Changes in hepatic lipogenic and oxidative enzymes and glucose homeostasis induced by an acetyl-l-carnitine and nicotinamide treatment in dyslipidaemic insulin-resistant rats

Severe hypertriglyceridemia in Norway: prevalence, clinical and genetic characteristics

BACKGROUND

There is a lack of comprehensive patient-datasets regarding prevalence of severe hypertriglyceridemia (sHTG; triglycerides ≥10 mmol/L), frequency of co-morbidities, gene mutations, and gene characterization in sHTG. Using large surveys combined with detailed analysis of sub-cohorts of sHTG patients, we here sought to address these issues.

METHODS

We used data from several large Norwegian surveys that included 681,990 subjects, to estimate the prevalence. Sixty-five sHTG patients were investigated to obtain clinical profiles and candidate disease genes. We obtained peripheral blood mononuclear cells (PBMC) from six male patients and nine healthy controls and examined expression of mRNAs involved in lipid metabolism.

RESULTS

The prevalence of sHTG was 0.13 (95% CI 0.12-0.14)%, and highest in men aged 40-49 years and in women 60-69 years. Among the 65 sHTG patients, a possible genetic cause was found in four and 11 had experienced acute pancreatitis. The mRNA expression levels of carnitine palmitoyltransferase (CPT)-1A, CPT2, and hormone-sensitive lipase, were significantly higher in patients compared to controls, whereas those of ATP-binding cassette, sub-family G, member 1 were significantly lower.

CONCLUSIONS

In Norway, sHTG is present in 0.1%, carries considerable co-morbidity and is associated with an imbalance of genes involved in lipid metabolism, all potentially contributing to increased cardiovascular morbidity in sHTG.

Effect of insulin-resistance on circulating and adipose tissue MMP-2 and MMP-9 activity in rats fed a sucrose-rich diet

BACKGROUND AND AIM

Adipose tissue produces different metalloproteinases (MMPs), involved in adipogenesis and angiogenesis. Different studies have shown that in obesity the behavior of different MMPs may be altered. However there are scarce data about the effect of insulin-resistance (IR) on MMP-2 and MMP-9 activity in adipose tissue. Our aim was to determine whether sucrose induced IR modifies MMP-2 and MMP-9 behavior in expanded visceral adipose tissue and the contribution of this tissue to circulating activity of these gelatinases.

METHODS AND RESULTS

Male Wistar rats were fed with standard diet (Control) or standard diet plus 30% sucrose in the drinking water throughout 12 weeks (SRD). In epididymal adipose tissue vascular density, size and adipocyte density, PPARγ expression and MMP-2 and -9 were measured. Adipose tissue from SRD presented higher adipocyte size (6.32 ± 8.71 vs 4.33 ± 2.17 × 10(3) μm(2), p = 0.001) lower adipocyte density (164 (130-173) vs 190 (170-225) number/mm(2), p = 0.046) and lower vascular density (16.2 (12.8-23.5) vs 28.1 (22.3-46.5) blood vessels/mm(2), p = 0.002) than Control. MMP-2 and MMP-9 activity was decreased in SRD (1.93 ± 0.7 vs 3.92 ± 0.9 relative units, p = 0.048 and 1.80 ± 0.8 vs 5.13 ± 1.7 relative units, p = 0.004 respectively) in accordance with lower protein expression (0.35 ± 0.20 vs 2.71 ± 0.48 relative units, p = 0.004 and 1.12 ± 0.21 vs 1.52 ± 0.05 relative units, p = 0.036 respectively). There were no differences in PPARγ expression between groups.

CONCLUSION

Insulin resistance induced by SRD decreases MMP-2 and MMP-9 activity in adipose tissue which would not represent an important source for circulating MMP-2 and -9. In this state of IR, PPARγ would not be involved in the negative regulation of adipose tissue gelatinases.