Effect of Strontium Ranelate on Femur Densitometry and Antioxidative/Oxidative Status in Castrated Male Rats

The studies were aimed at determinatning of the effect of strontium ranelate (SR) on the mineralization  processes and selected parameters of oxidative stress in orchidectomized rats during the development of  osteopenia. Male Wistar rats were sham-operated (SHO) and orchidectomized (ORX). ORX animals were  divided into control (ORX-C) and gavaged with SR (ORX-SR), at a dose of 900mg/kg/b.w. After 60 days  the animals were scanned for determination of bone mineral density (BMD) of the whole skeleton. Isolated  femora were examined by DEXA and pQCT. Tomographic measurements were performed for a total  slice and separately for the cortical and trabecular parts of the distal end of the femora. The intensity of  lipid peroxidation (ILP) and total antioxidant capacity (TAC) in blood serum were measured. SR treatment  increased vBMD and BMC of total, trabecular and cortical bone in ORX rats compared to ORX-C and  SHO rats. ORX significantly increased TAC in control animals, and SR limited this increase. ILP in SHO  and ORX-C rats which on a similar level. SR increased ILP by 21.3%, as compared to SHO. SR improved  densitometric and geometric parameters of femora by orchidectomized rats what prevented degradation of  bone tissue. Beneficial effects of SR were also demonstrated in stabilization of TAC in ORX rats at the level  noted in SHO rats.

Antioxidant defence of colostrum and milk in consecutive lactations in sows

<p>Abstract</p> <p>Background</p> <p>Parturition is supposed to be related to oxidative stress, not only for the mother, but also for the newborn. Moreover, it is not clear whether consecutive pregnancies, parturitions, and lactations are similar to each other in regards to intensity of metabolic processes or differ from each other. The aim of the study was to compare dynamic changes of antioxidative parameters in colostrum and milk of sows taken during 72 h postpartum from animals in consecutive lactations. Activities of glutathione peroxidase (GSH-Px), glutathione transferase (GSH-Tr), and superoxide dismutase (SOD), and amount of vitamin A and C were measured. Healthy pregnant animals were divided into 4 groups according to the assessed lactation: A -1^stlactation (n = 10), B - 2^ndand 3^rdlactation (n = 7), C - 4^thand 5^thlactation (n = 11), D - 6^th- 8^thlactation (n = 8). The colostrum was sampled immediately after parturition and after 6, 12, 18 and 36 h while the milk was assessed at 72 h after parturition. Spectrophotometric methods were used for measurements.</p> <p>Results</p> <p>The activity of antioxidative enzymes and the concentration of vitamin A increased with time postpartum. The concentration of vitamin C was the highest between the 18th and 36th h postpartum.</p> <p>Conclusions</p> <p>Dynamic changes in the values of antioxidant parameters measured during the study showed that sows milk provides the highest concentration of antioxidants in the 2^ndand 3^rdand 4^thand 5^thlactation giving the best defence against reactive oxygen species to newborns and mammary glands.</p

Concentration of serum amyloid A and ceruloplasmin activity in milk from cows with subclinical mastitis caused by different pathogens

The aim of the present study was to determine the concentration of serum amyloid A (SAA) and the activity of ceruloplasmin (Cp) in milk from cows with subclinical mastitis caused by different pathogens. Eighty-four milk samples from cows with subclinical mastitis and fourteen milk samples from healthy cows were examined. SAA concentration was determined using the commercial ELISA kit (Tridelta Development Ltd., Greystones, Wicklow, Ireland). Cp activity was assessed spectrophotometrically, using the Rice method. The results reveal that the concentration of SAA (with exception of CNS) and activity of Cp in cow milk can be regarded as markers of subclinical mastitis, irrespective of the microorganism inducing the disease. In conclusion, measurement of SAA and Cp in milk samples could be a useful method in diagnosing subclinical mastitis in cows, but the method should be adapted for field use

Assessment of lipid and protein peroxidation markers in non-pregnant and pregnant female dogs

The aim of the study was to investigate oxidative stress during normal pregnancy in female dogs based on an evaluation of plasma markers for lipid and protein peroxidation. Twenty clinically healthy female dogs (10 non-pregnant and 10 pregnant) were used in the study. Blood samples from the pregnant animals were collected at 19-21, 38-40, and 56-58 days of pregnancy. Blood samples from non-pregnant female dogs were obtained between 20 and 35 days after ineffective breeding. As indicators of oxidative stress, we measured the following using spectrophotometric and spectrof-luorimetric methods: thiobarbituric acid reactive substances (TBARS), radical cations of N,N, die-thylpara-phenylene diamine (RC-DEPPD), sulfhydryl groups (SH groups), bityrosine and formyl-kynurenine. The mean plasma TBARS concentration in the pregnant dogs (0.486 ± 0.071 - 0.581 ± 0.191 |imol/g protein) was significantly higher (p<0.05) than that found in the non-pregnant animals (0.274 ± 0.111 |imol/g protein). A marked, although not significant, decrease in SH group content, as well as an increase in bityrosine and formylkynurenine concentration were concurrently observed in the pregnant dogs. No significant differences were found in terms of the studied markers in the pregnant animals when comparing the values obtained during the investigated periods of pregnancy, although there was a progressive decrease in TBARS concentration and a progressive increase in RC-DEPPD, bityrosine and formylkynurenine contents. Our findings suggest that normal pregnancy in female dogs is associated with oxidative stress. Further studies are necessary to establish the physiological ranges of antioxidative/oxidative profiles in pregnant dogs and to explain if and how the intensity of oxidative stress might contribute to the risk of the complications of pregnancy