Catecholaminergic innervation of white adipose tissue in Siberian hamsters

1995 ◽  
Vol 268 (3) ◽  
pp. R744-R751 ◽  
Author(s):  
T. G. Youngstrom ◽  
T. J. Bartness
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Neural Control ◽  
Fat Pad ◽  
Anterograde Transport ◽  
Siberian Hamsters ◽  
Lipid Stores ◽  
Catecholaminergic Innervation ◽  
Fat Pads

When Siberian hamsters are transferred from long summerlike days (LDs) to short winterlike days (SDs) they decrease their body weight, primarily as body fat. These SD-induced decreases in lipid stores are not uniform. Internally located white adipose tissue (WAT) pads are depleted preferentially of lipid, whereas the more externally located subcutaneous WAT pads are relatively spared. These data suggest a possible differential sympathetic neural control over catecholamine-induced lipolysis and that lipolytic rates are greater for internal vs. external WAT pads. Moreover, if these differential rates of lipolysis are due to differential sympathetic nervous system (SNS) drives on the pads, then fat pad-specific catecholaminergic innervation may exist. Therefore, we tested whether inguinal WAT (IWAT; an external pad) and epididymal WAT (EWAT; an internal pad) were innervated differentially. In addition, we tested whether norepinephrine (NE) turnover (TO) reflected the presumed greater SNS drive on EWAT vs. IWAT after SD exposure. Injections of fluorescent tract tracers [Fluoro-Gold or indocarbocyanine perchlorate (DiI)] demonstrated projections from the SNS ganglia T13-L3 to both fat pads. Retrograde labeling revealed a relatively separate pattern of distribution of labeled neurons in the ganglia projecting to each pad. In vivo anterograde transport of DiI resulted in labeling in both IWAT and EWAT that included staining around individual adipocytes and occasionally retrogradely labeled cells. The proportionately greater decrease in EWAT compared with IWAT mass after 5 wk of SD exposure was reflected in greater EWAT NE TO than found in their LD counterparts for this pad.(ABSTRACT TRUNCATED AT 250 WORDS)

Fat pad-specific compensatory mass increases after varying degrees of lipectomy in Siberian hamsters

1997 ◽  
Vol 273 (6) ◽  
pp. R2117-R2123 ◽  
Author(s):  
Mary Margaret Mauer ◽  
Timothy J. Bartness
Keyword(s):  
Adipose Tissue ◽  
Body Fat ◽  
White Adipose Tissue ◽  
Fat Content ◽  
Fat Pad ◽  
Siberian Hamsters ◽  
Long Day ◽  
Body Fat Content ◽  
Fat Removal ◽  
Fat Pads

Long day-housed Siberian hamsters show compensatory mass increases in inguinal (I) white adipose tissue (WAT) after epididymal WAT pad (EWAT) removal (x) but do not increase EWAT mass after IWATx. This study tested whether EWAT is specifically unresponsive to IWATx or whether EWAT lacks responsiveness to body fat deficits in general. We also tested whether the compensatory mass increases that occur after side-specific body fat removal are unilateral or bilateral. Therefore EWAT and/or IWAT was removed unilaterally or bilaterally. The compensatory changes in WAT mass by the intact fat pads were measured 12 wk later. EWAT did not compensate for removal of its contralateral mate. Retroperitoneal WAT and IWAT showed greater compensatory mass increases ipsilateral to the side of fat pad removal when EWAT or IWAT pads were removed unilaterally but not after removal of larger amounts of body fat. These results suggest the following: 1) in general, the greater the lipectomy-induced lipid deficit, the greater is the relative fat pad mass compensation; 2) the restoration of body fat content after lipectomy may involve mechanisms that can detect the side of the lipid deficit and enhance fat deposition on this side; and 3) EWAT does not show compensatory mass increases after lipectomy.

White adipose tissue sympathetic nervous system denervation increases fat pad mass and fat cell number

1998 ◽  
Vol 275 (5) ◽  
pp. R1488-R1493 ◽  
Author(s):  
Timothy G. Youngstrom ◽  
Timothy J. Bartness
Keyword(s):  
Nervous System ◽  
Adipose Tissue ◽  
Sympathetic Nervous System ◽  
White Adipose Tissue ◽  
Cell Number ◽  
Fat Pad ◽  
Fat Cell ◽  
Siberian Hamsters ◽  
Sympathetic Nervous

The sympathetic nervous system (SNS) drive on white adipose tissue (WAT) was varied to test its effects on fat cell number (FCN) under conditions in which lipolysis would be minimized and therefore partially separable from SNS trophic effects. The inguinal subcutaneous WAT (IWAT) pad of Siberian hamsters was chosen because 1) it is innervated by the SNS, 2) short day (SD) exposure increases its SNS drive (∼250%) without proportionately increasing lipolysis, and 3) surgical denervation eliminates its SNS innervation. IWAT was either unilaterally surgically or sham denervated, while the contralateral pad was left intact. In long day- or SD-exposed hamsters (11 wk), IWAT denervation decreased norepinephrine content (∼80%) and increased fat pad mass (∼200%) and FCN (∼250 and ∼180%, respectively) compared with the contralateral intact pads, but did not affect fat cell size (FCS). The denervation-induced increased FCN in SDs occurred despite naturally occurring decreased food intake. SDs decreased IWAT FCS regardless of the surgical treatment. These results support an important role of WAT SNS innervation in the control of FCN in vivo.

White adipose tissue sensory nerve denervation mimics lipectomy-induced compensatory increases in adiposity

2005 ◽  
Vol 289 (2) ◽  
pp. R514-R520 ◽  
Author(s):  
Haifei Shi ◽  
Timothy J. Bartness
Keyword(s):  
Adipose Tissue ◽  
Body Fat ◽  
White Adipose Tissue ◽  
Sensory Nerve ◽  
Sensory Innervation ◽  
Siberian Hamsters ◽  
Total Body Fat ◽  
Total Body ◽  
Lipid Stores ◽  
The Brain

The sensory innervation of white adipose tissue (WAT) is indicated by the labeling of sensory bipolar neurons in the dorsal root ganglion after retrograde dye placement into WAT. In addition, immunoreactivity (ir) for sensory-associated neuropeptides such as calcitonin gene-related peptide (CGRP) and substance P in WAT pads also supports the notion of WAT sensory innervation. The function of this sensory innervation is unknown but could involve conveying the degree of adiposity to the brain. In tests of total body fat regulation, partial surgical lipectomy triggers compensatory increases in the mass of nonexcised WAT, ultimately resulting in restoration of total body fat levels in Siberian hamsters and other animals. The signal that triggers this compensation is unknown but could involve disruption of WAT sensory innervation that accompanies lipectomy. Therefore, a local and selective sensory denervation was accomplished by microinjecting the sensory nerve neurotoxin capsaicin bilaterally into epididymal WAT (EWAT) of Siberian hamsters, whereas controls received vehicle injections. Additional hamsters had bilateral EWAT lipectomy (EWATx) or sham lipectomy. As seen previously, EWATx resulted in significantly increased retroperitoneal WAT (RWAT) and inguinal WAT (IWAT) masses. Capsaicin treatment significantly decreased CGRP- but not tyrosine hydroxylase-ir, attesting to the diminished and selective sensory innervation. Capsaicin-treated hamsters also had increased RWAT and, to a lesser degree, IWAT mass largely mimicking the WAT mass increases seen after lipectomy. Collectively, these data suggest the possibility that information related to peripheral lipid stores may be conveyed to the brain via the sensory innervation of WAT.

Brown and white adipose tissue metabolism in cold-exposed rats

1964 ◽  
Vol 207 (4) ◽  
pp. 840-844 ◽  
Author(s):  
G. Steiner ◽  
G. F. Cahill
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
White Adipose Tissue ◽  
Neutral Lipids ◽  
Adipose Tissue Metabolism ◽  
Epididymal Fat ◽  
Brown Adipose ◽  
Fat Pads

Brown and white adipose tissue from rats exposed to 5 C for 9 days has been studied with reference to its composition and handling of glucose-U-C14 in vivo and in vitro. Brown adipose tissue from cold-exposed rats demonstrated a decreased lipid content per milligram nitrogen, due mainly to decreased amounts of neutral lipid with little change in phospholipid. The incorporation of glucose into neutral lipids, glyceride glycerol, and fatty acids was increased in vivo and in vitro. There was increased incorporation into CO2 in vitro and there was no change in glucose conversion to phospholipid in vivo. No changes in any of these were noted in epididymal fat pads. These findings suggest that cold exposure leads to alterations in carbohydrate metabolism and lipogenesis in brown adipose tissue but not in epididymal fat pads. The possible role in thermogenesis is discussed.

Photoperiod-dependent fat pad mass and cellularity changes after partial lipectomy in Siberian hamsters

1996 ◽  
Vol 270 (2) ◽  
pp. R383-R392 ◽  
Author(s):  
M. M. Mauer ◽  
T. J. Bartness
Keyword(s):  
Adipose Tissue ◽  
Body Fat ◽  
White Adipose Tissue ◽  
Present Experiment ◽  
Inhibitory Effect ◽  
Adipocyte Size ◽  
Fat Pad ◽  
Siberian Hamsters ◽  
Long Day ◽  
Short Days

Long day (LD)-housed Siberian hamsters show compensatory mass increases in nonexcised white adipose tissue (WAT) after partial lipectomy, whereas hamsters exposed to short days (SDs) for 22 wk do not. The purpose of this experiment was to determine the cellularity changes underlying lipectomy-induced WAT compensation and whether the duration of SD exposure affects this compensation. Male Siberian hamsters were epididymal (E) or inguinal (I) WAT lipectomized (x) or sham-lipectomized (Sham) and either remained in LDs or were transferred to SDs and killed 6 or 12 wk later. In LDs, lipectomized hamsters showed compensatory mass increases in retroperitoneal WAT (RWAT) due to hyperplasia. IWAT mass also was increased by approximately 40% in LD-housed EWATx hamsters because of nonsignificant increases in adipocyte size and number at weeks 6 and 12, respectively. SD-housed hamsters responded to lipectomy by delaying the SD-associated body fat loss so that RWAT mass was reduced only one-third as much in lipectomized as in Sham hamsters, and the IWAT adipocytes of EWATx hamsters were larger than in Sham hamsters at week 6. At week 12, there was little indication of fat pad compensation by SD-housed hamsters. Collectively, the results of the present experiment and our previous study (16) suggest that the inhibitory effect of SDs on fat pad compensation after lipectomy increases with prolonged SD exposure.

A central role for hepatocyte growth factor in adipose tissue angiogenesis

2008 ◽  
Vol 294 (2) ◽  
pp. E336-E344 ◽  
Author(s):  
Lauren N. Bell ◽  
Liying Cai ◽  
Brian H. Johnstone ◽  
Dmitry O. Traktuev ◽  
Keith L. March ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Cell Migration ◽  
Endothelial Cell ◽  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Fat Pad ◽  
Hepatocyte Growth ◽  
Fat Pads

Hepatocyte growth factor (HGF) is a potent mitogenic and angiogenic factor produced in human adipose tissue. In this study, we use 3T3-F442A preadipocytes to study the contribution of HGF to angiogenesis in an in vivo fat pad development model. As observed for human adipocytes, HGF is synthesized and secreted by 3T3-F442A preadipocytes and mature adipocytes. HGF knockdown with small-interfering RNA reduced HGF mRNA expression 82.3 ± 4.2% and protein secretion 82.9 ± 1.4% from 3T3-F442A preadipocytes. Silencing of HGF resulted in a 70.5 ± 19.0% reduction in endothelial progenitor cell migration to 3T3-F442A-conditioned medium in vitro. 3T3-F442A preadipocytes injected under the skin of mice form a fat pad containing mature, lipid-filled adipocytes and a functional vasculature. At 72 h postinjection, expression of the endothelial cell genes TIE-1 and platelet endothelial cell adhesion molecule (PECAM)-1 was decreased 94.4 ± 2.2 and 91.5 ± 2.5%, respectively, in 3T3-F442A fat pads with HGF silencing. Knockdown of HGF had no effect on differentiation of 3T3-F442A preadipocytes to mature adipocytes in vitro or in vivo. In developing fat pads under the skin of HGF overexpressing transgenic mice, TIE-1 and PECAM-1 mRNA was increased 16.5- and 21.4-fold, respectively, at 72 h postinjection. The increase in gene expression correlated with immunohistochemical evidence of endothelial cell migration in the developing fat pad. These data suggest that HGF has a central role in regulating angiogenesis in adipose tissue.

scholarly journals In Vivo Response to α1-Adrenoreceptor Stimulation in Human White Adipose Tissue

2002 ◽  
Vol 10 (6) ◽  
pp. 555-558 ◽  
Author(s):  
Michael Boschmann ◽  
Götz Krupp ◽  
Friedrich C. Luft ◽  
Susanne Klaus ◽  
Jens Jordan
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue

scholarly journals Effects of PKB/Akt inhibitors on insulin-stimulated lipogenesis and phosphorylation state of lipogenic enzymes in white adipose tissue

2020 ◽  
Vol 477 (8) ◽  
pp. 1373-1389
Author(s):  
Nusrat Hussain ◽  
Sheng-Ju Chuang ◽  
Manuel Johanns ◽  
Didier Vertommen ◽  
Gregory R. Steinberg ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Acute Effects ◽  
Lipogenic Enzymes ◽  
Atp Citrate Lyase ◽  
Phosphorylation State ◽  
Epididymal Fat ◽  
Citrate Lyase ◽  
Fat Pads

We investigated acute effects of two allosteric protein kinase B (PKB) inhibitors, MK-2206 and Akti-1/2, on insulin-stimulated lipogenesis in rat epididymal adipocytes incubated with fructose as carbohydrate substrate. In parallel, the phosphorylation state of lipogenic enzymes in adipocytes and incubated epididymal fat pads was monitored by immunoblotting. Preincubation of rat epididymal adipocytes with PKB inhibitors dose-dependently inhibited the following: insulin-stimulated lipogenesis, increased PKB Ser473 phosphorylation, increased PKB activity and decreased acetyl-CoA carboxylase (ACC) Ser79 phosphorylation. In contrast, the effect of insulin to decrease the phosphorylation of pyruvate dehydrogenase (PDH) at Ser293 and Ser300 was not abolished by PKB inhibition. Insulin treatment also induced ATP-citrate lyase (ACL) Ser454 phosphorylation, but this effect was less sensitive to PKB inhibitors than ACC dephosphorylation by insulin. In incubated rat epididymal fat pads, Akti-1/2 treatment reversed insulin-induced ACC dephosphorylation, while ACL phosphorylation by insulin was maintained. ACL and ACC purified from white adipose tissue were poor substrates for PKBα in vitro. However, effects of wortmannin and torin, along with Akti-1/2 and MK-2206, on recognized PKB target phosphorylation by insulin were similar to their effects on insulin-induced ACL phosphorylation, suggesting that PKB could be the physiological kinase for ACL phosphorylation by insulin. In incubated epididymal fat pads from wild-type versus ACC1/2 S79A/S212A knockin mice, effects of insulin to increase lipogenesis from radioactive fructose or from radioactive acetate were reduced but not abolished. Together, the results support a key role for PKB in mediating insulin-stimulated lipogenesis by decreasing ACC phosphorylation, but not by decreasing PDH phosphorylation.

Textural analysis differentiates brown and white adipose tissue on magnetic resonance imaging (MRI) in vivo

2018 ◽  
Vol 73 ◽  
pp. e10-e11
Author(s):  
Terence Alan Jones ◽  
Abhir Bhalero ◽  
Sarah Wayte ◽  
Thomas Barber ◽  
Charle Hutchinson
Keyword(s):  
Magnetic Resonance Imaging ◽  
Adipose Tissue ◽  
Magnetic Resonance ◽  
White Adipose Tissue ◽  
Textural Analysis ◽  
Resonance Imaging ◽  
Magnetic Resonance Imaging Mri

scholarly journals Polyinosinic: Polycytidylic Acid and Murine Cytomegalovirus Modulate Expression of Murine IL-10 and IL-21 in White Adipose Tissue

Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 569
Author(s):  
Pablo Garcia-Valtanen ◽  
Ruth Marian Guzman-Genuino ◽  
John D. Hayball ◽  
Kerrilyn R. Diener
Keyword(s):  
Adipose Tissue ◽  
B Cells ◽  
White Adipose Tissue ◽  
Ex Vivo ◽  
Interleukin 10 ◽  
Poly I:C ◽  
Murine Cytomegalovirus ◽  
Polycytidylic Acid ◽  
Polyinosinic Polycytidylic Acid

White adipose tissue (WAT) produces interleukin-10 and other immune suppressors in response to pathogen-associated molecular patterns (PAMPs). It also homes a subset of B-cells specialized in the production of IL-10, referred to as regulatory B-cells. We investigated whether viral stimuli, polyinosinic: polycytidylic acid (poly(I:C)) or whole replicative murine cytomegalovirus (MCMV), could stimulate the expression of IL-10 in murine WAT using in vivo and ex vivo approaches. Our results showed that in vivo responses to systemic administration of poly(I:C) resulted in high levels of endogenously-produced IL-10 and IL-21 in WAT. In ex vivo WAT explants, a subset of B-cells increased their endogenous IL-10 expression in response to poly(I:C). Finally, MCMV replication in WAT explants resulted in decreased IL-10 levels, opposite to the effect seen with poly(I:C). Moreover, downregulation of IL-10 correlated with relatively lower number of Bregs. To our knowledge, this is the first report of IL-10 expression by WAT and WAT-associated B-cells in response to viral stimuli.

Sign in / Sign up

Export Citation Format

Share Document