In vitro maturation in synthetic oviductal fluid increases gene expression associated with quality and lipid metabolism in bovine oocytes

Traditionally, in vitro oocyte and embryo culture progresses through a series of varying culture medium. To investigate simplifying the in vitro production of bovine cumulus-oocyte complexes (COCs), this study used synthetic oviductal fluid (SOF) supplemented with conjugated linoleic acid (CLA). Special interest was placed on gene expression linked to lipid metabolism and oocyte maturation. COCs were matured in different media: Medium 199 (M199 group), M199 with 100 μM CLA (M199 + CLA group), SOF (SOF group), and SOF with 100 μM CLA (SOF + CLA group). COCs matured with SOF showed a higher relative abundance of mRNA of quality indicators gremlin 1 (GREM1) and prostaglandin-endoperoxide synthase 2 (PTGS2) in oocytes, and GREM1 in cumulus cells compared with in the M199 group. SOF medium COCs had a higher relative abundance of fatty acid desaturase 2 (FADS2) compared with the M199 group, which is essential for lipid metabolism in oocytes. Furthermore, the abundance of stearoyl-coenzyme A desaturase 1 (SCD1) in oocytes matured with SOF was not influenced by the addition of CLA, whereas the relative abundance of SCD1 was reduced in M199 medium with CLA. We concluded that maturation in SOF medium results in a greater abundance of genes linked to quality and lipidic metabolism in oocytes, regardless of the addition of CLA.

Different nutritional systems influence the tenderness and lipid oxidation of ewe lamb meat without altering gene expression

Feeding is a determining factor in the various characteristics of sheep meat and animal performance, the objectives were to evaluate the effect of supplementation of ewe lambs finished in different nutritional planes on the gene expression of CASP3, CAPN1, CAPN2 and CAST and its possible association with meat quality. Samples of the Longissimus lumborum muscle of 24 ewe lambs were used, distributed in 3 groups (n=8): P (pasture), PS (pasture and supplement) and F (feedlot). Physicochemical analyses were performed for centesimal analysis, pH, lipid oxidation, Warner-Bratzler shear force and RT-qPCR for the analysis of relative gene expression of the following genes: CASP3, CAPN1, CAPN2 and CAST. There is an increase in daily weight gain and ethereal extract values in the meat of confined animals, due to the greater energy intake in the nutrition of these animals. Animals kept only on pasture have lower lipid oxidation in meat than other treatments because of the lower percentage of lipids. The Warner-Bratzler shear force is considerably higher in the meat of animals kept only on pasture but is still considered tender. The different nutritional systems do not interfere with the gene expression of CASP3, CAPN1, CAPN2 and CAST in ewe lambs.

An approach to uncover the relationship between 17b-estradiol and ESR1/ESR2 ratio in the regulation of canine corpus luteum

The canine corpus luteum (CL) is able to synthetise, activate and deactivate 17b-estradiol (E2) and also expresses nuclear estrogen receptors in a time-dependent manner during diestrus. Nevertheless, we are still missing a better comprehension of E2 functions in the canine CL, especially regarding the specific roles of estrogen receptor alpha (ERa) and ERb, encoded by ESR1 and 2, respectively. For that purpose, we analyzed transcriptomic data of canine non-pregnant CL collected on days 10, 20, 30, 40, 50 and 60 of diestrus and searched for differentially expressed genes (DEG) containing predicted transcription factor binding sites (TFBS) for ESR1 or ESR2. Based on biological functions of DEG presenting TFBS, expression of select transcripts and corresponding proteins was assessed. Additionally, luteal cells were collected across specific time points during diestrus and specificity of E2 responses was tested using ERa and/or ERb inhibitors. Bioinformatic analyses revealed 517 DEGs containing TFBS, from which 67 for both receptors. In general, abundance of predicted ESR1 targets was greater in the beginning, while abundance of ESR2 targets was greater in the end of diestrus. ESR1/ESR2 ratio shifted from an increasing to a decreasing pattern from day 30 to 40 post ovulation. Specific receptor inhibition suggested an ERa-mediated positive regulation of CL function at the beginning of diestrus and an ERb-mediated effect contributing to luteal regression. In conclusion, our data points toward a broad spectrum of action of E2 and its nuclear receptors, which can also act as transcription factors for other genes regulating canine CL function.

High-intensity interval training attenuates the effects caused by arterial hypertension in the ventral prostate

BACKGROUND

The prostatic effects induced by arterial hypertension is very controversial and its mechanism is unclear. High-intensity interval training (HIIT) is an exercise considered to be hypotensive. The objective of this work was to investigate the molecular, biochemical, and morphological effects of 8 weeks of HIIT in the prostatic tissue of spontaneously hypertensive rats (SHR).

METHODS

Twenty male SHR rats, 51.4 weeks old, were used. The SHR animals were divided into two groups: spontaneously sedentary hypertensive and spontaneously hypertensive submitted to HIIT. We analyze androgens receptor and glucocorticoid receptors in the prostate. Still, we verify effects of the hypertension and HIIT on the physiopathology prostatic, for immunohistochemistry investigated BCL-2, BAX, IGF-1, FAS/CD95, data's inflammatory tumour necrosis factor α, nuclear factor kappa B and interleukin (IL)-6, anti-inflammatory IL-10. The echocardiographic evaluation was performed at the baseline and after the training period.

RESULTS

Arterial hypertension promote high prostatic intraepithelial neoplasia incidence in the prostate, increases IGF-1, BCL-2 (p < 0.05), and inflammatory proteins (p < 0.05). Eight weeks of HIIT training reduced the arterial pressure and increase the concentration of tissue collagen and intracellular glycogen and showed a higher expression of BAX, FAS/CD95, and IL-10 proteins (p < 0.05), coinciding with a lower incidence of lesions and lower prostate weight (p < 0.05) and reduction of the BCL-2 and IGF-1.

CONCLUSION

Our data suggested that arterial hypertension suppressed apoptosis and increased damage prostatic. On other hand, HIIT promotes morphology and function improves in the prostatic environment, inhibited inflammation, and increased apoptosis.

Insulin induces steroidogenesis in canine luteal cells via PI3K-MEK-MAPK

Glucose uptake increases in canine luteal cells under insulin treatment. We hypothesize that insulin also increases luteal cell steroidogenesis. Dogs underwent elective ovariohysterectomy from days 10-60 post ovulation and their corpora lutea (CL) and blood samples were collected. Deep RNA sequencing determined differentially expressed genes in CL; those related to insulin signaling and steroidogenesis were validated in vivo by qPCR and their respective proteins by Western blotting and immunofluorescence. Next, luteal cell cultures were stimulated with insulin with or without inhibition of MAPK14, MAP2K1 and PI3K. Studied proteins except P450 aromatase showed the same expression pattern of coding genes in vivo. The expression of HSD3B and CYP19A1 was higher in insulin-treated cells (P < 0.005). Following respective pathway blockades, the culture medium had decreased concentrations of progesterone (P4) and 17b-estradiol (E2) (P < 0.01). Our results indicate that insulin increases HSD3B and CYP19A1 expression via MAPK and PI3K, and contributes to the regulation of P4 and E2 production in canine luteal cells.

Global transcriptome analysis implicates cholesterol availability in the regulation of canine cyclic luteal function

Considering the key role of the corpus luteum in the regulation of the canine diestrus, the present study aimed to investigate changes in the luteal transcriptome of pseudopregnant dogs (n = 18) from days (D) 10, 20, 30, 40, 50 and 60 post-ovulation. After RNAsequencing was performed, data was analyzed by resorting to several informatic tools. A total of 3300 genes were differently expressed among all samples (FDR < 0.01). By comparing different time points, enriched biological processes as response to estradiol and lipids (D20 vs D10) and intracellular cholesterol transport (D40 vs D60) were observed. Moreover, LXR/RXR (liver X receptor- retinoid X receptor) signaling appeared as an overrepresented pathway in all comparisons. Thus, the expression of 19 genes involved in intracellular cholesterol availability was further evaluated; most were affected by time (P < 0.05). Adding to the deep transcriptomic analysis, presented data implies the importance of cholesterol regulation in luteal physiology of pseudopregnant dogs.

Prebiotics mannan-oligosaccharides accelerate sexual maturity in rats: A randomized preclinical study

Background and Aim:

The prebiotics, mannan-oligosaccharides (MOS), demonstrate the ability to increase probiotic microorganisms and fixation and removal of pathogens associated with chronic systemic inflammation in the digestive system. Inflammatory processes play an important role in modulating the brain-intestinal axis, including maintaining male reproductive function and spermatogenesis and regulating stress. The aim of the present study was to evaluate the action of MOS on testosterone and corticosterone concentrations and the reproductive system development of rats in the growth phase as an animal model.

Materials and Methods:

In total, 128 male rats were used, randomly divided into four experimental groups (n=32): Control; MOS 1; MOS 2; and MOS 3. From each group, eight animals were sacrificed in four experimental moments (14, 28, 42, and 56 days, respectively, moments 1, 2, 3, and 4) and hormonal measurements and histological evaluations were performed.

Results:

The results revealed the effect of diet, MOS, and timing on testicle weight (p<0.05). At moments 3 and 4, the groups supplemented with MOS showed higher concentrations of testosterone and decreased corticosterone levels throughout the experimental period. Groups supplemented with MOS showed an increase in the frequency of relative sperm and sperm scores. The radii of the seminiferous tubules presented a significant statistical effect of the diet, moments, and diet + moment interaction.

Conclusion:

It was concluded that the three different MOS prebiotics brought forward sexual maturity.

Serum Progesterone and Conception Rates in Acyclic Embryo Recipient Mares Using a Bovine Progesterone-Releasing Intravaginal Device

The objective of this study was to quantify serum progesterone levels, uterine features, and pregnancy rates in acyclic, embryo recipient mares using a bovine progesterone-releasing intravaginal device in a commercial embryo transfer (ET) program. The study included 73 recipient mares of unknown breed, aged 3-10 years, weighing 350-500 kg, and kept under an intensive management system on Tifton 85 (Cynodon spp.) pastures with water and mineral salt ad libitum. The horses were divided into two groups: a group with a progesterone-releasing intravaginal device (1 g progesterone, G-IVP4, n = 24) and a control group (G-iP4, n = 49) receiving an injection of 1,500 mg long-acting progesterone. Jugular blood was collected for the G-IVP4 group for subsequent progesterone measurement by radioimmunoassay on three occasions: Day 0 (D0), intravaginal device was placed; Day 5 (D5), day of the ET; and Day 9 (D9), day of pregnancy diagnosis. There was an increase (P < .0001) in serum progesterone levels on D5 and D9 compared with D0 (4.09 ± 0.81 and 6.45 ± 1.03 ng/mL vs. 0.71 ± 0.14 ng/mL). There were no differences among groups in the pregnancy rate (P > .05), with rates of 83.33% and 73.46% for G-IVP4 and G-iP4, respectively. In conclusion, the intravaginal route for absorption of 1 g of progesterone device increased the serum level of progesterone sufficiently to prepare the uterus of acyclic recipient mares for ET, and the conception rate was similar to the standard protocol using long-acting injectable progesterone.

Effects of muscular strength training and growth hormone (GH) supplementation on femoral bone tissue: analysis by Raman spectroscopy, dual-energy X-ray absorptiometry, and mechanical resistance

The aim of the present study was to verify the effects of muscular strength training and growth hormone (GH) supplementation on femoral bone tissue by Raman spectroscopy (Raman), dual-energy X-ray absorptiometry (DXA), and mechanical resistance (F-max) analysis. A total of 40 male Wistar animals, 60 days old, were used. The animals were distributed into four groups: control (C), control with GH (GHC), muscular strength training (T), and muscular strength training with GH (GHT). Blood samples were collected for the quantification of creatine kinase (CK-MB) and the femurs were removed for analysis by Raman, DXA, and F-max. A more pronounced increase in the bone mineral components was verified in the T group, for all the variables obtained by the Raman (calcium, phosphate, amide, and collagen). In addition, for animals submitted to GH supplementation, there was a reduction in the variable bone mineral density (BMD) obtained by the DXA (p < 0.05). Finally, the animals that received GH supplementation presented a higher F-max, but without statistical significance (p > 0.05). It was concluded that animals that received GH supplementation demonstrated a decrease in BMD. In addition, T alone was able to promote increased calcium, phosphate, amide, and collagen compounds in bone tissue.

High final energy of gallium arsenide laser increases MyoD gene expression during the intermediate phase of muscle regeneration after cryoinjury in rats

The aim of this study was to determine the effects of gallium arsenide (GaAs) laser on IGF-I, MyoD, MAFbx, and TNF-α gene expression during the intermediate phase of muscle regeneration after cryoinjury 21 Wistar rats were divided into three groups (n = 7 per group): untreated with no injury (control group), cryoinjury without GaAs (injured group), and cryoinjury with GaAs (GaAs-injured group). The cryoinjury was induced in the central region of the tibialis anterior muscle (TA). The region injured was irradiated once a day during 14 days using GaAs laser (904 nm; spot size 0.035 cm², output power 50 mW; energy density 69 J cm^-2; exposure time 4 s per point; final energy 4.8 J). Twenty-four hours after the last application, the right and left TA muscles were collected for histological (collagen content) and molecular (gene expression of IGF-I, MyoD, MAFbx, and TNF-α) analyses, respectively. Data were analyzed using one-way ANOVA at P < 0.05. There were no significant (P > 0.05) differences in collagen density and IGF-I gene expression in all experimental groups. There were similar (P < 0.05) decreases in MAFbx and TNF-α gene expression in the injured and GaAs-injured groups, compared to control group. The MyoD gene expression increased (P = 0.008) in the GaAs-injured group, but not in the injured group (P = 0.338), compared to control group. GaAs laser therapy had a positive effect on MyoD gene expression, but not IGF-I, MAFbx, and TNF-α, during intermediary phases (14 days post-injury) of muscle repair.

AVALIAÇÃO DO FOTOPERÍODO E DURAÇÃO DO PROTOCOLO COM PROGESTÁGENO SOBRE A CONCENTRAÇÃO PLASMÁTICA DE PROGESTERONA EM OVELHAS INSEMINADAS EM TEMPO FIXO

Os objetivos do presente trabalho foram: avaliar, na primavera e verão (novembro a março), a concentração plasmática de progesterona em ovelhas lanadas e deslanadas criadas no oeste paulista; avaliar a concentração plasmática de progesterona em função do tempo de permanência do progestágeno (6, 9 ou 12 dias) em protocolo de inseminação artificial em tempo fixo (IATF). No experimento 1 foram utilizadas 12 ovelhas mestiças: 6 padrão Texel (Te) e 6 Santa Inês (SI), nas quais foram feitas, entre novembro e março, sete colheitas de sangue (C1 a C7), por venopunção da jugular, para posterior dosagem de progesterona (P4)por radioimunoensaio (RIA). No experimento 2 foram utilizadas 38 ovelhas Te e SI divididas aleatoriamente em três grupos: G-6 (n= 13); G-9 (n= 13); e G-12 (n= 12). Inicialmente cada ovelha recebeu uma esponja intravaginal de progestágeno (D0) que permaneceu por 6 (G-6), 9 (G-9) ou 12 dias (G-12). Na retirada da esponja foram administrados, por via intramuscular, 0,1315 mg de prostaglandina F2α (PGF2α) e 300 UI de gonadotrofina coriônica equina (eCG). A IATF, por via laparoscópica, foi feita a partir de 50 horas após a retirada do progestágeno. Trinta dias após foi realizado diagnóstico de gestação através de ultrassonografia transabdominal. Exp. 1. Com exceção da colheita 7 (C7), em todas as outras o grupo SI apresentou concentração de P4 estatisticamente superior (P<0,05) ao grupo Te. Exp. 2. No momento da retirada do progestágeno o G-12 apresentou concentração de P4 significativamente (P<0,05)menor (0,342 ng/mL) que o G-6 (1,684 ng/mL) e G-9 (1,762 ng/mL). No entanto não houve diferença na taxa de prenhez entre os grupos G-6 (76,9%), G-9 (61,5%) e G-12 (91,6%). As ovelhas SI apresentaram concentração plasmática de P4 maior que as ovelhas Te nos períodos avaliados. A duração da permanência do progestágeno não afeta a taxa de prenhez em ovelhas.

Different extenders in the cryopreservation of bovine epididymal spermatozoa

The objective of this study was to evaluate the effects of two different egg yolk extenders incubated with or without Sperm Talp on the motility and plasma membrane integrity of cryopreserved bovine epididymal spermatozoa after freezing. Twenty-five testicles with epididymides from mature bulls were collected at the abattoir. Epididymal sperm recovery was performed by retrograde flushing using a skim milk-extender (Botu-Semen™). After recovery, sperm were incubated either without or with Sperm Talp and then submitted to centrifugation. For the freezing process, half of the testes were processed with Tris egg yolk extender, and half were processed with Botu-Bov™ egg yolk extender. Samples incubated in Sperm Talp exhibited better results than epididymal spermatozoa that were incubated without Sperm Talp (p<0.05). Both Botu-Bov™ and Tris could be utilised to freeze sperm from the bovine epididymides if the sperm were previously incubated with Sperm Talp. The extenders examined in this work did not differ in their effect on plasma membrane integrity after freezing.

Expression and function of fibroblast growth factor 10 and its receptor, fibroblast growth factor receptor 2B, in bovine follicles

Some fibroblast growth factors (FGFs) affect ovarian follicle cell growth and/or differentiation. Whereas many FGFs activate several FGF receptors, FGF7 and FGF10 primarily activate only one, FGFR2B. As FGF7 is produced by bovine theca cells and acts on granulosa cells, we tested the hypothesis that FGF10 may also play a role in folliculogenesis in cattle. Reverse transcription-polymerase chain reaction demonstrated the presence of FGF10 mRNA in the oocytes and theca cells of the antral follicles, as well as in the preantral follicles. FGF10 protein was detected by immunohistochemistry in the oocytes of the preantral and antral follicles, and in the granulosa and theca cells of the antral follicles. FGF10 expression in theca cells changed during follicle development; mRNA abundance decreased with increasing follicular estradiol concentration in healthy follicles, and was lowest in highly atretic follicles. Culturing of granulosa cells in serum-free medium revealed FSH regulation of FGF10 receptor expression. The addition of FGF10 to cultured granulosa cells decreased the level of estradiol but did not alter cell proliferation. These data support a role for FGF10 in signaling to granulosa cells from theca cells and/or the oocyte.

Expression of fibroblast growth factor-8 and regulation of cognate receptors, fibroblast growth factor receptor-3c and -4, in bovine antral follicles

Paracrine cell signaling is believed to be important for ovarian follicle development, and a role for some members of the fibroblast growth factor (FGF) family has been suggested. In the present study, we tested the hypothesis that FGF-8 and its cognate receptors (FGFR3c and FGFR4) are expressed in bovine antral follicles. RT-PCR was used to analyze bovine Fgf8, Fgfr3c and Fgfr4 mRNA levels in oocytes, and granulosa and theca cells. Fgf8 expression was detected in oocytes and in granulosa and theca cells; this expression pattern differs from that reported in rodents. Granulosa and theca cells, but not oocytes, expressed Fgfr3c, and expression in granulosa cells increased significantly with follicle estradiol content, a major indicator of follicle health. Fgfr4 expression was restricted to theca cells in the follicle, and decreased significantly with increasing follicle size. To investigate the potential regulation of Fgfr3c expression in the bovine granulosa, cells were cultured in serum-free medium with FSH or IGF-I; gene expression was upregulated by FSH but not by IGF-I. The FSH-responsive and developmentally regulated patterns of Fgfr3c mRNA expression suggest that this receptor is a potential mediator of paracrine signaling to granulosa cells during antral follicle growth in cattle.

Expression of fibroblast growth factor-8 and its cognate receptors, fibroblast growth factor receptor (FGFR)-3c and-4, in fetal bovine preantral follicles

Paracrine cell signaling is thought to be important for ovarian follicle development, and a role for some members of the fibroblast growth factor (FGF) family have been suggested. In the present study, we tested the hypothesis that FGF-8 and its cognate receptors (FGFR-3c and FGFR-4) are expressed in bovine preantral follicles. Reverse transcription-polymerase chain reaction was used to amplify bovine FGF-8, FGFR-3c, and FGFR-4 from preantral follicle samples and a variety of fetal and adult tissues. All three genes were widely expressed in fetal tissues, with a restricted expression pattern in adult tissues. FGF-8 and FGFR-3c were expressed in secondary follicles in 70% of fetuses examined, whereas FGFR-4 expression was significantly less frequent (20%). FGFR-3c expression frequency was significantly lower in primordial compared to secondary follicles, and FGF-8 expression showed a similar trend. FGFR-4 was only observed when all follicle classes of an individual were expressing both FGF-8 and FGFR-3c. We conclude that FGF-8 and its receptors are expressed in preantral follicles in a developmentally regulated manner.

Angiotensin II reverses the inhibitory action produced by theca cells on bovine oocyte nuclear maturation

The presence of prorenin, renin, angiotensinogen, angiotensin-converting enzyme, angiotensin II (Ang II) and Ang II receptors in the ovary is suggestive of a functional ovarian renin-angiotensin system (RAS). In cattle, the expression of Ang II is greatest in large follicles, suggesting that it is important during follicular growth and maturation. The present study was designed to investigate the role of Ang II in bovine oocyte nuclear maturation. Bovine cumulus-oocyte complexes (COCs) were cultured with or without follicular cells and Ang II or saralasin (Ang II antagonist). In the absence of follicular cells, Ang II at 0, 10(-11), 10(-9) and 10(-7) M did not affect the percentage of oocytes reaching the germinal vesicle breakdown (GVBD), metaphase I (MI) and metaphase II (MII) stage after 7-h (41.3 +/- 4.3, 35.3 +/- 4.0, 31.3 +/- 9.7, 38.7 +/- 8.6), 12-h (31.6 +/- 7.0, 34.7 +/- 6.1, 31.7 +/- 5.3, 28.9 +/- 9.1; mean +/- S.E.M.) and 18-h (44.9 +/- 7.3, 58.4 +/- 8.4, 53.1 +/- 7.4, 44.9 +/- 7.3) of culture, respectively. Similarly, saralasin at 0, 10(-11), 10(-9) and 10(-7) M did not affect the percentage of oocytes reaching MII stage after 18-h of culture (37.6 +/- 7.4, 34.4 +/- 7.7, 30.0 +/- 10.8 and 31.2 +/- 5.1, respectively). The theca cells (MII = 22.9%) or medium conditioned with follicular cells (GV = 65.5%, MI = 23.6%) inhibited oocyte maturation; however, theca cells (MII = 35.5 +/- 4.9; P < 0.05) or medium conditioned with follicular cells (GV = 34.6%, MI = 52.7%; P < 0.01) were not able to inhibit nuclear maturation when Ang II (10(-11) M) was present in the culture system. Theca cells remained viable during the culture period when Ang II was present. Therefore, results supported the idea of a role of Ang II in blocking the inhibitory effect of theca cells on nuclear maturation of bovine oocytes.