Concentration-Dependent Effects of N-3 Long-Chain Fatty Acids on Na,K-ATPase Activity in Human Endothelial Cells

Regular use of fish oil supplements and course of cardiovascular diseases: prospective cohort study

Objective

To examine the effects of fish oil supplements on the clinical course of cardiovascular disease, from a healthy state to atrial fibrillation, major adverse cardiovascular events, and subsequently death.

Design

Prospective cohort study.

Setting

UK Biobank study, 1 January 2006 to 31 December 2010, with follow-up to 31 March 2021 (median follow-up 11.9 years).

Participants

415 737 participants, aged 40-69 years, enrolled in the UK Biobank study.

Main outcome measures

Incident cases of atrial fibrillation, major adverse cardiovascular events, and death, identified by linkage to hospital inpatient records and death registries. Role of fish oil supplements in different progressive stages of cardiovascular diseases, from healthy status (primary stage), to atrial fibrillation (secondary stage), major adverse cardiovascular events (tertiary stage), and death (end stage).

Results

Among 415 737 participants free of cardiovascular diseases, 18 367 patients with incident atrial fibrillation, 22 636 with major adverse cardiovascular events, and 22 140 deaths during follow-up were identified. Regular use of fish oil supplements had different roles in the transitions from healthy status to atrial fibrillation, to major adverse cardiovascular events, and then to death. For people without cardiovascular disease, hazard ratios were 1.13 (95% confidence interval 1.10 to 1.17) for the transition from healthy status to atrial fibrillation and 1.05 (1.00 to 1.11) from healthy status to stroke. For participants with a diagnosis of a known cardiovascular disease, regular use of fish oil supplements was beneficial for transitions from atrial fibrillation to major adverse cardiovascular events (hazard ratio 0.92, 0.87 to 0.98), atrial fibrillation to myocardial infarction (0.85, 0.76 to 0.96), and heart failure to death (0.91, 0.84 to 0.99).

Conclusions

Regular use of fish oil supplements might be a risk factor for atrial fibrillation and stroke among the general population but could be beneficial for progression of cardiovascular disease from atrial fibrillation to major adverse cardiovascular events, and from atrial fibrillation to death. Further studies are needed to determine the precise mechanisms for the development and prognosis of cardiovascular disease events with regular use of fish oil supplements.

Trichoderma harzianum Peptaibols Stimulate Plant Plasma Membrane H+-ATPase Activity

Because of their ability to promote growth, act as biopesticides, and improve abiotic stress tolerance, Trichoderma spp. have been used for plant seed coating. However, the mechanism for the promotion of plant growth remains unknown. In this study, we investigate the effect of fungal extracts on the plant plasma membrane (PM) H+-ATPase, which is essential for plant growth and often a target of plant-associated microbes. We show that Trichoderma harzianum extract increases H+-ATPase activity, and by fractionation and high-resolution mass spectrometry (MS), we identify the activating components trichorzin PA (tPA) II and tPA VI that belong to the class of peptaibols. Peptaibols are nonribosomal peptides that can integrate into membranes and form indiscriminate ion channels, which causes pesticidal activity. To further investigate peptaibol-mediated H+-ATPase activation, we compare the effect of tPA II and VI to that of the model peptaibol alamethicin (AlaM). We show that AlaM increases H+-ATPase turnover rates in a concentration-dependent manner, with a peak in activity measured at 31.25 μM, above which activity decreases. Using fluorescent probes and light scattering, we find that the AlaM-mediated increase in activity is not correlated to increased membrane fluidity or vesicle integrity, whereas the activity decrease at high AlaM concentrations is likely due to PM overloading of AlaM pores. Overall, our results suggest that the symbiosis of fungi and plants, specifically related to peptaibols, is a concentration-dependent balance, where peptaibols do not act only as biocontrol agents but also as plant growth stimulants.

Habitual fish oil supplementation and the risk of incident atrial fibrillation: findings from a large prospective longitudinal cohort study

AIMS

Mixed effects of fish oil supplementation on the risks of atrial fibrillation (AF) were observed in several large-scale randomized controlled trials. Whether this relationship would be modified by genetic AF risk, baseline cardiovascular disease (CVD) status and background oily fish consumption are unknown.

METHODS AND RESULTS

We included 468 665 participants without AF at baseline from the UK Biobank cohort. The association between fish oil supplementation and the AF risk was assessed in the study cohort and in several subgroups, including genetic AF predisposition, baseline CVD status, and background oily fish consumption. During a median follow-up of 11.1 years, fish oil users had a higher rate of incident AF (6.2% vs. 5.2%, adjusted hazard ratio of 1.10, and 95% confidence interval of 1.07, 1.13). Compared with non-users, fish oil users had a higher rate of incident AF in the low (3.7% vs. 3.0%, P= 0.02), intermediate (5.8% vs. 4.8%, P < 0.0001), and high (9.8% vs. 8.1%, P < 0.0001) genetic AF risk groups. In participants without CVD at baseline, fish oil users had a higher rate of incident AF (5.3% vs. 4.1%, P < 0.0001), which was not observed in participants with CVD at baseline (11.6% vs. 11.1%, P = 0.56), with significant interaction (P-interaction < 0.0001). The association between fish oil supplementation and the AF risk was not modified by background oily fish consumption (P-interaction = 0.62).

CONCLUSION

Habitual fish oil supplementation was associated with the risk of incident AF, regardless of genetic AF predisposition and background oily fish consumption. This association was observed only in individuals without CVD at baseline.

Highly Purified Eicosapentaenoic Acid Alleviates the Inflammatory Response and Oxidative Stress in Macrophages during Atherosclerosis via the miR-1a-3p/sFRP1/Wnt/PCP-JNK Pathway

Highly purified eicosapentaenoic acid (EPA) has shown great effects in the prevention of atherosclerosis. In a murine model, it significantly reduced plaque accumulation, lowered plasma lipid levels, and decreased inflammation levels, which was also observed in vitro. Using microRNA sequencing, we identified differentially expressed microRNAs, among which miR-1a-3p was selected for further validation. Overexpression of miR-1a-3p in RAW264.7 cells worsened lipid accumulation, increased oxidative stress, and exacerbated inflammatory responses whereas its downregulation produced the opposite results. Potential targets of miR-1a-3p were analyzed by prediction tools. Then, secreted frizzled-related protein 1 (sFRP1), an antagonist of the Wnt pathway, was confirmed as the target gene of miR-1a-3p by a dual-luciferase reporter assay. Further research showed that in macrophages, EPA influenced the activation of the Wnt/planar cell polarity-c-Jun N-terminal kinase (Wnt/PCP-JNK) axis, which is consistent with the phenomenon that miR-1a-3p has an impact on this same axis. Collectively, our findings suggest that EPA mitigates inflammatory responses and oxidative responses both in vivo and in vitro by targeting the miR-1a-3p/sFRP1/Wnt/PCP-JNK axis in macrophages, which may explain the cardioprotective role of EPA and promote the application of EPA in clinical practice.

Highly Purified Eicosapentaenoic Acid Alleviates the Inflammatory Response and Oxidative Stress in Macrophages during Atherosclerosis via the miR-1a-3p/sFRP1/Wnt/PCP-JNK Pathway

Highly purified eicosapentaenoic acid (EPA) has shown great effects in the prevention of atherosclerosis. In a murine model, it significantly reduced plaque accumulation, lowered plasma lipid levels, and decreased inflammation levels, which was also observed in vitro. Using microRNA sequencing, we identified differentially expressed microRNAs, among which miR-1a-3p was selected for further validation. Overexpression of miR-1a-3p in RAW264.7 cells worsened lipid accumulation, increased oxidative stress, and exacerbated inflammatory responses whereas its downregulation produced the opposite results. Potential targets of miR-1a-3p were analyzed by prediction tools. Then, secreted frizzled-related protein 1 (sFRP1), an antagonist of the Wnt pathway, was confirmed as the target gene of miR-1a-3p by a dual-luciferase reporter assay. Further research showed that in macrophages, EPA influenced the activation of the Wnt/planar cell polarity-c-Jun N-terminal kinase (Wnt/PCP-JNK) axis, which is consistent with the phenomenon that miR-1a-3p has an impact on this same axis. Collectively, our findings suggest that EPA mitigates inflammatory responses and oxidative responses both in vivo and in vitro by targeting the miR-1a-3p/sFRP1/Wnt/PCP-JNK axis in macrophages, which may explain the cardioprotective role of EPA and promote the application of EPA in clinical practice.

Rutin Improves Cardiac and Erythrocyte Membrane-Bound ATPase Activities in Male Rats Exposed to Cadmium Chloride and Lead Acetate

Cardiovascular diseases have been associated with cadmium (Cd) and lead (Pb). Impaired Ca²⁺ and Na⁺/K⁺-ATPase activities have also been linked to hemolytic and cardiovascular disorders. This study investigated the effect of rutin on Cd and/or Pb-induced cardiac and erythrocyte disorders in male rats. Twenty-five (25) male Wistar rats were treated as (n=5): Control, Pb (60 mg/kg, p.o), Cd (5 mg/kg, p.o), Pb + Cd, Rutin + Pb + Cd (50 mg/kg Rt, 60 mg/kg Pb, 5 mg/kg Cd, p.o). Plasma electrolyte and Ca²⁺- and Na⁺/K⁺-ATPase activities in the erythrocyte and heart of the rats were assayed. There was an increased and decreased activity of cardiac and erythrocyte Na⁺/K⁺-ATPase in Pb- (172%) and Cd- (33.7%) treated groups, respectively. However, rutin increased erythrocyte Na⁺/K⁺-ATPase activity in Cd + Pb when compared with Cd and Cd + Pb groups. Erythrocyte Ca²⁺-ATPase activity was decreased in the Pb (68%), Cd (68%) and Cd + Pb (55.3%) groups. Cardiac Na⁺/K⁺-ATPase activity was not altered in Pb and Cd groups while it decreased in Cd + Pb. Rutin increased the activity of the pump in Cd +Pb-treated rats compared to the Cd+Pb group. Therefore, rutin reversed cadmium- and lead-induced impaired cardiac and erythrocyte membrane Ca²⁺- and Na⁺/K⁺-ATPase activities. Graphical Abstract Dotted lines-decrease activity, curved lines-increased activity (created with BioRender.com ).

Chia seed (Salvia hispanica L.) consumption and lipid profile: a systematic review and meta-analysis

Chia (Salvia hispanica L.) is an annual herbaceous plant, originally from southern Mexico and northern Guatemala - nowadays grown all over the world. In recent years, there has been an increase in demand for plant foods with health-promoting properties, and chia is a main actor in this process due to its high nutritional and functional value and its chemical composition rich in PUFAs, mainly ω-3, as well as protein, dietary fiber, and bioactive compounds. Chia has been explored in different research models for health and the prevention of human diseases. Evidence has suggested potential for improving insulin resistance, disordered lipid profiles, glucose tolerance and even adiposity. The aim of this study was to evaluate the effect of consumption of chia seeds on the lipid profile, triglycerides, and serum ω-3 fatty acids in adults. This systematic review included all randomized controlled trials (parallel or crossover design) published up to August 2020 in the main databases Medline, Embase, Scopus, Web of Science, and Scielo. Two independent authors selected and extracted data from those articles. After the selection process, 10 clinical trials were included. Forest plots and summary tables were constructed to present data and sensitivity subgroup analyses were performed for some of the outcomes. The results showed that chia consumption suggests a protective effect on the lipid profile, decreasing TC (MD = -2.98, 95% CI = [-9.98; 4.02]), TG (MD = -14.09 mg dL-1, 95% CI = [-33.46; 5.28]), and LDL (MD = 2.07 mg dL-1; 95% CI = [-5.05; 9.19]) and increasing HDL (MD = -2.92 mg dL-1, 95% CI = [-5.91; 0.06]). Regarding serum fatty acids, chia reduced FFA and SFA and increased PUFAs, ALA, EPA, and LA. It has also reduced DHA while not changing DPA. The intake of chia appears to have a neutral or beneficial effect on some markers of the lipid and fatty acid profile.