Lipid Emulsions Containing Medium Chain Triacylglycerols Blunt Bradykinin-Induced Endothelium-Dependent Relaxation in Porcine Coronary Artery Rings

SGLT2 expression in human vasculature and heart correlates with low-grade inflammation and causes eNOS-NO/ROS imbalance

AIMS

Sodium-glucose co-transporter 2 inhibitors (SGLT2i) show a cardioprotective effect in heart failure and myocardial infarction, pathologies often associated with low-grade inflammation. This cross-sectional study aims to investigate whether low-grade inflammation regulates SGLT2 expression and function in human vasculature, heart, and endothelial cells (ECs).

METHODS AND RESULTS

Human internal thoracic artery (ITA), left ventricle (LV) specimens, and cultured porcine coronary artery ECs were used. Expression of target molecules was assessed using RT-qPCR, western blot analysis, and immunofluorescence staining, and the generation of reactive oxygen species (ROS) and nitric oxide (NO) using fluorescent probes. The function of SGLT2 was investigated using empagliflozin and SGLT1 or 2 siRNA. SGLT2 mRNA and protein levels in ITA and LV specimens were correlated with the level of low-grade inflammation, markers of the angiotensin system, and EC activation. SGLT2 staining was observed in the ITA endothelium and smooth muscle, the coronary microcirculation, and cardiomyocytes. Elevated ROS formation in high SGLT2-expressing specimens was reduced by inhibition of the angiotensin system, SGLT2, and TNF-α. Exposure of ECs to IL-1ß, IL-6, and TNF-α led to an increase in SGLT1 and SGLT2 mRNA and protein expression, up-regulation of components of the angiotensin system, enhanced ROS and decreased NO formation, and activation of NF-κB. The stimulatory effect of TNF-α was prevented by N-acetylcysteine and inhibition of the angiotensin system, SGLT2 but not SGLT1, and NF-κB.

CONCLUSION

Low-grade inflammation is closely associated with SGLT2 expression in human vasculature and heart, and this response contributes to a feedforward mechanism with the AT1R/NADPH oxidase pathway to cause eNOS-NO/ROS imbalance.

Biological and Clinical Aspects of an Olive Oil-Based Lipid Emulsion-A Review

Intravenous lipid emulsions (ILEs) have been an integral component of parenteral nutrition for more than 50 years. Numerous formulations are available and are based on vegetable (soybean, olive, coconut) and animal (fish) oils. Therefore, each of these formulations has a unique fatty acid composition that offers both benefits and limitations. As clinical experience and our understanding of the effects of fatty acids on various physiological processes has grown, there is evidence to suggest that some ILEs may have benefits compared with others. Current evidence suggests that olive oil-based ILE may preserve immune, hepatobiliary, and endothelial cell function, and may reduce lipid peroxidation and plasma lipid levels. There is good evidence from a large randomized controlled study to support a benefit of olive oil-based ILE over soybean oil-based ILE on reducing infections in critically ill patients. At present there is limited evidence to demonstrate a benefit of olive oil-based ILE over other ILEs on glucose metabolism, and few data exist to demonstrate a benefit on clinical outcomes such as hospital or intensive care unit stay, duration of mechanical ventilation, or mortality. We review the current research and clinical evidence supporting the potential positive biological and clinical aspects of olive oil-based ILE and conclude that olive oil-based ILE is well tolerated and provides effective nutritional support to various PN-requiring patient populations. Olive oil-based ILE appears to support the innate immune system, is associated with fewer infections, induces less lipid peroxidation, and is not associated with increased hepatobiliary or lipid disturbances. These data would suggest that olive oil-based ILE is a valuable option in various PN-requiring patient populations.

Olive Fruit Blends Modulate Lipid-Sensing Nuclear Receptor PPARγ, Cell Survival, and Oxidative Stress Response in Human Osteoblast Cells

OBJECTIVE

The aim of the present study was to investigate how different extravirgin olive oils (EVOOs), obtained by blending Olea europea cultivars, could influence the cell growth, the response to inflammatory stimuli, and oxidative stress in a culture of the osteosarcoma cell line Saos-2.

METHODS

Three different extravirgin olive oils were physicochemically characterized, determining the free acidity, the oxidation status, the polyphenols content, and the antioxidative activity. Moreover, the effects on Saos-2 cell culture were determined, studying the mRNA expression level by real-time polymerase chain reaction (PCR) assays and the antioxidative activity using fluorescent probes.

RESULTS

The cultivars used in the south of Italy, yield extravirgin oils with different amount of fatty acids and polyphenols, which counteract induction of proinflammatory cytokines and regulate free radical production in hydrogen peroxide-stimulated cells. In vitro analysis using the human osteoblast cell line Saos-2 showed that the addition of oils to cell culture simulated a hypoxic stress followed by a reoxygenation period, during which the antioxidant activity of extravirgin olive oils protected cells from oxidative damages. On the other hand, the mRNA expression levels of factors involved in inflammatory processes, cell growth recovery, and antioxidant response, as heme oxygenase-1, were differently stimulated by EVOOs. Moreover, peroxisome proliferator activated receptor γ (PPARγ) was differently modulated by EVOOs.

CONCLUSION

These findings show that the blending of different extravirgin olive oil can impact an osteoblast cell line, in particular regarding cell growth recovery and oxidative stress.