Transcriptome analysis reveals the potential contribution of long noncoding RNAs to brown adipocyte differentiation.

Brown adipose tissue (BAT) functions to dissipate energy in response to cold exposure or overfeeding. Counteracting obesity has been extensively considered as a promising target. Long noncoding RNAs (lncRNAs) are an important class of pervasive genes involved in a variety of biological functions. However, the potential biological functions of lncRNAs during mouse brown fat cell differentiation have not been fully understood. Here, we performed lncRNA and mRNA expression profile analysis using microarray technology and identified 1064 lncRNAs with differential expression (fold change| ≥4, p ≤ 0.01) on day 0 and day 8 during differentiation. Furthermore, candidate lncRNAs were characterized by comprehensive examination of their genomic context, gene ontology (GO) enrichment of their associated protein-coding genes and pathway analysis. We identified three lncRNAs (Gm15051, Tmem189 and Cebpd) associated with their flanking coding genes (Hoxa1, C/EBPß and C/EBPδ), which participated in adipose commitment. Collectively, our findings indicated lncRNAs are involved in mouse BAT development and provide potential targets for obesity therapy.

The biological effects of hsa-miR-1908 in human adipocytes.

MicroRNAs (miRNAs) are small non-coding RNAs involved in the regulation of gene expression. MiR-1908 is a recently identified miRNA that is highly expressed in human adipocytes. However, it is not known what role of miR-1908 is involved in the regulation of human adipocytes. In this study, we demonstrate that the level of miR-1908 increases during the adipogenesis of human multipotent adipose-derived stem (hMADS) cells and human preadipocytes-visceral. Overexpression of miR-1908 in hMADS cells inhibited adipogenic differentiation and increased cell proliferation, suggesting that miR-1908 is involved in the regulation of adipocyte cell differentiation and metabolism, and, thus, may have an effect on human obesity.

Aberrant hepatic microRNA expression in nonalcoholic fatty liver disease.

BACKGROUND/AIM: Emerging evidence suggests that microRNA (miRNA) mediated gene regulation influences the maintenance of metabolic homeostasis, particularly the states of obesity and insulin resistance, thereby providing a potential link between miRNAs and nonalcoholic fatty liver disease (NAFLD). METHODS: Sprague-Dawley rats fed a high-fat diet (HFD) were used to establish a rat model of NAFLD. The miRNA expression profile of liver tissues was evaluated using Illumina HiSeq deep sequencing. Selected miRNAs were then validated by real-time PCR at both 4- and 12-week time points. Furthermore, the expression levels of these miRNAs were assessed in HepG2 cells and human hepatocytes treated with free fatty acids (FFAs) and proinflammatory factors (tumour necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). RESULTS: Our results showed that consumption of a HFD for 4 weeks caused simple steatosis, which progressed to steatohepatitis at 12 weeks. miRNA deep sequencing analysis identified 44 known up-regulated miRNAs (fold change >1.5) and 12 down-regulated miRNAs (fold change <0.5). Among the abnormally expressed miRNAs, miR-200a, miR-200b, miR-200c, miR-146a, miR-146b and miR-152 were up-regulated both in vitro and vivo. Interestingly, the expression levels of these six miRNAs were increased in HepG2 cells and human hepatocytes after treatment with FFAs and proinflammatory factors. CONCLUSION: These findings suggest a critical role for miRNAs in the pathogenesis of NAFLD.

Peptidome analysis of human skim milk in term and preterm milk.

The abundant proteins in human milk have been well characterized and are known to provide nutritional, protective, and developmental advantages to both term and preterm infants. Due to the difficulties associated with detection technology of the peptides, the expression of the peptides present in human milk is not known widely. In recent years, peptidome analysis has received increasing attention. In this report, the analysis of endogenous peptides in human milk was done by mass spectrometry. A method was also developed by our researchers, which can be used in the extraction of peptide from human milk. Analysis of the extracts by LC-MS/MS resulted in the detection of 1000-3000Da peptide-like features. Out of these, 419 peptides were identified by MS/MS. The identified peptides were found to originate from 34 proteins, of which several have been reported. Analysis of the peptides' cleavage sites showed that the peptides are cleaved with regulations. This may reflect the protease activity and distribution in human body, and also represent the biological state of the tissue and provide a fresh source for biomarker discovery. Isotope dimethyl labeling analysis was also used to test the effects of premature delivery on milk protein composition in this study. Differences in peptides expression between breast milk in term milk (38-41weeks gestation) and preterm milk (28-32weeks gestation) were investigated in this study. 41 Peptides in these two groups were found expressed differently. 23 Peptides were present at higher levels in preterm milk, and 18 were present at higher levels in term milk.

Characterization of microRNA expression profiles in 3T3-L1 adipocytes overexpressing C10orf116.

Our data in the previous report demonstrated that C10orf116 (AFRO) is an adipocyte lineage-specific nuclear factor that can modulate the master adipogenesis transcription factors early during differentiation. However, more precise functional properties of this gene need to be clarified and await further investigation. Therefore, in this study, we performed an expression profile of cellular MicroRNAs (miRNAs) in the C10orf116 overexpression 3T3-L1 adipocytes and performed target prediction and functional enrichment of the differentially expressed miRNAs. Our study identified 34 miRNAs up-regulated in the 3T3-L1 adipocytes stably overexpressing C10orf116, whereas 43 miRNAs up-regulated in the control cells. The target genes of differentially expressed miRNAs were found to be involved in multiple signalling pathways, such as Wnt, TGF-beta, MAPK, Jak-STAT, insulin signalling pathway, et al. Our data provided novel information for the identification of C10orf116.

Increased locomotor activity and non-selective attention and impaired learning ability in SD rats after lentiviral vector-mediated RNA interference of Homer 1a in the brain.

Our previous studies found that Homer 1a, a scaffolding protein localized at the post-synaptic density (PSD) of glutamatergic excitatory synapses, is significantly down-regulated in the brain of spontaneous hypertensive rats (SHR), an animal model of attention deficit hyperactivity disorder (ADHD). Furthermore, a first-line treatment drug for ADHD, methylphenidate, can up-regulate the expression of Homer 1a. To investigate the possible role of Homer 1a in the etiology and pathogenesis of ADHD, a lentiviral vector containing miRNA specific for Homer 1a was constructed in this study. Intracerebroventricular injection of this vector into the brain of Sprague Dawley (SD) rats significantly decreased Homer 1a mRNA and protein expression levels. Compared to their negative controls, these rats displayed a range of abnormal behaviors, including increased locomotor activity and non-selective attention and impaired learning ability. Our results indicated that Homer 1a down-regulation results in deficits in control over behavioral output and learning similar to ADHD.

Anxiety and depression in parents of sick neonates: a hospital-based study.

AIMS AND OBJECTIVES: To investigate the prevalence of anxiety and depression in parents of hospitalised neonates and to analyse their relationship with other factors such as stress and social support, to provide evidence for targeted clinical interventions. BACKGROUND: The perinatal period, a special susceptibility to negative emotions, is a period that women and their spouses have to face. In this time, the fact that the neonates have to be hospitalised is no doubt a huge psychological stress to their parents. Little understanding of the hospitalisation environment, lacking awareness of neonatal diseases as well as concerns about the neonates' safety, can easily lead to negative emotions in parents. Under the influence of negative mood, parents could become irritable and vulnerable, which may do harm to their physical and mental health, impact family harmony and even result in ineffective communication with doctors, affecting the care of neonates. DESIGN: This study applied a cross-sectional study design. METHODS: The psychological status of 600 parents (400 fathers and 200 mothers) was assessed in the first week of the hospitalisation of neonates, using the Self-Rating Anxiety Scale, Self-Rating Depressive Scale, Social Support Rating Scale and Perceived Stress Scale. RESULTS: The results of the cross-sectional survey showed that 20% of fathers and 24% of mothers had symptoms of anxiety, while 30.8% of fathers and 35% of mothers had depressive symptoms. The total scores for anxiety and depression in these parents were significantly higher than the normal population (p<0.01). The level of social support and perceived stress were the most important factors relating to parental anxiety and depression. CONCLUSION: Parents of hospitalised neonates are more prone to suffer from negative emotions than normal population. Anxiety and depression are common emotions in these parents. However, the social support they receive is far from satisfactory, so timely and effective nursing interventions are essential. RELEVANCE TO CLINICAL PRACTICE: Health professionals should understand the mental health of parents with hospitalised neonates and take measures to reduce their psychological pressure so as to improve their care of the neonates, and help to maintain the harmony and stability of families and the whole society.

Blood lead levels during pregnancy and its influencing factors in Nanjing, China.

OBJECTIVE: To investigate the blood lead levels (BLLs) in the duration of pregnancy and 6-12 weeks after delivery, and analyze the influencing factors of BLLs in healthy pregnant women. METHODS: Pregnant women were recruited from September 2009 to February 2010 at the prenatal clinic in Nanjing Maternity and Child Health Care Hospital. Altogether 174 healthy pregnant women without pregnant or obstetric complications or abnormal pregnancy outcomes were enrolled as the gravida group, and 120 healthy non-pregnant women as the control group. BLLs during pregnancy were determined by flame atomic absorption spectroscopy. RESULTS: BLLs in all the three pregnancy trimesters and postpartum were 59.8±24.3, 55.4±20.1, 55.9±19.7, and 67.6±17.4 µg/L, respectively, and the mean BLL in control group was 67.5±21.3 µg/L. BLLs during all the three trimesters were lower in the gravida group than in the control group (P=0.043, 0.021, and 0.028). Furthermore, occupations, nutrients supplementation, and time of house/apartment painted were associated with BLLs in pregnant women. Lead-related occupations, cosmetics use, and living in a house painted less than 1 year before are risk factors of high BLLs among pregnant women, while calcium, iron, zinc, and milk supplements are protective factors. CONCLUSION: Supplementing calcium, iron, zinc, and milk, or avoiding contact with risk factors may help people, especially pregnant women, to reduce lead exposure.

Approaches to addressing the rise in obesity levels.

Levels of obesity and overweight are increasing globally, with affected individuals often experiencing health issues and reduced quality of life. The pathogenesis of obesity is complex and multifactorial, and effective solutions have been elusive. In this Viewpoint, experts in the fields of medical therapy, adipocyte biology, exercise and muscle, bariatric surgery, genetics, and public health give their perspectives on current and future progress in addressing the rising prevalence of obesity.

Effects of Lyrm1 knockdown on mitochondrial function in 3 T3-L1 murine adipocytes.

To explore the effects of Lyrm1 knockdown on the mitochondrial function of 3 T3-L1 adipocytes using small interfering RNA (siRNA). 3 T3-L1 preadipocytes were infected with either a negative control (NC) expression lentivirus or a Lyrm1-shRNA expression lentivirus and induced to differentiate. The knockdown efficiency of Lrym1-specific shRNA in 3 T3-L1 cells was evaluated by real-time PCR. The ultrastructure of the mitochondria in adipocytes was visualized using transmission electron microscopy after differentiation. The levels of mitochondrial DNA copy numbers and Ucp2 mRNA were detected by real-time quantitative PCR. The levels of ATP production was detected using a photon-counting luminometer. The mitochondrial membrane potential and ROS levels of cells were analyzed with a FACScan flow cytometer using Cell Quest software. Cells transfected with lentiviral-Lyrm1-shRNA showed a significantly reduced transcription of Lyrm1 mRNA compared with NC cells. The size and ultrastructure of mitochondria in Lyrm1 knockdown adipocytes was similar to those of the NC cells. There was no significant difference in mtDNA copy number between the two groups. The total level of ATP production, mitochondrial membrane potential and Ucp2 mRNA expression levels were dramatically increased in adipocytes transfected with Lyrm1 RNAi. Furthermore, the level of ROS was dramatically decreased in Lyrm1 knockdown adipocytes. Knockdown of the Lyrm1 gene in adipocytes resulted in dramatically increased cellular ATP production, mitochondrial membrane potentials and levels Ucp2 mRNA, while ROS levels were significantly decreased. These results imply that mitochondrial function is improved in adipocytes after the knockdown of Lyrm1.

Knockdown of NYGGF4 increases glucose transport in C2C12 mice skeletal myocytes by activation IRS-1/PI3K/AKT insulin pathway.

NYGGF4, an obesity-related gene, is proposed to be involved in the development of insulin resistance. Skeletal muscle is a primary target organ for insulin and NYGGF4 showed a relatively high expression level in skeletal muscle. Therefore, this study aimed to explore the effect of NYGGF4 on insulin sensitivity of skeletal muscle cells. RNA interference (RNAi) was adopted to silence NYGGF4 expression in mice C2C12 skeletal myocytes. A remarkably increased insulin-stimulated glucose uptake and GLUT4 translocation was observed in NYGGF4 silencing C2C12 cells. Importantly, the enhanced glucose uptake induced by NYGGF4 silencing could be abrogated by the PI3K inhibitor LY294002. In addition, the crucial molecules involved in PI3K insulin signaling pathway were detected by western blotting. The results showed that NYGGF4 knockdown dramatically activate the insulin-stimulated phosphorylation of IRS-1 and AKT. Taken together, these data demonstrate that NYGGF4 knockdown increases glucose transport in myocytes by activation of the IRS-1/PI3K/AKT insulin pathway.

α-Lipoic acid ameliorates impaired glucose uptake in LYRM1 overexpressing 3T3-L1 adipocytes through the IRS-1/Akt signaling pathway.

Overexpression of the Homo sapiens LYR motif containing 1 (LYRM1) causes mitochondrial dysfunction and induces insulin resistance in 3T3-L1 adipocytes. α-Lipoic acid (α-LA), a dithiol compound with antioxidant properties, improves glucose transport and utilization in 3T3-L1 adipocytes. The aim of this study was to investigate the direct effects of α-LA on reactive oxygen species (ROS) production and insulin sensitivity in LYRM1 overexpressing 3T3-L1 adipocytes and to explore the underlying mechanism. Pretreatment with α-LA significantly increased both basal and insulin-stimulated glucose uptake and insulin-stimulated GLUT4 translocation, while intracellular ROS levels in LYRM1 overexpressing 3T3-L1 adipocytes were decreased. These changes were accompanied by a marked upregulation in expression of insulin-stimulated tyrosine phosphorylation of IRS-1 and serine phosphorylation of Akt following treatment with α-LA. These results indicated that α-LA protects 3T3-L1 adipocytes from LYRM1-induced insulin resistance partially via its capacity to restore mitochondrial function and/or increase phosphorylation of IRS-1 and Akt.

α-Lipoic acid protects 3T3-L1 adipocytes from NYGGF4 (PID1) overexpression-induced insulin resistance through increasing phosphorylation of IRS-1 and Akt.

NYGGF4 (also called PID1) was demonstrated that it may be related to the development of obesity-related IR. We aimed in the present study to further elucidate the effects of NYGGF4 on IR and the underlying mechanisms through using α-Lipoic acid (LA) treatment, which could facilitate glucose transport and utilization in fully differentiated adipocytes. Our data showed that the LA pretreatment strikingly enhanced insulin-stimulated glucose uptake through increasing GLUT4 translocation to the PM in NYGGF4 overexpression adipocytes. The reactive oxygen species (ROS) levels in NYGGF4 overexpression adipocytes were strikingly enhanced, which could be decreased by the LA pretreatment. NYGGF4 overexpression resulted in significant inhibition of tyrosine phosphorylation of IRS-1 and serine phosphorylation of Akt, whereas incubation with LA strongly activated IRS-1 and Akt phosphorylation in NYGGF4 overexpression adipocytes. These results suggest that LA protects 3T3-L1 adipocytes from NYGGF4-induced IR partially through increasing phosphorylation of IRS-1 and Akt and provide evidence that NYGGF4 may be a potential target for the treatment of obesity and obesity-related IR.

NYGGF4 (PID1) effects on insulin resistance are reversed by metformin in 3T3-L1 adipocytes.

NYGGF4 (also called PID1) is a recently discovered gene that is involved in obesity-related insulin resistance (IR). We aimed in the present study to further elucidate the effects of NYGGF4 on IR and the underlying mechanisms through using metformin treatment in 3T3-L1 adipocytes. Our data showed that the metformin pretreatment strikingly enhanced insulin-stimulated glucose uptake through increasing GLUT4 translocation to the PM in NYGGF4 overexpression adipocytes. NYGGF4 overexpression resulted in significant inhibition of tyrosine phosphorylation of IRS-1 and serine phosphorylation of Akt, whereas incubation with metformin strongly activated IRS-1 and Akt phosphorylation in NYGGF4 overexpression adipocytes. The reactive oxygen species (ROS) levels in NYGGF4 overexpression adipocytes were strikingly enhanced, which could be decreased by the metformin pretreatment. Our data also showed that metformin increased the expressions of PGC1-α, NRF-1, and TFAM, which were reduced in the NYGGF4 overexpression adipocytes. These results suggest that NYGGF4 plays a role in IR and its effects on IR could be reversed by metformin through activating IRS-1/PI3K/Akt and AMPK-PGC1-α pathways.

Molecular and biological characterization of interferon-γ-inducible-lysosomal thiol reductase gene in zebrafish (Danio rerio).

In mammals, interferon-γ-inducible-lysosomal thiol reductase (GILT) has been demonstrated to play a key role in the processing and presentation of MHC class II-restricted antigen (Ag) by catalyzing disulfide bond reduction, thus unfolding native protein Ag and facilitating subsequent cleavage by proteases. Here, we reported the cloning of a GILT gene homologue from zebrafish (zGILT), a tropical freshwater fish. The full-length cDNA of zGILT gene is 768 nucleotides (nt) encoding a protein of 255 amino acids (aa), with a putative molecular weight of 28.33 kDa. The deduced protein is highly homologous to that of fish and mammalian GILTs and shares 57.1% sequence identity to that of Atlantic salmon and 55.7-21.6% sequence identity to that of various mammals. The deduced protein possesses all the main features characteristic of known GILT proteins including the signature sequence CQHGX2ECX2NX4C spanning residues 117-132, CXXC motif at residues 72-75, one potential sites for N-linked glycosylation at residual positions 54. The zGILT expression is obviously up-regulated in spleen and kidney after immunization with LPS although it also is constitutively expressed in heart, liver, muscle and intestine, suggesting that zGILT may be involved in the immune response to bacterial challenge. The soluble recombinant protein was successfully purified using Ni-nitrilotriacetic acid resin. Recombinant His-zsGILT appeared on SDS-PAGE in the ranges of their estimated size of 18.94-kDa. After purification, further study revealed that zsGILT was capable of catalyzing the reduction of the interchain disulfide bonds intact IgG. These results will allow for further investigation to unravel the role of this key enzyme in class II MHC-restricted antigen processing and to use zebrafish as an in vivo model for related studies.

Effects of embryonic exposure to polychlorinated biphenyls on zebrafish (Danio rerio) retinal development.

Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that affect embryonic development. The purpose of this study was to examine the effects of embryonic exposure to PCBs on early retinal development in zebrafish, Danio rerio. Zebrafish embryos were immediately exposed to different concentrations (0, 0.125, 0.25, 0.5, 1.0 and 2.0 mg) of PCBs per liter of medium at 28.5 °C. Embryos were assessed at 30, 48, 72 and 96 h post-fertilization (hpf) for changes in embryonic survival rate, development, larval retinal morphology and ultrastructure of the retina. The results show that PCB exposure decreased the survival rate of embryos in a time- and dose-dependent manner. Embryos exposed to the higher concentrations of PCBs (0.5, 1.0 and 2.0 mg l(-1) ) displayed obvious gross morphological deformities. At 72 hpf, the retinal layer development of zebrafish was delayed at higher PCB concentrations (1.0 mg l(-1) ). At 96 hpf, irregularity of photoreceptor cells arrangement and thickening of photoreceptor and ganglionic layers were observed in PCB-treated larvae at concentrations of 0.25-1 mg l(-1) . Ultrastructural examination showed signs of growth inhibition of the photoreceptor outer segment at 0.25-1 mg l(-1) PCB exposure at 72 hpf, as well as the appearance of massive vacuoles and holes inside the outer segments in the PCB exposure group at 96 hpf. These results suggest that embryonic exposure to moderate and high levels of PCBs induced developmental deficits in zebrafish retinas, particularly in photoreceptor cells.

Long-term consequences of the early treatment of children with congenital hypothyroidism detected by neonatal screening in Nanjing, China: a 12-year follow-up study.

This study was performed to investigate the prevalence of congenital hypothyroidism (CH) in neonates in Nanjing, China and the long-term consequences of early treatment. A total of 442 454 neonates were screened for CH and 183 neonates were confirmed, with a prevalence of 1 in 2418. Of these, 163 neonates completed the follow-up process and 163 healthy children were recruited as the control group. The height, weight and body mass index (BMI) of the children with CH from 0.5 to 6 years were not significantly different from the control group (p > 0.05). The children with CH had a significantly increased risk for being overweight or obese between 0.5 and 6 years (p < 0.05). The children with CH showed a significantly lower developmental quotient (DQ) than the control group in all four areas of the Gesell test (p < 0.05). The results suggest that children with CH that has been identified by newborn screening and early treatment have normal growth and neuromotor development.

Genomic DNA methylation changes in NYGGF4-overexpression 3T3-L1 adipocytes.

NYGGF4, an obesity-related gene, is proposed to be involved in the development of insulin resistance; however, the underlying molecular mechanisms remain unclear. In the present analysis, NimbleGen tiling arrays were used to determine the patterns of genomic DNA methylation at CpG islands and promoters in NYGGF4-overexpression adipocytes. A total of 2352 CpG dinucleotides in 2018 genes and 3490 CpG dinucleotides in 3064 genes were found to be hypermethylated or hypomethylated, respectively, in NYGGF4-overexpression adipocytes. Furthermore, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis revealed enrichment of biological processes associated with energy metabolism and signal transduction events, including the peroxisome proliferator-activated receptor gamma (PPARγ) signaling pathway, and mitogen-activated protein kinases(MAPK) and Ras homolog gene family, member A (RhoA) signaling. These data demonstrate that differentially methylated genes are significantly overrepresented in NYGGF4-overexpression adipocytes, providing valuable clues for further exploration of the role of NYGGF4 in insulin sensitivity regulation.

[Detection of 9p partial trisomy using array-based comparative genomic hybridization].

OBJECTIVE: To detect chromosomal aberrations in a child with developmental delay and speech and language disorders in order to explore the underlying genetic causes of congenital malformation, and to investigate the feasibility of array-based comparative genomic hybridization (array-CGH) for molecular genetic diagnosis. METHODS: G-banding and array-CGH were applied to characterize the genetic abnormality in the three family members. RESULTS: G-banding analysis revealed the affected child and the healthy mother are both carriers of inv(9)(p13q13), while the child has carried a chromosome fragment derived from chromosome 13. Array-CGH analysis indicated the derivative chromosome fragment has originated from 9p with breakpoints at around 9p13.1-p24.3. CONCLUSION: Trisomy 9p13.1-p24.3 may be the cause of congenital malformation in the child. For its high resolution and high accuracy, array-CGH is a powerful tool for genetic analysis.

[A new component of breast milk: microRNA].

MicroRNA (miRNA) is a class of non-coding endogenous small molecule single strand RNA which is found in human body fluids. In recent years, miRNAs have been found in breast milk and parts of miRNAs are related to immune organ development and regulation of the immune function in infants. This article summarizes the functions of miRNA in breast milk and evidence-based clinical practice, and the differences between microRNA content and species in breast milk and cow milk. Understanding the role of miRNA can bring new opportunities for childhood nutrition research.