HDAC inhibitor and proteasome inhibitor induce cleavage and exosome-mediated secretion of HSP90 in mouse pluripotent stem cells.

Heat shock protein 90 (HSP90), one of the molecular chaperones, stabilizes several proteins necessary to maintain pluripotency of embryonic stem (ES) cells. Recently, we reported that HDAC inhibitors and proteasome inhibitors down-regulate HSP90 activity through HSP90 cleavage induced by reactive oxygen species (ROS) generation and caspase 10 activation in various cancer cells. In this study, we investigated HSP90 cleavage in mouse ES cells. HDAC inhibitors and proteasome inhibitors induced HSP90 cleavage in the mouse ES cell line R1, and the cleaved HSP90 was barely found in the cells and instead secreted out of the cells through the exosome. The HSP90 cleavage was associated with ROS generation and caspase 10 activation. In addition, HDAC inhibitor and proteasome inhibitor induced Fas expression, and the inhibition of caspase 8, a downstream molecule of Fas, blocked HSP90 cleavage. Therefore, HDAC inhibitor- and proteasome inhibitor-mediated HSP90 cleavage was induced by ROS generation and Fas expression. We observed similar results in mouse induced pluripotent stem (iPS) cells. Taken together, HSP90 cleavage was induced in mouse pluripotent cells similarly to cancer cells but differently regulated through Fas expression and exosomal secretion. These findings will be helpful in elucidating the regulation of HSP90 upon stress in pluripotent stem cells.

Caspase-10 affects the pathogenesis of primary biliary cholangitis by regulating inflammatory cell death.

Primary biliary cholangitis (PBC) is an autoimmune disease that involves chronic inflammation and injury to biliary epithelial cells. To identify critical genetic factor(s) in PBC patients, we performed whole-exome sequencing of five female siblings, including one unaffected and four affected sisters, in a multi-PBC family, and identified 61 rare heterozygote variants that segregated only within the affected sisters. Among them, we were particularly interested in caspase-10, for although several caspases are involved in cell death, inflammation and autoimmunity, caspase-10 is little known from this perspective. We generated caspase-10 knockout macrophages, and then investigated the obtained phenotypes in comparison to those of its structurally similar protein, caspase-8. Unlike caspase-8, caspase-10 does not play a role during differentiation into macrophages, but after differentiation, it regulates the process of inflammatory cell deaths such as necroptosis and pyroptosis more strongly. Interestingly, caspase-10 displays better protease activity than caspase-8 in the process of RIPK1 cleavage, and an enhanced ability to form a complex with RIPK1 and FADD in human macrophages. Higher inflammatory cell death affected the fibrotic response of hepatic stellate cells; this effect could be recovered by treatment with UDCA and OCA, which are currently approved for PBC patients. Our findings strongly indicate that the defective roles of caspase-10 in macrophages contribute to the pathogenesis of PBC, thereby suggesting a new therapeutic strategy for PBC treatment.

Proteome-wide covalent ligand discovery in native biological systems.

Small molecules are powerful tools for investigating protein function and can serve as leads for new therapeutics. Most human proteins, however, lack small-molecule ligands, and entire protein classes are considered 'undruggable'. Fragment-based ligand discovery can identify small-molecule probes for proteins that have proven difficult to target using high-throughput screening of complex compound libraries. Although reversibly binding ligands are commonly pursued, covalent fragments provide an alternative route to small-molecule probes, including those that can access regions of proteins that are difficult to target through binding affinity alone. Here we report a quantitative analysis of cysteine-reactive small-molecule fragments screened against thousands of proteins in human proteomes and cells. Covalent ligands were identified for >700 cysteines found in both druggable proteins and proteins deficient in chemical probes, including transcription factors, adaptor/scaffolding proteins, and uncharacterized proteins. Among the atypical ligand-protein interactions discovered were compounds that react preferentially with pro- (inactive) caspases. We used these ligands to distinguish extrinsic apoptosis pathways in human cell lines versus primary human T cells, showing that the former is largely mediated by caspase-8 while the latter depends on both caspase-8 and -10. Fragment-based covalent ligand discovery provides a greatly expanded portrait of the ligandable proteome and furnishes compounds that can illuminate protein functions in native biological systems.

Neochamaejasmin B extracted from Stellera chamaejasme L. induces apoptosis through caspase-10-dependent way in insect neuronal cells.

To explore the toxicity mechanisms of neochamaejasmin B (NCB) extracted from Stellera chamaejasme L., we first evaluated its cytotoxicity in neuronal cells of Helicoverpa zea (AW1 cells). NCB inhibited cell growth and was cytotoxic to AW1 cells in a dose-dependent manner. Further, transmission electron microscopy (TEM) was used to analyze the microstructure, and typical apoptotic characteristics were observed in AW1 cells treated with NCB. Moreover, the NCB-induced apoptosis was dose dependent. Subsequently, we explored the mechanism of apoptosis. A decline in the mitochondrial membrane potential (MMP) was found. Also, the levels of Bax were increased with increases in drug concentration, but there was no statistical difference in Bcl-2 levels at different NCB doses. Caspase-3 and caspase-10 activity was increased. These findings confirmed that NCB induced apoptosis in AW1 cells through a caspase-10-dependent mechanism. The results provide the basic information needed for understanding the toxicity and mechanisms of action of NCB, which could potentially be used to develop NCB as a new insecticide.

Variants in CASP10, a diagnostic challenge: Single center experience and review of the literature.

Autoimmune lymphoproliferative syndrome is a primary immunodeficiency caused by variants in FAS-mediated apoptosis related genes and is characterized by lymphadenopathy, splenomegaly and autoimmunity. A total of six different variants in CASP10 have been described as potential causative of disease, although two of them have recently been considered polymorphisms. The high allele frequency of these variants in healthy population in addition to the broad clinical spectrum of the disease difficult the interpretation of their pathogenicity. Here, we describe the clinical and analytical findings of three new patients carrying variants in CASP10 and summarize 12 more cases from the literature. Autoimmune cytopenias, adenopathies and increment of TCRαß+CD4-CD8- cells have been the most common findings, being possibly the FAS-mediated apoptosis pathway the pathogenic mechanism of this disease. The clinical impact and the consequences of CASP10 variants are not fully elucidated, therefore the description of new cases will contribute to solve this issue.

Long noncoding RNA PVT1 facilitates high glucose-induced cardiomyocyte death through the miR-23a-3p/CASP10 axis.

Dilated cardiomyopathy (DCM) is the leading cause of morbidity and mortality in diabetic patients. Long noncoding RNA plasmacytoma variant translocation 1 (PVT1) has been shown to be related to the pathogenesis of DCM. However, the mechanism by which PVT1 regulates DCM pathogenesis is unclear. High glucose level was employed to construct a DCM cell model in vitro. Cell viability was determined via cell counting kit-8 assay. The level of lactate dehydrogenase (LDH) was measured with the corresponding kit. Expression levels of PVT1, miR-23a-3p, and caspase-10 (CASP10) messenger RNA were evaluated with a quantitative real-time polymerase chain reaction. Cell apoptosis was assessed by flow cytometry assay. Protein levels of B-cell lymphoma 2-associated X (Bax), cleaved-caspase-3 (cleaved-casp-3), and CASP10 were examined via western blot analysis. The relationship between PVT1 or CASP10 and miR-23a-3p was verified with dual-luciferase reporter assay. We observed that PVT1 and CASP10 were upregulated while miR-23a-3p was downregulated in high glucose-induced cardiomyocytes. High glucose levels repressed cardiomyocyte activity and induced cardiomyocyte apoptosis, but this influence was antagonized by PVT1 knockdown or miR-23a-3p overexpression. Furthermore, PVT1 acted as a sponge for miR-23a-3p, and miR-23a-3p inhibition counterbalanced the influence of PVT1 silencing on viability and apoptosis of cardiomyocytes under high glucose level treatment. PVT1 could increase CASP10 expression via sponging miR-23a-3p. In conclusion, PVT1 acted as a deleterious lncRNA in DCM. PVT1 facilitated cardiomyocyte death by regulating the miR-23a-3p/CASP10, which offered a new mechanism to comprehend the pathogenesis of DCM.

Stoichiometry of the CD95 death-inducing signaling complex: experimental and modeling evidence for a death effector domain chain model.

The CD95 (Fas/APO-1) death-inducing signaling complex (DISC) is essential for the initiation of CD95-mediated apoptotic and nonapoptotic responses. The CD95 DISC comprises CD95, FADD, procaspase-8, procaspase-10, and c-FLIP proteins. Procaspase-8 and procaspase-10 are activated at the DISC, leading to the formation of active caspases and apoptosis initiation. In this study we analyzed the stoichiometry of the CD95 DISC. Using quantitative western blots, mass spectrometry, and mathematical modeling, we reveal that the amount of DED proteins procaspase-8/procaspase-10 and c-FLIP at the DISC exceeds that of FADD by several-fold. Furthermore, our findings imply that procaspase-8, procaspase-10, and c-FLIP could form DED chains at the DISC, enabling the formation of dimers and efficient activation of caspase-8. Taken together, our findings provide an enhanced understanding of caspase-8 activation and initiation of apoptosis at the DISC.

FAS-mediated apoptosis impairment in patients with ALPS/ALPS-like phenotype carrying variants on CASP10 gene.

Autoimmune lymphoproliferative syndrome (ALPS) is a congenital disorder that results in an apoptosis impairment of lymphocytes, leading to chronic lymphoproliferation and autoimmunity, mainly autoimmune cytopenias. FAS gene defects are often responsible for the disease, the phenotype of which can vary from asymptomatic/mild forms to severe disease. More rarely, defects are associated to  other genes involved in apoptosis pathway, such as CASP10. Few data are available on CASP10-mutated patients. To date, two CASP10 mutations have been recognized as pathogenic (I406L and L258F) and others have been reported with controversial result on their pathogenicity (V410l, Y446C) or are known to be polymorphic variants (L522l). In this study, we evaluated apoptosis function in patients with an ALPS/ALPS-like phenotype carrying CASP10 variants. Molecular findings were obtained by next generation sequencing analysis of genes involved in immune dysregulation syndromes. Functional studies were performed after inducing apoptosis by FAS-ligand/TRIAL stimulation and analysing cell death and the function of CASP10, CASP8 and PARP proteins. We identified 6 patients with an ALPS (n = 2) or ALPS-like (n = 4) phenotype, carrying I406L (n = 1),V410l (n = 2),Y446C (n = 1) heterozygous CASP10 variants or the L522l polymorphisms (n = 2) associated with another polymorphic homozygote variant on CASP8 or a compound heterozygous mutation on TNFRSF13C. Apoptosis was impaired in all patients showing that such variants may play a role in the development of clinical phenotype.

SVMQA: support-vector-machine-based protein single-model quality assessment.

MOTIVATION: The accurate ranking of predicted structural models and selecting the best model from a given candidate pool remain as open problems in the field of structural bioinformatics. The quality assessment (QA) methods used to address these problems can be grouped into two categories: consensus methods and single-model methods. Consensus methods in general perform better and attain higher correlation between predicted and true quality measures. However, these methods frequently fail to generate proper quality scores for native-like structures which are distinct from the rest of the pool. Conversely, single-model methods do not suffer from this drawback and are better suited for real-life applications where many models from various sources may not be readily available. RESULTS: In this study, we developed a support-vector-machine-based single-model global quality assessment (SVMQA) method. For a given protein model, the SVMQA method predicts TM-score and GDT_TS score based on a feature vector containing statistical potential energy terms and consistency-based terms between the actual structural features (extracted from the three-dimensional coordinates) and predicted values (from primary sequence). We trained SVMQA using CASP8, CASP9 and CASP10 targets and determined the machine parameters by 10-fold cross-validation. We evaluated the performance of our SVMQA method on various benchmarking datasets. Results show that SVMQA outperformed the existing best single-model QA methods both in ranking provided protein models and in selecting the best model from the pool. According to the CASP12 assessment, SVMQA was the best method in selecting good-quality models from decoys in terms of GDTloss. AVAILABILITY AND IMPLEMENTATION: SVMQA method can be freely downloaded from http://lee.kias.re.kr/SVMQA/SVMQA_eval.tar.gz. CONTACT: jlee@kias.re.kr. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Improving low-accuracy protein structures using enhanced sampling techniques.

In this paper, we report results of using enhanced sampling and blind selection techniques for high-accuracy protein structural refinement. By combining a parallel continuous simulated tempering (PCST) method, previously developed by Zang et al. [J. Chem. Phys. 141, 044113 (2014)], and the structure based model (SBM) as restraints, we refined 23 targets (18 from the refinement category of the CASP10 and 5 from that of CASP12). We also designed a novel model selection method to blindly select high-quality models from very long simulation trajectories. The combined use of PCST-SBM with the blind selection method yielded final models that are better than initial models. For Top-1 group, 7 out of 23 targets had better models (greater global distance test total scores) than the critical assessment of structure prediction participants. For Top-5 group, 10 out of 23 were better. Our results justify the crucial position of enhanced sampling in protein structure prediction and refinement and demonstrate that a considerable improvement of low-accuracy structures is achievable with current force fields.

MicroRNA-421 inhibits caspase-10 expression and promotes breast cancer progression.

Breast cancer is one of the most prevalent and fatal diseases around the world. The mechanism of tumorigenesis in breast cancer remains to be clarified. miR-421 plays an oncogenic role in many cancers. Although, the clinical significance of miR-421 in patients with breast cancer is still to be investigated. Caspase-10 is one of the initiator of apoptosis. But the relationship between miR-421 and caspase-10 has not been investigated. In the present study, we found that miR-421 was expressed much higher in breast cancer tissues compared to those in adjacent non-tumor tissues. Furthermore, miR-421 promotes cell proliferation and colony formation in vitro. miR-421 inhibits cell apoptosis probably through restraining caspase-10 expression. Thus, miR-421 might be a potential diagnostic maker and therapeutic target for breast cancer.

Genetic variants in cell death pathway genes and HBV-related hepatocellular carcinoma among a Chinese Han population.

Cell death pathway plays an important role in apoptosis, and corruption of this signaling pathway has been shown to participate in carcinogenesis. We aimed at determining whether genetic variants in CASP8, CASP10 and CFLAR influence the development and clinical outcomes of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). A hospital-based case-control study, including 600 HCC cases and 600 HBsAg positive controls without HCC, was conducted to assess the relationship between 11 tagging SNPs in CASP8, CASP10 and CFLAR and HBV-related HCC risk and prognosis in a Chinese Han population. Among the 11 polymorphisms, only CASP8 rs3834129 (-652 6N ins/del) modified HCC risk. Compared with CASP8 -652 insins genotype, the deldel (adjusted OR 0.717, 95% CI 0.553-0.930) and insdel (adjusted OR 0.731, 95% CI 0.554-0.964) genotypes had a significantly decreased HCC risk. Furthermore, this polymorphism was significantly associated with decreased portal vein tumor thrombosis (adjusted OR 0.554; P = 0.044) and reduced postoperative recurrence (adjusted OR 0.356; P < 0.001) of resected HCC. In addition, the multivariate analysis showed that the -652 6N ins/del polymorphism was significantly associated with improved overall survival and recurrence-free survival of resected HCC patients. The expression levels of CASP8 in HCC tumor tissues were significantly lower than those in paracancerous liver tissues, although no significant association between -652 6N ins/del genotypes and the expression levels of CASP8 were observed in these tissues. These results suggest that the CASP8 -652 6N ins/del polymorphism may play a protective role in the development, progression, and survival of HBV-related HCC among the Chinese Han population.

MQAPsingle: A quasi single-model approach for estimation of the quality of individual protein structure models.

We present a Model Quality Assessment Program (MQAP), called MQAPsingle, for ranking and assessing the absolute global quality of single protein models. MQAPsingle is quasi single-model MQAP, a method that combines advantages of both "pure" single-model MQAPs and clustering MQAPs. This approach results in higher accuracy compared to the state-of-the-art single-model MQAPs. Notably, the prediction for a given model is the same regardless if this model is submitted to our server alone or together with other models. Proteins 2016; 84:1021-1028. © 2015 Wiley Periodicals, Inc.

Interferon α Induces the Apoptosis of Cervical Cancer HeLa Cells by Activating both the Intrinsic Mitochondrial Pathway and Endoplasmic Reticulum Stress-Induced Pathway.

The interferon α (IFN-α) has been often used as a sensitizing agent for the treatment of various malignancies such as hepatocellular carcinoma, malignant melanoma, and renal cell cancer by promoting the apoptosis of thesetumor cell types. However, the effect of IFN-α on cervical cancer remains unknown. In this study, HeLa cells were used as a testing model for the treatment of IFN-α on cervical cancer. The results indicate that IFN-α markedly inhibits the proliferation and induces the apoptosis of HeLa cells. The activation of caspase 3, the up-regulation of both Bim and cleaved poly (ADP-ribose) polymerase (PARP) 1, the down-regulation of Bcl-xL, as well as the release of cytochrome c from mitochondria were significantly induced upon IFN-α treatment, indicating that the intrinsic apoptotic pathway could be activated by IFN-α treatment. In addition, caspase 4-which is involved in the endoplasmic reticulum (ER) stress-induced apoptosis-was activated in response to IFN-α treatment. Knocking down caspase 4 by small interfering RNA (siRNA) markedly reduced the IFN-α-mediated cell apoptosis. However, no significant changes in the expressions of caspases 8 and 10 were observed upon IFN-α treatment, indicating that the apoptosis caused by IFN-α might be independent of the extrinsic apoptotic pathway. These findings suggest that IFN-α may possess anti-cervical cancer capacity by activating cell apoptosis via the intrinsic mitochondrial pathway and caspase-4-related ER stress-induced pathway.

Impaired Endothelial Regeneration Through Human Parvovirus B19-Infected Circulating Angiogenic Cells in Patients With Cardiomyopathy.

Human parvovirus B19 (B19V) is a common pathogen in microvascular disease and cardiomyopathy, owing to infection of endothelial cells. B19V replication, however, is almost restricted to erythroid progenitor cells (ErPCs). Endothelial regeneration attributable to bone marrow-derived circulating angiogenic cells (CACs) is a prerequisite for organ function. Because of many similarities of ErPCs and CACs, we hypothesized that B19V is a perpetrator of impaired endogenous endothelial regeneration. B19V DNA and messenger RNA from endomyocardial biopsy specimens, bone marrow specimens, and circulating progenitor cells were quantified by polymerase chain reaction analysis. The highest B19V DNA concentrations were found in CD34(+)KDR(+) cells from 17 patients with chronic B19V-associated cardiomyopathy. B19V replication intermediates could be detected in nearly half of the patients. Furthermore, chronic B19V infection was associated with impaired endothelial regenerative capacity. B19V infection of CACs in vitro resulted in expression of transcripts encoding B19V proteins. The capsid protein VP1 was identified as a novel inducer of apoptosis, as were nonstructural proteins. Inhibition studies identified so-called death receptor signaling with activation of caspase-8 and caspase-10 to be responsible for apoptosis induction. B19V causally impaired endothelial regeneration with spreading of B19V in CACs in an animal model in vivo. We thus conclude that B19V infection and damage to CACs result in dysfunctional endogenous vascular repair, supporting the emergence of primary bone marrow disease with secondary end-organ damage.

Deregulation of Fas ligand expression as a novel cause of autoimmune lymphoproliferative syndrome-like disease.

Autoimmune lymphoproliferative syndrome is frequently caused by mutations in genes involved in the Fas death receptor pathway, but for 20-30% of patients the genetic defect is unknown. We observed that treatment of healthy T cells with interleukin-12 induces upregulation of Fas ligand and Fas ligand-dependent apoptosis. Consistently, interleukin-12 could not induce apoptosis in Fas ligand-deficient T cells from patients with autoimmune lymphoproliferative syndrome. We hypothesized that defects in the interleukin-12 signaling pathway may cause a similar phenotype as that caused by mutations of the Fas ligand gene. To test this, we analyzed 20 patients with autoimmune lymphoproliferative syndrome of unknown cause by whole-exome sequencing. We identified a homozygous nonsense mutation (c.698G>A, p.R212*) in the interleukin-12/interleukin-23 receptor-component IL12RB1 in one of these patients. The mutation led to IL12RB1 protein truncation and loss of cell surface expression. Interleukin-12 and -23 signaling was completely abrogated as demonstrated by deficient STAT4 phosphorylation and interferon γ production. Interleukin-12-mediated expression of membrane-bound and soluble Fas ligand was lacking and basal expression was much lower than in healthy controls. The patient presented with the classical symptoms of autoimmune lymphoproliferative syndrome: chronic non-malignant, non-infectious lymphadenopathy, splenomegaly, hepatomegaly, elevated numbers of double-negative T cells, autoimmune cytopenias, and increased levels of vitamin B12 and interleukin-10. Sanger sequencing and whole-exome sequencing excluded the presence of germline or somatic mutations in genes known to be associated with the autoimmune lymphoproliferative syndrome. Our data suggest that deficient regulation of Fas ligand expression by regulators such as the interleukin-12 signaling pathway may be an alternative cause of autoimmune lymphoproliferative syndrome-like disease.

Differential response of head and neck cancer cell lines to TRAIL or Smac mimetics is associated with the cellular levels and activity of caspase-8 and caspase-10.

BACKGROUND: Current treatment strategies for head and neck cancer are associated with significant morbidity and up to 50% of patients relapse, highlighting the need for more specific and effective therapeutics. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) and Smac mimetics (SMs) are promising anticancer agents, but their effect on head and neck squamous cell carcinoma (HNSCC) remains unknown. METHODS: We examined the response of a panel of nine HNSCC cell lines to TRAIL and SMs and investigated the mechanism of cell type-specific response by functional analysis. RESULTS: Head and neck cancer cell lines revealed a converse response pattern with three cell lines being highly sensitive to Smac-164 (SM) but resistant to TRAIL, whereas the other six were sensitive to TRAIL but resistant to SM. Distinct protein expression and activation patterns were found to be associated with susceptibility of HNSCC cell lines to TRAIL and SM. Tumour necrosis factor-related apoptosis-inducing ligand sensitivity was associated with high caspase-8 and Bid protein levels, and TRAIL-sensitive cell lines were killed via the type II extrinsic apoptotic pathway. Smac mimetic-sensitive cells expressed low levels of caspase-8 and Bid but had high TNF-α expression. Smac mimetic-induced cell death was associated with caspase-10 activation, suggesting that in the absence of caspase-8, caspase-10 mediates response to SM. Cotreatment with TNF-α sensitised the resistant cells to SM, demonstrating a decisive role for TNF-α-driven feedback loop in SM sensitivity. CONCLUSIONS: Tumour necrosis factor-related apoptosis-inducing ligand and SMs effectively kill HNSCC cell lines and therefore represent potential targeted therapeutics for head and neck cancer. Distinct molecular mechanisms determine the sensitivity to each agent, with levels of TNF-α, caspase-8, Bid and caspase-10 providing important predictive biomarkers of response to these agents.

SSThread: Template-free protein structure prediction by threading pairs of contacting secondary structures followed by assembly of overlapping pairs.

Acquiring the three-dimensional structure of a protein from its amino acid sequence alone, despite a great deal of work and significant progress on the subject, is still an unsolved problem. SSThread, a new template-free algorithm is described here that consists of making several predictions of contacting pairs of α-helices and ß-strands derived from a database of experimental structures using a knowledge-based potential, secondary structure prediction, and contact map prediction followed by assembly of overlapping pair predictions to create an ensemble of core structure predictions whose loops are then predicted. In a set of seven CASP10 targets SSThread outperformed the two leading methods for two targets each. The targets were all ß-strand containing structures and most of them have a high relative contact order which demonstrates the advantages of SSThread. The primary bottlenecks based on sets of 74 and 21 test cases are the pair prediction and loop prediction stages.

Increasing maternal body mass index is associated with systemic inflammation in the mother and the activation of distinct placental inflammatory pathways.

Obese pregnant women have increased levels of proinflammatory cytokines in maternal circulation and placental tissues. However, the pathways contributing to placental inflammation in obesity are largely unknown. We tested the hypothesis that maternal body mass index (BMI) was associated with elevated proinflammatory cytokines in maternal and fetal circulations and increased activation of placental inflammatory pathways. A total of 60 women of varying pre-/early pregnancy BMI, undergoing delivery by Cesarean section at term, were studied. Maternal and fetal (cord) plasma were collected for analysis of insulin, leptin, IL-1beta, IL-6, IL-8, monocyte chemoattractant protein (MCP) 1, and TNFalpha by multiplex ELISA. Activation of the inflammatory pathways in the placenta was investigated by measuring the phosphorylated and total protein expression of p38-mitogen-activated protein kinase (MAPK), c-Jun-N-terminal kinase (JNK)-MAPK, signal transducer-activated transcription factor (STAT) 3, caspase-1, IL-1beta, IkappaB-alpha protein, and p65 DNA-binding activity. To determine the link between activated placental inflammatory pathways and elevated maternal cytokines, cultured primary human trophoblast (PHT) cells were treated with physiological concentrations of insulin, MCP-1, and TNFalpha, and inflammatory signaling analyzed by Western blot. Maternal BMI was positively correlated with maternal insulin, leptin, MCP-1, and TNFalpha, whereas only fetal leptin was increased with BMI. Placental phosphorylation of p38-MAPK and STAT3, and the expression of IL-1beta protein, were increased with maternal BMI; phosphorylation of p38-MAPK was also correlated with birth weight. In contrast, placental NFkappaB, JNK and caspase-1 signaling, and fetal cytokine levels were unaffected by maternal BMI. In PHT cells, p38-MAPK was activated by MCP-1 and TNFalpha, whereas STAT3 phosphorylation was increased following TNFalpha treatment. Maternal BMI is associated with elevated maternal cytokines and activation of placental p38-MAPK and STAT3 inflammatory pathways, without changes in fetal systemic inflammatory profile. Activation of p38-MAPK by MCP-1 and TNFalpha, and STAT3 by TNFalpha, suggests a link between elevated proinflammatory cytokines in maternal plasma and activation of placental inflammatory pathways. We suggest that inflammatory processes associated with elevated maternal BMI may influence fetal growth by altering placental function.

Investigation of the caspase-dependent mitochondrial apoptotic pathway in mononuclear cells of patients with systemic Lupus erythematosus.

BACKGROUND: This study aimed to explore the role of apoptosis initiators, caspase-9, caspase-10, mitochondrial anti-viral signaling protein (MAVS), and interferon regulatory factor 7 (pIRF7), in patients with systemic lupus erythematosus (SLE). METHODS: Leukocyte apoptosis was determined by flow cytometry, including annexin V, APO2.7, and 7-amino-actinomycin D (7-AAD) on each subtype of leukocyte in 35 patients with SLE, 15 disease controls, and 17 volunteer normal controls. Levels of caspase-9, caspase-10, MAVS, and pIRF7 in mononuclear cells and the disease activity index (SLEDAI) in the SLE patients were determined. Correlation among intracellular adaptor proteins and caspase levels were calculated. RESULTS: The SLE patients had higher APO2.7 in total leukocyte, lymphocyte, and monocytes, and higher late apoptosis markers in total leukocytes and neutrophils than normal controls (all p < 0.05). Disease activity was positively associated with the APO2.7 of CD19+ cells in SLE, but negatively associated with MAVS and caspase-9 levels (all p < 0.05). Markers of viral infection and anti-virus transcription factors like MDA5, MAVS, and pIRF7 were significantly higher in SLE patients than in disease controls (p < 0.05). Caspase-9 and caspase-10 levels positively correlated with MAVS and pIRF7 in SLE patients (p < 0.05). CONCLUSIONS: The disease activity of SLE is positively associated with APO2.7 level of CD19+ cells but negatively associated with MAVS and caspase-9 levels, which all point to a mitochondrial pathway.