Resveratrol Promotes Gluconeogenesis by Inhibiting SESN2-mTORC2-AKT Pathway in Calf Hepatocytes.

BACKGROUND: The glucose requirement of dairy cows is mainly met by increasing the rate of hepatic gluconeogenesis. However, due to negative energy balance, the liver of periparturient cows is under oxidative stress induced by lipid over-mobilization, and hepatic gluconeogenesis is reduced. Studies have demonstrated that resveratrol, which is widely known for its antioxidant properties, can alter hepatic gluconeogenesis. However, it is not clear whether resveratrol could regulate hepatic gluconeogenesis by its antioxidant properties. OBJECTIVES: This study aims to investigate the precise effect of resveratrol in hepatic gluconeogenesis, the role of resveratrol on hydrogen peroxide (H2O2)-induced oxidative stress in hepatocytes and the potential mechanism using primary hepatocytes. METHODS: Primary hepatocytes were isolated from 5 healthy Holstein calves (1 d old, 30 to 40 kg, fasted) and treated with different concentrations of resveratrol (0, 5, 10, 25, or 50 µM) combined with or without H2O2 (0, 100, or 200 µM) induction for 12 h. RESULTS: Resveratrol enhanced the expression of gluconeogenic genes of calf hepatocytes in a dose-dependent manner (P < 0.05). Conversely, H2O2 suppressed the expression of gluconeogenic genes and induced oxidative stress (P < 0.05), which was improved by resveratrol in calf hepatocytes (P < 0.001). Furthermore, the mechanistic target of rapamycin complex 2 (mTORC2)-AKT pathway was found to negatively regulate gluconeogenesis. An AKT inhibitor was used to assess the role of the mTORC2-AKT pathway in the effects of resveratrol. The results showed resveratrol promoted hepatic gluconeogenesis by inhibiting the mTORC2-AKT pathway. Moreover, sestrin 2 (SESN2) upregulated the activity of mTORC2. We further found that resveratrol decreased SESN2 levels (P < 0.001). CONCLUSIONS: This study indicated that resveratrol enhances the gluconeogenic capacity of calf hepatocytes by improving H2O2-induced oxidative stress and modulating the activity of the SESN2-mTORC2-AKT pathway, implying that resveratrol may be a promising target for ameliorating liver oxidative stress in transition cows.

Butyrate dictates ferroptosis sensitivity through FFAR2-mTOR signaling.

Evidence shows that short-chain fatty acids (SCFAs) play an important role in health maintenance and disease development. In particular, butyrate is known to induce apoptosis and autophagy. However, it remains largely unclear whether butyrate can regulate cell ferroptosis, and the mechanism by which has not been studied. In this study, we found that RAS-selective lethal compound 3 (RSL3)- and erastin-induced cell ferroptosis were enhanced by sodium butyrate (NaB). With regard to the underlying mechanism, our results showed that NaB promoted ferroptosis by inducing lipid ROS production via downregulating the expression of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4). Moreover, the FFAR2-AKT-NRF2 axis and FFAR2-mTORC1 axis accounts for the NaB-mediated downregulation of SLC7A11 and GPX4, respectively, in a cAMP-PKA-dependent manner. Functionally, we found that NaB can inhibit tumor growth and the inhibitory effect could be eliminated by administrating MHY1485 (mTORC1 activator) and Ferr-1 (ferroptosis inhibitor). Altogether, in vivo results suggest that NaB treatment is correlated to the mTOR-dependent ferroptosis and consequent tumor growth through xenografts and colitis-associated colorectal tumorigenesis, implicating the potential clinical applications of NaB for future colorectal cancer treatments. Based on all these findings, we have proposed a regulatory mechanism via which butyrate inhibits the mTOR pathway to control ferroptosis and consequent tumorigenesis.

The Relationship Among Nurse Leaders' Humanistic Care Behavior, Nurses' Professional Identity, and Psychological Security.

Objectives: We investigated the relationship among humanistic care behavior, nurses' professional identity, and psychological security among nurse leaders in tertiary hospitals in Beijing, China. Methods: We conducted a cross-sectional survey using convenience sampling to select 1600 clinical nurses from 5 general tertiary hospitals. Participants were surveyed electronically using the Socio-Demographic Profile Questionnaire, the Scale of Humanistic Care Behavior Shown by Nurse Leaders to Nurses, the Nurses' Professional Identity Scale, and the Psychological Security Scale. Results: A total of 1600 questionnaires were distributed, and 1526 valid questionnaires were collected. There was a significant positive correlation between nurse leaders' humanistic care behavior and nurses' professional identity (r=0.66, p<.001). There was also a significant positive correlation between nurse leaders' humanistic care behavior and psychological security (r=0.45, p<.001) and between psychological security and nurses' professional identity (r=0.64, p<.001). A multiple regression analysis showed that the humanistic care behavior of nurse leaders and the psychological security of nurses influenced nurses' professional identity. Structural equation modelling analysis showed that psychological security played a mediating role in the humanistic care behavior of nurses and nurses' professional identity (ß=0.210, p<.001). Conclusions: The humanistic care behavior of nurse leaders significantly affects nurses' professional identity and psychological security scores. Nurse leaders' humanistic care can also indirectly affect professional identity through psychological security as a mediator; therefore, in nursing management, improving nurse leaders' humanistic care behavior can improve nurses' professional identity.

Role of FLCN Phosphorylation in Insulin-Mediated mTORC1 Activation and Tumorigenesis.

The amino acid-stimulated Rag GTPase pathway is one of the main pathways that regulate mechanistic target of rapamycin complex 1 (mTORC1) activation and function, but little is known about the effects of growth factors on Rag GTPase-mediated mTORC1 activation. Here, a highly conserved insulin-responsive phosphorylation site on folliculin (FLCN), Ser62, that is phosphorylates by AKT1 is identified and characterized. mTORC2-AKT1 is localized on lysosomes, and RagD-specific recruitment of mTORC2-AKT1 on lysosomes is identified as an essential step in insulin-AKT1-mediated FLCN phosphorylation. Additionally, FLCN phosphorylation inhibits the activity of RagC GTPase and is essential for insulin-induced mTORC1 activation. Functionally, phosphorylated FLCN promotes cell viability and induces autophagy, and also regulates in vivo tumor growth in an mTORC1-dependent manner. Its expression is also positively correlated with mTORC1 activity in colon cancer, clear cell renal cell carcinoma, and chordoma. These results indicate that FLCN is an important intermediate for cross-talk between the amino acid and growth factor pathways. Further, FLCN phosphorylation may be a promising therapeutic target for diseases characterized by mTORC1 dysregulation.

Pharmacological vitamin C inhibits mTOR signaling and tumor growth by degrading Rictor and inducing HMOX1 expression.

Pharmacological vitamin C (VC) is a potential natural compound for cancer treatment. However, the mechanism underlying its antitumor effects remains unclear. In this study, we found that pharmacological VC significantly inhibits the mTOR (including mTORC1 and mTORC2) pathway activation and promotes GSK3-FBXW7-mediated Rictor ubiquitination and degradation by increasing the cellular ROS. Moreover, we identified that HMOX1 is a checkpoint for pharmacological-VC-mediated mTOR inactivation, and the deletion of FBXW7 or HMOX1 suppresses the regulation of pharmacological VC on mTOR activation, cell size, cell viability, and autophagy. More importantly, it was observed that the inhibition of mTOR by pharmacological VC supplementation in vivo produces positive therapeutic responses in tumor growth, while HMOX1 deficiency rescues the inhibitory effect of pharmacological VC on tumor growth. These results demonstrate that VC influences cellular activities and tumor growth by inhibiting the mTOR pathway through Rictor and HMOX1, which may have therapeutic potential for cancer treatment.

Promotion of intestinal epithelial cell apoptosis by enterotoxigenic Escherichia coli via PKA-mediated inhibition of mTORC1 activation.

Enterotoxigenic Escherichia coli (ETEC) is the main causative pathogen of diarrhea. It causes acute watery diarrhea that leads to rapid dehydration and prostration within hours. ETEC is still an important cause of neonatal and post-weaning diarrhea in pigs. However, the mechanism underlying ETEC-induced diarrhea is not yet clear. In this study, we investigated these mechanisms and found that the mTORC1 pathway plays a role in the host response to ETEC F4 infection. Specifically, we found that ETEC F4 treatment significantly repressed mTORC1 activity as well as cell proliferation, promoted apoptosis and regulated the expression of diarrhea-related genes via the promotion of PKA-mediated phosphorylation of SIN1, which plays a critical role in the assembly of mTORC2. These findings indicate that PKA is a checkpoint for ETEC-induced diarrhea. In terms of potential therapeutic strategies, we found that ZnSO4 dramatically rescued ETEC F4-induced the inhibition of mTORC1 activity and cell viability and the induction of apoptosis and alterations in the expression of diarrhea-related genes. Thus, the present findings demonstrate that ETEC F4 influences mTORC1 activation by inhibiting the assembly of mTORC2 through PKA-mediated phosphorylation of SIN1. Further, supplementation with ZnSO4 is an effective strategy for blocking the effect of ETEC F4 on mTORC1 activation, and it may have potential clinical applications in the treatment of ETEC F4-induced diarrhea.

Farnesoid X Receptor (FXR) Regulates mTORC1 Signaling and Autophagy by Inhibiting SESN2 Expression.

SCOPE: The mechanistic target of rapamycin complex 1 (mTORC1), as a link between nutrients and autophagy, senses many nutrients in the microenvironment. A growing body of recent literature describes the function of bile acids (BAs) as versatile signaling molecules, while it remains largely unclear whether mTORC1 can sense BAs and the mechanism has not been studied. METHODS AND RESULTS: After treating LO2 cells with indicated concentration of chenodeoxycholic acid (CDCA) and farnesoid X receptor (FXR) inhibitor/activator for 6 h, it finds that CDCA and FXR significantly accelerate mTORC1 activation. The results of immunofluorescence indicate that CDCA and FXR inhibit cellular autophagy through activating mTORC1 pathway. In particular, these findings show that CDCA and FXR promote the lysosomal translocation and activation of mTORC1 in an amino acid-sensitive manner. Mechanistically, the transcriptomics data indicate that SESN2 is a checkpoint for mTORC1 lysosome translocation and activation induced by FXR, and knockdown SESN2 with siRNA suppresses the regulation of FXR on autophagy. CONCLUSION: These results indicate that FXR-induced decrease in SESN2 expression and activation of the mTORC1 pathway can control autophagy and be explored as potential therapeutic targets for enterohepatic and metabolic disorders.

The mechanistic target of rapamycin complex 1 pathway involved in hepatic gluconeogenesis through peroxisome-proliferator-activated receptor γ coactivator-1α.

Cattle can efficiently perform de novo generation of glucose through hepatic gluconeogenesis to meet post-weaning glucose demand. Substantial evidence points to cattle and non-ruminant animals being characterized by phylogenetic features in terms of their differing capacity for hepatic gluconeogenesis, a process that is highly efficient in cattle yet the underlying mechanism remains unclear. Here we used a variety of transcriptome data, as well as tissue and cell-based methods to uncover the mechanisms of high-efficiency hepatic gluconeogenesis in cattle. We showed that cattle can efficiently convert propionate into pyruvate, at least partly, via high expression of acyl-CoA synthetase short-chain family member 1 (ACSS1), propionyl-CoA carboxylase alpha chain (PCCA), methylmalonyl-CoA epimerase (MCEE), methylmalonyl-CoA mutase (MMUT), and succinate-CoA ligase (SUCLG2) genes in the liver (P < 0.01). Moreover, higher expression of the rate-limiting enzymes of gluconeogenesis, such as phosphoenolpyruvate carboxykinase (PCK) and fructose 1,6-bisphosphatase (FBP), ensures the efficient operation of hepatic gluconeogenesis in cattle (P < 0.01). Mechanistically, we found that cattle liver exhibits highly active mechanistic target of rapamycin complex 1 (mTORC1), and the expressions of PCCA, MMUT, SUCLG2, PCK, and FBP genes are regulated by the activation of mTORC1 (P < 0.001). Finally, our results showed that mTORC1 promotes hepatic gluconeogenesis in a peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) dependent manner. Collectively, our results not only revealed an important mechanism responsible for the quantitative differences in the efficiency of hepatic gluconeogenesis in cattle versus non-ruminant animals, but also established that mTORC1 is indeed involved in the regulation of hepatic gluconeogenesis through PGC-1α. These results provide a novel potential insight into promoting hepatic gluconeogenesis through activated mTORC1 in both ruminants and mammals.

Cystine Induced-mTORC2 Activation through Promoting Sin1 Phosphorylation to Suppress Cancer Cell Ferroptosis.

SCOPE: Mechanistic target of rapamycin (mTOR) serves as a central signaling node in the coordination of cell growth and metabolism, and it functions via two distinct complexes, namely, mTOR complex 1 (mTORC1) and mTORC2. mTORC1 plays a crucial role in sensing amino acids, whereas mTORC2 involves in sensing growth factors. However, it remains largely unclear whether mTORC2 can sense amino acids and the mechanism by which amino acids regulate mTORC2 has not been studied. METHODS AND RESULTS: After treating cells with indicated concentration of amino acids for different time, it is found that the mTORC2 activation is significantly increased in response to amino acids stimulation, especially cystine. Particularly, knockdown solute carrier family 7 member 11 (SLC7A11) by siRNA shows that SLC7A11-mediated cystine uptake is responsible for activating mTORC2. Mechanistically, the study finds that p38 is activated in response to cystine stimulation, and co-immunoprecipitation (Co-IP) experiments suggest that p38 regulates the assembly of components within mTORC2 by mediating the phosphorylation of the mTORC2 subunit mitogen-activated protein kinase-interacting protein 1 (Sin1) in a cystine-dependent manner. Finally, combined with inducers and inhibitors of ferroptosis and cell viability assay, the study observes that cystine-mediated regulation of the p38-Sin1-mTOR-AKT pathway induces resistance to ferroptosis. CONCLUSION: These results indicate that cystine-induced activation of the p38-Sin1-mTORC2-AKT pathway suppresses ferroptosis.

Gap between risk factors and prevention strategies? A nationwide survey of fall prevention among medical and surgical patients.

AIMS: This study aimed to determine the extent to which nurses report assessing evidence-based falls risk factors and implementing targeted prevention for medical and surgical patients in China. DESIGN: This study was a national online survey. METHODS: The respondents were registered nurses working in medical and surgical units in 662 Chinese hospitals. The data concerning the falls risk factor assessments and targeted interventions implemented by nurses were collected online by the Nursing Management Committee of the Chinese Nursing Association in China in 2019. RESULTS: In total, 68 527 valid questionnaires were returned (95.0%). In medical and surgical units, nurses were most likely to report assessing balance, mobility and strength (81.6%) and orthostatic hypotension (76.4%) in falls patients and least likely to report assessing continence (61.3%) and feet and footwear (55.8%). Ensuring the use of appropriate footwear (79.3%) and managing syncope, dizziness and vertigo (73.8%) were the most common multiple interventions, while managing postural hypotension (48.8%) and cognitive impairment (48.4%) was the least common. Nine falls risk factors with clearly matched multifactorial interventions were identified in medical and surgical units (68.2%-97.1%). CONCLUSIONS: The implementation of multifactorial interventions in medical and surgical wards is inconsistent as reported by nurses in medical and surgical wards. Throughout China, nurses are generally concerned about falls risk factors and prevention for their patients; however, limited attention has been focused on continence, feet and footwear assessment and the management of cognitive impairment. Evidence-based falls prevention should be further tailored to the specific risk factors of each patient. IMPACT: Best practice guidelines for falls prevention in hospitals have been developed and published, and it is important for nurses to use these guidelines to guide practice. Our findings identify that in routine care, healthcare providers and hospitals can prevent falls.

T-2 Toxin Induces Ferroptosis by Increasing Lipid Reactive Oxygen Species (ROS) and Downregulating Solute Carrier Family 7 Member 11 (SLC7A11).

T-2 toxin is a trichothecene mycotoxin commonly found in animal feed and agricultural products. Evidence indicates that T-2 toxin induces apoptosis and autophagy. This study investigated the role of ferroptosis in T-2 toxin cytotoxicity. RAS-selective lethal compound 3 (RSL3) and Erastin were applied to initiate ferroptosis. RSL3- and Erastin-initiated cell death were enhanced by T-2 toxin. Treatment with the ferroptosis inhibitor ferrostatin-1 markedly restored the sensitizing effect of T-2 toxin to RSL3- or Erastin-initiated apoptosis, suggesting that ferroptosis plays a vital role in T-2 toxin-induced cytotoxicity. Mechanistically, T-2 toxin promoted ferroptosis by inducing lipid reactive oxygen species (ROS), as N-acetyl-l-cysteine significantly blocked T-2 toxin-induced ferroptosis. Moreover, T-2 toxin decreased the expression of solute carrier family 7 member 11 (SLC7A11) and failed to further enhance ferroptosis in SLC7A11-deficient cells. SLC7A11 overexpression significantly rescued the enhanced ferroptosis caused by T-2 toxin. T-2 toxin induces ferroptosis by downregulating SLC7A11 expression. Ferroptosis mediates T-2 toxin-induced cytotoxicity by increasing ROS and downregulating SLC7A11 expression.

Insulin Injection Knowledge, Attitudes, and Practices of Nurses in China: A Cross-Sectional Nationwide Study.

INTRODUCTION: To evaluate insulin injection knowledge, attitudes, and practices of nurses across China in order to provide reference for the formulation of a national unified standard of insulin injection practice and the targeted implementation of standardized training on insulin injection for nurses. METHODS: We enrolled nurses who worked and injected insulin at grassroot hospitals including community health service centers and township clinics, secondary and tertiary care hospitals across China between July 28, 2019 and August 30, 2019. A nurse insulin injection knowledge, attitude, and practice questionnaire was used to evaluate the knowledge, attitude, and practice level of nurses. RESULTS: A total of 223,368 nurses were included in the study. The mean knowledge score was 13.70 ± 3.30 and 35.19% had a poor knowledge score. The mean attitude score was 17.18 ± 2.69 for the study nurses; merely 3.15% had a poor attitude score. The mean practice score of the study population was 83.03 ± 8.16 and only 0.88% had a poor practice score. Pearson correlation analysis showed significant correlation between the knowledge score and the attitude score (r = 0.29; P < 0.001), the knowledge score and the practice score (r = 0.27; P < 0.001), and between the attitude score and the practice score (r = 0.56; P < 0.001). A multivariate analysis revealed that nurses with higher knowledge scores were also more likely to have higher attitude scores and practice scores, and nurses with higher attitude scores were also more likely to have higher practice scores. CONCLUSION: Chinese nurses have a good attitude and behavior towards insulin injection, while their knowledge of insulin injection is insufficient. It is also revealed that knowledge of insulin injection can directly or indirectly affect insulin injection behavior through attitude, indicating that hospitals should formulate unified insulin injection norms and regularly organize relevant training and assessment so as to improve nurses' knowledge, attitude, and behavior of insulin injection.

Genetic variant of SPARC gene and its association with growth traits in Chinese cattle.

SPARC is a cysteine-rich acidic secreted protein. It is a non-collagen component of bone, which is widely distributed in humans and animals and plays an important role. SPARC has been found in a variety of human cancers (breast cancer, stomach cancer, ovarian cancer, etc.) and diabetes-related research. Especially the muscle and fat metabolism are closely related. In this study, we used a DNA pool to detect a new SNP site (g.12454T  >  C). A total of 616 samples of four breeds of Qinchuan cattle (QC, n = 176 ), Xianan cattle (XN, n = 160 ), Pinan cattle (PN, n = 136 ) and Jiaxian cattle (JX, n = 144 ) were analyzed and identified with ARMS-PCR. In addition, we correlated SNP with growth traits and showed significant correlation with growth traits such as rump length, hip width, and body length ( p < 0.05 ). Moreover, we tested the SPARC gene expression level in different tissues belonging to XN adult cattle ( n = 3 ) and found its high expression in muscle tissues (relative to the kidney). Further, we found the SNP is able to increase the SPARC expression level in skeletal muscle ( n = 12 ). According to statistical data, this SNP site may be applied to a molecular marker of an early marker-assisted selection for early growth of beef cattle.

Ultra-sensitive and plasmon-tunable graphene photodetectors for micro-spectrometry.

We demonstrate an ultra-sensitive photodetector based on a graphene/monolayer MoS2 vertical heterostructure working at room temperature. Highly confined plasmon waves are efficiently excited through a periodic array of monolayer graphene ribbons in which plasmon resonance has remarkably large oscillator strength, resulting in a sharp optical absorption peak in the normal-incidence transmission spectrum. A significant amount of electron-hole pairs are produced in graphene ribbons by optical absorption, separated by the built-in electric field across the graphene/MoS2 heterojunction. The responsivity reaches up to 1 × 107 A W-1 at room temperature due to very strong resonance in the heterostructure, yielding a highly sensitive graphene-based photodetector. Additionally, the absorption can be tuned over a wide spectral range (6-16 µm) by varying gate biasing. The ultra-sensitive, spectrally tunable photodetector could be potentially used as a promising candidate for mid-infrared micro-spectrometers.

Inhibition of angiogenesis by arsenic trioxide via TSP-1-TGF-ß1-CTGF-VEGF functional module in rheumatoid arthritis.

Angiogenesis is a critical factor for rheumatoid arthritis (RA). Although anti-TNF biologics work effectively on some RA patients, concerns have been raised about the possible increased development of malignancies alongside such treatments. Arsenic trioxide (As2O3) has attracted worldwide attention and has been reported to treat some cancers. However, the effects of As2O3 on angiogenesis in the RA synovium remain unclear. Here, we report a systematic increased expression of TSP-1, TGF-ß1, CTGF and VEGF in supernatants of a RA fibroblast-like synoviocytes (RA-FLS) and human dermal microvascular endothelial cells (HDMECs) co-culture compared with those from a normal human fibroblast-like synoviocytes (NH-FLS) and HDMECs co-culture. This increased expression may up-regulate endothelial tube formation and transwell migration, as well as microvessel sprouting in ex vivo aortic ring assay. These networked angiogenic factors mainly form a functional module regulating angiogenesis in the RA synovium. We show that As2O3 inhibits angiogenesis in the collagen-induced arthritis (CIA) synovium and consequently arthritis severity via significant suppression of TSP-1, TGF-ß1, CTGF and VEGF expression in the CIA synovium, plus in the RA-FLS and HDMECs co-culture as well as NH-FLS and HDMECs co-culture system along with the presence or absence of TNF-α treatment. Thus As2O3 has a significant anti-angiogenesis effect on the RA-FLS and CIA synovium via its inhibition of the RA angiogenic functional module of TSP-1, TGF-ß1, CTGF and VEGF and may have a potential for treating RA beyond cancer therapy.

Effects of thapsigargin on the proliferation and survival of human rheumatoid arthritis synovial cells.

A series of experiments have been carried out to investigate the effects of different concentrations of thapsigargin (0, 0.001, 0.1, and 1 µM) on the proliferation and survival of human rheumatoid arthritis synovial cells (MH7A). The results showed that thapsigargin can block the cell proliferation in human rheumatoid arthritis synovial cells in a time- and dose-dependent manner. Results of Hoechst staining suggested that thapsigargin may induce cell apoptosis in MH7A cells in a time- and dose-dependent manner, and the percentages of cell death reached 44.6% at thapsigargin concentration of 1 µM treated for 4 days compared to the control. The protein and mRNA levels of cyclin D1 decreased gradually with the increasing of thapsigargin concentration and treatment times. Moreover, the protein levels of mTORC1 downstream indicators pS6K and p4EBP-1 were reduced by thapsigargin treatment at different concentrations and times, which should be responsible for the reduced cyclin D1 expressions. Our results revealed that thapsigargin may effectively impair the cell proliferation and survival of MH7A cells. The present findings will help to understand the molecular mechanism of fibroblast-like synoviocytes proliferations and suggest that thapsigargin is of potential for the clinical treatment of rheumatoid arthritis.

Arsenic trioxide induces apoptosis of fibroblast-like synoviocytes and represents antiarthritis effect in experimental model of rheumatoid arthritis.

OBJECTIVE: recent studies have demonstrated that rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) proliferate as fiercely as tumor cells. Induction of apoptosis in RA FLS therefore provides a new approach for the inhibition of joint destruction. Arsenic trioxide (As(2)O(3)) was reported to be an effective apoptosis inducer in a variety of cell types. We investigated the possible effect of As(2)O(3) on apoptosis induction of RA FLS and the mechanisms involved in this process. METHODS: apoptosis was determined by flow cytometric analysis, terminal deoxynucleotide transferase-mediated dUTP nick end-labeling, and transmission electron microscopy. The activity and messenger RNA (mRNA) expression of nuclear factor-κB (NF-κB) was then detected by ELISA and real-time polymerase chain reaction, respectively. Activities of caspase-3 and caspase-8 were evaluated using luminogenic substrates. The effect of As(2)O(3) on the morphology of rats with collagen-induced arthritis was evaluated under a light microscope after H&E staining. RESULTS: as(2)O(3) significantly enhanced the apoptosis of RA FLS. It suppressed the DNA-binding activity and mRNA expression level of NF-κB, probably by inhibiting tumor necrosis factor-α-induced activation of NF-κB. As(2)O(3) treatment significantly increased the activity of both caspase-3 and caspase-8. Morphological analysis revealed histological recovery in the synovial membrane. Synovial hyperplasia and inflammation in the joints were effectively inhibited. CONCLUSION: as(2)O(3) represents an apoptotic effect on RA FLS through NF-κB signaling pathway, and this process is mediated by the activation of caspase cascade. Treatment with As(2)O(3) significantly improved the pathologic changes of collagen-induced arthritis and may have potential for treatment of RA.

Daunorubicin induces procoagulant response through phosphatidylserine exposure in red blood cells.

INTRODUCTION: Cytotoxic chemotherapy induces or worsens hemostatic disorders in patients with acute myeloid leukemia. Procoagulant release and tissue factor expression on tumor cells are considered to contribute to chemotherapeutic agents-associated coagulopathy. The role of red blood cells during this process has not been determined; although they lack tissue factor, they may contribute suitable membranes for the amplification phase of blood coagulation. The present study aims to evaluate the possible impact of daunorubicin on phosphatidylserine exposure and consequent procoagulant property of red blood cells. MATERIALS AND METHODS: Red blood cells from acute myeloid leukemia patients and healthy donors were treated with daunorubicin as well as all-trans-retinoic acid, arsenic trioxide or etoposide for 0-48 h. Procoagulant activity was assessed by measurement of a clotting time and by purified coagulation complex assays. Lactadherin was used as a probe for phosphatidylserine. RESULTS: Daunorubicin treatment increased procoagulant activity of red blood cells regardless of the cell origin. Moreover, coagulation complexes assays supported daunorubicin-evoked procoagulant response. The procoagulant property of red blood cells was not affected by the other three agents. The modulating effect of procoagulant activity was concomitant with and dependent on level of phosphatidylserine on the outer surface. Blockade of phosphatidylserine with lactadherin inhibited over 90% of tenase generation and prothrombinase activity and prolonged the coagulation time. CONCLUSIONS: We conclude that daunorubicin interacts with red blood cells in a manner that increases phosphatidylserine exposure and consequent procoagulant activity. Lactadherin is an efficient anticoagulant of this process.

Lactadherin and procoagulant activities of red blood cells in cyclosporine induced thrombosis.

BACKGROUND: The side effects of cyclosporine therapy include thromboembolic complications. However, the mechanisms underlying the hypercoagulable state induced by cyclosporine are not fully understood. Cyclosporine binds to red blood cells (RBCs) with a high affinity in circulation and alters the membranes of RBCs. Therefore, we propose that such alterations in RBCs membranes play a role in cyclosporine-induced coagulopathy and this disorder may be rectified by lactadherin, a phosphatidylserine binding protein. METHODS: RBCs from healthy adults were treated with various concentrations of cyclosporine. Procoagulant activity of the RBC membrane was measured by the single stage recalcification time and confirmed by detection of tenase and thrombin assembly through enzymatic assays. Inhibition assays of coagulation were carried out in the presence of lactadherin, annexin V or antitissue factor. Phosphatidylserine exposure was detected by flow cytometry and confocal microscopy through binding with fluorescein isothiocyanate (FITC)-labeled lactadherin as well as FITC annexin V. RESULTS: RBCs treated with cyclosporine demonstrated increased procoagulant activity. Cyclosporine treatment markedly shortened the clotting time of RBCs ((305 +/- 10) seconds vs (366 +/- 15) seconds) and increased the generation of intrinsic factor Xase ((7.68 +/- 0.99) nmol/L vs (2.86 +/- 0.11) nmol/L) and thrombin ((15.83 +/- 1.37) nmol/L vs (4.88 +/- 0.13) nmol/L). Flow cytometry and confocal microscopy indicated that cyclosporine treatment induced an increased expression of phosphatidylserine on the RBC membrane. Lactadherin was more sensitive in detecting phosphatidylserine exposure of the RBC membrane than annexin V. The modulating effect of procoagulant activity was concomitant with and dependent on phosphatidylserine exposure. Blocking of phosphatidylserine with lactadherin effectively inhibited over 90% of FXa generation and prothrombinase activity and prolonged coagulation time. CONCLUSIONS: Procoagulant properties of RBCs membranes resulting from phosphatidylserine exposure may play an important role in cyclosporine-induced thrombosis. Lactadherin can be used as a sensitive probe for phosphatidylserine detection. Its high affinity for phosphatidylserine may provide a new approach for the treatment of cyclosporine induced thrombogenic properties.

Nutritional risk, malnutrition (undernutrition), overweight, obesity and nutrition support among hospitalized patients in Beijing teaching hospitals.

The purpose of this study was to test the suitability of Nutritional Risk Screening 2002 (NRS 2002) among hospitalized patients and to determine the prevalence of nutritional risk, undernutrition, overweight, obesity, nutritional support and the changes of nutritional risk from admission to discharge or over a two-week period. A prospective descriptive design was used to describe patients' data collected at three Beijing teaching hospitals. A total number of 1500 consecutive patients, who met the inclusion criteria on admission and provided informed consent, were enrolled. The NRS 2002 was completed by 97.7% of all patients in this study. The overall prevalence of nutritional risk was 27.3%, the prevalence of undernutrition, overweight and obesity was 9.2%, 34.8%, and 10.2%, respectively at admission. Only 24.9% of patients who were at nutritional risk received nutritional support while 6% of non-risk patients received nutritional support. The overall prevalence of nutritional risk changed from 27.3% to 31.9% (p < 0.05), and the prevalence of undernutrition, overweight and obesity changed from 9.2% to 11.7% (p < 0.05), from 34.8% to 31.8% (p > 0.05) and from 10.2% to 8.6% (p > 0.05), respectively during hospitalization. Nutritional Risk Screening 2002 was a feasible nutritional risk screening tool in selected Beijing teaching hospitals. The prevalence of nutritional risk observed was nearly 30%. Inappropriate use of nutritional support was observed in hospitalized patients. The prevalence of nutritional risk increased in surgical patients during hospitalization.