Effect of Dipeptides on In vitro Maturation, Fertilization and Subsequent Embryonic Development of Porcine Oocytes.

The effects of amino acids and dipeptides on in vitro production of porcine embryos and accumulation of ammonia in culture medium during developmental stages were examined in this study. The maturation, fertilization and development of embryonic cultures were performed in modified Tissue culture medium (mTCM)-199 supplemented with 10% (v/v) porcine follicular fluid, modified Tyrode's albumin lactate pyruvate (mTALP) medium, and modified North Carolina State University (mNCSU)-23 medium, respectively. In addition, amino acids and dipeptides of different concentrations and combinations were used to treat the embryos.

Selenium and vitamin E improve the in vitro maturation, fertilization and culture to blastocyst of porcine oocytes.

Selenium (Se) and vitamin E (Vit-E), as integral parts of antioxidant systems, play important roles for sperm and embryos in vitro. In this study, the effects of Se and Vit-E on the maturation, in vitro fertilization and culture to blastocysts of porcine oocytes and accumulation of ammonia in the culture medium during different development stages were investigated. The maturation was performed in modified tissue culture medium (mTCM)-199 supplemented with 10% (v/v) porcine follicular fluid, the fertilization medium was modified Tyrode's albumin lactate pyruvate (mTALP), and the embryo culture medium was modified North Carolina State University (mNCSU)-23.

Dietary Karaya Saponin and Rhodobacter capsulatus Exert Hypocholesterolemic Effects by Suppression of Hepatic Cholesterol Synthesis and Promotion of Bile Acid Synthesis in Laying Hens.

This study was conducted to elucidate the mechanism underlying the hypolipidemic action of karaya saponin or Rhodobacter (R.) capsulatus. A total of 40 laying hens (20-week-old) were assigned into four dietary treatment groups and fed a basal diet (as a control) or basal diets supplemented with either karaya saponin, R.

Effect of selenium and vitamin E on acrosome reaction in porcine spermatozoa.

Purpose: Selenium (Se) and vitamin E (Vit-E), as an integral part of antioxidant systems, play an important role in the motility and acrosome reaction (AR) of mammalian spermatozoa. The purpose of this study was to investigate the effect of Se and Vit-E on motility, viability, AR and accumulation of ammonia in the culture medium during different incubation periods in porcine sperm.

Methods: Sperm samples were washed, swum-up and incubated at 37°C for 1 and 3 h in Sp-TALP medium supplemented with sodium selenite (SS), seleon l-methionine (SeMet) and Vit-E in the presence or absence of ammonia.

Metabolism of exogenous fatty acids, fatty acid-mediated cholesterol efflux, PKA and PKC pathways in boar sperm acrosome reaction.

Purpose: For understanding the roles of fatty acids on the induction of acrosome reaction which occurs under association of cholesterol efflux and PKA or PKC pathways in boar spermatozoa, metabolic fate of alone and combined radiolabeled C-oleic acid and H-linoleic acid incorporated in the sperm was compared, and behavior of cholesterol and effects of PKA and PKC inhibitors upon fatty acid-induced acrosome reaction were examined.

Methods: Semen was collected from a Duroc boar, and the metabolic activities of fatty acids in the spermatozoa were measured using radioactive compounds and thin layer chromatography. Cholesterol efflux was measured with a cholesterol determination assay kit.

Effect of relaxin on the decidual cell reaction in the Mongolian gerbil ().

Purpose: Differentiation of endometrial stromal cells into decidual cells occurs during embryo implantation and pregnancy. Recently, it has been reported that relaxin affects the decidualization of cultured human endometrial cells in vitro; however, there has been no study on the decidualization of the Mongolian gerbil (). The authors demonstrated artificially induced decidualization, and the effect of relaxin on decidualization in gerbils.

Karaya root saponin exerts a hypocholesterolemic response in rats fed a high-cholesterol diet.

Different sources of saponins are known to have hypocholesterolemic activity with varying degrees of efficacy. We hypothesize that karaya root saponin would efficiently reduce cholesterol. The aim of this study is to examine the comparative hypocholesterolemic effect of karaya root saponin in rats fed a high-cholesterol diet.

Fatty acid composition of lipids in day 7-13 blastocysts, serum and uterine fluid of rabbits.

Purpose: The fatty acid composition of rabbit blastocysts, blood serum and uterine fluids were analyzed to study embryonic lipid metabolism.

Methods: Embryos were collected from Japanese white rabbits and fatty acids were analyzed by gas chromatograph.

Results: Total amount of fatty acids in blastocysts was higher than that in serum and uterine fluid.

Effect of relaxin and IGF-I on the pre-implantation development of Mongolian gerbil () embryos in vitro.

Purpose: Both relaxin and insulin-like growth factor (IGF) are members of the insulin super family. This study aimed to investigate the effect of relaxin and IGF-I on the pre-implantation of Mongolian gerbil of blastocyst development in vitro.

Methods: Blastocysts and eight-cell stage embryos were collected from female gerbils.

Effect of amino acids and dipeptides on the acrosome reaction and accumulation of ammonia in porcine spermatozoa.

The present study was designed to investigate the effect of amino acids and their dipeptides in the medium related to the urea cycle on the motility, viability, acrosome reaction (AR) and accumulation of ammonia in the medium over different incubation periods in porcine spermatozoa and to assess the utilization of glucose. Porcine spermatozoa were washed, swim-up and incubated at 37°C for 0-4 h in mTALP medium supplemented with 75-600 µmol/L ammonia. Amino acids (1.

Effects of relaxin and IGF-I on capacitation, acrosome reaction, cholesterol efflux and utilization of labeled and unlabeled glucose in porcine spermatozoa.

Relaxin and insulin-like growth factor (IGF)-I have pronounced effects on the male and female reproductive tracts. The aim of this study was to investigate the effects of relaxin and IGF-I on the motility, capacitation, acrosome reaction, cholesterol efflux and utilization of glucose in porcine spermatozoa. Swim-up separated spermatozoa that had been washed twice were incubated at 37°C for 1 or 4 h in modified Tyrode's albumin lactate pyruvate (mTALP) medium supplemented without (control) or with relaxin (20 ng/mL) or IGF-I (20 ng/mL) or both (10 + 10 ng/mL).

Effect of fatty acids on boar sperm motility, viability and acrosome reaction.

The present study was undertaken to determine which fatty acids improve motility, viability, and increase acrosome reaction (AR) in boar spermatozoa. Boar spermatozoa were washed, swum-up and incubated at 37°C for 4 h in TALP medium supplemented with myristic, palmitic, stearic, lignoceric, oleic, linoleic, arachidonic, docosahexaenoic and palmitoleic acid. Sperm motility, viability and AR were evaluated during 4 h of incubation.

Effect of amino acids and dipeptides on accumulation of ammonia in the medium during maturation and fertilization of porcine oocytes.

The present study was designed to investigate the effect of amino acids and their dipeptides on the accumulation of ammonia in the medium during maturation (IVM) and fertilization (IVF) of porcine oocytes. The IVM and IVF media were modified North Carolina State University-37 solution and modified Tyrode's albumin lactate pyruvate, respectively. Porcine oocytes were matured in IVM medium containing 75-2400 µmol ammonia.

Spermatogenesis in immature mammals.

Mammalian spermatogenesis has been studied extensively as a prime theme of male reproductive biology, especially for germ cell production, fertilization and development. Investigation of spermatogenesis has provided us with the opportunity to both study the male germ line stem cells and generate the transgenic animals. Spermatogenesis is conducted in the seminiferous tubules, which end in the rete testis.

Effect of fatty acids bound to bovine serum albumin-V on acrosome reaction and utilization of glucose in boar spermatozoa.

The present study has been designed with the objective of determining if fatty acids bound to bovine serum albumin-V (BSA-V) can improve motility, viability, and increase acrosome reaction (AR) and utilization of glucose in boar spermatozoa. Boar spermatozoa were washed, swum-up and incubated at 37°C for 6 h in TALP medium supplemented with fatty acids bound to bovine serum albumin fraction V (BSA-V), fatty acid free BSA (BSA-FAF), polyvinyl alcohol + main fatty acids bound to BSA-V (PVA + FA) and PVA. Sperm motility, viability, AR, and the incorporation and oxidation of C-glucose were evaluated during 6 h of incubation.

Effect of fructose on motility, acrosome reaction and fertilization capability of boar spermatozoa.

The present study was carried out to investigate the effects of fructose supplementation in glucose containing mTALP medium on motility, acrosome reaction and fertilization capability of boar spermatozoa. Boar spermatozoa were preincubated, swum-up, resuspended and then incubated for 6 h in mTALP medium supplemented with 0, 0.5, or 1.

Effect of relaxin on acrosome reaction and utilization of glucose in boar spermatozoa.

Relaxin is a peptide hormone found in seminal plasma that has a physiological influence on sperm motility in some species. There are no reports on the effect of relaxin on acrosome reaction and utilization of glucose in boar spermatozoa. In this study, to investigate the effects of relaxin on sperm motility, acrosome reaction, and incorporation and oxidation of labeled glucose, boar spermatozoa were washed and preincubated for swim-up and then incubated (0-6 h) with 0, 20, or 40 ng/ml relaxin in mTALP medium.

Effect of relaxin on motility, acrosome reaction and viability of cryopreserved boar spermatozoa.

Relaxin has an important role in stimulating motility and the acrosome reaction (AR) of fresh boar spermatozoa. The objective of the present study was to determine whether relaxin can improve the motility, AR and viability of cryopreserved boar spermatozoa.  Cryopreserved boar spermatozoa were thawed, washed and incubated at 37°C for 4 h in modified Beltsville thawing solution supplemented with 0, 20 or 40 ng/mL relaxin.

Effect of relaxin on in vitro fertilization of porcine oocytes.

Porcine relaxin is a peptide hormone belonging to the insulin super family that has a variety of biological functions. The present experiment was designed to investigate the effects of relaxin on sperm function and on in vitro fertilization (IVF) of porcine oocytes. Porcine spermatozoa were washed, swum-up, and incubated for 1-4 h in mTALP medium supplemented with 0, 20 or 50 ng/ml porcine relaxin.

Evaluation of testicular toxicity and sperm morphology in rats treated with methyl methanesulphonate (MMS).

Methyl methanesulphonate (MMS), a potent alkylating agent and testicular toxicant, was orally administered to rats for 5 days at 40 mg/kg. During the recovery period of up to 5 weeks, males were evaluated for testicular toxicity and sperm morphology. The 5-week recovery period were designated as follows: Day 1 (the day after final treatment); Week 1, Week 2, Week 3, Week 4 and Week 5 (1, 2, 3, 4 and 5 weeks after final treatment).

A time-course characterization of male reproductive toxicity in rats treated with methyl methanesulphonate (MMS).

Methyl methanesulphonate (MMS), a potent alkylating agent and testicular toxicant, was orally administered to rats for 5 days at doses of 20, 30, and 40 mg/kg. During the recovery period of 5 weeks, males were evaluated for multiple endpoints such as organ weights, fertility, and sperm parameters. The 5-week recovery periods are designated as follows: Day 1 (1 day after final treatment); Week 1, Week 2, Week 3, Week 4, and Week 5 (first, second, third, fourth, and fifth week after final treatment).

Development of Mongolian gerbil embryos in chemically defined media: effects of osmolarity, glucose and phosphate.

Mongolian gerbil 2-cell embryos were cultured in modified M16. When osmolarity of the medium with 5.0 mmol glucose l(-1) was varied by adjusting the amount of NaCl added, 2-cell embryos at 280, 290, 300 and 310 mOsmol developed to the 8- and 16-cell stages.

Genetic analysis for diabetes in a new rat model of nonobese type 2 diabetes, Spontaneously Diabetic Torii rat.

The Spontaneously Diabetic Torii (SDT) rat has recently been established as a new rat model of nonobese type 2 diabetes. In this study, we characterized diabetic features in SDT rats, and performed quantitative trait locus (QTL) analysis for glucose intolerance using 319 male (BNxSDT)xSDT backcrosses. Male SDT rats exhibited glucose intolerance at 20 weeks, and spontaneously developed diabetes with the incidence of 100% at 38 weeks, and glucose intolerance is well associated with the development of diabetes.