Transient reduction in coronary perfusion pressure in the isolated mouse heart increases microvascular resistance (paradoxical vasoconstriction) by an endothelium-mediated mechanism. To assess the presence and extent of paradoxical vasoconstriction in hearts from normal and diabetic rats and to determine whether increased heme oxygenase (HO)-1 expression and HO activity, using cobalt protoporphyrin (CoPP), attenuates coronary microvascular response, male Wistar rats were rendered diabetic with nicotinamide/streptozotocin for 2 wk and either CoPP or vehicle was administered by intraperitoneal injection weekly for 3 wk (0.5 mg/100 g body wt). The isolated beating nonworking heart was submitted to transient low perfusion pressure (20 mmHg), and coronary resistance (CR) was measured. During low perfusion pressure, CR increased and was associated with increased lactate release. In diabetic rats, CR was higher, HO-1 expression and endothelial nitric oxide synthase were downregulated, and inducible nitric oxide synthase and O(2)(-) were upregulated. After 3 wk of CoPP treatment, HO activity was significantly increased in the heart. Upregulation of HO-1 expression and HO activity by CoPP resulted in the abolition of paradoxical vasoconstriction and a reduction in oxidative ischemic damage. In addition, there was a marked increase in serum adiponectin. Elevated HO-1 expression was associated with increased expression of cardiac endothelial nitric oxide synthase, B-cell leukemia/lymphoma extra long, and phospho activator protein kinase levels and decreased levels of inducible nitric oxide synthase and malondialdehyde. These results suggest a critical role for HO-1 in microvascular tone control and myocardial protection during ischemia in both normal and mildly diabetic rats through the modulation of constitutive and inducible nitric oxide synthase expression and activity, and an increase in serum adiponectin.

Download full-text PDF

Source
http://dx.doi.org/10.1152/ajpheart.00826.2007DOI Listing

Publication Analysis

Top Keywords

nitric oxide
20
oxide synthase
20
diabetic rats
16
ho-1 expression
16
perfusion pressure
12
paradoxical vasoconstriction
12
expression activity
12
inducible nitric
12
mildly diabetic
8
low perfusion
8

Similar Publications

To design a multifunctional nanozyme hydrogel with antibacterial, photo-responsive nitric oxide-releasing, and antioxidative properties for promoting the healing of infected wounds. We first developed ultra-small silver nanoparticles (NPs)-decorated sodium nitroprusside-doped Prussian blue (SNPB) NPs, referred to as SNPB@Ag NPs, which served as a multifunctional nanozyme. Subsequently, this nanozyme, together with geniposide (GE), was incorporated into a thermo-sensitive hydrogel, formulated from Poloxamer 407 and carboxymethyl chitosan, creating a novel antibacterial wound dressing designated as GE/SNPB@Ag hydrogel.

View Article and Find Full Text PDF

Background: Obesity is a risk factor for developing cardiovascular diseases (CVDs) by impairing normal vascular function. Natural products are gaining momentum in the clinical setting due to their high efficacy and low toxicity. extract (CFE) has been shown to control appetite and promote weight loss; however, its effect on vascular function remains poorly understood.

View Article and Find Full Text PDF

Biofilms are a well-known multifactorial virulence factor with a pivotal role in chronic bacterial infections. Their pathogenicity is determined by the combination of strain-specific mechanisms of virulence and the biofilm extracellular matrix (ECM) protecting the bacteria from the host immune defense and the action of antibacterials. The successful antibiofilm agents should combine antibacterial activity and good biocompatibility with the capacity to penetrate through the ECM.

View Article and Find Full Text PDF

Harnessing the Power of Our Immune System: The Antimicrobial and Antibiofilm Properties of Nitric Oxide.

Microorganisms

December 2024

Advanced Wound Care Research & Development, Convatec, Deeside Industrial Park, Deeside CH5 2NU, UK.

Nitric oxide (NO) is a free radical of the human innate immune response to invading pathogens. NO, produced by nitric oxide synthases (NOSs), is used by the immune system to kill microorganisms encapsulated within phagosomes via protein and DNA disruption. Owing to its ability to disperse biofilm-bound microorganisms, penetrate the biofilm matrix, and act as a signal molecule, NO may also be effective as an antibiofilm agent.

View Article and Find Full Text PDF

Our preliminary data using bone marrow-derived macrophages (BMDMs) collected from ICR mice treated with anti-sirtuin (anti-SIRT) 1 antibody showed that uptake was significantly attenuated. We then further investigated the effect of an inhibitor of SIRT1/2, cambinol, in the progression of . The in vitro results using RAW264.

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!