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Background: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a hepatic enzyme that regulates circulating low-density lipoprotein (LDL) cholesterol levels by binding to LDL receptors (LDLR) and promoting their degradation. Although PCSK9 inhibitors were shown to reduce the risk of cardiovascular disease, a warning was issued concerning their possible impact on cognitive functions. In Alzheimer’s disease (AD), it is believed that cognitive impairment is associated with cholesterol metabolism alterations, which could involve PCSK9. The main objective of this study is to determine if PCSK9 plays a significant role in the pre-symptomatic phase of the disease when the pathophysiological markers of AD unfolds and, later, when cognitive symptoms emerge. Methods and findings: To test if PCSK9 is associated with AD pathology, we measured its expression levels in 65 autopsy confirmed AD brains and 45 age and gender matched controls. Messenger ribonucleic acid (mRNA) were quantified using real-time polymerase chain reaction (RT-PCR) and protein levels were quantified using enzyme-linked immunosorbent assay (ELISA). PCSK9 was elevated in frontal cortices of AD subjects compared to controls, both at the mRNA and protein levels. LDLR protein levels were unchanged in AD frontal cortices, despite and upregulation at the mRNA level. To verify if PCSK9 dysregulation was observable before the onset of AD, we measured its expression in the cerebrospinal fluid (CSF) of 104 “at-risk” subjects and contrasted it with known apolipoproteins levels and specific AD biomarkers using ELISAs. Positive correlations were found between CSF PCSK9 and apolipoprotein E (APOE), apolipoprotein J (APOJ or CLU), apolipoprotein B (APOB), phospho Tau (pTau) and total Tau. To investigate if PCSK9 levels were driven by genetic variants, we conducted an expression quantitative trait loci (eQTL) study using bioinformatic tools and found two polymorphisms in strong association. Further investigation of these variants in two independent cohorts showed a female specific association with AD risk and with CSF Tau levels in cognitively impaired individuals. Conclusions: PCSK9 levels differ between control and AD brains and its protein levels correlate with those of other lipoproteins and AD biomarkers even before the onset of the disease. PCSK9 regulation seems to be under tight genetic control in females only, with specific variants that could predispose to increased AD risk. [ABSTRACT FROM AUTHOR]

Alternative splicing is a co-transcriptional mechanism that generates protein diversity by including or excluding exons in different combinations, thereby expanding the diversity of protein isoforms of a single gene. Abnormalities in this process can result in deleterious effects to human health, and several xenobiotics are known to interfere with splicing regulation through multiple mechanisms. These changes could lead to human diseases such as cancer, neurological disorders, autoimmune diseases, and developmental disorders. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant generated as a byproduct of various industrial activities. Exposure to this dioxin has been linked to a wide range of pathologies through the alteration of multiple cellular processes. However, the effects of TCDD exposure on alternative splicing have not yet been studied. Here, we investigated whether a single po. dose of 5 μg/kg or 500 μg/kg TCDD influence hepatic alternative splicing in adult male C57BL/6Kou mouse. We identified several genes whose alternative splicing of precursor messenger RNAs was modified following TCDD exposure. In particular, we demonstrated that alternative splicing of Cyp1a1, Ahrr, and Actn1 was significantly altered after TCDD treatment. These findings show that the exposure to TCDD has an impact on alternative-splicing, and suggest a new avenue for understanding TCDD-mediated toxicity and pathogenesis. [ABSTRACT FROM AUTHOR]

Protein kinase B (AKT) is a serine/threonine kinase that functions as an important downstream effector of phosphoinositide 3-kinase. We have recently shown that MK-2206 and triciribine, two highly selective AKT inhibitors increase the level of low density lipoprotein receptor (LDLR) mRNA which leads to increased amount of cell-surface LDLRs. However, whereas MK-2206 induces transcription of the LDLR gene, triciribine stabilizes LDLR mRNA, raising the possibility that the two inhibitors may actually affect other kinases than AKT. In this study, we aimed to ascertain the role of AKT in regulation of LDLR mRNA expression by examining the effect of five additional AKT inhibitors on LDLR mRNA levels. Here we show that in cultured HepG2 cells, AKT inhibitors ARQ-092, AKT inhibitor VIII, perifosine, AT7867 and CCT128930 increase LDLR mRNA levels by inducing the activity of LDLR promoter. CCT128930 also increased the stability of LDLR mRNA. To study the role of AKT isoforms on LDLR mRNA levels, we examined the effect of siRNA-mediated knockdown of AKT1 or AKT2 on LDLR promoter activity and LDLR mRNA stability. Whereas knockdown of either AKT1 or AKT2 led to upregulation of LDLR promoter activity, only knockdown of AKT2 had a stabilizing effect on LDLR mRNA. Taken together, these results provide strong evidence for involvement of AKT in regulation of LDLR mRNA expression, and point towards the AKT isoform specificity for upregulation of LDLR mRNA expression. [ABSTRACT FROM AUTHOR]

Juvenile rainbow trout develop social hierarchies when held in dyads, and the development of socially subordinate (SS) and social dominance (SD) phenotypes in this context has been linked to specific changes in the hepatic energy metabolism of all major macronutrients. Following our recently reported finding that transcript abundance of drosha, a key component of the microRNA (miRNA) biogenesis pathway, is increased in paired juvenile rainbow trout irrespective of social status compared to socially isolated (SI) controls, we here determined global changes of the hepatic miRNA pathway genes in detail at the transcript and protein level. Both socially SD and SS rainbow trout exhibited increased Ago2 protein abundance compared to SI rainbow trout, suggesting that hepatic miRNA function is increased in rainbow trout maintained in dyads. Given the well-described differences in hepatic intermediary metabolism between socially SD and SS rainbow trout, and the important role of miRNAs in the posttranscriptional regulation of metabolic pathways, we also identified changes in hepatic miRNA abundance between socially SS and SD rainbow trout using small RNA next generation sequencing. We identified a total of 24 differentially regulated miRNAs, with 15 miRNAs that exhibited increased expression, and 9 miRNAs that exhibited decreased expression in the liver of socially SS trout compared to socially SD trout. To identify potential miRNA-dependent posttranscriptional regulatory pathways important for social status-dependent regulation of hepatic metabolism in rainbow trout, we used an in silico miRNA target prediction and pathway enrichment approach. We identified enrichment for pathways related to metabolism of carbohydrates, lipids and proteins in addition to organelle-specific processes involved in energy metabolism, especially mitochondrial fusion and fission. Select predicted miRNA-mRNA target pairs within these categories were quantitatively analyzed by real-time RT-PCR to validate candidates for future studies that will probe the functional metabolic roles of specific hepatic miRNAs in the development of socially SD and SS metabolic phenotypes. [ABSTRACT FROM AUTHOR]

Background: The use of medicinal plants and their derivatives is increasing, and approximately one-third of all traditional herbal medicines are intended for wound treatment. Natural products used in these treatments include vegetable oils, which are rich in essential fatty acids. Once in contact with an ulcerative surface, the oil reaches the blood and lymphatic vessels, thus eliciting systemic effects. Objective: This study evaluated the local and possible systemic effects of essential fatty acids (sunflower oil) applied topically to rat wounds. Methods: Cutaneous punch wounds (6 mm) were produced on the dorsa of 30 rats. Saline (SS), mineral oil (MO) or essential fatty acid (EFA) solutions were applied topically. Healing was evaluated after 2, 4 and 10 days (n = 5 per group) by visual and histological/morphometric examination, second harmonic generation (SHG) microscopy, and cytokine and growth factor quantification in the scar tissue (real-time PCR) and in serum (ELISA). Results: MO/EFA-treated animals had higher IGF-1, leptin, IL-6 and IFN-γ mRNA expression and lower serum IL-6 levels than the control (SS/MO) animals. SHG analysis showed no difference in collagen density between the animals treated with MO and EFA. Conclusion: EFA treatment induces topical (observed by local IGF-1, leptin, IL-6 and IFN-γ production) and systemic effects, lowering IL-6 levels in the serum. As the oil is widely used to shorten ulcer healing time, studies are needed to evaluate the treatment safety and possible undesired effects. [ABSTRACT FROM AUTHOR]

During pond culture of Eriocheir sinensis, a high limb-impairment rate restricts the industry development and quality. Therefore, research on limb autotomy and regeneration has important practical significance for the industrial development and basic biology of E. sinensis. This study evaluated the changes in bud morphology, growth-related gene expression and nutritional status during cheliped regeneration in E. sinensis. The study found that the new cheliped was pre-formed in the bud and then regenerated with the completion of molting of E. sinensis. The new cheliped was similar in morphology to the normal cheliped after the first molting but smaller in size. The qRT-PCR results of growth-related genes showed that the expression levels of EcR-mRNA (ecdysteroid receptor) and Chi-mRNA (chitinase) were significantly up-regulated, whereas the expression of MIH-mRNA (molt-inhibiting hormone) was significantly down-regulated (P < 0.05). The nutritional status during the regeneration process showed that the hepatopancreas total lipid content decreased significantly within 28 days and was significantly lower in the autotomy group than in the control group at 14 d and 21 d (P < 0.05). The hepatopancreas fatty acid composition results showed that saturated fatty acids (SFA), highly unsaturated fatty acids (HUFA) and n-3/n-6 were significantly higher in the autotomy group than in the control group at 21 d (P < 0.05), whereas the ∑ n-6 PUFA and ∑ n-3 PUFA at 1 d and 7 d, and the monounsaturated fatty acid (MUFA) at 28 d in the autotomy group were significantly lower than in the control group (P < 0.05). Moreover, the levels of eicosatetraenoic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) showed that DHA was significantly lower at 7 d and significantly higher at 21 d in the autotomy group than in the control group (P < 0.05), whereas ARA and EPA were not significantly different between the two groups. Muscle L-tryptophan content was significantly lower at 1 d and significantly higher at 7 d in the autotomy group than in the control group (P < 0.05). These results indicate that during the cheliped regeneration process, crabs could accelerate molting and regeneration by regulating growth-related gene expression (e.g., EcR-mRNA and MIH-mRNA) and nutrient metabolism (e.g., lipid metabolism). [ABSTRACT FROM AUTHOR]

In this study, we examined the role of mRNAs and miRNAs in variations in intramuscular fat content in the longissimus dorsi muscle in Xinjiang brown cattle. Two groups of Xinjiang brown cattle with extremely different intramuscular fat content in the longissimus dorsi were selected for combined of miRNA and mRNA analysis using an RNA-Seq. In total, 296 mRNAs and 362 miRNAs were significantly differentially expressed, including 155 newly predicted miRNAs, 275 significantly upregulated genes, 252 significantly upregulated miRNAs, 21 significantly downregulated genes and 110 significantly downregulated miRNAs. The combined miRNA and mRNA analysis identified 96 differentially expressed miRNAs and 27 differentially expressed mRNAs. In all, 47 upregulated miRNAs had a regulatory effect on 14 differentially downregulated target genes, and 49 downregulated miRNAs had a regulatory effect on 13 upregulated target genes. To verify the sequencing results, 10 differentially expressed genes (DEGs) and 10 differentially expressed miRNAs were selected for qRT-PCR. The qRT-PCR results confirmed the sequencing results. The results of this study shed light on the molecular regulation of bovine adipose tissue, which might help with the development of new strategies for improving meat quality and animal productivity in beef cattle to provide healthier meat products for consumers. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify potential mRNA expression changes in chicken livers associated with environmental exposure to dichloro-diphenyl-trichloroethane (DDT) and its metabolites (DDTs). In particular, we focused on genes relating to the immune system and metabolism. We analyzed liver samples from free-ranging chickens in KwaZulu-Natal, South Africa, for contamination by DDTs. This area predominantly uses DDT in its malaria control program, and homes are sprayed annually with the pesticide. Genes relating to the immune system and metabolism were selected as potential genetic biomarkers that could be linked to higher contamination with DDTs. RT-qPCR analysis on 39 samples showed strong correlations between DDTs contamination and mRNA expression for the following genes: AvBD1, AvBD2, AvBD6 and AvBD7 (down-regulated), and CYP17, ELOVL2 and SQLE (up-regulated). This study shows for the first time interesting and significant correlations between genetic material collected from environmentally-exposed chickens and mRNA expression of several genes involved in immunity and metabolism. These findings show the usefulness of analysis on field samples from a region with high levels of environmental contamination in detecting potential biomarkers of exposure. In particular, we observed clear effects from DDT contamination on mRNA expression of genes involved in immune suppression, endocrine-disrupting effects, and lipid dysregulation. These results are of interest in guiding future studies to further elucidate the pathways involved in and clinical importance of toxicity associated with DDT exposure from contaminated environments, to ascertain the health risk to livestock and any subsequent risks to food security for people. [ABSTRACT FROM AUTHOR]

The activation of peroxisomeproliferator-activated receptor (PPAR) α can stimulate the expression of ceramide-related enzymes, and a major component of strawberry seed extract (SSE) tiliroside enhances the expression of PPARα. We determined whether SSE and tiliroside may stimulate ceramide synthesis in the stratum corneum (SC) of the human epidermal equivalents (HEEs) culture model. Treatment with SSE at 1.0 and 3.0 μg/mL elicited a significant increase in the total ceramide content in the SC, which was accompanied by a significant increase in almost all ceramide species except for ceramide [EOS] and [AP]. Treatment with tiliroside at 0.3 μg/mL slightly accentuated the total ceramide content in the SC together with a significant increase in the ceramide [NS, NDS] content. Messenger RNA analysis demonstrated that SSE at 1 or 3 μg/mL significantly stimulated the gene expression of serine palmitoyltransferase (SPT) 2, ceramide synthase (CerS) 3, glucosylceramide synthase (GCS), and β-glucocerebrosidase (GBA) but not of SPT1, sphingomyelin synthase (SMS) 1/2 and acid sphingomyelinase (ASM). In contrast, tiliroside elicited significant increases in the gene expression levels of GCS and GBA only at 0.3 and/or 0.1 μg/mL. Western blotting analysis revealed that both SSE and tiliroside enhanced the protein expression levels of GCS and GBA but not of SPT2 at 1 or 3 and 0.1 or 0.3 μg/mL, respectively. These findings suggested that both SSE and tiliroside have a distinct potential to stimulate the level of ceramide [NS, NDS] in the SC by enhancing the expression of GCS and GBA. The higher stimulatory effect with SSE than tiliroside on SC ceramide synthesis correlates with the significant increase observed with SSE but not tiliroside in the gene expression levels of SPT2 and CerS3. Therefore, it is anticipated that SSE is effective in improving skin barrier function and moisture retention in several ceramide-deficit skin conditions, including surfactant-induced roughened skin, xerosis, and atopic dermatitis. [ABSTRACT FROM AUTHOR]

Bisphenol-A (BPA) is a lipophilic compound widely used in the manufacture of plastic items and thought to play a role in the growing obesity epidemic. Recent publications suggest that BPA may have a pro-adipogenic effect. Here we explore the effect of low, but environmentally relevant, concentrations of BPA on adipogenesis using a variety of cellular models. Mouse 3T3-L1, C3H10T1/2 and human adipose-derived stromal cells (hADSCs) were cultured with BPA concentrations ranging from 0.1nM to 100μM. We failed to observe positive effects on differentiation at any dose or in any model. 3T3-L1 adipocytes differentiated with high concentrations of BPA showed decreased mRNA expression of several adipocyte markers. Mature adipocytes differentiated in the presence of BPA were insulin resistant, with an approximate 25% reduction in insulin-stimulated glucose uptake. This was accompanied by a significant decrease in insulin-stimulated Akt phosphorylation, and an increase in mRNA levels of inflammatory markers (i.e. IL-6, TNFα). In conclusion, low, but environmentally relevant, doses of BPA may contribute to the development of a chronic, low-grade inflammatory state in exposed adipocytes, which in turn may affect adipose tissue insulin sensitivity, independent of adipogenesis. These studies suggest an alternative mechanism by which BPA may contribute to the development of obesity. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the effects of altering the ratio of n-6 to n-3 fatty acids in the diet on meat quality, fatty acid composition of muscle, and expression of lipogenic genes in the muscle of Boer goats. A total of twenty-one Boer goats (5 months old; 31.66±1.07 kg body weight) were randomly assigned to three dietary treatments with n-6:n-3 fatty acid ratios of 2.27:1 (LR), 5.01:1 (MR) and 10.38:1 (HR), fed at 3.7% of body weight. After 100 days of feeding, all goats were slaughtered and the longissimus dorsi muscle was sampled for analysis of fatty acids and gene expression. The dietary treatments did not affect (P>0.05) the carcass traits, and meat quality of growing goats. The concentrations of cis-9,trans-11 conjugated linoleic acid, trans vaccenic acid, polyunsaturated fatty acids, and unsaturated/saturated fatty acid ratios linearly increased (P<0.01) with decreasing dietary n-6:n-3 fatty acid ratios, especially for LR in the longissimus dorsi muscle of goats. In contrast, the mRNA expression level of the PPARα and PPARγ was down-regulated and stearoyl-CoA desaturase up-regulated in the longissimus dorsi of growing goats with increasing dietary n-6:n-3 fatty acid ratios (P<0.01). In conclusion, the results obtained indicate that the optimal n-6:n-3 fatty acid ratio of 2.27:1 exerted beneficial effects on meat fatty acid profiles, leading towards an enrichment in n-3 polyunsaturated fatty acids and conjugated linoleic acid in goat intramuscular fat. [ABSTRACT FROM AUTHOR]

Background and aims: Nonalcoholic fatty liver disease is one of the major complications of obesity, occurring already in pediatric age. Insulin like growth factor-I has been proposed as a potential therapeutic agent for its beneficial effect in experimental liver fibrosis. The aim of this work was to investigate the expression of insulin-like growth factor-I and its receptor in the liver of children with biopsy-proven nonalcoholic fatty liver disease and relate it to liver histological features. Methods: 45 obese children and adolescents (14 females and 31 males) with nonalcoholic fatty liver disease were included. Insulin like growth factor-I and its receptor expression was evaluated in liver tissue by immunofluorescence and qPCR. Results: The expression of insulin like growth factor-I and its receptor were significantly related to fibrosis and were higher in children with stage 3 fibrosis compared to stage 1 and 2 (p<0.001 and p = 0.007 respectively). mRNA of insulin like growth factor-I receptor was higher in more advanced stages of fibrosis (p<0.001). Furthermore, the expression of insulin like growth factor-I and its receptor in hepatic stellate cells, the cell type mostly involved in fibrosis progression, was significantly increased in stage 3 fibrosis compared to stage 1 (p = 0.01 and p = 0.008 respectively). Conclusions: We demonstrated for the first time that insulin like growth factor-I and its receptor are upregulated in children with nonalcoholic fatty liver disease. These findings give a new hint for the potential therapeutic use of insulin like growth factor-I in pediatric nonalcoholic fatty liver disease complicated by liver fibrosis. [ABSTRACT FROM AUTHOR]

High-glycemic-index diets, as well as a sedentary lifestyle are considered as determinant factors for the development of obesity, type 2 diabetes, and cardiovascular diseases in humans. These diets have been shown to shorten the life span of C. elegans in a manner that is dependent on insulin signaling, but the participation of other signaling pathways have not been addressed. In this study, we have determined that worms fed with high-glucose diets show alterations in glucose content and uptake, triglyceride content, body size, number of eggs laid, egg-laying defects, and signs of oxidative stress and accelerated aging. Additionally, we analyzed the participation of different key regulators of carbohydrate and lipid metabolism, oxidative stress and longevity such as SKN-1/NRF2, HIF-1/HIF1α, SBP-1/SREBP, CRH-1/CREB, CEP-1/p53, and DAF-16/FOXO, in the reduction of lifespan in glucose-fed worms. [ABSTRACT FROM AUTHOR]

The cure rate for late stage epithelial ovarian cancer (EOC) has not significantly improved over several decades. New and more effective targets and treatment modalities are urgently needed. RNA-seq analyses of a syngeneic EOC cell pair, representing more and less aggressive tumor cells in vivo were conducted. Bioinformatics analyses of the RNA-seq data and biological signaling and function studies have identified new targets, such as ZIP4 in EOC. Many up-regulated tumor promoting signaling pathways have been identified which are mainly grouped into three cellular activities: 1) cell proliferation and apoptosis resistance; 2) cell skeleton and adhesion changes; and 3) carbohydrate metabolic reprograming. Unexpectedly, lipid metabolism has been the major down-regulated signaling pathway in the more aggressive EOC cells. In addition, we found that hypoxic responsive genes were at the center stage of regulation and detected functional changes were related to cancer stem cell-like activities. Moreover, our genetic, cellular, biochemical, and lipidomic analyses indicated that cells grown in 2D vs. 3D, or attached vs. suspended had dramatic changes. The important clinical implications of peritoneal cavity floating tumor cells are supported by the data proved in this work. Overall, the RNA-seq data provide a landscape of gene expression alterations during tumor progression. [ABSTRACT FROM AUTHOR]

Despite the capacity to accumulate ~70% w/w of lipids, commercially produced unicellular green alga A. protothecoides may become compromised due to the high cost of phosphate fertilizers. To address this limitation A. protothecoides was selected for adaptation to conditions of 100× and 5× lower phosphate and peptone, respectively, compared to ‘wild-type media’. The A. protothecoides showed initial signs of adaptation by 45–50 days, and steady state growth at ~100 days. The low phosphate (P)-adapted strain produced up to ~30% greater biomass, while total lipids (~10% w/w) remained about the same, compared to the wild-type strain. Metabolomic analyses indicated that the low P-adapted produced 3.3-fold more saturated palmitic acid (16:0) and 2.2-fold less linolenic acid (18:3), compared to the wild-type strain, resulting in an ~11% increase in caloric value, from 19.5kJ/g for the wild-type strain to 21.6kJ/g for the low P-adapted strain, due to the amounts and composition of certain saturated fatty acids, compared to the wild type strain. Biochemical changes in A. protothecoides adapted to lower phosphate conditions were assessed by comparative RNA-Seq analysis, which yielded 27,279 transcripts. Among them, 2,667 and 15 genes were significantly down- and up-regulated, at >999-fold and >3-fold (adjusted p-value <0.1), respectively. The expression of genes encoding proteins involved in cellular processes such as division, growth, and membrane biosynthesis, showed a trend toward down-regulation. At the genomic level, synonymous SNPs and Indels were observed primarily in coding regions, with the 40S ribosomal subunit gene harboring substantial SNPs. Overall, the adapted strain out-performed the wild-type strain by prioritizing the use of its limited phosphate supply for essential biological processes. The low P-adapted A. protothecoides is expected to be more economical to grow over the wild-type strain, based on overall greater productivity and caloric content, while importantly, also requiring 100-fold less phosphate. [ABSTRACT FROM AUTHOR]

Glucose and palmitate synergistically stimulate insulin secretion, but chronically elevated they induce apoptotic β-cell death. The glucotoxic effect has been attributed, at least partly, to the upregulation of the oxidative stress marker thioredoxin interacting protein (TXNIP). Palmitate downregulates TXNIP expression, the functional significance of which is still under debate. This study examines the mechanism and consequence of palmitate-mediated TXNIP regulation in insulin secreting cells. Palmitate (600 μM) reduced TXNIP mRNA levels in isolated human and mouse islets independently of FFAR1/GPR40. Similar effects of palmitate were observed in INS-1E cells and mimicked by other long chain fatty acids. The lowering of TXNIP mRNA was significant already 1 h after addition of palmitate, persisted for 24 h and was directly translated to changes in TXNIP protein. The pharmacological inhibition of palmitate-induced phosphorylation of AMPK, ERK1/2, JNK and PKCα/β by BML-275, PD98059, SP600125 and Gö6976, respectively, did not abolish palmitate-mediated TXNIP downregulation. The effect of palmitate was superimposed by a time-dependent (8 h and 24 h) decline of TXNIP mRNA and protein. This decline correlated with accumulation of secreted insulin into the medium. Accordingly, exogenously added insulin reduced TXNIP mRNA and protein levels, an effect counteracted by the insulin/IGF-1 receptor antagonist linsitinib. The inhibition of PI3K and Akt/PKB increased TXNIP mRNA levels. The histone deacetylase (HDAC1/2/3) inhibitor MS-275 completely abrogated the time-dependent, insulin-mediated reduction of TXNIP, leaving the effect of palmitate unaltered. Acute stimulation of insulin secretion and chronic accentuation of cell death by palmitate occurred independently of TXNIP regulation. On the contrary, palmitate antagonized glucose-augmented ROS production. In conclusion, glucose-induced TXNIP expression is efficiently antagonized by two independent mechanisms, namely via an autocrine activation of insulin/IGF-1 receptors involving HDAC and by palmitate attenuating oxidative stress of β-cells. [ABSTRACT FROM AUTHOR]

A group of 240-day-old Ross cockerels were used in a 4-week experiment to assess the effect of the fat type on the intestinal digestibility of fatty acids (FAs), the FA profiles of breast meat and abdominal fat, and the mRNA expression of six hepatic lipid-related genes. Experimental diets were supplemented with rapeseed oil, pork lard or palm oil at 60 g/kg. In the control diet, wheat starch was substituted for the fat source. The highest ileal digestibility of the fat and all FAs (except stearic acid) was observed in chickens fed lard. The content of fat in the breast meat of chickens was not significantly influenced by the fat supplements. The FA profiles of breast meat and abdominal fat reflected the FA composition of the diet. In the meat of chickens fed rapeseed oil, oleic acid was the predominant FA. Palmitic acid was the most abundant FA in the meat of chickens fed lard or palm oil. Oleic acid was the most abundant FA in the abdominal fat of all chickens. The highest mRNA expression of desaturases (Δ5-, Δ6- and Δ9-) was observed in chickens fed palm oil. The mRNA expression of hepatic FA synthase was higher in chickens fed palm oil or lard than in chickens fed rapeseed oil. The expression of HMG-CoA reductase was higher in chickens fed palm oil than in those fed rapeseed oil or lard. It can be concluded that rapeseed oil and lard are better sources of lipids than palm oil. These former two sources contain more digestible fatty acids and provide a lower concentration of SFAs in the meat and fat of chickens. [ABSTRACT FROM AUTHOR]

Background: Reproductive hens are subjected to a restricted diet to limit the decline in fertility associated with change in body mass. However, endocrine and tissue responses to diet restriction need to be documented. Objective: We evaluated the effect of different levels of feed restriction, with or without fish oil supplementation, on metabolic parameters and adipokine levels in plasma and metabolic tissues of reproductive hens. Methods: We designed an in vivo protocol involving 4 groups of hens; RNS: restricted (Rt) unsupplemented, ANS: ad libitum (Ad, receiving an amount of feed 1.7 times greater than animals on the restricted diet) unsupplemented, RS: Rt supplemented, and AS: Ad supplemented. The fish oil supplement was used at 1% of the total diet composition. Results: Hens fed with the Rt diet had a significantly (P < 0.0001) lower growth than Ad hens, while the fish oil supplementation had no effect on these parameters. Furthermore, the bioelectrical impedance analysis (BIA) and the fat ultrasonographic examinations produced similar results to the other methods that required animals to be killed (carcass analysis and weight of adipose tissue). In addition, the Rt diet significantly (P < 0.05) decreased plasma levels of triglycerides, phospholipids, glucose and ADIPOQ, and fish oil supplementation decreased plasma levels of RARRES2. We also showed a positive correlation between insulin values and ADIPOQ or NAMPT or RARRES2 values, and a negative correlation of fat percentage to RARRES2 values. Moreover, the effects of the Rt diet and fish oil supplementation on the mRNA expression depended on the factors tested and the hen age. Conclusions: Rt diet and fish oil supplementation are able to modulate metabolic parameters and the expression of adipokines and their receptors in metabolic tissue. [ABSTRACT FROM AUTHOR]

Background: High mortality rate of critically-ill patients could be induced by sepsis and septic shock, which is the extremely life threatening. The purpose of this work is to identify and evaluate the potential regulatory mechanism of LPS-induced inflammation associated with miR-6835 and lipid rafts in HUVECs. Methods: The 3’ UTR luciferase activity of AdipoR1 was detected, which was predicted the potential target gene of miR-6835. Moreover, the treated HUVECs with or without inhibitors or mimics of miR-6835 were used. Furthermore, the bio-functions of HUVECs were explored. The protein expression levels of SIRT-1, AMPK, and AdipoR1 were assessed, which were involved in the AdipoR1 signaling pathway. Then, the interaction between TLR-4 and AdipoR1 in lipid rafts and its mediation role on LPS-induced inflammation was investigated in HUVECs. Results: MiR-6835 targeted directly on AdipoR1, and suppressed its expression in mRNA (mimics of miR-6835: 0.731±0.016 vs control: 1.527±0.015, P<0.001) and proteins levels, then regulated protein expression of SIRT-1 and AMPK, which were the downstream target genes of AdipoR1 signaling pathway. MiR-6835 enhanced LPS-induced inflammation process in HUVECs (TNF-α: LPS+mimics of miR-6835: 1638.51±78.43 vs LPS: 918.73±39.73, P<0.001; IL-6: LPS+mimics of miR-6835: 1249.35±69.51 vs LPS: 687.52±43.64, P<0.001), which was associated with the interaction between TLR-4 and AdipoR1 in lipid rafts. Conclusions: MiR-6835 is the key regulator of LPS-induced inflammation process in HUVECs. The interaction between TLR-4 and AdipoR1 mediated by lipid rafts at membrane of HUVECs with inflammation process induced by miR-6835. Our results demonstrated a hopeful strategy for treatment on sepsis by aiming at lipid rafts and miR-6835. [ABSTRACT FROM AUTHOR]

Since its initial application in mammalian cells, CRISPR-Cas9 has rapidly become a preferred method for genome engineering experiments. The Cas9 nuclease is targeted to genomic DNA using guide RNAs (gRNA), either as the native dual RNA system consisting of a DNA-targeting CRISPR RNA (crRNA) and a trans-activating crRNA (tracrRNA), or as a chimeric single guide RNA (sgRNA). Entirely DNA-free CRISPR-Cas9 systems using either Cas9 protein or Cas9 mRNA and chemically synthesized gRNAs allow for transient expression of CRISPR-Cas9 components, thereby reducing the potential for off-targeting, which is a significant advantage in therapeutic applications. In addition, the use of synthetic gRNA allows for the incorporation of chemical modifications for enhanced properties including improved stability. Previous studies have demonstrated the utility of chemically modified gRNAs, but have focused on one pattern with multiple modifications in co-electroporation with Cas9 mRNA or multiple modifications and patterns with Cas9 plasmid lipid co-transfections. Here we present gene editing results using a series of chemically modified synthetic sgRNA molecules and chemically modified crRNA:tracrRNA molecules in both electroporation and lipid transfection assessing indel formation and/or phenotypic gene knockout. We show that while modifications are required for co-electroporation with Cas9 mRNA, some modification patterns of the gRNA are toxic to cells compared to the unmodified gRNA and most modification patterns do not significantly improve gene editing efficiency. We also present modification patterns of the gRNA that can modestly improve Cas9 gene editing efficiency when co-transfected with Cas9 mRNA or Cas9 protein (> 1.5-fold difference). These results indicate that for certain applications, including those relevant to primary cells, the incorporation of some, but not all chemical modification patterns on synthetic crRNA:tracrRNA or sgRNA can be beneficial to CRISPR-Cas9 gene editing. [ABSTRACT FROM AUTHOR]

During avian embryonic development, endodermal epithelial cells (EECs) absorb yolk through the yolk sac membrane. Sterol O-acyltransferase (SOAT) is important for esterification and yolk lipid utilization during development. Because the major enzyme for yolk sac membrane cholesteryl ester synthesis is SOAT1, we cloned the avian SOAT1 promoter and elucidated the cellular functions of SOAT1. Treatments with either glucagon, isobutylmethylxanthine (IBMX), an adenylate cyclase activator (forskolin), a cAMP analog (dibutyryl-cAMP), or a low glucose concentration all increased SOAT1 mRNA accumulation in EECs from Japanese quail, suggesting that SOAT1 is regulated by nutrients and hormones through a cAMP-dependent pathway. Activity of protein kinase A (PKA) was increased by IBMX, whereas co-treatment with the PKA inhibitor, H89 negated the increase in PKA activity. Cyclic AMP-induced EECs had greater cholesterol esterification than untreated EECs. By promoter deletion and point-mutation, the cAMP-response element (-349 to -341 bp) was identified as critical in mediating transcription of SOAT1. In conclusion, expression of SOAT1 was regulated by a cAMP-dependent pathway and factors that increase PKA will increase SOAT1 to improve the utilization of lipids in the EECs and potentially modify embryonic growth. [ABSTRACT FROM AUTHOR]

Intramuscular fat (IMF) is known to enhance beef palatability and can be markedly increased by castration. However, there is little understanding of the molecular mechanism underlying the IMF deposition after castration of beef cattle. We hypothesize that genetic regulators function differently in IMF from bulls and steers. Therefore, after detecting serum testosterone and lipid parameter, as well as the contents of IMF at 6, 12, 18 and 24 months, we have investigated differentially expressed (DE) microRNAs (miRNAs) and mRNAs in IMF of bulls and steers at 24 months of age in Qinchuan cattle using next-generation sequencing, and then explored the possible biopathways regulating IMF deposition. Serum testosterone levels were significantly decreased in steers, whereas IMF content, serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TGs) were markedly increased in steers. Comparing the results of steers and bulls, 580 upregulated genes and 1,120 downregulated genes in IMF tissues were identified as DE genes correlated with IMF deposition. The upregulated genes were mainly associated with lipid metabolism, lipogenesis and fatty acid transportation signalling pathways, and the downregulated genes were correlated with immune response and intracellular signal transduction. Concurrently, the DE miRNAs—important players in adipose tissue accumulation induced by castration—were also examined in IMF tissues; 52 DE miRNAs were identified. The expression profiles of selected genes and miRNAs were also confirmed by quantitative real-time PCR (qRT-PCR) assays. Using integrated analysis, we constructed the microRNA-target regulatory network which was supported by target validation using the dual luciferase reporter system. Moreover, Ingenuity Pathway Analysis (IPA) software was used to construct a molecular interaction network that could be involved in regulating IMF after castration. The detected molecular network is closely associated with lipid metabolism and adipocyte differentiation, which is supported by functional identification results of bta-let-7i on bovine preadipocytes. These results provided valuable insights into the molecular mechanisms of the IMF phenotype differences between steers and bulls. [ABSTRACT FROM AUTHOR]

Background: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in Western countries. Both iron and lipid metabolism seem to be involved in its pathogenesis. We aimed to assess the relationship between levels of hepcidin, the master iron-regulatory protein, in plasma and the presence of NAFLD in morbidly obese (MO) patients, and to investigate the association between the hepatic expression of the main iron and lipid metabolism -related genes. Materials and methods: Enzyme-linked immunosorbent assay was used to measure plasma hepcidin levels in 49 normal-weight control women, 23 MO women with normal liver (NL) histology and 46 MO women with NAFLD. The mRNA expression of hepcidin, the main iron metabolism-related genes, and the main lipid-metabolism genes was quantified by qRT-PCR in liver biopsies from members of the MO group undergoing bariatric surgery. Results: Circulating hepcidin levels were significantly greater in MO than in normal-weight control women. However, there were no significant differences between MO women with NL and those with NAFLD. PCR analysis showed increased expression of hepcidin, FPN1, TfR1 and TfR2 in the liver of MO NAFLD women compared to those with NL. Moreover, a positive association of hepatic hepcidin mRNA expression and the iron metabolism-related genes was found with some key genes involved in the lipid metabolism. Conclusion: These findings suggest that circulating hepcidin levels are associated with obesity but not with the presence of NAFLD. However, the hepatic expression of hepcidin and the iron metabolism-related genes seem to play a role in regulating lipid metabolism pathways in liver, which has implications for NAFLD pathogenesis. [ABSTRACT FROM AUTHOR]

Intrauterine growth restriction (IUGR) induced by placental restriction (PR) in the sheep negatively impacts lung and pulmonary surfactant development during fetal life. Using a sheep model of low birth weight (LBW), we found that there was an increase in mRNA expression of surfactant protein (SP)-A, -B and -C in the lung of LBW lambs but no difference in the protein expression of SP-A or -B. LBW also resulted in increased lysosome-associated membrane glycoprotein (LAMP)-3 mRNA expression, which may indicate an increase in either the density of type II Alveolar epithelial cells (AEC) or maturity of type II AECs. Although there was an increase in glucocorticoid receptor (GR) and 11β-hydroxysteroid dehydrogenase (11βHSD)-1 mRNA expression in the lung of LBW lambs, we found no change in the protein expression of these factors, suggesting that the increase in SP mRNA expression is not mediated by increased GC signalling in the lung. The increase in SP mRNA expression may, in part, be mediated by persistent alterations in hypoxia signalling as there was an increase in lung HIF-2α mRNA expression in the LBW lamb. The changes in the hypoxia signalling pathway that persist within the lung after birth may be involved in maintaining SP production in the LBW lamb. [ABSTRACT FROM AUTHOR]

Non-alcoholic steatohepatitis (NASH) is a liver disease with the potential to lead to cirrhosis and hepatocellular carcinoma. Interleukin-6 (IL-6) has been implicated in the pathogenesis of NASH, with the so-called IL-6 ‘trans-signaling’ cascade being responsible for the pro-inflammatory actions of this cytokine. We aimed to block IL-6 ‘trans-signaling’, using a transgenic mouse that overexpresses human soluble glycoprotein130 (sgp130Fc Tg mice) fed a commonly used dietary model of inducing NASH (methionine and choline deficient-diet; MCD diet) and hypothesized that markers of NASH would be ameliorated in such mice. Sgp130Fc Tg and littermate control mice were fed a MCD or control diet for 4 weeks. The MCD diet induced many hallmarks of NASH including hepatomegaly, steatosis, and liver inflammation. However, in contrast with other mouse models and, indeed, human NASH, the MCD diet model did not increase the mRNA or protein expression of IL-6. Not surprisingly, therefore, markers of MCD diet-induced NASH were unaffected by sgp130Fc transgenic expression. While the MCD diet model induces many pathophysiological markers of NASH, it does not induce increased IL-6 expression in the liver, a key hallmark of human NASH. We, therefore, caution the use of the MCD diet as a viable mouse model of NASH. [ABSTRACT FROM AUTHOR]

Nucleobindin-1 has high sequence similarity to nucleobindin-2, which encodes the anorectic and metabolic peptide, nesfatin-1. We previously reported a nesfatin-1-like peptide (NLP), anorectic in fish and insulinotropic in mice islet beta-like cells. The main objective of this research was to determine whether NLP is a metabolic regulator in male Wistar rats. A single intraperitoneal (IP) injection of NLP (100 μg/kg BW) decreased food intake and increased ambulatory movement, without causing any change in total activity or energy expenditure when compared to saline-treated rats. Continuous subcutaneous infusion of NLP (100 μg/kg BW) using osmotic mini-pumps for 7 days caused a reduction in food intake on days 3 and 4. Similarly, water intake was also reduced for two days (days 3 and 4) with the effect being observed during the dark phase. This was accompanied by an increased RER and energy expenditure. However, decreased whole-body fat oxidation, and total activity were observed during the long-term treatment (7 days). Body weight gain was not significantly different between control and NLP infused rats. The expression of mRNAs encoding adiponectin, resistin, ghrelin, cholecystokinin and uncoupling protein 1 (UCP1) were significantly upregulated, while leptin and peptide YY mRNA expression was downregulated in NLP-treated rats. These findings indicate that administration of NLP at 100 μg/kg BW reduces food intake and modulates whole body energy balance. In summary, NLP is a novel metabolic peptide in rats. [ABSTRACT FROM AUTHOR]

Firemaster® 550 (FM550) is a chemical mixture currently used as an additive flame retardant in commercial products, and is comprised of 2-ethylhexyl-2,3,4,5-tertrabromobenzoate (TBB), bis(2-ethylhexyl) tetrabromophthalate (TBPH), triphenyl phosphate (TPP), and isopropylated triphenyl phosphate (IPTP). Animal and in vitro studies suggest that FM550, TPP and IPTP may have adipogenic effects and may exert these effects through PPARγ activation. Using murine 3T3-L1 preadipocytes, we investigated the detailed expression of transcription factors and adipogenic markers in response to FM550 and its components. Further we investigated the mechanism of action of the peroxisome proliferator-activated receptor gamma (PPARγ) on downstream targets of the receptor by focussing on the mature adipocyte marker, adipocyte protein 2 (aP2). In addition, we set to elucidate the components responsible for the adipogenic effects seen in the FM550 mixture. We show that FM550 and its components TPP, IPTP, and TBPH, but not TBB induced lipid accumulation in a dose-dependent manner. Interestingly, despite displaying enhanced lipid accumulation, TBPH did not alter the mRNA or protein expression of terminal differentiation markers. In contrast, FM550, TPP, and IPTP treatment enhanced lipid accumulation, and mRNA and protein expression of terminal differentiation markers. To further delineate the mechanisms of action of FM550 and its components we focussed on aP2 promoter activity. For this purpose we used the enhancer region of the mouse aP2 promoter using a 584-bp reporter construct containing an active PPRE located 5.4 kb away from the transcription start site of aP2. Exposure to FM550, IPTP, and TPP significantly increased PPARγ mediated aP2 enhancer activity. Furthermore, we show that TPP- and IPTP-dependent upregulation of aP2 was significantly inhibited by the selective PPARγ antagonist GW9662. In addition, chromatin immunoprecipitation experiments showed that IPTP and TPP treatment led to the recruitment of PPARγ to the regulatory region of aP2. [ABSTRACT FROM AUTHOR]

In mammalian preimplantation development, pluripotent cells are set aside from cells that contribute to extra-embryonic tissues. Although the pluripotent cell population of mouse and human embryos can be cultured as embryonic stem cells, little is known about the pathways involved in formation of a bovine pluripotent cell population, nor how to maintain these cells in vitro. The objective of this study was to determine the transcriptomic profile related to bovine pluripotency. Therefore, in vitro derived embryos were cultured in various culture media that recently have been reported capable of maintaining the naïve pluripotent state of human embryonic cells. Gene expression profiles of embryos cultured in these media were compared using microarray analysis and quantitative RT-PCR. Compared to standard culture conditions, embryo culture in ‘naïve’ media reduced mRNA expression levels of the key pluripotency markers NANOG and POU5F1. A relatively high percentage of genes with differential expression levels were located on the X-chromosome. In addition, reduced XIST expression was detected in embryos cultured in naïve media and female embryos contained fewer cells with H3K27me3 foci, indicating a delay in X-chromosome inactivation. Whole embryos cultured in one of the media, 5iLA, could be maintained until 23 days post fertilization. Together these data indicate that ‘naïve’ conditions do not lead to altered expression of known genes involved in pluripotency. Interestingly, X-chromosome inactivation and development of bovine embryos were dependent on the culture conditions. [ABSTRACT FROM AUTHOR]

The significance of maternal cholesterol transporting to the fetus under normal as well as pathological circumstances is less understood. The objective of this study was to observe the effects of maternal hypercholesterolemia on placental cholesterol transportation. Human full-time placenta, maternal and venous cord blood were sampled at delivery from the pregnant women with serum total cholesterol (TC) concentrations at third trimester higher than 7.25 mM (n = 19) and the pregnant women with normal TC concentrations (n = 19). Serum lipids and expression of genes related to cholesterol transportation were measured by western blot or real-time PCR. The results indicated that serum TC, high density lipoprotein cholesterol (HDL-C), and low density lipoprotein cholesterol (LDL-C) levels were significantly increased, in pregnancies, but decreased in cord blood in hypercholesterolemic group compared to the matched control group. All the subjects were no-drinking, non-smoker, and gestational disease free. The mRNA expression of lipoprotein receptors, including LDLR and VLDLR were significantly increased, while the protein expression of PCSK9 was significantly increased in hypercholesterolemic placenta. In conclusion, maternal hypercholesterolemia might decrease the transportation of cholesterol from mother to fetus because of the high levels of PCSK9 protein expression. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) regulate metabolic tissue development and function, including adipogenesis. However, little is known about the function and profile of lncRNAs in intramuscular preadipocyte differentiation in chicken. Here, we identified lncRNAs in chicken intramuscular preadipocytes at different differentiation stages using RNA sequencing. A total of 1,311,382,604 clean reads and 25,435 lncRNAs were obtained from 12 samples. In total, 7,433 differentially expressed genes (4,698 lncRNAs and 2,735 mRNAs) were identified by pairwise comparison. These 7,433 differentially expressed genes were grouped into 11 clusters based on their expression patterns by K-means clustering. Using Weighted Gene Coexpression Network Analysis, we identified four stage-specific modules positively related to I0, I2, I4, and I6 stages and two stage-specific modules negatively related to I0 and I2 stages, respectively. Many well-known and novel pathways associated with intramuscular preadipocyte differentiation were identified. We also identified hub genes in each stage-specific module and visualized them in Cytoscape. Our analysis revealed many highly-connected genes, including XLOC_058593, BMP3, MYOD1, and LAMP3. This study provides a valuable resource for chicken lncRNA study and improves our understanding of the biology of preadipocyte differentiation in chicken. [ABSTRACT FROM AUTHOR]

Previous study found that rifampicin caused intrahepatic cholestasis. This study investigated the effects of rifampicin on hepatic lipid metabolism. Mice were orally administered with rifampicin (200 mg/kg) daily for different periods. Results showed that serum TG level was progressively reduced after a short elevation. By contrast, hepatic TG content was markedly increased in rifampicin-treated mice. An obvious hepatic lipid accumulation, as determined by Oil Red O staining, was observed in mice treated with rifampicin for more than one week. Moreover, mRNA levels of Fas, Acc and Scd-1, several key genes for fatty acid synthesis, were elevated in rifampicin-treated mice. In addition, the class B scavenger receptor CD36 was progressively up-regulated by rifampicin. Interestingly, hepatic SREBP-1c and LXR-α, two important transcription factors that regulate genes for hepatic fatty acid synthesis, were not activated by rifampicin. Instead, hepatic PXR was rapidly activated in rifampicin-treated mice. Hepatic PPARγ, a downstream target of PXR, was transcriptionally up-regulated. Taken together, the increased hepatic lipid synthesis and uptake of fatty acids from circulation into liver jointly contribute to rifampicin-induced hepatic lipid accumulation. The increased uptake of fatty acids from circulation into liver might be partially attributed to rifampicin-induced up-regulation of PPARγ and its target genes. [ABSTRACT FROM AUTHOR]

Recent studies have linked gestational exposure to highly caloric diets with a disrupted endogenous cannabinoid system (ECS). In the present study, we have extended these studies by analyzing the impact of the exposure to a palatable diet during gestation and lactation on a) the adult expression of endocannabinoid-related behaviors, b) the metabolic profile of adult offspring and c) the mRNA expression of the signaling machinery of the ECS in the hypothalamus, the liver and the adipose tissue of adult offspring of both sexes. Exposure to a palatable diet resulted in a) sex-dimorphic and perinatal diet specific feeding behaviors, including the differential response to the inhibitory effects of the cannabinoid receptor inverse agonist AM251, b) features of metabolic syndrome including increased adiposity, hyperleptinemia, hypertriglyceridemia and hypercholesterolemia and c) tissue and sex-specific changes in the expression of both CB1 and CB2 receptors and in that of the endocannabinoid-degrading enzymes FAAH and MAGL, being the adipose tissue the most affected organ analyzed. Since the effects were observed in adult animals that were weaned while consuming a normal diet, the present results indicate that the ECS is one of the targets of maternal programming of the offspring energy expenditure. These results clearly indicate that the maternal diet has long-term effects on the development of pups through multiple alterations of signaling homeostatic pathways that include the ECS. The potential relevance of these alterations for the current obesity epidemic is discussed. [ABSTRACT FROM AUTHOR]

Tanshinone IIA, one of the most pharmacologically bioactive phytochemicals isolated from Salvia miltiorrhiza Bunge, possesses several biological activities such as anti-inflammation, anti-cancer, neuroprotection and hypolipidemic activities. In this study, we aim to investigate the hypocholesterolemic effect of tanshinone IIA in hepatic cells. We demonstrated that tanshinone IIA significantly increased the amount of low-density lipoprotein receptor (LDLR) and LDL uptake activity in HepG2 cells at the post-transcriptional regulation. We further demonstrated that tanshinone IIA inhibited the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and mature protein, which may lead to an increase the cell-surface LDLR in hepatic cells. We further identified a regulatory DNA element involved in the tanshinone IIA-mediated PCSK9 down-regulation, which is located between the -411 and -336 positions of the PCSK9 promoter. Moreover, we found that tanshinone IIA markedly increased the nuclear forkhead box O3a (FoxO3a) level, enhanced FoxO3a/PCSK9 promoter complexes formation and decreased the PCSK9 promoter binding capacity of hepatocyte nuclear factor 1α (HNF-1α), resulting in suppression of PCSK9 gene expression. Finally, we found that the statin-induced PCSK9 overexpression was attenuated and the LDLR activity was elevated in a synergic manner by combination of tanshinone IIA treatment in HepG2 cells. Overall, our results reveal that the tanshinone IIA modulates LDLR level and activity via down-regulation of PCSK9 expression in hepatic cells. Our current findings provide a molecular basis of tanshinone IIA to develop PCSK9 inhibitors for cholesterol management. [ABSTRACT FROM AUTHOR]

ELOVL family member 6, elongation of very long chain fatty acids (Elovl6) is a microsomal enzyme, which regulates the elongation of C12-16 saturated and monounsaturated fatty acids. Elovl6 has been shown to be associated with various pathophysiologies including insulin resistance, atherosclerosis, and non-alcoholic steatohepatitis. To investigate a potential role of Elovl6 during bone development, we here examined a skeletal phenotype of Elovl6 knockout (Elovl6-/-) mice. The Elovl6-/- skeleton was smaller than that of controls, but exhibited no obvious patterning defects. Histological analysis revealed a reduced length of proliferating and an elongated length of hypertrophic chondrocyte layer, and decreased trabecular bone in Elovl6-/- mice compared with controls. These results were presumably due to a modest decrease in chondrocyte proliferation and accelerated differentiation of cells of the chondrocyte lineage. Consistent with the increased length of the hypertrophic chondrocyte layer in Elovl6-/- mice, Collagen10α1 was identified as one of the most affected genes by ablation of Elovl6 in chondrocytes. Furthermore, this elevated expression of Collagen10α1 of Elovl6-null chondrocytes was likely associated with increased levels of Foxa2/a3 and Mef2c mRNA expression. Relative increases in protein levels of nuclear Foxa2 and cytoplasmic histone deacethylase 4/5/7 were also observed in Elovl6 knockdown cells of the chondrocyte lineage. Collectively, our data suggest that Elovl6 plays a critical role for proper development of embryonic growth plate. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of three weeks of rosuvastatin (Ros) treatment alone and in combination with voluntary training (Tr) on expression of genes involved in cholesterol metabolism (LDLR, PCSK9, LRP-1, SREBP-2, IDOL, ACAT-2 and HMGCR) in the liver of eight week-old ovariectomized (Ovx) rats. Sprague Dawley rats were Ovx or sham-operated (Sham) and kept sedentary for 8 weeks under a standard diet. Thereafter, rats were transferred for three weeks in running wheel cages for Tr or kept sedentary (Sed) with or without Ros treatment (5mg/kg/day). Six groups were formed: Sham-Sed treated with saline (Sal) or Ros (Sham-Sed-Sal; Sham-Sed-Ros), Ovx-Sed treated with Sal or Ros (Ovx-Sed-Sal; Ovx-Sed-Ros), Ovx trained treated with Sal or Ros (Ovx-Tr-Sal; Ovx-Tr-Ros). Ovx-Sed-Sal rats depicted higher (P < 0.05) body weight, plasma total cholesterol (TC) and LDL-C, and liver TC content compared to Sham-Sed-Sal rats. In contrast, mRNA levels of liver PCSK9, LDLR, LRP-1 as well as plasma PCSK9 concentrations and protein levels of LRP-1 were reduced (P < 0.01) in Ovx-Sed-Sal compared to Sham-Sed-Sal rats. However, protein levels of LDLR increased (P < 0.05) in Ovx-Sed-Sal compared to Sham-Sed-Sal rats. Treatment of Ovx rats with Ros increased (P < 0.05) mRNA and protein levels of LRP-1 and PCSK9 but not mRNA levels of LDLR, while its protein abundance was reduced at the level of Sham rats. As a result, plasma LDL-C was not reduced. Exercise alone did not affect the expression of any of these markers in Ovx rats. Overall, Ros treatment corrected Ovx-induced decrease in gene expression of markers of cholesterol metabolism in liver of Ovx rats, but without reducing plasma LDL-C concentrations. Increased plasma PCSK9 levels could be responsible for the reduction of liver LDLR protein abundance and the absence of reduction of plasma LDL-C after Ros treatment. [ABSTRACT FROM AUTHOR]

Lactobacillus acidophilus species are well-known probiotics with the beneficial activity of regulating cholesterol levels. In this study, we showed that L. acidophilus K301 reduced the level of cholesterol through reverse transport in macrophages. L. acidophilus K301 upregulated the mRNA and protein levels of genes such as ATP-binding cassette A1 (ABCA1) and ATP-binding cassette G1 (ABCG1) under the control of liver X receptor (LXR), resulting in increased apoA-I-dependent cholesterol efflux in phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 cells. L. acidophilus K301 induced both ABCA1 and ABCG1 through the endogenous LXR agonist 24(S), 25-epoxcycholesterol, which is synthesized by intracellular cholesterol synthetic pathways. In vivo studies using L. acidophilus K301-treated ApoE-/- mice showed reduced accumulation of lipoproteins in the arterial lumen. The inhibitory effects of L. acidophilus K301 on accumulation of lipoprotein in atherosclerotic plaques were mediated by the induction of squalene reductase (SQLE) and oxidosqualene cyclase (OSC) and resulted in ABCA1-mediated cholesterol efflux. Taken together, our findings revealed that Lactobacillus acidophilus K301 regulates the expression of genes related to cholesterol reverse transport via the induction of endogenous LXR agonist, suggesting the therapeutic potential of Lactobacillus acidophilus K301 as an anti-atherosclerotic agent. [ABSTRACT FROM AUTHOR]

Background: Artemisia sphaerocephala, a semi-shrub belonging to the Artemisia genus of the Compositae family, is an important pioneer plant that inhabits moving and semi-stable sand dunes in the deserts and steppes of northwest and north-central China. It is very resilient in extreme environments. Additionally, its seeds have excellent nutritional value, and the abundant lipids and polysaccharides in the seeds make this plant a potential valuable source of bio-energy. However, partly due to the scarcity of genetic information, the genetic mechanisms controlling the traits and environmental adaptation capacity of A. sphaerocephala are unknown. Results: Here, we present the first in-depth transcriptomic analysis of A. sphaerocephala. To maximize the representation of conditional transcripts, mRNA was obtained from 17 samples, including living tissues of desert-growing A. sphaerocephala, seeds germinated in the laboratory, and calli subjected to no stress (control) and high and low temperature, high and low osmotic, and salt stresses. De novo transcriptome assembly performed using an Illumina HiSeq 2500 platform resulted in the generation of 68,373 unigenes. We analyzed the key genes involved in the unsaturated fatty acid synthesis pathway and identified 26 A. sphaerocephala fad2 genes, which is the largest fad2 gene family reported to date. Furthermore, a set of genes responsible for resistance to extreme temperatures, salt, drought and a combination of stresses was identified. Conclusion: The present work provides abundant genomic information for functional dissection of the important traits of A. sphaerocephala and contributes to the current understanding of molecular adaptive mechanisms of A. sphaerocephala in the desert environment. Identification of the key genes in the unsaturated fatty acid synthesis pathway could increase understanding of the biological regulatory mechanisms of fatty acid composition traits in plants and facilitate genetic manipulation of the fatty acid composition of oil crops. [ABSTRACT FROM AUTHOR]

Spaceflight affects numerous organ systems in the body, leading to metabolic dysfunction that may have long-term consequences. Microgravity-induced alterations in liver metabolism, particularly with respect to lipids, remain largely unexplored. Here we utilize a novel systems biology approach, combining metabolomics and transcriptomics with advanced Raman microscopy, to investigate altered hepatic lipid metabolism in mice following short duration spaceflight. Mice flown aboard Space Transportation System -135, the last Shuttle mission, lose weight but redistribute lipids, particularly to the liver. Intriguingly, spaceflight mice lose retinol from lipid droplets. Both mRNA and metabolite changes suggest the retinol loss is linked to activation of PPARα-mediated pathways and potentially to hepatic stellate cell activation, both of which may be coincident with increased bile acids and early signs of liver injury. Although the 13-day flight duration is too short for frank fibrosis to develop, the retinol loss plus changes in markers of extracellular matrix remodeling raise the concern that longer duration exposure to the space environment may result in progressive liver damage, increasing the risk for nonalcoholic fatty liver disease. [ABSTRACT FROM AUTHOR]

Oocyte polarity and embryonic patterning are well-established features of development in lower species. Whether a similar form of pre-patterning exists in mammals is currently under hot debate in mice. This study investigated this issue for the first time in ovine as a large mammal model. Microsurgical trisection of unfertilized MII-oocytes revealed that cortical cytoplasm around spindle (S) contained significant amounts of total maternal mRNAs and proteins compared to matched cytoplast hemispheres that were located either near (NS) or far (FS) -to-spindle. RT-qPCR provided striking examples of maternal mRNA localized to subcellular substructures S (NPM2, GMNN, H19, PCAF, DNMT3A, DNMT1, and STELLA), NS (SOX2, NANOG, POU5F1, and TET1), and FS (GCN) of MII oocyte. Immunoblotting revealed that specific maternal proteins DNMT3A and NANOG were asymmetrically enriched in MII-spindle-half of the oocytes. Topological analysis of sperm entry point (SEP) revealed that sperm preferentially entered via the MII-spindle-half of the oocytes. Even though, the topological position of first cleavage plane with regard to SEP was quite stochastic. Spatial comparison of lipid content revealed symmetrical distribution of lipids between 2-cell blastomeres. Lineage tracing using Dil, a fluorescent dye, revealed that while the progeny of leading blastomere of 2-cell embryos contributed to more cells in the developed blastocysts compared to lagging counterpart, the contributions of leading and lagging blastomeres to the embryonic-abembryonic parts of the developed blastocysts were almost unbiased. And finally, separated sister blastomeres of 2-cell embryos had an overall similar probability to arrest at any stage before the blastocyst (2-cell, 4-cell, 8-cell, and morula) or to achieve the blastocyst stage. It was concluded that the localization of maternal mRNAs and proteins at the spindle are evolutionarily conserved between mammals unfertilized ovine oocyte could be considered polar with respect to the spatial regionalization of maternal transcripts and proteins. Even though, the principal forces of this definitive oocyte polarity may not persist during embryonic cleavages. [ABSTRACT FROM AUTHOR]

Background: Armolipid Plus (AP) is a nutraceutical that contains policosanol, fermented rice with red yeast, berberine, coenzyme Q10, folic acid, and astaxanthin. It has been shown to be effective in reducing plasma LDL cholesterol (LDLc) levels. In the multicenter randomized trial NCT01562080, there was large interindividual variability in the plasma LDLc response to AP supplementation. We hypothesized that the variability in LDLc response to AP supplementation may be linked to LDLR and PCSK9 polymorphisms. Material and Methods: We sequenced the LDLR 3′ and 5′ untranslated regions (UTR) and the PCSK9 5′ UTR of 102 participants with moderate hypercholesterolemia in trial NCT01562080. In this trial, 50 individuals were treated with AP supplementation and the rest with placebo. Results: Multiple linear regression analysis, using the response of LDLc levels to AP as the dependent variable, revealed that polymorphisms rs2149041 (c.-3383C>G) in the PCSK9 5′ UTR and rs14158 (c.*52G>A) in the LDLR 3′ UTR explained 14.1% and 6.4%, respectively, of the variability after adjusting for gender, age, and BMI of individuals. Combining polymorphisms rs2149041 and rs14158 explained 20.5% of this variability (p < 0.004). Conclusions: Three polymorphisms in the 3′ UTR region of LDLR, c.*52G>A, c.*504G>A, and c.*773A>G, and two at the 5′ UTR region of PCSK9, c.−3383C>G and c.−2063A>G, were associated with response to AP. These results could explain the variability observed in the response to berberine among people with moderate hypercholesterolemia, and they may be useful in identifying patients who could potentially benefit from supplementation with AP. [ABSTRACT FROM AUTHOR]

Visceral fat accretion is a hallmark of aging and is associated with aging-induced metabolic dysfunction. PPARγ agonist was reported to improve insulin sensitivity by redistributing fat from visceral fat to subcutaneous fat. The purpose of this study was to investigate the underlying mechanisms by which aging affects adipose tissue remodeling in a type 2 diabetic animal model and through which PPARγ activation modulates aging-related fat tissue distribution. At the ages of 21, 31 and 43 weeks, OLETF rats as an animal model of type 2 diabetes were evaluated for aging-related effects on adipose tissue metabolism in subcutaneous and visceral fat depots. During aging, the ratio of visceral fat weight to subcutaneous fat weight (V/S ratio) increased. Aging significantly increased the mRNA expression of genes involved in lipogenesis such as lipoprotein lipase, fatty acid binding protein aP2, lipin 1, and diacylglycerol acyltransferase 1, which were more prominent in visceral fat than subcutaneous fat. The mRNA expression of adipose triglyceride lipase, which is involved in basal lipolysis and fatty acid recycling, was also increased, more in visceral fat compared to subcutaneous fat during aging. The mRNA levels of the genes associated with lipid oxidation were increased, whereas the mRNA levels of genes associated with energy expenditure showed no significant change during aging. PPARγ agonist treatment in OLETF rats resulted in fat redistribution with a decreasing V/S ratio and improved glucose intolerance. The genes involved in lipogenesis decreased in visceral fat of the PPARγ agonist-treated rats. During aging, fat distribution was changed by stimulating lipid uptake and esterification in visceral fat rather than subcutaneous fat, and by altering the lipid oxidation. [ABSTRACT FROM AUTHOR]

Long-term-selected DUhTP mice represent a non-inbred model for inborn physical high-performance without previous training. Abundance of hepatic mRNA in 70-day male DUhTP and control mice was analyzed using the Affymetrix mouse array 430A 2.0. Differential expression analysis with PLIER corrected data was performed using AltAnalyze. Searching for over-representation in biochemical pathways revealed cholesterol metabolism being most prominently affected in DUhTP compared to unselected control mice. Furthermore, pathway analysis by AltAnalyze plus PathVisio indicated significant induction of glycolysis, fatty acid synthesis and cholesterol biosynthesis in the liver of DUhTP mice versus unselected control mice. In contrast, gluconeogenesis was partially inactivated as judged from the analysis of hepatic mRNA transcript abundance in DUhTP mice. Analysis of mRNA transcripts related to steroid hormone metabolism inferred elevated synthesis of progesterone and reduced levels of sex steroids. Abundance of steroid delta isomerase-5 mRNA (Hsd3b5, FC 4.97) was increased and steroid 17-alpha-monooxygenase mRNA (Cyp17a1, FC -11.6) was massively diminished in the liver of DUhTP mice. Assessment of steroid profiles by LC-MS revealed increased levels of progesterone and decreased levels of sex steroids in serum from DUhTP mice versus controls. Analysis of hepatic mRNA transcript abundance indicates that sterol regulatory element-binding protein-1 (SREBP-1) may play a major role in metabolic pathway activation in the marathon mouse model DUhTP. Thus, results from bioinformatics modeling of hepatic mRNA transcript abundance correlated with direct steroid analysis by mass spectrometry and further indicated functions of SREBP-1 and steroid hormones for endurance performance in DUhTP mice. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) B irradiation decreases blood adiponectin levels, but the mechanism is not well understood. This study investigated how UVB irradiation reduces adiponectin expression in ovarial adipose tissues. Female Hos:HR-1 hairless mice were exposed to UVB (1.6 J/cm2) irradiation and were killed 24 h later. UVB irradiation decreased the adiponectin protein level in the serum and the adiponectin mRNA level in ovarial adipose tissues. UVB irradiation also decreased the mRNA levels of peroxisome proliferator-activated receptor (PPAR) γ, CCAAT/enhancer binding protein (C/EBP) α, C/EBPβ, and fatty acid binding protein 4 (aP2) in ovarial adipose tissues. In contrast, UVB irradiation increased the mRNA levels of interleukin (IL)-6 and monocyte chemoattractant protein (MCP)-1 in ovarial adipose tissues. In the serum and liver, the levels of serum amyloid A (SAA), involved in PPARγ, C/EBPα, C/EBPβ, aP2, IL-6, and MCP-1 regulation, increased after UVB irradiation. The SAA gene is regulated by IL-1β, IL-6, and tumor necrosis factor-α, but only IL-6 expression increased in the liver after UVB irradiation. Additionally, in the liver, hypothalamus, and epidermis, UVB irradiation increased the expression of calcitonin gene-related peptide (CGRP), which upregulates SAA in the liver. Collectively, our results suggest that the CGRP signal induced by skin exposure to UVB transfers to the liver, possibly through the brain, and increases SAA production via IL-6 in the liver. In turn, serum SAA acts in an endocrine manner to decreases the serum adiponectin level by downregulating factors that regulate adiponectin expression in adipose tissues. [ABSTRACT FROM AUTHOR]

Previous studies have shown that whole body deletion of the glucagon receptor suppresses the ability of starvation to increase hepatic fibroblast growth factor 21 (FGF21) expression and plasma FGF21 concentration. Here, we investigate the mechanism by which glucagon receptor activation increases hepatic FGF21 production. Incubating primary rat hepatocyte cultures with glucagon, dibutyryl cAMP or forskolin stimulated a 3-4-fold increase in FGF21 secretion. The effect of these agents on FGF21 secretion was not associated with an increase in FGF21 mRNA abundance. Glucagon induction of FGF21 secretion was additive with the stimulatory effect of a PPARα activator (GW7647) on FGF21 secretion. Inhibition of protein kinase A (PKA) and downstream components of the PKA pathway [i.e. AMP-activated protein kinase and p38 MAPK] suppressed glucagon activation of FGF21 secretion. Incubating hepatocytes with an exchange protein directly activated by cAMP (EPAC)-selective cAMP analog [i.e. 8-(4-chlorophenylthio)-2'-O-methyladenosine-3', 5'-cyclic monophosphate (cpTOME)], stimulated a 3.9-fold increase FGF21 secretion, whereas inhibition of the EPAC effector, Rap1, suppressed glucagon activation of FGF21 secretion. Treatment of hepatocytes with insulin also increased FGF21 secretion. In contrast to glucagon, insulin activation of FGF21 secretion was associated with an increase in FGF21 mRNA abundance. Glucagon synergistically interacted with insulin to stimulate a further increase in FGF21 secretion and FGF21 mRNA abundance. These results demonstrate that glucagon increases hepatic FGF21 secretion via a posttranscriptional mechanism and provide evidence that both the PKA branch and EPAC branch of the cAMP pathway play a role in mediating this effect. These results also identify a novel synergistic interaction between glucagon and insulin in the regulation of FGF21 secretion and FGF21 mRNA abundance. We propose that this insulin/glucagon synergism plays a role in mediating the elevation in FGF21 production during starvation and conditions related to metabolic syndrome. [ABSTRACT FROM AUTHOR]

Lipid droplet-associated proteins such as perilipin 3 (PLIN3) and coatomer GTPase proteins (GBF1, ARF1, Sec23a, and ARFRP1) are expressed in skeletal muscle but little is known so far as to their regulation of lipolysis. We aimed here to explore the effects of lipolytic stimulation in vitro in primary human myotubes as well as in vivo following an acute exercise bout. In vitro lipolytic stimulation by epinephrine (100 μM) or by a lipolytic cocktail (30 μM palmitate, 4 μM forskolin, and 0.5 μM ionomycin, PFI) resulted in increases in PLIN3 protein content. Coatomer GTPases such as GBF1, ARF1, Sec23a, and ARFRP1 also increased in response to lipolytic stimuli. Furthermore, a long duration endurance exercise bout (20 males; age 24.0±4.5 y; BMI 23.6±1.8 kg/m2) increased PLIN3 protein in human skeletal muscle (p = 0.03) in proportion to ex vivo palmitate oxidation (r = 0.45, p = 0.04) and whole body in vivo fat oxidation (r = 0.52, p = 0.03). Protein content of ARF1 was increased (p = 0.04) while mRNA expression was increased for several other coatomers (GBF1, ARF1, and Sec23a, all p<0.05). These data provide novel observational insight into the possible relationships between lipolysis and PLIN3 along with these coatomoer GTPase proteins in human skeletal muscle. [ABSTRACT FROM AUTHOR]

Non-alcoholic fatty liver disease (NAFLD) is closely associated with obesity and insulin resistance. To better understand the pathophysiology of obesity-associated NAFLD, the present study examined the involvement of liver and adipose tissues in metformin actions on reducing hepatic steatosis and inflammation during obesity. C57BL/6J mice were fed a high-fat diet (HFD) for 12 weeks to induce obesity-associated NAFLD and treated with metformin (150 mg/kg/d) orally for the last four weeks of HFD feeding. Compared with HFD-fed control mice, metformin-treated mice showed improvement in both glucose tolerance and insulin sensitivity. Also, metformin treatment caused a significant decrease in liver weight, but not adiposity. As indicated by histological changes, metformin treatment decreased hepatic steatosis, but not the size of adipocytes. In addition, metformin treatment caused an increase in the phosphorylation of liver AMP-activated protein kinase (AMPK), which was accompanied by an increase in the phosphorylation of liver acetyl-CoA carboxylase and decreases in the phosphorylation of liver c-Jun N-terminal kinase 1 (JNK1) and in the mRNA levels of lipogenic enzymes and proinflammatory cytokines. However, metformin treatment did not significantly alter adipose tissue AMPK phosphorylation and inflammatory responses. In cultured hepatocytes, metformin treatment increased AMPK phosphorylation and decreased fat deposition and inflammatory responses. Additionally, in bone marrow-derived macrophages, metformin treatment partially blunted the effects of lipopolysaccharide on inducing the phosphorylation of JNK1 and nuclear factor kappa B (NF-κB) p65 and on increasing the mRNA levels of proinflammatory cytokines. Taken together, these results suggest that metformin protects against obesity-associated NAFLD largely through direct effects on decreasing hepatocyte fat deposition and on inhibiting inflammatory responses in both hepatocytes and macrophages. [ABSTRACT FROM AUTHOR]

To investigate the cholesterol-lowering effects of alfalfa saponin extract (ASE) and its regulation mechanism on some key genes involved in cholesterol metabolism, 40 healthy 7 weeks old male Sprague Dawley (SD) rats were randomly divided into four groups with 10 rats in each group: control group, hyperlipidemic group, ASE treatment group, ASE prevention group. The body weight gain, relative liver weight and serum lipid 1evels of rats were determined. Total cholesterol (TC) and total bile acids (TBA) levels in liver and feces were also measured. Furthermore, the activity and mRNA expressions of Hmgcr, Acat2, Cyp7a1 and Ldlr were investigated. The results showed the following: (1) The abnormal serum lipid levels in hyperlipidemic rats were ameliorated by ASE administration (both ASE prevention group and treatment group) (P<0.05). (2) Both ASE administration to hyperlipidemic rats significantly reduced liver TC and increased liver TBA level (P<0.05). TC and TBA levels in feces of hyperlipidemic rats were remarkably elevated by both ASE administration (P<0.05). (3) mRNA expressions of Hmgcr and Acat2 in the liver of hyperlipidemic rats were remarkably down-regulated (P<0.05), as well as mRNA expressions of Cyp7a1 and Ldlr were dramatically up-regulated by both ASE administration (P<0.05). The activities of these enzymes also paralleled the observed changes in mRNA levels. (4) There was no significant difference between ASE treatment and ASE prevention group for most parameters evaluated. Our present study indicated that ASE had cholesterol-lowering effects. The possible mechanism could be attributed to (1) the down-regulation of Hmgcr and Acat2, as well as up-regulation of Cyp7a1 and Ldlr in the liver of hyperlipidemic rats, which was involved in cholesterol biosynthesis, uptake, and efflux pathway; (2) the increase in excretion of cholesterol. The findings in our study suggested ASE had great potential usefulness as a natural agent for treating hyperlipidemia. [ABSTRACT FROM AUTHOR]

This study aimed to determine if 50 days of canola oil intake in the absence or presence of salt loading affects: (1) antioxidant and oxidative stress markers, (2) aortic mRNA of NADPH oxidase (NOX) subunits and superoxide dismutase (SOD) isoforms and (3) endothelial function in SHRSP rats. SHRSP rats were fed a diet containing 10 wt/wt% soybean oil or 10 wt/wt% canola oil, and given tap water or water containing 1% NaCl for 50 days. Without salt, canola oil significantly increased RBC SOD, plasma cholesterol and triglycerides, aortic p22phox, NOX2 and CuZn-SOD mRNA, and decreased RBC glutathione peroxidase activity. With salt, canola oil reduced RBC SOD and catalase activity, LDL-C, and p22phox mRNA compared with canola oil alone, whereas plasma malondialdehyde (MDA) was reduced and RBC MDA and LDL-C were higher. With salt, the canola oil group had significantly reduced endothelium-dependent vasodilating responses to ACh and contractile responses to norepinephrine compared with the canola oil group without salt and to the WKY rats. These results indicate that ingestion of canola oil increases O2− generation, and that canola oil ingestion in combination with salt leads to endothelial dysfunction in the SHRSP model. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes produce at least one structurally unique class of small helix-rich retinol- and fatty-acid-binding proteins that have no counterparts in their plant hosts. Herein we describe a protein of the plant-parasitic root-knot nematode Meloidogyne javanica, which is a member of the nematode-specific fatty-acid- and retinol-binding (Mj-FAR-1) family of proteins. The mj-far-1 mRNA was detected through M. javanica pre-parasitic J2s, migratory and sedentary parasitic stages by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Immunolocalization assays demonstrate that the FAR protein of Meloidogyne is secreted during sedentary stages, as evidenced by the accumulation of FAR at the nematode cuticle surface and along the adjacent host root tissues. Tomato roots constitutively expressing mj-far-1 demonstrated an increased susceptibility to root-knot nematodes infection as observed by accelerated gall induction and expansion, accompanied by a higher percentage of nematodes developing into mature females compared to control roots. RNA interference assays that expressed double-stranded RNA complementary to mj-far-1 in transgenic tomato lines specifically reduced nematode infection levels. Histological analysis of nematode-infested roots indicated that in roots overexpressing mj-far-1, galls contained larger feeding cells and might support a faster nematode development and maturation. Roots overexpressing mj-far-1 suppressed jasmonic acid responsive genes such as the proteinase inhibitor (Pin2) and γ-thionin, illustrating the possible role of Mj-FAR-1 in manipulating the lipid based signaling in planta. This data, suggests that Meloidogyne FAR might have a strategic function during the interaction of the nematode with its plant host. Our study present the first demonstration of an in planta functional characterization and localization of FAR proteins secreted by plant-parasitic nematodes. It provides evidence that Mj-FAR-1 facilitates infection most likely via the manipulation of host lipid-based defenses, as critical components for a successful parasitism by plant-parasitic nematodes. [ABSTRACT FROM AUTHOR]

Transcription factors LXRs, PPARs, and SREBPs have been implicated in a multitude of physiological and pathological processes including atherogenesis. However, little is known about the regulation of these transcription factors at different stages of atherosclerosis progression. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to compare the contents of mRNAs in pairs intact-injured aorta fragments taken from the same donors. Only minor changes in LXRα, LXRβ, PPARα, PPARγ, SREBP1, and SREBP2 mRNA levels were found in initial lesions as compared with intact non-diseased tissue. The contents of all mRNAs but SREBP2 mRNA were found to be progressively up-regulated in fatty streaks and fibrous lipoid plaques. These changes were only partially reproduced in cultured macrophages upon lipid loading. Wave-shaped changes in abundance of correlations between given group of mRNAs and 28 atherosclerosis-related mRNA species in the course of atherogenesis were observed. The impact of specific mRNA correlations on the total correlations also significantly varied between different lesion types. The study suggests that the extent and forms of LXR/PPAR/SREBP participation in intima functions vary nonlinear in individual fashion in atherogenesis. We speculate that the observed changes in mRNAs expression and coupling reflect shifts in lipid ligands availability and cellular composition in the course of atherosclerosis progression. [ABSTRACT FROM AUTHOR]