Myocardial performance of STZ-diabetic DOCA-hypertensive rats

1992 ◽  
Vol 263 (6) ◽  
pp. H1798-H1805 ◽  
Author(s):  
S. Dai ◽  
J. H. McNeill

Myocardial performance of streptozotocin (STZ)-diabetic deoxycorticosterone acetate (DOCA)-hypertensive rats was examined using the isolated working heart apparatus at various time periods after induction of the experimental diseases. Blood pressure, pulse rate, and plasma levels of glucose, insulin, cholesterol, and triglycerides, as well as ventricular weight-to-body weight ratio, were also determined. In nondiabetic rats it was found that DOCA hypertension was associated with an increase in plasma cholesterol, a decrease in circulating insulin level, lower weight gain, and ventricular enlargement compared with control rats. Diabetic rats developed myocardial dysfunction in a time-dependent manner and exhibited hyperglycemia, hypoinsulinemia, bradycardia, and ventricular enlargement. Compared with the normotensive diabetic animals, STZ-diabetic DOCA-hypertensive rats showed a similar magnitude of myocardial dysfunction and a greater degree of ventricular enlargement, but significantly less severe hyperglycemia. It is concluded that DOCA-induced hypertension does not aggravate the severity of myocardial dysfunction developed in STZ-diabetic rats. It is also suggested that DOCA may have an action on glucose metabolism either directly or via an effect on insulin secretion.

1992 ◽  
Vol 70 (12) ◽  
pp. 1583-1589 ◽  
Author(s):  
Soter Dai ◽  
John H. McNeill

The present study compares the cardiovascular consequences of a 6-week fructose feeding in nondiabetic and streptozotocin-diabetic rats. Myocardial performance of these animals was determined using the isolated perfused working heart preparation. Systolic blood pressure, pulse rate, ventricular weight/body weight ratio, and plasma levels of glucose, insulin, triglycerides, and cholesterol were measured. In nondiabetic rats, fructose drinking caused significant increases in blood pressure, pulse rate, and plasma concentrations of insulin and triglycerides. Streptozotocin-diabetic animals exhibited significantly less body weight growth, slower pulse rate, higher plasma levels of cholesterol and triglycerides, ventricular enlargement, and functional impairment of the myocardium. The fructose-loaded diabetic rats had larger increases in plasma cholesterol and triglycerides than did control fructose-fed rats, but the fructose-induced increases in blood pressure and pulse rate were attenuated significantly. However, plasma levels of glucose and insulin and the degree of ventricular enlargement and myocardial dysfunction were not significantly different from those of control diabetic rats. These results show that fructose loading for 6 weeks can cause increases in blood pressure, pulse rate, and plasma lipids in both nondiabetic and diabetic rats. However, fructose ingestion does not significantly alter glycemic control or affect the development of myocardial dysfunction in streptozotocin-diabetic rats.Key words: fructose, diabetes, hypertension, hyperlipidemia, myocardial dysfunction.


1986 ◽  
Vol 64 (6) ◽  
pp. 669-672 ◽  
Author(s):  
Arun G. Tahiliani ◽  
John H. McNeill

Streptozotocin-diabetic rats were treated with a combination of triiodothyronine and carnitine for 6 weeks. These compounds were used as they are known to correct the diabetes-induced depression of cardiac myosin ATPase and sarcoplasmic reticular (SR) calcium uptake, respectively. Myocardial performance, which was assessed using the working heart preparation, revealed a depression of function in untreated diabetics when compared with controls at most left atrial filling pressures. Hearts from diabetic rats treated with the combination exhibited depression at only the higher filling pressures as compared with untreated or treated controls. The results suggest that functional alterations occurring as a result of diabetes cannot be accounted for by the depression of cardiac myosin ATPase and SR calcium uptake alone.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Ahmed Amir Radwan Sayed

The efficacy of Ferulsinaic acid (FA) to modulate the antioxidant enzymes and to reduce oxidative stress induced-diabetic nephropathy (DN) was studied. Rats were fed diets enriched with sucrose (50%, wt/wt), lard (30%, wt/wt), and cholesterol (2.5%, wt/wt) for 8 weeks to induce insulin resistance. After a DN model was induced by streptozotocin; 5, 50 and 500 mg/kg of FA were administrated by oral intragastric intubation for 12 weeks. In FA-treated diabetic rats, glucose, kidney/body weight ratio, creatinine, BUN, albuminurea, and creatinine clearance were significantly decreased compared with non treated diabetic rats. Diabetic rats showed decreased activities of SOD and GSH; increased concentrations of malondialdehyde and IL-6 in the serum and kidney, and increased levels of 8-hydroxy-2′-deoxyguanosine in urine and renal cortex. FA-treatment restored the altered parameters in a dose-dependent manner. The ultra morphologic abnormalities in the kidney of diabetic rats were markedly ameliorated by FA treatment. Furthermore, FA acid was found to attenuate chronic inflammation induced by both Carrageenan and dextran in rats. We conclude that FA confers protection against injuries in the kidneys of diabetic rats by increasing activities of antioxidant enzymes and inhibiting accumulation of oxidized DNA in the kidney, suggesting a potential drug for the prevention and therapy of DN.


2021 ◽  
Vol 18 (7) ◽  
pp. 1493-1497
Author(s):  
Lai-zeng Yu ◽  
Xue-peng Zhang ◽  
Ying-xin Wang

Purpose: To investigate the effect of Polygonatum sibiricum extract (PSE) on streptozotocin-induced diabetic rats. Methods: PSE was obtained by steeping the dried Polygonatum sibiricum in water at 60 oC three times, each for 1 h, before first drying in an oven at 100C and then freeze-drying the final extract, thus obtained. Diabetic model rats were prepared by a single intraperitoneal injection of a freshly prepared solution of streptozotocin (50 mg/kg). The rats were randomly divided into 6 groups of ten rats each: negative control, normal control, reference (glibenclamide1 mg/kg) as well as PSE groups, (35, 70 and 140 mg/kg). Blood glucose and plasma insulin levels were measured to determine antihyperglycemic effect. Oxidative stress was evaluated in liver and kidney by their antioxidant markers, viz, lipid peroxidation (LPO), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx) and catalase (CAT). Blood serum levels of creatinine and urea were determined in both diabetic control and treated rats. Results: Compared with diabetic rats, oral administration of PSE at a concentration of 120 mg/kg daily for 30 days showed a significant decrease in fasting blood glucose (118.34 ± 3.29 mg/dL) (p < 0.05) and increased insulin level (12.86± 0.62 uU/mL, p < 0.05). Furthermore, it significantly reduced biochemical parameters (serum creatinine, 0.83 ±0.21 mg/dL, p < 0.05) and serum urea (43.26±1.42 mg/dL, p < 0.05). Conclusion: The results suggest that PSE may effectively normalize impaired antioxidant status in streptozotocin-induced diabetes in a dose-dependent manner. Thus, PSE has a protective effect against lipid peroxidation by scavenging free radicals, restoration of insulin function, and reduction of the incidence of complications.


2020 ◽  
Vol 11 (4) ◽  
pp. 5067-5070
Author(s):  
Pang Jyh Chayng ◽  
Nurul Ain ◽  
Kaswandi Md Ambia ◽  
Rahim Md Noah

The purpose of this project is to study the anti-diabetic effect of on a diabetic rat model. A total of Twenty male Sprague rats were used and it randomly distributed into four groups which are Group I: , Group II: negative control, Group III: and Group IV: and . In diabetic model were induced with via injection at the dosage of 65mg/kg. and FBG (Fasting Blood Glucose) level of diabetic rats were assessed every three days. Blood was collected via cardiac puncture at day 21 after the induction of treatment. Insulin level of the rats was assessed with the Mercodia Rat Insulin ELISA kit. FBG level of group I (12.16 ±3.96, p&lt;0.05) and group IV (11.34 ±3.67, p&lt;0.05) were significantly decreased. Meanwhile, the for all rats did not show any significant increase. However, the insulin level was escalated in group IV (0.74+0.25, p&lt;0.05) significantly. The present study shows that the and the combination of and lowered blood glucose level and enhanced insulin secretion.


2019 ◽  
Vol 19 (4) ◽  
pp. 503-510 ◽  
Author(s):  
Mohamed Eddouks ◽  
Farid Khallouki ◽  
Robert W. Owen ◽  
Morad Hebi ◽  
Remy Burcelin

Aims: Arganimide A (4,4-dihydroxy-3,3-imino-di-benzoic acid) is a compound belonging to a family of aminophenolics found in fruit of Argania spinosa. The purpose of this study was to investigate the glucose and lipid lowering activity of Arganimide A (ARG A). Methods: The effect of a single dose and daily oral administration of Arganimide A (ARG A) on blood glucose levels and plasma lipid profile was tested in normal and streptozotocin (STZ) diabetic rats at a dose of 2 mg/kg body weight. Results: Single oral administration of ARG A reduced blood glucose levels from 26.50±0.61 mmol/L to 14.27±0.73 mmol/L (p<0.0001) six hours after administration in STZ diabetic rats. Furthermore, blood glucose levels were decreased from 5.35±0.30 mmol/L to 3.57±0.17 mmol/L (p<0.0001) and from 26.50±0.61 mmol/L to 3.67±0.29 mmol/L (p<0.0001) in normal and STZ diabetic rats, respectively, after seven days of treatment. Moreover, no significant changes in body weight in normal and STZ rats were shown. According to the lipid profile, the plasma triglycerides levels were decreased significantly in diabetic rats after seven days of ARG treatment (p<0.05). Moreover, seven days of ARG A treatment decreased significantly the plasma cholesterol concentrations (p<0.001). Conclusion: ARG A possesses glucose and lipid-lowering activity in diabetic rats and this natural compound may be beneficial in the treatment of diabetes.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Leah Cannon ◽  
Tadeusz Marciniec ◽  
Bryony Mearns ◽  
Robert M Graham ◽  
Diane Fatkin

Left ventricular hypertrophy (LVH) develops as a compensatory response to myocardial dysfunction due to diverse causes, but is nonetheless a major risk factor for premature cardiovascular morbidity and mortality. It is thus unclear if regressing LVH is beneficial or may worsen patient outcome. To evaluate the effects of LVH regression, we developed a transgenic mouse model in which the expression of a familial hypertrophic cardiomyopathy (FHC)-inducing mutation (R403Q alpha-MHC) can be regulated in a temporal and dose-dependent manner. In this model, transgene expression can be shut off by feeding with a tetracycline analogue (doxycycline). Serial echocardiography and histology studies were performed in a cohort of mice expressing the FHC mutant (“gene-on”) and in wildtype (WT) littermates. A second cohort of WT and 403/+ mice was randomised to placebo or doxycycline (“gene off”) from 6 (Dox6) or 20 weeks (Dox20) and evaluated at 40 weeks of age. Compared to WT littermates, “gene on” 403/+ mice showed increased LV mass, LV end-diastolic diameter (LVDD) and left atrial diameter (LAD), and reduced fractional shortening (LVFS), with changes evident from 12 weeks of age. LV sections from 403/+ mice showed typical features of FHC: myofibre disarray and interstitial fibrosis. LV mass, LV function and myocardial histology were unchanged in both male and female placebo- vs Dox6 or Dox20 mice at 40 weeks (Table 1 ). Thus, consistent with the major LV thickening in FHC humans occurring in adolescence, overexpression of R403Q for only 6 weeks is sufficient to trigger the complete LVH phenotypic response. Moreover, switching off the genetic trigger for LVH in 403/+ mice at 6 weeks (prior to overt disease manifestation) or 20 weeks (established disease) does not induce regression of LVH or exacerbate contractile dysfunction. Interventions to induce LVH regression may, therefore, need to be directed at downstream factors in hypertrophic pathways. Table 1. Echo data for male WT and 403/+ mice aged 40 weeks


2021 ◽  
Vol 1 (2) ◽  
pp. 1-8
Author(s):  
Abubakar A. Yusuf ◽  
Toheeb D. Yissa ◽  
Abdulhakeem Rotimi Agboola ◽  
Sodiq M Balogun ◽  
Peter O. Adeboye ◽  
...  

Background: The prevalence of diabetes mellitus is increasing on a global trend. The aim of the present study is to identify the most effective antioxidants and hypoglycemic fraction of Azanza garckeana. Methods: The fractions (nhexane or ethyl-acetate or aqueous) of A. garckeana were administered to the alloxan-induced diabetic rats at doses of 100, 200, and 400 mg/kg for 15 days. Antioxidants activities were evaluated at concentrations of 62.5, 125, 250, and 500 µg/mL using the DPPH scavenging assay. Results: Results revealed that both the hexane, ethyl-acetate, and aqueous fractions exhibited hypoglycemic and antioxidants activities in a dose-dependent manner. The n-hexane fraction demonstrated highest percentage DPPH scavenging effect of 26.34±3.43, 38.44±4.35, 59.34±3.45, and 74.83±5.35 at 62.5, 125, 250, and 500 µg/mL respectively. The ethyl-acetate fraction demonstrated 19.33±2.98, 28.94±3.24, 47.34±2.90, and 57.82±4.54 respectively while the aqueous fraction exhibited the least activities of 12.45±23.45, 18.64±2.94, 27.94±3.89, and 39.43±3.89 at concentrations of 62.5, 125, 250, and 500 µg/mL respectively. In addition, the n-hexane fraction demonstrated the most significant hypoglycemic effect with the highest glucose reduction of 58.97 ±3.45 %, 63.86±5.35 %, and 66.51±4.35 %, ethyl acetate fraction demonstrated glucose reduction of 7.55±0.54%, 21.77±2.35 %, and 29.56±3.46 % while the aqueous fraction demonstrated the least hypoglycemic effect of 9.89±2.67 %, 18.09±3.45 %, and 18.87±3.24 at 100, 200 and 400 mg/kg bw respectively. Conclusion: The n-hexane fraction of Azanza garckeana extract could serve as a reservoir of bioactive agents that could be useful for the development of a new anti-diabetic agent


Diabetology ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 190-204
Author(s):  
Ahmed Al-Humadi ◽  
Athina Strilakou ◽  
Hussam Al-Humadi ◽  
Rafal Al-Saigh ◽  
Emmanouel Agapitos ◽  
...  

Choline (Ch) is an essential molecule of substantial importance for the optimal development and function of several biological systems. Ch deprivation has been linked with abnormal fat metabolism, insulin resistance, and myocardial dysfunction. The current study provides evidence of an exacerbation of streptozotocin-induced cardiomyopathy in adult diabetic Wistar rats by dietary Ch deprivation through the administration of a Ch-deprived diet (CDD). Twenty-four adult male Wistar rats were randomly separated into four groups: control, diabetic (DM), choline-deprived through choline-deprived diet (CD), and diabetic choline-deprived (DM + CD). After five weeks of dietary intervention, myocardium echocardiographic and histological assessments were performed. Choline-deprived diabetic rats exhibited significantly slower heart rate, significantly higher myocardial ejection velocity and left ventricle wall tension index with a concomitant significant decreased LV posterior wall thickness as compared to diabetic rats fed on a standard diet. Moreover, histopathological evidence demonstrated an exacerbation of myocardial inflammation and fibrosis associated with significant up-regulation of VEGF expression in the diabetic rat myocardium as a result of Ch deprivation. The study’s findings are of particular significance since the examined experimental approach introduces a previously uncharacterised comorbidity simulation with regards to myocardial structure and functional profiling.


INDIAN DRUGS ◽  
2017 ◽  
Vol 54 (11) ◽  
pp. 58-60
Author(s):  
N Solanki ◽  
◽  
S. K Bhavsar

Ficus racemosa is used in traditional system of medicine for various health problems and diseases, and is commonly known as Gular fig. The main objective was to study its effects against streptozotocin induced diabetic neuropathy by structural and functional marker. Investigation of diabetic neuropathy was carried out through functional and structural assessment in streptozotocin induced in diabetic rats. Diabetic rats were treated for 28 days in dose dependent manner of Ficus racemosa aqueous extract (250 mg/kg and 500 mg/kg) and ethanolic extract (200 mg/kg and 400 mg/kg). Study showed marked protection observed by Ficus racemosa in hippocampus region of brain and sciatic nerve tissues. Ficus racemosa treatment showed improvement in functional and structural markers, which strongly suggest its protective role in diabetic neuropathy.


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