Ewa Tomaszewska

Morphological changes of the cartilage and bone in newborn piglets evoked by experimentally induced glucocorticoid excess during pregnancy

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.

Hematological and serum biochemical parameters of blood in adolescent rats and histomorphological changes in the jejunal epithelium and liver after chronic exposure to cadmium and lead in the case of supplementation with green tea vs black, red or white tea

Rats were used to check whether regular consumption of black, red, or white tea would have a protective effect similar to the action of green tea on the intestine and liver in the case of exposure to Cd and Pb within the limits of human environmental exposure to these elements. Rats at the age of 6 weeks were divided into the control and four groups supplemented with green (GT), black (BT), red (RT), or white (WT) tea extracts. Their diet (except the control) was mixed with 7 mg Cd/kg and 50mg Pb/kg. The experiment lasted 12 weeks. The effects of administration of tea in Cd- and Pb-poisoned rats on plasma biochemical parameters and the jejunal epithelium and liver were determined. The highest body mass was found in the GT group. The highest hemoglobin and Fe concentrations were in the control and GT groups. The highest activity of AST was in groups poisoned with Cd and Pb independently on supplementation. The highest ALT activity was in BT and RT groups with lower content of polifenoles. Pb and Cd disturbed the liver leading to necrosis and fatty degenerative changes, and a loss of normal architecture of the hepatocytes. Rats from the GT group had the highest cell proliferation rate in intestinal glands and the largest absorptive surface. Black, red, and white tea exerted a varied impact on the histological structure and innervation of the small intestine wall as well as on the absorptive function of small intestine mucosa in rats poisoned with Pb and Cd than green tea. On the other hand, taking into account the number of apoptotic cells, the effect of the teas was the same. Moreover, it is clear that long term exposure to Cd and Pb contamination causes toxic effect in the liver.

Potato fiber protects the small intestinal wall against the toxic influence of acrylamide

OBJECTIVE Acrylamide is a neurotoxic, genotoxic substance present in many commonly consumed food products and has been shown to have carcinogenic effects in rodents. The protective effects (if any) of potato fiber preparations, composed of cell wall material from potatoes, against the toxic influence of dietary acrylamide on the small intestinal wall were investigated. METHODS Male mice of the BALB/c strain were used in the study. Acrylamide was administered to the mice in their drinking water (0.5 mg/kg of body weight per day) and one of two types of potato fiber preparations (heated or raw potato fiber preparation) was added to their feed (2% addition to their feed). Histomorphometry of the small intestinal wall, hemoglobin adducts of acrylamide, animal weight, and feed and water consumption analyses were performed. RESULTS Acrylamide altered the morphology and histology of the small intestinal wall, decreasing proliferation, myenteron and submucosal thicknesses, villus length, fractal dimension, crypt depth, crypt number, and the small intestinal absorptive surface. Conversely, apoptosis, hemoglobin adduct levels, intensity of epithelium staining, enterocyte number, villus epithelial thickness, and crypt width and parameters associated with nerve ganglia were increased. The two potato fiber preparations that were used abolished the negative influences of acrylamide on the small intestinal wall and had no influence on the hemoglobin adduct levels of acrylamide. CONCLUSION The negative impact of acrylamide on the histologic structure, regeneration, and innervation of the small intestinal wall and the absorptive function of the small intestinal mucosa can be abolished by dietary potato fiber preparations.

Postnatal administration of 2-oxoglutaric acid improves the intestinal barrier affected by the prenatal action of dexamethasone in pigs

OBJECTIVE The potential effects of the prenatal administration of dexamethasone and the postnatal treatment with 2-oxoglutaric acid on postnatal development of the small intestine of farm animals have not been examined experimentally. The aim of this study was to establish the changes in morphologic parameters of the small intestine damaged by the prenatal action of dexamethasone in piglets supplemented with 2-oxoglutaric acid. METHODS Three milligrams dexamethasone was administered intramuscularly every second day from day 70 of pregnancy to parturition and then piglets were supplemented with 2-oxoglutaric acid for 35 d of postnatal life (0.4 g/kg of body weight). The histomorphometry of the pig duodenum and jejunum was determined. Immunohistochemical staining with anti-Ki-67, CD3, null T cells, cadherin, claudin, and neurofilament antibodies was performed. RESULTS Maternal treatment with dexamethasone decreased and limited the expression of claudin and cadherin in the epithelium. Dexamethasone led to thinning of the myenteron of the duodenum and the middle part of the jejunum in weaned piglets and influenced duodenal glands that became more elongated compared with control glands. Moreover, 2-oxoglutaric acid increased cell proliferation and the amount and maturity of peripheral blood lymphocytes in the duodenum and jejunum. It supported epithelial integrity and changed the circularity of the nerve plexuses. CONCLUSION The 2-oxoglutaric acid administered to piglets while suckling induced a complete recovery from intestinal damage caused by the prenatal action of dexamethasone.

The lack of protective effects of tea supplementation on liver and jejunal epithelium in adult rats exposed to cadmium and lead.

Adult rats at the age of 12 weeks were divided into the control group and groups supplemented with green (GT), black (BT), red (RT), or white (WT) tea extracts. The diet (except that for the control) was mixed with 7 mg Cd/kg and 50 mg Pb/kg. The experiment lasted 12 weeks. Basal haematology and plasma biochemical parameters as well as the histomorphometrical parameters of jejunal epithelium and liver were determined. The lowest body mass was found in the RT and WT groups. Some functional (increased plasma ALT and AST, and the de Ritis coefficient) and structural changes in the liver (slight fatty degenerative changes, an increase in the intercellular space) were evident irrespective of the type of tea in the Cd and Pb poisoned rats. This toxic effect was visible especially in rats drinking black or red tea. However, the rats had no elevated LDH and ALT activities. The highest content of Cd and Pb in the liver and blood plasma was found in rats drinking red tea. Based on the results obtained, it is clear that long-term exposure of adult rats with a mature intestinal barrier to Cd and Pb contamination, under higher exposure conditions than the current estimates of weekly exposure of the general population to Cd and Pb through diet, causes a toxic effect, especially in the liver, and can change the structure of intestinal mucosa, irrespective of tea administration.

Effect of caponization on performance and quality characteristics of long bones in Polbar chickens.

&NA; The effect of caponization on the mechanical properties of Polbar chicken bones was the subject of investigation. The biomechanical strength of bones and the risk of their deformation or fracture were determined on the basis of their geometric, structural, material, and densitometric properties. Eight‐week‐old cockerels of Polbar breed were surgically castrated and then fattened until the 24th week of life. It was observed that caponization did not influence the weight and length of either of the long bones. It did however significantly reduce their ash content and the Ca and P contents in their femur, and P content in their tibia. Dual energy x‐ray absorptiometry densitometry revealed that bone mineral content of the mid‐diaphyseal part of both bones were reduced. Similarly, the bone tissue density of bones decreased. Caponization influenced the bones geometric structure increasing the internal and external diameters of the bones. The bone cross‐sectional area was greater in capons, and, consequently, the cross‐sectional moment of inertia and the radius of gyration significantly increased. However, the relative wall thickness and cortical index were not altered. The three‐point bending tests revealed the negative effect of caponization on the mechanical endurance of bones. Yield strength, Young modulus, and yield stress, characterizing the strength of the bones material, decreased in capons. That suggests a higher risk of permanent deformation as capon bones become less elastic. Concluding, caponization negatively influenced the quality characteristics of Polbar chicken long bones.

Alteration in bone geometric and mechanical properties, histomorphometrical parameters of trabecular bone, articular cartilage, and growth plate in adolescent rats after chronic co-exposure to cadmium and lead in the case of supplementation with green, black, red and white tea.

Adolescent male Wistar rats were used to check whether regular consumption of black, red, white, or green tea would have a protective effect on femur development during 12-week exposure to Cd and Pb (7mg Cd and 50mg Pb in 1kg of the diet). The animals were randomly divided (n=12) into a positive control (without Cd, Pb and teas), a negative control group (Cd and Pb), and groups supplemented additionally with green (GT), black (BT), red (RT), and white tea (WT). Heavy metals reduced the geometric and densitometric parameters and the total thickness of articular cartilage irrespective of tea administration and influenced mechanical endurance, growth plate thickness, and trabecular histomorphometry depending on the tea type. It is difficult to indicate which tea has the best protective effects on bone and hyaline cartilage against heavy metal action.

Effect of HMB and 2-Ox administered during pregnancy on bone properties in primiparous and multiparous minks (Neivison vison)

Abstract The aim of the study was to determine the mechanical and geometric properties as well as bone tissue density of long bones in primiparous and multiparous dams of minks supplemented with β-hydroxy β-methylbutyrate (HMB) and/or 2-oxoketoglutarate (2-Ox) during gestation. Powdered 2-Ox was given at the daily dosage of 0.4 g/kg b.w. separately or simultaneously with HMB, which was administered at the daily dosage of 0.02 g/kg b.w. The study demonstrates for the first time that administration of 2-Ox and/or HMB to dams markedly influences bone tissue density and the mechanical and geometrical properties of mother`s bones in minks. Moreover, it was demonstrated that the supplementation was more effective in the thoracic limb, which was comprehensively used in contrast to the pelvic limb. The mechanical parameters and bone tissue density significantly increased in the humerus in multiparous minks. Only such diet may provide satisfactory production results in the animals. Nutritional deficiencies occurring during pregnancies may trigger body`s own reserves to cover the bone mass increase in developing foetuses and support milk production. This can prevent regeneration of dams’ organisms, which negatively affects their reproductive performance. 2-Ox or HMB may be regarded as a protective metabolite when administered orally to minks, counteracting the negative influences of pregnancy and lactation periods on bones condition. Both simultaneous treatment with 2-Ox and HMB and their separate administration were equally effective.

Can 2-oxoglutarate prevent changes in bone evoked by omeprazole?

OBJECTIVE Proton-pump inhibitors, such as omeprazole, are widely used in the prevention and treatment of gastroesophageal diseases. However, an association between proton-pump inhibitors and the increased risk of bone fractures has been observed, especially in patients treated for extended periods. Conversely, 2-oxoglutarate, a precursor of hydroxyproline, the most abundant amino acid in bone collagen, counteracts the bone loss. The aim of the present study was to elucidate the influence of omeprazole on bone and investigate whether dietary 2-oxoglutarate supplementation could prevent the effects of omeprazole. METHODS Eighteen male Sprague-Dawley rats were used. Rats received omeprazole in the diet and 2-oxoglutarate in the drinking water. Body and organ weights and serum concentrations of cholecystokinin and gastrin were measured. The femurs, tibias, and calvarias were collected. Histomorphometric analysis of bone and cartilage tissues was conducted. Bone densitometric and peripheral quantitative computed tomographic analyses of the femur and tibia were performed. RESULTS Omeprazole decreased the femur and tibia weights, the mechanical properties of the femur, the volumetric bone density and content, the trabecular and cortical bone mineral content, the total, trabecular, and cortical bone areas, the mean cortical thickness, and the periosteal circumference of the femur. Omeprazole had a minor effect on the examined bone morphology and exerted negligible effects on the cartilage. 2-Oxoglutarate lowered the gastrin concentration. CONCLUSIONS Omeprazole treatment exerts its effects mostly on bone mineralization and cancellous bone, adversely affecting bone properties. This adverse effect of omeprazole was not markedly abolished by 2-oxoglutaric acid, which acted as an anti-hypergastrinemic agent.

Comparison of the effect of dietary copper nanoparticles with copper (II) salt on bone geometric and structural parameters as well as material characteristics in a rat model

Copper is required for normal functioning of all basic biochemical and physiological processes in the body. The objective of this study was to compare the effect of two different chemical forms (carbonate and nanoparticles) of Cu administered in feed mixtures to growing rats on bone geometric and structural parameters as well as material characteristics in a rat model. For this purpose, five experimental treatments were used to evaluate the effects of different levels of Cu applied in the diet as a mineral mixture (the standard dose of 6.5mg/kg diet, half the standard dose, and no Cu in mineral mixture as a negative control) and two Cu sources (CuCO3 - commonly used in rodent laboratory diets and a Cu-NP nanoparticle preparation, 40nm). There were no changes in body weight and bone morphology, but significant alteration was noted in the geometry and mechanical parameters, which was Cu-NP-dose dependent. Our study showed an increase in the ultimate load and toughness in Cu-NP-treated rats at the standard concentration. The higher values of the studied parameters prove that there was a change in bone mineralization. Although bone mineral density and content were not changed, bone tissue density and ash increased. The XRD analysis revealed that some peaks did not originate from hydroxyapatite, and they indicated existence of other mineral phases. No studies conducted so far have provided a detailed mechanical X-ray diffraction analysis of bone tissue of growing rats administered with diet containing Cu nanoparticles. This study showed that Cu-NP given in low dose increased mechanical endurance of bone, without the changes in strain and stress compared to low dose of Cu given in traditional form.