Intrauterine growth retardation and nonalcoholic Fatty liver disease in children

Intrauterine growth retardation (IUGR), the most important cause of perinatal mortality and morbidity, is defined as a foetal growth less than normal for the population, often used as synonym of small for gestational age (SGA). Studies demonstrated the relationships between metabolic syndrome (MS) and birthweight. This study suggested that, in children, adolescents, and adults born SGA, insulin resistance could lead to other metabolic disorders: type 2 diabetes (DM2), dyslipidemia, and nonalcoholic fatty liver disease (NAFLD). NAFLD may evolve to nonalcoholic steatohepatitis (NASH), and it is related to the development of MS. Lifestyle intervention, physical activity, and weight reduction represent the mainstay of NAFLD therapy. In particular, a catch-up growth reduction could decrease the risk to develop MS and NAFLD. In this paper, we outline clinical and experimental evidences of the association between IUGR, metabolic syndrome, insulin resistance, and NAFLD and discuss on a possible management to avoid the risk of MS in adulthood.

Mirnome analysis reveals novel molecular determinants in the pathogenesis of diet-induced nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is an emerging disease with a broad spectrum of liver conditions. The complex molecular pathogenesis of NAFLD is still unclear. In this study, we conducted an analysis of microRNA (miRNA) expression profiles in liver of rats made NAFLD by different diets. To this aim, Sprague-Dawley rats were fed ad libitum for 3 months with different diets: standard diet (SD), diet enriched in fats and low in carbohydrates (HFD), SD with high fructose (SD-HF) and diet with high levels of fats and fructose (HFD-HF). Our results demonstrated that the treatment with different dietetic regimens caused a significant increase of the body weight and the alteration of some metabolic parameters compared with control animals, as well as various liver injuries. The miRNAs analysis showed the significant downregulation of three miRNAs (miR-122, miR-451 and miR-27) and the upregulation of miR-200a, miR-200b and miR-429 in HFD, SD-HF and HFD-HF rats. Besides, miR-21 expression was significantly decreased only in fructose-enriched diets. These miRNAs target molecules involved in the control of lipid and carbohydrate metabolism, signal transduction, cytokine and chemokine-mediated signaling pathway and apoptosis. Western blot analysis of PKCδ, LITAF, ALDOLASE-A, p38MAPK, PTEN, LIPIN1, EPHRIN-A1, EPHA2 and FLT1 showed a diet-induced deregulation of all these proteins. Interestingly, the expression pattern of LITAF, PTEN, LIPIN1, EPHRIN-A1, EPHA2 and FLT1 might be well explained by the trend of their specific mRNAs, by potentially regulatory miRNAs, or both. In conclusion, we highlight for the first time the potential involvement of novel determinants (miRNAs and proteins) in the molecular pathogenesis of diet-induced NAFLD.

Glutathionylation of p65NF-kappaB correlates with proliferating/apoptotic hepatoma cells exposed to pro- and anti-oxidants

Oxidative stress influences a variety of regulatory proteins, including nuclear factor-kappaB (NF-kappaB). NF-kappaB is critical for maintaining the proliferation/apoptosis balance in hepatocytes. In this study we investigated the causal links between glutathione, NF-kappaB and hepatocyte damage. HepG2 and 3B cells were exposed to different doses of H2O2 or N-acetylcysteine (NAC) and the proliferation/apoptosis rate, glutathione forms, and p65NF-kappaB glutathionylation and activity were analysed. Our results demonstrate that H2O2 stopped proliferative response at low doses, but induced apoptosis only at high doses. In contrast, NAC exerted, proportionally to its concentration, a dual role simultaneously increasing both proliferation and apoptosis. Interestingly, the levels of protein-bound glutathione were increased by H2O2 and decreased by NAC. Moreover, the antibody recognizing the glutathionylated proteins co-precipitated and -localized with the cytoplasmic inactive form of p65NF-kappaB in H2O2- and NAC-treated cells, even when, in 1 mM NAC-treated cells, a part of p65 was glutathione-free and localized into the nucleus. Apoptotic cells were characterised principally by a cytoskeletal staining of glutathionylation and retention of NF-kappaB in the cytoplasmic region; whereas in proliferating cells, glutathionylated proteins were concentrated into the perinuclear region and p65NF-kappaB was traslocated into the nucleus. While cytoplasmic NF-kappaB retention correlated well with an increased apoptotic rate, a greater expression of this protein was observed in association with the NAC-dependent. In conclusion, our findings suggest that glutathionylation inhibits NF-kappaB activity causing reduced hepatocyte survival, which is common in several liver diseases.

Association between type two diabetes and non-alcoholic fatty liver disease in youth

In the last three decades prevalence of insulin related diseases has been growing worldwide with epidemic obesity, type 2 diabetes mellitus and non alcoholic fatty liver disease. In children such epidemics are particularly worrisome, since metabolic abnormalities track to the adulthood with significant implications for the health care system. Epidemiological studies support a close association between type 2 diabetes and fatty liver disease. We review the most recent epidemiological data on prevalence of both diseases in youth and their association.

Low birth weight and catch-up-growth associated with metabolic syndrome: a ten year systematic review

OBJECTIVE

We conducted a systematic review in order to: i. summarize the relationship between low birth weight, catch-up-growth and the metabolic syndrome, from publications during the past 10 years; and ii. study the potential role of an alternative nutritional approach to side effects of catch-up-growth.

METHODS

We reviewed all papers published in the past ten years assessing the possible association between low birth weight, catch-up-growth and the occurrence of some components of the metabolic syndrome, including insulin resistance, type 2 diabetes, dyslipidemia and non-alcoholic fatty liver disease.

RESULTS

We found 57 studies which described the relationship between metabolic syndrome associated features and low birth weight and catch-up-growth. The majority of the studies in children, adolescents and adults born small for gestational age (SGA) suggested that insulin resistance could represent the prelude to other metabolic disorders.

CONCLUSIONS

Both low birth weight and catch-up-growth seem to correlate with some aspects of a later metabolic syndrome.