Diabetic patients with acute myocardial infarction are more likely to die than nondiabetic patients. In the present study we examined the effect of insulin resistance on myocardial ischemia tolerance. Hearts of rats, rendered insulin resistant by high-sucrose feeding, were subjected to ischemia/reperfusion ex vivo. Cardiac power of control hearts from chow-fed rats recovered to 93%, while insulin-resistant hearts recovered only to 80% (P<0.001 vs. control). Unexpectedly, impaired contractile recovery did not result from an impairment of glucose oxidation (576±36 vs. 593±42 nmol/min/g dry weight; not significant), but from a failure to increase and to sustain oxidation of the long-chain fatty acid oleate on reperfusion (1878±56 vs. 2070±67 nmol/min/g dry weight; P<0.05). This phenomenon was due to a reduced ability to transport oleate into mitochondria and associated with a 38-58% decrease in the mitochondrial uncoupling protein 3 (UCP3) levels. Contractile function was rescued by replacing oleate with a medium-chain fatty acid or by restoring UCP3 levels with 24 h of food withdrawal. Lastly, the knockdown of UCP3 in rat L6 myocytes also decreased oleate oxidation by 13-18% following ischemia. Together the results expose UCP3 as a critical regulator of long-chain fatty acid oxidation in the stressed heart postischemia and identify octanoate as an intervention by which myocardial metabolism can be manipulated to improve function of the insulin-resistant heart.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4046182PMC
http://dx.doi.org/10.1096/fj.13-234914DOI Listing

Publication Analysis

Top Keywords

decreased long-chain
4
long-chain fatty
4
fatty acid
4
acid oxidation
4
oxidation impairs
4
impairs postischemic
4
postischemic recovery
4
recovery insulin-resistant
4
insulin-resistant rat
4
rat heart
4

Similar Publications

The enduring pathogenicity of can be attributed to its lipid-rich cell wall, with mycolic acids (MAs) being a significant constituent. Different MAs' fluidity and structural adaptability within the bacterial cell envelope significantly influence their physicochemical properties, operational capabilities, and pathogenic potential. Therefore, an accurate conformational representation of various MAs in aqueous media can provide insights into their potential role within the intricate structure of the bacterial cell wall.

View Article and Find Full Text PDF

Molecular mechanism of long chain non coding RNA LINC00511 influencing breast cancer stem cells: Mechanism of VEGFR1 protein.

Int J Biol Macromol

January 2025

Department of Hepatobiliary Surgery, The First Affiliated Hospital, Jinan University, Guangzhou 510630, Guangdong, PR China; Department of Breast and Thyroid Surgery, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, PR China; Key Laloratory of Molecular Pathology in Tumors of Guangxi, Baise 533000, Guangxi, PR China; Department of Oncology-Pathology, Karolinska Institutet, Stockholm SE-17176, Sweden. Electronic address:

A comprehensive investigation into the mechanism of VEGFR1 protein in this process was undertaken. Lentivirus-mediated RNA interference was employed to inhibit the expression of LINC00511 in breast cancer cell lines, and changes in breast cancer stem cell markers, including CD44+/CD24-, were monitored using flow cytometry. Additionally, the interaction between VEGFR1 protein and LINC00511 and the activation of its downstream signaling pathway were investigated through co-immunoprecipitation (Co-IP) and Western blot techniques.

View Article and Find Full Text PDF

Spermidine enhances the heat tolerance of by promoting mitochondrial respiration driven by fatty acid β-oxidation.

Appl Environ Microbiol

January 2025

Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, China.

Unlabelled: High temperature is an unavoidable environmental stress that generally exerts detrimental effects on organisms and has widespread effects on metabolism. Spermidine is an important member of the polyamines family and is involved in a range of abiotic stress responses in plants. Mitochondria play an essential role in cellular homeostasis and are key components of the stress response.

View Article and Find Full Text PDF

Saturated fat in an evolutionary context.

Lipids Health Dis

January 2025

Institute of Health, Oslo New University College, Ullevålsveien 76, Oslo, 0454, Norway.

Evolutionary perspectives have yielded profound insights in health and medical sciences. A fundamental recognition is that modern diet and lifestyle practices are mismatched with the human physiological constitution, shaped over eons in response to environmental selective pressures. This Darwinian angle can help illuminate and resolve issues in nutrition, including the contentious issue of fat consumption.

View Article and Find Full Text PDF

Follicular ovarian cysts (FOCs) are prevalent reproductive disorders in both humans and animals, especially in livestock, where they cause economic losses by reducing fertility and productivity. FOCs are marked by a dominant follicle that fails to ovulate, disrupting the estrous cycle and reproductive efficiency. Previous studies indicate that the follicular fluid (FF) in cystic ovaries shows oxidative imbalance, affecting oocyte quality by altering glutathione peroxidase (GPX1) and selenium pathways.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!