[Cholesterol controversy: cutoff point of low-density lipoprotein cholesterol level in Guidelines by Japan Atherosclerosis Society]

Association of equol producing status with aortic calcification in middle-aged Japanese men: The ERA JUMP study

BACKGROUND

Equol, an isoflavone (ISF)-derived metabolite by the gut microbiome in certain individuals termed as equol-producers, might be the key anti-atherogenic component of ISFs. Our objective was to determine the association between equol-producing status and aortic atherosclerosis assessed as aortic calcification (AC).

METHODS

This population-based study of 302 Japanese men aged 40-49, free of cardiovascular disease, examined serum levels of equol and ISFs, AC in the entire aorta by electron-beam computed tomography with Agatston method, and cardiovascular risk factors. We defined equol-producers as individuals with serum levels of equol ≥20 nM and prevalent AC as an AC score ≥ 10. We analyzed the association between equol-producing status and AC using Tobit and logistic regressions. We performed age-stratified analyses since age was a significant effect-modifier.

RESULTS

The 60th to 90th percentile AC scores were 4 to 243 in equol-producers and 15 to 444 in non-producers, respectively. Overall, equol-producers (41% of the sample) had lower AC scores (-209, [95% confidence interval (CI): -455, 36]) and odds of AC (odds ratio (OR): 0.7 [95% CI: 0.4, 1.3]), although not statistically significant, compared to non-producers after controlling for cardiovascular risk factors. Among men aged 46-49, equol-producers had significantly lower AC scores (-428 [95% CI: -827, -29]). Furthermore, there were null associations between serum levels of ISFs and both AC score and the odds of AC.

CONCLUSION

In middle-aged Japanese men, equol-producers had a non-significantly lower burden of aortic atherosclerosis than non-producers whereas ISFs had a null association. Studies with larger sample sizes in both sexes are warranted.

Fistular onion stalk extract exhibits anti-atherosclerotic effects in rats

Fistular onion stalk is used as a traditional herbal medicine, and its extract exhibits certain beneficial effects on cardiovascular disease. In this study, the effects of fistular onion stalk extract on the pathological features, circulating inflammatory cytokines, local renin-angiotensin-aldosterone system (RAAS) and signaling pathway activities were examined using an in vivo model of atherosclerosis. Atherosclerosis of the aorta was induced by loading Sprague Dawley rats with a high-fat diet and vitamin D₂. Fistular onion stalk extract administration began five weeks after the induction of atherosclerosis and continued for 12 weeks. Rats treated with fistular onion stalk extract showed a significant reduction in the pathological region compared with the vehicle-treated controls. Inhibition of atherosclerosis was associated with preservation of the vascular wall and immune cell infiltration. The extract also reduced the levels of the local inflammatory cytokines interleukin (IL)-1β, IL-6, monocyte chemoattractant protein-1 and tumor necrosis factor-α. Furthermore, the extract downregulated the local activity of the RAAS. In addition, extract treatment inhibited several inflammatory signaling pathways by preventing phosphorylation, including the nuclear factor κB, Janus kinase/signal transducers and activators of transcription and mitogen-activated protein kinase pathways. These data indicate that fistular onion stalk extract may be useful for the attenuation of atherosclerosis, and the mechanism includes the regulation of the local inflammatory response.

Pharmacophore generation and atom-based 3D-QSAR of N-iso-propyl pyrrole-based derivatives as HMG-CoA reductase inhibitors

Background

Coronary heart disease continues to be the leading cause of mortality and a significant cause of morbidity and account for nearly 30% of all deaths each year worldwide. High levels of cholesterol are an important risk factor for coronary heart disease. The blockage of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity by small molecule inhibitors has been shown to inhibit hypercholesterolemia. Herein, we describe the development of effective and robust pharmacophore model and the structure–activity relationship studies of 43N-iso-propyl pyrrole-based derivatives previously reported for HMG-CoA reductase inhibition.

Results

A 5-point pharmacophore model was developed and the generated pharmacophore model was used to derive a predictive atom-based 3D quantitative structure–activity relationship analysis (3D-QSAR) model for the studied dataset. The obtained 3D-QSAR model has an excellent correlation coefficient value (r² = 0.96) along with good statistical significance as shown by high Fisher ratio (F = 143.2). The model also exhibited good predictive power confirmed by the high value of cross validated correlation coefficient (q² = 0.672). Further, pharmacophoric model was employed for virtual screening to identify four potential HMG-CoA reductase inhibitors.

Conclusions

The QSAR model suggests that electron-withdrawing character is crucial for the HMG-CoA reductase inhibitory activity. In addition to the electron-withdrawing character, hydrogen bond--donating groups, hydrophobic and negative ionic groups positively contribute to the HMG-CoA reductase inhibition. These findings provide a set of guidelines for designing compounds with better HMG-CoA reductase inhibitory potential.