Palmitoleic acid (n-7) increases white adipocyte lipolysis and lipase content in a PPARα-dependent manner

2013 ◽  
Vol 305 (9) ◽  
pp. E1093-E1102 ◽  
Author(s):  
Andressa Bolsoni-Lopes ◽  
William T. Festuccia ◽  
Talita S. M. Farias ◽  
Patricia Chimin ◽  
Francisco L. Torres-Leal ◽  
...  

We investigated whether palmitoleic acid, a fatty acid that enhances whole body glucose disposal and suppresses hepatic steatosis, modulates triacylglycerol (TAG) metabolism in adipocytes. For this, both differentiated 3T3-L1 cells treated with either palmitoleic acid (16:1n7, 200 μM) or palmitic acid (16:0, 200 μM) for 24 h and primary adipocytes from wild-type or PPARα-deficient mice treated with 16:1n7 (300 mg·kg−1·day−1) or oleic acid (18:1n9, 300 mg·kg−1·day−1) by gavage for 10 days were evaluated for lipolysis, TAG, and glycerol 3-phosphate synthesis and gene and protein expression profile. Treatment of differentiated 3T3-L1 cells with 16:1n7, but not 16:0, increased basal and isoproterenol-stimulated lipolysis, mRNA levels of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) and protein content of ATGL and pSer660-HSL. Such increase in lipolysis induced by 16:1n7, which can be prevented by pharmacological inhibition of PPARα, was associated with higher rates of PPARα binding to DNA. In contrast to lipolysis, both 16:1n7 and 16:0 increased fatty acid incorporation into TAG and glycerol 3-phosphate synthesis from glucose without affecting glyceroneogenesis and glycerokinase expression. Corroborating in vitro findings, treatment of wild-type but not PPARα-deficient mice with 16:1n7 increased primary adipocyte basal and stimulated lipolysis and ATGL and HSL mRNA levels. In contrast to lipolysis, however, 16:1n7 treatment increased fatty acid incorporation into TAG and glycerol 3-phosphate synthesis from glucose in both wild-type and PPARα-deficient mice. In conclusion, palmitoleic acid increases adipocyte lipolysis and lipases by a mechanism that requires a functional PPARα.

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Tuo Deng ◽  
Wenwen Zhang ◽  
Yanling Zhang ◽  
Mengqi Zhang ◽  
Zhikun Huan ◽  
...  

Abstract Background As the incidence of secretory osteoporosis has increased, bone loss, osteoporosis and their relationships with thyroid-stimulating hormone (TSH) have received increased attention. In this study, the role of TSH in bone metabolism and its possible underlying mechanisms were investigated. Methods We analyzed the serum levels of free triiodothyronine (FT3), free thyroxine (FT4), and TSH and the bone mineral density (BMD) levels of 114 men with normal thyroid function. In addition, osteoblasts from rat calvarial samples were treated with different doses of TSH for different lengths of time. The related gene and protein expression levels were investigated. Results A comparison of the BMD between the high-level and low-level serum TSH groups showed that the TSH serum concentration was positively correlated with BMD. TSH at concentrations of 10 mU/mL and 100 mU/mL significantly increased the mRNA levels of ALP, COI1 and Runx2 compared with those of the control (P < 0.05, P < 0.01). Bone morphogenetic protein (BMP)2 activity was enhanced with both increased TSH concentration and increased time. The protein levels of Runx2 and osterix were increased in a dose-dependent manner. Conclusions The circulating concentrations of TSH and BMD were positively correlated with normal thyroid function in males. TSH promoted osteoblast proliferation and differentiation in rat primary osteoblasts.


Endocrinology ◽  
2004 ◽  
Vol 145 (12) ◽  
pp. 5525-5531 ◽  
Author(s):  
Gary M. Leong ◽  
Sofia Moverare ◽  
Jesena Brce ◽  
Nathan Doyle ◽  
Klara Sjögren ◽  
...  

Abstract Suppressors of cytokine signaling (SOCS) are important negative regulators of cytokine action. We recently reported that estrogen stimulates SOCS-2 expression and inhibits GH signaling in kidney cells. The effects of estrogen on SOCS expression in other tissues are unclear. The aim of this study was to investigate in vivo and in vitro whether estrogen affected SOCS expression in the liver, a major target organ of GH. The in vivo hepatic effects of estrogen on ovariectomized mice lacking estrogen receptor (ER)-α, ERβ, or both and their wild-type littermates were examined by DNA microarray analysis. In vitro, the effects of estrogen on SOCS expression in human hepatoma cells were examined by reverse transcription quantitative PCR. Long-term (3 wk) estrogen treatment induced a 2- to 3-fold increase in hepatic expression of SOCS-2 and -3 in wild-type and ERβ knockout mice but not in those lacking ERα or both ER subtypes. Short-term treatment (at 24 h) increased the mRNA level of SOCS-3 but not SOCS-2. In cultured hepatoma cells, estrogen increased SOCS-2 and -3 mRNA levels by 2-fold in a time- and dose-dependent manner (P &lt; 0.05). Estrogen induced murine SOCS-3 promoter activity by 2-fold (P &lt; 0.05) in constructs containing a region between nucleotides −1862 and −855. Moreover, estrogen and GH had additive effects on the SOCS-3 promoter activity. In summary, estrogen, via ERα, up-regulated hepatic expression of SOCS-2 and -3, probably through transcriptional activation. This indicates a novel mechanism of estrogen regulation of cytokine action.


1996 ◽  
Vol 17 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Sheryl K. Brining ◽  
Collins R. Jones ◽  
Michael C.J. Chang

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Badr Khbouz ◽  
François Lallemand ◽  
Pascal Rowart ◽  
Laurence Poma ◽  
Agnès Noel ◽  
...  

Abstract Background and Aims Whole-body irradiation has been suggested to induce renal ischemic preconditioning (RIP) in rodent models, possibly via neo-angiogenesis. First, we comprehensively investigate the pathways involved in kidney-centered irradiation. Next, we assess the functional and structural impact of kidney-centered irradiation applied before ischemia/reperfusion (I/R) injury. Finally, we test whether Sunitinib-mediated inhibition of the neo-angiogenesis prevents irradiation-associated RIP. Method Experiment 1: Unilateral irradiation of the left kidney (8.56 Gy) was performed in male 10-week-old wild-type C57bl/6 mice (n=10). One month later, total kidney RNA was extracted from irradiated and control (n=5) mice for comparative high-throughput RNA-Seq (using BaseSpace Sequence Hub Illumina). Functional enrichment analysis was performed using Database for Annotation, Visualization and Integrated Discovery (DAVID). Experiment 2: Two x-ray beams (225Kv, 13mA) specifically targeted both kidneys for a total dose of 8.56Gy. The right kidneys were removed and harvested, and the left kidneys undergo 30-minute ischemia followed by 48-hour reperfusion (n=8) at Days 7-14-21-28 post irradiation. Experiment 3: Following the same protocol of renal I/R at Day14, 3 groups of male 10-week-old wild-type C57bl/6 mice were compared (n=8 per group): 1/ bilateral pre-irradiation; 2/ bilateral pre-irradiation and gavage with Sunitinib from Day2 to Day13; 3/ control group without irradiation or gavage. Results Experiment 1: Comparative transcriptomics showed a significant up-regulation of various signaling pathways, including angiogenesis (HMOX1) and stress response (HSPA1A, HSPA1B). Expressions of angiogenesis markers (CD31, TGFb1, HMOX1) showed an increase at both mRNA (real-time qPCR) and protein (immuno-staining) levels in irradiated kidneys compared to controls (p&lt;0.01). Experiment 2: Following I/R, the blood urea nitrogen (BUN) and serum creatinine (SCr) levels were significantly lower in the irradiated animals compared to controls: (BUN: 86.2±6.8 vs. 454.5±27.2mg/dl; SCr: 0.1±0.01 vs. 1.7±0.2mg/dl, p&lt;0.01). The renal infiltration by CD11b-positive cells (187±32 vs. 477±20/mm²) and F4-80 macrophages (110±22 vs. 212±25/mm²) was significantly reduced in the irradiated group. The real-time qPCR mRNA levels of the angiogenic markers, TGFb1 and CD31, were significantly increased in the irradiated group compared to controls (p&lt;0,01). The CD31-immunostating (quantified by FiJi) was increased in irradiated mice compared to controls (p&lt;0.01). Experiment 3: One-way analysis of variance followed by Tukey’s test showed that, following I/R, the serum levels of BUN and SCr were lower in irradiated group compared to controls (BUN: 106.1±33.6 vs. 352.2±54.3mg/dl; SCr: 0.3±0.13 vs. 1±0.2mg/dl), and in irradiated group compared to the irradiated-exposed group to Sunitinib (BUN: 106.1±33.6 vs. 408.4±54.9mg/dl; SCr: 0.3±0.12 vs. 1.5±0.3mg/dl; p&lt;0.01). No difference was observed between the irradiated-exposed mice to Sunitinib and the controls. Conclusion Renal irradiation induces the activation of signaling pathways involved in angiogenesis in mice. Renal pre-irradiation leads to RIP, with preserved renal function and attenuated inflammation post I/R. Exposure to the anti-angiogenic drug Sunitinib post-irradiation prevents the irradiation-induced RIP.


Aquaculture ◽  
2020 ◽  
Vol 520 ◽  
pp. 734677 ◽  
Author(s):  
Thomas Cavrois-Rogacki ◽  
Andrew Rolland ◽  
Hervé Migaud ◽  
Andrew Davie ◽  
Oscar Monroig

Cell Reports ◽  
2019 ◽  
Vol 29 (12) ◽  
pp. 3974-3982.e4 ◽  
Author(s):  
Gérald Kénanian ◽  
Claire Morvan ◽  
Antonin Weckel ◽  
Amit Pathania ◽  
Jamila Anba-Mondoloni ◽  
...  

2009 ◽  
Vol 296 (4) ◽  
pp. F867-F874 ◽  
Author(s):  
Julia Lichtnekert ◽  
Volker Vielhauer ◽  
Daniel Zecher ◽  
Onkar P. Kulkarni ◽  
Sebastian Clauss ◽  
...  

Viral RNA or bacterial products can activate glomerular mesangial cells via a subset of Toll-like receptors (Tlr). Because Tlr2-deficient mice were recently found to have attenuated nephrotoxic serum nephritis (NSN), we hypothesized that endogenous Tlr agonists can activate glomerular mesangial cells. Primary mesangial cells from C57BL/6 mice expressed Tlr1-6 and Tlr11 mRNA at considerable levels and produced Il-6 when being exposed to the respective Tlr ligands. Exposure to necrotic cells activated cultured primary mesangial cells to produce Il-6 in a Tlr2/Myd88-dependent manner. Apoptotic cells activated cultured mesangial cells only when being enriched to high numbers. Apoptotic cell-induced Il-6 release was Myd88 dependent, and only purified apoptotic cell RNA induced Trif signaling in mesangial cells. Does Trif signaling contribute to disease activity in glomerulonephritis? To answer this question, we induced autologous NSN by injection of NS raised in rabbits in Trif-mutant and wild-type mice. Lack of Trif did not alter the functional and histomorphological abnormalities of NSN, including the evolution of anti-rabbit IgG and anti-rabbit-specific nephritogenic T cells. We therefore conclude that apoptotic cell RNA is a poor activator of Trif signaling in mesangial cells and that necrotic cells' releases rather activate mesangial cells via the Tlr2/Myd88 signaling pathway.


Endocrinology ◽  
2006 ◽  
Vol 147 (3) ◽  
pp. 1508-1516 ◽  
Author(s):  
David Patsouris ◽  
Janardan K. Reddy ◽  
Michael Müller ◽  
Sander Kersten

Peroxisome proliferator-activated receptors (PPARs) are transcription factors involved in the regulation of numerous metabolic processes. The PPARα isotype is abundant in liver and activated by fasting. However, it is not very clear what other nutritional conditions activate PPARα. To examine whether PPARα mediates the effects of chronic high-fat feeding, wild-type and PPARα null mice were fed a low-fat diet (LFD) or high-fat diet (HFD) for 26 wk. HFD and PPARα deletion independently increased liver triglycerides. Furthermore, in wild-type mice HFD was associated with a significant increase in hepatic PPARα mRNA and plasma free fatty acids, leading to a PPARα-dependent increase in expression of PPARα marker genes CYP4A10 and CYP4A14. Microarray analysis revealed that HFD increased hepatic expression of characteristic PPARα target genes involved in fatty acid oxidation in a PPARα-dependent manner, although to a lesser extent than fasting or Wy14643. Microarray analysis also indicated functional compensation for PPARα in PPARα null mice. Remarkably, in PPARα null mice on HFD, PPARγ mRNA was 20-fold elevated compared with wild-type mice fed a LFD, reaching expression levels of PPARα in normal mice. Adenoviral overexpression of PPARγ in liver indicated that PPARγ can up-regulate genes involved in lipo/adipogenesis but also characteristic PPARα targets involved in fatty acid oxidation. It is concluded that 1) PPARα and PPARα-signaling are activated in liver by chronic high-fat feeding; and 2) PPARγ may compensate for PPARα in PPARα null mice on HFD.


Sign in / Sign up

Export Citation Format

Share Document