S. Lombardini

Review article: hepatic steatosis and insulin resistance

Hepatic steatosis may be both an adaptive phenomenon and an example of lipotoxicity. Its prevalence ranks in the same order of magnitude of insulin resistance in the general population. Studies support the finding that hepatic steatosis is secondary to insulin resistance and not vice versa. A steatotic liver will further contribute to the development of insulin resistance through impaired clearance of insulin from the portal blood, creating a vicious cycle. Insulin resistance is the leading force in the pathogenesis and natural history of non‐alcoholic fatty liver disease. Dysfunction of energetic homeostasis and the interaction of adiponectin, leptin and tumour necrosis factor‐α are key events in the pathogenesis of steatosis and insulin resistance. Insulin resistance represents the frame within which hepatic and extrahepatic non‐alcoholic fatty liver disease‐related clinical manifestations are to be anticipated and interpreted.

Gallstone disease in non-alcoholic fatty liver: Prevalence and associated factors

Background:  Insulin resistance is a risk factors for non‐alcoholic fatty liver disease (NAFLD) and for gallstone disease (GD). Aims of the present study were to assess the prevalence of and factors associated with GD in unselected patients with NAFLD.

Review article: the metabolic syndrome and non‐alcoholic fatty liver disease

Metabolic syndrome represents a common risk factor for premature cardiovascular disease and cancer whose core cluster includes diabetes, hypertension, dyslipidaemia and obesity. The liver is a target organ in metabolic syndrome patients in which it manifests itself with non‐alcoholic fatty liver disease spanning steatosis through hepatocellular carcinoma via steatohepatitis and cirrhosis. Given that metabolic syndrome and non‐alcoholic fatty liver disease affect the same insulin‐resistant patients, not unexpectedly, there are amazing similarities between metabolic syndrome and non‐alcoholic fatty liver disease in terms of prevalence, pathogenesis, clinical features and outcome. The available drug weaponry for metabolic syndrome includes aspirin, metformin, peroxisome proliferator‐activated receptor agonists, statins, ACE (angiotensin I‐converting enzyme) inhibitors and sartans, which are potentially or clinically useful also to the non‐alcoholic fatty liver disease patient. Studies are needed to highlight the grey areas in this topic. Issues to be addressed include: diagnostic criteria for metabolic syndrome; nomenclature of non‐alcoholic fatty liver disease; enlargement of the clinical spectrum and characterization of the prognosis of insulin resistance‐related diseases; evaluation of the most specific clinical predictors of metabolic syndrome/non‐alcoholic fatty liver disease and assessment of their variability over the time; characterization of the importance of new risk factors for metabolic syndrome with regard to the development and progression of non‐alcoholic fatty liver disease.

Review article: diabetes, genetics and ethnicity

The prevalence of insulin resistance and diabetes has increased in the past decades at an alarming rate in all Western countries and in those countries which are adopting a ‘western life style’. This trend suggests the impact of environmental factors such as diet, obesity and physical activity on the pathogenesis of diabetes. However it is known that the prevalence and variation of prevalence, as consequence of environmental changes, it is different in various ethnic groups. Studies conducted in multiethnic populations suggest that some ethnic groups, such as Hispanics or Asian Indians, might have a particular predisposition, possibly on genetic basis, to develop insulin resistance and diabetes, when exposed to adverse conditions. According to the ‘thrifty gene’ hypothesis, a clustering of different genetic defects or polymorphisms, developed as genetic advantage in some populations, could predispose some ethnic groups to insulin resistance and diabetes in presence of an increased food supply. Multiple mutations, associated with small changes in insulin sensitivity, when combined, may induce a significant reduction in insulin sensitivity. This review deals with the possible relevance of genetic factors in the expression of insulin resistance and diabetes in relation to ethnicity.

Inflammatory bowel diseases and human reproduction: A comprehensive evidence-based review

To evaluate the effects of inflammatory bowel diseases (IBDs) on human reproduction, we reviewed the current literature using a systematic search for published studies (articles and/or abstracts) without limits for English language. We searched on Medline (through PubMed), the Institute for Scientific Information, the Web of Science and the websites for the registration of controlled trials (http://controlled-trials.com/). Bibliographies of retrieved articles, books, expert opinion review articles and reviewed bibliographies from subject experts were manually searched. Titles and abstracts were screened initially, and potential relevant articles were identified and reviewed. Whenever possible, data were analyzed by comparing IBD patients vs healthy controls, and patients with active IBDs vs those with disease in remission. The effects of IBDs on female fertility, fertility in infertile couples, pregnancy and male infertility were examined separately. Patients with IBDs in remission have normal fertility. At the moment, there is no established guideline for the preservation of fertility in women with IBD undergoing surgery. Further data are needed regarding guidelines for the management of these patients. Data regarding IBDs and infertility are currently completely lacking. Considering the prevalence of intestinal pathology in young adults of childbearing age, this field is of great scientific and clinical interest, opening up important future perspectives. Another important and as yet unexplored point is the response to treatments for infertility in patients with IBDs. In particular, the question is whether the reproductive outcomes (clinical and biological) can be influenced by the IBD of one of the partners. The goals for successful reproductive outcomes in IBD population are correct counseling and disease remission. IBDs significantly affect several reproductive aspects of human (female, male, couple) reproduction. Further data are needed to develop guidelines for the clinical management of subjects of reproductive age with IBDs.