Effect of atorvastatin on the angiogenic responsiveness of coronary endothelial cells in normal and streptozotocin (STZ) induced diabetic rats

2014 ◽  
Vol 92 (4) ◽  
pp. 338-349 ◽  
Author(s):  
Kiranj K. Chaudagar ◽  
Anita A. Mehta

Atorvastatin, a lipid lowering agent, possesses various pleiotropic vasculoprotective effects, but its role in coronary angiogenesis is still controversial. Our objective was to study the effects of atorvastatin on the angiogenic responsiveness of coronary endothelial cells (cEC) from normal and diabetic rats. Male Wistar rats were distributed among 9 groups; (i) normal rats, (ii) 30 day diabetic rats, (iii) 60 day diabetic rats, (iv) normal rats administered a low dose of atorvastatin (1 mg/kg body mass, per oral (p.o.), for 15 days); (v) 30 day diabetic rats administered a low dose of atorvastatin; (vi) 60 day diabetic rats administered a low dose of atorvastatin; (vii) normal rats administered a high dose of atorvastatin (5 mg/kg, p.o., for 15 days); (viii) 30 day diabetic rats administered a high dose of atorvastatin; (ix) 60 day diabetic rats administered a high dose of atorvastatin. Each group was further divided into 2 subgroups, (i) sham ischemia–reperfusion and (ii) rats hearts that underwent ischemia–reperfusion. Angiogenic responsiveness the and nitric oxide (NO) releasing properties of the subgroups of cECs were studied using a chorioallantoic membrane assay and the Griess method, respectively. Atorvastatin treatment significantly increased VEGF-induced angiogenic responsiveness and the NO-releasing properties of cECs from all of the subgroups, compared with their respective non-treated subgroups except for the late-phase diabetic rat hearts that underwent ischemia–reperfusion, and the high dose of atorvastatin treatment groups. These effects of atorvastatin were significantly inhibited by pretreatment of cECs with l-NAME, wortmannin, and chelerythrine. Thus, treatment with a low dose of atorvastatin improves the angiogenic responsiveness of the cECs from normal and diabetic rats, in the presence of VEGF, via activation of eNOS–NO release.

1992 ◽  
Vol 9 (3) ◽  
pp. 257-263 ◽  
Author(s):  
D. L. Russell-Jones ◽  
M. Rattray ◽  
V. J. Wilson ◽  
R. H. Jones ◽  
P. H. Sönksen ◽  
...  

ABSTRACT There is evidence that the hormonal control of hepatic IGF-I production is mediated by GH and insulin. To elucidate the role of these hormones further we administered s.c. or i.p. insulin (at 2·5 and 5·0 IU/day) and/or GH (0·8 IU/day) to rats made diabetic with streptozotocin 16 days previously. Hepatic IGF-I production was then assessed by quantifying hepatic IGF-I mRNA levels by autoradiography of Northern blots. Diabetes resulted in a fivefold reduction in hepatic IGF-I mRNA levels (optical density (OD) of the 0·7–1·1 kb band: controls, 1·3±0·09; diabetics, 0·28±0·08; P<0·01), which was not significantly changed by treatment with s.c. insulin (OD: low dose, 0·55±0·05; high dose, 0·58±0·05) or low dose i.p. insulin (OD: 0·40±0·03). High dose i.p. insulin enhanced hepatic IGF-I mRNA levels (OD: 0·93±0·23) compared with diabetic rats (P<0·01) and those given high dose s.c. insulin (P<0·04), despite the blood glucose values being similar in the treated groups (i.p., 4·72±0·29 mmol/l; s.c., 3·32±0·03 mmol/l). Administration of GH alone partially restored the hepatic IGF-I mRNA level (OD: GH-treated, 1·00±0·05; diabetic, 0·28±0·08; P<0·01), whilst having no effect on blood glucose values (diabetic, 36·35±0·45 mmol/l; GH-treated, 38·65±2·39 mmol/l). Additional administration of s.c. insulin completely restored IGF-I mRNA levels to those of controls (OD: low dose, 1·35±0·14; high dose, 1·27 ± 0·18). These observations indicate that insulin and GH are required for full expression of hepatic IGF-I mRNA and that insulin given i.p. is more potent than that given s.c. at stimulating hepatic synthesis of IGF-I.


2012 ◽  
Vol 90 (2) ◽  
pp. 141-153 ◽  
Author(s):  
Tatyana A. Korolenko ◽  
Fedor V. Tuzikov ◽  
Marina S. Cherkanova ◽  
Thomas P. Johnston ◽  
Natalia A. Tuzikova ◽  
...  

The effects of atorvastatin and carboxymethylated β-glucan (CMG) on the lipoprotein-cholesterol (LP-C) and lipoprotein-triglyceride (LP-TG) fractions and subfractions at the early stage of murine hyperlipidemia, and its pleiotropic anti-inflammatory effects, were studied. Atorvastatin and CMG were administered in ICR male mice with acute lipemia induced with a single injection of poloxamer 407 (P-407). A novel small-angle X-ray scattering method for the determination of fractional and subfractional composition of LP-C and LP-TG was used. In P-407-treated animals, there was a drastic increase of total cholesterol and especially TG. Atorvastatin decreased both the total cholesterol and TG, but not to control levels. CMG primarily decreased TG and was not as potent as atorvastatin. P-407 increased atherogenic LDL-C (IDL-C and LDL1–3-C subfractions) and very low-density lipoprotein-C (VLDL-C) (VLDL1–2-C and VLDL3–5-C subfractions) fractions, with an increase of the total anti-atherogenic HDL-C fraction (HDL2-C subfraction). Atorvastatin treatment of lipemia was followed by a decrease in the total LP-C, total LDL-C (LDL1–3-C subfraction), and the LDL1–3-TG subfraction. Additionally, atorvastatin treatment resulted in an increase in the serum matrix metalloproteases activity both in control and P-407-treated mice. In general, high-dose atorvastatin therapy exerts its lipid-lowering and pleiotropic effects in the early stages of acute lipemia induced in mice by treatment with P-407.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Ping-Yen Liu ◽  
Ping-Yen Liu ◽  
Yen-Wen Liu ◽  
Li-Jen Lin ◽  
Jyh-Hong Chen ◽  
...  

Background: By inhibiting HMG-CoA reductase, statins not only inhibit cholesterol biosynthesis, but also decrease the formation of isoprenoids, which are important for mediating signaling through the Rho/Rho kinase (ROCK) pathway. In animal studies, inhibition of ROCK by statins improves endothelial function, decreases inflammation, and prevents atherosclerosis. These so-called cholesterol-independent effects of statins are dose-related and may contribute to some of their clinical benefits. We hypothesize that ezetimibe, which inhibits cholesterol absorption, does not exert these cholesterol-independent effects in humans. Methods and Results: We studied 60 dyslipidemia subjects (n=20 in each arm) in a prospective, randomized, observer-blinded study comparing treatment with simvastatin 40 mg/d or simvastatin/ezetimibe 10/10 mg/d to corresponding placebo tablets for 28 days. Prior statin usage was comparable between the groups and a washout period of 2 weeks was instituted before enrollment. Blood samples for fasting lipids, leukocyte ROCK activity and C-reactive protein (CRP) were collected at days 0 and 28. Baseline demographics, lipid levels, ROCK activity and CRP were not different between the 3 groups. Compared to placebo group, both treatment regimens decreased low-density lipoprotein cholesterol (LDL-C) by 38% and CRP by 32– 42% after 28 days (p<0.001 for both compared to placebo). Although LDL-C and CRP were reduced to comparable levels by either lipid-lowering regimen (p>0.05 between the groups), only simvastatin 40 mg reduced ROCK activity and improved forearm flow-mediated vasodilatation (FMD) (p<0.01 for both compared to baseline). The reduction of ROCK activity with simvastatin 40 mg remained significant even after controlling for changes in LDL-C (p=0.01) and correlated with improvement in FMD (R 2 =0.78, p<0.01). However, there was no correlation between changes in FMD with changes in LDL-C or CRP. Conclusions: These findings suggest that despite comparable decrease in LDL-C and CRP, high-dose statin monotherapy has greater effects on both ROCK activity and endothelial function than low-dose statin and ezetimibe. These findings provide additional evidence of potential statin benefits beyond cholesterol lowering.


1997 ◽  
Vol 272 (2) ◽  
pp. R563-R569 ◽  
Author(s):  
L. R. Leon ◽  
W. Kozak ◽  
J. Peschon ◽  
M. J. Kluger

We examined the effects of injections of systemic [lipopolysaccharide (LPS), 2.5 mg/kg or 50 pg/kg ip] or local (turpentine, 100 microl sc) inflammatory stimuli on fever, motor activity, body weight, and food intake in tumor necrosis factor (TNF) double receptor (TNFR)-knockout mice. A high dose of LPS resulted in exacerbated fevers in TNFR-knockout mice compared with wild-type mice for the early phase of fever (3-15 h); the late phase of fever (16-24 h) and fevers to a low dose of LPS were similar in both groups. Motor activity, body weight, and food intake were similarly reduced in both groups of mice after LPS administration. In response to turpentine, TNFR-knockout and wild-type mice developed virtually identical responses to all variables monitored. These results suggest that 1) TNF modulates fevers to LPS dose dependently, 2) TNF does not modulate fevers to a subcutaneous injection of turpentine, and 3) knockout mice may develop cytokine redundancy in the regulation of the acute phase response to intraperitoneally injected LPS or subcutaneously injected turpentine.


2018 ◽  
Vol 38 (2) ◽  
Author(s):  
Qian Zhang ◽  
Xinhua Xiao ◽  
Jia Zheng ◽  
Ming Li ◽  
Miao Yu ◽  
...  

Increasing evidence shows that diabetes causes cardiac dysfunction. We hypothesized that a glucagon-like peptide-1 (GLP-1) analog, liraglutide, would attenuate cardiac dysfunction in diabetic rats. A total of 24 Sprague–Dawley (SD) rats were divided into two groups fed either a normal diet (normal, n=6) or a high-fat diet (HFD, n=18) for 4 weeks. Then, the HFD rats were injected with streptozotocin (STZ) to create a diabetic rat model. Diabetic rats were divided into three subgroups receiving vehicle (diabetic, n=6), a low dose of liraglutide (Llirag, 0.2 mg/kg/day, n=6), or a high dose of liraglutide (Hlirag, 0.4 mg/kg/day, n=6). Metabolic parameters, systolic blood pressure (SBP), heart rate (HR), left ventricular (LV) function, and whole genome expression of the heart were determined. Diabetic rats developed insulin resistance, increased blood lipid levels and oxidative stress, and impaired LV function, serum adiponectin, nitric oxide (NO). Liraglutide improved insulin resistance, serum adiponectin, NO, HR, and LV function and reduced blood triglyceride (TG), total cholesterol (TC) levels, and oxidative stress. Moreover, liraglutide increased heart nuclear receptor subfamily 1, group H, member 3 (Nr1h3), peroxisome proliferator activated receptor (Ppar) α (Pparα), and Srebp expression and reduced diacylglycerol O-acyltransferase 1 (Dgat) and angiopoietin-like 3 (Angptl3) expression. Liraglutide prevented cardiac dysfunction by activating the PPARα pathway to inhibit Dgat expression and oxidative stress in diabetic rats.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
A A Momtazi-Borojeni ◽  
M Banach ◽  
M Majeed ◽  
A Sahebkar

Abstract Background and purpose The present study was aimed to evaluate lipid-lowering and anti-atherogenic effect of an intravenous (IV) curcumin in the rabbit fed high cholesterol diet (HCD). Methods New Zealand white male rabbits (4–6 months old, n=25, weight 2.286±0.256 kg)were fed on a normal chow enriched with 0.5% (w/w) cholesterol for 5 weeks. Atherosclerotic rabbits were randomly divided into three group, including a control group receiving intravenous (IV) injection of saline buffer, two treatment groups receiving IV injection of curcumin at two different dosages, 1and 10 mg/kg/week, for 4 weeks. Blood samples were collected from fasted rabbits at pre- (week 5) and post-treatment (week 11) points for analysis of serum lipid levels, including low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), triglyceride (TG), and total cholesterol (TC). Aortic arch atherosclerotic lesions were assessed using hematoxylin and eosin (H&E) staining. Results To evaluate curcumin's effects on the hyperlipidemic states and atherosclerosis plaque, HCD-fed rabbits were weekly treated with the injectable curcumin at the low (1mg/kg/week) and high (10 mg/kg/week) doses by 4 weeks. At week 4 in compared with the control group, low-dose curcumin could reduce serum levels of LDL-c, HDL-c, TG, and TC by −6.22% ±1.77, −35.24% ±12.49, −29.84% ±10.14, −14.19% ±5.19, respectively. In the case of high-dose curcumin, serum levels of LDL-c, HDL-c, TG, and TC were changed by −44.36%±3.24, 14.05% ±6.39, −25.92% ±5.57, −56.59% ±10.22, respectively, when compared with the control group at week 4. Low-dose curcumin after 4 weeks' treatment could reduce serum levels LDL-c, HDL-c, TG, and TC up to 103±28 mg/dL, 18.33±4.66 mg/dL, 97.5±31 mg/dL, and 356.5±19.5 mg/dL, respectively, when compared with the base line levels (week 0). High-dose curcumin after 4 weeks' treatment could decrease serum levels of LDL-c, HDL-c, TG, HDL-c, and TC up to 207±17.04 mg/dL, 15.5±0.5 mg/dL, 333±40 mg/dL, and 514.5±22.23 mg/dL, respectively (Figure). H&E staining declared that atherosclerotic lesion grades were significantly lower in the curcumin-treated groups than the control group. Changes of lipids in rabbits on curcumin Conclusions The injectable curcumin at the low (1mg/kg) and high (10 mg/kg) could significantly improve dyslipidemia and alleviate atherosclerotic lesion in HCD-induced atherosclerotic rabbits.


2005 ◽  
Vol 186 (2) ◽  
pp. 367-376 ◽  
Author(s):  
Tsuneo Kobayashi ◽  
Takayuki Matsumoto ◽  
Katsuo Kamata

We have investigated the mechanisms underlying the changes in vascular contractile responsiveness induced by insulin and IGF-I in established streptozotocin-induced diabetic rats. The contractile response to noradrenaline (NA) in organ-cultured diabetic rat aortae cultured with insulin or IGF-I was significantly greater than the corresponding responses in (a) diabetic rat aortae cultured in serum-free medium and (b) control rat aortae cultured with insulin or IGF-I. In aortae from which the endothelium was removed after organ culture the contractile response to NA was greater in those cultured with insulin or IGF-I than in those cultured in serum-free medium. This was not true of aortae endothelium denuded before organ culture. The IGF-I-induced enhancement was prevented by treatment with indomethacin (cyclo-oxygenase inhibitor), SQ29548 (thromboxane (TX) A2 receptor antagonist) or fregrelate (TXA2 synthase inhibitor). IGF-I-induced production of TXB2, a metabolite of TXA2, was greater in diabetic than in control aortae and was attenuated by endothelium denudation, indomethacin or AG1024 (IGF-I receptor inhibitor). The expression of the protein and mRNA for the IGF-I receptor (as assessed by RT-PCR and immunohistochemistry) was markedly increased within endothelial cells in diabetic aortae but only slightly increased within smooth muscle cells (versus control rat aortae). Thus, the NA-induced contractile response in aortae from diabetic rats was enhanced by both insulin and IGF-I and this enhancement may be mediated by sustained cyclo-oxygenase-dependent TXA2 production from endothelial cells. The observed enhancement of IGF-I receptor expression within endothelial cells may be causally related to the potentiation of vascular contractility and the increase in TXA2 production.


PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3185 ◽  
Author(s):  
Előd Nagy ◽  
Enikő Vajda ◽  
Camil Vari ◽  
Sándor Sipka ◽  
Ana-Maria Fárr ◽  
...  

ObjectiveThis study aimed to quantify the cartilage- and subchondral bone-related effects of low-dose and high-dose meloxicam treatment in the late phase of mono-iodoacetate-induced osteoarthritis of the stifle.MethodsThirty-four male Wistar rats received intra-articular injection of mono-iodoacetate to trigger osteoarthritis; 10 control animals (Grp Co) received saline. The mono-iodoacetate-injected rats were assigned to three groups and treated from week 4 to the end of week 7 with placebo (Grp P,n = 11), low-dose (GrpM Lo, 0.2 mg/kg,n = 12) or high-dose (GrpM Hi, 1 mg/kg,n = 11) meloxicam. After a period of 4 additional weeks (end of week 11) the animals were sacrificed, and the stifle joints were examined histologically and immunohistochemically for cyclooxygenase 2, in conformity with recommendations of the Osteoarthritis Research Society International. Serum cytokines IL-6, TNFα and IL-10 were measured at the end of weeks 3, 7, and 11.ResultsCompared with saline-treated controls, animals treated with mono-iodoacetate developed various degrees of osteoarthritis. The cartilage degeneration score and the total cartilage degeneration width were significantly lower in both the low-dose (p = 0.012 andp = 0.014) and high-dose (p = 0.003 andp = 0.006) meloxicam-treated groups than in the placebo group. In the subchondral bone, only high-dose meloxicam exerted a significant protective effect (p = 0.011). Low-grade Cox-2 expression observed in placebo-treated animals was abolished in both meloxicam groups. Increase with borderline significance of TNFα in GrpP from week 3 to week 7 (p = 0.049) and reduction of IL-6 in GrpM Lo from week 3 to week 11 (p = 0.044) were observed.ConclusionIn this rat model of osteoarthritis, both low-dose and high-dose meloxicam had a chondroprotective effect, and the high dose also protected against subchondral bone lesions. The results suggest a superior protection of the high-dose meloxicam arresting the low-grade inflammatory pathway accompanied by chronic cartilage deterioration.


2015 ◽  
Vol 05 (11) ◽  
pp. 149-161
Author(s):  
Abdulmonim A. Alqasim ◽  
Sami H. Hammadi ◽  
Ghazi A. Bamagous ◽  
Essam Eldin M. Noureldin ◽  
Hussam H. Madi

2016 ◽  
Vol 8 (4) ◽  
pp. 414-421 ◽  
Author(s):  
Rasheed Bolaji IBRAHIM ◽  
Jubril Olayinka AKOLADE ◽  
Raliat Abimbola ALADODO ◽  
Omoaruemike Ebele OKEREKE ◽  
Sarah Abimbola AKANDE

The antidiabetic potentials of Heliotropium indicum L. leaf aqueous (HILA) extract used for the management of diabetes by Traditional Medicinal Practitioners (TMPs) in Nigeria was assessed. Alloxan (ALX)-induced hyperglycaemic rats were orally administered with known folkloric dosage of 30 and 75 mg/kg b. wt. of HILA extract, once a day, for 14 days. Fasting blood glucose (FBG) levels were monitored and pancreatic histology was examined. Net hepatic glycogen (GLY) concentration and lipid profiles were also determined. Prior to treatment, ALX-induced hyperglycaemia (>250 mg/dL) was established in rats. Oral administration of 30 and 75 mg/kg b. wt. HILA extract to diabetic rats for 14 days caused significant reduction in FBG to baseline values observed in non-diabetic conditions. Treatment with HILA extract also showed improvement in lipid abnormalities observed in hyperglycaemic condition, levels of triglyceride, total cholesterol and LDL-cholesterol were significantly reduced and HDL-cholesterol increased resulting in improved artherogenic index. Hepatic GLY concentration was significantly increased in diabetic rat treated with the extract. Histological examinations showed degenerated and sparse pancreatic islets β-cells in non-treated diabetic rat, whereas microscopy of treated rats showed mild to normal architecture with enriched β-cells. Preliminary phytochemical profiling of the extract revealed the presence of alkaloids (2.54 mg/g), saponins (0.28 mg/g), phenols (0.04 mg/g) and anthraquinones (0.01 mg/g). Results from this study revealed that the aqueous leaf extract of H. indicum possesses not only antihyperglycaemic, but also antidyslipidemic activities, that may prove to be of clinical importance in the management of diabetes and associated secondary complications.


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