Diabetes
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Maeda, N.
Right arrow Articles by Matsuzawa, Y.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Maeda, N.
Right arrow Articles by Matsuzawa, Y.
Social Bookmarking
Add to CiteULike   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?
Diabetes 50:2094-2099, 2001
© 2001 by the American Diabetes Association, Inc.

PPAR{gamma} Ligands Increase Expression and Plasma Concentrations of Adiponectin, an Adipose-Derived Protein

Norikazu Maeda, Masahiko Takahashi, Tohru Funahashi, Shinji Kihara, Hitoshi Nishizawa, Ken Kishida, Hiroyuki Nagaretani, Morihiro Matsuda, Ryutaro Komuro, Noriyuki Ouchi, Hiroshi Kuriyama, Kikuko Hotta, Tadashi Nakamura, Iichiro Shimomura, and Yuji Matsuzawa

Department of Internal Medicine and Molecular Science (B5), Graduate School of Medicine, Osaka University, Osaka, Japan


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 RESEARCH DESIGN AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
Insulin resistance and its dreaded consequence, type 2 diabetes, are major causes of atherosclerosis. Adiponectin is an adipose-specific plasma protein that possesses anti-atherogenic properties, such as the suppression of adhesion molecule expression in vascular endothelial cells and cytokine production from macrophages. Plasma adiponectin concentrations are decreased in obese and type 2 diabetic subjects with insulin resistance. A regimen that normalizes or increases the plasma adiponectin might prevent atherosclerosis in patients with insulin resistance. In this study, we demonstrate the inducing effects of thiazolidinediones (TZDs), which are synthetic PPAR{gamma} ligands, on the expression and secretion of adiponectin in humans and rodents in vivo and in vitro. The administration of TZDs significantly increased the plasma adiponectin concentrations in insulin resistant humans and rodents without affecting their body weight. Adiponectin mRNA expression was normalized or increased by TZDs in the adipose tissues of obese mice. In cultured 3T3-L1 adipocytes, TZD derivatives enhanced the mRNA expression and secretion of adiponectin in a dose- and time-dependent manner. Furthermore, these effects were mediated through the activation of the promoter by the TZDs. On the other hand, TNF-{alpha}, which is produced more in an insulin-resistant condition, dose-dependently reduced the expression of adiponectin in adipocytes by suppressing its promoter activity. TZDs restored this inhibitory effect by TNF-{alpha}. TZDs might prevent atherosclerotic vascular disease in insulin-resistant patients by inducing the production of adiponectin through direct effect on its promoter and antagonizing the effect of TNF-{alpha} on the adiponectin promoter.


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
RESEARCH DESIGN AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
Insulin resistance is characterized by a reduced sensitivity of insulin to target tissues. The insulin-resistant state is a common basis for hypertension and coronary artery disease, as well as type 2 diabetes (1). Although obesity is a common cause of insulin resistance, the molecular link between increased adiposity and human diseases remains unclear (2). Adipose tissue synthesizes and secretes biologically active molecules that might be called "adipocytokines" (3,4,5). Dysregulation of adipocytokines in obesity might play a role in the development of insulin resistance and vascular disorders. A cytokine, tumor necrosis factor-{alpha} (TNF-{alpha}), is overproduced by adipose tissue in obese mice and causes systemic insulin resistance by interfering with the insulin-signaling cascade (6,7). Leptin, a central regulator of adiposity, also affects glucose homeostasis (8,9). More recently, resistin, which is a novel adipose-specific cysteine-rich protein, has been found to impair insulin sensitivity and glucose tolerance (10). TNF-{alpha} enhances the cell surface expression of adhesion molecules on vascular endothelial cells (11). Thus, TNF-{alpha} may also contribute to the initial step of atherosclerosis. Furthermore, increased expression and secretion of plasminogen activator inhibitor 1 (PAI-1) and angiotensinogen in the adipose tissue may link obesity to thrombotic vascular disease and hypertension (12,13).

Adiponectin is a product of the apM1 gene, which is specifically and highly expressed in human adipose tissue (14). The protein belongs to the soluble defense collagen superfamily and is present in human plasma at a concentration of 5–30 µg/ml (15). This protein, also referred to as gelatin-binding protein 28, was independently purified from plasma using gelatin affinity chromatography (16). In mechanically injured vascular walls, adiponectin could be detected in the subendothelial space (17). A mouse homologue was identified in two independent laboratories and designated AdipoQ and ACRP30, respectively (18,19). The expression of AdipoQ and ACRP30 was limited to the adipose tissue and reduced in obesity. Plasma adiponectin concentrations and mRNA expression were decreased in obese humans, despite increased adiposity, and in patients with type 2 diabetes with insulin resistance (15,20,21).

Hyperinsulinemic-euglycemic clamp studies have revealed that the degree of hypoadiponectinemia is closely related to the degree of insulin resistance (22,23). In vitro, adiponectin attenuates the TNF-{alpha}–induced expression of adhesion molecules in vascular endothelial cells and the secretion of TNF-{alpha} from monocyte macrophages (24,25,26). These results suggest that adiponectin may work as an anti-atherogenic factor. In fact, marked decreases in the plasma adiponectin concentrations were observed in patients with coronary artery disease and macroangiopathy related to diabetes (21,24). Therefore, the high incidence of coronary artery disease in patients with insulin resistance may be partially attributed to hypoadiponectinemia, and a regimen that could increase the plasma adiponectin might prevent the development of atherosclerosis in those with insulin resistance.

The peroxisome proliferator–activated receptor (PPAR)-{gamma} is the master regulator of adipocyte differentiation and controls many adipocyte genes. Its synthetic ligands, thiazolidinediones (TZDs), are a new class of antidiabetic drugs that improve insulin action. In the current study, we show that TZDs can markedly enhance the expression and secretion of adiponectin in vitro and in vivo through the activation of its promoter, and that these compounds also antagonize the suppressive effect of TNF-{alpha} on the production of adiponectin. Through the induction of adiponectin, TZDs might prevent atherosclerosis in diabetic patients with insulin resistance.


   RESEARCH DESIGN AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 RESEARCH DESIGN AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
Effect of troglitazone on plasma adiponectin concentration in humans.
A total of 29 subjects (16 men, 13 women, average age 50 ± 3 years, BMI 29.1 ± 0.8 kg/m2) with glucose intolerance were eligible for the study and gave written informed consent. The study was performed in accordance with good clinical practice and with the approval of the respective institutional review boards and the ethical committee of Osaka University Graduate School of Medicine. The subjects were randomly allocated to either placebo or troglitazone (TGZ) 100 or 200 mg twice daily for 12 weeks. Fasting plasma glucose, immunoreactive insulin, HbA1c, and adiponectin concentrations were measured before and after treatment. The plasma adiponectin concentrations were measured by sandwich enzyme-linked immunosorbent assay as previously described (15).

Effect of TZDs on adipose expression and plasma level of adiponectin/ACRP30 in mice.
Eight-week old male C57BL/KsJ (db+/+m) (n = 20) and C57BL/KsJ (db+/db+) (n = 20) mice (Clea Japan, Tokyo) were fed powder chow (CRF-1; Oriental Kobo, Suita, Japan). The chow consisted of 53.5% (wt/wt) carbohydrate, 5.9% (wt/wt) fat, 23.1% (wt/wt) protein, and 3.3% (wt/wt) dietary fiber. At 13 weeks, the mice were divided into four groups. Each group, consisting of five db+/+m and five db+/db+ mice, was fed powder chow containing either 0.2% TGZ, 0.01% pioglitazone (PGZ), 0.5% rosiglitazone (RGZ), or no TZDs (control group), respectively. The mice were killed 2 weeks later after an overnight fast.

Total RNA extracted from subcutaneous adipose tissues was electrophoresed and transferred to nylon membranes (24). The membranes were hybridized with murine adiponectin homologue/ACRP30 or a TNF-{alpha} cDNA probe labeled with [{alpha}-32P]dCTP.

Plasma adiponectin concentrations were measured by Western blotting. An equal aliquot of plasma was resolved on a 12.5% SDS-PAGE gel, followed by electrophoretic transfer to a nitrocellulose membrane. The signal was detected using the ECL system (Amersham) with a rabbit polyclonal antibody against murine adiponectin/ACRP30 and anti-rabbit HRP antibody.

Effect of TZDs and TNF-{alpha} on the expression and secretion of adiponectin/ACRP30 in 3T3-L1 adipocytes.
Mouse 3T3-L1 cells were maintained in Dulbecco’s modified Eagle medium (DMEM) containing 10% fatal calf serum (FCS) and differentiated with DMEM supplemented with 5 µg/ml of insulin, 0.5 mmol/l 1-methyl-3-isobutyl-xanthin, and 1 µmol/l dexamethazone 2 days after reaching confluence. On day 7, the indicated concentrations of TZDs and/or murine TNF-{alpha} (Pepro Tech EC) were added to the media at the indicated concentrations for 24 h.

Adiponectin/ACRP30 mRNA levels were measured by Northern blotting. An aliquot of the media from 12 to 24 h after stimulation was subjected to Western blotting to detect the amount of adiponectin/ACRP30 that was secreted.

Effect of TZDs and TNF-{alpha} on the promoter activity of adiponectin in 3T3-L1 adipocytes.
On day 7 after differentiation, the media of the 3T3-L1 cells in 12-well plates were changed to OPTI-MEM (Life Technologies), and the cells were transfected with plasmid using Lipofectamine 2000 reagent (Life Technologies) according to the manufacturer’s instructions. Transfections were performed using 10 ng of pRL (Renilla luciferase)-SV40 (internal standard) along with pGL3-basic plasmid containing the adiponectin promoter or with pGL3-basic alone. Three hours later, an equal amount of DMEM or DMEM containing TZDs or TNF-{alpha} was added to the media. At 48 h after transfection, luciferase reporter assays were performed using the Dual-Luciferase Reporter Assay System (Promega), and the transfection efficiencies were normalized to the Renilla luciferase activity.

Statistical analysis.
The data are expressed as means ± SE. Differences were analyzed by the paired Student’s t test or one-way analysis of variance. P < 0.05 was considered statistically significant.


   RESULTS
TOP
 ABSTRACT
 INTRODUCTION
 RESEARCH DESIGN AND METHODS
 RESULTS
DISCUSSION
 REFERENCES
 
Elevation of plasma adiponectin level by TZD in humans.
We first tested the effect of insulin-sensitizing TZD on the plasma concentrations of adiponectin in humans. TGZ was the only available TZD when this study was performed. The study subjects were middle-aged, mildly overweight, and had impaired glucose tolerance. The TGZ-treated and placebo groups were well matched for BMI, body fat composition, and fasting plasma glucose. No subjects had any subjective side effects or persistent abnormalities in their laboratory variables. The administration of TGZ for 12 weeks did not change the BMIs significantly. As shown in Fig. 1, the subjects in the placebo group did not show any significant change in their plasma adiponectin concentration (2.6 ± 0.2 vs. 2.7 ± 0.2 µg/ml). However, the administration of 200 mg of TGZ per day for 12 weeks significantly increased the plasma adiponectin concentration (3.3 ± 0.6 vs. 5.9 ± 1.4 µg/ml, P < 0.01). Furthermore, a marked increase in the plasma adiponectin was detected in the subjects treated with TGZ 400 mg/day (3.0 ± 0.3 vs. 8.8 ± 2.0 µg/ml, P < 0.001).



View larger version (14K):
[in this window]
[in a new window]
  		FIG. 1. Effect of TGZ on plasma adiponectin level in humans. Effects of TGZ on human plasma adiponectin levels were studied in 29 mildly overweight subjects with glucose intolerance. The subjects were divided randomly into three groups: placebo group (n = 8), TGZ 200 mg/day group (n = 10), and TGZ 400 mg/day group (n = 11). Each group was treated with the indicated amount of TGZ for 12 weeks. Data are represented as percentage change relative to the mean levels before the treatment. Values are means ± SE.

 
Augmentation of adipose expression and plasma concentration of adiponectin by TZDs in mice.
To further elucidate the effect of TZDs on adiponectin in vivo, we treated lean and obese (db/db) mice with various TZDs for 2 weeks and measured the plasma adiponectin and the mRNA levels in white adipose tissue (Figs. 2A and B). In the chow-treated control group, the plasma concentration and mRNA levels of adiponectin were significantly lower than in the obese mice, as previously described (18). Treatment with TGZ, PGZ, or RGZ increased the plasma adiponectin and mRNA levels in both lean and obese mice. These treatments caused the reduced plasma adiponectin and mRNA levels to return to normal in obese mice and to normal or higher than normal levels in the chow-treated lean mice. Because ectopic expression of adiponectin mRNA was not observed in other tissues with these treatments (such as the liver and kidney), the increased plasma adiponectin caused by TZDs is most likely attributable to increased production in adipose tissues (data not shown). TNF-{alpha} was shown to increase with obesity and was considered as one of the key molecules for insulin resistance (6,7). TNF-{alpha} mRNA levels were elevated in the adipose tissue of obese mice, and the elevated TNF-{alpha} mRNA was decreased in the adipose tissue by the treatment of these compounds, consistent with previous reports (7,27) (Fig. 2C).



View larger version (19K):
[in this window]
[in a new window]
  		FIG. 2. Effect of TZDs on plasma levels and adipose expression of adiponectin in mice. Effect of TZDs on plasma concentrations (A), mRNA levels of adiponectin (B), or TNF-{alpha} (C) in lean and obese mice were investigated. Male 13-week-old lean and db/db mice were divided into four groups: control, TGZ, PGZ, and RGZ groups. After 2 weeks of the treatment of 0.2% (wt/wt) TGZ, 0.01% PGZ, or 0.5% RGZ, plasma and subcutaneous fat RNA samples were prepared and analyzed. Values are means ± SE. *P < 0.05, **P < 0.01 compared with control chow-treated lean or obese group, respectively. ¶P < 0.05 compared with lean control group.

 
Inducible effects of TZDs on the expression and secretion of adiponectin in 3T3-L1 adipocytes.
We investigated the effect of TZDs on the regulation of adiponectin gene expression in 3T3-L1 adipocytes. Incubation with TGZ enhanced adiponectin mRNA expression and adiponectin secretion into the media in a dose-dependent fashion (Figs. 3A and B). The induction of adiponectin mRNA expression by TGZ was detected after 3 h and reached a maximum after 12 h of treatment (Fig. 3C). Two other TZDs (PGZ and RGZ) also had a similar inducing effect on adiponectin mRNA expression, although Wy14643, a synthetic PPAR{alpha} ligand, had no significant effect (Fig. 3D). We next studied the effects of PPAR{gamma} activators on the -2.0- kb human adiponectin promoter activity (28). TGZ, PGZ, and RGZ enhanced the adiponectin promoter activity by 4.7-, 6.6-, and 10.0-fold, respectively, although Wy14,643 had no effect (Fig. 3E). These results suggest that the in vivo induction of adiponectin expression by TZDs is most likely secondary to the direct activation of the adiponectin promoter.



View larger version (23K):
[in this window]
[in a new window]
  		FIG. 3. Effects of TZDs on expression and secretion of adiponectin in 3T3-L1 adipocytes. Dose effect of TGZ on the adionectin mRNA level (A) and the secreted amount in media (B) is shown. After differentiation-induction on day 7, 3T3-L1 cells were treated with the indicated concentrations of TGZ, 0, 1, 3, and 10 µmol/l for 24 h. Five micrograms of total RNA was subjected to Northern blotting and quantified and normalized relative to the 18-s rRNA signal. All mRNAs are plotted as percentage change relative to mRNA level by 0 µmol/l TGZ treatment. The amount of adiponectin secreted into media was measured by quantitative Western blotting. The inset shows a representative picture of Northern and Western blotting that was quantified. Time curve of the effect of 10 µmol/l TGZ on adiponectin mRNA (C) is shown. After differentiation-induction on day 7, 3T3-L1 cells were treated with 10 µmol/l TGZ for the indicated time. Northern blotting and quantification was performed as described in the legend of A. After differentiation-induction on day 7, 3T3-L1 cells were treated with 10 µmol/l TGZ, PGZ, RGZ, and Wy14643, respectively (D). Northern blotting and quantification was performed as described for A. A 2.0-kb adiponectin promoter was subcloned into pGL3-luciferase vector (E). Adiponectin-luciferase and pRL-SV40 vector were cotransfected into day 7–differentiated 3T3-L1 cells. For each 12-well dish, 1 µg adiponectin-luciferase and 10 ng pRL-SV40 were used. Three hours after transfection, the cells were switched to medium containing vehicle (DMSO), or 10 µmol/l TGZ (T), PGZ (P), RGZ (R), or Wy14643 (W) for 24 h. Firefly and Renilla luciferase reporter activity was measured as described in RESEARCH DESIGN AND METHODS. Adiponectin-luciferase (firefly) activities were normalized by pRL-SV40 Renilla luciferase activity. Values are means ± SE from three independent exeriments. *P < 0.01 compared with control values.

 
Suppressive effects of TNF{alpha} on the expression and secretion of adiponectin in 3T3-L1 adipocytes.
TNF-{alpha} has been shown to increase in obesity and is considered one of the key molecules involved in insulin resistance (6,7). TNF-{alpha} dose-dependently reduced the expression and the secretion of adiponectin in 3T3-L1 adipocytes (Figs. 4A and B). The reducing effect of TNF-{alpha} on adiponectin mRNA was antagonized by coincubation with TGZ (Fig. 4C). This result was confirmed in an analysis of adiponectin promoter activity. Incubation with 0.1 ng/ml TNF-{alpha} decreased promoter activity by 80%. When these cells were coincubated with TGZ, the promoter activity returned to basal level (Fig. 4D).



View larger version (30K):
[in this window]
[in a new window]
  		FIG. 4. Effect of TNF-{alpha} on expression and secretion of adiponectin in 3T3-L1 adipocytes. Dose effect of TNF-{alpha} on the adionectin mRNA level (A) and the secreted amount in media (B) are shown. After differentiation-induction on day 7, 3T3-L1 cells were treated with indicated concentrations of TNF-{alpha} for 24 h. One nanogram per milliliter of TNF-{alpha} corresponds to 57 pmol/l. Total RNAs (5 µg) were subjected to Northern blotting and quantified as described in the legend of Fig. 3A. The amount of adiponectin secreted into media was measured by quantitative Western blotting. Inset shows a representative picture of Northern and Western blotting that was quantified. After differentiation-induction on day 7, 3T3-L1 cells were treated with or without 1 ng/ml TNF-{alpha} and 10 µmol/l TGZ for 24 h (C). Total RNAs (5 µg) were subjected to Northern blotting and quantified as described in the legend of Fig. 3A. Effects of TNF-{alpha} on the adiponectin promoter activity were analyzed as described in Fig. 3E (D). Adiponectin-luciferase and pRL-SV40 vector were cotransfected into day 7–differentiated 3T3-L1 cells. For each 12-well dish, 1 µg adiponectin-luciferase and 10 ng pRL-SV40 were used. Three hours after transfection, an equal amount of DMSO or DMEM containing TZDs or TNF-{alpha} was supplemented to medium. At 48 h after transfection, cells were harvested, and firefly and Renilla luciferase reporter activity was measured as described in RESEARCH DESIGN AND METHODS. Adiponectin-luciferase (firefly) activity was normalized by pRL-SV40 Renilla luciferase activity. Values are means ± SE from three independent experiments. *P < 0.01 compared with control values.

 

   DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 RESEARCH DESIGN AND METHODS
 RESULTS
 DISCUSSION
REFERENCES
 
Adiponectin, an adipocyte-derived factor, possesses anti-atherogenic properties and is decreased in patients with insulin resistance (15,21,22,23,24,25,26). In the current study, we demonstrated that TZD derivatives increased the plasma adiponectin concentrations in humans and rodents through the activation of its promoter.

During the early phase of atherosclerosis, circulating monocytes attach to injured endothelial cells through adhesion molecules and invade the subintimal space (23,29). The monocytes transform into macrophages and secrete various cytokines and growth factors that promote smooth muscle cell proliferation. Adiponectin inhibits the expression of adhesion molecules and prevents the attachment of monocytes in TNF-{alpha}–stimulated human aortic endothelial cells (24,25). This protein also dramatically suppresses the secretion of TNF-{alpha} from macrophages and foam cell formation (26,30). These data suggest that adiponectin works as an anti-atherogenic molecule. Although its receptor has not been identified, adiponectin modulates NF{kappa}B signaling, at least partly, through a cAMP-dependent pathway (25). The plasma adiponectin concentration is decreased in insulin-resistant states, such as obesity and type 2 diabetes (15,21). Recently, Kissebah et al. (31) demonstrated two quantitative trait loci that influence the phenotypes of the insulin resistance–metabolic syndrome. One is located on chromosome 3q27, where the adiponectin gene is encoded (28). In light of these data, hypoadiponectinemia may play a role in the development of atherosclerotic vascular disease in patients with insulin resistance. The mechanisms that control the plasma adiponectin concentration have not been elucidated.

Many adipose-specific genes are regulated by adiposity. Previously, we have shown that weight reduction therapy increased the plasma adiponectin concentration by 40–60% (21). In this report, TZD derivatives enhanced the expression of adiponectin mRNA in adipose cells and dramatically increased the plasma adiponectin concentration. TZDs are specific ligands for PPAR{gamma}, which is a key transcriptional factor that induces adipocyte differentiation by activating the expression of adipocyte-specific genes and which is also known as an insulin sensitizer in vivo, presumably by increasing the number of mature adipocytes that can respond to an enhancing effect of insulin on glucose disposal (32,33,34,35). In many clinical trials, TZDs were shown to have a preventive effect against arteriosclerosis, although the net effect of PPAR{gamma} activation on atherosclerosis remains controversial (33,34,36,37,38,39). Increased adiponectin expression and increased plasma adiponectin concentrations might explain the anti-atherogenic effect of these compounds. A 2.0-kb fragment of the human adiponectin promoter had adipose-specific promoter activity and cis-elements for several adipogenic transcriptional factors, including CCAAT enhancer binding protein and sterol regulatory element binding protein (28,40). The promoter activity of adiponectin was markedly enhanced by the PPAR{gamma} ligands, TZDs, although we were unable to identify a putative PPAR{gamma}-responsive element in this region in the same case of leptin (41). Thus, TZDs might activate the adiponectin promoter by a pathway other than its direct action on PPAR{gamma}. However, we observed that cotransfection of a dominant-negative form of PPAR{gamma} diminished the action of TZDs on adiponectin promoter (data not shown). TZDs therefore may enhance adiponectin promoter activity through an unidentified element responsive to PPAR{gamma}. Detailed promoter analyses need to be performed.

The mechanism responsible for the decreased adiponectin concentration in insulin resistance has been obscure. TNF-{alpha} is one of the candidate molecules responsible for causing insulin resistance (6,7). Here we demonstrated that the expression and secretion of adiponectin from adipocytes were significantly reduced by TNF-{alpha} in a dose- and time-dependent manner via its promoter activity. The expression of adiponectin mRNA was reduced in the adipose tissue of insulin-resistant obese humans and rodents, where TNF-{alpha} production was increased (18,20). Therefore, increased TNF-{alpha} might be partially responsible for the decreased adiponectin production in obesity. The current study also showed that the suppressive effect of TNF-{alpha} on adiponectin could be antagonized by TZDs in tissue culture through its direct action on the adiponectin promoter. Hence, the ability of TZDs to enhance adiponectin mRNA expression might be attributable to both the direct activation of the promoter and an inhibitory effect on the TNF-{alpha}–mediated suppression of adiponectin mRNA expression. This was reflected in the in vivo study, where TZDs normalized or even increased the adiponectin levels in both adipose tissue and the plasma in insulin-resistant obese animals and normalized the elevated adipose TNF-{alpha} mRNA levels. Conversely, we demonstrated in our previous studies that adiponectin inhibited the TNF-{alpha} signaling pathway in endothelial cells and reduced TNF-{alpha} production in macrophages (24,25,26,30). Crystal structure analysis revealed topologic homology among the mouse adiponectin homologue, ACRP30, and TNF-{alpha}, which have an evolutionary link (42). Taking all of this into account, a tempting hypothesis is that adiponectin and TNF-{alpha} may antagonize each other or perform opposite functions locally in adipose tissue and/or remotely in the arterial wall. This hypothesis is reinforced by the recent work by Fruebis et al. (43), who found that the administration of the globular domain of ACRP30 increased free fatty acid oxidation and decreased plasma glucose in mice, reflecting an improvement in insulin resistance. Further studies of in vivo models with overexpressed or disrupted adiponectin gene will be necessary to clarify the role of this molecule on the pathophysiology of insulin resistance.


   ACKNOWLEDGMENTS
 
This work was supported in part by the "Research for the Future" program from The Japan Society for the Promotion of Science (JSPS-RFTF97L00801) and Grants-in-Aid from the Ministry of Education, Science, Sports, and Culture of Japan (12307022, 12557090, 12671084). We are indebted to Eiji Kawakatsu, Akinori Nishiwaki, Shuji Handa, and Koichiro Yamaguchi (Sankyo) for their help with the study. We are also indebted to Dr. Hiroyuki Odaka (Takeda Chem.) for providing us with pioglitazone. We also thank Yuko Matsukawa and Sachiyo Tanaka for technical assistance.


   FOOTNOTES
 
Address correspondence and reprint requests to Tohru Funahashi, Department of Internal Medicine and Molecular Science, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, 565-0871, Osaka, Japan. E-mail: tohru{at}imed2.med.osaka-u.ac.jp.

Received for publication 27 March 2001 and accepted in revised form 15 June 2001.

DMEM, Dulbecco’s modified Eagle medium; FCS, fatal calf serum; PAI-1, plasminogen activator inhibitor 1; PGZ, pioglitazone; PPAR, peroxisome proliferator–activated receptor; RGZ, rosiglitazone; TGZ, troglitazone; TNF-{alpha}, tumor necrosis factor-{alpha}; TZD, thiazolidinedione.


   REFERENCES
TOP
 ABSTRACT
 INTRODUCTION
 RESEARCH DESIGN AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 

  1. Jensen NS: Obesity and cardiovascular disease: is body structure a factor? Curr Opin Lipidol 8:200–204, 1997[Medline]
  2. Kahn BB, Flier JS: Obesity and insulin resistance. J Clin Invest 106:473–481, 2000[Medline]
  3. Maeda K, Okubo K, Shimomura I, Mizuno K, Matsuzawa Y, Matsubara K: Analysis of an expression profile of genes in the human adipose tissue. Gene 190:227–235, 1997[Medline]
  4. Matsuzawa Y, Funahashi T, Nakamura T: Molecular mechanism of metabolic syndrome X: contribution of adipocytokines adipocyte-derived bioactive substances. Ann N Y Acad Sci 892:146–154, 1999[Abstract/Free Full Text]
  5. Funahashi T, Nakamura T, Shimomura I, Maeda K, Hiroshi K, Takahashi M, Arita Y, Kihara S, Matsizawa Y: Role of adipocytokines on the pathogenesis of atherosclerosis in visceral obesity. Internal Medicine 38:202–206, 1999
  6. Hotamisligil GS, Arner P, Caro JF, Atkinson RL, Spiegelman BM: Increased adipose tissue expression of tumor necrosis factor-alpha in human obesity and insulin resistance. J Clin Invest 95:2409–2415, 1995
  7. Hotamisligil GS, Shargill NS, Spiegelman BM: Adipose expression of tumor necrosis factor-alpha: direct role in obesity-linked insulin resistance. Science 259:87–91, 1993[Abstract/Free Full Text]
  8. Zhang Y, Proenca R, Maffei M, Barone M, Leopold L, Friedman JM: Positional cloning of the mouse obese gene and its human homologue. Nature 372:425–432, 1994[Medline]
  9. Shimomura I, Hammer RE, Ikemoto S, Brown MS, Goldstein JL: Leptin reverses insulin resistance and diabetes mellitus in mice with congenital lipodystrophy. Nature 401:73–76, 1999[Medline]
  10. Steppan CM: The hormone resistin links obesity to diabetes. Nature 409:307–312, 2001[Medline]
  11. Ross R: Atherosclerosis: an inflammatory disease. N Engl J Med 340:115–126, 1999[Free Full Text]
  12. Shimomura I, Funahashi T, Takahashi M, Maeda K, Kotani K, Nakamura T, Yamashita S, Miura M, Fukuda Y, Takemura K, Tokunaga K, Matsuzawa Y: Enhanced expression of PAI-1 in visceral fat: possible contributor to vascular disease in obesity. Nature Med 2:800–802, 1996[Medline]
  13. Frederich RC, Kahn BB, Peach MJ, Flier JS: Tissue-specific nutritional regulation of angiotensinogen in adipose tissue. Hypertension 19:339–344, 1992[Abstract/Free Full Text]
  14. Maeda K, Okubo K, Shimomura I, Funahashi T, Matsuzawa Y, Matsubara K: cDNA cloning and expression of a novel adipose specific collagen-like factor, apM1 (adipose most abundant gene transcript 1). Biochem Biophys Res Commun 221:286–289, 1996[Medline]
  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 257:79–83, 1999[Medline]
  16. Nakano Y, Tobe T, Choi-Miura N, Masuda T, Tomita M: Isolation and characterization of GBP28, a novel gelatin-binding protein purified from human plasma. J Biochem (Tokyo) 120:803–812, 1996[Abstract/Free Full Text]
  17. Okamoto Y, Arita Y, Nishida M, Muraguchi M, Ouchi N, Takahashi M, Igura T, Inui N, Kihara S, Nakamura T, Yamashita S, Miyagawa J, Funahashi T, Matsuzawa Y: An adipocyte-derived plasma protein, adiponectin, adheres to injured vascular walls. Horm Metab Res 32:47–50, 2000[Medline]
  18. Hu E, Liang P, Spiegelman BM: AdipoQ is a novel adipose-specific gene dysregulated in obesity. J Biol Chem 271:10697–10703, 1996[Abstract/Free Full Text]
  19. Scherer EP, Williams S, Fogliano M, Baldini G, Lodish HF: A novel serum protein similar to C1q, produced exclusively in adipocytes. J Biol Chem 270:26746–26749, 1995[Abstract/Free Full Text]
  20. Statnick MA, Beavers LS, Conner LJ, Corominola H, Johnson D, Hammond CD, Rafaeloff-Phail R, Seng T, Suter TM, Sluka JP, Ravussin E, Gadski RA, Caro JF: Decreased expression of apM-1 in omental and subcutaneous adipose tissue of humans with type 2 diabetes. Int J Exp Diabetes Res 1:81–88, 2000[Medline]
  21. 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. Arterioscler Thromb Vasc Biol 20:1595–1599, 2000[Abstract/Free Full Text]
  22. Weyer C, Funahashi T, Tanaka S, Hotta K, Matsuzawa Y, Pratley RE, Tatarami PA: Hypoadiponectinemia in obesity and type 2 diabetes: close association with insulin resistance and hyperinsulinemia. J Clin Endocrinol Metab 86:1930–1935, 2001[Abstract/Free Full Text]
  23. Hotta K, Funahashi T, Bodkin NL, Ortmeyer HK, Arita Y, Hansen BC, Matsuzawa Y: Circulating concentrations of the adipocyte protein adiponectin are decreased in parallel with reduced insulin sensitivity during the progression to type 2 diabetes in rhesus monkeys. Diabetes 50:1126–1133, 2001[Abstract/Free Full Text]
  24. 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 100:2473–2476, 1999[Abstract/Free Full Text]
  25. Ouchi N, Kihara S, Arita Y, Okamoto Y, Maeda K, Kuriyama H, Hotta K, Nishida M, Takahashi M, Muraguchi M, Ohmoto Y, Nakamura T, Yamashita S, Funahashi T, Matsuzawa Y: Adiponectin, adipocyte-derived plasma protein, inhibits endothelial NF-{kappa}B signaling through cAMP-dependent pathway. Circulation 102:1296–1301, 2000[Abstract/Free Full Text]
  26. Ouchi N, Kihara S, Arita Y, Nishida M, Matsuyama A, Okamoto Y, Ishigami M, Kuriyama H, Kishida K, Nishizawa H, Hotta K, Muraguchi M, Ohmoto Y, Yamashita S, Funahashi T, Matsuzawa Y: Adipocyte-derived plasma protein, adiponectin, suppresses lipid accumulation and class A scavenger receptor expression in human monocyte-derived macrophages. Circulation 103:1057–1063, 2001[Abstract/Free Full Text]
  27. Hofmann C, Lorenz K, Braithwaite SS, Colca JR, Palazuk BJ, Hotamisligil GS, Spiegelman BM: Altered gene expression for tumor necrosis factor-alpha and its receptors during drug and dietary modulation of insulin resistance. Endocrinology 134:264–270, 1994[Abstract]
  28. Takahashi M, Arita Y, Yamagata K, Matsukawa Y, Okutomi K, Horie M, Shimomura I, Hotta K, Kuriyama H, Kihara S, Nakamura T, Yamashita S, Funahashi T, Matsuzawa Y: Genomic structure and mutations in adipose-specific gene, adiponectin. Int J Obes 24:861–868, 2000[Medline]
  29. Ross R: The pathogenesis of atherosclerosis: a perspective for the 1990s. Nature 362:801–809, 1993[Medline]
  30. Yokota T, Oritani K, Takahashi I, Ishikawa J, Matsuyama A, Ouchi N, Kihara S, Funahashi T, Tenner AJ, Tomiyama Y, Matsuzawa Y: Adiponectin, a novel member of soluble defense collagens, negatively regulates the growth of myelo-monocytic progenitors and the functions of macrophages. Blood 96:1723–1732, 2000[Abstract/Free Full Text]
  31. Kissebah AH, Sonnenberg GE, Myklebust J, Goldstein M, Broman K, James RG, Marks JA, Krakower GR, Jacob HJ, Weber J, Martin L, Blangero J, Comuzzie AG: Quantitative trait loci on chromosomes 3 and 17 influence phenotypes of the metabolic syndrome. Proc Natl Acad Sci U S A 97:14478–14483, 2000[Abstract/Free Full Text]
  32. Okuno A, Tamemoto H, Tobe K, Ueki K, Mori Y, Iwamoto K, Umesono K, Akanuma Y, Fujiwara T, Horikoshi H, Yazaki Y, Kadowaki T: Troglitazone increases the number of small adipocytes without the change of white adipose tissue mass in obese Zucker rats. J Clin Invest 101:1354–1361, 1998[Medline]
  33. Olefsky JM: Treatment of insulin resistance with peroxisome proliferator-activated receptor gamma agonists. J Clin Invest 106:467–472, 2000[Medline]
  34. Rocchi S, Auwerx J: Peroxisome proliferator-activated receptor-gamma: a versatile metabolic regulator. Ann Med 31:342–351, 1999[Medline]
  35. Lin W-S, Chang H-M, Tai T-Y, Chuang L-M: Effect of thiazolidinedione on gene expression in NIH3T3–L1 adipocytes (Abstract). Diabetes 48: (Suppl. 1):A217, 1999
  36. Tontonoz P, Nagy L, Alvarez JG, Thomazy VA, Evans RM: PPAR{gamma} promotes monocyte/macrophage differentiation and uptake of oxidized LDL. Cell 93:241–252, 1998[Medline]
  37. Huang JT, Welch JS, Ricote M, Binder CJ, Willson TM, Kelly C, Witztum JL, Funk CD, Conrad D, Glass CK: Interleukin-4-dependent production of PPAR-gamma ligands in macrophages by 12/15-lipoxygenase. Nature 400:378–382, 1999[Medline]
  38. Jiang C, Ting T, Seed B: PPAR-gamma agonists inhibit production of monocyte inflammatory cytokines. Nature 391:82–86, 1998[Medline]
  39. Nagy L, Tontonoz P, Alvarez JG, Chen H, Evans RM: Oxidized LDL regulates macrophage gene expression through ligand activation of PPARgamma. Cell 93:229–240, 1998[Medline]
  40. Schaffler A, Langmann T, Palitzsch K-D, Scholmerich J, Schmitz G: Identification and characterization of the human adipocyte apM-1 promoter. Biochi Biophys Acta 1399:187–197, 1998[Medline]
  41. De Vos P, Lefebvre AM, Miller SG, Guerre-Millo M, Wong K, Saladin R, Hamann LG, Staels B, Briggs MR, Auwerx J: Thiazolidinediones repress ob gene expression in rodents via activation of peroxisome proliferator-activated receptor gamma. J Clin Invest 98:1004–1009, 1996[Medline]
  42. Shapiro L, Scherer PE: The crystal structure of a complement-1q family protein suggests an evolutionary link to tumor necrosis factor. Curr Biol 8:335–338, 1998[Medline]
  43. Fruebis J, Tsao TS, Javorschi S, Ebbets-Reed D, Erickson MR, Yen FT, Bihain BE, Lodish HF: Proteolytic cleavage product of 30-kDa adipocyte complement-related protein increases fatty acid oxidation in muscle and causes weight loss in mice. Proc Natl Acad Sci U S A 98:2005–2010, 2001[Abstract/Free Full Text]

Add to CiteULike CiteULike   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:


Home page
 Arterioscler. Thromb. Vasc. Bio.Home page
P. F. Bodary
Links Between Adipose Tissue and Thrombosis in the Mouse
Arterioscler. Thromb. Vasc. Biol., November 1, 2007; 27(11): 2284 - 2291.
[Abstract] [Full Text] [PDF]

Home page
 J EndocrinolHome page
G. Liu, M. Grifman, J. Macdonald, P. Moller, F. Wong-Staal, and Q.-X. Li
Isoginkgetin enhances adiponectin secretion from differentiated adiposarcoma cells via a novel pathway involving AMP-activated protein kinase
J. Endocrinol., September 1, 2007; 194(3): 569 - 578.
[Abstract] [Full Text] [PDF]

Home page
 Arterioscler. Thromb. Vasc. Bio.Home page
M. Itoh, T. Suganami, N. Satoh, K. Tanimoto-Koyama, X. Yuan, M. Tanaka, H. Kawano, T. Yano, S. Aoe, M. Takeya, et al.
Increased Adiponectin Secretion by Highly Purified Eicosapentaenoic Acid in Rodent Models of Obesity and Human Obese Subjects
Arterioscler. Thromb. Vasc. Biol., September 1, 2007; 27(9): 1918 - 1925.
[Abstract] [Full Text] [PDF]

Home page
 J EndocrinolHome page
G. Yuan, X. Chen, Q. Ma, J. Qiao, R. Li, X. Li, S. Li, J. Tang, L. Zhou, H. Song, et al.
C-reactive protein inhibits adiponectin gene expression and secretion in 3T3-L1 adipocytes
J. Endocrinol., August 1, 2007; 194(2): 275 - 281.
[Abstract] [Full Text] [PDF]

Home page
 Endocr. Rev.Home page
R. Muniyappa, M. Montagnani, K. K. Koh, and M. J. Quon
Cardiovascular Actions of Insulin
Endocr. Rev., August 1, 2007; 28(5): 463 - 491.
[Abstract] [Full Text] [PDF]

Home page
 Circ. Res.Home page
H. Katagiri, T. Yamada, and Y. Oka
Adiposity and Cardiovascular Disorders: Disturbance of the Regulatory System Consisting of Humoral and Neuronal Signals
Circ. Res., July 6, 2007; 101(1): 27 - 39.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
J. Lo, L. E. Bernstein, B. Canavan, M. Torriani, M. B. Jackson, R. S. Ahima, and S. K. Grinspoon
Effects of TNF-{alpha} neutralization on adipocytokines and skeletal muscle adiposity in the metabolic syndrome
Am J Physiol Endocrinol Metab, July 1, 2007; 293(1): E102 - E109.
[Abstract] [Full Text] [PDF]

Home page
 StrokeHome page
J. F. Arenillas, M. A. Moro, and A. Davalos
The Metabolic Syndrome and Stroke: Potential Treatment Approaches
Stroke, July 1, 2007; 38(7): 2196 - 2203.
[Full Text] [PDF]

Home page
 Endocr. Rev.Home page
B. L. Wajchenberg
{beta}-Cell Failure in Diabetes and Preservation by Clinical Treatment
Endocr. Rev., April 1, 2007; 28(2): 187 - 218.
[Abstract] [Full Text] [PDF]

Home page
 DiabetesHome page
E. Chevillotte, M. Giralt, B. Miroux, D. Ricquier, and F. Villarroya
Uncoupling Protein-2 Controls Adiponectin Gene Expression in Adipose Tissue Through the Modulation of Reactive Oxygen Species Production
Diabetes, April 1, 2007; 56(4): 1042 - 1050.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
S. Y. Cho, P. J. Park, H. J. Shin, Y.-K. Kim, D. W. Shin, E. S. Shin, H. H. Lee, B. G. Lee, J.-H. Baik, and T. R. Lee
(-)-Catechin suppresses expression of Kruppel-like factor 7 and increases expression and secretion of adiponectin protein in 3T3-L1 cells
Am J Physiol Endocrinol Metab, April 1, 2007; 292(4): E1166 - E1172.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
S. Nakano, Y. Inada, H. Masuzaki, T. Tanaka, S. Yasue, T. Ishii, N. Arai, K. Ebihara, K. Hosoda, K. Maruyama, et al.
Bezafibrate regulates the expression and enzyme activity of 11beta-hydroxysteroid dehydrogenase type 1 in murine adipose tissue and 3T3-L1 adipocytes
Am J Physiol Endocrinol Metab, April 1, 2007; 292(4): E1213 - E1222.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
P. E. Szmitko, H. Teoh, D. J. Stewart, and S. Verma
Adiponectin and cardiovascular disease: state of the art?
Am J Physiol Heart Circ Physiol, April 1, 2007; 292(4): H1655 - H1663.
[Abstract] [Full Text] [PDF]

Home page
 J EndocrinolHome page
Y. Kikuchi, M. Yamada, T. Imakiire, T. Kushiyama, K. Higashi, N. Hyodo, K. Yamamoto, T. Oda, S. Suzuki, and S. Miura
A Rho-kinase inhibitor, fasudil, prevents development of diabetes and nephropathy in insulin-resistant diabetic rats
J. Endocrinol., March 1, 2007; 192(3): 595 - 603.
[Abstract] [Full Text] [PDF]

Home page
 DiabetesHome page
Y. Kanatani, I. Usui, K. Ishizuka, A. Bukhari, S. Fujisaka, M. Urakaze, T. Haruta, T. Kishimoto, T. Naka, and M. Kobayashi
Effects of Pioglitazone on Suppressor of Cytokine Signaling 3 Expression: Potential Mechanisms for Its Effects on Insulin Sensitivity and Adiponectin Expression
Diabetes, March 1, 2007; 56(3): 795 - 803.
[Abstract] [Full Text] [PDF]

Home page
 Arterioscler. Thromb. Vasc. Bio.Home page
A. Hiuge, A. Tenenbaum, N. Maeda, M. Benderly, M. Kumada, E. Z. Fisman, D. Tanne, Z. Matas, T. Hibuse, K. Fujita, et al.
Effects of Peroxisome Proliferator-Activated Receptor Ligands, Bezafibrate and Fenofibrate, on Adiponectin Level
Arterioscler. Thromb. Vasc. Biol., March 1, 2007; 27(3): 635 - 641.
[Abstract] [Full Text] [PDF]

Home page
 J Am Coll CardiolHome page
S. H. Han, M. J. Quon, J.-a Kim, and K. K. Koh
Adiponectin and Cardiovascular Disease: Response to Therapeutic Interventions
J. Am. Coll. Cardiol., February 6, 2007; 49(5): 531 - 538.
[Abstract] [Full Text] [PDF]

Home page
 Eur J EndocrinolHome page
A Majuri, M Santaniemi, K Rautio, A Kunnari, J Vartiainen, A Ruokonen, Y A Kesaniemi, J S Tapanainen, O Ukkola, and L Morin-Papunen
Rosiglitazone treatment increases plasma levels of adiponectin and decreases levels of resistin in overweight women with PCOS: a randomized placebo-controlled study
Eur. J. Endocrinol., February 1, 2007; 156(2): 263 - 269.
[Abstract] [Full Text] [PDF]

Home page
 Exp. Biol. Med.Home page
R. R. Kraemer and V. D. Castracane
Exercise and Humoral Mediators of Peripheral Energy Balance: Ghrelin and Adiponectin
Experimental Biology and Medicine, February 1, 2007; 232(2): 184 - 194.
[Abstract] [Full Text] [PDF]

Home page