Partial protection against streptozotocin-induced hyperglycaemia by superoxide dismutase linked to polyethylene glycol

1984 ◽  
Vol 107 (3) ◽  
pp. 390-394 ◽  
Author(s):  
kjell Asplund ◽  
Kjell Grankvist ◽  
Stefan Marklund ◽  
Inge-Bert Täljedal
Keyword(s):  
Superoxide Dismutase ◽  
Polyethylene Glycol ◽  
Blood Glucose ◽  
Superoxide Radicals ◽  
High Dose ◽  
Partial Protection ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Pre Treatment

Abstract. To test the possible role of superoxide radicals in the diabetogenic action of streptozotocin, blood glucose levels were measured in mice after a single high-dose (150 mg/kg body weight) or multiple low-dose (40 mg/kg for 5 days) injections of streptozotocin. Pre-treatment 6 h before streptozotocin with 250–300 mg/kg superoxide dismutase coupled to polyethylene glycol reduced the hyperglycaemic response in mice injected with a single dose of streptozotocin. The blood glucose levels after multiple low doses of streptozotocin were not affected by superoxide dismutase-polvethvlene glycol. Enzymatically inactive superoxide dismutase did not affect the development of hyperglycaemia. The results suggest that superoxide radicals may play a role in the diabetogenic action of streptozotocin injected as a high-dose single bolus.

The Role of Biomaterials in Insulin Delivery Systems

1980 ◽  
Vol 3 (5) ◽  
pp. 299-304 ◽  
Author(s):  
S.D. Bruck
Keyword(s):  
Blood Glucose ◽  
Glucose Sensor ◽  
Insulin Delivery ◽  
The United States ◽  
Delivery Systems ◽  
Open Loop ◽  
Health Concern ◽  
Glucose Levels ◽  
Blood Glucose Levels

The control of blood glucose levels in diabetes involving devices are critically reviewed, and the role of blood-contacting biomaterial components analyzed. These include mechanical insulin-delivery systems of the closed-loop type that require an electronic glucose sensor and feedback, and open-loop systems that deliver insulin without a sensor and feedback. Whole pancreatic and islet transplantations, islet encapsulation, and the potential role of polymeric sustained drug delivery systems are discussed. The medical and social impacts of diabetes mellitus are of prime public health concern and of even greater magnitude than those of heart disease in the United States. While future advances in device design, miniaturization, and biometrials technology will significantly add to the arsenal of therapeutic alternatives, devices capable of controlling blood glucose levels ought to be viewed as mere interim phases rather than as final goals of the problem.

Liver glycogen content decreases during meals in rats

1982 ◽  
Vol 243 (3) ◽  
pp. R450-R453
Author(s):  
W. Langhans ◽  
N. Geary ◽  
E. Scharrer
Keyword(s):  
Blood Glucose ◽  
Glycogen Content ◽  
Liver Glycogen ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Liver Glycogen Content ◽  
Ad Libitum ◽  
Portal Veins ◽  
Hepatic Portal

The effects of feeding on liver glycogen content and blood glucose in the hepatic and hepatic portal veins were investigated in rats. Liver glycogen content decreased about 25% during meals both in rats refed after 12 h food deprivation (23 +/- 1 to 17 +/- 1 mg glycogen/g liver) and in ad libitum-fed rats taking fully spontaneous meals (44 +/- 2 to 32 +/- 2 mg/g). Liver glycogen began to increase within 30 min after meals in ad libitum-fed rats. Hepatic vein blood glucose levels at meal onset (118 +/- 4 mg/dl in the food-deprived rats, 127 +/- 4 in ad libitum-fed rats) and at meal end (155 +/- 3 and 166 +/- 5 mg/dl, respectively) were similar in the two groups. Portal vein blood glucose increased during meals in the previously food-deprived rats (83 +/- 4 to 116 +/- 6 mg/dl) but not in the ad libitum-fed rats (127 +/- 5 to 132 +/- 3 mg/dl). Mechanisms that may elicit prandial glycogenolysis and the possible role of this effect in the production of meal ending satiety are discussed.

Capsaicin-sensitive nerves are required for glucostasis but not for catecholamine output during hypoglycemia in rats

1990 ◽  
Vol 258 (1) ◽  
pp. E212-E219 ◽  
Author(s):  
X. F. Zhou ◽  
K. H. Jhamandas ◽  
B. G. Livett
Keyword(s):  
Blood Glucose ◽  
Somatostatin Analogue ◽  
Plasma Epinephrine ◽  
Conscious Rat ◽  
Glucose Response ◽  
Conscious Rats ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Sensory Fibers

We have studied the glucose response and catecholamine (CA) response to insulin in the conscious rat to evaluate the role of sensory fibers in these responses in animals pretreated with capsaicin as neonates. In contrast to previous results obtained in anesthetized rats (Z. Khalil, B.G. Livett, and P.D. Marley. J. Physiol. Lond. 370: 201-215, 1986; Z. Khalil, B.G. Livett, and P.D. Marley. J. Physiol. Lond. 391: 511-526, 1987.), in conscious rats, insulin (1 IU/kg iv) produced only a mild hypoglycemia, which quickly returned to resting levels and caused no significant changes in plasma epinephrine levels. Somatostatin and SMS-(201-995), a somatostatin analogue, both potentiated and prolonged the insulin-induced hypoglycemia, resulting in an increase in circulating CA levels that was suppressed by hexamethonium and atropine. In capsaicin-pretreated rats the blood glucose levels at 90 min after insulin were significantly lower than those in vehicle-pretreated rats both in the presence (1 IU/kg insulin, 48 +/- 6 vs. 92 +/- 6 mg/100 ml, P less than 0.01) and absence (10 IU/kg insulin, 38 +/- 4 vs. 51 +/- 2 mg/100 ml, P less than 0.01) of SMS-(201-995). The CA levels in capsaicin-pretreated rats at 90 min after insulin were higher than in vehicle-pretreated rats (epinephrine levels: 27 +/- 4 vs. 10 +/- 1 pmol/ml in 1 IU/kg insulin, P less than 0.01; 64 +/- 14 vs. 25 +/- 5 pmol/ml in 10 IU/kg insulin, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Role of PPAR in Hepatic Carbohydrate Metabolism

PPAR Research ◽  
2010 ◽  
Vol 2010 ◽  
pp. 1-12 ◽  
Author(s):  
Annelies Peeters ◽  
Myriam Baes
Keyword(s):  
Lipid Metabolism ◽  
Blood Glucose ◽  
Carbohydrate Metabolism ◽  
Glucose Homeostasis ◽  
Tight Control ◽  
Master Regulator ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Ppar Ligands

Tight control of storage and synthesis of glucose during nutritional transitions is essential to maintain blood glucose levels, a process in which the liver has a central role. PPAR is the master regulator of lipid metabolism during fasting, but evidence is emerging for a role of PPAR in balancing glucose homeostasis as well. By using PPAR ligands and PPAR mice, several crucial genes were shown to be regulated by PPAR in a direct or indirect way. We here review recent evidence that PPAR contributes to the adaptation of hepatic carbohydrate metabolism during the fed-to-fasted or fasted-to-fed transition in rodents.

scholarly journals Oreocnide integrifoliaFlavonoids Augment Reprogramming for Islet Neogenesis andβ-Cell Regeneration in Pancreatectomized BALB/c Mice

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Ansarullah ◽  
Bhavna Bharucha ◽  
Malati Umarani ◽  
Mitesh Dwivedi ◽  
Naresh C. Laddha ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Blood Glucose ◽  
Brdu Incorporation ◽  
Cell Regeneration ◽  
Mice Model ◽  
Islet Neogenesis ◽  
Glucose Levels ◽  
Ductal Cells ◽  
Blood Glucose Levels

Agents which can either trigger proliferation ofβ-cells or induce neogenesis ofβ-cells from precursors would be of pivotal role in reversing diabetic manifestations. We examined the role of flavonoid rich fraction (FRF) ofOreocnide integrifolialeaves using a mice model of experimental regeneration. BALB/c mice were subjected to ~70% pancreatectomy (Px) and supplemented with FRF for 7, 14, and 21 days after pancreatectomy. Px animals displayed increased blood glucose levels and decreased insulin titres which were ameliorated by FRF supplementation. FRF-treated mice demonstrated prominent newly formed islets budding off from ducts and depicting increased BrdU incorporation. Additionally, transcripts levels of Ins1/2, Reg-3α/γ, Ngn-3, and Pdx-1 were upregulated during the initial 1 week. The present study provides evidence of a nutraceutical contributing to islet neogenesis from ductal cells as the mode ofβ-cell regeneration and a potential therapeutic for clinical trials in management of diabetic manifestations.

Streptozotocin-induced diabetes differentially affects sympathetic innervation and control of plantar metatarsal and mesenteric arteries in the rat

2013 ◽  
Vol 304 (2) ◽  
pp. H215-H228 ◽  
Author(s):  
Niloufer J. Johansen ◽  
Diana Tripovic ◽  
James A. Brock
Keyword(s):  
Blood Glucose ◽  
Vascular Function ◽  
Neural Control ◽  
Sympathetic Innervation ◽  
Nerve Fibers ◽  
Transmural Pressure ◽  
Mesenteric Arteries ◽  
High Dose ◽  
Glucose Levels ◽  
Blood Glucose Levels

In humans neural control of arterial vessels supplying skin in the extremities is particularly vulnerable to the effects of diabetes. Here the streptozotocin (STZ) rat model of type 1 diabetes was used to compare effects on neurovascular function in plantar metatarsal arteries (PMAs), which supply blood to skin of hind paw digits, with those in mesenteric arteries (MAs). Twelve weeks after STZ (60 mg/kg ip), wire myography was used to assess vascular function. In PMAs, lumen dimensions were unchanged but both nerve-evoked contractions and sensitivity to α1 (phenylephrine, methoxamine)- and α2 (clonidine)-adrenoceptor agonists were reduced. The density of perivascular nerve fibers was also reduced by ∼25%. These changes were not observed in PMAs from STZ-treated rats receiving either a low dose of insulin that did not greatly reduce blood glucose levels or a high dose of insulin that markedly reduced blood glucose levels. In MAs from STZ-treated rats, nerve-evoked increases in force did not differ from control but, because lumen dimensions were ∼20% larger, nerve-evoked increases in effective transmural pressure were smaller. Increases in effective transmural pressure produced by phenylephrine or α,β-methylene ATP in MAs from STZ-treated rats were not smaller than control, but the density of perivascular nerve fibers was reduced by ∼10%. In MAs, the increase in vascular dimensions is primarily responsible for reducing effectiveness of nerve-evoked constrictions. By contrast, in PMAs decreases in both the density of perivascular nerve fibers and the reactivity of the vascular muscle appear to explain impairment of neurovascular transmission.

scholarly journals A Machine-Generated View of the Role of Blood Glucose Levels in the Severity of COVID-19

2021 ◽  
Vol 9 ◽  
Author(s):  
Emmanuelle Logette ◽  
Charlotte Lorin ◽  
Cyrille Favreau ◽  
Eugenia Oshurko ◽  
Jay S. Coggan ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Glucose Levels ◽  
Blood Glucose Levels

Graphical Abstract

scholarly journals Evaluation of the oxidative profile of critical patients hospitalized in adult intensive care unit

2021 ◽  
Vol 43 ◽  
pp. e13-43351
Author(s):  
Lídia Miranda Brinati ◽  
Carla De Fátima Januário ◽  
Silvia Almeida Cardoso ◽  
Tiago Ricardo Moreira ◽  
Daniel Silva Sena Bastos ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Lipid Peroxidation ◽  
Superoxide Dismutase ◽  
Intensive Care ◽  
Blood Glucose ◽  
Initial Time ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Reducing Ability ◽  
Critical Patients

The objective of this work was to evaluate and correlate the oxidative stress in patients with uncontrolled blood glucose levels (hyperglycemia or hypoglycemia) hospitalized in an intensive care unit (ICU). This was a cross-sectional study, performed with 26 patients in an ICU of a hospital in the Zona da Mata in Minas Gerais. Patients with uncontrolled blood glucose levels were evaluated in two moments: on the day of admission (T0) and one day after the uncontrolled glycaemia (DG1). The evaluation of the oxidative profile was determined by the dosage of serum total antioxidant capacity, based on the ability of ferric reduction, determination of enzymatic activity of Superoxide Dismutase, Catalase and Glutathione S-Transferase, lipid peroxidation products and carbonylated proteins. The levels of ferric reducing ability decreased significantly, whereas the activity of the Superoxide Dismutase enzyme increased significantly after uncontrolled glycaemia in relation to the initial time. Although the lipid peroxidation did not change between the times evaluated, the damage marker significantly reduced, shown by carbonylation of proteins after the uncontrolled glycaemia. The critical patients evaluated in this study present altered oxidative profile after the uncontrolled glycaemia, a common problem that imposes the worst prognoses.

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