Metabolic Syndrome Components Are Associated with Intervertebral Disc Degeneration: The Wakayama Spine Study

Objective

The objective of the present study was to examine the associations between metabolic syndrome (MS) components, such as overweight (OW), hypertension (HT), dyslipidemia (DL), and impaired glucose tolerance (IGT), and intervertebral disc degeneration (DD).

Design

The present study included 928 participants (308 men, 620 women) of the 1,011 participants in the Wakayama Spine Study. DD on magnetic resonance imaging was classified according to the Pfirrmann system. OW, HT, DL, and IGT were assessed using the criteria of the Examination Committee of Criteria for MS in Japan.

Results

Multivariable logistic regression analysis revealed that OW was significantly associated with cervical, thoracic, and lumbar DD (cervical: odds ratio [OR], 1.28; 95% confidence interval [CI], 0.92–1.78; thoracic: OR, 1.75; 95% CI, 1.24–2.51; lumbar: OR, 1.87; 95% CI, 1.06–3.48). HT and IGT were significantly associated with thoracic DD (HT: OR, 1.54; 95% CI, 1.09–2.18; IGT: OR, 1.65; 95% CI, 1.12–2.48). Furthermore, subjects with 1 or more MS components had a higher OR for thoracic DD compared with those without MS components (vs. no component; 1 component: OR, 1.58; 95% CI, 1.03–2.42; 2 components: OR, 2.60; 95% CI, 1.62–4.20; ≥3 components: OR, 2.62; 95% CI, 1.42–5.00).

Conclusion

MS components were significantly associated with thoracic DD. Furthermore, accumulation of MS components significantly increased the OR for thoracic DD. These findings support the need for further studies of the effects of metabolic abnormality on DD.     

Post-construction avian mortality monitoring at Project West Wind

Abstract

Post-construction avifauna investigations were undertaken at Project West Wind, Meridian Energy Limited's 62-turbine wind farm on the Wellington south coast. These investigations were required in accordance with the resource consent conditions to quantify the level of avian mortalities occurring at the wind farm, particularly in regard to New Zealand falcon (Falco novaeseelandiae), kākā (Nestor meridionalis) and kererū (Hemiphaga novaeseelandiae). This is the first comprehensive study at a New Zealand operating wind farm. The methods included three field components necessary to calculate annual estimates of mortalities across the wind farm site: routine turbine searches; carcass detection trials; and carcass removal trials. Results from years 1 and 2 of a three-year programme are presented. To date, mortalities have been recorded for 17 taxa at 18 of the 24 study turbines. There have been no recorded mortalities of falcon, kākā or kererū. Australasian harrier (Circus approximans) has been the species for which the most mortalities have been recorded. Overall estimated annual mortality rates for years 1 and 2 were calculated to be approximately six and five birds per turbine respectively.     

Leptin activation of mTOR pathway in intestinal epithelial cell triggers lipid droplet formation,cytokine production and increased cell proliferation

Accumulating evidence suggests that obesity and enhanced inflammatory reactions are predisposing conditions for developing colon cancer. Obesity is associated with high levels of circulating leptin. Leptin is an adipocytokine that is secreted by adipose tissue and modulates immune response and inflammation. Lipid droplets (LD) are organelles involved in lipid metabolism and production of inflammatory mediators, and increased numbers of LD were observed in human colon cancer. Leptin induces the formation of LD in macrophages in a PI3K/mTOR pathway-dependent manner. Moreover, the mTOR is a serine/threonine kinase that plays a key role in cellular growth and is frequently altered in tumors. We therefore investigated the role of leptin in the modulation of mTOR pathway and regulation of lipid metabolism and inflammatory phenotype in intestinal epithelial cells (IEC-6 cells). We show that leptin promotes a dose- and time-dependent enhancement of LD formation. The biogenesis of LD was accompanied by enhanced CXCL1/CINC-1, CCL2/MCP-1 and TGF-β production and increased COX-2 expression in these cells. We demonstrated that leptin-induced increased phosphorylation of STAT3 and AKT and a dose and time-dependent mTORC activation with enhanced phosphorilation of the downstream protein P70S6K protein. Pre-treatment with rapamycin significantly inhibited leptin effects in LD formation, COX-2 and TGF-β production in IEC-6 cells. Moreover, leptin was able to stimulate the proliferation of epithelial cells on a mTOR-dependent manner. We conclude that leptin regulates lipid metabolism, cytokine production and proliferation of intestinal cells through a mechanism largely dependent on activation of the mTOR pathway, thus suggesting that leptin-induced mTOR activation may contribute to the obesity-related enhanced susceptibility to colon carcinoma.     

RanBP9 at the intersection between cofilin and Aβ pathologies: rescue of neurodegenerative changes by RanBP9 reduction

Molecular pathways underlying the neurotoxicity and production of amyloid β protein (Aβ) represent potentially promising therapeutic targets for Alzheimer''s disease (AD). We recently found that overexpression of the scaffolding protein RanBP9 increases Aβ production in cell lines and in transgenic mice while promoting cofilin activation and mitochondrial dysfunction. Translocation of cofilin to mitochondria and induction of cofilin–actin pathology require the activation/dephosphorylation of cofilin by Slingshot homolog 1 (SSH1) and cysteine oxidation of cofilin. In this study, we found that endogenous RanBP9 positively regulates SSH1 levels and mediates Aβ-induced translocation of cofilin to mitochondria and induction of cofilin–actin pathology in cultured cells, primary neurons, and in vivo. Endogenous level of RanBP9 was also required for Aβ-induced collapse of growth cones in immature neurons (days in vitro 9 (DIV9)) and depletion of synaptic proteins in mature neurons (DIV21). In vivo, amyloid precursor protein (APP)/presenilin-1 (PS1) mice exhibited 3.5-fold increased RanBP9 levels, and RanBP9 reduction protected against cofilin–actin pathology, synaptic damage, gliosis, and Aβ accumulation associated with APP/PS1 mice. Brains slices derived from APP/PS1 mice showed significantly impaired long-term potentiation (LTP), and RanBP9 reduction significantly enhanced paired pulse facilitation and LTP, as well as partially rescued contextual memory deficits associated with APP/PS1 mice. Therefore, these results underscore the critical importance of endogenous RanBP9 not only in Aβ accumulation but also in mediating the neurotoxic actions of Aβ at the level of synaptic plasticity, mitochondria, and cofilin–actin pathology via control of the SSH1-cofilin pathway in vivo.The defining pathological hallmark of Alzheimer''s disease (AD) is the accumulation of amyloid β protein (Aβ) in brain associated with tau pathology, synapse loss, cytoskeletal aberrations, mitochondrial dysfunction, and cognitive decline. The generation of Aβ occurs via sequential β- and γ-secretase processing of the amyloid precursor protein (APP) by beta site APP cleaving enzyme 1 (BACE1) and the presenilin (PS) complex, respectively.¹ Soluble oligomeric forms of Aβ are thought to be the most toxic species, resulting in synaptic loss and downstream neurotoxicity.² Despite the requirement for Tau in multiple aspects of Aβ-induced neurotoxicity,³ a large knowledge gap exists as to how the Aβ oligomer-induced neurotoxic signals are transduced intracellularly to impair synaptic plasticity, eventually leading to neurodegeneration. Both Aβ and Tau promote cofilin–actin pathology,^{4, 5} cofilin–actin pathology is widespread in AD brains,⁶ and cofilin activity is also increased in AD brains.⁷ Cofilin normally functions as a key regulator of actin dynamics that destabilizes filamentous actin (F-actin). Cofilin is inactivated by phosphorylation on Ser3 by LIM kinase 1 (LIMK1), whereas its dephosphorylation by Slingshot homolog 1 (SSH1) activates cofilin.⁴ Upon oxidative stress and/or Ca²⁺ elevation,^{4, 8, 9} SSH1 is activated and active cofilin becomes oxidized on cysteine residues, resulting in rapid mitochondrial translocation to promote apoptosis and induction of cofilin–actin pathology.^{10, 11} An early and consistent impairment secondary to Aβ oligomer treatment in primary neurons is the shrinkage of dendritic spines¹² involving the rearrangement of F-actin cytoskeleton in spines and loss of spine-associated proteins such as postsynaptic density-95 (PSD95) and Drebrin,^{13, 14} as well as impaired mitochondrial function.^{15, 16}We recently found that overexpression of the scaffolding protein RanBP9 increases Aβ production in cell lines and in transgenic mice.^{17, 18} Moreover, RanBP9 is significantly increased in brains of AD patients and the J20 APP transgenic model.^{18, 19} In studying the trafficking of APP, we also found that RanBP9 overexpression not only promotes the endocytosis of APP but also those of LRP and β1-integrin, the latter resulting in disassembly of integrin-associated focal complexes (talin and vinculin).²⁰ In addition, RanBP9 overexpression promotes cofilin activation and the translocation of cofilin to mitochondria, resulting in overall mitochondrial dysfunction.^{9, 19} However, how RanBP9 activates cofilin is unknown, and it is not clear whether reduction in endogenous RanBP9 protects against Aβ oligomer-induced deficits in synaptic plasticity, cofilin-dependent pathology, Aβ accumulation, and memory impairment. Here we report that short interfering ribonucleic acid (siRNA) or genetic reduction in RanBP9 significantly reduces SSH1 levels and mitigates Aβ-induced translocation of cofilin to mitochondria, cofilin–actin rod/aggregate formation, depletion of synaptic proteins, deficits in synaptic plasticity, Aβ accumulation, and contextual memory deficits in vivo.     

A filter paper dye-binding assay for quantitative determination of protein without interference from reducing agents or detergents

A method is described for quantitation of protein in the presence of reducing agents, detergents, and other substances which often interfere with assays of protein in solution. The proteins are applied to Whatman No. 1 filter paper, air-dried, washed with methanol, and then stained with Coomassie brilliant blue G. Following destaining, the paper is air-dried and the protein-bound dye is extracted. Sample absorbance measurements are made in a 96-well plate using an automated microplate reader (600-405 nm) or in a cuvette at 610 nm. This filter paper assay is useful for determining 100 ng to 20 micrograms of protein in the presence of ammonium sulfate, urea, thiol-reducing agents, amino acids, DNA, ionic and nonionic detergents, and acid or base.     

Nuclear factor-kappa B localization and function within intrauterine tissues from term and preterm labor and cultured fetal membranes

Background  

The objective of this study was to quantify the nuclear localization and DNA binding activity of p65, the major transactivating nuclear factor-kappa B (NF-kappaB) subunit, in full-thickness fetal membranes (FM) and myometrium in the absence or presence of term or preterm labor.