Dysregulation in microRNA Expression Is Associated with Alterations in Immune Functions in Combat Veterans with Post-Traumatic Stress Disorder

While the immunological dysfunction in combat Veterans with post-traumatic stress disorder (PTSD) has been well documented, the precise mechanisms remain unclear. The current study evaluated the role of microRNA (miR) in immunological dysfunction associated with PTSD. The presence of peripheral blood mononuclear cells (PBMC) and various lymphocyte subsets in blood collected from PTSD patients were analyzed. Our studies demonstrated that the numbers of both PBMC and various lymphocyte subsets increased significantly in PTSD patients. When T cells were further analyzed, the percentage of Th1 cells and Th17 cells increased, regulatory T cells(Tregs) decreased, while Th2 cells remained unaltered in PTSD patients. These data correlated with increased plasma levels of IFN-γ and IL-17 while IL-4 showed no significant change. The increase in PBMC counts, Th1 and Th17 cells seen in PTSD patients correlated with the clinical scores. High-throughput analysis of PBMCs for 1163 miRs showed that the expression of a significant number of miRs was altered in PTSD patients. Pathway analysis of dysregulated miRs seen in PTSD patients revealed relationship between selected miRNAs and genes that showed direct/indirect role in immunological signaling pathways consistent with the immunological changes seen in these patients. Of interest was the down-regulation of miR-125a in PTSD, which specifically targeted IFN-γ production. Together, the current study demonstrates for the first time that PTSD was associated with significant alterations in miRNAs, which may promote pro-inflammatory cytokine profile. Such epigenetic events may provide useful tools to identify potential biomarkers for diagnosis, and facilitate therapy of PTSD.     

Molecular Alterations Associated with Breast Cancer Mortality

Background

Breast cancer is a heterogeneous disease and patients with similar pathologies and treatments may have different clinical outcomes. Identification of molecular alterations associated with disease outcome may improve risk assessment and treatments for aggressive breast cancer.

Methods

Allelic imbalance (AI) data was generated for 122 invasive breast tumors with known clinical outcome. Levels and patterns of AI were compared between patients who died of disease (DOD) and those with ≥5 years disease-free survival (DFS) using Student t-test and chi-square analysis with a significance value of P<0.05.

Results

Levels of AI were significantly higher in tumors from the 31 DOD patients (28.6%) compared to the 91 DFS patients (20.1%). AI at chromosomes 7q31, 8p22, 13q14, 17p13.3, 17p13.1 and 22q12.3 was associated with DOD while AI at 16q22–q24 was associated with DFS. After multivariate analysis, AI at chromosome 8p22 remained an independent predictor of breast cancer mortality. The frequency of AI at chromosome 13q14 was significantly higher in patients who died ≥5 years compared to those who died <5 years from diagnosis.

Conclusion

Tumors from DOD compared to DFS patients are marked by increased genomic instability and AI at chromosome 8p22 is significantly associated with breast cancer morality, independent of other clinicopathological factors. AI at chromosome 13q14 was associated with late (>5-years post-diagnosis) mortality but not with death from disease within five years, suggesting that patients with short- and long-term mortality may have distinct genetic diseases.     

Evidence for Proteomic and Metabolic Adaptations Associated with Alterations of Seed Yield and Quality in Sulfur-limited Brassica napus L

In Brassica napus, seed yield and quality are related to sulfate availability, but the seed metabolic changes in response to sulfate limitation remain largely unknown. To address this question, proteomics and biochemical studies were carried out on mature seeds obtained from plants grown under low sulfate applied at the bolting (LS32), early flowering (LS53), or start of pod filling (LS70) stage. The protein quality of all low-sulfate seeds was reduced and associated with a reduction of S-rich seed storage protein accumulation (as Cruciferin Cru4) and an increase of S-poor seed storage protein (as Cruciferin BnC1). This compensation allowed the protein content to be maintained in LS70 and LS53 seeds but was not sufficient to maintain the protein content in LS32 seeds. The lipid content and quality of LS53 and LS32 seeds were also affected, and these effects were primarily associated with a reduction of C18-derivative accumulation. Proteomics changes related to lipid storage, carbohydrate metabolism, and energy (reduction of caleosins, phosphoglycerate kinase, malate synthase, ATP-synthase β-subunit, and thiazole biosynthetic enzyme THI1 and accumulation of β-glucosidase and citrate synthase) provide insights into processes that may contribute to decreased oil content and altered lipid composition (in favor of long-chain fatty acids in LS53 and LS32 seeds). These data indicate that metabolic changes associated with S limitation responses affect seed storage protein composition and lipid quality. Proteins involved in plant stress response, such as dehydroascorbate reductase and Cu/Zn-superoxide dismutase, were also accumulated in LS53 and LS32 seeds, and this might be a consequence of reduced glutathione content under low S availability. LS32 treatment also resulted in (i) reduced germination vigor, as evidenced by lower germination indexes, (ii) reduced seed germination capacity, related to a lower seed viability, and (iii) a strong decrease of glyoxysomal malate synthase, which is essential for the use of fatty acids during seedling establishment.As the third main oil crop worldwide (58.5 Mt in 2011), oilseed rape represents a major renewable resource for food (oil, meal) and nonfood uses (green energy, green chemistry). Relative to other crops such as cereals, oilseed rape (Brassica napus L.) requires high amounts of sulfur (S) to sustain its growth and yield (1–3). The reduction of S atmospheric deposits observed over recent decades has forced farmers to add S fertilizer in order to maintain seed yield and quality. A previous study highlighted the necessity of satisfying plant S requirements until the start of pod filling to ensure yield as well as high lipid and protein contents (4). These observations emphasize the importance of a detailed understanding of the impact of S limitation on seed oil and protein quality and of the processes involved.During Brassica napus seed development, the carbon (C) provided by source organs as sucrose is assimilated through both oxidative phosphate and glycolytic pathways. These pathways provide precursors for fatty acid synthesis in the form of acetyl-CoA, an S-containing metabolite. Glycolysis enables the production of phosphoenolpyruvate (PEP)¹ from hexose phosphates formed from sucrose cleavage and is considered as the predominant metabolic pathway for the production of these precursors. During seed development, PEP is principally transported to the plastid, where it is dephosphorylated by pyruvate kinase into pyruvate, which is the substrate responsible for acetyl-CoA formation, used for fatty acid synthesis inside plastids by acetyl-CoA carboxylase and fatty acid synthase (5, 6). In plastids of Brassica napus cells, acetyl-CoA carboxylase, which catalyzes the carboxylation of acetyl-CoA to form malonyl-CoA, needed to sustain de novo fatty acid synthesis (C16:0, C18:0, C18:1), is present both in the prokaryotic form, consisting of a protein complex of four assembled subunits, and in the eukaryotic form, as a single large multifunctional polypeptide (7). In the cytosol, PEP can also produce pyruvate from cytosolic pyruvate kinase or through a system involving PEP carboxylase, malate dehydrogenase (MDH), and chloroplastidial malic enzyme. The PEP carboxylase–MDH–malic enzyme pathway might be important, as PEP carboxylase activity is substantial during Brassica napus seed development, relative to most nonphotosynthetic tissues (8). The cytosolic pyruvate can also be transported to the mitochondria to produce energy through the TCA cycle. Nevertheless, in maturing B. napus embryos, flux through the complete TCA cycle is absent and oxidation of mitochondrial substrate only weakly contributes to ATP production (9). The mitochondrial metabolism is mostly devoted to cytosolic fatty acid elongation, because the citrate formed in the TCA cycle is exported into the cytosol and used for the production of acetyl-CoA by ATP citrate lyase (10). The multifunctional acetyl-CoA carboxylase, also present in the cytosol, provides malonyl-CoA required for fatty acid elongation (C20:0, C20:1, C22:0) and for a variety of reactions including the synthesis of secondary metabolites such as flavonoids and anthocyanins and the malonylation of some amino acids and secondary metabolites (7).After the extraction of oil from B. napus seeds, the residual protein-rich meal is used for animal feed. Cruciferins are the major form of seed storage protein (SSP) found in Brassica species. These 11–12S globulins are synthesized inside the endoplasmic reticulum during seed development as a precursor form of 50 to 60 kDa, prior to being transported via the Golgi to vacuoles, where they are partially cleaved during a later stage by vacuolar proteases, leading to the formation of acidic α- and basic β-subunits. In dry mature seeds, cruciferins stored in vacuoles are composed of six pairs of acidic and basic associated subunits that interact noncovalently. These subunits are subjected to limited proteolysis at the C-terminal end (11–13), which is repressed by S limitation treatments in Arabidopsis thaliana (14). During germination, SSPs are broken down and used as a source of nitrogen (N), C, and S by the germinating seedling (11). The effects of S limitation on seed protein quality have been studied in Arabidopsis thaliana (14), in which S limitation leads to decreased seed protein content, principally associated with a decrease in S-rich SSP accumulation (At12S3, At2S3). In oilseed rape, the N/S ratio in seed protein increases in S-limited conditions (2). Many attempts have been made to increase the seed methionine content of Brassicaceae species (see Ref. 15 for a review). Transgenic Brassica napus lines carrying a gene encoding the Brazil nut (Bertholletia excelsa) 2S albumin, a methionine-rich storage protein (representing 18.8% of the total amino acids of this protein), and fused with the regulatory region of the phaseolin gene show significant enhancement of total seed methionine accumulation under non-S-limiting conditions (16), improving the nutritional value of Brassica napus seeds. Unfortunately, this Brazil nut 2S sulfur-rich albumin was found to be allergenic (17). Recently, it has been reported that reduced activity in homocysteine methyltransferase 2, a methionine biosynthetic enzyme specifically expressed in vegetative tissues, leads to an increased accumulation of methionine in Arabidopsis thaliana seeds (18). To our knowledge, such an attempt has not yet been made in the context of S deficiency. Moreover, although the effect of S deficiency on the major seed proteins has been investigated in Arabidopsis (14), there has been no report on the effect of S limitation on the seed proteome in Brassica napus L., a major oil crop grown worldwide.With the knowledge that S limitation leads to perturbations of S, C, and N metabolism (19–22), and considering the importance of such metabolism for lipid and protein synthesis in developing seeds, this study aimed to characterize the effects of S limitation applied at different growth stages on Brassica napus seed quality. In addition, the study reveals the adaptations that may occur during seed maturation in response to S limitation. Their consequences for the maintenance of seed yield, lipid and protein quality, and germination capacity are also discussed.     

No Evidence for Prolonged Visible Persistence in Patients with Schizophrenia

Background

Temporal visual processing is strongly deteriorated in patients with schizophrenia. For example, the interval required between a visual stimulus and a subsequent mask has to be much longer in schizophrenic patients than in healthy controls. We investigated whether this deficit in temporal resolution is accompanied by prolonged visual persistence and/or deficient temporal precision (temporal asynchrony perception).

Methodology/Principal Findings

We investigated visual persistence in three experiments. In the first, measuring temporal processing by so-called backward masking, prolonged visible persistence is supposed to decrease performance. In the second experiment, requiring temporal integration, prolonged persistence is supposed to improve performance. In the third experiment, we investigated asynchrony detection, as another measure of temporal resolution. Eighteen patients with schizophrenia and 15 healthy controls participated. Asynchrony detection was intact in the patients. However, patients'' performance was inferior compared to healthy controls in the first two experiments. Hence, temporal processing in schizophrenic patients is indeed significantly impaired but this impairment is not caused by prolonged temporal integration.

Conclusions/Significance

Our results argue against a generally prolonged visual persistence in patients with schizophrenia. Together with the preserved ability of patients, to detect temporal asynchronies in permanently presented stimuli, the results indicate a more specific deficit in temporal processing of schizophrenic patients.     

Altered Gene Expression Associated with microRNA Binding Site Polymorphisms

Allele-specific gene expression associated with genetic variation in regulatory regions can play an important role in the development of complex traits. We hypothesized that polymorphisms in microRNA (miRNA) response elements (MRE-SNPs) that either disrupt a miRNA binding site or create a new miRNA binding site can affect the allele-specific expression of target genes. By integrating public expression quantitative trait locus (eQTL) data, miRNA binding site predictions, small RNA sequencing, and Argonaute crosslinking immunoprecipitation (AGO-CLIP) datasets, we identified genetic variants that can affect gene expression by modulating miRNA binding efficiency. We also identified MRE-SNPs located in regions associated with complex traits, indicating possible causative mechanisms associated with these loci. The results of this study expand the current understanding of gene expression regulation and help to interpret the mechanisms underlying eQTL effects.     

Increased Drinking following Social Isolation Rearing: Implications for Polydipsia Associated with Schizophrenia

Primary polydipsia, excessive drinking without known medical cause, is especially associated with a diagnosis of schizophrenia. We used animal models of schizophrenia-like symptoms to examine the effects on schedule-induced polydipsia: post-weaning social isolation rearing, subchronic MK-801 treatment (an NMDA-receptor antagonist) or the two combined. Male, Sprague-Dawley rats reared in groups or in isolation beginning at postnatal day 21 were further divided to receive subchronic MK-801 (0.5 mg/kg twice daily) or saline for 7 days beginning on postnatal day 62. Following a 4-day withdrawal period, all groups were trained on a schedule-induced polydipsia paradigm. Under food-restriction, animals reared in isolation and receiving food pellets at 1-min intervals developed significantly more drinking behavior than those reared with others. The addition of subchronic MK-801 treatment did not significantly augment the amount of water consumed. These findings suggest a predisposition to polydipsia is a schizophrenia-like behavioral effect of post-weaning social isolation.     

Symptoms Associated with Victimization in Patients with Schizophrenia and Related Disorders

Background

Patients with psychoses have an increased risk of becoming victims of violence. Previous studies have suggested that higher symptom levels are associated with a raised risk of becoming a victim of physical violence. There has been, however, no evidence on the type of symptoms that are linked with an increased risk of recent victimization.

Methods

Data was taken from two studies on involuntarily admitted patients, one national study in England and an international one in six other European countries. In the week following admission, trained interviewers asked patients whether they had been victims of physical violence in the year prior to admission, and assessed symptoms on the Brief Psychiatric Rating Scale (BPRS). Only patients with a diagnosis of schizophrenia or related disorders (ICD-10 F20–29) were included in the analysis which was conducted separately for the two samples. Symptom levels assessed on the BPRS subscales were tested as predictors of victimization. Univariable and multivariable logistic regression models were fitted to estimate adjusted odds ratios.

Results

Data from 383 patients in the English sample and 543 patients in the European sample was analysed. Rates of victimization were 37.8% and 28.0% respectively. In multivariable models, the BPRS manic subscale was significantly associated with victimization in both samples.

Conclusions

Higher levels of manic symptoms indicate a raised risk of being a victim of violence in involuntary patients with schizophrenia and related disorders. This might be explained by higher activity levels, impaired judgement or poorer self-control in patients with manic symptoms. Such symptoms should be specifically considered in risk assessments.     

Evidence for a microRNA expansion in the bilaterian ancestor

Understanding how animal complexity has arisen and identifying the key genetic components of this process is a central goal of evolutionary developmental biology. The discovery of microRNAs (miRNAs) as key regulators of development has identified a new set of candidates for this role. microRNAs are small noncoding RNAs that regulate tissue-specific or temporal gene expression through base pairing with target mRNAs. The full extent of the evolutionary distribution of miRNAs is being revealed as more genomes are scrutinized. To explore the evolutionary origins of metazoan miRNAs, we searched the genomes of diverse animals occupying key phylogenetic positions for homologs of experimentally verified human, fly, and worm miRNAs. We identify 30 miRNAs conserved across bilaterians, almost double the previous estimate. We hypothesize that this larger than previously realized core set of miRNAs was already present in the ancestor of all Bilateria and likely had key roles in allowing the evolution of diverse specialist cell types, tissues, and complex morphology. In agreement with this hypothesis, we found only three, conserved miRNA families in the genome of the sea anemone Nematostella vectensis and no convincing family members in the genome of the demosponge Reniera sp. The dramatic expansion of the miRNA repertoire in bilaterians relative to sponges and cnidarians suggests that increased miRNA-mediated gene regulation accompanied the emergence of triploblastic organ-containing body plans. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.     

Genetic Alterations at Chromosome 6 Associated with Cervical Cancer Progression

Loss of heterozygosity (LOH) analysis on chromosome 6 was performed to define the genetic changes that occur in the development of squamous cell cervical cancer (SCC). Detailed analysis with 28 microsatellite markers revealed several loci with high frequency of deletions at the short (6p25, 6p22, 6p21.3) and long (6q14, 6q16–q21, 6q23–q24, 6q25, 6q27) arms of chromosome 6. Examination of microdissected 37 SCC and 22 cervical intraepithelial neoplasias (CIN) revealed allelic deletions in the HLA class I–III region (6p22–p21.3) and at subtelomeric locus 6p25-ter in more than 40% of CIN. By a combination of LOH and microdissection of multiple samples from the same tumor sections, we studied the intratumoral genetic heterogeneity of SCC, and identified clonal and subclonal allelic deletions. Half of SCC had clonal allelic deletion at D6S273, which is localized in intron of Ly6G6D (MEGT1) gene mapped in the HLA class III region. The LOH frequency at 6q in CIN cases did not exceed 20%. Allelic deletions at two loci, 6q14 and 6q16–q21, were for the first time associated with invasion and metastasis in SCC.     

Molecular and Cellular Evidence for an Oligodendrocyte Abnormality in Schizophrenia

Our previous analyses in postmortem prefrontal cortex samples from a well-characterized cohort of severely affected schizophrenics and in matched controls demonstrated decreased expression of myelin and oligodendrocyte-related genes in the disease state. This decreased expression, now replicated in independent studies, suggests that there is a disruption of oligodendrocyte function and/or a loss of oligodendrocytes in schizophrenia. In the current report, we review expression studies in schizophrenia and present data demonstrating consistently fewer oligodendrocytes in schizophrenics compared to controls. The decrease in density reached 22% (p < 0.01) in layer III of area 9 and 20% (p < 0.02) in the white matter of the superior frontal gyrus. These data, when taken together with expression studies carried out by us and by other groups, and by imaging and other microscopic studies, point to a major involvement of oligodendrocyte abnormalities in schizophrenia. Therapies modulating oligodendrocyte survival and differentiation may therefore be beneficial in schizophrenia.     

Sequence-Specific Fidelity Alterations Associated with West Nile Virus Attenuation in Mosquitoes

High rates of error-prone replication result in the rapid accumulation of genetic diversity of RNA viruses. Recent studies suggest that mutation rates are selected for optimal viral fitness and that modest variations in replicase fidelity may be associated with viral attenuation. Arthropod-borne viruses (arboviruses) are unique in their requirement for host cycling and may necessitate substantial genetic and phenotypic plasticity. In order to more thoroughly investigate the correlates, mechanisms and consequences of arbovirus fidelity, we selected fidelity variants of West Nile virus (WNV; Flaviviridae, Flavivirus) utilizing selection in the presence of a mutagen. We identified two mutations in the WNV RNA-dependent RNA polymerase associated with increased fidelity, V793I and G806R, and a single mutation in the WNV methyltransferase, T248I, associated with decreased fidelity. Both deep-sequencing and in vitro biochemical assays confirmed strain-specific differences in both fidelity and mutational bias. WNV fidelity variants demonstrated host-specific alterations to replicative fitness in vitro, with modest attenuation in mosquito but not vertebrate cell culture. Experimental infections of colonized and field populations of Cx. quinquefaciatus demonstrated that WNV fidelity alterations are associated with a significantly impaired capacity to establish viable infections in mosquitoes. Taken together, these studies (i) demonstrate the importance of allosteric interactions in regulating mutation rates, (ii) establish that mutational spectra can be both sequence and strain-dependent, and (iii) display the profound phenotypic consequences associated with altered replication complex function of flaviviruses.     

Investigating Thought Disorder in Schizophrenia: Evidence for Pathological Activation

Background

Previous research has yielded evidence for enhanced semantic priming in formal thought-disordered schizophrenia patients, a result that fits well with the hypothesis of disinhibited processes of spreading activation in this population.

Objective

The current study examined whether hyper priming among schizophrenia patients is an outcome of further spreading of activation of a node or a result of farther activation of nodes in the semantic network. We also try to shed light on the fate of this activation.

Methods

The present study tested this hypothesis by using semantic and identical priming in two different experiments. SOA (stimulus onset asynchrony) was manipulated (240 ms vs. 740 ms) within block. It is assumed that among healthy individuals, performance relies on a balance between activation and inhibition processes, contrary to in schizophrenic individuals. In order to examine this hypothesis, we compared formal thought-disordered schizophrenia patients, non thought-disordered schizophrenia patients, and healthy controls.

Results

For thought-disordered schizophrenia patients, we found a large positive semantic effect and identical priming effect (129 ms and 154 ms, respectively) only with short SOA. SOA and type of priming did not modulate priming effects in the control groups.

Conclusions

This result supports the claim that there is a lack of inhibitory processes among thought-disordered patients. Hyper priming in the thought-disorder group may be an outcome of hyper activation followed by rapid decay below baseline threshold.     

Factors Associated with Medication Adherence among Patients with Schizophrenia in Mekelle,Northern Ethiopia

Background

Non-adherence to antipsychotic medication has a negative impact on the course of illness resulting in increased risk of relapse, rehospitalization and suicide, and increased costs to healthcare systems. The objective of this study was to investigate factors associated with medication adherence among patients with schizophrenia at Ayder Referral Hospital and Mekelle Hospital in Mekelle, Tigray region, Northern Ethiopia.

Methods

The study was a cross-sectional survey in which sociodemographic characteristics, drug attitudes, insight and side effects were measured and explored in terms of their relationship with medication adherence. A structured questionnaire as a data collection tool was used. Data were analyzed with the help of SPSS Version 20.0.

Results

A total of 393 patients participated, 26.5% were non-adherent to their antipsychotic medication. The factors significantly associated with better adherence were positive treatment attitudes (AOR = 1.40, 95% CI: 1.26, 1.55), fewer side effects (AOR = 0.97, 95% CI: 0.94, 0.99), awareness of illness (AOR = 1.44, 95% CI: 1.12, 1.85) and the ability to relabel symptoms (AOR = 1.57, 95% CI: 1.19, 2.07). However, khat chewers (AOR = 0.24, 95% CI: 0.09, 0.68), being illiterate (AOR = 0.13, 95% CI: 0.03, 0.47) and older age group (AOR = 0.03, 95% CI: 0.01, 0.16) were associated with less medication adherence.

Conclusions

A high prevalence of medication non-adherence was found among patients with schizophrenia. Intervention strategies focused on educating the patients to better understand the illness, medications and their potential side effects might be useful in improving adherence to antipsychotic medication treatment.     

Case Report: Genetic Alterations Associated with the Progression of Carotid Paraganglioma

Paragangliomas (PGLs) are rare neuroendocrine tumors that can develop from any paraganglion across the body. The carotid body is the most often location of PGLs in the head and neck region. Carotid PGLs (CPGLs) are characterized by predominantly non-aggressive behavior; however, all tumors have the potential to metastasize. To date, molecular mechanisms of paraganglioma progression remain elusive. We report a case of a 38-year-old woman with metastatic CPGL manifesting as a recurrent tumor with lymph node metastasis. The tumor was fast-growing and had a high Ki-67 proliferation index. Immunohistochemical (IHC) examination and whole-exome sequencing were performed for both recurrent tumor and metastasis. A germline pathogenic splice acceptor variant in the SDHB gene was found in the patient. Immunoreactivity of the SDHB subunit was weak diffuse in both samples, indicating deficiency of the succinate dehydrogenase. Moreover, the recurrent tumor exhibited loss of heterozygosity (LOH) at the SDHB locus, that is according to Knudson’s "two-hit" hypothesis of cancer causation. We also identified a rare somatic promotor mutation in the TERT gene associated with the tumor progression. Obtained results confirmed the indicative role of the germline SDHB mutation for metastatic CPGLs, as well as the potential prognostic value of the TERT promoter mutation.     

Alterations in mRNA Translation Products Associated with Regenerative Responses in the Retina

Translation products of mRNA from retinas of goldfish optic nerve (representing a regenerative CNS) and adult rabbit optic nerve (representing a nonregenerative CNS which can be induced to express regenerative characteristics) were examined by one- and two-dimensional gel electrophoresis. Translation products from retinas of the regenerating goldfish optic nerve included polypeptides barely detectable in the translation products of mRNA derived from retinas of uninjured controls. Some of these polypeptides, of apparent molecular weights 24-28, 43-49, 60, and 65 kilodaltons can be considered as growth-associated polypeptides described in other regenerative and developing systems. The induction of regeneration-associated characteristics in the injured adult rabbit optic nerve, "implanted" with diffusible substances from nonneuronal cells of regenerative or growing nerve, is reflected by changes in the mRNA translation products of the retina. Among such translation products are those of the following molecular weights: 16-18, 28, 32-35, 43-47, and 56-60 kilodaltons, and some higher-molecular-weight species.     

Fecal Protease Activity Is Associated with Compositional Alterations in the Intestinal Microbiota

Objective

Intestinal proteases carry out a variety of functions in the gastrointestinal (GI) tract. Studies have reported that elevated enteric proteases in patients with GI disease can alter intestinal physiology, however the origin (human vs. microbial) of elevated proteases in patients with GI disease is unclear.

Aim

The aim of this study was to investigate the association between protease activity and the microbiota in human fecal samples.

Design

In order to capture a wide range of fecal protease (FP) activity stool samples were collected from 30 IBS patients and 24 healthy controls. The intestinal microbiota was characterized using 454 high throughput pyro-sequencing of the 16S rRNA gene. The composition and diversity of microbial communities were determined and compared using the Quantitative Insights Into Microbial Ecology (QIIME) pipeline. FP activity levels were determined using an ELISA-based method. FP activity was ranked and top and bottom quartiles (n=13 per quartile) were identified as having high and low FP activity, respectively.

Results

The overall diversity of the intestinal microbiota displayed significant clustering separation (p = 0.001) between samples with high vs. low FP activity. The Lactobacillales, Lachnospiraceae, and Streptococcaceae groups were positively associated with FP activity across the entire study population, whilst the Ruminococcaceae family and an unclassified Coriobacteriales family were negatively associated with FP activity.

Conclusions

These data demonstrate significant associations between specific intestinal bacterial groups and fecal protease activity and provide a basis for further causative studies investigating the role of enteric microbes and GI diseases.     

Maternal Obesity Is Associated with Alterations in the Gut Microbiome in Toddlers

Children born to obese mothers are at increased risk for obesity, but the mechanisms behind this association are not fully delineated. A novel possible pathway linking maternal and child weight is the transmission of obesogenic microbes from mother to child. The current study examined whether maternal obesity was associated with differences in the composition of the gut microbiome in children in early life. Fecal samples from children 18–27 months of age (n = 77) were analyzed by pyro-tag 16S sequencing. Significant effects of maternal obesity on the composition of the gut microbiome of offspring were observed among dyads of higher socioeconomic status (SES). In the higher SES group (n = 47), children of obese (BMI≥30) versus non-obese mothers clustered on a principle coordinate analysis (PCoA) and exhibited greater homogeneity in the composition of their gut microbiomes as well as greater alpha diversity as indicated by the Shannon Diversity Index, and measures of richness and evenness. Also in the higher SES group, children born to obese versus non-obese mothers had differences in abundances of Faecalibacterium spp., Eubacterium spp., Oscillibacter spp., and Blautia spp. Prior studies have linked some of these bacterial groups to differences in weight and diet. This study provides novel evidence that maternal obesity is associated with differences in the gut microbiome in children in early life, particularly among those of higher SES. Among obese adults, the relative contribution of genetic versus behavioral factors may differ based on SES. Consequently, the extent to which maternal obesity confers measureable changes to the gut microbiome of offspring may differ based on the etiology of maternal obesity. Continued research is needed to examine this question as well as the relevance of the observed differences in gut microbiome composition for weight trajectory over the life course.     

Integrated Multimodal Imaging of Dynamic Bone-Tumor Alterations Associated with Metastatic Prostate Cancer

Bone metastasis occurs for men with advanced prostate cancer which promotes osseous growth and destruction driven by alterations in osteoblast and osteoclast homeostasis. Patients can experience pain, spontaneous fractures and morbidity eroding overall quality of life. The complex and dynamic cellular interactions within the bone microenvironment limit current treatment options thus prostate to bone metastases remains incurable. This study uses voxel-based analysis of diffusion-weighted MRI and CT scans to simultaneously evaluate temporal changes in normal bone homeostasis along with prostate bone metatastsis to deliver an improved understanding of the spatiotemporal local microenvironment. Dynamic tumor-stromal interactions were assessed during treatment in mouse models along with a pilot prospective clinical trial with metastatic hormone sensitive and castration resistant prostate cancer patients with bone metastases. Longitudinal changes in tumor and bone imaging metrics during delivery of therapy were quantified. Studies revealed that voxel-based parametric response maps (PRM) of DW-MRI and CT scans could be used to quantify and spatially visualize dynamic changes during prostate tumor growth and in response to treatment thereby distinguishing patients with stable disease from those with progressive disease (p<0.05). These studies suggest that PRM imaging biomarkers are useful for detection of the impact of prostate tumor-stromal responses to therapies thus demonstrating the potential of multi-modal PRM image-based biomarkers as a novel means for assessing dynamic alterations associated with metastatic prostate cancer. These results establish an integrated and clinically translatable approach which can be readily implemented for improving the clinical management of patients with metastatic bone disease.

Trial Registration

ClinicalTrials.gov NCT02064283