Serum levels of Lp(a) are related to waist circumference in NAFLD patients with low prevalence of co-morbidities

BACKGROUND

Novel evidence suggests a relationship between circulating Lp(a) levels and the presence of cardiovascular events independently from the cardio-metabolic profile.

METHODS AND RESULTS

The purpose of this study was to investigate serum Lp(a) concentrations in relation to carotid intima-media thickness (IMT), anthropometric measures, lipid profile, assessment of insulin resistance, and other parameters conventionally used to predict CVD risk, in obese patients suffering from hepatic steatosis (HS), the well-known nonalcoholic fatty liver disease (NAFLD). Evidencing the key-points of this research, firstly, serum Lp(a) concentrations were not associated with carotid IMT in this selected population or, consequently, with early atherosclerosis, at least as evaluated by IMT. Secondly, carotid IMT was not predicted by HS severity, as evaluated by ultrasound. Finally, in the adjusted model, Lp(a) was positively predicted by waist circumference (WC) (β = 0.25, t = 2.3, p = 0.02) and negatively by central adiposity, assessed as visceral adipose tissue at US (β = -0.33, t = -3.0, p = 0.003).

CONCLUSION

Serum Lp(a) values may not play a direct role in increasing IMT, albeit associated with WC.

Is serum Interleukin-17 associated with early atherosclerosis in obese patients?

Atherosclerosis is a chronic inflammatory process of the vessel walls, and CD4+ T-cells are peculiar to both human and murine atherosclerotic lesions. There is a recent line of research favoring hypothetic allergic mechanisms in the genesis of atherosclerosis and, consequently, coronary artery disease (CAD), among which Interleukin (IL)-17 appears to be a key cytokine regulating local tissue inflammation. The objective was to add a piece of information on the role of IL-17 in the genesis of atherosclerosis. Eighty obese patients with normal liver enzyme levels but presenting with ultrasonographic evidence of NAFLD formed the population of this cross-sectional study. Anthropometric measures, data on excess adiposity, metabolic profile, serum concentrations of IL-17, eotaxin-3, IL-8, and CCL4/MIP1β, C-reactive protein, fibrinogen, ferritin, TNF-α, as well carotid intima-media thickness (IMT), a marker of atherosclerosis, and the main risk factors for CAD, such as blood pressure and smoking status, but also less determinant ones such as degree of NAFLD severity, Intramuscular Triglyceride storage and Resting Metabolic Rate were evaluated. Serum concentrations of Il-17 were detected as related to those of inflammatory cytokines, IL-6, IFN-γ and TNF-α. Furthermore, circulating levels of IL-17 were linked to those mirroring allergic process, IL-8, CCL4/MIP1β and eotaxin. Early atherosclerosis, evidenced as increased IMT, was not associated with circulating IL-17 levels. At multiple regression,IMT was predicted, other than by age, by the amount of the visceral adiposity, expressed as visceral adipose tissue at ultrasonography, and by serum eotaxin. In conclusion, a strong relationship was found between the IL-17-related chemokine eotaxin and IMT. The association found between the amount of visceral fat and circulating levels of eotaxin on the one hand, and IMT on the other, could reinforce the hypothesis that IL-17, released by the visceral adipose tissue, induces eotaxin secretion via the smooth muscle cells present in the atheromatosus vessels.

Carotid intima-media thickness is predicted by combined eotaxin levels and severity of hepatic steatosis at ultrasonography in obese patients with Nonalcoholic Fatty Liver Disease

BACKGROUND

Non-Alcoholic Fatty Liver Disease (NAFLD) is a distinct coronary artery disease (CAD) risk factor. The atherosclerotic process predisposing to CAD includes altered lipid profile and inflammatory processes. The available evidence suggests that increased circulating levels of eotaxin, an eosinophil chemoattractant cytokine implicated in allergic responses, are detected in the serum of patients with CAD. Relationships were sought between serum eotaxin on the one hand, and intima-media thickness--an early predictor of the atherosclerotic process, hepatic steatosis, arterial blood pressure values, as well as inflammation/immune markers and angiogenetic factors--on the other.

METHODS

Eighty obese patients with NAFLD, diagnosed at ultrasonography, without evident cytolysis, formed our study population. Anthropometric measures, metabolic profile, serum concentrations of interleukin-1β, C-reactive protein, interleukin-6, fibrinogen, ferritin, TNF-α, spleen size, vascular endothelial growth factor, platelet-derived growth factor-BB and heat shock protein-70 were evaluated.

RESULTS

Serum eotaxin concentrations were distinctly associated with TNF α, IL-6, IL-1β, VEGF and PDGF-BB levels but not with CRP, fibrinogen, heat shock protein-70 or spleen size. Among the metabolic and anthropometric parameters, a significant predictive power emerged when comparing eotaxin to insulin resistance, expressed as HOMA. NAFLD was distinctly associated with HOMA (P = 0.0005). Intima-media thickness was well predicted by both eotaxin levels and severity of NAFLD at ultrasonography, although no relation was detected between these last two variables.

DISCUSSION AND CONCLUSION

A role for insulin resistance in mediating the interplay between eotaxin and other inflammation/immune parameters could be evidenced in the induction/maintenance of atherosclerosis of obese patients with NAFLD.

Nesfatin-1: role as possible new anti-obesity treatment

In this article, we review on the current concepts about Nesfatin-1 as a new anti-obesity treatment and evaluate the existing issues in the context of this knowledge and the available literature. The intent is to enable clinicians to know Nesfatin-1 as a new anti-obesity treatment and make rational decisions based on this perspective as possible clinical application. Future research should seek to clarify whether Nesfatin-1 would be beneficial in the management of obesity.

Should visceral fat be reduced to increase longevity?

Several epidemiologic studies have implicated visceral fat as a major risk factor for insulin resistance, type 2 diabetes mellitus, cardiovascular disease, stroke, metabolic syndrome and death. Utilizing novel models of visceral obesity, numerous studies have demonstrated that the relationship between visceral fat and longevity is causal while the accrual of subcutaneous fat does not appear to play an important role in the etiology of disease risk. Specific recommended intake levels vary based on a number of factors, including current weight, activity levels, and weight loss goals. It is discussed the need of reducing the visceral fat as a potential treatment strategy to prevent or delay age-related diseases and to increase longevity.

Physical activity: an important adaptative mechanism for body-weight control

We review the current concepts about energy expenditure and evaluate the physical activity (PhA) in the context of this knowledge and the available literature. Regular PhA is correlated with low body weight and low body fat mass. The negative fat balance is probably secondary to this negative energy balance. Nonexercise activity thermogenesis (NEAT) and physical activity, that is crucial for weight control, may be important in the physiology of weight change. An intriguing doubt that remains unresolved is whether changes in nutrient intake or body composition secondarily affect the spontaneous physical activity.

Inhibition of milk secretion by intraperitoneal injections of milk into lactating mice

The effect of milk reabsorption upon lactation was studied by giving daily intraperitoneal injections of milk to lactating mice during the first 5 days of lactation.

The weight gain of the young of mice injected with mouse or cow milk was similar but was less than the gain of the young of the non-injected control mice. The weight gain of the young of the mothers receiving lipid-free cow milk was similar to that of the controls, whereas that of the young of mothers receiving lipid-free cow milk with added lipids was again less than in the control group. There was no difference in litter mortality rate between the controls and the group treated with lipid-free cow milk, nor between the groups treated with mouse, cow and lipid-free cow milk with added lipids; the mortality, however, in the three latter groups was higher than in the two former ones. The injection of milk decreased milk yield. The effect of the injection of milk was observed within 24 h of the first injection.

The results suggest that milk secretion is impaired by the injection of milk. The effect may be ascribed to the lipid fraction of milk or to some unknown chemical factor within it. The rapid onset of the effect suggests that it is not mediated by an immunological reaction.