Risk-adapted moderate hypofractionation of prostate cancer : A prospective analysis of acute toxicity, QOL and outcome in 221 patients.

PURPOSE: Prostate cancer (PCA) is highly heterogeneous in terms of its oncologic outcome. We therefore aimed to tailor radiation treatment to the risk status by using three different hypofractionated radiation regimen differing in applied dose, use of rectum spacer, inclusion of pelvic lymph nodes (pLN) and use of androgen deprivation therapy (ADT). Here we report on acute toxicity, quality of life (QOL) and oncologic outcome at a median follow-up of 12 months. METHODS: A total of 221 consecutive PCA patients received hypofractionated intensity-modulated radiotherapy (IMRT). Low-risk (LR) patients were planned to receive 60 Gy in 20 fractions (EQD2α/ß1.5 = 77.1 Gy), intermediate-risk (IR) patients 63 Gy in 21 fractions (EQD2α/ß1.5 = 81 Gy), and high-risk (HR) patients 67.5 Gy in 25 fractions (EQD2α/ß1.5 = 81 Gy) to the prostate and 50 Gy in 25 fractions to the pLN. Acute rectal toxicity was assessed by endoscopy. In addition, toxicity was scored using CTC-AE 4.0 and IPSS score, while QOL was assessed using QLQ-PR25 questionnaires. RESULTS: Acute CTC reactions were slightly higher in the HR regimen but reverted to baseline at 3 months. GI G2 toxicity was 4%, 0% and 12% for the LR, IR and HR regimen. Compared to IR patients, the increase in toxicity in HR patients was statistically significant (p = 0.002) and mainly caused by a higher incidence of diarrhea presumably due to pelvic EBRT. QOL scores of all domains were worse for the HR regimen (not significant). CONCLUSION: Risk-adapted moderate hypofractionation is associated with low GI/GU toxicity. Given the higher rate of pelvic metastases in HR patients, slightly higher transient acute reactions should be outweighed by possible oncological benefits.

Alpha-syntrophin deficient mice are protected from adipocyte hypertrophy and ectopic triglyceride deposition in obesity.

Alpha-syntrophin (SNTA) is a molecular adapter protein which is expressed in adipocytes. Knock-down of SNTA in 3T3-L1 preadipocytes increases cell proliferation, and differentiated adipocytes display small lipid droplets. These effects are both characteristics of healthy adipose tissue growth which is associated with metabolic improvements in obesity. To evaluate a role of SNTA in adipose tissue morphology and obesity associated metabolic dysfunction, SNTA deficient mice were fed a standard chow or a high fat diet. Mice deficient of SNTA had less fat mass and smaller adipocytes in obesity when compared to control animals. Accordingly, these animals did not develop liver steatosis and did not store excess triglycerides in skeletal muscle upon high fat diet feeding. SNTA-/- animals were protected from hyperinsulinemia and hepatic insulin resistance. Of note, body-weight, food uptake, and serum lipids were normal in the SNTA null mice. SNTA was induced in adipose tissues but not in the liver of diet induced obese and ob/ob mice. In human subcutaneous and visceral fat of seven patients SNTA was similarly expressed and was not associated with body mass index. Current data demonstrate beneficial effects of SNTA deficiency in obesity which is partly attributed to smaller adipocytes and reduced white adipose tissue mass. Higher SNTA protein in fat depots of obese mice may contribute to adipose tissue hypertrophy and ectopic lipid deposition which has to be confirmed in humans.

C1q/TNF-related protein-3 (CTRP-3) attenuates lipopolysaccharide (LPS)-induced systemic inflammation and adipose tissue Erk-1/-2 phosphorylation in mice in vivo.

BACKGROUND: The C1q/TNF-related proteins comprise a growing family of adiponectin paralogous proteins. CTRP-3 represents a novel adipokine with strong expression in adipose tissue and was shown to inhibit chemokine and cytokine release in adipocytes and monocytes in vitro. The aim of the study was to gain the proof of principle that CTRP-3 is a potent anti-inflammatory adipokine in vivo. METHODS: C57BL/6N mice were treated intraperitoneally (i.p.) with bacterial lipopolysaccharide (LPS) for 2h. The effects of a 30 min pre-treatment with CTRP-3 i.p. or intravenously (i.v.) on systemic and on epididymal, perirenal and subcutaneous adipose tissue inflammation was analyzed via real-time RT-PCR, ELISA and Western blot analysis. RESULTS: LPS (1 µg i.p.) significantly increased serum IL-6 and MIP-2 levels as well as epididymal adipose tissue expression of IL-6 and MIP-2 in mice, whereas CTRP-3 (10 µg i.p.) alone or PBS (i.p.) had no effect. Pre-treatment of mice by CTRP-3 i.p. prior to LPS application significantly attenuated LPS-induced cytokine levels but had no effect on adipose tissue cytokine mRNA expression. In contrast to i.p. application of CTRP-3, systemic i.v. application was not sufficient to inhibit LPS-induced cytokine levels or mRNA tissue expression. CTRP-3 given i.p. significantly attenuated LPS-induced phosphorylation of Erk-1/-2 in inguinal adipose tissue. CONCLUSION: The present study shows the proof of principle that the novel adipokine CTRP-3 is a potent inhibitor of LPS-induced systemic inflammation and LPS-induced signaling in adipose tissue in vivo.

Chemerin is highly expressed in hepatocytes and is induced in non-alcoholic steatohepatitis liver.

Chemerin is a recently described adipokine whose adipose tissue and serum levels are increased in obesity. Chemerin is expressed in the liver, and here, expression of chemerin has been studied in liver cells and in non-alcoholic fatty liver disease (NAFLD) which is more often found in obesity. Chemerin is shown to be highly expressed in primary human hepatocytes (PHH) whereas hepatic stellate cells (HSC) produce only low levels of this protein. In mice fed a high fat diet hepatic chemerin mRNA but not protein is increased. Chemerin protein is comparably expressed in the liver of control animals and ob/ob mice. Rodents fed a Paigen diet or methionine-choline deficient diet (MCD) develop non-alcoholic steatohepatitis (NASH), and liver chemerin protein tends to be higher in the first and is significantly increased in the latter. Of note, MCD fed mice have similar serum chemerin levels as the respective control animals despite lower body weight. In human fatty liver and NASH liver chemerin mRNA also tends to be induced. Cytokines like TNF and adipokines with an established role in NASH do not considerably affect PHH chemerin protein. The antidiabetic drug metformin reduces cellular and soluble chemerin in PHH as has already been described in adipose tissue. In conclusion current data show that primary human hepatocytes are a major source of hepatic chemerin and increased liver chemerin in NASH may even contribute to systemic levels.

Adipocyte chemerin release is induced by insulin without being translated to higher levels in vivo.

BACKGROUND: Chemerin is an adipokine that regulates insulin sensitivity and insulin secretion. Prolonged hyperinsulinaemia is associated with higher systemic chemerin, and insulin induces adipose tissue chemerin release. These findings led us to hypothesize that systemic chemerin may be associated with post-prandial glucose metabolism and/or may even be induced after oral glucose load. Therefore, the effect of insulin on adipocyte chemerin levels and systemic chemerin in mice was analysed. Further, systemic levels of chemerin after oral glucose load in nondiabetic individuals were studied. DESIGN AND METHODS: Chemerin levels were determined in adipocytes after short-term and long-term treatment with insulin. Effects of acute hyperinsulinaemia were studied in mice. Chemerin was measured during oral glucose tolerance test in 66 healthy, nondiabetic individuals stratified for established body mass index categories. RESULTS: Insulin induces chemerin release from adipocytes within 24 h, while cellular levels are not affected. Short-term hyperinsulinaemia also upregulates adipocyte chemerin in vitro but has no effect on adipose tissue and chemerin serum levels of mice. Systemic chemerin is higher in overweight/obese than normal-weight controls and positively correlates with total cholesterol. Chemerin is not associated with markers of insulin sensitivity like fasting glucose or insulin. Fasting chemerin levels are similar to concentrations measured 1 and 2 h after oral glucose uptake in overweight and obese donors. CONCLUSIONS: Post-prandial hyperinsulinaemia does not contribute to higher chemerin levels in nondiabetic individuals.

Admission levels of soluble CD137 are increased in patients with acute pancreatitis and are associated with subsequent complications.

The progression of acute pancreatitis to necrotizing pancreatitis which often results in high morbidity and mortality is difficult to predict. Here we report that serum concentrations of sCD137 are increased in patients with acute pancreatitis. Admission levels and 10-day median sCD137 levels positively correlate with markers of biliary pancreatitis and the 10-day sCD137 median is significantly higher in metabolic than in alcoholic pancreatitis. Serum concentrations of sCD137 at time of admission and the 10-day median of sCD137 correlate with the Ranson and APACHE II disease scores but not with the radiological Balthazar and Schroeder scores that reflect pancreatic and peripancreatic necrosis. Further, sCD137 levels correlate with the probability of complications and lethality. The association of sCD137, a product of activated T cells, with the severity of acute pancreatitis suggests that T cells contribute to the pathogenesis of acute pancreatitis.

Admission visfatin levels predict pancreatic and peripancreatic necrosis in acute pancreatitis and correlate with clinical severity.

OBJECTIVES: Adipocytes of peripancreatic and intrapancreatic adipose tissue secret adipocytokines such as leptin, adiponectin, and resistin. For resistin, a role as an early predictor of peripancreatic necrosis and clinical severity in acute pancreatitis has been reported. It was the aim of this study to investigate whether the adipocytokine visfatin is able to serve as an early marker predicting peripancreatic necrosis and clinical severity. METHODS: A total of 50 patients (20 females and 30 males) with acute pancreatitis were included in this noninterventional, prospective, and monocentric cohort study on diagnostic accuracy. Clinical severity was classified by the Ranson score and APACHE-II (Acute Physiology and Chronic Health Evaluation II) score. Pancreatic and peripancreatic necrosis were quantified by the computed tomography-based Balthazar score, the Schroeder score, and the pancreatic necrosis score. Visfatin was measured at admission and daily for 10 days by enzyme-linked immunosorbent assay (ELISA). RESULTS: Visfatin values were significantly and positively correlated with clinical severity (APACHE-II score and Ranson score) and with clinical end points such as death and need for interventions. Admission visfatin levels were significantly elevated in patients with higher pancreatic and extrapancreatic necrosis scores. It was shown by receiver operator characteristics that admission visfatin concentration provides a positive predictive value of 93.3% in predicting the extent of peripancreatic necrosis (area under the curve (AUC): 0.89, P<0.001, sensitivity: 93.3%, specificity: 81.8%, likelihood ratio: 5.1, post-test probability: 93%) by using a cutoff value of 1.8 ng/ml. CONCLUSIONS: Admission visfatin concentration serves as an early predictive marker of peripancreatic necrosis and clinical severity in acute pancreatitis. Visfatin may have potential for clinical use as a new and diagnostic serum marker.

Adiponectin stimulates release of CCL2, -3, -4 and -5 while the surface abundance of CCR2 and -5 is simultaneously reduced in primary human monocytes.

The adipokine adiponectin is well known to affect the function of immune cells and upregulation of CCL2 by adiponectin in monocytes/macrophages has already been reported. In the current study the effect of adiponectin on CCL2, -3, -4, and -5 and their corresponding receptors CCR1, CCR2, and CCR5 has been analyzed. Adiponectin elevates mRNA and protein of the CC chemokines in primary human monocytes. Simultaneously the surface abundance of CCR2 and CCR5 is reduced while CCR1 is not affected. Downregulation of CCR2 by adiponectin is blocked by a CCR2 antagonist although expression of the CCL2 regulated genes CCR2 and TGF-beta 1 is not altered in the adiponectin-incubated monocytes. CCL2, -3, and -5 concentrations measured in supernatants of monocytes of normal-weight (NW), overweight (OW), and type 2 diabetic (T2D) patients positively correlate with BMI and are increased in obesity and T2D. In contrast CCL4 is similarly abundant in the supernatants of all of these monocytes. The degree of adiponectin-mediated induction of the chemokines CCL3, -4, and -5 negatively correlates with their basal levels and upregulation of CCL3 and CCL5 is significantly impaired in OW and T2D cells. Serum concentrations of these chemokines are almost equal in the three groups and do not correlate with the levels in monocyte supernatants. In conclusion these data demonstrate that adiponectin stimulates release of CCL2 to CCL5 in primary human monocytes, and induction in cells of overweight probands is partly impaired. Adiponectin also lowers surface abundance of CCR2 and CCR5 and downregulation of CCR2 seems to depend on autocrine/paracrine effects of CCL2.

Elevated free fatty acids and impaired adiponectin bioactivity contribute to reduced SOD2 protein in monocytes of type 2 diabetes patients.

Type 2 diabetes (T2D) is characterized by increased oxidative stress contributing to the development of cardiovascular disease (CVD). Monocytes are critically important in the pathogenesis of CVD and antioxidant enzymes like superoxide dismutase (SOD2) protect these cells from excessive reactive oxygen species (ROS). Adiponectin is an adipocyte-derived protein with atheroprotective function and the effect of adiponectin on monocyte SOD2 was analyzed herein. Adiponectin upregulated SOD2 mRNA and dose- and time-dependently induced SOD2 protein in primary human monocytes. Elevated systemic free fatty acids (FFA) are commonly found in T2D patients and palmitic acid as well as oleic acid reduced monocyte SOD2 protein. Adiponectin mediated upregulation of SOD2, however, was not affected by FFA incubation. SOD2 protein was reduced in T2D monocytes compared to monocytes of age- and body mass index-matched healthy controls. Adiponectin still induced SOD2 in T2D monocytes but efficiency tended to be reduced. In summary this study indicates that elevated systemic free fatty acids and impaired adiponectin activity contribute to reduced SOD2 and most likely increased oxidative stress in T2D monocytes.

Admission resistin levels predict peripancreatic necrosis and clinical severity in acute pancreatitis.

OBJECTIVES: Peripancreatic necrosis determines clinical severity in acute pancreatitis. Early markers predicting peripancreatic necrosis and clinical severity are lacking. Because adipocytes of peripancreatic adipose tissue secret highly active adipocytokines, the aim of the study was to investigate whether adipocytokines are able to serve as early markers predicting peripancreatic necrosis and clinical severity. METHODS: A total of 50 patients (20 women, 30 men) with acute pancreatitis were included in this noninterventional, prospective, and monocentric cohort study on diagnostic accuracy. Clinical severity was classified by the Ranson score and the APACHE (Acute Physiology And Chronic Health Evaluation) II score. Pancreatic and peripancreatic necrosis were quantified by using the computed tomography-based Balthazar score, the Schroeder score, and the pancreatic necrosis score. Adiponectin, leptin, and resistin were measured at admission and daily for at least 10 days by enzyme-linked immunosorbent assay. RESULTS: In contrast to admission C-reactive protein values, admission resistin values were significantly correlated with clinical severity and even with clinical end points such as death and need for interventions. Admission resistin levels were significantly elevated in patients with higher pancreatic and extrapancreatic necrosis scores. It was shown by receiver-operator characteristics that admission resistin concentration provides a positive predictive value of 89% in predicting the extent of peripancreatic necrosis (area under the curve, 0.8; P=0.002; sensitivity, 80%; specificity, 70%) by using a cutoff value of 11.9 ng/ml. CONCLUSIONS: Admission resistin concentration serves as an early predictive marker of peripancreatic necrosis and clinical severity in acute pancreatitis. Resistin may have potential for clinical use as a new and diagnostic serum marker.

Effects of the new adiponectin paralogous protein CTRP-3 and of LPS on cytokine release from monocytes of patients with type 2 diabetes mellitus.

AIMS/HYPOTHESIS: It was the aim to investigate the hypothesis that the new C1q/TNF-family member CTRP-3 (C1q/TNF-related protein-3) acts anti-inflammatory in human monocytes from healthy controls and patients with type 2 diabetes mellitus (T2D). METHODS: Monocytes were isolated from 20 healthy controls and 30 patients with T2D. IL-6 and TNF concentrations were measured by ELISA. CTRP-3 was expressed in insect cells and used for stimulation experiments. RESULTS: Basal IL-6 and TNF were not different in control and in T2D monocytes. LPS-stimulation (1 microg/ml) significantly (p<0.001) increased IL-6 and TNF in the supernatants of control and in T2D monocytes to a similar extent. CTRP-3 (1 microg/ml) significantly (p=0.03) inhibited LPS-induced IL-6 in control monocytes but not in T2D monocytes. TNF upon co-stimulation with LPS and CTRP-3 was significantly (p=0.012) lower in control than in T2D monocytes. LPS-induced TNF concentration was significantly and positively correlated with serum total cholesterol and LDL cholesterol in T2D patients. CONCLUSIONS: CTRP-3 inhibits LPS-induced IL-6 and TNF release. This anti-inflammatory effect is lost in T2D. Serum cholesterol concentration affects the pro-inflammatory potential of LPS to induce TNF release from T2D monocytes in the presence or absence of CTRP-3. CTRP-3 might partly account for the pro-inflammatory state in T2D.

Mapping and DNA sequence characterisation of the Rysto locus conferring extreme virus resistance to potato cultivar 'White Lady'.

Virus resistance genes carried by wild plant species are valuable resources for plant breeding. The Rysto gene, conferring a broad spectrum of durable resistance, originated from Solanum stoloniferum and was introgressed into several commercial potato cultivars, including 'White Lady', by classical breeding. Rysto was mapped to chromosome XII in potato, and markers used for marker-assisted selection in breeding programmes were identified. Nevertheless, there was no information on the identity of the Rysto gene. To begin to reveal the identification of Rysto, fine-scale genetic mapping was performed which, in combination with chromosome walking, narrowed down the locus of the gene to approximately 1 Mb. DNA sequence analysis of the locus identified six full-length NBS-LRR-type (short NLR-type) putative resistance genes. Two of them, designated TMV2 and TMV3, were similar to a TMV resistance gene isolated from tobacco and to Y-1, which co-segregates with Ryadg, the extreme virus resistance gene originated from Solanum andigena and localised to chromosome XI. Furthermore, TMV2 of 'White Lady' was found to be 95% identical at the genomic sequence level with the recently isolated Rysto gene of the potato cultivar 'Alicja'. In addition to the markers identified earlier, this work generated five tightly linked new markers which can serve potato breeding efforts for extreme virus resistance.

The Effect of Biochemical Remission on Bone Metabolism in Cushing's Syndrome: A 2-Year Follow-Up Study.

Endogenous Cushing's syndrome (CS) is a rare cause of secondary osteoporosis. The long-term consequences for bone metabolism after successful surgical treatment remain largely unknown. We assessed bone mineral density and fracture rates in 89 patients with confirmed Cushing's syndrome at the time of diagnosis and 2 years after successful tumor resection. We determined five bone turnover markers at the time of diagnosis, 1 and 2 years postoperatively. The bone turnover markers osteocalcin, intact procollagen-IN-propeptide (PINP), alkaline bone phosphatase, CTX-I, and TrAcP 5b were measured in plasma or serum by chemiluminescent immunoassays. For comparison, 71 sex-, age-, and body mass index (BMI)-matched patients in whom Cushing's syndrome had been excluded were studied. None of the patients received specific osteoanabolic treatment. At time of diagnosis, 69% of the patients had low bone mass (mean T-score = -1.4 ± 1.1). Two years after successful surgery, the T-score had improved in 78% of patients (mean T-score 2 years postoperatively -1.0 ± 0.9). The bone formation markers osteocalcin and intact PINP were significantly decreased at time of diagnosis (p ≤ 0.001 and p = 0.03, respectively), and the bone resorption marker CTX-I and TrAcP 5b increased. Postoperatively, the bone formation markers showed a three- to fourfold increase 1 year postoperatively, with a moderate decline thereafter. The bone resorption markers showed a similar but less pronounced course. This study shows that the phase immediately after surgical remission from endogenous CS is characterized by a high rate of bone turnover resulting in a striking net increase in bone mineral density in the majority of patients. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.

Fatty acid-induced induction of Toll-like receptor-4/nuclear factor-kappaB pathway in adipocytes links nutritional signalling with innate immunity.

To study the effects of fatty acids and the involvement of the Toll-like receptor-4/nuclear factor-kappaB (TLR-4/NF-kappaB) pathway with respect to the secretion of adipokines from adipocytes 3T3-L1 adipocytes were stimulated with increasing doses of fatty acids. The secretion of adiponectin, resistin and monocyte chemoattractant protein-1 (MCP-1) was measured by enzyme-linked immunosorbent assay. The NF-kappaB p65 nuclear translocation and TLR-4 expression were investigated by Western blot. The effects mediated by NF-kappaB were tested using a specific NF-kappaB-inhibitor and TLR-4-induced effects were analysed with a neutralizing TLR-4 antibody. Binding of (14)C-labelled fatty acids to TLR-4/MD-2 was investigated using a FLAG-tagged extracellular part of TLR-4 fused to full-length MD-2 via a linker (lipopolysaccharide-Trap). The messenger RNA (mRNA) expression of adipokines in abdominal adipose tissue of rats fed a standard chow or a high-fat diet was investigated by reverse transcription-polymerase chain reaction. The TLR-4 is induced during adipocyte differentiation and its expression is enhanced following fatty acid stimulation. The stimulatory effects of stearic and palmitic acids on MCP-1 secretion and of palmitoleic acid on resistin secretion are mediated via NF-kappaB. The stimulatory effects of stearic, palmitic and palmitoleic acids on resistin secretion and the stimulatory effect of stearic acid on MCP-1 secretion are mediated via TLR-4. Fatty acid-mediated effects are caused by an endogenous ligand because fatty acids were shown not to bind directly to TLR-4/MD-2. Adipose tissue mRNA expression and serum levels of adipokines did not differ in rats fed a high-fat diet. These data provide a new molecular mechanism by which fatty acids can link nutrition with innate immunity.

Toward a Diagnostic Score in Cushing's Syndrome.

Cushing's syndrome (CS) is a classical rare disease: it is often suspected in patients who do not have the disease; at the same time, it takes a mean of 3 years to diagnose CS in affected individuals. The main reason is the extreme rarity (1-3/million/year) in combination with the lack of a single lead symptom. CS has to be suspected when a combination of signs and symptoms is present, which together make up the characteristic phenotype of cortisol excess. Unusual fat distribution affecting the face, neck, and trunk; skin changes including plethora, acne, hirsutism, livid striae, and easy bruising; and signs of protein catabolism such as thinned and vulnerable skin, osteoporotic fractures, and proximal myopathy indicate the need for biochemical screening for CS. In contrast, common symptoms like hypertension, weight gain, or diabetes also occur quite frequently in the general population and per se do not justify biochemical testing. First-line screening tests include urinary free cortisol excretion, dexamethasone suppression testing, and late-night salivary cortisol measurements. All three tests have overall reasonable sensitivity and specificity, and first-line testing should be selected on the basis of the physiologic conditions of the patient, drug intake, and available laboratory quality control measures. Two normal test results usually exclude the presence of CS. Other tests and laboratory parameters like the high-dose dexamethasone suppression test, plasma ACTH, the CRH test, and the bilateral inferior petrosal sinus sampling are not part of the initial biochemical screening. As a general rule, biochemical screening should only be performed if the pre-test probability for CS is reasonably high. This article provides an overview about the current standard in the diagnosis of CS starting with clinical scores and screenings, the clinical signs, relevant differential diagnoses, the first-line biochemical screening, and ending with a few exceptional cases.

Reduced response to adiponectin and lower abundance of adiponectin receptor proteins in type 2 diabetic monocytes.

The abundance of the adiponectin receptors, AdipoR1 and AdipoR2, and the effects of the antidiabetic adipokine adiponectin in monocytes of normal-weight and overweight controls and type 2 diabetic patients (T2D) were analyzed. AdipoR1 and AdipoR2 mRNAs were increased in monocytes of obese controls and T2D patients when compared to normal-weight controls, and AdipoR1 mRNA positively correlated to AdipoR2 mRNA, the waist to hip ratio and systemic adiponectin. However, AdipoR1 and AdipoR2 proteins were lower in monocytes of T2D compared to normal-weight donors. Induction of IL-6 and IL-8 by adiponectin, an effect involving p38 MAPK, was also reduced in T2D monocytes.

Lipopolysaccharide regulated protein expression is only partly impaired in monocytes from patients with type I diabetes.

BACKGROUND: Monocytes play an important role in innate immunity and atherosclerosis. A disturbed secretion of cytokines in lipopolysaccharide (LPS) activated monocytes from type 1 diabetes (T1D) patients has been described and may contribute to the impaired inflammatory response in these individuals. In the present study the influence of LPS on five different proteins with a function in immunity and atherosclerosis was analyzed in monocytes from controls and T1D patients. METHODS: Monocytes were isolated from controls and T1D patients and the LPS-stimulated increase of IL-6, CXCL8, monocyte chemotactic protein 1 (CCL2, MCP-1) and superoxide dismutase (SOD 2), as well as the LPS-mediated decrease of apolipoprotein E (Apo E) in primary human monocytes from controls and T1D patients was determined. RESULTS: CCL2 and IL-6 secretion in response to LPS was found significantly reduced in monocytes from T1D patients when compared to controls whereas basal CCL2 release was similar in control and T1D cells. In contrast, CXCL8 and apolipoprotein E secretion and SOD 2 expression upon LPS stimulation is similar from T1D and control monocytes. CONCLUSION: These data indicate that LPS-mediated protein expression is only partly disturbed in monocytes from T1D patients. Reduced secretion of IL-6 and CCL2 in activated monocytes of these patients may contribute to an impaired inflammatory response and vascular disease.

In vivo suppression of visfatin by oral glucose uptake: evidence for a novel incretin-like effect by glucagon-like peptide-1 (GLP-1).

BACKGROUND: Visfatin represents an adipokine of the visceral adipose tissue exerting pleiotropic effects. The aim of the study was to characterize the physiological regulation of visfatin release in vivo in healthy, nondiabetic probands and in adipocytes in vitro. SUBJECTS AND METHODS: One hundred healthy subjects (64 females and 36 males) underwent an oral glucose tolerance test (75 g). Probands were characterized by anthropometric and laboratory parameters. Fasting and postprandial (1 and 2 h) serum concentrations of glucose, insulin, and visfatin were measured. Stimulation experiments using glucose, insulin, mannitol, and glucagon-like peptide-1 (GLP-1) were performed on 3T3-L1 adipocytes including Western blot analysis. RESULTS: Fasting visfatin levels were not different between males/females or lean/obese individuals but were negatively (r = -0.5; P < 0.001) correlated with fasting glucose levels. Visfatin levels were rapidly and significantly suppressed (P < 0.001) upon an oral glucose intake, and this suppression was more pronounced in overweight and female probands. In vitro experiments demonstrated that hyperglycemia, osmotic stress, and sex steroids did not influence visfatin release. In contrast, insulin strongly (P = 0.002) inhibited visfatin release in vitro by approximately 50%, and this suppression was more pronounced under hyperglycemia. Importantly, GLP-1 strongly (P < 0.001) inhibited adipocytic visfatin release by approximately 50%. CONCLUSIONS: Insulin and GLP-1 are responsible for the rapid suppression of visfatin levels upon an oral glucose uptake in healthy probands. The inhibitory effect of GLP-1 on adipocytic visfatin release together with the absence of direct glucose effects on visfatin release suggests the existence of a novel incretin-like effect represented by a GLP-1/visfatin/axis.

Systemic resistin is increased in type 2 diabetic patients treated with loop diuretics.

Increased serum resistin was found in rodent models of obesity and insulin resistance, whereas contradictory results have been obtained in human studies. In humans, resistin is primarily released by monocytes/macrophages, suggesting that soluble levels may be associated with macrophage activation. Here, systemic and monocyte-released resistin levels were found to be similar in type 2 diabetic (T2D) patients, overweight controls and normal-weight controls. When adjusted for body mass index and age, serum resistin modestly correlated with gamma-glutamyltransferase levels, fasting glucose and interleukin-6. Systemic resistin was marginally increased in T2D patients treated with beta-blockers or urate-lowering drugs and was considerably higher in patients treated with loop diuretics. Monocyte-released resistin was even reduced by the loop diuretic furosemide, excluding the possibility that this drug may directly stimulate resistin synthesis. In summary, the current data indicate that changes accompanying renal dysfunction but not obesity or type 2 diabetes are associated with increased serum resistin.

Intracellular survival of Staphylococcus aureus in adipocyte-like differentiated 3T3-L1 cells is glucose dependent and alters cytokine, chemokine, and adipokine secretion.

Although obesity and type 2 diabetes mellitus are associated with Gram-positive infections and a worse clinical outcome, it is unknown whether adipocytes can be infected by Gram-positive bacteria. Adipocyte-like differentiated 3T3-L1 cells and Staphylococcus aureus were used for infection experiments under normoglycemic (100 mg/dl) and hyperglycemic (450 mg/dl) conditions in the presence/absence of insulin (1 µm). Intracellular presence and survival of S. aureus was investigated quantitatively. Supernatant cytokines, chemokines, and adipokines were measured by ELISA. Lipid metabolism and cellular morphology of infected adipocytes were investigated by different techniques. The present study provides the proof of principle that adipocyte-like cells can be infected by S. aureus dose dependently for up to 5 d. Importantly, low bacterial inocula did not affect cell viability. Intracellular survival of S. aureus was glucose dependent but not insulin dependent, and insulin receptor expression and insulin receptor signaling were not altered. Infection increased macrophage chemoattractant protein-1, visfatin, and IL-6 secretion, whereas resistin and adiponectin were decreased. Infected adipocytes had higher intracellular triacylglycerol concentrations and larger lipid droplets because of a decreased lipolysis. Taken together, infection of adipocytes by S. aureus is glucose dependent, inhibits cellular lipolysis, and affects the secretion of immunomodulating adipokines differentially. Because cell viability is not affected during infection, adipose tissue might function as a host for chronic infection by bacteria-causing metabolic, proinflammatory, and prodiabetic disturbances.