Proteomic and cytokine plasma biomarkers for predicting progression from colorectal adenoma to carcinoma in human patients

In the present study, we screened proteomic and cytokine biomarkers between patients with adenomatous polyps and colorectal cancer (CRC) in order to improve our understanding of the molecular mechanisms behind turmorigenesis and tumor progression in CRC. To this end, we performed comparative proteomic analysis of plasma proteins using a combination of 2DE and MS as well as profiled differentially regulated cytokines and chemokines by multiplex bead analysis. Proteomic analysis identified 11 upregulated and 13 downregulated plasma proteins showing significantly different regulation patterns with diagnostic potential for predicting progression from adenoma to carcinoma. Some of these proteins have not previously been implicated in CRC, including upregulated leucine‐rich α‐2‐glycoprotein, hemoglobin subunit β, Ig α‐2 chain C region, and complement factor B as well as downregulated afamin, zinc‐α‐2‐glycoprotein, vitronectin, and α‐1‐antichymotrypsin. In addition, plasma levels of three cytokines/chemokines, including interleukin‐8, interferon gamma‐induced protein 10, and tumor necrosis factor α, were remarkably elevated in patients with CRC compared to those with adenomatous polyps. Although further clinical validation is required, these proteins and cytokines can be established as novel biomarkers for CRC and/or its progression from colon adenoma.     

Adipose Vascular Endothelial Growth Factor Regulates Metabolic Homeostasis through Angiogenesis

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Highlights? Two-way modulations of adipose VEGF were generated with aP2-Cre transgene ? Adipose VEGF KO reduces vasculature, increases hypoxia and inflammation in fat ? Adipose VEGF KO accelerates the development of metabolic disease in high-fat diet ? Induced adipose VEGF has opposite effect on fat and restores metabolic homeostasis     

Crif1 Deficiency Reduces Adipose OXPHOS Capacity and Triggers Inflammation and Insulin Resistance in Mice

Impaired mitochondrial oxidative phosphorylation (OXPHOS) has been proposed as an etiological mechanism underlying insulin resistance. However, the initiating organ of OXPHOS dysfunction during the development of systemic insulin resistance has yet to be identified. To determine whether adipose OXPHOS deficiency plays an etiological role in systemic insulin resistance, the metabolic phenotype of mice with OXPHOS–deficient adipose tissue was examined. Crif1 is a protein required for the intramitochondrial production of mtDNA–encoded OXPHOS subunits; therefore, Crif1 haploinsufficient deficiency in mice results in a mild, but specific, failure of OXPHOS capacity in vivo. Although adipose-specific Crif1-haploinsufficient mice showed normal growth and development, they became insulin-resistant. Crif1-silenced adipocytes showed higher expression of chemokines, the expression of which is dependent upon stress kinases and antioxidant. Accordingly, examination of adipose tissue from Crif1-haploinsufficient mice revealed increased secretion of MCP1 and TNFα, as well as marked infiltration by macrophages. These findings indicate that the OXPHOS status of adipose tissue determines its metabolic and inflammatory responses, and may cause systemic inflammation and insulin resistance.     

The N-end rule proteolytic system in autophagy

The N-end rule pathway is a cellular proteolytic system that utilizes specific N-terminal residues as degradation determinants, called N-degrons. N-degrons are recognized and bound by specific recognition components (N-recognins) that mediate polyubiquitination of low-abundance regulators and selective proteolysis through the proteasome. Our earlier work identified UBR4/p600 as one of the N-recognins that promotes N-degron-dependent proteasomal degradation. In this study, we show that UBR4 is associated with cellular cargoes destined to autophagic vacuoles and is degraded by the lysosome. UBR4 loss causes multiple misregulations in autophagic pathways, including an increased formation of LC3 puncta. UBR4-deficient mice die during embryogenesis primarily due to defective vascular development in the yolk sac (YS), wherein UBR4 is associated with a bulk lysosomal degradation system that absorbs maternal proteins from the YS cavity and digests them into amino acids. Our results suggest that UBR4 plays a role not only in selective proteolysis of short-lived regulators through the proteasome, but also bulk degradation through the lysosome. Here, we discuss a possible mechanism of UBR4 as a regulatory component in the delivery of cargoes destined to interact with the autophagic core machinery.     

Structural alteration of Escherichia coli Hsp31 by thermal unfolding increases chaperone activity

Escherichia coli Hsp31, encoded by hchA, is a heat-inducible molecular chaperone. We found that Hsp31 undergoes a conformational change via temperature-induced unfolding, generating a high molecular weight (HMW) form with enhanced chaperone activity. Although it has previously been reported that some subunits of the Hsp31 crystal structure show structural heterogeneity with increased hydrophobic surfaces, Hsp31 basically forms a dimer. We found that a C-terminal deletion (CΔ19) of Hsp31 exhibited structurally and functionally similar characteristics to that of the HMW form. Both the CΔ19 and HMW forms achieved a structure with considerably more β-sheets and less α-helices than the native dimeric form, exposing a portion of its hydrophobic surfaces. The structural alterations were determined from its spectral changes in circular dichroism, intrinsic fluorescence of tryptophan residues, and fluorescence of bis-ANS binding to a hydrophobic surface. Interestingly, during thermal transition, the dimeric Hsp31 undergoes a conformational change to the HMW species via the CΔ19 structure, as monitored with near-UV CD spectrum, implying that the CΔ19 resembles an intermediate state between the dimer and the HMW form. From these results, we propose that Hsp31 transforms itself into a fully functional chaperone by altering its tertiary and quaternary structures.     

Resveratrol Confers Protection against Rotenone-Induced Neurotoxicity by Modulating Myeloperoxidase Levels in Glial Cells

Myeloperoxidase (MPO) functions as a key molecular component of the host defense system against diverse pathogens. We have previously reported that increased MPO levels and activity is a distinguishing feature of rotenone-exposed glial cells, and that either overactivation or deficiency of MPO leads to pathological conditions in the brain. Here, we provide that modulation of MPO levels in glia by resveratrol confers protective effects on rotenone-induced neurotoxicity. We show that resveratrol significantly reduced MPO levels but did not trigger abnormal nitric oxide (NO) production in microglia and astrocytes. Resveratrol-induced down-regulation of MPO, in the absence of an associated overproduction of NO, markedly attenuated rotenone-triggered inflammatory responses including phagocytic activity and reactive oxygen species production in primary microglia and astrocytes. In addition, impaired responses of primary mixed glia from Mpo ^−/− mice to rotenone were relieved by treatment with resveratrol. We further show that rotenone-induced neuronal injury, particularly dopaminergic cell death, was attenuated by resveratrol in neuron-glia co-cultures, but not in neurons cultured alone. Similar regulatory effects of resveratrol on MPO levels were observed in microglia treated with MPP⁺, another Parkinson’s disease-linked neurotoxin, supporting the beneficial effects of resveratrol on the brain. Collectively, our findings provide that resveratrol influences glial responses to rotenone by regulating both MPO and NO, and thus protects against rotenone-induced neuronal injury.     

Association between Depressive Symptoms and Bone Stiffness Index in Young Adults: The Kangwha Study

Objective

Young adulthood is an important period for both bone and mental health. This study investigated the association between depressive symptoms and bone density in apparently healthy Korean men and women aged 29−32 years.

Methods

This study is a cross-sectional analysis of data from 123 men and 133 women who completed follow-up examinations of the Kangwha study in 2010−2011. Bone stiffness index (SI) was measured at the os calcis using a quantitative ultrasound device. Depressive symptoms were evaluated using the Korean version of the Beck Depression Inventory (K-BDI) and classified as normal (K-BDI <10), mild (K-BDI 10–15), and moderate to severe (K-BDI ≥16).

Results

Moderate to severe depressive symptoms were prevalent among 11.4% of men and 19.6% of women. Higher K-BDI scores were significantly correlated to SI in men, before (ρ = –0.286, p = 0.001) and after (ρ = –0.228, p = 0.013) adjustment for covariates. Men with depressive symptoms tended to have a lower SI; multivariate-adjusted mean SI in men with normal, mild, and moderate to severe depressive symptoms was 104.1±3.1, 100.9±5.9, and 94.1±7.8, respectively (p for trend = 0.021). In contrast, no significant correlations were identified in women.

Conclusions

Depressive symptoms were significantly associated with lower SI in men, but not in women. Further studies are necessary to evaluate the impact of depression on developing osteoporosis or osteoporotic fractures later in life.     

Contrasting Phylogeography of Sandy vs. Rocky Supralittoral Isopods in the Megadiverse and Geologically Dynamic Gulf of California and Adjacent Areas

Phylogeographic studies of animals with low vagility and restricted to patchy habitats of the supralittoral zone, can uncover unknown diversity and shed light on processes that shaped evolution along a continent’s edge. The Pacific coast between southern California and central Mexico, including the megadiverse Gulf of California, offers a remarkable setting to study biological diversification in the supralittoral. A complex geological history coupled with cyclical fluctuations in temperature and sea level provided ample opportunities for diversification of supralittoral organisms. Indeed, a previous phylogeographic study of Ligia, a supralittoral isopod that has limited dispersal abilities and is restricted to rocky patches, revealed high levels of morphologically cryptic diversity. Herein, we examined phylogeographic patterns of Tylos, another supralittoral isopod with limited dispersal potential, but whose habitat (i.e., sandy shores) appears to be more extensive and connected than that of Ligia. We conducted Maximum Likelihood and Bayesian phylogenetic analyses on mitochondrial and nuclear DNA sequences. These analyses revealed multiple highly divergent lineages with discrete regional distributions, despite the recognition of a single valid species for this region. A traditional species-diagnostic morphological trait distinguished several of these lineages. The phylogeographic patterns of Tylos inside the Gulf of California show a deep and complex history. In contrast, patterns along the Pacific region between southern California and the Baja Peninsula indicate a recent range expansion, probably postglacial and related to changes in sea surface temperature (SST). In general, the phylogeographic patterns of Tylos differed from those of Ligia. Differences in the extension and connectivity of the habitats occupied by Tylos and Ligia may account for the different degrees of population isolation experienced by these two isopods and their contrasting phylogeographic patterns. Identification of divergent lineages of Tylos in the study area is important for conservation, as some populations are threatened by human activities.     

SARNP,a participant in mRNA splicing and export,negatively regulates E-cadherin expression via interaction with pinin

Triple-negative breast cancer (TNBC) is associated with a high mortality rate, which is related to the insufficient number of appropriate biomarkers and targets. Therefore, there is an urgent need to discover appropriate biomarkers and targets for TNBC. SARNP (Hcc-1 and CIP29) is highly expressed in several cancers. It binds to UAP56, an RNA helicase component of the TREX complex in messenger RNA (mRNA) splicing and export. However, the role of SARNP in mRNA splicing and export and in the progression of breast cancer, especially of TNBC, remains unknown. Therefore, we examined the role of SARNP in mRNA splicing and export and progression of TNBC. We confirmed that SARNP binds to UAP56 and Aly and that SARNP overexpression enhances mRNA splicing, whereas its knockdown suppressed mRNA export. The SARNP overexpression induced the proliferation of MCF7 cells, whereas its knockdown induced E-cadherin expression and downregulated vimentin and N-cadherin expressions in SK-BR-3 and MDA-MB-231 cells. SARNP downregulates E-cadherin expression by interaction with pinin. Mice injected with MDA-MB-231_shSARNP cells exhibited a significant reduction in tumor growth and lung metastasis compared with those injected with MDA-MB-231_shCon cells in vivo. These findings suggested that SARNP is involved in mRNA splicing and export. SARNP maintains mesenchymal phenotype by escaping from inhibitory interaction with pinin leading to the downregulation of E-cadherin expression.