Molecular cloning and tissue expression of chicken AdipoR1 and AdipoR2 complementary deoxyribonucleic acids

AdipoR1 and AdipoR2 belong to a novel class of transmembrane receptors that mediate the effects of adiponectin. We have cloned the chicken AdipoR1 and AdipoR2 complementary deoxyribonucleic acids (cDNA) and determined their expression in various tissues. We also investigated the effect of feed deprivation on the expression of AdipoR1 or AdipoR2 mRNA in the chicken diencephalon, liver, anterior pituitary gland, and adipose tissue. The chicken AdipoR1 and AdipoR2 cDNA sequences were 76-83% identical to the respective mammalian sequences. A hydrophobicity analysis of the deduced amino acid sequences of chicken AdipoR1/AdipoR2 revealed seven distinct hydrophobic regions representing seven transmembrane domains. By RT-PCR, we detected AdipoR1 and AdipoR2 mRNA in adipose tissue, liver, anterior pituitary gland, diencephalon, skeletal muscle, kidney, spleen, ovary, and blood. AdipoR1 or AdipoR2 mRNA expression in various tissues was quantified by real-time quantitative PCR, and AdipoR1 mRNA expression was the highest in skeletal muscle, adipose tissue and diencephalon, followed by kidney, ovary, liver, anterior pituitary gland, and spleen. AdipoR2 mRNA expression was the highest in adipose tissue followed by skeletal muscle, liver, ovary, diencephalon, anterior pituitary gland, kidney, and spleen. We also found that a 48 h feed deprivation significantly decreased AdipoR1 mRNA quantity in the chicken pituitary gland, while AdipoR2 mRNA quantity was significantly increased in adipose tissue (P<0.05). We conclude that the AdipoR1 and AdipoR2 genes are ubiquitously expressed in chicken tissues and that their expression is altered by feed deprivation in the anterior pituitary gland and adipose tissue.     

Gene expression and hormonal regulation of adiponectin and its receptors in bovine mammary gland and mammary epithelial cells

Although the functions of adiponectin, a differentiated adipocyte‐derived hormone, in regulating glucose and fatty acid metabolism are regulated by two subtypes of adiponectin receptors (AdipoRs; AdipoR1 and AdipoR2), those in ruminants remain unclear. Therefore we examined the messenger RNA (mRNA) expression levels of adiponectin and its receptors in various bovine tissues and mammary glands among different lactation stages, and the effects of lactogenic hormones (insulin, dexamethasone and prolactin) and growth hormone (GH) on mRNA expression of the AdipoRs in cultured bovine mammary epithelial cells (BMEC). AdipoRs mRNAs were widely expressed in various bovine tissues, but adiponectin mRNA expression was significantly higher in adipose tissue than in other tissues. In the mammary gland, although adiponectin mRNA expression was significantly decreased at lactation, AdipoR1 mRNA expression was significantly higher at peak lactation than at the dry‐off stage. In BMEC, lactogenic hormones and GH upregulated AdipoR2 mRNA expression but did not change that of AdipoR1. In conclusion, adiponectin and its receptor mRNA were expressed in various bovine tissues and the adiponectin mRNA level was decreased during lactation. These results suggest that adiponectin and its receptors ware changed in mammary glands by lactation and that AdipoRs mRNA expression was regulated by different pathways in BMEC.     

冷应激条件下猪脂肪组织中脂联素及其受体 mRNA水平的表达变化

为了研究冷应激对脂肪代谢的影响,本试验分别在-15~-10 ℃、-10~-5 ℃、-5~0 ℃、15~18 ℃温度条件下采取猪颈部、背部皮下和内脏系膜脂肪组织,通过荧光定量RT-PCR方法检测脂联素及其受体mRNA的表达水平。结果显示,随着冷应激强度的逐渐加大,在颈部、背部皮下、内脏系膜Adiponectin mRNA的表达量逐渐降低,差异显著(P＜0.05);内脏系膜中AdipoR 1和AdipoR 2 mRNA表达量先逐渐升高后恢复正常,且差异极显著(P＜0.01);背部皮下AdipoR 2 mRNA表达量先逐渐降低后恢复正常,差异极显著(P＜0.01),AdipoR 1 mRNA表达量没有明显变化;颈部皮下AdipoR 2 mRNA的表达量先逐渐升高后恢复正常,差异极显著(P＜0.01),AdipoR 1 mRNA的表达量先升高后恢复正常,而后又升高,差异极显著(P＜0.01)。结果表明,脂联素及其受体参与冷应激过程,它们可能与冷应激条件下脂肪组织的重新分布有重要的关系。     

Tissue-specific downregulation of the adiponectin “system”: possible implications for fat accumulation tendency in the pig

Adiponectin's beneficial effects are mediated by the AdipoR1 and AdipoR2 receptors (AdipoRs). The pig is a good model to study complex disorders such as obesity. We analyzed the expression of adiponectin, AdipoRs and some key molecules of energy metabolism (AMP-activated protein kinase α [AMPKα], p38 mitogen-activated protein kinase [p38 MAPK], and PPARα) in 2 pig breeds that displayed an opposite genetic behavior for energy metabolism: Casertana (CE), a fat-type animal, and Large White (LW), a lean-type animal. Muscle, liver, visceral and subcutaneous adipose tissues, and brain tissues were examined. The AdipoRs cDNA sequences were identical in the 2 breeds. AdipoRs mRNA expression, measured in all tissues, was significantly lower only in the 2 adipose tissues of CE pigs (P < 0.05). The muscle expression of AdipoRs, AMPKα, p38 MAPK, and PPARα was lower in CE than in LW animals (P < 0.01, P < 0.05, P < 0.01, P < 0.01, respectively). In liver, no molecule differed between breeds. The expression of both AdipoRs in visceral and subcutaneous adipose tissues was lower in CE pigs (P < 0.01). In brain, AdipoR1 and AMPKα expression was lower in CE pigs (P < 0.01), whereas AdipoR2 tended to be lower in CE than LW pigs (P = 0.05). In conclusion, our results suggest that tissue-specific downregulation of Adiponectin, AdipoRs, and of the key molecules of energy metabolism may be associated with the tendency of CE pigs to accumulate fat.     

Expression of adiponectin and its receptors in swine

Adiponectin is an adipocyte-derived hormone that plays an important role in lipid metabolism and glucose homeostasis. Objectives of this study were 1) to determine the presence and distribution of adiponectin and its receptors 1 and 2 (adipoR1 and adipoR2) in porcine tissues; 2) to characterize pig adiponectin, adipoR1, and adipoR2 mRNA levels in various fat depots from three different breeds of pigs; and 3) to study, in stromal-vascular cell culture, the effects of leptin and tumor necrosis factor-alpha (TNFalpha) on pig adiponectin, adipoR1, and adipoR2 gene expression. To this end, fat Chinese Upton Meishan (UM, n = 10), lean Ham Line (HL, n = 10), and Large White (LW, n = 10) gilts were used. We report the isolation of partial cDNA sequences of pig adipoR1 and adipoR2. Porcine-deduced AA sequences share 97 to 100% homology with human and murine sequences. Pig adipoR1 mRNA is abundant in skeletal muscle, visceral fat, and s.c. fat tissues, whereas adipoR2 mRNA is predominantly expressed in liver, heart, skeletal muscle, and visceral and s.c. fat tissues. Pig adiponectin mRNA levels in s.c. and visceral fat tissues were not associated with plasma insulin and glucose in fasting animals. Subcutaneous (r = -0.44, P < 0.05), visceral (r = -0.43, P < 0.05), and total body fat (r = -0.42, P < 0.05) weights were negatively correlated with adiponectin mRNA levels measured in visceral, but not s.c., fat. Pig adipoR1 and adipoR2 mRNA levels, in visceral fat, were less expressed in fat UM gilts than in the lean HL gilts (P < 0.05). Inverse associations were found between s.c. (r = -0.57, P < 0.01), visceral (r = -0.46, P < 0.05), and total body fat (r = -0.56, P < 0.01) weights and adipoR2 mRNA levels in visceral fat only. We were unable to find such associations for adipoR1 mRNA levels in the overall gilt population. The current study demonstrated that TNFalpha downregulates adiponectin and adipoR2, but not adi-poR1, mRNA levels in stromal-vascular cell culture. Moreover, leptin significantly decreased adiponectin mRNA levels, whereas there was no effect on adiponectin receptors. We conclude that adiponectin and adi-poR2 mRNA levels, but not adipoR1, are modulated in pig visceral fat tissues. Furthermore, our results indicate that TNFalpha interferes with adiponectin function by downregulation of adipoR2 but not of adipoR1 mRNA levels in pigs.     

Differential effects of propionate or β-hydroxybutyrate on genes related to energy balance and insulin sensitivity in bovine white adipose tissue explants from a subcutaneous and a visceral depot

Ruminants rely on short-chain fatty acids (SCFA) as principal energy source. Herein, we compared the effects of propionate, β-hydroxybutyrate (BHB) and insulin on mRNA abundance of energy balance-related genes by short-term incubation (4 h) in bovine subcutaneous (SC) and retroperitoneal (RP) adipose tissue (AT) explants in vitro. Propionate either significantly (p < 0.05), or as a trend (p ≤ 0.1) affected mRNA abundance of genes such as adiponectin system in both depots in treated samples versus controls. Propionate increased adiponectin receptor 1 (AdipoR1) and AdipoR2 mRNA only in SC AT. β-hydroxybutyrate decreased mRNA abundance of adiponectin and AdipoR1 in SC AT as a trend. The mRNA abundance of free fatty acid receptor 2/3 (FFAR2/3) and other genes of interest (GOI) was increased during differentiation in bovine preadipocyte culture. The mRNA abundance of all the GOI remained unchanged after short-term insulin stimulation. In total, propionate, BHB or insulin during short-term treatment exert divergent effects on the mRNA abundance of GOI in both depots in vitro. Our results indicate that the bovine adiponectin system might be more sensitive to propionate than to BHB. We demonstrated the presence of FFAR2/3 mRNA not only in both AT depots but also in differentiating preadipocytes isolated from bovine SC AT. Therefore, we established that SCFA are able to exert insulin-independent effects on bovine adipose tissue, which might be independent from propionate uptake-related events.     

Transition period-related changes in the abundance of the mRNAs of adiponectin and its receptors,of visfatin,and of fatty acid binding receptors in adipose tissue of high-yielding dairy cows

Adipose tissue expresses adipokines, which are involved in regulation of energy expenditure, lipid metabolism, and insulin sensitivity. To adapt for the transition from pregnancy to lactation, particularly in high-yielding dairy cows, adipokines, their receptors, and particular G-protein coupled receptors (GPRs) are of potential importance. Signaling by GPR 41 stimulates leptin release via activation by short-chain fatty acids; GPR 43/109A inhibits lipolysis, and GPR 109A thereby mediates the lipid-lowering effects of nicotinic acid and β–hydroxybutyrate. The aim of this study was to compare the mRNA expression of adiponectin and visfatin, adiponectin receptors 1 and 2 (AdipoR1/2), leptin receptor (obRb), insulin receptor as of the aforementioned GPRs during the transition period in high-yielding dairy cows. Biopsies from subcutaneous fat and blood samples were obtained from 10 dairy cows 1 week before and 3 weeks after calving. For AdipoR1 and AdipoR2 mRNA abundance as well as for leptin concentrations in plasma, a reduction (P ≤ .05) was observed postpartum; for visfatin and putative GPR 109A mRNA abundance in adipose tissue, there was a trend (P < .1) for analogous changes. In contrast, the mRNA content of obRb and GPR 41 in adipose tissue was higher (P ≤ .05) in samples from early lactation than in those from late gestation. Our results indicate decreasing adiponectin sensitivity in adipose tissue after calving, which might be involved in the reduced insulin sensitivity of adipose tissue during early lactation. In addition, visfatin, GPR 41, and GPR 109A may further modulate insulin sensitivity.     

ORIGINAL ARTICLE: mRNA abundance of adiponectin and its receptors,leptin and visfatin and of G‐protein coupled receptor 41 in five different fat depots from sheep

Adipose tissue (AT) expresses adipokines, which are involved in the regulation of energy expenditure, lipid metabolism and insulin sensitivity. Visceral (v.c.) and subcutaneous (s.c.) depots largely differ concerning their metabolic characteristics as to the control of lipolysis and the sensitivity to insulin. The adipokines adiponectin, leptin and visfatin influence lipolysis and insulin sensitivity. Signalling by G‐protein coupled receptor 41 (GPR 41) stimulates leptin release via activation by short‐chain fatty acids. We hypothesized that the metabolic differences between v.c. and s.c. fat depots may also apply to the expression of adiponectin, its receptors, leptin, visfatin, insulin receptor (IR) and GPR 41. Therefore, we aimed to compare the mRNA expression of adiponectin, leptin and visfatin, of the adiponectin receptors 1 and 2 (AdipoR1/2) and IR as well of GPR 41 between several s.c. and v.c. fat depots in sheep. Samples from 10 rams were collected at slaughter (40 kg BW) from three s.c. depots, i.e. close to sternum (s.c.S), close to withers (s.c.W), and at the base of tail (s.c.T), and from two v.c. depots, i.e. from perirenal (v.c.P) and omental (v.c.O) fat. The mRNAs of both adiponectin receptors, as well as IR and putative GPR 41, were higher expressed in v.c. fat than in s.c. fat (p ≤ 0.05). Leptin mRNA abundance was greater in s.c. than in v.c. fat (mean ± SEM: s.c.: 2.55 ± 0.81; v.c.: 0.66 ± 0.21) and also differed among the five separately measured fat depots. Our results show differences in mRNA abundance for leptin, AdipoR1 and R2, as well as for IR and GPR 41 in s.c. compared with v.c. fat, thus confirming the need for individual consideration of distinct fat depots, when aiming to characterize adipose functions in ruminants.     

Regulation of hepatic peroxisome proliferator‐activated receptor α expression but not adiponectin by dietary protein in finishing pigs

Soy protein regulates adiponectin and peroxisome proliferator‐activated receptor α (PPARα) in some species, but the effect of dietary soy protein on adiponectin and PPARα in the pig has not been studied. Therefore, the objective of this study was to determine whether soya bean meal reduction or replacement influences serum adiponectin, adiponectin mRNA, serum metabolites and the expression of PPARα and other genes involved in lipid deposition. Thirty‐three pigs (11 pigs per treatment) were subjected to one of three dietary treatments: (i) reduced crude protein (CP) diet containing soya bean meal (RCP‐Soy), (ii) high CP diet containing soya bean meal (HCP‐Soy) or (iii) high CP diet with corn gluten meal replacing soya bean meal (HCP‐CGM) for 35 days. Dietary treatment had no effect on overall growth performance, feed intake or measures of body composition. There was no effect of dietary treatment on serum adiponectin or leptin. Dietary treatment did not affect the abundance of the mRNAs for adiponectin, PPARα, PPARγ2, lipoprotein lipase or fatty acid synthase in adipose tissue. The mRNA expression of PPARα, PPARγ2, lipoprotein lipase or fatty acid synthetase in loin muscle was not affected by dietary treatment. In liver tissue, the relative abundance of PPARα mRNA was greater (p < 0.05) in pigs fed the HCP‐Soy diets when compared to pigs fed RCP‐Soy or HCP‐CGM diets. Hepatic mRNA expression of acyl‐CoA oxidase or fatty acid synthase was not affected by dietary treatment. Western blot analysis indicated that hepatic PPARα protein levels were decreased (p < 0.05) in pigs fed the RCP‐Soy diets when compared to pigs fed the HCP‐Soy diets. These data suggest that increasing the soy protein content of swine diets increases hepatic expression of PPARα without associated changes in body composition.     

Plasma leptin and mRNA expression of lipogenesis and lipolysis-related factors in bovine adipose tissue around parturition

The objective was to study changes in plasma leptin concentration parallel to changes in the gene expression of lipogenic- and lipolytic-related genes in adipose tissue of dairy cows around parturition. Subcutaneous fat biopsies were taken from 27 dairy cows in week 8 antepartum (a.p.), on day 1 postpartum (p.p.) and in week 5 p.p. Blood samples were assayed for concentrations of leptin and non-esterified fatty acids (NEFA). Subcutaneous adipose tissue was analysed for mRNA abundance by real-time qRT-PCR encoding for leptin, adiponectin receptor 1 (AdipoR1), adiponectin receptor 2 (AdipoR2), hormones-sensitive lipase (HSL), perilipin (PLIN), lipoprotein lipase (LPL), acyl-CoA synthase long-chain family member 1 (ACSL1), acetyl-CoA carboxylase (ACC), fatty acid synthase (FASN) and glycerol-3-phosphate dehydrogenase 2 (GPD2). Body weight and body condition score of the cows were lower after parturition than before parturition. The calculated energy balance was negative in week 1 and 5 p.p., with higher negative energy balance in week 1 p.p. compared with that in week 5 p.p. On day 1 p.p., highest concentrations of NEFA (353.3 μmol/l) were detected compared with the other biopsy time-points (210.6 and 107.7 μmol/l, in week 8 a.p., and week 5 p.p. respectively). Reduced plasma concentrations of leptin during p.p. when compared with a.p. would favour increasing metabolic efficiency and energy conservation for mammary function and reconstitution of body reserves. Lower mRNA abundance of ACC and FASN expression on day 1 p.p. compared with other biopsy time-points suggests an attenuation of fatty acid synthesis in subcutaneous adipose tissue shortly after parturition. Gene expression of AdipoR1, AdipoR2, HSL, PLIN, LPL, ACSL1 and GPD2 was unchanged over time.     

Partial sequencing and expression of genes involved in glucose metabolism in adipose tissues and skeletal muscle of healthy cats

Impaired insulin sensitivity is increasingly recognised in cats, but sequences of genes involved in insulin-signalling are largely undetermined in this species. In this study, extended feline mRNA sequences were determined for the adiponectin, glucose transporter-1 (GLUT1), GLUT4, peroxisome proliferative activated receptor-gamma1 (PPARgamma1), PPARgamma2, plasminogen activator inhibitor-1 (PAI-1), monocyte chemoattractant protein-1 (MCP-1) and insulin receptor genes. Conserved dog-specific primers identified from human-dog mRNA alignments were used to amplify feline cDNA in the polymerase chain reaction (PCR). The feline sequences determined by this method were used to design feline-specific primers suitable for real-time PCR for quantification of gene expression in insulin sensitive tissues of healthy cats. Partial sequences of feline mRNAs had 86-95% identity with dog and human genes. Expression of adiponectin, GLUT1, GLUT4, PPARgamma1, PPARgamma2, PAI-1 and insulin receptor mRNA was detected and quantified in subcutaneous and visceral fat and skeletal muscle, whereas MCP-1 mRNA was detected in adipose tissue but not in skeletal muscle. Further characterisation of genes related to glucose metabolism in cats will provide additional insights into insulin-signalling mechanisms in this species.     

A comparison of thiazolidinedione-induced adipogenesis and myogenesis in stromal-vascular cells from subcutaneous adipose tissue or semitendinosus muscle of postnatal pigs

This study compared the adipogenic potential of porcine stromal-vascular (S-V) cells from semitendinosus muscles and s.c. adipose tissue using thiazolidinediones. Stromal-vascular cells were obtained from s.c. adipose tissue and both semitendinosus muscles from 5- to 7-d-old pigs after collagenase digestion. Preadipocyte recruitment was measured using immunohistological evaluation for AD-3, a preadipocyte antibody. Ciglitazone increased the number of preadipocytes in adipose tissue but not semitendinosus muscle S-V cell cultures, whereas 10 microM troglitazone increased preadipocyte abundance in both adipose and muscle S-V cultures by approximately 3-fold (P < 0.05). Increasing troglitazone doses did not further increase preadipocyte number. Increases in preadipocytes were paralleled by increases in CCAAT/enhancer-binding protein alpha (C/EBPalpha) and peroxisome proliferator-activated receptor gamma (PPARgamma) positive cells in adipose tissue S-V cultures, whereas PPARgamma-reactive but not C/EBPalpha-reactive cells were increased in muscle S-V cultures treated with 10 microM troglitazone. Additionally, troglitazone treatment did not increase lipid content in s.c. adipose tissue or muscle S-V cell cultures. Cells plated on laminin-precoated culture dishes were used to determine whether troglitazone influenced adipogenesis or myogenesis in cocultures from muscle S-V cells. There was no effect on the number of myotubes or the average number of nuclei per myotube, suggesting myogenesis was not impaired by troglitazone treatment. These results suggest that regulation of intramuscular adipogenesis differs from that of subcutaneous adipogenesis.     

Research Progress on Adiponectin and its Receptors and their Roles in Reproduction

Adiponectin is a special protein which is secreted by adipose tissue and has many kinds of biological functions that play an important role in enhancing fatty acid oxidation,inflammation reaction and anti diabetes ect.Adiponectin mediated by AdipoR1 and AdipoR2 via AMPK,PPAR,p38MAPK signal pathway plays an important role.Adiponectin and its receptors AdipoR1 and AdipoR2 express in many tissues,AdipoR1 is mainly expressed in muscle tissue,AdipoR2 is highly expressed in liver tissue.In addition,adiponectin and its receptors also expressed in the hypothalamus,pituitary,uterus,embryo and other reproductive glands and tissues,which indicate that adiponectin plays an important role in regulating animal reproduction and embryo growth and development.     

脂联素及其受体的研究进展及在生殖中的作用

脂联素是一种由脂肪组织分泌的具有多种生物学功能的特殊蛋白,在增强脂肪酸氧化、抗炎症反应、抗糖尿病等方面起重要作用。脂联素通过AdipoR1和AdipoR2这两种受体的介导经过AMPK、PPAR、p38MAPK等信号通路来发挥生物学作用。脂联素及其受体AdipoR1和AdipoR2能在多种组织器官中表达,AdipoR1主要在肌肉组织中表达,AdipoR2则高表达于肝脏组织。此外,脂联素及其受体还能在下丘脑、垂体、子宫、胚胎等多种生殖腺和生殖组织中表达,说明脂联素在调控动物生殖及胚胎生长发育方面起重要作用。     

Expression of adiponectin and its receptors (AdipoR1 and AdipoR2) in chicken ovary: potential role in ovarian steroidogenesis

Adiponectin and its receptors (AdipoR1 and AdipoR2) mRNAs are expressed in various chicken tissues including ovary. However, the cellular expression and the role of adiponectin system have never been investigated in chicken ovary. Here, we have shown that the level of adiponectin mRNA is about 10- to 30-fold higher (p < 0.001) in theca cells than in granulosa cells from each hierarchical yellow follicle studied (F4–F1). In contrast, the level of AdipoR1 mRNA expression was about two-fold lower in theca cells than in granulosa cells (p < 0.05) whereas those of AdipoR2 was similar in both ovarian cells. Whereas expression of adiponectin mRNA increased with follicular differentiation in theca cells, it decreased in granulosa cells. In contrast, mRNA expression of AdipoR1 and AdipoR2 in both theca and granulosa cells remained stable during yellow follicle development. To determine whether adiponectin is involved in the ovarian steroidogenesis, LH (100 ng/ml)-, FSH (100 ng/ml)- and IGF-1 (100 ng/ml)-induced progesterone production was measured in absence or presence of human recombinant adiponectin (10 μg/ml) for 36 h in cultured granulosa cells from F1, F2 and mixed F3 and F4 follicles. In absence of LH, FSH and IGF-1, adiponectin treatment had no effects on progesterone production whatever vitollegenic follicle studied. However, it increased by about two-fold IGF-1-induced progesterone secretion in F2 and F3/4 follicles whereas it halved progesterone production in response to gonadotropins (LH and FSH) in F3/4 follicles. Thus, in chicken, adiponectin, mainly expressed in theca cells, could exert paracrine or autocrine effect on the ovarian steroidogenesis.     

Expression of Adiponectin and its Receptors in the Porcine Hypothalamus During the Oestrous Cycle

Adiponectin is a hormonal link between obesity and reproduction, and its actions are mediated by two types of receptors: adiponectin receptor 1 (AdipoR1) and adiponectin receptor 2 (AdipoR2). This study compares the expression levels of adiponectin and adiponectin receptor mRNAs and proteins in selected areas of the porcine hypothalamus responsible for GnRH production and secretion: the mediobasal hypothalamus (MBH), pre‐optic area (POA) and stalk median eminence (SME). The tissue samples were harvested on days 2–3, 10–12, 14–16 and 17–19 of the oestrous cycle. Adiponectin mRNA expression in MBH was significantly lower on days 14–16, whereas in SME, the most pronounced gene expression was found on days 2–3 of the cycle (p < 0.05). Adiponectin protein in MBH was most abundant on days 17–19 and in POA on days 2–3 (p < 0.05). Adiponectin protein expression in SME was at similar level throughout the most of the cycle with a statistically significant drop (p < 0.05) on days 14–16. AdipoR1 gene expression in POA was potentiated on days 2–3 and 10–12 of the oestrous cycle (p < 0.05). In SME, the highest AdipoR1 mRNA expression was noted on days 2–3 (p < 0.05). The concentrations of the AdipoR1 protein in POA were similar throughout the luteal phase (days 2–14 of the cycle), and they decreased on days 17–19 (p < 0.05). In SME, AdipoR1 protein expression peak occurred on days 2–3 (p < 0.05). The expression patterns of the AdipoR2 gene in MBH, POA and SME revealed the highest mRNA levels on days 2–3 of the cycle (p < 0.05). The highest content of AdipoR2 protein in MBH was reported on days 2–3 (p < 0.05), while in POA on days 17–19 and in SME on days 10–12 and 14–16 (p < 0.05). This study demonstrated that adiponectin and adiponectin receptor mRNAs and proteins are present in the porcine hypothalamus and that their expression levels are determined by the pig's endocrine status related to the oestrous cycle.     

Birth weight and gender determine expression of adipogenic, lipogenic and adipokine genes in perirenal adipose tissue in the young adult sheep

Epidemiological studies have demonstrated that low birth weight is associated with an increased incidence of visceral obesity and metabolic disorders in later life. In the present study, we have determined the impact of birth weight and gender on gene expression in visceral adipose tissue (VAT) in the young adult sheep. Lambs (n=19, birth weight range 2.6-7.55 kg) were born at term and growth monitored for 22.4+/-0.2 weeks, when body composition was determined by Dual X-ray Absorptiometry (DXA) and samples of VAT and subcutaneous (SCAT) adipose tissue collected. Plasma samples were collected at post-mortem for the determination of free fatty acids (FFA), glucose and insulin concentrations. Peroxisome-Proliferator Activated Receptor-gamma (PPARgamma), glycerol-3-phosphate dehydrogenase (G3PDH), lipoprotein lipase (LPL), adiponectin and leptin mRNA expression was determined by qRT-PCR. Fractional growth rate in postnatal weeks 1-3 was inversely related to birth weight in both males and females (R2=0.22, P<0.05, n=19). PPARgamma mRNA expression in VAT, but not SCAT, was inversely related to birth weight (R2=0.60, P<0.01, n=18). In males, but not females, PPARgamma mRNA in VAT was directly related to G3PDH mRNA expression (R2=0.69, P<0.01, n=9). Plasma FFA concentrations were inversely related to birth weight in both males and females (R2=0.22, P<0.05, n=19). These findings demonstrate that low birth weight is associated with an increased expression of a key adipogenic factor in visceral adipose tissue in young adulthood. In males, this is associated with an increased expression of lipogenic genes, and this may contribute to the increased propensity for visceral obesity in low birth weight males compared to females.     

猪FoxO1基因cDNA部分序列的克隆及其组织表达

根据人、黑猩猩及大鼠等物种FoxO1基因同源序列设计引物,利用RT-PCR方法从猪肝脏中克隆FoxO1基因cDNA的部分序列,组织特异性表达分析表明,FoxO1基因在1日龄和9月龄猪的肝、肺、肾、脾、心、胃、皮下脂肪、内脏脂肪、背最长肌和股四头肌等组织中均表达,只是表达丰度随发育阶段和组织的不同有所差异。1日龄猪的内脏脂肪中FoxO1的表达丰度最高,心脏和骨骼肌中相对较低;而9月龄猪的脾脏中FoxO1相对表达丰度最高,明显高于免疫机能尚未完全建立的初生猪,显示出FoxO1可能在机体的免疫调节中起一定作用,另外,9月龄猪的FoxO1表达丰度不仅在平滑肌和骨骼肌中有显著差异,而且在不同类型的骨骼肌中也存在显著差异,显示出FoxO1的表达可能与骨骼肌类型和运动强度有关。