In seaarch of new potential markers for male fertility and semen quality control. Aquaporins in reproductive system and metabolomic profiling of semen.

Male infertility is one of the many problems currently faced by science and medicine. Despite intensive research in this area conducted in recent years, the reasons for the lack of the desired pregnancy are often unrecognized. The current standards and general recommendations, including the World Health Organization (WHO) guidelines for diagnostic testing of male reproductive organs and sperm quality analysis, seem to be insufficient. Hence, it has been postulated for years that it is necessary to search for and identify new, unknown factors that significantly affect male fertility, and to define modern indicators/biomarkers that would enable precise determination of male reproductive potential. Among the many interesting recently published data, the information on the identification and expression analysis of aquaporins (AQPs) in the male reproductive system and metabolomic semen analysis is of particular interest. In this review, we will try to solve the question whether AQPs and metabolomic sperm analysis can be the answer to the current needs and whether their measurements may become a useful parameter in the future for determining male reproductive potential.

Diet supplemented either with dried chicory root or chicory inulin significantly influence kidney and liver mineral content and antioxidative capacity in growing pigs.

According to the Regulation No. 1831/2003 of the European Parliament and European Union Council, the use of antibiotics as a dietary supplements has been prohibited. It seems that the administration of prebiotics, instead of antibiotics, into the pig's diet, may regulate the intestinal microbiota and has a long-term health-related impact on the host. Inulin-type fructans can stimulate mineral absorption from the gut. Additionally, it may regulate energy metabolism and activate enzymatic mechanisms preventing oxidative stress. The goal of the present study was to estimate the influence of dietary supplementation with dried chicory root or native chicory inulin on 1) liver histology; 2) liver and kidney lipid metabolism indices, activity of selected enzymes, concentration of macro- and micronutrients and heavy metals; 3) blood plasma, liver and kidney oxidative stress biomarkers and 4) blood plasma water-electrolyte homeostasis indices in growing pigs. The nutritional study was conducted on 24 piglets assigned to 3 dietary groups (n = 8): control (C) fed a basal diet and two experimental groups receiving basal diet supplemented with 2% of inulin (IN) either 4% of dried chicory root (CR). The animals were fed with a group-specific diets for 40 days and then subjected to euthanasia. Subsequently, blood, liver and kidney samples were harvested for further processing. In the control and experimental groups, no apparent morphological abnormalities in the liver tissues were seen. The percent of periodic acid Schiff positive glycogen liver cells was significantly lower in the CR group as compared to C and IN groups (P < 0.001). Chicory root supplementation improved blood plasma prooxidative-antioxidative balance - PAB (P < 0.001) and liver PAB (P < 0.01) and thiobarbituric acid reactive substances - thiobarbituric acid-reactive substances (P < 0.05). Feeding the CR diet increased calcium (P < 0.001) and potassium (P < 0.05) and decreased cadmium (P ≥ 0.05) content in the liver when compared to the C group. Administration of the CR and IN diets increased selenium (Se) and sodium concentrations, whereas decreased zinc content both in the liver (P < 0.01; P < 0.05 and P < 0.05, respectively) and in the kidney (P < 0.01; P < 0.001 and P < 0.001, respectively) of pigs. Additionally, a higher concentration of lead (P < 0.05) was observed in the kidney of pigs fed the CR diet. In conclusion, both dietary supplements had a potential to significantly improve the Se status and oxidoreductive homeostasis in growing pigs.

Mytilus hybridisation and impact on aquaculture: A minireview.

The three species in the blue mussel complex (Mytilus edulis, Mytilus galloprovincialis and Mytilus trossulus) show varying levels of hybridisation wherever they occur sympatrically. The spatial variation in hybridisation patterns is potentially governed by environmental conditions, larval dispersal and aquaculture practices. Commercial mussel cultivation has been shown to increase hybridisation through introduction of non-native species or spat transfer. There is evidence that mussel cultivation may promote commercially less desirable phenotypes (e.g. fragile shells), however, to what extent hybridisation impacts aquaculture is currently not clear. The aim of this review is to summarize the available information on Mytilus hybridisation patterns in Europe and their promotion through aquaculture practices in order to shed light on the overall implications for the aquaculture industry.

Aquaglyceroporins in the kidney: present state of knowledge and prospects.

Aquaporins belong to a family of small, transmembrane proteins that form channels selectively permeable for water. Some of them known as aquaglyceroporins also enable transportation of other small molecules such as glycerol, urea or ammonia. To date, 13 isoforms of aquaporins has been discovered in mammals (AQP0 - AQP12), 9 of which is localized in different parts of the renal tubular epithelium. In recent years, particular interest has been paid to aquaporins selectively permeable only to water molecules, determination of their localization and expression allowed to define the role of these proteins in renal excretion of water and their importance in the development of diseases. Alas, thus far the role in the physiological processes of the aquaglyceroporins localized in the kidneys has not been fully determined. This review summarizes our current knowledge on additional transport functions of renal AQPs (AQP3, AQP6, AQP7 and AQP8). On the basis of the information gathered and the opinions by many authors, it has been found that aquaglyceroporins are most probably the key element in the renal regulation of nitrogen balance and maintenance of the correct pH of body fluids. Elucidating additional transport functions of AQPs in the kidney will improve our understanding of the renal function in heath and diseases. The presented in this article prospect on renal aquaglyceroporin hopefully will stimulate future research in both basic and clinical fields.

Immunohistochemical identification of aquaporin 2 in the kidneys of young beef cattle.

Aquaporin 2 (AQP2) is a small, integral tetrameric plasma membrane protein that is expressed in mammalian kidneys. The specific constitution of this protein and its selective permeability to water means that AQP2 plays an important role in hypertonic urine production. Immunolocalization of AQP2 has been studied in humans, monkeys, sheep, dogs, rabbits, rats, mice and adult cattle. We analyzed the expression of AQP2 in kidneys of 7-month-old Polish-Friesian var. black and white male calves. AQP2 was localized in the principal cells of collecting ducts in medullary rays penetrating the renal cortex and in the collecting ducts of renal medulla. AQP2 was expressed most strongly in the apical plasma membrane, but expression was observed also in the intracellular vesicles and basolateral plasma membrane. Our study provides new information concerning the immunolocalization of AQP2 in calf kidneys.

Blood plasma protein and lipid profile changes in calves during the first week of life.

The present study was undertaken to determine blood plasma protein and lipid profile changes in healthy Polish Holstein-Fresian calves of Black-and-White variety. Blood was drawn immediately after birth, before first colostrum intake and at the 3rd, 6th, 12th, 24th, 36th, 48th and 72nd hour of life. Subsequent four blood samples were collected at 24 hour intervals until the 7th day of life. Plasma proteins within the isoelectric point ranging from 3.0 to 10.0 were separated using high resolution two-dimensional electrophoresis. Among the 74 protein spots detected and analyzed, 16 were significantly altered during the first week of life. Differentially expressed spots were excised from the gels and subjected to peptide mass fingerprinting using MALDI-TOF MS. In total, 12 spots were successfully identified, which correspond to three proteins, namely: apolipoprotein A-I, apolipoprotein A-IV and fibrinogen gamma-B chain. A gradual increase in plasma triglyceride, total cholesterol, HDL and LDL cholesterol values was shown during the first seven days of calves life. The lowest concentration of these indicators were observed at birth and was followed by a rapid increase during the first week of postnatal life. These changes appear to be related to the transition in energy sources, from a maternal nutrient supply comprising mainly carbohydrates and amino acids to a diet which was rich in fat--colostrum and milk. This was reflected by the intense up-regulation of plasma proteins related with lipid transport and lipoprotein metabolism during the first week of life.

Urinary excretion of low molecular weight proteins in goats during the neonatal period.

Urinary protein excretion occurs in neonates of many animal species, as well as in human neonates. However, the incidence, dynamics, and mechanism of proteinuria have not been unambiguously explained. The aims of this study were to investigate into excretion of selected protein fractions of molecular weight less than 69 kDa (LMW), evaluation of intensity and dynamics of changes during the first month of kids' life, and an attempt to explain the causes of neonatal proteinuria. The analysis were carried out on 16 kids of White Improved goats, over the period from birth until 30 days of age, using clearance methods. Urine proteins were separated electrophoretically (SDSPAGE), and their concentration and percentage content was determined by densitometric method with the use of archiving and image analysis software. The proteins found in the urine were grouped as HMW, LMW and albumin. For six fractions of LMW proteins, excretion rates and percentage content of the urinary total LMW protein pool were calculated. It has been demonstrated that neonatal proteinuria in goat kids is associated with a high level of excretion of proteins of lower molecular weight than albumin (69 kDa). A strong dynamics of changes in excretion of particular LMW protein fractions with age was observed, which may imply not only an increased permeability of glomerular filtration barrier, especially over the first days of life, but also a selectivity of reabsorption mechanisms in the nephrons. An increased permeability of glomerular filtration barrier for proteins during the first days of life may represent the adaptive mechanism for removal of protein excess from the organism. The urinary LMW protein pool may also contain proteins resulting from the hydrolysis in the tubular cells.

Cells of different tissues for in vitro and in vivo studies in toxicology: Compilation of isolation methods.

An advantage of using freshly isolated intact cells of different organs in toxicology is that they reflect more closely the in vivo situation than do long-term cultures. In vitro, primary cells provide the possibility of determining cell-specific xenobiotic metabolism, in the absence of artificial extracellular activation systems, which may result in cytotoxic and genotoxic effects. After in vivo exposure of animals to xenobiotics, isolated primary cells can be studied to elucidate toxicokinetic effects. In the review presented here, selected methods are described for isolating cells with high viability from pig liver and avian embryonic liver, and from the nasal cavity, lungs, kidneys, gastro-intestinal tract, urinary bladder, testes and thymus of the rat. Two techniques for preparing rat lymphocytes are also described. Cell isolation may be initiated with an in situ perfusion to clear the organ of blood. Steps to loosen cell-to-cell contacts and to digest the intercellular connective material may then follow. Also, in situ digestion may be performed, as described for the epithelial cells from different mucosal tissues. Following initial digestion, a single-cell suspension is prepared by tissue mincing and a second digestive step with proteolytic enzymes. Frequently used digestive enzymes are collagenase (types I, IV and P; from Clostridium histolyticum), trypsin and proteinase K. Follow-up filtration is usually required to remove undigested material. The quantities and viabilities of the harvested cells vary with the organ of choice and the procedure used; the values obtained are stated.