Administration of Hepatocyte Growth Factor Increases Reelin and Disabled 1 Expression in the Mouse Cerebral Cortex: An In Vivo Study

Hepatocyte growth factor (HGF) and its receptor, c-Met, are widely expressed in the developing brain. HGF also known as scatter factor enhances cell proliferation and cell growth, and stimulates cell migration and motility. Neurons and glia produced in the neuroepithelium migrate along radial glial fibers into the cortical plate. Reelin, a glycoprotein which is produced by Cajal–Retzius cells in the marginal zone directs neuronal migration indirectly via the radial glial cells. It has been demonstrated that Disabled 1 functions downstream of reelin in a tyrosin kinase signal transduction pathway that controls appropriate cell positioning in the developing brain. In this study, administration of HGF on reelin and Disabled 1 expression in the cerebral cortex has been studied. Using Western blot, it was shown that the expression of reelin and Disabled 1 is increased in response to infusion of HGF when compared to control group. It is concluded that HGF is essential for reelin and Disabled 1 expression in the cerebral cortex of the newborn mouse. Moreover, this method may be applied to the other factors, allowing identification of molecules involved in neural cell migration.     

Macromixing hydrodynamic study in draft-tube airlift reactors using electrical resistance tomography

The present study summarizes results of mixing characteristics in a draft tube airlift bioreactor using ERT. This technique offers the possibility for noninvasive and nonintrusive visualization of flow fields in the bioreactor and has rarely been utilized previously to analyze operating parameters and mixing characteristics in this type of bioreactors. Several operating parameters and geometric characteristics were examined. In general, results showed that the increase in superficial gas velocity corresponds to an increase in energy applied and thus, to a decrease in mixing time. This generally corresponded to an increase in liquid circulation velocity and shear rate values. Bottom clearances and draft tube diameters affected flow resistance and frictional losses. The influence of sparger configurations on mixing time and liquid circulation velocity was significant due to their effect on gas distribution. However, the effect of sparger configuration on shear rate was not significant, with 20% reduction in shear rates using the cross-shaped sparger. Fluid viscosity showed a marked influence on both mixing times and circulation velocity especially in the coalescing media of sugar and xanthan gum (XG) solutions. Results from this work will help to develop a clear pattern for operation and mixing that can help to improve several industrial processes, especially the ones related to emerging fields of technology such as the biotechnology industry.     

Diabetes mellitus and its correlates in an Iranian adult population

The rising epidemic of diabetes imposes a substantial economic burden on the Middle East. Using baseline data from a population based cohort study, we aimed to identify the correlates of diabetes mellitus (DM) in a mainly rural population from Iran. Between 2004 and 2007, 50044 adults between 30 and 87 years old from Golestan Province located in Northeast Iran were enrolled in the Golestan Cohort Study. Demographic and health-related information was collected using questionnaires. Individuals' body sizes at ages 15 and 30 were assessed by validated pictograms ranging from 1 (very lean) to 7 in men and 9 in women. DM diagnosis was based on the self-report of a physician's diagnosis. The accuracy of self-reported DM was evaluated in a subcohort of 3811 individuals using fasting plasma glucose level and medical records. Poisson regression with robust variance estimator was used to estimate prevalence ratios (PR's). The prevalence of self-reported DM standardized to the national and world population was 5.7% and 6.2%, respectively. Self-reported DM had 61.5% sensitivity and 97.6% specificity. Socioeconomic status was inversely associated with DM prevalence. Green tea and opium consumption increased the prevalence of DM. Obesity at all ages and extreme leanness in childhood increased diabetes prevalence. Being obese throughout life doubled DM prevalence in women (PR: 2.1; 95% CI: 1.8, 2.4). These findings emphasize the importance of improving DM awareness, improving general living conditions, and early lifestyle modifications in diabetes prevention.     

Human primary adipocytes exhibit immune cell function: adipocytes prime inflammation independent of macrophages

Background

Obesity promotes inflammation in adipose tissue (AT) and this is implicated in pathophysiological complications such as insulin resistance, type 2 diabetes and cardiovascular disease. Although based on the classical hypothesis, necrotic AT adipocytes (ATA) in obese state activate AT macrophages (ATM) that then lead to a sustained chronic inflammation in AT, the link between human adipocytes and the source of inflammation in AT has not been in-depth and systematically studied. So we decided as a new hypothesis to investigate human primary adipocytes alone to see whether they are able to prime inflammation in AT.

Methods and Results

Using mRNA expression, human preadipocytes and adipocytes express the cytokines/chemokines and their receptors, MHC II molecule genes and 14 acute phase reactants including C-reactive protein. Using multiplex ELISA revealed the expression of 50 cytokine/chemokine proteins by human adipocytes. Upon lipopolysaccharide stimulation, most of these adipocyte-associated cytokines/chemokines and immune cell modulating receptors were up-regulated and a few down-regulated such as (ICAM-1, VCAM-1, MCP-1, IP-10, IL-6, IL-8, TNF-α and TNF-β highly up-regulated and IL-2, IL-7, IL-10, IL-13 and VEGF down-regulated. In migration assay, human adipocyte-derived chemokines attracted significantly more CD4+ T cells than controls and the number of migrated CD4+ cells was doubled after treating the adipocytes with LPS. Neutralizing MCP-1 effect produced by adipocytes reduced CD4+ migration by approximately 30%.

Conclusion

Human adipocytes express many cytokines/chemokines that are biologically functional. They are able to induce inflammation and activate CD4+ cells independent of macrophages. This suggests that the primary event in the sequence leading to chronic inflammation in AT is metabolic dysfunction in adipocytes, followed by production of immunological mediators by these adipocytes, which is then exacerbated by activated ATM, activation and recruitment of immune cells. This study provides novel knowledge about the prime of inflammation in human obese adipose tissue, opening a new avenue of investigations towards obesity-associated type 2 diabetes.     

Effects of Zinc Supplementation on Physical Growth in 2–5-Year-Old Children

Physical growth disorders in under 5-year-old children are a common health problem in many countries including Iran. The aim of this study was to determine effects of supplemental zinc on physical growth in preschool children with retarded linear growth. This study was a community-based randomized controlled trial on 2–5-year-old children with height-for-age below 25th percentile of National Center for Health Statistics growth chart. Ninety children were randomly assigned in zinc group (ZG) or placebo group (PG). After 6 months of zinc or placebo supplementation, we followed up the children for another 6 months. Anthropometric indicators were measured before the intervention and then monthly for 11 months. Forty children in ZG and 45 in PG concluded the study. Zinc supplementation increased weight gain in boys (P = 0.04) and girls (P = 0.05) compared to placebo but had no significant effect on mid-upper arm circumference increment in either sexes. The most significant (P = 0.001) effect of Zinc supplementation was seen in boys’ height increment at the end of follow-up period. Stunted growth rate in ZG changed significantly (P = 0.01) from 26.7% to 2.5% throughout the study. This study showed that daily supplementation of 5 mg elemental zinc for 6 months improves physical growth in terms of height increment and weight gain in children with undesirable linear growth, especially in boys.     

Induction of lactoferrin gene expression by innate immune stimuli in mouse mammary epithelial HC-11 cells

Lactoferrin (LF) is a multifunctional protein. While its functions and mechanism of actions are actively being investigated, the cellular signals that regulate LF expression have not been as explored. We have previously demonstrated that LF is upregulated by estrogen in the reproductive system. In this study, we show that the expression of LF was stimulated by bacterial lipopolysaccharide (LPS) and double-stranded RNA (dsRNA) in normal mouse mammalian HC-11 cells. When cells were exposed to either LPS or dsRNA, the mRNA and protein of LF were increased in a dose- and time-dependent manner, yet the kinetics of LF induction by dsRNA or LPS were different. The LPS and dsRNA-induced LF was mainly released into the culture medium where it blocked TNF-alpha production in exposed cells. We explored the mechanisms of LF induction by LPS and dsRNA using specific inhibitors and found that the induction could be attenuated by inhibitors to PKC, NF-kappaB, p38 and JNK, but not by an inhibitor to PKA. Interestingly, ERK inhibitor was effective against dsRNA but not against LPS induction of LF. These data suggest that LF was induced by LPS and dsRNA through PKC, NF-kappaB and MAPK pathways which in turn play an inhibitory role in the continuation of innate inflammation.     

Editor's Choice: Mate Pair Sequencing of Whole-Genome-Amplified DNA Following Laser Capture Microdissection of Prostate Cancer

High-throughput next-generation sequencing provides a revolutionary platform to unravel the precise DNA aberrations concealed within subgroups of tumour cells. However, in many instances, the limited number of cells makes the application of this technology in tumour heterogeneity studies a challenge. In order to address these limitations, we present a novel methodology to partner laser capture microdissection (LCM) with sequencing platforms, through a whole-genome amplification (WGA) protocol performed in situ directly on LCM engrafted cells. We further adapted current Illumina mate pair (MP) sequencing protocols to the input of WGA DNA and used this technology to investigate large genomic rearrangements in adjacent Gleason Pattern 3 and 4 prostate tumours separately collected by LCM. Sequencing data predicted genome coverage and depths similar to unamplified genomic DNA, with limited repetition and bias predicted in WGA protocols. Mapping algorithms developed in our laboratory predicted high-confidence rearrangements and selected events each demonstrated the predicted fusion junctions upon validation. Rearrangements were additionally confirmed in unamplified tissue and evaluated in adjacent benign-appearing tissues. A detailed understanding of gene fusions that characterize cancer will be critical in the development of biomarkers to predict the clinical outcome. The described methodology provides a mechanism of efficiently defining these events in limited pure populations of tumour tissue, aiding in the derivation of genomic aberrations that initiate cancer and drive cancer progression.     

Genetic and physical fine mapping of the novel brown midrib gene bm6 in maize (Zea mays L.) to a 180?kb region on chromosome 2

Brown midrib mutants in maize are known to be associated with reduced lignin content and increased cell wall digestibility, which leads to better forage quality and higher efficiency of cellulosic biomass conversion into ethanol. Four well known brown midrib (bm) mutants, named bm1-4, were identified several decades ago. Additional recessive brown midrib mutants have been identified by allelism tests and designated as bm5 and bm6. In this study, we determined that bm6 increases cell wall digestibility and decreases plant height. bm6 was confirmed onto the short arm of chromosome 2 by a small mapping set with 181 plants from a F(2) segregating population, derived from crossing B73 and a bm6 mutant line. Subsequently, 960 brown midrib individuals were selected from the same but larger F(2) population for genetic and physical mapping. With newly developed markers in the target region, the bm6 gene was assigned to a 180?kb interval flanked by markers SSR_308337 and SSR_488638. In this region, ten gene models are predicted in the maize B73 sequence. Analysis of these ten genes as well as genes in the syntenic rice region revealed that four of them are promising candidate genes for bm6. Our study will facilitate isolation of the underlying gene of bm6 and advance our understanding of brown midrib gene functions.     

Hedgehog signalling as an antagonist of ageing and its associated diseases

Hedgehog is an important morphogenic signal that directs pattern formation during embryogenesis, but its activity also remains present through adult life. It is now becoming increasingly clear that during the reproductive phase of life and beyond it continues to direct cell renewal (which is essential to combat the chronic environmental stress to which the body is constantly exposed) and counteracts vascular, osteolytic and sometimes oncological insults to the body. Conversely, down-regulation of hedgehog signalling is associated with ageing-related diseases such as type 2 diabetes, neurodegeneration, atherosclerosis and osteoporosis. Hence, in this essay we argue that hedgehog signalling is not only important at the start of life, but also constitutes an important anti-geriatric influence, and that enhanced understanding of its properties may contribute to developing rational strategies for healthy ageing and prevention of ageing-related diseases. Also watch the Video Abstract.     

Possible role of oxidized lipids in osteoporosis: could hyperlipidemia be a risk factor?

Several years ago we hypothesized that products of lipid and lipoprotein oxidation may contribute to pathophysiology of osteoporosis (F. Parhami, Curr. Opin. Lipidol. 8 (1997) 312), and that their effects on artery wall and bone cells may explain the parallel development of osteoporosis and atherosclerosis in the same subjects (R. Boukhris, JAMA 219 (1972) 1307; M.A. Frye, Bone Miner. 19 (1992) 185). Since then, new evidence has accumulated in support of this hypothesis and its possibility is being further tested by investigators in both vascular and bone fields (A.D. Watson, J. Biol. Chem. 272 (1997) 13597). This review will summarize the evidence to date that support the role of oxidized lipids in osteoporosis, and will address some of the issues that need further examination in order to establish whether hyperlipidemia and susceptibility to lipid oxidation may serve as risk factors for osteoporosis.