Oxidative stress and diabetes: What can we learn about insulin resistance from antioxidant mutant mouse models?

Abstract Background Myocardial ischemia reperfusion injury (MIRI) is defined as tissue injury in the pathological process of progressive aggravation in ischemic myocardium after the occurrence of acute coronary artery occlusion. Research has documented the involvement of microRNAs (miRs) in MIRI. However, there is obscure information about the role of miR-130a-5p in MIRI. Herein, this study aims to investigate the effect of miR-130a-5p on MIRI. Methods MIRI mouse models were established. Then, the cardiac function and hemodynamics were detected using ultrasonography and multiconductive physiological recorder. Functional assays in miR-130a-5p were adopted to test the degrees of oxidative stress, mitochondrial functions, inflammation and apoptosis. Hematoxylin and eosin (HE) staining was performed to validate the myocardial injury in mice. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was employed to assess the expression patterns of miR-130a-5p, high mobility group box (HMGB)2 and NF-κB. Then, dual-luciferase reporter gene assay was performed to elucidate the targeting relation between miR-130a-5p and HMGB2. Results Disrupted structural arrangement in MIRI mouse models was evident from HE staining. RT-qPCR revealed that overexpressed miR-130a-5p alleviated MIRI, MIRI-induced oxidative stress and mitochondrial disorder in the mice. Next, the targeting relation between miR-130a-5p and HMGB2 was ascertained. Overexpressed HMGB2 annulled the protective effects of miR-130a-5p in MIRI mice. Additionally, miR-130a-5p targets HMGB2 to downregulate the nuclear factor kappa-B (NF-κB) axis, mitigating the inflammatory injury induced by MIRI. Conclusion Our study demonstrated that miR-130a-5p suppresses MIRI by down-regulating the HMGB2/NF-κB axis. This investigation may provide novel insights for development of MIRI treatments.

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Dibenzoylthiamine Has Powerful Antioxidant and Anti-Inflammatory Properties in Cultured Cells and in Mouse Models of Stress and Neurodegeneration

Biomedicines ◽

10.3390/biomedicines8090361 ◽

2020 ◽

Vol 8 (9) ◽

pp. 361

Author(s):

Margaux Sambon ◽

Anna Gorlova ◽

Alice Demelenne ◽

Judit Alhama-Riba ◽

Bernard Coumans ◽

...

Keyword(s):

Oxidative Stress ◽

Neurodegenerative Diseases ◽

Cell Line ◽

Mouse Models ◽

Cultured Cells ◽

Therapeutic Potential ◽

Motor Dysfunction ◽

Oxidative Stress Marker ◽

Bv2 Cells ◽

Anti Inflammatory

Thiamine precursors, the most studied being benfotiamine (BFT), have protective effects in mouse models of neurodegenerative diseases. BFT decreased oxidative stress and inflammation, two major characteristics of neurodegenerative diseases, in a neuroblastoma cell line (Neuro2a) and an immortalized brain microglial cell line (BV2). Here, we tested the potential antioxidant and anti-inflammatory effects of the hitherto unexplored derivative O,S-dibenzoylthiamine (DBT) in these two cell lines. We show that DBT protects Neuro2a cells against paraquat (PQ) toxicity by counteracting oxidative stress at low concentrations and increases the synthesis of reduced glutathione and NADPH in a Nrf2-independent manner. In BV2 cells activated by lipopolysaccharides (LPS), DBT significantly decreased inflammation by suppressing translocation of NF-κB to the nucleus. Our results also demonstrate the superiority of DBT over thiamine and other thiamine precursors, including BFT, in all of the in vitro models. Finally, we show that the chronic administration of DBT arrested motor dysfunction in FUS transgenic mice, a model of amyotrophic lateral sclerosis, and it reduced depressive-like behavior in a mouse model of ultrasound-induced stress in which it normalized oxidative stress marker levels in the brain. Together, our data suggest that DBT may have therapeutic potential for brain pathology associated with oxidative stress and inflammation by novel, coenzyme-independent mechanisms.

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Are insulin-resistance and oxidative stress cause or consequence of aging

Experimental Biology and Medicine ◽

10.1177/1535370220929621 ◽

2020 ◽

Vol 245 (14) ◽

pp. 1260-1267

Author(s):

Sylwia Dzięgielewska-Gęsiak ◽

Dorota Stołtny ◽

Alicja Brożek ◽

Małgorzata Muc-Wierzgoń ◽

Ewa Wysocka

Keyword(s):

Oxidative Stress ◽

Insulin Resistance ◽

Antioxidant Status ◽

Antioxidant Defense ◽

Total Antioxidant Status ◽

Thiobarbituric Acid ◽

Elderly Individuals ◽

Total Antioxidant ◽

Antioxidant Defense Systems ◽

Antioxidant Markers

Insulin resistance (IR) may be associated with oxidative stress and leads to cardiovascular disorders. Current research focuses on interplay between insulin-resistance indices and oxidant-antioxidant markers in elderly individuals with or without insulin-resistance. The assessment involved anthropometric data (weight, height, BMI, percentage of body fat (FAT)) and biochemical tests (glucose, lipids, serum insulin and plasma oxidant-antioxidant markers: Thiobarbituric Acid-Reacting Substances (TBARS), Cu,Zn-superoxide dismutase (SOD-1) and total antioxidant status). Insulin resistance index (IR) assuming a cut-off point of 0.3 allows to divides groups into: insulin sensitive group (InsS) IR < 0,3 ( n = 35, median age 69.0 years) and insulin-resistant group (InsR) IR ≥ 0.3 ( n = 51, median age 71.0 years). Lipids and antioxidant defense system markers did not differentiate the investigated groups. In the InsR elderly group, the FAT was increased ( P < 0.000003) and TBARS ( P = 0.008) concentration decreased in comparison with InsS group. A positive correlation for SOD-1 and total antioxidant status ( P < 0.05; r = 0.434) and a negative correlation for TBARS and age ( P < 0.05 with r = −0.421) were calculated in InsR individuals. In elderly individuals, oxidative stress persists irrespective of insulin-resistance status. We suggest that increased oxidative stress may be consequence of old age. An insulin action identifies those at high risk for atherosclerosis, via congruent associations with oxidative stress and extra- and intra-cellular antioxidant defense systems. Thus, we maintain that insulin-resistance is not the cause of aging. Impact statement Insulin resistance is associated with oxidative stress leading to cardiovascular diseases. However, little research has been performed examining elderly individuals with or without insulin-resistance. We demonstrate that antioxidant defense systems alone is not able to abrogate insulin action in elderly individuals at high risk for atherosclerosis, whereas the combined oxidant-antioxidant markers (thiobarbituric acid-reacting substances (TBARS), Cu,Zn-superoxide dismutase (SOD-1), and total antioxidant status (TAS)) might be more efficient and perhaps produce better clinical outcome. In fact, a decrease in oxidative stress and strong interaction between antioxidant defense can be seen only among insulin-resistant elderly individuals. This is, in our opinion, valuable information for clinicians, since insulin-resistance is considered strong cardiovascular risk factor.

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Nitric oxide synthase 3 deficiency limits adverse ventricular remodeling after pressure overload in insulin resistance

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00744.2010 ◽

2011 ◽

Vol 301 (5) ◽

pp. H2093-H2101 ◽

Cited By ~ 5

Author(s):

Baptiste Kurtz ◽

Helene B. Thibault ◽

Michael J. Raher ◽

John R. Popovich ◽

Sharon Cawley ◽

...

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Insulin Resistance ◽

Mitochondrial Respiration ◽

Pressure Overload ◽

Lv Remodeling ◽

Stress Levels ◽

Nitric Oxide Synthase 3 ◽

And Function ◽

Oxide Synthase

Insulin resistance (IR) and systemic hypertension are independently associated with heart failure. We reported previously that nitric oxide synthase 3 (NOS3) has a beneficial effect on left ventricular (LV) remodeling and function after pressure-overload in mice. The aim of our study was to investigate the interaction of IR and NOS3 in pressure-overload-induced LV remodeling and dysfunction. Wild-type (WT) and NOS3-deficient (NOS3−/−) mice were fed either a standard diet (SD) or a high-fat diet (HFD) to induce IR. After 9 days of diet, mice underwent transverse aortic constriction (TAC). LV structure and function were assessed serially using echocardiography. Cardiomyocytes were isolated, and levels of oxidative stress were evaluated using 2′,7′-dichlorodihydrofluorescein diacetate. Cardiac mitochondria were isolated, and mitochondrial respiration and ATP production were measured. TAC induced LV remodeling and dysfunction in all mice. The TAC-induced decrease in LV function was greater in SD-fed NOS3−/− mice than in SD-fed WT mice. In contrast, HFD-fed NOS3−/− developed less LV remodeling and dysfunction and had better survival than did HFD-fed WT mice. Seven days after TAC, oxidative stress levels were lower in cardiomyocytes from HFD-fed NOS3−/− than in those from HFD-fed WT. Nω-nitro-l-arginine methyl ester and mitochondrial inhibitors (rotenone and 2-thenoyltrifluoroacetone) decreased oxidative stress levels in cardiomyocytes from HFD-fed WT mice. Mitochondrial respiration was altered in NOS3−/− mice but did not worsen after HFD and TAC. In contrast with its protective role in SD, NOS3 increases LV adverse remodeling after pressure overload in HFD-fed, insulin resistant mice. Interactions between NOS3 and mitochondria may be responsible for increased oxidative stress levels in HFD-fed WT mice hearts.

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