Adipokine Gene Expression in Dog Adipose Tissues and Dog White Adipocytes Differentiated in Primary Culture

Abstract

Obesity and its associated disorders are increasing in companion animals, particularly in dogs. We have investigated whether genes encoding key adipokines, some of which are implicated in the pathologies linked to obesity, are expressed in canine adipose tissues. Using RT-PCR, mRNAs encoding the following adipokines were detected in dog white adipose tissue: adiponectin, leptin, angiotensinogen, plasminogen activator inhibitor-1, IL-6, haptoglobin, metallothionein-1 and 2, and nerve growth factor. The adipokine mRNAs were present in all fat depots examined. Fractionation of adipose tissue by collagenase digestion showed that each gene was expressed in mature adipocytes. The mRNA for TNFα was not evident in adipose tissue, but was detected in isolated adipocytes. Fibroblastic preadipocytes from gonadal white fat were differentiated into adipocytes in primary culture and adipokine expression examined before and after differentiation (days 0 and 11, respectively). Each adipokine gene expressed in dog white adipocytes was also expressed in the differentiated cells. These results demonstrate that dog white adipose tissue expresses major adipokine genes, expression being in the adipocytes. Investigation of adipokine production and function will provide insight into the mechanisms involved in obesity-related pathologies in dogs and serve as a model for the related human diseases.

Key words

Adiponectin - Cell culture - Cytokines - Leptin - TNFα - White adipose tissue

References

• 1 Trayhurn P, Beattie J H. Physiological role of adipose tissue: white adipose tissue as an endocrine and secretory organ.  Proc Nutr Soc. 2001;  60 329-339
• 2 Frühbeck G, Gómez-Ambrosi J, Muruzabal F J, Burrell M A. The adipocyte: a model for integration of endocrine and metabolic signaling in energy metabolism regulation.  Am J Physiol Endocrinol Metab. 2001;  280 E827-E847
• 3 Rajala M W, Scherer P E. Minireview: The adipocyte - at the crossroads of energy homeostasis, inflammation, and atherosclerosis.  Endocrinology. 2003;  144 3765-3773
• 4 Zhang Y Y, Proenca R, Maffei M, Barone M, Leopold L, Friedman J M. Positional cloning of the mouse obese gene and its human homolog.  Nature. 1994;  372 425-432
• 5 Harris R B. Leptin - much more than a satiety signal.  Annu Rev Nutr. 2000;  20 45-75
• 6 Trayhurn P, Wood I S. Adipokines: Inflammation and the pleiotropic role of white adipose tissue.  Br J Nutr. 2004;  92 347-355
• 7 Considine R V, Sinha M K, Heiman M L, Kriauciunas A, Stephens T W, Nyce M R, Ohannesian J P, Marco C C, McKee L J, Bauer T L, Caro J F. Serum immunoreactive leptin concentrations in normal-weight and obese humans.  New Engl J Med. 1996;  334 292-295
• 8 Ostlund R E, Yang J W, Klein S, Gingerich R. Relation between plasma leptin concentration and body fat, gender, diet, age, and metabolic covariates.  J Clin Endocrinol Metab. 1996;  81 3909-3913
• 9 Alessi M C, Bastelica D, Morange P, Berthet B, Leduc I, Verdier M, Geel O, Juhan-Vague I. Plasminogen activator inhibitor 1, transforming growth factor-β(1), and BMI are closely associated in human adipose tissue during morbid obesity.  Diabetes. 2000;  49 1374-1380
• 10 Bastard J P, Jardel C, Bruckert E, Blondy P, Capeau J, Laville M, Vidal H, Hainque B. Elevated levels of interleukin 6 are reduced in serum and subcutaneous adipose tissue of obese women after weight loss.  J Clin Endocrinol Metab. 2000;  85 3338-3342
• 11 Mutch N J, Wilson H M, Booth N A. Plasminogen activator inhibitor-1 and haemostasis in obesity.  Proc Nutr Soc. 2001;  60 341-347
• 12 Hotamisligil G S. Inflammatory pathways and insulin action.  Int J Obesity. 2003;  27 Suppl 3 S53-S55
• 13 Hauner H. Regulation of human adipocyte expression of secreted peptides. In: Medeiros-Neto G, Halpern A, Bouchard C (eds) Progress in Obesity Research: 9. London; John Libbey 2003: 1984-1988
• 14 Chiellini C, Santini F, Marsili A, Berti P, Bertacca A, Pelosini C, Scartabelli G, Pardini E, Lopez-Soriano J, Centoni R, Ciccarone A M, Benzi L, Vitti P, Del Prato S, Pinchera A, Maffei M. Serum haptoglobin: a novel marker of adiposity in humans.  J Clin Endocrinol Metab. 2004;  89 2678-2683
• 15 Arita Y, Kihara S, Ouchi N, Takahashi M, Maeda K, Miyagawa J, Hotta K, Shimomura I, Nakamura T, Miyaoka K, Kuriyama H, Nishida M, Yamashita S, Okubo K, Matsubara K, Muraguchi M, Ohmoto Y, Funahashi T, Matsuzawa Y. Paradoxical decrease of an adipose-specific protein, adiponectin, in obesity.  Biochem Biophys Res Commun. 1999;  257 79-83
• 16 Hotta K, Funahashi T, Arita Y, Takahashi M, Matsuda M, Okamoto Y, Iwahashi H, Kuriyama H, Ouchi N, Maeda K, Nishida M, Kihara S, Sakai N, Nakajima T, Hasegawa K, Muraguchi M, Ohmoto Y, Nakamura T, Yamashita S, Hanafusa T, Matsuzawa Y. Plasma concentrations of a novel, adipose-specific protein, adiponectin, in type 2 diabetic patients.  Arterioscl Thromb Vasc Biol. 2000;  20 1595-1599
• 17 Butterwick R F, Hawthorne A J. Advances in dietary management of obesity in dogs and cats.  J Nutr. 1998;  128 2771S-2775S
• 18 Hoenig M. Comparative aspects of diabetes mellitus in dogs and cats.  Mol Cell Endocrinol. 2002;  197 221-229
• 19 Markwell P J, Butterwick R F, Wills J M, Raiha M. Clinical studies in the management of obesity in dogs and cats.  Int J Obesity. 1994;  18 Suppl 1 S39-S43
• 20 Kirkness E F, Bafna V, Halpern A L, Levy S, Remington K, Rusch D B, Delcher A L, Pop M, Wang W, Fraser C M, Venter J C. The dog genome: survey sequencing and comparative analysis.  Science. 2003;  301 1898-1903
• 21 O’Brien S J, Murphy W J. Genomics.  A dog’s breakfast? Science. 2003;  301 1854-1855
• 22 Bergman R N, van Citters G W, Mittelman S D, Dea M K, Hamilton-Wessler M, Kim S P, Ellmerer M. Central role of the adipocyte in the metabolic syndrome.  J Invest Med. 2001;  49 119-126
• 23 Hauner H, Skurk T, Wabitsch M. Cultures of human adipose precursor cells.  Methods Mol Biol. 2001;  155 239-247
• 24 Peeraully M R, Jenkins J R, Trayhurn P. NGF gene expression and secretion in white adipose tissue: regulation in 3T3-L1 adipocytes by hormones and inflammatory cytokines.  Am J Physiol Endocrinol Metab. 2004;  287 E331-E339
• 25 Wang B, Jenkins J R, Trayhurn P. Expression and secretion of inflammation-related adipokines by human adipocytes differentiated in culture: Integrated response to TNF-α.  Am J Physiol Endocrinol Metab. 2005;  288 E731-E740
• 26 Hausman G J. The comparative anatomy of adipose tissue. In: Cryer A, Van RLR (eds) New Perspectives in Adipose Tissue: Structure, Function and Development. London; Butterworths 1985: 1-21
• 27 Wu P, Sato K, Yukawa S, Hikasa Y, Kagota K. Differentiation of stromal-vascular cells isolated from canine adipose tissues in primary culture.  J Vet Med Sci. 2001;  63 17-23
• 28 Gregoire F M, Smas C M, Sul H S. Understanding adipocyte differentiation.  Physiol Rev. 1998;  78 783-809
• 29 Scherer P E, Williams S, Fogliano M, Baldini G, Lodish H F. A novel serum protein similar to C1q, produced exclusively in adipocytes.  J Biol Chem. 1995;  270 26 746-26 749
• 30 Wolf G. Adiponectin: a regulator of energy homeostasis.  Nutr Rev. 2003;  61 290-292
• 31 Ouchi N, Kihara S, Arita Y, Maeda K, Kuriyama H, Okamoto Y, Hotta K, Nishida M, Takahashi M, Nakamura T, Yamashita S, Funahashi T, Matsuzawa Y. Novel modulator for endothelial adhesion molecules - Adipocyte-derived plasma protein adiponectin.  Circulation. 1999;  100 2473-2476
• 32 Yokota T, Oritani K, Takahashi I, Ishikawa J, Matsuyama A, Ouchi N, Kihara S, Funahashi T, Tenner A J, Tomiyama Y, Matsuzawa Y. Adiponectin, a new member of the family of soluble defense collagens, negatively regulates the growth of myelomonocytic progenitors and the functions of macrophages.  Blood. 2000;  96 1723-1732
• 33 Berg A H, Combs T P, Du X, Brownlee M, Scherer P E. The adipocyte-secreted protein Acrp30 enhances hepatic insulin action.  Nature Med. 2001;  7 947-953
• 34 Yamauchi T, Kamon J, Waki H, Terauchi Y, Kubota N, Hara K, Mori Y, Ide T, Murakami K, Tsuboyama-Kasaoka N, Ezaki O, Akanuma Y, Gavrilova O, Vinson C, Reitman M L, Kagechika H, Shudo K, Yoda M, Nakano Y, Tobe K, Nagai R, Kimura S, Tomita M, Froguel P, Kadowaki T. The fat-derived hormone adiponectin reverses insulin resistance associated with both lipoatrophy and obesity.  Nature Med. 2001;  7 941-946
• 35 Trayhurn P, Duncan J S, Wood A M, Beattie J H. Metallothionein gene expression and secretion by white adipose tissue.  Am J Physiol. 2000;  279 R2329-R2335
• 36 Do M S, Nam S Y, Hong S E, Kim K W, Duncan J S, Beattie J H, Trayhurn P. Metallothionein gene expression in human adipose tissue from lean and obese subjects.  Horm Metab Res. 2002;  34 348-351
• 37 Karlsson C, Lindell K, Ottosson M, Sjostrom L, Carlsson B, Carlsson L MS. Human adipose tissue expresses angiotensinogen and enzymes required for its conversion to angiotensin II.  J Clin Endocrinol Metab. 1998;  83 3925-3929
• 38 Oller do Nascimento C, Hunter L, Trayhurn P. Regulation of haptoglobin gene expression in 3T3-L1 adipocytes by cytokines, catecholamines, and PPARγ.  Biochem Biophys Res Commun. 2004;  313 702-708
• 39 Levi-Montalcini R, Skaper S D, Dal Toso R, Petrelli L, Leon A. Nerve growth factor: from neurotrophin to neurokine.  Trends Neurosci. 1996;  19 514-520
• 40 Vega J A, Garcia-Suarez O, Hannestad J, Perez-Perez M, Germana A. Neurotrophins and the immune system.  J Anat. 2003;  203 1-19
• 41 Hotamisligil G S, Shargill N S, Spiegelman B M. Adipose expression of tumor necrosis factor-alpha - direct role in obesity-linked insulin resistance.  Science. 1993;  259 87-91
• 42 Coppack S W. Pro-inflammatory cytokines and adipose tissue.  Proc Nutr Soc. 2001;  60 349-356
• 43 Ruan H, Zarnowski M J, Cushman S W, Lodish H F. Standard isolation of primary adipose cells from mouse epididymal fat pads induces inflammatory mediators and down-regulates adipocyte genes.  J Biol Chem. 2003;  278 47 585-47 593
• 44 Fried S K, Bunkin D A, Greenberg A S. Omental and subcutaneous adipose tissues of obese subjects release interleukin-6: depot difference and regulation by glucocorticoid.  J Clin Endocrinol Metab. 1998;  83 847-850