Excess fat deposition and insulin resistance are considered the main risk factors for nonalcoholic fatty liver disease (NAFLD), and therefore, not surprisingly, the global prevalence of NAFLD increases in parallel with both obesity and type 2 diabetes. Although deterioration of bone homeostasis in patients with NAFLD is commonly observed, its etiology has not been fully elucidated yet. It was shown in several studies that bone tissue seems to be independently associated with NAFLD. A mechanistic perspective puts the liver at the center of mutual interdependencies obviously involving adipose tissue and muscles and also the bone matrix and bone cells, which are relatively novel. In this review, various pathophysiological mechanisms and possible mediating molecules that may interplay between NAFLD and bone tissue are described. Chronic inflammation, vitamin D3, growth hormone, insulin-like growth factor 1, osteopontin, fetuin-A, irisin, osteocalcin, and osteoprotegerin from osteoblasts have been proposed as mediators of mutual interactions among the skeleton, fatty tissue, and liver. Although to date there are still many issues that have not been elucidated, growing evidence suggests that screening and surveillance of bone mineral density in patients with NAFLD should be considered in future strategies and guidelines for NAFLD management.

The structural quality of the connective tissue is genetically determined and is influenced by hormonal and nutritional modification. An effect of a 2-Ox-rich diet on bone mineralization and structure and expression of non-collagenous protein in articular and growth cartilages of maternal dexamethasone-treated 9-month-old boars was considered in this study. Sows were treated i.m. with dexamethasone at the dose of 0.03 mg kg⁻¹ body weight every second day during the last 45 days of pregnancy. After the birth, the boars were divided into two groups: administered and not supplemented with 2-Ox for 9 months (0.4 g/kg body weight/day). Dexamethasone given during the prenatal time inhibited the growth and negatively influenced the mechanics, geometry and histomorphometrical parameters of long bones and cartilage irrespective of the diet. Moreover, maternal dexamethasone treatment resulted in expression of osteocalcin in the articular cartilage, and the diet rich in 2-Ox limited the OC expression. This study demonstrated that changes observed in adult boars initiated by dexamethasone treatment in the prenatal period were persistent and long-term use of alimentary 2-Ox supplementation can counteract only some of the destructive changes evoked by prenatal dexamethasone excess.

Objective. The aim of the study was to determine the effect of α‐ketoglutarate on the blood lipid profile using a rat animal model with experimentally induced hypercholesterolaemia. Material and methods. The female and male (30/30) Wistar rats had ad libitum access to a diet containing cholesterol (1 %) and lard (10 %) throughout the entire experimental period (120 days). On day 60 of the study, both the females and the males were divided into three groups, the first receiving a mixture of drinking water adjusted to pH 4.6 using HCl (control), the other two (experimental groups) receiving a solution containing 0.01 M and 0.1 M α‐ketoglutarate (AKG) (pH adjusted to 4.6). Blood samples were taken on days 0, 30, 60 and 120. Results. The concentrations of total cholesterol, triglycerides, HDL and LDL, respectively, in the blood serum were estimated spectrophotometrically. During the entire experimental period the total cholesterol, triglycerides and LDL levels of the control rats increased, whereas that of HDL decreased. The serum concentrations of total cholesterol, LDL and triglycerides in both the experimental groups receiving AKG decreased (days 60 to 120) (p<0.05), while the HDL concentration tended to increase. The body gain in all groups receiving AKG was significantly lower than in the control group. Conclusions. These observations clearly prove that oral treatment with AKG can decrease the risk of hypercholesterolaemia developing and can lower the body weight. The relative concentrations of the plasma LDL and HDL changed to a more favourable ratio promoting good health.