Dietary fatty acids differentially affect secretion of pro-inflammatory cytokines in human THP-1 monocytes.

Monocytes are a major population of circulating immune cells that play a crucial role in producing pro-inflammatory cytokines in the body. The actions of monocytes are known to be influenced by the combinations and concentrations of certain fatty acids (FAs) in blood and dietary fats. However, systemic comparisons of the effects of FAs on cytokine secretion by monocytes have not be performed. In this study, we compared how six saturated FAs (SFAs), two monounsaturated FAs (MUFAs), and seven polyunsaturated FAs (PUFAs) modulate human THP-1 monocyte secretion of TNF, IL-1ß, and IL-6 in the absence or presence of lipopolysaccharide. SFAs generally stimulated resting THP-1 cells to secrete pro-inflammatory cytokines, with stearic acid being the most potent species. In contrast, MUFAs and PUFAs inhibited lipopolysaccharide-induced secretion of pro-inflammatory cytokines. Interestingly, the inhibitory potentials of MUFAs and PUFAs followed U-shaped (TNF and IL-1ß) or inverted U-shaped (IL-6) dose-response curves. Among the MUFAs and PUFAs that were analyzed, docosahexaenoic acid (C22:6 n-3) exhibited the largest number of double bonds and was found to be the most potent anti-inflammatory compound. Together, our findings reveal that the chemical compositions and concentrations of dietary FAs are key factors in the intricate regulation of monocyte-mediated inflammation.

A randomized trial on the effect of transcutaneous electrical nerve stimulator on glycemic control in patients with type 2 diabetes.

Transcutaneous electrical nerve stimulator (TENS) has been demonstrated to be beneficial in glycemic control in animal models, but its application in humans has not been well studied. We randomly assigned 160 patients with type 2 diabetes on oral antidiabetic drugs 1:1 to the TENS study device (n = 81) and placebo (n = 79). 147 (92%) randomized participants (mean [SD] age 59 [10] years, 92 men [58%], mean [SD] baseline HbA1c level 8.1% [0.6%]) completed the trial. At week 20, HbA1c decreased from 8.1% to 7.9% in the TENS group (- 0.2% [95% CI - 0.4% to - 0.1%]) and from 8.1% to 7.8% in the placebo group (- 0.3% [95% CI - 0.5% to - 0.2%]) (P = 0.821). Glycemic variability, measured as mean amplitude of glycemic excursion (MAGE) at week 20 were significantly different in the TENS group vs. the placebo group (66 mg/dL [95% CI 58, 73] vs. 79 mg/dL [95% CI 72, 87]) (P = 0.009). Our study provides the clinical evidence for the first time in humans that TENS does not demonstrate a statistically significant HbA1c reduction. However, it is a safe complementary therapy to improve MAGE in patients with type 2 diabetes.

Growth differentiation factor-15 is independently associated with metabolic syndrome and hyperglycemia in non-elderly subjects.

Metabolic syndrome (MetS) is a major health issue worldwide accompanied by cardiovascular comorbidities. Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine expressed in cardiomyocytes, adipocytes, macrophages, and endothelial cells. Previous research in elderly subjects revealed that GDF-15 levels were associated with the MetS. However, the association between GDF-15 levels and MetS or its components in the non-elderly subjects remains unclear. In this study, a total of 279 subjects younger than 65-year-old with (n = 84) or without (n = 195) MetS were recruited. MetS was defined according to modified NCEP/ATP III criteria. The GDF-15 levels were measured by an enzyme-linked immunosorbent assay. A multiple linear regression analysis was conducted to identify factors independently associated with GDF-15 levels. Subjects with MetS had higher GDF-15 levels than those without MetS (median (interquartile range), 1.72 ng/mL (1.38, 2.26) vs. 1.63 ng/mL (1.27, 2.07), P = 0.037). With the number of MetS components increased, the GDF-15 levels increased significantly (P for trend = 0.005). Multiple linear regression analysis revealed that the presence of MetS was positively associated with the GDF-15 levels (ß = 0.132, P = 0.037). When substituting MetS with its components, only the presence of hyperglycemia was positively associated with the GDF-15 levels after adjustment for covariates (ß = 0.193, P = 0.003). Taken together, the presence of the MetS in non-elderly was associated with higher GDF-15 levels. Among the MetS components, only hyperglycemia was significantly associated with the GDF-15 levels. Future longitudinal studies will be needed to explore whether GDF-15 has the potential to be a biomarker of gluco-metabolic dysfunction in non-elderly subjects.

Real-World Comparative Evaluation of Add-On Glucagon-like Peptide 1 Receptor Agonist in Type 2 Diabetes Treated with or without Insulin.

Glucagon-like peptide 1 receptor agonist (GLP-1 RA) is a potent antidiabetic agent with cardiorenal and weight-losing benefits in patients with type 2 diabetes (T2D). The combination of GLP-1 RA with basal insulin has been suggested in several clinical studies as a useful treatment for intensifying insulin therapy in T2D. However, there has been no real-world evidence study comparing the glycemic effects of GLP-1 RAs add-on to background treatment with and without insulin. A retrospective study was performed in 358 patients with T2D who initiated liraglutide or dulaglutide. Among them, 147 patients were prior and concurrent insulin users, and 211 patients were non-insulin users. After 12 months of GLP-1 RA treatment, the changes in hemoglobin A1c (HbA1C) and body weight were evaluated. The effectiveness of GLP-1 RAs on HbA1C reduction was greater in insulin users than non-insulin users at 12 months (−1.17% vs. −0.76%; p = 0.018). There was no significant difference in body weight change between insulin users and non-insulin users at 12 months (−1.42 kg vs. −1.87 kg; p = 0.287). The proportion of responders (decrease of HbA1C > 1%) in insulin users was much higher than that in non-insulin users (48% vs. 37 %; p = 0.04). In insulin users, those who had increased insulin dosage at 12 months had significantly less HbA1C reduction than that of non-increased patients (−0.62% vs. −1.57%; p = 0.001). GLP-1 RAs provide superior glucose-lowering effects in insulin-treated patients compared with non-insulin-treated patients with T2D without significant differences in body weight decrease.

High glucose enhances lipopolysaccharide-induced inflammation in cultured BV2 microglial cell line.

INTRODUCTION: Diabetes mellitus emerges as a global health crisis and is related to the development of neurodegenerative diseases. Microglia, a population of macrophages-like cells, govern immune defense in the central nervous system. Activated microglia are known to play active roles in the pathogenesis of neurodegenerative diseases. METHODS: This study aimed to investigate the effects of high glucose on low-dose lipopolysaccharide (LPS)-induced activations of inflammation-related signaling molecules in cultured BV2 microglial cells. RESULTS: Compared to cells cultured in the normal glucose medium (NGM, 5.5 mM), the LPS-induced activation of NF-κB lasted longer in cells cultured in high glucose medium (HGM, 25 mM). HGM also enhanced the expression of inducible nitric oxide synthase (iNOS). Among the mitogen-activated protein kinases, HGM enhanced the LPS-induced phosphorylation of p38 without affecting the phosphorylation of Erk1/2 or JNK. BV2 cells cultured in HGM expressed higher levels of TLR4 than those cells cultured in NGM. CONCLUSION: High glucose aggravated LPS-induced inflammatory responses of microglia via enhancing the TLR4/p38 pathway and prolonging the activation of NF-κB/iNOS signaling. Controlling blood glucose levels is advised to manage neuroinflammation and related neurodegenerative diseases.

Associations between GDF15 levels and pre-diabetes in non-obese subjects.

Growth differentiation factor 15 (GDF15) is a stress-response cytokine which belongs to the transforming growth factor ß superfamily. Although GDF15 was initially found to have a role in metabolic diseases, the association between GDF15 and dysglycemic status remains inconclusive. Thus, the aim of this study was to examine the relationships between GDF15 and different glycemic statuses in non-obese subjects. We enrolled 502 non-obese subjects, among individuals who had normal glucose tolerance (NGT; n=125), isolated impaired fasting glucose (IFG; n=116), isolated impaired glucose tolerance (IGT; n=106), IFG plus IGT (n=27), and newly diagnosed diabetes (NDD; n=128). A multivariate linear regression analysis of GDF15 levels was used to find independent predictors. The median (IQR) GDF15 levels were 1641.0 (1187.0-1985.5) pg/mL, 1656.1 (1226.8-2379.7) pg/mL, 1487.8 (1145.9-1987.2) pg/mL, 1722.2 (1172.9-1939.0) pg/mL, and 2204.5 (1767.4-2919.1) pg/mL in NGT, IFG, IGT, IFG plus IGT, and NDD groups, respectively. The NDD group had significantly higher GDF15 levels than those with NGT, IFG, IGT, and IFG plus IGT. The IFG group had a significantly higher GDF15 value than the NGT group. In multivariate linear regression analysis, IFG (beta=0.145, 95% CI 192.487 to 740.937, p=0.001), NDD (beta=0.227, 95% CI 390.459 to 888.145, p<0.001), and high-sensitivity C reactive protein (beta=0.105, 95% CI 3.276 to 27.768, p=0.013) were independently associated with GDF15 levels. Non-obese subjects with isolated IFG and NDD had significantly higher GDF15 levels than those with NGT. In addition, A1C was independently associated with GDF15 levels. IFG and NDD, but not isolated IGT or IFG plus IGT, were positively associated with GDF15 levels.

High-fat diet-induced increases in glucocorticoids contribute to the development of non-alcoholic fatty liver disease in mice.

This study aimed to investigate the causal relationship between chronic ingestion of a high-fat diet (HFD)-induced secretion of glucocorticoids (GCs) and the development of non-alcoholic fatty liver disease (NAFLD). We have produced a strain of transgenic mice (termed L/L mice) that have normal levels of circulating corticosterone (CORT), the major type of GCs in rodents, but unlike wild-type (WT) mice, their circulating CORT was not affected by HFD. Compared to WT mice, 12-week HFD-induced fatty liver was less pronounced with higher plasma levels of triglycerides in L/L mice. These changes were reversed by CORT supplement to L/L mice. By analyzing a sort of lipid metabolism-related proteins, we found that expressions of the hepatic cluster of differentiation 36 (CD36) were upregulated by HFD-induced CORT and involved in CORT-mediated fatty liver. Dexamethasone, an agonist of the glucocorticoid receptor (GR), upregulated expressions of CD36 in HepG2 hepatocytes and facilitated lipid accumulation in the cells. In conclusion, the fat ingestion-induced release of CORT contributes to NAFLD. This study highlights the pathogenic role of CORT-mediated upregulation of hepatic CD 36 in diet-induced NAFLD.

The Serum Concentrations of Hedgehog-Interacting Protein, a Novel Biomarker, Were Decreased in Overweight or Obese Subjects.

Although it was known that obesity is an independent risk factor for metabolic disorders including diabetes, the factors that link these diseases were obscure. The Hedgehog-interacting protein (Hhip) is a negative regulator in tissue remodeling, and inhibits the proliferation of adipocytes, and promotes their differentiation. In addition, Hhip was positively associated with diabetes. However, the relationship between Hhip and obesity in the human body remains unclear. An analysis of the relationship between Hhip and normal weight, overweight, and obesity levels. Participants receiving a physical checkup were recruited. Anthropometric and biochemical data were collected. Serum Hhip levels were determined by enzyme-linked immunosorbent assay (ELISA). Subjects were classified into normal-weight, overweight, and obese groups based on their body mass index (BMI). The association between Hhip and obesity was examined by multivariate linear regression analysis. In total, 294 subjects who were either of a normal weight (n = 166), overweight (n = 90), or obese (n = 38) were enrolled. Hhip concentrations were 6.51 ± 4.86 ng/mL, 5.79 ± 4.33 ng/mL, and 3.97 ± 3.4 ng/mL in normal-weight, overweight, and obese groups, respectively (p for trend = 0.032). Moreover, the regression analysis showed that BMI (ß = -0.144, 95% confidence interval (CI) = -0.397-0.046, p = 0.013) was negatively associated with Hhip concentrations after adjusting for sex and age. Being overweight (ß = -0.181, 95% CI = -3.311-0.400, p = 0.013) and obese (ß = -0.311, 95% CI = -6.393-2.384, p < 0.001) were independently associated with Hhip concentrations after adjusting for sex, age, fasting plasma glucose, the insulin level, and other cardiometabolic risk factors. Our results showed that overweight and obese subjects had lower Hhip concentrations than those of normal weight. Being overweight and obese were negatively associated with Hhip concentrations. Hhip might be a link between obesity and diabetes.

Elevated Hedgehog-Interacting Protein Levels in Subjects with Prediabetes and Type 2 Diabetes.

BACKGROUND: The prevalence of diabetes is rapidly increasing worldwide and is highly associated with the incidence of cancers. In order to prevent diabetes, early diagnosis of prediabetes is important. However, biomarkers for prediabetes diagnosis are still scarce. The hedgehog-interacting protein (Hhip) is important in embryogenesis and is known to be a biomarker of several cancers. However, Hhip levels in subjects with diabetes are still unknown. METHODS: In total, 314 participants were enrolled and divided into normal glucose tolerance (NGT; n = 75), impaired fasting glucose (IFG; n = 66), impaired glucose tolerance (IGT; n = 86), and newly diagnosed diabetes (NDD; n = 87) groups. Plasma Hhip levels were determined by an ELISA. The association between the Hhip and the presence of diabetes was examined by a multivariate linear regression analysis. RESULTS: There were significant differences in the body mass index, systolic and diastolic blood pressure, fasting plasma glucose (FPG), post-load 2-h glucose, hemoglobin A1c (A1C), C-reactive protein, total cholesterol, triglyceride, and high- and low-density lipoprotein cholesterol levels among the groups. Concentrations of the Hhip were 2.45 ± 2.12, 4.40 ± 3.22, 4.44 ± 3.64, and 6.31 ± 5.35 ng/mL in subjects in the NGT, IFG, IGT, and NDD groups, respectively. In addition, we found that A1C and FPG were independently associated with Hhip concentrations. Using NGT as a reference group, IFG, IGT, and NDD were all independently associated with Hhip concentrations. CONCLUSIONS: Hhip was positively associated with prediabetes and type 2 diabetes mellitus.

Serum Secretogranin III Concentrations Were Increased in Subjects with Metabolic Syndrome and Independently Associated with Fasting Plasma Glucose Levels.

Secretogranin III (SCG3) plays a crucial role in the biogenesis of secretory granules in endocrine cells, and thus affects glucose homeostasis by regulating insulin secretion by pancreatic beta cells. Insulin resistance and compensatory hyperinsulinemia are hallmarks of metabolic syndrome (MetS). However, the role of SCG3 in MetS remains unclear. Therefore, we investigated the relationship between serum SCG3 levels and metabolic parameters in subjects with and without MetS. This was a case control study, and 295 subjects were recruited. Serum SCG3 concentrations were compared between groups. Associations between SCG3 levels and clinico-metabolic parameters were also examined. We found serum SCG3 levels were higher in the MetS group than non-MetS group (122.6 ± 79.2 vs. 90.6 ± 58.5 nmol/L, p = 0.009). Specifically, elevated SCG3 levels were found in subjects with high fasting plasma glucose (FPG) levels, central obesity, or hypertriglyceridemia. Additionally, MetS was an independent factor of serum SCG3 levels in multivariate linear regression analyses. Moreover, FPG, free fatty acids, and waist circumference were positively associated with serum SCG3 concentrations after adjusting for insulin levels, high-sensitivity C-reactive protein, and cardiovascular risk factors. In conclusion, serum SCG3 concentrations were higher in subjects with MetS and were independently associated with FPG levels.

Helicobacter pylori eradication improves glycemic control in type 2 diabetes patients with asymptomatic active Helicobacter pylori infection.

AIMS/INTRODUCTION: Helicobacter pylori infection is associated with insulin resistance and glycemia in non-diabetes. However, the relationship between H. pylori infection and glycemia in diabetes remains inconclusive. Therefore, we explored the effect of H. pylori infection status and its eradication on glycemic control and antidiabetic therapy in type 2 diabetes patients. MATERIALS AND METHODS: A total of 549 diabetes patients were recruited for sequential two-step approach (immunoglobulin G [IgG] serology followed by 13 C-urea breath test [UBT]) to discriminate "active" (IgG+ and UBT+) from "non-active" (UBT- or IgG-) H. pylori infection, and "past" (IgG+ but UBT-) from "never/remote" (IgG-) infection. The differences in hemoglobin A1c (A1C) and antidiabetic regimens between groups were compared. In the "active" infection group, the differences in A1C changes between participants with and without 10-day eradication therapy were compared after 3 months. RESULTS: Despite no between-group difference in A1C, the "active" infection group (n = 208) had significantly more prescriptions of oral antidiabetic drug classes (2.1 ± 1.1 vs 1.8 ± 1.1, P = 0.004) and higher percentages of sulfonylurea use (67.3% vs 50.4%, P < 0.001) than the "non-active" infection group (n = 341). There were no differences in A1C and oral antidiabetic drug classes between "past" (n = 111) and "never/remote" infection groups (n = 230). Compared with the non-eradication group (n = 99), the eradication group (n = 98) had significant within-group (-0.17 ± 0.80%, P = 0.036) and between-group (-0.23 ± 0.10%, P = 0.024) improvements in A1C. CONCLUSIONS: Diabetes patients with active H. pylori infection need higher glycemic treatment intensity to achieve comparable glycemia. Furthermore, H. pylori eradication decreases A1C, and thus improves glycemic control.

Unsaturated Fatty Acids Increase the Expression of Hepassocin through a Signal Transducer and Activator of Transcription 3-Dependent Pathway in HepG2 Cells.

Hepassocin (HPS) is a hepatokine that regulates hepatocyte proliferation. It is known that HPS plays an important role in the development of nonalcoholic fatty liver diseases (NAFLD). Fatty acids, such as oleic acid (OLA), exhibit the ability to activate the signal transducer and activator of transcription-3 (STAT3), and the binding site of STAT3 is found in the promoter region of HPS. However, the regulation of HPS by fatty acids is still obscure. To clarify the regulation of HPS, we detected the expression of HPS by western blots. In addition, a hepatic steatosis cell culture model was established by treatment of different fatty acids, including linoleic acid (LNA), oleic acid, palmitic acid, and stearic acid. The intracellular lipid accumulation was confirmed by oil red O staining. Blocking of STAT3 activity was achieved by the pretreatment of the STAT3 inhibitor, stattic. We found that activation of STAT3 by interleukin-6 (IL-6) was mediated in the regulation of HPS expression. Treatment of unsaturated fatty acids significantly induced intracellular lipid accumulation in HepG2 cells. Moreover, the expressions of HPS were increased in unsaturated fatty acid-treated HepG2 cells, as compared with saturated fatty acid-treated groups. Also, the expression of HPS induced by OLA was blocked by the inhibition of STAT3 activity. Furthermore, we found that deletion of HPS by small interfering ribonucleic acid transfection decreased the protective effect of OLA on cell viability. Taken together, we provided evidence that STAT3 plays an important role in the regulation of OLA-induced HPS expression and the increased HPS may further participate in the development of NAFLD. In addition, the increase of HPS might be involved in the protective effect of OLA on cell viability.

The Hepatic Protection Effects of Hepassocin in Hyperglycemic Crisis.

Context: High glucose generates reactive oxygen species (ROS) and contributes to glucotoxicity in hepatocytes, and hyperglycemia causes structural and functional damage to the liver. However, only a mild hepatic dysfunction was observed in subjects with hyperglycemic crisis, implying a factor exists to exert a hepatic protective effect. Hepassocin is a hepatokine that modulates the proliferation and metabolism of hepatocytes and also exerts protective activity in liver injury. However, its role in hyperglycemic crisis-induced hepatic dysfunction remains unknown. Objective: To investigate the possible hepatic protection effects of hepassocin in hyperglycemic crisis. Design, Setting, and Patients: Plasma hepassocin concentrations and routine biochemistry were measured in 21 patients with hyperglycemic crisis before and after standard treatments. The effects of hepassocin on hepatic functions were evaluated in streptozotocin-induced hyperglycemic mice (STZ mice). HepG2 cells were used to clarify the possible mechanisms regulating hepassocin expression. Results: Plasma hepassocin concentrations decreased significantly in subjects with hyperglycemic crisis after standard treatment accompanied by improved hepatic functions. Correction of hyperglycemia in STZ mice also decreased the hepatic hepassocin expression. Injection of recombinant hepassocin improved hepatic functions and histologic changes and increased the expression of antioxidative stress proteins, including superoxide dismutase 1 (SOD1). In HepG2 cells, high glucose increased hepassocin expression through signal transducer and activator of transcription 3 and hepatocyte nuclear factor-related pathways. We also demonstrated that hepassocin increased SOD1 expression through an extracellular signal-regulated kinase 1/2 nuclear factor erythroid-2-related factor 2 pathway, decreasing ethyl acetate-induced ROS production and improving cell viability. Conclusions: Increased hepassocin secretion in hyperglycemic crisis might offset the deleterious effects of hyperglycemia on hepatocytes.

Fenretinide inhibits macrophage inflammatory mediators and controls hypertension in spontaneously hypertensive rats via the peroxisome proliferator-activated receptor gamma pathway.

Fenretinide is a novel anticancer agent reported to exhibit anti-invasive and antimetastatic activities. It has also been shown to improve obesity and diabetes, although the effects of fenretinide on hypertension are still unknown, and the detailed mechanisms remain unclear. In this study, we have shown that treatment with lipopolysaccharide (LPS) decreased the expression of peroxisome proliferator-activated receptor γ (PPARγ) in RAW264.7 macrophages, and pretreatment with fenretinide reversed the effect of LPS on PPARγ expression. In addition, LPS-induced pro-inflammatory cytokine production, including tumor necrosis factor-α, interleukin 6, and monocyte chemoattractant protein 1 were dose-dependently reversed by fenretinide, and the effects of fenretinide on LPS-induced pro-inflammatory cytokine production were blocked by treatment with PPARγ antagonist. Moreover, fenretinide decreased LPS-induced inducible nitric oxide synthase expression and nitrogen oxide production. These effects were blocked by the pretreatment with PPARγ antagonist in a dose-dependent manner, indicating fenretinide activated PPARγ to exert anti-inflammation activity. In view of the role of inflammation in hypertension and the anti-inflammatory action of fenretinide, we found that administration of fenretinide in spontaneously hypertensive rats significantly decreased blood pressure. Taken together, these results indicate that fenretinide might be a potent antihypertensive agent that works by suppressing inflammation via activating PPARγ.

A novel hepatokine, HFREP1, plays a crucial role in the development of insulin resistance and type 2 diabetes.

AIMS/HYPOTHESIS: Type 2 diabetes is highly correlated with nonalcoholic fatty liver disease (NAFLD). Hepatocyte-derived fibrinogen-related protein 1 (HFREP1) is a hepatokine that mediates NAFLD development; however, the role of HFREP1 in the development of insulin resistance and diabetes remains obscure. METHODS: A total of 193 age- and sex-matched participants with normal glucose tolerance, impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and newly diagnosed diabetes (NDD) were recruited for a cross-sectional study. Plasma HFREP1 levels were measured and multivariate linear regression analysis was used to evaluate the relationship between HFREP1, IFG, IGT and NDD. The causal relationship between HFREP1 and insulin resistance was then investigated in animal and cell models. Glucose and insulin tolerance tests, and euglycaemic-hyperinsulinaemic clamp, were used to evaluate insulin sensitivity in animals with Hfrep1 overexpression or knockdown in liver by lentiviral vectors. HepG2 cells were used to clarify the possible mechanism of HFREP1-induced insulin resistance. RESULTS: Plasma HFREP1 concentrations were significantly increased in participants with IFG, IGT and NDD. HFREP1 concentrations were independently associated with fasting plasma glucose levels, insulin resistance, IFG, IGT and NDD. Injection of recombinant HFREP1 or Hfrep1 overexpression induced insulin resistance in mice, and HFREP1 disrupted insulin signalling to induce insulin resistance through an extracellular signal-regulated kinase (ERK)1/2-dependent pathway. Moreover, hepatic knockdown of HFREP1 improved insulin resistance in both mice fed a high-fat diet and ob/ob mice. CONCLUSIONS/INTERPRETATION: These findings highlight the crucial role of HFREP1 in insulin resistance and diabetes, and provide a potential strategy and biomarker for developing therapeutic approaches to combat these diseases.

Cardiotrophin-1 is inversely associated with obesity in non-diabetic individuals.

Cardiotrophin-1 is known to be a key regulator of energy homeostasis, as well as glucose and lipid metabolism in vivo. However, there are inconsistent results of the association between cardiotrophin-1 and obesity in humans, possibly confounded by hyperglycemia. Therefore, the aim of this study was to investigate the relationships among cardiotrophin-1 levels, overweight and obese individuals without diabetes in a Chinese population. The median (inter-quarter range) serum cardiotrophin-1 levels were 447.9 (230.9, 913.9), 350.6 (201.1, 666.5), and 288.1 (162.3, 572.4) pg/ml in non-diabetic subjects who were of normal weight (n = 522), overweight (n = 203), and obese (n = 93), respectively (trend test p < 0.001). Subjects who were overweight and obese had significantly lower cardiotrophin-1 levels than those with normal weight. The multivariate linear regression analyses showed that overweight (beta = -338.718, 95% CI = -552.786 ~ -124.651, p < 0.01), obese (beta = -530.275, 95% CI = -832.967 ~ -227.583, p < 0.01), and smoking (beta = -377.375, 95% CI = -654.353 ~ -100.397, p < 0.01) were negatively related to cardiotrophin-1 after adjusting for age, gender, HOMA-IR, hypertension, total cholesterol, HDL, triglyceride, eGFR, ALT, and alcohol drinking. The results of this study provided epidemiological evidence that non-diabetic subjects who were overweight or obesity had significantly lower cardiotrophin-1 concentrations than those with normal weight, and both obesity and being overweight were inversely associated with cardiotrophin-1 levels.

Both diabetes and fetuin-A are independently associated with increased risk of arterial stiffness.

BACKGROUND: Arterial stiffness is a functional assessment of vascular damage caused by cardiovascular disease (CVD) risk factors. Fetuin-A is associated with subclinical CVD and incident or fatal CVD, with some modification of its effect occurring with the presence of diabetes. We investigated the impact of different glycemic statuses and serum fetuin-A levels on arterial stiffness. METHODS: A total of 312 age- and sex-matched subjects with normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and newly diagnosed diabetes (NDD) were recruited. Serum fetuin-A levels were measured, and arterial stiffness was assessed by brachial-ankle pulse-wave velocity (baPWV). RESULTS: We found that the mean values of baPWV were 1533±338, 1518±353, 1589±307, and 1690±414 cm/s, and fetuin-A levels were 298±69, 313±67, 330±86, and 342±93 µg/ml, in subjects with NGT, IFG, IGT, and NDD, respectively (both p<0.001, test for trend). NDD subjects had significantly higher baPWV and fetuin-A levels than those with NGT. Multiple linear regression analysis showed that age, fetuin-A, diabetes, hypertension, and hypertriglyceridemia are independently associated factors of baPWV after adjusting for cardiometabolic risk factors, HOMA-IR, and adiponectin. CONCLUSION: Both diabetes and fetuin-A levels are independently associated with arterial stiffness. Fetuin-A may further aggravate increased arterial stiffness in diabetes.

Cardiotrophin-1 is associated with increased risk of arterial stiffness.

AIM: Cardiotrophin-1 null mice presented decreased arterial stiffness. The aim of this study is to investigate the relationship between cardiotrophin-1 and arterial stiffness, assessed by brachial-ankle pulse-wave velocity (baPWV). METHODS: We enrolled 300 subjects, 200 with baPWV >1400 and 100 with baPWV ≤1400 cm/s. RESULTS: Cardiotrophin-1 levels were significantly higher in subjects with baPWV >1400 than those with baPWV ≤1400 cm/s. The multivariate logistic regression analysis showed that age, prehypertension, hypertension and cardiotrophin-1 were independently associated with baPWV >1400 cm/s after adjusting for gender, obesity, diabetes, homeostasis model assessment-insulin resistance, total cholesterol, high-density lipoprotein cholesterol, triglyceride, high-sensitivity C-reactive protein, creatinine, smoking and habitual exercise. CONCLUSION: Cardiotrophin-1 is positively related to baPWV independent of traditional cardiometabolic risk factors for arterial stiffness.

Activation of free fatty acid receptor 1 improves hepatic steatosis through a p38-dependent pathway.

Hepatic steatosis is highly correlated with insulin resistance and diabetes. Although, it has been demonstrated that activation of free fatty acid receptor 1 (FFAR1) by agonists showed benefits for the improvement of diabetes, the effects of FFAR1 agonists on hepatic steatosis were unknown. In this study, a high fat diet (HFD)-induced hepatic steatosis animal model was utilized to evaluate the effects of an FFAR1 agonist, GW9508, on hepatic lipid accumulation, and HepG2 hepatoma cells were also used to clarify the possible mechanisms. Administration of GW9508 significantly decreased the hepatic lipid accumulation with decreased expressions of lipogenesis-related proteins in HFD mice. Knockdown of hepatic Ffar1 by lentiviral vectors containing short hairpin RNA targeted to Ffar1 diminished the effect of GW9508 in HFD mice. In addition, GW9508 decreased oleic acid-induced lipid accumulation in HepG2 cells by decreases in the expression of lipogenesis-related proteins. Moreover, GW9508 downregulated the expression of sterol regulatory element-binding protein 1 (SREBP1) through a p38-dependent pathway, whereas knockdown of Ffar1 in HepG2 cells diminished the effect of GW9508 on the decrease in SREBP1. Considering all these results together, GW9508 exerts a therapeutic effect to improve hepatic steatosis through a p38-dependent pathway. Thus, investigation of chemicals that act on FFAR1 might be a new strategy for the treatment of hepatic steatosis.