Comparison of plasma dipeptidyl peptidase IV activity in two caiman species: Caiman latirostris and Caiman yacare (Crocodylia, Alligatoridae)

2011 ◽  
Vol 61 (2) ◽  
pp. 199-210 ◽  
Author(s):  
María Parachú Marcó ◽  
Hugo Ortega ◽  
Mark Merchant ◽  
Pablo Siroski ◽  
Gisela Poletta
Keyword(s):  
Significant Positive Correlation ◽  
Bioactive Peptides ◽  
Plasma Concentrations ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Time Dependent ◽  
Strong Positive Correlation ◽  
Positive Correlation ◽  
Susceptibility To Infection ◽  
Physiological Regulator

AbstractDipeptidyl peptidase IV (DPPIV) is a well-characterized protease with broad substrate specificity, functionally-related to the activity of many bioactive peptides. It plays an important role as physiological regulator of a number of peptides that serve as biochemical messengers within the immune system. Plasma DPPIV activity was characterized with respect to temperature, kinetics and concentration dependence in two species of caiman, the broad-snouted caiman (Caiman latirostris) and the black yacare (Caiman yacare). DPPIV activity showed a significant positive correlation from titrations carried out in the presence of different plasma concentrations. DPPIV activity was lower in C. yacare than in C. latirostris at all temperatures tested. C. yacare DPPIV activity showed a significant increase only at higher temperatures whilst C. latirostris plasma demonstrated a strong positive correlation starting at the lowest temperature, probably due to an adaptation for the tolerance of lower temperatures. Exposure of C. latirostris and C. yacare plasma at different time points showed that plasma DPPIV activities were time-dependent, and that the titer-dependent curves were different for the two species. These results revealed that plasma DPPIV activities were different between these two crocodilian species, which could contribute to the differences in susceptibility to infection between them.

scholarly journals Preservation of active incretin hormones by inhibition of dipeptidyl peptidase IV suppresses meal-induced incretin secretion in dogs

2002 ◽  
Vol 172 (2) ◽  
pp. 355-362 ◽  
Author(s):  
CF Deacon ◽  
S Wamberg ◽  
P Bie ◽  
TE Hughes ◽  
JJ Holst
Keyword(s):  
Plasma Concentrations ◽  
Dipeptidyl Peptidase ◽  
Feedback Mechanism ◽  
Dipeptidyl Peptidase Iv ◽  
Biologically Active ◽  
Incretin Hormones ◽  
Dpp Iv ◽  
Incretin Secretion ◽  
Glucagon Like Peptide 1

The incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are degraded by dipeptidyl peptidase IV (DPP IV), thereby losing insulinotropic activity. DPP IV inhibition reduces exogenous GLP-1 degradation, but the extent of endogenous incretin protection has not been fully assessed, largely because suitable assays which distinguish between intact and degraded peptides have been unavailable. Using newly developed assays for intact GLP-1 and GIP, the effect of DPP IV inhibition on incretin hormone metabolism was examined. Conscious dogs were given NVP-DPP728, a specific DPP IV inhibitor, at a dose that inhibited over 90% of plasma DPP IV for the first 90 min following treatment. Total and intact incretin concentrations increased (P<0.0001) following a mixed meal, but on control days (vehicle infusion), intact peptide concentrations were lower (P<0.01) than total peptide concentrations (22.6 +/- 1.2% intact GIP; 10.1 +/- 0.4% intact GLP-1). Following inhibitor treatment, the proportion of intact peptide increased (92.5 +/- 4.3% intact GIP, P<0.0001; 99.0 +/- 22.6% intact GLP-1, P<0.02). Active (intact) incretins increased after NVP-DPP728 (from 4797 +/- 364 to 10 649 +/- 106 pM x min for GIP, P<0.03; from 646 +/- 134 to 2822 +/- 528 pM x m in for GLP-1, P<0.05). In contrast, total incretins fell (from 21 632 +/- 654 to 12 084 +/- 1723 pM x min for GIP, P<0.002; from 5145 +/- 677 to 3060 +/- 601 pM x min for GLP-1, P<0.05). Plasma glucose, insulin and glucagon concentrations were unaltered by the inhibitor. We have concluded that DPP IV inhibition with NVP-DPP728 prevents N-terminal degradation of endogenous incretins in vivo, resulting in increased plasma concentrations of intact, biologically active GIP and GLP-1. Total incretin secretion was reduced by DPP IV inhibition, suggesting the possibility of a feedback mechanism.

scholarly journals Effect of Micronutrients on Thyroid Parameters

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Hari Krishnan Krishnamurthy ◽  
Swarnkumar Reddy ◽  
Vasanth Jayaraman ◽  
Karthik Krishna ◽  
Qi Song ◽  
...  
Keyword(s):  
Amino Acids ◽  
Significant Positive Correlation ◽  
Clinical Laboratory ◽  
Serum Levels ◽  
Strong Positive Correlation ◽  
Healthy Individuals ◽  
Hormone Metabolism ◽  
Positive Correlation ◽  
Thyroid Hormone Metabolism ◽  
Iron And Zinc

Micronutrients are involved in various vital cellular metabolic processes including thyroid hormone metabolism. This study aimed to investigate the correlation between serum levels of micronutrients and their effects on thyroid parameters. The correlation of serum levels of micronutrients and thyroid markers was studied in a group of 387 healthy individuals tested for thyroid markers (T4, T3, FT4, FT3, TSH, anti-TPO, RT3, and anti-Tg) and their micronutrient profile at Vibrant America Clinical Laboratory. The subjects were rationalized into three groups (deficient, normal, or excess levels of micronutrients), and the levels of their thyroid markers were compared. According to our results, deficiency of vitamin B2, B12, and B9 and Vit-D25[OH] ( p < 0.05 ) significantly affected thyroid functioning. Other elemental micronutrients such as calcium, copper, choline, iron, and zinc ( p < 0.05 ) have a significant correlation with serum levels of free T3. Amino acids asparagine (r = 0.1765, p < 0.001 ) and serine (r = 0.1186, p < 0.05 ) were found to have a strong positive correlation with TSH. Valine, leucine, and arginine ( p < 0.05 ) also exhibited a significant positive correlation with serum levels of T4 and FT4. No other significant correlations were observed with other micronutrients. Our study suggests strong evidence for the association of the levels of micronutrients with thyroid markers with a special note on the effect of serum levels of certain amino acids.

scholarly journals Investigation of Breast Cancer Microstructure and Microvasculature from Time-Dependent DWI and CEST in Correlation with Histological Biomarkers

2021 ◽  
Author(s):  
Yuko Someya ◽  
Mami Iima ◽  
Hirohiko Imai ◽  
Akihiko Yoshizawa ◽  
Masako Kataoka ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Xenograft Model ◽  
Time Dependent ◽  
Amide Proton ◽  
Strong Positive Correlation ◽  
Ki 67 ◽  
B Values ◽  
Positive Correlation ◽  
Non Gaussian ◽  
Mcf 7

Abstract We investigated the associations of time-dependent DWI, non-Gaussian DWI and CEST parameters with histological biomarkers in a breast cancer xenograft model. 22 xenograft mice (7 MCF-7 and 15 MDA-MB-231) were scanned at 2 diffusion times (Td= 2.5/ 5 ms) with 11 b values (0–600 s/mm2), and 9/ 27.6 ms with 17 b values (0–3000 s/mm2). The apparent diffusion coefficient, ADC0 − 600, shifted ADC, sADC200 − 1500 and the ADC change with Td, as well as IVIM and non-Gaussian diffusion parameters were estimated. CEST images were acquired and the amide proton transfer signal intensity (APT SI) were measured. The sADC200 − 1500 change and combined ADC change (ADC0 − 600, 2.5 ms with sADC200 − 1500, 27.6 ms) was significantly larger for MCF-7 group, and the combined ADC change was positively correlated with Ki67max and APT SI. ADC0 decreased significantly in MDA-MB-231 group and K increased significantly with Td in MCF-7 group. APT SI and cellular area had a moderately strong positive correlation in MDA-MB-231 and MCF-7 tumors combined, and there was a positive correlation in MDA-MB-231 tumors. There was a significant negative correlation between APT SI and the Ki-67-positive ratio in MDA-MB-231 tumors and when combined with MCF-7 tumors. The associations of combined ADC change and API SI with Ki-67 parameters indicate that the Td-dependent DW and CEST parameters are useful to predict the histological markers of breast cancers.

scholarly journals Autumn and winter kidney fat indexes of roe deer does and their correlation with reproductive parameters

2013 ◽  
pp. 61-65
Author(s):  
István Majzinger
Keyword(s):  
Significant Positive Correlation ◽  
Roe Deer ◽  
Recruitment Rate ◽  
Corpora Lutea ◽  
Strong Positive Correlation ◽  
Reproductive Parameters ◽  
Game Management ◽  
Positive Correlation ◽  
Kidney Fat ◽  
Autumn And Winter

I studied the variations of kidney fat indexes (KFI) in two game management units of the Great Hungarian Plain between 2002 and 2004 in the autumn and winter months. I was looking for correlation between the autumn and winter KFI as well as between the autumn KFI and reproductive parameters (number of corpora lutea, recruitment rate). There was a significant positive correlation between the average winter and the average next autumn KFI (r=0.991, p<0.1). The average winter KFI showed strong positive correlation with the average number of corpora lutea (CL) in the next rutting season (r=0.978, p<0.05). The average autumn KFI and the average grown up offspring showed positive but not significant correlation (r=0.725, p=0.275).

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