ABSTRACT: Local crosstalk between the lipid deposition and skeletal muscle growth inhibition from Bama minipig obesity model by high-fat high-sucrose diet
Project description:The underlying mechanism of how the atopic lipids in skeletal muscle affect muscle growth remains elusive. Here we chose miniature Bama swine as our model to mimick human obesity and co-associated metabolic disorders by long time diet induction and study how the atopic fat accumulation in skeletal muscle influence muscle function. After 23 months high-fat high-sucrose diet (HFHSD) fed, the model minipig model of obesity accompanied with metabolic disorders like human, and they had increased body weight and extensive lipids deposition in adipose tissues (AT) and non-AT, especially in skeletal muscle. Further more, the mass of skeletal reduced greatly and the small area (0-2000μm2) muscle reduced after diet induced. The average fiber area of Gastroc reduced 25.2%, but no significant changes appeared in the other skeletal muscles. Antioxidant capacity of skeletal muscle also reduced. Microarray profiles showed genes related to fat deposition promotion (Peroxisome proliferator activated receptor γ, CCAAT/enhancer-binding protein α and apolipoprotein E), muscle growth inhibition (myostatin and p21) up regulated, and some other muscle cell differentiation related genes (myoD) down regulated. Meanwhile, adipokines like adiponectin and 11b-hydroxysteroid dehydrogenase type 1 (11βHSD1) which partake in the crosstalk between AT and skeletal muscles rose up. We draw a clear potential crosstalk pathway that, increased 11βHSD1 secreted by excess AT will promote the expression of the major inhibitor MSTN by activating corticosterone to cortisol, leading to the growth inhibition of skeletal muscle. Overall, this research announces how obesity affects skeletal muscle growth in a crosstalk sight. Male and female Bama minipigs, aged 6 months at the start of the study, were divided into the following two groups for 23 months of treatment. Bama minipigon control (CD group, N=3) were fed standard pig chow. The experimental group (N=6) were fed high-fat high-sucrose diet (53% basal diet, 37% sucrose, 10% lard, HFHSD).
Project description:The underlying mechanism of how the atopic lipids in skeletal muscle affect muscle growth remains elusive. Here we chose miniature Bama swine as our model to mimick human obesity and co-associated metabolic disorders by long time diet induction and study how the atopic fat accumulation in skeletal muscle influence muscle function. After 23 months high-fat high-sucrose diet (HFHSD) fed, the model minipig model of obesity accompanied with metabolic disorders like human, and they had increased body weight and extensive lipids deposition in adipose tissues (AT) and non-AT, especially in skeletal muscle. Further more, the mass of skeletal reduced greatly and the small area (0-2000μm2) muscle reduced after diet induced. The average fiber area of Gastroc reduced 25.2%, but no significant changes appeared in the other skeletal muscles. Antioxidant capacity of skeletal muscle also reduced. Microarray profiles showed genes related to fat deposition promotion (Peroxisome proliferator activated receptor γ, CCAAT/enhancer-binding protein α and apolipoprotein E), muscle growth inhibition (myostatin and p21) up regulated, and some other muscle cell differentiation related genes (myoD) down regulated. Meanwhile, adipokines like adiponectin and 11b-hydroxysteroid dehydrogenase type 1 (11βHSD1) which partake in the crosstalk between AT and skeletal muscles rose up. We draw a clear potential crosstalk pathway that, increased 11βHSD1 secreted by excess AT will promote the expression of the major inhibitor MSTN by activating corticosterone to cortisol, leading to the growth inhibition of skeletal muscle. Overall, this research announces how obesity affects skeletal muscle growth in a crosstalk sight.
Project description:The anterior pituitary is the most important endocrine organ modulating animal postnatal growth, mainly by controlling growth hormone (GH) gene transcription, synthesis, and secretion. As an ideal model for animal postnatal growth studies, the Bama minipig is characterized as having a lower growth performance and fewer individual differences compared with larger pig breeds. In this study, anterior pituitaries from Bama minipig and Landrace pig were used for miRNA and mRNA expression profile analysis using miRNA microarrays and mRNA-seq. Consequently, a total of 222 miRNAs and 12,909 transcripts were detected, and both miRNAs and mRNAs in the two breeds showed high correlation (r > 0.97). Additionally, 41 differentially expressed miRNAs and 2,254 transcripts were identified. Pathways analysis indicated that 32 pathways significantly differed in the two breeds. Importantly, two GH-regulation-signalling pathways, cAMP and inositol 1, 4, 5-triphosphate (IP3), and multiple GH-secretion-related transcripts were significantly down-regulated in Bama minipigs. Moreover, target prediction by two algorithms (TargetScan and RNAhybrid) indicated that most miRNA–mRNA target pairs (63.68–71.33%) presented a negatively correlated expression pattern. A possible network among miRNAs, mRNAs, and GH-regulation pathways was also proposed. These data will be helpful in understanding the possible molecular mechanisms involved in animal postnatal growth. 2 pooled samples were analyzed. A pool of 3 pig anterior pituitary was used for Bama minpigs and Landrace pigs,respectively.
Project description:The anterior pituitary is the most important endocrine organ modulating animal postnatal growth, mainly by controlling growth hormone (GH) gene transcription, synthesis, and secretion. As an ideal model for animal postnatal growth studies, the Bama minipig is characterized as having a lower growth performance and fewer individual differences compared with larger pig breeds. In this study, anterior pituitaries from Bama minipig and Landrace pig were used for miRNA and mRNA expression profile analysis using miRNA microarrays and mRNA-seq. Consequently, a total of 222 miRNAs and 12,909 transcripts were detected, and both miRNAs and mRNAs in the two breeds showed high correlation (r > 0.97). Additionally, 41 differentially expressed miRNAs and 2,254 transcripts were identified. Pathways analysis indicated that 32 pathways significantly differed in the two breeds. Importantly, two GH-regulation-signalling pathways, cAMP and inositol 1, 4, 5-triphosphate (IP3), and multiple GH-secretion-related transcripts were significantly down-regulated in Bama minipigs. Moreover, target prediction by two algorithms (TargetScan and RNAhybrid) indicated that most miRNA–mRNA target pairs (63.68–71.33%) presented a negatively correlated expression pattern. A possible network among miRNAs, mRNAs, and GH-regulation pathways was also proposed. These data will be helpful in understanding the possible molecular mechanisms involved in animal postnatal growth. mRNA profiling in the anterior pituitary from two different pig breeds.2 pooled samples were analyzed. A pool of 3 pig anterior pituitary was used for Bama minpigs(YB) and Landrace pigs(YC),respectively.
Project description:The anterior pituitary is the most important endocrine organ modulating animal postnatal growth, mainly by controlling growth hormone (GH) gene transcription, synthesis, and secretion. As an ideal model for animal postnatal growth studies, the Bama minipig is characterized as having a lower growth performance and fewer individual differences compared with larger pig breeds. In this study, anterior pituitaries from Bama minipig and Landrace pig were used for miRNA and mRNA expression profile analysis using miRNA microarrays and mRNA-seq. Consequently, a total of 222 miRNAs and 12,909 transcripts were detected, and both miRNAs and mRNAs in the two breeds showed high correlation (r > 0.97). Additionally, 41 differentially expressed miRNAs and 2,254 transcripts were identified. Pathways analysis indicated that 32 pathways significantly differed in the two breeds. Importantly, two GH-regulation-signalling pathways, cAMP and inositol 1, 4, 5-triphosphate (IP3), and multiple GH-secretion-related transcripts were significantly down-regulated in Bama minipigs. Moreover, target prediction by two algorithms (TargetScan and RNAhybrid) indicated that most miRNA–mRNA target pairs (63.68–71.33%) presented a negatively correlated expression pattern. A possible network among miRNAs, mRNAs, and GH-regulation pathways was also proposed. These data will be helpful in understanding the possible molecular mechanisms involved in animal postnatal growth.
Project description:The anterior pituitary is the most important endocrine organ modulating animal postnatal growth, mainly by controlling growth hormone (GH) gene transcription, synthesis, and secretion. As an ideal model for animal postnatal growth studies, the Bama minipig is characterized as having a lower growth performance and fewer individual differences compared with larger pig breeds. In this study, anterior pituitaries from Bama minipig and Landrace pig were used for miRNA and mRNA expression profile analysis using miRNA microarrays and mRNA-seq. Consequently, a total of 222 miRNAs and 12,909 transcripts were detected, and both miRNAs and mRNAs in the two breeds showed high correlation (r > 0.97). Additionally, 41 differentially expressed miRNAs and 2,254 transcripts were identified. Pathways analysis indicated that 32 pathways significantly differed in the two breeds. Importantly, two GH-regulation-signalling pathways, cAMP and inositol 1, 4, 5-triphosphate (IP3), and multiple GH-secretion-related transcripts were significantly down-regulated in Bama minipigs. Moreover, target prediction by two algorithms (TargetScan and RNAhybrid) indicated that most miRNA–mRNA target pairs (63.68–71.33%) presented a negatively correlated expression pattern. A possible network among miRNAs, mRNAs, and GH-regulation pathways was also proposed. These data will be helpful in understanding the possible molecular mechanisms involved in animal postnatal growth.
Project description:Aims/hypothesis: While lipid deposition in skeletal muscle is considered to be involved in obesity-associated insulin resistance, neutral intramyocellular lipid (IMCL) accumulation per se does not necessarily induce insulin resistance. We previously demonstrated that overexpression of the lipid droplet coat protein perilipin 2 augments intramyocellular lipid content while improving insulin sensitivity. Another member of the perilipin family, perilipin 5 (PLIN5), is predominantly expressed in oxidative tissues like skeletal muscle. Here we investigated the effects of PLIN5 overexpression M-bM-^@M-^S in comparison with effects of PLIN2 M-bM-^@M-^S on skeletal muscle lipid levels, gene expression profiles and insulin sensitivity. Methods: Gene electroporation was used to overexpress PLIN5 in tibialis anterior muscle of rats fed a high fat diet. Eight days after electroporation, insulin-mediated glucose uptake in skeletal muscle was measured by means of a hyperinsulinemic euglycemic clamp. Electron microscopy, fluorescence microscopy and lipid extractions were performed to investigate IMCL accumulation. Gene expression profiles were obtained using microarrays. Results: TAG storage and lipid droplet size increased upon PLIN5 overexpression. Despite the higher IMCL content, insulin sensitivity was not impaired and DAG and acylcarnitine levels were unaffected. In contrast to the effects of PLIN2 overexpression, microarray data analysis revealed a gene expression profile favoring FA oxidation and improved mitochondrial function. Conclusions/interpretation: Both PLIN2 and PLIN5 increase neutral IMCL content without impeding insulin-mediated glucose uptake. As opposed to the effects of PLIN2 overexpression, overexpression of PLIN5 in skeletal muscle promoted expression of a cluster of genes under control of PPARM-NM-1 and PGC1M-NM-1 involved in FA catabolism and mitochondrial oxidation. Rats received a high fat diet for 3 weeks; 2 weeks after start of the diet intervention Plin5 (OXPAT) or Plin2 (ADRP) were overexpressed in either the right or left tibialis anterior muscle. One week later pooled tibialis anterior muscle samples were analysed on microarrays.
Project description:Identify genes in the skeletal muscle whose expression is under genetic regulation in the Hybrid Mouse Diversity Panel (HMDP). The HMDP comprises classical inbred and recombinant inbred wild type mice. The neqc-normalized values of genes were used for genome wide association. These data are used to identify candidate genes at loci associated with obesity and dietary responsiveness. GWAS for expression of skeletal muscle in inbred strains fed chow diet for 8 weeks followed by high-fat/high-sucrose diet 8 weeks
Project description:In order to study the heart disorder that the long term, high energy diet caused, Bama miniature pigs were fed a high-fat, high-sucrose diet for 23 months. These pigs developed symptoms of metabolic syndrome and showed cardiac steatosis and hypertrophy with a greatly increased heart weight (1.82-fold, P<0.05) and heart volume (1.60-fold, P<0.05) compared with the control pigs. To understand the molecular mechanisms of cardiac steatosis and hypertrophy, nine pig heart cRNA samples were hybridized to porcine GeneChips. The control group consisted of 6 Bama pigs fed a control diet, and the HFHSD group comprised 6 pigs that were induced with a HFHS diet, which included 37% sucrose, 53% control diet and 10% pork lard. The pigs were fed twice every day and provided water ad libitum for 23 months. The pigs were fasted for 12 hours and euthanized with ketamine and xylazine. Pig hearts from the HFHSD group pigs (120, 126, 138, 140, 144, and 146) and three control group pigs (157, 159, and 161) were sampled and preserved in liquid nitrogen and then for RNA extraction and hybridization on Affymetrix microarrays.