scholarly journals Effects of Naringin on Cardiomyocytes From a Rodent Model of Type 2 Diabetes

2021 ◽  
Vol 12 ◽  
Author(s):  
A. Uryash ◽  
A. Mijares ◽  
V. Flores ◽  
J. A. Adams ◽  
J. R. Lopez
Keyword(s):  
Reactive Oxygen Species ◽  
Type 2 Diabetes ◽  
Cell Viability ◽  
Glucose Transport ◽  
Reactive Oxygen ◽  
Nitric Oxide Donor ◽  
Diabetic Patients ◽  
Oxygen Species ◽  
Calpain Activity

Diabetic cardiomyopathy (DCM) is a primary disease in diabetic patients characterized by diastolic dysfunction leading to heart failure and death. Unfortunately, even tight glycemic control has not been effective in its prevention. We have found aberrant diastolic Ca2+ concentrations ([Ca2+]d), decreased glucose transport, elevated production of reactive oxygen species (ROS), and increased calpain activity in cardiomyocytes from a murine model (db/db) of type 2 diabetes (T2D). Cardiomyocytes from these mice demonstrate significant cell injury, increased levels of tumor necrosis factor-alpha and interleukin-6 and expression of the transcription nuclear factor-κB (NF-κB). Furthermore, decreased cell viability, and reduced expression of Kir6.2, SUR1, and SUR2 subunits of the ATP-sensitive potassium (KATP) channels. Treatment of T2D mice with the citrus fruit flavonoid naringin for 4 weeks protected cardiomyocytes by reducing diastolic Ca2+ overload, improving glucose transport, lowering reactive oxygen species production, and suppressed myocardial inflammation. In addition, naringin reduced calpain activity, decreased cardiac injury, increased cell viability, and restored the protein expression of Kir6.2, SUR1, and SUR2 subunits of the KATP channels. Administration of the KATP channel inhibitor glibenclamide caused a further increase in [Ca2+]d in T2D cardiomyocytes and abolished the naringin effect on [Ca2+]d. Nicorandil, a KATP channel opener, and nitric oxide donor drug mimic the naringin effect on [Ca2+]d in T2D cardiomyocyte; however, it aggravated the hyperglycemia in T2D mice. These data add new insights into the mechanisms underlying the beneficial effects of naringin in T2D cardiomyopathy, thus suggesting a novel approach to treating this cardiovascular complication.

scholarly journals Diabetes Mellitus Directs NKT Cells Toward Type 2 and Regulatory Phenotype / Diabetes Melitus Usmerava Diferencijaciju NKT Celija U Pravcu Tip 2 I Regulatornog Fenotipa

2016 ◽  
Vol 17 (1) ◽  
pp. 35-41
Author(s):  
Nevena Gajovic ◽  
Ivan Jovanovic ◽  
Aleksandar Ilic ◽  
Nevena Jeremic ◽  
Vladimir Jakovljevic ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Diabetes Mellitus ◽  
Reactive Oxygen Species ◽  
Reactive Oxygen ◽  
Nkt Cells ◽  
Diabetic Patients ◽  
Oxygen Species ◽  
Chronic Disorder ◽  
Functional Phenotype

Abstract Diabetes mellitus is chronic disorder characterized by hyperglycaemia. Hyperglycaemia induces mitochondrial dysfunction, enhances oxidative stress and thus promotes reactive oxygen species (ROS) production. Earlier studies suggested that reactive oxygen species (ROS) are involved in the pathogenesis of many diseases. Previous studies have revealed that hyperglycaemia changes the functional phenotype of monocytes, macrophages, neutrophils, NK cells and CD8+ T cells. The aim of this study was to investigate whether diabetes affects the functional phenotype of NKT cells. Diabetes mellitus was induced in BALB/c mice by intraperitoneal injection of streptozotocin at a single dose of 170 mg/kg body weight. The number and functional phenotype of splenic NKT cells was assessed by fl ow cytometry, 28 days after diabetes induction. The diabetic condition facilitated the production of antioxidant enzymes, including catalase (p<0.05) and superoxide dismutase. Hyperglycaemia enhanced oxidative stress and thus decreased the number of splenic NKT cells but did not change the percentage of splenic CD3+CD49+ NKT cells that express the activatory receptor NKP46 or produce IFN-γ. However, hyperglycaemia increased the frequency of splenic NKT cells that express KLRG-1 and produce TGF-β, IL-4, and IL-5, and it decreased the frequency of IL-17+ NKT cells. Our study indicates that diabetes mellitus induces oxidative stress and switches the functional phenotype of NKT cells towards type 2 (IL-4 and IL-5 producing NKTs) and regulatory (TGF-β Thproducing NKTs) phenotypes. These findings are correlated with the clinical observation in humans that diabetic patients are more prone to infections and tumours.

scholarly journals CREBRF p.Arg457Gln Promotes Obesity and Improves Insulin Sensitivity by Promoting Preadipocyte Differentiation and Reducing Oxidative Metabolism in Gene-modified Pig Models

2021 ◽  
Author(s):  
Yingying Li ◽  
Hai Wang ◽  
Yuan Liao ◽  
Quanmei Yan ◽  
Zhen Ouyang ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Type 2 Diabetes ◽  
Adipose Tissue ◽  
Oxidative Metabolism ◽  
Reactive Oxygen ◽  
Oxidative Capacity ◽  
Oxygen Species ◽  
Preadipocyte Differentiation ◽  
Human Mutation

Abstract Obesity is one of the most important risk factors for type 2 diabetes (T2DM). The CREBRF missense allele of rs373863828 (p.Arg457Gln) is associated with increased body mass index (BMI), yet reduced risk of T2DM in people with Pacific ancestry. To investigate the functional consequences of the CREBRF variant, we introduced the corresponding human mutation p.Arg457Gln into porcine genome by using a CRISPR/Cas9-mediated homologous recombination (HR)-dependent approach. The CREBRF p.Arg457Gln pig models displayed dramatically increased fat deposition, yet improved sensitivity to insulin. Transcriptome and metabolome analyses of subcutaneous white adipose tissues showed that the CREBRF p.Arg457Gln mutation promoted preadipocyte differentiation, which indicated that obesity was caused by increased number (hyperplasia) rather than size (hypertrophy) of adipocytes. In addition, the oxidative capacity decreased in the adipose tissue of pigs with CREBRF p.Arg457Gln variant. The pre-oxidative metabolite content (4-HNE and MDA) significantly decreased, while activity of antioxidant enzymes (GPX, SOD, and CAT) increased, thereby repressing oxidative metabolism of adipose tissue and reducing level of reactive oxygen species (ROS). The low reactive oxygen species could prevent insulin resistance and reduce risk of obesity-induced type 2 diabetes. This study provides further mechanistic insights into favourable adiposity resulting from CREBRF p.Arg457Gln.

scholarly journals Role of Perivascular Adipose Tissue on Vascular Reactive Oxygen Species in Type 2 Diabetes: A Give-and-Take Relationship: Figure 1

Diabetes ◽  
2015 ◽  
Vol 64 (6) ◽  
pp. 1904-1906 ◽  
Author(s):  
Jaume Padilla ◽  
Victoria J. Vieira-Potter ◽  
Guanghong Jia ◽  
James R. Sowers
Keyword(s):  
Reactive Oxygen Species ◽  
Type 2 Diabetes ◽  
Adipose Tissue ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Perivascular Adipose Tissue

scholarly journals HEPATIC SOD1 GENE EXPRESSION CHANGES IN THE NAFLD PATHOGENESIS IN OBESITY

2021 ◽  
Vol 23 (4) ◽  
pp. 761-766
Author(s):  
A. A. Komar ◽  
D. A. Shunkina (Skuratovsvkaia) ◽  
M. A. Vulf ◽  
H. Q. Vu ◽  
N. M. Todosenko ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Type 2 Diabetes ◽  
Copy Number ◽  
Tricarboxylic Acid Cycle ◽  
Reactive Oxygen ◽  
Metabolic Adaptation ◽  
Control Group ◽  
Obese Patients ◽  
Oxygen Species

Steatosis in the liver in obesity increases the work of mitochondria to utilize excess lipids. An overload of β-oxidation of fatty acids, the tricarboxylic acid cycle, and oxidative phosphorylation leads to a decrease in ATP and an increase in the formation of reactive oxygen species. Normally, mitochondria can efficiently remove elevated levels of reactive oxygen species using the cell's antioxidant system and metabolic adaptation to altered conditions. This study aimed to investigate the role of hepatic SOD expression in the pathogenesis of NAFLD in obesity. It was found that the level of SOD1 expression in the liver in obese patients with and without type 2 diabetes with a BMI > 40 kg/m2 was lower than in healthy donors. The copy number of mitochondrial DNA (mtDNA) in the liver in all obese patients was more than two times lower than in the control group. In the liver of obese patients without type 2 diabetes, the SOD1 protein level and the mtDNA copy number were interrelated and negatively correlated with the area of fatty inclusions. Thus, in obese patients, a decrease in antioxidant defense in the liver leads to the vulnerability of mitochondria, which, in turn, contributes to the progression of steatosis and insulin resistance.

Sign in / Sign up

Export Citation Format

Share Document