Pristanic Acid Provokes Lipid,Protein, and DNA Oxidative Damage and Reduces the Antioxidant Defenses in Cerebellum of Young Rats

Zellweger syndrome (ZS) and some peroxisomal diseases are severe inherited disorders mainly characterized by neurological symptoms and cerebellum abnormalities, whose pathogenesis is poorly understood. Biochemically, these diseases are mainly characterized by accumulation of pristanic acid (Prist) and other fatty acids in the brain and other tissues. In this work, we evaluated the in vitro influence of Prist on redox homeostasis by measuring lipid, protein, and DNA damage, as well as the antioxidant defenses and the activities of aconitase and α-ketoglutarate dehydrogenase in cerebellum of 30-day-old rats. The effect of Prist on DNA damage was also evaluated in blood of these animals. Some parameters were also evaluated in cerebellum from neonatal rats and in cerebellum neuronal cultures. Prist significantly increased malondialdehyde (MDA) levels and carbonyl formation and reduced sulfhydryl content and glutathione (GSH) concentrations in cerebellum of young rats. It also caused DNA strand damage in cerebellum and induced a high micronuclei frequency in blood. On the other hand, this fatty acid significantly reduced α-ketoglutarate dehydrogenase and aconitase activities in rat cerebellum. We also verified that Prist-induced increase of MDA levels was totally prevented by melatonin and attenuated by α-tocopherol but not by the nitric oxide synthase inhibitor N^ω-nitro-l-arginine methyl ester, indicating the involvement of reactive oxygen species in this effect. Cerebellum from neonate rats also showed marked alterations of redox homeostasis, including an increase of MDA levels and a decrease of sulfhydryl content and GSH concentrations elicited by Prist. Finally, Prist provoked an increase of dichlorofluorescein (DCFH) oxidation in cerebellum-cultivated neurons. Our present data indicate that Prist compromises redox homeostasis in rat cerebellum and blood and inhibits critical enzymes of the citric acid cycle that are susceptible to free radical attack. The present findings may contribute to clarify the pathogenesis of the cerebellar alterations observed in patients affected by ZS and some peroxisomal disorders in which Prist is accumulated.     

Long-term follow-up of children with risk organ-negative Langerhans cell histiocytosis after 2-chlorodeoxyadenosine treatment

The nucleoside analogue, 2-chlorodeoxyadenosine (2CDA), was reported to be an active treatment for childhood Langerhans cell histiocytosis (LCH) without risk organ (RO−) involvement. However, we lack data on long-term effects of 2CDA treatment, including the disease reactivation rate, permanent sequelae and long-term tolerance. This study included 44 children from the French LCH registry, treated for a RO− LCH with 2CDA monotherapy (median number of six courses). The median age at the beginning of 2CDA was 3·6 years (range, 0·3–19·7 years) and the median follow-up after was 5·4 years (range, 0·6–15·1 years). Objective response to 2CDA was observed in 25 patients (56·8%), while six patients (13·6%) had stable disease and 13 patients (29·5%) exhibited progressive disease. Among patients without progression, only two experienced disease reactivation after 2CDA discontinuation. The five-year cumulative incidence of disease progression or reactivation after 2CDA therapy initiation was 34·3%. The lymphopenia reported in all cases [72% below absolute lymphocyte count (ALC) of 0·5 G/l], was addressed with appropriate prophylactic measures. Other toxicities above grade 2 were uncommon, and no second malignant neoplasm or neuropathy was reported. The five-year overall survival was 97·7%. In conclusion, we could confirm that 2CDA monotherapy was a beneficial long-term therapy for treating patients with RO− LCH. Appropriate management of induced immune deficiency is mandatory.     

Cell sheets of human dental pulp stem cells for future application in bone replacement

Objectives

To analyze the potential of human dental pulp stem cells (hDPSCs) for maintaining their undifferentiated status and osteogenic differentiation capacity when arranged in cell sheets (CSs) for future application in bone replacement.

Materials and methods

CSs were formed after being induced for 10–15 days by clonogenic medium containing additional vitamin C (20 μg/ml). The cell viability of hDPSC4s in the CSs was followed until 96 h using the Live/Dead® assay. The cells of the CSs were enzymatically dissociated and then compared with the original hDPSC4s. The two cell types were characterized immunophenotypically by flow cytometry using specific mesenchymal stem cell-associated markers (CD105, CD146, CD44, STRO-1, and OCT3/4) and non-associated markers (CD34, CD45, and CD14). Osteogenic differentiation was analyzed with the Alizarin red assay.

Results

Living cells were observed until 96 h in the CSs. Both cell types exhibited osteogenic differentiation and expressed the specific undifferentiated MSC-associated markers. Cells spontaneously detached from the CSs attached and proliferated at the bottom of the culture dishes.

Conclusions

Cells in the hDPSC4s cell sheets survived for at least 96 h. Moreover, the cells in the cell sheets retained their stemness and their osteogenic differentiation potential.

Clinical relevance

Cell sheets of hDPSCs could be employed as natural tri-dimensional structures for treating bone loss. This technique would be useful particularly for critical bone defects or any type of bone defects in patients carrying diseases that impair bone regeneration, such as diabetes mellitus, medication-related osteonecrosis of the jaw (MRONJ), and osteoporosis.

     

Murine CD27(?) Vγ6(+) γδ T cells producing IL-17A promote ovarian cancer growth via mobilization of protumor small peritoneal macrophages

Cancer-associated inflammation mobilizes a variety of leukocyte populations that can inhibit or enhance tumor cell growth in situ. These subsets include γδ T cells, which can infiltrate tumors and typically provide large amounts of antitumor cytokines, such as IFN-γ. By contrast, we report here that in a well-established transplantable (ID8 cell line) model of peritoneal/ovarian cancer, γδ T cells promote tumor cell growth. γδ T cells accumulated in the peritoneal cavity in response to tumor challenge and could be visualized within solid tumor foci. Functional characterization of tumor-associated γδ T cells revealed preferential production of interleukin-17A (IL-17), rather than IFN-γ. Consistent with this finding, both T cell receptor (TCR)δ-deficient and IL-17–deficient mice displayed reduced ID8 tumor growth compared with wild-type animals. IL-17 production by γδ T cells in the tumor environment was essentially restricted to a highly proliferative CD27⁽⁻⁾ subset that expressed Vγ6 instead of the more common Vγ1 and Vγ4 TCR chains. The preferential expansion of IL-17–secreting CD27⁽⁻⁾ Vγ6⁽⁺⁾ γδ T cells associated with the selective mobilization of unconventional small peritoneal macrophages (SPMs) that, in comparison with large peritoneal macrophages, were enriched for IL-17 receptor A, and for protumor and proangiogenic molecular mediators, which were up-regulated by IL-17. Importantly, SPMs were uniquely and directly capable of promoting ovarian cancer cell proliferation. Collectively, this work identifies an IL-17–dependent lymphoid/myeloid cross-talk involving γδ T cells and SPMs that promotes tumor cell growth and thus counteracts cancer immunosurveillance.Developing tumors are infiltrated by a variety of leukocyte subsets that can either promote or inhibit inflammation, and thus impact on cancer progression (1). Among such populations are γδ T cells, which are major players in lymphoid stress surveillance likely due to their recognition of stress-inducible molecules independently of MHC-mediated antigen presentation (2). Moreover, abundant IFN-γ secretion and cytotoxic effector functions endow γδ T cells with potent antitumor activity. This has been clearly documented in murine models of spontaneous (3), chemically induced (4), transgenic (5), and transplantable (6, 7) tumors. For example, in the widely used B16 melanoma model, γδ T cells were shown to infiltrate tumors very early and provided a critical source of IFN-γ that significantly delayed tumor growth (6, 7).Human γδ T cells also possess IFN-γ–secreting potential, which is displayed immediately at birth (8) and display cytotoxicity against tumor lines of diverse origin, including epithelial (9, 10) and hematological (11, 12) tumors. This has prompted the development of cancer clinical trials targeting γδ T cells, which have produced encouraging, albeit highly variable, degrees of therapeutic responses (13–15). There is therefore great interest in maximizing the antitumor functions of γδ T cells for cancer immunotherapy.Despite these highly promising reports, a clinical study on breast cancer tissue revealed a surprising inverse correlation between infiltrating γδ T cells and overall patient survival (16). In fact, γδ T cells represented the most significant independent prognostic factor for assessing severity of breast cancer (16). Similarly, a recent report on colorectal cancer showed a positive correlation between clinopathological parameters and the infiltration of γδ T cells specifically producing interleukin-17 (IL-17) (17). A tumor-promoting function of γδ T cells was also suggested in murine fibrosarcoma (18) and hepatocellular carcinoma (19) models, in which γδ T cells were the major cellular source of IL-17, which was required for optimal tumor growth in vivo. These data raise the interesting question as to whether distinct functional attributes of γδ T cells, for example differential cytokine production, may associate with markedly different outcomes for tumor growth.Along these lines, we have pioneered the identification of two distinct functional subsets of murine γδ T cells based on the expression levels of the CD27 coreceptor (20). We showed that robust IFN-γ production is associated with the CD27⁽⁺⁾ phenotype, whereas secretion of IL-17 is restricted to CD27⁽⁻⁾ γδ T cells. This dichotomy of hard-wired commitment to specific cytokine production is established during thymic development and maintained during the immune response to various infection agents (21, 22). Thus, the overall impact of γδ T cells in a given disease may depend on the balance between distinct proinflammatory effector cell subsets.Building on these foundations, we have here analyzed the overall and subset-specific contributions of γδ T cells to a well-established murine syngeneic model of ovarian cancer (ID8; transplantable cell line) that has a strong inflammatory component (23–25), akin to that observed in human patients with high-grade serous ovarian cancer (25, 26). In this murine model, we demonstrate that γδ T cells are major sources of IL-17, and both T cell receptor (TCR)δ-deficient and IL-17–deficient mice display reduced ID8 tumor growth. Interestingly, IL-17 production by γδ T cells in the tumor environment is essentially restricted to a CD27⁽⁻⁾ subset that does not express the commonly used Vγ1 or Vγ4 TCR chains, but rather Vγ6; these Vγ6⁽⁺⁾ cells are highly biased toward IL-17 production, in contrast to their IFN-γ–producing Vγ1⁽⁺⁾ and Vγ4⁽⁺⁾ counterparts. The ID8 tumor environment gets progressively enriched in the IL-17–promoting factor IL-7, whose receptor is highly expressed on Vγ6⁽⁺⁾ cells. This associates with preferential Vγ6⁽⁺⁾ cell proliferation and accumulation of IL-17 in the tumor bed, which in turn induces the mobilization of (recently described) small peritoneal macrophages (SPMs) that are enriched in IL-17 receptor A (IL-17RA) and in protumor and proangiogenic molecular mediators. Importantly, in comparison with large peritoneal macrophages (LPMs), SPMs can strongly and directly promote ovarian cancer cell proliferation. In summary, our work identifies an IL-17–dependent γδ T-cell/SPM axis that promotes tumor cell growth and thus opposes the widely accepted antitumor (and IFN-γ mediated) function of γδ T cells.     

ADHD and the externalizing spectrum: direct comparison of categorical,continuous, and hybrid models of liability in a nationally representative sample

Purpose

Alcohol use disorders, substance use disorders, and antisocial personality disorder share a common externalizing liability, which may also include attention-deficit hyperactivity disorder (ADHD). However, few studies have compared formal quantitative models of externalizing liability, with the aim of delineating the categorical and/or continuous nature of this liability in the community. This study compares categorical, continuous, and hybrid models of externalizing liability.

Method

Data were derived from the 2004–2005 National Epidemiologic Survey on Alcohol and Related Conditions (N = 34,653). Seven disorders were modeled: childhood ADHD and lifetime diagnoses of antisocial personality disorder (ASPD), nicotine dependence, alcohol dependence, marijuana dependence, cocaine dependence, and other substance dependence.

Results

The continuous latent trait model provided the best fit to the data. Measurement invariance analyses supported the fit of the model across genders, with females displaying a significantly lower probability of experiencing externalizing disorders. Cocaine dependence, marijuana dependence, other substance dependence, alcohol dependence, ASPD, nicotine dependence, and ADHD provided the greatest information, respectively, about the underlying externalizing continuum.

Conclusions

Liability to externalizing disorders is continuous and dimensional in severity. The findings have important implications for the organizational structure of externalizing psychopathology in psychiatric nomenclatures.     

Perceiving nonverbal behavior: Neural correlates of processing movement fluency and contingency in dyadic interactions

Despite the fact that nonverbal dyadic social interactions are abundant in the environment, the neural mechanisms underlying their processing are not yet fully understood. Research in the field of social neuroscience has suggested that two neural networks appear to be involved in social understanding: (1) the action observation network (AON) and (2) the social neural network (SNN). The aim of this study was to determine the differential contributions of the AON and the SNN to the processing of nonverbal behavior as observed in dyadic social interactions. To this end, we used short computer animation sequences displaying dyadic social interactions between two virtual characters and systematically manipulated two key features of movement activity, which are known to influence the perception of meaning in nonverbal stimuli: (1) movement fluency and (2) contingency of movement patterns. A group of 21 male participants rated the “naturalness” of the observed scenes on a four‐point scale while undergoing fMRI. Behavioral results showed that both fluency and contingency significantly influenced the “naturalness” experience of the presented animations. Neurally, the AON was preferentially engaged when processing contingent movement patterns, but did not discriminate between different degrees of movement fluency. In contrast, regions of the SNN were engaged more strongly when observing dyads with disturbed movement fluency. In conclusion, while the AON is involved in the general processing of contingent social actions, irrespective of their kinematic properties, the SNN is preferentially recruited when atypical kinematic properties prompt inferences about the agents' intentions. Hum Brain Mapp 35:1362–1378, 2014. © 2013 Wiley Periodicals, Inc.     

Clustering of body composition,blood pressure and physical activity in Portuguese families

Aim: The purposes of this study were: (i) to identify familial resemblances in body fat, blood pressure (BP) and total physical activity (TPA); (ii) to estimate the magnitude of their genetic and environmental influences; and (iii) to investigate shared familial aggregation among these phenotypes.

Subjects and methods: The sample comprised 260 nuclear families from Portugal. Body fat was assessed by bioelectrical impedance. BP was measured by an oscillometric device. TPA was estimated by the Baecke questionnaire. Familial correlation analyses were performed using Generalized Estimating Equations. Quantitative genetic modelling was used to estimate maximal heritability, genetic and environmental correlations.

Results: Familial intra-trait correlations ranged from 0.15–0.38. Genetic and common environmental factors explained from 30%--44% of fat mass depots and BP and 24% of TPA. Genetic correlations were significant between BP and the fat mass traits (p?p?Conclusions: The results suggest familial resemblance in the variation of body fat, BP and TPA, showing partial pleiotropic effects in the variation in body fat phenotypes and BP. TPA only shares common environmental influences with BP and body fat traits.     

Relatively favorable outcome after allogeneic stem cell transplantation for BCR‐ABL1‐positive AML: A survey from the acute leukemia working party of the European Society for blood and marrow transplantation (EBMT)

The aim of the study was to assess the role of allogeneic stem cell transplantation (SCT) in patients diagnosed with BCR‐ABL1‐positive acute myeloid leukemia (AML). Fifty‐seven patients (median age, 48 years, range: 19‐67) with BCR‐ABL1 positive AML undergoing SCT were identified. The majority of the patients (70%) received a TKI before the transplant. At SCT 48 patients were in CR (45 in CR1), while 9 patients were transplanted in a more advanced stage of the disease. MRD was negative (BCR‐ABL1/ABL < 10⁴) at time of SCT in 36.1% (14/40). After SCT, 16 (61.5%) out of 26 patients with MRD positive at transplantation reached MRD negativity. After a median follow‐up of 6.3 years (0.7–14.2), NRM, RI, LFS, OS, and GRFS at 5 years were 18.1%, 37%, 44.2%, 53.8%, and 32.1%, respectively. The cumulative incidence of acute GvHD grade II‐IV was 16.4%, incidence of chronic GvHD 24.9%, and of extensive cGvHD 21.4%, respectively. In patients who received SCT in CR1, 5‐yr NRM, RI, LFS, OS, and GRFS were 15.9%, 36.4%, 46.5%, 59.4%, and 34.9%, respectively. Univariate analysis showed that age (<50 vs. ≥50 years) was associated with RI (5‐yr: 22.7 vs. 50%), LFS (5‐yr: 61.9 vs. 31.8%), and GRFS (5‐yr: 52.4 vs. 18.2%), whereas MRD‐negative status before SCT was associated with an improved GRFS (38.9 vs. 16.7%). We conclude that the outcome of patients <50 years of age with BCR‐ABL1‐positive AML receiving allogeneic SCT in CR is relatively favorable, possibly reflecting the beneficial effect of the use of TKI.