bluuebunny/crossref_metadata_2025_split huggingface dataset:
1750-P: Effects of Melatonin on the Insulin Signaling and Inflammatory Pathway of Rats with Apical Periodontitis
Authors: SUMIDA DORIS H. 
Published: June 2020

Background: Apical periodontitis (PEA) is oral inflammation related to the increase of proinflammatory cytokines that may act locally and systemically. PEA in rats has been shown to cause insulin resistance (IR) and impaired insulin signal. Melatonin (MEL) is known to improve IR. We hypothesized that administration of MEL in PEA rats may prevent the IR found in these animals. Therefore, the aim of this study was to verify, in rats with PEA, the effects of MEL on: IR; the insulin and inflammatory pathways; TNF-α levels.
Methodology: Seventy-two Wistar rats (60 days of age) were distributed into: control (CN); CN+MEL (CNMEL); PEA; PEA+MEL (PEAMEL). PEAs were induced in the first and second upper and lower molars of the right side using a surgical drill. Following PEA induction, MEL (5 mg/kg) was administered orally (drinking water) for 60 days. At the end of treatment were analyzed: 1) HOMA-IR; 2) TNF-α levels; 3) phosphorylation status of pp185 tyrosine, Akt serine and IKKα/β in soleus (SM) and extensor digitorum longus (EDL) muscles. Statistical analysis was performed by analysis of variance (ANOVA) followed by Bonferroni test (p&lt;0.05).
Results: HOMA-IR and TNF-α were higher in the PEA group than in the other groups (HOMA-IR: CN: 2.49 ± 0.24; PEA: 3.57 ± 0.24; CNMEL: 2.17 ± 0.13; PEAMEL: 2.57 ± 0.09 - TNF-α: CN: 8.56 ± 0.84; PEA: 13.42 ± 0.86; CNMEL: 9.21 ± 0.83; PEAMEL: 8.62 ± 0.42). The phosphorylation status of pp185 tyrosine and Akt serine was lower in the PEA group compared to the CN group in SM. Administration of MEL in the PEAMEL group increased the phosphorylation of both proteins. No statistical differences in these parameters were observed between the groups in the EDL muscle. Higher IKKα/β phosphorylation was observed in the PEA group compared to the other groups in both tissues.
Conclusions: PEA promoted IR, increased TNF-α levels, impaired insulin signal in SM and inflammatory pathway activation in SM and EDL. Administration of MEL only prevented changes in insulin signal in MS.

Disclosure
D.H. Sumida: None.

Funding
Fundação de Amparo a Pesquisa do Estado de São Paulo (2018/23346-3, 2019/18589-7); São Paulo State University
1753-P: Insulin Sensitivity in Long-Lived Growth Hormone–Releasing Hormone Knockout Mice
Authors: ZHANG FANG , ICYUZ MERT , SUN LIOU 
Published: June 2020

Disruption of growth hormone releasing hormone results in extended longevity with increased insulin sensitivity in mice. Yet, less is known about tissue-specific insulin action and insulin signaling pathway in growth hormone releasing hormone knock-out mice (GHRH-/-). In this study, our hyperinsulinemic-euglycemic clamp data showed that glucose infusion rate to maintain euglycemia was dramatically elevated in GHRH-/- mice. Insulin-mediated hepatic glucose production was suppressed whereas glucose uptake in skeletal muscle and brown adipose tissue were significantly increased in GHRH-/- mice compared to WT littermates. Furthermore, growth hormone deficiency further enhanced insulin sensitivity in metabolically active tissues via activated PI3K-AKT and MAPK-ERK1/2 signaling cascades. Altered tissue-specific insulin response is likely to mediate the prolonged longevity and healthy-aging effects of growth hormone deficiency in mice.

Disclosure
F. Zhang: None. M. Icyuz: None. L. Sun: None.

Funding
National Institutes of Health (R01AG057734)
1755-P: Insulin-Mediated Glucose Disposal and Muscle Microvascular Recruitment Are Mutual Predictors in Humans
Authors: LOVE KAITLIN , JAHN LINDA , HARTLINE LEE , BARRETT EUGENE , LIU ZHENQI 
Published: June 2020

Insulin recruits muscle microvasculature to enhance insulin and nutrient delivery. Insulin resistance (IR) blunts this microvascular action. While metabolic and microvascular IR usually coexist, and phenotypic traits which foretell metabolic IR are well established, those which predict microvascular IR are unknown. To test whether metabolic IR and its associated traits predict microvascular IR, we performed euglycemic insulin clamps (1 mU/kg/min) in healthy lean (n= 57), healthy obese (n=15) and lean type 1 diabetes subjects (T1D) (n=25), and tested parametric correlations and a multivariate model ANOVA. We measured insulin-mediated whole body glucose disposal (M-value) and insulin-induced changes in muscle microvascular blood volume (ΔMBV) by contrast-enhanced ultrasound. Predictor variables included body mass index (BMI), total body weight (WT), percent body fat (BF), lean body mass, blood pressure, maximal rate of oxygen consumption (VO2max), and plasma levels of LDL cholesterol (LDL-C), HDL cholesterol, triglycerides (TG), fasting insulin (INS) and free fatty acids.
A total of 97 subjects were included (mean age 25.4±6.8, 47% women) in the analyses. Among all factors, only M-value (r=0.23, p=0.023) and VO2max (r=0.20, p=0.047) correlated with ΔMBV. Conversely, INS (r=-0.59, P≤0.001), BF (r=-0.54, p≤0.001), VO2max (r=0.5, p≤0.001), BMI (r=-0.40, p&lt;0.001), WT (r=-0.33, p=0.001), LDL-C (r=-0.26, p=0.009), TG (r=-0.25, p=0.012), as well as ΔMBV correlated with M-value. While both ΔMBV (p=0.045) and TG (p=0.037) independently predicted M-value, only M-value independently predicted ΔMBV (p=0.045).
In conclusion, both M-value and VO2max correlated with but only M-value independently predicted microvascular IR. This suggests that, while metabolic and microvascular IR are important predictors of one another, most phenotypic predictors of metabolic IR do not predict microvascular IR.

Disclosure
K. Love: None. L. Jahn: None. L. Hartline: None. E. Barrett: None. Z. Liu: None.

Funding
American Diabetes Association (1-17-ICST-059 to Z.L.); National Institutes of Health (1F32DK121431-01)
1757-P: Tyrosine Phosphorylation of Phospholipase C in Human Skeletal Muscle Insulin Resistance
Authors: ZHANG XIANGMIN , MESTAREEHI AKTHAM H. , SEYOUM BERHANE , YI ZHENGPING 
Published: June 2020

Insulin resistance in skeletal muscle is among the primary contributors to the development of type 2 diabetes (T2D), a leading cause of heart disease, stroke, etc. Over 26 million U.S. adults have T2D. Molecular mechanisms for skeletal muscle insulin resistance remain elusive, limiting strategies to prevent/treat T2D. Phospholipase C, gamma 1 (PLCG1, aka PLC-γ1) serves as a signal transducer of tyrosine kinases and regulates various downstream signaling pathways in vitro. PLCG1 has been shown to interact with insulin receptor (IR) via its pleckstrin homology domain and plays a significant role in insulin-stimulated glucose uptake in adipocytes. Moreover, phosphorylation of tyrosine residue 771 (pTyr771) of PLCG1 has been shown to regulate PLCG1 activity. However, no prior publication shows that PLCG1 pTyr771 is linked with insulin resistance and T2D. Previously, we observed that insulin-stimulated PLCG1 pTyr771 is impaired in skeletal muscle from subjects with T2D compared to lean controls. In the present work, we mutated Tyr771 of PLCG1 to phenylalanine, and observed reduced insulin-stimulated AKT and AS160 phosphorylation in primary human skeletal muscle cells derived from an insulin sensitive participant. To identify the upstream regulator of PLCG1, we carried out in vitro kinase assay by incubating PLCG1 with insulin receptor. PLCG1 was expressed and purified from E. coli. The insulin receptor (active cytoplasmic terminus) was expressed and purified from insect cells. After incubating PLCG1 with insulin receptor in vitro for 30 min in the presence of ATP, PLCG1 phosphorylation was determined by HPLC-ESI-MS/MS. The result demonstrated that insulin receptor phosphorylated Tyr771 of PLCG1. Western blotting using pTyr771 specific antibodies confirmed these findings.
In summary, these results suggest that reduced insulin-stimulated pTyr771 may contribute to the development of insulin resistance and T2D, and the insulin receptor is an upstream regulator of PLCG1 pTyr771.

Disclosure
X. Zhang: None. A.H. Mestareehi: None. B. Seyoum: None. Z. Yi: None.

Funding
American Diabetes Association (1-13-TS-27 to Z.Y.); National Institutes of Health (R01DK107666, R01DK081750 to Z.Y.), (T32HL120822 to A.H.M.); DOTS Scholars (to A.H.M., Z.Y.)
1758-P: Type 2 Diabetes–Associated Mood Disorders: Role of Insulin Resistance in Serotonergic Neurons
Authors: MARTIN HUGO , BULLICH SÉBASTIEN , DUCROCQ FABIEN , GRALAND MARION , OLIVRY CLARA , LAYE SOPHIE , GUIARD BRUNO , FIORAMONTI XAVIER 
Published: June 2020

Type-2 Diabetes mellitus (T2DM) is mainly characterized by insulin-resistance and often accompanied by comorbidities such as major depressive disorders (MDD). Indeed, patients with T2DM are twice more likely to suffer from MDD and clinical studies have shown that insulin resistance is positively correlated with the severity of depressive symptoms. In preclinical studies, we and others showed that mice fed a High Fat Diet (HFD) for 16 weeks display both hallmarks of T2DM including increased basal blood glucose level and impaired glucose tolerance and anxio-depressive-like behaviors. We also showed that the insulin-sensitizing agent metformin reverses HFD-induced impaired glucose homeostasis and emotional alterations. As the serotonergic (5-HT) system in the brain is one of the major neuronal networks involved in the pathophysiology of MDD, we hypothesized that insulin resistance at the level of 5-HT neurons contributes to the development of mood disorders in a context of T2DM. Using patch-clamp electrophysiology, we show that HFD feeding impairs the excitability of dorsal Raphe 5-HT neurons while this effect is reversed by metformin treatment. Our data also show that local application of insulin increases firing rate of 5-HT neurons in chow fed animals and this is consistent with our histochemical observations indicating that the dorsal Raphe is endowed with a high density of insulin positive cells. Additionally, preliminary data suggest that intranasal or intra-Raphe insulin injection decreases anxiety in the elevated plus maze test. Our current work aims at evaluating the intranasal and intra-Raphe insulin injection in mice lacking the insulin receptor specifically in 5-HT neurons on emotional behaviors. Altogether, this study suggests that insulin action onto dorsal Raphe 5-HT neurons is important to control emotional behaviors and that insulin-resistance in these neurons is critical in the development of T2DM-associated mood disorders.

Disclosure
H. Martin: None. S. Bullich: None. F. Ducrocq: None. M. Graland: None. C. Olivry: None. S. Laye: None. B. Guiard: None. X. Fioramonti: None.

Funding
Société Francophone du Diabète; INRAE-Région Nouvelle Aquitaine
1759-P: Prostaglandin PGE2 Receptor EP4 Signaling Deficiency in Microglia Reduces Weight Gain with Transient Glucose Improvements in Diet-Induced Obesity
Authors: NIRAULA ANZELA , FASNACHT RACHAEL , NESS KELLY M. , FREY JEREMY , DORFMAN MAURICIO D. , THALER JOSHUA 
Published: June 2020

High fat diet (HFD) triggers a microglial inflammatory response in the mediobasal hypothalamus that is associated with weight gain and glucose dysregulation. Microglia depletion or selective disruption of the NFkB signaling pathway in microglia during HFD prevents the inflammatory response, and reduces food intake and weight gain. Here, we investigated the role of microglial prostaglandin PGE2 receptor 4 (EP4) signaling on the inflammatory response to HFD and metabolic outcomes. Compared to their wildtype counterparts, microglia-specific EP4 knockout (MG EP4-KO) mice on HFD showed reduced weight gain and improved glucose tolerance at 5 weeks. However, the two groups did not differ in glucose tolerance at 12 weeks, despite the MG EP4-KO mice maintaining lower body weight. This decoupling of body weight and glucose impairment indicates a progressive deterioration of glucose homeostasis associated with EP4 deficiency in microglia. Overall, these findings unravel a complex and dynamic interplay between EP4 signaling in microglia, weight gain and glucose imbalance in HFD.

Disclosure
A. Niraula: None. R. Fasnacht: None. K.M. Ness: None. J. Frey: None. M.D. Dorfman: None. J. Thaler: None.

Funding
National Institutes of Health (R01DK119754)
1767-P: Intranasal Naloxone Prevents the Development of Hypoglycemia-Associated Autonomic Failure (HAAF) in Susceptible Individuals
Authors: MANAVALAN ANJALI , MATHIAS PRIYANKA M. , ALEKSIC SANDRA , YIMAGOU ERIC LONTCHI , CAREY MICHELLE , MOY JOY , PATEL TULSI , KUO BRYAN , SANDU OANA , SHAMOON HARRY , HAWKINS MEREDITH 
Published: June 2020

Repeated hypoglycemic episodes can cause HAAF, i.e., blunted counter-regulatory hormone responses. We have shown that activating opiate receptors can induce HAAF in healthy participants subjected to subsequent experimentally induced hypoglycemia. However, we have noted inter-individual variability in the development of HAAF. In our current study we evaluated the effect of blocking opioid receptors with intranasal naloxone in individuals at risk for HAAF.
To identify people susceptible to HAAF, fourteen nondiabetic subjects (13M, age 43.4±8.0, BMI 25.5±2.19 kg/m2) underwent two 120-minute hyperinsulinemic hypoglycemic (nadir 54 mg/dl) clamp studies on Day 1 and a third hypoglycemic clamp study on Day 2. Nine individuals developed HAAF, defined as ≥20% reduction in average epinephrine (EPI) levels (90-120 minutes) between the first and third episodes of hypoglycemia (858 ±161 vs. 494±108 pg/ml, p=0.008).
The HAAF-prone subjects underwent similar 3-episode hypoglycemic studies on two subsequent occasions with hourly placebo (randomized, double-blinded) or naloxone (4 mg) on Day 1. While average EPI levels declined from the first to the third hypoglycemic episode by 42% with placebo (p=0.01), levels did not differ with intranasal naloxone (p=0.67). Similarly, plasma glucagon levels decreased significantly from the first to the third hypoglycemic episode with placebo but were maintained with naloxone (Glucagon 1st vs. 3rd episode: Placebo 31.5±8.07 vs. 21.6±5.3 mg/ml, p=0.03; Naloxone 30.5±7.42 vs. 27.0±6.9 mg/ml, p=0.41). Naloxone did not alter plasma cortisol responses or hypoglycemic symptoms.
This confirms previous reports of inter-individual variability in development of HAAF. Administration of intranasal naloxone during antecedent hypoglycemia prevented HAAF in susceptible individuals. Inhaled naloxone may offer a feasible approach to ameliorate HAAF in targeted individuals at risk for hypoglycemia-related adverse events.

Disclosure
A. Manavalan: None. P.M. Mathias: None. S. Aleksic: None. E. Lontchi Yimagou: None. M. Carey: None. J. Moy: None. T. Patel: None. B. Kuo: None. O. Sandu: None. H. Shamoon: None. M. Hawkins: None.

Funding
National Institutes of Health (R01DK079974)
177-LB: Low 25-Hydroxy Vitamin D Is Associated with Arterial Stiffness in Type 2 Diabetes Mellitus
Authors: MA BINGWEI , CHEN YAO , WANG XINGCHUN , QU SHEN 
Published: June 2020

Background: The aim of this study was to investigate the association between 25-hydroxyvitamin D and arterial stiffness assessed by brachial-ankle pulse wave velocity (baPWV) in type 2 diabetes mellitus(T2DM).
Methods: We identified 1335 diabetes patients from the Department of Endocrinology, Shanghai Tenth People’s Hospital from 1 November 2017 to 2 November 2019. 603 T2DM patients were included in the cross-sectional study. Participants were divided into two group: AS group (baPWV≥1700cm/s) and the control group (baPWV&lt;1700cm/s). Linear correlation was used to evaluate the relationship between 25-hydroxyvitamin D and baPWV. Multiple linear regression and logistic regression analysis were adopted to investigate risk factors for AS.
Results: 1) Patients with AS tended to be older and had a longer duration of diabetes than control group (P&lt;0.001 and P=0.013). Patients with AS were more likely to have diabetic retinopathy and diabetic peripheral neuropathy than the control (56% vs.43%, P=0.002; 66% vs.52%, P=0.001). 2) Compared to patients without AS, patients with AS showed lower 25-hydroxyvitamin D and higher rate of 25-hydroxyvitamin D deficiency than control group (P=0.020 and P=0.011). 3) No matter in all subjects, males or females, baPWV levels were negatively associated with 25-hydroxyvitamin D levels (r=-0.119, P=0.004; r=-0.107, P=0.044; r=-0.128, P=0.043). 4) Multiple linear regression showed that 25-hydroxyvitamin D was the negatively influencing factor of baPWV in whole sample and males (β=-2.207, P=0.014; β=-2.207, P=0.022). Logistic regression showed that age and SBP were risk factor of AS(OR:1.072, 95% CI: 1.048- 1.097, P&lt;0.001; OR:1.028, 95% CI: 1.017-1.038, P&lt;0.001) while VD was protective factor of AS in T2DM patients(OR:0.987, 95% CI: 0.976-0.998, P=0.024).
Conclusion: There was a negatively relationship between 25-hydroxyvitamin D and arterial stiffness assessed by baPWV. High 25-hydroxyvitamin D was found to be a protective factor for arterial stiffness.

Disclosure
B. Ma: None. Y. Chen: None. X. Wang: None. S. Qu: None.

Funding
National Key R&D Program of China (2018YFC1314100, 2016YFC1305600); Shanghai Outstanding Academic Leaders Plan (049)
177-OR: Estimating the Costs of Diabetes Complications in People &lt;65 Years in the U.S. Using Panel Data
Authors: YANG WENYA , CINTINA INNA , HOERGER THOMAS J. , NEUWAHL SIMON , SHAO HUI , LAXY MICHAEL , ZHANG PING 
Published: June 2020

Reliable, accurate, updated cost estimates of treating diabetes complications are needed to assess the financial gain of efforts to prevent and delay diabetes complications and for parameterizing diabetes cost-effectiveness simulation models. Using large longitudinal and geographically diverse claims data from Optum de-identified Normative Health Information dataset between 2007 and 2016, we estimated the annual per-person cost associated with all the main complications in people with diabetes aged &lt;65 years. We identified persons with diabetes using diagnosis codes and distinguished type 1 (T1DM) and type 2 (T2DM) diabetes using both diagnose codes and type of medications. Complications were identified using diagnosis, procedure, or Diagnosis Related Group codes. Longitudinal panel data with a follow-up time of one to ten years were constructed. Costs in both the first and in subsequent years for a complication were estimated using individual fixed-effects models. All costs were adjusted to 2016 dollars. Our final sample included 47,166 persons with T1DM and 608,237 with T2DM. On average, compared to T2DM, the T1DM sample had a longer follow-up time (3.2 vs. 3.0 years) and was younger (39 vs. 52 years). About 46% of T1DM and 30% of T2DM samples had at least one complication. The most common complications were neuropathy, nephropathy, and history of these conditions. The estimated average costs for the three most costly conditions in the first vs. subsequent years were: end stage renal disease ($73,534 vs. $97,431 for T1DM; $94,231 vs. $98,981 for T2DM), congestive heart failure ($41,681 vs. $14,855 for T1DM; $31,202 vs. $7,062 for T2DM), and myocardial infarction ($40,899 vs. $9,496 for T1DM; $45,251 vs. $8,572 for T2DM). For both diabetes types, retinopathy and neuropathy tend to have the lowest costs. Our study provides the most updated and reliable cost estimates for evaluation of the long-term cost-effectiveness of interventions for preventing and managing diabetes.

Disclosure
W. Yang: None. I. Cintina: None. T.J. Hoerger: Research Support; Self; Centers for Disease Control and Prevention, Centers for Medicare and Medicaid Services. S. Neuwahl: None. H. Shao: None. M. Laxy: None. P. Zhang: None.

Funding
Centers for Disease Control and Prevention (200-2016-92270)
1773-P: Postprandial Hyperglycemia after a High–Glycemic Index Meal Activates Brain Areas Associated with Food Cravings and Overeating in T1D
Authors: LENNERZ BELINDA S. , MUNSCH FANNY , ALSOP DAVID C. , STEIL GARRY M. , SIMONSON DONALD C. , LUDWIG DAVID S. 
Published: June 2020

High vs. low glycemic index (GI) foods elicit late postprandial activation of mesolimbic brain areas, which may contribute to the associated increases in hunger, food intake and cravings. It is unknown whether changes in blood glucose or higher insulin levels mediate this activation and its potential adverse downstream effects. Fifteen men with T1D, mean (SD) BMI 21 (1.4) kg/m2, aged 21 (1.6) yr underwent three conditions in random order: C1 - high GI (GI=84) meal with IV insulin to maintain euglycemia; C2 - macronutrient matched low GI (37) meal with IV insulin to maintain euglycemia; C3 - high GI meal with IV insulin to match C2. Insulin was algorithmically adjusted for 4.5 hr with blood glucose checks every 5 min. Brain imaging (arterial spin labeling) was obtained at baseline, in the early (1 hr) and late (4 hr) postprandial period. This design allowed us to compare high vs. low GI meals with similar glucose response (incremental area under the curve 192 [22] vs. 41 [12], p=0.6) but different insulin doses (25 [2] vs. 17 [1] units, p=0.003; C1 vs. C2) or similar insulin doses (17 [1] units each, p=0.5) with different glucose response (1257 [37] vs. 41 [12] mg/dl*h, p&lt;0.001, C3 vs. C2). As expected, a high GI meal elicits increased hunger and late postprandial activation of brain areas linked to food cravings. This activation was mediated by postprandial hyperglycemia rather than insulin level. Thus, a high GI meal may promote overeating with insulin dose deviations in either direction: 1) via mesolimbic signaling if hyperglycemia results from inadequate insulin coverage, or 2) via compensatory carbohydrate intake if excessive coverage causes hypoglycemia.

Disclosure
B.S. Lennerz: None. F. Munsch: None. D.C. Alsop: Other Relationship; Self; General Electric, Hitachi America, Ltd., Philips Healthcare, Siemens Corporation. G.M. Steil: Consultant; Self; Eli Lilly and Company. D.C. Simonson: Stock/Shareholder; Self; GI Windows. Stock/Shareholder; Spouse/Partner; Phase V Technologies, Inc. D.S. Ludwig: None.
1776-P: ROCK1 Deletion in Sim1-Expressing Neurons of the Hypothalamus Leads to Obesity Despite Hypophagia
Authors: LEE HYON , HAN JUNG SUK , UNER AYKUT G. , CHOI SOO J. , PEREIRA RODRIGO M. , SUN XIAOFANG , KIM HYUN JEONG , KIM YOUNG-BUM 
Published: June 2020

The paraventricular nucleus of the hypothalamus (PVN) is a key site in the brain for regulating energy balance. ROCK1 has also been shown to be a major regulator of energy balance and metabolism in the hypothalamus, but its role in the PVN is still unclear. To explore this role, mice selectively lacking ROCK1 in single-minded homolog 1 gene (Sim1) neurons (Sim1-ROCK1-/-), which are densely expressed in the PVN and in parts of the amygdala, were studied. ROCK1 deficiency in Sim1 expressing neurons leads to obesity on regular chow in male and female mice after 11-12 weeks. This effect is due to increased fat mass as assessed by EchoMRI and direct dissection of fat depots. Serum levels of insulin, leptin and free fatty acid in Sim1-ROCK1-/- mice were markedly increased compared to control mice. Surprisingly, daily food intake in Sim1-ROCK1-/- mice were significantly decreased compared with control mice. Moreover, the ability of melanocortin to decrease food intake was impaired when ROCK1 was deleted from Sim1-expressing neurons. No differences in O2 consumption and CO2 production measured by the Comprehensive Lab Animal Monitoring System (CLAMS) were found between obese and lean mice with or without ROCK1 deletion. These data identify ROCK1 as an important mediator of energy balance in the PVN, which leads to a paradoxical obese/hypophagic phenotype. The underlying mechanisms for the divergence in obesity, energy expenditure and caloric intake are being further explored in our lab.

Disclosure
H. Lee: None. J. Han: None. A.G. Uner: None. S.J. Choi: None. R.M. Pereira: None. X. Sun: None. H. Kim: None. Y. Kim: None.