Risk factors for persistent positive anticardiolipin antibodies in women with recurrent pregnancy loss

Antiphospholipid syndrome (APS) is an established cause of recurrent pregnancy loss (RPL). It is necessary to detect persistently positive antiphospholipid antibodies to diagnose APS. This study aimed to explore risk factors for persistent anticardiolipin (aCL) positivity. Women with a history of RPL or with a history of one or more intrauterine fetal deaths after 10 weeks underwent examinations to determine the causes of RPL, including antiphospholipid antibodies. If aCL-IgG or aCL-IgM antibodies were positive, retests were performed at least 12 weeks apart. Risk factors for persistent aCL antibody positivity were retrospectively investigated. The number and percentage of cases above the 99th percentile were 74/2399 (3.1%) for aCL-IgG, and 81/2399 (3.5%) for aCL-IgM. Of the initially tested cases, 2.3% (56/2399) for aCL-IgG and 2.0% (46/2289) for aCL-IgM were ultimately positive above the 99th percentile in retests. Retest values after 12 weeks were significantly lower than the initial values for both IgG and IgM immunoglobulin classes. Initial aCL antibody titers were significantly higher in the persistent-positive group than in the transient-positive group for both IgG and IgM immunoglobulin classes. The cut-off values for predicting persistent positivity of aCL-IgG antibodies and aCL-IgM antibodies were 15 U/mL (99.1 percentile) and 11 U/mL (99.2 percentile), respectively. The only risk factor for persistently positive aCL antibodies is a high antibody titer during the initial test. When the aCL antibody titer in the initial test exceeds the cut-off value, therapeutic strategies can be defined in subsequent pregnancies without waiting for 12 weeks.

P5390Adipolin/C1q/Tnf-related protein 12 attenuates adverse cardiac remodeling in a mouse model of myocardial infarction

Background

Ischemic heart disease is one of leading causes of death worldwide. Obesity is closely linked to the development of cardiovascular diseases including ischemic heart disease. Adipose tissue produces various secretory bioactive proteins called as adipokines, and dysregulation of adipokine production contributes to the pathogenesis of obesity-related complications. Previously we identified adipolin, also referred to as C1q/Tnf-related protein12, as an insulin-sensitizing adipokine that is down-regulated in obesity. Here, we investigated the effects of adipolin on cardiac remodeling in a mouse model of myocardial infarction (MI).

Method

Male adipolin-knockout (APL-KO) and wild-type (WT) mice were subjected to the permanent ligation of the left anterior descending coronary artery to create MI. Echocardiographic and histological analyses were performed to evaluate cardiac function and myocardial remodeling at 4 weeks after MI. Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Cardiomyocyte cross sectional area was evaluated by Wheat Germ Agglutinin staining. Perivascular fibrosis was assessed by Masson's trichrome staining. Neonatal rat ventricular myocytes were used as cultured cardiac myocytes for in vitro study.

Results

APL-KO mice exhibited increased ratios of the heart weight/body weight and lung weight/body weight after MI compared with WT mice. APL-KO mice showed increased left ventricular diastolic diameter and decreased fractional shortening after MI compared with WT mice. APL-KO mice had increases in myocardial apoptosis, cardiomyocyte hypertrophy and perivascular fibrosis at the remote zone of infarct hearts as compared with WT mice. Treatment of cultured cardiomyocytes with adipolin protein reduced apoptosis in response to 24 hours of hypoxia. Treatment with adipolin protein also increased the phosphorylation of Akt in cardiomyocytes. Inhibition of PI3 kinase/Akt signaling by LY294002 reversed the anti-apoptotic effects of adipolin in cultured cardiomyocytes.

Conclusion

Our data indicate that adipolin prevents pathological myocardial remodeling after chronic ischemia, at least in part, by suppressing myocardial apoptosis through an Akt-dependent mechanism.

1440Anti-inflammatory adipokine, omentin, attenuates angiotensin II-induced abdominal aortic aneurysm formation in apolipoprotein-E knockout mice

Background

Abdominal aortic aneurysm (AAA) is an increasing and life-threatening disease. Obesity is associated with an increased risk of AAA. Omentin is a circulating adipokine, which is downregulated by obesity. Recently we have demonstrated that omentin is an anti-inflammatory adipokine that prevents the development of atherosclerosis in apolipoprotein-E knockout (apoE-KO) mice. Here we examined whether omentin could modulate angiotensin II-induced AAA formation in apoE-KO mice.

Methods and results

To overexpress human omentin in apoE-KO mice, apoE-KO mice were crossed with transgenic mice expressing the human omentin gene in fat tissue under the control of AP2 promoter (OMT-Tg mice). Circulating levels of human omentin in apoE-KO/OMT-Tg mice were approximately threefold higher than those in healthy human subjects, whereas human omentin was undetectable in apoE-KO mice. There were no differences in body weight, blood pressure and heart rate between apoE-KO/OMT-Tg and apoE-KO mice. We also subjected apoE-KO/OMT-Tg and apoE-KO mice at 24 weeks of age to continuous angiotensin II-infusion by using osmotic mini pumps for 4 weeks, which is a widely-accepted model of experimental AAA. ApoE-KO/OMT-Tg mice exhibited a lower incidence of AAA formation and a reduced maximal diameter of AAA determined by direct measurement and ultrasound imaging as compared with apo-E KO mice. In histological analyses with van Gieson staining, apoE-KO/OMT-Tg mice showed attenuated disruption of medial elastic fibers in response to angiotensin II compared with apo-E KO mice. ApoE-KO/OMT-Tg mice also displayed reduced mRNA levels of matrix metalloproteinase (MMP) 2 and MMP9 as well as pro-inflammation genes including interleukin (IL)-6 in aortic walls compared with apo-E KO mice. Treatment of human monocyte-derived macrophages with human omentin protein attenuated LPS-stimulated expression of MMP9, TNF-α and IL-6. Omentin treatment also reduced LPS-induced activation of MMP9 in cultured media of human macrophages as evaluated by gelatinolytic zymography. Omentin treatment increased phosphorylation levels of Akt in human macrophages. The suppressive effects of omentin on inflammatory response in macrophages were reversed by treatment with LY294002, which is an inhibitor of PI3 kinase/Akt signaling.

Conclusion

These data suggest that omentin acts as an adipokine that can attenuate angiotensin II-induced development of AAA through suppression of MMP activation and inflammatory response in the vascular wall.

Gasless laparoscopically assisted myomectomy using a wound retraction system

INTRODUCTION

The purpose of this study was to elucidate the feasibility of gasless laparoscopically assisted myomectomy (LAM) using a wound retraction system. This method treats symptomatic uterine myomas by combining laparoscopy with a mini-laparotomy to enucleate myoma nodules and to close the uterine myometrium.

METHODS

This study includes 275 patients who underwent gasless LAM. For patients with fewer than three myoma nodules, the location of the largest nodule was classified as anterior, fundal, or posterior. The operative outcomes, intraoperative and postoperative courses, and complications were examined.

RESULTS

All operations were performed satisfactorily, and no conversions to laparotomy were required. None of the patients developed serious complications. The mean blood loss and operating time were 190.3 mL and 152.2 minutes, respectively. The mean myoma size was 8.9 cm, and the mean number of myomas per patient was 2.8. The average postoperative hospital stay was 5.7 days. There were no significant differences in resected myoma size, blood loss, and surgical duration with respect to the location of the largest nodule.

CONCLUSION

Gasless LAM with a wound retractor is feasible and allows surgeons to perform myomectomy safely and cost-effectively, without requiring advanced laparoscopic surgical skills and while maintaining minimum invasiveness.

Alveolar macrophage activation and an emphysema-like phenotype in adiponectin-deficient mice

Adiponectin is an adipocyte-derived collectin that acts on a wide range of tissues including liver, brain, heart, and vascular endothelium. To date, little is known about the actions of adiponectin in the lung. Herein, we demonstrate that adiponectin is present in lung lining fluid and that adiponectin deficiency leads to increases in proinflammatory mediators and an emphysema-like phenotype in the mouse lung. Alveolar macrophages from adiponectin-deficient mice spontaneously display increased production of tumor necrosis factor-alpha (TNF-alpha) and matrix metalloproteinase (MMP-12) activity. Consistent with these observations, we found that pretreatment of alveolar macrophages with adiponectin leads to TNF-alpha and MMP-12 suppression. Together, our findings show that adiponectin leads to macrophage suppression in the lung and suggest that adiponectin-deficient states may contribute to the pathogenesis of inflammatory lung conditions such as emphysema.

Novel LPL mutation (L303F) found in a patient associated with coronary artery disease and severe systemic atherosclerosis

BACKGROUND

Patients with lipoprotein lipase (LPL) deficiency had been generally thought to be spared accelerated atherosclerosis in spite of a marked elevation of plasma triglyceride levels. However, it has been recently reported that some heterozygous and homozygous LPL-deficient patients are associated with premature atherosclerosis. In this paper, we report a 55-year-old type I hyperlipidaemic patient with a novel missense mutation in the LPL gene.

PATIENT AND RESULTS

The patient had suffered from coronary artery disease, abdominal aortic aneurysm, and stenoses of the bilateral renal arteries and superficial femoral arteries. Sequencing of the genomic DNA revealed that the patient was a homozygote for the mutation, a G to C transition at nucleotide position 1069 in the exon 6, resulting in an amino acid substitution of Phe for Leu303 (L303F). Approximately 6% and approximately 40% of normal LPL activity and LPL mass, respectively, were detected in the patient's postheparin plasma. An in vitro expression study demonstrated that COS7 cells transfected with L303F mutant cDNA produced a 40% amount of LPL protein in cell lysates compared with normal cDNA, but no protein was detected in the media. Lipoprotein lipase activity was completely absent in both lysates and media of the cells transfected with the mutant cDNA, suggesting that this mutation in the LPL gene results in the production of a functionally inactive protein.

CONCLUSION

This case suggests that the LPL missense mutation (L303F), which impairs lipolysis but preserves the LPL mass, is proatherogenic.

Enhancement of the aquaporin adipose gene expression by a peroxisome proliferator-activated receptor gamma

The current study demonstrates that aquaporin adipose (AQPap), an adipose-specific glycerol channel (Kishida, K., Kuriyama, H., Funahashi, T., Shimomura, I., Kihara, S., Ouchi, N., Nishida, M., Nishizawa, H., Matsuda, M., Takahashi, M., Hotta, K., Nakamura, T., Yamashita, S., Tochino, Y., and Matsuzawa, Y. (2000) J. Biol. Chem. 275, 20896-20902), is a target gene of peroxisome proliferator-activated receptor (PPAR) gamma. The AQPap mRNA amounts increased following the induction of PPARgamma in the differentiation of 3T3-L1 adipocytes. The AQPap mRNA in the adipose tissue increased when mice were treated with pioglitazone (PGZ), a synthetic PPARgamma ligand, and decreased in PPARgamma(+/-) heterozygous knockout mice. In 3T3-L1 adipocytes, PGZ augmented the AQPap mRNA expression and its promoter activity. Serial deletion of the promoter revealed the putative peroxisome proliferator-activated receptor response element (PPRE) at -93/-77. In 3T3-L1 preadipocytes, the expression of PPARgamma by transfection and PGZ activated the luciferase activity of the promoter containing the PPRE, whereas the PPRE-deleted mutant was not affected. The gel mobility shift assay showed the direct binding of PPARgamma-retinoid X receptor alpha complex to the PPRE. DeltaPPARgamma, which we generated as the dominant negative PPARgamma lacking the activation function-2 domain, suppressed the promoter activity in 3T3-L1 cells, dose-dependently. We conclude that AQPap is a novel adipose-specific target gene of PPARgamma through the binding of PPARgamma-retinoid X receptor complex to the PPRE region in its promoter.

Genomic structure and insulin-mediated repression of the aquaporin adipose (AQPap), adipose-specific glycerol channel

Aquaporin adipose (AQPap) is a putative glycerol channel in adipocytes (Kishida, K., Kuriyama, H., Funahashi, T., Shimomura, I., Kihara, S., Ouchi, N., Nishida, M., Nishizawa, H., Matsuda, M., Takahashi, M., Hotta, K., Nakamura, T., Yamashita, S., Tochino, Y., and Matsuzawa, Y. (2000) J. Biol. Chem. 275, 20896-20902). In the current study, we examined the genomic structure of the mouse AQPap gene and its regulation by insulin. The mouse AQPap gene spanned 12 kilobase pairs in chromosome 4 and consisted of 8 exons and 7 introns. The first two exons, designated exon 1 and exon 1', are alternatively spliced to common exon 2, and thus the AQPap gene possessed two potential promoters. The exon 1-derived transcript is dominant in both adipose tissues and adipocytes on the basis of RNase protection assay and promoter analysis. The mRNA increased after fasting and decreased with refeeding. Insulin deficiency generated by streptozotocin enhanced the mRNA in adipose tissue. Insulin down-regulated AQPap mRNA in 3T3-L1 adipocytes. The AQPap promoter contained heptanucleotide sequences, TGTTTTT at -443/-437, similar to the insulin-response element identified previously in the promoters of insulin-repressed genes. Deletion and single base pair substitution analysis of the promoter revealed that these sequences were required for insulin-mediated repression of AQPap gene transcription. The phosphatidylinositol 3-kinase pathway was involved in this inhibition. We conclude that insulin represses the transcription of AQPap gene via insulin response element in its promoter. Sustained up-regulation of AQPap mRNA in adipose tissue in the insulin-resistant condition may disturb glucose homeostasis by increasing plasma glycerol.

PPARgamma ligands increase expression and plasma concentrations of adiponectin, an adipose-derived protein

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 PPARgamma 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.

The expression of SPARC in adipose tissue and its increased plasma concentration in patients with coronary artery disease

OBJECTIVE

Adipocytes secrete various cytokines and matrix proteins. Several of them precipitate in obesity-associated diseases, including atherosclerosis. In the current study, we have examined the expression of secreted protein, acidic and rich in cysteine (SPARC) in adipose tissue and its significance in obesity and coronary artery disease (CAD).

RESEARCH METHODS AND PROCEDURES

The SPARC mRNA expressions both in vivo and in vitro were detected by Northern blot analysis. Plasma SPARC concentrations were measured by enzyme immunosorbent assay. First, we investigated the plasma SPARC levels of 88 unrelated adult Japanese subjects (62 men and 26 women; average age: [+/- SD] 50 +/- 12 years; body mass index [BMI]: 16 to 46 kg/m(2)). Additionally 31 subjects with CAD diagnosed by coronary angiography (20 men and 11 women) were also investigated.

RESULTS

Human adipose tissues expressed abundant SPARC mRNA. SPARC expression in adipose tissues was upregulated in obese db/db mice. Markedly enhanced expression of SPARC mRNA was observed in 3T3-L1 fibroblasts during adipocyte differentiation. Consistent with these results, plasma SPARC levels proved a positive correlation with BMI in humans (r = 0.27; p < 0.01). Interestingly, plasma SPARC concentrations were significantly elevated in age- and BMI-matched subjects with CAD (p < 0.05).

DISCUSSION

SPARC was expressed in adipose tissues and its expression was enhanced in obese mice. In human, plasma SPARC levels were elevated in obesity and CAD patients. This elevated SPARC may be involved in the progression of CAD.

Immunohistochemical expression of gonadotropin releasing hormone receptor in human breast carcinoma

Gonadotropin releasing hormone (GnRH) analogs can cause regression of hormone-dependent breast carcinomas via the specific GnRH receptor (GnRH-R). In an attempt to obtain a better understanding of GnRH actions in human breast carcinoma, the expression of GnRH-R was examined immunohistochemically in 58 invasive ductal carcinomas and correlated with various clinicopathological parameters. GnRH-R was immunolocalized in the cytoplasm of carcinoma cells in 37 of 58 invasive ductal carcinoma cases (64%). Immunoreactivity for GnRH-R was also detected focally in the cytoplasm of morphologically normal glandular epithelia adjacent to the carcinoma. A significant correlation was observed between the immunohistochemical expression of GnRH-R and estrogen receptor labeling index (LI; P = 0.030) or progesterone receptor LI (P = 0.0074). There was a significant inverse correlation between GnRH-R immunoreactivity and Ki-67 LI (P = 0.012). No significant correlations were detected between GnRH-R and other clinicopathological parameters, including patient age, menopausal status, stage, tumor size, lymph node status, histological grade and prognosis. This study indicates that GnRH-R is widely distributed in human breast carcinoma cells and regulates GnRH actions locally. Breast carcinomas positive for GnRH-R maintain some hormonal regulatory mechanisms, and GnRH actions may lead to a low proliferative rate in human breast carcinoma.

Adipocyte-derived plasma protein, adiponectin, suppresses lipid accumulation and class A scavenger receptor expression in human monocyte-derived macrophages

BACKGROUND

Excessive lipid accumulation in macrophages plays an important role in the development of atherosclerosis. Recently, we discovered an adipocyte-specific plasma protein, adiponectin, that is decreased in patients with coronary artery disease. We previously demonstrated that adiponectin acts as a modulator for proinflammatory stimuli and inhibits monocyte adhesion to endothelial cells. The present study investigated the effects of adiponectin on lipid accumulation in human monocyte-derived macrophages.

METHODS AND RESULTS

Human monocytes were differentiated into macrophages by incubation in human type AB serum for 7 days, and the effects of adiponectin were investigated at different time intervals. Treatment with physiological concentrations of adiponectin reduced intracellular cholesteryl ester content, as determined using the enzymatic, fluorometric method. The adiponectin-treated macrophages contained fewer lipid droplets stained by oil red O. Adiponectin suppressed the expression of the class A macrophage scavenger receptor (MSR) at both mRNA and protein levels by Northern and immunoblot analyses, respectively, without affecting the expression of CD36, which was quantified by flow cytometry. Adiponectin reduced the class A MSR promoter activity, as measured by luciferase reporter assay. Adiponectin treatment dose-dependently decreased class A MSR ligand binding and uptake activities. The mRNA level of lipoprotein lipase as a marker of macrophage differentiation was decreased by adiponectin treatment, but that of apolipoprotein E was not altered. Adiponectin was detected around macrophages in the human injured aorta by immunohistochemistry.

CONCLUSIONS

The adipocyte-derived plasma protein adiponectin suppressed macrophage-to-foam cell transformation, suggesting that adiponectin may act as a modulator for macrophage-to-foam cell transformation.

Adiponectin, an adipocyte-derived plasma protein, inhibits endothelial NF-kappaB signaling through a cAMP-dependent pathway

BACKGROUND

Among the many adipocyte-derived endocrine factors, we found an adipocyte-derived plasma protein, adiponectin, that was decreased in obesity. We recently demonstrated that adiponectin inhibited tumor necrosis factor-alpha (TNF-alpha)-induced expression of endothelial adhesion molecules and that plasma adiponectin level was reduced in patients with coronary artery disease (CIRCULATION: 1999;100:2473-2476). However, the intracellular signal by which adiponectin suppressed adhesion molecule expression was not elucidated. The present study investigated the mechanism of modulation for endothelial function by adiponectin.

METHODS AND RESULTS

The interaction between adiponectin and human aortic endothelial cells (HAECs) was estimated by cell ELISA using biotinylated adiponectin. HAECs were preincubated for 18 hours with 50 microg/mL of adiponectin, then exposed to TNF-alpha (10 U/mL) or vehicle for the times indicated. NF-kappaB-DNA binding activity was determined by electrophoretic mobility shift assays. TNF-alpha-inducible phosphorylation signals were detected by immunoblotting. Adiponectin specifically bound to HAECs in a saturable manner and inhibited TNF-alpha-induced mRNA expression of monocyte adhesion molecules without affecting the interaction between TNF-alpha and its receptors. Adiponectin suppressed TNF-alpha-induced IkappaB-alpha phosphorylation and subsequent NF-kappaB activation without affecting other TNF-alpha-mediated phosphorylation signals, including Jun N-terminal kinase, p38 kinase, and Akt kinase. This inhibitory effect of adiponectin is accompanied by cAMP accumulation and is blocked by either adenylate cyclase inhibitor or protein kinase A (PKA) inhibitor.

CONCLUSIONS

These observations raise the possibility that adiponectin, which is naturally present in the blood stream, modulates the inflammatory response of endothelial cells through cross talk between cAMP-PKA and NF-kappaB signaling pathways.

Adiponectin, a new member of the family of soluble defense collagens, negatively regulates the growth of myelomonocytic progenitors and the functions of macrophages

We investigated the functions of adiponectin, an adipocyte-specific secretory protein and a new member of the family of soluble defense collagens, in hematopoiesis and immune responses. Adiponectin suppressed colony formation from colony-forming units (CFU)-granulocyte-macrophage, CFU-macrophage, and CFU-granulocyte, whereas it had no effect on that of burst-forming units-erythroid or mixed erythroid-myeloid CFU. In addition, adiponectin inhibited proliferation of 4 of 9 myeloid cell lines but did not suppress proliferation of erythroid or lymphoid cell lines except for one cell line. These results suggest that adiponectin predominantly inhibits proliferation of myelomonocytic lineage cells. At least one mechanism of the growth inhibition is induction of apoptosis because treatment of acute myelomonocytic leukemia lines with adiponectin induced the appearance of subdiploid peaks and oligonucleosomal DNA fragmentation. Aside from inhibiting growth of myelomonocytic progenitors, adiponectin suppressed mature macrophage functions. Treatment of cultured macrophages with adiponectin significantly inhibited their phagocytic activity and their lipopolysaccharide-induced production of tumor necrosis factor alpha. Suppression of phagocytosis by adiponectin is mediated by one of the complement C1q receptors, C1qRp, because this function was completely abrogated by the addition of an anti-C1qRp monoclonal antibody. These observations suggest that adiponectin is an important negative regulator in hematopoiesis and immune systems and raise the possibility that it may be involved in ending inflammatory responses through its inhibitory functions. (Blood. 2000;96:1723-1732)

Aquaporin adipose, a putative glycerol channel in adipocytes

Adipose tissue is a major site of glycerol production in response to energy balance. However, molecular basis of glycerol release from adipocytes has not yet been elucidated. We recently cloned a novel member of the aquaporin family, aquaporin adipose (AQPap), which has glycerol permeability. The current study was designed to examine the hypothesis that AQPap serves as a glycerol channel in adipocytes. Adipose tissue expressed AQPap mRNA in high abundance, but not the mRNAs for the other aquaglyceroporins, AQP3 and AQP9, indicating that AQPap is the only known aquaglyceroporin expressed in adipose tissue. Glycerol release from 3T3-L1 cells was increased during differentiation in parallel with AQPap mRNA levels and suppressed by mercury ion, which inhibits the function of AQPs, supporting AQPap functions as a glycerol channel in adipocytes. Fasting increased and refeeding suppressed adipose AQPap mRNA levels in accordance with plasma glycerol levels and oppositely to plasma insulin levels in mice. Insulin dose-dependently suppressed AQPap mRNA expression in 3T3-L1 cells. AQPap mRNA levels and adipose glycerol concentrations measured by the microdialysis technique were increased in obese mice with insulin resistance. Accordingly, negative regulation of AQPap expression by insulin was impaired in the insulin-resistant state. Exposure of epinephrine translocated AQPap protein from perinuclear cytoplasm to the plasma membrane in 3T3-L1 adipocytes. These results strongly suggest that AQPap plays an important role in glycerol release from adipocytes.

Plasma concentrations of a novel, adipose-specific protein, adiponectin, in type 2 diabetic patients

Adiponectin is a novel, adipose-specific protein abundantly present in the circulation, and it has antiatherogenic properties. We analyzed the plasma adiponectin concentrations in age- and body mass index (BMI)-matched nondiabetic and type 2 diabetic subjects with and without coronary artery disease (CAD). Plasma levels of adiponectin in the diabetic subjects without CAD were lower than those in nondiabetic subjects (6.6+/-0.4 versus 7.9+/-0.5 microg/mL in men, 7.6+/-0.7 versus 11.7+/-1.0 microg/mL in women; P<0.001). The plasma adiponectin concentrations of diabetic patients with CAD were lower than those of diabetic patients without CAD (4.0+/-0.4 versus 6.6+/-0.4 microg/mL, P<0.001 in men; 6.3+/-0.8 versus 7.6+/-0. 7 microg/mL in women). In contrast, plasma levels of leptin did not differ between diabetic patients with and without CAD. The presence of microangiopathy did not affect the plasma adiponectin levels in diabetic patients. Significant, univariate, inverse correlations were observed between adiponectin levels and fasting plasma insulin (r=-0.18, P<0.01) and glucose (r=-0.26, P<0.001) levels. In multivariate analysis, plasma insulin did not independently affect the plasma adiponectin levels. BMI, serum triglyceride concentration, and the presence of diabetes or CAD remained significantly related to plasma adiponectin concentrations. Weight reduction significantly elevated plasma adiponectin levels in the diabetic subjects as well as the nondiabetic subjects. These results suggest that the decreased plasma adiponectin concentrations in diabetes may be an indicator of macroangiopathy.

Localization of CD9, an enhancer protein for proheparin-binding epidermal growth factor-like growth factor, in human atherosclerotic plaques: possible involvement of juxtacrine growth mechanism on smooth muscle cell proliferation

Heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF), a member of the EGF family, has a potent mitogenic activity for vascular smooth muscle cells (SMCs). We previously reported that HB-EGF is involved in atherogenesis of human aorta and coronary arteries. ProHB-EGF (the membrane-anchored form of HB-EGF) has also been demonstrated to possess a mitogenic activity, which is approximately 30-fold increased when coexpressed with CD9 in mouse L cells. Thus, in the process of atherogenesis, CD9 may be involved in the proliferation of SMCs. We immunohistochemically investigated the localization of CD9 and proHB-EGF in the human aorta and coronary arteries. In normal aorta and coronary arteries, CD9 immunostaining was virtually negative, whereas proHB-EGF immunostaining was positive, especially in the arteries of babies. In contrast, in atherosclerotic lesions, some intimal SMCs were strongly positive for CD9 and proHB-EGF immunostaining. The juxtacrine growth activities of human aortic SMCs were inhibited in vitro by adding neutralization antibodies for CD9 or adding the specific inhibitor of HB-EGF. Besides, coexpressed CD9 and proHB-EGF cells markedly incorporated [(3)H]thymidine into the SMCs. CD9 is localized immunohistochemically in the SMCs of the atherosclerotic aorta and coronary arteries. CD9, when coexpressed with proHB-EGF, enhances proHB-EGF activities for SMC growth in a so-called juxtacrine manner in vitro and may be involved in atherogenesis.

An adipocyte-derived plasma protein, adiponectin, adheres to injured vascular walls

Adipose tissue secretes a variety of proteins into the bloodstream. We have previously reported a novel cDNA, apM1 (adipose most abundant gene transcript 1), which is specifically and abundantly expressed in adipose tissue [1]. Primary structure analysis predicted that the apM1 gene product possesses significant homology to collagens VIII, X and complement factor C1q, and we named it adiponectin. In the current study, we analyzed characteristics of adiponectin in vitro and in vivo. Adiponectin protein was proved to be secreted into the medium when the cDNA was transfected to COS cells. Anti-adiponectin cross-reactivities were abundantly detected in the human plasma. In solid-phase binding assays, adiponectin specifically bound to collagen types I, III and V, which are present in vascular intima. Immunohistochemical analysis revealed that adiponectin was detected in the walls of the catheter-injured vessels but not in the intact vascular walls. These data suggest that adiponectin is a plasma protein produced by adipose tissue and accumulates in vascular walls when the endothelial barrier is injured.

Novel modulator for endothelial adhesion molecules: adipocyte-derived plasma protein adiponectin

BACKGROUND

Among the many adipocyte-derived endocrine factors, we recently found an adipocyte-specific secretory protein, adiponectin, which was decreased in obesity. Although obesity is associated with increased cardiovascular mortality and morbidity, the molecular basis for the link between obesity and vascular disease has not been fully clarified. The present study investigated whether adiponectin could modulate endothelial function and relate to coronary disease.

METHODS AND RESULTS

For the in vitro study, human aortic endothelial cells (HAECs) were preincubated for 18 hours with the indicated amount of adiponectin, then exposed to tumor necrosis factor-alpha (TNF-alpha) (10 U/mL) or vehicle for the times indicated. The adhesion of human monocytic cell line THP-1 cells to HAECs was determined by adhesion assay. The surface expression of vascular cell adhesion molecule-1 (VCAM-1), endothelial-leukocyte adhesion molecule-1 (E-selectin), and intracellular adhesion molecule-1 (ICAM-1) was measured by cell ELISA. Physiological concentrations of adiponectin dose-dependently inhibited TNF-alpha-induced THP-1 adhesion and expression of VCAM-1, E-selectin, and ICAM-1 on HAECs. For the in vivo study, the concentrations of adiponectin in human plasma were determined by a sandwich ELISA system that we recently developed. Plasma adiponectin concentrations were significantly lower in patients with coronary artery disease than those in age- and body mass index-adjusted control subjects.

CONCLUSIONS

These observations suggest that adiponectin modulates endothelial inflammatory response and that the measurement of plasma adiponectin levels may be helpful in assessment of CAD risk.

Paradoxical decrease of an adipose-specific protein, adiponectin, in obesity

We isolated the human adipose-specific and most abundant gene transcript, apM1 (Maeda, K., et al., Biochem. Biophys. Res. Commun. 221, 286-289, 1996). The apM1 gene product was a kind of soluble matrix protein, which we named adiponectin. To quantitate the plasma adiponectin concentration, we have produced monoclonal and polyclonal antibodies for human adiponectin and developed an enzyme-linked immunosorbent assay (ELISA) system. Adiponectin was abundantly present in the plasma of healthy volunteers in the range from 1.9 to 17.0 mg/ml. Plasma concentrations of adiponectin in obese subjects were significantly lower than those in non-obese subjects, although adiponectin is secreted only from adipose tissue. The ELISA system developed in this study will be useful for elucidating the physiological and pathophysiological role of adiponectin in humans.

Troglitazone suppresses intimal formation following balloon injury in insulin-resistant Zucker fatty rats

Troglitazone, a thiazolidinedione derivative, overcomes insulin resistance through promoting insulin receptor function. However, the effect of the resultant enhancement of insulin action on the regulation of cellular proliferation remains unknown. We investigated the effect of troglitazone on intimal proliferation after balloon injury in insulin-resistant Zucker fatty rats. Troglitazone markedly decreased blood glucose and triglyceride levels at the therapeutic dosage. The area of neointima significantly decreased in treated animals 2 weeks after operation, as compared with the untreated control animals (0.0526 +/- 0.0292 and 0.115 +/- 0.0354 mm2, respectively). The ratio of neointimal to medial area in treated rats (0.75 +/- 0.26) decreased by as much as 53% compared with untreated rats (1.40 +/- 0.05). We next examined DNA synthesis in cultured smooth muscle cells (SMCs) derived from non-insulin-resistant rats, to assess whether troglitazone suppresses the proliferation of vascular SMCs independent of metabolic effects. The result showed that troglitazone decreased [methyl-3H]thymidine incorporation into DNA. In conclusion, treatment with troglitazone in Zucker fatty rats resulted in a reduction in neointima formation after balloon injury, and also corrected hypertriglyceridemia and hyperglycemia. In addition, in vitro studies revealed that the anti-proliferative effect of troglitazone stems from its direct action on DNA synthesis rather than any accompanying metabolic changes. Therefore, troglitazone seems to be applicable in preventing atherosclerosis in patients with insulin resistance.

Troglitazone enhances glucose uptake and inhibits mitogen-activated protein kinase in human aortic smooth muscle cells

The thiazolidinedione analogue troglitazone is an antidiabetic agent that improves insulin resistance in rodents and humans. Although coronary artery disease is common in patients with the insulin resistance syndrome, the effects of troglitazone on smooth muscle cells (SMC) have not been fully elucidated. We therefore examined the effects of troglitazone on cell growth and glucose uptake in human aortic SMC. Mitogen-activated protein (MAP) kinase activity and glucose transporter (Glut) 1 mRNA levels were also studied. In the absence of troglitazone, insulin (10(-7) M) caused a 2-fold increase of DNA synthesis in SMC and troglitazone suppressed the increase of DNA synthesis in a dose-dependent manner. This growth suppression was accompanied by inhibition of MAP kinase activity. On the other hand, troglitazone significantly increased Glut 1 mRNA and enhanced glucose uptake in SMC. These results suggest that troglitazone affects the insulin signaling pathways in SMC and suppresses growth while promoting glucose uptake. Our findings support the application of troglitazone as an inhibitor of SMC proliferation in patients with insulin resistance.

Role of membrane-anchored heparin-binding epidermal growth factor-like growth factor and CD9 on macrophages

Heparin-binding epidermal-growth-factor-like growth factor (HB-EGF) is a potent mitogen for smooth-muscle cells (SMCs) belonging to the EGF family. We have previously determined that HB-EGF is expressed in macrophages and SMCs of human atherosclerotic lesions and that its membrane-anchored precursor, proHB-EGF, also has a juxtacrine mitogenic activity which is markedly enhanced by CD9, a surface marker of lymphohaemopoietic cells. Therefore, when both proHB-EGF and CD9 are expressed on macrophages, they may strongly promote the development of atherosclerosis. In the present study we have investigated the changes in proHB-EGF and CD9 in THP-1 cells during differentiation into macrophages and by the addition of oxidized low-density lipoproteins (OxLDL) and assessed juxtacrine growth activity of THP-1 macrophages for human aortic SMCs. HB-EGF and CD9 at both the mRNA and the protein level were up-regulated after differentiation into macrophages, and further expression of HB-EGF was induced by the addition of OxLDL or lysophosphatidylcholine. Juxtacrine induction by formalin-fixed growth was suppressed to control levels by an inhibitor of HB-EGF and was partially decreased by anti-CD9 antibodies. These results suggest that co-expression of proHB-EGF and CD9 on macrophages plays an important role in the development of atherosclerosis by a juxtacrine mechanism.

Acetylcholine-induced coronary microvascular vasospasm in a patient with angina pectoris and normal coronary angiogram--a case report

We demonstrated a continuous intracoronary infusion of acetylcholine-induced marked decrease of coronary blood flow estimated by intracoronary Doppler flow wire without significant epicardial coronary narrowing. This case can be called a patient with microvascular vasospastic angina.

[Long-term follow-up study of transcatheter arterial chemotherapy in patients with advanced breast cancer]

Intra-arterial infusion chemotherapy (I.A) was applied to 32 cases with advanced breast cancer. The subclavian artery was intubated and one shot of 30 mg of adriamycin was given every 3 days, with a total dose of over 150 mg. Then mastectomy was performed after this chemotherapy. Long-term follow-up study revealed that the response rates of the primary tumor to I.A chemotherapy provided the prospects for their prognosis. The 3-and 5-year survival of good responders (% tumor regression greater than or equal to 70%) was significantly better than those of poor responders (% tumor regression less than 70%). Then, four patients with advanced breast cancer were treated with combination of I.A infusion chemotherapy of Adriamycin and photoradiation by argon laser. The mean interval time for 50% tumor regression was shorter than in the cases treated with Adriamycin alone. In vitro, the effects of the photoradiation for MCF-7 breast cancer cell line were observed only at a high concentration of Adriamycin.

Ecological studies of Japanese encephalitis virus in Hokkaido: interepidemic outbreaks of swine abortion and evidence for the virus to overwinter locally

Outbreaks of abortion and stillbirth caused by Japanese encephalitis virus were observed in swine populations in Hokkaido in 1984 and 1985. Two strains of Japanese encephalitis virus were isolated from aborted fetuses in different outbreaks, and the antigenic types of the strains found to be different from Nakayama and JaGAr-01. The outbreak of 1985 was in early June, the interepidemic period of Japanese encephalitis in northern temperate zones. A seroepidemiological survey carried out from 1984 to 1986 in 14 districts showed high rates of Japanese encephalitis antibody in swine sera in two districts. A more detailed 3-year survey showed that pig farms positive for Japanese encephalitis antibody were detected at the same sites in Hiroshima near Sapporo as negative farms. These data suggest that Japanese encephalitis virus is maintained in a distinct endemic focus and has the capacity to overwinter locally in Hokkaido.

The occurrence of paranuclear vacuoles in sheep ruminal epithelium treated with distilled water in vitro and from sheep injected with a large quantity of water into the rumen

In the histological preparation taken after animal death, paranuclear vacuoles (PV) in sheep ruminal epithelium were already present in high percentage (7.5-20.3%). With the incubation of the ruminal mucosae in distilled water (10-15 degrees C) up to 120 min, PV occurrence did not alter. With incubation in NaCl solution, however, PV value decreased with time proportional to NaCl concentration (0.5, 0.85 or 1.5%). In the preparation taken by biopsy, on the other hand, PV were rare in ruminal epithelium (less than 0.3%). With the injection of warm water (10-141/animal), however, PV occurrence in the ruminal epithelium was not affected. PV as cytoplasmic processes of the ruminal Langerhans cells are probably formed by the reaction of these cells to environmental changes in the tissue caused by animal death.