105 Increasing fertility of interspecific hybrid males using biotechnological approaches

The results of AI depend on many factors, with the quality of semen being one of the most important. Not all male hybrids can meet the requirements for semen quality, because they often have reduced fertility following cryopreservation. Thus, it is necessary to improve semen processing before use in AI. The aim of the study was to evaluate the effectiveness of using the “swim-up” flotation method to improve sperm quality of hybrid males of the Ovis genus. Semen from interspecific hybrid rams (1/4 Argali×3/4 Romanov, n=15; 1/8 Argali×7/8 Romanov, n=15) was freshly obtained, frozen–thawed, and processed by the swim-up method. Evaluation of sperm motility was determined using computer-assisted semen analysis. Statistical analysis was performed using SPSS vs.15.0 (ANOVA and t-test; SPSS Inc.). Semen was collected during the breeding season (October–December) via artificial vagina. Assessment of acrosome integrity was determined using differential staining with a Diachem diff-quick kit (NPF ABRIS+). The degree of sperm DNA fragmentation was determined using the acridine-orange test. The sperm freezing/thawing cycle was accompanied by sperm damage and an increase in the proportion of immobile sperm from 10 to 58%, with non-progressive movement increasing from 9 to 19.3%. The number of spermatozoa with abnormal morphology doubled, and the DNA fragmentation index increased from 16 to 26%. Use of the swim-up procedure allowed us to sort progressively motile spermatozoa. The content of progressively motile spermatozoa in the samples obtained from the supernatant was 86%, which was 2.3 times higher than in frozen–thawed sperm (P≤0,01). The obtained results show the effective use of the swim-up procedure to determine the quality of semen in hybrid rams. These studies were carried out with financial support from the Russian Science Foundation, grant No. 18-16-00079 and the Ministry of Science and Higher Education of the Russian Federation.

104 The effect of interspecific hybridization on the development of testes in genus Ovis males

Interspecific hybrids, especially males, are sterile or have reduced fertility. The structure and development of reproductive organs is species-specific. The study of development stages, morphology and biometric parameters in the male testes, the characterisation of species features, and the development of assisted reproductive technologies is of great importance. The aim of this research was to study morphometric parameters of the testes of interspecific hybrids of Argali with sheep of the Romanov breed compared with the original Romanov breed. The objects of research were purebred males of the Romanov breed (n=8) and hybrid males with the following genotypes: 1/4 Argali×3/4 Romanov (Group I, n=10), 1/8 Argali×7/8 Romanov (Group II, n=12). The collection of testes from purebred and hybrid animals was carried out at castration (age=12 months). Testicular tissue was fixed in Bouin’s solution. The following metrics were evaluated: weight and morphometric parameters of the testis, diameter of the seminiferous tubules, and the number of spermatogenic cells in the seminiferous tubule. Statistical analysis (comparison between groups with t-test and ANOVA) was performed using SPSS vs.15.0 (SPPS Inc.). The weight of testes in purebred Romanov males averaged 393±41g. In hybrid animals from groups I and II, this indicator was lower compared with that of purebred animals, by 58% and 41% (P<0.01), respectively. The average circumference of the testes in purebred animals and hybrids of groups I and II was 26±2, 19±3 and 20±3cm. The diameter of the seminiferous tubules in purebred animals and in hybrids of groups I and II was 215±3, 121±2 and 170±6µm, respectively. The number of spermatogenic cells inside the seminiferous tubules affects their size. In purebred animals, this value reached 90±3 cells. Hybrid animals in Groups I and II were inferior to their purebred peers in the number of spermatogenic cells in the seminiferous tubules by 31% (P<0.01) and 9%, respectively. The obtained results indicate the influence of individual characteristics of males on testicular morphology, including the number of spermatogenic cells in the seminiferous tubules. The studies were carried out with financial support from the Russian Science Foundation, grant No. 18-16-00079 and the Ministry of Science and Higher Education of the Russian Federation.

INTERRELATION OF THE GENE 4DKN1A (RS 1801270) POLYMORPHIC STATE AND LEVEL OF DEVELOPMENT OF CARIES IN CHILDREN WITH DOWN SYNDROME

Study is devoted for rs1801270 polymorphism of CDKN1A gene due to the level of intensity of caries development in children with Down syndrome. The full development of oral cavity organs is ensured through a complex of genes whose protein products control different stages of this difficult process. Changes in gene structure, as well as disturbance of their expression may lead to abnormalities of development of teeth and periodontal tissues. Analysis of the polymorphism of CDKN1A gene Ser31Arg in children living in Kharkiv region has shown that the frequency of genotypes and alleles corresponds to the theoretically expected distribution by Hardy-Weinberg in the core (χ2=0.12) and control (χ2=1.29) groups. There is no significant differences in the frequency of alleles of CDKN1A gene in the group of healthy children and children with Down syndrome (p=0.978). There is an association of heterozygous option C/A of the studied marker Ser31Arg of CDKN1A gene with the level of intensity of caries development (by Leus) in children with Down syndrome under 10 years old.

Reduced glutathione increases quercetin stimulatory effects on HDL- or apoA1-mediated cholesterol efflux from J774A.1 macrophages

In our in vitro study, we analyzed the effects of incubation of J774A.1 macrophages with reduced glutathione (GSH) and quercetin on the extent of cellular cholesterol efflux by high-density lipoprotein (HDL) or apolipoprotein A1 (apoA1). This combination was the most potent one among other exogenous and endogenous antioxidant combinations, since it significantly increased the extent of HDL-mediated cholesterol efflux from macrophages by 47% versus control cells, whereas quercetin (20 μM) or GSH (200 μM) alone increased it by only 37% or 17%, respectively. Similarly, apoA1-mediated cholesterol efflux was increased by 11% or 22% in quercetin or quercetin + GSH-treated cells, respectively, versus control cells. These stimulatory effects were noted only after 20 h of cell incubation. The combination of quercetin + GSH demonstrated high scavenging capacity of free radicals versus quercetin or GSH alone. In addition, quercetin + GSH significantly decreased macrophage oxidative stress as measured by the scavenging capacity of free radicals in the cells, the formation of reactive oxygen species, and the levels of cellular glutathione and lipid peroxides. There was no significant effect of quercetin + GSH on cellular HDL binding, on ATP-binding cassette A1 (ABCA1) activity, or on ABCG1 messenger RNA (mRNA) levels. In contrast, mRNA levels for ABCA1 and peroxisome proliferator-activated receptor alpha (PPARα) were both significantly increased by 89% and 93%, respectively, in quercetin + GSH-treated cells versus control cells. Quercetin alone increased the mRNA levels for ABCA1 or PPARα by 42% or 77%, respectively, whereas GSH alone increased it by 22% or 28%, respectively. Mass spectra analysis revealed that oxidized quercetin reacts with GSH to form a new adduct product. We thus conclude that the stimulatory effects of quercetin + GSH on apoA1- or HDL-mediated macrophage cholesterol efflux are related to the ability of GSH to preserve quercetin in its reduced form.

Monocyte-macrophage membrane possesses free radicals scavenging activity: stimulation by polyphenols or by paraoxonase 1 (PON1)

In the current study, we analysed free radicals scavenging activity of monocytes-macrophages in the absence or presence of antioxidants such as polyphenols or paraoxonase 1 (PON1). THP-1 human monocytic cell line, murine J774A.1 macrophages, as well as human primary monocytes have the capability to scavenge free radicals, as measured by the 1-diphenyl-2-picryl-hydrazyl (DPPH) assay. This effect (which could be attributed to the cell's membrane) was cell number and incubation time dependent. Upon incubation of J774A.1 macrophages with acetylated LDL (Ac-LDL), with VLDL, or with the radical generator, AAPH, the cells' lipid peroxides content, and paraoxonase 2 (PON2) activity were significantly increased. While non-treated cells decreased DPPH absorbance by 65%, the Ac-LDL-, VLDL- or AAPH-treated cells, decreased it by only 33%, 30%, or 45%, respectively. We next analysed the effect of J774A.1 macrophage enrichment with antioxidants, such as polyphenols or PON1 on the cells' free radicals scavenging activity. Non-treated cells decreased DPPH absorbance by 50%, whereas vitamin E-, punicalagin- or PJ-treated cells significantly further decreased it, by 75%. Similarly, in PON1-treated cells DPPH absorbance was further decreased by 63%, in association with 23% increment in PON1 catalytic activity. In cells under oxidative stress [treated with AAPH-, or with oxidized LDL], PON1 activity was decreased by 31% or 40%, as compared to the activity observed in PON1 incubated with non-treated cells. We conclude that monocytes-macrophages possess free radicals scavenging activity, which is decreased under atherogenic conditions, and increased upon cell enrichment with potent antioxidants such as nutritional polyphenols, or PON1.

249 THE DIRECT AND CUMULUS-MEDIATED EFFECTS OF PROLACTIN ON BOVINE OOCYTES

Prolactin (PRL) is an important regulator of female reproduction, as indicated using PRL receptor knockout mice (Bole-Feysot C et al. 1998 Endocrinol. Rev. 19, 225–268). The presence of PRL receptors or their mRNA has been shown in different follicular compartments of various mammalian species, including oocytes of sheep and mice (Picazo RA et al. 2004 Reproduction 128, 545–553; Kiapekou E et al. 2005 Reprod. Biomed. Online 10, 339–346). The aim of the present study was to characterize the direct and cumulus-mediated pathways of PRL signaling into bovine oocytes. The expression of PRL receptor mRNA in follicular cells was detected by reverse transcription polymerase chain reaction (RT-PCR) analysis. For oocytes, nested PCR was used. In addition, a total of 707 COC and 689 denuded oocytes (DO) from follicles 2 to 8 mm in diameter were cultured for 6 h (COC), 8 h (DO), or 24 h (COC and DO) in the presence or absence of 50 ng mL–1 bovine PRL (20 IU mg–1; Research Center for Endocrinology, Moscow, Russia). The following systems for COC and DO culture were used: (1) TCM-199 containing 10% fetal calf serum (system 1) and (2) DMEM containing 10 U mL–1 pregnant mare’s serum gonadotropin (PMSG), 5 U mL–1 hCG (Intervet Scandinavia, Copenhagen, Denmark), and 5% estrous cow serum (system 2). The nuclear status of oocytes was evaluated by Tarkowski’s cytogenetic method. After IVM in system 2, a portion of the oocytes (348 COC and 311 DO) underwent IVF and IVC, and the embryo development was tracked until the blastocyst stage. All treatments were repeated 4 to 7 times. Results were expressed as mean ± SEM. Arcsine-transformed data were analyzed by two-way ANOVA. Messenger RNA expression of long and short isoforms of PRL receptor was revealed in both bovine oocytes and cumulus cells. In system 1, PRL raised the rate of DO remaining at the diplotene stage by 8 h of culture (from 32.6 ± 3.0 to 47.5 ± 4.7%, P < 0.05), whereas there was no effect of PRL on the meiotic resumption in COC. By contrast, the hormone exerted a stimulatory action on the meiotic progression in the presence of cumulus cells by increasing the proportion of oocytes reaching the telophase I or metaphase II stages during 24 h of maturation (from 61.9 ± 1.2 to 73.5 ± 0.9%, P < 0.05). In system 2, PRL did not affect nuclear maturation of either cumulus-enclosed or cumulus-free oocytes, with the maturation rate varying between 93.9 ± 2.7 and 95.2 ± 2.4% (COC) and between 85.6 ± 3.0 and 83.0 ± 4.0% (DO). When added to IVM system 2, PRL raised the cleavage and blastocyst rates only in the case of COC (from 72.2 ± 2.4 to 80.2 ± 2.1%, P < 0.05, and from 20.5 ± 3.6 to 40.9 ± 4.2%, P < 0.01, respectively). These findings suggest functioning of the direct and cumulus-mediated pathways of PRL signaling into bovine oocytes, with the hormone affecting meiosis via both pathways. We thank A. D. Roed for expert technical assistance with IVF and IVC. This research was supported in part by RFBR (project no. 07-04-01485). I.L. was the recipient of an Erasmus Mundus fellowship.

Pomegranate juice flavonoids inhibit low-density lipoprotein oxidation and cardiovascular diseases: studies in atherosclerotic mice and in humans

The beneficial health effects attributed to the consumption of fruit and vegetables are related, at least in part, to their antioxidant activity. Of special interest is the inverse relationship between the intake of dietary nutrients rich in polyphenols and cardiovascular diseases. This effect is attributed to polyphenols' ability to inhibit low-density lipoprotein (LDL) oxidation, macrophage foam cell formation and atherosclerosis. Pomegranate polyphenols can protect LDL against cell-mediated oxidation via two pathways, including either direct interaction of the polyphenols with the lipoprotein and/or an indirect effect through accumulation of polyphenols in arterial macrophages. Pomegranate polyphenols were shown to reduce the capacity of macrophages to oxidatively modify LDL, due to their interaction with LDL to inhibit its oxidation by scavenging reactive oxygen species and reactive nitrogen species and also due to accumulation of polyphenols in arterial macrophages; hence, the inhibition of macrophage lipid peroxidation and the formation of lipid peroxide-rich macrophages. Furthermore, pomegranate polyphenols increase serum paraoxonase activity, resulting in the hydrolysis of lipid peroxides in oxidized lipoproteins and in atherosclerotic lesions. These antioxidative and antiatherogenic effects of pomegranate polyphenols were demonstrated in vitro, as well as in vivo in humans and in atherosclerotic apolipoprotein E deficient mice. Dietary supplementation of polyphenol-rich pomegranate juice to atherosclerotic mice significantly inhibited the development of atherosclerotic lesions and this may be attributed to the protection of LDL against oxidation.

White wine with red wine-like properties: increased extraction of grape skin polyphenols improves the antioxidant capacity of the derived white wine

Lower antioxidant activity in white wines in comparison to red wines lies in the low grape-skin-derived polyphenol content. This paper reports the analysis of the antioxidant capacities of white wine samples obtained along two different processing procedures directed to enrich the wine with polyphenols. White wine samples derived from whole squeezed grapes stored for increasing periods of time (up to 18 h) contained increasing concentrations of polyphenols (from 0.35 to 0.55 mmol/L) and, in parallel, exhibited increased capacity to scavenge free radicals and to inhibit copper ion-induced low-density lipoprotein (LDL) oxidation. However, addition of increasing concentrations of alcohol (up to 18%) to the whole squeezed grapes remarkably augmented the extraction of grape skin polyphenols into the wine up to 1.25 mmol/L, resulting in an increased capacity of the wine to scavenge free radicals and to inhibit LDL oxidation, to an extent similar to that of red wine. The extent of LDL oxidation inhibition was directly related to the wine polyphenolic content (r = 0.986). It is concluded that processing white wine by imposing a short period of grape skin contact in the presence of alcohol leads to extraction of grape skin polyphenols and produces polyphenol-rich white wine with antioxidant characteristics similar to those of red wine.

Calorimetry a method to be used to characterise pyrolytically decarboxylated bicarbonate and assess its stability at elevated humidities

Microcalorimetry was used to characterise bicarbonate after treatment at high temperatures. By measuring the heat flow from a sample of bicarbonate at 100% relative humidity, the net exothermic contribution could be used to estimate the fraction of pyrolytically formed Na(2)CO(3). The enthalpy value corresponding to the heat of solution of Na(2)CO(3) was also applicable to a physical mixture of NaHCO(3)/Na(2)CO(3). However, from the characteristic peaks of the heat flow versus time curve, pyrolytically formed Na(2)CO(3) could be distinguished from that present in the physical mixture. The different bicarbonate batches of varying degree of pyrolytic decarboxylation were also observed at an elevated relative humidity of 54%. From these measurements it could be inferred that a decarboxylation of up to 4.5% could be allowed without any significant effect on the stability of bicarbonate at 54%.

Pomegranate juice consumption reduces oxidative stress, atherogenic modifications to LDL, and platelet aggregation: studies in humans and in atherosclerotic apolipoprotein E-deficient mice

BACKGROUND

Dietary supplementation with nutrients rich in antioxidants is associated with inhibition of atherogenic modifications to LDL, macrophage foam cell formation, and atherosclerosis. Pomegranates are a source of polyphenols and other antioxidants.

OBJECTIVE

We analyzed, in healthy male volunteers and in atherosclerotic apolipoprotein E-deficient (E(0)) mice, the effect of pomegranate juice consumption on lipoprotein oxidation, aggregation, and retention; macrophage atherogenicity; platelet aggregation; and atherosclerosis.

DESIGN

Potent antioxidative effects of pomegranate juice against lipid peroxidation in whole plasma and in isolated lipoproteins (HDL and LDL) were assessed in humans and in E(0) mice after pomegranate juice consumption for </=2 and 14 wk, respectively.

RESULTS

In humans, pomegranate juice consumption decreased LDL susceptibility to aggregation and retention and increased the activity of serum paraoxonase (an HDL-associated esterase that can protect against lipid peroxidation) by 20%. In E(0) mice, oxidation of LDL by peritoneal macrophages was reduced by up to 90% after pomegranate juice consumption and this effect was associated with reduced cellular lipid peroxidation and superoxide release. The uptake of oxidized LDL and native LDL by mouse peritoneal macrophages obtained after pomegranate juice administration was reduced by 20%. Finally, pomegranate juice supplementation of E(0) mice reduced the size of their atherosclerotic lesions by 44% and also the number of foam cells compared with control E(0) mice supplemented with water.

CONCLUSION

Pomegranate juice had potent antiatherogenic effects in healthy humans and in atherosclerotic mice that may be attributable to its antioxidative properties.

Lycopene synergistically inhibits LDL oxidation in combination with vitamin E, glabridin, rosmarinic acid, carnosic acid, or garlic

Several lines of evidence suggest that oxidatively modified low-density lipoprotein (LDL) is atherogenic, and that atherosclerosis can be attenuated by natural antioxidants, which inhibit LDL oxidation. This study was conducted to determine the effect of tomato lycopene alone, or in combination with other natural antioxidants, on LDL oxidation. LDL (100 microg of protein/ml) was incubated with increasing concentrations of lycopene or of tomato oleoresin (lipid extract of tomatoes containing 6% lycopene, 0.1% beta-carotene, 1% vitamin E, and polyphenols), after which it was oxidized by the addition of 5 micromol/liter of CuSO4. Tomato oleoresin exhibited superior capacity to inhibit LDL oxidation in comparison to pure lycopene, by up to five-fold [97% vs. 22% inhibition of thiobarbituric acid reactive substances (TBARS) formation, and 93% vs. 27% inhibition of lipid peroxides formation, respectively]. Because tomato oleoresin also contains, in addition to lycopene, vitamin E, flavonoids, and phenolics, a possible cooperative interaction between lycopene and such natural antioxidants was studied. A combination of lycopene (5 micromol/liter) with vitamin E (alpha-tocopherol) in the concentration range of 1-10 micromol/liter resulted in an inhibition of copper ion-induced LDL oxidation that was significantly greater than the expected additive individual inhibitions. The synergistic antioxidative effect of lycopene with vitamin E was not shared by gamma-to-cotrienol. The polyphenols glabridin (derived from licorice), rosmarinic acid or carnosic acid (derived from rosemary), as well as garlic (which contains a mixture of natural antioxidants) inhibited LDL oxidation in a dose-dependent manner. When lycopene (5 micromol/liter) was added to LDL in combination with glabridin, rosmarinic acid, carnosic acid, or garlic, synergistic antioxidative effects were obtained against LDL oxidation induced either by copper ions or by the radical generator AAPH. Similar interactive effects seen with lycopene were also observed with beta-carotene, but, however, to a lesser extent of synergism. Because natural antioxidants exist in nature in combination, the in vivo relevance of lycopene in combination with other natural antioxidants was studied. Four healthy subjects were administered a fatty meal containing 30 mg of lycopene in the form of tomato oleoresin. The lycopene concentration in postprandial plasma was elevated by 70% in comparison to plasma obtained before meal consumption. Postprandial LDL isolated 5 hr after meal consumption exhibited a significant (p < 0.01) reduced susceptibility to oxidation by 21%. We conclude that lycopene acts synergistically, as an effective antioxidant against LDL oxidation, with several natural antioxidants such as vitamin E, the flavonoid glabridin, the phenolics rosmarinic acid and carnosic acid, and garlic. These observations suggest a superior antiatherogenic characteristic to a combination of different natural antioxidants over that of an individual one.