Effects of a Community-Based Lifestyle Intervention on Change in Physical Activity among Economically Disadvantaged Adults with Prediabetes

ERIC Educational Resources Information Center

Hays, Laura M.; Hoen, Helena M.; Slaven, James E.; Finch, Emily A.; Marrero, David G.; Saha, Chandan; Ackermann, Ronald T.

2016-01-01

Background: Moderate weight loss and physical activity (PA) can prevent or delay type 2 diabetes however there is a need for innovative, effective programs to promote PA in high-risk individuals. Purpose: We examined the effect of a group-based adaption of the DPP lifestyle intervention implemented in partnership with the YMCA (YDPP) on changes in…

Cost of a Group Translation of the Diabetes Prevention Program

PubMed Central

Lawlor, Michael S.; Blackwell, Caroline S.; Isom, Scott P.; Katula, Jeffrey A.; Vitolins, Mara Z.; Morgan, Timothy M.; Goff, David C.

2013-01-01

Background Although numerous studies have translated the Diabetes Prevention Program lifestyle intervention into various settings, no study to date has reported a formal cost analysis. Purpose To describe costs associated with the Healthy Living Partnerships to Prevent Diabetes (HELP PD) trial. Design HELP PD was a 24-month RCT testing the impact of a lifestyle weight-loss intervention administered through a diabetes education program and delivered by community health workers (CHWs) on blood glucose and body weight among prediabetics. Setting/participants In all, 301 participants with prediabetes were randomized in Forsyth County NC. Data reported in these analyses were collected in 2007–2011 and analyzed in 2011–2012. Intervention The lifestyle weight-loss group had a 7% weight loss goal achieved and maintained by caloric restriction and increased physical activity. The usual care group received two visits with a registered dietitian and monthly newsletters. Main outcome measures Measures are direct medical costs, direct nonmedical costs and indirect costs over the 2-year study period. Research costs are excluded. Results The direct medical cost (in 2010 dollars) to identify one participant was $16.85. Direct medical costs per capita for participants in the usual care group were $142 and $850 for lifestyle weight-loss participants. Per capita direct costs of care outside the study were $7454 for the usual care group and $5177 for the lifestyle weight-loss group. Per capita direct nonmedical costs were $12,881 for the usual care group and $13,836 for the lifestyle weight-loss group. The lifestyle weight-loss group in HELP PD cost $850 in direct medical costs for 2 years, compared to $2631 in direct medical costs for the first 2 years of DPP. Conclusions A community-based translation of the DPP can be delivered effectively and with reduced costs. PMID:23498303

Circulating natriuretic peptide concentrations reflect changes in insulin sensitivity over time in the Diabetes Prevention Program.

PubMed

Walford, Geoffrey A; Ma, Yong; Christophi, Costas A; Goldberg, Ronald B; Jarolim, Petr; Horton, Edward; Mather, Kieren J; Barrett-Connor, Elizabeth; Davis, Jaclyn; Florez, Jose C; Wang, Thomas J

2014-05-01

We aimed to study the relationship between measures of adiposity, insulin sensitivity and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in the Diabetes Prevention Program (DPP). The DPP is a completed clinical trial. Using stored samples from this resource, we measured BMI, waist circumference (WC), an insulin sensitivity index (ISI; [1/HOMA-IR]) and NT-proBNP at baseline and at 2 years of follow-up in participants randomised to placebo (n = 692), intensive lifestyle intervention (n = 832) or metformin (n = 887). At baseline, log NT-proBNP did not differ between treatment arms and was correlated with baseline log ISI (p < 0.0001) and WC (p = 0.0003) but not with BMI (p = 0.39). After 2 years of treatment, BMI decreased in the lifestyle and metformin groups (both p < 0.0001); WC decreased in all three groups (p < 0.05 for all); and log ISI increased in the lifestyle and metformin groups (both p < 0.001). The change in log NT-proBNP did not differ in the lifestyle or metformin group vs the placebo group (p > 0.05 for both). In regression models, the change in log NT-proBNP was positively associated with the change in log ISI (p < 0.005) in all three study groups after adjusting for changes in BMI and WC, but was not associated with the change in BMI or WC after adjusting for changes in log ISI. Circulating NT-proBNP was associated with a measure of insulin sensitivity before and during preventive interventions for type 2 diabetes in the DPP. This relationship persisted after adjustment for measures of adiposity and was consistent regardless of whether a participant was treated with placebo, intensive lifestyle intervention or metformin.

Medical Care Expenditures for Individuals with Prediabetes: The Potential Cost Savings in Reducing the Risk of Developing Diabetes.

PubMed

Khan, Tamkeen; Tsipas, Stavros; Wozniak, Gregory

2017-10-01

The United States has 86 million adults with prediabetes. Individuals with prediabetes can prevent or delay the development of type 2 diabetes through lifestyle modifications such as participation in the National Diabetes Prevention Program (DPP), thereby mitigating the medical and economic burdens associated with diabetes. A cohort analysis of a commercially insured population was conducted using individual-level claims data from Truven Health MarketScan ® Lab Database to identify adults with prediabetes, track whether they develop diabetes, and compare medical expenditures for those who are newly diagnosed with diabetes to those who are not. This study then illustrates how reducing the risk of developing diabetes by participation in an evidence-based lifestyle change program could yield both positive net savings on medical care expenditures and return on investment (ROI). Annual expenditures are found to be nearly one third higher for those who develop diabetes in subsequent years relative to those who do not transition from prediabetes to diabetes, with an average difference of $2671 per year. At that cost differential, the 3-year ROI for a National DPP is estimated to be as high as 42%. The results show the importance and economic benefits of participation in lifestyle intervention programs to prevent or delay the onset of type 2 diabetes.

Metformin, Lifestyle Intervention, and Cognition in the Diabetes Prevention Program Outcomes Study.

PubMed

Luchsinger, José A; Ma, Yong; Christophi, Costas A; Florez, Hermes; Golden, Sherita H; Hazuda, Helen; Crandall, Jill; Venditti, Elizabeth; Watson, Karol; Jeffries, Susan; Manly, Jennifer J; Pi-Sunyer, F Xavier

2017-07-01

We examined the association of the Diabetes Prevention Program (DPP) intervention arms (lifestyle intervention, metformin, and placebo) with cognition in the Diabetes Prevention Program Outcomes Study (DPPOS). We also examined metformin use, incident type 2 diabetes, and glycemia as exposures. The DPP lasted 2.8 years, followed by a 13-month bridge to DPPOS. Cognition was assessed in DPPOS years 8 and 10 (12 and 14 years after randomization) with the Spanish English Verbal Learning Test (SEVLT), letter fluency and animal fluency tests, Digit Symbol Substitution Test (DSST), and a composite cognitive score. A total of 2,280 participants (749 lifestyle, 776 metformin, and 755 placebo) aged 63.1 ± 10.7 years underwent cognitive assessments; 67.7% women, 54.6% non-Hispanic white, 20.7% non-Hispanic black, 14.6% Hispanic, 5.5% American Indian, and 4.6% Asian; 26.6% were homozygous or heterozygous for APOE-ε4. At the time of cognitive assessment, type 2 diabetes was higher in the placebo group (57.9%; P < 0.001) compared with lifestyle (47.0%) and metformin (50.4%). Metformin exposure was higher in the metformin group (8.72 years; P < 0.001) compared with placebo (1.43 years) and lifestyle (0.96 years). There were no differences in cognition across intervention arms. Type 2 diabetes was not related to cognition, but higher glycated hemoglobin at year 8 was related to worse cognition after confounder adjustment. Cumulative metformin exposure was not related to cognition. Exposure to intensive lifestyle intervention or metformin was not related to cognition among DPPOS participants. Higher glycemia was related to worse cognitive performance. Metformin seemed cognitively safe among DPPOS participants. © 2017 by the American Diabetes Association.

Women Veterans’ Experience With a Web-Based Diabetes Prevention Program: A Qualitative Study to Inform Future Practice

PubMed Central

Ertl, Kristyn; Schneider, Jessica; Vasti, Elena; Makki, Fatima; Richardson, Caroline; Havens, Kathryn; Damschroder, Laura

2015-01-01

Background Diabetes prevention is a national goal and particularly important in the Veterans Health Administration (VHA) where 1 in 4 veterans has diabetes. There is growing evidence to support the use of Web-based diabetes prevention program (DPP) interventions, shown to be as effective and often more feasible than in-person interventions. Objective Our primary objective was to qualitatively explore women veterans’ early experiences with a Web-based DPP intervention. Our secondary objective was to estimate weight loss, participation, and engagement to provide context for our qualitative findings. Methods We conducted and analyzed semistructured interviews and collected data on weight change, participation, and engagement. A total of 17 women veterans with prediabetes from a Midwest VA Women’s Health Clinic were eligible to participate; 15 completed interviews. Results Participants perceived the DPP program as an appealing way of initiating lifestyle changes and made them feel accountable in achieving their daily goals. The online program was convenient because it could be accessed at any time, and many found that it integrated well into daily life. However, some did not like the logging aspect and some found it to be too impersonal. Participants logged in a mean 76 times, posted a mean 46 group messages, and sent a mean 20.5 private messages to the health coach over 16 weeks. Participants lost 5.24% of baseline weight, and 82% (14/17) of participants completed at least 9 of 16 core modules. Conclusions Women veterans’ early experiences with a Web-based DPP intervention were generally positive. Accountability and convenience were key enabling factors for participation and engagement. A Web-based DPP intervention appears to be a promising means of translating the DPP for women veterans with prediabetes. PMID:26006697

Workplace Interventions to Prevent Type 2 Diabetes Mellitus: a Narrative Review

PubMed Central

Fedewa, Allison; Moran, Margaret; O’Brien, Matthew; Ackermann, Ronald; Kullgren, Jeffrey T.

2017-01-01

Purpose of review This study aims to summarize the recent peer-reviewed literature on workplace interventions for prevention of type 2 diabetes mellitus (T2DM), including studies that translate the Diabetes Prevention Program (DPP) curriculum to workplace settings (n = 10) and those that use different intervention approaches to achieve the specific objective of T2DM prevention among employees (n = 3). Recent findings Weight reduction was achieved through workplace interventions to prevent T2DM, though such interventions varied substantially in their effectiveness. The greatest weight loss was reported among intensive lifestyle interventions (i.e., at least 4 months in duration) that implemented the structured DPP curriculum (n = 3). Weight reduction was minimal among less intensive interventions, including those that substantially modified the DPP curriculum (n = 2) and those that used non-DPP intervention approaches to prevent T2DM (n = 3). Most studies (n = 12) reported increased levels of physical activity following the intervention. Summary Implementation of the DPP in workplaces may be an effective strategy to prevent T2DM among employees. PMID:28150162

Model Programs to Address Obesity and Cardiometabolic Disease: Interventions for Suboptimal Nutrition and Sedentary Lifestyles.

PubMed

Nash, Mark S; Kressler, Jochen

2016-09-01

Problems posed by obesity-related endocrine diseases embody a national health crisis. Caloric excess and sedentary lifestyle from which they develop also pose significant challenges for rehabilitation providers. Almost two thirds of the U.S. population are currently overweight or obese, a number that has increased by >10% within the last decade and is expected to grow. An overweight body habitus is strongly associated with clinical hazards, including cardiometabolic syndrome, diabetes hypertension, and coronary artery disease. The component health risks of the cardiometabolic syndrome include coalescing of risk factors that predict a health calamity unless effective interventions can be developed and widely adopted. Obesity by itself is now considered an American Diabetes Association-qualified disability, but it is also disturbingly prevalent in other physical disability groupings of adults and children. This monograph describes successes of the Diabetes Prevention Program (DPP), a National Institutes of Health multisite randomized controlled trial that reported significant weight reduction and a 58% decreased incidence of type-2 diabetes accompanying 1 year of structured lifestyle intervention. This treatment benefit (1) exceeded that of metformin pharmacotherapy, (2) was so powerful that the trial was closed before reaching endpoints, and (3) was judged cost-effective for the patient and society. The DPP roadmap incorporating physical activity, diet, and behavioral approaches has been widely adapted to specific community, faith, racial, ethnic, school, and national populations with excellent outcomes success. The lockstep physical activity approach, activity prescription, and long-term success of the program are described and compared with other programs to illustrate effective countermeasures for the pandemics of obesity and obesity-related cardioendocrine disease. We will illustrate adaptation of the DPP for a cohort of persons with disability from spinal cord injury and the benefits observed. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Effect of regression from prediabetes to normal glucose regulation on long-term reduction in diabetes risk: results from the Diabetes Prevention Program Outcomes Study.

PubMed

Perreault, Leigh; Pan, Qing; Mather, Kieren J; Watson, Karol E; Hamman, Richard F; Kahn, Steven E

2012-06-16

Our objective was to quantify and predict diabetes risk reduction during the Diabetes Prevention Program Outcomes Study (DPPOS) in participants who returned to normal glucose regulation at least once during the Diabetes Prevention Program (DPP) compared with those who consistently met criteria for prediabetes. DPPOS is an ongoing observational study of participants from the DPP randomised trial. For this analysis, diabetes cumulative incidence in DPPOS was calculated for participants with normal glucose regulation or prediabetes status during DPP with and without stratification by previous randomised treatment group. Cox proportional hazards modelling and generalised linear mixed models were used to quantify the effect of previous (DPP) glycaemic status on risk of later (DPPOS) diabetes and normal glucose regulation status, respectively, per SD in change. Included in this analysis were 1990 participants of DPPOS who had been randomly assigned to treatment groups during DPP (736 intensive lifestyle intervention, 647 metformin, 607 placebo). These studies are registered at ClinicalTrials.gov, NCT00004992 (DPP) and NCT00038727 (DPPOS). Diabetes risk during DPPOS was 56% lower for participants who had returned to normal glucose regulation versus those who consistently had prediabetes (hazard ratio [HR] 0·44, 95% CI 0·37-0·55, p<0·0001) and was unaffected by previous group assignment (interaction test for normal glucose regulation and lifestyle intervention, p=0·1722; normal glucose regulation and metformin, p=0·3304). Many, but not all, of the variables that increased diabetes risk were inversely associated with the chance of a participant reaching normal glucose regulation status in DPPOS. Specifically, previous achievement of normal glucose regulation (odds ratio [OR] 3·18, 95% CI 2·71-3·72, p<0·0001), increased β-cell function (OR 1·28; 95% CI 1·18-1·39, p<0·0001), and insulin sensitivity (OR 1·16, 95% CI 1·08-1·25, p<0·0001) were associated with normal glucose regulation in DPPOS, whereas the opposite was true for prediction of diabetes, with increased β-cell function (HR 0·80, 95% CI 0·71-0·89, p<0·0001) and insulin sensitivity (HR 0·83, 95% CI 0·74-0·94, p=0·0001) having a protective effect. Among participants who did not return to normal glucose regulation in DPP, those assigned to the intensive lifestyle intervention had a higher diabetes risk (HR 1·31, 95% CI 1·03-1·68, p=0·0304) and lower chance of normal glucose regulation (OR 0·59, 95% CI 0·42-0·82, p=0·0014) than did the placebo group in DPPOS. We conclude that prediabetes is a high-risk state for diabetes, especially in patients who remain with prediabetes despite intensive lifestyle intervention. Reversion to normal glucose regulation, even if transient, is associated with a significantly reduced risk of future diabetes independent of previous treatment group. US National Institutes of Health. Copyright © 2012 Elsevier Ltd. All rights reserved.

Triglyceride response to an intensive lifestyle intervention is enhanced in carriers of the GCKR Pro446Leu polymorphism.

PubMed

Pollin, Toni I; Jablonski, Kathleen A; McAteer, Jarred B; Saxena, Richa; Kathiresan, Sekar; Kahn, Steven E; Goldberg, Ronald B; Altshuler, David; Florez, Jose C

2011-07-01

Glucokinase regulatory protein (GCKR) regulates the trafficking and enzymatic activity of hepatic glucokinase, the rate-limiting enzyme in glycogen synthesis and glycolysis. The intronic single-nucleotide polymorphism (SNP) rs780094 (intron 16) and the missense SNP rs1260326 (P446L) in the GCKR gene are strongly associated with increased circulating triglyceride and C-reactive protein levels and, paradoxically, reductions in diabetes incidence, fasting glucose levels, and insulin resistance. OBJECTIVE, SETTING, AND PATIENTS: We sought to replicate these associations and evaluate interactions with lifestyle and metformin interventions in the multiethnic Diabetes Prevention Program (DPP). We genotyped the two GCKR SNP in 3346 DPP participants and evaluated association with progression to diabetes and both baseline levels and changes in triglycerides, homeostasis model assessment of insulin resistance (HOMA-IR), oral disposition index, and inflammatory markers along with their interactions with DPP interventions. GCKR variation did not predict development of type 2 diabetes. At baseline, the 446L allele was associated with higher triglyceride and C-reactive protein levels (both P < 0.0001) and lower fasting glucose (P = 0.001) and HOMA-IR (P = 0.06). The lifestyle intervention was associated with a decrease in magnitude of the effect of the 446L allele on triglyceride levels (interaction P = 0.04). Metformin was more effective in reducing HOMA-IR in carriers of the P446 allele (interaction P = 0.05). Intensive lifestyle intervention appears to partially mitigate the effect of the 446L allele on higher triglycerides, whereas the P446 allele appears to enhance responsiveness to the HOMA-IR-lowering effect of metformin.

Testing of diabetes-associated WFS1 polymorphisms in the Diabetes Prevention Program

PubMed Central

Florez, J. C.; Jablonski, K. A.; McAteer, J.; Sandhu, M. S.; Wareham, N. J.; Barroso, I.; Franks, P. W.; Altshuler, D.; Knowler, W. C.

2008-01-01

Aims/hypothesis Wolfram syndrome (diabetes insipidus, diabetes mellitus, optic atrophy and deafness) is caused by mutations in the WFS1 gene. Recently, single nucleotide polymorphisms (SNPs) in WFS1 have been reproducibly associated with type 2 diabetes. We therefore examined the effects of these variants on diabetes incidence and response to interventions in the Diabetes Prevention Program (DPP), in which a lifestyle intervention or metformin treatment was compared with placebo. Methods We genotyped the WFS1 SNPs rs10010131, rs752 854 and rs734312 (H611R) in 3,548 DPP participants and performed Cox regression analysis using genotype, intervention and their interactions as predictors of diabetes incidence. We also evaluated the effect of these SNPs on insulin resistance and beta cell function at 1 year. Results Although none of the three SNPs was associated with diabetes incidence in the overall cohort, white homozygotes for the previously reported protective alleles appeared less likely to develop diabetes in the lifestyle arm. Examination of the publicly available Diabetes Genetics Initiative genome-wide association dataset revealed that rs10012946, which is in strong linkage disequilibrium with the three WFS1 SNPs (r2=0.88–1.0), was associated with type 2 diabetes (allelic odds ratio 0.85, 95% CI 0.75–0.97, p=0.026). In the DPP, we noted a trend towards increased insulin secretion in carriers of the protective variants, although for most SNPs this was seen as compensatory for the diminished insulin sensitivity. Conclusions/interpretation The previously reported protective effect of select WFS1 alleles may be magnified by a lifestyle intervention. These variants appear to confer an improvement in beta cell function. PMID:18060660

Evaluating the Cost-Effectiveness of Lifestyle Modification versus Metformin Therapy for the Prevention of Diabetes in Singapore

PubMed Central

Png, May Ee; Yoong, Joanne Su-Yin

2014-01-01

Background In Singapore, as diabetes is an increasingly important public health issue, the cost-effectiveness of pursuing lifestyle modification programs and/or alternative prevention strategies is of critical importance for policymakers. While the US Diabetes Prevention Program (DPP) compared weight loss through lifestyle modification with oral treatment of diabetes drug metformin to prevent/delay the onset of type 2 diabetes in pre-diabetic subjects, no data on either the actual or potential cost effectiveness of such a program is available for East or South-east Asian populations. This study estimates the 3-year cost-effectiveness of lifestyle modification and metformin among pre-diabetic subjects from a Singapore health system and societal perspective. Methodology Cost effectiveness was analysed from 2010–2012 using a decision-based model to estimate the rates of getting diabetes, healthcare costs and health-related quality of life. Cost per quality-adjusted life year (QALY) was estimated using costs relevant to the time horizon of the study from Singapore. All costs are expressed in 2012 US dollars. Principal Findings The total economic cost for non-diabetic subjects from the societal perspective was US$25,867, US$28,108 and US$26,177 for placebo, lifestyle modification and metformin intervention respectively. For diabetic patients, the total economic cost from the societal perspective was US$32,921, US$35,163 and US$33,232 for placebo, lifestyle modification and metformin intervention respectively. Lifestyle modification relative to placebo is likely to be associated with an incremental cost per QALY gained at US$36,663 while that of metformin intervention is likely to be US$6,367 from a societal perspective. Conclusion Based on adaptation of the DPP data to local conditions, both lifestyle modification and metformin intervention are likely to be cost-effective and worth implementing in Singapore to prevent or delay the onset of type 2 diabetes. However, the cost of lifestyle modification from the societal perspective would have to be reduced in order to match the cost-effectiveness of metformin intervention. PMID:25203633

Financial incentives for diabetes prevention in a Medicaid population: Study design and baseline characteristics.

PubMed

Desai, Jay; Taylor, Gretchen; Vazquez-Benitez, Gabriela; Vine, Sara; Anderson, Julie; Garrett, Joyce E; Gilmer, Todd; Vue-Her, Houa; Schiff, Jeff; Rinn, Sarah; Engel, Katelyn; Michael, Amy; O'Connor, Patrick J

2017-02-01

Medicaid beneficiaries at high risk for diabetes can benefit from the Diabetes Prevention Program (DPP) lifestyle intervention. The We Can Prevent Diabetes (WCPD) trial examined whether financial incentives are more effective than no financial incentives in sustaining participation in the DPP and increasing weight loss. Here we describe the study design and baseline characteristics. The WCPD was a 3-arm group-randomized controlled trial. Medicaid beneficiaries were aged 18 to 74years, had prediabetes or gestational diabetes, and were overweight or obese. Subjects enrolled from 13 primary care clinics into groups of 8 to 15 participants. Participants received the 12-month DPP delivered by the YMCA or trained clinic staff, free of costs. Participants from groups randomized into the intervention conditions were eligible to receive incentives up to $520 by attending sessions and meeting weight loss goals. The WCPD enrolled 1154 participants into 98 groups. Among the 847 attending at least one DPP session, 71.2% were women; the mean age was 48.3years; 79.3% were obese; and 87.6% entered the study with an elevated HbA1c or fasting plasma glucose. Participants' primary languages were Somali (21.0%), Hmong (3.1%), Spanish (2.2%), or English (72.4%). The WCPD trial demonstrated that a collaborative approach with primary care clinics and the YMCA can efficiently identify, enroll, and deliver the 12-month DPP to Medicaid beneficiaries. If the WCPD incentive arms increase attendance and weight loss, the use of financial incentives may be an avenue for engaging low-income, high-risk patients in lifestyle change. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

A Formative Evaluation of a Diabetes Prevention Program Using the RE-AIM Framework in a Learning Health Care System, Utah, 2013-2015.

PubMed

Brunisholz, Kimberly D; Kim, Jaewhan; Savitz, Lucy A; Hashibe, Mia; Gren, Lisa H; Hamilton, Sharon; Huynh, Kelly; Joy, Elizabeth A

2017-07-20

Evaluation of interventions can help to close the gap between research and practice but seldom takes place during implementation. Using the RE-AIM framework, we conducted a formative evaluation of the first year of the Intermountain Healthcare Diabetes Prevention Program (DPP). Adult patients who met the criteria for prediabetes (HbA1c of 5.70%-6.49% or fasting plasma glucose of 100-125 mg/dL) were attributed to a primary care provider from August 1, 2013, through July 31, 2014. Physicians invited eligible patients to participate in the program during an office visit. We evaluated 1) reach, with data on patient eligibility, participation, and representativeness; 2) effectiveness, with data on attaining a 5% weight loss; 3) adoption, with data on providers and clinics that referred patients to the program; and 4) implementation, with data on patient encounters. We did not measure maintenance. Of the 6,862 prediabetes patients who had an in-person office visit with their provider, 8.4% of eligible patients enrolled. Likelihood of participation was higher among patients who were female, aged 70 years or older, or overweight; had depression and higher weight at study enrollment; or were prescribed metformin. DPP participants were more likely than nonparticipants to achieve a 5% weight loss (odds ratio, 1.70; 95% confidence interval, 1.29-2.25; P < .001). Providers from 7 of 8 regions referred patients to the DPP; 174 providers at 53 clinics enrolled patients. The mean number of DPP counseling encounters per patient was 2.3 (range, 1-16). The RE-AIM framework was useful for estimating the formative impact (ie, reach, effectiveness, adoption, and implementation fidelity) of a DPP-based lifestyle intervention deployed in a learning health care system.

Translating the Diabetes Prevention Program for Northern Plains Indian Youth Through Community-Based Participatory Research Methods

PubMed Central

Brown, Blakely D.; Harris, Kari Jo; Harris, Jeri Lyn; Parker, Martin; Ricci, Christiana; Noonan, Curtis

2012-01-01

Purpose The purpose of this study was to use a community-based participatory research (CBPR) approach to translate the original Diabetes Prevention Program (DPP) to be age and culturally specific for American Indian (AI) youth. Methods Tribally enrolled members on 2 Montana Indian reservations conducted focus groups and interviews to discuss community members’ perspectives of factors that encouraged or were barriers to healthy diet and exercise behaviors in AI youth. In total, 31 community members, aged 10 to 68 years old, participated in 4 focus groups and 14 individual interviews. Participants were self-identified as elder, cultural expert, tribal health worker, educator, parent/guardian, youth, or school food service worker. Researchers analyzed transcripts based on inductive methods of grounded theory. Results Data analysis revealed translating the DPP to youth was contingent on the lessons incorporating cultural strategies for healthy behaviors in youth such as berry picking, gardening, horseback riding, and dancing; improving knowledge and access to healthy foods and physical activity for youth and their parents; having interactive, hands-on learning activities for healthy lifestyles in the DPP lessons; using a group format and tribal members to deliver the DPP lessons; and having tribal elders talk to youth about the importance of adopting healthy behaviors when they are young. Conclusions A CBPR approach engaged community members to identify strategies inherent in their culture, tradition, and environment that could effectively translate the DPP to Montana Indian youth living in rural reservation communities. PMID:20944056

Design of a Cluster-Randomized Controlled Trial of a Diabetes Prevention Program within African-American Churches: The Fit Body and Soul Study

PubMed Central

Williams, Lovoria B.; Sattin, Richard W.; Dias, James; Garvin, Jane T.; Marion, Lucy; Joshua, Thomas; Kriska, Andrea; Kramer, M. Kaye; Echouffo-Tcheugui, Justin B.; Freeman, Arin; Narayan, K.M. Venkat

2013-01-01

Evidence from varied community settings has shown that the Group Lifestyle Balance (GLB) Program and other adaptations of the Diabetes Prevention Program (DPP) intervention are effective in lowering diabetes risk. Most DPP data originated from studies of pre-diabetic whites, with only sparse evidence of the effect of DPP in African Americans (AAs) in community settings. This paper describes the design, methods, baseline characteristics and cost effective measures, of a single-blinded, cluster- randomized trial of a faith-based adaptation of the GLB program, Fit Body and Soul (FBAS). The major aims are to test efficacy and cost utility of FBAS in twenty AA churches. Randomization occurred at the church level and 604 AA overweight/obese (BMI≥25 kg/m2) adults with fasting plasma glucose range from normal to pre-diabetic received either FBAS or a health-education comparison program. FBAS is a group-based, multi-level intervention delivered by trained church health advisors (health professionals from within the church), with the goal of ≥7% weight loss, achieved through increasing physical activity, healthy eating and behavior modification. The primary outcome is weight change at 12-weeks post intervention. Secondary outcomes include hemoglobin A1C, fasting plasma glucose, waist circumference, blood pressure, physical activity level, quality of life measures, and cost-effectiveness. FBAS is the largest known cohort of AAs enrolled in a faith-based DPP translation. Reliance on health professionals from within the church for program implementation and the cost analysis are unique aspects of this trial. The design provides a model for faith-based DPPs and holds promise for program sustainability and widespread dissemination. PMID:23354313

Evaluation of a type 2 diabetes prevention program using a commercial weight management provider for non-diabetic hyperglycemic patients referred by primary care in the UK

PubMed Central

Piper, Carolyn; Marossy, Agnes; Griffiths, Zoe; Adegboye, Amanda

2017-01-01

Objectives To determine if a diabetes prevention program (DPP) delivered by a commercial weight management provider using a UK primary care referral pathway could reduce the progression to type 2 diabetes (T2D) in those diagnosed with non-diabetic hyperglycemia (NDH—being at high risk of developing T2D). Research design This is a quasi-experimental translational research study. Methods 14 primary care practices identified, recruited and referred patients with NDH (fasting plasma glucose ≥5.5 to ≤6.9 mmol/L and/or glycated hemoglobin (HbA1c) ≥42 to 47 mmol/mol (6.0%–6.4%)) and a body mass index (BMI) ≥30 kg/m2 to a DPP. Eligible patients were asked to contact Weight Watchers to book onto their DPP, an intensive lifestyle intervention which included a 90 min activation session followed by the offer of 48 weekly Weight Watchers community group meetings. Patients’ blood tests were repeated by primary care, weight change plus self-reported data was recorded by Weight Watchers. Results 166 patients were referred to the program and 149 were eligible. 79% of eligible patients attended an activation session (117 eligible patients) and 77% started the weekly sessions. The study sample was primarily female (75%), white (90%), with 5% living in the most deprived quintile in the UK. Using intention-to-treat analysis, the DPP resulted in a mean reduction in HbA1c of 2.84 mmol/mol at 12 months (from 43.42±1.28 to 40.58±3.41, p<0.01). 38% of patients returned to normoglycemia and 3% developed T2D at 12 months. There was a mean weight reduction in BMI of 3.2 kg/m2 at 12 months (35.5 kg/m2±5.4 to 32.3 kg/m2±5.2, p<0.01). Conclusion A UK primary care referral route partnered with this commercial weight management provider can deliver an effective DPP. The lifestyle changes and weight loss achieved in the intervention translated into considerable reductions in diabetes risk, with an immediate and significant public health impact. PMID:29225891

Evaluation of a type 2 diabetes prevention program using a commercial weight management provider for non-diabetic hyperglycemic patients referred by primary care in the UK.

PubMed

Piper, Carolyn; Marossy, Agnes; Griffiths, Zoe; Adegboye, Amanda

2017-01-01

To determine if a diabetes prevention program (DPP) delivered by a commercial weight management provider using a UK primary care referral pathway could reduce the progression to type 2 diabetes (T2D) in those diagnosed with non-diabetic hyperglycemia (NDH-being at high risk of developing T2D). This is a quasi-experimental translational research study. 14 primary care practices identified, recruited and referred patients with NDH (fasting plasma glucose ≥5.5 to ≤6.9 mmol/L and/or glycated hemoglobin (HbA1c) ≥42 to 47 mmol/mol (6.0%-6.4%)) and a body mass index (BMI) ≥30 kg/m 2 to a DPP. Eligible patients were asked to contact Weight Watchers to book onto their DPP, an intensive lifestyle intervention which included a 90 min activation session followed by the offer of 48 weekly Weight Watchers community group meetings. Patients' blood tests were repeated by primary care, weight change plus self-reported data was recorded by Weight Watchers. 166 patients were referred to the program and 149 were eligible. 79% of eligible patients attended an activation session (117 eligible patients) and 77% started the weekly sessions. The study sample was primarily female (75%), white (90%), with 5% living in the most deprived quintile in the UK. Using intention-to-treat analysis, the DPP resulted in a mean reduction in HbA1c of 2.84 mmol/mol at 12 months (from 43.42±1.28 to 40.58±3.41, p<0.01). 38% of patients returned to normoglycemia and 3% developed T2D at 12 months. There was a mean weight reduction in BMI of 3.2 kg/m 2 at 12 months (35.5 kg/m 2 ±5.4 to 32.3 kg/m 2 ±5.2, p<0.01). A UK primary care referral route partnered with this commercial weight management provider can deliver an effective DPP. The lifestyle changes and weight loss achieved in the intervention translated into considerable reductions in diabetes risk, with an immediate and significant public health impact.

Recruitment for a Diabetes Prevention Program translation effort in a worksite setting.

PubMed

Taradash, J; Kramer, M; Molenaar, D; Arena, V; Vanderwood, K; Kriska, Andrea M

2015-03-01

The success of the Diabetes Prevention Program (DPP) lifestyle intervention has led to community-based translation efforts in a variety of settings. One community setting which holds promise for the delivery of prevention intervention is the worksite; however, information regarding recruitment in this setting is limited. The current effort describes the initial processes surrounding provision of an adapted DPP lifestyle intervention at a corporate worksite. Investigators and key management at the worksite collaborated to develop and implement a recruitment plan for the intervention focusing on 1) in-person onsite activities and 2) implementation of a variety of media recruitment tools and methods. Adult, non-diabetic overweight/obese employees and family members with pre-diabetes and/or the metabolic syndrome were eligible for the study. Telephone pre-screening was completed for 176 individuals resulting in 171 eligible for onsite screening. Of that number, 160 completed onsite screening, 107 met eligibility criteria, and 89 enrolled in the study. Support from worksite leadership, an invested worksite planning team and a solid recruitment plan consisting of multiple strategies were identified as crucial elements of this effective workplace recruitment effort. A worksite team successfully developed and implemented a recruitment plan using existing mechanisms appropriate to that worksite in order to identify and enroll eligible individuals. The results of this effort indicate that employee recruitment in a worksite setting is feasible as the first step in offering onsite behavioral lifestyle intervention programs as part of a widespread dissemination plan to prevent diabetes and lower risk for cardiovascular disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Increasing the effectiveness of the Diabetes Prevention Program through if-then plans: study protocol for the randomized controlled trial of the McGill CHIP Healthy Weight Program.

PubMed

Knäuper, Bärbel; Ivanova, Elena; Xu, Zhen; Chamandy, Melodie; Lowensteyn, Ilka; Joseph, Lawrence; Luszczynska, Aleksandra; Grover, Steven

2014-05-18

The Diabetes Prevention Program (DPP) is highly effective in promoting weight loss in overweight and obese individuals. However, one-on-one DPP sessions are costly. As a cost-saving alternative, a group version of the DPP, called Group Lifestyle Balance program (GLB), has been developed but has been shown to be less effective. The aim of this two-arm parallel randomized controlled trial is to increase the effectiveness of the GLB by integrating habit formation techniques, namely if-then plans and their mental practice, into the program. A total of 154 participants will be randomized to a standard or enriched GLB program. For the enriched GLB program, if-then plans and their mental practice will be integrated into the standard GLB program. Participants will be overweight or obese men and women (BMI of 28 to 45 kg/m2, waist circumference ≥ 88 for women, ≥ 102 for men, 18 to 75 years of age) who do less than 200 minutes of self-reported moderate or vigorous exercise per week. Measures will be completed at baseline, 3 months, post-intervention (12 months), and 12 months post-intervention (24 months). The primary outcome measure is weight loss at 3, 12, and 24 months. Secondary outcomes include percent reaching weight loss goal, physical activity at 3, 12, and 24 months, and weight-related risk factors (waist circumference, hemoglobin A1c, systolic/diastolic blood pressure, total cholesterol/HDL ratio). Standardized training of the life-style coaches, use of standardized manuals, and audio taping and reviewing of the sessions will ensure intervention fidelity. The study will provide evidence-based data on the effectiveness of an enhanced GLB intervention in promoting weight loss and in reducing weight-related risk factors for chronic health problems. Ethical clearance has been received from the Research Ethics and Compliance Board of the Faculty of Medicine Research and Graduate Studies Office at McGill University (Montreal, Canada). ClinicalTrials.gov Identifier: NCT02008435. Registered 6 December 2013.

Genetic risk of progression to type 2 diabetes and response to intensive lifestyle or metformin in prediabetic women with and without a history of gestational diabetes mellitus.

PubMed

Sullivan, Shannon D; Jablonski, Kathleen A; Florez, Jose C; Dabelea, Dana; Franks, Paul W; Dagogo-Jack, Sam; Kim, Catherine; Knowler, William C; Christophi, Costas A; Ratner, Robert

2014-04-01

OBJECTIVE The Diabetes Prevention Program (DPP) trial investigated rates of progression to diabetes among adults with prediabetes randomized to treatment with placebo, metformin, or intensive lifestyle intervention. Among women in the DPP, diabetes risk reduction with metformin was greater in women with prior gestational diabetes mellitus (GDM) compared with women without GDM but with one or more previous live births. RESEARCH DESIGN AND METHODS We asked if genetic variability could account for these differences by comparing β-cell function and genetic risk scores (GRS), calculated from 34 diabetes-associated loci, between women with and without histories of GDM. RESULTS β-Cell function was reduced in women with GDM. The GRS was positively associated with a history of GDM; however, the GRS did not predict progression to diabetes or modulate response to intervention. CONCLUSIONS These data suggest that a diabetes-associated GRS is associated with development of GDM and may characterize women at risk for development of diabetes due to β-cell dysfunction.

Extension of type 2 diabetes genome-wide association scan results in the diabetes prevention program.

PubMed

Moore, Allan F; Jablonski, Kathleen A; McAteer, Jarred B; Saxena, Richa; Pollin, Toni I; Franks, Paul W; Hanson, Robert L; Shuldiner, Alan R; Knowler, William C; Altshuler, David; Florez, Jose C

2008-09-01

Genome-wide association scans (GWASs) have identified novel diabetes-associated genes. We evaluated how these variants impact diabetes incidence, quantitative glycemic traits, and response to preventive interventions in 3,548 subjects at high risk of type 2 diabetes enrolled in the Diabetes Prevention Program (DPP), which examined the effects of lifestyle intervention, metformin, and troglitazone versus placebo. We genotyped selected single nucleotide polymorphisms (SNPs) in or near diabetes-associated loci, including EXT2, CDKAL1, CDKN2A/B, IGF2BP2, HHEX, LOC387761, and SLC30A8 in DPP participants and performed Cox regression analyses using genotype, intervention, and their interactions as predictors of diabetes incidence. We evaluated their effect on insulin resistance and secretion at 1 year. None of the selected SNPs were associated with increased diabetes incidence in this population. After adjustments for ethnicity, baseline insulin secretion was lower in subjects with the risk genotype at HHEX rs1111875 (P = 0.01); there were no significant differences in baseline insulin sensitivity. Both at baseline and at 1 year, subjects with the risk genotype at LOC387761 had paradoxically increased insulin secretion; adjustment for self-reported ethnicity abolished these differences. In ethnicity-adjusted analyses, we noted a nominal differential improvement in beta-cell function for carriers of the protective genotype at CDKN2A/B after 1 year of troglitazone treatment (P = 0.01) and possibly lifestyle modification (P = 0.05). We were unable to replicate the GWAS findings regarding diabetes risk in the DPP. We did observe genotype associations with differences in baseline insulin secretion at the HHEX locus and a possible pharmacogenetic interaction at CDKNA2/B.

Mothers After Gestational Diabetes in Australia Diabetes Prevention Program (MAGDA-DPP) post-natal intervention: study protocol for a randomized controlled trial

PubMed Central

2013-01-01

Background Gestational diabetes mellitus (GDM) is defined as glucose intolerance with its onset or first recognition during pregnancy. Post-GDM women have a life-time risk exceeding 70% of developing type 2 diabetes mellitus (T2DM). Lifestyle modifications reduce the incidence of T2DM by up to 58% for high-risk individuals. Methods/Design The Mothers After Gestational Diabetes in Australia Diabetes Prevention Program (MAGDA-DPP) is a randomized controlled trial aiming to assess the effectiveness of a structured diabetes prevention intervention for post-GDM women. This trial has an intervention group participating in a diabetes prevention program (DPP), and a control group receiving usual care from their general practitioners during the same time period. The 12-month intervention comprises an individual session followed by five group sessions at two-week intervals, and two follow-up telephone calls. A total of 574 women will be recruited, with 287 in each arm. The women will undergo blood tests, anthropometric measurements, and self-reported health status, diet, physical activity, quality of life, depression, risk perception and healthcare service usage, at baseline and 12 months. At completion, primary outcome (changes in diabetes risk) and secondary outcome (changes in psychosocial and quality of life measurements and in cardiovascular disease risk factors) will be assessed in both groups. Discussion This study aims to show whether MAGDA-DPP leads to a reduction in diabetes risk for post-GDM women. The characteristics that predict intervention completion and improvement in clinical and behavioral measures will be useful for further development of DPPs for this population. Trial registration Australian New Zealand Clinical Trials Registry ANZCTRN 12610000338066 PMID:24135085

Mothers After Gestational Diabetes in Australia Diabetes Prevention Program (MAGDA-DPP) post-natal intervention: study protocol for a randomized controlled trial.

PubMed

Shih, Sophy T F; Davis-Lameloise, Nathalie; Janus, Edward D; Wildey, Carol; Versace, Vincent L; Hagger, Virginia; Asproloupos, Dino; O'Reilly, Sharleen; Phillips, Paddy A; Ackland, Michael; Skinner, Timothy; Oats, Jeremy; Carter, Rob; Best, James D; Dunbar, James A

2013-10-17

Gestational diabetes mellitus (GDM) is defined as glucose intolerance with its onset or first recognition during pregnancy. Post-GDM women have a life-time risk exceeding 70% of developing type 2 diabetes mellitus (T2DM). Lifestyle modifications reduce the incidence of T2DM by up to 58% for high-risk individuals. The Mothers After Gestational Diabetes in Australia Diabetes Prevention Program (MAGDA-DPP) is a randomized controlled trial aiming to assess the effectiveness of a structured diabetes prevention intervention for post-GDM women. This trial has an intervention group participating in a diabetes prevention program (DPP), and a control group receiving usual care from their general practitioners during the same time period. The 12-month intervention comprises an individual session followed by five group sessions at two-week intervals, and two follow-up telephone calls. A total of 574 women will be recruited, with 287 in each arm. The women will undergo blood tests, anthropometric measurements, and self-reported health status, diet, physical activity, quality of life, depression, risk perception and healthcare service usage, at baseline and 12 months. At completion, primary outcome (changes in diabetes risk) and secondary outcome (changes in psychosocial and quality of life measurements and in cardiovascular disease risk factors) will be assessed in both groups. This study aims to show whether MAGDA-DPP leads to a reduction in diabetes risk for post-GDM women. The characteristics that predict intervention completion and improvement in clinical and behavioral measures will be useful for further development of DPPs for this population. Australian New Zealand Clinical Trials Registry ANZCTRN 12610000338066.

Metabolic Syndrome Components and Their Response to Lifestyle and Metformin Interventions are Associated with Differences in Diabetes Risk in Persons with Impaired Glucose Tolerance

PubMed Central

Florez, Hermes; Temprosa, Marinella G; Orchard, Trevor J; Mather, Kieren J; Marcovina, Santica M; Barrett-Connor, Elizabeth; Horton, Edward; Saudek, Christopher; Pi-Sunyer, Xavier F; Ratner, Robert E; Goldberg, Ronald B

2013-01-01

Aims To determine the association of metabolic syndrome (MetS) and its components with diabetes risk in participants with impaired glucose tolerance (IGT), and whether intervention-related changes in MetS lead to differences in diabetes incidence. Methods We used the NCEP/ATP III revised MetS definition at baseline and intervention-related changes of its components to predict incident diabetes using Cox models in 3234 Diabetes Prevention Program (DPP) participants with IGT over an average follow-up of 3.2 years. Results In an intention-to-treat analysis, the demographic-adjusted hazard ratios (95%CI) for diabetes in those with MetS (versus no MetS) at baseline were 1.7(1.3-2.3), 1.7(1.2-2.3), and 2.0(1.3-3.0) for placebo, metformin, and lifestyle groups, respectively. Higher levels of fasting plasma glucose and triglycerides at baseline were independently associated with increased risk of diabetes. Greater waist circumference (WC) was associated with higher risk in placebo and lifestyle groups, but not in the metformin group. In a multivariate model, favorable changes in WC (placebo and lifestyle) and HDLc (placebo and metformin) contributed to reduced diabetes risk. Conclusions MetS and some of its components are associated with increased diabetes incidence in persons with IGT in a manner that differed according to DPP intervention. After hyperglycemia, the most predictive factors for diabetes were baseline hypertriglyceridemia and both baseline and lifestyle-associated changes in waist circumference. Targeting these cardio-metabolic risk factors may help to assess the benefits of interventions that reduce diabetes incidence. PMID:24118860

The PILI@Work Program: a translation of the diabetes prevention program to Native Hawaiian-serving worksites in Hawai'i.

PubMed

Townsend, Claire K M; Miyamoto, Robin E S; Antonio, Mapuana; Zhang, Guangxing; Paloma, Diane; Basques, DeAnna; Braun, Kathryn L; Kaholokula, Joseph Keawe'aimoku

2016-06-01

A previously translated Diabetes Prevention Program Lifestyle Intervention (DPP-LI) was adapted for delivery as a worksite-based intervention, called PILI@Work, to address obesity disparities in Native Hawaiians/Pacific Islanders. This study examined the effectiveness of PILI@Work and factors associated with weight loss at post-intervention. Overweight/obese employees of 15 Native Hawaiian-serving organizations received the 3-month component of PILI@Work. Assessments included weight, systolic/diastolic blood pressure, physical activity and functioning, fat intake, locus of weight control, social support, and self-efficacy. Weight, systolic/diastolic blood pressure, physical functioning, physical activity frequency, fat intake, family support, and eating self-efficacy improved from pre- to post-intervention. Regression analysis indicated that worksite type, decreased diastolic blood pressure, increased physical activity, and more internalized locus of weight control were significantly associated with 3-month weight loss. PILI@Work initiated weight loss in Native Hawaiians/Pacific Islanders. DPP-LI translated to worksite settings and tailored for specific populations can be effective for addressing obesity.

Does a History of Gestational Diabetes Mellitus Affect Key Outcomes in Women Participating in a Diabetes Prevention Program?

PubMed

Brokaw, Sarah M; Carpenedo, Dorota; Campbell, Paul; Butcher, Marcene K; Helgerson, Steven D; Harwell, Todd S

2018-04-01

Objectives To evaluate lifestyle change outcomes among women with and without a history of gestational diabetes mellitus (GDM) enrolled in the Montana Diabetes Prevention Program (DPP). Methods Participation, self-monitoring behavior, weight loss, and cardiometabolic risk reduction were compared among 5091 women at high-risk for type 2 diabetes, with and without a history of GDM, enrolled in the Montana DPP between 2008 and 2015. Results Women with a history of GDM (6% of enrolled women, n = 283) were significantly younger than women without GDM. No significant differences in participation, self-monitoring fat intake, achievement of the physical activity goal, or weight loss were found among women with and without a history of GDM. Overall, women lost an average of 5.0 kg (± 6.5), and 45 and 29% of women achieved 5 and 7% weight loss, respectively. Both groups lost significant and comparable amounts of weight. After adjusting for age and other factors, no differences were found in achievement of ≥ 5% weight loss (AOR 0.84; 95% CI 0.61-1.16) or the ≥ 7% weight loss goal (AOR 1.04; 95% CI 0.73-1.47) among women with and without a history of GDM. Conclusions for Practice Our findings suggest that women with and without a history of GDM successfully participate in and achieve significant weight loss in the DPP. Health care providers should identify and refer women with risk factors for type 2 diabetes, including a history of GDM, to a DPP within their community.

Cardiometabolic Risk Factor Changes Observed in Diabetes Prevention Programs in US Settings: A Systematic Review and Meta-analysis

PubMed Central

Zabetian, Azadeh; Goodman, Michael; Echouffo-Tcheugui, Justin B.; Albright, Ann L.; Gregg, Edward W.; Ali, Mohammed K.

2016-01-01

Background The Diabetes Prevention Program (DPP) study showed that weight loss in high-risk adults lowered diabetes incidence and cardiovascular disease risk. No prior analyses have aggregated weight and cardiometabolic risk factor changes observed in studies implementing DPP interventions in nonresearch settings in the United States. Methods and Findings In this systematic review and meta-analysis, we pooled data from studies in the United States implementing DPP lifestyle modification programs (focused on modest [5%–7%] weight loss through ≥150 min of moderate physical activity per week and restriction of fat intake) in clinical, community, and online settings. We reported aggregated pre- and post-intervention weight and cardiometabolic risk factor changes (fasting blood glucose [FBG], glycosylated hemoglobin [HbA1c], systolic or diastolic blood pressure [SBP/DBP], total [TC] or HDL-cholesterol). We searched the MEDLINE, EMBASE, Cochrane Library, and Clinicaltrials.gov databases from January 1, 2003, to May 1, 2016. Two reviewers independently evaluated article eligibility and extracted data on study designs, populations enrolled, intervention program characteristics (duration, number of core and maintenance sessions), and outcomes. We used a random effects model to calculate summary estimates for each outcome and associated 95% confidence intervals (CI). To examine sources of heterogeneity, results were stratified according to the presence of maintenance sessions, risk level of participants (prediabetes or other), and intervention delivery personnel (lay or professional). Forty-four studies that enrolled 8,995 participants met eligibility criteria. Participants had an average age of 50.8 years and body mass index (BMI) of 34.8 kg/m2, and 25.2% were male. On average, study follow-up was 9.3 mo (median 12.0) with a range of 1.5 to 36 months; programs offered a mean of 12.6 sessions, with mean participant attendance of 11.0 core sessions. Sixty percent of programs offered some form of post-core maintenance (either email or in person). Mean absolute changes observed were: weight -3.77 kg (95% CI: -4.55; -2.99), HbA1c -0.21% (-0.29; -0.13), FBG -2.40 mg/dL (-3.59; -1.21), SBP -4.29 mmHg (-5.73, -2.84), DBP -2.56 mmHg (-3.40, 1.71), HDL +0.85 mg/dL (-0.10, 1.60), and TC -5.34 mg/dL (-9.72, -0.97). Programs with a maintenance component achieved greater reductions in weight (additional -1.66kg) and FBG (additional -3.14 mg/dl). Findings are subject to incomplete reporting and heterogeneity of studies included, and confounding because most included studies used pre-post study designs. Conclusions DPP lifestyle modification programs achieved clinically meaningful weight and cardiometabolic health improvements. Together, these data suggest that additional value is gained from these programs, reinforcing that they are likely very cost-effective. PMID:27459705

Recruitment into diabetes prevention programs: what is the impact of errors in self-reported measures of obesity?

PubMed

Hernan, Andrea; Philpot, Benjamin; Janus, Edward D; Dunbar, James A

2012-07-08

Error in self-reported measures of obesity has been frequently described, but the effect of self-reported error on recruitment into diabetes prevention programs is not well established. The aim of this study was to examine the effect of using self-reported obesity data from the Finnish diabetes risk score (FINDRISC) on recruitment into the Greater Green Triangle Diabetes Prevention Project (GGT DPP). The GGT DPP was a structured group-based lifestyle modification program delivered in primary health care settings in South-Eastern Australia. Between 2004-05, 850 FINDRISC forms were collected during recruitment for the GGT DPP. Eligible individuals, at moderate to high risk of developing diabetes, were invited to undertake baseline tests, including anthropometric measurements performed by specially trained nurses. In addition to errors in calculating total risk scores, accuracy of self-reported data (height, weight, waist circumference (WC) and Body Mass Index (BMI)) from FINDRISCs was compared with baseline data, with impact on participation eligibility presented. Overall, calculation errors impacted on eligibility in 18 cases (2.1%). Of n = 279 GGT DPP participants with measured data, errors (total score calculation, BMI or WC) in self-report were found in n = 90 (32.3%). These errors were equally likely to result in under- or over-reported risk. Under-reporting was more common in those reporting lower risk scores (Spearman-rho = -0.226, p-value < 0.001). However, underestimation resulted in only 6% of individuals at high risk of diabetes being incorrectly categorised as moderate or low risk of diabetes. Overall FINDRISC was found to be an effective tool to screen and recruit participants at moderate to high risk of diabetes, accurately categorising levels of overweight and obesity using self-report data. The results could be generalisable to other diabetes prevention programs using screening tools which include self-reported levels of obesity.

Diabetes Prevention Program Community Outreach Perspectives on Lifestyle Training and Translation

PubMed Central

Venditti, Elizabeth M.; Kramer, M. Kaye

2013-01-01

The gap between what is known from clinical efficacy research and the systematic community translation of diabetes prevention programs is narrowing. During the past 5 years, numerous randomized and nonrandomized dissemination studies have evaluated the modified delivery of structured Diabetes Prevention Program (DPP) interventions in diverse real-world settings. Programs of sufficient dose and duration, implemented with fidelity, have reported weight losses in the range of 4%–7% with associated improvements in cardiometabolic risk factors at 6 and 12 months from baseline. The current article describes some of the experiences and perspectives of a team of University of Pittsburgh researchers as they have engaged in these efforts. PMID:23498296

Healthy Living Partnerships to Prevent Diabetes (HELP PD): Design and Methods

PubMed Central

Katula, Jeffrey A.; Vitolins, Mara Z.; Rosenberger, Erica L.; Blackwell, Caroline; Espeland, Mark A.; Lawlor, Michael S.; Rejeski, W. Jack; Goff, David C.

2009-01-01

Although the Diabetes Prevention Program (DPP) developed a lifestyle weight loss intervention that has been demonstrated to prevent type 2 diabetes in high-risk individuals, it has yet to be widely adopted at the community level. The Healthy Living Partnership to Prevent Diabetes study (HELP PD) was designed to translate the DPP approach for use in community settings as a cost-effective intervention led by Community Health Workers (CHW's) and administered through a Diabetes Care Center (DCC). Approximately 300 overweight and obese (BMI 25-40 kg/m2) individuals with prediabetes (fasting blood glucose 95-124 mg/dl) were randomly assigned to either a lifestyle weight loss intervention (LW) or an enhanced usual care comparison condition (UC). The goal of LW is ≥7% weight loss achieved through increases in physical activity (180 min/wk) and decreases in caloric intake (approximately 1500 kcal/day). The intervention consists of CHW-led group-mediated cognitive behavioral meetings that occur weekly for 6 months and monthly thereafter for 18 months. UC consists of 2 individual meetings with a registered dietitian and a monthly newsletter. The primary outcome is change in fasting blood glucose. Secondary outcomes include cardiovascular risk factors, health-related quality of life, and social cognitive variables. Outcomes are masked and are collected every 6 months. The cost-effectiveness of the program will also be assessed. A community-based program that is administered through local DCC's and that harnesses the experience of community members (CHW's) may be a promising strategy for the widespread dissemination of interventions effective at preventing type 2 diabetes in high risk individuals. PMID:19758580

Impact of Lifestyle and Metformin Interventions on the Risk of Progression to Diabetes and Regression to Normal Glucose Regulation in Overweight or Obese People With Impaired Glucose Regulation.

PubMed

Herman, William H; Pan, Qing; Edelstein, Sharon L; Mather, Kieren J; Perreault, Leigh; Barrett-Connor, Elizabeth; Dabelea, Dana M; Horton, Edward; Kahn, Steven E; Knowler, William C; Lorenzo, Carlos; Pi-Sunyer, Xavier; Venditti, Elizabeth; Ye, Wen

2017-12-01

Both lifestyle and metformin interventions can delay or prevent progression to type 2 diabetes mellitus (DM) in people with impaired glucose regulation, but there is considerable interindividual variation in the likelihood of receiving benefit. Understanding an individual's 3-year risk of progressing to DM and regressing to normal glucose regulation (NGR) might facilitate benefit-based tailored treatment. We used the values of 19 clinical variables measured at the Diabetes Prevention Program (DPP) baseline evaluation and Cox proportional hazards models to assess the 3-year risk of progression to DM and regression to NGR separately for DPP lifestyle, metformin, and placebo participants who were adherent to the interventions. Lifestyle participants who lost ≥5% of their initial body weight at 6 months and metformin and placebo participants who reported taking ≥80% of their prescribed medication at the 6-month follow-up were defined as adherent. Eleven of 19 clinical variables measured at baseline predicted progression to DM, and 6 of 19 predicted regression to NGR. Compared with adherent placebo participants at lowest risk of developing diabetes, participants at lowest risk of developing diabetes who adhered to a lifestyle intervention had an 8% absolute risk reduction (ARR) of developing diabetes and a 35% greater absolute likelihood of reverting to NGR. Participants at lowest risk of developing diabetes who adhered to a metformin intervention had no reduction in their risk of developing diabetes and a 17% greater absolute likelihood of reverting to NGR. Participants at highest risk of developing DM who adhered to a lifestyle intervention had a 39% ARR of developing diabetes and a 24% greater absolute likelihood of reverting to NGR, whereas those who adhered to the metformin intervention had a 25% ARR of developing diabetes and an 11% greater absolute likelihood of reverting to NGR. Unlike our previous analyses that sought to explain population risk, these analyses evaluate individual risk. The models can be used by overweight and obese adults with fasting hyperglycemia and impaired glucose tolerance to facilitate personalized decision-making by allowing them to explicitly weigh the benefits and feasibility of the lifestyle and metformin interventions. © 2017 by the American Diabetes Association.

Rationale and design of a comparative effectiveness trial to prevent type 2 diabetes in mothers and children: the ENCOURAGE healthy families study.

PubMed

Hannon, Tamara S; Carroll, Aaron E; Palmer, Kelly N; Saha, Chandan; Childers, Wendy K; Marrero, David G

2015-01-01

The number of youth with type 2 diabetes (T2D) is expected to quadruple over 4 decades. Gestational diabetes mellitus (GDM) is also increasing and is linked with development of T2D in women, and greater risk for T2D in adolescents exposed to GDM. Despite the increasing prevalence of T2D, approaches to prevent diabetes in high-risk youth and families are rare. To address this, we are conducting the Encourage Health Families Study (ENCOURAGE). This is a randomized trial evaluating the comparative effectiveness and costs of an adaptation of the Diabetes Prevention Program (DPP) directed at mothers who had GDM or prediabetes and their children. The intervention is a group-based lifestyle program which we developed and implemented in partnership with the YMCA. We are comparing the ENCOURAGE intervention targeted to 1) mothers who have had GDM or prediabetes, and 2) mothers who have had GDM or prediabetes along with their school-aged children. This manuscript provides 1) the rationale for a targeted approach to preventing T2D and the interventions, 2) description of the translation of the DPP curriculum, and 3) the study design and methodology. The primary aims are to determine if participation leads to 1) weight loss in high-risk mothers, and 2) youth having healthier weights and lifestyle habits. We will also evaluate costs associated with each approach. These data are essential to build a translation model of T2D prevention that is both realistic and feasible to address this growing problem in both youth and adults. Copyright © 2014 Elsevier Inc. All rights reserved.

Design of a comparative effectiveness randomized controlled trial testing a faith-based Diabetes Prevention Program (WORD DPP) vs. a Pacific culturally adapted Diabetes Prevention Program (PILI DPP) for Marshallese in the United States.

PubMed

McElfish, Pearl Anna; Long, Christopher R; Kaholokula, Joseph Keawe'aimoku; Aitaoto, Nia; Bursac, Zoran; Capelle, Lucy; Laelan, Melisa; Bing, Williamina Ioanna; Riklon, Sheldon; Rowland, Brett; Ayers, Britni L; Wilmoth, Ralph O; Langston, Krista N; Schootman, Mario; Selig, James P; Yeary, Karen Hye-Cheon Kim

2018-05-01

Pacific Islander populations, including Marshallese, face a disproportionately high burden of health disparities relative to the general population. A community-based participatory research (CBPR) approach was utilized to engage Marshallese participants in a comparative effectiveness trial testing 2 Diabetes Prevention Program (DPP) interventions designed to reduce participant's weight, lower HbA1c, encourage healthy eating, and increase physical activity. To compare the effectiveness of the faith-based (WORD) DPP to the culturally adapted (Pacific Culturally Adapted Diabetes Prevention Program [PILI]) DPP, a clustered randomized controlled trial (RCT) with 384 Marshallese participants will be implemented in 32 churches located in Arkansas, Kansas, Missouri, and Oklahoma. Churches will be randomly assigned to WORD DPP arm or to PILI DPP arm. WORD DPP focuses on connecting faith and health to attain a healthy weight, eat healthy, and be more physically active. In contrast, PILI DPP is a family and community focused DPP curriculum specifically adapted for implementation in Pacific Islander communities. PILI focuses on engaging social support networks to maintain a healthy weight, eat healthy, and be more physically active. All participants are assessed at baseline, immediate post intervention, and 12 months post intervention. Both interventions aim to cause weight loss through improving physical activity and healthy eating, with the goal of preventing the development of T2D. The clustered RCT will determine which intervention is most effective with the Marshallese population. The utilization of a CBPR approach that involves local stakeholders and engages faith-based institutions in Marshallese communities will increase the potential for success and sustainability. This study is registered at clinicaltrials.gov (NCT03270436).

Design of a comparative effectiveness randomized controlled trial testing a faith-based Diabetes Prevention Program (WORD DPP) vs. a Pacific culturally adapted Diabetes Prevention Program (PILI DPP) for Marshallese in the United States

PubMed Central

McElfish, Pearl Anna; Long, Christopher R.; Kaholokula, Joseph Keawe‘aimoku; Aitaoto, Nia; Bursac, Zoran; Capelle, Lucy; Laelan, Melisa; Bing, Williamina Ioanna; Riklon, Sheldon; Rowland, Brett; Ayers, Britni L.; Wilmoth, Ralph O.; Langston, Krista N.; Schootman, Mario; Selig, James P.; Yeary, Karen Hye-cheon Kim

2018-01-01

Abstract Background: Pacific Islander populations, including Marshallese, face a disproportionately high burden of health disparities relative to the general population. Objectives: A community-based participatory research (CBPR) approach was utilized to engage Marshallese participants in a comparative effectiveness trial testing 2 Diabetes Prevention Program (DPP) interventions designed to reduce participant's weight, lower HbA1c, encourage healthy eating, and increase physical activity. Design: To compare the effectiveness of the faith-based (WORD) DPP to the culturally adapted (Pacific Culturally Adapted Diabetes Prevention Program [PILI]) DPP, a clustered randomized controlled trial (RCT) with 384 Marshallese participants will be implemented in 32 churches located in Arkansas, Kansas, Missouri, and Oklahoma. Churches will be randomly assigned to WORD DPP arm or to PILI DPP arm. Methods: WORD DPP focuses on connecting faith and health to attain a healthy weight, eat healthy, and be more physically active. In contrast, PILI DPP is a family and community focused DPP curriculum specifically adapted for implementation in Pacific Islander communities. PILI focuses on engaging social support networks to maintain a healthy weight, eat healthy, and be more physically active. All participants are assessed at baseline, immediate post intervention, and 12 months post intervention. Summary: Both interventions aim to cause weight loss through improving physical activity and healthy eating, with the goal of preventing the development of T2D. The clustered RCT will determine which intervention is most effective with the Marshallese population. The utilization of a CBPR approach that involves local stakeholders and engages faith-based institutions in Marshallese communities will increase the potential for success and sustainability. This study is registered at clinicaltrials.gov (NCT03270436). PMID:29742712

Comprehensive Analysis of Established Dyslipidemia-Associated Loci in the Diabetes Prevention Program

PubMed Central

Varga, Tibor V.; Winters, Alexandra H.; Jablonski, Kathleen A.; Horton, Edward S.; Khare-Ranade, Prajakta; Knowler, William C.; Marcovina, Santica M.; Renström, Frida; Watson, Karol E.; Goldberg, Ronald; Florez, José C.

2016-01-01

Background We assessed whether 234 established dyslipidemia-associated loci modify the effects of metformin treatment and lifestyle intervention (vs. placebo control) on lipid and lipid sub-fraction levels in the Diabetes Prevention Program (DPP) randomized controlled trial. Methods and Results We tested gene-treatment interactions in relation to baseline adjusted follow-up blood lipid concentrations (high and low density lipoprotein cholesterol [HDL-C, LDL-C], total cholesterol, triglycerides) and lipoprotein sub-fraction particle concentrations and size in 2,993 participants with pre-diabetes. Of the previously reported SNP associations, 32.5% replicated at P<0.05 with baseline lipid traits. Trait-specific genetic risk scores (GRS) were robustly associated (3×10−4>P>1.1×10−16) with their respective baseline traits for all but two traits. Lifestyle modified the effect of the GRS for large HDL particle numbers, such that each risk allele of the GRSHDL-large was associated with lower concentrations of large HDL particles at follow-up in the lifestyle arm (β=−0.11 μmol/l per GRS risk allele; 95%CI −0.188, −0.033; P=5×10−3; Pinteraction=1×10−3 for lifestyle vs. placebo), but not in the metformin or placebo arms (P>0.05). In the lifestyle arm, participants with high genetic risk had more favorable or similar trait levels at 1-yr compared to participants at lower genetic risk at baseline for 17 of the 20 traits. Conclusions Improvements in large HDL particle concentrations conferred by lifestyle may be diminished by genetic factors. Lifestyle intervention, however, was successful in offsetting unfavorable genetic loading for most lipid traits. PMID:27784733

A Review of Technology-Assisted Interventions for Diabetes Prevention.

PubMed

Grock, Shira; Ku, Jeong-Hee; Kim, Julie; Moin, Tannaz

2017-09-23

The high prevalence of prediabetes and success of the diabetes prevention program (DPP) has led to increasing efforts to provide readily accessible, cost-effective DPP interventions to the general public. Technology-assisted DPP interventions are of particular interest since they may be easier to widely distribute and sustain as compared to traditional in-person DPP. The purpose of this article is to provide an overview of currently available technology-assisted DPP interventions. This review focuses on studies that have examined the use of mobile phone text messaging, smartphone/web-based apps, and telehealth programs to help prevent or delay the onset of incident type 2 diabetes. While there is variability in the results of studies focused on technology-assisted DPP and weight loss interventions, there is evidence to suggest that these programs have been associated with clinically meaningful weight loss and can be cost-effective. Patients who are at risk for diabetes can be offered technology-assisted DPP and weight loss interventions to lower their risk of incident diabetes. Further research should determine what specific combination of intervention features would be most successful.

Diabetes Prevention Program (DPP)

MedlinePlus

... mass index of 35 or higher. DPP Study Design The DPP was a randomized, controlled clinical trial ... by several earlier small-scale studies. DPPOS Study Design The DPPOS follow-up study started in 2002. ...

Lifestyle interventions based on the diabetes prevention program delivered via eHealth: A systematic review and meta-analysis.

PubMed

Joiner, Kevin L; Nam, Soohyun; Whittemore, Robin

2017-07-01

The objective was to describe Diabetes Prevention Program (DPP)-based lifestyle interventions delivered via electronic, mobile, and certain types of telehealth (eHealth) and estimate the magnitude of the effect on weight loss. A systematic review was conducted. PubMed and EMBASE were searched for studies published between January 2003 and February 2016 that met inclusion and exclusion criteria. An overall estimate of the effect on mean percentage weight loss across all the interventions was initially conducted. A stratified meta-analysis was also conducted to determine estimates of the effect across the interventions classified according to whether behavioral support by counselors post-baseline was not provided, provided remotely with communication technology, or face-to-face. Twenty-two studies met the inclusion/exclusion criteria, in which 26 interventions were evaluated. Samples were primarily white and college educated. Interventions included Web-based applications, mobile phone applications, text messages, DVDs, interactive voice response telephone calls, telehealth video conferencing, and video on-demand programing. Nine interventions were stand-alone, delivered post-baseline exclusively via eHealth. Seventeen interventions included additional behavioral support provided by counselors post-baseline remotely with communication technology or face-to-face. The estimated overall effect on mean percentage weight loss from baseline to up to 15months of follow-up across all the interventions was -3.98%. The subtotal estimate across the stand-alone eHealth interventions (-3.34%) was less than the estimate across interventions with behavioral support given by a counselor remotely (-4.31%), and the estimate across interventions with behavioral support given by a counselor in-person (-4.65%). There is promising evidence of the efficacy of DPP-based eHealth interventions on weight loss. Further studies are needed particularly in racially and ethnically diverse populations with limited levels of educational attainment. Future research should also focus on ways to optimize behavioral support. Copyright © 2017 Elsevier Inc. All rights reserved.

Steroid Sex Hormones, Sex Hormone-Binding Globulin, and Diabetes Incidence in the Diabetes Prevention Program.

PubMed

Mather, K J; Kim, C; Christophi, C A; Aroda, V R; Knowler, W C; Edelstein, S E; Florez, J C; Labrie, F; Kahn, S E; Goldberg, R B; Barrett-Connor, E

2015-10-01

Steroid sex hormones and SHBG may modify metabolism and diabetes risk, with implications for sex-specific diabetes risk and effects of prevention interventions. This study aimed to evaluate the relationships of steroid sex hormones, SHBG and SHBG single-nucleotide polymorphisms (SNPs) with diabetes risk factors and with progression to diabetes in the Diabetes Prevention Program (DPP). This was a secondary analysis of a multicenter randomized clinical trial involving 27 U.S. academic institutions. The study included 2898 DPP participants: 969 men, 948 premenopausal women not taking exogenous sex hormones, 550 postmenopausal women not taking exogenous sex hormones, and 431 postmenopausal women taking exogenous sex hormones. Participants were randomized to receive intensive lifestyle intervention, metformin, or placebo. Associations of steroid sex hormones, SHBG, and SHBG SNPs with glycemia and diabetes risk factors, and with incident diabetes over median 3.0 years (maximum, 5.0 y). T and DHT were inversely associated with fasting glucose in men, and estrone sulfate was directly associated with 2-hour post-challenge glucose in men and premenopausal women. SHBG was associated with fasting glucose in premenopausal women not taking exogenous sex hormones, and in postmenopausal women taking exogenous sex hormones, but not in the other groups. Diabetes incidence was directly associated with estrone and estradiol and inversely with T in men; the association with T was lost after adjustment for waist circumference. Sex steroids were not associated with diabetes outcomes in women. SHBG and SHBG SNPs did not predict incident diabetes in the DPP population. Estrogens and T predicted diabetes risk in men but not in women. SHBG and its polymorphisms did not predict risk in men or women. Diabetes risk is more potently determined by obesity and glycemia than by sex hormones.

Long-term effects of the Diabetes Prevention Program interventions on cardiovascular risk factors: a report from the DPP Outcomes Study.

PubMed

Orchard, T J; Temprosa, M; Barrett-Connor, E; Fowler, S E; Goldberg, R B; Mather, K J; Marcovina, S M; Montez, M; Ratner, R E; Saudek, C D; Sherif, H; Watson, K E

2013-01-01

Whether long-term cardiovascular risk is reduced by the Diabetes Prevention Program interventions is unknown. The aim of this study was to determine the long-term differences in cardiovascular disease risk factors and the use of lipid and blood pressure medications by the original Diabetes Prevention Program intervention group. This long-term follow-up (median 10 years, interquartile range 9.0-10.5) of the three-arm Diabetes Prevention Program randomized controlled clinical trial (metformin, intensive lifestyle and placebo), performed on 2766 (88%) of the Diabetes Prevention Program participants (who originally had impaired glucose tolerance), comprised a mean of 3.2 years of randomized treatment, approximately 1-year transition (during which all participants were offered intensive lifestyle intervention) and 5 years follow-up (Diabetes Prevention Program Outcomes Study). During the study, participants were followed in their original groups with their clinical care being provided by practitioners outside the research setting. The study determined lipoprotein profiles and blood pressure and medication use annually. After 10 years' follow-up from Diabetes Prevention Program baseline, major reductions were seen for systolic (-2 to -3) and diastolic (-6 to -6.5 mmHg) blood pressure, and for LDL cholesterol (-0.51 to -0.6 mmol/l) and triglycerides (-0.23 to -0.25 mmol/l) in all groups, with no between-group differences. HDL cholesterol also rose significantly (0.14 to 0.15 mmol/l) in all groups. Lipid (P = 0.01) and blood pressure (P = 0.09) medication use, however, were lower for the lifestyle group during the Diabetes Prevention Program Outcomes Study. Overall, intensive lifestyle intervention achieved, with less medication, a comparable long-term effect on cardiovascular disease risk factors, to that seen in the metformin and placebo groups. © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.

Effect of Long-Term Metformin and Lifestyle in the Diabetes Prevention Program and Its Outcome Study on Coronary Artery Calcium.

PubMed

Goldberg, Ronald B; Aroda, Vanita R; Bluemke, David A; Barrett-Connor, Elizabeth; Budoff, Matthew; Crandall, Jill P; Dabelea, Dana; Horton, Edward S; Mather, Kieren J; Orchard, Trevor J; Schade, David; Watson, Karol; Temprosa, Marinella

2017-07-04

Despite the reduced incidence of coronary heart disease with intensive risk factor management, people with diabetes mellitus and prediabetes remain at increased coronary heart disease risk. Diabetes prevention interventions may be needed to reduce coronary heart disease risk. This approach was examined in the DPP (Diabetes Prevention Program) and the DPPOS (Diabetes Prevention Program Outcome Study), a long-term intervention study in 3234 subjects with prediabetes (mean±SD age, 64±10 years) that showed reduced diabetes risk with lifestyle and metformin compared with placebo over 3.2 years. The DPPOS offered periodic group lifestyle sessions to all participants and continued metformin in the originally randomized metformin group. Subclinical atherosclerosis was assessed in 2029 participants with coronary artery calcium (CAC) measurements after an average of 14 years of follow-up. The CAC scores were analyzed continuously as CAC severity and categorically as CAC presence (CAC score >0) and reported separately in men and women. There were no CAC differences between lifestyle and placebo intervention groups in either sex. CAC severity and presence were significantly lower among men in the metformin versus the placebo group (age-adjusted mean CAC severity, 39.5 versus 66.9 Agatston units, P =0.04; CAC presence, 75% versus 84%, P =0.02), but no metformin effect was seen in women. In multivariate analysis, the metformin effect in men was not influenced by demographic, anthropometric, or metabolic factors; by the development of diabetes mellitus; or by use/nonuse of statin therapy. Metformin may protect against coronary atherosclerosis in prediabetes and early diabetes mellitus among men. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00038727. © 2017 American Heart Association, Inc.

Implementation of the YMCA Diabetes Prevention Program throughout an Integrated Health System: A Translational Study.

PubMed

Adams, Ron; Hebert, Christopher J; Mcvey, Linda; Williams, Roger

2016-01-01

HealthSpan Physicians (HSP), an integrated medical system in Northeast Ohio, partnered with the Young Men's Christian Association (YMCA) of Greater Cleveland to implement a referral system for the evidence-based Diabetes Prevention Program (DPP) throughout HSP. The YMCA of USA employs a cost-effective, customized version of the original DPP in which coaches take the place of in-house clinical staff. Efficacy of the YMCA DPP was shown earlier in the DEPLOY Study. To improve outcomes of metrics used in the DEPLOY Study. Observational study focusing on engagement, persistence, recruitment, and adherence to the DPP. In August 2014, HSP mailed an invitation to 2200 patients identified as both Medicare eligible and at risk of prediabetes to attend no-obligation information sessions about the DPP. After these sessions, YMCA staff called interested participants and asked them to enroll in and to commit to the program. Motivation and reinforcement were provided to patients through YMCA-provided signs, brochures, and posters; the HSP Web site; and in-person conversations with primary care physicians. Average weight loss at the end of 16 weeks in the program and average retention through Session 9. Of the 2200 patients contacted, 351 (16.0%) responded by attending the information session, and 228 enrolled in the YMCA DPP (11.3%) and persisted through at least Week 9. This result is an improvement over the 1.7% of eligible enrollees who responded to the DEPLOY Study's mailing. A marketing approach to implementing the YMCA DPP in an integrated medical system results in excellent outcomes.

A comparison of categorization criteria used to define successful weight loss maintainers and regainers in the Look AHEAD and DPP trials

USDA-ARS?s Scientific Manuscript database

Introduction: While a variety of lifestyle interventions have resulted in successful weight loss, effective strategies to maintain weight loss are lacking, with many interventions reporting high rates of regain. Identifying characteristics of individuals who successfully maintained their weight afte...

Prevention of type 2 diabetes in urban American Indian/Alaskan Native communities: The Life in BALANCE pilot study

PubMed Central

Benyshek, Daniel C.; Chino, Michelle; Dodge-Francis, Carolee; Begay, Toricellas O.; Jin, Hongbin; Giordano, Celeste

2014-01-01

Objective The Life in BALANCE (LIB) study is a pilot translational study modeling the Diabetes Prevention Program (DPP) intensive lifestyle coaching intervention among an underserved, high-risk population: American Indians/Alaska Natives (AI/ANs) living in a large urban setting (Las Vegas, Nevada). Research Design and Methods A total of 22 overweight/obese AI/ANs (age, 39.6 ± 10.4 years; BMI, 34.1 ± 6.3 kg/m2) at increased risk for developing type 2 diabetes (HbA1c > 5.4 (36 mmol/mol) < 6.4 percent (46 mmol/mol) participated in the program between April and December, 2011. Study participants completed a 16 week intensive lifestyle coaching intervention. In addition to obtaining qualitative data regarding opportunities and challenges of applying the lifestyle intervention for AI/AN participants in an urban setting, clinical data, including BMI, waist circumference, blood pressure, fasting blood glucose, and blood lipids (HDL, LDL and Triglycerides), were collected. Results Only 12 of the 22 participants remained in the LIB program at the final post-program follow-up. Participants demonstrated significant decreased waist circumference and elevated HDL cholesterol. Triglycerides manifested the highest percentage change without statistical significance. No significant change was observed in blood pressure or fasting blood glucose. Conclusions LIB participants’ improvements in BMI, waist circumference, HDL cholesterol and triglycerides suggests type 2 diabetes prevention programs aimed at urban AI/ANs show significant potential for reducing the risk of developing type 2 diabetes among this underserved and high risk community. Qualitative data suggest the main challenge for type 2 diabetes prevention specific to this population is a need for improved community outreach strategies. PMID:24634801

Metabolite Profiles of Diabetes Incidence and Intervention Response in the Diabetes Prevention Program

PubMed Central

Ma, Yong; Clish, Clary; Florez, Jose C.; Wang, Thomas J.; Gerszten, Robert E.

2016-01-01

Identifying novel biomarkers of type 2 diabetes risk may improve prediction and prevention among individuals at high risk of the disease and elucidate new biological pathways relevant to diabetes development. We performed plasma metabolite profiling in the Diabetes Prevention Program (DPP), a completed trial that randomized high-risk individuals to lifestyle, metformin, or placebo interventions. Previously reported markers, branched-chain and aromatic amino acids and glutamine/glutamate, were associated with incident diabetes (P < 0.05 for all), but these associations were attenuated upon adjustment for clinical and biochemical measures. By contrast, baseline levels of betaine, also known as glycine betaine (hazard ratio 0.84 per SD log metabolite level, P = 0.02), and three other metabolites were associated with incident diabetes even after adjustment. Moreover, betaine was increased by the lifestyle intervention, which was the most effective approach to preventing diabetes, and increases in betaine at 2 years were also associated with lower diabetes incidence (P = 0.01). Our findings indicate betaine is a marker of diabetes risk among high-risk individuals both at baseline and during preventive interventions and they complement animal models demonstrating a direct role for betaine in modulating metabolic health. PMID:26861782

A High-Carbohydrate, High-Fiber, Low-Fat Diet Results in Weight Loss among Adults at High Risk of Type 2 Diabetes.

PubMed

Sylvetsky, Allison C; Edelstein, Sharon L; Walford, Geoffrey; Boyko, Edward J; Horton, Edward S; Ibebuogu, Uzoma N; Knowler, William C; Montez, Maria G; Temprosa, Marinella; Hoskin, Mary; Rother, Kristina I; Delahanty, Linda M

2017-11-01

Background: Weight loss is a key factor in reducing diabetes risk. The Diabetes Prevention Program (DPP) is a completed clinical trial that randomly assigned individuals at high risk of diabetes to a placebo (PLBO), metformin (MET), or intensive lifestyle intervention (ILS) group, which included physical activity (PA) and reduced dietary fat intake. Objective: We aimed to evaluate the associations between diet and weight at baseline and to identify specific dietary factors that predicted weight loss among DPP participants. Methods: Diet was assessed by a food frequency questionnaire. The associations between intakes of macronutrients and various food groups and body weight among DPP participants at baseline were assessed by linear regression, adjusted for race/ethnicity, age, sex, calorie intake, and PA. Models that predicted weight loss at year 1 were adjusted for baseline weight, change in calorie intake, and change in PA and stratified by treatment allocation (MET, ILS, and PLBO). All results are presented as estimates ± SEs. Results: A total of 3234 participants were enrolled in the DPP; 2924 had completed dietary data (67.5% women; mean age: 50.6 ± 10.7 y). Adjusted for calorie intake, baseline weight was negatively associated with carbohydrate intake (-1.14 ± 0.18 kg body weight/100 kcal carbohydrate, P < 0.0001) and, specifically, dietary fiber (-1.26 ± 0.28 kg/5 g fiber, P < 0.0001). Baseline weight was positively associated with total fat (1.25 ± 0.21 kg/100 kcal, P < 0.0001), saturated fat (1.96 ± 0.46 kg/100 kcal, P < 0.0001), and protein (0.21 ± 0.05 kg/100 kcal, P < 0.0001). For all groups, weight loss after 1 y was associated with increases in carbohydrate intake, specifically dietary fiber, and decreases in total fat and saturated fat intake. Conclusions: Higher carbohydrate consumption among DPP participants, specifically high-fiber carbohydrates, and lower total and saturated fat intake best predicted weight loss when adjusted for changes in calorie intake. Our results support the benefits of a high-carbohydrate, high-fiber, low-fat diet in the context of overall calorie reduction leading to weight loss, which may prevent diabetes in high-risk individuals. This trial was registered at clinicaltrials.gov as NCT00004992. © 2017 American Society for Nutrition.

The effects of GLP-1 analogues, DPP-4 inhibitors and SGLT2 inhibitors on the renal system.

PubMed

Schernthaner, Guntram; Mogensen, Carl Erik; Schernthaner, Gerit-Holger

2014-09-01

Diabetic nephropathy (DN) affects an estimated 20%-40% of patients with type 2 diabetes mellitus (T2DM). Key modifiable risk factors for DN are albuminuria, anaemia, dyslipidaemia, hyperglycaemia and hypertension, together with lifestyle factors, such as smoking and obesity. Early detection and treatment of these risk factors can prevent DN or slow its progression, and may even induce remission in some patients. DN is generally preceded by albuminuria, which frequently remains elevated despite treatment in patients with T2DM. Optimal treatment and prevention of DN may require an early, intensive, multifactorial approach, tailored to simultaneously target all modifiable risk factors. Regular monitoring of renal function, including urinary albumin excretion, creatinine clearance and glomerular filtration rate, is critical for following any disease progression and making treatment adjustments. Dipeptidyl peptidase (DPP)-4 inhibitors and sodium-glucose cotransporter 2 (SGLT2) inhibitors lower blood glucose levels without additional risk of hypoglycaemia, and may also reduce albuminuria. Further investigation of the potential renal benefits of DPP-4 and SGLT2 inhibitors is underway. © The Author(s) 2014.

The effects of GLP-1 analogues, DPP-4 inhibitors and SGLT2 inhibitors on the renal system

PubMed Central

Mogensen, Carl Erik; Schernthaner, Gerit-Holger

2014-01-01

Diabetic nephropathy (DN) affects an estimated 20%–40% of patients with type 2 diabetes mellitus (T2DM). Key modifiable risk factors for DN are albuminuria, anaemia, dyslipidaemia, hyperglycaemia and hypertension, together with lifestyle factors, such as smoking and obesity. Early detection and treatment of these risk factors can prevent DN or slow its progression, and may even induce remission in some patients. DN is generally preceded by albuminuria, which frequently remains elevated despite treatment in patients with T2DM. Optimal treatment and prevention of DN may require an early, intensive, multifactorial approach, tailored to simultaneously target all modifiable risk factors. Regular monitoring of renal function, including urinary albumin excretion, creatinine clearance and glomerular filtration rate, is critical for following any disease progression and making treatment adjustments. Dipeptidyl peptidase (DPP)-4 inhibitors and sodium-glucose cotransporter 2 (SGLT2) inhibitors lower blood glucose levels without additional risk of hypoglycaemia, and may also reduce albuminuria. Further investigation of the potential renal benefits of DPP-4 and SGLT2 inhibitors is underway. PMID:25116004

Reliability of techniques used in the diagnosis of canine visceral leishmaniasis by the national control program in Brazil: A survey in an area of recent transmission.

PubMed

Belo, Vinícius Silva; Gregório, Eliana Aparecida; Teixeira-Neto, Rafael Gonçalves; da Rocha Lima, Ana Cristina Vianna Mariano; Pereira, Agnes Antônia Sampaio; Marcelino, Andreza Pain; Paz, Gustavo Fontes; da Silva, Eduardo Sérgio

2017-10-01

One of the key components of the Brazilian Program for the Control of Visceral Leishmaniasis (PCLV) is the euthanasia of Leishmania-infected canine reservoirs, the detection of which depends on a screening procedure involving a Dual Path Platform ® (DPP) immunoassay and a confirmatory enzyme-linked immunosorbent assay (ELISA). The aims of the present study were to evaluate the reliability of these techniques in a region of recent transmission of canine VL, to follow up the seroconversion 3-4 months after the initial diagnosis of DPP reactive but ELISA indeterminate or non-reactive dogs, and to identify the species of Leishmania in circulation in the area. Each animal was submitted to DPP under field conditions, performed by municipal health workers using peripheral blood (DPP-field), to DPP under laboratory conditions using serum (DPP-lab) and to ELISA using serum. The agreements between the tests were determined using McNemar's χ 2 test, Cohen's kappa coefficient (k) at the 95% confidence interval and prevalence-adjusted bias-adjusted kappa (PABAK). Of the 1130 dogs examined, 74.2% were non-reactive in all three tests applied. Based on the PCLV positive-infection criterion, seroprevalence was 8.9% (101/1130) with 83.2% (84/101) of infected animals showing reactivity in all three tests while 7.8% (8/101) were reactive in DPP-field and ELISA and 8.9% (9/101) in DPP-lab and ELISA. The proportions of disagreements were substantial in all comparisons. Inter-rater reliability between DPP-field and ELISA (k=0.55; PABAK=0.78) and DPP-lab and ELISA (k=0.59; PABAK=0.81) were considered moderate, while that between DPP-field and DPP-lab (k=0.61; PABAK=0.79) was classified as marginally good. The proportion of seroconversions in DPP reactive animals that were initially ELISA indeterminate was significantly higher than in those that were DPP reactive but initially ELISA non-reactive. Restriction fragment length polymorphism analysis revealed the presence of Leishmania infantum, the etiologic agent of VL, in bone marrow samples from VL-infected animals. Our data showed that the techniques and protocols currently employed in the PCLV screening approach are not entirely reliable. Further consideration should be given to monitoring dogs with undetermined results in ELISA and a better training should be provided for health workers responsible for performing DPP tests applied under field conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluating the Effects of Scripted Distributed Pair Programming on Student Performance and Participation

ERIC Educational Resources Information Center

Tsompanoudi, Despina; Satratzemi, Maya; Xinogalos, Stelios

2016-01-01

The results presented in this paper contribute to research on two different areas of teaching methods: distributed pair programming (DPP) and computer-supported collaborative learning (CSCL). An evaluation study of a DPP system that supports collaboration scripts was conducted over one semester of a computer science course. Seventy-four students…

Usefulness of a Novel Mobile Diabetes Prevention Program Delivery Platform With Human Coaching: 65-Week Observational Follow-Up

PubMed Central

Michaelides, Andreas; Major, Jennifer; Pienkosz Jr, Edmund; Wood, Meghan; Kim, Youngin

2018-01-01

Background It is widely recognized that the prevalence of obesity and comorbidities including prediabetes and type 2 diabetes continue to increase worldwide. Results from a 24-week Diabetes Prevention Program (DPP) fully mobile pilot intervention were previously published showing promising evidence of the usefulness of DPP-based eHealth interventions on weight loss. Objective This pilot study extends previous findings to evaluate weight loss results of core (up to week 16) and maintenance (postcore weeks) DPP interventions at 65 weeks from baseline. Methods Originally, 140 participants were invited and 43 overweight or obese adult participants with a diagnosis of prediabetes signed up to receive a 24-week virtual DPP with human coaching through a mobile platform. At 65 weeks, this pilot study evaluates weight loss and engagement in maintenance participants by means of repeated measures analysis of variances and backward multiple linear regression to examine predictors of weight loss. Last observation carried forward was used for endpoint measurements. Results At 65 weeks, mean weight loss was 6.15% in starters who read 1 or more lessons per week on 4 or more core weeks, 7.36% in completers who read 9 or more lessons per week on core weeks, and 8.98% in maintenance completers who did any action in postcore weeks (all P<.001). Participants were highly engaged, with 80% (47/59) of the sample completing 9 lessons or more and 69% (32/47) of those completing the maintenance phase. In-app actions related to self-monitoring significantly predicted weight loss. Conclusions In comparison to eHealth programs, this pilot study shows that a fully mobile DPP can produce transformative weight loss. A fully mobile DPP intervention resulted in significant weight loss and high engagement during the maintenance phase, providing evidence for long-term potential as an alternative to in-person DPP by removing many of the barriers associated with in-person and other forms of virtual DPP. PMID:29724709

Menopause and risk of diabetes in the Diabetes Prevention Program

PubMed Central

Kim, Catherine; Edelstein, Sharon L.; Crandall, Jill P.; Dabelea, Dana; Kitabchi, Abbas E.; Hamman, Richard F.; Montez, Maria G.; Perreault, Leigh; Foulkes, Mary A.; Barrett-Connor, Elizabeth

2012-01-01

Objective The study objective was to examine the association between menopause status and diabetes risk among women with glucose intolerance and to determine if menopausal status modifies response to diabetes prevention interventions. Methods The study population included women in premenopause (n=708), natural postmenopause (n=328), and bilateral oophorectomy (n=201) in the Diabetes Prevention Program (DPP), a randomized placebo-controlled trial of lifestyle intervention and metformin among glucose intolerant adults. Associations between menopause and diabetes risk were evaluated using Cox proportional hazard models that adjusted for demographic variables (age, race/ethnicity, family history of diabetes, history of gestational diabetes mellitus), waist circumference, insulin resistance and corrected insulin response. Similar models were constructed after stratification by menopause type and hormone therapy (HT) use. Results After adjustment for age, there was no association between natural menopause or bilateral oophorectomy and diabetes risk. Differences by study arm were observed in women who reported bilateral oophorectomy. In the lifestyle arm, women with bilateral oophorectomy had a lower adjusted hazard for diabetes (HR 0.19, 95% CI 0.04, 0.94), although observations were too few to determine if this was independent of HT use. No significant differences were seen in the metformin (HR 1.29, 95% CI 0.63, 2.64) or placebo arms (HR 1.37, 95% CI 0.74, 2.55). Conclusions Among women at high-risk for diabetes, natural menopause was not associated with diabetes risk and did not affect response to diabetes prevention interventions. In the lifestyle intervention, bilateral oophorectomy was associated with decreased diabetes risk. PMID:21709591

Usefulness of a Novel Mobile Diabetes Prevention Program Delivery Platform With Human Coaching: 65-Week Observational Follow-Up.

PubMed

Michaelides, Andreas; Major, Jennifer; Pienkosz, Edmund; Wood, Meghan; Kim, Youngin; Toro-Ramos, Tatiana

2018-05-03

It is widely recognized that the prevalence of obesity and comorbidities including prediabetes and type 2 diabetes continue to increase worldwide. Results from a 24-week Diabetes Prevention Program (DPP) fully mobile pilot intervention were previously published showing promising evidence of the usefulness of DPP-based eHealth interventions on weight loss. This pilot study extends previous findings to evaluate weight loss results of core (up to week 16) and maintenance (postcore weeks) DPP interventions at 65 weeks from baseline. Originally, 140 participants were invited and 43 overweight or obese adult participants with a diagnosis of prediabetes signed up to receive a 24-week virtual DPP with human coaching through a mobile platform. At 65 weeks, this pilot study evaluates weight loss and engagement in maintenance participants by means of repeated measures analysis of variances and backward multiple linear regression to examine predictors of weight loss. Last observation carried forward was used for endpoint measurements. At 65 weeks, mean weight loss was 6.15% in starters who read 1 or more lessons per week on 4 or more core weeks, 7.36% in completers who read 9 or more lessons per week on core weeks, and 8.98% in maintenance completers who did any action in postcore weeks (all P<.001). Participants were highly engaged, with 80% (47/59) of the sample completing 9 lessons or more and 69% (32/47) of those completing the maintenance phase. In-app actions related to self-monitoring significantly predicted weight loss. In comparison to eHealth programs, this pilot study shows that a fully mobile DPP can produce transformative weight loss. A fully mobile DPP intervention resulted in significant weight loss and high engagement during the maintenance phase, providing evidence for long-term potential as an alternative to in-person DPP by removing many of the barriers associated with in-person and other forms of virtual DPP. ©Andreas Michaelides, Jennifer Major, Edmund Pienkosz Jr, Meghan Wood, Youngin Kim, Tatiana Toro-Ramos. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 03.05.2018.

Association between body weight and composition and plasma 25-hydroxyvitamin D level in the Diabetes Prevention Program.

PubMed

Ceglia, Lisa; Nelson, Jason; Ware, James; Alysandratos, Konstantinos-Dionysios; Bray, George A; Garganta, Cheryl; Nathan, David M; Hu, Frank B; Dawson-Hughes, Bess; Pittas, Anastassios G

2017-02-01

We examined associations between body weight and plasma 25-hydroxyvitamin D concentration (25OHD) in prediabetes and sought to estimate the impact of adiposity on these associations. The study was conducted in the placebo (n = 1082) and intensive lifestyle (n = 1079) groups of the Diabetes Prevention Program (DPP), a multicenter trial to prevent type 2 diabetes in adults with prediabetes. Weight and 25OHD were measured at baseline, month 6, years 1 and 2. In a subset (n = 584), visceral (VAT) and subcutaneous (SAT) adiposity were assessed by computed tomography at baseline and year 1. In cross-sectional analyses, baseline body weight, total fat, VAT, and SAT were inversely associated with plasma 25OHD concentration after multivariable adjustment. VAT accounted for 40 % [95 % CI 11, 69] of the association of body weight with plasma 25OHD concentration. There was no significant contribution by total fat or SAT. Two-year changes in plasma 25OHD concentration varied inversely with changes in body weight (p < 0.0001). One-year changes in total fat, VAT, or SAT were not significant mediators of the association between change in plasma 25OHD concentration and body weight. Our study found an inverse association between body weight and plasma 25OHD concentration at baseline and over a 2-year period in adults with prediabetes. These findings in the DPP, a weight loss intervention study, raise the possibility that weight loss increases plasma 25OHD concentration. Whether adiposity mediates this association remains inconclusive.

Association between body weight and composition and plasma 25-hydroxyvitamin D level in the Diabetes Prevention Program

PubMed Central

CEGLIA, LISA; NELSON, JASON; WARE, JAMES; ALYSANDRATOS, KONSTANTINOS-DIONYSIOS; BRAY, GEORGE A.; GARGANTA, CHERYL; NATHAN, DAVID M.; HU, FRANK B; DAWSON-HUGHES, BESS; PITTAS, ANASTASSIOS G.

2016-01-01

Objective We examined associations between body weight and plasma 25-hydroxyvitamin D concentration (25OHD) in pre-diabetes and sought to estimate the impact of adiposity on these associations. Methods The study was conducted in the placebo (n=1,082) and intensive lifestyle (n=1,079) groups of the Diabetes Prevention Program (DPP), a multicenter trial to prevent type 2 diabetes in adults with pre-diabetes. Weight and 25OHD were measured at baseline, month 6, years 1 and 2. In a subset (n=584), visceral [VAT] and subcutaneous [SAT] adiposity were assessed by computed tomography at baseline and year 1. Results In cross-sectional analyses, baseline body weight, total fat, VAT, and SAT were inversely associated with plasma 25OHD concentration after multivariable adjustment. VAT accounted for 40% [95% CI 11, 69] of the association of body weight with plasma 25OHD concentration. There was no significant contribution by total fat or SAT. Two-year changes in plasma 25OHD concentration varied inversely with changes in body weight (p<0.0001). One-year changes in total fat, VAT, or SAT were not significant mediators of the association between change in plasma 25OHD concentration and body weight. Conclusion Our study found an inverse association between body weight and plasma 25OHD concentration at baseline and over a 2-year period in adults with pre-diabetes. These findings in the DPP, a weight loss intervention study, raise the possibility that weight loss increases plasma 25OHD concentration. Whether adiposity mediates this association remains inconclusive. PMID:26525562

Metabolite Profiles of Diabetes Incidence and Intervention Response in the Diabetes Prevention Program.

PubMed

Walford, Geoffrey A; Ma, Yong; Clish, Clary; Florez, Jose C; Wang, Thomas J; Gerszten, Robert E

2016-05-01

Identifying novel biomarkers of type 2 diabetes risk may improve prediction and prevention among individuals at high risk of the disease and elucidate new biological pathways relevant to diabetes development. We performed plasma metabolite profiling in the Diabetes Prevention Program (DPP), a completed trial that randomized high-risk individuals to lifestyle, metformin, or placebo interventions. Previously reported markers, branched-chain and aromatic amino acids and glutamine/glutamate, were associated with incident diabetes (P < 0.05 for all), but these associations were attenuated upon adjustment for clinical and biochemical measures. By contrast, baseline levels of betaine, also known as glycine betaine (hazard ratio 0.84 per SD log metabolite level, P = 0.02), and three other metabolites were associated with incident diabetes even after adjustment. Moreover, betaine was increased by the lifestyle intervention, which was the most effective approach to preventing diabetes, and increases in betaine at 2 years were also associated with lower diabetes incidence (P = 0.01). Our findings indicate betaine is a marker of diabetes risk among high-risk individuals both at baseline and during preventive interventions and they complement animal models demonstrating a direct role for betaine in modulating metabolic health. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Translating the Diabetes Prevention Program into practice: a review of community interventions.

PubMed

Jackson, Lindsey

2009-01-01

The purpose of this review is to summarize community interventions based on the National Institutes of Health (NIH) Diabetes Prevention Program (DPP) curriculum and to describe differences in curriculum and its effect on outcome measurements. A keyword search of PubMed and review of citation lists of relevant articles yielded 161 articles. Primary outcomes of interest were achievement of the DPP study goals: 5% to 7% loss of body weight and increased moderate physical activity to at least 150 minutes per week. A secondary outcome of improvement in metabolic syndrome components was also included. Inclusion criteria included application of a DPP-based curriculum to a community setting and publication in English. Seven articles were included in the review. Interventions were conducted across a variety of settings. All showed a significant amount of weight loss immediately following a DPP-based curriculum, varying in length from 6 to 24 weeks. Three held significance by 12 months. Two articles reported on physical activity improvements. Two articles reported improvement in metabolic syndrome components. Although the most effective intervention for type 2 diabetes prevention may not yet be identified, DPP-based interventions show promise for long-term sustainability. The DPP intervention is effective in treating overweight and obesity across a variety of settings and thus may prevent chronic diseases in which overweight and obesity are risk factors. Public health practitioners can use this successful intervention to help individuals lead healthier lives.

Linking High Risk Postpartum Women with a Technology Enabled Health Coaching Program to Reduce Diabetes Risk and Improve Wellbeing: Program Description, Case Studies, and Recommendations for Community Health Coaching Programs

PubMed Central

Thomas, Melanie; Delgadillo-Duenas, Adriana T.; Leong, Karen; Najmabadi, Adriana; Harleman, Elizabeth; Rios, Christina; Quan, Judy; Soria, Catalina; Handley, Margaret A.

2016-01-01

Background. Low-income minority women with prior gestational diabetes mellitus (pGDM) or high BMIs have increased risk for chronic illnesses postpartum. Although the Diabetes Prevention Program (DPP) provides an evidence-based model for reducing diabetes risk, few community-based interventions have adapted this program for pGDM women. Methods. STAR MAMA is an ongoing randomized control trial (RCT) evaluating a hybrid HIT/Health Coaching DPP-based 20-week postpartum program for diabetes prevention compared with education from written materials at baseline. Eligibility includes women 18–39 years old, ≥32 weeks pregnant, and GDM or BMI > 25. Clinic- and community-based recruitment in San Francisco and Sonoma Counties targets 180 women. Sociodemographic and health coaching data from a preliminary sample are presented. Results. Most of the 86 women included to date (88%) have GDM, 80% were identified as Hispanic/Latina, 78% have migrant status, and most are Spanish-speaking. Women receiving the intervention indicate high engagement, with 86% answering 1+ calls. Health coaching callbacks last an average of 9 minutes with range of topics discussed. Case studies presented convey a range of emotional, instrumental, and health literacy-related supports offered by health coaches. Discussion. The DPP-adapted HIT/health coaching model highlights the possibility and challenge of delivering DPP content to postpartum women in community settings. This trial is registered with ClinicalTrials.gov NCT02240420. PMID:27830157

Linking High Risk Postpartum Women with a Technology Enabled Health Coaching Program to Reduce Diabetes Risk and Improve Wellbeing: Program Description, Case Studies, and Recommendations for Community Health Coaching Programs.

PubMed

Athavale, Priyanka; Thomas, Melanie; Delgadillo-Duenas, Adriana T; Leong, Karen; Najmabadi, Adriana; Harleman, Elizabeth; Rios, Christina; Quan, Judy; Soria, Catalina; Handley, Margaret A

2016-01-01

Background . Low-income minority women with prior gestational diabetes mellitus (pGDM) or high BMIs have increased risk for chronic illnesses postpartum. Although the Diabetes Prevention Program (DPP) provides an evidence-based model for reducing diabetes risk, few community-based interventions have adapted this program for pGDM women. Methods . STAR MAMA is an ongoing randomized control trial (RCT) evaluating a hybrid HIT/Health Coaching DPP-based 20-week postpartum program for diabetes prevention compared with education from written materials at baseline. Eligibility includes women 18-39 years old, ≥32 weeks pregnant, and GDM or BMI > 25. Clinic- and community-based recruitment in San Francisco and Sonoma Counties targets 180 women. Sociodemographic and health coaching data from a preliminary sample are presented. Results . Most of the 86 women included to date (88%) have GDM, 80% were identified as Hispanic/Latina, 78% have migrant status, and most are Spanish-speaking. Women receiving the intervention indicate high engagement, with 86% answering 1+ calls. Health coaching callbacks last an average of 9 minutes with range of topics discussed. Case studies presented convey a range of emotional, instrumental, and health literacy-related supports offered by health coaches. Discussion . The DPP-adapted HIT/health coaching model highlights the possibility and challenge of delivering DPP content to postpartum women in community settings. This trial is registered with ClinicalTrials.gov NCT02240420.

Depressive symptoms, antidepressant medication use and new onset of diabetes in participants of the Diabetes Prevention Program and the Diabetes Prevention Program Outcomes Study

PubMed Central

Marrero, David G.; Ma, Yong; de Groot, Mary; Horton, Edward S.; Price, David W.; Barrett-Connor, Elizabeth; Carnethon, Mercedes R.; Knowler, William C.

2015-01-01

Objective To assess in participants in the Diabetes Prevention Program and Diabetes Prevention Program Outcomes Study (DPP/DPPOS) whether diagnosis of diabetes predicted: elevated depressive symptoms (DS) or antidepressant medicine (ADM) use after diagnosis; diabetes status or duration had significant effect on DS or ADM use; and associations between A1C, fasting plasma glucose (FPG), normalization of FPG and DS or ADM use post diagnosis. Methods DPP participants in 3 treatment arms [intensive lifestyle (ILS), metformin (MET), placebo (PLC)] were assessed semiannually or annually for diabetes, glucose control, ADM use, and DS. DS was measured using Beck Depression Inventory (BDI) questionnaire. Among the total 3234 enrolled participants, 1285 developed diabetes whose levels of depression were measured before and after their diabetes diagnosis. Results Neither DS nor ADM use increased significantly following diabetes diagnosis. After diabetes diagnosis, higher FPG was associated with greater ADM use in the ILS arm independent of potential confounders; a 10 mg/dl higher in FPG is associated with 8.8% more odds of ADM use. Higher FPG, and higher A1C were associated with higher BDI scores in all three arms. On average, a participant with 10 mg/dl higher rise in FPG had a 0.07 increase in BDI score. Similarly, 1% higher A1c was associated with a 0.21 point increase in BDI score. On contrary, normalization of FPG was associated with lower BDI scores. In participants with FPG that had normalized, there was a decrease of 0.30 points in the BDI score compared to those whose FPG had not normalized. Conclusions Contrary to clinical attributions, the diagnosis of diabetes did not show an immediate impact on BDI scores or ADM use. However, higher glucose levels after diagnosis were associated with small but significant higher BDI score and more ADM use. PMID:25775165

Primary care physicians' utilization of type 2 diabetes screening guidelines and referrals to behavioral interventions: a survey-linked retrospective study.

PubMed

Mehta, Sandhya; Mocarski, Michelle; Wisniewski, Tami; Gillespie, Karin; Narayan, K M Venkat; Lang, Kathleen

2017-01-01

To assess primary care physicians' (PCPs) knowledge of type 2 diabetes screening guidelines (American Diabetes Association (ADA) and 2008 US Preventive Services Task Force (USPSTF)), the alignment between their self-reported adherence and actual practice, and how often PCPs recommended diabetes prevention and self-management education programs (DPP/DSME). An online survey of PCPs to understand knowledge and adherence toward use of USPSTF/ADA guidelines and recommendation of DPP/DSME. Patient data from electronic medical records (EMRs) for each PCP were used to identify rates of screening in eligible patients as per guidelines and the two sources were compared to assess concordance. Of 305 surveyed physicians, 38% reported use of both guidelines (33% use ADA only, 25% USPSTF only). Approximately one-third of physicians who reported use of USPSTF/ADA guidelines had non-concordant EMR data. Similarly, while most PCPs reported they are 'very likely' to screen patients with risk factors listed in guidelines, for each criterion at least one-fourth (24%) of PCPs survey responses were non-concordant with EMRs. PCPs reported they provide referral to DPP and DSME on average to 45% and 67% of their newly diagnosed patients with pre-diabetes and diabetes, respectively. Findings show disconnect between PCPs' perceptions of adherence to screening guidelines and actual practice, and highlight limited referrals to DPP/DSME programs. More research is needed to understand barriers to guideline consistent screening and uptake of DPP/DSME, particularly in light of recent policy changes such as the linking USPSTF criteria to reimbursement and expected Medicare DPP reimbursement in 2018.

Pyroptosis and Apoptosis Pathways Engage in Bidirectional Crosstalk in Monocytes and Macrophages.

PubMed

Taabazuing, Cornelius Y; Okondo, Marian C; Bachovchin, Daniel A

2017-04-20

Pyroptosis is a lytic form of programmed cell death mediated by the inflammatory caspase-1, -4, and -5. We recently discovered that small-molecule inhibitors of the serine peptidases DPP8 and DPP9 (DPP8/9) induce pro-caspase-1-dependent pyroptosis in monocytes and macrophages. Notably, DPP8/9 inhibitors, unlike microbial agents, absolutely require caspase-1 to induce cell death. Therefore, DPP8/9 inhibitors are useful probes to study caspase-1 in cells. Here, we show that, in the absence of the pyroptosis-mediating substrate gasdermin D (GSDMD), caspase-1 activates caspase-3 and -7 and induces apoptosis, demonstrating that GSDMD is the only caspase-1 substrate that induces pyroptosis. Conversely, we found that, during apoptosis, caspase-3/-7 specifically block pyroptosis by cleaving GSDMD at a distinct site from the inflammatory caspases that inactivates the protein. Overall, this work reveals bidirectional crosstalk between apoptosis and pyroptosis in monocytes and macrophages, further illuminating the complex interplay between cell death pathways in the innate immune system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Scaffold-hopping from xanthines to tricyclic guanines: A case study of dipeptidyl peptidase 4 (DPP4) inhibitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pissarnitski, Dmitri A.; Zhao, Zhiqiang; Cole, David

2016-11-01

Molecular modeling of unbound tricyclic guanine scaffolds indicated that they can serve as effective bioisosteric replacements of xanthines. This notion was further confirmed by a combination of X-ray crystallography and SAR studies, indicating that tricyclic guanine DPP4 inhibitors mimic the binding mode of xanthine inhibitors, exemplified by linagliptin. Realization of the bioisosteric relationship between these scaffolds potentially will lead to a wider application of cyclic guanines as xanthine replacements in drug discovery programs for a variety of biological targets. Newly designed DPP4 inhibitors achieved sub-nanomolar potency range and demonstrated oral activity in vivo in mouse glucose tolerance test.

Society for Health Psychology (APA Division 38) and Society of Behavioral Medicine joint position statement on the Medicare Diabetes Prevention Program.

PubMed

Fitzpatrick, Stephanie L; Wilson, Dawn K; Pagoto, Sherry L

2017-06-01

Beginning in January 2018, the Centers for Medicare and Medicaid Services (CMS) plans to cover the Diabetes Prevention Program (DPP), also referred to as Medicare DPP. The American Psychological Association Society for Health Psychology (SfHP) and the Society for Behavioral Medicine (SBM) reviewed the proposed plan. SfHP and SBM are in support of the CMS decision to cover DPP for Medicare beneficiaries but have a significant concern that aspects of the proposal will limit the public health impact. Concerns include the emphasis on weight outcomes to determine continued coverage and the lack of details regarding requirements for coaches. SfHP and SBM are in strong support of modifications to the proposal that would remove the minimum weight loss stipulation to determine coverage and to specify type and qualifications of "coaches."

Unravelling the immunological roles of dipeptidyl peptidase 4 (DPP4) activity and/or structure homologue (DASH) proteins

PubMed Central

Klemann, C.; Stephan, M.

2016-01-01

Summary Dipeptidyl peptidase (DPP) 4 (CD26, DPP4) is a multi‐functional protein involved in T cell activation by co‐stimulation via its association with adenosine deaminase (ADA), caveolin‐1, CARMA‐1, CD45, mannose‐6‐phosphate/insulin growth factor‐II receptor (M6P/IGFII‐R) and C‐X‐C motif receptor 4 (CXC‐R4). The proline‐specific dipeptidyl peptidase also modulates the bioactivity of several chemokines. However, a number of enzymes displaying either DPP4‐like activities or representing structural homologues have been discovered in the past two decades and are referred to as DPP4 activity and/or structure homologue (DASH) proteins. Apart from DPP4, DASH proteins include fibroblast activation protein alpha (FAP), DPP8, DPP9, DPP4‐like protein 1 (DPL1, DPP6, DPPX L, DPPX S), DPP4‐like protein 2 (DPL2, DPP10) from the DPP4‐gene family S9b and structurally unrelated enzyme DPP2, displaying DPP4‐like activity. In contrast, DPP6 and DPP10 lack enzymatic DPP4‐like activity. These DASH proteins play important roles in the immune system involving quiescence (DPP2), proliferation (DPP8/DPP9), antigen‐presenting (DPP9), co‐stimulation (DPP4), T cell activation (DPP4), signal transduction (DPP4, DPP8 and DPP9), differentiation (DPP4, DPP8) and tissue remodelling (DPP4, FAP). Thus, they are involved in many pathophysiological processes and have therefore been proposed for potential biomarkers or even drug targets in various cancers (DPP4 and FAP) and inflammatory diseases (DPP4, DPP8/DPP9). However, they also pose the challenge of drug selectivity concerning other DASH members for better efficacy and/or avoidance of unwanted side effects. Therefore, this review unravels the complex roles of DASH proteins in immunology. PMID:26671446

The Comparative Effectiveness of Diabetes Prevention Strategies to Reduce Postpartum Weight Retention in Women With Gestational Diabetes Mellitus: The Gestational Diabetes’ Effects on Moms (GEM) Cluster Randomized Controlled Trial

PubMed Central

Hedderson, Monique M.; Brown, Susan D.; Albright, Cheryl L.; Ehrlich, Samantha F.; Tsai, Ai-Lin; Caan, Bette J.; Sternfeld, Barbara; Gordon, Nancy P.; Schmittdiel, Julie A.; Gunderson, Erica P.; Mevi, Ashley A.; Herman, William H.; Ching, Jenny; Crites, Yvonne; Quesenberry, Charles P.

2016-01-01

OBJECTIVE To compare the effectiveness of diabetes prevention strategies addressing postpartum weight retention for women with gestational diabetes mellitus (GDM) delivered at the health system level: mailed recommendations (usual care) versus usual care plus a Diabetes Prevention Program (DPP)–derived lifestyle intervention. RESEARCH DESIGN AND METHODS This study was a cluster randomized controlled trial of 44 medical facilities (including 2,280 women with GDM) randomized to intervention or usual care. The intervention included mailed gestational weight gain recommendations plus 13 telephone sessions between 6 weeks and 6 months postpartum. Primary outcomes included the following: proportion meeting the postpartum goals of 1) reaching pregravid weight if pregravid BMI <25.0 kg/m2 or 2) losing 5% of pregravid weight if BMI ≥25.0 kg/m2; and pregravid to postpartum weight change. RESULTS On average, over the 12-month postpartum period, women in the intervention had significantly higher odds of meeting weight goals than women in usual care (odds ratio [OR] 1.28 [95% CI 1.10, 1.47]). The proportion meeting weight goals was significantly higher in the intervention than usual care at 6 weeks (25.5 vs. 22.4%; OR 1.17 [1.01, 1.36]) and 6 months (30.6 vs. 23.9%; OR 1.45 [1.14, 1.83]). Condition differences were reduced at 12 months (33.0 vs. 28.0%; OR 1.25 [0.96, 1.62]). At 6 months, women in the intervention retained significantly less weight than women in usual care (mean 0.39 kg [SD 5.5] vs. 0.95 kg [5.5]; mean condition difference −0.64 kg [95% CI −1.13, −0.14]) and had greater increases in vigorous-intensity physical activity (mean condition difference 15.4 min/week [4.9, 25.8]). CONCLUSIONS A DPP-derived lifestyle intervention modestly reduced postpartum weight retention and increased vigorous-intensity physical activity. PMID:26657945

The Comparative Effectiveness of Diabetes Prevention Strategies to Reduce Postpartum Weight Retention in Women With Gestational Diabetes Mellitus: The Gestational Diabetes' Effects on Moms (GEM) Cluster Randomized Controlled Trial.

PubMed

Ferrara, Assiamira; Hedderson, Monique M; Brown, Susan D; Albright, Cheryl L; Ehrlich, Samantha F; Tsai, Ai-Lin; Caan, Bette J; Sternfeld, Barbara; Gordon, Nancy P; Schmittdiel, Julie A; Gunderson, Erica P; Mevi, Ashley A; Herman, William H; Ching, Jenny; Crites, Yvonne; Quesenberry, Charles P

2016-01-01

To compare the effectiveness of diabetes prevention strategies addressing postpartum weight retention for women with gestational diabetes mellitus (GDM) delivered at the health system level: mailed recommendations (usual care) versus usual care plus a Diabetes Prevention Program (DPP)-derived lifestyle intervention. This study was a cluster randomized controlled trial of 44 medical facilities (including 2,280 women with GDM) randomized to intervention or usual care. The intervention included mailed gestational weight gain recommendations plus 13 telephone sessions between 6 weeks and 6 months postpartum. Primary outcomes included the following: proportion meeting the postpartum goals of 1) reaching pregravid weight if pregravid BMI <25.0 kg/m(2) or 2) losing 5% of pregravid weight if BMI ≥25.0 kg/m(2); and pregravid to postpartum weight change. On average, over the 12-month postpartum period, women in the intervention had significantly higher odds of meeting weight goals than women in usual care (odds ratio [OR] 1.28 [95% CI 1.10, 1.47]). The proportion meeting weight goals was significantly higher in the intervention than usual care at 6 weeks (25.5 vs. 22.4%; OR 1.17 [1.01, 1.36]) and 6 months (30.6 vs. 23.9%; OR 1.45 [1.14, 1.83]). Condition differences were reduced at 12 months (33.0 vs. 28.0%; OR 1.25 [0.96, 1.62]). At 6 months, women in the intervention retained significantly less weight than women in usual care (mean 0.39 kg [SD 5.5] vs. 0.95 kg [5.5]; mean condition difference -0.64 kg [95% CI -1.13, -0.14]) and had greater increases in vigorous-intensity physical activity (mean condition difference 15.4 min/week [4.9, 25.8]). A DPP-derived lifestyle intervention modestly reduced postpartum weight retention and increased vigorous-intensity physical activity. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

The C allele of ATM rs11212617 does not associate with metformin response in the Diabetes Prevention Program.

PubMed

Florez, Jose C; Jablonski, Kathleen A; Taylor, Andrew; Mather, Kieren; Horton, Edward; White, Neil H; Barrett-Connor, Elizabeth; Knowler, William C; Shuldiner, Alan R; Pollin, Toni I

2012-09-01

The C allele at the rs11212617 polymorphism in the ataxia-telangiectasia-mutated (ATM) gene has been associated with greater clinical response to metformin in people with type 2 diabetes. We tested whether this variant modified the effect of metformin in the Diabetes Prevention Program (DPP), in which metformin reduced diabetes incidence by 31% in volunteers with impaired glucose tolerance. We genotyped rs11212617 in 2,994 DPP participants and analyzed its effects on diabetes incidence and related traits. Contrary to expectations, C carriers enjoyed no preventive advantage on metformin; their hazard ratio, compared with A carriers, was 1.17 ([95% CI 0.96-1.42], P = 0.13) under metformin. There were no significant differences by genotype in metformin's effects on insulin sensitivity, fasting glucose, glycated hemoglobin, or disposition index. The reported association of rs11212617 with metformin response was not confirmed for diabetes prevention or for effects on relevant physiologic parameters in the DPP.

Mothers After Gestational Diabetes in Australia Diabetes Prevention Program (MAGDA-DPP) post-natal intervention: an update to the study protocol for a randomized controlled trial.

PubMed

Shih, Sophy T F; Davis-Lameloise, Nathalie; Janus, Edward D; Wildey, Carol; Versace, Vincent L; Hagger, Virginia; Asproloupos, Dino; O'Reilly, Sharleen L; Phillips, Paddy A; Ackland, Michael; Skinner, Timothy; Oats, Jeremy; Carter, Rob; Best, James D; Dunbar, James A

2014-06-30

The Mothers After Gestational Diabetes in Australia Diabetes Prevention Program (MAGDA-DPP) is a randomized controlled trial (RCT) that aims to assess the effectiveness of a structured diabetes prevention intervention for women who had gestational diabetes. The original protocol was published in Trials (http://www.trialsjournal.com/content/14/1/339). This update reports on an additional exclusion criterion and change in first eligibility screening to provide greater clarity. The new exclusion criterion "surgical or medical intervention to treat obesity" has been added to the original protocol. The risks of developing diabetes will be affected by any medical or surgical intervention as its impact on obesity will alter the outcomes being assessed by MAGDA-DPP. The screening procedures have also been updated to reflect the current recruitment operation. The first eligibility screening is now taking place either during or after pregnancy, depending on recruitment strategy. Australian New Zealand Clinical Trials Registry ANZCTRN 12610000338066.

The rationale, design, and baseline characteristics of PREVENT-DM: A community-based comparative effectiveness trial of lifestyle intervention and metformin among Latinas with prediabetes.

PubMed

Perez, Alberly; Alos, Victor A; Scanlan, Adam; Maia, Catarina M; Davey, Adam; Whitaker, Robert C; Foster, Gary D; Ackermann, Ronald T; O'Brien, Matthew J

2015-11-01

Promotora Effectiveness Versus Metformin Trial (PREVENT-DM) is a randomized comparative effectiveness trial of a lifestyle intervention based on the Diabetes Prevention Program delivered by community health workers (or promotoras), metformin, and standard care. Eligibility criteria are Hispanic ethnicity, female sex, age ≥ 20 years, fluent Spanish-speaking status, BMI ≥ 23 kg/m(2), and prediabetes. We enrolled 92 participants and randomized them to one of the following three groups: standard care, DPP-based lifestyle intervention, or metformin. The primary outcome of the trial is the 12-month difference in weight between groups. Secondary outcomes include the following cardiometabolic markers: BMI, waist circumference, blood pressure, and fasting plasma glucose, hemoglobin A1C (HbA1c), total cholesterol, triglycerides, LDL cholesterol, HDL cholesterol, and insulin. PREVENT-DM participants are socioeconomically disadvantaged Latinas with a mean annual household income of $15,527 ± 9922 and educational attainment of 9.7 ± 3.6 years. Eighty-six percent of participants are foreign born, 20% have a prior history of gestational diabetes, and 71% have a first-degree relative with diagnosed diabetes. At baseline, PREVENT-DM participants had a mean age of 45.1 ± 12.5 years, weight of 178.8 ± 39.3 lbs, BMI of 33.3 ± 6.5 kg/m(2), HbA1c of 5.9 ± 0.2%, and waist circumference of 97.4 ± 11.1cm. Mean baseline levels of other cardiometabolic markers were normal. The PREVENT-DM study successfully recruited and randomized an understudied population of Latinas with prediabetes. This trial will be the first U.S. study to test the comparative effectiveness of metformin and lifestyle intervention versus standard care among prediabetic adults in a "real-world" setting. Copyright © 2015 Elsevier Inc. All rights reserved.

Incorporation of DPP6a and DPP6K variants in ternary Kv4 channel complex reconstitutes properties of A-type K current in rat cerebellar granule cells.

PubMed

Jerng, Henry H; Pfaffinger, Paul J

2012-01-01

Dipeptidyl peptidase-like protein 6 (DPP6) proteins co-assemble with Kv4 channel α-subunits and Kv channel-interacting proteins (KChIPs) to form channel protein complexes underlying neuronal somatodendritic A-type potassium current (I(SA)). DPP6 proteins are expressed as N-terminal variants (DPP6a, DPP6K, DPP6S, DPP6L) that result from alternative mRNA initiation and exhibit overlapping expression patterns. Here, we study the role DPP6 variants play in shaping the functional properties of I(SA) found in cerebellar granule (CG) cells using quantitative RT-PCR and voltage-clamp recordings of whole-cell currents from reconstituted channel complexes and native I(SA) channels. Differential expression of DPP6 variants was detected in rat CG cells, with DPP6K (41 ± 3%)>DPP6a (33 ± 3%)>DPP6S (18 ± 2%)>DPP6L (8 ± 3%). To better understand how DPP6 variants shape native neuronal I(SA), we focused on studying interactions between the two dominant variants, DPP6K and DPP6a. Although previous studies did not identify unique functional effects of DPP6K, we find that the unique N-terminus of DPP6K modulates the effects of KChIP proteins, slowing recovery and producing a negative shift in the steady-state inactivation curve. By contrast, DPP6a uses its distinct N-terminus to directly confer rapid N-type inactivation independently of KChIP3a. When DPP6a and DPP6K are co-expressed in ratios similar to those found in CG cells, their distinct effects compete in modulating channel function. The more rapid inactivation from DPP6a dominates during strong depolarization; however, DPP6K produces a negative shift in the steady-state inactivation curve and introduces a slow phase of recovery from inactivation. A direct comparison to the native CG cell I(SA) shows that these mixed effects are present in the native channels. Our results support the hypothesis that the precise expression and co-assembly of different auxiliary subunit variants are important factors in shaping the I(SA) functional properties in specific neuronal populations.

Exocarp Properties and Transcriptomic Analysis of Cucumber (Cucumis sativus) Fruit Expressing Age-Related Resistance to Phytophthora capsici

PubMed Central

Ando, Kaori; Carr, Kevin M.; Colle, Marivi; Mansfeld, Ben N.; Grumet, Rebecca

2015-01-01

Very young cucumber (Cucumis sativus) fruit are highly susceptible to infection by the oomycete pathogen, Phytophthora capsici. As the fruit complete exponential growth, at approximately 10–12 days post pollination (dpp), they transition to resistance. The development of age-related resistance (ARR) is increasingly recognized as an important defense against pathogens, however, underlying mechanisms are largely unknown. Peel sections from cucumber fruit harvested at 8 dpp (susceptible) and 16 dpp (resistant) showed equivalent responses to inoculation as did whole fruit, indicating that the fruit surface plays an important role in defense against P. capsici. Exocarp from 16 dpp fruit had thicker cuticles, and methanolic extracts of peel tissue inhibited growth of P. capsici in vitro, suggesting physical or chemical components to the ARR. Transcripts specifically expressed in the peel vs. pericarp showed functional differentiation. Transcripts predominantly expressed in the peel were consistent with fruit surface associated functions including photosynthesis, cuticle production, response to the environment, and defense. Peel-specific transcripts that exhibited increased expression in 16 dpp fruit relative to 8 dpp fruit, were highly enriched (P<0.0001) for response to stress, signal transduction, and extracellular and transport functions. Specific transcripts included genes associated with potential physical barriers (i.e., cuticle), chemical defenses (flavonoid biosynthesis), oxidative stress, penetration defense, and molecular pattern (MAMP)-triggered or effector-triggered (R-gene mediated) pathways. The developmentally regulated changes in gene expression between peels from susceptible- and resistant- age fruits suggest programming for increased defense as the organ reaches full size. PMID:26528543

Exocarp Properties and Transcriptomic Analysis of Cucumber (Cucumis sativus) Fruit Expressing Age-Related Resistance to Phytophthora capsici.

PubMed

Ando, Kaori; Carr, Kevin M; Colle, Marivi; Mansfeld, Ben N; Grumet, Rebecca

2015-01-01

Very young cucumber (Cucumis sativus) fruit are highly susceptible to infection by the oomycete pathogen, Phytophthora capsici. As the fruit complete exponential growth, at approximately 10-12 days post pollination (dpp), they transition to resistance. The development of age-related resistance (ARR) is increasingly recognized as an important defense against pathogens, however, underlying mechanisms are largely unknown. Peel sections from cucumber fruit harvested at 8 dpp (susceptible) and 16 dpp (resistant) showed equivalent responses to inoculation as did whole fruit, indicating that the fruit surface plays an important role in defense against P. capsici. Exocarp from 16 dpp fruit had thicker cuticles, and methanolic extracts of peel tissue inhibited growth of P. capsici in vitro, suggesting physical or chemical components to the ARR. Transcripts specifically expressed in the peel vs. pericarp showed functional differentiation. Transcripts predominantly expressed in the peel were consistent with fruit surface associated functions including photosynthesis, cuticle production, response to the environment, and defense. Peel-specific transcripts that exhibited increased expression in 16 dpp fruit relative to 8 dpp fruit, were highly enriched (P<0.0001) for response to stress, signal transduction, and extracellular and transport functions. Specific transcripts included genes associated with potential physical barriers (i.e., cuticle), chemical defenses (flavonoid biosynthesis), oxidative stress, penetration defense, and molecular pattern (MAMP)-triggered or effector-triggered (R-gene mediated) pathways. The developmentally regulated changes in gene expression between peels from susceptible- and resistant- age fruits suggest programming for increased defense as the organ reaches full size.

Androgens, Irregular Menses, and Risk of Diabetes and Coronary Artery Calcification in the Diabetes Prevention Program.

PubMed

Kim, Catherine; Aroda, Vanita R; Goldberg, Ronald B; Younes, Naji; Edelstein, Sharon L; Carrion-Petersen, MaryLou; Ehrmann, David A

2018-02-01

It is unclear whether relative elevations in androgens or irregular menses (IM) are associated with greater cardiometabolic risk among women who are already overweight and glucose intolerant. We conducted a secondary analysis of the Diabetes Prevention Program (DPP) and the Diabetes Prevention Program Outcomes Study (DPPOS). Participants included women with sex hormone measurements who did not use exogenous estrogen (n = 1422). We examined whether free androgen index (FAI) or IM was associated with diabetes risk during the DPP/DPPOS or with coronary artery calcification (CAC) at DPPOS year 10. Models were adjusted for menopausal status, age, race or ethnicity, randomization arm, body mass index (BMI), and hemoglobin A1c. Women had an average age of 48.2 ± 9.9 years. Elevations in FAI and IM were associated with greater BMI, waist circumference, and blood pressure and lower adiponectin. FAI was not associated with diabetes risk during the DPP/DPPOS [hazard ratio (HR) 0.97; 95% confidence interval (CI), 0.93 to 1.02] or increased odds of CAC [odds ratio (OR) 1.06; 95% CI, 0.92 to 1.23]. IM was also not associated with diabetes risk during the DPP/DPPOS (HR 1.07; 95% CI, 0.87 to 1.31) or increased odds of CAC (OR 0.89; 95% CI, 0.53 to 1.49). Women who had both relative elevations in FAI and IM had similar diabetes risk and odds of CAC as women without these conditions. Differences by treatment arm and menopausal status were not observed. Among midlife women who were already glucose intolerant and overweight, androgen concentrations and IM did not additionally contribute to increased risk for diabetes or CAC. Copyright © 2017 Endocrine Society

Effect of intensity and program delivery on the translation of DPP to worksites: A randomized controlled trial of Fuel Your Life

PubMed Central

DeJoy, David M.; Vandenberg, Robert J.; Corso, Phaedra; Padilla, Heather; Zuercher, Heather

2016-01-01

Objective To evaluate the effectiveness of the Fuel Your Life program, an adaptation of the Diabetes Prevention Program, utilizing implementation strategies commonly used in worksite programs – telephone coaching, small group coaching and self-study. Methods The primary outcomes of BMI and weight were examined in a randomized control trial conducted with city/county employees. Results Although the majority of participants in all three groups lost some weight, the phone group lost significantly more weight (4.9 lbs.), followed by the small groups (3.4 lbs.) and the self-study (2.7 lbs.). Of the total participants, 28.3% of the phone group, 20.6% of the small group and 15.7 of the self-study group lost 5% or more of their body weight. Conclusions Fuel Your Life (DPP) can be effectively disseminated using different implementation strategies that are tailored to the workplace. PMID:27820761

Identifying neuropeptide Y (NPY) as the main stress-related substrate of dipeptidyl peptidase 4 (DPP4) in blood circulation.

PubMed

Wagner, Leona; Kaestner, Florian; Wolf, Raik; Stiller, Harald; Heiser, Ulrich; Manhart, Susanne; Hoffmann, Torsten; Rahfeld, Jens-Ulrich; Demuth, Hans-Ulrich; Rothermundt, Matthias; von Hörsten, Stephan

2016-06-01

Dipeptidyl peptidase 4 (DPP4; EC 3.4.14.5; CD26) is a membrane-bound or shedded serine protease that hydrolyzes dipeptides from the N-terminus of peptides with either proline or alanine at the penultimate position. Substrates of DPP4 include several stress-related neuropeptides implicated in anxiety, depression and schizophrenia. A decline of DPP4-like activity has been reported in sera from depressed patient, but not fully characterized regarding DPP4-like enzymes, therapeutic interventions and protein. Sera from 16 melancholic- and 16 non-melancholic-depressed patients were evaluated for DPP4-like activities and the concentration of soluble DPP4 protein before and after treatment by anti-depressive therapies. Post-translational modification of DPP4-isoforms and degradation of NPY, Peptide YY (PYY), Galanin-like peptide (GALP), Orexin B (OrxB), OrxA, pituitary adenylate cyclase-activating polypeptide (PACAP) and substance P (SP) were studied in serum and in ex vivo human blood. N-terminal truncation of biotinylated NPY by endothelial membrane-bound DPP4 versus soluble DPP4 was determined in rat brain perfusates and spiked sera. Lower DPP4 activities in depressed patients were reversed by anti-depressive treatment. In sera, DPP4 contributed to more than 90% of the overall DPP4-like activity and correlated with its protein concentration. NPY displayed equal degradation in serum and blood, and was equally truncated by serum and endothelial DPP4. In addition, GALP and rat OrxB were identified as novel substrates of DPP4. NPY is the best DPP4-substrate in blood, being truncated by soluble and membrane DPP4, respectively. The decline of soluble DPP4 in acute depression could be reversed upon anti-depressive treatment. Peptidases from three functional compartments regulate the bioactivity of NPY in blood. Copyright © 2016 Elsevier Ltd. All rights reserved.

DIABETES PREVENTION PROGRAM

EPA Science Inventory

The Diabetes Prevention Program (DPP) was a major clinical trial, or research study, aimed at discovering whether either diet and exercise or the oral diabetes drug metformin (Glucophage) could prevent or delay the onset of type 2 diabetes in people with impaired glucose toleranc...

Nutritional Health Considerations for Persons with Spinal Cord Injury.

PubMed

Bigford, Gregory; Nash, Mark S

2017-01-01

Chronic spinal cord injury (SCI) often results in morbidity and mortality due to all-cause cardiovascular disease (CVD) and comorbid endocrine disorders. Several component risk factors for CVD, described as the cardiometabolic syndrome (CMS), are prevalent in SCI, with the individual risks of obesity and insulin resistance known to advance the disease prognosis to a greater extent than other established risks. Notably, adiposity and insulin resistance are attributed in large part to a commonly observed maladaptive dietary/nutritional profile. Although there are no evidence-based nutritional guidelines to address the CMS risk in SCI, contemporary treatment strategies advocate more comprehensive lifestyle management that includes sustained nutritional guidance as a necessary component for overall health management. This monograph describes factors in SCI that contribute to CMS risks, the current nutritional profile and its contribution to CMS risks, and effective treatment strategies including the adaptability of the Diabetes Prevention Program (DPP) to SCI. Establishing appropriate nutritional guidelines and recommendations will play an important role in addressing the CMS risks in SCI and preserving optimal long-term health.

The Role of Dipeptidyl Peptidase IV in Lung Metastasis of Breast Cancer Cells

DTIC Science & Technology

1999-05-01

Our studies focused on (1) cloning and sequencing of wild-type endothelial DPP IV (wtDPP IV) and preparation of truncated DPP IV ( tDPP IV); (2...that was identical to hepatic DPP IV. Acid extraction of rat lung yielded a tDPP IV, which was an effective inhibitor of breast cancer cell adhesion to

Synthesis, pharmacological evaluation and molecular docking studies of pyrimidinedione based DPP-4 inhibitors as antidiabetic agents

NASA Astrophysics Data System (ADS)

Jha, Vibhu; Bhadoriya, Kamlendra Singh

2018-04-01

Dipeptidyl peptidase-4 (DPP-4) inhibitors are a class of newly developed antidiabetic drugs that bock DPP-4. DPP-4 is responsible for degradation of incretins harmones such as GLP-1 (Glucagon like Peptide) and GIP (Gastric inhibitory polypeptide) that maintain blood-glucose level. Pyrimidinedione based compounds were designed and synthesized for DPP-4 inhibitory activity. These heterocycles were designed by taking Alogliptin as a reference DPP-4 inhibitors and synthesized as N-methylated and N-benzylated pyrimidinediones. These compounds were subjected to DPP-4 assay, five out of nine synthesized compounds have shown in vitro DPP-4 inhibitory activity in significant range. Further, molecular docking studies of these compounds were performed on DPP-4 subunit and compared with natural DPP-4 inhibitors like Flavone, Resveratrol, Quercetin, Diprotin A. Docking studies have led to the conclusion that there are some identical amino acid interactions as Tyr 666 and Tyr 662, seen in both synthesized compounds and natural DPP-4 inhibitors. This study completely gives a good scope for further derivatisation and optimization of synthesized compounds to get clinical candidate as DPP-4 inhibitor for antidiabetic activity.

Low DPP4 expression and activity in multiple sclerosis.

PubMed

Tejera-Alhambra, Marta; Casrouge, Armanda; de Andrés, Clara; Ramos-Medina, Rocío; Alonso, Bárbara; Vega, Janet; Albert, Matthew L; Sánchez-Ramón, Silvia

2014-02-01

Multiple sclerosis (MS) is a prototypic Th1/Th17 chronic autoimmune disease of the central nervous system. Dipeptidyl peptidase 4 (DPP4 or CD26) is a multifunctional molecule involved in autoimmune diseases' pathophysiology. We sought to integrate disparate pieces of data and analyze the plasma levels of sDPP4, DPP activity and DPP4 surface expression on T-cells in 129 MS patients with different clinical forms and 53 healthy controls, across two independent cohorts. Herein, we provide new evidence that sDPP4 concentration and DPP activity are significantly lower in MS patients than controls (p < 0.0001 and p < 0.01, respectively). In contrast, the frequency of circulating CD8(+)DPP4(hi) T-cells (p = 0.02) was increased in MS patients. This is the first study that simultaneously analyzes DPP4 expression and function in a large cohort of MS patients. Our data indicate a putative role for DPP4 in MS pathophysiology and suggest that a deeper understanding of surface versus shed DPP4 biology is warranted. Copyright © 2013 Elsevier Inc. All rights reserved.

Structures and mechanism of dipeptidyl peptidases 8 and 9, important players in cellular homeostasis and cancer.

PubMed

Ross, Breyan; Krapp, Stephan; Augustin, Martin; Kierfersauer, Reiner; Arciniega, Marcelino; Geiss-Friedlander, Ruth; Huber, Robert

2018-02-13

Dipeptidyl peptidases 8 and 9 are intracellular N-terminal dipeptidyl peptidases (preferentially postproline) associated with pathophysiological roles in immune response and cancer biology. While the DPP family member DPP4 is extensively characterized in molecular terms as a validated therapeutic target of type II diabetes, experimental 3D structures and ligand-/substrate-binding modes of DPP8 and DPP9 have not been reported. In this study we describe crystal and molecular structures of human DPP8 (2.5 Å) and DPP9 (3.0 Å) unliganded and complexed with a noncanonical substrate and a small molecule inhibitor, respectively. Similar to DPP4, DPP8 and DPP9 molecules consist of one β-propeller and α/β hydrolase domain, forming a functional homodimer. However, they differ extensively in the ligand binding site structure. In intriguing contrast to DPP4, where liganded and unliganded forms are closely similar, ligand binding to DPP8/9 induces an extensive rearrangement at the active site through a disorder-order transition of a 26-residue loop segment, which partially folds into an α-helix (R-helix), including R160/133, a key residue for substrate binding. As vestiges of this helix are also seen in one of the copies of the unliganded form, conformational selection may contributes to ligand binding. Molecular dynamics simulations support increased flexibility of the R-helix in the unliganded state. Consistently, enzyme kinetics assays reveal a cooperative allosteric mechanism. DPP8 and DPP9 are closely similar and display few opportunities for targeted ligand design. However, extensive differences from DPP4 provide multiple cues for specific inhibitor design and development of the DPP family members as therapeutic targets or antitargets.

Potency, selectivity and prolonged binding of saxagliptin to DPP4: maintenance of DPP4 inhibition by saxagliptin in vitro and ex vivo when compared to a rapidly-dissociating DPP4 inhibitor

PubMed Central

2012-01-01

Background Dipeptidylpeptidase 4 (DPP4) inhibitors have clinical benefit in patients with type 2 diabetes mellitus by increasing levels of glucose-lowering incretin hormones, such as glucagon-like peptide -1 (GLP-1), a peptide with a short half life that is secreted for approximately 1 hour following a meal. Since drugs with prolonged binding to their target have been shown to maximize pharmacodynamic effects while minimizing drug levels, we developed a time-dependent inhibitor that has a half-life for dissociation from DPP4 close to the duration of the first phase of GLP-1 release. Results Saxagliptin and its active metabolite (5-hydroxysaxagliptin) are potent inhibitors of human DPP4 with prolonged dissociation from its active site (Ki = 1.3 nM and 2.6 nM, t1/2 = 50 and 23 minutes respectively at 37°C). In comparison, both vildagliptin (3.5 minutes) and sitagliptin ( < 2 minutes) rapidly dissociated from DPP4 at 37°C. Saxagliptin and 5-hydroxysaxagliptin are selective for inhibition of DPP4 versus other DPP family members and a large panel of other proteases, and have similar potency and efficacy across multiple species. Inhibition of plasma DPP activity is used as a biomarker in animal models and clinical trials. However, most DPP4 inhibitors are competitive with substrate and rapidly dissociate from DPP4; therefore, the type of substrate, volume of addition and final concentration of substrate in these assays can change measured inhibition. We show that unlike a rapidly dissociating DPP4 inhibitor, inhibition of plasma DPP activity by saxagliptin and 5-hydroxysaxagliptin in an ex vivo assay was not dependent on substrate concentration when substrate was added rapidly because saxagliptin and 5-hydroxysaxagliptin dissociate slowly from DPP4, once bound. We also show that substrate concentration was important for rapidly dissociating DPP4 inhibitors. Conclusions Saxagliptin and its active metabolite are potent, selective inhibitors of DPP4, with prolonged dissociation from its active site. They also demonstrate prolonged inhibition of plasma DPP4 ex vivo in animal models, which implies that saxagliptin and 5-hydroxysaxagliptin would continue to inhibit DPP4 during rapid increases in substrates in vivo. PMID:22475049

DPP10 splice variants are localized in distinct neuronal populations and act to differentially regulate the inactivation properties of Kv4-based ion channels.

PubMed

Jerng, Henry H; Lauver, Aaron D; Pfaffinger, Paul J

2007-08-01

Dipeptidyl peptidase-like proteins (DPLs) and Kv-channel-interacting proteins (KChIPs) join Kv4 pore-forming subunits to form multi-protein complexes that underlie subthreshold A-type currents (I(SA)) in neuronal somatodendritic compartments. Here, we characterize the functional effects and brain distributions of N-terminal variants belonging to the DPL dipeptidyl peptidase 10 (DPP10). In the Kv4.2+KChIP3+DPP10 channel complex, all DPP10 variants accelerate channel gating kinetics; however, the splice variant DPP10a produces uniquely fast inactivation kinetics that accelerates with increasing depolarization. This DPP10a-specific inactivation dominates in co-expression studies with KChIP4a and other DPP10 isoforms. Real-time qRT-PCR and in situ hybridization analyses reveal differential expression of DPP10 variants in rat brain. DPP10a transcripts are prominently expressed in the cortex, whereas DPP10c and DPP10d mRNAs exhibit more diffuse distributions. Our results suggest that DPP10a underlies rapid inactivation of cortical I(SA), and the regulation of isoform expression may contribute to the variable inactivation properties of I(SA) across different brain regions.

Formation of the long range Dpp morphogen gradient.

PubMed

Schwank, Gerald; Dalessi, Sascha; Yang, Schu-Fee; Yagi, Ryohei; de Lachapelle, Aitana Morton; Affolter, Markus; Bergmann, Sven; Basler, Konrad

2011-07-01

The TGF-β homolog Decapentaplegic (Dpp) acts as a secreted morphogen in the Drosophila wing disc, and spreads through the target tissue in order to form a long range concentration gradient. Despite extensive studies, the mechanism by which the Dpp gradient is formed remains controversial. Two opposing mechanisms have been proposed: receptor-mediated transcytosis (RMT) and restricted extracellular diffusion (RED). In these scenarios the receptor for Dpp plays different roles. In the RMT model it is essential for endocytosis, re-secretion, and thus transport of Dpp, whereas in the RED model it merely modulates Dpp distribution by binding it at the cell surface for internalization and subsequent degradation. Here we analyzed the effect of receptor mutant clones on the Dpp profile in quantitative mathematical models representing transport by either RMT or RED. We then, using novel genetic tools, experimentally monitored the actual Dpp gradient in wing discs containing receptor gain-of-function and loss-of-function clones. Gain-of-function clones reveal that Dpp binds in vivo strongly to the type I receptor Thick veins, but not to the type II receptor Punt. Importantly, results with the loss-of-function clones then refute the RMT model for Dpp gradient formation, while supporting the RED model in which the majority of Dpp is not bound to Thick veins. Together our results show that receptor-mediated transcytosis cannot account for Dpp gradient formation, and support restricted extracellular diffusion as the main mechanism for Dpp dispersal. The properties of this mechanism, in which only a minority of Dpp is receptor-bound, may facilitate long-range distribution.

[Progress in the prevention of type 2 diabetes].

PubMed

Schernthaner, Guntram

2003-11-28

Type 2 diabetes mellitus is a major health problem associated with excess morbidity and mortality. Defects in the action and/or secretion of insulin are the two major abnormalities leading to development of glucose intolerance. Any intervention in the impaired glucose tolerance phase that reduces resistance to insulin or protects the beta-cells, or both, should prevent or delay progression to diabetes. The natural history of type 2 diabetes includes a preceding period of impaired glucose tolerance (IGT)/impaired fasting glucose (IFG) which provides an opportunity for targeted intervention within large communities. As the prevalence of this metabolic disorder is rapidly increasing and current treatment fails to stabilise the disease in most patients, prevention should be considered as a key objective in the near future. Lifestyle intervention studies have consistently shown that quite modest changes can reduce the progression from IGT to diabetes by 50-60%. The Diabetes Prevention Program (DPP) randomised trial has shown that a combined program of weight loss, improvement of diet and increase of physical exercise lowers the risk for development of type 2 diabetes by 58% compared with placebo. It may, however, not be possible to translate these successful findings to larger cohorts or maintain the lifestyle changes longer term. This has lead to consideration of pharmacotherapy. Benefits have been found for metformin, acarbose and troglitazone. Treatment with metformin was less effective than lifestyle modifications, resulting in an average reduction of risk for development of type 2 diabetes by 31% compared with placebo. Similarly, acarbose in the STOP-NIDDM trial reduced the risk of developing type 2 diabetes in patients with IGT by 25%. Remarkably, cardiovascular event rates, in particular myocardial infarction, were significantly reduced when acarbose was used instead of placebo in subjects with glucose intolerance. The ACE inhibitors captopril (CAPPP) or ramipril (HOPE) and the Angiotensin-II receptor antagonist losartan (LIFE) have been shown to reduce the appearance of diabetes by one third when given to patients with hypertension. Since many hypertensive patients are insulin-resistant and have an increased risk in developing type 2 diabetes, the protective effect of these classes of antihypertensive drugs might be explained by their antiinsulin-resistance effects.

An Introduction to the National DARE Parent Program. Program Brief.

ERIC Educational Resources Information Center

Illinois State Police, Springfield.

Drug Abuse Resistance Education (DARE) is a preventive drug education program intended to stop drug use before it begins. Its purpose is to help children say "no" to drug, alcohol, and tobacco use by teaching them techniques to resist peer pressure. The newest addition to the concept is the DARE Parent Program (DPP), created to stimulate…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Wenfei; Wang, Ying; Wang, Nianshuang

Middle East respiratory syndrome coronavirus (MERS-CoV) infects host cells through binding the receptor binding domain (RBD) on its spike glycoprotein to human receptor dipeptidyl peptidase 4 (hDPP4). Here, we report identification of critical residues on hDPP4 for RBD binding and virus entry through analysis of a panel of hDPP4 mutants. Based on the RBD–hDPP4 crystal structure we reported, the mutated residues were located at the interface between RBD and hDPP4, which potentially changed the polarity, hydrophobic or hydrophilic properties of hDPP4, thereby interfering or disrupting their interaction with RBD. Using surface plasmon resonance (SPR) binding analysis and pseudovirus infection assay,more » we showed that several residues in hDPP4–RBD binding interface were important on hDPP4–RBD binding and viral entry. These results provide atomic insights into the features of interactions between hDPP4 and MERS-CoV RBD, and also provide potential explanation for cellular and species tropism of MERS-CoV infection. - Highlights: • It has been demonstrated that MERS-CoV infects host cells through binding its envelope spike (S) glycoprotein to the host cellular receptor dipeptidyl peptidase 4 (DPP4). • To identify the critical residues on hDPP4 for RBD binding and virus entry, we constructed a panel of hDPP4 mutants based on structure-guided mutagenesis. • Using surface plasmon resonance (SPR) binding analysis and pseudovirus infection assay, we showed that several residues on hDPP4 had significant impacts on virus/receptor interactions and viral entry. • Our study has provided new insights into the features of interactions between hDPP4 and MERS-CoV RBD, and provides potential explanation for cellular and species tropism of MERS-CoV infection.« less

Boning up on DPP4, DPP4 substrates, and DPP4-adipokine interactions: Logical reasoning and known facts about bone related effects of DPP4 inhibitors.

PubMed

Glorie, Lorenzo; D'Haese, Patrick C; Verhulst, Anja

2016-11-01

Dipeptidyl peptidase 4 (DPP4) is a conserved exopeptidase with an important function in protein regulation. The activity of DPP4, an enzyme which can either be anchored to the plasma membrane or circulate free in the extracellular compartment, affects the glucose metabolism, cellular signaling, migration and differentiation, oxidative stress and the immune system. DPP4 is also expressed on the surface of osteoblasts, osteoclasts and osteocytes, and was found to play a role in collagen metabolism. Many substrates of DPP4 have an established role in bone metabolism, among which are incretins, gastrointestinal peptides and neuropeptides. In general, their effects favor bone formation, but some effects are complex and have not been completely elucidated. DPP4 and some of its substrates are known to interact with adipokines, playing an essential role in the energy metabolism. The prolongation of the half-life of incretins through DPP4 inhibition led to the development of these inhibitors to improve glucose tolerance in diabetes. Current literature indicates that the inhibition of DPP4 activity might also result in a beneficial effect on the bone metabolism, but the long-term effect of DPP4 inhibition on fracture outcome has not been entirely established. Diabetic as well as postmenopausal osteoporosis is associated with an increased activity of DPP4, as well as a shift in the expression levels of DPP4 substrates, their receptors, and adipokines. The interactions between these factors and their relationship in bone metabolism are therefore an interesting field of study. Copyright © 2016 Elsevier Inc. All rights reserved.

The persistent inhibitory properties of saxagliptin on renal dipeptidyl peptidase-4: Studies with HK-2 cells in vitro and normal rats in vivo.

PubMed

Uchii, Masako; Sakai, Mariko; Hotta, Yuhei; Saeki, Satoshi; Kimoto, Naoya; Hamaguchi, Akinori; Kitayama, Tetsuya; Kunori, Shunji

2017-11-01

Saxagliptin, a potent and selective DPP-4 inhibitor, exhibits a slow dissociation from DPP-4. We investigated the sustained effects of saxagliptin on renal DPP-4 activity in a washout study using renal tubular (HK-2) cells, and in a pharmacodynamic study using normal rats. In HK-2 cells, the inhibitory potency of saxagliptin on DPP-4 activity persisted after washout, while that of sitagliptin was clearly reduced. In normal rats, a single treatment of saxagliptin or sitagliptin inhibited the plasma DPP-4 activity to similar levels. The inhibitory action of saxagliptin on the renal DPP-4 activity was retained, even when its inhibitory effect on the plasma DPP-4 activity disappeared. However, the inhibitory action of sitagliptin on the renal DPP-4 activity was abolished in correlation with the inhibition of the plasma DPP-4 activity. In situ staining showed that saxagliptin suppressed the DPP-4 activity in both glomerular and tubular cells and its inhibitory effects were significantly higher than those of sitagliptin. Saxagliptin exerted a sustained inhibitory effect on the renal DPP-4 activity in vitro and in vivo. The long binding action of saxagliptin in renal tubular cells might involve the sustained inhibition of renal DPP-4. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

The Dipeptidyl Peptidases 4, 8, and 9 in Mouse Monocytes and Macrophages: DPP8/9 Inhibition Attenuates M1 Macrophage Activation in Mice.

PubMed

Waumans, Yannick; Vliegen, Gwendolyn; Maes, Lynn; Rombouts, Miche; Declerck, Ken; Van Der Veken, Pieter; Vanden Berghe, Wim; De Meyer, Guido R Y; Schrijvers, Dorien; De Meester, Ingrid

2016-02-01

Atherosclerosis remains the leading cause of death in Western countries. Dipeptidyl peptidase (DPP) 4 has emerged as a novel target for the prevention and treatment of atherosclerosis. Family members DPP8 and 9 are abundantly present in macrophage-rich regions of atherosclerotic plaques, and DPP9 inhibition attenuates activation of human M1 macrophages in vitro. Studying this family in a mouse model for atherosclerosis would greatly advance our knowledge regarding their potential as therapeutic targets. We found that DPP4 is downregulated during mouse monocyte-to-macrophage differentiation. DPP8 and 9 expression seems relatively low in mouse monocytes and macrophages. Viability of primary mouse macrophages is unaffected by DPP4 or DPP8/9 inhibition. Importantly, DPP8/9 inhibition attenuates macrophage activation as IL-6 secretion is significantly decreased. Mouse macrophages respond similarly to DPP inhibition, compared to human macrophages. This shows that the mouse could become a valid model species for the study of DPPs as therapeutic targets in atherosclerosis.

DPP4 in Diabetes

PubMed Central

Röhrborn, Diana; Wronkowitz, Nina; Eckel, Juergen

2015-01-01

Dipeptidyl-peptidase 4 (DPP4) is a glycoprotein of 110 kDa, which is ubiquitously expressed on the surface of a variety of cells. This exopeptidase selectively cleaves N-terminal dipeptides from a variety of substrates, including cytokines, growth factors, neuropeptides, and the incretin hormones. Expression of DPP4 is substantially dysregulated in a variety of disease states including inflammation, cancer, obesity, and diabetes. Since the incretin hormones, glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide (GIP), are major regulators of post-prandial insulin secretion, inhibition of DPP4 by the gliptin family of drugs has gained considerable interest for the therapy of type 2 diabetic patients. In this review, we summarize the current knowledge on the DPP4–incretin axis and evaluate most recent findings on DPP4 inhibitors. Furthermore, DPP4 as a type II transmembrane protein is also known to be cleaved from the cell membrane involving different metalloproteases in a cell-type-specific manner. Circulating, soluble DPP4 has been identified as a new adipokine, which exerts both para- and endocrine effects. Recently, a novel receptor for soluble DPP4 has been identified, and data are accumulating that the adipokine-related effects of DPP4 may play an important role in the pathogenesis of cardiovascular disease. Importantly, circulating DPP4 is augmented in obese and type 2 diabetic subjects, and it may represent a molecular link between obesity and vascular dysfunction. A critical evaluation of the impact of circulating DPP4 is presented, and the potential role of DPP4 inhibition at this level is also discussed. PMID:26284071

Structures of Human DPP7 Reveal the Molecular Basis of Specific Inhibition and the Architectural Diversity of Proline-Specific Peptidases

PubMed Central

Dong, Aiping; Seitova, Almagul; Crombett, Lissete; Shewchuk, Lisa M.; Hassell, Annie M.; Sweitzer, Sharon M.; Sweitzer, Thomas D.; McDevitt, Patrick J.; Johanson, Kyung O.; Kennedy-Wilson, Karen M.; Cossar, Doug; Bochkarev, Alexey; Gruber, Karl; Dhe-Paganon, Sirano

2012-01-01

Proline-specific dipeptidyl peptidases (DPPs) are emerging targets for drug development. DPP4 inhibitors are approved in many countries, and other dipeptidyl peptidases are often referred to as DPP4 activity- and/or structure-homologues (DASH). Members of the DASH family have overlapping substrate specificities, and, even though they share low sequence identity, therapeutic or clinical cross-reactivity is a concern. Here, we report the structure of human DPP7 and its complex with a selective inhibitor Dab-Pip (L-2,4-diaminobutyryl-piperidinamide) and compare it with that of DPP4. Both enzymes share a common catalytic domain (α/β-hydrolase). The catalytic pocket is located in the interior of DPP7, deep inside the cleft between the two domains. Substrates might access the active site via a narrow tunnel. The DPP7 catalytic triad is completely conserved and comprises Ser162, Asp418 and His443 (corresponding to Ser630, Asp708 and His740 in DPP4), while other residues lining the catalytic pockets differ considerably. The “specificity domains” are structurally also completely different exhibiting a β-propeller fold in DPP4 compared to a rare, completely helical fold in DPP7. Comparing the structures of DPP7 and DPP4 allows the design of specific inhibitors and thus the development of less cross-reactive drugs. Furthermore, the reported DPP7 structures shed some light onto the evolutionary relationship of prolyl-specific peptidases through the analysis of the architectural organization of their domains. PMID:22952628

Identification of Dipeptidyl-Peptidase (DPP)5 and DPP7 in Porphyromonas endodontalis, Distinct from Those in Porphyromonas gingivalis.

PubMed

Nishimata, Haruka; Ohara-Nemoto, Yuko; Baba, Tomomi T; Hoshino, Tomonori; Fujiwara, Taku; Shimoyama, Yu; Kimura, Shigenobu; Nemoto, Takayuki K

2014-01-01

Dipeptidyl peptidases (DPPs) that liberate dipeptides from the N-terminal end of oligopeptides are crucial for the growth of Porphyromonas species, anaerobic asaccharolytic gram negative rods that utilize amino acids as energy sources. Porphyromonas endodontalis is a causative agent of periapical lesions with acute symptoms and Asp/Glu-specific DPP11 has been solely characterized in this organism. In this study, we identified and characterized two P. endodontalis DPPs, DPP5 and DPP7. Cell-associated DPP activity toward Lys-Ala-4-methylcoumaryl-7-amide (MCA) was prominent in P. endodontalis ATCC 35406 as compared with the Porphyromonas gingivalis strains ATCC 33277, 16-1, HW24D1, ATCC 49417, W83, W50, and HNA99. The level of hydrolysis of Leu-Asp-MCA by DPP11, Gly-Pro-MCA by DPP4, and Met-Leu-MCA was also higher than in the P. gingivalis strains. MER236725 and MER278904 are P. endodontalis proteins belong to the S9- and S46-family peptidases, respectively. Recombinant MER236725 exhibited enzymatic properties including substrate specificity, and salt- and pH-dependence similar to P. gingivalis DPP5 belonging to the S9 family. However, the kcat/Km figure (194 µM-1·sec-1) for the most potent substrate (Lys-Ala-MCA) was 18.4-fold higher as compared to the P. gingivalis entity (10.5 µM-1·sec-1). In addition, P. endodontalis DPP5 mRNA and protein contents were increased several fold as compared with those in P. gingivalis. Recombinant MER278904 preferentially hydrolyzed Met-Leu-MCA and exhibited a substrate specificity similar to P. gingivalis DPP7 belonging to the S46 family. In accord with the deduced molecular mass of 818 amino acids, a 105-kDa band was immunologically detected, indicating that P. endodontalis DPP7 is an exceptionally large molecule in the DPP7/DPP11/S46 peptidase family. The enhancement of four DPP activities was conclusively demonstrated in P. endodontalis, and remarkable Lys-Ala-MCA-hydrolysis was achieved by qualitative and quantitative potentiation of the DPP5 molecule.

Identification of Dipeptidyl-Peptidase (DPP)5 and DPP7 in Porphyromonas endodontalis, Distinct from Those in Porphyromonas gingivalis

PubMed Central

Nishimata, Haruka; Ohara-Nemoto, Yuko; Baba, Tomomi T.; Hoshino, Tomonori; Fujiwara, Taku; Shimoyama, Yu; Kimura, Shigenobu; Nemoto, Takayuki K.

2014-01-01

Dipeptidyl peptidases (DPPs) that liberate dipeptides from the N-terminal end of oligopeptides are crucial for the growth of Porphyromonas species, anaerobic asaccharolytic gram negative rods that utilize amino acids as energy sources. Porphyromonas endodontalis is a causative agent of periapical lesions with acute symptoms and Asp/Glu-specific DPP11 has been solely characterized in this organism. In this study, we identified and characterized two P. endodontalis DPPs, DPP5 and DPP7. Cell-associated DPP activity toward Lys-Ala-4-methylcoumaryl-7-amide (MCA) was prominent in P. endodontalis ATCC 35406 as compared with the Porphyromonas gingivalis strains ATCC 33277, 16-1, HW24D1, ATCC 49417, W83, W50, and HNA99. The level of hydrolysis of Leu-Asp-MCA by DPP11, Gly-Pro-MCA by DPP4, and Met-Leu-MCA was also higher than in the P. gingivalis strains. MER236725 and MER278904 are P. endodontalis proteins belong to the S9- and S46-family peptidases, respectively. Recombinant MER236725 exhibited enzymatic properties including substrate specificity, and salt- and pH-dependence similar to P. gingivalis DPP5 belonging to the S9 family. However, the k cat/K m figure (194 µM−1·sec−1) for the most potent substrate (Lys-Ala-MCA) was 18.4-fold higher as compared to the P. gingivalis entity (10.5 µM−1·sec−1). In addition, P. endodontalis DPP5 mRNA and protein contents were increased several fold as compared with those in P. gingivalis. Recombinant MER278904 preferentially hydrolyzed Met-Leu-MCA and exhibited a substrate specificity similar to P. gingivalis DPP7 belonging to the S46 family. In accord with the deduced molecular mass of 818 amino acids, a 105-kDa band was immunologically detected, indicating that P. endodontalis DPP7 is an exceptionally large molecule in the DPP7/DPP11/S46 peptidase family. The enhancement of four DPP activities was conclusively demonstrated in P. endodontalis, and remarkable Lys-Ala-MCA-hydrolysis was achieved by qualitative and quantitative potentiation of the DPP5 molecule. PMID:25494328

A novel N-terminal motif of dipeptidyl peptidase-like proteins produces rapid inactivation of KV4.2 channels by a pore-blocking mechanism.

PubMed

Jerng, Henry H; Dougherty, Kevin; Covarrubias, Manuel; Pfaffinger, Paul J

2009-11-01

The somatodendritic subthreshold A-type K(+) current in neurons (I(SA)) depends on its kinetic and voltage-dependent properties to regulate membrane excitability, action potential repetitive firing, and signal integration. Key functional properties of the K(V)4 channel complex underlying I(SA) are determined by dipeptidyl peptidase-like proteins known as dipeptidyl peptidase 6 (DPP6) and dipeptidyl peptidase 10 (DPP10). Among the multiple known DPP10 isoforms with alternative N-terminal sequences, DPP10a confers exceptionally fast inactivation to K(V)4.2 channels. To elucidate the molecular basis of this fast inactivation, we investigated the structure-function relationship of the DPP10a N-terminal region and its interaction with the K(V)4.2 channel. Here, we show that DPP10a shares a conserved N-terminal sequence (MNQTA) with DPP6a (aka DPP6-E), which also induces fast inactivation. Deletion of the NQTA sequence in DPP10a eliminates this dramatic fast inactivation, and perfusion of MNQTA peptide to the cytoplasmic face of inside-out patches inhibits the K(V)4.2 current. DPP10a-induced fast inactivation exhibits competitive interactions with internally applied tetraethylammonium (TEA), and elevating the external K(+) concentration accelerates recovery from DPP10a-mediated fast inactivation. These results suggest that fast inactivation induced by DPP10a or DPP6a is mediated by a common N-terminal inactivation motif via a pore-blocking mechanism. This mechanism may offer an attractive target for novel pharmacological interventions directed at impairing I(SA) inactivation and reducing neuronal excitability.

Adipose Dipeptidyl Peptidase-4 and Obesity

PubMed Central

Sell, Henrike; Blüher, Matthias; Klöting, Nora; Schlich, Raphaela; Willems, Miriam; Ruppe, Florian; Knoefel, Wolfram Trudo; Dietrich, Arne; Fielding, Barbara A.; Arner, Peter; Frayn, Keith N.; Eckel, Jürgen

2013-01-01

OBJECTIVE To study expression of the recently identified adipokine dipeptidyl peptidase-4 (DPP4) in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) of patients with various BMIs and insulin sensitivities, as well as to assess circulating DPP4 in relation to obesity and insulin sensitivity. RESEARCH DESIGN AND METHODS DPP4 expression was measured in SAT and VAT from 196 subjects with a wide range of BMIs and insulin sensitivities. DPP4 release was measured ex vivo in paired biopsies from SAT and VAT as well as in vivo from SAT of lean and obese patients. Circulating DPP4 was measured in insulin-sensitive and insulin-resistant BMI-matched obese patients. RESULTS DPP4 expression was positively correlated with BMI in both SAT and VAT, with VAT consistently displaying higher expression than SAT. Ex vivo release of DPP4 from adipose tissue explants was higher in VAT than in SAT in both lean and obese patients, with obese patients displaying higher DPP4 release than lean controls. Net release of DPP4 from adipose tissue was also demonstrated in vivo with greater release in obese subjects than in lean subjects and in women than in men. Insulin-sensitive obese patients had significantly lower circulating DPP4 than did obesity-matched insulin-resistant patients. In this experiment, DPP4 positively correlated with the amount of VAT, adipocyte size, and adipose tissue inflammation. CONCLUSIONS DPP4, a novel adipokine, has a higher release from VAT that is particularly pronounced in obese and insulin-resistant patients. Our data suggest that DPP4 may be a marker for visceral obesity, insulin resistance, and the metabolic syndrome. PMID:24130353

Mechanism-based population pharmacokinetic modelling in diabetes: vildagliptin as a tight binding inhibitor and substrate of dipeptidyl peptidase IV

PubMed Central

Landersdorfer, Cornelia B; He, Yan-Ling; Jusko, William J

2012-01-01

AIMS To assess the pharmacokinetics of vildagliptin at different doses and build a mechanism-based population model that simultaneously describes vildagliptin pharmacokinetics and its effects on DPP-4 activity based on underlying physiology and biology. METHODS Vildagliptin concentrations and DPP-4 activity vs. time from 13 type 2 diabetic patients after oral vildagliptin 10, 25 or 100 mg and placebo twice daily for 28 days were co-modelled. NONMEM VI and S-ADAPT were utilized for population modelling. RESULTS A target-mediated drug disposition (TMDD) model accounting for capacity-limited high affinity binding of vildagliptin to DPP-4 in plasma and tissues had good predictive performance. Modelling the full time course of the vildagliptin-DPP-4 interaction suggested parallel vildagliptin dissociation from DPP-4 by a slow first-order process and hydrolysis by DPP-4 to an inactive metabolite as a disposition mechanism. Due to limited amounts of DPP-4, vildagliptin concentrations increased slightly more than dose proportionally. This newly proposed model and the parameter estimates are supported by published in vitro studies. Mean parameter estimates (inter-individual coefficient of variation) were: non-saturable clearance 36 l h−1 (25%), central volume of distribution 22 l (37%), half-life of dissociation from DPP-4 1.1 h (94%) and half-life of hydrolysis 6.3 h (81%). CONCLUSIONS Vildagliptin is both an inhibitor and substrate for DPP-4. By utilizing the TMDD approach, slow dissociation of vildagliptin from DPP-4 was found in patients and the half-life of hydrolysis by DPP-4 estimated. This model can be used to predict DPP-4 inhibition effects of other dosage regimens and be modified for other DPP-4 inhibitors to differentiate their properties. PMID:22442826

Dipeptidyl peptidase 4 - An important digestive peptidase in Tenebrio molitor larvae.

PubMed

Tereshchenkova, Valeriia F; Goptar, Irina A; Kulemzina, Irina A; Zhuzhikov, Dmitry P; Serebryakova, Marina V; Belozersky, Mikhail A; Dunaevsky, Yakov E; Oppert, Brenda; Filippova, Irina Yu; Elpidina, Elena N

2016-09-01

Dipeptidyl peptidase 4 (DPP 4) is a proline specific serine peptidase that plays an important role in different regulatory processes in mammals. In this report, we isolated and characterized a unique secreted digestive DPP 4 from the anterior midgut of a stored product pest, Tenebrio molitor larvae (TmDPP 4), with a biological function different than that of the well-studied mammalian DPP 4. The sequence of the purified enzyme was confirmed by mass-spectrometry, and was identical to the translated RNA sequence found in a gut EST database. The purified peptidase was characterized according to its localization in the midgut, and substrate specificity and inhibitor sensitivity were compared with those of human recombinant DPP 4 (rhDPP 4). The T. molitor enzyme was localized mainly in the anterior midgut of the larvae, and 81% of the activity was found in the fraction of soluble gut contents, while human DPP 4 is a membrane enzyme. TmDPP 4 was stable in the pH range 5.0-9.0, with an optimum activity at pH 7.9, similar to human DPP 4. Only specific inhibitors of serine peptidases, diisopropyl fluorophosphate and phenylmethylsulfonyl fluoride, suppressed TmDPP 4 activity, and the specific dipeptidyl peptidase inhibitor vildagliptin was most potent. The highest rate of TmDPP 4 hydrolysis was found for the synthetic substrate Arg-Pro-pNA, while Ala-Pro-pNA was a better substrate for rhDPP 4. Related to its function in the insect midgut, TmDPP 4 efficiently hydrolyzed the wheat storage proteins gliadins, which are major dietary proteins of T. molitor. Published by Elsevier Ltd.

Identification and Characterization of Prokaryotic Dipeptidyl-peptidase 5 from Porphyromonas gingivalis *

PubMed Central

Ohara-Nemoto, Yuko; Rouf, Shakh M. A.; Naito, Mariko; Yanase, Amie; Tetsuo, Fumi; Ono, Toshio; Kobayakawa, Takeshi; Shimoyama, Yu; Kimura, Shigenobu; Nakayama, Koji; Saiki, Keitarou; Konishi, Kiyoshi; Nemoto, Takayuki K.

2014-01-01

Porphyromonas gingivalis, a Gram-negative asaccharolytic anaerobe, is a major causative organism of chronic periodontitis. Because the bacterium utilizes amino acids as energy and carbon sources and incorporates them mainly as dipeptides, a wide variety of dipeptide production processes mediated by dipeptidyl-peptidases (DPPs) should be beneficial for the organism. In the present study, we identified the fourth P. gingivalis enzyme, DPP5. In a dpp4-7-11-disrupted P. gingivalis ATCC 33277, a DPP7-like activity still remained. PGN_0756 possessed an activity indistinguishable from that of the mutant, and was identified as a bacterial orthologue of fungal DPP5, because of its substrate specificity and 28.5% amino acid sequence identity with an Aspergillus fumigatus entity. P. gingivalis DPP5 was composed of 684 amino acids with a molecular mass of 77,453, and existed as a dimer while migrating at 66 kDa on SDS-PAGE. It preferred Ala and hydrophobic residues, had no activity toward Pro at the P1 position, and no preference for hydrophobic P2 residues, showed an optimal pH of 6.7 in the presence of NaCl, demonstrated Km and kcat/Km values for Lys-Ala-MCA of 688 μm and 11.02 μm−1 s−1, respectively, and was localized in the periplasm. DPP5 elaborately complemented DPP7 in liberation of dipeptides with hydrophobic P1 residues. Examinations of DPP- and gingipain gene-disrupted mutants indicated that DPP4, DPP5, DPP7, and DPP11 together with Arg- and Lys-gingipains cooperatively liberate most dipeptides from nutrient oligopeptides. This is the first study to report that DPP5 is expressed not only in eukaryotes, but also widely distributed in bacteria and archaea. PMID:24398682

Dipeptidyl peptidase-4 inhibitors and risk of heart failure in type 2 diabetes: systematic review and meta-analysis of randomised and observational studies.

PubMed

Li, Ling; Li, Sheyu; Deng, Ke; Liu, Jiali; Vandvik, Per Olav; Zhao, Pujing; Zhang, Longhao; Shen, Jiantong; Bala, Malgorzata M; Sohani, Zahra N; Wong, Evelyn; Busse, Jason W; Ebrahim, Shanil; Malaga, German; Rios, Lorena P; Wang, Yingqiang; Chen, Qunfei; Guyatt, Gordon H; Sun, Xin

2016-02-17

To examine the association between dipeptidyl peptidase-4 (DPP-4) inhibitors and the risk of heart failure or hospital admission for heart failure in patients with type 2 diabetes. Systematic review and meta-analysis of randomised and observational studies. Medline, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov searched up to 25 June 2015, and communication with experts. Randomised controlled trials, non-randomised controlled trials, cohort studies, and case-control studies that compared DPP-4 inhibitors against placebo, lifestyle modification, or active antidiabetic drugs in adults with type 2 diabetes, and explicitly reported the outcome of heart failure or hospital admission for heart failure. Teams of paired reviewers independently screened for eligible studies, assessed risk of bias, and extracted data using standardised, pilot tested forms. Data from trials and observational studies were pooled separately; quality of evidence was assessed by the GRADE approach. Eligible studies included 43 trials (n=68,775) and 12 observational studies (nine cohort studies, three nested case-control studies; n=1,777,358). Pooling of 38 trials reporting heart failure provided low quality evidence for a possible similar risk of heart failure between DPP-4 inhibitor use versus control (42/15,701 v 33/12,591; odds ratio 0.97 (95% confidence interval 0.61 to 1.56); risk difference 2 fewer (19 fewer to 28 more) events per 1000 patients with type 2 diabetes over five years). The observational studies provided effect estimates generally consistent with trial findings, but with very low quality evidence. Pooling of the five trials reporting admission for heart failure provided moderate quality evidence for an increased risk in patients treated with DPP-4 inhibitors versus control (622/18,554 v 552/18,474; 1.13 (1.00 to 1.26); 8 more (0 more to 16 more)). The pooling of adjusted estimates from observational studies similarly suggested (with very low quality evidence) a possible increased risk of admission for heart failure (adjusted odds ratio 1.41, 95% confidence interval 0.95 to 2.09) in patients treated with DPP-4 inhibitors (exclusively sitagliptin) versus no use. The relative effect of DPP-4 inhibitors on the risk of heart failure in patients with type 2 diabetes is uncertain, given the relatively short follow-up and low quality of evidence. Both randomised controlled trials and observational studies, however, suggest that these drugs may increase the risk of hospital admission for heart failure in those patients with existing cardiovascular diseases or multiple risk factors for vascular diseases, compared with no use. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Inhibition of dipeptidyl peptidase IV prevents high fat diet-induced liver cancer angiogenesis by downregulating chemokine ligand 2.

PubMed

Qin, Chen-Jie; Zhao, Ling-Hao; Zhou, Xu; Zhang, Hui-Lu; Wen, Wen; Tang, Liang; Zeng, Min; Wang, Ming-Da; Fu, Gong-Bo; Huang, Shuai; Huang, Wei-Jian; Yang, Yuan; Bao, Zhi-Jun; Zhou, Wei-Ping; Wang, Hong-Yang; Yan, He-Xin

2018-04-28

Obesity is a major risk factor for hepatocellular carcinoma (HCC) and is typically accompanied by higher levels of serum dipeptidyl peptidase 4 (DPP4). However, the role of DPP4 in obesity-promoted HCC is unclear. Here, we found that consumption of a high-fat diet (HFD) promoted HCC cell proliferation and metastasis and led to poor survival in a carcinogen-induced model of HCC in rats. Notably, genetic ablation of DPP4 or treatment with a DPP4 inhibitor (vildagliptin) prevented HFD-induced HCC. Moreover, HFD-induced DPP4 activity facilitated angiogenesis and cancer cell metastasis in vitro and in vivo, and vildagliptin prevented tumor progression by mediating the pro-angiogenic role of chemokine ligand 2 (CCL2). Loss of DPP4 effectively reversed HFD-induced CCL2 production and angiogenesis, indicating that the DPP4/CCL2/angiogenesis cascade had key roles in HFD-associated HCC progression. Furthermore, concomitant changes in serum DPP4 and CCL2 were observed in 210 patients with HCC, and high serum DPP4 activity was associated with poor clinical prognosis. These results revealed a link between obesity-related high serum DPP4 activity and HCC progression. Inhibition of DPP4 may represent a novel therapeutic intervention for patients with HCC. Copyright © 2018 Elsevier B.V. All rights reserved.

Predicting DPP-IV inhibitors with machine learning approaches

NASA Astrophysics Data System (ADS)

Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun

2017-04-01

Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

Boundary Dpp promotes growth of medial and lateral regions of the Drosophila wing.

PubMed

Barrio, Lara; Milán, Marco

2017-07-04

The gradient of Decapentaplegic (Dpp) in the Drosophila wing has served as a paradigm to characterize the role of morphogens in regulating patterning. However, the role of this gradient in regulating tissue size is a topic of intense debate as proliferative growth is homogenous. Here, we combined the Gal4/UAS system and a temperature-sensitive Gal80 molecule to induce RNAi-mediated depletion of dpp and characterise the spatial and temporal requirement of Dpp in promoting growth. We show that Dpp emanating from the AP compartment boundary is required throughout development to promote growth by regulating cell proliferation and tissue size. Dpp regulates growth and proliferation rates equally in central and lateral regions of the developing wing appendage and reduced levels of Dpp affects similarly the width and length of the resulting wing. We also present evidence supporting the proposal that graded activity of Dpp is not an absolute requirement for wing growth.

The effect of DPP-4 inhibitors on asthma control: an administrative database study to evaluate a potential pathophysiological relationship.

PubMed

Colice, Gene; Price, David; Gerhardsson de Verdier, Maria; Rabon-Stith, Karma; Ambrose, Christopher; Cappell, Katherine; Irwin, Debra E; Juneau, Paul; Vlahiotis, Anna

2017-01-01

DPP-4 may regulate immunological pathways implicated in asthma. Assessing whether DPP-4 inhibitor (DPP-4i) use might affect asthma control is clinically important because DPP-4i use in type 2 diabetes mellitus management (T2DM) is increasing. This study evaluated associations between DPP-4i use and asthma control. This was a retrospective, observational, matched cohort study using administrative claims in the MarketScan ® Commercial Claims and Encounters (Commercial) and Medicare Supplemental and Coordination of Benefits (Medicare Supplemental) databases. Adult asthma patients initiating an oral DPP-4i or a non-DPP-4i between November 1, 2006 and March 31, 2014 were included. Patients were followed for asthma-related outcomes for 12 months after initiation of the antidiabetes medication. Outcomes included risk-domain asthma control (RDAC), defined as no asthma hospitalizations, no lower respiratory tract infections, and no oral corticosteroid (OCS) prescriptions; overall asthma control (RDAC criteria plus limited short-acting beta agonist use); treatment stability (RDAC criteria plus no increase of ≥50% in inhaled corticosteroid dose or addition of other asthma therapy); and severe asthma exacerbation rates (asthma-related hospitalizations, emergency room visits, or acute treatments with OCS). Comparisons were made between two matched cohorts (DPP-4i vs. non-DPP-4i initiators) using multivariable logistic regression and generalized linear modeling. Covariates included baseline demographic and clinical characteristics related to asthma and T2DM. The adjusted odds of achieving RDAC (odds ratio [OR]: 1.05; 95% CI: 0.964 to 1.147), overall asthma control (OR: 1.04; 95% CI: 0.956 to 1.135), and treatment stability (OR: 1.04; 95% CI: 0.949 to 1.115) did not differ between the DPP-4i and non-DPP-4i cohorts. A difference was not found between cohorts in severe asthma exacerbation rates during the 12 months following initiation of antidiabetes treatment (mean = 0.32 vs. 0.34 exacerbations per subject-year, respectively; p =0.064). Asthma control was similar between patients initiating DPP-4i and non-DPP-4i antidiabetes medications, suggesting no association between DPP-4i use and asthma control.

Three extracellular dipeptidyl peptidases found in Aspergillus oryzae show varying substrate specificities.

PubMed

Maeda, Hiroshi; Sakai, Daisuke; Kobayashi, Takuji; Morita, Hiroto; Okamoto, Ayako; Takeuchi, Michio; Kusumoto, Ken-Ichi; Amano, Hitoshi; Ishida, Hiroki; Yamagata, Youhei

2016-06-01

Three extracellular dipeptidyl peptidase genes, dppB, dppE, and dppF, were unveiled by sequence analysis of the Aspergillus oryzae genome. We investigated their differential enzymatic profiles, in order to gain an understanding of the diversity of these genes. The three dipeptidyl peptidases were expressed using Aspergillus nidulans as the host. Each recombinant enzyme was purified and subsequently characterized. The enzymes displayed similar optimum pH values, but optimum temperatures, pH stabilities, and substrate specificities varied. DppB was identified as a Xaa-Prolyl dipeptidyl peptidase, while DppE scissile substrates were similar to the substrates for Aspergillus fumigatus DPPV (AfDPPV). DppF was found to be a novel enzyme that could digest both substrates for A. fumigatus DPPIV and AfDPPV. Semi-quantitative PCR revealed that the transcription of dppB in A. oryzae was induced by protein substrates and repressed by the addition of an inorganic nitrogen source, despite the presence of protein substrates. The transcription of dppE depended on its growth time, while the transcription of dppF was not affected by the type of the nitrogen source in the medium, and it started during the early stage of the fungal growth. Based on these results, we conclude that these enzymes may represent the nutrition acquisition enzymes. Additionally, DppF may be one of the sensor peptidases responsible for the detection of the protein substrates in A. oryzae environment. DppB may be involved in nitrogen assimilation control, since the transcription of dppB was repressed by NaNO3, despite the presence of protein substrates.

Substrate Binding Protein DppA1 of ABC Transporter DppBCDF Increases Biofilm Formation in Pseudomonas aeruginosa by Inhibiting Pf5 Prophage Lysis

PubMed Central

Lee, Yunho; Song, Sooyeon; Sheng, Lili; Zhu, Lei; Kim, Jun-Seob; Wood, Thomas K.

2018-01-01

Filamentous phage impact biofilm development, stress tolerance, virulence, biofilm dispersal, and colony variants. Previously, we identified 137 Pseudomonas aeruginosa PA14 mutants with more than threefold enhanced and 88 mutants with more than 10-fold reduced biofilm formation by screening 5850 transposon mutants (PLoS Pathogens 5: e1000483, 2009). Here, we characterized the function of one of these 225 mutations, dppA1 (PA14_58350), in regard to biofilm formation. DppA1 is a substrate-binding protein (SBP) involved in peptide utilization via the DppBCDF ABC transporter system. We show that compared to the wild-type strain, inactivating dppA1 led to 68-fold less biofilm formation in a static model and abolished biofilm formation in flow cells. Moreover, the dppA1 mutant had a delay in swarming and produced 20-fold less small-colony variants, and both biofilm formation and swarming were complemented by producing DppA1. A whole-transcriptome analysis showed that only 10 bacteriophage Pf5 genes were significantly induced in the biofilm cells of the dppA1 mutant compared to the wild-type strain, and inactivation of dppA1 resulted in a 600-fold increase in Pf5 excision and a million-fold increase in phage production. As expected, inactivating Pf5 genes PA0720 and PA0723 increased biofilm formation substantially. Inactivation of DppA1 also reduced growth (due to cell lysis). Hence, DppA1 increases biofilm formation by repressing Pf5 prophage. PMID:29416528

Substituted 4-carboxymethylpyroglutamic acid diamides as potent and selective inhibitors of fibroblast activation protein.

PubMed

Tsai, Ting-Yueh; Yeh, Teng-Kuang; Chen, Xin; Hsu, Tsu; Jao, Yu-Chen; Huang, Chih-Hsiang; Song, Jen-Shin; Huang, Yu-Chen; Chien, Chia-Hui; Chiu, Jing-Huai; Yen, Shih-Chieh; Tang, Hung-Kuan; Chao, Yu-Sheng; Jiaang, Weir-Torn

2010-09-23

Fibroblast activation protein (FAP) belongs to the prolyl peptidase family. FAP inhibition is expected to become a new antitumor target. Most known FAP inhibitors often resemble the dipeptide cleavage products, with a boroproline at the P1 site; however, these inhibitors also inhibit DPP-IV, DPP-II, DPP8, and DPP9. Potent and selective FAP inhibitor is needed in evaluating that FAP as a therapeutic target. Therefore, it is important to develop selective FAP inhibitors for the use of target validation. To achieve this, optimization of the nonselective DPP-IV inhibitor 8 led to the discovery of a new class of substituted 4-carboxymethylpyroglutamic acid diamides as FAP inhibitors. SAR studies resulted in a number of FAP inhibitors having IC(50) of <100 nM with excellent selectivity over DPP-IV, DPP-II, DPP8, and DPP9 (IC(50) > 100 μM). Compounds 18a, 18b, and 19 are the only known potent and selective FAP inhibitors, which prompts us to further study the physiological role of FAP.

Dipeptidyl peptidase-4: A key player in chronic liver disease

PubMed Central

Itou, Minoru; Kawaguchi, Takumi; Taniguchi, Eitaro; Sata, Michio

2013-01-01

Dipeptidyl peptidase-4 (DPP-4) is a membrane-associated peptidase, also known as CD26. DPP-4 has widespread organ distribution throughout the body and exerts pleiotropic effects via its peptidase activity. A representative target peptide is glucagon-like peptide-1, and inactivation of glucagon-like peptide-1 results in the development of glucose intolerance/diabetes mellitus and hepatic steatosis. In addition to its peptidase activity, DPP-4 is known to be associated with immune stimulation, binding to and degradation of extracellular matrix, resistance to anti-cancer agents, and lipid accumulation. The liver expresses DPP-4 to a high degree, and recent accumulating data suggest that DPP-4 is involved in the development of various chronic liver diseases such as hepatitis C virus infection, non-alcoholic fatty liver disease, and hepatocellular carcinoma. Furthermore, DPP-4 occurs in hepatic stem cells and plays a crucial role in hepatic regeneration. In this review, we described the tissue distribution and various biological effects of DPP-4. Then, we discussed the impact of DPP-4 in chronic liver disease and the possible therapeutic effects of a DPP-4 inhibitor. PMID:23613622

Application of a modified diabetes prevention program with adolescents.

PubMed

Geria, Kimberly; Beitz, Janice M

2017-12-29

The purpose of this study was to increase type 2 diabetes (T2DM) awareness and decrease T2DM risk factors by examining effectiveness of a modified version of the Centers for Disease Control and Prevention (CDC) Diabetes Prevention Program (DPP) with adolescents. A quasi-experimental one-group, pretest/posttest design was used to determine impact of the modified DPP on adolescents. Study intervention was incorporated into the health education curriculum at a public charter school and implemented over 11 weeks. Study sample included primarily African-American and Hispanic adolescents (N = 101) aged 13-18 attending the public charter school in a New Jersey urban community. Instrumentation included valid, reliable measures of self-efficacy for healthy eating, physical activity, food knowledge, and healthy food choices. Participants' pretest/posttest waist circumference and body mass index (BMI) were collected. Outcomes revealed significant (p < .001) increase in participants' food knowledge, self-efficacy for choosing healthy foods and performing physical activity, healthy food choices, and amount of weekly aerobic exercise. Reductions in BMI and waist circumference were statistically significant (p < .05). A modified DPP adapted for adolescents' learning needs lowered risk for T2DM. Implications for clinical practice, education, and research are posed. © 2017 Wiley Periodicals, Inc.

Identification and characterization of a dipeptidyl peptidase IV inhibitor from aronia juice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kozuka, Miyuki; Yamane, Takuya, E-mail: t-yamane@pharm.hokudai.ac.jp; Nakano, Yoshihisa

Aronia berries have many potential effects on health, including an antioxidant effect, effect for antimutagenesis, hepatoprotection and cardioprotection, an antidiabetic effect and inhibition of cancer cell proliferation. Previous human studies have shown that aronia juice may be useful for treatment of obesity disorders. In this study, we found that aronia juice has an inhibitory effect against dipeptidyl peptidase IV (DPP IV) (EC 3.4.14.5). DPP IV is a peptidase that cleaves the N-terminal region of incretins such as glucagon-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). Inactivation of incretins by DPP IV induces reduction of insulin secretion. Furthermore, we identified thatmore » cyanidin 3, 5-diglucoside as the DPP IV inhibitor in aronia juice. DPP IV was inhibited more strongly by cyanidin 3, 5-diglucoside than by cyanidin and cyanidin 3-glucoside. The results suggest that DPP IV is inhibited by cyanidin 3, 5-diglucoside present in aronia juice. The antidiabetic effect of aronia juice may be mediated through DPP IV inhibition by cyanidin 3, 5-diglucoside. - Highlights: • DPP IV activity is inhibited by aronia juice. • DPP IV inhibitor is cyanidin 3, 5-diglucoside in aronia juice. • DPP IV is inhibited by cyanidin 3, 5-diglucoside more than cyanidin and cyanidin 3-glucoside.« less

Chronic administration of DSP-7238, a novel, potent, specific and substrate-selective DPP IV inhibitor, improves glycaemic control and beta-cell damage in diabetic mice.

PubMed

Furuta, Y; Horiguchi, M; Sugaru, E; Ono-Kishino, M; Otani, M; Sakai, M; Masui, Y; Tsuchida, A; Sato, Y; Takubo, K; Hochigai, H; Kimura, H; Nakahira, H; Nakagawa, T; Taiji, M

2010-05-01

The purpose of this study is to assess the in vitro enzyme inhibition profile of DSP-7238, a novel non-cyanopyrrolidine dipeptidyl peptidase (DPP) IV inhibitor and to evaluate the acute and chronic effects of this compound on glucose metabolism in two different mouse models of type 2 diabetes. The in vitro enzyme inhibition profile of DSP-7238 was assessed using plasma and recombinant enzymes including DPP IV, DPP II, DPP8, DPP9 and fibroblast activation protein alpha (FAPalpha) with fluorogenic substrates. The inhibition type was evaluated based on the Lineweaver-Burk plot. Substrate selectivity of DSP-7238 and comparator DPP IV inhibitors (vildagliptin, sitagliptin, saxagliptin and linagliptin) was evaluated by mass spectrometry based on the changes in molecular weight of peptide substrates caused by release of N-terminal dipeptides. In the in vivo experiments, high-fat diet-induced obese (DIO) mice were subjected to oral glucose tolerance test (OGTT) following a single oral administration of DSP-7238. To assess the chronic effects of DSP-7238 on glycaemic control and pancreatic beta-cell damage, DSP-7238 was administered for 11 weeks to mice made diabetic by a combination of high-fat diet (HFD) and a low-dose of streptozotocin (STZ). After the dosing period, HbA1c was measured and pancreatic damage was evaluated by biological and histological analyses. DSP-7238 and sitagliptin both competitively inhibited recombinant human DPP IV (rhDPP IV) with K(i) values of 0.60 and 2.1 nM respectively. Neither vildagliptin nor saxagliptin exhibited competitive inhibition of rhDPP IV. DSP-7238 did not inhibit DPP IV-related enzymes including DPP8, DPP9, DPP II and FAPalpha, whereas vildagliptin and saxagliptin showed inhibition of DPP8 and DPP9. Inhibition of glucagon-like peptide-1 (GLP-1) degradation by DSP-7238 was apparently more potent than its inhibition of chemokine (C-X-C motif) ligand 10 (IP-10) or chemokine (C-X-C motif) ligand 12 (SDF-1alpha) degradation. In contrast, vildagliptin and saxagliptin showed similar degree of inhibition of degradation for all the substrates tested. Compared to treatment with the vehicle, single oral administration of DSP-7238 dose-dependently decreased plasma DPP IV activity and improved glucose tolerance in DIO mice. In addition, DSP-7238 significantly decreased HbA1c and ameliorated pancreatic damage following 11 weeks of chronic treatment in HFD/STZ mice. We have shown in this study that DSP-7238 is a potent DPP IV inhibitor that has high specificity for DPP IV and substrate selectivity against GLP-1. We have also found that chronic treatment with DSP-7238 improves glycaemic control and ameliorates beta-cell damage in a mouse model with impaired insulin sensitivity and secretion. These findings indicate that DSP-7238 may be a new therapeutic agent for the treatment of type 2 diabetes.

Differential effects of PPAR-{gamma} activation versus chemical or genetic reduction of DPP-4 activity on bone quality in mice.

PubMed

Kyle, Kimberly A; Willett, Thomas L; Baggio, Laurie L; Drucker, Daniel J; Grynpas, Marc D

2011-02-01

Patients with type 2 diabetes mellitus have an increased risk of fracture that can be further exacerbated by thiazolidinediones. A new class of antidiabetic agents control glucose through reduction of dipeptidyl peptidase-4 (DPP-4) activity; however the importance of DPP-4 for the control of bone quality has not been extensively characterized. We compared the effects of the thiazolidinedione pioglitazone and the DPP-4 inhibitor sitagliptin on bone quality in high-fat diet (HFD)-fed wild-type mice. In complementary studies, we examined bone quality in Dpp4(+/+) vs. Dpp4(-/-) mice. Pioglitazone produced yellow bones with greater bone marrow adiposity and significantly reduced vertebral bone mechanics in male, female, and ovariectomized (OVX) HFD fed female mice. Pioglitazone negatively affected vertebral volumetric bone mineral density, trabecular architecture, and mineral apposition rate in male mice. Sitagliptin treatment of HFD-fed wild-type mice significantly improved vertebral volumetric bone mineral density and trabecular architecture in female mice, but these improvements were lost in females after OVX. Genetic inactivation of Dpp4 did not produce a major bone phenotype in male and female Dpp4(-/-) mice; however, OVX Dpp4(-/-) mice exhibited significantly reduced femoral size and mechanics. These findings delineate the skeletal consequences of pharmacological and genetic reduction of DPP-4 activity and reveal significant differences in the effects of pioglitazone vs. sitagliptin vs. genetic Dpp4 inactivation on bone mechanics in mice.

Applying the COM-B model to creation of an IT-enabled health coaching and resource linkage program for low-income Latina moms with recent gestational diabetes: the STAR MAMA program.

PubMed

Handley, Margaret A; Harleman, Elizabeth; Gonzalez-Mendez, Enrique; Stotland, Naomi E; Althavale, Priyanka; Fisher, Lawrence; Martinez, Diana; Ko, Jocelyn; Sausjord, Isabel; Rios, Christina

2016-05-18

One of the fastest growing risk groups for early onset of diabetes is women with a recent pregnancy complicated by gestational diabetes, and for this group, Latinas are the largest at-risk group in the USA. Although evidence-based interventions, such as the Diabetes Prevention Program (DPP), which focuses on low-cost changes in eating, physical activity and weight management can lower diabetes risk and delay onset, these programs have yet to be tailored to postpartum Latina women. This study aims to tailor a IT-enabled health communication program to promote DPP-concordant behavior change among postpartum Latina women with recent gestational diabetes. The COM-B model (incorporating Capability, Opportunity, and Motivational behavioral barriers and enablers) and the Behavior Change Wheel (BCW) framework, convey a theoretically based approach for intervention development. We combined a health literacy-tailored health IT tool for reaching ethnic minority patients with diabetes with a BCW-based approach to develop a health coaching intervention targeted to postpartum Latina women with recent gestational diabetes. Current evidence, four focus groups (n = 22 participants), and input from a Regional Consortium of health care providers, diabetes experts, and health literacy practitioners informed the intervention development. Thematic analysis of focus group data used the COM-B model to determine content. Relevant cultural, theoretical, and technological components that underpin the design and development of the intervention were selected using the BCW framework. STAR MAMA delivers DPP content in Spanish and English using health communication strategies to: (1) validate the emotions and experiences postpartum women struggle with; (2) encourage integration of prevention strategies into family life through mothers becoming intergenerational custodians of health; and (3) increase social and material supports through referral to social networks, health coaches, and community resources. Feasibility, acceptability, and health-related outcomes (weight loss, physical activity, consumption of healthy foods, breastfeeding, and glucose screening) will be evaluated at 9 months postpartum using a randomized controlled trial design. STAR MAMA provides a DPP-based intervention that integrates theory-based design steps. Through systematic use of behavioral theory to inform intervention development, STAR MAMA may represent a strategy to develop health IT intervention tools to meet the needs of diverse populations. ClinicalTrials.gov NCT02240420.

Circulating dipeptidyl peptidase-4 activity correlates with measures of hepatocyte apoptosis and fibrosis in non-alcoholic fatty liver disease in type 2 diabetes mellitus and obesity: A dual cohort cross-sectional study.

PubMed

Williams, Kathryn H; Vieira De Ribeiro, Ana Júlia; Prakoso, Emilia; Veillard, Anne-Sophie; Shackel, Nicholas A; Brooks, Belinda; Bu, Yangmin; Cavanagh, Erika; Raleigh, Jim; McLennan, Susan V; McCaughan, Geoffrey W; Keane, Fiona M; Zekry, Amany; Gorrell, Mark D; Twigg, Stephen M

2015-11-01

Intrahepatic expression of dipeptidyl peptidase-4 (DPP4), and circulating DPP4 (cDPP4) levels and its enzymatic activity, are increased in non-alcoholic fatty liver disease (NAFLD) and in type 2 diabetes mellitus and/or obesity. DPP4 has been implicated as a causative factor in NAFLD progression but few studies have examined associations between cDPP4 activity and NAFLD severity in humans. This study aimed to examine the relationship of cDPP4 activity with measures of liver disease severity in NAFLD in subjects with diabetes and/or obesity. cDPP4 was measured in 106 individuals with type 2 diabetes who had transient elastography (Cohort 1) and 145 individuals with morbid obesity who had liver biopsy (Cohort 2). Both cohorts had caspase-cleaved keratin-18 (ccK18) measured as a marker of apoptosis. Natural log increases in cDPP4 activity were associated with increasing quartiles of ccK18 (Cohorts 1 and 2) and with median liver stiffness ≥10.3 kPa (Cohort 1) and significant fibrosis (F ≥ 2) on liver biopsy (Cohort 2). In diabetes and/or obesity, cDPP4 activity is associated with current apoptosis and liver fibrosis. Given the pathogenic mechanisms by which DPP4 may progress NAFLD, measurement of cDPP4 activity may have utility to predict disease progression and DPP4 inhibition may improve liver histology over time. © 2014 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Boundary Dpp promotes growth of medial and lateral regions of the Drosophila wing

PubMed Central

Barrio, Lara; Milán, Marco

2017-01-01

The gradient of Decapentaplegic (Dpp) in the Drosophila wing has served as a paradigm to characterize the role of morphogens in regulating patterning. However, the role of this gradient in regulating tissue size is a topic of intense debate as proliferative growth is homogenous. Here, we combined the Gal4/UAS system and a temperature-sensitive Gal80 molecule to induce RNAi-mediated depletion of dpp and characterise the spatial and temporal requirement of Dpp in promoting growth. We show that Dpp emanating from the AP compartment boundary is required throughout development to promote growth by regulating cell proliferation and tissue size. Dpp regulates growth and proliferation rates equally in central and lateral regions of the developing wing appendage and reduced levels of Dpp affects similarly the width and length of the resulting wing. We also present evidence supporting the proposal that graded activity of Dpp is not an absolute requirement for wing growth. DOI: http://dx.doi.org/10.7554/eLife.22013.001 PMID:28675372

Association of DPP4 Gene Polymorphisms with Type 2 Diabetes Mellitus in Malaysian Subjects

PubMed Central

Ahmed, Radwan H.; Huri, Hasniza Zaman; Al-Hamodi, Zaid; Salem, Sameer D.; Al-absi, Boshra; Muniandy, Sekaran

2016-01-01

Background Genetic polymorphisms of the Dipeptidyl Peptidase 4 (DPP4) gene may play a role in the etiology of type 2 diabetes mellitus (T2DM). This study aimed to investigate the possible association of single nucleotide polymorphisms (SNPs) of the DPP4 gene in Malaysian subjects with T2DM and evaluated whether they had an effect on the serum levels of soluble dipeptidyl peptidase 4 (sDPP-IV). Method Ten DPP4 SNPs were genotyped by TaqMan genotyping assays in 314 subjects with T2DM and 235 controls. Of these, 71 metabolic syndrome (MetS) subjects were excluded from subsequent analysis. The odds ratios (ORs) and their 95% confidence interval (CIs) were calculated using multiple logistic regression for the association between the SNPs of DPP4 and T2DM. In addition, the serum levels of sDPP-IV were investigated to evaluate the association of the SNPs of DPP4 with the sDPP-IV levels. Results Dominant, recessive, and additive genetic models were employed to test the association of DPP4 polymorphisms with T2DM, after adjusting for age, race, gender and BMI. The rs12617656 was associated with T2DM in Malaysian subjects in the recessive genetic model (OR = 1.98, p = 0.006), dominant model (OR = 1.95, p = 0.008), and additive model (OR = 1.63, p = 0.001). This association was more pronounced among Malaysian Indians, recessive (OR = 3.21, p = 0.019), dominant OR = 3.72, p = 0.003) and additive model (OR = 2.29, p = 0.0009). The additive genetic model showed that DPP4 rs4664443 and rs7633162 polymorphisms were associated with T2DM (OR = 1.53, p = 0.039), and (OR = 1.42, p = 0.020), respectively. In addition, the rs4664443 G>A polymorphism was associated with increased sDPP-IV levels (p = 0.042) in T2DM subjects. Conclusions DPP4 polymorphisms were associated with T2DM in Malaysian subjects, and linked to variations in sDPP-IV levels. In addition, these associations were more pronounced among Malaysian Indian subjects. PMID:27111895

Association of DPP4 Gene Polymorphisms with Type 2 Diabetes Mellitus in Malaysian Subjects.

PubMed

Ahmed, Radwan H; Huri, Hasniza Zaman; Al-Hamodi, Zaid; Salem, Sameer D; Al-Absi, Boshra; Muniandy, Sekaran

2016-01-01

Genetic polymorphisms of the Dipeptidyl Peptidase 4 (DPP4) gene may play a role in the etiology of type 2 diabetes mellitus (T2DM). This study aimed to investigate the possible association of single nucleotide polymorphisms (SNPs) of the DPP4 gene in Malaysian subjects with T2DM and evaluated whether they had an effect on the serum levels of soluble dipeptidyl peptidase 4 (sDPP-IV). Ten DPP4 SNPs were genotyped by TaqMan genotyping assays in 314 subjects with T2DM and 235 controls. Of these, 71 metabolic syndrome (MetS) subjects were excluded from subsequent analysis. The odds ratios (ORs) and their 95% confidence interval (CIs) were calculated using multiple logistic regression for the association between the SNPs of DPP4 and T2DM. In addition, the serum levels of sDPP-IV were investigated to evaluate the association of the SNPs of DPP4 with the sDPP-IV levels. Dominant, recessive, and additive genetic models were employed to test the association of DPP4 polymorphisms with T2DM, after adjusting for age, race, gender and BMI. The rs12617656 was associated with T2DM in Malaysian subjects in the recessive genetic model (OR = 1.98, p = 0.006), dominant model (OR = 1.95, p = 0.008), and additive model (OR = 1.63, p = 0.001). This association was more pronounced among Malaysian Indians, recessive (OR = 3.21, p = 0.019), dominant OR = 3.72, p = 0.003) and additive model (OR = 2.29, p = 0.0009). The additive genetic model showed that DPP4 rs4664443 and rs7633162 polymorphisms were associated with T2DM (OR = 1.53, p = 0.039), and (OR = 1.42, p = 0.020), respectively. In addition, the rs4664443 G>A polymorphism was associated with increased sDPP-IV levels (p = 0.042) in T2DM subjects. DPP4 polymorphisms were associated with T2DM in Malaysian subjects, and linked to variations in sDPP-IV levels. In addition, these associations were more pronounced among Malaysian Indian subjects.

Tuning the electrical conductance of metalloporphyrin supramolecular wires

NASA Astrophysics Data System (ADS)

Noori, Mohammed; Aragonès, Albert C.; di Palma, Giuseppe; Darwish, Nadim; Bailey, Steven W. D.; Al-Galiby, Qusiy; Grace, Iain; Amabilino, David B.; González-Campo, Arántzazu; Díez-Pérez, Ismael; Lambert, Colin J.

2016-11-01

In contrast with conventional single-molecule junctions, in which the current flows parallel to the long axis or plane of a molecule, we investigate the transport properties of M(II)-5,15-diphenylporphyrin (M-DPP) single-molecule junctions (M=Co, Ni, Cu, or Zn divalent metal ions), in which the current flows perpendicular to the plane of the porphyrin. Novel STM-based conductance measurements combined with quantum transport calculations demonstrate that current-perpendicular-to-the-plane (CPP) junctions have three-orders-of-magnitude higher electrical conductances than their current-in-plane (CIP) counterparts, ranging from 2.10-2 G0 for Ni-DPP up to 8.10-2 G0 for Zn-DPP. The metal ion in the center of the DPP skeletons is strongly coordinated with the nitrogens of the pyridyl coated electrodes, with a binding energy that is sensitive to the choice of metal ion. We find that the binding energies of Zn-DPP and Co-DPP are significantly higher than those of Ni-DPP and Cu-DPP. Therefore when combined with its higher conductance, we identify Zn-DPP as the favoured candidate for high-conductance CPP single-molecule devices.

Comparative Studies on Thermal, Mechanical, and Flame Retardant Properties of PBT Nanocomposites via Different Oxidation State Phosphorus-Containing Agents Modified Amino-CNTs.

PubMed

Zhu, San-E; Wang, Li-Li; Chen, Hao; Yang, Wei; Yuen, Anthony Chun-Yin; Chen, Timothy Bo-Yuan; Luo, Cheng; Bi, Wen-Mei; Hu, En-Zhu; Zhang, Jian; Si, Jing-Yu; Lu, Hong-Dian; Hu, Kun-Hong; Chan, Qing Nian; Yeoh, Guan Heng

2018-01-26

High-performance poly(1,4-butylene terephthalate) (PBT) nanocomposites have been developed via the consideration of phosphorus-containing agents and amino-carbon nanotube (A-CNT). One-pot functionalization method has been adopted to prepare functionalized CNTs via the reaction between A-CNT and different oxidation state phosphorus-containing agents, including chlorodiphenylphosphine (DPP-Cl), diphenylphosphinic chloride (DPP(O)-Cl), and diphenyl phosphoryl chloride (DPP(O₃)-Cl). These functionalized CNTs, DPP(O x )-A-CNTs ( x = 0, 1, 3), were, respectively, mixed with PBT to obtain the CNT-based polymer nanocomposites through a melt blending method. Scanning electron microscope observations demonstrated that DPP(O x )-A-CNT nanoadditives were homogeneously distributed within PBT matrix compared to A-CNT. The incorporation of DPP(O x )-A-CNT improved the thermal stability of PBT. Moreover, PBT/DPP(O₃)-A-CNT showed the highest crystallization temperature and tensile strength, due to the superior dispersion and interfacial interactions between DPP(O₃)-A-CNT and PBT. PBT/DPP(O)-A-CNT exhibited the best flame retardancy resulting from the excellent carbonization effect. The radicals generated from decomposed polymer were effectively trapped by DPP(O)-A-CNT, leading to the reduction of heat release rate, smoke production rate, carbon dioxide and carbon monoxide release during cone calorimeter tests.

Discovery of 2-[4-{{2-(2S,5R)-2-cyano-5-ethynyl-1-pyrrolidinyl]-2-oxoethyl]amino]- 4-methyl-1-piperidinyl]-4-pyridinecarboxylic acid (ABT-279): a very potent, selective, effective, and well-tolerated inhibitor of dipeptidyl peptidase-IV, useful for the treatment of diabetes.

PubMed

Madar, David J; Kopecka, Hana; Pireh, Daisy; Yong, Hong; Pei, Zhonghua; Li, Xiaofeng; Wiedeman, Paul E; Djuric, Stevan W; Von Geldern, Thomas W; Fickes, Michael G; Bhagavatula, Lakshmi; McDermott, Todd; Wittenberger, Steven; Richards, Steven J; Longenecker, Kenton L; Stewart, Kent D; Lubben, Thomas H; Ballaron, Stephen J; Stashko, Michael A; Long, Michelle A; Wells, Heidi; Zinker, Bradley A; Mika, Amanda K; Beno, David W A; Kempf-Grote, Anita J; Polakowski, James; Segreti, Jason; Reinhart, Glenn A; Fryer, Ryan M; Sham, Hing L; Trevillyan, James M

2006-10-19

Dipeptidyl peptidase-IV (DPP-IV) inhibitors are poised to be the next major drug class for the treatment of type 2 diabetes. Structure-activity studies of substitutions at the C5 position of the 2-cyanopyrrolidide warhead led to the discovery of potent inhibitors of DPP-IV that lack activity against DPP8 and DPP9. Further modification led to an extremely potent (Ki(DPP)(-)(IV) = 1.0 nM) and selective (Ki(DPP8) > 30 microM; Ki(DPP9) > 30 microM) clinical candidate, ABT-279, that is orally available, efficacious, and remarkably safe in preclinical safety studies.

Diabetes Prevention Program (DPP)

MedlinePlus

... la salud en español Health Statistics Healthy Moments Radio Broadcast Clinical Trials For Health Professionals Diabetes Discoveries & ... la salud en español Health Statistics Healthy Moments Radio Broadcast Clinical Trials For Health Professionals Diabetes Discoveries & ...

Use of SGLT2 inhibitors for diabetes and risk of infection: Analysis using general practice records from the NPS MedicineWise MedicineInsight program.

PubMed

Gadzhanova, Svetla; Pratt, Nicole; Roughead, Elizabet

2017-08-01

To explore the feasibility of MedicineInsight data to support risk management plan evaluation, focusing on sodium glucose co-transporter 2 (SGLT2) inhibitors for type 2 diabetes. A retrospective study using de-identified electronic general practitioner records. Patients who initiated SGLT2 inhibitor between 1 Jan 2012 to 1 Sep 2015 were compared to patients who initiated dipeptidyl peptidase 4 (DPP-4) inhibitors. The two cohorts were followed-up for six months. Risk of urinary-tract (UT) and genital infections was evaluated. The indication for use of SGLT2 inhibitors, recommended prior diabetes therapies and recommended monitoring were investigates. There were 1977 people in the SGLT2 cohort (with 93% initiated on dapagliflozin) and 1964 people in the DPP-4 cohort. Of the SGLT2 initiators, 54% had a documented indication for use as type 2 diabetes; 86% had used metformin and/or a sulfonylurea in the prior 12months. Renal function monitoring was documented for only 25% in the 6months initiation. The frequency of UTI in the 6months post SGLT2 initiation was not significantly increased compared to the DPP-4 cohort (3.6%vs 4.9%; aHR=0.90, 95% CI 0.66-1.24). Genital infection were more frequent in the SGLT2 than in the DPP-4 cohort (2.9% vs 0.9%, aHR=3.50, 95% CI 1.95-5.89). Similar to existing evidence, we found a higher risk of genital infection associated with SGLT2 inhibitors (primarily dapagliflozin) but no increased risk of UTIs compared to DPP-4 use. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

The Effects of Aerobic Exercises and 25(OH) D Supplementation on GLP1 and DPP4 Level in Type II Diabetic Patients.

PubMed

Rahimi, Naser; Samavati Sharif, Mohammad Ali; Goharian, Amir Reza; Pour, Ali Heidarian

2017-01-01

The purpose of this study was to investigate the effects of an 8-week aerobic exercise and supplementation of 25(OH)D3 on GLP1 and DDP4 levels in men with type II diabetes. In this semiexperimental research, among 40-60-year-old men with type II diabetes who were referred to the diabetic center of Isabn-E Maryam hospital in Isfahan; of whom, 48 patients were voluntarily accepted and then were randomly divided into 4 groups: aerobic exercise group, aerobic exercise with 25(OH) D supplement group, 25(OH) D supplement group, and the control group. An aerobic exercise program was conducted for 8 weeks (3 sessions/week, each session 60 to75 min with 60-80% HRmax). The supplement user group received 50,000 units of oral Vitamin D once weekly for 8 weeks. The GLP1, DPP4, and 25(OH) D levels were measured before and after the intervention. At last, the data were statistically analyzed using the ANCOVA and post hoc test of least significant difference. The results of ANCOVA showed a significant difference between the GLP1 and DPP4 levels in aerobic exercise with control group while these changes were not statistically significant between the 25(OH) D supplement group with control group ( P < 0.05). Aerobic exercises have resulted an increase in GLP1 level and a decrease in DPP4 level. However, consumption of Vitamin D supplement alone did not cause any changes in GLP1and DPP4 levels but led to an increase in 25-hydroxy Vitamin D level.

Dpp signaling inhibits proliferation in the Drosophila wing by Omb-dependent regional control of bantam.

PubMed

Zhang, Xubo; Luo, Dan; Pflugfelder, Gert O; Shen, Jie

2013-07-01

The control of organ growth is a fundamental aspect of animal development but remains poorly understood. The morphogen Dpp has long been considered as a general promoter of cell proliferation during Drosophila wing development. It is an ongoing debate whether the Dpp gradient is required for the uniform cell proliferation observed in the wing imaginal disc. Here, we investigated how the Dpp signaling pathway regulates proliferation during wing development. By systematic manipulation of Dpp signaling we observed that it controls proliferation in a region-specific manner: Dpp, via omb, promoted proliferation in the lateral and repressed proliferation in the medial wing disc. Omb controlled the regional proliferation rate by oppositely regulating transcription of the microRNA gene bantam in medial versus lateral wing disc. However, neither the Dpp nor Omb gradient was essential for uniform proliferation along the anteroposterior axis.

Recent progress of the development of dipeptidyl peptidase-4 inhibitors for the treatment of type 2 diabetes mellitus.

PubMed

Li, Ning; Wang, Li-Jun; Jiang, Bo; Li, Xiang-Qian; Guo, Chuan-Long; Guo, Shu-Ju; Shi, Da-Yong

2018-05-10

Diabetes is a fast growing chronic metabolic disorder around the world. Dipeptidyl peptidase-4 (DPP-4) is a new promising target during type 2 diabetes glycemic control. Thus, a number of potent DPP-4 inhibitors were developed and play a rapidly evolving role in the management of type 2 diabetes in recent years. This article reviews the development of synthetic and natural DPP-4 inhibitors from 2012 to 2017 and provides their physico-chemical properties, biological activities against DPP-4 and selectivity over dipeptidyl peptidase-8/9. Moreover, the glucose-lowering mechanisms and the active site of DPP-4 are also discussed. We also discuss strategies and structure-activity relationships for identifying potent DPP-4 inhibitors, which will provide useful information for developing potent DPP-4 drugs as type 2 diabtes treatments. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Decapentaplegic and growth control in the developing Drosophila wing.

PubMed

Akiyama, Takuya; Gibson, Matthew C

2015-11-19

As a central model for morphogen action during animal development, the bone morphogenetic protein 2/4 (BMP2/4)-like ligand Decapentaplegic (Dpp) is proposed to form a long-range signalling gradient that directs both growth and pattern formation during Drosophila wing disc development. While the patterning role of Dpp secreted from a stripe of cells along the anterior-posterior compartmental boundary is well established, the mechanism by which a Dpp gradient directs uniform cell proliferation remains controversial and poorly understood. Here, to determine the precise spatiotemporal requirements for Dpp during wing disc development, we use CRISPR-Cas9-mediated genome editing to generate a flippase recognition target (FRT)-dependent conditional null allele. By genetically removing Dpp from its endogenous stripe domain, we confirm the requirement of Dpp for the activation of a downstream phospho-Mothers against dpp (p-Mad) gradient and the regulation of the patterning targets spalt (sal), optomotor blind (omb; also known as bifid) and brinker (brk). Surprisingly, however, third-instar wing blade primordia devoid of compartmental dpp expression maintain relatively normal rates of cell proliferation and exhibit only mild defects in growth. These results indicate that during the latter half of larval development, the Dpp morphogen gradient emanating from the anterior-posterior compartment boundary is not directly required for wing disc growth.

Reduction of soluble dipeptidyl peptidase 4 levels in plasma of patients infected with Middle East respiratory syndrome coronavirus.

PubMed

Inn, Kyung-Soo; Kim, Yuri; Aigerim, Abdimadiyeva; Park, Uni; Hwang, Eung-Soo; Choi, Myung-Sik; Kim, Yeon-Sook; Cho, Nam-Hyuk

2018-05-01

Dipeptidyl peptidase 4 (DPP4) is a receptor for MERS-CoV. The soluble form of DPP4 (sDPP4) circulates systematically and can competitively inhibit MERS-CoV entry into host cells. Here, we measured the concentration of sDPP4 in the plasma and sputa of 14 MERS-CoV-infected patients of various degrees of disease severity. The concentration of sDPP4 in the plasma of MERS patients (474.76 ± 108.06 ng/ml) was significantly lower than those of healthy controls (703.42 ± 169.96 ng/ml), but there were no significant differences among the patient groups. Interestingly, plasma levels of IL-10 and EGF were negatively and positively correlated with sDPP4 concentrations, respectively. The sDPP4 levels in sputa were less than 300 ng/ml. Viral infection was inhibited by 50% in the presence of more than 8000 ng/ml of sDPP4. Therefore, sDPP4 levels in the plasma of MERS patients are significantly reduced below the threshold needed to exert an antiviral effect against MERS-CoV infection. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Structural Biology and Molecular Modeling in the Design of Novel DPP-4 Inhibitors

NASA Astrophysics Data System (ADS)

Scapin, Giovanna

Inhibition of dipeptidyl peptidase IV (DPP-4) is a promising new approach for the treatment of type 2 diabetes. DPP-4 is the enzyme responsible for inactivating the incretin hormones glucagon-like peptide 1 (GLP-1) and glucose dependent insulinotropic polypeptide (GIP), two hormones that play important roles in glucose homeostasis. The potent, orally bioavailable and highly selective small molecule DPP-4 inhibitor sitagliptin has been approved by the FDA as novel drug for the treatment of type 2 diabetes. The comparison between the binding mode of sitagliptin (a β-amino acid) and that of a second class of inhibitors (α-amino acid-based) initially led to the successful identification and design of structurally diverse and highly potent DPP-4 inhibitors. Further analysis of the crystal structure of sitagliptin bound to DPP-4 suggested that the central β-amino butanoyl moiety could be replaced by a rigid group. This was confirmed by molecular modeling, and the resulting cyclohexylamine analogs were synthesized and found to be potent DPP-4 inhibitors. However, the triazolopyrazine was predicted to be distorted in order to fit in the binding pocket, and the crystal structure showed that multiple conformations exist for this moiety. Additional molecular modeling studies were then used to improve potency of the cyclohexylamine series. In addition, a 3-D QSAR method was used to gain insight for reducing off-target DPP-8/9 activities. Novel compounds were thus synthesized and found to be potent DPP-4 inhibitors. Two compounds in particular were designed to be highly selective against off-target "DPP-4 Activity- and/or Structure Homologues" (DASH) enzymes while maintaining potency against DPP-4.

Unique and Highly Selective Anticytomegalovirus Activities of Artemisinin-Derived Dimer Diphenyl Phosphate Stem from Combination of Dimer Unit and a Diphenyl Phosphate Moiety

PubMed Central

He, Ran; Forman, Michael; Mott, Bryan T.; Venkatadri, Rajkumar; Posner, Gary H.

2013-01-01

We report that the artemisinin-derived dimer diphenyl phosphate (DPP; dimer 838) is the most selective inhibitor of human cytomegalovirus (CMV) replication among a series of artemisinin-derived monomers and dimers. Dimer 838 was also unique in being an irreversible CMV inhibitor. The peroxide unit within artemisinins' chemical structures is critical to their activities, and its absence results in loss of anti-CMV activities. Surprisingly, the deoxy dimer of 838 retained modest anti-CMV activity, suggesting that the DPP moiety of dimer 838 contributes to its anti-CMV activities. DPP alone did not inhibit CMV replication, but triphenyl phosphate (TPP) had modest CMV inhibition, although its selectivity index was low. Artemisinin DPP derivatives dimer 838 and monomer diphenyl phosphate (compound 558) showed stronger CMV inhibition and a higher selectivity index than their analogs lacking the DPP unit. An add-on and removal assay revealed that removing DPP derivatives (compounds 558 and 838) but not the non-DPP backbones (artesunate and compound 606) at 24 h postinfection (hpi) already resulted in dominant CMV inhibition. CMV inhibition was fully irreversible with 838 and partially irreversible with 558, while non-DPP artemisinins were reversible inhibitors. While all artemisinin derivatives and TPP reduced the expression of the CMV immediate early 2 (IE2), UL44, and pp65 proteins at or after 48 hpi, only TPP inhibited the expression of both IE1 and IE2. Combination of a non-DPP dimer (compound 606) with TPP was synergistic in CMV inhibition, while ganciclovir and TPP were additive. Although TPP shared structural similarity with monomer DPP (compound 558) and dimer DPP (compound 838), its pattern of CMV inhibition was significantly different from the patterns of the artemisinins. These findings demonstrate that the DPP group contributes to the unique activities of compound 838. PMID:23774439

Soluble DPP-4 up-regulates toll-like receptors and augments inflammatory reactions, which are ameliorated by vildagliptin or mannose-6-phosphate.

PubMed

Lee, Dong-Sung; Lee, Eun-Sol; Alam, Md Morshedul; Jang, Jun-Hyeog; Lee, Ho-Sub; Oh, Hyuncheol; Kim, Youn-Chul; Manzoor, Zahid; Koh, Young-Sang; Kang, Dae-Gil; Lee, Dae Ho

2016-02-01

Studies have shown that dipeptidyl peptidase-4 (DPP-4) inhibitors have anti-inflammatory effects. Soluble DPP-4 (sDPP-4) has been considered as an adipokine of which actions need to be further characterized. We investigated the pro-inflammatory actions of sDPP-4 and the anti-inflammatory effects of DPP-4 inhibition, using vildagliptin, as an enzymatic inhibitor, and mannose-6-phosphate (M6P) as a competitive binding inhibitor. In lipopolysaccharide (LPS)-stimulated RAW264.7 cells, vildagliptin suppressed the increased expression of inducible nitric oxide synthase (iNOS) and phosphorylated JNK (pJNK), activation of the NF-κB pathway, and the resultant NO and proinflammatory cytokine production. Although sDPP-4 alone did not affect the protein level of iNOS or pJNK or the production of NO in RAW264.7 cells, it did amplify iNOS expression, NO responses, and proinflammatory cytokine production in LPS-stimulated RAW264 cells. As a probable mechanism, we found that sDPP-4 caused dose-dependent increases in the expression levels of toll-like receptor 4 (TLR4) and TLR2 in RAW264.7 cells, and that these alterations were inhibited by vildagliptin, M6P, or bisindolylmaleimide II, a protein kinase C inhibitor. Either vildagliptin or M6P suppressed iNOS expression and NO and cytokine production in LPS+DPP-4-co-stimulated macrophages, while combined treatment of the co-stimulated cells with both agents had increased anti-inflammatory effects compared with either treatment alone. Intravenous injection of sDPP-4 to C57BL/6J mice increased the expression of both TLRs in kidney and white adipose tissues. Our findings suggest that sDPP-4 enhances inflammatory actions via TLR pathway, while DPP-4 inhibition with either an enzymatic or binding inhibitor has anti-inflammatory effects. Copyright © 2015 Elsevier Inc. All rights reserved.

Immunohistochemical localization of DPP10 in rat brain supports the existence of a Kv4/KChIP/DPPL ternary complex in neurons.

PubMed

Wang, Wan-Chen; Cheng, Chau-Fu; Tsaur, Meei-Ling

2015-03-01

Subthreshold A-type K(+) currents (ISA s) have been recorded from the cell bodies of hippocampal and neocortical interneurons as well as neocortical pyramidal neurons. Kv4 channels are responsible for the somatodendritic ISA s. It has been proposed that neuronal Kv4 channels are ternary complexes including pore-forming Kv4 subunits, K(+) channel-interacting proteins (KChIPs), and dipeptidyl peptidase-like proteins (DPPLs). However, colocalization evidence was still lacking. The distribution of DPP10 mRNA in rodent brain has been reported but its protein localization remains unknown. In this study, we generated a DPP10 antibody to label DPP10 protein in adult rat brain by immunohistochemistry. Absent from glia, DPP10 proteins appear mainly in the cell bodies of DPP10(+) neurons, not only at the plasma membrane but also in the cytoplasm. At least 6.4% of inhibitory interneurons in the hippocampus coexpressed Kv4.3, KChIP1, and DPP10, with the highest density in the CA1 strata alveus/oriens/pyramidale and the dentate hilus. Colocalization of Kv4.3/KChIP1/DPP10 was also detected in at least 6.9% of inhibitory interneurons scattered throughout the neocortex. Both hippocampal and neocortical Kv4.3/KChIP1/DPP10(+) inhibitory interneurons expressed parvalbumin or somatostatin, but not calbindin or calretinin. Furthermore, we found colocalization of Kv4.2/Kv4.3/KChIP3/DPP10 in neocortical layer 5 pyramidal neurons and olfactory bulb mitral cells. Together, although DPP10 is also expressed in some brain neurons lacking Kv4 (such as parvalbumin- and somatostatin-positive Golgi cells in the cerebellum), colocalization of DPP10 with Kv4 and KChIP at the plasma membrane of ISA -expressing neuron somata supports the existence of Kv4/KChIP/DPPL ternary complex in vivo. © 2014 Wiley Periodicals, Inc.

Influence of PNA containing 8-aza-7-deazaadenine on structure stability and binding affinity of PNA·DNA duplex: insights from thermodynamics, counter ion, hydration and molecular dynamics analysis.

PubMed

Gupta, Sharad K; Sur, Souvik; Prasad Ojha, Rajendra; Tandon, Vibha

2013-07-01

This paper describes the synthesis of a novel 8-aza-7-deazapurin-2,6-diamine (DPP)-containing peptide nucleic acid (PNA) monomer and Boc protecting group-based oligomerization of PNA, replacing adenine (A) with DPP monomers in the PNA strand. The PNA oligomers were synthesized against the biologically relevant SV40 promoter region (2494-AATTTTTTTTATTTA-2508) of pEGFP-N3 plasmid. The DPP-PNA·DNA duplex showed enhanced stability as compared to normal duplex (A-PNA·DNA). The electronic distribution of DPP monomer suggested that DPP had better electron donor properties over 2,6-diamino purine. UV melting and thermodynamic analysis revealed that the PNA oligomer containing a diaminopyrazolo(3,4-d)pyrimidine moiety (DPP) stabilized the PNA·DNA hybrids compared to A-PNA·DNA. DPP-PNA·DNA duplex showed higher water activity (Δnw = 38.5) in comparison to A-PNA·DNA duplex (Δnw = 14.5). The 50 ns molecular dynamics simulations of PNA·DNA duplex containing DPP or unmodified nucleobase-A showed average H-bond distances in the DPP-dT base pair of 2.90 Å (OH-N bond) and 2.91 Å (NH-N bond), which were comparably shorter than in the A-dT base pair, in which the average distances were 3.18 Å (OH-N bond) and 2.97 Å (NH-N bond), and there was one additional H-bond in the DPP-dT base pair of around 2.98 Å (O2H-N2 bond), supporting the higher stability of DPP-PNA·DNA. The analysis of molecular dynamics simulation data showed that the system binding free energy increased at a rate of approximately -4.5 kcal mol(-1) per DPP base of the PNA·DNA duplex. In summary, increased thermal stability, stronger hydrogen bonding and more stable conformation in the DPP-PNA·DNA duplex make it a better candidate as antisense/antigene therapeutic agents.

Serum Levels of Soluble CD26/Dipeptidyl Peptidase-IV in Type 2 Diabetes Mellitus and Its Association with Metabolic Syndrome and Therapy with Antidiabetic Agents in Malaysian Subjects.

PubMed

Ahmed, Radwan H; Huri, Hasniza Zaman; Al-Hamodi, Zaid; Salem, Sameer D; Muniandy, Sekaran

2015-01-01

A soluble form of CD26/dipeptidyl peptidase-IV (sCD26/DPP-IV) induces DPP-IV enzymatic activity that degrades incretin. We investigated fasting serum levels of sCD26/DPP-IV and active glucagon-like peptide-1 (GLP-1) in Malaysian patients with type 2 diabetes mellitus (T2DM) with and without metabolic syndrome (MetS), as well as the associations between sCD26/DPP-IV levels, MetS, and antidiabetic therapy. We assessed sCD26/DPP-IV levels, active GLP-1 levels, body mass index (BMI), glucose, insulin, A1c, glucose homeostasis indices, and lipid profiles in 549 Malaysian subjects (including 257 T2DM patients with MetS, 57 T2DM patients without MetS, 71 non-diabetics with MetS, and 164 control subjects without diabetes or metabolic syndrome). Fasting serum levels of sCD26/DPP-IV were significantly higher in T2DM patients with and without MetS than in normal subjects. Likewise, sCD26/DPP-IV levels were significantly higher in patients with T2DM and MetS than in non-diabetic patients with MetS. However, active GLP-1 levels were significantly lower in T2DM patients both with and without MetS than in normal subjects. In T2DM subjects, sCD26/DPP-IV levels were associated with significantly higher A1c levels, but were significantly lower in patients using monotherapy with metformin. In addition, no significant differences in sCD26/DPP-IV levels were found between diabetic subjects with and without MetS. Furthermore, sCD26/DPP-IV levels were negatively correlated with active GLP-1 levels in T2DM patients both with and without MetS. In normal subjects, sCD26/DPP-IV levels were associated with increased BMI, cholesterol, and LDL-cholesterol (LDL-c) levels. Serum sCD26/DPP-IV levels increased in T2DM subjects with and without MetS. Active GLP-1 levels decreased in T2DM patients both with and without MetS. In addition, sCD26/DPP-IV levels were associated with Alc levels and negatively correlated with active GLP-1 levels. Moreover, metformin monotherapy was associated with reduced sCD26/DPP-IV levels. In normal subjects, sCD26/DPP-IV levels were associated with increased BMI, cholesterol, and LDL-c.

Diketopyrrolopyrrole-based π-bridged donor-acceptor polymer for photovoltaic applications.

PubMed

Li, Wenting; Lee, Taegweon; Oh, Soong Ju; Kagan, Cherie R

2011-10-01

We report the synthesis, properties, and photovoltaic applications of a new conjugated copolymer (C12DPP-π-BT) containing a donor group (bithiophene) and an acceptor group (2,5-didodecylpyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione), bridged by a phenyl group. Using cyclic voltammetry, we found the energy levels of C12DPP-π-BT are intermediate to common electron donor and acceptor photovoltaic materials, poly (3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), respectively. Whereas P3HT and PCBM are exclusively electron donating or accepting, we predict C12DPP-π-BT may uniquely serve as either an electron donor or an acceptor when paired with PCBM or P3HT forming junctions with large built-in potentials. We confirmed the ambipolar nature of C12DPP-π-BT in space charge limited current measurements and in C12DPP-π-BT:PCBM and C12DPP-π-BT:P3HT bulk heterojunction solar cells, achieving power conversion efficiencies of 1.67% and 0.84%, respectively, under illumination of AM 1.5G (100 mW/cm(2)). Adding diiodooctane to C12DPP-π-BT:PCBM improved donor-acceptor inter-mixing and film uniformity, and therefore enhanced charge separation and overall device efficiency. Using higher-molecular-weight polymer C12DPP-π-BT in both C12DPP-π-BT:PCBM and C12DPP-π-BT:P3HT devices improved charge transport and hence the performance of the solar cells. In addition, we compared the structural and electronic properties of C12DPP-π-BT:PCBM and C12DPP-π-BT:P3HT blends, representing the materials classes of polymer:fullerene and polymer:polymer blends. In C12DPP-π-BT:PCBM blends, higher short circuit currents were obtained, consistent with faster charge transfer and balanced electron and hole transport, but lower open circuit voltages may be reduced by trap-assisted recombination and interfacial recombination losses. In contrast, C12DPP-π-BT:P3HT blends exhibit higher open circuit voltage, but short circuit currents were limited by charge transfer between the polymers. In conclusion, C12DPP-π-BT is a promising material with intrinsic ambipolar characteristics for organic photovoltaics and may operate as either a donor or acceptor in the design of bulk heterojunction solar cells. © 2011 American Chemical Society

High Gravity (g) Combustion

DTIC Science & Technology

2006-02-01

UNICORN (Unsteady Ignition and Combustion with Reactions) code10. Flame propagation in a tube that is 50-mm wide and 1000-mm long (similar to that...turbine engine manufacturers, estimating the primary zone space heating rate. Both combustion systems, from Company A and Company B, required a much...MBTU/atm-hr-ft3) Te m pe ra tu re R is e (K ) dP/P = 2% dP/P = 2.5% dP/P = 3% dP/P = 3.5% dP/P = 4% Company A Company B Figure 13: Heat Release Rate

DPP and DSP are Necessary for Maintaining TGF-β1 Activity in Dentin

PubMed Central

Yamakoshi, Y.; Kinoshita, S.; Izuhara, L.; Karakida, T.; Fukae, M.; Oida, S.

2014-01-01

Porcine dentin sialophosphoprotein (DSPP) is the most abundant non-collagenous protein in dentin. It is processed by proteases into 3 independent proteins: dentin sialoprotein (DSP), dentin glycoprotein (DGP), and dentin phosphoprotein (DPP). We fractionated DPP and DSP along with TGF-β activity by ion exchange (IE) chromatography from developing pig molars and measured their alkaline phosphatase (ALP)-stimulating activity in human periodontal (HPDL) cells with or without TGF-β receptor inhibitor. We then purified TGF-β-unbound or -bound DPP and DSP by reverse-phase high-performance liquid chromatography (RP-HPLC) using the ALP-HPDL system. The TGF-β isoform bound to DPP and DSP was identified as being TGF-β1 by both ELISA and LC-MS/MS analysis. We incubated carrier-free human recombinant TGF-β1 (CF-hTGF-β1) with TGF-β-unbound DPP or DSP and characterized the binding on IE-HPLC using the ALP-HPDL system. When only CF-hTGF-β1 was incubated, approximately 3.6% of the ALP-stimulating activity remained. DPP and DSP rescued the loss of TGF-β1 activity. Approximately 19% and 10% of the ALP stimulating activities were retained by the binding of TGF-β to DPP and DSP, respectively. The type I collagen infrequently bound to CF-hTGF-β1. We conclude that both DPP and DSP help retain TGF-β1 activity in porcine dentin. PMID:24799420

Purification, identification and molecular mechanism of two dipeptidyl peptidase IV (DPP-IV) inhibitory peptides from Antarctic krill (Euphausia superba) protein hydrolysate.

PubMed

Ji, Wei; Zhang, Chaohua; Ji, Hongwu

2017-10-01

Dipeptidyl peptidase IV (DPP-IV) played an important role in blood glucose regulation. Inhibition of DPP-IV may improve glycemic control in diabetics by preventing the rapid breakdown of incretin hormones and prolonging their physiological action. In this study, Antarctic krill (Euphausia superba) protein was hydrolyzed using animal proteolytic enzymes. The hydrolysate was purified sequentially by ultrafiltration, gel filtration chromatography and reversed phase high-performance liquid chromatography (RP-HPLC). DPP-IV inhibitory activity of the fractions achieved from Antarctic krill protein was determined by DPP-IV screening reagent kit. Two purified peptides were identified by Xevo G2-XS QTof mass spectrometer (QTOF-MS). One peptide purified was Ala-Pro (AP) with IC 50 values of 0.0530mg/mL, the other Ile-Pro-Ala (IPA) with IC 50 values of 0.0370mg/mL. They both exhibited strong DPP-IV inhibitory activity. The molecular docking analysis revealed that DPP-IV inhibition by AP and IPA was mainly due to formation of a strong interaction surface force with the 91-96 and 101-105 amino acids of the DPP-IV. Our results suggested that the protein hydrolysate from Antarctic krill can be considered as a promising natural source of DPP-IV inhibitory peptides in the management of diabetes. Copyright © 2017 Elsevier B.V. All rights reserved.

30 CFR 550.266 - After receiving the DPP or DOCD, what will BOEM do?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false After receiving the DPP or DOCD, what will BOEM do? 550.266 Section 550.266 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE... Review and Decision Process for the Dpp Or Docd § 550.266 After receiving the DPP or DOCD, what will BOEM...

30 CFR 250.266 - After receiving the DPP or DOCD, what will MMS do?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false After receiving the DPP or DOCD, what will MMS do? 250.266 Section 250.266 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR... Decision Process for the Dpp Or Docd § 250.266 After receiving the DPP or DOCD, what will MMS do? (a...

30 CFR 550.266 - After receiving the DPP or DOCD, what will BOEM do?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false After receiving the DPP or DOCD, what will BOEM do? 550.266 Section 550.266 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE... Review and Decision Process for the Dpp Or Docd § 550.266 After receiving the DPP or DOCD, what will BOEM...

30 CFR 550.266 - After receiving the DPP or DOCD, what will BOEM do?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false After receiving the DPP or DOCD, what will BOEM do? 550.266 Section 550.266 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE... Review and Decision Process for the Dpp Or Docd § 550.266 After receiving the DPP or DOCD, what will BOEM...

Quinoline-Flanked Diketopyrrolopyrrole Copolymers Breaking through Electron Mobility over 6 cm2 V-1 s-1 in Flexible Thin Film Devices.

PubMed

Ni, Zhenjie; Dong, Huanli; Wang, Hanlin; Ding, Shang; Zou, Ye; Zhao, Qiang; Zhen, Yonggang; Liu, Feng; Jiang, Lang; Hu, Wenping

2018-03-01

Herein, the design and synthesis of novel π-extended quinoline-flanked diketopyrrolopyrrole (DPP) [abbreviated as QDPP] motifs and corresponding copolymers named PQDPP-T and PQDPP-2FT for high performing n-type organic field-effect transistors (OFETs) in flexible organic thin film devices are reported. Serving as DPP-flankers in backbones, quinoline is found to effectively tune copolymer optoelectric properties. Compared with TDPP and pyridine-flanked DPP (PyDPP) analogs, widened bandgaps and strengthened electron deficiency are achieved. Moreover, both hole and electron mobility are improved two orders of magnitude compared to those of PyDPP analogs (PPyDPP-T and PPyDPP-2FT). Notably, featuring an all-acceptor-incorporated backbone, PQDPP-2FT exhibits electron mobility of 6.04 cm 2 V -1 s -1 , among the highest value in OFETs fabricated on flexible substrates to date. Moreover, due to the widened bandgap and strengthened electron deficiency of PQDPP, n-channel on/off ratio over 10 5 with suppressed hole transport is first realized in the ambipolar DPP-based copolymers. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Inwardly rectifying potassium channels influence Drosophila wing morphogenesis by regulating Dpp release.

PubMed

Dahal, Giri Raj; Pradhan, Sarala Joshi; Bates, Emily Anne

2017-08-01

Loss of embryonic ion channel function leads to morphological defects, but the underlying reason for these defects remains elusive. Here, we show that inwardly rectifying potassium (Irk) channels regulate release of the Drosophila bone morphogenetic protein Dpp in the developing fly wing and that this is necessary for developmental signaling. Inhibition of Irk channels decreases the incidence of distinct Dpp-GFP release events above baseline fluorescence while leading to a broader distribution of Dpp-GFP. Work by others in different cell types has shown that Irk channels regulate peptide release by modulating membrane potential and calcium levels. We found calcium transients in the developing wing, and inhibition of Irk channels reduces the duration and amplitude of calcium transients. Depolarization with high extracellular potassium evokes Dpp release. Taken together, our data implicate Irk channels as a requirement for regulated release of Dpp, highlighting the importance of the temporal pattern of Dpp presentation for morphogenesis of the wing. © 2017. Published by The Company of Biologists Ltd.

Fungal Mimicry of a Mammalian Aminopeptidase Disables Innate Immunity and Promotes Pathogenicity.

PubMed

Sterkel, Alana K; Lorenzini, Jenna L; Fites, J Scott; Subramanian Vignesh, Kavitha; Sullivan, Thomas D; Wuthrich, Marcel; Brandhorst, Tristan; Hernandez-Santos, Nydiaris; Deepe, George S; Klein, Bruce S

2016-03-09

Systemic fungal infections trigger marked immune-regulatory disturbances, but the mechanisms are poorly understood. We report that the pathogenic yeast of Blastomyces dermatitidis elaborates dipeptidyl-peptidase IVA (DppIVA), a close mimic of the mammalian ectopeptidase CD26, which modulates critical aspects of hematopoiesis. We show that, like the mammalian enzyme, fungal DppIVA cleaved C-C chemokines and GM-CSF. Yeast producing DppIVA crippled the recruitment and differentiation of monocytes and prevented phagocyte activation and ROS production. Silencing fungal DppIVA gene expression curtailed virulence and restored recruitment of CCR2(+) monocytes, generation of TipDC, and phagocyte killing of yeast. Pharmacological blockade of DppIVA restored leukocyte effector functions and stemmed infection, while addition of recombinant DppIVA to gene-silenced yeast enabled them to evade leukocyte defense. Thus, fungal DppIVA mediates immune-regulatory disturbances that underlie invasive fungal disease. These findings reveal a form of molecular piracy by a broadly conserved aminopeptidase during disease pathogenesis. Copyright © 2016 Elsevier Inc. All rights reserved.

Tuning the Photophysical Properties of Ru(II) Monometallic and Ru(II),Rh(III) Bimetallic Supramolecular Complexes by Selective Ligand Deuteration.

PubMed

Wagner, Alec T; Zhou, Rongwei; Quinn, Kevan S; White, Travis A; Wang, Jing; Brewer, Karen J

2015-07-02

A series of three new complexes of the design [(TL)2Ru(BL)](2+), two new complexes of the design [(TL)2Ru(BL)Ru(TL)2](4+), and three new complexes of the design [(TL)2Ru(BL)RhCl2(TL)](3+) (TL = bpy or d8-bpy; BL = dpp or d10-dpp; TL = terminal ligand; BL = bridging ligand; bpy = 2,2'-bipyridine; dpp = 2,3-bis(2-pyridyl)pyrazine) were synthesized and the (1)H NMR spectroscopy, electrochemistry, electronic absorbance spectroscopy, and photophysical properties studied. Incorporation of deuterated ligands into the molecular architecture simplifies the (1)H NMR spectra, allowing for complete (1)H assignment of [(d8-bpy)2Ru(dpp)](PF6)2 and partial assignment of [(bpy)2Ru(d10-dpp)](PF6)2. The electrochemistry for the deuterated and nondeuterated species showed nearly identical redox properties. Electronic absorption spectroscopy of the deuterated and nondeuterated complexes are superimposable with the lowest energy transition being Ru(dπ) → BL(π*) charge transfer in nature (BL = dpp or d10-dpp). Ligand deuteration impacts the excited-state properties with an observed increase in the quantum yield of emission (Φ(em)) and excited-state lifetime (τ) of the Ru(dπ) → d10-dpp(π*) triplet metal-to-ligand charge transfer ((3)MLCT) excited state when dpp is deuterated, and a decrease in the rate constant for nonradiative decay (knr). Choice of ligand deuteration between bpy and dpp strongly impacts the observed photophysical properties with BL = d10-dpp complexes showing an enhanced Φ(em) and τ, providing further support that the lowest electronic excited state populated via UV or visible excitation is the photoactive Ru(dπ) → dpp(π*) CT excited state. The Ru(II),Rh(III) complex incorporating the deuterated BL shows increased hydrogen production compared to the variants incorporating the protiated BL, while demonstrating identical dynamic quenching behaviors in the presence of sacrificial electron donor.

Unique Cardiac Purkinje Fiber Transient Outward Current β-Subunit Composition

PubMed Central

Xiao, Ling; Koopmann, Tamara T.; Ördög, Balázs; Postema, Pieter G.; Verkerk, Arie O.; Iyer, Vivek; Sampson, Kevin J.; Boink, Gerard J.J.; Mamarbachi, Maya A.; Varro, Andras; Jordaens, Luc; Res, Jan; Kass, Robert S.; Wilde, Arthur A.; Bezzina, C.R.; Nattel, Stanley

2015-01-01

Rationale A chromosomal haplotype producing cardiac overexpression of dipeptidyl peptidase-like protein-6 (DPP6) causes familial idiopathic ventricular fibrillation. The molecular basis of transient outward current (Ito) in Purkinje fibers (PFs) is poorly understood. We hypothesized that DPP6 contributes to PF Ito and that its overexpression might specifically alter PF Ito properties and repolarization. Objective To assess the potential role of DPP6 in PF Ito. Methods and Results Clinical data in 5 idiopathic ventricular fibrillation patients suggested arrhythmia origin in the PF-conducting system. PF and ventricular muscle Ito had similar density, but PF Ito differed from ventricular muscle in having tetraethylammonium sensitivity and slower recovery. DPP6 overexpression significantly increased, whereas DPP6 knockdown reduced, Ito density and tetraethylammonium sensitivity in canine PF but not in ventricular muscle cells. The K+-channel interacting β-subunit K+-channel interacting protein type-2, essential for normal expression of Ito in ventricular muscle, was weakly expressed in human PFs, whereas DPP6 and frequenin (neuronal calcium sensor-1) were enriched. Heterologous expression of Kv4.3 in Chinese hamster ovary cells produced small Ito; Ito amplitude was greatly enhanced by coexpression with K+-channel interacting protein type-2 or DPP6. Coexpression of DPP6 with Kv4.3 and K+-channel interacting protein type-2 failed to alter Ito compared with Kv4.3/K+-channel interacting protein type-2 alone, but DPP6 expression with Kv4.3 and neuronal calcium sensor-1 (to mimic PF Ito composition) greatly enhanced Ito compared with Kv4.3/neuronal calcium sensor-1 and recapitulated characteristic PF kinetic/pharmacological properties. A mathematical model of cardiac PF action potentials showed that Ito enhancement can greatly accelerate PF repolarization. Conclusions These results point to a previously unknown central role of DPP6 in PF Ito, with DPP6 gain of function selectively enhancing PF current, and suggest that a DPP6-mediated PF early-repolarization syndrome might be a novel molecular paradigm for some forms of idiopathic ventricular fibrillation. PMID:23532596

Multiprotein assembly of Kv4.2, KChIP3 and DPP10 produces ternary channel complexes with ISA-like properties.

PubMed

Jerng, Henry H; Kunjilwar, Kumud; Pfaffinger, Paul J

2005-11-01

Kv4 pore-forming subunits are the principal constituents of the voltage-gated K+ channel underlying somatodendritic subthreshold A-type currents (I(SA)) in neurones. Two structurally distinct types of Kv4 channel modulators, Kv channel-interacting proteins (KChIPs) and dipeptidyl-peptidase-like proteins (DPLs: DPP6 or DPPX, DPP10 or DPPY), enhance surface expression and modify functional properties. Since KChIP and DPL distributions overlap in the brain, we investigated the potential coassembly of Kv4.2, KChIP3 and DPL proteins, and the contribution of DPLs to ternary complex properties. Immunoprecipitation results show that KChIP3 and DPP10 associate simultaneously with Kv4.2 proteins in rat brain as well as heterologously expressing Xenopus oocytes, indicating Kv4.2 + KChIP3 + DPP10 multiprotein complexes. Consistent with ternary complex formation, coexpression of Kv4.2, KChIP3 and DPP10 in oocytes and CHO cells results in current waveforms distinct from the arithmetic sum of Kv4.2 + KChIP3 and Kv4.2 + DPP10 currents. Furthermore, the Kv4.2 + KChIP3 + DPP10 channels recover from inactivation very rapidly (tau(rec) approximately 18-26 ms), closely matching that of native I(SA) and significantly faster than the recovery of Kv4.2 + KChIP3 or Kv4.2 + DPP10 channels. For comparison, identical triple coexpression experiments were performed using DPP6 variants. While most results are similar, the Kv4.2 + KChIP3 + DPP6 channels exhibit inactivation that slows with increasing membrane potential, resulting in inactivation slower than that of Kv4.2 + KChIP3 + DPP10 channels at positive voltages. In conclusion, the native neuronal subthreshold A-type channel is probably a macromolecular complex formed from Kv4 and a combination of both KChIP and DPL proteins, with the precise composition of channel alpha and auxiliary subunits underlying tissue and regional variability in I(SA) properties.

DPP-4 inhibitor therapy and bone fractures in people with Type 2 diabetes - A systematic review and meta-analysis.

PubMed

Mamza, Jil; Marlin, Carol; Wang, Cai; Chokkalingam, Kamal; Idris, Iskandar

2016-06-01

Fracture risk is higher in older adults with Type 2 diabetes mellitus (T2DM). Oral glucose-lowering medications have different effects on bone metabolism. The purpose of this study is to appraise the evidence from literature and determine the effect of dipeptidyl peptidase-4 (DPP-4) inhibitor on the risk of developing bone fractures. Using Boolean search terms, the search strategy combined synonyms of 'fracture' and 'DPP-4 inhibitor'. Comprehensive electronic databases which include EMBASE, MEDLINE, the EMA and the WHO ICTRP databases were searched for randomised controlled trial (RCT) studies which compared a DPP-4 inhibitor with an active comparator or placebo amongst patients with T2DM. Meta-analysis was performed to compare DPP-4 inhibitor with either an active comparator or a placebo. The outcome measure was the presence or absence of fracture. The search yielded 5061 records relating to fractures and DPP-4 inhibitor, from which 51 eligible RCTs were selected for meta-analysis (N=36,402). Thirty-seven (37) studies compared DPP-4 inhibitor with placebo (n=23,974), while fourteen (14) studies (n=12,428) compared DPP-4 inhibitor with an active comparator. The mean age of patients was 57.5±5.4years, the average glycated haemoglobin (HbA1c) was 8.2%, while the average BMI was 30±2kg/m(2). Overall, there was no significant association of fracture events with the use of DPP-4 inhibitor when compared with placebo (OR; 0.82, 95% CI 0.57-1.16, P=0.9) or when DPP-4 inhibitor was compared against an active comparator (OR; 1.59, 95% CI 0.91-2.80, P=0.9). This study offers a larger, up-to-date review of the subject. The meta-analysis showed that there was no significant association between DPP-4 inhibitor use and the incidence of fractures. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genetic ablation or pharmacological blockade of dipeptidyl peptidase IV does not impact T cell-dependent immune responses

PubMed Central

Vora, Kalpit A; Porter, Gene; Peng, Roche; Cui, Yan; Pryor, Kellyann; Eiermann, George; Zaller, Dennis M

2009-01-01

Background Current literature suggests that dipeptidyl peptidase IV (DPP-IV; CD26) plays an essential role in T-dependent immune responses, a role that could have important clinical consequences. To rigorously define the role of DPP-IV in the immune system, we evaluated genetic and pharmacological inhibition of the enzyme on T-dependent immune responses in vivo. Results The DPP-IV null animals mounted robust primary and secondary antibody responses to the T dependent antigens, 4-hydroxy-3-nitrophenylacetyl-ovalbumin (NP-Ova) and 4-hydroxy-3-nitrophenylacetyl-chicken gamma globulin (NP-CGG), which were comparable to wild type mice. Serum levels of antigen specific IgM, IgG1, IgG2a, IgG2b and IgG3 were similar between the two groups of animals. DPP-IV null animals mounted an efficient germinal center reaction by day 10 after antigen stimulation that was comparable to wild type mice. Moreover, the antibodies produced by DPP-IV null animals after repeated antigenic challenge were affinity matured. Similar observations were made using wild type animals treated with a highly selective DPP-IV inhibitor during the entire course of the experiments. T cell recall responses to ovalbumin and MOG peptide, evaluated by measuring proliferation and IL-2 release from cells isolated from draining lymph nodes, were equivalent in DPP-IV null and wild type animals. Furthermore, mice treated with DPP-IV inhibitor had intact T-cell recall responses to MOG peptide. In addition, female DPP-IV null and wild type mice treated with DPP-IV inhibitor exhibited normal and robust in vivo cytotoxic T cell responses after challenge with cells expressing the male H-Y minor histocompatibility antigen. Conclusion These data indicate Selective inhibition of DPP-IV does not impair T dependent immune responses to antigenic challenge. PMID:19358731

Glucose-independent renoprotective mechanisms of the tissue dipeptidyl peptidase-4 inhibitor, saxagliptin, in Dahl salt-sensitive hypertensive rats.

PubMed

Uchii, Masako; Kimoto, Naoya; Sakai, Mariko; Kitayama, Tetsuya; Kunori, Shunji

2016-07-15

Although previous studies have shown an important role of renal dipeptidyl peptidase-4 (DPP-4) inhibition in ameliorating kidney injury in hypertensive rats, the renal distribution of DPP-4 and mechanisms of renoprotective action of DPP-4 inhibition remain unclear. In this study, we examined the effects of the DPP-4 inhibitor saxagliptin on DPP-4 activity in renal cells (using in situ DPP-4 staining) and on renal gene expression related to inflammation and fibrosis in the renal injury in hypertensive Dahl salt-sensitive (Dahl-S) rats. Male rats fed a high-salt (8% NaCl) diet received vehicle (water) or saxagliptin (12.7mg/kg/day) for 4 weeks. Blood pressure (BP), serum glucose and 24-h urinary albumin and sodium excretions were measured, and renal histopathology was performed. High salt-diet increased BP and urinary albumin excretion, consequently resulting in glomerular sclerosis and tubulointerstitial fibrosis. Although saxagliptin did not affect BP and blood glucose levels, it significantly ameliorated urinary albumin excretion. In situ staining showed DPP-4 activity in glomerular and tubular cells. Saxagliptin significantly suppressed DPP-4 activity in renal tissue extracts and in glomerular and tubular cells. Saxagliptin also significantly attenuated the increase in inflammation and fibrosis-related gene expressions in the kidney. Our results demonstrate that saxagliptin inhibited the development of renal injury independent of its glucose-lowering effect. Glomerular and tubular DPP-4 inhibition by saxagliptin was associated with improvements in albuminuria and the suppression of inflammation and fibrosis-related genes. Thus, local glomerular and tubular DPP-4 inhibition by saxagliptin may play an important role in its renoprotective effects in Dahl-S rats. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Asp- and Glu-specific Novel Dipeptidyl Peptidase 11 of Porphyromonas gingivalis Ensures Utilization of Proteinaceous Energy Sources*

PubMed Central

Ohara-Nemoto, Yuko; Shimoyama, Yu; Kimura, Shigenobu; Kon, Asako; Haraga, Hiroshi; Ono, Toshio; Nemoto, Takayuki K.

2011-01-01

Porphyromonas gingivalis and Porphyromonas endodontalis, asaccharolytic black-pigmented anaerobes, are predominant pathogens of human chronic and periapical periodontitis, respectively. They incorporate di- and tripeptides from the environment as carbon and energy sources. In the present study we cloned a novel dipeptidyl peptidase (DPP) gene of P. endodontalis ATCC 35406, designated as DPP11. The DPP11 gene encoded 717 amino acids with a molecular mass of 81,090 Da and was present as a 75-kDa form with an N terminus of Asp22. A homology search revealed the presence of a P. gingivalis orthologue, PGN0607, that has been categorized as an isoform of authentic DPP7. P. gingivalis DPP11 was exclusively cell-associated as a truncated 60-kDa form, and the gene ablation retarded cell growth. DPP11 specifically removed dipeptides from oligopeptides with the penultimate N-terminal Asp and Glu and has a P2-position preference to hydrophobic residues. Optimum pH was 7.0, and the kcat/Km value was higher for Asp than Glu. Those activities were lost by substitution of Ser652 in P. endodontalis and Ser655 in P. gingivalis DPP11 to Ala, and they were consistently decreased with increasing NaCl concentration. Arg670 is a unique amino acid completely conserved in all DPP11 members distributed in the genera Porphyromonas, Bacteroides, and Parabacteroides, whereas this residue is converted to Gly in all authentic DPP7 members. Substitution analysis suggested that Arg670 interacts with an acidic residue of the substrate. Considered to preferentially utilize acidic amino acids, DPP11 ensures efficient degradation of oligopeptide substrates in these Gram-negative anaerobic rods. PMID:21896480

Wingless, decapentaplegic and EGF receptor signaling pathways interact to specify dorso-ventral pattern in the adult abdomen of Drosophila.

PubMed

Kopp, A; Blackman, R K; Duncan, I

1999-08-01

Adult abdominal segments of Drosophila are subdivided along the dorso-ventral axis into a dorsal tergite, a ventral sternite and ventro-lateral pleural cuticle. We report that this pattern is largely specified during the pupal stage by Wingless (Wg), Decapentaplegic (Dpp) and Drosophila EGF Receptor (DER) signaling. Expression of wg and dpp is activated at the posterior edge of the anterior compartment by Hedgehog signaling. Within this region, wg and dpp are expressed in domains that are mutually exclusive along the dorso-ventral axis: wg is expressed in the sternite and medio-lateral tergite, whereas dpp expression is confined to the pleura and the dorsal midline. Neither gene is expressed in the lateral tergite. Shirras and Couso (1996, Dev. Biol. 175, 24-36) have shown that tergite and sternite cell fates are specified by Wg signaling. We find that DER acts synergistically with Wg to promote tergite and sternite identities, and that Wg and DER activities are opposed by Dpp signaling, which promotes pleural identity. Wg and Dpp interact antagonistically at two levels. First, their expression is confined to complementary domains by mutual transcriptional repression. Second, Wg and Dpp compete directly with one another by exerting opposite effects on cell fate. DER signaling does not affect the expression of wg or dpp, indicating that it interacts with Wg and Dpp at the level of cell fate determination. Within the tergite, the requirements for Wg and DER function are roughly complementary: Wg is required mainly in the medial region, whereas DER is most important laterally. Finally, we show that Dpp signaling at the dorsal midline controls dorso-ventral patterning within the tergite by promoting pigmentation in the medial region.

Cut to the chase: a review of CD26/dipeptidyl peptidase‐4's (DPP4) entanglement in the immune system

PubMed Central

Wagner, L.; Stephan, M.; von Hörsten, S.

2016-01-01

Summary CD26/DPP4 (dipeptidyl peptidase 4/DP4/DPPIV) is a surface T cell activation antigen and has been shown to have DPP4 enzymatic activity, cleaving‐off amino‐terminal dipeptides with either L‐proline or L‐alanine at the penultimate position. It plays a major role in glucose metabolism by N‐terminal truncation and inactivation of the incretins glucagon‐like peptide‐1 (GLP) and gastric inhibitory protein (GIP). In 2006, DPP4 inhibitors have been introduced to clinics and have been demonstrated to efficiently enhance the endogenous insulin secretion via prolongation of the half‐life of GLP‐1 and GIP in patients. However, a large number of studies demonstrate clearly that CD26/DPP4 also plays an integral role in the immune system, particularly in T cell activation. Therefore, inhibition of DPP4 might represent a double‐edged sword. Apart from the metabolic benefit, the associated immunological effects of long term DPP4 inhibition on regulatory processes such as T cell homeostasis, maturation and activation are not understood fully at this stage. The current data point to an important role for CD26/DPP4 in maintaining lymphocyte composition and function, T cell activation and co‐stimulation, memory T cell generation and thymic emigration patterns during immune‐senescence. In rodents, critical immune changes occur at baseline levels as well as after in‐vitro and in‐vivo challenge. In patients receiving DPP4 inhibitors, evidence of immunological side effects also became apparent. The scope of this review is to recapitulate the role of CD26/DPP4 in the immune system regarding its pharmacological inhibition and T cell‐dependent immune regulation. PMID:26919392

Asp- and Glu-specific novel dipeptidyl peptidase 11 of Porphyromonas gingivalis ensures utilization of proteinaceous energy sources.

PubMed

Ohara-Nemoto, Yuko; Shimoyama, Yu; Kimura, Shigenobu; Kon, Asako; Haraga, Hiroshi; Ono, Toshio; Nemoto, Takayuki K

2011-11-04

Porphyromonas gingivalis and Porphyromonas endodontalis, asaccharolytic black-pigmented anaerobes, are predominant pathogens of human chronic and periapical periodontitis, respectively. They incorporate di- and tripeptides from the environment as carbon and energy sources. In the present study we cloned a novel dipeptidyl peptidase (DPP) gene of P. endodontalis ATCC 35406, designated as DPP11. The DPP11 gene encoded 717 amino acids with a molecular mass of 81,090 Da and was present as a 75-kDa form with an N terminus of Asp(22). A homology search revealed the presence of a P. gingivalis orthologue, PGN0607, that has been categorized as an isoform of authentic DPP7. P. gingivalis DPP11 was exclusively cell-associated as a truncated 60-kDa form, and the gene ablation retarded cell growth. DPP11 specifically removed dipeptides from oligopeptides with the penultimate N-terminal Asp and Glu and has a P2-position preference to hydrophobic residues. Optimum pH was 7.0, and the k(cat)/K(m) value was higher for Asp than Glu. Those activities were lost by substitution of Ser(652) in P. endodontalis and Ser(655) in P. gingivalis DPP11 to Ala, and they were consistently decreased with increasing NaCl concentration. Arg(670) is a unique amino acid completely conserved in all DPP11 members distributed in the genera Porphyromonas, Bacteroides, and Parabacteroides, whereas this residue is converted to Gly in all authentic DPP7 members. Substitution analysis suggested that Arg(670) interacts with an acidic residue of the substrate. Considered to preferentially utilize acidic amino acids, DPP11 ensures efficient degradation of oligopeptide substrates in these Gram-negative anaerobic rods.

Structure activity relationship modelling of milk protein-derived peptides with dipeptidyl peptidase IV (DPP-IV) inhibitory activity.

PubMed

Nongonierma, Alice B; FitzGerald, Richard J

2016-05-01

Quantitative structure activity type models were developed in an attempt to predict the key features of peptide sequences having dipeptidyl peptidase IV (DPP-IV) inhibitory activity. The models were then employed to help predict the potential of peptides, which are currently reported in the literature to be present in the intestinal tract of humans following milk/dairy product ingestion, to act as inhibitors of DPP-IV. Two models (z- and v-scale) for short (2-5 amino acid residues) bovine milk peptides, behaving as competitive inhibitors of DPP-IV, were developed. The z- and the v-scale models (p<0.05, R(2) of 0.829 and 0.815, respectively) were then applied to 56 milk protein-derived peptides previously reported in the literature to be found in the intestinal tract of humans which possessed a structural feature of DPP-IV inhibitory peptides (P at the N2 position). Ten of these peptides were synthetized and tested for their in vitro DPP-IV inhibitory properties. There was no agreement between the predicted and experimentally determined DPP-IV half maximal inhibitory concentrations (IC50) for the competitive peptide inhibitors. However, the ranking for DPP-IV inhibitory potency of the competitive peptide inhibitors was conserved. Furthermore, potent in vitro DPP-IV inhibitory activity was observed with two peptides, LPVPQ (IC50=43.8±8.8μM) and IPM (IC50=69.5±8.7μM). Peptides present within the gastrointestinal tract of human may have promise for the development of natural DPP-IV inhibitors for the management of serum glucose. Copyright © 2016 Elsevier Inc. All rights reserved.

Cardiac DPP-4 inhibition by saxagliptin ameliorates isoproterenol-induced myocardial remodeling and cardiac diastolic dysfunction in rats.

PubMed

Ikeda, Junichi; Kimoto, Naoya; Kitayama, Tetsuya; Kunori, Shunji

2016-09-01

Saxagliptin, a potent and selective DPP-4 inhibitor, is characterized by its slow dissociation from DPP-4 and its long half-life and is expected to have a potent tissue membrane-bound DPP-4-inhibitory effect in various tissues. In the present study, we examined the effects of saxagliptin on in situ cardiac DPP-4 activity. We also examined the effects of saxagliptin on isoproterenol-induced the changes in the early stage such as, myocardial remodeling and cardiac diastolic dysfunction. Male SD rats treated with isoproterenol (1 mg/kg/day via osmotic pump) received vehicle or saxagliptin (17.5 mg/kg via drinking water) for 2 weeks. In situ cardiac DPP-4 activity was measured by a colorimetric assay. Cardiac gene expressions were examined and an echocardiographic analysis was performed. Saxagliptin treatment significantly inhibited in situ cardiac DPP-4 activity and suppressed isoproterenol-induced myocardial remodeling and the expression of related genes without altering the blood glucose levels. Saxagliptin also significantly ameliorated cardiac diastolic dysfunction in isoproterenol-treated rats. In conclusion, the inhibition of DPP-4 activity in cardiac tissue by saxagliptin was associated with suppression of myocardial remodeling and cardiac diastolic dysfunction independently of its glucose-lowering action in isoproterenol-treated rats. Cardiac DPP-4 activity may contribute to myocardial remodeling in the development of heart failure. Copyright © 2016 Kyowa Hakko Kirin Co.,Ltd. Production and hosting by Elsevier B.V. All rights reserved.

Dipeptidyl Peptidase 10 (DPP10789): A Voltage Gated Potassium Channel Associated Protein Is Abnormally Expressed in Alzheimer's and Other Neurodegenerative Diseases

PubMed Central

Gai, Wei-Ping; Abbott, Catherine A.

2014-01-01

The neuropathological features associated with Alzheimer's disease (AD) include the presence of extracellular amyloid-β peptide-containing plaques and intracellular tau positive neurofibrillary tangles and the loss of synapses and neurons in defined regions of the brain. Dipeptidyl peptidase 10 (DPP10) is a protein that facilitates Kv4 channel surface expression and neuronal excitability. This study aims to explore DPP10789 protein distribution in human brains and its contribution to the neurofibrillary pathology of AD and other tauopathies. Immunohistochemical analysis revealed predominant neuronal staining of DPP10789 in control brains, and the CA1 region of the hippocampus contained strong reactivity in the distal dendrites of the pyramidal cells. In AD brains, robust DPP10789 reactivity was detected in neurofibrillary tangles and plaque-associated dystrophic neurites, most of which colocalized with the doubly phosphorylated Ser-202/Thr-205 tau epitope. DPP10789 positive neurofibrillary tangles and plaque-associated dystrophic neurites also appeared in other neurodegenerative diseases such as frontotemporal lobar degeneration, diffuse Lewy body disease, and progressive supranuclear palsy. Occasional DPP10789 positive neurofibrillary tangles and neurites were seen in some aged control brains. Western blot analysis showed both full length and truncated DPP10789 fragments with the later increasing significantly in AD brains compared to control brains. Our results suggest that DPP10789 is involved in the pathology of AD and other neurodegenerative diseases. PMID:25025038

Bi-diketopyrrolopyrrole (Bi-DPP) as a novel electron accepting compound in low band gap π-conjugated donor–acceptor copolymers/oligomers

PubMed Central

Ahner, Johannes; Nowotny, Jürgen; Schubert, Ulrich S.; Hager, Martin D.

2017-01-01

Abstract The synthesis and characterization of a novel 2,5-diketopyrrolo[3,4-c]pyrrole(DPP)-based accepting building block with the scheme DPP-neutral small linker-DPP (Bi-DPP) is presented, which was utilized as electron accepting moiety for low band gap π-conjugated donor–acceptor copolymers as well as for a donor–acceptor small molecule. The electron accepting moiety Bi-DPP was prepared via a novel synthetic pathway by building up two DPP moieties step by step simultaneously starting from a neutral phenyl core unit. Characterization of the synthesized oligomeric and polymeric materials via cyclic voltammetry afford LUMO energy levels from −3.49 to −3.59 eV as well as HOMO energy levels from −5.07 to −5.34 eV resulting in low energy band gaps from 1.52 to 1.81 eV. Spin coating of the prepared donor–acceptor oligomers/polymers resulted in well-defined films. Moreover, UV–vis measurements of the investigated donor–acceptor systems showed a broad absorption over the whole visible region. It is demonstrated that Bi-DPP as an electron accepting moiety in donor–acceptor systems offer potential properties for organic solar cell devices. PMID:29491794

EFFECTS OF SOG ON DPP-RECEPTOR BINDING*

PubMed Central

LOU, YUAN; NIE, QING; WAN, FREDERIC Y. M.

2007-01-01

Concentration gradients of morphogens are known to be instrumental in cell signaling and tissue patterning. Of interest here is how the presence of a competitor of BMP ligands affects cell signaling. The effects of Sog on the binding of Dpp with cell receptors are analyzed for dorsal-ventral morphogen gradient formation in vertebrate and Drosophila embryos. This prototype system includes diffusing ligands, degradation of morphogens, and cleavage of Dpp-Sog complexes by Tolloid to free up Dpp. Simple and biologically meaningful necessary and sufficient conditions for the existence of a steady state gradient configuration are established, and existence theorems are proved. For high Sog production rates (relative to the Dpp production rate), it is found that the steady state configuration exhibits a more intense Dpp-receptor concentration near the dorsal midline. Numerical simulations of the evolution of the system show that, beyond some threshold Sog production rate, the transient Dpp-receptor concentration at the dorsal midline would become more intense than that of the steady state, before subsiding and approaching a nonuniform steady state of lower magnitude. The magnitude of the transient concentration has been found to increase by several fold with increasing Sog production rate. The highly intense Dpp activity at and around the dorsal midline is consistent with available experimental observations and other analytical studies. PMID:17377624

The Influence of Fluorination on Nano-Scale Phase Separation and Photovoltaic Performance of Small Molecular/PC71BM Blends

PubMed Central

Lu, Zhen; Liu, Wen; Li, Jingjing; Fang, Tao; Li, Wanning; Zhang, Jicheng; Feng, Feng; Li, Wenhua

2016-01-01

To investigate the fluorination influence on the photovoltaic performance of small molecular based organic solar cells (OSCs), six small molecules based on 2,1,3-benzothiadiazole (BT), and diketopyrrolopyrrole (DPP) as core and fluorinated phenyl (DFP) and triphenyl amine (TPA) as different terminal units (DFP-BT-DFP, DFP-BT-TPA, TPA-BT-TPA, DFP-DPP-DFP, DFP-DPP-TPA, and TPA-DPP-TPA) were synthesized. With one or two fluorinated phenyl as the end group(s), HOMO level of BT and DPP based small molecular donors were gradually decreased, inducing high open circuit voltage for fluorinated phenyl based OSCs. DFP-BT-TPA and DFP-DPP-TPA based blend films both displayed stronger nano-scale aggregation in comparison to TPA-BT-TPA and TPA-DPP-TPA, respectively, which would also lead to higher hole motilities in devices. Ultimately, improved power conversion efficiency (PCE) of 2.17% and 1.22% was acquired for DFP-BT-TPA and DFP-DPP-TPA based devices, respectively. These results demonstrated that the nano-scale aggregation size of small molecules in photovoltaic devices could be significantly enhanced by introducing a fluorine atom at the donor unit of small molecules, which will provide understanding about the relationship of chemical structure and nano-scale phase separation in OSCs. PMID:28335208

The Role of Date Palm (Phoenix dactylifera L) Pollen in Fertility: A Comprehensive Review of Current Evidence.

PubMed

Tahvilzadeh, Mohammad; Hajimahmoodi, Mannan; Rahimi, Roja

2016-10-01

Date palm pollen (DPP) is the male reproductive dust of palm flowers used as dietary supplement especially as aphrodisiac and fertility enhancer in both women and men from ancient times. Although there are few clinical trials evaluating the beneficial effects of DPP in humans, various experimental studies have been conducted on the reproductive effects of DPP. Among the compounds isolated from DPP are amino acids, fatty acids, flavonoids, saponins, and estroles. The present review summarizes comprehensive information concerning the phytochemistry and pharmacological activities of DPP and its application in fertility disorders. © The Author(s) 2015.

Plasma 25-hydroxyvitamin D and progression to diabetes in patients at risk for diabetes: an ancillary analysis in the diabetes prevention program

USDA-ARS?s Scientific Manuscript database

We investigated the association between vitamin D status, assessed by plasma 25-hydroxyvitamin D, and risk of incident diabetes. The research design and methods were a prospective observational study with a mean follow-up of 2.7 years in the Diabetes Prevention Program (DPP), a multi-center trial co...

Cost effectiveness of dipeptidyl peptidase-4 inhibitors for type 2 diabetes.

PubMed

Geng, Jinsong; Yu, Hao; Mao, Yiwei; Zhang, Peng; Chen, Yingyao

2015-06-01

Dipeptidyl peptidase-4 (DPP-4) inhibitors are a new class of antidiabetic drugs used for treating type 2 diabetes mellitus. While many studies have reported on the cost-effectiveness of DPP-4 inhibitors for treating type 2 diabetes, a systematic review of economic evaluations of DPP-4 inhibitors is currently lacking. The aim of this systematic review was to assess the cost effectiveness of DPP-4 inhibitors for patients with type 2 diabetes. MEDLINE, EMBASE, National Health Service Economic Evaluation Database (NHS EED), Web of Science, EconLit databases, and the Cochrane Library were searched in November 2013. Studies assessing the cost effectiveness of DPP-4 inhibitors for type 2 diabetes were eligible for analysis. DPP-4 inhibitor monotherapy or combinations with other antidiabetic agents were included in the review. The DPP-4 inhibitors were all marketed drugs. Two reviewers independently reviewed titles, abstracts, and articles sequentially to select studies for data abstraction based on the inclusion and exclusion criteria. Disagreements were resolved by consensus. The quality of included studies was assessed according to the 24-item checklist of the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement. The costs reported by the included studies were converted to US dollars via purchasing power parities (PPP) in the year 2013 using the CCEMG-EPPI-Center Cost Converter. A total of 11 published studies were selected for inclusion; all were cost-utility analyses. Nine studies were conducted from a payer perspective and one used a societal perspective; however, the perspective of the other study was unclear. Four studies were of good quality, six were of moderate quality, and one was of low quality. Of the seven studies comparing DPP-4 inhibitors plus metformin with sulfonylureas plus metformin, six concluded that DPP-4 inhibitors were cost effective in patients with type 2 diabetes who were no longer adequately controlled by metformin monotherapy. Five studies compared DPP-4 inhibitors with thiazolidinediones, and whether DPP-4 inhibitors were cost effective was uncertain. Only two economic evaluations provided data to compare DPP-4 inhibitors versus insulin, and the results favored the use of DPP-4 inhibitors as second-line therapy. Synthesis of the data was impossible because of heterogeneity in the methodology and data sources of the economic evaluations, and the inclusion criteria excluded conference abstracts. It was difficult to find reliable weightings for each of the items of the CHEERS checklist, and the ratings were dichotomous. This study provides the first systematic evaluation of DPP-4 inhibitors for patients with type 2 diabetes. It found that, in patients with type 2 diabetes who do not achieve glycemic targets with antidiabetic monotherapy, DPP-4 inhibitors as add-on treatment may represent a cost-effective option compared with sulfonylureas and insulin. However, high-quality cost-effectiveness analyses that utilize long-term follow-up data and have no conflicts of interest are still needed.

Design and Elaboration of a Tractable Tricyclic Scaffold To Synthesize Druglike Inhibitors of Dipeptidyl Peptidase-4 (DPP-4), Antagonists of the C-C Chemokine Receptor Type 5 (CCR5), and Highly Potent and Selective Phosphoinositol-3 Kinase δ (PI3Kδ) Inhibitors.

PubMed

Schwehm, Carolin; Kellam, Barrie; Garces, Aimie E; Hill, Stephen J; Kindon, Nicholas D; Bradshaw, Tracey D; Li, Jin; Macdonald, Simon J F; Rowedder, James E; Stoddart, Leigh A; Stocks, Michael J

2017-02-23

A novel molecular scaffold has been synthesized, and its incorporation into new analogues of biologically active molecules across multiple target classes will be discussed. In these studies, we have shown use of the tricyclic scaffold to synthesize potent inhibitors of the serine peptidase DPP-4, antagonists of the CCR5 receptor, and highly potent and selective PI3K δ isoform inhibitors. We also describe the predicted physicochemical properties of the resulting inhibitors and conclude that the tractable molecular scaffold could have potential application in future drug discovery programs.

The 24-month metabolic benefits of the healthy living partnerships to prevent diabetes: A community-based translational study.

PubMed

Pedley, Carolyn F; Case, L Douglas; Blackwell, Caroline S; Katula, Jeffrey A; Vitolins, Mara Z

2018-05-01

Large-scale clinical trials and translational studies have demonstrated that weight loss achieved through diet and physical activity reduced the development of diabetes in overweight individuals with prediabetes. These interventions also reduced the occurrence of metabolic syndrome and risk factors linked to other chronic conditions including obesity-driven cancers and cardiovascular disease. The Healthy Living Partnerships to Prevent Diabetes (HELP PD) was a clinical trial in which participants were randomized to receive a community-based lifestyle intervention translated from the Diabetes Prevention Program (DPP) or an enhanced usual care condition. The objective of this study is to compare the 12 and 24 month prevalence of metabolic syndrome in the two treatment arms of HELP PD. The intervention involved a group-based, behavioral weight-loss program led by community health workers monitored by personnel from a local diabetes education program. The enhanced usual care condition included dietary counseling and written materials. HELP PD included 301 overweight or obese participants (BMI 25-39.9kg/m 2 ) with elevated fasting glucose levels (95-125mg/dl). At 12 and 24 months of follow-up there were significant improvements in individual components of the metabolic syndrome: fasting blood glucose, waist circumference, HDL, triglycerides and blood pressure and the occurrence of the metabolic syndrome in the intervention group compared to the usual care group. This study demonstrates that a community diabetes prevention program in participants with prediabetes results in metabolic benefits and a reduction in the occurrence of the metabolic syndrome in the intervention group compared to the enhanced usual care group. Copyright © 2017 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Diketopyrrolopyrrole-based carbon dots for photodynamic therapy.

PubMed

He, Haozhe; Zheng, Xiaohua; Liu, Shi; Zheng, Min; Xie, Zhigang; Wang, Yong; Yu, Meng; Shuai, Xintao

2018-06-01

The development of a simple and straightforward strategy to synthesize multifunctional carbon dots for photodynamic therapy (PDT) has been an emerging focus. In this work, diketopyrrolopyrrole-based fluorescent carbon dots (DPP CDs) were designed and synthesized through a facile one-pot hydrothermal method by using diketopyrrolopyrrole (DPP) and chitosan (CTS) as raw materials. DPP CDs not only maintained the ability of DPP to generate singlet oxygen (1O2) but also have excellent hydrophilic properties and outstanding biocompatibility. In vitro and in vivo experiments demonstrated that DPP CDs greatly inhibited the growth of tumor cells under laser irradiation (540 nm). This study highlights the potential of the rational design of CDs for efficient cancer therapy.

Discovery of Novel Tricyclic Heterocycles as Potent and Selective DPP-4 Inhibitors for the Treatment of Type 2 Diabetes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Wen-Lian; Hao, Jinsong; Domalski, Martin

In our efforts to develop second generation DPP-4 inhibitors, we endeavored to identify distinct structures with long-acting (once weekly) potential. Taking advantage of X-ray cocrystal structures of sitagliptin and other DPP-4 inhibitors, such as alogliptin and linagliptin bound to DPP-4, and aided by molecular modeling, we designed several series of heterocyclic compounds as initial targets. During their synthesis, an unexpected chemical transformation provided a novel tricyclic scaffold that was beyond our original design. Capitalizing on this serendipitous discovery, we have elaborated this scaffold into a very potent and selective DPP-4 inhibitor lead series, as highlighted by compound 17c.

Drosophila bunched integrates opposing DPP and EGF signals to set the operculum boundary.

PubMed

Dobens, L L; Peterson, J S; Treisman, J; Raftery, L A

2000-02-01

The Drosophila BMP homolog DPP can function as a morphogen, inducing multiple cell fates across a developmental field. However, it is unknown how graded levels of extracellular DPP are interpreted to organize a sharp boundary between different fates. Here we show that opposing DPP and EGF signals set the boundary for an ovarian follicle cell fate. First, DPP regulates gene expression in the follicle cells that will create the operculum of the eggshell. DPP induces expression of the enhancer trap reporter A359 and represses expression of bunched, which encodes a protein similar to the mammalian transcription factor TSC-22. Second, DPP signaling indirectly regulates A359 expression in these cells by downregulating expression of bunched. Reduced bunched function restores A359 expression in cells that lack the Smad protein MAD; ectopic expression of BUNCHED suppresses A359 expression in this region. Importantly, reduction of bunched function leads to an expansion of the operculum and loss of the collar at its boundary. Third, EGF signaling upregulates expression of bunched. We previously demonstrated that the bunched expression pattern requires the EGF receptor ligand GURKEN. Here we show that activated EGF receptor is sufficient to induce ectopic bunched expression. Thus, the balance of DPP and EGF signals sets the boundary of bunched expression. We propose that the juxtaposition of cells with high and low BUNCHED activity organizes a sharp boundary for the operculum fate.

Modulation of substance P signaling by dipeptidyl peptidase-IV enzymatic activity in human glioma cell lines.

PubMed

Busek, P; Stremenová, J; Krepela, E; Sedo, A

2008-01-01

Dipeptidyl peptidase-IV (DPP-IV, CD26) is a serine protease almost ubiquitously expressed on cell surface and present in body fluids. DPP-IV has been suggested to proteolytically modify a number of biologically active peptides including substance P (SP) and the chemokine stromal cell derived factor-1alpha (SDF-1alpha, CXCL12). SP and SDF-1alpha have been implicated in the regulation of multiple biological processes and also induce responses that may be relevant for glioma progression. Both SP and SDF-1alpha are signaling through cell surface receptors and use intracellular calcium as a second messenger. The effect of DPP-IV on intracellular calcium mobilization mediated by SP and SDF-1alpha was monitored in suspension of wild type U373 and DPP-IV transfected U373DPPIV glioma cells using indicator FURA-2. Nanomolar concentrations of SP triggered a transient dose dependent increase in intracellular calcium rendering the cells refractory to repeated stimulation, while SDF-1 had no measurable effect. SP signaling in DPP-IV overexpressing U373DPPIV cells was not substantially different from that in wild type cells. However, preincubation of SP with the DPP-IV overexpressing cells lead to the loss of its signaling potential, which could be prevented with DPP-IV inhibitors. Taken together, DPP-IV may proteolytically inactivate local mediators involved in gliomagenesis.

Mutant HNF-1{alpha} and mutant HNF-1{beta} identified in MODY3 and MODY5 downregulate DPP-IV gene expression in Caco-2 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gu Ning; Laboratory of Neurochemistry, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto; Adachi, Tetsuya

2006-08-04

Dipeptidylpeptidase IV (DPP-IV) is a well-documented drug target for the treatment of type 2 diabetes. Hepatocyte nuclear factors (HNF)-1{alpha} and HNF-1{beta}, known as the causal genes of MODY3 and MODY5, respectively, have been reported to be involved in regulation of DPP-IV gene expression. But, it is not completely clear (i) that they play roles in regulation of DPP-IV gene expression, and (ii) whether DPP-IV gene activity is changed by mutant HNF-1{alpha} and mutant HNF-1{beta} in MODY3 and MODY5. To explore these questions, we investigated transactivation effects of wild HNF-1{alpha} and 13 mutant HNF-1{alpha}, as well as wild HNF-1{beta} and 2more » mutant HNF-1{beta}, on DPP-IV promoter luciferase gene in Caco-2 cells by means of a transient experiment. Both wild HNF-1{alpha} and wild HNF-1{beta} significantly transactivated DPP-IV promoter, but mutant HNF-1{alpha} and mutant HNF-1{beta} exhibited low transactivation activity. Moreover, to study whether mutant HNF-1{alpha} and mutant HNF-1{beta} change endogenous DPP-IV enzyme activity, we produced four stable cell lines from Caco-2 cells, in which wild HNF-1{alpha} or wild HNF-1{beta}, or else respective dominant-negative mutant HNF-1{alpha}T539fsdelC or dominant-negative mutant HNF-1{beta}R177X, was stably expressed. We found that DPP-IV gene expression and enzyme activity were significantly increased in wild HNF-1{alpha} cells and wild HNF-1{beta} cells, whereas they decreased in HNF-1{alpha}T539fsdelC cells and HNF-1{beta}R177X cells, compared with DPP-IV gene expression and enzyme activity in Caco-2 cells. These results suggest that both wild HNF-1{alpha} and wild HNF-1{beta} have a stimulatory effect on DPP-IV gene expression, but that mutant HNF-1{alpha} and mutant HNF-1{beta} attenuate the stimulatory effect.« less

Dipeptidyl peptidase-4 inhibitors-associated bullous pemphigoid: a retrospective study of 168 pemphigoid and 9,304 diabetes mellitus cases.

PubMed

Kawaguchi, Yohei; Shimauchi, Risa; Nishibori, Nobuhiro; Kawashima, Kiyohito; Oshitani, So; Fujiya, Atsushi; Shibata, Taiga; Ohashi, Norimi; Izumi, Kentaro; Nishie, Wataru; Shimizu, Hiroshi; Arima, Hiroshi; Sobajima, Hiroshi

2018-06-19

Bullous pemphigoid (BP) may be drug-induced. This study evaluated the relation between BP and dipeptidyl peptidase-4 inhibitors (DPP4Is). We recruited patients diagnosed with BP at Ogaki Municipal Hospital from December 1, 2009 through December 31, 2017. We retrospectively collected data from medical records and divided patients into two groups based on whether they received DPP4Is. Additionally, we determined the incidence of BP in patients who were first prescribed DPP4Is at our hospital during the study period. Of 168 patients diagnosed with BP, 133 (79.1%) were positive for anti-BP180NC16a antibody. Thirty-two (19.0%) patients had been prescribed a DPP4I, 21 of whom (65.6%) were positive for anti-BP180NC16a antibody; this rate was lower than that in patients not receiving a DPP4I (82.3%) (p = 0.0360). Sixteen patients with type 2 diabetes mellitus (T2DM) had not been prescribed a DPP4I; only one (6.3%) was positive for anti-BP180NC16a antibody (p = 0.0339). During the study period, 9304 patients were prescribed DPP4Is, eight of whom developed BP; six (75.0%) had non-inflammatory BP, and five of the six (83.3%) were negative for anti-BP180NC16a antibody. The positive rate of anti-BP180NC16a antibody was lower in BP patients with DPP4I than without DPP4I, regardless of T2DM. The antibody titer was low in both the overall and T2DM populations. The prevalence of BP in 9304 patients receiving DPP4Is was 0.0859%, which is higher than that in the general population. Since DPP4Is are common diabetes treatments, we must be aware of the risk of BP. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

S-glutathionylation of an auxiliary subunit confers redox sensitivity to Kv4 channel inactivation.

PubMed

Jerng, Henry H; Pfaffinger, Paul J

2014-01-01

Reactive oxygen species (ROS) regulate ion channels, modulate neuronal excitability, and contribute to the etiology of neurodegenerative disorders. ROS differentially suppress fast "ball-and-chain" N-type inactivation of cloned Kv1 and Kv3 potassium channels but not of Kv4 channels, likely due to a lack of reactive cysteines in Kv4 N-termini. Recently, we discovered that N-type inactivation of Kv4 channel complexes can be independently conferred by certain N-terminal variants of Kv4 auxiliary subunits (DPP6a, DPP10a). Here, we report that both DPP6a and DPP10a, like Kv subunits with redox-sensitive N-type inactivation, contain a highly conserved cysteine in their N-termini (Cys-13). To test if N-type inactivation mediated by DPP6a or DPP10a is redox sensitive, Xenopus oocyte recordings were performed to examine the effects of two common oxidants, tert-butyl hydroperoxide (tBHP) and diamide. Both oxidants markedly modulate DPP6a- or DPP10a-conferred N-type inactivation of Kv4 channels, slowing the overall inactivation and increasing the peak current. These functional effects are fully reversed by the reducing agent dithiothreitol (DTT) and appear to be due to a selective modulation of the N-type inactivation mediated by these auxiliary subunits. Mutation of DPP6a Cys-13 to serine eliminated the tBHP or diamide effects, confirming the importance of Cys-13 to the oxidative regulation. Biochemical studies designed to elucidate the underlying molecular mechanism show no evidence of protein-protein disulfide linkage formation following cysteine oxidation. Instead, using a biotinylated glutathione (BioGEE) reagent, we discovered that oxidation by tBHP or diamide leads to S-glutathionylation of Cys-13, suggesting that S-glutathionylation underlies the regulation of fast N-type inactivation by redox. In conclusion, our studies suggest that Kv4-based A-type current in neurons may show differential redox sensitivity depending on whether DPP6a or DPP10a is highly expressed, and that the S-glutathionylation mechanism may play a previously unappreciated role in mediating excitability changes and neuropathologies associated with ROS.

Self-determination theory and weight loss in a Diabetes Prevention Program translation trial.

PubMed

Trief, Paula M; Cibula, Donald; Delahanty, Linda M; Weinstock, Ruth S

2017-06-01

We examined self-determination theory (SDT) and weight loss, and hypothesized that the Diabetes Prevention Program's (DPP) intervention would result in an increase in autonomous regulation of motivation (AR) in participants. Further, that those with higher AR, and those who perceived educators as supporting SDT-defined needs, would lose more weight. Support, Health Information, Nutrition and Exercise (SHINE) Study data (N = 257) were analyzed. SHINE was a randomized, controlled DPP translation trial (2-years, telephonic, primary care staff). Autonomous motivation in males increased significantly, while females showed no change. Males with high AR, but not females, lost more weight. However, the significance of these relationships varied over time. Participants who perceived educators as more supportive of psychological needs lost more weight (especially males). However, effect of support on weight loss was not mediated by AR change. Autonomous motivation and educator support are relevant to male weight loss. Future research might develop interventions to enhance autonomous motivation and educator support, and understand change pathways.

Head-to-head comparison of structurally unrelated dipeptidyl peptidase 4 inhibitors in the setting of renal ischemia reperfusion injury.

PubMed

Reichetzeder, Christoph; von Websky, Karoline; Tsuprykov, Oleg; Mohagheghi Samarin, Azadeh; Falke, Luise Gabriele; Dwi Putra, Sulistyo Emantoko; Hasan, Ahmed Abdallah; Antonenko, Viktoriia; Curato, Caterina; Rippmann, Jörg; Klein, Thomas; Hocher, Berthold

2017-07-01

Results regarding protective effects of dipeptidyl peptidase 4 (DPP4) inhibitors in renal ischaemia-reperfusion injury (IRI) are conflicting. Here we have compared structurally unrelated DPP4 inhibitors in a model of renal IRI. IRI was induced in uninephrectomized male rats by renal artery clamping for 30 min. The sham group was uninephrectomized but not subjected to IRI. DPP4 inhibitors or vehicle were given p.o. once daily on three consecutive days prior to IRI: linagliptin (1.5 mg·kg -1 ·day -1 ), vildagliptin (8 mg·kg -1 ·day -1 ) and sitagliptin (30 mg·kg -1 ·day -1 ). An additional group received sitagliptin until study end (before IRI: 30 mg·kg -1 ·day -1 ; after IRI: 15 mg·kg -1 ·day -1 ). Plasma-active glucagon-like peptide type 1 (GLP-1) increased threefold to fourfold in all DPP4 inhibitor groups 24 h after IRI. Plasma cystatin C, a marker of GFR, peaked 48 h after IRI. Compared with the placebo group, DPP4 inhibition did not reduce increased plasma cystatin C levels. DPP4 inhibitors ameliorated histopathologically assessed tubular damage with varying degrees of drug-specific efficacies. Renal osteopontin expression was uniformly reduced by all DPP4 inhibitors. IRI-related increased renal cytokine expression was not decreased by DPP4 inhibition. Renal DPP4 activity at study end was significantly inhibited in the linagliptin group, but only numerically reduced in the prolonged/dose-adjusted sitagliptin group. Active GLP-1 plasma levels at study end were increased only in the prolonged/dose-adjusted sitagliptin treatment group. In rats with renal IRI, DPP4 inhibition did not alter plasma cystatin C, a marker of glomerular function, but may protect against tubular damage. © 2017 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

Identification of Novel Human Dipeptidyl Peptidase-IV Inhibitors of Natural Origin (Part II): In Silico Prediction in Antidiabetic Extracts

PubMed Central

Guasch, Laura; Sala, Esther; Ojeda, María José; Valls, Cristina; Bladé, Cinta; Mulero, Miquel; Blay, Mayte; Ardévol, Anna; Garcia-Vallvé, Santiago; Pujadas, Gerard

2012-01-01

Background Natural extracts play an important role in traditional medicines for the treatment of diabetes mellitus and are also an essential resource for new drug discovery. Dipeptidyl peptidase IV (DPP-IV) inhibitors are potential candidates for the treatment of type 2 diabetes mellitus, and the effectiveness of certain antidiabetic extracts of natural origin could be, at least partially, explained by the inhibition of DPP-IV. Methodology/Principal Findings Using an initial set of 29,779 natural products that are annotated with their natural source and an experimentally validated virtual screening procedure previously developed in our lab (Guasch et al.; 2012) [1], we have predicted 12 potential DPP-IV inhibitors from 12 different plant extracts that are known to have antidiabetic activity. Seven of these molecules are identical or similar to molecules with described antidiabetic activity (although their role as DPP-IV inhibitors has not been suggested as an explanation for their bioactivity). Therefore, it is plausible that these 12 molecules could be responsible, at least in part, for the antidiabetic activity of these extracts through their inhibitory effect on DPP-IV. In addition, we also identified as potential DPP-IV inhibitors 6 molecules from 6 different plants with no described antidiabetic activity but that share the same genus as plants with known antidiabetic properties. Moreover, none of the 18 molecules that we predicted as DPP-IV inhibitors exhibits chemical similarity with a group of 2,342 known DPP-IV inhibitors. Conclusions/Significance Our study identified 18 potential DPP-IV inhibitors in 18 different plant extracts (12 of these plants have known antidiabetic properties, whereas, for the remaining 6, antidiabetic activity has been reported for other plant species from the same genus). Moreover, none of the 18 molecules exhibits chemical similarity with a large group of known DPP-IV inhibitors. PMID:23028712

Dipeptidyl peptidase-4 inhibitor ameliorates early renal injury through its anti-inflammatory action in a rat model of type 1 diabetes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kodera, Ryo, E-mail: kodera@cc.okayama-u.ac.jp; Shikata, Kenichi; Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558

Highlights: •DPP-4 inhibitor decreased urinary albumin excretion in a rat of type 1 diabetes. •DPP-4 inhibitor ameliorated histlogical changes of diabetic nephropathy. •DPP-4 inhibitor has reno-protective effects through anti-inflammatory action. •DPP-4 inhibitor is beneficial on diabetic nephropathy besides lowering blood glucose. -- Abstract: Introduction: Dipeptidyl peptidase-4 (DPP-4) inhibitors are incretin-based drugs in patients with type 2 diabetes. In our previous study, we showed that glucagon-like peptide-1 (GLP-1) receptor agonist has reno-protective effects through anti-inflammatory action. The mechanism of action of DPP-4 inhibitor is different from that of GLP-1 receptor agonists. It is not obvious whether DPP-4 inhibitor prevents the exacerbationmore » of diabetic nephropathy through anti-inflammatory effects besides lowering blood glucose or not. The purpose of this study is to clarify the reno-protective effects of DPP-4 inhibitor through anti-inflammatory actions in the early diabetic nephropathy. Materials and methods: Five-week-old male Sprague–Dawley (SD) rats were divided into three groups; non-diabetes, diabetes and diabetes treated with DPP-4 inhibitor (PKF275-055; 3 mg/kg/day). PKF275-055 was administered orally for 8 weeks. Results: PKF275-055 increased the serum active GLP-1 concentration and the production of urinary cyclic AMP. PKF275-055 decreased urinary albumin excretion and ameliorated histological change of diabetic nephropathy. Macrophage infiltration was inhibited, and inflammatory molecules were down-regulated by PKF275-055 in the glomeruli. In addition, nuclear factor-κB (NF-κB) activity was suppressed in the kidney. Conclusions: These results indicate that DPP-4 inhibitor, PKF275-055, have reno-protective effects through anti-inflammatory action in the early stage of diabetic nephropathy. The endogenous biological active GLP-1 might be beneficial on diabetic nephropathy besides lowering blood glucose.« less

Histoplasma capsulatum encodes a dipeptidyl peptidase active against the mammalian immunoregulatory peptide, substance P.

PubMed

Cooper, Kendal G; Zarnowski, Robert; Woods, Jon P

2009-01-01

The pathogenic fungus Histoplasma capsulatum secretes dipeptidyl peptidase (Dpp) IV enzyme activity and has two putative DPPIV homologs (HcDPPIVA and HcDPPIVB). We previously showed that HcDPPIVB is the gene responsible for the majority of secreted DppIV activity in H. capsulatum culture supernatant, while we could not detect any functional contribution from HcDPPIVA. In order to determine whether HcDPPIVA encodes a functional DppIV enzyme, we expressed HcDPPIVA in Pichia pastoris and purified the recombinant protein. The recombinant enzyme cleaved synthetic DppIV substrates and had similar biochemical properties to other described DppIV enzymes, with temperature and pH optima of 42 degrees C and 8, respectively. Recombinant HcDppIVA cleaved the host immunoregulatory peptide substance P, indicating the enzyme has the potential to affect the immune response during infection. Expression of HcDPPIVA under heterologous regulatory sequences in H. capsulatum resulted in increased secreted DppIV activity, indicating that the encoded protein can be expressed and secreted by its native organism. However, HcDPPIVA was not required for virulence in a murine model of histoplasmosis. This work reports a fungal enzyme that can function to cleave the immunomodulatory host peptide substance P.

Probing charge transfer complex states in organic solar cells using photocurrent spectroscopy

NASA Astrophysics Data System (ADS)

Moghe, Dhanashree; Adil, Danish; Kanimozhi, Catherine; Dutta, Gitesh; Patil, Satish; Guha, Suchismita

2013-03-01

Diketopyrrolopyrrole (DPP) containing copolymers-fullerene blends have gained a lot of interest in organic optoelectronics with a great potential in organic photovoltaics (OPVs). The interfacial charge transfer complex (CTC) states formed in donor-acceptor blended OPVs play a major role in the overall efficiency of the device. We investigate the spectral photocurrent characteristics of five DPP based copolymers; two of them being benzothiadiazole and carbazole -based statistical copolymers of DPP. These systems provide a wide range of bandgap energies ranging from ~ 1.4 to 1.7 eV. We use Fourier transform photocurrent spectroscopy (FTPS) and monochromatic photocurrent (PC) to identify the CTC states in these DPP copolymer -fullerene blends. The stability of the CTC state is found to be dependent on the band gap energy difference between the donor copolymer and the acceptor. We support our inferences from theoretical results obtained using density-functional theory (DFT) and time-dependent DFT for two DPP based copolymers The theoretical calculations reveal a higher contribution of the CTC states to the lowest excited state in the phenyl-based DPP monomer, which has a larger bandgap energy compared to the thiophene-based DPP system, in the presence of a fullerene molecule.

Quantitative structure-activity relationships (QSAR) of some 2,2-diphenyl propionate (DPP) derivatives of muscarinic antagonists

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gordon, R.K.; Breuer, E.; Padilla, F.N.

1987-05-01

QSAR between biological activities and molecular-chemical properties were investigated to aid in designing more effective and potent antimuscarinic pharmacophores. A molecular modeling program was used to calculate geometrical and topological values of a series of DPP pharmacophores. The newly synthesized pharmacophores were tested for their antagonist activities by: (1) inhibition of (N-methyl-/sup 3/H)scopolamine binding assay to the muscarinic receptors of N4TG1 neuroblastoma cells; (2) blocking of acetylcholine-induced contraction of guinea pig ileum; and (3) inhibition of carbachol-induced ..cap alpha..-amylase release from rat pancreas. The differences in the log of these biological activities were directly and significantly related to the distancesmore » between the carbonyl oxygen of the DPP and the quaternary nitrogen of the modified pharmacophores. The biological activities, while depending on each particular assay, varied between three and four logs of activity. The charge remained the same in all the pharmacophores. There were no QSAR correlations between molecular volume, molecular connectivity, or principle moments and their antagonistic activities, although multivariate QSAR was not employed. Thus, based on distance geometry, potent muscarinic pharmacophores can be predicted.« less

Critical role of renal dipeptidyl peptidase-4 in ameliorating kidney injury induced by saxagliptin in Dahl salt-sensitive hypertensive rats.

PubMed

Sakai, Mariko; Uchii, Masako; Myojo, Kensuke; Kitayama, Tetsuya; Kunori, Shunji

2015-08-15

Saxagliptin, a potent dipeptidyl peptidase-4 (DPP-4) inhibitor, is currently used to treat type 2 diabetes mellitus, and it has been reported to exhibit a slower rate of dissociation from DPP-4 compared with another DPP-4 inhibitor, sitagliptin. In this study, we compared the effects of saxagliptin and sitagliptin on hypertension-related renal injury and the plasma and renal DPP-4 activity levels in Dahl salt-sensitive hypertensive (Dahl-S) rats. The high-salt diet (8% NaCl) significantly increased the blood pressure and quantity of urinary albumin excretion and induced renal glomerular injury in the Dahl-S rats. Treatment with saxagliptin (14mg/kg/day via drinking water) for 4 weeks significantly suppressed the increase in urinary albumin excretion and tended to ameliorate glomerular injury without altering the blood glucose levels and systolic blood pressure. On the other hand, the administration of sitagliptin (140mg/kg/day via drinking water) did not affect urinary albumin excretion and glomerular injury in the Dahl-S rats. Meanwhile, the high-salt diet increased the renal DPP-4 activity but did not affect the plasma DPP-4 activity in the Dahl-S rats. Both saxagliptin and sitagliptin suppressed the plasma DPP-4 activity by 95% or more. Although the renal DPP-4 activity was also inhibited by both drugs, the inhibitory effect of saxagliptin was more potent than that of sitagliptin. These results indicate that saxagliptin has a potent renoprotective effect in the Dahl-S rats, independent of its glucose-lowering actions. The inhibition of the renal DPP-4 activity induced by saxagliptin may contribute to ameliorating renal injury in hypertension-related renal injury. Copyright © 2015 Elsevier B.V. All rights reserved.

Involvement of DPP-IV catalytic residues in enzyme–saxagliptin complex formation

PubMed Central

Metzler, William J.; Yanchunas, Joseph; Weigelt, Carolyn; Kish, Kevin; Klei, Herbert E.; Xie, Dianlin; Zhang, Yaqun; Corbett, Martin; Tamura, James K.; He, Bin; Hamann, Lawrence G.; Kirby, Mark S.; Marcinkeviciene, Jovita

2008-01-01

The inhibition of DPP-IV by saxagliptin has been proposed to occur through formation of a covalent but reversible complex. To evaluate further the mechanism of inhibition, we determined the X-ray crystal structure of the DPP-IV:saxagliptin complex. This structure reveals covalent attachment between S630 and the inhibitor nitrile carbon (C–O distance <1.3 Å). To investigate whether this serine addition is assisted by the catalytic His-Asp dyad, we generated two mutants of DPP-IV, S630A and H740Q, and assayed them for ability to bind inhibitor. DPP-IVH740Q bound saxagliptin with an ∼1000-fold reduction in affinity relative to DPP-IVWT, while DPP-IVS630A showed no evidence for binding inhibitor. An analog of saxagliptin lacking the nitrile group showed unchanged binding properties to the both mutant proteins, highlighting the essential role S630 and H740 play in covalent bond formation between S630 and saxagliptin. Further supporting mechanism-based inhibition by saxagliptin, NMR spectra of enzyme–saxagliptin complexes revealed the presence of three downfield resonances with low fractionation factors characteristic of short and strong hydrogen bonds (SSHB). Comparison of the NMR spectra of various wild-type and mutant DPP-IV:ligand complexes enabled assignment of a resonance at ∼14 ppm to H740. Two additional DPP-IV mutants, Y547F and Y547Q, generated to probe potential stabilization of the enzyme–inhibitor complex by this residue, did not show any differences in inhibitor binding either by ITC or NMR. Together with the previously published enzymatic data, the structural and binding data presented here strongly support a histidine-assisted covalent bond formation between S630 hydroxyl oxygen and the nitrile group of saxagliptin. PMID:18227430

Involvement of DPP-IV Catalytic Residues in Enzyme-Saxagliptin Complex Formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Metzler,W.; Yanchunas, J.; Weigelt, C.

The inhibition of DPP-IV by saxagliptin has been proposed to occur through formation of a covalent but reversible complex. To evaluate further the mechanism of inhibition, we determined the X-ray crystal structure of the DPP-IV:saxagliptin complex. This structure reveals covalent attachment between S630 and the inhibitor nitrile carbon (C-O distance <1.3 Angstroms). To investigate whether this serine addition is assisted by the catalytic His-Asp dyad, we generated two mutants of DPP-IV, S630A and H740Q, and assayed them for ability to bind inhibitor. DPP-IVH740Q bound saxagliptin with an {approx}1000-fold reduction in affinity relative to DPP-IVWT, while DPP-IVS630A showed no evidence formore » binding inhibitor. An analog of saxagliptin lacking the nitrile group showed unchanged binding properties to the both mutant proteins, highlighting the essential role S630 and H740 play in covalent bond formation between S630 and saxagliptin. Further supporting mechanism-based inhibition by saxagliptin, NMR spectra of enzyme-saxagliptin complexes revealed the presence of three downfield resonances with low fractionation factors characteristic of short and strong hydrogen bonds (SSHB). Comparison of the NMR spectra of various wild-type and mutant DPP-IV:ligand complexes enabled assignment of a resonance at {approx}14 ppm to H740. Two additional DPP-IV mutants, Y547F and Y547Q, generated to probe potential stabilization of the enzyme-inhibitor complex by this residue, did not show any differences in inhibitor binding either by ITC or NMR. Together with the previously published enzymatic data, the structural and binding data presented here strongly support a histidine-assisted covalent bond formation between S630 hydroxyl oxygen and the nitrile group of saxagliptin.« less

Effects of Crystal Morphology on Singlet Exciton Fission in Diketopyrrolopyrrole Thin Films.

PubMed

Hartnett, Patrick E; Margulies, Eric A; Mauck, Catherine M; Miller, Stephen A; Wu, Yilei; Wu, Yi-Lin; Marks, Tobin J; Wasielewski, Michael R

2016-02-25

Singlet exciton fission (SF) is a promising strategy for increasing photovoltaic efficiency, but in order for SF to be useful in solar cells, it should take place in a chromophore that is air-stable, highly absorptive, solution processable, and inexpensive. Unlike many SF chromophores, diketopyrrolopyrrole (DPP) conforms to these criteria, and here we investigate SF in DPP for the first time. SF yields in thin films of DPP derivatives, which are widely used in organic electronics and photovoltaics, are shown to depend critically on crystal morphology. Time-resolved spectroscopy of three DPP derivatives with phenyl (3,6-diphenylpyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione, PhDPP), thienyl (3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione, TDPP), and phenylthienyl (3,6-di(5-phenylthiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione, PhTDPP) aromatic substituents in 100-200 nm thin films reveals that efficient SF occurs only in TDPP and PhTDPP (τSF = 220 ± 20 ps), despite the fact that SF is most exoergic in PhDPP. This result correlates well with the greater degree of π-overlap and closer π-stacking in TDPP (3.50 Å) and PhTDPP (3.59 Å) relative to PhDPP (3.90 Å) and demonstrates that SF in DPP is highly sensitive to the electronic coupling between adjacent chromophores. The triplet yield in PhTDPP films is determined to be 210 ± 35% by the singlet depletion method and 165 ± 30% by the energy transfer method, showing that SF is nearly quantitative in these films and that DPP derivatives are a promising class of SF chromophores for enhancing photovoltaic performance.

Hepatic Dipeptidyl Peptidase-4 Controls Pharmacokinetics of Vildagliptin In Vivo.

PubMed

Asakura, Mitsutoshi; Fukami, Tatsuki; Nakajima, Miki; Fujii, Hideaki; Atsuda, Koichiro; Itoh, Tomoo; Fujiwara, Ryoichi

2017-02-01

The main route of elimination of vildagliptin, which is an inhibitor of dipeptidyl peptidase-4 (DPP-4), in humans is cyano group hydrolysis to produce a carboxylic acid metabolite M20.7. Our in vitro study previously demonstrated that DPP-4 itself greatly contributed to the hydrolysis of vildagliptin in mouse, rat, and human livers. To investigate whether hepatic DPP-4 contributes to the hydrolysis of vildagliptin in vivo, in the present study, we conducted in vivo pharmacokinetics studies of vildagliptin in mice coadministered with vildagliptin and sitagliptin, which is another DPP-4 inhibitor, and also in streptozotocin (STZ)-induced diabetic mice. The area under the plasma concentration-time curve (AUC) value of M20.7 in mice coadministered with vildagliptin and sitagliptin was significantly lower than that in mice administered vildagliptin alone (P < 0.01). Although plasma DPP-4 expression level was increased 1.9-fold, hepatic DPP-4 activity was decreased in STZ-induced diabetic mice. The AUC values of M20.7 in STZ-induced diabetic mice were lower than those in control mice (P < 0.01). Additionally, the AUC values of M20.7 significantly positively correlated with hepatic DPP-4 activities in the individual mice (Rs = 0.943, P < 0.05). These findings indicated that DPP-4 greatly contributed to the hydrolysis of vildagliptin in vivo and that not plasma, but hepatic DPP-4 controlled pharmacokinetics of vildagliptin. Furthermore, enzyme assays of 23 individual human liver samples showed that there was a 3.6-fold interindividual variability in vildagliptin-hydrolyzing activities. Predetermination of the interindividual variability of hepatic vildagliptin-hydrolyzing activity might be useful for the prediction of blood vildagliptin concentrations in vivo. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Regulation of Dpp activity by tissue-specific cleavage of an upstream site within the prodomain

PubMed Central

Sopory, Shailaja; Kwon, Sunjong; Wehrli, Marcel; Christian, Jan L.

2010-01-01

BMP4 is synthesized as an inactive precursor that is cleaved at two sites during maturation: initially at a site (S1) adjacent to the ligand domain, and then at an upstream site (S2) within the prodomain. Cleavage at the second site regulates the stability of mature BMP4 and this in turn influences its signaling intensity and range of action. The Drosophila ortholog of BMP4, Dpp, functions as a long- or short-range signaling molecule in the wing disc or embryonic midgut, respectively but mechanisms that differentially regulate its bioactivity in these tissues have not been explored. In the current studies we demonstrate, by dpp mutant rescue, that cleavage at the S2 site of proDpp is required for development of the wing and leg imaginal discs, whereas cleavage at the S1 site is sufficient to rescue Dpp function in the midgut. Both the S1 and S2 site of proDpp are cleaved in the wing disc, and S2-cleavage is essential to generate sufficient ligand to exceed the threshold for pMAD activation at both short- and long-range in most cells. By contrast, proDpp is cleaved at the S1 site alone in the embryonic mesoderm and this generates sufficient ligand to activate physiological target genes in neighboring cells. These studies provide the first biochemical and genetic evidence that that selective cleavage of the S2 site of proDPP provides a tissue-specific mechanism for regulating Dpp activity, and that differential cleavage can contribute to, but is not an absolute determinant of signaling range. PMID:20659445

Transcriptomic and metabolomic analyses of cucumber fruit peels reveal a developmental increase in terpenoid glycosides associated with age-related resistance to Phytophthora capsici

PubMed Central

Mansfeld, Ben N; Colle, Marivi; Kang, Yunyan; Jones, A Daniel; Grumet, Rebecca

2017-01-01

The oomycete, Phytophthora capsici, infects cucumber (Cucumis sativus L.) fruit. An age-related resistance (ARR) to this pathogen was previously observed in fruit of cultivar ‘Vlaspik’ and shown to be associated with the peel. Young fruits are highly susceptible, but develop resistance at ~10–12 days post pollination (dpp). Peels from resistant (16 dpp) versus susceptible (8 dpp) age fruit are enriched with genes associated with defense, and methanolic extracts from resistant age peels inhibit pathogen growth. Here we compared developing fruits from ‘Vlaspik’ with those of ‘Gy14’, a line that does not exhibit ARR. Transcriptomic analysis of peels of the two lines at 8 and 16 dpp identified 80 genes that were developmentally upregulated in resistant ‘Vlaspik’ 16 dpp versus 8 dpp, but not in susceptible ‘Gy14’ at 16 dpp. A large number of these genes are annotated to be associated with defense and/or specialized metabolism, including four putative resistance (R) genes, and numerous genes involved in flavonoid and terpenoid synthesis and decoration. Untargeted metabolomic analysis was performed on extracts from 8 and 16 dpp ‘Vlaspik’ and ‘Gy14’ fruit peels using Ultra-Performance Liquid Chromatography and Quadrupole Time-of-Flight Mass Spectrometry. Multivariate analysis of the metabolomes identified 113 ions uniquely abundant in resistant ‘Vlaspik’ 16 dpp peel extracts. The most abundant compounds in this group had relative mass defects consistent with terpenoid glycosides. Two of the three most abundant ions were annotated as glycosylated nor-terpenoid esters. Together, these analyses reveal potential mechanisms by which ARR to P. capsici may be conferred. PMID:28580151

Effects of linagliptin on human immortalized podocytes: a cellular system to study dipeptidyl‐peptidase 4 inhibition

PubMed Central

Miglio, Gianluca; Vitarelli, Giovanna; Klein, Thomas

2017-01-01

Background and Purpose Dipeptidyl‐peptidase 4 (DPP4) is expressed by resident renal cells, including glomerular cells. DPP4 inhibitors (gliptins) exert albuminuria lowering effects, but the role of renal DPP4 as a pharmacological target has not been elucidated. To better understand the actions of gliptins, the effects of linagliptin on the behaviour of immortalized human podocytes and mesangial cells were evaluated. Experimental Approach The expression of DPP4 was measured at both the mRNA and protein levels. The effects of linagliptin on DPP4 activity, cell growth and cell cycle progression were determined. The contribution of the stromal cell‐derived factor‐1‐ CXCR4/CXCR7 signalling pathways was evaluated by studying the effects of AMD3100 (a CXCR4 antagonist and CXCR7 agonist) alone and in combination with linagliptin. The contribution of ERK1/2 activation was analysed by studying the effects of the MAPK kinase 1/2 inhibitor AZD6244. Key Results DPP4 was highly expressed in podocytes. The activity of DPP4 and podocyte growth were reduced by linagliptin. The effects of sitagliptin on podocyte growth were similar to those of linagliptin, were associated with inhibition of cell proliferation and mimicked by AMD3100. Moreover, linagliptin and AMD3100 were found to have a synergistic interaction, whereas no interaction was seen between linagliptin and AZD6244. Conclusions and Implications Our cultures of human glomerular cells represent a reliable system for investigating the actions of gliptins. Moreover, DPP4 contributes to the regulation of podocyte behaviour. Inhibition of DPP4 in podocytes could underlie the effects of linagliptin on glomerular cells. PMID:28177527

Comparative short-term inhalation toxicity of five organic diketopyrrolopyrrole pigments and two inorganic iron-oxide-based pigments

PubMed Central

Hofmann, Thomas; Ma-Hock, Lan; Strauss, Volker; Treumann, Silke; Rey Moreno, Maria; Neubauer, Nicole; Wohlleben, Wendel; Gröters, Sibylle; Wiench, Karin; Veith, Ulrich; Teubner, Wera; van Ravenzwaay, Bennard; Landsiedel, Robert

2016-01-01

Abstract Diketopyrrolopyrroles (DPP) are a relatively new class of organic high-performance pigments. The present inhalation and particle characterization studies were performed to compare the effects of five DPP-based pigments (coarse and fine Pigment Red 254, coarse and fine meta-chloro DPP isomer and one form of mixed chlorinated DPP isomers) and compare it to coarse and fine inorganic Pigment Red 101. Wistar rats were exposed head-nose to atmospheres of the respective materials for 6 h/day on 5 consecutive days. Target concentrations were 30 mg/m3 as high dose for all compounds and selected based occupational exposure limits for respirable nuisance dust. Toxicity was determined after end of exposure and after 3-week recovery using broncho-alveolar lavage fluid (BALF) and microscopic examinations of the entire respiratory tract. Mixed chlorinated DPP isomers and coarse meta-chloro DPP isomer caused marginal changes in BALF, consisting of slight increases of polymorphonuclear neutrophils, and in case of coarse meta-chloro DPP increased MCP-1 and osteopontin levels. Mixed chlorinated DPP isomers, Pigment Red 254, and meta-chloro DPP caused pigment deposits and phagocytosis by alveolar macrophages, slight hypertrophy/hyperplasia of the bronchioles and alveolar ducts, but without evidence of inflammation. In contrast, only pigment deposition and pigment phagocytosis were observed after exposure to Pigment Red 101. All pigments were tolerated well and caused only marginal effects in BALF or no effects at all. Only minor effects were seen on the lung by microscopic examination. There was no evidence of systemic inflammation based on acute-phase protein levels in blood. PMID:27387137

In silico approaches to predict the potential of milk protein-derived peptides as dipeptidyl peptidase IV (DPP-IV) inhibitors.

PubMed

Nongonierma, Alice B; Mooney, Catherine; Shields, Denis C; FitzGerald, Richard J

2014-07-01

Molecular docking of a library of all 8000 possible tripeptides to the active site of DPP-IV was used to determine their binding potential. A number of tripeptides were selected for experimental testing, however, there was no direct correlation between the Vina score and their in vitro DPP-IV inhibitory properties. While Trp-Trp-Trp, the peptide with the best docking score, was a moderate DPP-IV inhibitor (IC50 216μM), Lineweaver and Burk analysis revealed its action to be non-competitive. This suggested that it may not bind to the active site of DPP-IV as assumed in the docking prediction. Furthermore, there was no significant link between DPP-IV inhibition and the physicochemical properties of the peptides (molecular mass, hydrophobicity, hydrophobic moment (μH), isoelectric point (pI) and charge). LIGPLOTs indicated that competitive inhibitory peptides were predicted to have both hydrophobic and hydrogen bond interactions with the active site of DPP-IV. DPP-IV inhibitory peptides generally had a hydrophobic or aromatic amino acid at the N-terminus, preferentially a Trp for non-competitive inhibitors and a broader range of residues for competitive inhibitors (Ile, Leu, Val, Phe, Trp or Tyr). Two of the potent DPP-IV inhibitors, Ile-Pro-Ile and Trp-Pro (IC50 values of 3.5 and 44.2μM, respectively), were predicted to be gastrointestinally/intestinally stable. This work highlights the needs to test the assumptions (i.e. competitive binding) of any integrated strategy of computational and experimental screening, in optimizing screening. Future strategies targeting allosteric mechanisms may need to rely more on structure-activity relationship modeling, rather than on docking, in computationally selecting peptides for screening. Copyright © 2014 Elsevier Inc. All rights reserved.

Design, synthesis and biological evaluation of novel pyrazolo-pyrimidinones as DPP-IV inhibitors in diabetes.

PubMed

Sagar, Sneha R; Agarwal, Jessica K; Pandya, Dhaivat H; Dash, Ranjeet Prasad; Nivsarkar, Manish; Vasu, Kamala K

2015-10-15

We report the design, synthesis, biological activity and docking studies of series of novel pyrazolo[3,4-d]pyrimidinones as DPP-IV inhibitors in diabetes. Molecules were synthesized and evaluated for their DPP-IV inhibition activity. Compounds 5e, 5k, 5o and 6a were found to be potent inhibitors of DPP-IV enzyme. Amongst all the synthesized compounds, 6-methyl-5-(4-methylpyridin-2-yl)-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-one (5k) was found to be the most active based on in vitro DPP-IV studies and also exhibited promising in vivo blood glucose lowering activity in male Wistar rats. Copyright © 2015. Published by Elsevier Ltd.

Cytoneme-mediated contact-dependent transport of the Drosophila decapentaplegic signaling protein.

PubMed

Roy, Sougata; Huang, Hai; Liu, Songmei; Kornberg, Thomas B

2014-02-21

Decapentaplegic (Dpp), a Drosophila morphogen signaling protein, transfers directly at synapses made at sites of contact between cells that produce Dpp and cytonemes that extend from recipient cells. The Dpp that cytonemes receive moves together with activated receptors toward the recipient cell body in motile puncta. Genetic loss-of-function conditions for diaphanous, shibire, neuroglian, and capricious perturbed cytonemes by reducing their number or only the synapses they make with cells they target, and reduced cytoneme-mediated transport of Dpp and Dpp signaling. These experiments provide direct evidence that cells use cytonemes to exchange signaling proteins, that cytoneme-based exchange is essential for signaling and normal development, and that morphogen distribution and signaling can be contact-dependent, requiring cytoneme synapses.

Cytoneme-mediated contact-dependent transport of the Drosophila Decapentaplegic signaling protein

PubMed Central

Roy, Sougata; Huang, Hai; Liu, Songmei; Kornberg, Thomas B.

2015-01-01

Decapentaplegic (Dpp), a Drosophila morphogen signaling protein, transfers directly at synapes made at sites of contact between cells that produce Dpp and cytonemes that extend from recipient cells. The Dpp that cytonemes receive moves together with activated receptors toward the recipient cell body in motile puncta. Genetic loss-of-function conditions for diaphanous, shibire, neuroglian and capricious perturbed cytonemes by reducing their number or only the synapses they make with cells they target; and reduced cytoneme-mediated transport of Dpp and Dpp signaling. These experiments provide direct evidence that cells use cytonemes to exchange signaling proteins, that cytoneme-based exchange is essential for signaling and normal development, and that morphogen distribution and signaling can be contact-dependent, requiring cytoneme synapses. PMID:24385607

A New Approach to Study Properties of Isolated Predipocytes Following In Vivo Exposure to Hypoxia

NASA Astrophysics Data System (ADS)

Chowdhury, Helena H.; Velebit Markovic, Jelena; Radic, Natasa; Francic, Vito; Mekjavic, Igor B.; Eiken, Ola; Zorec, Robert

2013-02-01

In the present study we developed a novel approach to study the properties of isolated human preadipocytes from subjects exposed to conditions of hypoxia equivalent to an altitude of 4000 m. By using confocal microscopy we studied the expression of dipeptidyl peptidase 4 (DPP4) in preadipocytes from adult normal-weight males. DPP4 is a transmembrane glycoprotein with enzymatic activity that cleaves N-terminal dipeptides from a diverse range of substrates. The activity of DPP4 is implicated in immune response as well as in glucose homeostasis. To gain insights into the pathophysiological role of DPP4 in insulin resistance we here explored DPP4 expression during prolonged exposure to hypoxia, an experimental model of obesity onset. We used here a rapid method to isolate cells from biopsies and immunolabelled them with antibodies. Then cells were prepared for the analysis with confocal microscopy. The results show that a prolonged exposure to hypoxic environment appears to increases the expression of DPP4 on preadipocytes.

Safety, effectiveness, and cost of dipeptidyl peptidase-4 inhibitors versus intermediate acting insulin for type 2 diabetes: protocol for a systematic review and network meta-analysis.

PubMed

Tricco, Andrea C; Antony, Jesmin; Soobiah, Charlene; Hemmelgarn, Brenda; Moher, David; Hutton, Brian; Yu, Catherine H; Majumdar, Sumit R; Straus, Sharon E

2013-06-28

Type 2 diabetes mellitus (T2DM) results from insulin resistance and relative insulin deficiency. T2DM treatment is a step-wise approach beginning with lifestyle modifications (for example, diet, exercise), followed by the addition of oral hypoglycemic agents (for example, metformin). Patients who do not respond to first-line therapy are offered second-line therapy (for example, sulfonylureas). Third-line therapy may include insulin and/or dipeptidyl peptidase-4 (DPP-4) inhibitors.It is unclear whether DPP-4 inhibitors are safer and more effective than intermediate acting insulin for third-line management of T2DM. As such, our objective is to evaluate the comparative effectiveness, safety and cost-effectiveness of DPP-4 inhibitors versus intermediate acting insulin for T2DM patients who have failed both first- and second-line diabetes treatments. Electronic searches of MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, and grey literature (for example, trial registries, public health websites) will be conducted to identify studies examining DPP-4 inhibitors compared with each other, intermediate acting insulin, no treatment, or placebo for adults with T2DM. The outcomes of interest include glycosylated hemoglobin (A1C) (primary outcome), as well as emergency department visits, physician visits, hospital admissions, weight gain, quality of life, microvascular complications, macrovascular complications, all-cause mortality, and cost (secondary outcomes). Randomized clinical trials (RCTs), quasi-RCTs, non-RCTs, controlled before-after, interrupted time series, cohort studies, and cost studies reporting data on these outcomes will be included. Eligibility will not be restricted by publication status, language of dissemination, duration of study follow-up, or time period of study conduct.Two reviewers will screen the titles and abstracts resulting from the literature search, as well as potentially relevant full-text articles, in duplicate. Data will be abstracted and quality will be appraised by two team members independently. Conflicts at all levels of screening and abstraction will be resolved through team discussion.Our results will be described narratively. Random effects meta-analysis and network meta-analysis will be conducted, if feasible and appropriate. Our systematic review results can be used to determine the most effective, safe and cost-effective third-line strategies for managing T2DM. This information will be of great use to health policy-makers and clinicians, as well as patients living with T2DM and their families. PROSPERO registry number: CRD42013003624.

A mobile phone-based program to promote healthy behaviors among adults with prediabetes: study protocol for a pilot randomized controlled trial.

PubMed

Griauzde, Dina H; Kullgren, Jeffrey T; Liestenfeltz, Brad; Richardson, Caroline; Heisler, Michele

2018-01-01

Rates of participation in Diabetes Prevention Programs (DPPs) are low. This may be due, in part, to low levels of autonomous motivation (i.e., motivation that arises from internal sources and sustains healthy behaviors over time) to prevent type 2 diabetes (T2DM) among many individuals with prediabetes. Mobile health (mHealth) technologies that incorporate principles from the Self-Determination Theory offer an effective and scalable approach to increase autonomous motivation levels. One promising mobile phone-based application is JOOL Health, which aims to help users connect certain health behaviors (e.g., sleep and diet) with personal values in specific life domains (e.g., family and work). The first aim of this study is to estimate whether JOOL Health can increase autonomous motivation to prevent T2DM among individuals with prediabetes who declined DPP participation. The second aim of this pilot study is to examine the intervention's feasibility and acceptability. This is a 12-week, three-arm pilot randomized controlled trial. We will recruit 105 individuals with prediabetes who did not engage in a DPP despite invitation from their health plan to participate in face-to-face or web-based programs at no out-of-pocket-cost. Participants will be randomized to one of three study arms: (1) a group that receives information on prediabetes, evidence-based strategies to decrease progression to T2DM, and a list of resources for mHealth tools for monitoring diet, physical activity, and weight (comparison group); (2) a group that receives the JOOL Health application; and (3) a group that receives the JOOL Health application as well as a Fitbit activity tracker and wireless-enabled scale. Our primary outcome is change in autonomous motivation to prevent T2DM (measured using the Treatment Self-Regulation Questionnaire). We will also collect data related to the intervention's feasibility (recruitment and retention rates) and acceptability (adherence and qualitative experience) as well as changes in psychosocial outcomes, hemoglobin A1c, and weight. To our knowledge, this is the first study that aims to promote positive health behaviors among individuals with prediabetes who previously declined to participate in a DPP. Our results will inform a larger trial to test the effect of JOOL Health on clinically relevant outcomes, including weight loss, physical activity, and DPP engagement. NCT03025607. Registered February 2017.

E3024, 3-but-2-ynyl-5-methyl-2-piperazin-1-yl-3,5-dihydro-4H-imidazo[4,5-d]pyridazin-4-one tosylate, is a novel, selective and competitive dipeptidyl peptidase-IV inhibitor.

PubMed

Yasuda, Nobuyuki; Nagakura, Tadashi; Inoue, Takashi; Yamazaki, Kazuto; Katsutani, Naruo; Takenaka, Osamu; Clark, Richard; Matsuura, Fumiyoshi; Emori, Eita; Yoshikawa, Seiji; Kira, Kazunobu; Ikuta, Hironori; Okada, Toshimi; Saeki, Takao; Asano, Osamu; Tanaka, Isao

2006-10-24

Dipeptidyl peptidase IV (DPP-IV) inhibitors are expected to become a useful new class of anti-diabetic agent. The aim of the present study is to characterize the in vitro and in vivo profile of E3024, 3-but-2-ynyl-5-methyl-2-piperazin-1-yl-3,5-dihydro-4H-imidazo[4,5-d]pyridazin-4-one tosylate, which is a novel imidazopyridazinone-derived DPP-IV inhibitor. E3024 inhibited recombinant human and mouse DPP-IV with IC50 values of approximately 100 nM. E3024 inhibited DPP-IV in human, mouse, rat and canine plasma with IC50 values of 140 to 400 nM. In contrast, E3024 did not inhibit DPP-8 or DPP-9 activity. Kinetic analysis indicated that E3024 is a competitive DPP-IV inhibitor. In Zucker fa/fa rats, E3024 (1 mg/kg) reduced glucose excursion after glucose load, with increases in plasma insulin and active glucagon-like peptide-1 levels. In fasted rats, this compound did not cause hypoglycemia. In a rat 4-week toxicological study, no notable changes were found at doses up to 750 mg/kg. The present preclinical studies indicate that E3024 is a novel selective DPP-IV inhibitor with anti-diabetic effects and a good safety profile.

Inhibition of dipeptidyl peptidase 4 regulates microvascular endothelial growth induced by inflammatory cytokines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takasawa, Wataru; Ohnuma, Kei; Hatano, Ryo

2010-10-08

Research highlights: {yields} TNF-{alpha} or IL-1{beta} induces EC proliferation with reduction of CD26 expression. {yields} CD26 siRNA or DPP-4 inhibition enhances TNF-{alpha} or IL-1{beta}-induced EC proliferation. {yields} Loss of CD26/DPP-4 enhances aortic sprouting induced by TNF-{alpha} or IL-1{beta}. {yields} Capillary formation induced by TNF-{alpha} or IL-1{beta} is enahced in the CD26{sup -/-} mice. -- Abstract: CD26/DPP-4 is abundantly expressed on capillary of inflamed lesion as well as effector T cells. Recently, CD26/dipeptidyl peptidase 4 (DPP-4) inhibition has been used as a novel oral therapeutic approach for patients with type 2 diabetes. While accumulating data indicate that vascular inflammation is amore » key feature of both micro- and macro-vascular complications in diabetes, the direct role of CD26/DPP-4 in endothelial biology is to be elucidated. We herein showed that proinflammatory cytokines such as tumor necrosis factor or interleukin-1 reduce expression of CD26 on microvascular endothelial cells, and that genetical or pharmacological inhibition of CD26/DPP-4 enhances endothelial growth both in vitro and in vivo. With DPP-4 inhibitors being used widely in the treatment of type 2 diabetes, our data strongly suggest that DPP-4 inhibition plays a pivotal role in endothelial growth and may have a potential role in the recovery of local circulation following diabetic vascular complications.« less

30 CFR 550.252 - What environmental monitoring information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What environmental monitoring information must... Coordination Documents (docd) § 550.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must accompany your DPP or...

30 CFR 550.252 - What environmental monitoring information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What environmental monitoring information must... Coordination Documents (docd) § 550.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must accompany your DPP or...

30 CFR 550.252 - What environmental monitoring information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What environmental monitoring information must... Coordination Documents (docd) § 550.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must accompany your DPP or...

30 CFR 250.252 - What environmental monitoring information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What environmental monitoring information must... Documents (docd) § 250.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must accompany your DPP or DOCD: (a...

30 CFR 550.273 - How do I submit a modified DPP or DOCD or resubmit a disapproved DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Review and Decision Process for the Dpp Or Docd § 550.273 How do I submit a...

30 CFR 550.273 - How do I submit a modified DPP or DOCD or resubmit a disapproved DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Review and Decision Process for the Dpp Or Docd § 550.273 How do I submit a...

30 CFR 250.253 - What lease stipulations information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What lease stipulations information must accompany the DPP or DOCD? 250.253 Section 250.253 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination...

30 CFR 250.262 - What administrative information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What administrative information must accompany the DPP or DOCD? 250.262 Section 250.262 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

30 CFR 250.262 - What administrative information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What administrative information must accompany the DPP or DOCD? 250.262 Section 250.262 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination...

30 CFR 250.254 - What mitigation measures information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What mitigation measures information must accompany the DPP or DOCD? 250.254 Section 250.254 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination...

30 CFR 250.259 - What sulphur operations information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What sulphur operations information must accompany the DPP or DOCD? 250.259 Section 250.259 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination...

30 CFR 250.241 - What must the DPP or DOCD include?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What must the DPP or DOCD include? 250.241 Section 250.241 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT... and Information Contents of Development and Production Plans (dpp) and Development Operations...

30 CFR 250.255 - What decommissioning information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What decommissioning information must accompany the DPP or DOCD? 250.255 Section 250.255 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

30 CFR 250.255 - What decommissioning information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What decommissioning information must accompany the DPP or DOCD? 250.255 Section 250.255 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination...

30 CFR 250.246 - What mineral resource conservation information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development Operations... DPP or DOCD: (a) Technology and reservoir engineering practices and procedures. A description of the...

30 CFR 250.246 - What mineral resource conservation information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development Operations Coordination Documents (docd) § 250.246 What mineral resource... information, as applicable, must accompany your DPP or DOCD: (a) Technology and reservoir engineering...

30 CFR 250.242 - What information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Coastal zone management information required by § 250.260; (s) Environmental impact analysis information... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What information must accompany the DPP or DOCD... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development...

Omarigliptin (MK-3102): A Novel Long-Acting DPP-4 Inhibitor for Once-Weekly Treatment of Type 2 Diabetes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biftu, Tesfaye; Sinha-Roy, Ranabir; Chen, Ping

In our effort to discover DPP-4 inhibitors with added benefits over currently commercially available DPP-4 inhibitors, MK-3102 (omarigliptin), was identified as a potent and selective dipeptidyl peptidase 4 (DPP-4) inhibitor with an excellent pharmacokinetic profile amenable for once-weekly human dosing and selected as a clinical development candidate. This manuscript summarizes the mechanism of action, scientific rationale, medicinal chemistry, pharmacokinetic properties, and human efficacy data for omarigliptin, which is currently in phase 3 clinical development.

Dpp Signaling Activity Requires Pentagone to Scale with Tissue Size in the Growing Drosophila Wing Imaginal Disc

PubMed Central

Pyrowolakis, George; Bergmann, Sven; Affolter, Markus

2011-01-01

The wing of the fruit fly, Drosophila melanogaster, with its simple, two-dimensional structure, is a model organ well suited for a systems biology approach. The wing arises from an epithelial sac referred to as the wing imaginal disc, which undergoes a phase of massive growth and concomitant patterning during larval stages. The Decapentaplegic (Dpp) morphogen plays a central role in wing formation with its ability to co-coordinately regulate patterning and growth. Here, we asked whether the Dpp signaling activity scales, i.e. expands proportionally, with the growing wing imaginal disc. Using new methods for spatial and temporal quantification of Dpp activity and its scaling properties, we found that the Dpp response scales with the size of the growing tissue. Notably, scaling is not perfect at all positions in the field and the scaling of target gene domains is ensured specifically where they define vein positions. We also found that the target gene domains are not defined at constant concentration thresholds of the downstream Dpp activity gradients P-Mad and Brinker. Most interestingly, Pentagone, an important secreted feedback regulator of the pathway, plays a central role in scaling and acts as an expander of the Dpp gradient during disc growth. PMID:22039350

Histoplasma capsulatum Encodes a Dipeptidyl Peptidase Active against the Mammalian Immunoregulatory Peptide, Substance P

PubMed Central

Cooper, Kendal G.; Zarnowski, Robert; Woods, Jon P.

2009-01-01

The pathogenic fungus Histoplasma capsulatum secretes dipeptidyl peptidase (Dpp) IV enzyme activity and has two putative DPPIV homologs (HcDPPIVA and HcDPPIVB). We previously showed that HcDPPIVB is the gene responsible for the majority of secreted DppIV activity in H. capsulatum culture supernatant, while we could not detect any functional contribution from HcDPPIVA. In order to determine whether HcDPPIVA encodes a functional DppIV enzyme, we expressed HcDPPIVA in Pichia pastoris and purified the recombinant protein. The recombinant enzyme cleaved synthetic DppIV substrates and had similar biochemical properties to other described DppIV enzymes, with temperature and pH optima of 42°C and 8, respectively. Recombinant HcDppIVA cleaved the host immunoregulatory peptide substance P, indicating the enzyme has the potential to affect the immune response during infection. Expression of HcDPPIVA under heterologous regulatory sequences in H. capsulatum resulted in increased secreted DppIV activity, indicating that the encoded protein can be expressed and secreted by its native organism. However, HcDPPIVA was not required for virulence in a murine model of histoplasmosis. This work reports a fungal enzyme that can function to cleave the immunomodulatory host peptide substance P. PMID:19384411

A novel DPP6 isoform (DPP6-E) can account for differences between neuronal and reconstituted A-type K(+) channels.

PubMed

Maffie, Jonathon; Blenkinsop, Timothy; Rudy, Bernardo

2009-01-16

The channels mediating most of the somatodendritic A-type K(+) current in neurons are thought to be ternary complexes of Kv4 pore-forming subunits and two types of auxiliary subunits, the K(+) channel interacting proteins (KChIPs) and dipeptidyl-peptidase-like (DPPL) proteins. The channels expressed in heterologous expression systems by mixtures of Kv4.2, KChIP1 and DPP6-S resemble in many properties the A-type current in hippocampal CA1 pyramidal neurons and cerebellar granule cells, neurons with prominent A-type K(+) currents. However, the native currents have faster kinetics. Moreover, the A-type currents in neurons in intermediary layers of the superior colliculus have even faster inactivating rates. We have characterized a new DPP6 spliced isoform, DPP6-E, that produces in heterologous cells ternary Kv4 channels with very fast kinetics. DPP6-E is selectively expressed in a few neuronal populations in brain including cerebellar granule neurons, hippocampal pyramidal cells and neurons in intermediary layers of the superior colliculus. The effects of DPP6-E explain past discrepancies between reconstituted and native Kv4 channels in some neurons, and contributes to the diversity of A-type K(+) currents in neurons.

Strong Association between Plasma Dipeptidyl Peptidase-4 Activity and Impaired Cognitive Function in Elderly Population with Normal Glucose Tolerance.

PubMed

Chen, Bo; Zheng, Tianpeng; Qin, Linyuan; Hu, Xueping; Zhang, Xiaoxi; Liu, Yihong; Liu, Hongbo; Qin, Shenghua; Li, Gang; Li, Qinghua

2017-01-01

Objective: Inflammation, oxidative stress, and decreased glucagon-like peptide-1 (GLP-1) are risk factors for cognitive impairment. Dipeptidyl peptidase-4 (DPP4) was identified as a novel adipokine capable of enhancing these risk factors. Hence, we investigated the relationship between plasma DPP4 activity and impaired cognitive function in elderly Chinese population with normal glucose tolerance (NGT). Methods: We performed a cross-sectional study using data from 1229 elderly participants (60 years or older) in Guilin. Plasma DPP4 activity, oxidative stress parameters, fasting active GLP-1, and inflammatory markers were measured in all participants. Impaired cognitive function was diagnosed according to the National Institute on Aging-Alzheimer's Association workgroups criteria. Results: Participants in the upper quartile of plasma DPP4 activity had higher C-reactive protein (CRP), interleukin-6 (IL-6), 8-iso-PGF2a, nitrotyrosine, and lower GLP-1 and Montreal Cognitive Assessment (MoCA) scores compared with those in the lowest quartile ( P < 0.001). The odds ratios (ORs) for increased CRP, IL-6, 8-iso-PGF2a, nitrotyrosine, and decreased active GLP-1 were higher with increasing DPP4 quartiles after adjustment for confounders (all P < 0.001). In the highest DPP4 quartile, impaired cognitive function risk was higher (OR, 2.26; 95% confidence interval, 1.36-3.76) than in the lowest quartile after adjustment for potential confounders. The risk for impaired cognitive function increased more with higher levels of DPP4 activity, nitrotyrosine and 8-iso-PGF2a ( P < 0.05), but not with higher IL-6, CRP or lower GLP-1. Conclusion: Plasma DPP4 activity is significantly and independently associated with impaired cognitive function, mainly executive, in elderly Chinese population with NGT. The underlying mechanisms for this association may be partly attributed to the effect of DPP4 on oxidative stress. Plasma DPP4 activity might serve as a risk biomarker or therapeutic target for the prevention and treatment of impaired cognitive function.

Pharmacovigilance Evaluation of the Association Between DPP-4 Inhibitors and Heart Failure: Stimulated Reporting and Moderation by Drug Interactions.

PubMed

Fadini, Gian Paolo; Sarangdhar, Mayur; Avogaro, Angelo

2018-04-01

In the SAVOR-TIMI trial, the risk of heart failure (HF) was increased by 27% in T2D patients randomized to the dipeptidyl peptidase-4 inhibitor (DPP4i) saxagliptin. Other studies have provided inconsistent results regarding this association. Herein, we performed a pharmacovigilance analysis of the rate of HF associated with DPP4is, focusing on stimulated reporting and moderation by drug-drug interactions. We mined the FDA adverse event (AE) reporting system (FAERS) from 2004q1 to 2017q3, including a total of 9906,642 AE reports. Rates (/1000 reports) of HF within the reports for DPP4is and reports for other antidiabetic drugs were calculated for the period up to 2013q3 (date of publication of the SAVOR-TIMI trial results) and from 2013q4 to 2017q3. Analyses were refined by filtering according to therapeutic area, concomitant diseases and drugs, and competing AEs. The rate of HF among the AE reports filed for DPP4is significantly increased after 2013q3, especially for saxagliptin. When compared to non-insulin non-glitazone antidiabetic drugs, the proportional reporting ratio (PRR) of HF for DPP4is was 0.62 (95% CI 0.56-0.68) up to 2013q3 and 2.12 (95% CI 1.96-2.28) from 2013q4 to 2017q3. This stimulated reporting was consistent in subanalyses based on the presence/absence of cardiac disorders and after controlling for competing AEs. The rate of HF among AE reports for DPP4is was modestly moderated by the concomitant use of metformin (- 15%) and strongly moderated by the concomitant use of SGLT2 inhibitors (- 63%), even after excluding competing AEs. Within the FAERS, the association between HF and DPP4is was biased by stimulated reporting, implying that the publication of the SAVOR-TIMI trial and the subsequent regulatory warnings primed clinicians to report HF events in DPP4i users as drug-related AEs. The rate of HF associated with DPP4is was moderated when they were used in combination with SGLT2 inhibitors.

Visceral fat obesity increases serum DPP-4 levels in men with type 2 diabetes mellitus.

PubMed

Tanaka, Sayuri; Kanazawa, Ippei; Notsu, Masakazu; Sugimoto, Toshitsugu

2016-06-01

The relationship between serum DPP-4 level and visceral fat mass is still unclear in type 2 diabetes mellitus (T2DM). This study thus aimed to examine the association of visceral fat accumulation and metabolic syndrome with serum DPP-4 levels in T2DM. Visceral and subcutaneous fat areas were evaluated by performing computed tomography scan in 135 men with T2DM, who had never taken DPP-4 inhibitors or GLP-1 receptor agonists. We investigated the association between serum DPP-4 levels and visceral fat area as well as the presence of metabolic syndrome. Multiple regression analysis adjusted for age, duration of T2DM, body mass index, serum creatinine, and HbA1c showed that serum DPP-4 levels were positively associated with visceral fat area (β=0.25, p=0.04), but not subcutaneous fat area (β=-0.18, p=0.13). In logistic regression analyses adjusted for the confounding factors described above, serum DPP-4 levels were positively associated with visceral fat obesity and metabolic syndrome [odds ratio (OR)=1.63, 95% confidence interval (CI)=1.00-2.66 per standard deviation (SD) increase, p=0.04; OR=1.77, 95%CI=1.09-2.88 per SD increase, p=0.02, respectively]. The present study showed that serum DPP-4 level was positively and specifically associated with accumulation of visceral fat and the presence of metabolic syndrome in men with T2DM. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

30 CFR 550.250 - What oil and hazardous substance spills information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development... accompany your DPP or DOCD: (a) Oil spill response planning. The material required under paragraph (a)(1) or... conduct your proposed development and production activities prepared according to the requirements of 30...

30 CFR 550.250 - What oil and hazardous substance spills information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development... accompany your DPP or DOCD: (a) Oil spill response planning. The material required under paragraph (a)(1) or... conduct your proposed development and production activities prepared according to the requirements of 30...

30 CFR 550.250 - What oil and hazardous substance spills information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development... accompany your DPP or DOCD: (a) Oil spill response planning. The material required under paragraph (a)(1) or... conduct your proposed development and production activities prepared according to the requirements of 30...

30 CFR 550.249 - What air emissions information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... and Information Contents of Development and Production Plans (dpp) and Development Operations Coordination Documents (docd) § 550.249 What air emissions information must accompany the DPP or DOCD? The... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What air emissions information must accompany...

30 CFR 550.249 - What air emissions information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... and Information Contents of Development and Production Plans (dpp) and Development Operations Coordination Documents (docd) § 550.249 What air emissions information must accompany the DPP or DOCD? The... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What air emissions information must accompany...

30 CFR 550.249 - What air emissions information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... and Information Contents of Development and Production Plans (dpp) and Development Operations Coordination Documents (docd) § 550.249 What air emissions information must accompany the DPP or DOCD? The... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What air emissions information must accompany...

30 CFR 250.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What biological, physical, and socioeconomic information must accompany the DPP or DOCD? 250.247 Section 250.247 Mineral Resources MINERALS MANAGEMENT... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development...

30 CFR 250.256 - What related facilities and operations information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What related facilities and operations information must accompany the DPP or DOCD? 250.256 Section 250.256 Mineral Resources MINERALS MANAGEMENT... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development...

30 CFR 250.253 - What lease stipulations information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What lease stipulations information must accompany the DPP or DOCD? 250.253 Section 250.253 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

30 CFR 250.259 - What sulphur operations information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What sulphur operations information must accompany the DPP or DOCD? 250.259 Section 250.259 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

30 CFR 250.250 - What oil and hazardous substance spills information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What oil and hazardous substance spills information must accompany the DPP or DOCD? 250.250 Section 250.250 Mineral Resources MINERALS MANAGEMENT... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development...

30 CFR 250.243 - What general information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What general information must accompany the DPP or DOCD? 250.243 Section 250.243 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development...

An easy one-pot synthesis of diverse 2,5-di(2-pyridyl)pyrroles: a versatile entry point to metal complexes of functionalised, meridial and tridentate 2,5-di(2-pyridyl)pyrrolato ligands.

PubMed

McSkimming, Alex; Diachenko, Vera; London, Rachel; Olrich, Kiara; Onie, C Jessica; Bhadbhade, Mohan M; Bucknall, Martin P; Read, Roger W; Colbran, Stephen B

2014-09-01

A wide variety of 2,5-di(2-pyridyl)pyrroles (dppHs) substituted at the C3 and C4 positions of the pyrrole core were obtained by direct condensation of a 2-pyridylcarboxaldehyde (2 equiv), an α-methylene ketone with at least one electron-withdrawing substituent and ammonium acetate. A novel 2,5-di(1,10-phenanthrolin-2-yl)pyrrole was also characterised. The dppHs provide a direct, quick entry to dipyridylpyrrolato (dpp(-) )-metal complexes. The meridial tridentate dpp(-) ligand is a useful anionic analogue of the terpyridyl ligand. The first (dpp)Ru complexes are described; the 3,4-substitution of the central pyrrole significantly perturbs the potentials of the redox processes of these complexes. A [(dpp)Ru(bpy)(MeCN)](+) (bpy=2,2'-bipyridine) complex is an electrocatalyst for the reductive disproportionation of carbon dioxide to carbon monoxide and the carbonate ion. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Structural and mutational analyses of dipeptidyl peptidase 11 from Porphyromonas gingivalis reveal the molecular basis for strict substrate specificity

PubMed Central

Sakamoto, Yasumitsu; Suzuki, Yoshiyuki; Iizuka, Ippei; Tateoka, Chika; Roppongi, Saori; Fujimoto, Mayu; Inaka, Koji; Tanaka, Hiroaki; Yamada, Mitsugu; Ohta, Kazunori; Gouda, Hiroaki; Nonaka, Takamasa; Ogasawara, Wataru; Tanaka, Nobutada

2015-01-01

The dipeptidyl peptidase 11 from Porphyromonas gingivalis (PgDPP11) belongs to the S46 family of serine peptidases and preferentially cleaves substrates with Asp/Glu at the P1 position. The molecular mechanism underlying the substrate specificity of PgDPP11, however, is unknown. Here, we report the crystal structure of PgDPP11. The enzyme contains a catalytic domain with a typical double β-barrel fold and a recently identified regulatory α-helical domain. Crystal structure analyses, docking studies, and biochemical studies revealed that the side chain of Arg673 in the S1 subsite is essential for recognition of the Asp/Glu side chain at the P1 position of the bound substrate. Because S46 peptidases are not found in mammals and the Arg673 is conserved among DPP11s, we anticipate that DPP11s could be utilised as targets for antibiotics. In addition, the present structure analyses could be useful templates for the design of specific inhibitors of DPP11s from pathogenic organisms. PMID:26057589

Identification of novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides in camel milk protein hydrolysates.

PubMed

Nongonierma, Alice B; Paolella, Sara; Mudgil, Priti; Maqsood, Sajid; FitzGerald, Richard J

2018-04-01

Nine novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides (FLQY, FQLGASPY, ILDKEGIDY, ILELA, LLQLEAIR, LPVP, LQALHQGQIV, MPVQA and SPVVPF) were identified in camel milk proteins hydrolysed with trypsin. This was achieved using a sequential approach combining liquid chromatography tandem mass spectrometry (LC-MS/MS), qualitative/quantitative structure activity relationship (QSAR) and confirmatory studies with synthetic peptides. The most potent camel milk protein-derived DPP-IV inhibitory peptides, LPVP and MPVQA, had DPP-IV half maximal inhibitory concentrations (IC 50 ) of 87.0 ± 3.2 and 93.3 ± 8.0 µM, respectively. DPP-IV inhibitory peptide sequences identified within camel and bovine milk protein hydrolysates generated under the same hydrolysis conditions differ. This was linked to differences in enzyme selectivity for peptide bond cleavage of camel and bovine milk proteins as well as dissimilarities in their amino acid sequences. Camel milk proteins contain novel DPP-IV inhibitory peptides which may play a role in the regulation of glycaemia in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

Macrocarpal C isolated from Eucalyptus globulus inhibits dipeptidyl peptidase 4 in an aggregated form.

PubMed

Kato, Eisuke; Kawakami, Kazuhiro; Kawabata, Jun

2018-12-01

Dipeptidyl peptidase 4 (DPP-4) inhibitors are used for the treatment of type-2 diabetes mellitus. Various synthetic inhibitors have been developed to date, and plants containing natural DPP-4 inhibitors have also been identified. Here, 13 plant samples were tested for their DPP-4 inhibitory activity. Macrocarpals A-C were isolated from Eucalyptus globulus through activity-guided fractionation and shown to be DPP-4 inhibitors. Of these, macrocarpal C showed the highest inhibitory activity, demonstrating an inhibition curve characterised by a pronounced increase in activity within a narrow concentration range. Evaluation of macrocarpal C solution by turbidity, nuclear magnetic resonance spectroscopy and mass spectrometry indicated its aggregation, which may explain the characteristics of the inhibition curve. These findings will be valuable for further study of potential small molecule DPP-4 inhibitors.

Dipeptidyl peptidase-4 greatly contributes to the hydrolysis of vildagliptin in human liver.

PubMed

Asakura, Mitsutoshi; Fujii, Hideaki; Atsuda, Koichiro; Itoh, Tomoo; Fujiwara, Ryoichi

2015-04-01

The major metabolic pathway of vildagliptin in mice, rats, dogs, and humans is hydrolysis at the cyano group to produce a carboxylic acid metabolite M20.7 (LAY151), whereas the major metabolic enzyme of vildagliptin has not been identified. In the present study, we determined the contribution rate of dipeptidyl peptidase-4 (DPP-4) to the hydrolysis of vildagliptin in the liver. We performed hydrolysis assay of the cyano group of vildagliptin using mouse, rat, and human liver samples. Additionally, DPP-4 activities in each liver sample were assessed by DPP-4 activity assay using the synthetic substrate H-glycyl-prolyl-7-amino-4-methylcoumarin (Gly-Pro-AMC). M20.7 formation rates in liver microsomes were higher than those in liver cytosol. M20.7 formation rate was significantly positively correlated with the DPP-4 activity using Gly-Pro-AMC in liver samples (r = 0.917, P < 0.01). The formation of M20.7 in mouse, rat, and human liver S9 fraction was inhibited by sitagliptin, a selective DPP-4 inhibitor. These findings indicate that DPP-4 is greatly involved in vildagliptin hydrolysis in the liver. Additionally, we established stable single expression systems of human DPP-4 and its R623Q mutant, which is the nonsynonymous single-nucleotide polymorphism of human DPP-4, in human embryonic kidney 293 (HEK293) cells to investigate the effect of R623Q mutant on vildagliptin-hydrolyzing activity. M20.7 formation rate in HEK293 cells expressing human DPP-4 was significantly higher than that in control HEK293 cells. Interestingly, R623Q mutation resulted in a decrease of the vildagliptin-hydrolyzing activity. Our findings might be useful for the prediction of interindividual variability in vildagliptin pharmacokinetics. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Suppression of Food Intake by Glucagon-Like Peptide-1 Receptor Agonists: Relative Potencies and Role of Dipeptidyl Peptidase-4

PubMed Central

Jessen, Lene; Aulinger, Benedikt A.; Hassel, Jonathan L.; Roy, Kyle J.; Smith, Eric P.; Greer, Todd M.; Woods, Stephen C.; Seeley, Randy J.

2012-01-01

Administration of the glucagon-like peptide-1 (GLP-1) receptor agonists GLP-1 and exendin-4 (Ex-4) directly into the central nervous system decreases food intake. But although Ex-4 potently suppresses food intake after peripheral administration, the effects of parenteral GLP-1 are variable and not as strong. A plausible explanation for these effects is the rapid inactivation of circulating GLP-1 by dipeptidyl peptidase-4 (DPP-4), an enzyme that does not alter Ex-4 activity. To test this hypothesis, we assessed the relative potency of Ex-4 and GLP-1 under conditions in which DPP-4 activity was reduced. Outbred rats, wild-type mice, and mice with a targeted deletion of DPP-4 (Dpp4−/−) were treated with GLP-1 alone or in combination with the DPP-4 inhibitor vildagliptin, Ex-4, or saline, and food intake was measured. GLP-1 alone, even at high doses, did not affect feeding in wild-type mice or rats but did reduce food intake when combined with vildagliptin or given to Dpp4−/− mice. Despite plasma clearance similar to DPP-4-protected GLP-1, equimolar Ex-4 caused greater anorexia than vildagliptin plus GLP-1. To determine whether supraphysiological levels of endogenous GLP-1 would suppress food intake if protected from DPP-4, rats with Roux-en-Y gastric bypass and significantly elevated postprandial plasma GLP-1 received vildagliptin or saline. Despite 5-fold greater postprandial GLP-1 in these animals, vildagliptin did not affect food intake in Roux-en-Y gastric bypass rats. Thus, in both mice and rats, peripheral GLP-1 reduces food intake significantly less than Ex-4, even when protected from DPP-4. These findings suggest distinct potencies of GLP-1 receptor agonists on food intake that cannot be explained by plasma pharmacokinetics. PMID:23033273

Increased plasma DPP4 activities predict new-onset atherosclerosis in association with its proinflammatory effects in Chinese over a four year period: A prospective study.

PubMed

Zheng, T P; Yang, F; Gao, Y; Baskota, A; Chen, T; Tian, H M; Ran, X W

2014-08-01

DPP4, a novel proinflammatory cytokine, is involved in the inflammatory process through its interaction with IGF-II/M6P receptor. We aimed to investigate whether it could predict new-onset atherosclerosis in Chinese. A prospective study was conducted of 590 adults (213 men and 377 women) aged 18-70 years without atherosclerosis examined in 2007(baseline) and 2011(follow-up). Circulating DPP4 activity, inflammatory markers, IGF-II/M6P receptor and common carotid artery Intima-Media Thickness (C-IMT) were measured at baseline and four years later. At baseline, individuals in the highest quartile of DPP4 activity had higher age, WHR, BMI, SBP, fasting insulin, 2h-PG, TG, LDL-C, IL-6, hs-CRP, IGF-II/M6P-R, C-IMT and lower HDL-C compared with individuals in the lowest quartile. After a 4-year follow-up, 71 individuals developed atherosclerosis. In multiple linear regression analysis, baseline DPP4 activity was an independent predictor of an increase in inflammatory markers, IGF-II/M6P receptor, and C-IMT over a 4-year period (all P < 0.01). In multivariable-adjusted models, the odds ratio (OR) for incident atherosclerosis comparing the highest with the lowest quartiles of DPP4 activity was 3.17 (95%CI 1.33-7.58) after adjustment for confounding risk factors (P = 0.009). The incidence of atherosclerosis owing to DPP4 activity increased by 12.41%. DPP4 activity is an important predictor of the onset of inflammation and atherosclerosis in apparently healthy Chinese. This finding may have important implications for understanding the proinflammatory role of DPP-4 in the pathogenesis of atherosclerosis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Wound healing effects of dipeptidyl peptidase-4 inhibitors: An emerging concept in management of diabetic foot ulcer-A review.

PubMed

Saboo, Apoorva; Rathnayake, Ayeshmanthe; Vangaveti, Venkat N; Malabu, Usman H

2016-01-01

Dipeptidyl peptidase-4 (DPP-4) inhibitors have a well-known effect on glycaemic control in patients with diabetes but little is known on their wound healing role in this group of population. This paper reviews the effects of DPP-4 inhibitors on wound healing of diabetic foot ulcers. Published data on effects and mechanism of DDP-4 inhibitors on wound healing were derived from Medline, PubMed and Google Scholar search of English language literature from 1994 to 2014 using the key words such as "DPP-4 inhibitors", "endothelial healing" "diabetes" and "chronic ulcers". DPP-4 inhibitors show a potential benefit in processes of wound healing in diabetic chronic foot ulcers. The enzyme inhibitors promote recruitment of endothelial progenitor cells and allow the final scaffolding of wounds. Furthermore DPP-4 inhibitors augment angiogenesis and have widespread effects on optimising the immune response to persistent hypoxia in chronic diabetes wounds. DPP-4 inhibitors show promise in the local wound healing of diabetic foot ulcers in addition to its already established glycaemic control. In the light of high rate of amputations due to non-healing ulcers with profound psychological and economical liability, more investigations on the usefulness of DPP-4 inhibitors in the high risk diabetes population are needed. Copyright © 2015 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Structure⁻Activity Relationship and Molecular Docking of Natural Product Library Reveal Chrysin as a Novel Dipeptidyl Peptidase-4 (DPP-4) Inhibitor: An Integrated In Silico and In Vitro Study.

PubMed

Kalhotra, Poonam; Chittepu, Veera C S R; Osorio-Revilla, Guillermo; Gallardo-Velázquez, Tzayhri

2018-06-06

Numerous studies indicate that diets with a variety of fruits and vegetables decrease the incidence of severe diseases, like diabetes, obesity, and cancer. Diets contain a variety of bioactive compounds, and their features, like diverge scaffolds, and structural complexity make them the most successful source of potential leads or hits in the process of drug discovery and drug development. Recently, novel serine protease dipeptidyl peptidase-4 (DPP-4) inhibitors played a role in the management of diabetes, obesity, and cancer. This study describes the development of field template, field-based qualitative structure⁻activity relationship (SAR) model demonstrating DPP-4 inhibitors of natural origin, and the same model is used to screen virtually focused food database composed of polyphenols as potential DPP-4 inhibitors. Compounds’ similarity to field template, and novelty score “high and very high”, were used as primary criteria to identify novel DPP-4 inhibitors. Molecular docking simulations were performed on the resulting natural compounds using FlexX algorithm. Finally, one natural compound, chrysin, was chosen to be evaluated experimentally to demonstrate the applicability of constructed SAR model. This study provides the molecular insights necessary in the discovery of new leads as DPP-4 inhibitors, to improve the potency of existing DPP-4 natural inhibitors.

30 CFR 550.251 - If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP?

Code of Federal Regulations, 2013 CFR

2013-07-01

... production activities in the Alaska OCS Region, the following planning information must accompany your DPP... Region, what planning information must accompany the DPP? 550.251 Section 550.251 Mineral Resources... IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans...

30 CFR 550.251 - If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP?

Code of Federal Regulations, 2012 CFR

2012-07-01

... production activities in the Alaska OCS Region, the following planning information must accompany your DPP... Region, what planning information must accompany the DPP? 550.251 Section 550.251 Mineral Resources... IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans...

30 CFR 550.251 - If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP?

Code of Federal Regulations, 2014 CFR

2014-07-01

... production activities in the Alaska OCS Region, the following planning information must accompany your DPP... Region, what planning information must accompany the DPP? 550.251 Section 550.251 Mineral Resources... IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans...

30 CFR 250.271 - For what reasons will MMS disapprove the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Decision Process for the Dpp Or Docd § 250.271 For what reasons will MMS disapprove the DPP or DOCD? The...), implementing regulations, or other applicable Federal laws. (b) No consistency concurrence. (1) An affected State has not yet issued a final decision on your coastal zone consistency certification (see 15 CFR 930...

30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What geological and geophysical (G&G... Operations Coordination Documents (docd) § 550.244 What geological and geophysical (G&G) information must accompany the DPP or DOCD? The following G&G information must accompany your DPP or DOCD: (a) Geological...

30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What geological and geophysical (G&G... Operations Coordination Documents (docd) § 550.244 What geological and geophysical (G&G) information must accompany the DPP or DOCD? The following G&G information must accompany your DPP or DOCD: (a) Geological...

30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What geological and geophysical (G&G... Operations Coordination Documents (docd) § 550.244 What geological and geophysical (G&G) information must accompany the DPP or DOCD? The following G&G information must accompany your DPP or DOCD: (a) Geological...

30 CFR 550.269 - How will BOEM evaluate the environmental impacts of the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... impacts of the DPP or DOCD? 550.269 Section 550.269 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... environmental impacts of the DPP or DOCD? The Regional Supervisor will evaluate the environmental impacts of the... through 1508). (a) Environmental impact statement (EIS) declaration. At least once in each OCS planning...

30 CFR 250.261 - What environmental impact analysis (EIA) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... analysis (EIA) information must accompany the DPP or DOCD? The following EIA information must accompany... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What environmental impact analysis (EIA) information must accompany the DPP or DOCD? 250.261 Section 250.261 Mineral Resources BUREAU OF OCEAN ENERGY...

Dual Role of Jun N-Terminal Kinase Activity in Bone Morphogenetic Protein-Mediated Drosophila Ventral Head Development.

PubMed

Park, Sung Yeon; Stultz, Brian G; Hursh, Deborah A

2015-12-01

The Drosophila bone morphogenetic protein encoded by decapentaplegic (dpp) controls ventral head morphogenesis by expression in the head primordia, eye-antennal imaginal discs. These are epithelial sacs made of two layers: columnar disc proper cells and squamous cells of the peripodial epithelium. dpp expression related to head formation occurs in the peripodial epithelium; cis-regulatory mutations disrupting this expression display defects in sensory vibrissae, rostral membrane, gena, and maxillary palps. Here we document that disruption of this dpp expression causes apoptosis in peripodial cells and underlying disc proper cells. We further show that peripodial Dpp acts directly on the disc proper, indicating that Dpp must cross the disc lumen to act. We demonstrate that palp defects are mechanistically separable from the other mutant phenotypes; both are affected by the c-Jun N-terminal kinase pathway but in opposite ways. Slight reduction of both Jun N-terminal kinase and Dpp activity in peripodial cells causes stronger vibrissae, rostral membrane, and gena defects than Dpp alone; additionally, strong reduction of Jun N-terminal kinase activity alone causes identical defects. A more severe reduction of dpp results in similar vibrissae, rostral membrane, and gena defects, but also causes mutant maxillary palps. This latter defect is correlated with increased peripodial Jun N-terminal kinase activity and can be caused solely by ectopic activation of Jun N-terminal kinase. We conclude that formation of sensory vibrissae, rostral membrane, and gena tissue in head morphogenesis requires the action of Jun N-terminal kinase in peripodial cells, while excessive Jun N-terminal kinase signaling in these same cells inhibits the formation of maxillary palps. Copyright © 2015 by the Genetics Society of America.

Comparison of the susceptibility of porcine and human dipeptidyl-peptidase IV to inhibition by protein-derived peptides.

PubMed

Lacroix, Isabelle M E; Li-Chan, Eunice C Y

2015-07-01

The enzyme dipeptidyl-peptidase IV (DPP-IV) is recognized to be a promising target for the management of type 2 diabetes. Over the last decade, numerous synthetic molecules and more recently, peptides from dietary proteins, have been reported to be able to inhibit DPP-IV activity. Most studies that have investigated the in vitro effect of these inhibitors have used porcine or human DPP-IV. Although structurally alike, it is unclear whether these two species display similar inhibition patterns. Therefore, the objective of this study was to compare the effects of protein-derived peptides on the activity of porcine and recombinant human DPP-IV. The two species showed different inhibition susceptibility to 43 of the 62 peptide sequences investigated. While 37 protein-derived peptides were more effective at inhibiting the porcine DPP-IV, only six caused a stronger inhibition of the activity of the human enzyme. Although the peptides WR, IPIQY and WCKDDQNPHS were found to be among the most potent inhibitors of both species, the inhibitory effect was greater on the porcine enzyme than on human DPP-IV (αKi or Ki=11.5, 13.4, 13.3 μM and 31.4, 28.2, 75.0 μM for porcine and human DPP-IV, respectively). Investigation into the mode of action of the most effective inhibitory peptides revealed that both species were inhibited in a similar manner by short fragments (≤5 amino acid residues), but that some of the longer peptides acted differently on the enzymes. This study shows that porcine DPP-IV is generally inhibited with greater potency by protein-derived peptides than is the human enzyme. Copyright © 2015 Elsevier Inc. All rights reserved.

New naphtho[1,2-b:5,6-b‧]difuran based two-dimensional conjugated small molecules for photovoltaic application

NASA Astrophysics Data System (ADS)

Peng, Hongjian; Luan, Xiangfeng; Qiu, Lixia; Li, Hang; Liu, Ye; Zou, Yingping

2017-10-01

Two new A-D-A small molecules with alkoxyphenyl and alkylthiophenyl-substituted naphtho[1,2-b:5,6-b‧]difuran (NDF) as the central building block named NDFPO-DPP and NDFPS-DPP were synthesized and firstly used as donor materials in organic solar cells (OSCs). The effects of the alkoxyphenyl and alkylthiophenyl side chains on the NDF unit have been investigated. With a single atom variation from O to S, NDFPS-DPP exhibited lower HOMO energy levels than its counterpart NDFPO-DPP, which resulted in enhanced Voc. The device based on NDFPO-DPP with thermal annealing exhibited a better PCE of 3.10% due to the higher and more balanced hole and electron mobilities. The investigations show that NDF could be a promising building block in OSCs via rational molecular structure design and device optimizations.

30 CFR 250.281 - What must I do to conduct activities under the approved EP, DPP, or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

...: (1) All affected States with approved coastal zone management programs concur, or are conclusively presumed to concur, with the coastal zone consistency certification accompanying your EP under section 307... interest of national security; (3) If an affected State objects to the coastal zone consistency...

"Cooking and Active Leisure" TAS Program, Spain: a Program Impact Pathways (PIP) analysis.

PubMed

Roura, Elena; Pareja, Sara Lucía; Milá, Raimon; Cinca, Núria

2014-09-01

The "Cooking and Active Leisure" Tu y Alícia por la Salud (CAL-TAS) Program is a school-based pilot that addresses healthy lifestyle needs of Spanish secondary school students with initiatives that research has proven to improve dietary and physical activity behaviors. The objectives were to perform a Program Impact Pathways (PIP) analysis to describe key activities and processes of the CAL-TAS Program, identify Critical Quality Control Points (CCPs), and identify a suite of common indicators of healthy lifestyles to be applied across participant schools. The CAL-TAS Program designers and implementation team developed this PIP analysis through an iterative process and presented the results for feedback at the seven-country Healthy Lifestyles Program Evaluation Workshop held in Granada, Spain, 13-14 September 2013, under the auspices of the Mondelēz International Foundation. The team identified three PIP CCPs: teachers' motivation and training, changes in students' knowledge of healthy lifestyles, and changes in students' healthy lifestyle behavior. The selected indicators of the program's impact on healthy lifestyles are adequacy of food intake, level of knowledge of healthy lifestyles gained, and adequacy of physical activity level according to World Health Organization recommendations. A clear definition of impact indicators, as well as collection of accurate data on healthy lifestyle behaviors and knowledge, is essential to understanding the effectiveness of this program before it can be scaled up. CAL-TAS is an effective secondary school-based program encouraging healthy lifestyles. The PIP analysis was instrumental in identifying CCPs to sustain and improve the quality of the program. The team hopes to sustain and improve the program through these program evaluation recommendations.

30 CFR 250.270 - What decisions will MMS make on the DPP or DOCD and within what timeframe?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Review and Decision Process for the Dpp Or Docd § 250.270... provide monitoring information. (2) Require you to modify your proposed DPP or DOCD It fails to make...

30 CFR 550.270 - What decisions will BOEM make on the DPP or DOCD and within what timeframe?

Code of Federal Regulations, 2014 CFR

2014-07-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Review and Decision Process for the Dpp Or Docd § 550.270 What decisions... provide monitoring information. (2) Require you to modify your proposed DPP or DOCD, It fails to make...

30 CFR 250.272 - If a State objects to the DPP's or DOCD's coastal zone consistency certification, what can I do?

Code of Federal Regulations, 2010 CFR

2010-07-01

... coastal zone consistency certification, what can I do? 250.272 Section 250.272 Mineral Resources MINERALS... objects to the DPP's or DOCD's coastal zone consistency certification, what can I do? If an affected State objects to the coastal zone consistency certification accompanying your proposed or disapproved DPP or...

30 CFR 550.271 - For what reasons will BOEM disapprove the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false For what reasons will BOEM disapprove the DPP or DOCD? 550.271 Section 550.271 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... Information Review and Decision Process for the Dpp Or Docd § 550.271 For what reasons will BOEM disapprove...

30 CFR 550.269 - How will BOEM evaluate the environmental impacts of the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false How will BOEM evaluate the environmental impacts of the DPP or DOCD? 550.269 Section 550.269 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Review and Decision Process for the Dpp Or Docd § 550.269 How will BOEM evaluate the...

30 CFR 550.269 - How will BOEM evaluate the environmental impacts of the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false How will BOEM evaluate the environmental impacts of the DPP or DOCD? 550.269 Section 550.269 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Review and Decision Process for the Dpp Or Docd § 550.269 How will BOEM evaluate the...

30 CFR 550.271 - For what reasons will BOEM disapprove the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false For what reasons will BOEM disapprove the DPP or DOCD? 550.271 Section 550.271 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... Information Review and Decision Process for the Dpp Or Docd § 550.271 For what reasons will BOEM disapprove...

30 CFR 250.267 - What actions will MMS take after the DPP or DOCD is deemed submitted?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What actions will MMS take after the DPP or DOCD is deemed submitted? 250.267 Section 250.267 Mineral Resources MINERALS MANAGEMENT SERVICE... and Information Review and Decision Process for the Dpp Or Docd § 250.267 What actions will MMS take...

30 CFR 250.258 - What information on the onshore support facilities you will use must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What information on the onshore support facilities you will use must accompany the DPP or DOCD? 250.258 Section 250.258 Mineral Resources MINERALS... CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development...

Synthesis of Quaternary Ammonium Salts Based on Diketopyrrolopyrroles Skeletons and Their Applications in Copper Electroplating.

PubMed

Chen, Biao; Xu, Jie; Wang, Limin; Song, Longfeng; Wu, Shengying

2017-03-01

A series of DPP derivatives bearing quaternary ammonium salt centers with different lengths of carbon chains have been designed and synthesized. Their inhibition actions on copper electroplating were first investigated. A total of four diketopyrrolopyrrole (DPP) derivatives showed different inhibition capabilities on copper electroplating. To investigate interactions between metal surface and additives, we used quantum chemical calculations. Static and dynamic surface tension of four DPP derivatives had been measured, and the results showed DPP-10C (1c) with a faster-decreasing rate of dynamic surface tension among the four derivatives, which indicated higher adsorption rate of additive on the cathode surface and gives rise to stronger inhibiting effect of copper electrodeposition. Then, DPP-10C (1c) as the representative additive, was selected for the systematic study of the leveling influence during microvia filling through comprehensive electroplating tests. In addition, field-emission scanning electron microscope images and X-ray diffraction results showed the surface morphology, which indicated that addition of DPP derivative (1c) could lead a fine copper deposit and cause the preferential orientations of copper deposits to change from [220] to [111], which happened in particular at higher concentrations.

Increased avidity for Dpp/BMP2 maintains the proliferation of progenitors-like cells in the Drosophila eye.

PubMed

Neto, Marta; Aguilar-Hidalgo, Daniel; Casares, Fernando

2016-10-01

During organ development, the progenitor state is transient, and depends on specific combinations of transcription factors and extracellular signals. Not surprisingly, abnormal maintenance of progenitor transcription factors may lead to tissue overgrowth, and the concurrence of signals from the local environment is often critical to trigger this overgrowth. Therefore, identifying specific combinations of transcription factors/signals promoting -or opposing- proliferation in progenitors is essential to understand normal development and disease. We have investigated this issue using the Drosophila eye as model. Transcription factors hth and tsh are transiently expressed in eye progenitors causing the expansion of the progenitor pool. However, if their co-expression is maintained experimentally, cell proliferation continues and differentiation is halted. Here we show that Hth+Tsh-induced tissue overgrowth requires the BMP2 Dpp and the abnormal hyperactivation of its pathway. Rather than using autocrine Dpp expression, Hth+Tsh cells increase their avidity for Dpp, produced locally, by upregulating extracellular matrix components. During normal development, Dpp represses hth and tsh ensuring that the progenitor state is transient. However, cells in which Hth+Tsh expression is forcibly maintained use Dpp to enhance their proliferation. Copyright © 2016 Elsevier Inc. All rights reserved.

Finding a Potential Dipeptidyl Peptidase-4 (DPP-4) Inhibitor for Type-2 Diabetes Treatment Based on Molecular Docking, Pharmacophore Generation, and Molecular Dynamics Simulation

PubMed Central

Meduru, Harika; Wang, Yeng-Tseng; Tsai, Jeffrey J. P.; Chen, Yu-Ching

2016-01-01

Dipeptidyl peptidase-4 (DPP-4) is the vital enzyme that is responsible for inactivating intestinal peptides glucagon like peptide-1 (GLP-1) and Gastric inhibitory polypeptide (GIP), which stimulates a decline in blood glucose levels. The aim of this study was to explore the inhibition activity of small molecule inhibitors to DPP-4 following a computational strategy based on docking studies and molecular dynamics simulations. The thorough docking protocol we applied allowed us to derive good correlation parameters between the predicted binding affinities (pKi) of the DPP-4 inhibitors and the experimental activity values (pIC50). Based on molecular docking receptor-ligand interactions, pharmacophore generation was carried out in order to identify the binding modes of structurally diverse compounds in the receptor active site. Consideration of the permanence and flexibility of DPP-4 inhibitor complexes by means of molecular dynamics (MD) simulation specified that the inhibitors maintained the binding mode observed in the docking study. The present study helps generate new information for further structural optimization and can influence the development of new DPP-4 inhibitors discoveries in the treatment of type-2 diabetes. PMID:27304951

Finding a Potential Dipeptidyl Peptidase-4 (DPP-4) Inhibitor for Type-2 Diabetes Treatment Based on Molecular Docking, Pharmacophore Generation, and Molecular Dynamics Simulation.

PubMed

Meduru, Harika; Wang, Yeng-Tseng; Tsai, Jeffrey J P; Chen, Yu-Ching

2016-06-13

Dipeptidyl peptidase-4 (DPP-4) is the vital enzyme that is responsible for inactivating intestinal peptides glucagon like peptide-1 (GLP-1) and Gastric inhibitory polypeptide (GIP), which stimulates a decline in blood glucose levels. The aim of this study was to explore the inhibition activity of small molecule inhibitors to DPP-4 following a computational strategy based on docking studies and molecular dynamics simulations. The thorough docking protocol we applied allowed us to derive good correlation parameters between the predicted binding affinities (pKi) of the DPP-4 inhibitors and the experimental activity values (pIC50). Based on molecular docking receptor-ligand interactions, pharmacophore generation was carried out in order to identify the binding modes of structurally diverse compounds in the receptor active site. Consideration of the permanence and flexibility of DPP-4 inhibitor complexes by means of molecular dynamics (MD) simulation specified that the inhibitors maintained the binding mode observed in the docking study. The present study helps generate new information for further structural optimization and can influence the development of new DPP-4 inhibitors discoveries in the treatment of type-2 diabetes.

The Vildagliptin Experience - 25 Years Since the Initiation of the Novartis Glucagon-like Peptide-1 Based Therapy Programme and 10 Years Since the First Vildagliptin Registration.

PubMed

Foley, James E; Ahrén, Bo

2017-08-01

The discovery of the incretin hormone glucagon like peptide-1 (GLP-1), and its usefulness in the treatment of type 2 diabetes mellitus (T2DM) followed by the finding that dipeptidyl peptidase-4 (DPP-4) inhibition prevents GLP-1 inactivation, led to the discovery of DPP-728. In 1999, studies with DPP-728 established the first proof-of-concept that DPP-4 inhibition improves glycaemic control in patients with T2DM. Further efforts to improve the binding kinetics of DPP-728 resulted in the discovery of vildagliptin (LAF237). In the last 20 years, a plethora of studies conducted by Novartis in collaboration with external investigators has demonstrated the mechanism of action of vildagliptin and its efficacy as monotherapy and as an add-on therapy for patients with T2DM. The studies establish that vildagliptin is a selective DPP-4 inhibitor that blocks GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) inactivation, thereby prolonging their action, resulting in improved glycaemic control. This review aims to discuss the discovery and development of vildagliptin, with an emphasis on mechanism of action and clinical efficacy.

Localized expression of a dpp/BMP2/4 ortholog in a coral embryo

PubMed Central

Hayward, David C.; Samuel, Gabrielle; Pontynen, Patricia C.; Catmull, Julian; Saint, Robert; Miller, David J.; Ball, Eldon E.

2002-01-01

As the closest outgroup to the Bilateria, the Phylum Cnidaria is likely to be critical to understanding the origins and evolution of body axes. Proteins of the decapentaplegic (DPP)/bone morphogenetic protein (BMP) 2/4 subfamily are central to the specification of the dorsoventral (D/V) axis in bilateral animals, albeit with an axis inversion between arthropods and chordates. We show that a dpp/BMP2/4 ortholog (bmp2/4-Am) is present in the reef-building scleractinian coral, Acropora millepora (Class Anthozoa) and that it is capable of causing phenotypic effects in Drosophila that mimic those of the endogenous dpp gene. We also show that, during coral embryonic development, bmp2/4-Am expression is localized in an ectodermal region adjacent to the blastopore. Thus, a representative of the DPP/BMP2/4 subfamily of ligands was present in the common ancestor of diploblastic and triploblastic animals where it was probably expressed in a localized fashion during development. A localized source of DPP/BMP2/4 may have already been used in axis formation in this ancestor, or it may have provided a means by which an axis could evolve in triploblastic animals. PMID:12048233

COX inhibition excites enteric nerves that affect motility, alkaline secretion, and permeability in rat duodenum.

PubMed

Nylander, O; Hällgren, A; Sababi, M

2001-11-01

In anesthetized rats, the cyclooxygenase (COX) inhibitor indomethacin induces duodenal motility, increases duodenal mucosal alkaline secretion (DMAS), and evokes a transient increase in duodenal paracellular permeability (DPP). To examine whether enteric nerves influence these responses, the duodenum was perfused with lidocaine. Motility was assessed by measuring intraluminal pressure, and DPP was determined as blood-to-lumen clearance of (51)Cr-EDTA. DMAS was assessed by titration. In control animals, few contractions occurred during saline perfusion and lidocaine did not alter this condition. Perfusion with 0.03-0.1% lidocaine did not affect DMAS or DPP whereas 0.3-1% lidocaine reduced DMAS and increased DPP. Indomethacin induced motility and doubled DMAS. Application of 0.03% lidocaine on the duodenal serosa reduced motility and DMAS whereas 0.03% lidocaine applied luminally inhibited DMAS only. Higher concentrations of lidocaine abolished the increase in DMAS and changed the motility pattern to numerous low-amplitude contractions, the latter effect being blocked by iloprost. The lidocaine-induced increases in DPP were markedly higher than in controls. We conclude that indomethacin activates enteric nerves that induce motility, increase DMAS, and decrease DPP.

Transport of 5-aminolevulinic acid by the dipeptide permease in Salmonella typhimurium.

PubMed

Elliott, T

1993-01-01

In a previous search for mutants of Salmonella typhimurium that are defective in heme synthesis, one class that is apparently defective in 5-aminolevulinic acid (ALA) uptake (alu) was found. Here, I describe the characterization of these mutations. The mutations all map to a single locus near 77.5 min on the genetic map, which is transcribed counterclockwise. Nutritional tests, genetic and physical mapping, and partial DNA sequence analysis revealed that alu mutants are defective in a periplasmic binding protein-dependent permease that also transports dipeptides, encoded by the dpp operon. The uptake of labeled ALA is defective in dpp mutants and is markedly increased in a strain that has elevated transcription of the dpp locus. Unlabeled L-leucyl-glycine competes with labeled ALA for uptake. In a strain carrying both a dpp-lac operon fusion and a functional copy of the dpp locus, the expression of beta-galactosidase is not induced by ALA, nor, in a hemL mutant, does expression of dpp change substantially during starvation for ALA. The dipeptide permease displays a relaxed substrate specificity that allows transport of the important nonpeptide nutrient ALA, whose structure is closely related to that of glycyl-glycine.

[Research progress of dipeptidyl peptidase 4 inhibitors on healing of chronic diabetic foot ulcers].

PubMed

Gao, Yunyi; Liang, Yujie; Ran, Xingwu

2018-05-01

To review the effect of dipeptidyl peptidase 4 (DPP-4) inhibitors on the wound healing and its mechanisms in chronic diabetic foot ulcers. The latest literature concerning DPP-4 inhibitors for chronic diabetic foot ulcers was extensively reviewed, as well as the potential benefit and mechanism of DPP-4 inhibitors on wound healing of diabetic foot ulcers was analyzed thoroughly. DPP-4 inhibitors can accelerated the ulcer healing. The mechanisms probably include inhibiting the expression of the matrix metalloproteinase (MMP) and restoring the balance of the wound MMP and the tissue inhibitors of MMP; promoting recruitment of endothelial progenitor cells and augmenting angiogenesis; optimizing extracellular matrix construction and the immune response to persistent hypoxia in chronic diabetes wounds, and so on. At present, clinical researches show that DPP-4 inhibitors may be considered as an adjuvant treatment for chronic diabetic foot ulcers. DPP-4 inhibitors show promise in the local wound healing of chronic diabetic foot ulcers. However, more strictly designed, adequately powered, long-term follow-up, and high-quality randomized control trials are needed to further verify their efficacy and safety for chronic diabetic foot ulcers.

Active phytochemicals of Pueraria tuberosa for DPP-IV inhibition: in silico and experimental approach.

PubMed

Srivastava, Shivani; Shree, Priya; Tripathi, Yamini Bhusan

2017-01-01

We had earlier reported that the extract of Pueraria tuberosa significantly inhibits DPP-IV enzyme, resulting in glucose tolerance response in rats. In this study, we have explored the active phytochemicals responsible for this potential. The results have been validated in both fasting and postprandial states in the plasma of normal rats and also in fasting blood and intestinal homogenates of diabetic models. Pueraria tuberosa water extract (PTWE) was administered to normal Charles Foster rats for 35 days and to diabetic model (65 mg/kg bw) for 10 days. After treatments, oral glucose tolerance test (OGTT) and insulin was done for 90 min, and the changes in the levels of GLP-1, GIP, and DPP-IV activities were monitored in fasting and postprandial states. In the case of the diabetic model, DPP-IV activity was measured in intestinal homogenate and basal insulin in plasma. The components of PTWE were analyzed via HPLC-MS based on their chemical formula, molecular mass, and retention time. Using the molecular docking study, we have selected the top five components having strong binding energy with DPP-IV. The increase in secretion of GLP-1 and GIP was significantly higher in the postprandial state when compared to fasting condition. GLP-1 plasma concentration increased by 5.8 and 2.9 folds and GIP increased by 8.7 and 2.4 folds in PTWE and control rats, respectively. In contrast, the postprandial decrease in DPP-IV specific activities was recorded at 2.3 and 1.4 folds. The response in OGTT and insulin was also consistent with these changes. In comparison to diabetic controls, PTWE-administered rats showed decreased DPP-IV activity in the intestine, leading to enhanced basal insulin concentration. Through molecular docking, we found Puerarone and Robinin to be the most potential phytochemicals of PTWE for DPP-IV inhibition. Binding energy (kcal/mol) and dissociation constant (pM) of Robinin with DPP-IV protein were found to be 7.543 and 2,957,383.75, respectively. For Puerarone, it was 7.376 and 3,920,309, respectively. Thus, this study provides the novel active components that contribute to the DPP-IV inhibitory property of PTWE.

Assessing intravascular volume by difference in pulse pressure in pigs submitted to graded hemorrhage.

PubMed

Pestel, Gunther J; Hiltebrand, Luzius B; Fukui, Kimiko; Cohen, Delphine; Hager, Helmut; Kurz, Andrea M

2006-10-01

We assessed changes in intravascular volume monitored by difference in pulse pressure (dPP%) after stepwise hemorrhage in an experimental pig model. Six pigs (23-25 kg) were anesthetized (isoflurane 1.5 vol%) and mechanically ventilated to keep end-tidal CO2 (etCO2) at 35 mmHg. A PA-catheter and an arterial catheter were placed via femoral access. During and after surgery, animals received lactated Ringer's solution as long as they were considered volume responders (dPP>13%). Then animals were allowed to stabilize from the induction of anesthesia and insertion of catheters for 30 min. After stabilization, baseline measurements were taken. Five percent of blood volume was withdrawn, followed by another 5%, and then in 10%-increments until death from exsanguination occurred. After withdrawal of 5% of blood volume, all pigs were considered volume responders (dPP>13%); dPP rose significantly from 6.1+/-3.3% to 19.4+/-4.2%. The regression analysis of stepwise hemorrhage revealed a linear relation between blood loss (hemorrhage in %) and dPP (y=0.99*x+14; R2=0.7764; P<.0001). In addition, dPP was the only parameter that changed significantly between baseline and a blood loss of 5% (P<0.01), whereas cardiac output, stroke volume, heart rate, MAP, central venous pressure, pulmonary artery occlusion pressure, and systemic vascular resistance, respectively, remained unchanged. We conclude that in an experimental hypovolemic pig model, dPP correlates well with blood loss.

Two Novel Bioactive Peptides from Antarctic Krill with Dual Angiotensin Converting Enzyme and Dipeptidyl Peptidase IV Inhibitory Activities.

PubMed

Ji, Wei; Zhang, Chaohua; Ji, Hongwu

2017-07-01

Inhibition of dipeptidyl peptidase IV (DPP-IV) and angiotensin converting enzyme (ACE) are considered useful in managing 2 often associated conditions: diabetes and hypertension. In this study, corolase PP was used to hydrolyze Antarctic krill protein. The hydrolysate (AKH) was isolated by ultrafiltration and purified by size-exclusion chromatography, ion exchange chromatography and reversed-phase high-performance liquid chromatography (RP-HPLC) sequentially. The in vitro inhibitory activities of all AKHs and several fractions obtained against ACE and DPP-IV were assessed. Two peptides, purified with dual-strength inhibitory activity against ACE and DPP-IV, were identified by TOF-MS/MS. Results indicated that not all fractions exhibited dual inhibitory activities of ACE and DPP-IV. The purified peptide Lys-Val-Glu-Pro-Leu-Pro had half-maximal inhibitory concentrations (IC 50 ) of 0.93±0.05 and 0.73±0.04 mg/mL against ACE and DPP-IV, respectively. The other peptide Pro-Ala-Leu had IC 50 values of 0.64±0.05 and 0.88±0.03 mg/mL against ACE and DPP-IV, respectively. This study firstly reported the sequences of dual bioactive peptides from Antarctic krill proteins, further provided new insights into the bioactive peptides responsible for the ACE and DPP-IV inhibitory activities from the Antarctic krill protein hydrolysate to manage hypertension and diabetes. © 2017 Institute of Food Technologists®.

Inadequate Triglyceride Management Worsens the Durability of Dipeptidyl Peptidase-4 Inhibitor in Subjects with Type 2 Diabetes Mellitus.

PubMed

Shimoda, Masashi; Miyoshi-Takai, Maiko; Irie, Shintaro; Tanabe, Akihito; Obata, Atsushi; Okauchi, Seizo; Hirukawa, Hidenori; Kimura, Tomohiko; Kohara, Kenji; Kamei, Shinji; Mune, Tomoatsu; Kaku, Kohei; Kaneto, Hideaki

2017-01-01

Dipeptidyl peptidase-4 (DPP-4) inhibitors are often used all over the world and exert various beneficial effects including glucose-lowering effect in many subjects with type 2 diabetes. It is poorly understood, however, which factors are closely related with the durability of glucose-lowering effect by DPP-4 inhibitor. In this study, we examined retrospectively which factors could mainly influence the durability of DPP-4 inhibitor. We enrolled 212 participants with type 2 diabetes to whom DPP-4 inhibitor was administered for over 1 year without an addition or increase of other hypoglycemic agents. Age and baseline HbA1c level were significantly higher in the effective group than those in the ineffective group. The effective group had a tendency of smaller amounts of weight change, average total cholesterol, and average triglyceride compared with the ineffective group. Multiple logistic regression analysis showed that average triglyceride and baseline HbA1c were independent predictors associated with the durability of DPP-4 inhibitor. Moreover, an average triglyceride level contributed to the durability of DPP-4 inhibitor in the obese group (BMI ≥ 25 kg/m 2 ) but not in the nonobese group (BMI < 25 kg/m 2 ). These results suggest the importance of strict triglyceride management to maintain the durability of glucose-lowering effect by DPP-4 inhibitor, especially in obese subjects with type 2 diabetes.

30 CFR 250.272 - If a State objects to the DPP's or DOCD's coastal zone consistency certification, what can I do?

Code of Federal Regulations, 2011 CFR

2011-07-01

... coastal zone consistency certification, what can I do? 250.272 Section 250.272 Mineral Resources BUREAU OF... Process for the Dpp Or Docd § 250.272 If a State objects to the DPP's or DOCD's coastal zone consistency certification, what can I do? If an affected State objects to the coastal zone consistency certification...

30 CFR 550.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What hydrogen sulfide (H2S) information must accompany the DPP or DOCD? 550.245 Section 550.245 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.245 What hydrogen sulfide (H2S) information must accompany the DPP or DOCD...

30 CFR 550.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What hydrogen sulfide (H2S) information must accompany the DPP or DOCD? 550.245 Section 550.245 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.245 What hydrogen sulfide (H2S) information must accompany the DPP or DOCD...

30 CFR 550.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What hydrogen sulfide (H2S) information must accompany the DPP or DOCD? 550.245 Section 550.245 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.245 What hydrogen sulfide (H2S) information must accompany the DPP or DOCD...

30 CFR 550.267 - What actions will BOEM take after the DPP or DOCD is deemed submitted?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What actions will BOEM take after the DPP or DOCD is deemed submitted? 550.267 Section 550.267 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Review and Decision Process for the Dpp Or Docd § 550.267 What actions will BOEM take...

30 CFR 550.267 - What actions will BOEM take after the DPP or DOCD is deemed submitted?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What actions will BOEM take after the DPP or DOCD is deemed submitted? 550.267 Section 550.267 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Review and Decision Process for the Dpp Or Docd § 550.267 What actions will BOEM take...

Increased plasma dipeptidyl peptidase-4 activities are associated with high prevalence of subclinical atherosclerosis in Chinese patients with newly diagnosed type 2 diabetes: a cross-sectional study.

PubMed

Zheng, T P; Liu, Y H; Yang, L X; Qin, S H; Liu, H B

2015-10-01

Hyperglycemia, insulin resistance, dislipidemia, oxidative stress and inflammation are well-documented risk factors for subclinical atherosclerosis. Dipeptidyl peptidase-4(DPP4) is a newly identified adipokine related to these risk factors. Hence, we aimed to investigate the association between plasma DPP4 activities and subclinical atherosclerosis in type 2 diabetes. A total of 985 newly diagnosed type 2 diabetic subjects were studied. Plasma DPP4 activity, mannose 6-phosphate receptor (M6P-R), oxidative stress parameters, inflammatory markers and common carotid artery Intima-Media Thickness (c-IMT) were measured in all participants. Participants in the highest quartile of DPP4 activity had higher HbA1c, homeostatic model assessment of insulin resistance(HOMA-IR), triglyceride, low-density lipoprotein cholesterol(LDL-C), oxidized LDL, nitrotyrosine, 8-iso-PGF2a, interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), M6P-R, c-IMT compared with participants in the lowest quartile (all P < 0.001). DPP4 activities were associated positively with HbA1c, HOMA-IR, triglyceride, LDL-C, oxidized LDL, nitrotyrosine, 8-iso-PGF2a, IL-6, hs-CRP, M6P-R and c-IMT (all P < 0.05). The ORs for insulin resistance, dislipidemia, oxidative stress and inflammation were higher with increasing DPP4 quartiles (P < 0.001 for trend). In the highest DPP4 quartile, subclinical atherosclerosis risk was significantly higher (OR 4.97; 95% CI 3.03-8.17) than in the lowest quartile. This association remained strong (2.17; 1.21-3.89) after further controlling for HbA1c, HOMA-IR, triglyceride, oxidized LDL, nitrotyrosine, and IL-6. This study shows that increased DPP4 activities are positively and independently associated with subclinical atherosclerosis in type 2 diabetes. Our findings suggest of potential role of DPP4 in the pathogenesis of subclinical atherosclerosis and in the prevention and management of this disease. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Comparative Effectiveness of DPP-4 Inhibitors Versus Sulfonylurea for the Treatment of Type 2 Diabetes in Routine Clinical Practice: A Retrospective Multicenter Real-World Study.

PubMed

Fadini, Gian Paolo; Bottigliengo, Daniele; D'Angelo, Federica; Cavalot, Franco; Bossi, Antonio Carlo; Zatti, Giancarlo; Baldi, Ileana; Avogaro, Angelo

2018-06-01

DPP-4 inhibitors (DPP4i) and sulfonylureas are popular second-line therapies for type 2 diabetes (T2D), but there is a paucity of real-world studies comparing their effectiveness in routine clinical practice. This was a multicenter retrospective study on diabetes outpatient clinics comparing the effectiveness of DPP4i versus gliclazide extended release. The primary endpoint was change from baseline in HbA1c. Secondary endpoints were changes in fasting plasma glucose, body weight, and systolic blood pressure. Automated software extracted data from the same clinical electronic chart system at all centers. Propensity score matching (PSM) was used to generate comparable cohorts to perform outcome analysis. We included data on 2410 patients starting DPP4i and 1590 patients starting gliclazide (mainly 30-60 mg/day). At baseline, the two groups differed in disease duration, body weight, blood pressure, HbA1c, fasting glucose, HDL cholesterol, triglycerides, liver enzymes, eGFR, prevalence of microangiopathy, and use of metformin. Among DPP4i molecules, no difference in glycemic effectiveness was detected. In matched cohorts (n = 1316/group), patients starting DPP4i, as compared with patients starting gliclazide, experienced greater reductions in HbA1c (- 0.6% versus - 0.4%; p < 0.001), fasting glucose (- 14.1 mg/dl versus - 8.8 mg/dl; p = 0.007), and body weight (- 0.4 kg versus - 0.1 kg; p = 0.006) after an average 6 months follow-up. DPP4i improved glucose control more than gliclazide, especially in patients who had failed with other glucose-lowering medications or were on basal insulin. This large retrospective real-world study shows that, in routine clinical practice, starting a DPP4i allows better glycemic control than starting low-dose gliclazide. The Italian Diabetes Society, with external support from AstraZeneca.

Potential Bioactive Compounds from Seaweed for Diabetes Management.

PubMed

Sharifuddin, Yusrizam; Chin, Yao-Xian; Lim, Phaik-Eem; Phang, Siew-Moi

2015-08-21

Diabetes mellitus is a group of metabolic disorders of the endocrine system characterised by hyperglycaemia. Type II diabetes mellitus (T2DM) constitutes the majority of diabetes cases around the world and are due to unhealthy diet, sedentary lifestyle, as well as rise of obesity in the population, which warrants the search for new preventive and treatment strategies. Improved comprehension of T2DM pathophysiology provided various new agents and approaches against T2DM including via nutritional and lifestyle interventions. Seaweeds are rich in dietary fibres, unsaturated fatty acids, and polyphenolic compounds. Many of these seaweed compositions have been reported to be beneficial to human health including in managing diabetes. In this review, we discussed the diversity of seaweed composition and bioactive compounds which are potentially useful in preventing or managing T2DM by targeting various pharmacologically relevant routes including inhibition of enzymes such as α-glucosidase, α-amylase, lipase, aldose reductase, protein tyrosine phosphatase 1B (PTP1B) and dipeptidyl-peptidase-4 (DPP-4). Other mechanisms of action identified, such as anti-inflammatory, induction of hepatic antioxidant enzymes' activities, stimulation of glucose transport and incretin hormones release, as well as β-cell cytoprotection, were also discussed by taking into consideration numerous in vitro, in vivo, and human studies involving seaweed and seaweed-derived agents.

Potential Bioactive Compounds from Seaweed for Diabetes Management

PubMed Central

Sharifuddin, Yusrizam; Chin, Yao-Xian; Lim, Phaik-Eem; Phang, Siew-Moi

2015-01-01

Diabetes mellitus is a group of metabolic disorders of the endocrine system characterised by hyperglycaemia. Type II diabetes mellitus (T2DM) constitutes the majority of diabetes cases around the world and are due to unhealthy diet, sedentary lifestyle, as well as rise of obesity in the population, which warrants the search for new preventive and treatment strategies. Improved comprehension of T2DM pathophysiology provided various new agents and approaches against T2DM including via nutritional and lifestyle interventions. Seaweeds are rich in dietary fibres, unsaturated fatty acids, and polyphenolic compounds. Many of these seaweed compositions have been reported to be beneficial to human health including in managing diabetes. In this review, we discussed the diversity of seaweed composition and bioactive compounds which are potentially useful in preventing or managing T2DM by targeting various pharmacologically relevant routes including inhibition of enzymes such as α-glucosidase, α-amylase, lipase, aldose reductase, protein tyrosine phosphatase 1B (PTP1B) and dipeptidyl-peptidase-4 (DPP-4). Other mechanisms of action identified, such as anti-inflammatory, induction of hepatic antioxidant enzymes’ activities, stimulation of glucose transport and incretin hormones release, as well as β-cell cytoprotection, were also discussed by taking into consideration numerous in vitro, in vivo, and human studies involving seaweed and seaweed-derived agents. PMID:26308010

Clients' experiences of a community based lifestyle modification program: a qualitative study.

PubMed

Chan, Ruth S M; Lok, Kris Y W; Sea, Mandy M M; Woo, Jean

2009-10-01

There is little information about how clients attending lifestyle modification programs view the outcomes. This qualitative study examined the clients' experience of a community based lifestyle modification program in Hong Kong. Semi-structured interviews were conducted with 25 clients attending the program. Clients perceived the program had positive impacts on their health and nutrition knowledge. They experienced frustration, negative emotion, lack of motivation, and pressure from others during the program. Working environment and lack of healthy food choices in restaurants were the major perceived environmental barriers for lifestyle modification. Clients valued nutritionists' capability of providing professional information and psychological support in the program. Our results suggest that nutritionist's capability of providing quality consultations and patient-centered care are important for empowering clients achieve lifestyle modification.

Reauthorization of Demonstration Partnership Agreements Addressing the Needs of the Poor. Hearing before the Subcommittee on Human Resources of the Committee on Education and Labor. House of Representatives, One Hundred First Congress, First Session.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. House Committee on Education and Labor.

This document presents the record of a hearing on the reauthorization of the Demonstration Partnership Program (DPP), part of the Community Services Block Grant Act. The program offers community action agencies the opportunity to test new methods for reducing dependency and fostering self-sufficiency among the poor. Six agency representatives…

Comparison between SGLT2 inhibitors and DPP4 inhibitors added to insulin therapy in type 2 diabetes: a systematic review with indirect comparison meta-analysis.

PubMed

Min, Se Hee; Yoon, Jeong-Hwa; Hahn, Seokyung; Cho, Young Min

2017-01-01

Both sodium glucose cotransporter 2 (SGLT2) inhibitors and dipeptidyl peptidase-4 (DPP4) inhibitors can be used to treat patients with type 2 diabetes mellitus (T2DM) that is inadequately controlled with insulin therapy, and yet there has been no direct comparison of these two inhibitors. We searched MEDLINE, EMBASE, LILACS, the Cochrane Central Register of Controlled Trials and ClinicalTrials.gov through June 2015. Randomized controlled trials published in English that compare SGLT2 inhibitor plus insulin (SGLT2i/INS) with placebo plus insulin or DPP4 inhibitor plus insulin (DPP4i/INS) with placebo plus insulin in patients with T2DM were selected. Data on the study characteristics, efficacy and safety outcomes were extracted. We compared the efficacy and safety between SGLT2i/INS and DPP4i/INS indirectly with covariates adjustment. Risk of potential bias was assessed. Fourteen eligible randomized controlled trials comprising 6980 patients were included (five SGLT2 inhibitor studies and nine DPP4 inhibitor studies). Covariate-adjusted indirect comparison using meta-regression analyses revealed that SGLT2i/INS achieved greater reduction in HbA 1c [weighted mean difference (WMD) -0.24%, 95% confidence interval (CI) -0.43 to -0.05%], fasting plasma glucose (WMD -18.0 mg/dL, 95% CI -28.5 to -7.6 mg/dL) and body weight (WMD -2.38 kg, 95% CI -3.18 to -1.58 kg) from baseline than DPP4i/INS without increasing the risk of hypoglycaemia (relative risks 1.19, 95% CI 0.78 to 1.82). Sodium glucose cotransporter 2 inhibitors achieved better glycaemic control and greater weight reduction than DPP4 inhibitors without increasing the risk of hypoglycaemia in patients with T2DM that is inadequately controlled with insulin. There has been no direct comparison of SGLT2 inhibitors and DPP4 inhibitors in patients with T2DM inadequately controlled with insulin therapy. In this study, we performed indirect meta-analysis comparing SGLT2 inhibitors and DPP4 inhibitors added to insulin therapy. Without increasing hypoglycaemia, SGLT2 inhibitors showed better glycaemic control and greater weight reduction than DPP4 inhibitors in patients with T2DM inadequately controlled with insulin. The results of the current study could serve as the best available evidence in selecting oral agents to improve glycaemic control in insulin-treated T2DM patients. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The wing and the eye: a parsimonious theory for scaling and growth control?

PubMed

Romanova-Michaelides, Maria; Aguilar-Hidalgo, Daniel; Jülicher, Frank; Gonzalez-Gaitan, Marcos

2015-01-01

How a developing organ grows and patterns to its final shape is an important question in developmental biology. Studies of growth and patterning in the Drosophila wing imaginal disc have identified a key player, the morphogen Decapentaplegic (Dpp). These studies provided insights into our understanding of growth control and scaling: expansion of the Dpp gradient correlated with the growth of the tissue. A recent report on growth of a Drosophila organ other than the wing, the eye imaginal disc, prompts a reconsideration of our models of growth control. Despite striking differences between the two, the Dpp gradient scales with the target tissues of both organs and the growth of both the wing and the eye is controlled by Dpp. The goal of this review is to discuss whether a parsimonious model of scaling and growth control can explain the relationship between the Dpp gradient and growth in these two different developmental systems. © 2015 Wiley Periodicals, Inc.

Sec61α is required for dorsal closure during Drosophila embryogenesis through its regulation of Dpp signaling

PubMed Central

Wang, Xiaochen; Ward, Robert E.

2010-01-01

During dorsal closure in Drosophila, signaling events in the dorsalmost row of epidermal cells (DME cells) direct the migration of lateral epidermal sheets towards the dorsal midline where they fuse to enclose the embryo. A Jun amino-terminal kinase (JNK) cascade in the DME cells induces the expression of Decapentaplegic (Dpp). Dpp signaling then regulates the cytoskeleton in the DME cells and amnioserosa to affect the cell shape changes necessary to complete dorsal closure. We identified a mutation in Sec61α that specifically perturbs dorsal closure. Sec61α encodes the main subunit of the translocon complex for co-translational import of proteins into the ER. JNK signaling is normal in Sec61α mutant embryos, but Dpp signaling is attenuated and the DME cells fail to maintain an actinomyosin cable as epithelial migration fails. Consistent with this model, dorsal closure is rescued in Sec61α mutant embryos by an activated form of the Dpp receptor Thick veins. PMID:20112345

30 CFR 250.281 - What must I do to conduct activities under the approved EP, DPP, or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... approved EP until either: (1) All affected States with approved coastal zone management programs concur, or are conclusively presumed to concur, with the coastal zone consistency certification accompanying your... otherwise necessary in the interest of national security; (3) If an affected State objects to the coastal...

Driving social impact with common global indicators for healthy lifestyle programs: lessons learned.

PubMed

Robinson, Nicole R; Gin, Julia; Kamath-Jha, Shilpa; Infantes, Michel; Hernandez, Ricardo; Alberg-Seberich, Michael; Suri, Devika; Pérez-Escamilla, Rafael

2014-09-01

Partnerships between corporate entities and non-governmental organizations (NGOs) involved in delivering community focused health and well-being programs are becoming increasingly valuable especially in the context of promoting healthy lifestyles around the globe. The Mondelēz International Foundation (MIF) has funded healthy lifestyles community based programs targeting children and youth through partnership with seven global NGOs. To assess collective impact of these programs, it is crucial to identify best practices and common impact indicators that can be measured across programs. MIF therefore organized the Healthy Lifestyles Evaluation Workshop to explore these pertinent questions. Share best practices and identify common impact indicators to measure the success of current and future MIF funded healthy lifestyles programs. Analysis of the Program Impact Pathways (PIPs) and measured output of each of the seven programs. Individual and combined analysis of PIPs of the seven NGO programs led to identification of three critical impact indicators: nutrition knowledge, physical activity, and healthier eating, and also enabled NGOs to identify pathways to improve program delivery among the target population. This workshop enabled MIF and partner NGOs to came together to align on metrics and future engagement approaches for promoting and evaluating community based healthy lifestyles programs.

Shipboard Fluid System Diagnostics Using Non-Intrusive Load Monitoring

DTIC Science & Technology

2007-06-01

brute.s(3).data; tDPP = brute.s(3).time; FL = brute.s(4).data; tFL = brute.s(4).time; RM = brute.s(5).data; tRM = brute.s(5).time; DPF = brute.s...s’, max(tP1), files(n).name)); ylabel(’Power’); axis tight grid on; subplot(4,1,2); plot( tDPP , DPP, tDPF, DPF) ylabel(’DP Gauges’); axis

Safety evaluation of trelagliptin in the treatment of Japanese type 2 diabetes mellitus patients.

PubMed

Kaku, Kohei

2017-11-01

Trelagliptin is a novel, long-acting dipeptidyl peptidase-4 (DPP-4) inhibitor approved for the treatment of type 2 diabetes mellitus (T2DM) in japan. The safety and efficacy of trelagliptin has been evaluated in three published clinical trials to date: one phase II and two phase III studies. As trelagliptin only requires dosing once per week, this new agent has the potential to improve compliance and subsequently, glycaemic control, in patients with T2DM. Areas covered: This article reviews the available safety data for trelagliptin from published clinical trials, and evaluates the published safety profile relative to competitor once-daily and once-weekly DPP-4 inhibitors. Expert opinion: Clinical trial data to date suggest that trelagliptin is a safe and efficacious medication with a similar safety profile to once-daily DPP-4 inhibitors, and to the once-weekly DPP-4 inhibitor, omarigliptin. Trelagliptin is well tolerated when given alone, and in combination with other anti-diabetic medications. An advantage of trelagliptin over existing once-daily DPP-4 inhibitors is the decrease of dosing frequency, rather than once-daily. No specific, serious adverse events have been reported for trelagliptin in published clinical trials, making it an attractive alternative to other DPP-4 inhibitors.

Gestational glucocorticoid exposure disrupts glucose homeostasis that is accompanied by increased endoglin and DPP-4 activity instead of GSK-3 in rats.

PubMed

Badmus, Olufunto O; Michael, Olugbenga S; Rabiu, Saheed; Olatunji, Lawrence A

2018-04-13

Gestational glucocorticoid (GC) treatment has been associated with cardiometabolic disorder (CMD) in offspring's in later life. Elevated dipeptidyl peptidase-4 (DPP-4) activity, endoglin and glycogen synthase kinase-3 (GSK-3) has also been implicated in the development of insulin resistance (IR) and/or vascular inflammation. We aimed to investigate the impact of GC exposure on glucose metabolism and the circulating levels of inflammatory biomarkers, DPP-4 activity and GSK-3 in pregnant rats. Pregnant Wistar rats received either vehicle or dexamethasone (DEX; 0.2 mg/kg; po) between gestational days 14 and 19. Gestational GC exposure resulted in impaired glucose homeostasis that is accompanied with elevated circulating levels of inflammatory biomarkers (endoglin, uric acid, and platelet/lymphocyte ratio), oxidative stress (malondialdehyde), blood viscosity, reduced NO level and increased DPP-4 activity. However, these effects were associated with atherogenic dyslipidemia and reduced GSK-3.We conclude that plasma endoglin, a marker of vascular inflammation, and plasma DPP-4 activity are increased in pregnant rats treated with GC during late gestation. Therefore, glucose deregulation associated with gestational GC exposure is through endoglin-/DPP-4-dependent but GSK-3-independent pathway. Copyright © 2018 Elsevier B.V. All rights reserved.

Diabetes therapies in hemodialysis patients: Dipeptidase-4 inhibitors

PubMed Central

Nakamura, Yuya; Hasegawa, Hitomi; Tsuji, Mayumi; Udaka, Yuko; Mihara, Masatomo; Shimizu, Tatsuo; Inoue, Michiyasu; Goto, Yoshikazu; Gotoh, Hiromichi; Inagaki, Masahiro; Oguchi, Katsuji

2015-01-01

Although several previous studies have been published on the effects of dipeptidase-4 (DPP-4) inhibitors in diabetic hemodialysis (HD) patients, the findings have yet to be reviewed comprehensively. Eyesight failure caused by diabetic retinopathy and aging-related dementia make multiple daily insulin injections difficult for HD patients. Therefore, we reviewed the effects of DPP-4 inhibitors with a focus on oral antidiabetic drugs as a new treatment strategy in HD patients with diabetes. The following 7 DPP-4 inhibitors are available worldwide: sitagliptin, vildagliptin, alogliptin, linagliptin, teneligliptin, anagliptin, and saxagliptin. All of these are administered once daily with dose adjustments in HD patients. Four types of oral antidiabetic drugs can be administered for combination oral therapy with DPP-4 inhibitors, including sulfonylureas, meglitinide, thiazolidinediones, and alpha-glucosidase inhibitor. Nine studies examined the antidiabetic effects in HD patients. Treatments decreased hemoglobin A1c and glycated albumin levels by 0.3% to 1.3% and 1.7% to 4.9%, respectively. The efficacy of DPP-4 inhibitor treatment is high among HD patients, and no patients exhibited significant severe adverse effects such as hypoglycemia and liver dysfunction. DPP-4 inhibitors are key drugs in new treatment strategies for HD patients with diabetes and with limited choices for diabetes treatment. PMID:26131325

Dipeptidyl-peptidase IV inhibitory activity of peptides derived from tuna cooking juice hydrolysates.

PubMed

Huang, Shih-Li; Jao, Chia-Ling; Ho, Kit-Pan; Hsu, Kuo-Chiang

2012-05-01

The in vitro DPP-IV inhibitory activity of isolated peptides from of tuna cooking juice hydrolyzed by Protease XXIII (PR) and orientase (OR) was determined. The results showed that the peptide fractions with the molecular weight over 1,422 Da possessed the greatest DPP-IV inhibitory activity. The amino acid sequences of the three peptides isolated from PR and OR hydrolysates were identified by MALDI-TOF/TOF MS/MS, and they were Pro-Gly-Val-Gly-Gly-Pro-Leu-Gly-Pro-Ile-Gly-Pro-Cys-Tyr-Glu (1412.7 Da), Cys-Ala-Tyr-Gln-Trp-Gln-Arg-Pro-Val-Asp-Arg-Ile-Arg (1690.8 Da) and Pro-Ala-Cys-Gly-Gly-Phe-Try-Ile-Ser-Gly-Arg-Pro-Gly (1304.6 Da), while they showed the dose-dependent inhibition effect of DPP-IV with IC(50) values of 116.1, 78.0 and 96.4 μM, respectively. In vitro simulated gastrointestinal digestion retained or even improved the DPP-IV inhibitory activities of the three peptides. The results suggest that tuna cooking juice would be a good precursor of DPP-IV inhibitor, and the DPP-IV inhibitory peptides can successfully passed through the digestive tract. Copyright © 2012 Elsevier Inc. All rights reserved.

Discovery of DPP IV inhibitors by pharmacophore modeling and QSAR analysis followed by in silico screening.

PubMed

Al-Masri, Ihab M; Mohammad, Mohammad K; Taha, Mutasem O

2008-11-01

Dipeptidyl peptidase IV (DPP IV) deactivates the natural hypoglycemic incretin hormones. Inhibition of this enzyme should restore glucose homeostasis in diabetic patients making it an attractive target for the development of new antidiabetic drugs. With this in mind, the pharmacophoric space of DPP IV was explored using a set of 358 known inhibitors. Thereafter, genetic algorithm and multiple linear regression analysis were employed to select an optimal combination of pharmacophoric models and physicochemical descriptors that yield selfconsistent and predictive quantitative structure-activity relationships (QSAR) (r(2) (287)=0.74, F-statistic=44.5, r(2) (BS)=0.74, r(2) (LOO)=0.69, r(2) (PRESS) against 71 external testing inhibitors=0.51). Two orthogonal pharmacophores (of cross-correlation r(2)=0.23) emerged in the QSAR equation suggesting the existence of at least two distinct binding modes accessible to ligands within the DPP IV binding pocket. Docking experiments supported the binding modes suggested by QSAR/pharmacophore analyses. The validity of the QSAR equation and the associated pharmacophore models were established by the identification of new low-micromolar anti-DPP IV leads retrieved by in silico screening. One of our interesting potent anti-DPP IV hits is the fluoroquinolone gemifloxacin (IC(50)=1.12 muM). The fact that gemifloxacin was recently reported to potently inhibit the prodiabetic target glycogen synthase kinase 3beta (GSK-3beta) suggests that gemifloxacin is an excellent lead for the development of novel dual antidiabetic inhibitors against DPP IV and GSK-3beta.

Utilisation of the isobole methodology to study dietary peptide-drug and peptide-peptide interactive effects on dipeptidyl peptidase IV (DPP-IV) inhibition.

PubMed

Nongonierma, Alice B; FitzGerald, Richard J

2015-01-01

Inhibition of dipeptidyl peptidase-IV (DPP-IV) is used as a means to regulate post-prandial serum glucose in type 2 diabetics. The effect of drug (Sitagliptin®)/peptide and binary peptide mixtures on DPP-IV inhibition was studied using an isobole approach. Five peptides (Ile-Pro-Ile-Gln-Tyr, Trp-Lys, Trp-Pro, Trp-Arg and Trp-Leu), having DPP-IV half maximum inhibitory concentration values (IC₅₀)<60 μM and reported to act through different inhibition mechanisms, were investigated. The dose response relationship of Sitagliptin : peptide (1:0, 0:1, 1:852, 1:426 and 1:1704 on a molar basis) and binary Ile-Pro-Ile-Gln-Tyr : peptide (1:0, 0:1, 1:1, 1:2 and 2:1 on a molar basis) mixtures for DPP-IV inhibition was characterised. Isobolographic analysis showed, in most instances, an additive effect on DPP-IV inhibition. However, a synergistic effect was observed with two Sitagliptin:Ile-Pro-Ile-Gln-Tyr (1:426 and 1:852) mixtures and an antagonistic effect was seen with one Sitagliptin : Trp-Pro (1:852) mixture, and three binary peptide mixtures (Ile-Pro-Ile-Gln-Tyr : Trp-Lys (1:1 and 2:1) and Ile-Pro-Ile-Gln-Tyr:Trp-Leu (1:2)). The results show that Sitagliptin and food protein-derived peptides can interact, thereby enhancing overall DPP-IV inhibition. Combination of Sitagliptin with food protein-derived peptides may help in reducing drug dosage and possible associated side-effects.

Novel N-substituted aminobenzamide scaffold derivatives targeting the dipeptidyl peptidase-IV enzyme.

PubMed

Al-Balas, Qosay A; Sowaileh, Munia F; Hassan, Mohammad A; Qandil, Amjad M; Alzoubi, Karem H; Mhaidat, Nizar M; Almaaytah, Ammar M; Khabour, Omar F

2014-01-01

The dipeptidyl peptidase-IV (DPP-IV) enzyme is considered a pivotal target for controlling normal blood sugar levels in the body. Incretins secreted in response to ingestion of meals enhance insulin release to the blood, and DPP-IV inactivates these incretins within a short period and stops their action. Inhibition of this enzyme escalates the action of incretins and induces more insulin to achieve better glucose control in diabetic patients. Thus, inhibition of this enzyme will lead to better control of blood sugar levels. In this study, computer-aided drug design was used to help establish a novel N-substituted aminobenzamide scaffold as a potential inhibitor of DPP-IV. CDOCKER software available from Discovery Studio 3.5 was used to evaluate a series of designed compounds and assess their mode of binding to the active site of the DPP-IV enzyme. The designed compounds were synthesized and tested against a DPP-IV enzyme kit provided by Enzo Life Sciences. The synthesized compounds were characterized using proton and carbon nuclear magnetic resonance, mass spectrometry, infrared spectroscopy, and determination of melting point. Sixty-nine novel compounds having an N-aminobenzamide scaffold were prepared, with full characterization. Ten of these compounds showed more in vitro activity against DPP-IV than the reference compounds, with the most active compounds scoring 38% activity at 100 μM concentration. The N-aminobenzamide scaffold was shown in this study to be a valid scaffold for inhibiting the DPP-IV enzyme. Continuing work could unravel more active compounds possessing the same scaffold.

Therapeutic Potential of Date Palm Pollen for Testicular Dysfunction Induced by Thyroid Disorders in Male Rats.

PubMed

El-Kashlan, Akram M; Nooh, Mohammed M; Hassan, Wafaa A; Rizk, Sherine M

2015-01-01

Hyper- or hypothyroidism can impair testicular function leading to infertility. The present study was designed to examine the protective effect of date palm pollen (DPP) extract on thyroid disorder-induced testicular dysfunction. Rats were divided into six groups. Group I was normal control. Group II received oral DPP extract (150 mg kg(-1)), group III (hyperthyroid group) received intraperitoneal injection of L-thyroxine (L-T4, 300 μg kg(-1); i.p.), group IV received L-T4 plus DPP extract, group V (hypothyroid group) received propylthiouracil (PTU, 10 mg kg(-1); i.p.) and group VI received PTU plus DPP extract. All treatments were given every day for 56 days. L-T4 or PTU lowered genital sex organs weight, sperm count and motility, serum levels of luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone (T), testicular function markers and activities of testicular 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β-HSD). Moreover, L-T4 or PTU increased estradiol (E2) serum level, testicular oxidative stress, DNA damage and apoptotic markers. Morphometric and histopathologic studies backed these observations. Treatment with DPP extract prevented LT4- or PTU induced changes. In addition, supplementation of DPP extract to normal rats augmented sperm count and motility, serum levels of LH, T and E2 paralleled with increased activities of 3β-HSD and 17β-HSD as well as testicular antioxidant status. These results provide evidence that DPP extract may have potential protective effects on testicular dysfunction induced by altered thyroid hormones.

Therapeutic Potential of Date Palm Pollen for Testicular Dysfunction Induced by Thyroid Disorders in Male Rats

PubMed Central

El-Kashlan, Akram M.; Nooh, Mohammed M.; Hassan, Wafaa A.; Rizk, Sherine M.

2015-01-01

Hyper- or hypothyroidism can impair testicular function leading to infertility. The present study was designed to examine the protective effect of date palm pollen (DPP) extract on thyroid disorder-induced testicular dysfunction. Rats were divided into six groups. Group I was normal control. Group II received oral DPP extract (150 mg kg-1), group III (hyperthyroid group) received intraperitoneal injection of L-thyroxine (L-T4, 300μg kg-1; i.p.), group IV received L-T4 plus DPP extract, group V (hypothyroid group) received propylthiouracil (PTU, 10 mg kg-1; i.p.) and group VI received PTU plus DPP extract. All treatments were given every day for 56 days. L-T4 or PTU lowered genital sex organs weight, sperm count and motility, serum levels of luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone (T), testicular function markers and activities of testicular 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β-HSD). Moreover, L-T4 or PTU increased estradiol (E2) serum level, testicular oxidative stress, DNA damage and apoptotic markers. Morphometric and histopathologic studies backed these observations. Treatment with DPP extract prevented LT4- or PTU induced changes. In addition, supplementation of DPP extract to normal rats augmented sperm count and motility, serum levels of LH, T and E2 paralleled with increased activities of 3β-HSD and 17β-HSD as well as testicular antioxidant status. These results provide evidence that DPP extract may have potential protective effects on testicular dysfunction induced by altered thyroid hormones. PMID:26425844

Tetra- and Heptametallic Ru(II),Rh(III) Supramolecular Hydrogen Production Photocatalysts

DOE PAGES

Manbeck, Gerald F.; Fujita, Etsuko; Brewer, Karen J.

2017-06-01

Supramolecular mixed metal complexes combining the trimetallic chromophore [{(bpy) 2Ru(dpp)} 2Ru(dpp)] 6+ (Ru 3) with [Rh(bpy)Cl 2] + or [RhCl 2] + catalytic fragments to form [{(bpy) 2Ru(dpp)} 2Ru(dpp)RhCl 2(bpy)](PF 6) 7 (Ru 3Rh) or [{(bpy) 2Ru(dpp)} 2Ru(dpp)] 2RhCl 2(PF 6) 13 (Ru 3RhRu 3) (bpy = 2,2'-bipyridine and dpp = 2,3-bis(2-pyridyl)pyrazine) catalyze the photochemical reduction of protons to H 2. This first example of a heptametallic Ru,Rh photocatalyst produces over 300 turnovers of H 2 upon photolysis of a solution of acetonitrile, water, triflic acid, and N,N-dimethylaniline as an electron donor. Conversely, the tetrametallic Ru 3Rh produces only 40more » turnovers of H 2 due to differences in the excited state properties and nature of the catalysts upon reduction as ascertained from electrochemical data, transient absorption spectroscopy, and flash-quench experiments. And while the lowest unoccupied molecular orbital of Ru 3Rh is localized on a bridging ligand, it is Rh-centered in Ru 3RhRu 3 facilitating electron collection at Rh in the excited state and reductively quenched state. The Ru → Rh charge separated state of Ru 3RhRu 3 is endergonic with respect to the emissive Ru → dpp 3MLCT excited and cannot be formed by static electron transfer quenching of the 3MLCT state. Instead, a mechanism of subnanosecond charge separation from high lying states is proposed. Multiple reductions of Ru 3 and Ru 3Rh using sodium amalgam were carried out to compare UV–vis absorption spectra of reduced species and to evaluate the stability of highly reduced complexes. Furthermore, the Ru 3 and Ru 3Rh can be reduced by 10 and 13 electrons, respectively, to final states with all bridging ligands doubly reduced and all bpy ligands singly reduced.« less

(2S,4S)-4-Fluoro-1-{[(2-hydroxy-1,1-dimethylethyl)amino]acetyl}-pyrrolidine-2-carbonitrile monobenzenesulfonate (TS-021) is a selective and reversible dipeptidyl peptidase IV inhibitor.

PubMed

Tajima, Atsushi; Yamamoto, Koji; Kozakai, Akinori; Okumura-Kitajima, Lisa; Mita, Yasuo; Kitano, Kiyokazu; Jingu, Shigeji; Nakaike, Shiro

2011-03-25

The incretin hormone glucagon-like peptide-1 (GLP-1) has significant roles in the regulation of postprandial glucose metabolism, and the active form of GLP-1 is rapidly degraded by dipeptidyl peptidase (DPP)-IV. Therefore, DPP-IV inhibition is a promising approach for the treatment of type 2 diabetes. In the present study, we investigated the character of a DPP-IV inhibitor, TS-021, (2S, 4S)-4-fluoro-1-{[(2-hydroxy-1,1-dimethylethyl)amino]acetyl}-pyrrolidine-2-carbonitrile monobenzenesulfonate both in vitro and in vivo. TS-021 inhibits DPP-IV activity in human plasma with an IC(50) value of 5.34nM. In kinetics experiments, TS-021 had a relatively higher dissociation rate constant, with a k(off) value of 1.09×10(-3)s, despite exhibiting a potent human plasma DPP-IV inhibition activity with a K(i) value of 4.96nM. TS-021 exhibited significant inhibition selectivity against DPP-8 (>600 fold), DPP-9 (>1200 fold) and other peptidases examined (>15,000 fold). In normal rats, dogs and monkeys, a single oral dose of TS-021 exhibited favorable pharmacokinetic profiles. In Zucker fatty (fa/fa) rats, a rat model of obesity and impaired glucose tolerance, the oral administration of TS-021 resulted in the suppression of plasma DPP-IV activity and an increase in the active form of GLP-1. Furthermore, TS-021 exhibited a significant improvement in glucose tolerance by increasing the plasma insulin level during oral glucose tolerance tests at doses of 0.02-0.5mg/kg. These results suggest that TS-021 is a selective and reversible dipeptidyl peptidase IV inhibitor and has excellent characteristics as an oral anti-diabetic agent for postprandial hyperglycemia in patients with impaired glucose tolerance or type 2 diabetes. Copyright © 2011 Elsevier B.V. All rights reserved.

Efficacy of dipeptidyl-peptidase-4 inhibitors and impact on β-cell function in Asian and Caucasian type 2 diabetes mellitus patients: A meta-analysis.

PubMed

Cai, Xiaoling; Han, Xueyao; Luo, Yingying; Ji, Linong

2015-05-01

This work aimed to compare the efficacy of dipeptidyl peptidase-IV (DPP-4) inhibitors and their impact on β-cell function in Asian and Caucasian patients with type 2 diabetes mellitus. Databases were systematically searched and qualifying studies that compared DPP-4 inhibitors with other antidiabetic medications in type 2 diabetes were included. A total of 68 studies were included in the meta-analysis. Comparison of DPP-4 inhibitors with placebo in Asian patients showed a decrease in glycosylated hemoglobin (HbA1c ) favoring DPP-4 inhibitors (weighted mean difference [WMD], -0.81%; 95% confidence interval [CI], -0.95% to -0.68%; P < 0.001). Comparison of HbA1c changes between Asian and Caucasian patients showed a significant between-group difference of -0.18% (95% CI, -0.32% to -0.04%; P = 0.011) when compared with placebo. In Asian patients, the homeostatic model assessment for β-cell function (HOMA-β) was increased with DPP-4 inhibitors compared with placebo (WMD, 7.90; 95% CI, 4.29 to 11.51; P < 0.001), although to a lesser extent in Caucasian patients. Comparisons between Asian and Caucasian patients showed a significant between-group difference of -4.97 (95% CI, -9.86 to -0.09; P = 0.046) compared with placebo. Body weight increase with DPP-4 inhibitors compared with placebo was comparable in Asian and Caucasian studies (WMD, 0.37 kg and 0.45 kg and 95% CI, 0.04-0.69 and 0.27-0.62, respectively). The glucose-lowering efficacy of DPP-4 inhibitors was greater in Asian patients than in Caucasian patients, although the effect on β-cell function was inferior in Asian patients. The effect of DPP-4 inhibitors on insulin resistance and body weight in Asian patients was comparable with that observed in Caucasian patients. © 2014 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Profiling inflammatory biomarkers in cervico-vaginal mucus (CVM) postpartum: Potential early indicators of bovine clinical endometritis?

PubMed

Adnane, Mounir; Chapwanya, Aspinas; Kaidi, Rachid; Meade, Kieran G; O'Farrelly, Cliona

2017-11-01

Endometritis significantly impacts fertility and milk yield, thus reducing profitability of the dairy production. In cows that develop endometritis, normal postpartum endometrial inflammation is dysregulated. Here, we propose that endometrial inflammation is reflected in cervico-vaginal mucus (CVM) which could therefore be used as a prognostic tool. CVM was collected from 20 dairy cows (10 with clinical endometritis and 10 healthy) 7 and 21 days postpartum (DPP). Polymorphonuclear (PMN), mononuclear leukocyte and epithelial cells were counted, total protein levels were estimated and levels of IL-1β, IL-6, IL-8, serum amyloid A (SAA), haptoglobin (Hp) and C5b were analyzed by ELISA in CVM. PMN were consistently high in CVM from 7 to 21 DPP, but were higher in CVM from cows with clinical endometritis 21 DPP compared with healthy cows. In contrast, there were more epithelial cells in healthy cows 21 DPP than in clinical endometritis animals. Total protein levels decreased significantly in CVM from healthy cows between days 7 and 21 postpartum. All inflammatory biomarkers except C5b, remained high in cows with clinical endometritis from 7 to 21 DPP, indicating sustained and chronic endometrial inflammation. IL1, IL-6, IL-8 and Hp levels were higher in CVM from cows with clinical endometritis compared to healthy cows 21 DPP. Interestingly IL-1β levels were raised in CVM from clinical endometritis but not in healthy cows 7 DPP suggesting that early measurement of IL-1β levels might provide a useful predictive marker of clinical endometritis. In contrast, SAA and C5b levels were increased in healthy cows 21 DPP, compared to cows with clinical endometritis suggesting that these acute phase proteins might have an anti-inflammatory role. Our results show that CVM is convenient for profiling disease-associated changes in key inflammatory molecules postpartum and reaffirms that sustained inflammation is a key feature of clinical endometritis in the dairy cow. Copyright © 2017. Published by Elsevier Inc.

Dipeptidyl Peptidase-4 Inhibitor Use is Associated with Decreased Risk of Fracture in Patients with Type 2 Diabetes: A Population-Based Cohort Study.

PubMed

Hou, Wen-Hsuan; Chang, Kai-Cheng; Li, Chung-Yi; Ou, Huang-Tz

2018-05-16

To investigate the putative link between dipeptidyl peptidase-4 inhibitor (DPP-4i) use and the risk of fracture in patients with type 2 diabetes. This propensity-score-matched population-based cohort study was performed between 2009 and 2013 on patients with type 2 diabetes who were stable metformin users. A total of 3,996 patients with type 2 diabetes used DPP-4i as a second-line antidiabetic drug. The same number of matched non-DPP-4i users were followed up until fracture occurrence, health insurance policy termination, or the end of 2013. The incidence rates of overall and cause-specific fractures were estimated based on the Poisson assumption. A multiple Cox proportional hazard model was used to estimate the covariate-adjusted hazard ratio (HR) and 95% confidence interval (CI) to determine the association between DPP-4i use and overall and cause-specific fractures stratified by age and sex. Over a maximum follow-up period of 5 years, 340 DPP-4i users and 419 non-DPP-4i users were newly diagnosed with fractures, yielding incidence rates of 28.03 and 32.04 per 1,000 people per year, respectively. The Cox proportional hazard model revealed that DPP-4i use significantly reduced the risk of all-cause fractures and upper extremity fractures, with adjusted HRs of 0.86 (95% CI: 0.74-0.99) and 0.75 (95% CI: 0.59-0.95), respectively. The aforementioned associations of DDP-4i use with fracture were sustained across sex and age stratifications. The results of this study supported the premise that DPP-4i usage is associated with a reduced risk of all-cause fractures and upper extremity fractures in patients with type 2 diabetes. This article is protected by copyright. All rights reserved.

Solar H2 evolution in water with modified diketopyrrolopyrrole dyes immobilised on molecular Co and Ni catalyst-TiO2 hybrids.

PubMed

Warnan, Julien; Willkomm, Janina; Ng, Jamues N; Godin, Robert; Prantl, Sebastian; Durrant, James R; Reisner, Erwin

2017-04-01

A series of diketopyrrolopyrrole (DPP) dyes with a terminal phosphonic acid group for attachment to metal oxide surfaces were synthesised and the effect of side chain modification on their properties investigated. The organic photosensitisers feature strong visible light absorption ( λ = 400 to 575 nm) and electrochemical and fluorescence studies revealed that the excited state of all dyes provides sufficient driving force for electron injection into the TiO 2 conduction band. The performance of the DPP chromophores attached to TiO 2 nanoparticles for photocatalytic H 2 evolution with co-immobilised molecular Co and Ni catalysts was subsequently studied, resulting in solar fuel generation with a dye-sensitised semiconductor nanoparticle system suspended in water without precious metal components. The performance of the DPP dyes in photocatalysis did not only depend on electronic parameters, but also on properties of the side chain such as polarity, steric hinderance and hydrophobicity as well as the specific experimental conditions and the nature of the sacrificial electron donor. In an aqueous pH 4.5 ascorbic acid solution with a phosphonated DuBois-type Ni catalyst, a DPP-based turnover number (TON DPP ) of up to 205 was obtained during UV-free simulated solar light irradiation (100 mW cm -2 , AM 1.5G, λ > 420 nm) after 1 day. DPP-sensitised TiO 2 nanoparticles were also successfully used in combination with a hydrogenase or platinum instead of the synthetic H 2 evolution catalysts and the platinum-based system achieved a TON DPP of up to 2660, which significantly outperforms an analogous system using a phosphonated Ru tris(bipyridine) dye (TON Ru = 431). Finally, transient absorption spectroscopy was performed to study interfacial recombination and dye regeneration kinetics revealing that the different performances of the DPP dyes are most likely dictated by the different regeneration efficiencies of the oxidised chromophores.

Lowered serum dipeptidyl peptidase IV activity is associated with depressive symptoms and cytokine production in cancer patients receiving interleukin-2-based immunotherapy.

PubMed

Maes, M; Capuron, L; Ravaud, A; Gualde, N; Bosmans, E; Egyed, B; Dantzer, R; Neveu, P J

2001-02-01

There is some evidence that treatment with interleukin-2 (IL-2) and interferon-alpha (IFNalpha) frequently induces depressive symptoms and activation of the inflammatory response system (IRS). There is evidence that major depression is accompanied by lowered serum activity of dipeptidyl peptidase IV (DPP IV; EC 3.4.14.5), a membrane-bound serine protease which catalyses the cleavage of some cytokines and neuro-active peptides and which modulates T cell activation and the production of cytokines, such as IL-2. This study was carried out to examine the effects of immunochemotherapy with IL-2 and IFNalpha, alone and together, in cancer patients on serum DPP IV activity in relation to changes in depressive symptoms and the IRS. The Montgomery and Asberg Rating Scale (MADRS), serum DPP IV activity, and the serum IL-6, and IL-2 receptor (IL-2R) concentrations were measured in 26 patients with metastatic cancers before and three and five days after treatment with IL-2 and IFNalpha, alone or together. Treatment with IL-2 with or without IFNalpha significantly suppressed serum DPP IV activity. The MADRS scores were significantly elevated by treatment with IL-2 with or without IFNalpha, but not IFNalpha alone. The immunochemotherapy-induced decreases in serum DPP IV were significantly and inversely correlated with the increases in the MADRS. Treatment with IL-2 alone or combined with IFNalpha also elevated serum IL-6 and IL-2R. There were significant and inverse correlations between the immuchemotherapy-induced decreases in serum DPP IV and the elevations in serum IL-6 or IL-2R. In conclusion, treatment with IL-2/IFNalpha decreases serum DPP IV activity within 3-5 days and the immunochemotherapy-induced decreases in serum DPP IV activity are significantly and inversely related to treatment-induced increases in severity of depression and signs of activation of the IRS.

Use of side-chain for rational design of n-type diketopyrrolopyrrole-based conjugated polymers: what did we find out?

PubMed

Kanimozhi, Catherine; Yaacobi-Gross, Nir; Burnett, Edmund K; Briseno, Alejandro L; Anthopoulos, Thomas D; Salzner, Ulrike; Patil, Satish

2014-08-28

The primary role of substituted side chains in organic semiconductors is to increase their solubility in common organic solvents. In the recent past, many literature reports have suggested that the side chains play a critical role in molecular packing and strongly impact the charge transport properties of conjugated polymers. In this work, we have investigated the influence of side-chains on the charge transport behavior of a novel class of diketopyrrolopyrrole (DPP) based alternating copolymers. To investigate the role of side-chains, we prepared four diketopyrrolopyrrole-diketopyrrolopyrrole (DPP-DPP) conjugated polymers with varied side-chains and carried out a systematic study of thin film microstructure and charge transport properties in polymer thin-film transistors (PTFTs). Combining results obtained from grazing incidence X-ray diffraction (GIXD) and charge transport properties in PTFTs, we conclude side-chains have a strong influence on molecular packing, thin film microstructure, and the charge carrier mobility of DPP-DPP copolymers. However, the influence of side-chains on optical properties was moderate. The preferential "edge-on" packing and dominant n-channel behavior with exceptionally high field-effect electron mobility values of >1 cm(2) V(-1) s(-1) were observed by incorporating hydrophilic (triethylene glycol) and hydrophobic side-chains of alternate DPP units. In contrast, moderate electron and hole mobilities were observed by incorporation of branched hydrophobic side-chains. This work clearly demonstrates that the subtle balance between hydrophobicity and hydrophilicity induced by side-chains is a powerful strategy to alter the molecular packing and improve the ambipolar charge transport properties in DPP-DPP based conjugated polymers. Theoretical analysis supports the conclusion that the side-chains influence polymer properties through morphology changes, as there is no effect on the electronic properties in the gas phase. The exceptional electron mobility is at least partially a result of the strong intramolecular conjugation of the donor and acceptor as evidenced by the unusually wide conduction band of the polymer.

The serum level of soluble CD26/dipeptidyl peptidase 4 increases in response to acute hyperglycemia after an oral glucose load in healthy subjects: association with high-molecular weight adiponectin and hepatic enzymes.

PubMed

Aso, Yoshimasa; Terasawa, Tomoko; Kato, Kanako; Jojima, Teruo; Suzuki, Kunihiro; Iijima, Toshie; Kawagoe, Yoshiaki; Mikami, Shigeru; Kubota, Yoshiro; Inukai, Toshihiko; Kasai, Kikuo

2013-11-01

A soluble form of CD26/dipeptidyl peptidase 4 (sCD26/DPP4) is found in serum and it has DPP4 enzymatic activity. We investigated whether the serum level of sCD26/DPP4 was influenced by the oral glucose tolerance test (OGTT) in healthy subjects. The serum sCD26/DPP4 level increased significantly from 824.5 ng/mL (interquartile range, from 699.0 to 1050 ng/mL) at baseline to a peak of 985.0 ng/mL (interquartile range, from 796.5 to 1215 ng/mL) during the OGTT (P < 0.0001). The peak sCD26/DPP4 level correlated positively with the baseline age and body mass index, and fasting plasma glucose (FPG), homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides (TG), alanine aminotransferase, and γ-glutamyl transpeptidase (GGT) levels whereas it correlated negatively with high-density lipoprotein (HDL) cholesterol and the serum levels of total and high-molecular weight (HMW) adiponectin. Stepwise regression analysis was done with forward selection of variables, including age, FPG, HOMA-IR, TG, HDL cholesterol, uric acid, GGT, C-reactive protein, and HMW adiponectin. In a model that explained 57.5% of the variation of the peak sCD26/DPP4 level, GGT (β = 0.382, P = 0.007) and HOMA-IR (β = 0.307, P = 0.034) were independent determinants of the peak serum level of sCD26/DPP4. Serum HMW adiponectin decreased significantly from 4.43 μg/mL (interquartile range, from 2.80 to 6.65 μg/mL) at baseline to 4.17 μg/mL (interquartile range, from 2.48 to 6.96 μg/mL) 120 minutes after the oral glucose load (P < 0.0001). The baseline serum level of sCD26/DPP4 showed a significant negative correlation with the percent change of HMW adiponectin during the OGTT. In conclusion, the serum level of sCD26/DPP4 increased acutely after an oral glucose load in apparently healthy subjects. The abrupt increase of serum sCD26/DPP4 after a glucose load may be a marker of insulin resistance that could come from liver or muscle. Copyright © 2013 Mosby, Inc. All rights reserved.

Usage of an online healthy lifestyle program by pregnant women attending midwifery practices in Amsterdam.

PubMed

van Zutphen, Moniek; Milder, Ivon E; Bemelmans, Wanda J

2008-06-01

To determine reach, attrition and program engagement and their associations with user characteristics for an online healthy lifestyle program for pregnant women. From March to August 2006, 1382 pregnant women visiting 20 midwifery practices in Amsterdam were invited to enroll in a healthy lifestyle program through registration on the program website (at home). User characteristics were self-reported upon enrollment, while program use was objectively monitored until January 2007. Seventeen percent (n=238) of the women who received information from their midwife enrolled. Most women were highly educated (68%) and already had a healthy lifestyle. About half of them (52%) continued to use the program throughout their pregnancy. Less lower than higher educated women continued using the program (45% vs. 63%, p=0.02). When e-mails were opened almost all lifestyle topics were accessed (85%), but links to related websites were used less often (12%). The healthy lifestyle program did not reach a substantial proportion of the target population. Only 9% of those invited continued to use the program throughout their pregnancies. In addition to that there was selective enrollment and selective attrition. This research confirms that disadvantaged women, who need the intervention most, are least easily reached.

Type 2 diabetes patients’ preferences and willingness to pay for lifestyle programs: a discrete choice experiment

PubMed Central

2013-01-01

Background Participation rates of lifestyle programs among type 2 diabetes mellitus (T2DM) patients are less than optimal around the globe. Whereas research shows notable delays in the development of the disease among lifestyle program participants. Very little is known about the relative importance of barriers for participation as well as the willingness of T2DM patients to pay for participation in such programs. The aim of this study was to identify the preferences of T2DM patients with regard to lifestyle programs and to calculate participants’ willingness to pay (WTP) as well as to estimate the potential participation rates of lifestyle programs. Methods A Discrete Choice Experiment (DCE) questionnaire assessing five different lifestyle program attributes was distributed among 1250 Dutch adults aged 35–65 years with T2DM, 391 questionnaires (31%) were returned and included in the analysis. The relative importance of the program attributes (i.e., meal plan, physical activity (PA) schedule, consultation structure, expected program outcome and out-of-pocket costs) was determined using panel-mixed logit models. Based on the retrieved attribute estimates, patients’ WTP and potential participation rates were determined. Results The out-of-pocket costs (β = −0.75, P < .001), consultation structure (β = −0.46, P < .001) and expected outcome (β = 0.72, P < .001) were the most important factors for respondents when deciding whether to participate in a lifestyle program. Respondents were willing to pay €128 per year for individual instead of group consultation and €97 per year for 10 kilograms anticipated weight loss. Potential participation rates for different lifestyle-program scenarios ranged between 48.5% and 62.4%. Conclusions When deciding whether to participate in a lifestyle program, T2DM patients are mostly driven by low levels of out-of-pocket costs. Thereafter, they prefer individual consultation and high levels of anticipated outcomes with respect to weight loss. PMID:24289831

Human dipeptidyl peptidase III acts as a post-proline-cleaving enzyme on endomorphins.

PubMed

Barsun, Marina; Jajcanin, Nina; Vukelić, Bojana; Spoljarić, Jasminka; Abramić, Marija

2007-03-01

Dipeptidyl peptidase III (DPP III) is a zinc exopeptidase with an implied role in the mammalian pain-modulatory system owing to its high affinity for enkephalins and localisation in the superficial laminae of the spinal cord dorsal horn. Our study revealed that this human enzyme hydrolyses opioid peptides belonging to three new groups, endomorphins, hemorphins and exorphins. The enzymatic hydrolysis products of endomorphin-1 were separated and quantified by capillary electrophoresis and the kinetic parameters were determined for human DPP III and rat DPP IV. Both peptidases cleave endomorphin-1 at comparable rates, with liberation of the N-terminal Tyr-Pro. This is the first evidence of DPP III acting as an endomorphin-cleaving enzyme.

[Arterial pressure curve and fluid status].

PubMed

Pestel, G; Fukui, K

2009-04-01

Fluid optimization is a major contributor to improved outcome in patients. Unfortunately, anesthesiologists are often in doubt whether an additional fluid bolus will improve the hemodynamics of the patient or not as excess fluid may even jeopardize the condition. This article discusses physiological concepts of liberal versus restrictive fluid management followed by a discussion on the respective capabilities of various monitors to predict fluid responsiveness. The parameter difference in pulse pressure (dPP), derived from heart-lung interaction in mechanically ventilated patients is discussed in detail. The dPP cutoff value of 13% to predict fluid responsiveness is presented together with several assessment techniques of dPP. Finally, confounding variables on dPP measurements, such as ventilation parameters, pneumoperitoneum and use of norepinephrine are also mentioned.

Comparisons of the efficacy of glucose control, lipid profile, and β-cell function between DPP-4 inhibitors and AGI treatment in type 2 diabetes patients: a meta-analysis.

PubMed

Cai, Xiaoling; Yang, Wenjia; Zhou, Lingli; Zhang, Simin; Han, Xueyao; Ji, Linong

2015-12-01

The aim of this study is to compare the efficacy of dipeptidyl peptidase-4 (DPP-4) inhibitor treatment with α-glucosidase inhibitor (AGI) treatment in patients with type 2 diabetes through a meta-analysis. Studies were identified by a literature search of Medline, Embase, and others from the time that recording commenced until December 2014. The meta-analysis was performed by computing the weighted mean difference (WMD) and 95 % confidence interval (CI) for a change from baseline to the study endpoint for DPP-4 inhibitors versus AGIs. Nine randomized controlled trial were judged to be appropriate for inclusion in the meta-analysis. One thousand and forty-six patients were treated with a DPP-4 inhibitor, while 929 patients were treated with AGI treatment; the groups had a comparable baseline body mass index of 25.5 ± 1.3 kg/m(2) and mean baseline HbA1c of 7.83 ± 0.53 %. Treatment with DPP-4 inhibitors led to a significantly greater change from baseline in the HbA1c levels (WMD -0.30 %; 95 % CI -0.47 to -0.13 %, p < 0.001) and fasting plasma glucose levels (WMD -0.50 mmol/L; 95 % CI -0.89 to -0.11 mmol/L, p = 0.01) compared with AGI treatment. Compared with AGIs, treatment with DPP-4 inhibitors was associated with a significantly greater increase in the weight change from baseline (WMD 0.89 kg; 95 % CI 0.53-1.25, p < 0.001). Treatment with DPP-4 inhibitors was associated with a significantly greater increase in the fasting insulin level from baseline (WMD 0.63 µU/mL; 95 % CI 0.35-0.90 µU/mL, p < 0.001). DPP-4 inhibitors significantly improved homeostatic model assessment for β-cell function in type 2 diabetes patients compared with AGI treatment (WMD 5.43; 95 % CI 1.01-9.85, p = 0.02). DPP-4 inhibitors were associated with a significantly greater decrease in the cholesterol (CHO) level (WMD -0.19 mmol/L; 95 % CI -0.19 to -0.19 mmol/L, p < 0.001) and a significantly greater decrease in the low-density lipoprotein cholesterol (LDL-C) level (WMD -0.16 mmol/L; 95 % CI -0.26 to -0.05 mmol/L, p = 0.003). Compared with AGIs (813 participants), treatment with DPP-4 inhibitors (1031 participants) was associated with a significantly lower incidence of drug-related adverse event (OR 0.48; 95 % CI 0.36-0.64, p < 0.0001). The efficacy of glucose control and improvement of β-cell function, as well as total CHO and LDL-C decreases, in DPP-4 inhibitor treatment were superior to those with AGI treatment, and there was a lower incidence of drug-related AE.

Dipeptidyl peptidase-4 activity might be a link between tumour necrosis factor alpha and insulin resistance in type 1 diabetes.

PubMed

Duvnjak, Lea; Blaslov, Kristina; Perković, Matea Nikolac; Ćuća, Jadranka Knežević

2016-08-01

Tumour necrosis factor alpha (TNF α) leads to β cell damage in type 1 diabetes (T1DM) but also causes insulin resistance (IR). It modulates dipeptidyl peptidase-4 (DPP-4) activity, adipokine linked with both IR and T1DM. We were interested if there is an association of TNF α in conjunction with DPP-4 and IR in T1DM. DPP-4 activity, TNF α concentration measurements, and insulin sensitivity calculation using estimated glucose disposal rate (eGDR) equation were performed in 70 T1DM patients. They were divided into two groups according to eGDR median. The group with higher IR had higher value of DPP-4 activity (27.57 ± 1.77 vs. 18.33 ± 1.14, p < 0.001) and TNF α concentration (12.91 ± 0.83 vs. 6.72 ± 0.36, p < 0.001). TNF α concentration and DPP-4 activity negatively correlated with eGDR (r = -0.616, p < 0.001 and r = -0.643, p < 0.001) while correlating positively with each other (r = 0.422; p = 0.001). The linear regression showed that eGDR decreases for 0.166 mg kg(-1) min(-1) by TNF α concentration increase of 1 pg/mL (p < 0.001) and for 0.090 mg kg(-1) min(-1) by DPP-4 activity increase of 1 U/L (p = 0.001) when adjusted for age, gender disease duration, glycated haemoglobin, body mass index and waist-to-hip ratio. eGDR decreased by additional 0.60 mg kg(-1) min(-1) (B = -0.150, p < 0.001) when DPP-4 activity was additionally adjusted for TNF α. TNF α concentration is associated with IR, correlates with its severity and increases the drop in insulin sensitivity modulated by DPP-4 activity. Whether TNF α involvement in the insulin signalling pathway is mediated by DPP-4 activity needs to be further evaluated.

The DPP-4 inhibitor vildagliptin impacts the gut microbiota and prevents disruption of intestinal homeostasis induced by a Western diet in mice.

PubMed

Olivares, Marta; Neyrinck, Audrey M; Pötgens, Sarah A; Beaumont, Martin; Salazar, Nuria; Cani, Patrice D; Bindels, Laure B; Delzenne, Nathalie M

2018-05-25

Dipeptidyl peptidase 4 (DPP-4) inhibitors are agents designed to increase the half-life of incretins. Although they are administered orally, little is known about their effects on the gut microbiota and functions, despite the fact that some bacteria present in the gut microbiota exhibit DPP-4-like activity. Our objective was to study the impact of the DPP-4 inhibitor vildagliptin on gut functions and the intestinal ecosystem in a murine model of obesity induced by a Western diet (WD). Twenty seven male C57BL/6J mice were randomised to receive a control diet, a WD (45% kJ from fat and 17% kJ from sucrose) or a WD + vildagliptin (0.6 mg/ml in drinking water) for 8 weeks. Vildagliptin significantly reduced DPP-4 activity in the caecal content and faeces. Vildagliptin impacted on the composition of the gut microbiota and its metabolic activity. It mainly decreased Oscillibacter spp. (a direct effect independent of DPP-4 activity was shown on cultured O. valericigenes), increased Lactobacillus spp. and propionate, and reduced the ligands of Toll-like receptors 2 and 4. Vildagliptin protected against the reductions in crypt depth and ileal expression of antimicrobial peptides induced by the WD. In the liver, the expression of immune cell populations (Cd3g and Cd11c [also known as Itgax]) and cytokines was decreased in the WD + vildagliptin-fed mice compared with the WD-fed group. Ex vivo exposure of precision-cut liver slices to vildagliptin showed that this response was not related to a direct effect of the drug on the liver tissue. Our study is the first to consider the DPP-4-like activity of the gut microbiota as a target of DPP-4 inhibition. We propose that vildagliptin exerts beneficial effects at the intestinal level in association with modulation of gut microbiota, with consequences for hepatic immunity. If relevant in humans, this could open new therapeutic uses of DPP-4 inhibition to tackle gut dysfunctions in different pathophysiological contexts. The sequences used for analysis can be found in the MG-RAST database under the project name MYNEWGUT3.

Anti-inflammatory effects on ischemia/reperfusion-injured lung transplants by the cluster of differentiation 26/dipeptidylpeptidase 4 (CD26/DPP4) inhibitor vildagliptin.

PubMed

Jang, Jae-Hwi; Yamada, Yoshito; Janker, Florian; De Meester, Ingrid; Baerts, Lesley; Vliegen, Gwendolyn; Inci, Ilhan; Chatterjee, Shampa; Weder, Walter; Jungraithmayr, Wolfgang

2017-03-01

We showed previously that stromal cell-derived factor 1 (SDF-1) is a substrate of cluster of differentiation 26/dipeptidylpeptidase 4 (CD26/DPP4) and exerts regenerative properties on acute lung ischemia-reperfusion injury on CD26/DPP4 inhibition. Here, we extend our studies to test whether an intermediate recovery of lung transplants from ischemia/reperfusion injury by CD26/DPP4 inhibition can be achieved for up to 14 days. Syngeneic mouse lung transplantation (Tx) was performed in C57BL/6 and in CD26-/- mice by applying 18 hours of cold ischemia. Donor lungs were preconditioned with saline or the CD26/DPP4 inhibitor vildagliptin (1 μg/mL [3 μM]). In vitro, the influence of vildagliptin and SDF-1 on the macrophage cell line RAW 264.7 was tested. Transplants were analyzed up to 14 days after Tx for the expression of SDF-1, tumor necrosis factor-α (TNF-α), interleukin-10, intercellular adhesion molecule-1 (ICAM-1), immune cell infiltration, and oxygenation. Cold ischemic time of 18 hours with vildagliptin preconditioning elevated lung SDF-1 levels (P = .0011) and increased interleukin-10-producing macrophages (P = .0165) compared with the control. SDF-1 reduced macrophage-derived TNF-α (P = .0248) in vitro. Five hours after Tx, vildagliptin significantly reduced macrophages and neutrophils (P = .0306), decreased ICAM-1 expression (P = .002), and improved transplant oxygenation (P = .0181). Seven days after Tx, grafts were preserved on CD26/DPP4-inhibition: perivascular macrophages (P = .0046) and TNF-α (P = .0013) were reduced as well as T and B cells. ICAM-1 was absent in CD26/DPP4-inhibited grafts at all time points. This study proves an intermediate improvement of ischemia/reperfusion-injured lung transplants by the CD26/DPP4-inhibitor vildagliptin up to 14 days. Enhanced levels of SDF-1 induced an anti-inflammatory effect on a cellular and protein level, and render CD26/DPP4 inhibition preconditioning effective for the protection from lung ischemia/reperfusion injury. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

A Novel Polyphenol Conjugate Sensitizes Cisplatin-Resistant Head and Neck Cancer Cells to Cisplatin via Nrf2 Inhibition.

PubMed

Kim, Eun Hye; Jang, Hyejin; Roh, Jong-Lyel

2016-11-01

Many cancer cells show acquired resistance to chemotherapeutic agents, such as cisplatin. This is a major cause of cancer treatment failure, and novel agents to overcome resistance are thus urgently required. A novel synthetic polyphenol conjugate, (E)-3-(3,5-dimethoxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one (DPP-23), selectively kills tumor cells via the reactive oxygen species (ROS)-mediated unfolded protein response. We investigated the ability of DPP-23 to overcome cisplatin resistance in head and neck cancer (HNC) cells and further clarified its molecular mechanisms of action. Cisplatin-resistant HNC cell lines and their parental and other HNC cell lines were used. The effects of cisplatin and DPP-23 were assessed alone and in combination in HNC and normal cells using cell viability, cell cycle, and cell death assays, by measuring glutathione (GSH), ROS, and protein levels, and via preclinical mouse studies. DPP-23 induced selective cell death in HNC cells, including cisplatin-resistant HNC cells, but spared normal cells, via cellular GSH depletion and ROS accumulation. The effect was blocked by the antioxidant N-acetyl-L-cysteine. DPP-23 activated p53 and its related cell death pathways via a robust accumulation of cellular ROS that involved inhibition of nuclear factor erythroid 2-related factor 2 antioxidant defense mechanisms. Thus, DPP-23 significantly overcame cisplatin resistance in HNC cells in vitro and in vivo As a promising anticancer strategy, ROS generation and subsequent selective cancer cell killing by DPP-23 might help to overcome cisplatin resistance in HNC. Mol Cancer Ther; 15(11); 2620-9. ©2016 AACR. ©2016 American Association for Cancer Research.

Tuning reactivity of diphenylpropynone derivatives with metal-associated amyloid-β species via structural modifications.

PubMed

Liu, Yuzhong; Kochi, Akiko; Pithadia, Amit S; Lee, Sanghyun; Nam, Younwoo; Beck, Michael W; He, Xiaoming; Lee, Dongkuk; Lim, Mi Hee

2013-07-15

A diphenylpropynone derivative, DPP2, has been recently demonstrated to target metal-associated amyloid-β (metal-Aβ) species implicated in Alzheimer's disease (AD). DPP2 was shown to interact with metal-Aβ species and subsequently control Aβ aggregation (reactivity) in vitro; however, its cytotoxicity has limited further biological applications. In order to improve reactivity toward Aβ species and lower cytotoxicity, along with gaining an understanding of a structure-reactivity-cytotoxicity relationship, we designed, prepared, and characterized a series of small molecules (C1/C2, P1/P2, and PA1/PA2) as structurally modified DPP2 analogues. A similar metal binding site to that of DPP2 was contained in these compounds while their structures were varied to afford different interactions and reactivities with metal ions, Aβ species, and metal-Aβ species. Distinct reactivities of our chemical family toward in vitro Aβ aggregation in the absence and presence of metal ions were observed. Among our chemical series, the compound (C2) with a relatively rigid backbone and a dimethylamino group was observed to noticeably regulate both metal-free and metal-mediated Aβ aggregation to different extents. Using our compounds, cell viability was significantly improved, compared to that with DPP2. Lastly, modifications on the DPP framework maintained the structural properties for potential blood-brain barrier (BBB) permeability. Overall, our studies demonstrated that structural variations adjacent to the metal binding site of DPP2 could govern different metal binding properties, interactions with Aβ and metal-Aβ species, reactivity toward metal-free and metal-induced Aβ aggregation, and cytotoxicity of the compounds, establishing a structure-reactivity-cytotoxicity relationship. This information could help gain insight into structural optimization for developing nontoxic chemical reagents toward targeting metal-Aβ species and modulating their reactivity in biological systems.

Berry and Citrus Phenolic Compounds Inhibit Dipeptidyl Peptidase IV: Implications in Diabetes Management

PubMed Central

Fan, Junfeng; Lila, Mary Ann; Yousef, Gad

2013-01-01

Beneficial health effects of fruits and vegetables in the diet have been attributed to their high flavonoid content. Dipeptidyl peptidase IV (DPP-IV) is a serine aminopeptidase that is a novel target for type 2 diabetes therapy due to its incretin hormone regulatory effects. In this study, well-characterized anthocyanins (ANC) isolated from berry wine blends and twenty-seven other phenolic compounds commonly present in citrus, berry, grape, and soybean, were individually investigated for their inhibitory effects on DPP-IV by using a luminescence assay and computational modeling. ANC from blueberry-blackberry wine blends strongly inhibited DPP-IV activity (IC50, 0.07 ± 0.02 to >300 μM). Of the twenty-seven phenolics tested, the most potent DPP-IV inhibitors were resveratrol (IC50, 0.6 ± 0.4 nM), luteolin (0.12 ± 0.01 μM), apigenin (0.14 ± 0.02 μM), and flavone (0.17 ± 0.01 μM), with IC50 values lower than diprotin A (4.21 ± 2.01 μM), a reference standard inhibitory compound. Analyses of computational modeling showed that resveratrol and flavone were competitive inhibitors which could dock directly into all three active sites of DPP-IV, while luteolin and apigenin docked in a noncompetitive manner. Hydrogen bonding was the main binding mode of all tested phenolic compounds with DPP-IV. These results indicate that flavonoids, particularly luteolin, apigenin, and flavone, and the stilbenoid resveratrol can act as naturally occurring DPP-IV inhibitors. PMID:24069048

Simulation assessment of the direct‐push permeameter for characterizing vertical variations in hydraulic conductivity

USGS Publications Warehouse

Liu, Gaisheng; Bohling, Geoffrey C.; Butler, James J.

2008-01-01

The direct‐push permeameter (DPP) is a tool for the in situ characterization of hydraulic conductivity (K) in shallow, unconsolidated formations. This device, which consists of a short screened section with a pair of pressure transducers near the screen, is advanced into the subsurface with direct‐push technology. K is determined through a series of injection tests conducted between advancements. Recent field work by Butler et al. (2007) has shown that the DPP holds great potential for describing vertical variations in K at an unprecedented level of detail, accuracy and speed. In this paper, the fundamental efficacy of the DPP is evaluated through a series of numerical simulations. These simulations demonstrate that the DPP can provide accurate K information under conditions commonly faced in the field. A single DPP test provides an effective K for the domain immediately surrounding the interval between the injection screen and the most distant pressure transducer. Features that are thinner than that interval can be quantified by reducing the vertical distance between successive tests and analyzing the data from all tests simultaneously. A particular advantage of the DPP is that, unlike most other single borehole techniques, a low‐K skin or a clogged screen has a minimal impact on the K estimate. In addition, the requirement that only steady‐shape conditions be attained allows for a dramatic reduction in the time required for each injection test.

Prolyl oligopeptidase and dipeptidyl peptidase II/dipeptidyl peptidase IV ratio in the cerebrospinal fluid in Parkinson's disease: historical overview and future prospects.

PubMed

Nagatsu, Toshiharu

2017-06-01

Prolyl oligopeptidase (also named prolyl endopeptidase; PREP) hydrolyzes the Pro-Xaa bonds of biologically active oligopeptides on their carboxyl side. In 1987, we detected PREP activity in human cerebrospinal fluid (CSF) using highly sensitive liquid chromatography-fluorometry with succinyl-Gly-Pro-4-methyl-coumarin amide as a new synthetic substrate, and found a marked decrease in its activity in the cerebrospinal fluid (CSF) from patients with Parkinson's disease (PD) as compared with its level in control patients without neurological diseases. In 2013, Hannula et al. found co-localization of PREP with α-synuclein in the postmortem PD brain. Several recent studies also suggest that the level of PREP in the brain of PD patients may be related to dopamine (DA) cell death via promotion of α-synuclein oligomerization and that inhibitors of PREP may play a neuroprotective role in PD. Although the relationship between another family of prolyl oligopeptidase enzymes, dipeptidyl peptidase II (DPP II) and dipeptidyl peptidase IV (DPP IV), and α-synuclein in the PD brain is not yet clear, we found that the DPP II activity/DPP IV activity ratio in the CSF was significantly increased in PD patients. This review discusses the possibility of PREP as well as the DPP II/DPP IV ratio in the CSF as potential biomarkers of PD.

Identification of dipeptidyl peptidase-IV inhibitory peptides from mare whey protein hydrolysates.

PubMed

Song, J J; Wang, Q; Du, M; Ji, X M; Mao, X Y

2017-09-01

Inhibition of dipeptidyl peptidase-IV (DPP-IV) activity is a promising strategy for treatment of type 2 diabetes. In the current study, DPP-IV inhibitory peptides were identified from mare whey protein hydrolysates obtained by papain. The results showed that all the mare whey protein hydrolysates obtained at various hydrolysis durations possessed more potent DPP-IV inhibitory activity compared with intact whey protein. The 4-h hydrolysates showed the greatest DPP-IV inhibitory activity with half-maximal inhibitory concentration of 0.18 mg/mL. The 2 novel peptides from 4-h hydrolysate fractions separated by successive chromatographic steps were characterized by liquid chromatography-electrospray ionization tandem mass spectrometry. The novel peptides Asn-Leu-Glu-Ile-Ile-Leu-Arg and Thr-Gln-Met-Val-Asp-Glu-Glu-Ile-Met-Glu-Lys-Phe-Arg, which corresponded to β-lactoglobulin 1 f(71-77) and β-lactoglobulin 1 f(143-155), demonstrated DPP-IV inhibitory activity with half-maximal inhibitory concentrations of 86.34 and 69.84 μM, respectively. The DPP-IV inhibitory activity of the 2 peptides was retained or even improved after simulated gastrointestinal digestion in vitro. Our findings indicate that mare whey protein-derived peptides may possess potential as functional food ingredients in the management of type 2 diabetes. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Inhibition of CD26/DPP IV attenuates ischemia/reperfusion injury in orthotopic mouse lung transplants: the pivotal role of vasoactive intestinal peptide.

PubMed

Jungraithmayr, Wolfgang; De Meester, Ingrid; Matheeussen, Veerle; Inci, Ilhan; Augustyns, Koen; Scharpé, Simon; Weder, Walter; Korom, Stephan

2010-04-01

The T cell activation Ag CD26/dipeptidylpeptidase IV (DPP IV) combines co-stimulatory and enzymatic properties. Catalytically, it functions as an exopeptidase, modulating biological activity of key chemokines and peptides. Here we investigated the effect of organ-specific inhibition of DPP IV catalytic activity on ischemia/reperfusion injury after extended ischemia in the mouse model of orthotopic single lung transplantation. C57BL/6 mice were syngeneically, transplanted, grafts were perfused and stored in Perfadex with (treated) or without (control) a DPP IV enzymatic activity inhibitor (AB192). Transplantation was performed after 18h cold ischemia time; following 2-h reperfusion, grafts were analyzed for oxygenation, thiobarbituric acid-reactive substances, histomorphology, and immunohistochemistry was performed for leukocyte Ag 6, myeloperoxidase, hemoxygenase 1, vasoactive intestinal protein (VIP), and real-time PCR for VIP. Treatment with the DPP IV inhibitor AB192 resulted in significant improvement of gas exchange, less lipid oxidation, preservation of parenchymal ultrastructure, reduced neutrophil infiltration, reduced myeloperoxidase expression, increased hemoxygenase 1 expression, pronounced expression of VIP in alveolar macrophages and increased mRNA expression of VIP. Inhibition of intragraft DPP IV catalytic activity with AB192 strikingly ameliorates ischemia/reperfusion injury after extended ischemia. Furthermore, preservation of endogenous intragraft VIP levels correlate with maintaining lung function and structural integrity. Copyright (c) 2009 Elsevier Inc. All rights reserved.

DPP-4 inhibitors improve liver dysfunction in type 2 diabetes mellitus.

PubMed

Kanazawa, Ippei; Tanaka, Ken-ichiro; Sugimoto, Toshitsugu

2014-09-17

Dipeptidyl peptidase-4 (DPP-4) inhibitors might have pleiotropic effects because receptors for incretin exist in various tissues, including liver. We examined whether DPP-4 inhibitors affect liver function in patients with type 2 diabetes. A retrospective review of 459 patients with type 2 diabetes who were prescribed DPP-4 inhibitors was performed. After exclusion of patients with hepatitis B or C, steroid use, and other diseases that might affect liver function and diabetes status, 224 patients were included in the analysis. Forty-four patients (19.6%) with liver injury defined by aspartate transaminase (AST) or alanine transaminase (ALT) over the normal level of 40 U/L. In the patients with liver injury, AST and ALT were significantly decreased after 6 months from the first date of DPP-4 prescription, with mean changes of -6.2 U/L [95% confidence interval (CI) -10.9 to -1.4, p=0.012] and of -11.9 U/L (95%CI -19.5 to -4.2, p=0.003), respectively. Percent changes in AST were significantly and negatively correlated with baseline AST and ALT (r=-0.27, p<0.001 and r=-0.23, p=0.002, respectively), and percent changes in ALT were also negatively correlated with them (r=-0.23, p=0.001 and r=-0.27, p<0.001, respectively). DPP-4 inhibitors improved liver dysfunction in patients with type 2 diabetes.

Serological and molecular diagnostic tests for canine visceral leishmaniasis in Brazilian endemic area: one out of five seronegative dogs are infected.

PubMed

Lopes, E G; Sevá, A P; Ferreira, F; Nunes, C M; Keid, L B; Hiramoto, R M; Ferreira, H L; Oliveira, T M F S; Bigotto, M F D; Galvis-Ovallos, F; Galati, E A B; Soares, R M

2017-09-01

Euthanasia of infected dogs is one of the measures adopted in Brazil to control visceral leishmaniasis (VL) in endemic areas. To detect infected dogs, animals are screened with the rapid test DPP® Visceral Canine Leishmaniasis for detection of antibodies against K26/K39 fusion antigens of amastigotes (DPP). DPP-positives are confirmed with an immunoenzymatic assay probing soluble antigens of promastigotes (ELISA), while DPP-negatives are considered free of infection. Here, 975 dogs from an endemic region were surveyed by using DPP, ELISA and real-time PCR (qPCR) for the diagnosis of VL. When DPP-negative dogs were tested by qPCR applied in blood and lymph node aspirates, 174/887 (19·6%) were positive in at least one sample. In a second sampling using 115 cases, the DPP-negative dogs were tested by qPCR in blood, lymph node and conjunctival swab samples, and 36/79 (45·6%) were positive in at least one sample. Low-to-moderate pairwise agreement was observed between all possible pair of tests. In conclusion, the official diagnosis of VL in dogs in Brazilian endemic areas failed to accuse an expressive number of infected animals and the impact of the low accuracy of serological tests in the success of euthanasia-based measure for VL control need to be assessed.

Molecular simulations reveal that the long range fluctuations of human DPP III change upon ligand binding.

PubMed

Tomić, A; Berynskyy, M; Wade, R C; Tomić, S

2015-11-01

The experimentally determined structures of human dipeptidyl peptidase III (DPP III) for the wild-type protein and for the complex of its E451A mutant with the peptide substrate, tynorphin, differ significantly in their overall shape. The two domains of the enzyme are separated by a wide cleft in the structure of the ligand-free enzyme, while in the ligand-bound mutant they are very close to each other, and the protein structure is extremely compact. Here, we applied a range of molecular dynamics simulation techniques to investigate the DPP III conformational landscape and the influence of ligand binding on the protein structure and dynamics. We used conventional, accelerated and steered methods to simulate DPP III and its complexes with tynorphin and with the preferred, synthetic, substrate Arg-Arg-2-naphthylamide. We found that DPP III can adopt a number of different forms in solution. The compact forms are more stable, but the open and partially closed states, spanning a wide range of conformations, can more effectively recognize the substrate which preferentially binds to the five-stranded β-core of the lower DPP III domain. The simulations indicated the existence of a dynamic equilibrium between open and semi-closed states and revealed two ways that the protein can close, leading to two distinct compact structures. The way in which the protein closes depends on the presence of the ligand.

Discovery of Potent and Selective Dipeptidyl Peptidase IV Inhibitors Derived from [beta]-Aminoamides Bearing Subsituted Triazolopiperazines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Dooseop; Kowalchick, Jennifer E.; Brockunier, Linda L.

2008-06-30

A series of {beta}-aminoamides bearing triazolopiperazines have been discovered as potent, selective, and orally active dipeptidyl peptidase IV (DPP-4) inhibitors by extensive structure-activity relationship (SAR) studies around the triazolopiperazine moiety. Among these, compound 34b with excellent in vitro potency (IC{sub 50} = 4.3 nM) against DPP-4, high selectivity over other enzymes, and good pharmacokinetic profiles exhibited pronounced in vivo efficacy in an oral glucose tolerance test (OGTT) in lean mice. On the basis of these properties, compound 34b has been profiled in detail. Further refinement of the triazolopiperazines resulted in the discovery of a series of extremely potent compounds withmore » subnanomolar activity against DPP-4 (42b-49b), that is, 4-fluorobenzyl-substituted compound 46b, which is notable for its superior potency (IC{sub 50} = 0.18 nM). X-ray crystal structure determination of compounds 34b and 46b in complex with DPP-4 enzyme revealed that (R)-stereochemistry at the 8-position of triazolopiperazines is strongly preferred over (S) with respect to DPP-4 inhibition.« less

Design and synthesis of aminocoumarin derivatives as DPP-IV inhibitors and anticancer agents.

PubMed

Soni, Rina; Soman, Shubhangi S

2018-09-01

DPP-IV "a moonlighting protein" has immerged as promising pathway to control Type 2 diabetes as well as found to play key role in earlier stages of cancer. Here we have reported design, synthesis and applications of aminocoumarin derivatives as DPP-IV inhibitors. Compounds have been synthesized and studied for their DPP-IV inhibition activity. Three compounds have shown moderate inhibition at 100 µM concentration. All compounds were also screened for their anticancer activity against A549 (Lung cancer cell line), MCF-7 (Breast cancer cell line) using MTT assay. One of the compounds has shown very good anticancer activity with IC 50 value 24 ± 0.1 nM against A549 cell line. Copyright © 2018 Elsevier Inc. All rights reserved.

Web-based tailored lifestyle programs: exploration of the target group's interests and implications for practice.

PubMed

Verheijden, Marieke W; Jans, Marielle P; Hildebrandt, Vincent H

2008-01-01

An important challenge in Web-based health promotion is to increase the reach of the target audience by taking the target groups' desires into consideration. Data from 505 members of a Dutch Internet panel (representative for Dutch Internet users) were used to asses the target group's interests and needs. 28% participated in Web-based tailored lifestyle programs, 57% expressed an interest in such programs, and 15% expressed no interest. Interest in Web-based programs was predominantly caused by a general interest in lifestyle and online tests. Participation in Web-based tailored lifestyle programs should not take more than 17 minutes per occasion. 84% were interested in follow-up testing after the initial participation. Responders were particularly interested in physical activity and nutrition. Hardly anyone was willing to pay for participation. The results from this study support the use of Web-based tailored lifestyle programs in behavior change efforts.

Economic Evaluation of Combined Diet and Physical Activity Promotion Programs to Prevent Type 2 Diabetes Among Persons at Increased Risk: A Systematic Review for the Community Preventive Services Task Force

PubMed Central

Li, Rui; Qu, Shuli; Zhang, Ping; Chattopadhyay, Sajal; Gregg, Edward W.; Albright, Ann; Hopkins, David; Pronk, Nicolaas P.

2016-01-01

Background Diabetes is a highly prevalent and costly disease. Studies indicate that combined diet and physical activity promotion programs can prevent type 2 diabetes among persons at increased risk. Purpose To systematically evaluate the evidence on cost, cost-effectiveness, and cost-benefit estimates of diet and physical activity promotion programs. Data Sources Cochrane Library, EMBASE, MEDLINE, PsycINFO, Sociological Abstracts, Web of Science, EconLit, and CINAHL through 7 April 2015. Study Selection English-language studies from high-income countries that provided data on cost, cost-effectiveness, or cost-benefit ratios of diet and physical activity promotion programs with at least 2 sessions over at least 3 months delivered to persons at increased risk for type 2 diabetes. Data Extraction Dual abstraction and assessment of relevant study details. Data Synthesis Twenty-eight studies were included. Costs were expressed in 2013 U.S. dollars. The median program cost per participant was $653. Costs were lower for group-based programs (median, $417) and programs implemented in community or primary care settings (median, $424) than for the U.S. DPP (Diabetes Prevention Program) trial and the DPP Outcomes Study ($5881). Twenty-two studies assessed the incremental cost-effectiveness ratios (ICERs) of the programs. From a health system perspective, 16 studies reported a median ICER of $13 761 per quality-adjusted life-year (QALY) saved. Group-based programs were more cost-effective (median, $1819 per QALY) than those that used individual sessions (median, $15 846 per QALY). No cost-benefit studies were identified. Limitation Information on recruitment costs and cost-effectiveness of translational programs implemented in community and primary care settings was limited. Conclusion Diet and physical activity promotion programs to prevent type 2 diabetes are cost-effective among persons at increased risk. Costs are lower when programs are delivered to groups in community or primary care settings. Primary Funding Source None. PMID:26167962

Text Message Support for Weight Loss in Patients With Prediabetes: A Randomized Clinical Trial.

PubMed

Fischer, Henry H; Fischer, Ilana P; Pereira, Rocio I; Furniss, Anna L; Rozwadowski, Jeanne M; Moore, Susan L; Durfee, Michael J; Raghunath, Silvia G; Tsai, Adam G; Havranek, Edward P

2016-08-01

Although the benefits of in-person Diabetes Prevention Program (DPP) classes for diabetes prevention have been demonstrated in trials, effectiveness in clinical practice is limited by low participation rates. This study explores whether text message support enhances weight loss in patients offered DPP classes. English- and Spanish-speaking patients with prediabetes (n = 163) were randomized to the control group, which only received an invitation to DPP classes as defined by the Centers for Disease Control and Prevention, or to the text message-augmented intervention group, which also received text messages adapted from the DPP curriculum for 12 months. Mean weight decreased 0.6 pounds (95% CI -2.7 to 1.6) in the control group and 2.6 pounds (95% CI -5.5 to 0.2) in the intervention group (P value 0.05). Three percent weight loss was achieved by 21.5% of participants in the control group (95% CI 12.5-30.6), compared with 38.5% in the intervention group (95% CI 27.7-49.3) (absolute difference 17.0%; P value 0.02). Mean glycated hemoglobin (HbA1c) increased by 0.19% or 2.1 mmol/mol (95% CI -0.1 to 0.5%) and decreased by 0.09% or 1.0 mmol/mol (95% CI -0.2 to 0.0%) in the control group and intervention participants, respectively (absolute difference 0.28%; P value 0.07). Stratification by language demonstrated a significant treatment effect in Spanish speakers but not in English speakers. Text message support can lead to clinically significant weight loss in patients with prediabetes. Further study assessing effect by primary language and in an operational setting is warranted. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Lower dipeptidyl peptidase-4 following exercise training plus weight loss is related to increased insulin sensitivity in adults with metabolic syndrome.

PubMed

Malin, Steven K; Huang, Hazel; Mulya, Anny; Kashyap, Sangeeta R; Kirwan, John P

2013-09-01

Dipeptidyl peptidase-4 (DPP-4) is a circulating glycoprotein that impairs insulin-stimulated glucose uptake and is linked to obesity and metabolic syndrome. However, the effect of exercise on plasma DPP-4 in adults with metabolic syndrome is unknown. Therefore, we determined the effect of exercise on DPP-4 and its role in explaining exercise-induced improvements in insulin sensitivity. Fourteen obese adults (67.9±1.2 years, BMI: 34.2±1.1kg/m(2)) with metabolic syndrome (ATP III criteria) underwent a 12-week supervised exercise intervention (60min/day for 5 days/week at ∼85% HRmax). Plasma DPP-4 was analyzed using an enzyme-linked immunosorbent assay. Insulin sensitivity was measured using the euglycemic-hyperinsulinemic clamp (40mU/m(2)/min) and estimated by HOMA-IR. Visceral fat (computerized tomography), 2-h glucose levels (75g oral glucose tolerance), and basal fat oxidation as well as aerobic fitness (indirect calorimetry) were also determined before and after exercise. The intervention reduced visceral fat, lowered blood pressure, glucose and lipids, and increased aerobic fitness (P<0.05). Exercise improved clamp-derived insulin sensitivity by 75% (P<0.001) and decreased HOMA-IR by 15% (P<0.05). Training decreased plasma DPP-4 by 10% (421.8±30.1 vs. 378.3±32.5ng/ml; P<0.04), and the decrease in DPP-4 was associated with clamp-derived insulin sensitivity (r=-0.59; P<0.04), HOMA-IR (r=0.59; P<0.04) and fat oxidation (r=-0.54; P<0.05). Increased fat oxidation also correlated with lower 2-h glucose levels (r=-0.64; P<0.02). Exercise training reduces plasma DPP-4, which may be linked to elevated insulin sensitivity and fat oxidation. Maintaining low plasma DPP-4 concentrations is a potential mechanism whereby exercise plus weight loss prevents/delays the onset of type 2 diabetes in adults with metabolic syndrome. Copyright © 2013 Elsevier Inc. All rights reserved.

Dipeptidyl peptidase 4 inhibitor attenuates obesity-induced myocardial fibrosis by inhibiting transforming growth factor-βl and Smad2/3 pathways in high-fat diet-induced obesity rat model.

PubMed

Hong, Seul-Ki; Choo, Eun-Ho; Ihm, Sang-Hyun; Chang, Kiyuk; Seung, Ki-Bae

2017-11-01

Obesity-induced myocardial fibrosis may lead to diastolic dysfunction and ultimately heart failure. Activation of the transforming growth factor (TGF)-βl and its downstream Smad2/3 pathways may play a pivotal role in the pathogenesis of obesity-induced myocardial fibrosis, and the antidiabetic dipeptidyl peptidase 4 inhibitors (DPP4i) might affect these pathways. We investigated whether DPP4i reduces myocardial fibrosis by inhibiting the TGF-β1 and Smad2/3 pathways in the myocardium of a diet-induced obesity (DIO) rat model. Eight-week-old male spontaneously hypertensive rats (SHRs) were fed either a normal fat diet (chow) or a high-fat diet (HFD) and then the HFD-fed SHRs were randomized to either the DPP4i (MK-0626) or control (distilled water) groups for 12weeks. At 20weeks old, all the rats underwent hemodynamic and metabolic studies and Doppler echocardiography. Compared with the normal fat diet (chow)-fed SHRs, the HFD-fed SHRs developed a more intense degree of hyperglycemia and dyslipidemia and showed a constellation of left ventricular (LV) diastolic dysfunction, and exacerbated myocardial fibrosis, as well as activation of the TGF-β1 and Smad2/3 pathways. DPP4i significantly improved the metabolic and hemodynamic parameters. The echocardiogram showed that DPP4i improved the LV diastolic dysfunction (early to late ventricular filling velocity [E/A] ratio, 1.49±0.21 vs. 1.77±0.09, p<0.05). Furthermore, DPP4i significantly reduced myocardial fibrosis and collagen production by the myocardium and suppressed TGF-β1 and phosphorylation of Smad2/3 in the heart. In addition, DPP4i decreased TGF-β1-induced collagen production and TGF-β1-mediated phosphorylation and nuclear translocation of Smad2/3 in rat cardiac fibroblasts. In conclusion, DPP4 inhibition attenuated myocardial fibrosis and improved LV diastolic dysfunction in a DIO rat model by modulating the TGF-β1 and Smad2/3 pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

Role of the Diphosphine Chelate in Emissive, Charge-Neutral Iridium(III) Complexes.

PubMed

Liao, Jia-Ling; Devereux, Leon R; Fox, Mark A; Yang, Chun-Chieh; Chiang, Yu-Cheng; Chang, Chih-Hao; Lee, Gene-Hsiang; Chi, Yun

2018-01-12

A class of neutral tris-bidentate Ir III metal complexes incorporating a diphosphine as a chelate is prepared and characterized here for the first time. Treatment of [Ir(dppBz)(tht)Cl 3 ] (1, dppBz=1,2-bis(diphenylphosphino)benzene, tht=tetrahydrothiophene) with fppzH (3-trifluoromethyl-5-(2'-pyridyl)-1H-pyrazole) afforded the dichloride complexes, trans-(Cl,Cl)[Ir(dppBz)(fppz)Cl 2 ] (2) and cis-(Cl,Cl)[Ir(dppBz)(fppz)Cl 2 ] (3). The reaction of 3 with the dianionic chelate precursor, 5,5'-di(trifluoromethyl)-3,3'-bipyrazole (bipzH 2 ) or 5,5'-(1-methylethylidene)-bis(3-trifluoromethyl-1H-pyrazole) (mepzH 2 ), in DMF gave the tris-bidentate complex [Ir(dppBz)(fppz)(bipz)] (4) or [Ir(dppBz)(fppz)(mepz)] (5), respectively. In contrast, a hydride complex [Ir(dppBz)(fppz)(bipzH)H] (6) was isolated instead of 4 in protic solvent, namely: diethylene glycol monomethyl ether (DGME). All complexes 2-6 are luminescent in powder form and thin films where the dichlorides (2, 3) emit with maxima at 590-627 nm (orange) and quantum yields (QYs) up to 90 % whereas the tris-bidentate (4, 5) and hydride (6) complexes emit at 455-458 nm (blue) with QYs up to 70 %. Hybrid (time-dependent) DFT calculations showed considerable metal-to-ligand charge transfer contribution to the orange-emitting 2 and 3 but substantial ligand-centered 3 π-π* transition character in the blue-emitting 4-6. The dppBz does not participate in the radiative transitions in 4-6, but it provides the rigidity and steric bulk needed to promote the luminescence by suppressing the self-quenching in the solid state. Fabrication of an organic light-emitting diode (OLED) with dopant 5 gave a deep-blue CIE chromaticity of (0.16, 0.15). Superior blue emitters, which are vital in OLED applications, may be found in other neutral Ir III complexes containing phosphine chelates. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Recruiting low-income postpartum women into two weight loss interventions: in-person versus Facebook delivery.

PubMed

Silfee, Valerie J; Lopez-Cepero, Andrea; Lemon, Stephenie C; Estabrook, Barbara; Nguyen, Oanh; Rosal, Milagros C

2018-02-21

Several studies, such as the Diabetes Prevention Program (DPP), have provided foundational evidence for the efficacy of lifestyle interventions on weight loss and cardiometabolic prevention. However, translating these interventions to real-world settings and engaging at-risk populations has proven difficult. Social media-delivered interventions have high potential for reaching high-risk populations, but there remains a need to understand the extent to which these groups are interested in social media as a delivery mode. One potential way to this is by examining recruitment rates as a proxy for interest in the intervention delivery format. The aim of this study was to describe the recruitment rates of overweight and obese low-income postpartum women into two asynchronous behavioral weight loss interventions: one delivered in-person and the other delivered via Facebook. Both interventions used the same recruitment methods: participants were overweight low-income postpartum women who were clients of Women, Infants, and Children (WIC) clinics in Worcester, MA, screened for the study by nutritionists during routine WIC visits. Similarly, eligibility criteria were the same for both interventions except for a requirement for the Facebook-delivered intervention to currently use Facebook at least once per week. Among women pre-eligible for the in-person intervention, 42.6% gave permission to be contacted to determine full eligibility and 24.1% of eligible women enrolled. Among women pre-eligible for the Facebook intervention, 31.8% gave permission to be contacted and 28.5% of eligible women enrolled. Recruitment rates for a Facebook-based weight loss intervention were similar to recruitment rates for an in-person intervention, suggesting similar interest in the two program delivery modes among low-income postpartum women.

Structural studies of a bifunctional inhibitor of neprilysin and DPP-IV.

PubMed

Oefner, Christian; Pierau, Sabine; Schulz, Henk; Dale, Glenn E

2007-09-01

Neutral endopeptidase (NEP) is the major enzyme involved in the metabolic inactivation of a number of bioactive peptides including the enkephalins, substance P, endothelin, bradykinin and atrial natriuretic factor, as well as the incretin hormone glucagon-like peptide 1 (GLP-1), which is a potent stimulator of insulin secretion. The activity of GLP-1 is also rapidly abolished by the serine protease dipeptidyl peptidase IV (DPP-IV), which led to an elevated interest in inhibitors of this enzyme for the treatment of type II diabetes. A dual NEP/DPP-IV inhibitor concept is proposed, offering an alternative strategy for the treatment of type 2 diabetes. Here, the synthesis and crystal structures of the soluble extracellular domain of human NEP (residues 52-749) complexed with the NEP, competitive and potent dual NEP/DPP-IV inhibitor MCB3937 are described.

Ubx dynamically regulates Dpp signaling by repressing Dad expression during copper cell regeneration in the adult Drosophila midgut

PubMed Central

Li, Hongjie; Qi, Yanyan; Jasper, Heinrich

2016-01-01

The gastrointestinal (GI) tract of metazoans is lined by a series of regionally distinct epithelia. To maintain structure and function of the GI tract, regionally diversified differentiation of somatic stem cell (SC) lineages is critical. The adult Drosophila midgut provides an accessible model to study SC regulation and specification in a regionally defined manner. SCs of the posterior midgut (PM) have been studied extensively, but the control of SCs in the middle midgut (MM) is less well understood. The MM contains a stomach-like copper cell region (CCR) that is regenerated by gastric stem cells (GSSCs) and contains acid-secreting copper cells (CCs). Bmp-like Decapentaplegic (Dpp) signaling determines the identity of GSSCs, and is required for CC regeneration, yet the precise control of Dpp signaling activity in this lineage remains to be fully established. Here, we show that Dad, a negative feedback regulator of Dpp signaling, is dynamically regulated in the GSSC lineage to allow CC differentiation. Dad is highly expressed in GSSCs and their first daughter cells, the gastroblasts (GBs), but has to be repressed in differentiating CCs to allow Dpp-mediated differentiation into CCs. We find that the Hox gene ultrabithorax (Ubx) is required for this regulation. Loss of Ubx prevents Dad repression in the CCR, resulting in defective CC regeneration. Our study highlights the need for dynamic control of Dpp signaling activity in the differentiation of the GSSC lineage and identifies Ubx as a critical regulator of this process. PMID:27570230

MicroRNA-451 sensitizes lung cancer cells to cisplatin through regulation of Mcl-1.

PubMed

Cheng, Dezhi; Xu, Yi; Sun, Changzheng; He, Zhifeng

2016-12-01

As one of the most widely used chemotherapy drugs for lung cancer, chemoresistance of cisplatin (DPP) is one of the major hindrances in treatment of this malignancy. The microRNAs (miRNAs) have been identified to mediate chemotherapy drug resistance. MiR-451 as a tumor suppressor has been evaluated its potential effect on the sensitivity of cancer cells to DDP. However, the role of miR-451 in regulatory mechanism of chemosensitivity in lung cancer cells is still largely unknown. In this study, we first constructed a cisplatin-resistant A549 cell line (A549/DPP) accompanied with a decreased expression of miR-451 and an increased expression of Mcl-1in the drug resistant cells compared with the parental cells. Exogenous expression of miR-451 level in A549/DPP was found to sensitize their reaction to the treatment of cisplatin, which coincides with reduced expression of Mcl-1. Interestingly, Mcl-1 knockdown in A549/DPP cells increased the chemosensitivity to DPP, suggesting the dependence of Mcl-1 regulation in miR-451 activity. Moreover, miR-451 can restore cisplatin treatment response in cisplatin-resistant xenografts in vivo, while Mcl-1 protein levels were decreased. Thus, these findings provided that in lung cancer cells, tumor suppressor miR-451 enhanced DPP sensitivity via regulation of Mcl-1 expression, which could be served as a novel therapeutic target for the treatment of chemotherapy resistant in lung cancer.

A comparison of effects of DPP-4 inhibitor and SGLT2 inhibitor on lipid profile in patients with type 2 diabetes.

PubMed

Cha, Seon-Ah; Park, Yong-Moon; Yun, Jae-Seung; Lim, Tae-Seok; Song, Ki-Ho; Yoo, Ki-Dong; Ahn, Yu-Bae; Ko, Seung-Hyun

2017-04-13

Previous studies suggest that dipeptidyl peptidase-4 (DPP-4) inhibitors and sodium glucose cotransporter 2 (SGLT2) inhibitors have different effects on the lipid profile in patients with type 2 diabetes. We investigated the effects of DPP-4 inhibitors and SGLT2 inhibitors on the lipid profile in patients with type 2 diabetes. From January 2013 to December 2015, a total of 228 patients with type 2 diabetes who were receiving a DPP-4 inhibitor or SGLT2 inhibitor as add-on therapy to metformin and/or a sulfonylurea were consecutively enrolled. We compared the effects of DPP-4 inhibitors and SGLT2 inhibitors on the lipid profile at baseline and after 24 weeks of treatment. To compare lipid parameters between the two groups, we used the analysis of covariance (ANCOVA). A total of 184 patients completed follow-up (mean age: 53.1 ± 6.9 years, mean duration of diabetes: 7.1 ± 5.7 years). From baseline to 24 weeks, HDL-cholesterol (HDL-C) levels were increased by 0.5 (95% CI, -0.9 to 2.0) mg/dl with a DPP-4 inhibitor and by 5.1 (95% CI, 3.0 to 7.1) mg/dl with an SGLT2 inhibitor (p = 0.001). LDL-cholesterol (LDL-C) levels were reduced by 8.4 (95% CI, -14.0 to -2.8) mg/dl with a DPP-4 inhibitor, but increased by 1.3 (95% CI, -5.1 to 7.6) mg/dl with an SGLT2 inhibitor (p = 0.046). There was no significant difference in the mean hemoglobin A1c (8.3 ± 1.1 vs. 8.0 ± 0.9%, p = 0.110) and in the change of total cholesterol (TC) (p = 0.836), triglyceride (TG) (p = 0.867), apolipoprotein A (p = 0.726), apolipoprotein B (p = 0.660), and lipoprotein (a) (p = 0.991) between the DPP-4 inhibitor and the SGLT2 inhibitor. The SGLT2 inhibitor was associated with a significant increase in HDL-C and LDL-C after 24 weeks of SGLT2 inhibitor treatment in patients with type 2 diabetes compared with those with DPP-4 inhibitor treatment in this study. This study was conducted by retrospective medical record review.

Postpartum suppression of ovarian activity with a Deslorelin implant enhanced uterine involution in lactating dairy cows.

PubMed

Silvestre, F T; Bartolome, J A; Kamimura, S; Arteche, A C; Pancarci, S M; Trigg, T; Thatcher, W W

2009-01-01

Holstein cows received, subcutaneously a non-degradable implant containing 5mg of the GnRH agonist Deslorelin (DESL) or no implant (CON) at 2+/-1 days postpartum (dpp). All cows were injected with PGF(2alpha) at 9 dpp. Previous pregnant (PPH) and non-pregnant uterine horns (PNPH) were determined by palpation per rectum. In Experiment 1, cows [DESL implant (n=10) and CON (n=9)] were examined by ultrasonography to record ovarian structures (23, 30 and 37 dpp) and uterine horn and cervical diameters (16, 23, 30 and 37 dpp). Uterine tone was scored before ultrasonography. Vaginoscopy was conducted just after ultrasonography examination to assess cervical discharge and color of the external cervical os. Blood samples were collected on a weekly basis for hormonal analyses. In Experiment 2, cows [DESL implant (n=77) and CON (n=70)] were palpated per rectum and vaginoscopy at 30 dpp for scoring of uterine tone, uterine horns, cervical diameter, and discharge. Blood samples were collected only at 9 dpp. In Experiment 1, DESL-implant-treated cows had more Class 1 follicles (P<0.01), less Class 2 (P<0.01) and Class 3 follicles (P<0.01) and no corpus luteum (CL) formation (P<0.01). In CON cows, six of nine animals had visible CL at 25+/-7 dpp. At 9 dpp plasma concentration of E(2), P(4) (P<0.01) and PGFM (P<0.05) were less in the DESL-implant treatment group. Diameter of PPH (P<0.01), PNPH (P<0.01) and cervix (P=0.08) were less in the DESL-implant treatment associated with greater uterine tone (P=0.07). The DESL-implant cows had a greater frequency of clear cervical discharge (P=0.09) and pink cervical os (P=0.06). In Experiment 2, plasma concentrations of PGFM were less at 9 dpp in DESL-implant treatment (P<0.01). Diameters of the PPH (P<0.01) and PNPH (P<0.01) were less and more uterine tone (P<0.01) in the DESL-implant treatment. Diameter of cervix and frequency of a cervical discharge score did not differ between treatments. Treatment with non-degradable Deslorelin (5mg) implant during postpartum: (1) suppressed ovarian follicular development, (2) enhanced physical involution of the uterus and cervix, (3) increased tone of the uterine wall, (4) decreased frequency of purulent cervical discharges, and (5) reduced inflammatory processes of the reproductive tract.

Diketopyrrolopyrrole Polymers for Organic Solar Cells.

PubMed

Li, Weiwei; Hendriks, Koen H; Wienk, Martijn M; Janssen, René A J

2016-01-19

Conjugated polymers have been extensively studied for application in organic solar cells. In designing new polymers, particular attention has been given to tuning the absorption spectrum, molecular energy levels, crystallinity, and charge carrier mobility to enhance performance. As a result, the power conversion efficiencies (PCEs) of solar cells based on conjugated polymers as electron donor and fullerene derivatives as electron acceptor have exceeded 10% in single-junction and 11% in multijunction devices. Despite these efforts, it is notoriously difficult to establish thorough structure-property relationships that will be required to further optimize existing high-performance polymers to their intrinsic limits. In this Account, we highlight progress on the development and our understanding of diketopyrrolopyrrole (DPP) based conjugated polymers for polymer solar cells. The DPP moiety is strongly electron withdrawing and its polar nature enhances the tendency of DPP-based polymers to crystallize. As a result, DPP-based conjugated polymers often exhibit an advantageously broad and tunable optical absorption, up to 1000 nm, and high mobilities for holes and electrons, which can result in high photocurrents and good fill factors in solar cells. Here we focus on the structural modifications applied to DPP polymers and rationalize and explain the relationships between chemical structure and organic photovoltaic performance. The DPP polymers can be tuned via their aromatic substituents, their alkyl side chains, and the nature of the π-conjugated segment linking the units along the polymer chain. We show that these building blocks work together in determining the molecular conformation, the optical properties, the charge carrier mobility, and the solubility of the polymer. We identify the latter as a decisive parameter for DPP-based organic solar cells because it regulates the diameter of the semicrystalline DPP polymer fibers that form in the photovoltaic blends with fullerenes via solution processing. The width of these fibers and the photon energy loss, defined as the energy difference between optical band gap and open-circuit voltage, together govern to a large extent the quantum efficiency for charge generation in these blends and thereby the power conversion efficiency of the photovoltaic devices. Lowering the photon energy loss and maintaining a high quantum yield for charge generation is identified as a major pathway to enhance the performance of organic solar cells. This can be achieved by controlling the structural purity of the materials and further control over morphology formation. We hope that this Account contributes to improved design strategies of DPP polymers that are required to realize new breakthroughs in organic solar cell performance in the future.

Rationale, design, and baseline characteristics of a community-based comparative effectiveness trial to prevent type 2 diabetes in economically disadvantaged adults: the RAPID Study.

PubMed

Ackermann, Ronald T; Finch, Emily A; Schmidt, Karen K; Hoen, Helena M; Hays, Laura M; Marrero, David G; Saha, Chandan

2014-01-01

Reaching Out and Preventing Increases in Diabetes (RAPID) is a community-based randomized trial evaluating the comparative costs and effectiveness of a group-based adaption of the DPP lifestyle intervention developed and implemented in partnership with the YMCA. RAPID enrolled adult primary care patients, with BMI 24 kg/m(2) or higher and abnormal glucose metabolism (HbA1c 5.7-6.9% or fasting plasma glucose 100-125 mg/dL). 509 participants were enrolled and randomized to one of two groups: standard clinical advice plus free-of-charge access to a group-based adaption of the DPP offered by the Y, versus standard clinical advice alone. Key outcomes for future analysis will include differences in body weight and other cardiovascular risk factors over a 24-month intervention period. At baseline, RAPID participants had a mean (SD) age of 51 ± 12.1 years, weight of 225.1 ± 56.2 lbs, and BMI of 36.9 ± 8.6 kg/m(2). 70.7% were women, 57.2% were African American, 35.4% were non-Hispanic White, and 3.2% were Hispanic. Mean HbA1c was 6.05 ± 0.34%. Additionally, 55.4% of participants had a baseline systolic blood pressure of ≥130 mmHg, 33.1% had a total blood cholesterol exceeding 200mg/dL, and 74% reported a household income of <$25,000. The RAPID Study successfully randomized a large cohort of participants with a wide distribution of age, body weight, and race who are at high risk for developing type 2 diabetes. © 2013.

Diketopyrrolopyrrole: brilliant red pigment dye-based fluorescent probes and their applications.

PubMed

Kaur, Matinder; Choi, Dong Hoon

2015-01-07

The development of fluorescent probes for the detection of biologically relevant species is a burgeoning topic in the field of supramolecular chemistry. A number of available dyes such as rhodamine, coumarin, fluorescein, and cyanine have been employed in the design and synthesis of new fluorescent probes. However, diketopyrrolopyrrole (DPP) and its derivatives have a distinguished role in supramolecular chemistry for the design of fluorescent dyes. DPP dyes offer distinctive advantages relative to other organic dyes, including high fluorescence quantum yields and good light and thermal stability. Significant advancements have been made in the development of new fluorescent probes based on DPP in recent years as a result of tireless research efforts by the chemistry scientific community. In this tutorial review, we highlight the recent progress in the development of DPP-based fluorescent probes for the period spanning 2009 to the present time and the applications of these probes to recognition of biologically relevant species including anions, cations, reactive oxygen species, thiols, gases and other miscellaneous applications. This review is targeted toward providing the readers with deeper understanding for the future design of DPP-based fluorogenic probes for chemical and biological applications.

MicroRNA-132 sensitizes nasopharyngeal carcinoma cells to cisplatin through regulation of forkhead box A1 protein.

PubMed

Li, Yun-Ling; Zhao, Yi-Gang; Chen, Bin; Li, Xiao-Feng

2016-12-01

Chemoresistance in cancer is one of the major hindrances in cisplatin (DPP) treatment for nasopharyngeal carcinoma (NPC). The mechanism of such resistance remains unknown. Therefore, the present study aimed to clarify the mechanism of DDP resistance and attempted to reduce chemoresistance. Here, we found that miR-132, as a tumor suppressor, was poorly expressed in a cisplatin resistant CNE2 cell line (CNE2/DPP) accompanied with a decreased expression of miR-132 and an increased expression of FOXA1 compared with the parental cells CNE2. Exogenous overexpression of miR-132 in CNE2/DPP could sensitize their reaction to the treatment of cisplatin. In addition, FOXA1 knockdown in CNE2/DPP cells increased the chemosensitivity to DPP, suggesting the dependence of FOXA1 regulation in miR-132 activity. Moreover, miR-132 can restore cisplatin treatment response in cisplatin-resistant xenografts in vivo, while FOXA1 protein levels were decreased. In summary, our results provide novel mechanistic insights into the role of miR-132/FOXA1 signaling in the cisplatin resistance of NPC cells. Targeting of miR-132 is a potential therapeutic approach for NPC.

The Downstart Program: a hospital-based pediatric healthy lifestyle program for obese and morbidly obese minority youth.

PubMed

Sternberg, Alex; Muzumdar, Hiren; Dinkevich, Eugene; Quintos, Jose Bernardo; Austin-Leon, Galia; Owens, Terrel; Murphy, Cheryl; Dapul, Geraldine; Rao, Madu

2006-12-01

Although obesity affects all cultures, ethnic groups and social strata, this disorder affects African Americans, Hispanics and the poor at a disproportionate rate. The Downstart Pediatric Healthy Lifestyle Program was developed to provide a multi-disciplinary behavioral modification program for inner city families in Brooklyn, New York interested in leading a healthier, more active lifestyle. The Downstart Program uses a four-pronged approach of medical evaluation, exercise, nutritional education and lifestyle modification. A psychological evaluation is performed to determine the individual's ability and readiness to participate in group activities. Baseline physical fitness, flexibility and muscle strength are measured, followed by a twice-weekly karate/martial arts/dance program, incorporating principles established by the President's Council on Exercise. Nutritional and behavioral modification aspects of the program consist of weekly education about food groups, portion control, goal setting and appropriate rewards for attaining goals. Our preliminary results indicate that the Downstart Program may be a viable intervention for weight loss. Further study is needed to improve strategies for motivating patients and means and criteria for assessing long-term effects on health and lifestyle.

Bar represses dPax2 and decapentaplegic to regulate cell fate and morphogenetic cell death in Drosophila eye.

PubMed

Kang, Jongkyun; Yeom, Eunbyul; Lim, Janghoo; Choi, Kwang-Wook

2014-01-01

The coordinated regulation of cell fate and cell survival is crucial for normal pattern formation in developing organisms. In Drosophila compound eye development, crystalline arrays of hexagonal ommatidia are established by precise assembly of diverse cell types, including the photoreceptor cells, cone cells and interommatidial (IOM) pigment cells. The molecular basis for controlling the number of cone and IOM pigment cells during ommatidial pattern formation is not well understood. Here we present evidence that BarH1 and BarH2 homeobox genes are essential for eye patterning by inhibiting excess cone cell differentiation and promoting programmed death of IOM cells. Specifically, we show that loss of Bar from the undifferentiated retinal precursor cells leads to ectopic expression of Prospero and dPax2, two transcription factors essential for cone cell specification, resulting in excess cone cell differentiation. We also show that loss of Bar causes ectopic expression of the TGFβ homolog Decapentaplegic (Dpp) posterior to the morphogenetic furrow in the larval eye imaginal disc. The ectopic Dpp expression is not responsible for the formation of excess cone cells in Bar loss-of-function mutant eyes. Instead, it causes reduction in IOM cell death in the pupal stage by antagonizing the function of pro-apoptotic gene reaper. Taken together, this study suggests a novel regulatory mechanism in the control of developmental cell death in which the repression of Dpp by Bar in larval eye disc is essential for IOM cell death in pupal retina.

Active for Life After Cancer: a randomized trial examining a lifestyle physical activity program for prostate cancer patients.

PubMed

Carmack Taylor, Cindy L; Demoor, Carl; Smith, Murray A; Dunn, Andrea L; Basen-Engquist, Karen; Nielsen, Ingrid; Pettaway, Curtis; Sellin, Rena; Massey, Pamela; Gritz, Ellen R

2006-10-01

Active for Life After Cancer is a randomized trial evaluating the efficacy of a 6-month group-based lifestyle physical activity program (Lifestyle) for prostate cancer patients to improve quality of life (QOL) including physical and emotional functioning compared to a group-based Educational Support Program and a Standard Care Program (no group). A total of 134 prostate cancer patients receiving continuous androgen-ablation were randomly assigned to one of the three study conditions. Results indicated no significant improvements in QOL at 6 or 12 months. Both group-based programs were positively received and yielded good attendance and retention. Lifestyle participants demonstrated significant improvements in most theoretical mediators proposed by the Transtheoretical Model and Social Cognitive Theory to affect physical activity. Despite these improvements, no significant changes were found for most physical activity measures. Results suggest a lifestyle program focusing on cognitive-behavioral skills training alone is insufficient for promoting routine physical activity in these patients.

Effectiveness and safety of dipeptidyl peptidase 4 inhibitors in the management of type 2 diabetes in older adults: a systematic review and development of recommendations to reduce inappropriate prescribing.

PubMed

Schott, Gisela; Martinez, Yolanda V; Ediriweera de Silva, R Erandie; Renom-Guiteras, Anna; Vögele, Anna; Reeves, David; Kunnamo, Ilkka; Marttila-Vaara, Minna; Sönnichsen, Andreas

2017-10-16

Preventable drug-related hospital admissions can be associated with drugs used in diabetes and the benefits of strict diabetes control may not outweigh the risks, especially in older populations. The aim of this study was to look for evidence on risks and benefits of DPP-4 inhibitors in older adults and to use this evidence to develop recommendations for the electronic decision support tool of the PRIMA-eDS project. Systematic review using a staged approach which searches for systematic reviews and meta-analyses first, then individual studies only if prior searches were inconclusive. The target population were older people (≥65 years old) with type 2 diabetes. We included studies reporting on the efficacy and/or safety of DPP-4 inhibitors for the management of type 2 diabetes. Studies were included irrespective of DPP-4 inhibitors prescribed as monotherapy or in combination with any other drug for the treatment of type 2 diabetes. The target intervention was DPP-4 inhibitors compared to placebo, no treatment, other drugs to treat type 2 diabetes or a non-pharmacological intervention. Thirty studies (reported in 33 publications) were included: 1 meta-analysis, 17 intervention studies and 12 observational studies. Sixteen studies were focused on older adults and 14 studies reported subgroup analyses in participants ≥65, ≥70, or ≥75 years. Comorbidities were reported by 26 studies and frailty or functional status by one study. There were conflicting findings regarding the effectiveness of DPP-4 inhibitors in older adults. In general, DPP-4 inhibitors showed similar or better safety than placebo and other antidiabetic drugs. However, these safety data are mainly based on short-term outcomes like hypoglycaemia in studies with HbA1c control levels recommended for younger people. One recommendation was developed advising clinicians to reconsider the use of DPP-4 inhibitors for the management of type 2 diabetes in older adults with HbA1c <8.5% because of scarce data on clinically relevant benefits of their use. Twenty-two of the included studies were funded by pharmaceutical companies and authored or co-authored by employees of the sponsor. Other than the surrogate endpoint of improved glycaemic control, data on clinically relevant benefits of DPP-4 inhibitors in the treatment of type 2 diabetes mellitus in older adults is scarce. DPP-4 inhibitors might have a lower risk of hypoglycaemia compared to other antidiabetic drugs but data show conflicting findings for long-term benefits. Further studies are needed that evaluate the risks and benefits of DPP-4 inhibitors for the management of type 2 diabetes mellitus in older adults, using clinically relevant outcomes and including representative samples of older adults with information on their frailty status and comorbidities. Studies are also needed that are independent of pharmaceutical company involvement.

Risk of hospitalization for heart failure in patients with type 2 diabetes newly treated with DPP-4 inhibitors or other oral glucose-lowering medications: a retrospective registry study on 127,555 patients from the Nationwide OsMed Health-DB Database.

PubMed

Fadini, Gian Paolo; Avogaro, Angelo; Degli Esposti, Luca; Russo, Pierluigi; Saragoni, Stefania; Buda, Stefano; Rosano, Giuseppe; Pecorelli, Sergio; Pani, Luca

2015-09-21

Oral glucose-lowering medications are associated with excess risk of heart failure (HF). Given the absence of comparative data among drug classes, we performed a retrospective study in 32 Health Services of 16 Italian regions accounting for a population of 18 million individuals, to assess the association between HF risk and use of sulphonylureas, DPP-4i, and glitazones. We extracted data on patients with type 2 diabetes who initiated treatment with DPP-4i, thiazolidinediones, or sulphonylureas alone or in combination with metformin during an accrual time of 2 years. The endpoint was hospitalization for HF (HHF) occurring after the first 6 months of therapy, and the observation was extended for up to 4 years. A total of 127 555 patients were included, of whom 14.3% were on DPP-4i, 72.5% on sulphonylurea, 13.2% on thiazolidinediones, with average 70.7% being on metformin as combination therapy. Patients in the three groups differed significantly for baseline characteristics: age, sex, Charlson index, concurrent medications, and previous cardiovascular events. During an average 2.6-year follow-up, after adjusting for measured confounders, use of DPP-4i was associated with a reduced risk of HHF compared with sulphonylureas [hazard ratio (HR) 0.78; 95% confidence interval (CI) 0.62-0.97; P = 0.026]. After propensity matching, the analysis was restricted to 39 465 patients, and the use of DPP-4i was still associated with a lower risk of HHF (HR 0.70; 95% CI 0.52-0.94; P = 0.018). In a very large observational study, the use of DPP-4i was associated with a reduced risk of HHF when compared with sulphonylureas. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

Localization and expression of Orexin A and its receptor in mouse testis during different stages of postnatal development.

PubMed

Joshi, Deepanshu; Singh, Shio Kumar

2017-01-15

Orexin A (OXA), a hypothalamic neuropeptide, is involved in regulation of various biological functions and its actions are mediated through G-protein-coupled receptor, OX1R. This neuropeptide has emerged as a central neuroendocrine modulator of reproductive functions. Both OXA and OX1R have been shown to be expressed in peripheral organs such as gastrointestinal and genital tracts. In the present study, localization and expression of OXA and OX1R in mouse testis during different stages of postnatal development have been investigated. Immunohistochemical results demonstrated localization of OXA and OX1R in both the interstitial and the tubular compartments of the testis throughout the period of postnatal development. In testicular sections on 0day postpartum (dpp), gonocytes, Sertoli cells and foetal Leydig cells showed OXA and OX1R-immunopositive signals. At 10dpp, Sertoli cells, spermatogonia, early spermatocytes and Leydig cells showed immunopositive signals for both, the ligand and the receptor. On 30 and 90dpp, the spermatogonia, Sertoli cells, spermatocytes, spermatids and Leydig cells showed the OXA and OX1R-immunopositive signals. At 90dpp, strong OXA-positive signals were seen in Leydig cells, primary spermatocytes and spermatogonia, while OX1R-immunopositive intense signals were observed in Leydig cells and elongated spermatids. Further, semiquantitative RT-PCR and immunoblot analyses showed that OXA and OX1R were expressed in the testis both at transcript and protein levels during different stages of postnatal development. The expression of OXA and OX1R increased progressively from day of birth (0dpp) until adulthood (90dpp), with maximal expression at 90 dpp. The results suggest that OXA and OX1R are expressed in the testis and that they may help in proliferation and development of germ cells, Leydig cells and Sertoli cells, and in the spermatogenic process and steroidogenesis. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of Inhibiting Dipeptidyl Peptidase-4 (DPP4) in Cows with Subclinical Ketosis.

PubMed

Schulz, Kirsten; Frahm, Jana; Kersten, Susanne; Meyer, Ulrich; Rehage, Jürgen; Piechotta, Marion; Meyerholz, Maria; Breves, Gerhard; Reiche, Dania; Sauerwein, Helga; Dänicke, Sven

2015-01-01

The inhibition of dipeptidyl peptidase-4 (DPP4) via specific inhibitors is known to result in improved glucose tolerance and insulin sensitivity and decreased accumulation of hepatic fat in type II diabetic human patients. The metabolic situation of dairy cows can easily be compared to the status of human diabetes and non-alcoholic fatty liver. For both, insulin sensitivity is reduced, while hepatic fat accumulation increases, characterized by high levels of non-esterified fatty acids (NEFA) and ketone bodies.Therefore, in the present study, a DPP4 inhibitor was employed (BI 14332) for the first time in cows. In a first investigation BI 14332 treatment (intravenous injection at dosages of up to 3 mg/kg body weight) was well tolerated in healthy lactating pluriparous cows (n = 6) with a significant inhibition of DPP4 in plasma and liver. Further testing included primi- and pluriparous lactating cows suffering from subclinical ketosis (β-hydroxybutyrate concentrations in serum > 1.2 mM; n = 12). The intension was to offer effects of DPP4 inhibition during comprehensive lipomobilisation and hepatosteatosis. The cows of subclinical ketosis were evenly allocated to either the treatment group (daily injections, 0.3 mg BI 14332/kg body weight, 7 days) or the control group. Under condition of subclinical ketosis, the impact of DPP4 inhibition via BI 14332 was less, as in particular β-hydroxybutyrate and the hepatic lipid content remained unaffected, but NEFA and triglyceride concentrations were decreased after treatment. Owing to lower NEFA, the revised quantitative insulin sensitivity check index (surrogate marker for insulin sensitivity) increased. Therefore, a positive influence on energy metabolism might be quite possible. Minor impacts on immune-modulating variables were limited to the lymphocyte CD4+/CD8+ ratio for which a trend to decreased values in treated versus control animals was noted. In sum, the DPP4 inhibition in cows did not affect glycaemic control like it is shown in humans, but was able to impact hyperlipemia, as NEFA and TG decreased.

Exploring the reach and program use of Hello World, an email-based health promotion program for pregnant women in the Netherlands.

PubMed

van Dongen, Johanna M; van Poppel, Mireille N M; Milder, Ivon E J; van Oers, Hans A M; Brug, Johannes

2012-09-22

In 2006, the Dutch government initiated Hello World, an email-based program promoting healthy lifestyles among pregnant women through quizzes with pregnancy-related questions. In 2008, an updated version was released.The present study aimed to (1) examine the reach of Hello World and the representativeness of its users for all pregnant women in the Netherlands, (2) explore the relationship between program engagement and lifestyle characteristics, and (3) explore the relationship between the program content participants accessed (content on smoking, physical activity, and nutrition) and their lifestyle characteristics. Data from 4,363 pregnant women were included. After registration, women received an online questionnaire with demographic and lifestyle questions. To evaluate their representativeness, their demographic characteristics were compared with existing data for Dutch (pregnant) women. Women were classified on the following lifestyle characteristics: smoking, nutrition, physical activity, and pre-pregnancy weight status. Program use was tracked and the relationships between lifestyle characteristics, program engagement, and the percentage of smoking, physical activity, and nutrition questions accessed after opening a quiz were explored using Mann-Whitney U tests and Kruskal-Wallis tests. Hello World reached ±4% of its target population. Ten percent of participants were low educated and 22% immigrants. On average, women received 6.1 (SD:2.8) quiz emails and opened 32% of the associated quizzes (2.0, SD:2.1). A significant positive association was found between the number of quizzes opened and the number of healthy lifestyle characteristics. After opening a quiz, women accessed most smoking, nutrition, and physical activity questions. Significant relationships were found between several lifestyle characteristics and the percentage of smoking, physical activity, and nutrition questions accessed. However, between-group differences were small, quiz topics were largely unrelated to their lifestyle characteristics, and inconsistencies were found regarding the directions of these associations. Hello World reached ±4% of its target population, which is lower than the reach of its previous version (±8%). Relatively few low educated and immigrant women registered for the program. Active participation in the program was positively associated with the number of healthy behaviours participants engaged in. The program content participants chose to access was largely unrelated to their lifestyle characteristics.

DPP-4 Inhibitors: Incretin-Based Medicine for Type 2 Diabetes

MedlinePlus

... medicines? DPP-4 inhibitor medicines (generic names: sitagliptin saxagliptin, and linagliptin) are a type of incretin-based ... of diabetes medicine. Your dose of sitagliptin or saxagliptin (but not linagliptin) may need to be adjusted ...

Comparative Analysis of Binding Kinetics and Thermodynamics of Dipeptidyl Peptidase-4 Inhibitors and Their Relationship to Structure.

PubMed

Schnapp, Gisela; Klein, Thomas; Hoevels, Yvette; Bakker, Remko A; Nar, Herbert

2016-08-25

The binding kinetics and thermodynamics of dipeptidyl peptidase (DPP)-4 inhibitors (gliptins) were investigated using surface plasmon resonance and isothermal titration calorimetry. Binding of gliptins to DPP-4 is a rapid electrostatically driven process. Off-rates were generally slow partly because of reversible covalent bond formation by some gliptins, and partly because of strong and extensive interactions. Binding of all gliptins is enthalpy-dominated due to strong ionic interactions and strong solvent-shielded hydrogen bonds. Using a congeneric series of molecules which represented the intermediates in the lead optimization program of linagliptin, the onset of slow binding kinetics and development of the thermodynamic repertoire were analyzed in the context of incremental changes of the chemical structures. All compounds rapidly associated, and therefore the optimization of affinity and residence time is highly correlated. The major contributor to the increasing free energy of binding was a strong increase of binding enthalpy, whereas entropic contributions remained low and constant despite significant addition of lipophilicity.

Design Effectiveness Analysis of a Media Literacy Intervention to Reduce Violent Video Games Consumption Among Adolescents: The Relevance of Lifestyles Segmentation.

PubMed

Rivera, Reynaldo; Santos, David; Brändle, Gaspar; Cárdaba, Miguel Ángel M

2016-04-01

Exposure to media violence might have detrimental effects on psychological adjustment and is associated with aggression-related attitudes and behaviors. As a result, many media literacy programs were implemented to tackle that major public health issue. However, there is little evidence about their effectiveness. Evaluating design effectiveness, particularly regarding targeting process, would prevent adverse effects and improve the evaluation of evidence-based media literacy programs. The present research examined whether or not different relational lifestyles may explain the different effects of an antiviolence intervention program. Based on relational and lifestyles theory, the authors designed a randomized controlled trial and applied an analysis of variance 2 (treatment: experimental vs. control) × 4 (lifestyle classes emerged from data using latent class analysis: communicative vs. autonomous vs. meta-reflexive vs. fractured). Seven hundred and thirty-five Italian students distributed in 47 classes participated anonymously in the research (51.3% females). Participants completed a lifestyle questionnaire as well as their attitudes and behavioral intentions as the dependent measures. The results indicated that the program was effective in changing adolescents' attitudes toward violence. However, behavioral intentions toward consumption of violent video games were moderated by lifestyles. Those with communicative relational lifestyles showed fewer intentions to consume violent video games, while a boomerang effect was found among participants with problematic lifestyles. Adolescents' lifestyles played an important role in influencing the effectiveness of an intervention aimed at changing behavioral intentions toward the consumption of violent video games. For that reason, audience lifestyle segmentation analysis should be considered an essential technique for designing, evaluating, and improving media literacy programs. © The Author(s) 2016.

Development and Evaluation of a Mobile Application for Personal Lifestyle Check-Up and Improvement

PubMed Central

Youm, Sekyoung

2014-01-01

Abstract Objective: This study aimed (1) to help individuals analyze their own health status by checking their lifestyle, (2) to develop a user-friendly mobile application that offered prescriptions for lifestyle improvement, and (3) to examine whether the developed application had positive effects on users. Materials and Methods: In order to develop a lifestyle analysis engine that would operate in an Android® (Google, Mountain View, CA)-based mobile application, survey data on health awareness behaviors of 25,124 participants from the 2009 Korean National Health and Nutrition Examination Survey (KNHANES) were analyzed. Additionally, in order for the users to be aware of their lifestyles and explore the effects of the developed mobile application on lifestyle management and improvement, an additional survey of the lifestyle awareness and levels of motivation for lifestyle improvement of 152 users was conducted. Results: The differences between lifestyles before and after using the application were examined. A paired t test was used for questions regarding (1) the level of motivation to improve lifestyles and (2) changes in lifestyle. The lifestyle score was lower after using the program than before using it. Conversely, the level of motivation to improve lifestyle was greater after the program than before it. Both results were statistically significant. Conclusions: By using the KNHANES, this study developed a mobile application that compared the quantified lifestyles of individuals and enabled individuals to check easily their health statuses, whenever and wherever necessary. The program developed in this study contributed to motivating individuals to be aware of and to improve their lifestyles. PMID:25384255

Development and evaluation of a mobile application for personal lifestyle check-up and improvement.

PubMed

Youm, Sekyoung; Park, Seung-Hun

2014-11-01

This study aimed (1) to help individuals analyze their own health status by checking their lifestyle, (2) to develop a user-friendly mobile application that offered prescriptions for lifestyle improvement, and (3) to examine whether the developed application had positive effects on users. In order to develop a lifestyle analysis engine that would operate in an Android(®) (Google, Mountain View, CA)-based mobile application, survey data on health awareness behaviors of 25,124 participants from the 2009 Korean National Health and Nutrition Examination Survey (KNHANES) were analyzed. Additionally, in order for the users to be aware of their lifestyles and explore the effects of the developed mobile application on lifestyle management and improvement, an additional survey of the lifestyle awareness and levels of motivation for lifestyle improvement of 152 users was conducted. The differences between lifestyles before and after using the application were examined. A paired t test was used for questions regarding (1) the level of motivation to improve lifestyles and (2) changes in lifestyle. The lifestyle score was lower after using the program than before using it. Conversely, the level of motivation to improve lifestyle was greater after the program than before it. Both results were statistically significant. By using the KNHANES, this study developed a mobile application that compared the quantified lifestyles of individuals and enabled individuals to check easily their health statuses, whenever and wherever necessary. The program developed in this study contributed to motivating individuals to be aware of and to improve their lifestyles.

Lipid, lipoproteins, C-reactive protein, and hemostatic factors at baseline in the diabetes prevention program.

PubMed

2005-10-01

Individuals with impaired glucose tolerance (IGT) appear to be at increased risk for cardiovascular disease (CVD) due at least in part to an increased prevalence of risk factors. We evaluated lipid, lipoprotein, C-reactive protein (CRP), fibrinogen, and tissue plasminogen activator (tPA) levels at study entry in the largest multiethnic cohort of participants with IGT described, namely in the Diabetes Prevention Program (DPP). Measurements were performed at the baseline visit of 3,819 randomized participants of the DPP. Among 3,622 participants who were not taking lipid-lowering medicines, cardiovascular risk factors were analyzed in relation to demographic, anthropometric, and metabolic measures. Major determinants of risk factors were assessed in multivariate analysis. Over 40% of participants had elevated triglyceride, LDL cholesterol, and CRP levels and reduced HDL cholesterol levels. Men had higher triglyceride and tPA and lower HDL cholesterol concentrations and smaller LDL particle size than women, whereas women had higher CRP and fibrinogen levels. African Americans had less dyslipidemia but higher fibrinogen levels, and Asian Americans had lower CRP and fibrinogen levels than Caucasians and Hispanics. The surrogate measure of insulin resistance (homeostasis model assessment of insulin resistance [HOMA-IR]) had the strongest association with HDL cholesterol, triglyceride, and tPA levels and LDL particle size. BMI had the greatest influence on CRP and fibrinogen levels. Using median splits of indexes of insulin resistance and insulin secretion (insulin-to-glucose ratio), participants with greater insulin resistance had a more adverse CVD risk-factor profile, whereas insulin secretion had little influence on risk factors. The pattern of CVD risk factors in participants with IGT in the DPP exhibits substantial heterogeneity and is significantly influenced by race, sex, and age, as well as by obesity, glucose, and insulin measures. The degree of insulin resistance, as reflected by HOMA-IR, showed the greatest association with the cardiovascular risk factors.

Lipid, Lipoproteins, C-Reactive Protein, and Hemostatic Factors at Baseline in the Diabetes Prevention Program

PubMed Central

2005-01-01

OBJECTIVE — Individuals with impaired glucose tolerance (IGT) appear to be at increased risk for cardiovascular disease (CVD) due at least in part to an increased prevalence of risk factors. We evaluated lipid, lipoprotein, C-reactive protein (CRP), fibrinogen, and tissue plasminogen activator (tPA) levels at study entry in the largest multiethnic cohort of participants with IGT described, namely in the Diabetes Prevention Program (DPP). RESEARCH DESIGN AND METHODS — Measurements were performed at the baseline visit of 3,819 randomized participants of the DPP. Among 3,622 participants who were not taking lipid-lowering medicines, cardiovascular risk factors were analyzed in relation to demographic, anthropometric, and metabolic measures. Major determinants of risk factors were assessed in multivariate analysis. RESULTS — Over 40% of participants had elevated triglyceride, LDL cholesterol, and CRP levels and reduced HDL cholesterol levels. Men had higher triglyceride and tPA and lower HDL cholesterol concentrations and smaller LDL particle size than women, whereas women had higher CRP and fibrinogen levels. African Americans had less dyslipidemia but higher fibrinogen levels, and Asian Americans had lower CRP and fibrinogen levels than Caucasians and Hispanics. The surrogate measure of insulin resistance (homeostasis model assessment of insulin resistance [HOMA-IR]) had the strongest association with HDL cholesterol, triglyceride, and tPA levels and LDL particle size. BMI had the greatest influence on CRP and fibrinogen levels. Using median splits of indexes of insulin resistance and insulin secretion (insulin-to-glucose ratio), participants with greater insulin resistance had a more adverse CVD risk-factor profile, whereas insulin secretion had little influence on risk factors. CONCLUSIONS — The pattern of CVD risk factors in participants with IGT in the DPP exhibits substantial heterogeneity and is significantly influenced by race, sex, and age, as well as by obesity, glucose, and insulin measures. The degree of insulin resistance, as reflected by HOMA-IR, showed the greatest association with the cardiovascular risk factors. PMID:16186282

Mineralization induction effects of osteopontin, bone sialoprotein, and dentin phosphoprotein on a biomimetic collagen substrate.

PubMed

Zurick, Kevin M; Qin, Chunlin; Bernards, Matthew T

2013-06-01

Native bone tissue is composed of a matrix of collagen, noncollagenous proteins, and calcium phosphate minerals, which are primarily hydroxyapatite. The SIBLING (small integrin-binding ligand, N-linked glycoprotein) family of proteins is the primary noncollagenous protein group found in mineralized tissues. In this work, the mineralization induction capabilities of three of the SIBLING members, bone sialoprotein (BSP), osteopontin (OPN), and the calcium-binding subdomain of dentin sialophosphoprotein, dentin phosphoprotein (DPP), are directly compared on a biomimetic collagen substrate. A self-assembled, loosely aligned collagen fibril substrate was prepared, and then (125) I-radiolabeled adsorption isotherms were developed for BSP, OPN, and DPP. The results showed that BSP exhibited the highest binding capacity for collagen at lower concentrations, followed by DPP and OPN. However, at the highest concentrations, all three proteins had similar adsorption levels. The adsorption isotherms were then used to identify conditions that resulted in identical amounts of adsorbed protein. These substrates were prepared and placed in simulated body fluid for 5, 10, and 24 h at 37°C. The resulting mineral morphology was assessed by atomic force microscopy, and the composition was determined using photochemical assays. Mineralization was seen in the presence of all the proteins. However, DPP was seen to be the only protein that formed individual mineral nodules similar to those seen in developing bone. This suggests that DPP plays a significant role in the biomineralization process and that the incorporation of DPP into tissue engineering constructs may facilitate the induction of biomimetic mineral formation. Copyright © 2012 Wiley Periodicals, Inc.

Mineralization Induction Effects of Osteopontin, Bone Sialoprotein, and Dentin Phosphoprotein on a Biomimetic Collagen Substrate

PubMed Central

Zurick, Kevin M.; Qin, Chunlin; Bernards, Matthew T.

2012-01-01

Native bone tissue is composed of a matrix of collagen, non-collagenous proteins, and calcium phosphate minerals, which are primarily hydroxyapatite (HA). The SIBLING (small integrin-binding ligand, N-linked glycoprotein) family of proteins is the primary non-collagenous protein group found in mineralized tissues. In this work, the mineralization induction capabilities of three of the SIBLING members, bone sialoprotein (BSP), osteopontin (OPN), and the calcium binding subdomain of dentin sialophosphoprotein, dentin phosphoprotein (DPP), are directly compared on a biomimetic collagen substrate. A self-assembled, loosely aligned collagen fibril substrate was prepared and then 125I radiolabeled adsorption isotherms were developed for BSP, OPN, and DPP. The results showed that BSP exhibited the highest binding capacity for collagen at lower concentrations, followed by DPP and OPN. However, at the highest concentrations all three proteins had similar adsorption levels. The adsorption isotherms were then used to identify conditions that resulted in identical amounts of adsorbed protein. These substrates were prepared and placed in simulated body fluid for 5 hours, 10 hours, and 24 hours at 37°C. The resulting mineral morphology was assessed by atomic force microscopy and the composition was determined using photochemical assays. Mineralization was seen in the presence of all of the proteins. However, DPP was seen to be the only protein that formed individual mineral nodules similar to those seen in developing bone. This suggests that DPP plays a significant role in the biomineralization process and that the incorporation of DPP into tissue engineering constructs may facilitate the induction of biomimetic mineral formation. PMID:23161527

Dipeptidyl peptidase-II from probiotic Pediococcus acidilactici: Purification and functional characterization.

PubMed

Gandhi, Dimpi; Chanalia, Preeti; Attri, Pooja; Dhanda, Suman

2016-12-01

Dipeptidylpeptidase-II (DPP-II, E.C. 3.4.14.2), an exopeptidase was purified 15.4 fold with specific activity and yield of 15.4U/mg/mL and 14.68% respectively by a simple two step procedure from a probiotic Pediococcus acidilactici. DPP-II is 38.7KDa homodimeric serine peptidase with involvement of His and subunit mass of 18.9KDa. The enzyme exhibited optimal activity at pH 7.0 and 37°C with activation energy of 24.97kJ/mol. The enzyme retained more than 90% activity upto 50°C thus adding industrial importance. DPP-II hydrolysed Lys-Ala-4mβNA with K M of 50μM and V max of 30.8nmol/mL/min. In-silico characterization studies of DPP-II on the basis of peptide fragments obtained by MALDI-TOF revealed an evolutionary relationship between DPP-II of prokaryotes and phosphate binding proteins. Secondary and three-dimensional structure of enzyme was also deduced by in-silico approach. Functional studies of DPP-II by TLC and HPLC-analysis of collagen degraded products revealed that enzyme action released free amino acids and other metabolites. Microscopic and SDS-PAGE analysis of enzyme treated analysis of chicken's chest muscle (meat) hydrolysis revealed change and hydrolysis of myofibrils. This may affect the flavor and texture of meat thereby suggesting its role in meat tenderization. Being a protein of LAB (Lactic acid bacteria), it is also expected to be safe. Copyright © 2016 Elsevier B.V. All rights reserved.

Automatic algorithm for monitoring systolic pressure variation and difference in pulse pressure.

PubMed

Pestel, Gunther; Fukui, Kimiko; Hartwich, Volker; Schumacher, Peter M; Vogt, Andreas; Hiltebrand, Luzius B; Kurz, Andrea; Fujita, Yoshihisa; Inderbitzin, Daniel; Leibundgut, Daniel

2009-06-01

Difference in pulse pressure (dPP) reliably predicts fluid responsiveness in patients. We have developed a respiratory variation (RV) monitoring device (RV monitor), which continuously records both airway pressure and arterial blood pressure (ABP). We compared the RV monitor measurements with manual dPP measurements. ABP and airway pressure (PAW) from 24 patients were recorded. Data were fed to the RV monitor to calculate dPP and systolic pressure variation in two different ways: (a) considering both ABP and PAW (RV algorithm) and (b) ABP only (RV(slim) algorithm). Additionally, ABP and PAW were recorded intraoperatively in 10-min intervals for later calculation of dPP by manual assessment. Interobserver variability was determined. Manual dPP assessments were used for comparison with automated measurements. To estimate the importance of the PAW signal, RV(slim) measurements were compared with RV measurements. For the 24 patients, 174 measurements (6-10 per patient) were recorded. Six observers assessed dPP manually in the first 8 patients (10-min interval, 53 measurements); no interobserver variability occurred using a computer-assisted method. Bland-Altman analysis showed acceptable bias and limits of agreement of the 2 automated methods compared with the manual method (RV: -0.33% +/- 8.72% and RV(slim): -1.74% +/- 7.97%). The difference between RV measurements and RV(slim) measurements is small (bias -1.05%, limits of agreement 5.67%). Measurements of the automated device are comparable with measurements obtained by human observers, who use a computer-assisted method. The importance of the PAW signal is questionable.

Germline Proliferation Is Regulated by Somatic Endocytic Genes via JNK and BMP Signaling in Drosophila.

PubMed

Tang, Yaning; Geng, Qing; Chen, Di; Zhao, Shaowei; Liu, Xian; Wang, Zhaohui

2017-05-01

Signals derived from the microenvironment contribute greatly to tumorigenesis . The underlying mechanism requires thorough investigation. Here, we use Drosophila testis as a model system to address this question, taking the advantage of the ease to distinguish germline and somatic cells and to track the cell numbers. In an EMS mutagenesis screen, we identified Rab5 , a key factor in endocytosis, for its nonautonomous role in germline proliferation. The disruption of Rab5 in somatic cyst cells, which escort the development of germline lineage, induced the overproliferation of underdifferentiated but genetically wild-type germ cells. We demonstrated that this nonautonomous effect was mediated by the transcriptional activation of Dpp [the fly homolog of bone morphogenetic protein (BMP)] by examining the Dpp-reporter expression and knocking down Dpp to block germline overgrowth. Consistently, the protein levels of Bam, the germline prodifferentiation factor normally accumulated in the absence of BMP/Dpp signaling, decreased in the overproliferating germ cells. Further, we discovered that the JNK signaling pathway operated between Rab5 and Dpp, because simultaneously inhibiting the JNK pathway and Rab5 in cyst cells prevented both dpp transcription and germline tumor growth. Additionally, we found that multiple endocytic genes, such as avl , TSG101 , Vps25 , or Cdc42 , were required in the somatic cyst cells to restrict germline amplification. These findings indicate that when the endocytic state of the surrounding cells is impaired, genetically wild-type germ cells overgrow. This nonautonomous model of tumorigenesis provides a simple system to dissect the relation between tumor and its niche. Copyright © 2017 by the Genetics Society of America.

CD26 modulates nociception in mice via its dipeptidyl-peptidase IV activity.

PubMed

Guieu, Regis; Fenouillet, Emmanuel; Devaux, Christiane; Fajloun, Ziad; Carrega, Louis; Sabatier, Jean-Marc; Sauze, Nicole; Marguet, Didier

2006-01-30

CD26 is a multifunctional cell surface glycoprotein expressed by T and B cells. It exhibits a dipeptidyl-peptidase activity (DPP-IV) that cleaves the penultimate proline from the N-terminus of polypeptides, thereby regulating their activity and concentration. Using CD26-/- mice resulting from targeted inactivation of the gene, we examined the consequences of a DPP-IV defect on behavioural response to nociceptive stimuli and concentration of the pain modulator peptides substance P (SP) and endomorphin 2, two DPP-IV substrates. CD26 inactivation induced a three-fold decrease in circulating endopeptidase activity while that found in brain extracts was normal, albeit very weak. CD26-/- mice had high SP concentrations in plasma (3.4+/-1 pg/ml versus 1.5+/-0.3 pg/ml, P<10(-3)) but not in brain extracts (35+/-12 pg/ml versus 32+/-9 pg/ml, P>0.05). Endomorphin-2 levels in the two groups were in the same range for plasma and brain extracts. CD26-/- mice displayed short latencies to nociceptive stimuli (hot plate test: 6.6+/-1.2 s versus 8.6+/-1.5 s, P<10(-4); tail pinch test: 3.1+/-0.6 s versus 4.2+/-0.8 s, P<10(-3)). Administration of an SP (NK1) receptor antagonist or DPP-IV to CD26-/- mice normalised latencies. DPP-IV inhibitors decreased latencies only in CD26+/+ mice. Our observations represent the first fundamental evidence showing that DPP-IV influences pain perception via modulation of the peripheral SP concentration. Our work also highlights the role of peripheral NK1 receptors in nociception.

Dipeptidyl Peptidase-4 Inhibitor-Associated Pancreatic Carcinoma: A Review of the FAERS Database.

PubMed

Nagel, Angela K; Ahmed-Sarwar, Nabila; Werner, Paul M; Cipriano, Gabriela C; Van Manen, Robbert P; Brown, Jack E

2016-01-01

To date, there is limited literature regarding the association between dipeptidyl peptidase-4 (DPP-4) inhibitors and pancreatic carcinoma. To describe the comparative incidence of DPP-4 inhibitors and pancreatic carcinoma as reportedly available in the Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) database. The goal was to provide health care practitioners a general understanding of the drug-disease occurrence. This is a case/noncase study utilizing Empirica Signal software to query FAERS from November 1968 to December 31, 2013. The software was used to calculate a disproportionality statistic--namely, the empirical Bayesian geometric mean (EBGM)--for reports of DPP-4 inhibitors-associated pancreatic carcinoma. The FDA considers an EBGM significant if the fifth percentile of the distribution is at least 2, defined as an EB05 ≥ 2. With use of a disproportionality analysis, DPP-4 inhibitors were compared with all agents listed in FAERS. A total of 156 patients experienced pancreatic carcinoma while receiving DPP-4 inhibitor therapy. An EB05 of 10.3 was determined for sitagliptin, 7.1 for saxagliptin, 4.9 for linagliptin, and 1.4 for alogliptin, compared with all other agents included in FAERS. Although an EB05 > 2 was achieved in 2 other antihyperglycemic agents, the findings were not consistent within their medication classes. There appears to be a statistical association between DPP-4 inhibitor use and pancreatic carcinoma. Causality cannot be inferred from the data provided. Additional clinical studies are needed to further explore this statistical association. © The Author(s) 2015.

Implementation of Lifestyle Modification Program Focusing on Physical Activity and Dietary Habits in a Large Group, Community-Based Setting.

PubMed

Stoutenberg, Mark; Falcon, Ashley; Arheart, Kris; Stasi, Selina; Portacio, Francia; Stepanenko, Bryan; Lan, Mary L; Castruccio-Prince, Catarina; Nackenson, Joshua

2017-06-01

Lifestyle modification programs improve several health-related behaviors, including physical activity (PA) and nutrition. However, few of these programs have been expanded to impact a large number of individuals in one setting at one time. Therefore, the purpose of this study was to determine whether a PA- and nutrition-based lifestyle modification program could be effectively conducted using a large group format in a community-based setting. One hundred twenty-one participants enrolled in a 16-week, community-based lifestyle modification program and separated in small teams of 13 to 17 individuals. Height, weight, fruit and vegetable (FAV) consumption, physical fitness, and several psychosocial measures were assessed before and after the program. Significant improvements in 6-minute walk distance (+68.3 m; p < .001), chair stands (+6.7 repetitions; p < .001), FAV servings (+1.8 servings/day; p < .001), body weight (-3.2 lbs; p < .001), as well as PA social support and eating habits self-efficacy were observed. Our lifestyle modification program was also successful in shifting participants to higher levels of stages of change for nutrition and PA, increasing overall levels of self-efficacy for healthy eating, and improving levels of social support for becoming more active. A lifestyle modification program can be successfully implemented in a community setting using a large group format to improve PA and FAV attitudes and behaviors.

Electrochemical, spectroscopic, and photophysical properties of structurally diverse polyazine-bridged Ru(II),Pt(II) and Os(II),Ru(II),Pt(II) supramolecular motifs.

PubMed

Knoll, Jessica D; Arachchige, Shamindri M; Wang, Guangbin; Rangan, Krishnan; Miao, Ran; Higgins, Samantha L H; Okyere, Benjamin; Zhao, Meihua; Croasdale, Paul; Magruder, Katherine; Sinclair, Brian; Wall, Candace; Brewer, Karen J

2011-09-19

Five new tetrametallic supramolecules of the motif [{(TL)(2)M(dpp)}(2)Ru(BL)PtCl(2)](6+) and three new trimetallic light absorbers [{(TL)(2)M(dpp)}(2)Ru(BL)](6+) (TL = bpy = 2,2'-bipyridine or phen = 1,10-phenanthroline; M = Ru(II) or Os(II); BL = dpp = 2,3-bis(2-pyridyl)pyrazine, dpq = 2,3-bis(2-pyridyl)quinoxaline, or bpm = 2,2'-bipyrimidine) were synthesized and their redox, spectroscopic, and photophysical properties investigated. The tetrametallic complexes couple a Pt(II)-based reactive metal center to Ru and/or Os light absorbers through two different polyazine BL to provide structural diversity and interesting resultant properties. The redox potential of the M(II/III) couple is modulated by M variation, with the terminal Ru(II/III) occurring at 1.58-1.61 V and terminal Os(II/III) couples at 1.07-1.18 V versus Ag/AgCl. [{(TL)(2)M(dpp)}(2)Ru(BL)](PF(6))(6) display terminal M(dπ)-based highest occupied molecular orbitals (HOMOs) with the dpp(π*)-based lowest unoccupied molecular orbital (LUMO) energy relatively unaffected by the nature of BL. The coupling of Pt to the BL results in orbital inversion with localization of the LUMO on the remote BL in the tetrametallic complexes, providing a lowest energy charge separated (CS) state with an oxidized terminal Ru or Os and spatially separated reduced BL. The complexes [{(TL)(2)M(dpp)}(2)Ru(BL)](6+) and [{(TL)(2)M(dpp)}(2)Ru(BL)PtCl(2)](6+) efficiently absorb light throughout the UV and visible regions with intense metal-to-ligand charge transfer (MLCT) transitions in the visible at about 540 nm (M = Ru) and 560 nm (M = Os) (ε ≈ 33,000-42,000 M(-1) cm(-1)) and direct excitation to the spin-forbidden (3)MLCT excited state in the Os complexes about 720 nm. All the trimetallic and tetrametallic Ru-based supramolecular systems emit from the terminal Ru(dπ)→dpp(π*) (3)MLCT state, λ(max)(em) ≈ 750 nm. The tetrametallic systems display complex excited state dynamics with quenching of the (3)MLCT emission at room temperature to populate the lowest-lying (3)CS state population of the emissive (3)MLCT state.

A nomogram to estimate the HbA1c response to different DPP-4 inhibitors in type 2 diabetes: a systematic review and meta-analysis of 98 trials with 24 163 patients

PubMed Central

Esposito, Katherine; Chiodini, Paolo; Maiorino, Maria Ida; Capuano, Annalisa; Cozzolino, Domenico; Petrizzo, Michela; Bellastella, Giuseppe; Giugliano, Dario

2015-01-01

Objectives To develop a nomogram for estimating the glycated haemoglobin (HbA1c) response to different dipeptidyl peptidase-4 (DPP-4) inhibitors in type 2 diabetes. Design A systematic review and meta-analysis of randomised controlled trials (RCTs) of DPP-4 inhibitors (vildagliptin, sitagliptin, saxagliptin, linagliptin and alogliptin) on HbA1c were conducted. Electronic searches were carried out up to December 2013. Trials were included if they were carried out on participants with type 2 diabetes, lasted at least 12 weeks, included at least 30 participants and had a final assessment of HbA1c. A random effect model was used to pool data. A nomogram was used to represent results of the metaregression model. Participants Adults with type 2 diabetes. Interventions Any DPP-4 inhibitor (vildagliptin, sitagliptin, saxagliptin, linagliptin or alogliptin). Outcome measures The HbA1c response to each DPP-4 inhibitor within 1 year of therapy. Results We screened 928 citations and reviewed 98 articles reporting 98 RCTs with 100 arms in 24 163 participants. There were 26 arms with vildagliptin, 37 with sitagliptin, 13 with saxagliptin, 13 with linagliptin and 11 with alogliptin. For all 100 arms, the mean baseline HbA1c value was 8.05% (64 mmol/mol); the decrease of HbA1c from baseline was −0.77% (95% CI −0.82 to −0.72%), with high heterogeneity (I2=96%). Multivariable metaregression model that included baseline HbA1c, type of DPP-4 inhibitor and fasting glucose explained 58% of variance between studies, with no significant interaction between them. Other factors, including age, previous diabetes drugs and duration of treatment added low predictive power (<1%). The nomogram estimates the absolute HbA1c reduction from baseline using the type of DPP-4 inhibitor, baseline values of HbA1c and fasting glucose. Conclusions Baseline HbA1c level and fasting glucose explain most of the variance in HbA1c change in response to DPP-4 inhibitors: each increase of 1.0% units HbA1c provides a 0.4–0.5% units greater fall. PMID:25687897

Shifting the paradigm in Dirofilaria immitis prevention: blocking transmission from mosquitoes to dogs using repellents/insecticides and macrocyclic lactone prevention as part of a multimodal approach.

PubMed

McCall, John W; Varloud, Marie; Hodgkins, Elizabeth; Mansour, Abdelmoneim; DiCosty, Utami; McCall, Scott; Carmichael, James; Carson, Ben; Carter, Justin

2017-11-09

This study assessed the influence of a topical ectoparasiticide (dinotefuran-permethrin-pyriproxyfen, DPP, Vectra® 3D, Ceva Animal Health) combined with a macrocyclic lactone (milbemycin oxime, MBO, Interceptor®, Virbac) on transmission of heartworm L3 from mosquitoes to dogs and subsequent development of worms in treated dogs exposed to infected mosquitoes. Thirty-two beagle dogs were allocated to four groups of eight: Group 1, untreated controls; Group 2, treated topically with DPP on Day 0; Group 3, treated orally with MBO on Day 51; and Group 4, treated with DPP on Day 0 and MBO on Day 51. Dogs were exposed under sedation for 1 h to Dirofilaria immitis (JYD-34)-infected Aedes aegypti on Days 21 and 28. At the end of each exposure, mosquitoes were classified as live, moribund, or dead and engorged or non-engorged. Live or moribund mosquitoes were incubated for daily survival assessment for 3 days. Mosquitoes were dissected before and after exposure to estimate the number of L3 transmitted to each dog. Dogs were necropsied 148 to 149 days postinfection. A total of 418 mosquitoes fed on the 16 dogs in Groups 1 and 3, while only 6 fed on the 16 DPP-treated dogs in Groups 2 and 4. Mosquito anti-feeding (repellency) effect in Groups 2 and 4 was 98.1 and 99.1%, respectively. The estimated numbers of L3 transmitted to controls, DPP-treated, MBO-treated and DPP + MBO-treated dogs were 76, 2, 78, and 1, respectively. No heartworms were detected in any of the DPP + MBO-treated dogs (100% efficacy), while 8 out of 8 were infected in the control group (range, 21-66 worms per dog), 8 out of 8 were infected in the MBO-treated group (58% efficacy), and 3 out of 8 were infected in the DPP-treated group (96% efficacy). DPP repelled and killed most mosquitoes that were capable of transmitting heartworm L3 to dogs. The "Double Defense" protocol of DPP + MBO had better efficacy for protecting dogs against heartworm transmission and infection than MBO alone. This added DPP benefit is more pronounced when macrocyclic lactone-resistant strains of heartworms are involved or lack of compliance in macrocyclic lactone administration is known or suspected.

The 12-month effects of structured lifestyle advice and pelvic floor muscle training for pelvic organ prolapse.

PubMed

Due, Ulla; Brostrøm, Søren; Lose, Gunnar

2016-07-01

We evaluated the 12-month effects of adding pelvic floor muscle training to a lifestyle advice program in women with symptomatic pelvic organ prolapse stage II-III and the number of women who had sought further treatment. This study was a 12-month follow up of a randomized controlled trial comparing a structured lifestyle advice program alone (lifestyle group) or in combination with pelvic floor muscle training (training and lifestyle group). Both programs consisted of six separate group sessions within 12 weeks. Data were available from 83 (76%) of the 109 originally included women. At the 12-month follow up, 34/83 (41%) had not sought further treatment, 13/43 (30%) in the lifestyle group and 21/40 (52%) in the training and lifestyle group, and these could be included for analysis. The lifestyle group had significantly improved bladder symptoms compared with baseline on single-item analysis (p = 0.01). The training and lifestyle group had significantly improved pelvic organ prolapse symptoms on single-item analysis (p = 0.02) and of bowel-related quality of life (p = 0.04). No significant between-group differences were found in the symptom and quality of life scores. All together 49 women (59%) had sought further treatment, 70% in the lifestyle group, and 48% in the training and lifestyle group (p = 0.05). Twenty-six in the lifestyle group, and 15 in the training and lifestyle group had sought conservative treatment. Four women in each group had received surgery. More severe anterior prolapse and more bladder symptoms at the 3-month follow up were significantly associated with having sought further treatment in both groups. At 12-month follow up, the effects of adding pelvic floor muscle training to a structured lifestyle advice program were limited. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

An after-school dance and lifestyle education program reduces risk factors for heart disease and diabetes in elementary school children

PubMed Central

Hogg, Jeannette; Diaz, Alejandro; Cid, Margareth Del; Mueller, Charles; Lipman, Elizabeth Grace; Cheruvu, Sunita; Chiu, Ya-lin; Vogiatzi, Maria; Nimkarn, Saroj

2013-01-01

Background Forty-three percent of New York City's (NYC) school-age children are overweight or obese, placing them at risk for heart disease and type 2 diabetes mellitus (T2DM). Objective The objective of this study was to determine if an intensive after-school dance and lifestyle education program would reduce risk factors for heart disease, T2DM, and improve lifestyle choices. Subjects Subject include 64 fourth- and fifth-grade students at an elementary school in NYC. Methods Students received freestyle dance and lifestyle classes for 16 weeks and were evaluated for changes in body composition, endurance, biochemical measurements, and lifestyle choices. Results Significant improvements in BMI percentiles were found among children in the overweight and obese categories as well as in endurance and biochemical measurements that reflect heart disease and diabetes risk. Improvement was also reported in lifestyle choices. Conclusion An intensive after-school dance and lifestyle education program can reduce risk factors for heart disease and T2DM and improve lifestyle choices among elementary school children. PMID:22876547

H. pylori seroprevalence and risk of diabetes: An ancillary case-control study nested in the diabetes prevention program.

PubMed

Alzahrani, Saud; Nelson, Jason; Moss, Steven F; Paulus, Jessica K; Knowler, William C; Pittas, Anastassios G

2017-10-01

To determine the association between H. pylori infection and risk of incident diabetes in adults at high risk for diabetes who participated in the Diabetes Prevention Program (DPP) study. In a nested case-control study conducted among 421 adults with newly diagnosed diabetes and 421 matched controls, we examined the association between serological status of H. pylori at baseline and risk of incident diabetes over a mean follow-up period of 2.6years. Using data from the baseline visit of the DPP, we also examined the cross-sectional association between presence of H. pylori antibodies and insulin sensitivity, insulin secretion and the disposition index-like measure after a 75-g oral glucose tolerance test (OGTT). At baseline, H. pylori antibodies were present in 40% of participants who developed diabetes and 39% of controls. After adjusting for matching factors, there was no association between exposure to H. pylori and incident diabetes (odds ratio [OR] of 1.04 (95% CI, 0.77 to 1.40). In cross-sectional analyses, H. pylori status was not significantly associated with insulin sensitivity and disposition index-like measure from OGTT. In adults at high risk for diabetes, H. pylori seropositivity was not associated with risk of developing diabetes. Copyright © 2017 Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagamatsu, Shinya, E-mail: shinya@ks.kyorin-u.ac.jp; Ohara-Imaizumi, Mica; Nakamichi, Yoko

Highlights: {yields} Anti-diabetic new drug, DPP-4 inhibitor, can affect the insulin exocytosis. {yields} DPP-4 inhibitor treatment altered syntaxin 1 expression. {yields} Treatment of db/db mice with DPP-4 inhibitor increased insulin release. -- Abstract: Incretin promotes insulin secretion acutely. Recently, orally-administered DPP-4 inhibitors represent a new class of anti-hyperglycemic agents. Indeed, inhibitors of dipeptidyl peptidase-IV (DPP-4), sitagliptin, has just begun to be widely used as therapeutics for type 2 diabetes. However, the effects of sitagliptin-treatment on insulin exocytosis from single {beta}-cells are yet unknown. We therefore investigated how sitagliptin-treatment in db/db mice affects insulin exocytosis by treating db/db mice with des-F-sitagliptinmore » for 2 weeks. Perfusion studies showed that 2 weeks-sitagliptin treatment potentiated insulin secretion. We then analyzed insulin granule motion and SNARE protein, syntaxin 1, by TIRF imaging system. TIRF imaging of insulin exocytosis showed the increased number of docked insulin granules and increased fusion events from them during first-phase release. In accord with insulin exocytosis data, des-F-sitagliptin-treatment increased the number of syntaxin 1 clusters on the plasma membrane. Thus, our data demonstrated that 2-weeks des-F-sitagliptin-treatment increased the fusion events of insulin granules, probably via increased number of docked insulin granules and that of syntaxin 1 clusters.« less

Ectopic expression of dentin sialoprotein during amelogenesis hardens bulk enamel.

PubMed

White, Shane N; Paine, Michael L; Ngan, Amanda Y W; Miklus, Vetea G; Luo, Wen; Wang, HongJun; Snead, Malcolm L

2007-02-23

Dentin sialophosphpoprotein (Dspp) is transiently expressed in the early stage of secretory ameloblasts. The secretion of ameloblast-derived Dspp is short-lived, correlates to the establishment of the dentinoenamel junction (DEJ), and is consistent with Dspp having a role in producing the specialized first-formed harder enamel adjacent to the DEJ. Crack diffusion by branching and dissipation within this specialized first-formed enamel close to the DEJ prevents catastrophic interfacial damage and tooth failure. Once Dspp is secreted, it is subjected to proteolytic cleavage that results in two distinct proteins referred to as dentin sialoprotein (Dsp) and dentin phosphoprotein (Dpp). The purpose of this study was to investigate the biological and mechanical contribution of Dsp and Dpp to enamel formation. Transgenic mice were engineered to overexpress either Dsp or Dpp in their enamel organs. The mechanical properties (hardness and toughness) of the mature enamel of transgenic mice were compared with genetically matched and age-matched nontransgenic animals. Dsp and Dpp contributions to enamel formation greatly differed. The inclusion of Dsp in bulk enamel significantly and uniformly increased enamel hardness (20%), whereas the inclusion of Dpp weakened the bulk enamel. Thus, Dsp appears to make a unique contribution to the physical properties of the DEJ. Dsp transgenic animals have been engineered with superior enamel mechanical properties.

Hypoglycemia hospitalization frequency in patients with type 2 diabetes mellitus: a comparison of dipeptidyl peptidase 4 inhibitors and insulin secretagogues using the French health insurance database.

PubMed

Detournay, Bruno; Halimi, Serge; Robert, Julien; Deschaseaux, Céline; Dejager, Sylvie

2015-01-01

We aimed to compare the frequency of severe hypoglycemia leading to hospitalization (HH) and emergency visits (EV) for any cause in patients with type 2 diabetes mellitus exposed to dipeptidyl peptidase 4 (DPP4) inhibitors (DPP4-i) versus those exposed to insulin secretagogues (IS; sulfonylureas or glinides). Data were extracted from the EGB (Echantillon Généraliste des Bénéficiaires) database, comprising a representative sample of ~1% of patients registered in the French National Health Insurance System (~600,000 patients). Type 2 diabetes mellitus patients exposed to regimens containing either a DPP4-i (excluding treatment with IS, insulin, or glucagon-like peptide 1 analog) or IS (excluding treatment with insulin and any incretin therapy) between 2009 and 2012 were selected. HH and EV during the exposure periods were identified in both cohorts. A similar analysis was conducted considering vildagliptin alone versus IS. Comparative analyses adjusting for covariates within the model (subjects matched for key characteristics) and using multinomial regression models were performed. Overall, 7,152 patients exposed to any DPP4-i and 1,440 patients exposed to vildagliptin were compared to 10,019 patients exposed to IS. Eight patients (0.11%) from the DPP4-i cohort and none from the vildagliptin cohort (0.0%) were hospitalized for hypoglycemia versus 130 patients (1.30%) from the IS cohort (138 hospitalizations) (P=0.02 and P<0.0001, respectively). Crude rates of HH/1,000 patient-years were 1.4 (95% CI: 0.7; 2.4) in the DPP4-i cohort, 0.0 in the vildagliptin cohort (95% CI: 0.0; 4.0), versus 5.6 (95% CI, 4.7; 6.6) in the IS cohort (P<0.0001). After adjustments, rates per 1,000 patient-years of HH were 1.4 (95% CI: 0.7; 2.4) with DPP4-i versus 7.5 (95% CI: 6.0; 9.2) with IS (P<0.0001), and 0.0 (95% CI: 0.0; 4.0) with vildagliptin versus 13.6 (95% CI: 10.4; 17.5) with IS (P<0.0001). Adjusted EV rates were also significantly lower with all DPP4-i or with vildagliptin, as compared to IS (P<0.0001). Consistent results were found when considering only treatment initiations for all compared cohorts. HH and EV were significantly less frequent in patients exposed to any DPP4-i or to vildagliptin versus IS. These real-life data should be considered in the benefit/risk evaluation of the drugs.

Hypoglycemia hospitalization frequency in patients with type 2 diabetes mellitus: a comparison of dipeptidyl peptidase 4 inhibitors and insulin secretagogues using the French health insurance database

PubMed Central

Detournay, Bruno; Halimi, Serge; Robert, Julien; Deschaseaux, Céline; Dejager, Sylvie

2015-01-01

Aim We aimed to compare the frequency of severe hypoglycemia leading to hospitalization (HH) and emergency visits (EV) for any cause in patients with type 2 diabetes mellitus exposed to dipeptidyl peptidase 4 (DPP4) inhibitors (DPP4-i) versus those exposed to insulin secretagogues (IS; sulfonylureas or glinides). Methods Data were extracted from the EGB (Echantillon Généraliste des Bénéficiaires) database, comprising a representative sample of ~1% of patients registered in the French National Health Insurance System (~600,000 patients). Type 2 diabetes mellitus patients exposed to regimens containing either a DPP4-i (excluding treatment with IS, insulin, or glucagon-like peptide 1 analog) or IS (excluding treatment with insulin and any incretin therapy) between 2009 and 2012 were selected. HH and EV during the exposure periods were identified in both cohorts. A similar analysis was conducted considering vildagliptin alone versus IS. Comparative analyses adjusting for covariates within the model (subjects matched for key characteristics) and using multinomial regression models were performed. Results Overall, 7,152 patients exposed to any DPP4-i and 1,440 patients exposed to vildagliptin were compared to 10,019 patients exposed to IS. Eight patients (0.11%) from the DPP4-i cohort and none from the vildagliptin cohort (0.0%) were hospitalized for hypoglycemia versus 130 patients (1.30%) from the IS cohort (138 hospitalizations) (P=0.02 and P<0.0001, respectively). Crude rates of HH/1,000 patient-years were 1.4 (95% CI: 0.7; 2.4) in the DPP4-i cohort, 0.0 in the vildagliptin cohort (95% CI: 0.0; 4.0), versus 5.6 (95% CI, 4.7; 6.6) in the IS cohort (P<0.0001). After adjustments, rates per 1,000 patient-years of HH were 1.4 (95% CI: 0.7; 2.4) with DPP4-i versus 7.5 (95% CI: 6.0; 9.2) with IS (P<0.0001), and 0.0 (95% CI: 0.0; 4.0) with vildagliptin versus 13.6 (95% CI: 10.4; 17.5) with IS (P<0.0001). Adjusted EV rates were also significantly lower with all DPP4-i or with vildagliptin, as compared to IS (P<0.0001). Consistent results were found when considering only treatment initiations for all compared cohorts. Conclusion HH and EV were significantly less frequent in patients exposed to any DPP4-i or to vildagliptin versus IS. These real-life data should be considered in the benefit/risk evaluation of the drugs. PMID:26229480

Chromogenic Detection of Dipeptidyl Peptidase IV (DPP-IV) Activity using Peptide-Functionalized Gold Nanoparticles

NASA Astrophysics Data System (ADS)

Abul-Huda, Yasin Mohammad

Metal nanoparticles offer a useful platform for a wide range of biological applications especially for biosensing, bioimaging and drug delivery. This thesis presents a body of original research describing the synthesis, characterisation and development of a novel and convenient biosensing assay for detection of dipeptidyl peptidase IV (DPP-IV) enzyme activity using peptide functionalized gold nanoparticles. The distinctive optical and physical properties of gold nanoparticles (Au NP) were harnessed for the development of a colorimetric assay for rapid sensing of DPP-IV activities and screening DPP-IV inhbitors. The citrate reduction method for Au NPs synthesis was optimised and several potential peptide substrates (GPDC, VP-EN-DC, C/G dipeptide, GPG-EN-PEG4-LA, GPDCALNNC) were designed to provide substrates that mimic the DPP-IV natural substrates. The performances of the substrate functionalized Au NPs were assessed for their appropriateness for the detection of the enzyme activity. Addition of DPP-IV to the solutions containing the functionalized Au NPs resulted in cleavage of the substrate and thus causing the aggregation of the Au NPs which in turn led to a shift of the surface plasmon peak toward longer wavelengths, and a change of the colour of the colloidal suspension from red to blue. Overall, real-time detection of DPP-IV activity over a broader range (0-40 U/L) with high selectivity and stability was obtained, thus providing a method that can be used to determine the levels of DPP-IV/CD26 in biological fluids such as serum and plasma. Further assay developments were conducted to overcome limitations encountered with the original Au NP assay, especially the narrow dynamic linear range and stability in high ionic strength solutions. Validation and comparison of the Au NP assay developed has revealed that this method is highly correlated to the gold standard chromogenic Gly-Pro-pNA method for detection of enzyme activity in biological samples. Very good recoveries (in the range 83.6 -114.9%) were obtained in spiked serum samples, which indicate that this assay could provide a suitable alternative for enzyme activity detection with the naked eye and without the need for sophisticated instruments. Investigations into the effects of incorporating different stabilizers in order to improve the stability of the peptide functionalized Au NP in high ionic strength solutions were also investigated. Gold nanoparticles have different shapes and structures and an alternative approach for detection of DPP-IV activity using gold nanorods due to their higher refractive index sensitivities was explored. As a conclusion, three out of five approaches, all utilising Au NP-ligand conjugates were demonstrated useful for the detection of the DPP-IV activity. The system developed here is portable and would permit on-site analysis of samples, which offers a real alternative approach from traditional assays and reduces the need for laboratory testing. The logical next step in this research would be the continuation of experiments to transform this test into a point of care testing device that could offer an early detection tool for disease management.

Supporting adherence and healthy lifestyles in leg ulcer patients: systematic development of the Lively Legs program for dermatology outpatient clinics.

PubMed

Heinen, Maud M; Bartholomew, L Kay; Wensing, Michel; van de Kerkhof, Peter; van Achterberg, Theo

2006-05-01

The objective of our project was to develop a lifestyle program for leg ulcer patients at outpatient clinics for dermatology. We used the intervention-mapping (IM) framework for systematically developing theory and evidence based health promotion programs. We started with a needs-assessment. A multidisciplinary project group of health care workers and patients was involved in all five IM steps; formulating proximal program objectives, selecting methods and strategies, producing program components, planning for adoption and implementation and planning for evaluation. Several systematic literature reviews and original studies were performed to support this process. Social Cognitive Theory was selected as the main theory behind the program 'Lively Legs' and was combined with elements of Goal-Setting Theory, the precaution adoption model and motivational interviewing. The program is conducted through health counseling by dermatology nurses and was successfully pre-tested. Also, an implementation and evaluation plan were made. Intervention mapping helped us to succeed in developing a lifestyle program with clear goals and methods, operational strategies and materials and clear procedures. Coaching leg ulcer patients towards adherence with compression therapy and healthy lifestyles should be taken on without delay. Systematic development of lifestyle programs for other patient groups should be encouraged.

Clinical Pharmacokinetics and Pharmacodynamics of Saxagliptin, a Dipeptidyl Peptidase-4 Inhibitor.

PubMed

Boulton, David W

2017-01-01

Saxagliptin is an orally active, highly potent, selective and competitive dipeptidyl peptidase (DPP)-4 inhibitor used in the treatment of type 2 diabetes mellitus at doses of 2.5 or 5 mg once daily. DPP-4 is responsible for degrading the intestinally derived hormones glucagon-like peptide (GLP)-1 and glucose-dependent insulinotropic polypeptide (GIP). Inhibition of DPP-4 increases intact plasma GLP-1 and GIP concentrations, augmenting glucose-dependent insulin secretion. Both saxagliptin and its major active metabolite, 5-hydroxy saxagliptin, demonstrate high degrees of selectivity for DPP-4 compared with other DPP enzymes. Saxagliptin is orally absorbed and can be administered with or without food. The half-life of plasma DPP-4 inhibition with saxagliptin 5 mg is ~27 h, which supports a once-daily dosing regimen. Saxagliptin is metabolized by cytochrome P450 (CYP) 3A4/5 and is eliminated by a combination of renal and hepatic clearance. No clinically meaningful differences in saxagliptin or 5-hydroxy saxagliptin pharmacokinetics have been detected in patients with hepatic impairment. No clinically meaningful differences in saxagliptin or 5-hydroxy saxagliptin pharmacokinetics have been detected in patients with mild renal impairment, whereas dose reduction is recommended in patients with moderate or severe renal impairment because of greater systemic exposure [the area under the plasma concentration-time curve (AUC)] to saxagliptin total active moieties. Clinically relevant drug-drug interactions have not been detected; however, limiting the dose to 2.5 mg once daily is recommended in the USA when saxagliptin is coadministered with strong CYP inhibitors, because of increased saxagliptin exposure. In summary, saxagliptin has a predictable pharmacokinetic and pharmacodynamic profile.

DPP IV inhibitor treatment attenuates bone loss and improves mechanical bone strength in male diabetic rats.

PubMed

Glorie, Lorenzo; Behets, Geert J; Baerts, Lesley; De Meester, Ingrid; D'Haese, Patrick C; Verhulst, Anja

2014-09-01

Dipeptidyl peptidase IV (DPP IV) modulates protein activity by removing dipeptides. DPP IV inhibitors are currently used to improve glucose tolerance in type 2 diabetes patients. DPP IV substrates not only increase insulin secretion but also affect bone metabolism. In this study, the effect of DPP IV inhibitor sitagliptin on bone was evaluated in normal and streptozotocin-induced diabetic rats. This study included 64 male Wistar rats divided into four groups (n = 16): two diabetic and two control groups. One diabetic and one control group received sitagliptin through drinking water. Tibiae were scanned every 3 wk using an in vivo μCT scanner. After 6 and 12 wk, rats were euthanized for histomorphometric analysis of bone parameters. The mechanical resistance of femora to fracture was assessed using a three-point bending test, and serum levels of bone metabolic markers were measured. Efficient DPP IV inhibition was achieved in sitagliptin-treated groups. Trabecular bone loss, the decrease in trabecular number, and the increase in trabecular spacing was attenuated through sitagliptin treatment in diabetic rats, as shown by in vivo μCT. Bone histomorphometry was in line with these results. μCT analysis furthermore showed that sitagliptin prevented cortical bone growth stagnation in diabetic rats, resulting in stronger femora during three-point bending. Finally, the serum levels of the resorption marker CTX-I were significantly lower in sitagliptin-treated diabetic animals compared with untreated diabetic animals. In conclusion, sitagliptin treatment attenuates bone loss and increases bone strength in diabetic rats probably through the reduction of bone resorption and independent of glycemic management. Copyright © 2014 the American Physiological Society.

Dipeptidyl-peptidase IV (DPP-IV) inhibitor delays tolerance to anxiolytic effect of ethanol and withdrawal-induced anxiety in rats.

PubMed

Sharma, Ajaykumar N; Pise, Ashish; Sharma, Jay N; Shukla, Praveen

2015-06-01

Dipeptidyl-peptidase IV (DPP-IV) is an enzyme responsible for the metabolism of endogenous gut-derived hormone, glucagon-like peptide-1 (GLP-1). DPP-IV is known for its role in energy homeostasis and pharmacological blockade of this enzyme is a recently approved clinical strategy for the management of type II diabetes. Accumulating evidences suggest that enzyme DPP-IV can affect spectrum of central nervous system (CNS) functions. However, little is known about the role of this enzyme in ethanol-mediated neurobehavioral complications. The objective of the present study was to examine the impact of DPP-IV inhibitor, sitagliptin on the development of tolerance to anxiolytic effect of ethanol and anxiety associated with ethanol withdrawal in rats. A dose-response study revealed that sitaglitpin (20 mg/kg, p.o.) per se exhibit anxiolytic effect in the elevated plus maze (EPM) test in rats. Tolerance to anxiolytic effect of ethanol (2 g/kg, i.p.; 8 % w/v) was observed from 7(th) day of ethanol-diet (6 % v/v) consumption. In contrast, tolerance to anxiolytic effect of ethanol was delayed in rats that were treated daily with sitagliptin (20 mg/kg, p.o.) as tolerance was observed from 13(th)day since commencement of ethanol-diet consumption. Discontinuation of rats from ethanol-diet after 15-days of ethanol consumption resulted in withdrawal anxiety between 8 h and 12 h post-abstinence. However, rats on 15-day ethanol-diet with concomitant sitagliptin (20 mg/kg, p.o.) treatment exhibited delay in appearance (24 h post-withdrawal) of withdrawal anxiety. In summary, DPP-IV inhibitors may prove as an attractive research strategy against ethanol tolerance and dependence.

Maternal deprivation decelerates postnatal morphological lung development of F344 rats.

PubMed

Hupa, Katharina Luise; Schmiedl, Andreas; Pabst, Reinhard; Von Hörsten, Stephan; Stephan, Michael

2014-02-01

Intensive medical care at premature born infants is often associated with separation of neonates from their mothers. Here, early artificial prolonged separation of rat pups from their dams (Maternal Deprivation, MD) was used to study potential impact on morphological lung maturation. Furthermore, we investigated the influence of an endogenous deficiency of the neuropeptide-cleaving dipeptidyl peptidase IV (DPP4), since the effects of MD are known to be partly mediated via neuropeptidergic effects, hypothesizing that MD will lead to a retardation of postnatal lung development, DPP4-dependendly. We used wild type and CD26/DPP4 deficient rats. For MD, the dam was placed each day into a separate cage for 2 h, while the pups remained in the nest on their own. Morphological lung maturation and cell proliferation at the postnatal days 7, 10, 14, and 21 were determined morphometrically. Maternally deprived wild types showed a retarded postnatal lung development compared with untreated controls in both substrains. During alveolarization, an increased thickness of alveolar septa and a decreased surface of septa about 50% were found. At the end of the morphological lung maturation, the surface of the alveolar septa was decreased at about 25% and the septal thickness remained increased about 20%. The proliferation rate was also decreased about 50% on day 14. However, the MD induced effects were less pronounced in DPP4-deficient rats, due to a significant deceleration already induced by DPP4-deficiency. Thus, MD as a model for postnatal stress experience influences remarkably postnatal development of rats, which is significantly modulated by the DPP4-system. Copyright © 2013 Wiley Periodicals, Inc.

Mouse-adapted MERS coronavirus causes lethal lung disease in human DPP4 knockin mice.

PubMed

Li, Kun; Wohlford-Lenane, Christine L; Channappanavar, Rudragouda; Park, Jung-Eun; Earnest, James T; Bair, Thomas B; Bates, Amber M; Brogden, Kim A; Flaherty, Heather A; Gallagher, Tom; Meyerholz, David K; Perlman, Stanley; McCray, Paul B

2017-04-11

The Middle East respiratory syndrome (MERS) emerged in Saudi Arabia in 2012, caused by a zoonotically transmitted coronavirus (CoV). Over 1,900 cases have been reported to date, with ∼36% fatality rate. Lack of autopsies from MERS cases has hindered understanding of MERS-CoV pathogenesis. A small animal model that develops progressive pulmonary manifestations when infected with MERS-CoV would advance the field. As mice are restricted to infection at the level of DPP4, the MERS-CoV receptor, we generated mice with humanized exons 10-12 of the mouse Dpp4 locus. Upon inoculation with MERS-CoV, human DPP4 knockin (KI) mice supported virus replication in the lungs, but developed no illness. After 30 serial passages through the lungs of KI mice, a mouse-adapted virus emerged (MERS MA ) that grew in lungs to over 100 times higher titers than the starting virus. A plaque-purified MERS MA clone caused weight loss and fatal infection. Virus antigen was observed in airway epithelia, pneumocytes, and macrophages. Pathologic findings included diffuse alveolar damage with pulmonary edema and hyaline membrane formation associated with accumulation of activated inflammatory monocyte-macrophages and neutrophils in the lungs. Relative to the parental MERS-CoV, MERS MA viruses contained 13-22 mutations, including several within the spike (S) glycoprotein gene. S-protein mutations sensitized viruses to entry-activating serine proteases and conferred more rapid entry kinetics. Recombinant MERS MA bearing mutant S proteins were more virulent than the parental virus in hDPP4 KI mice. The hDPP4 KI mouse and the MERS MA provide tools to investigate disease causes and develop new therapies.

Sitagliptin, a dipeptidyl peptidase-4 inhibitor, improves recognition memory, oxidative stress and hippocampal neurogenesis and upregulates key genes involved in cognitive decline.

PubMed

Gault, V A; Lennox, R; Flatt, P R

2015-04-01

To examine whether prolonged dipeptidyl peptidase-4 (DPP-4) inhibition can reverse learning and memory impairment in high-fat-fed mice. High-fat-fed mice received oral sitagliptin (50 mg/kg body weight) once daily or saline vehicle over 21 days. An additional group of mice on standard chow received saline vehicle. Energy intake, body weight, glucose and insulin concentrations were measured at regular intervals. Glucose tolerance, insulin sensitivity, novel object recognition, DPP-4 activity, hormone analysis, hippocampal gene expression and histology were performed. Sitagliptin decreased circulating DPP-4 activity and improved glucose tolerance, glucose-stimulated insulin secretion and insulin sensitivity, and reduced plasma triglycerides and cholesterol levels. DPP-4 inhibition improved recognition memory (1.2-fold increase) without affecting hypermoteric activity or anxiety levels. Improvement in memory and learning was linked to reduced immunostaining for 8-oxoguanine and increased doublecortin staining in the hippocampus, which were indicative of reduced brain oxidative stress and increased hippocampal neurogenesis, respectively. These effects were associated with significant upregulation of hippocampal gene expression of glucagon-like peptide-1 (GLP-1) receptor, glucose-dependent insulinotropic polypeptide receptor, synaptophysin, sirtuin 1, glycogen synthase kinase 3β, superdioxide mutase 2, nuclear factor (erythroid-derived 2)-like 2 and vascular endothelial growth factor. Total plasma and brain GLP-1 concentrations were significantly increased after sitagliptin therapy, whereas DPP-4 activity in brain tissue was not altered. These studies show that sitagliptin can reverse memory impairment in high-fat-fed mice and is also associated with improved insulin sensitivity, enhanced hippocampal neurogenesis and reduced oxidative stress. DPP-4 inhibitors may therefore exhibit dual benefits by improving metabolic control and reducing the decline in cognitive function. © 2015 John Wiley & Sons Ltd.

Hibiscus sabdariffa polyphenols prevent palmitate-induced renal epithelial mesenchymal transition by alleviating dipeptidyl peptidase-4-mediated insulin resistance.

PubMed

Huang, Chien-Ning; Wang, Chau-Jong; Yang, Yi-Sun; Lin, Chih-Li; Peng, Chiung-Huei

2016-01-01

Diabetic nephropathy has a significant socioeconomic impact, but its mechanism is unclear and needs to be examined. Hibiscus sabdariffa polyphenols (HPE) inhibited high glucose-induced angiotensin II receptor-1 (AT-1), thus attenuating renal epithelial mesenchymal transition (EMT). Recently, we reported HPE inhibited dipeptidyl-peptidase-4 (DPP-4, the enzyme degrades type 1 glucagon-like peptide (GLP-1)), which mediated insulin resistance signals leading to EMT. Since free fatty acids can realistically bring about insulin resistance, using the palmitate-stimulated cell model in contrast with type 2 diabetic rats, in this study we examined if insulin resistance causes renal EMT, and the preventive effect of HPE. Our findings reveal that palmitate hindered 30% of glucose uptake. Treatment with 1 mg mL(-1) of HPE and the DPP-4 inhibitor linagliptin completely recovered insulin sensitivity and palmitate-induced signal cascades. HPE inhibited DPP-4 activity without altering the levels of DPP-4 and the GLP-1 receptor (GLP-1R). HPE decreased palmitate-induced phosphorylation of Ser307 of insulin receptor substrate-1 (pIRS-1 (S307)), AT-1 and vimentin, while increasing phosphorylation of phosphatidylinositol 3-kinase (pPI3K). IRS-1 knockdown revealed its essential role in mediating downstream AT-1 and EMT. In type 2 diabetic rats, it suggests that HPE concomitantly decreased the protein levels of DPP-4, AT-1, vimentin, and fibronectin, but reversed the in vivo compensation of GLP-1R. In conclusion, HPE improves insulin sensitivity by attenuating DPP-4 and the downstream signals, thus decreasing AT-1-mediated tubular-interstitial EMT. HPE could be an adjuvant to prevent diabetic nephropathy.

Anti-inflammatory and antiproliferative activities of date palm pollen (Phoenix dactylifera) on experimentally-induced atypical prostatic hyperplasia in rats

PubMed Central

2011-01-01

Background Atypical prostatic hyperplasia (APH) is a pseudoneoplastic lesion that can mimic prostate adenocarcinoma because of its cytologic and architectural features. Suspension of date palm pollen (DPP) is an herbal mixture that is widely used in folk medicine for male infertility. The aim of the present study was to evaluate the effect of DPP suspension and extract on APH-induced rats. Methods APH was induced in adult castrated Wistar rats by both s.c. injection of testosterone (0.5 mg/rat/day) and smearing citral on shaved skin once every 3 days for 30 days. Saw palmetto (100mg/kg), DPP suspension (250, 500 and 1000 mg/kg), and lyophilized DPP extract (150,300 and 600 mg/kg) were given orally daily for 30 days. All medications were started 7 days after castration and along with testosterone and citral. Results The histopathological feature in APH-induced prostate rats showed evidence of hyperplasia and inflammation. Immunohistochemical examination revealed that the expressions of IL-6, IL-8, TNF-α, IGF-1 and clusterin were increased, while the expression of TGF-β1 was decreased that correlates with presence of inflammation. Moreover, histopathological examination revealed increased cellular proliferation and reduced apoptosis in ventral prostate. Both saw palmetto and DPP treatment has ameliorated these histopathological and immunohistochemical changes in APH-induced rats. These improvements were not associated with reduction in the prostatic weight that may be attributed to the persistence of edema. Conclusion DPP may have a potential protective effect in APH-induced Wistar rats through modulation of cytokine expression and/or upregulation of their autocrine/paracrine receptors. PMID:22195697

[Combination therapy of metformin vs dipeptidulpeptidase inhibitors and sulfonylureas in type 2 diabetes: clinical and economic impact].

PubMed

Sicras-Mainar, Antoni; Navarro-Artieda, Ruth

2014-01-01

Determine the clinical repurcussions of adherence, metabolic control, hypoglycemia and cardiovascular events (CVE) and economics (resources and costs) in the combination therapy of metformin vs DPP-4 (dipeptidyl peptidase-4) inhibitors and sulfonylureas in patients with type 2 diabetes. Materials and methods. Observational-multicenter and retrospective design. We evaluated patients ≥ 30 years of age in treatment with metformin and who started a second oral antidiabetic treatment during 2008-2009. 2 study groups were established: a) metformin + DPP-4 inhibitors, and b) metformin + sulfonylurea. comorbidity, metabolic control (HbA1c <7%), compliance and complications (hypoglycemia, CVE). Follow up was conducted over two years. The cost model differentiated between direct healthcare costs (primary/ specialty care), and indirect costs (labor productivity). logistic regression and ANCOVA models. Results. 1,405 patients were recruited (average age 67.1 years old; 56.2% male). 37.0% started a second treatment with DPP-4 inhibitors, and 63.0% with sulfonylureas. After two years of follow up, patients treated with DPP-4 inhibitors showed greater treatment adherence (70.3% vs. 60.6%; p <0.001); better metabolic control (64.3% vs. 60.6%; p<0.001), and a lower proportion of hypoglycemia (13.9% vs. 40.4%; p <0.001, respectively). The average/unit of adjusted total costs was € 2,341 vs. € 2,512; p = 0.038. CVE and renal failure rates were 3.7% vs. 6.4%; p = 0.027. Vildagliptin was the most used drug among DPP-4 inhibitors. Conclusions. Sulfonylureas were the most used drug for diabetes treatment. Patients treated with DPP-4 inhibitors had higher adherence and control of diabetes, with lower rates of hypoglycemia and CVE, resulting in lower healthcare costs.

One-month comparative efficacy of three topical ectoparasiticides against adult brown dog ticks (Rhipicephalus sanguineus sensu lato) on mixed-bred dogs in controlled environment.

PubMed

Varloud, Marie; Fourie, Josephus J

2015-05-01

This study was designed to compare the therapeutic and residual efficacy for 1 month of three topical ectoparasiticides on mixed-bred dogs against the brown dog tick, Rhipicephalus sanguineus. Adult dogs (n = 32, 10.8-18.4 kg BW) were allocated to 4 groups (n = 8) and infested with 50 adult ticks on days -8, -2, 7, 14, 21, and 28. Within each group, dogs were treated topically on day 0 with a control solution (CS), Vectra 3D (DPP), Frontline Plus (FM), or K9 Advantix (IP). Ticks were enumerated on dogs 24 h after treatment and each subsequent tick infestation by in situ thumb count assessment without removal and at 48 h by combing and removal. Acaricidal efficacy was calculated using arithmetic means for all 24 and 48 h tick count assessments. From 42 to 56% of the total, infested ticks were found on dogs 48 h post-challenge in the CS group. Therapeutic efficacy for all treatments ranged from 45.5 to 64.6% after 48 h of infestation. Residual efficacy after FM treatment was consistently lower compared to DPP or IP treatments at the 24 h assessments on days 8, 22, 23, and 29. Residual efficacy measured at this last time point was 94.8% for DPP, 83.1% for IP, and 46.9% for FM. This study demonstrates that permethrin-based formulations (DPP and IP) provided a quicker onset of residual protection against brown dog ticks compared to FM. Although DPP and IP are both permethrin-based formulations, DPP exhibited consistently higher residual acaricidal efficacies and was the only treatment that provided >90% protection for 1 month at 24 h post challenge.

30 CFR 550.270 - What decisions will BOEM make on the DPP or DOCD and within what timeframe?

Code of Federal Regulations, 2013 CFR

2013-07-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Review and Decision Process for the Dpp Or Docd § 550.270 What decisions...

30 CFR 550.270 - What decisions will BOEM make on the DPP or DOCD and within what timeframe?

Code of Federal Regulations, 2012 CFR

2012-07-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Review and Decision Process for the Dpp Or Docd § 550.270 What decisions...

Characterization and identification of novel antidiabetic and anti-obesity peptides from camel milk protein hydrolysates.

PubMed

Mudgil, Priti; Kamal, Hina; Yuen, Gan Chee; Maqsood, Sajid

2018-09-01

In-vitro inhibitory properties of peptides released from camel milk proteins against dipeptidyl peptidase-IV (DPP-IV), porcine pancreatic α-amylase (PPA), and porcine pancreatic lipase (PPL) were studied. Results revealed that upon hydrolysis by different enzymes, camel milk proteins displayed dramatic increase in inhibition of DPP-IV and PPL, but slight improvement in PPA inhibition was noticed. Peptide sequencing revealed a total of 20 and 3 peptides for A9 and B9 hydrolysates respectively, obtained the score of 0.8 or more on peptide ranker and were categorized as potential DPP-IV inhibitory peptides. KDLWDDFKGL in A9 and MPSKPPLL in B9 were identified as most potent PPA inhibitory peptide. For PPL inhibition only 7 and 2 peptides qualified as PPL inhibitory peptides from hydrolysates A9 and B9, respectively. The present study report for the first time PPA and PPL inhibitory and only second for DPP-IV inhibitory potential of protein hydrolysates from camel milk. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluation of optical excitation conditions for ruthenium complex for biosensor optodes

NASA Astrophysics Data System (ADS)

Pieper, Sean; Zhong, Zhong; Lear, Kevin L.; Reardon, Ken

2007-03-01

Development of a fiber optic biosensor incorporating genetically engineered enzymes which catalyze chlorinated ethenes in an oxygen-consuming reaction for in situ monitoring of groundwater contaminants motivates optimization of optode excitation conditions. These conditions affect the sensitivity, signal-to-noise, and optode service life impacting the quality of the overall biosensor. Optodes are generally comprised of a fluorophore conjugated with a polymer as a substrate cross linked at the distal end of a fiber optic. We investigate the excitation conditions of tris(4,7-diphenyl-1,10-phenanthroline) ruthenium(II) chloride (Ru(dpp)3) conjugated with poly(vinyl alcohol) (PVOH) as an optode. A reported advantage of Ru(dpp)3 is that it has no emission spectral shift occurring under varying chemical and environmental conditions. Photostability degradation due to photobleaching of Ru(dpp)3 with PVOH as a substrate is explored by varying the optical irradiance of the fluorophore containing optode. Other issues relating to practical implementation of Ru(dpp)3 as oxygen sensitive biosensors will be discussed.

Evidence for an interaction between leptin, T cell costimulatory antigens CD28, CTLA-4 and CD26 (dipeptidyl peptidase IV) in BCG-induced immune responses of leptin- and leptin receptor-deficient mice.

PubMed

Rüter, Jens; Hoffmann, Torsten; Demuth, Hans-Ulrich; Moschansky, Petra; Klapp, Burghard F; Hildebrandt, Martin

2004-06-01

We assessed changes of the enzyme dipeptidyl peptidase IV (DPP IV, CD26) in the context of leptin or leptin receptor deficiency. C57BL/6 mice, Leptin-deficient mice (ob/ob mice, B6.V-Lep) and Leptin-receptor-deficient mice (db/db mice, B6.Cg-m+/+Lepr) were infected with B. Calmette-Guerin (BCG) and sacrificed three days later. DPP IV activity in serum was higher in ob/ob mice and in db/db mice than in wild-type mice. The expression of DPP IV/CD26 on splenocytes was higher in ob/ob mice than in wild-type animals, and lower in db/db mice, and decreased upon stimulation with BCG in ob/ob mice only. Several T cell antigens including CTLA-4 were expressed aberrantly in ob/ob and in db/db mice. Our observations provide evidence for a relationship between DPP IV and leptin.

Lifestyle change in Kerala, India: needs assessment and planning for a community-based diabetes prevention trial

PubMed Central

2013-01-01

Background Type 2 Diabetes Mellitus (T2DM) has become a major public health challenge in India. Factors relevant to the development and implementation of diabetes prevention programmes in resource-constrained countries, such as India, have been under-studied. The purpose of this study is to describe the findings from research aimed at informing the development and evaluation of a Diabetes Prevention Programme in Kerala, India (K-DPP). Methods Data were collected from three main sources: (1) a systematic review of key research literature; (2) a review of relevant policy documents; and (3) focus groups conducted among individuals with a high risk of progressing to diabetes. The key findings were then triangulated and synthesised. Results Prevalence of risk factors for diabetes is very high and increasing in Kerala. This situation is largely attributable to rapid changes in the lifestyle of people living in this state of India. The findings from the systematic review and focus groups identified many environmental and personal determinants of these unhealthy lifestyle changes, including: less than ideal accessibility to and availability of health services; cultural values and norms; optimistic bias and other misconceptions related to risk; and low expectations regarding one’s ability to make lifestyle changes in order to influence health and disease outcomes. On the other hand, there are existing intervention trials conducted in India which suggests that risk reduction is possible. These programmes utilize multi-level strategies including mass media, as well as strategies to enhance community and individual empowerment. India’s national programme for the prevention and control of major non-communicable diseases (NCD) also provide a supportive environment for further community-based efforts to prevent diabetes. Conclusion These findings provide strong support for undertaking more research into the conduct of community-based diabetes prevention in the rural areas of Kerala. We aim to develop, implement and evaluate a group-based peer support programme that will address cultural and family determinants of lifestyle risks, including family decision-making regarding adoption of healthy dietary and physical activity patterns. Furthermore, we believe that this approach will be feasible, acceptable and effective in these communities; with the potential for scale-up in other parts of India. PMID:23375152

Effects of Inhibiting Dipeptidyl Peptidase-4 (DPP4) in Cows with Subclinical Ketosis

PubMed Central

Schulz, Kirsten; Frahm, Jana; Kersten, Susanne; Meyer, Ulrich; Rehage, Jürgen; Piechotta, Marion; Meyerholz, Maria; Breves, Gerhard; Reiche, Dania; Sauerwein, Helga; Dänicke, Sven

2015-01-01

The inhibition of dipeptidyl peptidase-4 (DPP4) via specific inhibitors is known to result in improved glucose tolerance and insulin sensitivity and decreased accumulation of hepatic fat in type II diabetic human patients. The metabolic situation of dairy cows can easily be compared to the status of human diabetes and non-alcoholic fatty liver. For both, insulin sensitivity is reduced, while hepatic fat accumulation increases, characterized by high levels of non-esterified fatty acids (NEFA) and ketone bodies.Therefore, in the present study, a DPP4 inhibitor was employed (BI 14332) for the first time in cows. In a first investigation BI 14332 treatment (intravenous injection at dosages of up to 3 mg/kg body weight) was well tolerated in healthy lactating pluriparous cows (n = 6) with a significant inhibition of DPP4 in plasma and liver. Further testing included primi- and pluriparous lactating cows suffering from subclinical ketosis (β-hydroxybutyrate concentrations in serum > 1.2 mM; n = 12). The intension was to offer effects of DPP4 inhibition during comprehensive lipomobilisation and hepatosteatosis. The cows of subclinical ketosis were evenly allocated to either the treatment group (daily injections, 0.3 mg BI 14332/kg body weight, 7 days) or the control group. Under condition of subclinical ketosis, the impact of DPP4 inhibition via BI 14332 was less, as in particular β-hydroxybutyrate and the hepatic lipid content remained unaffected, but NEFA and triglyceride concentrations were decreased after treatment. Owing to lower NEFA, the revised quantitative insulin sensitivity check index (surrogate marker for insulin sensitivity) increased. Therefore, a positive influence on energy metabolism might be quite possible. Minor impacts on immune-modulating variables were limited to the lymphocyte CD4+/CD8+ ratio for which a trend to decreased values in treated versus control animals was noted. In sum, the DPP4 inhibition in cows did not affect glycaemic control like it is shown in humans, but was able to impact hyperlipemia, as NEFA and TG decreased. PMID:26291537

Early and late effects of the DPP-4 inhibitor vildagliptin in a rat model of post-myocardial infarction heart failure

PubMed Central

2011-01-01

Background Progressive remodeling after myocardial infarction (MI) is a leading cause of morbidity and mortality. Recently, glucagon-like peptide (GLP)-1 was shown to have cardioprotective effects, but treatment with GLP-1 is limited by its short half-life. It is rapidly degraded by the enzyme dipeptidyl peptidase-4 (DPP-4), an enzyme which inhibits GLP-1 activity. We hypothesized that the DPP-4 inhibitor vildagliptin will increase levels of GLP-1 and may exert protective effects on cardiac function after MI. Methods Sprague-Dawley rats were either subjected to coronary ligation to induce MI and left ventricular (LV) remodeling, or sham operation. Parts of the rats with an MI were pre-treated for 2 days with the DPP-4 inhibitor vildagliptin (MI-Vildagliptin immediate, MI-VI, 15 mg/kg/day). The remainder of the rats was, three weeks after coronary artery ligation, subjected to treatment with DPP-4 inhibitor vildagliptin (MI-Vildagliptin Late, MI-VL) or control (MI). At 12 weeks, echocardiography and invasive hemodynamics were measured and molecular analysis and immunohistochemistry were performed. Results Vildagliptin inhibited the DPP-4 enzymatic activity by almost 70% and increased active GLP-1 levels by about 3-fold in plasma in both treated groups (p < 0.05 vs. non-treated groups). Cardiac function (ejection fraction) was decreased in all 3 MI groups compared with Sham group (p < 0.05); treatment with vildagliptin, either early or late, did not reverse cardiac remodeling. ANP (atrial natriuretic peptide) and BNP (brain natriuretic peptide) mRNA levels were significantly increased in all 3 MI groups, but no significant reductions were observed in both vildagliptin groups. Vildagliptin also did not change cardiomyocyte size or capillary density after MI. No effects were detected on glucose level and body weight in the post-MI remodeling model. Conclusion Vildagliptin increases the active GLP-1 level via inhibition of DPP-4, but it has no substantial protective effects on cardiac function in this well established long-term post-MI cardiac remodeling model. PMID:21955567

Short-term and long-term effects of dipeptidyl peptidase-4 inhibitors in type 2 diabetes mellitus patients with renal impairment: a meta-analysis of randomized controlled trials.

PubMed

Li, Ruifei; Wang, Rui; Li, Haixia; Sun, Sihao; Zou, Meijuan; Cheng, Gang

2016-09-01

To assess the short-term and long-term effects of dipeptidyl peptidase-4 (DPP-4) inhibitors in type 2 diabetes mellitus patients with renal impairment, a meta-analysis of randomized clinical trials of DPP-4 inhibitor interventions in type 2 diabetes mellitus patients with renal impairment was performed. PubMed, Embase, Cochrane Library and ClinicalTrials.gov were searched through the end of March 2015. Randomized clinical trials were selected if (1) DPP-4 inhibitors were compared with a placebo or other active-comparators, (2) the treatment duration was ≥12 weeks and (3) data regarding changes in haemoglobin A1c (HbA1c ), changes in fasting plasma glucose or hypoglycaemia and other adverse events were reported. Of 790 studies, ten studies on eight randomized clinical trials were included. Compared with the control group, DPP-4 inhibitors were associated with a greater HbA1c reduction in both the short-term [mean differences (MD) = -0.45, 95% confidence intervals (-0.57, -0.33), p < 0.0001] and long-term [MD = -0.33, 95% confidence intervals (-0.63, -0.03), p = 0.03] treatments. However, the long-term greater reduction in HbA1c with DPP-4 inhibitor treatment was only significant when the control treatment comprised placebo plus stable background treatment, but not glipizide plus stable background treatment. DPP-4 inhibitors were associated with a greater fasting plasma glucose reduction [MD = -12.59, 95% confidence intervals (-22.01, -3.17), p = 0.009] over the short-term; however, this effect was not present over the long-term. Regarding the hypoglycaemia adverse events assessment, the long-term treatment data indicated there was no increased risk of hypoglycaemia compared with placebo or active-controlled anti-diabetic drugs. The present meta-analysis confirms that DPP-4 inhibitors are effective and equivalent to other agents in type 2 diabetes mellitus patients with renal impairment. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Stabilization of enzymatically polymerized phenolic chemicals in a model soil organic matter-free geomaterial.

PubMed

Palomo, Mónica; Bhandari, Alok

2012-01-01

A variety of remediation methods, including contaminant transformation by peroxidase-mediated oxidative polymerization, have been proposed to manage soils and groundwater contaminated with chlorinated phenols. Phenol stabilization has been successfully observed during cross polymerization between phenolic polymers and soil organic matter (SOM) for soils with SOM >3%. This study evaluates peroxidase-mediated transformation and removal of 2,4-dichlorophenol (DCP) from an aqueous phase in contact with a natural geomaterial modified to contain negligible (<0.3%) SOM. The results are compared with those for soils with higher SOM. The SOM-free sorbent was generated by removing SOM using a NaOCl oxidation. When horseradish peroxidase (HRP) was used to induce polymerization of DCP, the soil-water phase distribution relationship (PDR) of DCP polymerization products (DPP) was complete within 1 d and PDRs did not significantly change over the 28 d of study. The conversion of DCP to DPP was close to 95% efficient. Extractable solute consisted entirely of DPP with 5% or less of unreacted DCP. The aqueous extractability of DPP from SOM-free geomaterial decreased at longer contact times and at smaller residual aqueous concentrations of DPP. DCP stabilization appeared to have resulted from a combination of sorption, precipitation, and ligand exchange between oligomeric products and the exposed mineral surfaces. Modification of the mineral surface through coverage with DPP enhanced the time-dependent retention of the oligomers. DPP stabilization in SOM-free geomaterial was comparable with that reported in the literature with soil containing SOM contents >1%. Results from this study suggest that the effectiveness of HRP-mediated stabilization of phenolic compounds not only depends on the cross-coupling with SOM, but also on the modification of the surface of the sorbent that can augment affinity with oligomers and enhance stabilization. Coverage of the mineral surface by phenolic oligomers may be analogous to SOM that can potentially sorb other xenobiotics. HRP- mediated reactions can be used to stabilize DCP associated with low SOM mineral soils or aquifer media, thereby restricting the transport of phenolic contaminants in the soil environment. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Stage of Change and Motivation to a Healthier Lifestyle before and after an Intensive Lifestyle Intervention.

PubMed

Livia, Buratta; Elisa, Reginato; Claudia, Ranucci; Roberto, Pippi; Cristina, Aiello; Emilia, Sbroma Tomaro; Chiara, Perrone; Alberto, Tirimagni; Angelo, Russo; Pierpaolo, De Feo; Claudia, Mazzeschi

2016-01-01

Lifestyle modification programs are different but typically include both nutritional aspects and physical activity as main domains with different behavioral and/or psychological strategies designed to affect change. A fundamental role in modifying unhealthy habits is played by personal motivation for change. The present study sought to investigate, in a group of 100 overweight/obese outpatients with and/or without TMD2, treatment seeking, the effect of an intensive lifestyle program on medical measures and motivational profile for physical activity (PA) and healthy nutrition (NUTR). Subjects participated in an intensive multidisciplinary lifestyle intervention at C.U.R.I.A.MO. Before and after the intervention, patients received a comprehensive evaluation of their clinical, anthropometric, and metabolic states and motivation to lifestyle changes. Data showed differences before and after intervention in both medical and motivational measures. Before the intervention patients reported to be ready, open, and determined to change and gave importance to healthy habits. After the intervention patients continued to be determined but increased the actions toward the change showing a higher degree of maintenance and of acquisition of habits especially in the physical domain of the new lifestyle. Data support the notion that the motivation should be followed during all the lifestyle interventions to support the change on both domains of the lifestyle program.

Inhibitory effect of collagen-derived tripeptides on dipeptidylpeptidase-IV activity.

PubMed

Hatanaka, Tadashi; Kawakami, Kayoko; Uraji, Misugi

2014-12-01

The collagen tripeptide fragments Gly-Ala-Hyp, Gly-Pro-Ala and Gly-Pro-Hyp were generated by hydrolyzing collagen from pig-skin, cattle-skin, fish-scales and chicken-feet, respectively, with Streptomyces collagenase. Collagenase treatment increased the concentration of tripeptides in the hydrolysates by 13-15% (w/w). Of the three peptides, Gly-Pro-Hyp was a true peptidic inhibitor of dipeptidylpeptidase-IV (DPP-IV), because DPP-IV could not hydrolyze the bond between Pro-Hyp. This tripeptide was a moderately competitive inhibitor (Ki=4.5 mM) of DPP-IV, and its level in the collagen hydrolysates could be greatly increased (4-9% [w/w]) using Streptomyces collagenase.

Characterization of Microporous Insulation, Microsil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, R.

Microsil microporous insulation has been characterized by Lawrence Livermore National Laboratory for possible use in structural and thermal applications in the DPP-1 design. Qualitative test results have provided mechanical behavioral characteristics for DPP-1 design studies and focused on the material behavioral response to being crushed, cyclically loaded, and subjected to vibration for a confined material with an interference fit or a radial gap. Quantitative test results have provided data to support the DPP-1 FEA model analysis and verification and were used to determine mechanical property values for the material under a compression load. The test results are documented within thismore » report.« less

ARTICLES: Microwave Assisted Synthesis of a New Triplet Iridium(III) Pyrazine Complex

NASA Astrophysics Data System (ADS)

Wu, Qiu-hua; Wang, Chuan-hong; Song, Xi-ming; Zhang, Guo-lin

2010-06-01

A new cyclometalated iridium(III) complex Ir(DPP)3 (DPP = 2,3-diphenylpyrazine) was prepared by reaction of DPP with iridium trichloride hydrate under microwave irradiation. The structure of the complex was confirmed by elemental analysis, 1H NMR, and mass spectroscopy. The UV-Vis absorption and photoluminescent properties of the complex were investigated. The complex shows strong 1MLCT (singlet metal to ligand charge-transfer) and 3MLCT (triplet metal to ligand charge-transfer) absorption at 382 and 504 nm, respectively. The complex also shows strong photoluminescence at 573 nm at room temperature. These results suggest the complex to be a promising phosphorescent material.

Synthesis, Characterization and TFT Characteristics of Diketopyrrolopyrrole Based Copolymer.

PubMed

Bathula, Chinna; Jeong, Seunghoon; Chung, Jeyon; Kang, Youngjong

2016-03-01

A novel diketopyrrolopyrrole (DPP) based low band gap polymer, poly[4,8-bis(triisopropylsilylethynyl) benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-[2,5-di-hexyl-3,6-dithiophen-2-ylpyrrolo[3,4-c]pyrrole-1,4-dione] (PTIPSBDT-DPP) is synthesized by Stille polymerization for use in thin film transistor (TFTs). The new polymer contain extended aromatic π-conjugated segments alternating with the DPP units and are designed to increase the free energy for charge generation to overcome current limitations in photocurrent generation. In this study we describe the synthesis, thermal stability, optical, electrochemical properties and TFT characteristics.

A lifestyle program of exercise and weight loss is effective in preventing and treating type 2 diabetes mellitus: Why are programs not more available?

PubMed

Ades, Philip A

2015-11-01

There is substantial evidence that type 2 diabetes mellitus (T2DM) can be prevented in high-risk individuals by a lifestyle program of regular exercise and weight reduction. Additionally, there is emerging evidence that new onset T2DM (<1year) can go into remission after weight loss and exercise in a majority of motivated individuals, obviating a need for glucose lowering medications. Yet, lifestyle programs to support such behavior change are not widely available. Moreover, health care insurance companies generally do not provide coverage for behavioral weight loss programs to prevent or treat T2DM. Consequently, physicians caring for individuals with T2DM may find it much easier to start a chronic glucose lowering medication rather than attempting to motivate and support patients through long-term behavior change. The cardiac rehabilitation model of disease management, with a network of over 2000 programs in the U.S., is well suited to deliver medically-supervised lifestyle programs. National organizations such as the American Diabetes Association and the American Association of Cardiovascular and Pulmonary Rehabilitation should support greater availability and use of lifestyle programs for T2DM treatment and prevention. Copyright © 2015 Elsevier Inc. All rights reserved.

30 CFR 550.272 - If a State objects to the DPP's or DOCD's coastal zone consistency certification, what can I do?

Code of Federal Regulations, 2012 CFR

2012-07-01

... OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Review and Decision Process for the Dpp Or Docd § 550.272...

30 CFR 550.272 - If a State objects to the DPP's or DOCD's coastal zone consistency certification, what can I do?

Code of Federal Regulations, 2013 CFR

2013-07-01

... OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Review and Decision Process for the Dpp Or Docd § 550.272...

Aminopiperidine-Fused Imidazoles as Dipeptidyl Peptidase-IV Inhibitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edmondson, S.; Mastracchio, A; Cox, J

2009-01-01

A new series of DPP-4 inhibitors derived from piperidine-fused benzimidazoles and imidazopyridines is described. Optimization of this class of DPP-4 inhibitors led to the discovery of imidazopyridine 34. The potency, selectivity, cross-species DMPK profiles, and in vivo efficacy of 34 is reported.

Factors Influencing the Prescribing Preferences of Physicians for Drug-Naive Patients with Type 2 Diabetes Mellitus in the Real-World Setting in Japan: Insight from a Web Survey.

PubMed

Murayama, Hiroki; Imai, Kota; Odawara, Masato

2018-06-01

The Japanese guidelines for type 2 diabetes mellitus (T2DM) emphasize individualization of treatment based on patient need and encourage physicians to select an appropriate oral antidiabetes drug (OAD). However, limited evidence is available on the factors influencing the selection by physicians (diabetes specialists and nonspecialists) of the first-line OAD to treat drug-naive patients with T2DM. A survey was designed to explore the treatment factors and patient characteristics that influence physicians when they choose an initial OAD to prescribe to a drug-naive patient with T2DM in a real-world setting in Japan. The 25-min web-based online survey consisted of simple and focused multiple-choice questions, and was circulated to physicians across eight selected regions in Japan. The primary endpoints were the proportions of physicians who considered particular treatment factors and patient characteristics when selecting the appropriate treatment for drug-naive T2DM patients. A total of 491 physicians participated in the survey. Dipeptidyl peptidase-4 inhibitors (DPP-4is) were the most-preferred first-line OADs, followed by metformin, of both specialists (69% vs. 60%) and nonspecialists (73% vs. 47%). The most influential factors when a DPP-4i was selected were found to be glycated hemoglobin (HbA1c), postprandial glucose (PPG)-lowering effect, and a low risk of hypoglycemia, which were considered by > 80% of physicians, whereas the key factors when metformin was selected were improvement in insulin resistance, low cost, low risk of hypoglycemia, and PPG- and HbA1c-lowering effects, which were considered by > 85% of physicians. Regression analysis revealed that the dominant reason for choosing DPP-4is over metformin was their ease of use in patients with renal impairment, whereas the dominant reasons for choosing metformin over DPP-4is were improvement in insulin resistance and low cost. The key patient characteristics driving the choice of DPP-4is or metformin as the first-line OAD by physicians were similar to those that influenced the treatment intensification decision (DPP-4is: PPG and renal function; metformin: age, BMI, insulin resistance, and renal function). In Japan, DPP-4is are the preferred first-line OADs, followed by metformin. The key treatment factors and patient characteristics considered when selecting DPP-4is or metformin are similar for both specialists and nonspecialists. These results may prompt further discussion of the differences in T2DM treatment between Japan and other counties. Novartis.

Structure-Property Relationships of Semiconducting Polymers for Flexible and Durable Polymer Field-Effect Transistors.

PubMed

Kim, Min Je; Jung, A-Ra; Lee, Myeongjae; Kim, Dongjin; Ro, Suhee; Jin, Seon-Mi; Nguyen, Hieu Dinh; Yang, Jeehye; Lee, Kyung-Koo; Lee, Eunji; Kang, Moon Sung; Kim, Hyunjung; Choi, Jong-Ho; Kim, BongSoo; Cho, Jeong Ho

2017-11-22

We report high-performance top-gate bottom-contact flexible polymer field-effect transistors (FETs) fabricated by flow-coating diketopyrrolopyrrole (DPP)-based and naphthalene diimide (NDI)-based polymers (P(DPP2DT-T2), P(DPP2DT-TT), P(DPP2DT-DTT), P(NDI2OD-T2), P(NDI2OD-F2T2), and P(NDI2OD-Se2)) as semiconducting channel materials. All of the polymers displayed good FET characteristics with on/off current ratios exceeding 10 7 . The highest hole mobility of 1.51 cm 2 V -1 s -1 and the highest electron mobility of 0.85 cm 2 V -1 s -1 were obtained from the P(DPP2DT-T2) and P(NDI2OD-Se2) polymer FETs, respectively. The impacts of the polymer structures on the FET performance are well-explained by the interplay between the crystallinity, the tendency of the polymer backbone to adopt an edge-on orientation, and the interconnectivity of polymer fibrils in the film state. Additionally, we demonstrated that all of the flexible polymer-based FETs were highly resistant to tensile stress, with negligible changes in their carrier mobilities and on/off ratios after a bending test. Conclusively, these high-performance, flexible, and durable FETs demonstrate the potential of semiconducting conjugated polymers for use in flexible electronic applications.

Phosphorylation regulates the secondary structure and function of dentin phosphoprotein peptides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Villarreal-Ramirez, Eduardo; Eliezer, David; Garduño-Juarez, Ramon

Dentin phosphoprotein (DPP) is the most acidic protein in vertebrates and structurally is classified as an intrinsically disordered protein. Functionally, DPP is related to dentin and bone formation, however the specifics of such association remain unknown. Here, we used atomistic molecular dynamics simulations to screen selected binding domains of DPP onto hydroxyapatite (HA), which is one of its important interacting partners. From these results, we selected a functionally relevant peptide, Ace-SSDSSDSSDSSDSSD-NH2 (named P5) and its phosphorylated form (named P5P), for experimental characterization. SAXS experiments indicated that in solution P5 was disordered, possibly in an extended conformation while P5P displayed moremore » compact globular conformations. Circular dichroism and FTIR confirmed that, either in the presence or absence of Ca2 +/HA, P5 adopts a random coil structure, whereas its phosphorylated counterpart, P5P, has a more compact arrangement associated with conformations that display β-sheet and α-helix motifs when bound to HA. In solution, P5 inhibited HA crystal growth, whereas at similar concentrations, P5P stimulated it. These findings suggest that phosphorylation controls the transient formation of secondary and tertiary structure of DPP peptides, and, most likely of DPP itself, which in turn controls HA growth in solution and possibly HA growth in mineralized tissues.« less

Dipeptidyl Peptidase-4 Inhibitor Development and Post-authorisation Programme for Vildagliptin - Clinical Evidence for Optimised Management of Chronic Diseases Beyond Type 2 Diabetes.

PubMed

Strain, William David; Paldánius, Päivi M

2017-08-01

The last decade has witnessed the role of dipeptidyl peptidase-4 (DPP-4) inhibitors in producing a conceptual change in early management of type 2 diabetes mellitus (T2DM) by shifting emphasis from a gluco-centric approach to holistically treating underlying pathophysiological processes. DPP-4 inhibitors highlighted the importance of acknowledging hypoglycaemia and weight gain as barriers to optimised care in T2DM. These complications were an integral part of diabetes management before the introduction of DPP-4 inhibitors. During the development of DPP-4 inhibitors, regulatory requirements for introducing new agents underwent substantial changes, with increased emphasis on safety. This led to the systematic collection of adjudicated cardiovascular (CV) safety data, and, where 95% confidence of a lack of harm could not be demonstrated, the standardised CV safety studies. Furthermore, the growing awareness of the worldwide extent of T2DM demanded a more diverse approach to recruitment and participation in clinical trials. Finally, the global financial crisis placed a new awareness on the health economics of diabetes, which rapidly became the most expensive disease in the world. This review encompasses unique developments in the global landscape, and the role DPP-4 inhibitors, specifically vildagliptin, have played in research advancement and optimisation of diabetes care in a diverse population with T2DM worldwide.

Dipeptidyl Peptidase-4 Inhibitor Development and Post-authorisation Programme for Vildagliptin — Clinical Evidence for Optimised Management of Chronic Diseases Beyond Type 2 Diabetes

PubMed Central

Paldánius, Päivi M

2017-01-01

Abstract The last decade has witnessed the role of dipeptidyl peptidase-4 (DPP-4) inhibitors in producing a conceptual change in early management of type 2 diabetes mellitus (T2DM) by shifting emphasis from a gluco-centric approach to holistically treating underlying pathophysiological processes. DPP-4 inhibitors highlighted the importance of acknowledging hypoglycaemia and weight gain as barriers to optimised care in T2DM. These complications were an integral part of diabetes management before the introduction of DPP-4 inhibitors. During the development of DPP-4 inhibitors, regulatory requirements for introducing new agents underwent substantial changes, with increased emphasis on safety. This led to the systematic collection of adjudicated cardiovascular (CV) safety data, and, where 95% confidence of a lack of harm could not be demonstrated, the standardised CV safety studies. Furthermore, the growing awareness of the worldwide extent of T2DM demanded a more diverse approach to recruitment and participation in clinical trials. Finally, the global financial crisis placed a new awareness on the health economics of diabetes, which rapidly became the most expensive disease in the world. This review encompasses unique developments in the global landscape, and the role DPP-4 inhibitors, specifically vildagliptin, have played in research advancement and optimisation of diabetes care in a diverse population with T2DM worldwide. PMID:29632609

Effectiveness of the Complete Health Improvement Program

ERIC Educational Resources Information Center

Hutchins, Mathew; Melancon, Jim; Sneed, Demarcus; Nunning, Jennifer

2015-01-01

Currently, heart disease and diabetes dominate society as the leading cause of death for Americans. In this study, we examined the effectiveness of a lifestyle enhancement program on factors related to the development of heart disease. The Wabash Valley Complete Health Improvement Program (CHIP) is a community-based lifestyle change program with…

Evaluation of a Digital Behavioral Counseling Program for Reducing Risk Factors for Chronic Disease in a Workforce.

PubMed

Wilson, Mark G; Castro Sweet, Cynthia M; Edge, Michael D; Madero, Erica N; McGuire, Megan; Pilsmaker, Megan; Carpenter, Dan; Kirschner, Scott

2017-08-01

To evaluate a digitally delivered, intensive behavioral counseling program for a workforce at risk for obesity-related chronic disease. Employees were offered a digital health program modeled after the diabetes prevention program (DPP). Annual workforce health assessments were used to examine changes in chronic disease risk factors between participants (n = 634) relative to a matched comparison group (n = 1268). Overall, employees were gaining an average of 3.5 pounds annually before program inception. Program engagement was positive; 83% completed the majority of the curriculum and 31% lost at least 5% of their starting weight. Compared with non-participating peers, participants demonstrated reduced weight, improved fasting blood glucose, and improved nutritional intake after a year. The digital health program was effective for engaging employees in health behavior change. Digital options facilitate widespread implementation.

30 CFR 250.252 - What environmental monitoring information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What environmental monitoring information must... Development Operations Coordination Documents (docd) § 250.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must accompany...

Dipeptidyl peptidase 4 – an important digestive peptidase in Tenebrio molitor larvae

USDA-ARS?s Scientific Manuscript database

Dipeptidyl peptidase 4 (DPP 4) is a proline specific serine peptidase that plays an important role in different regulatory processes in mammals. In this report, we isolated and characterized a unique secreted digestive DPP 4 from the anterior midgut of a stored product pest, Tenebrio molitor larvae ...

30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development Operations Coordination Documents (docd) § 550.246 What mineral resource conservation information must... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What mineral resource conservation information...

30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development Operations Coordination Documents (docd) § 550.246 What mineral resource conservation information must... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What mineral resource conservation information...

30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... SHELF Plans and Information Contents of Development and Production Plans (dpp) and Development Operations Coordination Documents (docd) § 550.246 What mineral resource conservation information must... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What mineral resource conservation information...

30 CFR 550.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... information must accompany the DPP or DOCD? 550.247 Section 550.247 Mineral Resources BUREAU OF OCEAN ENERGY... information on chemosynthetic communities, federally listed threatened or endangered species, marine mammals protected under the MMPA, sensitive underwater features, marine sanctuaries, critical habitat designated...

30 CFR 550.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... information must accompany the DPP or DOCD? 550.247 Section 550.247 Mineral Resources BUREAU OF OCEAN ENERGY... information on chemosynthetic communities, federally listed threatened or endangered species, marine mammals protected under the MMPA, sensitive underwater features, marine sanctuaries, critical habitat designated...

30 CFR 550.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... information must accompany the DPP or DOCD? 550.247 Section 550.247 Mineral Resources BUREAU OF OCEAN ENERGY... information on chemosynthetic communities, federally listed threatened or endangered species, marine mammals protected under the MMPA, sensitive underwater features, marine sanctuaries, critical habitat designated...

A Healthy Lifestyle Program for Latino Daughters and Mothers: The BOUNCE Overview and Process Evaluation

ERIC Educational Resources Information Center

Olvera, Norma N.; Knox, Brook; Scherer, Rhonda; Maldonado, Gabriela; Sharma, Shreela V.; Alastuey, Lisa; Bush, Jill A.

2008-01-01

Background: Few family-based healthy lifestyle programs for Latinos have been conducted, especially family programs targeting mother-daughter dyads. Purpose: To assess the acceptability and feasibility of the Behavior Opportunities Uniting Nutrition Counseling and Exercise (BOUNCE) program designed for Latino mother-daughter pairs. Methods: 92…

EUV near normal incidence collector development at SAGEM

NASA Astrophysics Data System (ADS)

Mercier Ythier, R.; Bozec, X.; Geyl, R.; Rinchet, A.; Hecquet, Christophe; Ravet-Krill, Marie-Françoise; Delmotte, Franck; Sassolas, Benoît; Flaminio, Raffaele; Mackowski, Jean-Marie; Michel, Christophe; Montorio, Jean-Luc; Morgado, Nazario; Pinard, Laurent; Roméo, Elodie

2008-03-01

Through its participation to European programs, SAGEM has worked on the design and manufacturing of normal incidence collectors for EUV sources. By opposition to grazing incidence, normal incidence collectors are expected to collect more light with a simpler and cheaper design. Designs are presented for the two current types of existing sources: Discharge Produced Plasma (DPP) and Laser Produced Plasma (LPP). Collection efficiency is calculated in both cases. It is shown that these collectors can achieve about 10 % efficiency for DPP sources and 40 % for LPP sources. SAGEM works on the collectors manufacturability are also presented, including polishing, coating and cooling. The feasibility of polishing has been demonstrated with a roughness better than 2 angstroms obtained on several materials (glass, silicon, Silicon Carbide, metals...). SAGEM is currently working with the Institut d'Optique and the Laboratoire des Materiaux Avancés on the design and the process of EUV coatings for large mirrors. Lastly, SAGEM has studied the design and feasibility of an efficient thermal control, based on a liquid cooling through slim channels machined close to the optical surface.

Stage of Change and Motivation to a Healthier Lifestyle before and after an Intensive Lifestyle Intervention

PubMed Central

Livia, Buratta; Elisa, Reginato; Claudia, Ranucci; Roberto, Pippi; Cristina, Aiello; Emilia, Sbroma Tomaro; Chiara, Perrone; Alberto, Tirimagni; Angelo, Russo; Pierpaolo, De Feo; Claudia, Mazzeschi

2016-01-01

Objective. Lifestyle modification programs are different but typically include both nutritional aspects and physical activity as main domains with different behavioral and/or psychological strategies designed to affect change. A fundamental role in modifying unhealthy habits is played by personal motivation for change. The present study sought to investigate, in a group of 100 overweight/obese outpatients with and/or without TMD2, treatment seeking, the effect of an intensive lifestyle program on medical measures and motivational profile for physical activity (PA) and healthy nutrition (NUTR). Method. Subjects participated in an intensive multidisciplinary lifestyle intervention at C.U.R.I.A.MO. Before and after the intervention, patients received a comprehensive evaluation of their clinical, anthropometric, and metabolic states and motivation to lifestyle changes. Results. Data showed differences before and after intervention in both medical and motivational measures. Before the intervention patients reported to be ready, open, and determined to change and gave importance to healthy habits. After the intervention patients continued to be determined but increased the actions toward the change showing a higher degree of maintenance and of acquisition of habits especially in the physical domain of the new lifestyle. Conclusion. Data support the notion that the motivation should be followed during all the lifestyle interventions to support the change on both domains of the lifestyle program. PMID:27239339

[Posterior polymorphous dystrophy, case report and literature review].

PubMed

Mendoza-Adam, G; Hernandez-Camarena, J C; Valdez-García, J E

2015-09-01

Posterior Polymorphous Dystrophy (DPP) is a rare posterior corneal dystrophy that is genetically transmitted as autosomal dominant. Corneal structures affected in this dystrophy are Descemet membrane and the endothelium. A case is presented on a 47 years old woman with no relevant history, with typical findings of DPP (vesicular and band lesions at the endothelium and posterior Descemet). To our knowledge there are no reported cases of DPP in Latin-American patients in the literature. The clinical manifestations in our patient were found to be very similar to the cases reported in other populations. Copyright © 2014 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Unveiling the mechanisms of dressed-photon-phonon etching based on hierarchical surface roughness measure

NASA Astrophysics Data System (ADS)

Naruse, Makoto; Yatsui, Takashi; Nomura, Wataru; Kawazoe, Tadashi; Aida, Masaki; Ohtsu, Motoichi

2013-02-01

Dressed-photon-phonon (DPP) etching is a disruptive technology in planarizing material surfaces because it completely eliminates mechanical contact processes. However, adequate metrics for evaluating the surface roughness and the underlying physical mechanisms are still not well understood. Here, we propose a two-dimensional hierarchical surface roughness measure, inspired by the Allan variance, that represents the effectiveness of DPP etching while conserving the original two-dimensional surface topology. Also, we build a simple physical model of DPP etching that agrees well with the experimental observations, which clearly shows the involvement of the intrinsic hierarchical properties of dressed photons, or optical near-fields, in the surface processing.

Technology and Changing Lifestyles. Teacher's Guide. Preparing for Tomorrow's World.

ERIC Educational Resources Information Center

Iozzi, Louis A.

"Technology and Changing Lifestyles" is one of the "Preparing for Tomorrow's World" (PTW) program modules. PTW is an interdisciplinary, future-oriented program incorporating information from the sciences and social sciences and addressing societal concerns which interface science/technology/society. The program promotes…

Assessing Sustainability of Lifestyle Education for Activity Program (LEAP)

ERIC Educational Resources Information Center

Saunders, R. P.; Pate, R. R.; Dowda, M.; Ward, D. S.; Epping, J. N.; Dishman, R. K.

2012-01-01

Sustained intervention effects are needed for positive health impacts in populations; however, few published examples illustrate methods for assessing sustainability in health promotion programs. This paper describes the methods for assessing sustainability of the Lifestyle Education for Activity Program (LEAP). LEAP was a comprehensive…

Meals, Mindfulness, & Moving Forward: A feasibility study to a multi-modal lifestyle approach in early psychosis.

PubMed

Usher, Craigan; Thompson, Andie; Griebeler, Meridith; Senders, Angela; Seibel, Celeste; Ly, Richard; Murchison, Charles; Hagen, Kirsten; Afong, Keith-Allen; Bourdette, Dennis; Ross, Rachel; Borgatti, Alena; Shinto, Lynne

2018-03-07

The primary aim was to demonstrate adherence to a novel 6-week lifestyle intervention program ("Meals, Mindfulness, & Moving Forward" [M 3 ]) designed to help improve lifestyle practices of youth with a history of at least 1 psychotic episode. M 3 used a non-equivalent control group design involving clients from a community early intervention program. Seventeen individuals in the active M 3 program and 16 controls were assessed for secondary outcomes at baseline, 6-weeks, and 12-weeks (6 weeks post-intervention) on cardiometabolic and symptomatic outcomes. The program met its primary aim with 88% (15/17) of participants meeting adherence criteria. Compared with the controls, M 3 participants showed significant improvement in positive psychotic symptoms (P = .002). This pilot study showed that young people involved in a community early intervention program adhered to an activity-based lifestyle program which included mindfulness meditation, yoga and nutrition education, warranting further evaluation with a larger sample size. © 2018 John Wiley & Sons Australia, Ltd.

Sociocultural Tailoring of a Healthy Lifestyle Intervention to Reduce Cardiovascular Disease and Type 2 Diabetes Risk Among Latinos

PubMed Central

Martinez, Maria C.; Rayens, Mary Kay; Gokun, Yevgeniya; Meininger, Janet C.

2013-01-01

Background Suboptimal lifestyle factors in combination with genetic susceptibility contribute to cardiovascular disease and type 2 diabetes risk among Latinos. We describe a community–academic collaboration that developed and explored the feasibility of implementing a socioculturally tailored, healthy lifestyle intervention integrating genomics and family history education to reduce risk of cardiovascular disease and type 2 diabetes among Latinos. Community Context The community-based participatory research was conducted with communities in Kentucky, which has a rapidly growing Latino population. This growth underscores the need for socioculturally appropriate health resources. Methods Su Corazon, Su Vida (Your Heart, Your Life) is a Spanish-language, healthy lifestyle educational program to reduce cardiovascular disease and type 2 diabetes risk among Latinos. Twenty natural leaders from an urban Latino community in Kentucky participated in sociocultural tailoring of the program and development of a genomics and family history module. The tailored program was presented to 22 participants to explore implementation feasibility and assess appropriateness for community use. Preintervention and postintervention assessments of genomic knowledge and lifestyle behaviors and qualitative postintervention evaluations were conducted. Outcomes Postintervention improvements in health-promoting lifestyle choices and genomic knowledge specific to cardiovascular disease and type 2 diabetes suggested that the program may be effective in reducing risk. Feedback indicated the program was socioculturally acceptable and responsive to community needs. Interpretation These findings indicated that a tailored healthy lifestyle program integrating genomics and family history education was socioculturally appropriate and may feasibly be implemented to reduce cardiovascular disease and type 2 diabetes risk in a Latino community with limited health care resources. The project highlights contributions of community-based processes in tailoring interventions that are appropriate for community contexts. PMID:24286274

Sociocultural tailoring of a healthy lifestyle intervention to reduce cardiovascular disease and type 2 diabetes risk among Latinos.

PubMed

Mudd-Martin, Gia; Martinez, Maria C; Rayens, Mary Kay; Gokun, Yevgeniya; Meininger, Janet C

2013-11-27

Suboptimal lifestyle factors in combination with genetic susceptibility contribute to cardiovascular disease and type 2 diabetes risk among Latinos. We describe a community-academic collaboration that developed and explored the feasibility of implementing a socioculturally tailored, healthy lifestyle intervention integrating genomics and family history education to reduce risk of cardiovascular disease and type 2 diabetes among Latinos. The community-based participatory research was conducted with communities in Kentucky, which has a rapidly growing Latino population. This growth underscores the need for socioculturally appropriate health resources. Su Corazon, Su Vida (Your Heart, Your Life) is a Spanish-language, healthy lifestyle educational program to reduce cardiovascular disease and type 2 diabetes risk among Latinos. Twenty natural leaders from an urban Latino community in Kentucky participated in sociocultural tailoring of the program and development of a genomics and family history module. The tailored program was presented to 22 participants to explore implementation feasibility and assess appropriateness for community use. Preintervention and postintervention assessments of genomic knowledge and lifestyle behaviors and qualitative postintervention evaluations were conducted. Postintervention improvements in health-promoting lifestyle choices and genomic knowledge specific to cardiovascular disease and type 2 diabetes suggested that the program may be effective in reducing risk. Feedback indicated the program was socioculturally acceptable and responsive to community needs. These findings indicated that a tailored healthy lifestyle program integrating genomics and family history education was socioculturally appropriate and may feasibly be implemented to reduce cardiovascular disease and type 2 diabetes risk in a Latino community with limited health care resources. The project highlights contributions of community-based processes in tailoring interventions that are appropriate for community contexts.

30 CFR 250.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... you request that the Regional Supervisor classify the area of your proposed development and production... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination... concentration of any H2S you might encounter or handle while you conduct your proposed development and...

30 CFR 250.242 - What information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

....258; (q) Sulphur operations information required by § 250.259; (r) Coastal zone management information... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What information must accompany the DPP or DOCD? 250.242 Section 250.242 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR...

30 CFR 550.243 - What general information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination... unusual technology (see definition under § 550.200) you will use to carry out your proposed development... matter of the omitted information. If you will not use any new or unusual technology to carry out your...

30 CFR 550.243 - What general information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination... unusual technology (see definition under § 550.200) you will use to carry out your proposed development... matter of the omitted information. If you will not use any new or unusual technology to carry out your...

30 CFR 550.243 - What general information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... Information Contents of Development and Production Plans (dpp) and Development Operations Coordination... unusual technology (see definition under § 550.200) you will use to carry out your proposed development... matter of the omitted information. If you will not use any new or unusual technology to carry out your...

30 CFR 250.254 - What mitigation measures information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What mitigation measures information must accompany the DPP or DOCD? 250.254 Section 250.254 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... take of: (1) Threatened and endangered species listed under the ESA and (2) Marine mammals, as...

30 CFR 250.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What biological, physical, and socioeconomic information must accompany the DPP or DOCD? 250.247 Section 250.247 Mineral Resources BUREAU OF OCEAN ENERGY... species, marine mammals protected under the MMPA, sensitive underwater features, marine sanctuaries...

30 CFR 250.249 - What air emissions information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... the DPP or DOCD? 250.249 Section 250.249 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT...) The total annual emissions in tons per year; (iii) Emissions over the duration of the proposed development and production activities; (iv) The frequency and duration of emissions; and (v) The total of all...

30 CFR 250.243 - What general information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... or DOCD? 250.243 Section 250.243 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... production activities, include a statement so indicating. (f) Bonds, oil spill financial responsibility, and... DPP or DOCD are or will be covered by an appropriate bond under 30 CFR part 256, subpart I; (2) You...

30 CFR 550.259 - What sulphur operations information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What sulphur operations information must accompany the DPP or DOCD? 550.259 Section 550.259 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... toxic or thermal impacts on the environment caused by the discharge of bleedwater. (b) Subsidence. An...

30 CFR 550.259 - What sulphur operations information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What sulphur operations information must accompany the DPP or DOCD? 550.259 Section 550.259 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... toxic or thermal impacts on the environment caused by the discharge of bleedwater. (b) Subsidence. An...

30 CFR 250.261 - What environmental impact analysis (EIA) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Operations Coordination Documents (docd) § 250.261 What environmental impact analysis (EIA) information must... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What environmental impact analysis (EIA) information must accompany the DPP or DOCD? 250.261 Section 250.261 Mineral Resources MINERALS MANAGEMENT...

Diketopyrrolopyrrole Polymers with Thienyl and Thiazolyl Linkers for Application in Field-Effect Transistors and Polymer Solar Cells.

PubMed

Yu, Yaping; Wu, Yang; Zhang, Andong; Li, Cheng; Tang, Zheng; Ma, Wei; Wu, Yonggang; Li, Weiwei

2016-11-09

Conjugated polymers consisting of diketopyrrolopyrrole (DPP) units have been successfully applied in field-effect transistors (FETs) and polymer solar cells (PSCs), while most of the DPP polymers were designed as symmetric structures containing identical aromatic linkers. In this manuscript, we design a new asymmetric DPP polymer with varied aromatic linkers in the backbone for application in FETs and PSCs. The designation provides the chance to finely adjust the energy levels of conjugated polymers so as to influence the device performance. The asymmetric polymer exhibits highly crystalline properties, high hole mobilities of 3.05 cm 2 V -1 s -1 in FETs, and a high efficiency of 5.9% in PSCs with spectra response from 300 to 850 nm. Morphology investigation demonstrates that the asymmetric polymer has a large crystal domain in blended thin films, indicating that the solar cell performance can be further enhanced by optimizing the microphase separation. The study reveals that the asymmetric design via adjusting the aromatic linkers in DPP polymers is a useful route toward flexible electronic devices.

DPP8 and DPP9 inhibition induces pro-caspase-1-dependent monocyte and macrophage pyroptosis.

PubMed

Okondo, Marian C; Johnson, Darren C; Sridharan, Ramya; Go, Eun Bin; Chui, Ashley J; Wang, Mitchell S; Poplawski, Sarah E; Wu, Wengen; Liu, Yuxin; Lai, Jack H; Sanford, David G; Arciprete, Michael O; Golub, Todd R; Bachovchin, William W; Bachovchin, Daniel A

2017-01-01

Val-boroPro (Talabostat, PT-100), a nonselective inhibitor of post-proline cleaving serine proteases, stimulates mammalian immune systems through an unknown mechanism of action. Despite this lack of mechanistic understanding, Val-boroPro has attracted substantial interest as a potential anticancer agent, reaching phase 3 trials in humans. Here we show that Val-boroPro stimulates the immune system by triggering a proinflammatory form of cell death in monocytes and macrophages known as pyroptosis. We demonstrate that the inhibition of two serine proteases, DPP8 and DPP9, activates the pro-protein form of caspase-1 independent of the inflammasome adaptor ASC. Activated pro-caspase-1 does not efficiently process itself or IL-1β but does cleave and activate gasdermin D to induce pyroptosis. Mice lacking caspase-1 do not show immune stimulation after treatment with Val-boroPro. Our data identify what is to our knowledge the first small molecule that induces pyroptosis and reveals a new checkpoint that controls the activation of the innate immune system.

Novel Dehalogenase Mechanism for 2,3-Dichloro-1-Propanol Utilization in Pseudomonas putida Strain MC4

PubMed Central

Arif, Muhammad Irfan; Samin, Ghufrana; van Leeuwen, Jan G. E.; Oppentocht, Jantien

2012-01-01

A Pseudomonas putida strain (MC4) that can utilize 2,3-dichloro-1-propanol (DCP) and several aliphatic haloacids and haloalcohols as sole carbon and energy source for growth was isolated from contaminated soil. Degradation of DCP was found to start with oxidation and concomitant dehalogenation catalyzed by a 72-kDa monomeric protein (DppA) that was isolated from cell lysate. The dppA gene was cloned from a cosmid library and appeared to encode a protein equipped with a signal peptide and that possessed high similarity to quinohemoprotein alcohol dehydrogenases (ADHs), particularly ADH IIB and ADH IIG from Pseudomonas putida HK. This novel dehalogenating dehydrogenase has a broad substrate range, encompassing a number of nonhalogenated alcohols and haloalcohols. With DCP, DppA exhibited a kcat of 17 s−1. 1H nuclear magnetic resonance experiments indicated that DCP oxidation by DppA in the presence of 2,6-dichlorophenolindophenol (DCPIP) and potassium ferricyanide [K3Fe(CN)6] yielded 2-chloroacrolein, which was oxidized to 2-chloroacrylic acid. PMID:22752160

Potential use of bitter melon (Momordica charantia) derived compounds as antidiabetics: In silico and in vivo studies.

PubMed

Elekofehinti, Olusola Olalekan; Ariyo, Esther Opeyemi; Akinjiyan, Moses Orimoloye; Olayeriju, Olanrewaju Sam; Lawal, Akeem Olalekan; Adanlawo, Isaac Gbadura; Rocha, Joao Batista Teixeira

2018-05-12

Momordica charantia (bitter lemon) belongs to the cucurbitaceae family which has been extensively used in traditional medicines for the cure of various ailments such as cancer and diabetes. The underlying mechanism of M. charantia to maintain glycemic control was investigated. GLP-1 and DPP-4 gene modulation by M. charantia (5-20% inclusion in rats diet) was investigated in vivo by RT-PCR and possible compounds responsible for diabetic action predicted through in silico approach. Phytochemicalss previously characterized from M. charantia were docked into glucacon like peptide-1 receptor (GLP-1r), dipeptidyl peptidase (DPP4) and Takeda-G-protein-receptor-5 (TGR5) predicted using Autodock Vina. The results of the in silico suggests momordicosides D (ligand for TGR5), cucurbitacin (ligand for GLP-1r) and charantin (ligand for DPP-4) as the major antidiabetic compounds in bitter lemon leaf. M. charantia increased the expression of GLP-1 by about 295.7% with concomitant decreased in expression of DPP-4 by 87.2% with 20% inclusion in rat's diet. This study suggests that the mechanism underlying the action of these compounds is through activation of TGR5 and GLP-1 receptor with concurrent inhibition of DPP4. This study confirmed the use of this plant in diabetes management and the possible bioactive compounds responsible for its antidiabetic property are charantin, cucurbitacin and momordicoside D and all belong to the class of saponins. Copyright © 2018 Elsevier B.V. All rights reserved.

Association of dipeptidyl peptidase 4 inhibitors with risk of metastases in patients with type 2 diabetes and breast, prostate or digestive system cancer.

PubMed

Rathmann, Wolfgang; Kostev, Karel

2017-04-01

Experimental and animal studies have supported the hypothesis that dipeptidyl peptidase-4 inhibitors (DPP-4i) may accelerate tumor metastasis. The aim was to analyze the relationships between DPP-4i therapy with risk of metastases in type 2 diabetes patients with breast, prostate and digestive organ cancers. Type 2 diabetes patients with first diagnoses of breast, prostate or digestive organ cancer were selected in general and internal medicine practices (Disease Analyzer Germany: 01/2008-12/2014). Propensity score matching between DPP-4i users and non-users was carried out for age, sex, diabetes duration, and metformin use. Time-dependent Cox regression models were used to estimate hazard ratios (HR) for metastases further adjusting for HbA1c, body mass index, comorbidity and co-therapy with glucose-lowering drugs (3-4years follow-up). 668 patients with newly diagnosed breast cancer, 906 with prostate cancer and 908 with digestive organ cancer were analyzed. In Cox regression, use of DPP-4i was not associated with an increased risk of metastases in patients with breast (adjusted HR, 95%CI: 1.00, 0.49-2.02), prostate (0.98, 0.54-1.77) or digestive organ cancers (0.97, 0.57-1.66). This first observational study in patients with type 2 diabetes and breast, prostate or digestive organ cancer found no increased risk of metastases in DPP-4i users. Copyright © 2017 Elsevier Inc. All rights reserved.

Type of Resection (Whipple vs. Distal) Does Not Affect the National Failure to Provide Post-resection Adjuvant Chemotherapy in Localized Pancreatic Cancer.

PubMed

Bergquist, John R; Ivanics, Tommy; Shubert, Christopher R; Habermann, Elizabeth B; Smoot, Rory L; Kendrick, Michael L; Nagorney, David M; Farnell, Michael B; Truty, Mark J

2017-06-01

Adjuvant chemotherapy improves survival after curative intent resection for localized pancreatic adenocarcinoma (PDAC). Given the differences in perioperative morbidity, we hypothesized that patients undergoing distal partial pancreatectomy (DPP) would receive adjuvant therapy more often those undergoing pancreatoduodenectomy (PD). The National Cancer Data Base (2004-2012) identified patients with localized PDAC undergoing DPP and PD, excluding neoadjuvant cases, and factors associated with receipt of adjuvant therapy were identified. Overall survival (OS) was analyzed using multivariable Cox proportional hazards regression. Overall, 13,501 patients were included (DPP, n = 1933; PD, n = 11,568). Prognostic characteristics were similar, except DPP patients had fewer N1 lesions, less often positive margins, more minimally invasive resections, and shorter hospital stay. The proportion of patients not receiving adjuvant chemotherapy was equivalent (DPP 33.7%, PD 32.0%; p = 0.148). The type of procedure was not independently associated with adjuvant chemotherapy (hazard ratio 0.96, 95% confidence interval 0.90-1.02; p = 0.150), and patients receiving adjuvant chemotherapy had improved unadjusted and adjusted OS compared with surgery alone. The type of resection did not predict adjusted mortality (p = 0.870). Receipt of adjuvant chemotherapy did not vary by type of resection but improved survival independent of procedure performed. Factors other than type of resection appear to be driving the nationwide rates of post-resection adjuvant chemotherapy in localized PDAC.

Response surface methodology applied to the generation of casein hydrolysates with antioxidant and dipeptidyl peptidase IV inhibitory properties.

PubMed

Nongonierma, Alice B; Maux, Solène Le; Esteveny, Claire; FitzGerald, Richard J

2017-03-01

Hydrolysis parameters affecting the release of dipeptidyl peptidase IV (DPP-IV) inhibitory and antioxidant peptides from milk proteins have not been extensively studied. Therefore, a multifactorial (i.e. pH, temperature and hydrolysis time) composite design was used to optimise the release of bioactive peptides (BAPs) with DPP-IV inhibitory and antioxidant [oxygen radical absorbance capacity (ORAC)] properties from sodium caseinate. Fifteen sodium caseinate hydrolysates (H1-H15) were generated with Protamex TM , a bacillus proteinase activity. Hydrolysis time (1 to 5 h) had the highest influence on both DPP-IV inhibitory properties and ORAC activity (P < 0.05). Alteration of incubation temperature (40 to 60 °C) and pH (6.5 to 8.0) had an effect on the DPP-IV inhibitory properties but not the ORAC activity of the Protamex sodium caseinate hydrolysates. A multi-functional hydrolysate, H12, was identified having DPP-IV inhibitory (actual: 0.82 ± 0.24 vs. predicted optimum: 0.68 mg mL -1 ) and ORAC (actual: 639 ± 66 vs. predicted optimum: 639 µmol TE g -1 ) activity of the same order (P > 0.05) as the response surface methodology (RSM) predicted optimum bioactivities. Generation of milk protein hydrolysates through multifactorial design approaches may aid in the optimal enzymatic release of BAPs with serum glucose lowering and antioxidant properties. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

The dorsoventral patterning of Musca domestica embryos: insights into BMP/Dpp evolution from the base of the lower cyclorraphan flies.

PubMed

Hodar, Christian; Cambiazo, Verónica

2018-01-01

In the last few years, accumulated information has indicated that the evolution of an extra-embryonic membrane in dipterans was accompanied by changes in the gene regulatory network controlled by the BMP/Dpp pathway, which is responsible for dorsal patterning in these insects. However, only comparative analysis of gene expression levels between distant species with two extra-embryonic membranes, like A. gambiae or C. albipunctata , and D. melanogaster, has been conducted. Analysis of gene expression in ancestral species, which evolved closer to the amnioserosa origin, could provide new insights into the evolution of dorsoventral patterning in dipterans. Here we describe the spatial expression of several key and downstream elements of the Dpp pathway and show the compared patterns of expression between Musca and Drosophila embryos, both dipterans with amnioserosa. Most of the analyzed gene showed a high degree of expression conservation, however, we found several differences in the gene expression pattern of M. domestica orthologs for sog and tolloid . Bioinformatics analysis of the promoter of both genes indicated that the variations could be related to the gain of several binding sites for the transcriptional factor Dorsal in the Md.tld promoter and Snail in the Md.sog enhancer . These altered expressions could explain the unclear formation of the pMad gradient in the M. domestica embryo, compared to the formation of the gradient in D. melanogaster. Gene expression changes during the dorsal-ventral patterning in insects contribute to the differentiation of extra-embryonic tissues as a consequence of changes in the gene regulatory network controlled by BMP/Dpp. In this work, in early M. domestica embryos, we identified the expression pattern of several genes members involved in the dorsoventral specification of the embryo. We believe that these data can contribute to understanding the evolution of the BMP/Dpp pathway, the regulation of BMP ligands, and the formation of a Dpp gradient in higher cyclorraphan flies.

Concordance with prescribing information dosage recommendations for dipeptidyl-peptidase-4 inhibitors among type 2 diabetes mellitus patients with moderate to severe chronic kidney disease.

PubMed

Huang, Huan; Shetty, Sharash; Bauer, Elise; Lang, Kathleen

2018-06-01

To estimate the proportion of patients with moderate to severe chronic kidney disease (CKD) whose initial dipeptidyl-peptidase-4 inhibitor (DPP4-i) dosage was concordant with prescribing information (label) recommendations in the United States. Adult patients with type 2 diabetes mellitus (T2DM) who initiated a DPP4-i (linagliptin, sitagliptin, saxagliptin) between 1 January 2011 and 30 June 2014 were identified using electronic medical records and administrative claims, with index date being the date of first observed DPP4-i treatment. Patients were required to have chronic kidney disease (CKD) stage 3b, 4 or 5 (estimated Glomerular Filtration Rate [eGFR] value <45 ml/min/1.73 m 2 ) during the 12 month pre-index period. Patients were classified as concordant or not concordant based on whether the first prescribed dose was consistent with label recommendations. Demographics, clinical characteristics, resource use and costs during pre-index were evaluated by DPP4-i concordance status. Of the 492 patients (323 sitagliptin, 57 saxagliptin, 112 linagliptin), 36.2% were prescribed doses that were not concordant with label recommendations (44.9% for sitagliptin, 57.9% for saxagliptin and 0% for linagliptin [which does not require dosage adjustment]). Concordant patients were slightly older (mean age 71 years vs. 68, p = .01) but had similar gender distribution (55% vs. 60% female, p = .31) compared to those who were not concordant. They had lower general health status (Charlson Comorbidity Score 2.6 vs. 2.2, p = .03), and had similar pre-index all-cause total costs ($25,245 vs. $21,972, p = .68) and lower pre-index T2DM-related costs ($1618 vs. $1922, p = .05). More than a third of DPP4-i patients with CKD stage 3b or higher were prescribed doses not concordant with DPP4-i label dosage recommendations.

Adherence to dipeptidyl peptidase-4 inhibitor therapy among type 2 diabetes patients with employer-sponsored health insurance in Japan.

PubMed

Kurtyka, Karen; Nishikino, Rie; Ito, Chie; Brodovicz, Kim; Chen, Yong; Tunceli, Kaan

2016-09-01

Dipeptidyl peptidase-4 inhibitors (DPP-4i) are a common first-line treatment for type 2 diabetes in Japan. However, little is known about patients' medication adherence, persistence and discontinuation in this setting. This was a retrospective cohort study of new DPP-4i users in a Japanese claims database. Adult patients (age 18-65 years) with type 2 diabetes diagnosis and no diagnosis of other diabetes or pregnancy during the study period were included if they were prescribed a DPP-4i as monotherapy or combination oral therapy. Adherence to therapy was measured using the proportion of days covered method over a fixed period of 1 year. The proportion of days covered of ≥80% was considered adherent. Persistence was defined as continuing index DPP-4i treatment with <90-day gap between refills. Patient baseline characteristics were explored as potential predictors of DPP-4i discontinuation and adherence in multivariable models. The final sample contained 2,874 monotherapy and 3,016 dual therapy patients. The mean age was approximately 51 years, and 75% were men. The mean proportion of days covered was 76.6% among monotherapy patients and 82.5% among dual therapy patients, with 67.2% of monotherapy and 74.4% of dual therapy patients classified as adherent. At 12 months, 72.2% of monotherapy and 79.2% of dual therapy patients were persistent. In adjusted models, younger age and having fewer concomitant medications were significantly associated with lower adherence and higher discontinuation, in both treatment groups. Those under the age of 45 years, and those with fewer concomitant medications were less likely to be adherent and persistent, and more likely to discontinue DPP-4i therapy. © 2016 Merck Sharp & Dohme Corp. Journal of Diabetes Investigation published by Asian Association of the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

Changes in Adenosine Deaminase Activity in Patients with Type 2 Diabetes Mellitus and Effect of DPP-4 Inhibitor Treatment on ADA Activity.

PubMed

Lee, Jae-Geun; Kang, Dong Gu; Yu, Jung Re; Kim, Youngree; Kim, Jinsoek; Koh, Gwanpyo; Lee, Daeho

2011-04-01

Dipeptidyl peptidase 4 (DPP-4, also known as CD26) binds with adenosine deaminase (ADA) to activate T lymphocytes. Here, we investigated whether ADA activity is specifically affected by treatment with DPP-4 inhibitor (DPP4I) compared with other anti-diabetic agents. Fasting ADA activity, in addition to various metabolic and biochemical parameters, were measured in 262 type 2 diabetes mellitus (T2DM) patients taking various anti-diabetic agents and in 46 non-diabetic control subjects. ADA activity was increased in T2DM patients compared with that in non-diabetic control subjects (mean±standard error, 23.1±0.6 U/L vs. 18.6±0.8 U/L; P<0.05). ADA activity was correlated with fasting plasma glucose (r=0.258, P<0.05), HbA1c (r=0.208, P<0.05), aspartate aminotransferase (r=0.325, P<0.05), and alanine aminotransferase (r=0.248, P<0.05). Compared with the well-controlled T2DM patients (HbA1c<7%), the poorly controlled group (HbA1c>9%) showed significantly increased ADA activity (21.1±0.8 U/L vs. 25.4±1.6 U/L; P<0.05). The effect of DPP4I on ADA activity in T2DM patients did not differ from those of other oral anti-diabetic agents or insulin. T2DM patients on metformin monotherapy showed a lower ADA activity (20.9±1.0 U/L vs. 28.1±2.8 U/L; P<0.05) compared with that of those on sulfonylurea monotherapy. Our results show that ADA activity is increased in T2DM patients compared to that in non-diabetic patients, is positively correlated with blood glucose level, and that DPP4I has no additional specific effect on ADA activity, except for a glycemic control- or HbA1c-dependent effect.

Effects of Health-Related Food Taxes and Subsidies on Mortality from Diet-Related Disease in New Zealand: An Econometric-Epidemiologic Modelling Study

PubMed Central

Ni Mhurchu, Cliona; Eyles, Helen; Genc, Murat; Scarborough, Peter; Rayner, Mike; Mizdrak, Anja; Nnoaham, Kelechi; Blakely, Tony

2015-01-01

Background Health-related food taxes and subsidies may promote healthier diets and reduce mortality. Our aim was to estimate the effects of health-related food taxes and subsidies on deaths prevented or postponed (DPP) in New Zealand. Methods A macrosimulation model based on household expenditure data, demand elasticities and population impact fractions for 18 diet-related diseases was used to estimate effects of five tax and subsidy regimens. We used price elasticity values for 24 major commonly consumed food groups in New Zealand, and food expenditure data from national Household Economic Surveys. Changes in mortality from cardiovascular disease, cancer, diabetes and other diet-related diseases were estimated. Findings A 20% subsidy on fruit and vegetables would result in 560 (95% uncertainty interval, 400 to 700) DPP each year (1.9% annual all-cause mortality). A 20% tax on major dietary sources of saturated fat would result in 1,500 (950 to 2,100) DPP (5.0%), and a 20% tax on major dietary sources of sodium would result in 2,000 (1300 to 2,700) DPP (6.8%). Combining taxes on saturated fat and sodium with a fruit and vegetable subsidy would result in 2,400 (1,800 to 3,000) DPP (8.1% mortality annually). A tax on major dietary sources of greenhouse gas emissions would generate 1,200 (750 to 1,700) DPP annually (4.0%). Effects were similar or greater for Maori and low-income households in relative terms. Conclusions Health-related food taxes and subsidies could improve diets and reduce mortality from diet-related disease in New Zealand. Our study adds to the growing evidence base suggesting food pricing policies should improve population health and reduce inequalities, but there is still much work to be done to improve estimation of health impacts. PMID:26154289

Evaluation of a Digital Behavioral Counseling Program for Reducing Risk Factors for Chronic Disease in a Workforce

PubMed Central

Wilson, Mark G.; Castro Sweet, Cynthia M.; Edge, Michael D.; Madero, Erica N.; McGuire, Megan; Pilsmaker, Megan; Carpenter, Dan; Kirschner, Scott

2017-01-01

Objective: To evaluate a digitally delivered, intensive behavioral counseling program for a workforce at risk for obesity-related chronic disease. Methods: Employees were offered a digital health program modeled after the diabetes prevention program (DPP). Annual workforce health assessments were used to examine changes in chronic disease risk factors between participants (n = 634) relative to a matched comparison group (n = 1268). Results: Overall, employees were gaining an average of 3.5 pounds annually before program inception. Program engagement was positive; 83% completed the majority of the curriculum and 31% lost at least 5% of their starting weight. Compared with non-participating peers, participants demonstrated reduced weight, improved fasting blood glucose, and improved nutritional intake after a year. Conclusions: The digital health program was effective for engaging employees in health behavior change. Digital options facilitate widespread implementation. PMID:28650899

Does Skin in the Game Matter if You Aren't Playing? Examining Participation in Oregon's Public Employee Health Engagement Model.

PubMed

Wright, Bill J; Dulacki, Kristen; Rissi, Jill; McBride, Leslie; Tran, Sarah; Royal, Natalie

2017-01-01

Employers are increasingly exploring health benefits that incentivize lifestyle change for employees. We used early data from an ongoing study of one such model-the Health Engagement Model (HEM), which Oregon implemented for all public employees in 2012-to analyze variation in employee participation and engagement. A survey was designed to assess program engagement, opinions of the program, and self-reported lifestyle changes. Data were collected in 2012, about 9 months after HEM launched. A representative random sample of 4500 state employees served as the study subjects. Primary measures included whether employees signed up for the program, completed its required activities, and reported making lifestyle changes. Logistic regression was used to analyze survey results. Most employees (86%) chose to participate, but there were important socioeconomic differences: some key target populations, including smokers and obese employees, were the least likely to sign up; less educated employees were also less likely to complete program activities. Despite mostly negative opinions of the program, almost half of participants reported making lifestyle changes. Oregon's HEM launch was largely unpopular with employees, but many reported making the desired lifestyle changes. However, some of those the program is most interested in enrolling were the least likely to engage. People involved with implementing similar programs will need to think carefully about how to cultivate broad interest among employees.

Catechol-O-methyltransferase association with hemoglobin A1c

PubMed Central

Hall, Kathryn T.; Jablonski, Kathleen A.; Chen, Ling; Harden, Maegan; Tolkin, Benjamin R.; Kaptchuk, Ted J.; Bray, George A.; Ridker, Paul M.; Florez, Jose C.; Chasman, Daniel I.

2016-01-01

Aims Catecholamines have metabolic effects on blood pressure, insulin sensitivity and blood glucose. Genetic variation in catechol-O-methyltransferase (COMT), an enzyme that degrades catecholamines, is associated with cardiometabolic risk factors and incident cardiovascular disease (CVD). Here we examined COMT effects on glycemic function and type 2 diabetes. Methods We tested whether COMT polymorphisms were associated with baseline HbA1c in the Women’s Genome Health Study (WGHS), and Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC), and with susceptibility to type 2 diabetes in WGHS, DIAbetes Genetics Replication And Meta-analysis consortium (DIAGRAM), and the Diabetes Prevention Program (DPP). Given evidence that COMT modifies some drug responses, we examined association with type 2 diabetes and randomized metformin and aspirin treatment. Results COMT rs4680 high-activity G-allele was associated with lower HbA1c in WGHS (β = −0.032% [0.012], p = 0.008) and borderline significant in MAGIC (β = −0.006% [0.003], p = 0.07). Combined COMT per val allele effects on type 2 diabetes were significant (OR = 0.98 [0.96–0.998], p = 0.03) in fixed-effects analyses across WGHS, DIAGRAM, and DPP. Similar results were obtained for 2 other COMT SNPs rs4818 and rs4633. In the DPP, the rs4680 val allele was borderline associated with lower diabetes incidence among participants randomized to metformin (HR = 0.81 [0.65–1.00], p = 0.05). Conclusions COMT rs4680 high-activity G-allele was associated with lower HbA1c and modest protection from type 2 diabetes. The directionality of COMT associations was concordant with those previously observed for cardiometabolic risk factors and CVD. PMID:27282867

30 CFR 250.269 - How will MMS evaluate the environmental impacts of the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... How will MMS evaluate the environmental impacts of the DPP or DOCD? The Regional Supervisor will... environmental documentation under the National Environmental Policy Act (NEPA) (42 U.S.C.4321 et seq.) and the... preparation of an EIS is required, the Regional Supervisor may require lessees and operators of leases or...

30 CFR 250.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 250.260 Section 250.260 Mineral Resources MINERALS MANAGEMENT... Operations Coordination Documents (docd) § 250.260 What Coastal Zone Management Act (CZMA) information must...

30 CFR 550.254 - What mitigation measures information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What mitigation measures information must accompany the DPP or DOCD? 550.254 Section 550.254 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and endangered species listed under the ESA; and (2) Marine mammals, as appropriate, if you have not...

30 CFR 550.254 - What mitigation measures information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What mitigation measures information must accompany the DPP or DOCD? 550.254 Section 550.254 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and endangered species listed under the ESA; and (2) Marine mammals, as appropriate, if you have not...

30 CFR 550.254 - What mitigation measures information must accompany the DPP or DOCD?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What mitigation measures information must accompany the DPP or DOCD? 550.254 Section 550.254 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and endangered species listed under the ESA; and (2) Marine mammals, as appropriate, if you have not...

30 CFR 250.249 - What air emissions information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... the DPP or DOCD? 250.249 Section 250.249 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... must list: (i) The projected peak hourly emissions; (ii) The total annual emissions in tons per year... frequency and duration of emissions; and (v) The total of all emissions listed in paragraph (a)(1)(i...

30 CFR 250.251 - If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Region, what planning information must accompany the DPP? 250.251 Section 250.251 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE... Development Operations Coordination Documents (docd) § 250.251 If I propose activities in the Alaska OCS...

30 CFR 250.256 - What related facilities and operations information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What related facilities and operations information must accompany the DPP or DOCD? 250.256 Section 250.256 Mineral Resources BUREAU OF OCEAN ENERGY... OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans...

30 CFR 250.250 - What oil and hazardous substance spills information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What oil and hazardous substance spills information must accompany the DPP or DOCD? 250.250 Section 250.250 Mineral Resources BUREAU OF OCEAN ENERGY... OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans...

30 CFR 550.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2013 CFR

2013-07-01

... Operations Coordination Documents (docd) § 550.260 What Coastal Zone Management Act (CZMA) information must... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 550.260 Section 550.260 Mineral Resources BUREAU OF OCEAN ENERGY...

30 CFR 550.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2014 CFR

2014-07-01

... Operations Coordination Documents (docd) § 550.260 What Coastal Zone Management Act (CZMA) information must... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 550.260 Section 550.260 Mineral Resources BUREAU OF OCEAN ENERGY...

30 CFR 250.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 250.260 Section 250.260 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR...