Combined lipid goal attainment in patients with type 2 diabetes and dyslipidemia: A head-to-head comparative trial of statins

BACKGROUND

This study compared the efficacy of two statin treatments (simvastatin vs rosuvastatin) in achieving the combined goal of low-density lipoprotein cholesterol (LDL-C) <2.6 mmol/L and non-high-density lipoprotein cholesterol (non-HDL-C) <3.4 mmol/L in patients with type 2 diabetes and dyslipidemia.

METHODS

After a 5-week run-in, 89 patients with type 2 diabetes having fasting triglyceride (TG) levels of 1.7 to 5.7 mmol/L or non-HDL-C levels of 3.4 to 5.2 mmol/L were randomized to receive simvastatin 20 mg daily for 4 weeks followed by 40 mg for 8 weeks or rosuvastatin 10 mg for 4 weeks followed by 20 mg for 8 weeks. The primary end-point was the percentage of patients achieving the combined goal at week 12.

RESULTS

Although significant between-group differences were observed in changes in LDL-C and non-HDL-C levels, both study treatments were sufficiently intensive for a 40% to 55% LDL-C reduction. At the end of the study, the two groups had similar percentages of patients who achieved the combined lipid goal (84% vs 89%, p = 0.66). All patients who attained the combined lipid goal also met the apolipoprotein B (Apo-B) target of <0.9 g/L. No between-group differences were noted in changes in HDL-C and TG levels at week 12. The patients tolerated both treatments well.

CONCLUSION

In our study, ≈85% of patients with type 2 diabetes and dyslipidemia could achieve the combined lipid goal with statin monotherapy. The two statin treatments could sufficiently control diabetic dyslipidemia (NCT00506961).

Endothelin-1 induces lipolysis through activation of the GC/cGMP/Ca2+/ERK/CaMKIII pathway in 3T3-L1 adipocytes

Endothelin-1 (ET-1) is a potent vasoconstrictive peptide produced and secreted mainly by endothelial cells. Recent studies indicate that ET-1 can regulate lipid metabolism, which may increase the risk of insulin resistance. Our previous studies revealed that ET-1 induced lipolysis in adipocytes, but the underlying mechanisms were unclear. 3T3-L1 adipocytes were used to investigate the effect of ET-1 on lipolysis and the underlying mechanisms. Glycerol levels in the incubation medium and hormone-sensitive lipase (HSL) phosphorylation were used as indices for lipolysis. ET-1 significantly increased HSL phosphorylation and lipolysis, which were completely inhibited by ERK inhibitor (PD98059) and guanylyl cyclase (GC) inhibitor (LY83583). LY83583 reduced ET-1-induced ERK phosphorylation. A Ca²⁺-free medium and PLC inhibitor caused significant decreases in ET-1-induced lipolysis as well as ERK and HSL phosphorylation, and IP₃ receptor activator (D-IP₃) increased lipolysis. ET-1 increased cGMP production, which was not affected by depletion of extracellular Ca²⁺. On the other hand, LY83583 diminished the ET-1-induced Ca²⁺ influx. Transient receptor potential vanilloid-1 (TRPV-1) antagonist and shRNA partially inhibited ET-1-induced lipolysis. ET-1-induced lipolysis was completely suppressed by CaMKIII inhibitor (NH-125). These results indicate that ET-1 stimulates extracellular Ca²⁺ entry and activates the intracellular PLC/IP₃/Ca²⁺ pathway through a cGMP-dependent pathway. The increased cytosolic Ca²⁺ that results from ET-1 treatment stimulates ERK and HSL phosphorylation, which subsequently induces lipolysis. ET-1 induces HSL phosphorylation and lipolysis via the GC/cGMP/Ca²⁺/ERK/CaMKIII signaling pathway in 3T3-L1 adipocytes.

Palmitoleic acid ameliorates palmitic acid-induced proinflammation in J774A.1 macrophages via TLR4-dependent and TNF-α-independent signallings

Adipose tissue resident macrophages play an important role in the regulation of the inflammatory response. Monounsaturated fatty acids assist in the prevention of cardiovascular diseases via an anti-inflammatory effect. However, the mechanisms by which monounsaturated fatty acids, such as palmitoleic acid, regulate the inflammatory response has not been well investigated. In this study, we found that a high concentration of palmitic acid induced J774A.1 murine macrophages toward a pro-inflammatory state, possibly through the activation of the TLR2 or TLR4 genes, and their downstream signaling pathways. In contrast, palmitoleic acid induced a protective effect against inflammation in macrophage of non-obese rodents by inducing an alternative activation pathway via reducing TLR2 or TLR4 signaling. This study indicates that the balance of palmitic acid (saturated fatty acid) and palmitoleic acid (monounsaturated fatty acid) effects macrophage activation. The potential therapeutic impact of palmitoleic acid to ameliorate non-obese-mediated inflammation warrants further investigation.

P1604Validating previously reported Brugada syndrome-associated common variants identified in caucasian population in the Han Chinese BrS cohort in Taiwan: SADS-BrS registry

Background

Brugada syndrome (BrS) is a sudden arrhythmic death. The prevalence of BrS is higher in the Southeast Asian populations than that in Caucasian patients. A previous genome-wide association study (GWAS) has reported 13 SNPs significantly associated with BrS. However, no study was performed to validate whether these SNPs are enriched in BrS patients in Han Chinese (HC).

Purpose

Evaluating the common variants previously reported in Caucasian BrS patients could be generalized to HC BrS patients in Taiwan

Methods

We genotyped 200 unrelated BrS patients using Affymetrix TWB Array (N=653,291 SNPs, a customized array for HC in Taiwan). The controls are obtained from the Taiwan Biobank (N ≈ 16,000) using the same array. An imputation workflow was shown in Figure 1. To confirm the accuracy of the imputed genotype of each variant, Sanger sequencing was performed in 10% of randomly selected cases.

Results

Among the 3 most important common variants (rs11708996 in SCN5A, rs10428132 in SCN10A and rs9388451 in HEY2/NCOA7) reported in the previous GWAS mainly conducted in Caucasian BrS patients, 2 of them (rs10428132 and rs9388451) were successfully replicated in the HC population in Taiwan (P<0.01). We also found that the differences of minor allele frequency (dMAF: the MAF of cases minus the MAF of controls) of the two variants were relatively smaller between the BrS cases and healthy controls in HC population compared with that in Caucasian populations (dMAF, rs9388451: 0.15 (Caucasian) vs −0.07 (HC); rs10428132: 0.28 (Caucasian) vs 0.11 (HC)). For the remaining 10 common variants reaching genome-wide significance (P=5×10–8) in Caucasian BrS patients, 9 of them were also significantly enriched in the HC BrS patients after the Bonferroni correction (P<0.05/12=0.0042). We next analyzed the variants identified in the previous GWAS on ECG traits (PR interval, QRS duration, QTc interval, and heart rate) in the Caucasian population. Among the reported 75 variants associated with ECG traits, 5 common variants (rs6798015 (PR), rs1760876 (QRS), rs6795970 (PR/QRS), rs2074238 (QTc) and rs314370 (heart rate)) were significant after Bonferroni correction (P<0.05/75=0.00066).

Figure 1

Conclusions

The preliminary results indicated that 85% of common variants of SCN10A and HEY2/NCOA7 previously reported in Caucasian BrS patients are replicated in BrS patients in the HC population but not the common variant of SCN5A (rs11708996). Furthermore, the common variants of SCN10A and HEY2/NCOA7 related to cardiac depolarization or repolarization may also contribute to the development of BrS.

Acknowledgement/Funding

NTUH 106-S3469, NTUH106-S3458 and NTUH 106-018

The Shipai cohort for cardiovascular metabolic risk factors and outcome study - Design and preliminary results

BACKGROUND

The aim of this study was to identify genotypic and phenotypic cardiovascular metabolic risk factors, and to establish risk models of diseases, including diabetes mellitus, cardiovascular disease, stroke, kidney dysfunction and psychiatric disorders, in Taiwanese adults.

METHODS

In 2009, a community-based cohort study was initiated in the Shipai area of the Shilin and Beitou districts in Taipei. Residents were randomly sampled by age (young adults: 35-44 years and middle-aged adults: 45-55 years) and urbanization (rural and urban). Residents who agreed to participate were scheduled to receive examinations (physical and blood) and answer questionnaires. A ten-year follow-up is anticipated. Metabolic syndrome (MetS) was defined based on the Adult Treatment Panel III guidelines, and individuals with only one or two of the five MetS components was identified for prevention target.

RESULTS

The response rate of the 9000 invited residents was 10.1%. After screening, 906 participants were enrolled. While 31.0% (281) had no MetS components, 29.1% (264) had only one, and 22.0% (199) had two. MetS with at least three components was diagnosed in 17.9% (162) of the cohort. Concerning gender difference, 25.4% of men and 13.2% of women had MetS (p < 0.001). The percentage of MetS was higher in middle-aged participants than in young adults (20.5% versus 13.4%, p = 0.008). Forty-six percent of participants had central obesity. After adjusting for gender, age, and urbanization, the central obesity odds ratio for MetS was 23.7, with a 95% confidence internal of 13.1-42.7.

CONCLUSION

Our preliminary results revealed a high MetS percentage among young and middle-aged adults in Taiwan, with central obesity being a particularly urgent prevention target. The research design and operational protocol of this cohort study may stimulate more research in the future.

Chronic endothelin-1 infusion causes adipocyte hyperplasia in rats

OBJECTIVE

The aim of this study was to investigate the regulatory mechanism of endothelin-1 (ET-1), an endothelium-derived vasoconstrictor, on adipogenesis in vitro and in vivo.

METHODS

3T3-L1 preadipocytes were used to explore the mechanisms mediating ET-1 actions on preadipocyte proliferation and adipocyte differentiation. To investigate the in vivo effect of ET-1, male Sprague-Dawley rats were infused with ET-1 or saline for 4 weeks via intraperitoneally implanted osmotic pumps, and the fat pad weight and adipocyte size of adipose tissues were measured.

RESULTS

ET-1 stimulated preadipocyte proliferation and increased the cell number at the mitotic clonal expansion stage of adipocyte differentiation via the endothelin A receptor (ETAR) and activation of the protein kinase C (PKC) pathway. ET-1, via ETAR, inhibited adipocyte differentiation partially through an ERK-dependent pathway. Furthermore, no significant difference in the body weight and fat pad weight was observed in either ET-1- or saline-infused rats. Compared with saline-infused rats, the adipocyte cell number was significantly increased but the adipocyte size was significantly decreased in ET-1-infused rats.

CONCLUSIONS

Chronic ET-1 infusion increased the number of small adipocytes without the change of white adipose tissue mass in rats, which were associated with ET-1-stimulated preadipocyte proliferation, but not ET-1-suppressed adipocyte differentiation.

Cannabinoid receptor type 1 mediates high-fat diet-induced insulin resistance by increasing forkhead box O1 activity in a mouse model of obesity

Hepatic glucose production is promoted by forkhead box O1 (FoxO1) under conditions of insulin resistance. The overactivity of cannabinoid receptor type 1 (CB1R) partly causes increased liver fat deposits and metabolic dysfunction in obese rodents by decreasing mitochondrial function. The aim of the present study was to investigate the role of FoxO1 in CB1R-mediated insulin resistance through the dysregulation of mitochondrial function in the livers of mice with high-fat diet (HFD)-induced obesity. For this purpose, male C57BL/6 mice were randomly assigned to groups and either fed a standard diet (STD), a HFD, or a HFD with 1-week treatment of the CB1R inverse agonist, AM251, at 1 or 5 mg/kg. For in vitro experiments, AML12 hepatocytes were incubated with FoxO1 siRNA prior to challenge with arachidonyl-2'-chloroethylamide (ACEA) or a high concentration of free fatty acids (HFFA). Plasma parameters were analyzed using colorimetric methods. Liver histopathology and hepatic status markers were examined. The HFD-fed mice exhibited an increase in CB1R levels in the liver. Moreover, in response to increased hepatic oxidative stress, the HFD-fed mice also displayed hepatic mitochondrial dysfunction, as indicated by the decreased mRNA levels of carnitine palmitoyltransferase-1 (CPT-1), mitochondrial transcription factor A (TFAM), nuclear respiratory factor-1 (NRF-1) and citrate synthase. On the contrary, these effects in the HFD-fed mice were reversed by treatment with 5 mg/kg AM251. The administration of AM251 suppressed the induction of FoxO1, phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6-phosphatase (G6Pase) expression in the livers of the mice fed a HFD by enhancing the phosphorylation of insulin signaling cascades thus, further lowering the high level of the homeostatic model assessment of insulin resistance (HOMA‑IR) index. In our in vitro experiments, transfection with FoxO1 siRNA prevented the HFFA- and ACEA-induced decrease in the gene expression of mitochondrial biogenesis-related factors, and abrogated the HFFA- and ACEA-induced increase in PEPCK and G6Pase expression. Taken together, our findings suggest that the anti-insulin resistance effect of AM251, which leads to an improvement of mitochondrial function in hepatic steatosis, is mediated through FoxO1.

Evidence in obese children: contribution of hyperlipidemia, obesity-inflammation, and insulin sensitivity

Background

Evidence shows a high incidence of insulin resistance, inflammation and dyslipidemia in adult obesity. The aim of this study was to assess the relevance of inflammatory markers, circulating lipids, and insulin sensitivity in overweight/obese children.

Methods

We enrolled 45 male children (aged 6 to 13 years, lean control = 16, obese = 19, overweight = 10) in this study. The plasma total cholesterol, HDL cholesterol, triglyceride, glucose and insulin levels, the circulating levels of inflammatory factors, such as TNF-α, IL-6, and MCP-1, and the high-sensitive CRP level were determined using quantitative colorimetric sandwich ELISA kits.

Results

Compared with the lean control subjects, the obese subjects had obvious insulin resistance, abnormal lipid profiles, and low-grade inflammation. The overweight subjects only exhibited significant insulin resistance and low-grade inflammation. Both TNF-α and leptin levels were higher in the overweight/obese subjects. A concurrent correlation analysis showed that body mass index (BMI) percentile and fasting insulin were positively correlated with insulin resistance, lipid profiles, and inflammatory markers but negatively correlated with adiponectin. A factor analysis identified three domains that explained 74.08% of the total variance among the obese children (factor 1: lipid, 46.05%; factor 2: obesity-inflammation, 15.38%; factor 3: insulin sensitivity domains, 12.65%).

Conclusions

Our findings suggest that lipid, obesity-inflammation, and insulin sensitivity domains predominantly exist among obese children. These factors might be applied to predict the outcomes of cardiovascular diseases in the future.

Major urinary protein 1 interacts with cannabinoid receptor type 1 in fatty acid-induced hepatic insulin resistance in a mouse hepatocyte model

Hepatic insulin resistance (HIR) is a metabolic abnormality characterized by increased gluconeogenesis which usually contributes from an elevation of free fatty acids. Cannabinoid receptor type 1 (CB1R) and major urinary protein 1 (MUP1) are thought to play pivotal roles in mitochondrial dysfunction, liver steatosis and insulin resistance. The aim of this study was to explore the role of MUP1 in CB1R-mediated HIR through the dysregulation of mitochondrial function in AML12 mouse hepatocytes challenged with high concentration of free fatty acids (HFFA). Firstly we observed that treatment of AM251, a selective CB1R antagonist, obviously reversed the HFFA-induced reduction of MUP1 protein expression both in vivo and in vitro. Additionally, our results revealed that AM251 also reverted HFFA-mediated decrease of the mRNA level of mitochondrial biogenesis-related factors, mtDNA amount, ATP production, mitochondrial respiratory complexes-I and -III, and mitochondrial membrane potential, thus consequently might correlate with a parallel reduction of ROS production. Meanwhile, AM251 attenuated HFFA-induced impairment of insulin signaling phosphorylation and elevation of phosphoenolpyrvate carboxykinase (PEPCK) and glucose 6-phosphatase (G6Pase), two key enzymes of gluconeogenesis. Silence of MUP1 gene abolished the inhibitory effect of AM251 on HFFA-mediated elevation of PEPCK and G6Pase expression, whereas the suppression of insulin signaling and mRNA level of mitochondrial biogenesis-related factors were only partially recovered. Altogether, these findings suggest that the anti-HIR effect of AM251 via improvement of mitochondrial functions might occur in a MUP1-dependent manner.

Optimal Check Size and Reversal Rate to Elicit Pattern-reversal MEG Responses

Objective:

To determine the impact of check size and interstimulus interval (ISI) on neuromagnetic visual cortical responses.

Methods:

We recorded visual evoked fields to pattern-reversal stimulation with central occlusion in ten subjects. The ~100 ms magnetic activation (P100m) was analyzed by single dipole modeling.

Results:

With 1 s ISI, P100m strengths increased as check size increased from 15' up to 120' of visual arc, and larger checks elicited less P100m activation. With 120' checks, we found no P100m attenuation as ISI decreased from 4 s to 0.16 s. P100m sources around the calcarine sulcus did not vary with check size or ISI.

Conclusions:

The magnitude of cortical activation during visual contrast processing is check size-dependent and the 120' checks are optimum for future studies on neuromagnetic visual cortical functions using central-occluded stimulation. The corresponding neuronal activation demonstrated a short refractory period less than 0.16 s. We also found significantly overlapping cortical representation areas for different check sizes or ISIs.

The forkhead transcription factor FOXO1 stimulates the expression of the adipocyte resistin gene

Resistin is known as an adipocyte-specific hormone that can cause insulin resistance and decrease adipocyte differentiation. It can be regulated by transcriptional factors, but the possible role of forkhead transcription factor FOXO1 in regulating resistin gene expression is still unknown. Using 3T3 fibroblast and C3H10T1/2 and 3T3-L1 adipocytes, we found that transient overexpression of a non-phosphorylatable, constitutively active FOXO1, but not the wild type of FOXO1 or a DNA binding-deficient FOXO1, activated resistin promoter-directed luciferase expression. However, transient overexpression of a dominant-negative FOXO1 inactivated resistin promoter activity and reduced resistin mRNA expression. These observations indicate that the action of FOXO1 on resistin gene expression requires the activation of FOXO1 and that the effect of FOXO1 depends on the phosphorylation and dephosphorylation of FOXO1. The FOXO1 protein target sites on the resistin promoter were localized to the proximal -3545 to -787bp of 5'-flanking region of the resistin promoter. A chromatin immunoprecipitation assay also showed that FOXO1 bound the resistin promoter at nucleotide regions of -1539 to -1366bp and -1016 to -835bp, but not at the regions of -795 to -632bp. Results of this study suggest that FOXO1 transcription factor likely activates the expression of adipocyte resistin gene via direct association with the upstream resistin promoter.

Side of the stimulated ear influences the hemispheric balance in coding tonal stimuli

OBJECTIVE

To evaluate whether the side of stimulated ear affects the hemispheric asymmetry of auditory evoked cortical activations.

METHODS

Using a whole-head neuromagnetometer, we recorded neuromagnetic approximately 100 ms responses (N100m) in 21 healthy right-handers to 100 ms 1 kHz tones delivered alternatively to left and right ear.

RESULTS

Although the peak latencies of N100m were shorter in contralateral than in ipsilateral hemisphere, the difference was significant only for the left ear stimulation. Based on the relative N100m amplitudes across hemispheres, the laterality evaluation showed a rightward predominance of N100m activation to tone stimuli, but the lateralization toward the right hemisphere was more apparent by the left than by the right ear stimulation (laterality index: -0.27 versus -0.10, p=0.008). Within the right hemisphere, the N100m was 2-4 mm more posterior for left ear than for right ear stimulation.

CONCLUSIONS

The hemispheric asymmetry in auditory processing depends on the side of the stimulated ear. The more anterior localization of right N100m responses to ipsilateral than to contralateral ear stimulation suggests that there might be differential neuronal populations in the right hemisphere for processing spatially different auditory inputs.

Generation and analysis of the expressed sequence tags from the mycelium of Ganoderma lucidum

Ganoderma lucidum (G. lucidum) is a medicinal mushroom renowned in East Asia for its potential biological effects. To enable a systematic exploration of the genes associated with the various phenotypes of the fungus, the genome consortium of G. lucidum has carried out an expressed sequence tag (EST) sequencing project. Using a Sanger sequencing based approach, 47,285 ESTs were obtained from in vitro cultures of G. lucidum mycelium of various durations. These ESTs were further clustered and merged into 7,774 non-redundant expressed loci. The features of these expressed contigs were explored in terms of over-representation, alternative splicing, and natural antisense transcripts. Our results provide an invaluable information resource for exploring the G. lucidum transcriptome and its regulation. Many cases of the genes over-represented in fast-growing dikaryotic mycelium are closely related to growth, such as cell wall and bioactive compound synthesis. In addition, the EST-genome alignments containing putative cassette exons and retained introns were manually curated and then used to make inferences about the predominating splice-site recognition mechanism of G. lucidum. Moreover, a number of putative antisense transcripts have been pinpointed, from which we noticed that two cases are likely to reveal hitherto undiscovered biological pathways. To allow users to access the data and the initial analysis of the results of this project, a dedicated web site has been created at http://csb2.ym.edu.tw/est/.

Effect of growth hormone on dawn phenomenon in patients with type 2 diabetes

We aimed to investigate the involvement of growth hormone in dawn phenomenon and insulin sensitivity in patients with type 2 diabetes mellitus (T2DM). On six occasions separated by intervals of at least 3 days, subjects received early evening (16:00 hours) or late night (23:00 hours) pretreatment with subcutaneous injection of normal saline, human growth hormone, or octreotide. Modified euglycemic insulin clamp test was done 16 hours later and variable glucose infusion (M values) was determined. Plasma glucose, serum insulin, insulin-like growth factor-1, non-esterified fatty acids, and metabolic clearance rate of insulin (MCRI) were measured. Early evening application of growth hormone decreased MCRI 16 hours later, suggesting reduction in insulin sensitivity. Exogenous growth hormone injection reduced insulin sensitivity in T2DM patients. Results provide direct evidence for the role of growth hormone in regulating the insulin sensitivity in insulin-resistant patients.

Trans-ethnic fine-mapping of lipid loci identifies population-specific signals and allelic heterogeneity that increases the trait variance explained

Genome-wide association studies (GWAS) have identified ∼100 loci associated with blood lipid levels, but much of the trait heritability remains unexplained, and at most loci the identities of the trait-influencing variants remain unknown. We conducted a trans-ethnic fine-mapping study at 18, 22, and 18 GWAS loci on the Metabochip for their association with triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), respectively, in individuals of African American (n = 6,832), East Asian (n = 9,449), and European (n = 10,829) ancestry. We aimed to identify the variants with strongest association at each locus, identify additional and population-specific signals, refine association signals, and assess the relative significance of previously described functional variants. Among the 58 loci, 33 exhibited evidence of association at P<1×10⁻⁴ in at least one ancestry group. Sequential conditional analyses revealed that ten, nine, and four loci in African Americans, Europeans, and East Asians, respectively, exhibited two or more signals. At these loci, accounting for all signals led to a 1.3- to 1.8-fold increase in the explained phenotypic variance compared to the strongest signals. Distinct signals across ancestry groups were identified at PCSK9 and APOA5. Trans-ethnic analyses narrowed the signals to smaller sets of variants at GCKR, PPP1R3B, ABO, LCAT, and ABCA1. Of 27 variants reported previously to have functional effects, 74% exhibited the strongest association at the respective signal. In conclusion, trans-ethnic high-density genotyping and analysis confirm the presence of allelic heterogeneity, allow the identification of population-specific variants, and limit the number of candidate SNPs for functional studies.

Lipid traits are heritable, but many of the DNA variants that influence lipid levels remain unknown. In a genomic region, more than one variant may affect gene expression or function, and the frequencies of these variants can differ across populations. Genotyping densely spaced variants in individuals with different ancestries may increase the chance of identifying variants that affect gene expression or function. We analyzed high-density genotyped variants for association with TG, HDL-C, and LDL-C in African Americans, East Asians, and Europeans. At several genomic regions, we provide evidence that two or more variants can influence lipid traits; across loci, these additional signals increase the proportion of trait variation that can be explained by genes. At some association signals shared across populations, combining data from individuals of different ancestries narrowed the set of likely functional variants. At PCSK9 and APOA5, the data suggest that different variants influence trait levels in different populations. Variants previously reported to alter gene expression or function frequently exhibited the strongest association at those signals. The multiple signals and population-specific characteristics of the loci described here may be shared by genetic loci for other complex traits.

Human chorionic gonadotropin regulates gastric emptying in ovariectomized rats

Prolongation of gastrointestinal transit resulting in nausea and vomiting in pregnancy (NVP) is the most common phenomenon during the first trimester of pregnancy. Increased human chorionic gonadotropin (hCG) concentration during the first trimester is the most likely cause of NVP. The aim of this study was to investigate the effect of hCG on gastrointestinal transit and plasma concentrations of cholecystokinin (CCK) in ovariectomized (Ovx) rats. I.p. injection of hCG was used to evaluate the dose effect of hCG on gastrointestinal transit in Ovx rats. The CCK antagonist lorglumide was used to clarify the role of CCK in regulating gastrointestinal transit. Gastrointestinal transit was assessed 15 min after intragastric gavage of a mixture of 10% charcoal and Na(2)(51)CrO(4) (0.5 μCi/ml). After i.p. administration of hCG, gastric emptying was inhibited in Ovx rats, but intestinal transit was not affected. Plasma CCK concentrations were increased in a dose-dependent manner after hCG treatment, and gastric emptying showed a significant negative correlation with CCK concentrations (P=0.01, r(2)=-0.5104). Peripheral administration (i.p.) of lorglumide, a selective CCK(1) receptor antagonist, attenuated the hCG-induced inhibition of gastric emptying in Ovx rats, whereas central administration via the i.c.v. route did not. hCG treatment of Ovx rats inhibits gastric emptying in a dose-dependent manner via a peripheral mechanism of CCK hypersecretion and activation of CCK(1) receptors.

Prunellae Spica Extract Contains Antagonists for Human Endothelin Receptors

Endothelin-1 (ET-1) is a powerful vasoconstrictor that contributes to blood pressure elevation. The biological effects of ETs are mediated by two receptors, namely, endothelin type A receptor (ETAR) and endothelin type B receptor (ETBR). Chinese herbal medicines (CHM) with antagonist activity for these two receptors were screened by establishing stable clones of CHO-K1 cells expressing high levels of human ETAR and ETBR, namely CHO-ETAR and CHO-ETBR.The aqueous extract of Prunellae Spica (P1) inhibited the binding of 125I-ET-1 to ETAR and ETBR in CHO-ETAR and CHO-ETBR cells, respectively. P1 suppressed the ET-1-induced mobilization of intracellular Ca2+ . Through the alcohol fractionation of P1, the antagonists of human ETAR and ETBR were found to belong to different, separable ingredients and the antagonist of ETAR is more soluble in alcohol. The two antagonists were also effective in the test on human primary cells, HASMC and HUVEC. P1 successfully prevented the development of ET-1-associated hypertension in rats without further purification. These results indicate the presence of anti-hypertensive ingredients in P. Spica extract, at least through the inactivation of ETAR and/or ETBR.

Endothelin Type A Receptor Genotype is a Determinant of Quantitative Traits of Metabolic Syndrome in Asian Hypertensive Families: A SAPPHIRe Study

Co-heritability of hypertension and insulin resistance (IR) within families not only implies genetic susceptibility may be responsible for these complex traits but also suggests a rational that biological candidate genes for hypertension may serve as markers for features of the metabolic syndrome (MetS). Thus we determined whether the T323C polymorphism (rs5333) of endothelin type A (ETA) receptor, a predominant receptor evoking potent vasoconstrictive action of endothelin-1, contributes to susceptibility to IR-associated hypertension in 1694 subjects of Chinese and Japanese origins. Blood pressures (BPs) and biochemistries were measured. Fasting insulin level, insulin-resistance homeostasis model assessment (HOMAIR) score, and area under curve of insulin concentration (AUCINS) were selected for assessing insulin sensitivity. Genotypes were obtained by methods of polymerase chain reaction-restriction fragment length polymorphism. Foremost findings were that minor allele frequency of the T323C polymorphism was noticeable lower in our overall Asian subjects compared to multi-national population reported in gene database; moreover both the genotypic and allelic frequencies of the polymorphism were significantly different between the two ethnic groups we studied. The genotype distributions at TT/TC/CC were 65, 31, 4% in Chinese and 51, 41, 8% in Japanese, respectively (p < 0.0001). Additionally, carriers of the C homozygote revealed characteristics of IR, namely significantly higher levels of fasting insulin, HOMAIR score, and AUCINS at 29.3, 35.3, and 39.3%, respectively, when compared to their counterparts with TT/TC genotypes in Chinese. Meanwhile, the CC genotype was associated with a higher level of high density lipoprotein cholesterol in Japanese. No association of the polymorphism with BP was observed. This study demonstrated for the first time that T323C polymorphism of ETA receptor gene was associated with an adverse insulin response in Chinese and a favorite atherogenic index in Japanese.

National trends in anti-diabetic treatment in Taiwan, 2000-2009

BACKGROUND/PURPOSE

The impact of the introduction of newer anti-diabetic agents on the treatment pattern in the booming diabetic population remains unclear. We examined the patterns and temporal trends of anti-diabetic drug use in Taiwan, with particular emphasis on combination therapy.

METHODS

We searched the Taiwan National Health Insurance Database during 2000-2009 to identify outpatient prescriptions of anti-diabetic drugs, including human insulins and insulin analogues, sulfonylureas, glinides, metformin, thiazolidinediones, alpha-glucosidase inhibitors, and dipeptidyl peptidase-4 inhibitors. Glucose-lowering treatments were classified according to pattern (oral agents only, insulins only, and oral agents and insulins combined) and a number of different classes of anti-diabetic drugs. Insulin therapy and combination therapy with two oral anti-diabetic drugs (OAD) were further classified according to individual drug combination patterns.

RESULTS

Although metformin remained the mainstay of anti-diabetic treatment, patients receiving combination therapy of oral glucose-lowering agents, either with or without insulin, significantly increased, from approximately 40% in 2000 to 60% in 2009, particularly in relation to the newer agents, including glinides, alpha-glucosidase inhibitors, and long-acting insulin analogues. Use of sulfonylureas and thiazolidinediones decreased substantially. For insulin therapy, the most commonly prescribed drugs were premix insulin analogues and basal insulin analogues, accounting for one-third of total insulin prescriptions in 2009.

CONCLUSION

We found an increasing complexity of anti-diabetic therapy during the past decade in Taiwan. Further studies are needed to evaluate whether this treatment pattern will lead to improved clinical outcomes in terms of cost-effectiveness.

The GIANT study, a cluster-randomised controlled trial of efficacy of education of doctors about type 2 diabetes mellitus management guidelines in primary care practice

OBJECTIVES

Primary aim: does general practitioner (GP) education on type 2 diabetes treatment improve HbA1c? Secondary aim: cardiovascular risk factors, hypoglycaemia, treatment intensification, health service utilisation, treatment barriers.

METHODS

99 Asia-Pacific GPs were cluster-randomised to be educated on regional diabetes management guidelines (intervention) or continue standard care (control). The intervention employed meetings, reminders, medical record summary sheets and patient result cards. Each GP recruited four type 2 diabetic patients, assessed at baseline, 6 and 12 months. The primary outcome was mean change in HbA1c from 0 to 6 months in patients with baseline HbA1c≥6.5%.

RESULTS

361 patients (93%) completed 6 month follow-up. The primary HbA1c outcome was -0.11% (95% CI -0.27, 0.05) with intervention and -0.22% (95% CI -0.39, -0.05) in the control group (p=0.340). The groups did not differ in control of other glycaemic indices, blood pressure or lipids after 6 or 12 months. In those with HbA1c≥9.0%, approximately 50% received intensified treatment by 6 months, and 30% in the final 6 months. GPs identified treatment costs and patient reluctance to use insulin as management barriers.

CONCLUSIONS/INTERPRETATION

A structured GP education programme did not improve HbA1c in patients with type 2 diabetes.

Endothelin-1 stimulates suppressor of cytokine signaling-3 gene expression in adipocytes

Endothelin (ET)-1 and suppressor of cytokine signaling (SOCS)-3 were respectively found to regulate energy metabolism and hormone signaling in fat cells. Although ET-1 can also regulate the expression of SOCS-3-stimulating hormones, it is still unknown whether ET-1 regulates SOCS-3 gene expression. This study investigated the pathways involved in ET-1's modulation of SOCS-3 gene expression in 3T3-L1 adipocytes. ET-1 upregulated SOCS-3 mRNA and protein expression in dose- and time-dependent manners. The concentration of ET-1 that increased SOCS-3 mRNA levels by 250-400% was ∼100nM with 2-4h of treatment. Treatment with actinomycin D prevented ET-1-stimulated SOCS-3 mRNA expression, suggesting that the effect of ET-1 requires new mRNA synthesis. Pretreatment with the ET type A receptor (ET(A)R) antagonist, BQ-610, but not the ET type B receptor (ET(B)R) antagonist, BQ-788, prevented the stimulatory effect of ET-1 on SOCS-3 gene expression. The specific inhibitors of either MEK1 (U-0126 and PD-98059), JAK (AG-490), JNK (SP-600125), or PI3K (LY-294002 and wortmannin) reduced ET-1-increased levels of SOCS-3 mRNA and respectively inhibited ET-1-stimulated activities of MEK1, JAK, JNK, and PI3K. These results imply that the ET(A)R, ERK, JAK, JNK, and PI3K are functionally necessary for ET-1's stimulation of SOCS-3 gene expression. Moreover, ET-1 was observed to upregulate expressions of SOCS-1, -2, -3, -4, -5, and -6 mRNAs, but not SOCS-7 or cytokine-inducible SH2-containing protein-1 mRNAs. This suggests that ET-1 selectively affects particular types of SOCS family members. Changes in SOCS gene expressions induced by ET-1 may help explain the mechanism by which ET-1 modulates hormone signaling of adipocytes.

Common ALDH2 genetic variants predict development of hypertension in the SAPPHIRe prospective cohort: gene-environmental interaction with alcohol consumption

Background

Genetic variants near/within the ALDH2 gene encoding the mitochondrial aldehyde dehydrogenase 2 have been associated with blood pressure and hypertension in several case–control association studies in East Asian populations.

Methods

Three common tag single nucleotide polymorphisms (tagSNP) in the ALDH2 gene were genotyped in 1,134 subjects of Chinese origin from the Stanford Asia-Pacific Program for Hypertension and Insulin Resistance (SAPPHIRe) family cohort. We examined whether the ALDH2 SNP genotypes predicted the development of hypertension in the prospective SAPPHIRe cohort.

Results

Over an average follow-up period of 5.7 years, carriers homozygous for the rs2238152 T allele in the ALDH2 gene were more likely to progress to hypertension than were non-carriers (hazard ratio [HR], 2.88, 95% confidence interval [CI], 1.06-7.84, P = 0.03), corresponding to a population attributable risk of ~7.1%. The risk associated with the rs2238152 T allele were strongest in heavy/moderate alcohol drinkers and was reduced in non-drinkers, indicating an interaction between ALDH2 genetic variants and alcohol intake on the risk of hypertension (P for interaction = 0.04). The risk allele was associated with significantly lower ALDH2 gene expression levels in human adipose tissue.

Conclusion

ALDH2 genetic variants were associated with progression to hypertension in a prospective Chinese cohort. The association was modified by alcohol consumption.

The effects of altitude training on the AMPK-related glucose transport pathway in the red skeletal muscle of both lean and obese Zucker rats

INTRODUCTION

The skeletal muscle AMP-activated protein kinase (AMPK)-related glucose transport pathway is involved in glucose homeostasis.

AIM

In this study, we examined whether obese control Zucker rats had abnormal expression of proteins in the LKB1-AMPK-AS160-GLUT4 pathway in red gastrocnemius muscle compared to that in lean (normal) control Zucker rats. We also compared the chronic training effects of exercise, hypoxia, and altitude training on this pathway in lean and obese rats.

METHODS

At sea level, lean and obese rats were divided into 4 groups for 6 weeks training as follows: 1) control; 2) exercise (progressive daily swimming-exercise training with comparable exercise signals between the two groups); 3) hypoxia (8 hours of daily 14% O2 exposure); and 4) exercise plus hypoxia (also called altitude training). Seven animals were used for each group.

RESULTS

The obese rats in the control group had higher body weights, elevated fasting insulin and glucose levels, and higher baseline levels of muscle AMPK and AS160 phosphorylation compared with those of lean control rats. For obese Zucker rats in the exercise or hypoxia groups, the muscle AMPK phosphorylation level was significantly decreased compared with that of the control group. For obese Zucker rats in the altitude training group, the levels of AMPK, AS160 phosphorylation, fasting insulin, and fasting glucose were decreased concomitant with an approximate 50% increase in the muscle GLUT4 protein level compared with those of the control group. In lean rats, the altitude training efficiently lowered fasting glucose and insulin levels and increased muscle AMPK and AS160 phosphorylation as well as GLUT4 protein levels.

CONCLUSION

Our results provide evidence that long-term altitude training may be a potentially effective nonpharmacological strategy for treating and preventing insulin resistance based on its effects on the skeletal muscle AMPK-AS160-GLUT4 pathway.

Quantification of Electroacupuncture-Induced Neural Activity by Analysis of Functional Neural Imaging with Monocrystalline Iron Oxide Nanocolloid Enhancement

The purpose of this study was to investigate the neural activity of electroacupuncture (EA) quantitatively. The responses of Sprague–Dawley rats' brain to EA on acupoints — Hegu (LI 4) and Neiguan (PC 6) — were detected by monocrystalline iron oxide nanoparticle (MION)-enhanced functional magnetic resonance imaging (MION-fMRI), which is a 1.5 T horizontal spectrometer equipped with a circular polarized extremity coil. During EA at LI 4, neural activities were analyzed by analysis of functional neural images (AFNI). Neural activation was detected at the structures of hypothalamus, thalamus, hippocampus, and the cortex, while neural deactivation existed at the areas adjacent to the activated sites. EA on PC 6 activated the structures of thalamus and the cortex but deactivated the structures of hypothalamus and hippocampus. The brain responses to EA existed in different areas of activation and deactivation despite stimulating the same acupoint. Additionally, distinct brain neuroimages were produced through stimulating different acupoints. This study suggests that fMRI with AFNI is a good approach to quantifying brain activities. This innovative method brings new perspective into the mechanisms of acupuncture.

Expression levels of vascular cell adhesion molecule-1 in young and nonobese women with polycystic ovary syndrome

BACKGROUND/AIMS

The objective of this study was to measure levels of mRNAs for inflammatory markers and resistin in human peripheral blood mononuclear cells (PBMCs) in young and nonobese women with polycystic ovary syndrome (PCOS).

METHODS

Fifteen young, nonobese women with PCOS and 10 age-matched controls were enrolled in this study. Levels of mRNAs for resistin and the inflammatory markers interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human PBMCs were measured using real-time PCR.

RESULTS

The mean age and BMI of the women with PCOS were 27.54 ± 6.3 years and 27.4 ± 5.7, respectively. The women with PCOS had significantly higher fasting and 2-hour insulin levels, homeostasis model assessment of insulin resistance index (HOMA(IR)) and total cholesterol levels than the controls. VCAM-1 and ICAM-1 mRNA levels were significantly higher in women with PCOS than in controls, whereas no differences in resistin, IL-6, TNF-α and MCP-1 mRNA levels were observed between the groups. After adjusting for the BMI, only VCAM-1 mRNA levels were significantly higher in women with PCOS than in controls and correlated with the HOMA(IR) and total cholesterol.

CONCLUSION

Elevated VCAM-1 in human PBMCs in young, nonobese women with PCOS is associated with insulin resistance, independent of the BMI.

Potential effect of resistin on the ET-1-increased reactions of blood pressure in rats and Ca2+ signaling in vascular smooth muscle cells

Resistin and endothelin-1 (ET-1) are upregulated in people with type II diabetes mellitus, central obesity, and hypertension. ET-1 signaling is involved in Ca(2+)-contraction coupling and related to blood pressure regulation. The aim of this study is to investigate the role of resistin on ET-1-increased blood pressure and Ca(2+) signaling. The blood pressure and cytosolic Ca(2+) of vascular smooth muscle cells (VSMCs) of Sprague-Dawley rats were detected. The data demonstrated that resistin accelerated and prolonged ET-1-induced increases in blood pressure and had significant effects on ET-1-increased Ca(2+) reactions. Resistin-enhanced ET-1-increased Ca(2+) reactions were reversed by blockers of store-operated Ca(2+) entry (SOCE) and extracellular-signal-regulated kinase (ERK). The endogenous expression of Orai and stromal interaction molecular (STIM) were characterized in the VSMCs. Furthermore, resistin-enhanced ET-1 Ca(2+) reactions and the resistin-dependent activation of SOCE were abolished under STIM1-siRNA treatment, indicating that STIM1 plays an important role in resistin-enhanced ET-1 Ca(2+) reactions in VSMCs. Resistin appears to exert effects on ET-1-induced Ca(2+) increases by enhancing the activity of ERK-dependent SOCE (STIM1-partcipated), and may accelerate and prolong ET-1-increased blood pressure via the same pathway.

Resistin induces monocyte-endothelial cell adhesion by increasing ICAM-1 and VCAM-1 expression in endothelial cells via p38MAPK-dependent pathway

Resistin, firstly reported as an adipocyte-specific hormone, is suggested to be an important link between obesity and diabetes. Recent studies have suggested an association between resistin and atherogenic processes. The adhesion of circulating monocytes to endothelial cells is a critical step in the early stages of atherosclerosis. The purpose of the present study was to investigate the effect of resistin on the adhesion of THP-1 monocytes to human umbilical vein endothelial cells (HUVECs) and the underlying mechanism. Our results showed that resistin caused a significant increase in monocyte adhesion. In exploring the underlying mechanisms of resistin action, we found that resistin-induced monocyte adhesion was blocked by inhibition of p38MAPK activation using SB203580 and SB202190. Furthermore, resistin increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by HUVECs and these effects were also p38MAPK-dependent. Resistin-induced monocyte adhesion was also blocked by monoclonal antibodies against ICAM-1 and VCAM-1. Taken together, these results show that resistin increases both the expression of ICAM-1 and VCAM-1 by endothelial cells and monocyte adhesion to HUVECs via p38MAPK-dependent pathways.

Endothelin-1 exacerbates lipid accumulation by increasing the protein degradation of the ATP-binding cassette transporter G1 in macrophages

Endothelin-1 (ET-1), a potent proatherogenic vasoconstrictive peptide, is known to promote macrophage foam cell formation via mechanisms that are not fully understood. Excessive lipid accumulation in macrophages is a major hallmark during the early stages of atherosclerotic lesions. Cholesterol homeostasis is tightly regulated by scavenger receptors (SRs) and ATP-binding cassette (ABC) transporters during the transformation of macrophage foam cells. The aim of this study was to investigate the possible mechanisms by which ET-1 affects lipid accumulation in macrophages. Our results demonstrate that oxidized low-density lipoprotein (oxLDL) treatment increases lipid accumulation in rat bone marrow-derived macrophages. Combined treatment with ET-1 and oxLDL significantly exacerbated lipid accumulation in macrophages as compared to treatment with oxLDL alone. The results of Western blotting show that ET-1 markedly decreased the ABCG1 levels via ET type A and B receptors and activation of the phosphatidylinositol 3-kinase pathway; however, ET-1 had no effect on the protein expression of CD36, SR-BI, SR-A, or ABCA1. In addition, real-time PCR analysis showed that ET-1 treatment did not affect ABCG1 mRNA expression. We also found that ET-1 decreases ABCG1 possibly due to the enhancement of the proteosome/calpain pathway-dependent degradation of ABCG1. Moreover, ET-1 significantly reduced the efficiency of the cholesterol efflux in macrophages. Taken together, these findings suggest that ET-1 may impair cholesterol efflux and further exacerbate lipid accumulation during the transformation of macrophage foam cells.

Removal of single point diamond-turning marks by abrasive jet polishing

Single point diamond turning (SPDT) is highly controllable and versatile in producing axially symmetric forms, non-axially-symmetric forms, microstructured surfaces, and free forms. However, the fine SPDT marks left in the surface limit its performance, and they are difficult to reduce or eliminate. It is unpractical for traditional methods to remove the fine marks without destroying their forms, especially for the aspheres and free forms. This paper introduces abrasive jet polishing (AJP) for the posttreatment of diamond-turned surfaces to remove the periodic microstructures. Samples of diamond-turned electroless nickel plated plano mirror were used in the experiments. One sample with an original surface roughness of more than 400 nm decreased to 4 nm after two iterations abrasive jet polishing; the surface roughness of another sample went from 3.7 nm to 1.4 nm after polishing. The periodic signatures on both of the samples were removed entirely after polishing. Contrastive experimental research was carried out on electroless nickel mirror with magnetorheological finishing, computer controlled optical surfacing, and AJP. The experimental results indicate that AJP is more appropriate in removing the periodic SPDT marks. Also, a figure maintaining experiment was carried out with the AJP process; the uniform polishing process shows that the AJP process can remove the periodic turning marks without destroying the original form.

Comprehensive risk assessments of diabetic patients from seven Asian countries: The Joint Asia Diabetes Evaluation (JADE) program

BACKGROUND

 The aim of the web-based Joint Asia Diabetes Evaluation (JADE) program is to establish a registry for quality assurance, monitoring, and evaluation.

METHODS

 The JADE electronic portal provides templates for data collection, supplemented by risk stratification, care protocols, and decision support. Herein, data from 3687 patients with Type 2 diabetes, enrolled over 15 months in 2007-2009 from seven Asian countries, are reported.

RESULTS

Of the patients, 46.1% were men, the median (range) age was 58 (15-93 years), and median disease duration was 6.5 (0-71) years; 16.2% had at least one cardiovascular-renal complication (10.0% coronary heart disease, 3.3% stroke, 3.1% peripheral vascular disease, 0.4% end-stage renal disease), 20.4% had diabetic retinopathy, 15.0% had sensory neuropathy, 7.5% had chronic kidney disease, and 20.7% of men had erectile dysfunction. Hypertension, dyslipidemia, and central obesity affected 84.6%, 76.8%, and 53.5% of patients, respectively. Treatment targets were HbA1c <7% in 35.3%, blood pressure <130/80 mmHg in 32.3%, and low-density lipoprotein-cholesterol <2.6 mmol/L in 34.0%. The rate of attaining one, two, and three targets was 38.7%, 23.4%, and 5.4%, respectively. Using the JADE Risk Engine, 60% of patients with clinical complications and 20% of those with multiple risk parameters were predicted to have a major event within 5 years. Older age, short disease duration, adherence to diet, control of other risk factors, and not smoking were independently associated with HbA1c <7% (all P < 0.05).

CONCLUSIONS

 It is possible to use a web-based protocol to establish a registry for risk stratification and facilitate early intervention.

Perturbations of the stress-induced GLUT4 localization pathway in slow-twitch muscles of obese Zucker rats

Past studies have suggested that the stress-induced GLUT4 localization pathway is damaged in fast-twitch muscles (white muscles) of obese subjects. In this study, we used obese rodents in an attempt to determine whether the stress-induced GLUT4 localization pathway is abnormal in slow-twitch muscles (red muscles), which are responsible for most daily activities. Protein expression levels of the intracellular stress sensor AMP-activated protein kinase (AMPK), its upstream kinase LKB1, its downstream protein AS160 and the glucose transporter protein 4 (GLUT4) in the red gastrocnemius muscle were measured under either resting or stress conditions (1 h of swimming or 14% hypoxia) in both lean and obese Zucker rats (n = 7 for each group). At rest, obese rats displayed higher fasting plasma insulin levels and increased muscle AMPK and AS160 phosphorylation levels compared with lean controls. No significant difference was found in the protein levels of LKB1, total GLUT4, or membrane GLUT4 between the obese and lean control groups. After one hour of swimming, AMPK and AS160 phosphorylation levels and the amount of GLUT4 translocated to the plasma membrane were significantly elevated in lean rats but remained unchanged in obese rats relative to their resting conditions. One hour 14% hypoxia did not cause significant changes in the LKB1-AMPK-AS160-GLUT4 pathway in either lean or obese rats. This study demonstrated that the AMPK-AS160-GLUT4 pathway was altered at basal levels and after exercise stimulation in the slow-twitch muscle of obese Zucker rats.

Insulin up-regulates heme oxygenase-1 expression in 3T3-L1 adipocytes via PI3-kinase- and PKC-dependent pathways and heme oxygenase-1-associated microRNA downregulation

Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme catabolism, has antioxidant, antiinflammatory, and antiapoptotic effects in many physiological systems. HO-1 activity in obese mice is lower than in controls, and a sustained increase in HO-1 protein levels ameliorates insulin resistance and compensatory hyperinsulinemia. In the present study, we explored the regulatory effect of insulin on HO-1 expression in 3T3-L1 adipocytes and the underlying mechanism. We investigated the time- and dose-effect of insulin on HO-1 expression in 3T3-L1 adipocytes. Using specific inhibitors acting on insulin signaling pathways, we clarified the involvement of insulin downstream signaling molecules in insulin-regulated HO-1 expression. We also investigated the involvement of microRNAs (miRNAs) in insulin-regulated HO-1 expression using microarray and real-time RT-PCR assays. In an in vivo study, we performed insulin/glucose coinfusion in rats to increase circulating insulin levels for 8 h, then measured adipocyte HO-1 expression. Insulin caused a significant increase in HO-1 expression that was time- and dose-dependent, and this effect was blocked by inhibition of phosphatidylinositol 3 (PI3)-kinase activation using LY294002 (50 μM) or of protein kinase C activation using Ro-318220 (2 μM), but not by an Akt inhibitor, triciribine (10 μM). Furthermore, incubation of 3T3-L1 adipocytes with 100 nm insulin resulted in a significant decrease in levels of the miRNAs mir-155, mir-183, and mir-872, and this effect was also blocked by pretreatment with LY294002 or Ro-318220, but not triciribine. An in vivo study in rats showed that 8 h of a hyperinsulinemic euglycemic state resulted in a significant increase in adipocyte HO-1 expression. In conclusion, insulin increases HO-1 protein expression in 3T3-L1 adipocytes via PI3-kinase and protein kinase C-dependent pathways and miRNAs down-regulation.

Proposals of statistical consideration to evaluation of results for a specific region in multi-regional trials--Asian perspective

In recent years, global collaboration has become a conventional strategy for new drug development. To accelerate the development process and to shorten approval time, the design of multi-regional trials incorporates subjects from many countries around the world under the same protocol. After showing the overall efficacy of a drug in all global regions, one can also simultaneously evaluate the possibility of applying the overall trial results to all regions and subsequently support drug registration in each of them. Recently, the trend for simultaneous clinical development in Asian countries being undertaken simultaneously with clinical trials conducted in Europe and the United States has been rapidly rising. In this paper, proposals of statistical consideration to multi-regional trials are provided. More specifically, three aspects are addressed: the definition of the 'Asian region,' the consistency criterion between the 'Asian region' and the overall regions, and the sample size determination for the multi-regional trial.

Islet isolation from human pancreas with extended cold ischemia time

The general consensus among transplant centers is that a cold ischemia time (CIT) beyond 8 hours results in reduced yields and quality of human islets. We sought to optimize the isolation process and enzymes for pancreata with extended CIT. We processed 16 extended CIT pancreata (13.2 +/- 0.7 hours). Donors averaged 50.8 +/- 2.6 (standard error of the mean) years old with a body mass index of 28.6 +/- 1.5. Glands were shipped in cold organ preservation solution without oxygenated perfluorocarbon. Isolations were performed under a protocol optimized for digestion with the new cGMP collagenase from Roche. Purification used continuous Euroficoll/University of Wisconsin gradients. Islets were cultured in two types of Prodo cGMP islet culture media and/or in Miami 1A media. Glucose-stimulated insulin secretion assays were performed after 8 to 16 days of culture. Prepurification yield averaged 415 +/- 41 KIEQ postpurification, 359 +/- 29 KIEQ (purification loss 13.5%); and postculture 317 +/- 27 KIEQ (culture loss 11.7%). Our process liberated an average of 4278 IEQ/g of pancreas (97 +/- 5 g). Most islets were recovered in the purest fraction (purity 79.7% +/- 1.9%). Culture loss in our enhanced culture media was 11.7%. After 2 to 3 days in culture, viability was 92% +/- 1%. Islets exhibited compactness and dithizone staining. Glucose-stimulated insulin secretion assays performed after 3 to 23 days in our PIM(R) media resulted in a stimulation index of 6.8 +/- 1.7 (G50 to G350). We concluded that our human islet isolation process permitted the recovery of large numbers of high-quality human islets from extended CIT pancreata and that our cGMP islet culture media was superior to the current standard CMRL-based media.

Justifying the high prevalence of microalbuminuria for type 2 diabetic patients in Taiwan with conditional probability approach--a DEMAND II study

BACKGROUND

To examine the prevalence of microalbuminuria (MAU) and chronic kidney disease as well as the correlation between MAU and renal and cardiovascular risks of Type 2 diabetes mellitus (T2DM) patients for public health policy making in Taiwan.

METHODS

This was a multicenter, hospital-based, randomly selected, and cross-sectional study. T2DM patients aged 18-80 years without a known diagnosis of proteinuria were eligible. MAU was defined as urinary albumin-to-creatinine ratio (ACR) within 30-299 mg/g, and macroalbuminuria as that greater than or equal to 300 mg/g. Two positive out of three urinary screening results were required to make the diagnosis of MAU. The adjusted prevalence of MAU was calculated by conditional probability approach.

RESULTS

51.1% of the analyzed population (n=1,827) were women, with a mean (standard deviation) age of 59.16 years (11.19 years) and mean hemoglobin A1c (HbA1c) of 8.15% (1.83%). Median duration of DM history was 6 years (interquartile range, 3-11 years). The adjusted prevalence of MAU was 26.9%. Overall prevalence of chronic kidney disease Stage 3 or higher (estimated Glomerular filtration rate (eGFR) less than 60/mL/min/1.73 m²) was 13.8%. Only 4.7% of the T2DM patients had serum albumin test recorded and 68.7% with serum creatinine test recorded within the last 6 months. After adjustment for center and gender, the odds ratios for MAU or macroalbuminuria were 1.73 (95% CI, 1.27-2.36) for age greater than or equal to 60 years, 1.54 (1.13-2.10) for abnormal waist circumference, 1.10 (1.02-1.19) for every 1% increase in hemoglobin A1c, 1.91 (1.38-2.65) for higher systolic blood pressure, and 1.92 (1.19-3.07) for abnormal serum creatinine level.

CONCLUSION

This study demonstrates the application of "conditional probability" method to justify the rationale of adopting two positive out of three urinary screening tests for the diagnosis of MAU. An adjusted prevalence rate of MAU as 26.9% is reported. These results may provide a basis for cost-benefit consideration in designing preventive and interventional policies in public health. Furthermore, the awareness and practice of early monitoring of MAU for DM patients should be strengthened.

Endothelin-1 suppresses long-chain fatty acid uptake and glucose uptake via distinct mechanisms in 3T3-L1 adipocytes

Endothelin-1 (ET-1) has been demonstrated to induce insulin resistance (IR) and lipolysis, raising the possibility that ET-1 may also contribute to the elevated fatty acid levels in IR-associated comorbidities. We attempted to evaluate whether ET-1 also affects the long-chain fatty acid (LCFA) utilization in 3T3-L1 adipocytes. The effects of chronic ET-1 exposure on basal and insulin-stimulated LCFA uptake, and LCFA uptake kinetics were examined in 3T3-L1 adipocytes. Chronic exposure to ET-1 induced IR and suppressed basal and insulin-stimulated LCFA uptake. Given that insulin acutely stimulates LCFA uptake, there was dramatically similar trend of dose-response curves for ET-1-suppressed LCFA uptake, and also similar corresponding IC₅₀ values, between basal and insulin-stimulated states, reflecting that ET-1 predominantly suppresses basal LCFA uptake. Results of LCFA kinetics, western blots, and CD36 inhibition using sulfosuccinimidyl oleate (SSO) revealed that suppression of LCFA uptake by ET-1 is associated with downregulation of CD36. ET type A receptor (ET(A)R) antagonist BQ-610 reversed the IR induction and the ET-1-suppressed LCFA uptake. Exogenous replenishment of phosphatidylinositol (PI) 4, 5-bisphosphate (PIP₂) prevented IR induction, but not the suppression of LCFA uptake by ET-1. Pharmacological inhibition of the activation of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) completely blocked the ET-1-suppressed LCFA uptake. Serving as an inducer of IR, ET-1 also chronically suppresses LCFA uptake via PIP₂-independent and ERK-dependent pathway. The interplay between impaired glucose disposal and diminished LCFA utilization, induced by ET-1, could worsen the dysregulation of adipose metabolism and energy homeostasis in insulin-resistant states.

Perspectives of CB1 Antagonist in Treatment of Obesity: Experience of RIO-Asia

Rimonabant, a selective cannabinoid-1 (CB1) receptor antagonist, has been shown to reduce weight and enhance improvements in cardiometabolic risk parameters in Western populations. This study assessed these effects of rimonabant in Asian population. A total of 643 patients (BMI 25 kg/m(2) or greater without diabetes) from China, Republic of Korea, and Taiwan were prescribed a hypocaloric diet (600 kcal/day deficit) and randomized to rimonabant 20 mg (n = 318) or placebo (n = 325) for 9months. The primary efficacy variable was weight change from baseline after 9 months of treatment. Results showed that rimonabant group lost more weight than placebo, (LSM ± SEM of -4.7 ± 0.3 kg vs. -1.7 ± 0.3 kg, P < .0001). The 5% and 10% responders were 2 or 3 folds more in the rimonabant group (53.0% vs. 20.0% and 21.5% vs. 5.7%, resp.) (P < .0001). Rimonabant also significantly increased HDL-cholesterol, decreased triglycerides and waist circumference,by 7.1%, 10.6%, and 2.8 cm, respectively (P < .0001). This study confirmed the comparable efficacy and safety profile of rimonabant in Asian population to Caucasians. Owing to the recent suspension of all the CB1 antagonists off the pharmaceutical market for weight reduction in Europe and USA, a perspective in drug discovery for intervening peripheral CB1 receptor in the management of obesity is discussed.

Genetic variants of human urea transporter-2 are associated with metabolic syndrome in Asian population

BACKGROUND

A previous study has reported that the Ile227 and Ala357 genetic variants of human urea transporter-2 (HUT2) were associated with blood pressure in males in Asian population. In this study, we aimed to investigate five known HUT2 genetic variants with metabolic syndrome (MetS) and its related traits in the Stanford Asia-Pacific Program for Hypertension and Insulin Resistance (SAPPHIRe) study cohort.

METHODS

Five HUT2 single nucleotide polymorphisms (SNPs) were selected and genotyped among 1791 subjects in the SAPPHIRe study cohort. We first computed allele frequency and performed Hardy-Weinberg equilibrium (HWE) test in controls for each SNP. Next, we tested genotype associations with metabolic syndrome using multiple generalized estimating equations (GEE) models with covariate adjustment. Furthermore, multi-marker and multi-trait association tests were carried out using FBAT program. To account for multiple testing, Bonferroni correction was applied in this study.

RESULTS

Among those 5 HUT2 SNPs, SNPs 1, 2 and 3 were significantly associated with MetS in the total sample and females, separately (9×10(-4)≤p≤0.04), but only the association between SNP 1 and MetS in females remained statistically significant after Bonferroni correction. When testing 5 SNPs simultaneously, significant associations were found with triglycerides (TG) (p=0.04). Likewise, significant multi-trait association (combining the data of waist circumference, TG, high density lipoprotein (HDL) cholesterol and fasting glucose together) was found with SNP 2 (p=0.04), but both results of multi-maker and multi-trait associations did not remain significant after multiple testing correction.

CONCLUSION

The results have provided evidence that the HUT2 gene may play a certain role in developing MetS and its related traits in Asian population. Further investigation of the HUT2 gene influencing MetS and its related traits will be warranted.