Plant-derived polyphenols regulate expression of miRNA paralogs miR-103/107 and miR-122 and prevent diet-induced fatty liver disease in hyperlipidemic mice

BACKGROUND

MicroRNAs have the potential for clinical application. Probable modulation by plant-derived polyphenols might open preventive measures using simple dietary recommendations.

METHODS

We assessed the ability of continuous administration of high-dose polyphenols to modulate hepatic metabolism and microRNA expression in diet-induced fatty liver disease in commercially available hyperlipidemic mice using well-established and accepted procedures that included the development of new antibodies against modified quercetin.

RESULTS

Weight gain, liver steatosis, changes in the composition of liver tissue, and insulin resistance were all attenuated by the continuous administration of polyphenols. We also demonstrated that metabolites of polyphenols accumulate in immune cells and at the surface of hepatic lipid droplets indicating not only bioavailability but a direct likely action on liver cells. The addition of polyphenols also resulted in changes in the expression of miR-103, miR-107 and miR-122.

CONCLUSIONS

Polyphenols prevent fatty liver disease under these conditions. The differential expression of mRNAs and miRNAs was also associated with changes in lipid and glucose metabolism and with the activation of 5'-adenosine monophosphate-activated protein kinase, effects that are not necessarily connected. miRNAs function via different mechanisms and miRNA-mRNA interactions are difficult to ascertain with current knowledge. Further, cell models usually elicit contradictory results with those obtained in animal models.

GENERAL SIGNIFICANCE

Our data indicate that plant-derived polyphenols should be tested in humans as preventive rather than therapeutic agents in the regulation of hepatic fatty acid utilization. A multi-faceted mechanism of action is likely and the regulation of liver miRNA expression blaze new trails in further research.

Randomized clinical trial to assess the efficacy of a comprehensive programme of secondary prevention of cardiovascular disease in general practice: the PREseAP study

INTRODUCTION AND OBJECTIVES

To assess the efficacy of a comprehensive program of secondary prevention of cardiovascular disease in general practice.

METHODS

A cluster randomized clinical trial was carried out in a regular general practice setting. Male and female patients aged under 86 years with a diagnosis of ischemic heart disease, stroke or peripheral artery disease were recruited between January 2004 and May 2005. Study participants were seen at 42 health centers throughout the whole of Spain. The primary endpoint was the combination of all-cause mortality and hospital cardiovascular readmission at 3-year follow-up.

RESULTS

In total, 1224 patients were recruited: 624 in the intervention group and 600 in the control group. The primary endpoint was observed in 29.9% (95% confidence interval [CI], 25.5-34.8%) in the intervention group and 25.6% (22.3-29.2%) in the control group (P=.15). At the end of follow-up, 8.5% (6.3-11.3%) in the intervention group and 11% (7.4-16%) in the control group were smokers (P=.07). The mean waist circumference of patients in the intervention and control groups was 100.44 cm (95% CI, 98.97-101.91 cm) and 102.58 cm (95% CI, 100.96-104.21 cm), respectively (P=.07). Overall, 20.9% (15.6-27.7%) of patients in the intervention group and 29.6% (23.9-36.1%) in the control group suffered from anxiety (P=.05), and 29.6% (22.4-37.9%) in the intervention group and 41.4% (35.8-47.3%) in the control group had depression (P=.02).

CONCLUSIONS

A comprehensive program of secondary prevention of cardiovascular disease in general practice was not effective in reducing cardiovascular morbidity and mortality. However, some factors associated with a healthy lifestyle were improved and anxiety and depression were reduced.

[Evaluation of the efficacy of a comprehensive programme of secondary prevention of cardiovascular disease in primary care: the PREseAP Study]

OBJECTIVES

To assess the efficacy of a comprehensive secondary prevention programme to reduce morbidity and mortality in patients who have suffered a cardiovascular (CV) event; to control CV risk factors and prophylactic treatment in order to prevent recurrence; and to improve the quality of life of patients with cardiovascular disease.

DESIGN

Randomised, pragmatic, open clinical trial in primary care.

SETTING

A total of 42 primary care centres of 8 different areas in Spain.

PARTICIPANTS

Men and women below 86 years old, diagnosed with coronary disease and/or stroke and/or peripheral vascular disease in the preceding year, and who have no serious or terminal disease.

INTERVENTION

Primary care centres will be randomised to following usual care (control group), or to following a comprehensive programme of secondary prevention (intervention group).

MAIN MEASUREMENTS

Cardiovascular fatal events, cardiovascular non-fatal events, total mortality and health-related quality of life (SF-36).

A novel locus for non-syndromic sensorineural deafness (DFN6) maps to chromosome Xp22

Non-syndromic X-linked deafness is highly heterogeneous. At least five different clinical forms have been described, but only two loci have been mapped. Here we report a Spanish family affected by a previously undescribed X-linked form of hearing impairment. Deafness is non-syndromic, sensorineural, and progressive. In affected males, the auditory impairment is first detected at school age, affecting mainly the high frequencies. Later it evolves to become severe to profound, involving all frequencies for adulthood. Carrier females manifest a moderate hearing impairment in the high frequencies, with the onset delayed to the fourth decade of life. Deafness was assumed to be X-linked dominant, with incomplete penetrance and variable expressivity in carrier females. The family was genotyped for a set of microsatellite markers evenly spaced at intervals of about 10 cM. We found evidence of linkage to markers in the Xp22 region (maximum lod score of 5.30 at theta = 0.000 for DXS8036 and for DXS8022). The position of the novel deafness locus (DFN6) was refined by haplotype analysis. Mapping of the breakpoints in two critical recombinants allowed us to define an interval for DFN6, delimited by DXS7108 on the distal side and by DXS7105 on the proximal side, and spanning a genetic distance of about 15 cM.