Omega-3 polyunsaturated fatty acids: Their potential role in blood pressure prevention and management

The effect of omega-3 supplements on the serum levels of ACE/ACE2 ratio as a potential key in cardiovascular disease: A randomized clinical trial in participants with vitamin D deficiency

Objective

The aim of this randomized controlled clinical trial was to determine the effect of the omega-3 fatty acid supplementations 300 mg per day for 8 weeks on the serum levels of ACE/ACE2 ratio in Jordanian participants with vitamin D deficiency (VDD).

Methods

The physical and clinical characteristic of individuals in both intervention and control randomized controlled clinical trial were measured and analyzed. The comparisons between the two groups and the changes in each group before and after taking omega-3 doses were studied through independent t test and paired t test, respectively. Possible factors that have a role in the changes were determined by multivariate stepwise regression. Follow-up period lasted 10 weeks.

Results

The sample consisted of 82 participants with VDD and a mean age of 37.85 ± 9.85 years. Omega-3 Supplements resulted in a significant decrease in serum ACE levels, ACE/ACE2 ratio and serum 25-hydroxy vitamin D (25OHD). While the change in serum ACE2 levels and serum triglycerides levels were insignificant. Also, a significant increase in serum LDL levels were observed.

Conclusion

It is possible that taking high doses of omega-3 fatty acid supplementations have positive effects on the heart and circulatory system and could protect from COVID-19 or decrease disease severity, in connection with a decrease in the ACE/ACE 2 ratio. On the other hand, omega-3 supplement may have negative effect on cardiovascular system due to the significant increase in serum LDL levels.

Long Chain N3-PUFA Decreases ACE2 Protein Levels and Prevents SARS-CoV-2 Cell Entry

Angiotensin-converting enzyme 2 (ACE2) is a target of interest for both COVID-19 and cardiovascular disease management. Even though lower ACE2 levels may be beneficial in SARS-CoV-2 infectivity, maintaining the ACE1/ACE2 balance is also crucial for cardiovascular health. So far, reports describing conditions capable of altering ACE2 protein levels, especially via dietary components, are limited. In this study, the effects of omega-3 polyunsaturated fatty acids (n3-PUFA) on the protein levels of ACE1 and ACE2 in rodent tissues, human endothelial and kidney cell lines, and human plasma were examined. The ability of n3-PUFA to affect the entry of the SARS-CoV-2 pseudovirus into cells was also tested. Docosahexaenoic acid (DHA), and in some cases eicosapentaenoic acid (EPA), but not α-linoleic acid (ALA), reduced both ACE1 and ACE2 (non-glycosylated p100 and glycosylated p130 forms) in the heart, aorta, and kidneys of obese rats, as well as in human EA.hy926 endothelial and HEK293 kidney cells. Dietary supplementation with either DHA or ALA had no effect on plasma soluble ACE2 levels in humans. However, treatment of HEK293 cells with 80 and 125 µM DHA for 16 h inhibited the entry of the SARS-CoV-2 pseudovirus. These results strongly suggest that DHA treatment may reduce the ability of SARS-CoV-2 to infect cells via a mechanism involving a decrease in the absolute level of ACE2 protein as well as its glycosylation. Our findings warrant further evaluation of long-chain n3-PUFA supplements as a novel option for restricting SARS-CoV-2 infectivity in the general population.

Long COVID and long chain fatty acids (LCFAs): Psychoneuroimmunity implication of omega-3 LCFAs in delayed consequences of COVID-19

The global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the lasting pandemic of coronavirus disease 2019 (COVID-19) and the post-acute phase sequelae of heterogeneous negative impacts in multiple systems known as the "long COVID." The mechanisms of neuropsychiatric complications of long COVID are multifactorial, including long-term tissue damages from direct CNS viral involvement, unresolved systemic inflammation and oxidative stress, maladaptation of the renin-angiotensin-aldosterone system and coagulation system, dysregulated immunity, the dysfunction of neurotransmitters and hypothalamus-pituitaryadrenal (HPA) axis, and the psychosocial stress imposed by societal changes in response to this pandemic. The strength of safety, well-acceptance, and accumulating scientific evidence has now afforded nutritional medicine a place in the mainstream of neuropsychiatric intervention and prophylaxis. Long chain omega-3 polyunsaturated fatty acids (omega-3 or n-3 PUFAs) might have favorable effects on immunity, inflammation, oxidative stress and psychoneuroimmunity at different stages of SARS-CoV-2 infection. Omega-3 PUFAs, particularly EPA, have shown effects in treating mood and neurocognitive disorders by reducing pro-inflammatory cytokines, altering the HPA axis, and modulating neurotransmission via lipid rafts. In addition, omega-3 PUFAs and their metabolites, including specialized pro-resolvin mediators, accelerate the process of cleansing chronic inflammation and restoring tissue homeostasis, and therefore offer a promising strategy for Long COVID. In this article, we explore in a systematic review the putative molecular mechanisms by which omega-3 PUFAs and their metabolites counteract the negative effects of long COVID on the brain, behavior, and immunity.

Chia seed (Salvia hispanica L.) supplementation to the diet of adults with type 2 diabetes improved systolic blood pressure: A randomized controlled trial

BACKGROUND

Functional food ingredients, such as dietary fiber, long-chain polyunsaturated fatty acids, and high-quality protein, have been shown to help control blood glucose concentration and lower high blood pressure (BP), as well as improving other cardiovascular disease risk factors. However, little research has assessed the impacts of consuming chia seeds, which are rich in these nutrients, on metabolic and physiological outcomes, and results are conflicting.

AIM

The study aimed to investigate the possible effects of chia seeds on fasting blood glucose, insulin, glycated hemoglobin, BP, lipid profile, body weight, and the inflammatory marker - high-sensitivity C-reactive protein - in people with type 2 diabetes (T2DM).

METHODS

Adults with T2DM (n = 42) were randomly assigned equally to the chia seed group, which consumed 40 g/day chia seeds for 12 weeks, or a control group, which did not consume any supplement. Blood samples were collected at baseline and after a 12-week intervention period to assess the study outcomes, such as glycemic control, BP, cardiovascular risk parameters including lipid profile, inflammatory marker, and body weight.

RESULTS

Adjusted for gender and baseline values, the chia seed group had systolic BP (SBP) significantly reduced compared to control [t (1) = 2.867, p = 0.007, η ² _p = 0.174]. No differences were observed in any other parameter tested in the chia seed or control group.

CONCLUSIONS

People with T2DM and hypertension, maintaining usual dietary consumption, physical activity pattern, and medications, had significantly reduced SBP compared to the control group when having consumed 40 g/d of chia seeds for 12 weeks.

The association of dietary patterns and cardiorespiratory fitness: A systematic review

AIMS

In comparison to the traditional risk factors of cardiovascular diseases, little is known about the interaction between diet and cardiorespiratory fitness (CRF). The present systematic review aimed to provide comprehensive evidence regarding the relationship between the dietary patterns (DPs) with CRF in both children and adults.

DATA SYNTHESIS

Databases of PubMed, Scopus, and Web of Science were searched from inception up to December 2019. All observational studies that had extracted DPs using a posteriori and/or a priori methods, as well as had assessed CRF as the outcome, were eligible for inclusion in the review. Eleven studies (1 longitudinal and 10 cross-sectional studies) comprising a total of 198,271 subjects were included. There was considerable heterogeneity between studies in terms of the extracted DPs, their food items as well as the statistical reporting outcomes; which all made comparisons between the studies difficult. Despite some inconsistent results, overall there was a positive association between the DPs that were highly loaded with fruits and vegetables, as well as closer adherence to the high-quality diets particularly the Mediterranean diet, with higher values of CRF. While, an inverse association was found for unhealthy DPs that were generally characterized by a high intake of refined grains, sweets, meats, processed foods, and high-fat dairy products.

CONCLUSION

Overall, the evidence indicates the high-quality diets that are highlighted in the national dietary guidelines are associated with an optimal CRF. However, these findings should be confirmed by rigorous prospective and interventional studies.

Protection of cardiac cell-to-cell coupling attenuate myocardial remodeling and proarrhythmia induced by hypertension

Gap junction connexin channels are important determinants of myocardial conduction and synchronization that is crucial for coordinated heart function. One of the main risk factors for cardiovascular events that results in heart attack, congestive heart failure, stroke as well as sudden arrhythmic death is hypertension. Mislocalization and/or dysfunction of specific connexin-43 channels due to hypertension-induced myocardial remodeling have been implicated in the occurrence of life-threatening arrhythmias and heart failure in both, humans as well as experimental animals. Recent studies suggest that down-regulation of myocardial connexin-43, its abnormal distribution and/or phosphorylation might be implicated in this process. On the other hand, treatment of hypertensive animals with cardioprotective drugs (e.g. statins) or supplementation with non-pharmacological compounds, such as melatonin, omega-3 fatty acids and red palm oil protects from lethal arrhythmias. The antiarrhythmic effects are attributed to the attenuation of myocardial connexin-43 abnormalities associated with preservation of myocardial architecture and improvement of cardiac conduction. Findings uncover novel mechanisms of cardioprotective (antihypertensive and antiarrhythmic) effects of compounds that are used in clinical settings. Well-designed trials are needed to explore the antiarrhythmic potential of these compounds in patients suffering from hypertension.

Modulation of Systemic and Aortic Nitric Oxide by Melatonin and n-3 Polyunsaturated Fatty Acids in Isoproterenol Affected Spontaneously Hypertensive and Normotensive Wistar Rats

We aimed to explore the effects of melatonin and n-3 polyunsaturated fatty acids (PUFA) supplementation on plasma and aortic nitric oxide (NO) levels in isoproterenol (Iso) affected spontaneously hypertensive (SHR) and Wistar rats. Untreated control rats were compared with Iso injected (118 mg/kg, s.c.) rats, and Iso injected plus supplemented with melatonin (10 mg/kg, p.o.) or PUFA (1.68 g/kg, p.o.) for two months. Plasma and aortic basal, L-NAME inhibited, adrenaline and acetylcholine stimulated NO were determined using Griess method. Plasma NO levels were lower in SHR versus Wistar rats. Iso decreased NO in Wistar while not in SHR. PUFA but not melatonin intake of Iso treated SHR increased plasma NO along with a decrease in systolic blood pressure. Basal aortic NO level was higher in SHR than Wistar rats and not altered by Iso. Intake of melatonin increased but PUFA decreased basal NO levels in Wistar+Iso and did not affect in SHR+Iso rats. Acetylcholine and adrenaline induced aortic NO release was significantly increased in Wistar+Iso but not SHR+Iso group. Melatonin intake increased Ach induced aortic NO in Wistar+Iso and SHR+Iso groups, whereas there was no effect of PUFA intake. Findings suggest that PUFA modulates plasma and melatonin aortic NO levels of isoproterenol affected rats in a strain-dependent manner.

Transcriptome-based identification of new anti-inflammatory and vasodilating properties of the n-3 fatty acid docosahexaenoic acid in vascular endothelial cell under proinflammatory conditions [corrected]

Scope

High intakes of n-3 fatty acids exert anti-inflammatory effects and cardiovascular protection, but the underlying molecular basis is incompletely defined. By genome-wide analysis we searched for novel effects of docosahexaenoic acid (DHA) on gene expression and pathways in human vascular endothelium under pro-inflammatory conditions.

Methods and Results

Human umbilical vein endothelial cells were treated with DHA and then stimulated with interleukin(IL)-1β. Total RNA was extracted, and gene expression examined by DNA microarray. DHA alone altered the expression of 188 genes, decreasing 92 and increasing 96. IL-1β changed the expression of 2031 genes, decreasing 997 and increasing 1034. Treatment with DHA before stimulation significantly affected the expression of 116 IL-1β-deregulated genes, counter-regulating the expression of 55 genes among those decreased and of 61 among those increased. Functional and network analyses identified immunological, inflammatory and metabolic pathways as the most affected. Newly identified DHA-regulated genes are involved in stemness, cellular growth, cardiovascular system function and cancer, and included cytochrome p450 4F2(CYP4F2), transforming growth factor(TGF)-β2, Cluster of Differentiation (CD)47, caspase recruitment domain(CARD)11 and phosphodiesterase(PDE)5α.

Conclusions

Endothelial exposure to DHA regulates novel genes and related pathways. Such unbiased identification should increase our understanding of mechanisms by which n-3 fatty acids affect human diseases.