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The study examined articular and growth plate cartilages as well as bone tissues in the offspring of sows treated with glucocorticoid during the last 45 days of pregnancy (dexamethasone at the dose of 0.03 mg/kg body weight intramuscularly, every second day). The offspring were tested at the birth and basal morphology for both articular and growth plate cartilages, and the histomorphometry of trabeculae of the epiphysis and metaphysis of femur and tibia were established. The concentration of selected cytokines and the activity of bone alkaline phosphatase were determined in blood serum. Maternal dexamethasone (DEX) administration reduced the thickness of proliferative, resting and hypertrophic zones of growth plate of femur and tibia of male piglets when compared with the control. DEX significantly reduced the thickness of the resting zone in both bones. It also elongated proliferative and hypertrophic zones of the growth plate in the femur as well as the hypertrophic zone in the tibia of female piglets when compared with the control group. Moreover, DEX decreased the articular cartilage thickness of the tibia in female piglets and enhanced the articular cartilage thickness of the femur in male piglets. Articular cartilage was highly cellular, and chondrocytes were separated by thin septa of matrix. An analysis of the trabecular bone architecture in male piglets showed a loss of the trabecular bone by thinning and DEX-related increase in trabecular porosity. Moreover, the cortical bone looked similar to the trabeculae because of trabecularization of the cortex. There was a DEX that reduced serum osteocalcin and BAP concentrations in both female and male newborn piglets, whereas the serum IL-1 and Il-6 was reduced only in male piglets. The obtained results demonstrated that DEX administration to sows during the last 45 days of pregnancy might cause the growth to slow and eventually to stop, especially in male piglets. It might lead to an alteration within the cartilage during its normal function, and with the time, arthritic changes can follow.

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AbstractAcrylamide (AA) is a chemical substance with a potentially carcinogenic effect. Its presence in food or animal food arises from its thermal processing. The experiment was conducted to evaluate the effect of AA exposure (3.0 mg/ kg. b.w. /day) of pregnant dams during the second half of the pregnancy on bone development in offspring. As an model animal, guinea pig was used. While term body weight of newborns was not influenced by maternal AA treatment, shorter bones with reduced bone diaphysis cross-sectional area were observed in experimental group. Numerous negative, offspring sex-dependent effects of maternal AA exposure were observed in femoral epiphysis and metaphysis as well as the articular and growth plate cartilages. This effects resulted from the AA-inducted alterations in bone metabolism, as indicated by the changes in the expression of numerous proteins involved in bone development: receptor activator of nuclear factor kappa-Β ligand (RANKL), tissue inhibitor of metalloproteinases 2 (TIMP-2), bone morphogenetic protein 2 (BMP-2), vascular endothelial growth factor (VEGF), and cartilage oligomeric matrix protein (COMP), all of which expression was measured as well as distribution of immature collagen fibres was determined. Based on the results, it can be concluded that the exposure of pregnant dams to AA negatively affected the structure compact bone in bone diaphysis, microarchitecture of trabecular bone in metaphysis and epiphysis as well as the structure of the articular and growth plate cartilages in their offspring. The AA-induced bone impairment increased osteoclast differentiation, as observed through the change in the RANKL/OPG ratio, which in turn inhibited osteoblast function by decreasing the expression of other proteins. The data of the present study suggests that maternal AA exposure can result in insufficient bone gain and even bone loss after the birth.

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The stomach is responsible for the processing of nutrients as well as for the secretion of various hormones which are involved in many activities throughout the gastrointestinal tract. Experimental adult male Wistar rats (n = 6) underwent a modified gastrectomy, while control rats (n = 6) were sham-operated. After six weeks, changes in small intestine (including histomorphometrical parameters of the enteric nervous plexuses) and liver morphology, immunolocalization of leptin, ghrelin and nesfatin-1 as well as proteins forming adherens and tight junctions (E-cadherin, zonula occludens-1, occludin, marvelD3) in intestinal mucosa were evaluated. A number of effects on small intestine morphology, enteric nervous system ganglia, hormones and proteins expression were found, showing intestinal enteroplasticity and neuroplasticity associated with changes in gastrointestinal tract condition. The functional changes in intestinal mucosa and the enteric nervous system could be responsible for the altered intestinal barrier and hormonal responses following gastrectomy. The results suggest that more complicated regulatory mechanisms than that of compensatory mucosal hypertrophy alone are involved.

Objective. The aim of the study was to determine the effect of nesfatin-1 on bone properties in female rats in the conditions of developing osteopenia induced by ovariectomy (OVX). Materials and method. The experiment was performed on 21 female Wistar rats assigned to 3 groups receiving intraperitoneally physiological saline (SHO, OVX-PhS) and nesfatin-1 in dose 2 μg/kg BW of (OVX-NES) once a day for 8 wks. At the end of the experiment, the rats were scanned using the DXA method to determine the body composition, tBMC, and tBMD. The isolated femora and tibia were tested with the DXA method for BMD and BMC, and with the pQCT method for separate analysis of the cortical and trabecular bone tissue. The bone strength parameters were also determined. The immunohistochemical method was used for determination of nesfatin-1 localization in growth cartilage. Bone metabolism markers (osteocalcin, bALP, and NTx) were identified using an ELISA kit. Results. OVX exerts a negative effect on bone tissue. The nesfatin-1 administration influenced positively the DXA parameters of tibia. TvBMD and TbvBMD measured by pQCT in metaphysis of bones were significantly higher in the OVX-NES group than in OVX-PhS. No differences were found in the values of bone strength parameters between SHO and OVX-NES females. Extra-and intracellular immunohistochemical reaction for nesfatin-1 was observed in all zones of growth cartilage, with the strongest reaction detected in the calcifying zone. Nesfatin-1 administration caused a significant increase in the osteocalcin and bALP concentration in relation to the OVX-PhS animals. Conclusion. The results of the experiment indicate that nesfatin-1 exerts a protective effect on bone tissue properties and can be used in the prevention of osteoporosis.