic acid alleviates high fat diet-induced cognitive impairment by inhibiting oxidative stress and apoptosis.

Cognitive impairment has become a major public health problem. Growing evidence suggests that high-fat diet (HFD) can cause cognitive dysfunction and increase the risk of dementia. However, effective treatment for cognitive impairment is not available. Ferulic acid (FA) is a single phenolic compound with anti-inflammatory and antioxidant properties. Nevertheless, its role in regulating learning and memory in HFD-fed mice and the underlying mechanism remains unclear. In this study, we aimed to identify the neuroprotective mechanisms of FA in HFD induced cognitive impairment. We found that FA improved the survival rate of HT22 cells treated with palmitic acid (PA), inhibited cell apoptosis, and reduced oxidative stress via the IRS1/PI3K/AKT/GSK3ß signaling pathway; Furthermore, FA treatment for 24 weeks improved the learning and memory of HFD-fed mice and decreased hyperlipidemia. Moreover, the expression of Nrf2 and Gpx4 proteins were decreased in HFD-fed mice. After FA treatment, the decline of these proteins was reversed. Our study showed that the neuroprotective effect of FA on cognitive impairment was related to the inhibition of oxidative stress and apoptosis and regulation of glucose and lipid metabolism. These findings suggested that FA can be developed as a potential agent for the treatment of HFD-induced cognitive impairment.

Embedding evidence of early postoperative off-bed activities and rehabilitation in a real clinical setting in China: an interrupted time-series study.

BACKGROUND: Patients should be encouraged to mobilize with 24 h of caesarean section. However, the time of the first off-bed activity after surgery is usually 24 ~ 48 h in China. Due to the lack of knowledge of early off-bed activities, lack of attention to medical pain, and the absence of systematic evidence for the clinical transformation process. the aim of this study was showed that the application of evidence needs to be embedding in the real setting to construct the localization plan and achieve the effective result. METHODS: To establish evidence of the benefits of early postoperative off-bed activities on patients' well-being based on a literature review. An interrupted time series analysis was used to evaluate the effectiveness of the intervention. The first and third periods were both five months (from February 1st, 2019 to January 31st, 2020), with a two-month interrupted time (from July 1st, 2019 to August 31st, 2019). RESULTS: Eight clinical practices were retrieved from the literature and incorporated into the intervention. A total of 465 patients were included: 226 patients before and 239 patients after implementing the intervention. The average onset time of postoperative off-bed activities was significantly earlier after the intervention than before the intervention (20.01 vs. 31.89 h after the operation, P < 0.001). The 24-h off-bed rate increased from 30.94% before to 91.21% after the intervention (P < 0.001). The average pain score of patients decreased from 5.23 points before to 3.82 points after the intervention (P = 0.032). The average postoperative hospital stay was shortened from 5.06 days before to 3.51 days after the intervention (P < 0.001). In addition, the incidence rates of postoperative ileus (POI) and infection decreased from 5.38% and 2.65% before to 1.67% and 0.84% after the intervention, respectively (P < 0.001). CONCLUSIONS: We established an evidence-based nursing intervention. Evaluation of the effect of evidence-based practices should be considered in the clinical setting and include preoperative health education, effective analgesia management, and safety management.

Nifedipine or amlodipine? The choice for hypertension during pregnancy: a systematic review and meta-analysis.

BACKGROUND: There is a lack of sufficient evidence regarding efficacy and safety of amlodipine on treating hypertension during pregnancy. OBJECTIVE: To compare antihypertensive efficacy, pregnancy outcome and safety of amlodipine with nifedipine on hypertension during pregnancy. METHODS: A systematic search of PubMed, Embase, Cochrane Library, clinicaltrials.gov, Chinese National Knowledge Infrastructure, Wanfang Database and China Biology Medicine disc of randomized controlled trials (RCTs) up to April l5, 2021 was conducted on RCTs comparing amlodipine to nifedipine for the treatment of hypertension during pregnancy. Screening, data extraction, and quality assessment were done by two independent reviewers. To estimate relative effects from all available evidence, a meta-analysis was conducted. RESULTS: Seventeen RCTs were included. Amlodipine was found the efficacy is slightly superior to nifedipine on treating hypertension during pregnancy (RR 1.06, 95% CI 1.01 to 1.10) with a decreased risk for maternal side effects (RR 0.42, 95% CI 0.29 to 0.61). Subgroup analysis found amlodipine can get a better control on SBP (RR - 11.68, 95% CI - 17.98 to - 5.37) and DBP (RR - 7.44, 95% CI - 13.81 to - 1.06) compared with intermediate-/long-acting nifedipine. In addition, there was no difference between amlodipine and nifedipine on pregnancy outcomes including caesarean section, premature labour, placental abruption, FGR, fetal distress, neonatal asphyxia. CONCLUSIONS: Given the results of this systematic review and meta-analysis, amlodipine can be effectively and safely used for hypertension during pregnancy.

Huperzine A protects against traumatic brain injury through anti-oxidative effects via the Nrf2-ARE pathway.

OBJECTIVES: Traumatic brain injury (TBI) is a prominent health problem worldwide and it may lead to cognitive dysfunction, disability, and even death. To date, there is no effective treatment for TBI. Our previous study showed that Huperzine A (HupA) improved cognitive function in a mouse model of TBI. However, the detailed mechanism of HupA remains unaddressed. In this study, we investigated the possible mechanism of the neuroprotective effect of HupA. MATERIALS AND METHODS: C57BL/6 mice were randomly divided into 3 groups as sham, injured with vehicle treatment, and injured with HupA treatment groups. The Morris water maze task was used to evaluate the impairment of special learning and memory. Brain edema was as-sessed by measuring the wet weight to dry weight ratio. Malondialdehyde (MDA) and glutathione peroxidase (GPx) levels were measured for oxidative stress. Protein expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygen-ase-1(HO-1), and synaptophysin were detected by Western blot. The brain sections were stained with hematoxylin-eosin (H&E) for histology study. RESULTS: We found that HupA therapy improved histology and cognitive functional outcomes after TBI. HupA reduced brain edema in TBI mice. furthermore, HupA inhibited ox-idative stress. HupA promoted nuclear factor erythroid 2-related factor 2 (Nrf2) nu-clear translocation and activated Nrf2 after TBI. CONCLUSION: HupA protects against TBI through antioxidative effects via the Nrf2-ARE pathway.

Knockdown of zinc transporter ZIP8 expression inhibits neuroblastoma progression and metastasis in vitro.

Neuroblastoma is one of the leading causes of cancer­associated mortality worldwide, particularly in children, partially due to the absence of effective therapeutic targets and diagnostic biomarkers. Therefore, novel molecular targets are critical to the development of therapeutic approaches for neuroblastoma. In the present study, the functions of zinc transporter ZIP8 (Zip8), a member of the zinc transporting protein family, were investigated as novel molecular targets in neuroblastoma cancer cells. The proliferation rates of neuroblastoma cancer cells were significantly decreased when Zip8 was knocked down by lentiviral­mediated RNA interference. Study of the molecular mechanism suggested that Zip8 modulated the expression of key genes involved in the nuclear factor­κB signaling pathway. Furthermore, Zip8 depletion suppressed the migratory potential of neuroblastoma cancer cells by reducing the expression levels of matrix metalloproteinases. In conclusion, the results of the present study suggested that Zip8 was an important regulator of neuroblastoma cell proliferation and migration, indicating that Zip8 may be a potential anticancer therapeutic target and a promising diagnostic biomarker for human neuroblastoma.

Memantine improves outcomes after repetitive traumatic brain injury.

Repetitive mild traumatic brain injury (rmTBI; e.g., sports concussions) is common and results in significant cognitive impairment. Targeted therapies for rmTBI are lacking, though evidence from other injury models indicates that targeting N-methyl-d-aspartate (NMDA) receptor (NMDAR)-mediated glutamatergic toxicity might mitigate rmTBI-induced neurologic deficits. However, there is a paucity of preclinical or clinical data regarding NMDAR antagonist efficacy in the rmTBI setting. To test whether NMDAR antagonist therapy improves outcomes after rmTBI, mice were subjected to rmTBI injury (4 injuries in 4days) and randomized to treatment with the NMDA antagonist memantine or with vehicle. Functional outcomes were assessed by motor, anxiety/impulsivity and mnemonic behavioral tests. At the synaptic level, NMDAR-dependent long-term potentiation (LTP) was assessed in isolated neocortical slices. At the molecular level, the magnitude of gliosis and tau hyper-phosphorylation was tested by Western blot and immunostaining, and NMDAR subunit expression was evaluated by Western blot and polymerase chain reaction (PCR). Compared to vehicle-treated mice, memantine-treated mice had reduced tau phosphorylation at acute time points after injury, and less glial activation and LTP deficit 1 month after injury. Treatment with memantine also corresponded to normal NMDAR expression after rmTBI. No corresponding protection in behavior outcomes was observed. Here we found NMDAR antagonist therapy may improve histopathological and functional outcomes after rmTBI, though without consistent corresponding improvement in behavioral outcomes. These data raise prospects for therapeutic post-concussive NMDAR antagonism, particularly in athletes and warriors, who suffer functional impairment and neurodegenerative sequelae after multiple concussions.

Huperzine A alleviates neuroinflammation, oxidative stress and improves cognitive function after repetitive traumatic brain injury.

Traumatic brain injury (TBI) may trigger secondary injury cascades including endoplasmic reticulum stress, oxidative stress, and neuroinflammation. Unfortunately, there are no effective treatments targeting either primary or secondary injuries that result in long-term detrimental consequences. Huperzine A (HupA) is a potent acetylcholinesterase inhibitor (AChEI) that has been used treatment of Alzheimer's disease (AD). This study aimed to explore the neuroprotective effects of HupA in TBI and its possible mechanisms. Repetitive mild closed head injury (CHI) model was used to mimic concussive TBI. Mice were randomly assigned into three groups including sham, vehicle-treated and HupA-treated injured mice. The HupA was given at dose of 1.0 mg/kg/day and was initiated 30 min after the first injury, then administered daily for a total of 30 days. The neuronal functions including motor functions, emotion-like behaviors, learning and memory were tested. Axonal injury, reactive oxygen species (ROS), and neuroinflammation were examined as well. The results showed that injured mice treated with HupA had significant improvement in Morris water maze performance compared with vehicle-treated injured mice. HupA treatment significantly attenuated markers of neuroinflammation and oxidative stress in the injured mice. Taken together, HupA was effective in reducing neuroinflammation, oxidative stress and behavioral recovery after TBI. HupA is a promising candidate for treatment of TBI.

Adolescent Mice Demonstrate a Distinct Pattern of Injury after Repetitive Mild Traumatic Brain Injury.

Recently, there has been increasing interest in outcomes after repetitive mild traumatic brain injury (rmTBI) (e.g., sports concussions). Although most of the scientific attention has focused on elite athlete populations, the sequelae of rmTBI in children and young adults have not been well studied. Prior TBI studies have suggested that developmental differences in response to injury, including differences in excitotoxicity and inflammation, could result in differences in functional and histopathological outcomes after injury. The purpose of this study is to compare outcomes in adolescent (5-week-old) versus adult (4-month-old) mice in a clinically relevant model of rmTBI. We hypothesized that functional and histopathological outcomes after rmTBI would differ in developing adolescent brains compared with mature adult brains. Male adolescent and adult (C57Bl/6) mice were subjected to a weight drop model of rmTBI (n = 10-16/group). Loss of consciousness (LOC) after each injury was measured. Functional outcomes were assessed including tests of balance (rotorod), spatial memory (Morris water maze), and impulsivity (elevated plus maze). After behavioral testing, brains were assessed for histopathological outcomes including microglial immunolabeling and N-methyl-d-aspartate (NMDA) receptor subunit expression. Injured adolescent mice had longer LOC than injured adult mice compared with their respective sham controls. Compared with sham mice, adolescent and adult mice subjected to rmTBI had impaired balance, increased impulsivity, and worse spatial memory that persisted up to 3 months after injury, and the effect of injury was worse in adolescent than in adult mice in terms of spatial memory. Three months after injury, adolescent and adult mice demonstrated increased ionized calcium binding adaptor 1 (IbA1) immunolabeling compared with sham controls. Compared with sham controls, NMDA receptor subtype 2B (NR2B) expression in the hippocampus was reduced by ∼20% in both adolescent and adult injured mice. The data suggest that injured adolescent mice may show a distinct pattern of functional deficits after injury that warrants further mechanistic studies.

[Puerarin alleviates cognitive impairment and tau hyperphosphorylation in APP/PS1 transgenic mice].

To observe the effect of puerarin on learning and memory function and tau phosphorylation in APP/PS1 transgenic mice, drugs were administered to 3-month old APP/PS1 transgenic mice. Learning and memory function of mice were assessed by Morris water maze test 3 months after treatment. Animals were decapitated after behavioral test. The levels of Aß were detected by ELISA, the expression of protein [tau, phosphorylated tau, GSK3ß and p-GSK3ß(Ser9)] were assessed by Western blot. Morris water maze test showed that the escape latency of APP/PS1 double transgenic mice was significantly longer than that of the normal control group, and the residence time of the original quadrant was significantly shorter. The escape latency of puerarin group was significantly shorter and the residence time of the original quadrant was prolonged compared with the model group. Compared with the normal control group, the levels of Aß in the cortex of APP/PS1 transgenic mice were increased, the expression of phosphorylated tau was significantly increased, and the expression of phosphorylated GSK3ß(Ser9) protein was decreased. Treatment with puerarin, the latency of APP/PS1 transgenic mice was significantly reduced, the level of Aß was decreased, the expression of phosphorylated tau was significantly decreased, and the expression of phosphorylated GSK3ß(Ser9) protein was increased. Puerarin improves the learning and memory impairment by reducing the formation of Aß, activating the GSK3ß signaling pathway, inhibiting the phosphorylation of tau in APP/PS1 double transgenic mice.

Transcriptional regulation of BACE1 by NFAT3 leads to enhanced amyloidogenic processing.

Deposition of amyloid ß (Aß) to form neuritic plaques in the brain is the pathological hallmark of Alzheimer's disease (AD). Aß is generated from sequential cleavages of the ß-amyloid precursor protein (APP) by the ß- and γ-secretases, and ß-site APP-cleaving enzyme 1 (BACE1) is the essential ß-secretase for Aß generation. Vulnerable regions in AD brains show increased BACE1 protein levels. However, the underlying mechanism how BACE1 is regulated remains to be further illustrated. Nuclear Factor of Activated T-cells (NFAT) has been implicated in AD pathogenesis. Despite the increasing appreciation for the importance of NFAT-dependent transcription in the nervous system, the regulation and function of specific NFAT isoforms in neurons is poorly understood. In this report we found that both BACE1 and NFAT3 levels were significantly increased in the brains of APP/PS1 transgenic mice. We found that overexpression of NFAT3 resulted in increase of BACE1 promoter activity and BACE1 transcription, while disruption of NFAT3 expression decreased BACE1 gene transcription and protein expression in SAS1 cells. In a addition, overexpression of NFAT3 leads to increase levels of Aß production. Chromatin immunoprecipitation analysis revealed direct binding of NFAT3 to specific DNA sequences within BACE1 promoter region. Taken together, our results indicate that NFAT is a BACE1 transcription factor. Our study suggests that inhibition of NFAT-mediated BACE1 expression may be a valuable drug target for AD therapy.

Tacrine-6-ferulic acid, a novel multifunctional dimer, inhibits amyloid-ß-mediated Alzheimer's disease-associated pathogenesis in vitro and in vivo.

We have previously synthesized a series of hybrid compounds by linking ferulic acid to tacrine as multifunctional agents based on the hypotheses that Alzheimer's disease (AD) generates cholinergic deficiency and oxidative stress. Interestingly, we found that they may have potential pharmacological activities for treating AD. Here we report for the first time that tacrine-6-ferulic acid (T6FA), one of these compounds, can prevent amyloid-ß peptide (Aß)-induced AD-associated pathological changes in vitro and in vivo. Our results showed that T6FA significantly inhibited auto- and acetylcholinesterase (AChE)-induced aggregation of Aß(1-40)in vitro and blocked the cell death induced by Aß(1-40) in PC12 cells. In an AD mouse model by the intracerebroventricular injection of Aß(1-40), T6FA significantly improved the cognitive ability along with increasing choline acetyltransferase and superoxide dismutase activity, decreasing AChE activity and malondialdehyde level. Based on our findings, we conclude that T6FA may be a promising multifunctional drug candidate for AD.

HIV-infection resistance in PMBC-derived dendritic cells modified with recombinant virus.

This study aimed to identify the characteristics of recombinant-adenovirus-modified PBMC-derived dendritic cells and their resistance to HIV-1 infection by integrating the CCR5∆32, CCR5siRNA, HIV-1 pol and HIV-1 int genes into a recombinant adenovirus vector using the AdEasy system. Dendritic cells (DCs) were isolated from human PBMCs from blood of healthy donors. The expression of CCR5∆32, CCR5, CXCR4 and HIV-1 p24 in PBMCs or modified cells was measured by western blot, p24 expression in cell lysates was measured by ELISA, and HIV-1 entry was measured by ß-galactosidase assay. Furthermore, T-cell immunity induced by the recombinant adenovirus was measured by ELISPOT assay. After the cells were modified by Ad-R5∆32siRNA, the expression of CCR5∆32 increased, while the expression of CCR5 and CXCR4 decreased. There was no adverse effect of adenoviral gene transfer on DC development. CD83 expression on the surface of mature DCs did not change after gene transfer. The expression of p24 remained at low levels in modified cells when challenged by HIV-1. The modified cells showed resistance to HIV-1 infection. Results indicated that recombinant-adenovirus-modified cells demonstrated good resistance to HIV-1 infection. Modification of HSC-derived immune cells, such as DCs, may be a potent strategy to resist HIV-1 infection.

Cryptotanshinione inhibits ß-amyloid aggregation and protects damage from ß-amyloid in SH-SY5Y cells.

The deposition of amyloid ß-protein (Aß) fibrils into plaques within the brain parenchyma and along cerebral blood vessels is a hallmark of Alzheimer's disease (AD). Aß42 oligomers and fibrils cause the breakdown of neural circuits, neuronal death and eventually dementia. Drugs that inhibit Aß42 aggregation may be a novel direction in AD drug discovery. Cryptotanshinone (CTS), an active component of the medicinal herb Salvia miltiorrhiza, has been shown to improve learning and memory in several pharmacological models of AD. However, the effects of CTS on the Aß aggregation and toxicity are unclear. The current work shows the effectiveness of CTS on the inhibition of Aß42 aggregation and toxicity to human neuroblastoma cells. In this study, we demonstrated that CTS can inhibit Aß42 spontaneous aggregation using thioflavin T fluorescence assay and transmission electron microscopy. Furthermore, we investigated the effects of CTS on Aß-induced oxidative cell death in cultured SH-SY5Y cells. MTT and lactate dehydrogenase assays showed that CTS reduced the cytotoxicity induced by Aß42. CTS also dramatically reduced Aß42-induced cellular apoptosis and increased level of reactive oxygen species in these cells. Our study suggests that CTS may be useful in the inhibition or prevention of AD development and progression.

Biological characteristics of foam cell formation in smooth muscle cells derived from bone marrow stem cells.

Bone marrow mesenchymal stem cells (BMSC) can differentiate into diverse cell types, including adipogenic, osteogenic, chondrogenic and myogenic lineages. There are lots of BMSC accumulated in atherosclerosis vessels and differentiate into VSMC. However, it is unclear whether VSMC originated from BMSC (BMSC-SMC) could remodel the vessel in new tunica intima or promote the pathogenesis of atherosclerosis. In this study, BMSC were differentiated into VSMC in response to the transforming growth factor ß (TGF-ß) and shown to express a number of VSMC markers, such as α-smooth muscle actin (α-SMA) and smooth muscle myosin heavy chain1 (SM-MHC1). BMSC-SMC became foam cells after treatment with 80 mg/L ox-LDL for 72 hours. Ox-LDL could upregulate scavenger receptor class A (SR-A) but downregulate the ATP-binding cassette transporter A1 (ABCA1) and caveolin-1 protein expression, suggesting that modulating relative protein activity contributes to smooth muscle foam cell formation in BMSC-SMC. Furthermore, we found that BMSC-SMC have some biological characteristics that are similar to VSMC, such as the ability of proliferation and secretion of extracellular matrix, but, at the same time, retain some biological characteristics of BMSC, such as a high level of migration. These results suggest that BMSC-SMC could be induced to foam cells and be involved in the development of atherosclerosis.

Cryptotanshinione upregulates alpha-secretase by activation PI3K pathway in cortical neurons.

The amyloid precursor protein (APP) is cleaved enzymatically by nonamyloidogenic and amyloidogenic pathways. alpha-Secretase cleaves APP within beta amyloid protein (Abeta) sequence, resulting in the release of a secreted fragment of APP (sAPPalpha) and precluding Abeta generation. Cryptotanshinone (CTS), an active component of the medicinal herb Salvia miltiorrhiza, has been shown to improve learning and memory in several pharmacological models of Alzheimer's disease (AD). We have shown previously that CTS modulated APP metabolism by elevation alpha-secretase activity. However, the molecular mechanisms involved were unclear. Here we reported that CTS increased alpha-secretase activity and sAPPalpha release. To gain insight into the molecular mechanism whereby CTS modulates alpha-secretase, we evaluated the involvement of three candidate alpha-secretase enzymes, a-disintegrin and metalloprotease (ADAM) 9, 10, or 17, in CTS-induced non-amyloidogenic APP metabolism. Results showed that CTS treatment of cortical neurons overexpressing Swedish mutant human APP695 markedly elevated ADAM10 protein, and the inhibitor of ADAM10 inhibited the CTS-induced increase in alpha-secretase activity, suggesting CTS modulated alpha-secretase activity by upregulation ADAM10 protein. By using several specific protein kinase inhibitors, we showed that phosphatidylinositol 3-kinase (PI3K) mediated the CTS-induced alpha-secretase activation.

[Mechanisms of foam cell formation in smooth muscle cell derived from bone marrow stem cells].

OBJECTIVE: To establish a model of smooth muscle cells differentiated from bone mesenchymal stem cells (BMSC-SMCs) in vitro and explore the relationship between scavenger receptors A (SR-A) and caveolin-1. METHODS: BMSCs were isolated from the femoral bone of SD rats by adherent culture. After treatment of the BMSC-SMCs with 80 mg/L ox-LDL for 72 h, Western blotting was performed to detect the expression of scavenger receptor SR-A, cell cholesterol transport protein ATP-binding cassette transporter Al (ABCA1) and caveolin-1. RESULTS: BMCS-SMCs became foam cells after treatment with ox-LDL. BMSC-SMC gave rise to more foam cell formation than VSMCs did. Western blotting showed that treatment with 80 mg/L ox-LDL for 72 h resulted in significantly increased expression of SR-A and significantly decreased expressions of ABCA1 and caveolin-1. CONCLUSIONS: Treatment of BMCS-SMCs with ox-LDL results in cholesterol ester accumulation in the cells to result in foam cells, the mechanism of which involves up-regulation of scavenger receptor SR-A expression and down-regulation of the reverse cholesterol transport protein ABCA1 and caveolin-1 expression.

[Effect of oxidative low-density lipoprotein on the proliferation of bone marrow stem cell- derived smooth muscle cells].

OBJECTIVE: To establish the model of bone mesenchymal stem cell-derived smooth muscle cells (BMSC-SMCs) and investigate the role of BMSC-SMCs in the development and progression of artherosclerosis. METHODS: BMSCs were isolated from the femoral bone of SD rats by adherent tissue culture method, and vascular smooth muscle cells (VSMCs) were obtained from the thoracic aorta. The differentiation of BMSCs into BMSC-SMCs was induced in the conditioned medium. The specific markers of BMSCs and BMSC-SMCs were identified by immunofluorescence (IF) staining. After treatment with 80 mg/L oxidative low-density lipoprotein (ox-LDL) for 72 h, the growth characteristics of BMSC-SMCs and VSMCs were observed. Flow cytometry was applied to analyze the cell cycle of BMSC-SMCs and VSMCs. RESULTS: BMCS-SMCs transformed into foam cells after treatment with ox-LDL, which was more obvious in comparison with VSMCs. The growth curve of BMSC-SMCs and VSMCs presented with an S-shape pattern with the cell doubling time of 20 and 32 h, which was reduced to 15 and 28 h after treatment with 80 mg/L ox-LDL, respectively. Flow cytometry showed that exposure to 80 mg/L ox-LDL significantly increased G(0)/G(1) and decreased S and G(2)/M phase cells in both BMSC-SMCs (P<0.01, n=3) and VSMCs (P<0.05, n=3) in comparison with the control cells. CONCLUSION: BMSC-SMC might be involved in the formation of fatty core and accelerate the development of atherosclerosis.

A synthetic peptide derived from A1 module in CRD4 of human TNF receptor-1 inhibits binding and proinflammatory effect of human TNF-alpha.

Tumour necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine, which has been shown to be a causative factor in rheumatoid arthritis, inflammatory bowel disease and septic shock. Proinflammatory effect of TNF-alpha is activated mainly through human TNF receptor-1 (TNF-R1). However, the role of the fourth cystein-rich domain (CRD4) of TNF-R1 extracellular portion in the interaction of TNF-alpha with TNF-R1 is still unclear. In the present study, binding activity of TNF-alpha to TNF-R1 and protein levels of IkappaB-alpha and nuclear transcription factor kappa B (NF-kappaB) p65 subunit in HeLa cells were measured using enzyme-linked immunosorbent assay (ELISA) and western-blot analysis. Pep 3 (LRENECVS) which was derived from the hydrophilic region of A1 module in CRD4 remarkably inhibited the binding of TNF-alpha to TNF-R1, and also reversed TNF-alpha-induced degradation of IkappaB-alpha and nuclear translocation of NF-kappaB p65 subunit in HeLa cells. Our results confirmed that the hydrophilic region of A1 module in CRD4 participated in the interaction of TNF-alpha with TNF-R1, and demonstrated the potential of small-molecule TNF-alpha extracellular inhibitors targeting at A1 module in CRD4 of TNF-R1 in suppressing proinflammatory effect of TNF-alpha.