Comparison of mandibular trabecular structures between normal and diabetic rats: evaluation of spontaneous type 2 diabetes in a rat model

2011 ◽  
Vol 27 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Kazuo Onoyama ◽  
Ryota Kawamata ◽  
Yusuke Kozai ◽  
Takashi Sakurai ◽  
Isamu Kashima
Keyword(s):  
Type 2 Diabetes ◽  
Rat Model ◽  
Diabetic Rats

scholarly journals Role of TLR4/MyD88/NF-κB signaling in heart and liver-related complications in a rat model of type 2 diabetes mellitus

2021 ◽  
Vol 49 (3) ◽  
pp. 030006052199759
Author(s):  
Jiajia Tian ◽  
Yanyan Zhao ◽  
Lingling Wang ◽  
Lin Li
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Signaling Pathway ◽  
Rat Model ◽  
Fasting Blood Glucose ◽  
Diabetic Rats ◽  
Primary Response ◽  
Monocyte Chemoattractant Protein 1

Aims To analyze expression of members of the Toll-like receptor (TLR)4/myeloid differentiation primary response 88 (MyD88)/nuclear factor (NF)-κB signaling pathway in the heart and liver in a rat model of type 2 diabetes mellitus (T2DM). Our overall goal was to understand the underlying pathophysiological mechanisms. Methods We measured fasting blood glucose (FBG) and insulin (FINS) in a rat model of T2DM. Expression of members of the TLR4/MyD88/NF-κB signaling pathway as well as downstream cytokines was investigated. Levels of mRNA and protein were assessed using quantitative real-time polymerase chain reaction and western blotting, respectively. Protein content of tissue homogenates was assessed using enzyme-linked immunosorbent assays. Results Diabetic rats had lower body weights, higher FBG, higher FINS, and higher intraperitoneal glucose tolerance than normal rats. In addition, biochemical indicators related to heart and liver function were elevated in diabetic rats compared with normal rats. TLR4 and MyD88 were involved in the occurrence of T2DM as well as T2DM-related heart and liver complications. TLR4 caused T2DM-related heart and liver complications through activation of NF-κB. Conclusions TLR4/MyD88/NF-κB signaling induces production of tumor necrosis factor-α, interleukin-6, and monocyte chemoattractant protein-1, leading to the heart- and liver-related complications of T2DM.

scholarly journals The Biological Impacts of Sitagliptin on the Pancreas of a Rat Model of Type 2 Diabetes Mellitus: Drug Interactions with Metformin

Biology ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 6 ◽  
Author(s):  
Lamiaa M. Shawky ◽  
Ahmed A. Morsi ◽  
Eman El Bana ◽  
Safaa Masoud Hanafy
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Rat Model ◽  
Cell Damage ◽  
Diabetic Rats ◽  
Male Rats ◽  
Control Group ◽  
Dipeptidyl Peptidase 4

Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is a beneficial class of antidiabetic drugs. However, a major debate about the risk of developing pancreatitis is still existing. The aim of the work was to study the histological and immunohistochemical effects of sitagliptin on both endocrine and exocrine pancreases in a rat model of type 2 diabetes mellitus and to correlate these effects with the biochemical findings. Moreover, a possible synergistic effect of sitagliptin, in combination with metformin, was also evaluated. Fifty adult male rats were used and assigned into five equal groups. Group 1 served as control. Group 2 comprised of untreated diabetic rats. Group 3 diabetic rats received sitagliptin. Group 4 diabetic rats received metformin. Group 5 diabetic rats received both combined. Treatments were given for 4 weeks after the induction of diabetes. Blood samples were collected for biochemical assay before the sacrification of rats. Pancreases were removed, weighed, and were processed for histological and immunohistochemical examination. In the untreated diabetic group, the islets appeared shrunken with disturbed architecture and abnormal immunohistochemical reactions for insulin, caspase-3, and inducible nitric oxide synthase (iNOS). The biochemical findings were also disturbed. Morphometrically, there was a significant decrease in the islet size and islet number. Treatment with sitagliptin, metformin, and their combination showed an improvement, with the best response in the combined approach. No evidence of pancreatic injury was identified in the sitagliptin-treated groups. In conclusion, sitagliptin had a cytoprotective effect on beta-cell damage. Furthermore, the data didn’t indicate any detrimental effects of sitagliptin on the exocrine pancreas.

scholarly journals P0978THE EFFECTS OF CHRONIC DAPAGLIFLOZIN TREATMENT ON THE RENAL MICROVASCULATURE IN A RAT MODEL OF TYPE 2 DIABETES

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Connie Ow ◽  
Vijayakumar Sukumaran ◽  
Jennifer Ngo ◽  
Cheng Kun Du ◽  
Akihiro Fujiwara ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Type 2 Diabetes ◽  
Diabetic Nephropathy ◽  
Endothelial Dysfunction ◽  
Rat Model ◽  
Renal Injury ◽  
Diabetic Rats ◽  
Renal Microvasculature ◽  
Vasodilatory Function

Abstract Background and Aims Chronic kidney disease (CKD) is an ever-growing concern and CKD associated with diabetes accounted for ∼ 35% of new cases of end-stage renal failure. Clinical trials with insulin-independent sodium-glucose co-transporter 2 (SGLT2) inhibitors not only showed significant improvements in hyperglycemia and thus renal damage, but also reduced the risk of adverse cardiovascular events. Microvessels supply local tissue oxygen demands and are important controllers of regional perfusion. Endothelial dysfunction has been posited to be an important factor driving the pathogenesis of diabetic nephropathy, largely through impaired eNOS activity and thus reduced nitric oxide bioavailability. Thus, we aim to determine the effects of SGLT2 inhibition on vasodilator function in the renal vasculature. We hypothesize that rats chronically treated with dapagliflozin, a SGLT2 inhibitor, improves renal endothelial function and the microvessels are better able to maintain perfusion in response to the inhibition of nitric oxide synthase and prostaglandin blockade. Method Male Zucker fatty diabetic rats (8 wk old), a model of type 2 diabetes, were given daily oral gavage of 1 mg/kg dapagliflozin or its vehicle for up to 22 wks of age (n=6/group). Renal excretory function, glomerular filtration rate (GFR) and indices of renal injury was assessed before treatment and after every 4 wks up until 22 wks of age. GFR was assessed via transcutaneous clearance of FITC-sinistrin. Vasodilator function of the renal microvasculature was assessed via X-ray microangiography. We conducted successive imaging of the microvessels before and during infusion of acetylcholine (ACh) and sodium nitroprusside (SNP) which facilitated the assessment of endothelium dependent and independent dilation respectively. After which, rats were given successive boluses of L-NAME and indomethacin to assess the vasodilatory function of the microvasculature independent of nitric oxide and prostaglandins respectively. These inhibitors were given under the conditions of SNP clamp which allowed for us to titrate the blood pressure to baseline levels. Lastly, we assessed the ability of endothelium hyperpolarizing factors (EDHFs) to maintain microvascular perfusion when SNP infusion ceased and an infusion of ACh commenced while still under the effects of L-NAME and indomethacin. Results As expected, dapagliflozin alleviated hyperglycemia across the treatment period. There was a tendency for dapagliflozin to ameliorate the decline of GFR, although this apparent effect was not statistically significant. Dapagliflozin did not appear to improve indices of renal injury. Treatment with dapagliflozin alleviated polyuria but did not appear to have an impact on urine osmolarity or sodium excretion. The responses (vessel diameter) of renal microvessels to ACh and SNP was greater in dapagliflozin than in vehicle fed rats. The microvessels of vehicle fed rats appeared to undergo relative constriction in response to L-NAME and indomethacin even under the effects of SNP clamp. In contrast, microvessels of dapagliflozin fed rats appeared to be relatively well-perfused after NOS and COX blockade. This suggests that dapagliflozin may improve endothelial dysfunction commonly associated with diabetic nephropathy. Following NOS and COX blockade, ACh was infused in rats to determine the status of vasodilatory function mediated by EDHFs. The microvessels in diabetic rats did not appear to be dilated after infusion of ACh, suggesting that vasodilatory effects of EDHFs on the vasculature is diminished in diabetic rats. Dapagliflozin appeared to improve this effect in that the renal microvessels were dilated even when NOS and COX production was blocked/inhibited. Conclusion Chronic treatment of dapagliflozin may improve endothelial dysfunction and thus retard the progression of diabetic nephropathy in a rat model of type 2 diabetes.

Delayed bone regeneration and low bone mass in a rat model of insulin-resistant type 2 diabetes mellitus is due to impaired osteoblast function

2011 ◽  
Vol 301 (6) ◽  
pp. E1220-E1228 ◽  
Author(s):  
Christine Hamann ◽  
Claudia Goettsch ◽  
Jan Mettelsiefen ◽  
Veit Henkenjohann ◽  
Martina Rauner ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Bone Regeneration ◽  
Rat Model ◽  
Diabetic Rats ◽  
Low Bone Mass ◽  
Insulin Resistant ◽  
Zdf Rats

Patients with diabetes mellitus have an impaired bone metabolism; however, the underlying mechanisms are poorly understood. Here, we analyzed the impact of type 2 diabetes mellitus on bone physiology and regeneration using Zucker diabetic fatty (ZDF) rats, an established rat model of insulin-resistant type 2 diabetes mellitus. ZDF rats develop diabetes with vascular complications when fed a Western diet. In 21-wk-old diabetic rats, bone mineral density (BMD) was 22.5% (total) and 54.6% (trabecular) lower at the distal femur and 17.2% (total) and 20.4% (trabecular) lower at the lumbar spine, respectively, compared with nondiabetic animals. BMD distribution measured by backscattered electron imaging postmortem was not different between diabetic and nondiabetic rats, but evaluation of histomorphometric indexes revealed lower mineralized bone volume/tissue volume, trabecular thickness, and trabecular number. Osteoblast differentiation of diabetic rats was impaired based on lower alkaline phosphatase activity (−20%) and mineralized matrix formation (−55%). In addition, the expression of the osteoblast-specific genes bone morphogenetic protein-2, RUNX2, osteocalcin, and osteopontin was reduced by 40–80%. Osteoclast biology was not affected based on tartrate-resistant acidic phosphatase staining, pit formation assay, and gene profiling. To validate the implications of these molecular and cellular findings in a clinically relevant model, a subcritical bone defect of 3 mm was created at the left femur after stabilization with a four-hole plate, and bone regeneration was monitored by X-ray and microcomputed tomography analyses over 12 wk. While nondiabetic rats filled the defects by 57%, diabetic rats showed delayed bone regeneration with only 21% defect filling. In conclusion, we identified suppressed osteoblastogenesis as a cause and mechanism for low bone mass and impaired bone regeneration in a rat model of type 2 diabetes mellitus.

scholarly journals The Hepatoprotective Effect of Jaboticaba Peel Powder in a Rat Model of Type 2 Diabetes Mellitus Involves the Modulation of Thiol/Disulfide Redox State through the Upregulation of Glutathione Synthesis

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Andréia Quatrin ◽  
Lisiane Conte ◽  
Dariane Trivisiol da Silva ◽  
Cassieli Gehlen Figueiredo ◽  
Sabrina Somacal ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Rat Model ◽  
Antioxidant Properties ◽  
Redox Balance ◽  
Diabetic Rats ◽  
Hepatic Damage ◽  
Glutathione Synthesis

Jaboticaba peel powder (JPP) is rich in bioactive compounds, mainly soluble and insoluble polyphenols with great antioxidant properties. The aim of this study is to evaluate the effects of JPP supplementation on the oxidative stress and hepatic damage in a rat model of type 2 diabetes mellitus (T2DM). Diabetic rats received vehicle or JPP at 2.7 (JPP-I), 5.4 (JPP-II), or 10.8 (JPP-III) g/L in drinking water during 8 weeks. JPP-III attenuated hyperglycaemia and dyslipidemia increased by 86% the liver content of nonprotein thiol groups and by 90% the GSH/GSSG ratio by activating glutathione synthesis. Accordingly, JPP supplementation prevented the loss of activity of the sulfhydryl-dependent enzymeδ-aminolaevulinic acid dehydratase and attenuated hepatic injury assessed by the reduction of serum aspartate aminotransferase activity and liver hypertrophy. Our results support that JPP supplementation to T2DM rats decreases hepatic damage most likely by increasing glutathione synthesis and modulating the thiol/disulfide redox balance.

scholarly journals Uninephrectomized High-Fat-Fed Nicotinamide-Streptozotocin-Induced Diabetic Rats: A Model for the Investigation of Diabetic Nephropathy in Type 2 Diabetes

2016 ◽  
Vol 2016 ◽  
pp. 1-18 ◽  
Author(s):  
Valentina K. Bayrasheva ◽  
Alina Yu. Babenko ◽  
Vladimir A. Dobronravov ◽  
Yuri V. Dmitriev ◽  
Svetlana G. Chefu ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Rat Model ◽  
Diabetic Rats ◽  
Metabolic Parameters ◽  
Tubular Injury ◽  
High Fat ◽  
Alimentary Obesity ◽  
Normal Chow ◽  
Male Wistar Rats

Type 2 diabetes (DM2) could be reproduced in rats with alimentary obesity by using low doses of streptozotocin (LD-STZ) as well as STZ in high doses with preliminary nicotinamide (NA) administration. However, STZ could induce tubulotoxicity.Aim. To develop rat model of DN in NA-STZ-induced DM2 and compare it with LD-STZ-model in order to choose the most relevant approach for reproducing renal glomerular and tubular morphofunctional diabetic changes. Starting at 3 weeks after uninephrectomy, adult male Wistar rats were fed five-week high-fat diet and then received intraperitoneally either LD-STZ (40 mg/kg) or NA (230 mg/kg) followed by STZ (65 mg/kg). Control uninephrectomized vehicle-injected rats received normal chow. At weeks 10, 20, and 30 (the end of the study), metabolic parameters, creatinine clearance, albuminuria, and urinary tubular injury markers (NGAL, KIM-1) were evaluated as well as renal ultrastructural and light microscopic changes at weeks 20 and 30. NA-STZ-group showed higher reproducibility and stability of metabolic parameters. By week 10, in NA-STZ-group NGAL level was significantly lower compared to LD-STZ-group. By week 30, diabetic groups showed early features of DN. However, morphofunctional changes in NA-STZ-group appeared to be more pronounced than those in STZ-group despite lower levels of KIM-1 and NGAL. We proposed a new rat model of DM2 with DN characterized by stable metabolic disorders, typical renal lesions, and lower levels of tubular injury markers as compared to LD-STZ-induced diabetes.

1045: Pioglitazone Ameliorates Penile Corpora Veno-Occlusive Dysfunction (CVOD) in a Rat Model of Type 2 Diabetes

2005 ◽  
Vol 173 (4S) ◽  
pp. 283-284
Author(s):  
Istvan Kovanecz ◽  
Monica G. Ferrini ◽  
Hugo H. Davila ◽  
Jacob Rajfer ◽  
Nestor F. Gonzalez-Cadavid
Keyword(s):  
Type 2 Diabetes ◽  
Rat Model

Blockade of Renin Angiotensin System Ameliorates the Cardiac Arrhythmias and Sympathetic Neural Remodeling in Hearts of Type 2 DM Rat Model

2020 ◽  
Vol 20 (3) ◽  
pp. 464-478 ◽  
Author(s):  
Yomna M. Yehya ◽  
Abdelaziz M. Hussein ◽  
Khaled Ezam ◽  
Elsayed A. Eid ◽  
Eman M. Ibrahim ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Cardiac Arrhythmias ◽  
Sympathetic Nerve ◽  
Renin Angiotensin System ◽  
Diabetic Rats ◽  
Angiotensin System ◽  
Type 2 Dm ◽  
Type 2 Diabetic ◽  
Diabetes Induction

Objectives:: The present study was designed to investigate the effects of renin angiotensin system (RAS) blockade on cardiac arrhythmias and sympathetic nerve remodelling in heart tissues of type 2 diabetic rats. Methods:: Thirty-two male Sprague Dawley rats were randomly allocated into 4 equal groups; a) normal control group: normal rats, b) DM group; after type 2 diabetes induction, rats received 2ml oral saline daily for 4 weeks, c) DM+ ACEi: after type 2 diabetes induction, rats were treated with enalapril (10 mg/kg, orally for 4 weeks) and d) DM+ ARBs: after type 2 diabetes induction, rats were treated with losartan (30 mg/kg, orally for 4 weeks). Results:: In type 2 diabetic rats, the results demonstrated significant prolongation in Q-T interval and elevation of blood sugar, HOMA-IR index, TC, TGs, LDL, serum CK-MB, myocardial damage, myocardial MDA, myocardial norepinephrine and tyrosine hydroxylase (TH) density with significant reduction in serum HDL, serum insulin and myocardial GSH and CAT. On the other hand, blockade of RAS at the level of either ACE by enalapril or angiotensin (Ag) receptors by losartan resulted in significant improvement in ECG parameters (Q-T), cardiac enzymes (CK-MB), cardiac morphology, myocardial oxidative stress (low MDA, high CAT and GSH) and myocardial TH density. Conclusions:: RAS plays a role in the cardiac sympathetic nerve sprouting and cardiac arrhythmias induced by type 2 DM and its blockade might have a cardioprotective effect via attenuation of sympathetic nerve fibres remodelling, myocardial norepinephrine contents and oxidative stress.

The effects of apelin treatment on a rat model of type 2 diabetes

2015 ◽  
Vol 60 (1) ◽  
pp. 94-100 ◽  
Author(s):  
Raziye Akcılar ◽  
Sebahat Turgut ◽  
Vildan Caner ◽  
Aydın Akcılar ◽  
Ceylan Ayada ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Rat Model

scholarly journals The Effect of Long-Term Intranasal Serotonin Treatment on Metabolic Parameters and Hormonal Signaling in Rats with High-Fat Diet/Low-Dose Streptozotocin-Induced Type 2 Diabetes

2015 ◽  
Vol 2015 ◽  
pp. 1-17 ◽  
Author(s):  
Kira V. Derkach ◽  
Vera M. Bondareva ◽  
Oxana V. Chistyakova ◽  
Lev M. Berstein ◽  
Alexander O. Shpakov
Keyword(s):  
Type 2 Diabetes ◽  
High Fat Diet ◽  
Low Dose ◽  
Diabetic Rats ◽  
Brain Serotonin ◽  
Serotonin Level ◽  
High Fat ◽  
Brain Serotonin Level ◽  
The Brain

In the last years the treatment of type 2 diabetes mellitus (DM2) was carried out using regulators of the brain signaling systems. In DM2 the level of the brain serotonin is reduced. So far, the effect of the increase of the brain serotonin level on DM2-induced metabolic and hormonal abnormalities has been studied scarcely. The present work was undertaken with the aim of filling this gap. DM2 was induced in male rats by 150-day high-fat diet and the treatment with low dose of streptozotocin (25 mg/kg) on the 70th day of experiment. From the 90th day, diabetic rats received for two months intranasal serotonin (IS) at a daily dose of 20 μg/rat. The IS treatment of diabetic rats decreased the body weight, and improved glucose tolerance, insulin-induced glucose utilization, and lipid metabolism. Besides, it restored hormonal regulation of adenylyl cyclase (AC) activity in the hypothalamus and normalized AC stimulation byβ-adrenergic agonists in the myocardium. In nondiabetic rats the same treatment induced metabolic and hormonal alterations, some of which were similar to those in DM2 but expressed to a lesser extent. In conclusion, the elevation of the brain serotonin level may be regarded as an effective approach to treat DM2 and its complications.

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