Person: Lorenzo González, Pedro Luis
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First Name
Pedro Luis
Last Name
Lorenzo González
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Veterinaria
Department
Fisiología
Area
Fisiología
Identifiers
12 results
Search Results
Now showing 1 - 10 of 12
- Project number: 76
Item Biotecnologías de la reproducción I: laboratorio virtual de producción de embriones(2015) Arias Álvarez, María; García García, Rosa María; Lorenzo González, Pedro Luis; García Rebollar, Pilar; Revuelta Rueda, Luis; González Gil, Alfredo Item Physiological effects on rabbit sperm and reproductive response to recombinant rabbit beta nerve growth factor administered by intravaginal route in rabbit does(Theriogenology, 2020) Sánchez Rodríguez, Ana; Arias Álvarez, María; Millán Pastor, María Pilar; Lorenzo González, Pedro Luis; García García, Rosa María; García Rebollar, PilarBeta nerve growth factor (β-NGF) is present in the seminal plasma of some species, including rabbits, acting as an ovulation-inducing factor in camelids. Traditionally, GnRH analogues are used to induce ovulation by intramuscular route when artificial insemination (AI) is performed in rabbit does. A specific rabbit recombinant β-NGF (rrβ-NGF) produced in our laboratory was tested as an alternative method to conventional treatment with GnRH analogues to induce ovulation. In the present work, different concentrations (0, 20, 100 ng/mL and 1, 20 and 100 μg/mL) of rrβ-NGF were added to diluted semen to assess its effect on sperm traits (viability and motility parameters). rrβ-NG was used also, incorporated to the AI dose, to evaluate ovulation response (LH and progesterone plasma concentrations, ovulation rate (OR) and embryo implantation at Day 7) after intravaginal administration. A negative control group stimulated with an empty catheter, and a positive control group inseminated and intramuscularly treated as usual with GnRH were also set up. Results showed that seminal quality was influenced by rrβ-NGF depending on the concentration added, being the highest concentrations tested deleterious for semen. Whereas the highest OR was found in the positive control group (100%), concentrations of 20 ng/mL, 1 μg/mL and 20 μg/mL of rrβ-NGF triggered intermediate OR (30, 60 and 42.9%, respectively), and 100 ng/mL and 100 μg/mL had the lowest OR (20 and 14.3%, respectively). Although LH peak was not observed in the first 2 h after AI in the ovulated females from rrβ-NGF groups, plasma progesterone significantly increased at Day 7, except in those females treated with 20 and 100 μg/mL. Also, 98.4% of ovulated females were pregnant on Day 7. In conclusion, rrβ-NGF added to diluted semen affects seminal quality and provokes ovulation, the development of functional CL and conception by intravaginal route in rabbit does, depending on the concentration added.Item Managing sexual receptivity and ovulation induction in rabbit does: evidence from recent research(World Rabbit Science, 2023) García Rebollar, Pilar; Arias Álvarez, María; Lorenzo González, Pedro Luis; García García, Rosa MaríaThe sexual receptivity and ovulation induction of the reproductive rabbit are key points determining their success in productive life. Adequate synchronisation of the sexual receptivity methods of inseminated rabbit does unquestionably favours fertility and prolificacy outcomes. This review aims to bring together the different methods applied in synchronising primiparous rabbits and the consequences at metabolic, endocrine and ovarian levels, as well as in the embryonic, foetal and post-natal development that our research group has studied over the years. Likewise, the latest advances regarding ovulation induction in the rabbit are described, as well as the search for alternatives to the intramuscular injection of synthetic analogues of gonadotropins and seminal plasma components that could be involved in this process. Different experiments performed with a physiological basis confirm that nerve stimulation during artificial insemination or coitus is especially important in the ovulation induction reflex in rabbit females.Item Recombinant rabbit beta nerve growth factor production and its biological effects on sperm and ovulation in rabbits(PLoSONE, 2019) Sánchez Rodríguez, Ana; Abad, Paloma; Arias Álvarez, María; Millán Pastor, María Pilar; García Rebollar, Pilar; Bautista Santa Cruz, José Manuel; Lorenzo González, Pedro Luis; García García, Rosa MaríaIn some induced-ovulating species, beta nerve growth factor (β-NGF) has important roles in ovulation, though data for rabbits are still inconclusive. In this study we first synthesized functional recombinant β-NGF from rabbit tissue (rrβ-NGF) to address the following objectives: 1) to compare rabbit β-NGF amino acid sequence with those of other induced- or spontaneous-ovulating species; 2) to assess the effects of rrβ-NGF on rabbit sperm viability and motility, and 3) to examine the in vivo ovulation inducing effect of rrβ-NGF added to the seminal dose in rabbit does. The NGF gene in rabbit prostate tissue was sequenced by Rapid Amplification of cDNA Ends and annotated in GenBank (KX528686). Recombinant rβ-NGF was produced in CHO cells and purified by affinity chromatography. Once confirmed by Western blotting and mass spectrometry (MALDI-TOF) that the amino acid sequence of the recombinant protein corresponded to β-NGF, its functionality was validated in PC12 cells in a successful dose-response study over 8 days. The amino acid sequence of prostate rabbit NGF differed to that of other species mainly in its receptor binding sites. In all the spontaneous ovulating species examined, compared with rabbit, alanine and proline residues, which interact with the high-affinity receptor, were replaced by a serine. In rabbits, asparagine and methionine were substituted by lysine at the low-affinity receptor binding site. In time- and dose-response experiments, the in vitro addition of rrβ-NGF to the ejaculate did not affect sperm viability whereas sperm motility parameters were enhanced by the addition of 1 μg/mL of the neuropeptide. Addition of this same concentration of rrβ-NGF to the seminal dose administered via the intravaginal route in does induced ovulation with a delayed LH peak, leading to a plasma progesterone increase, gestation and delivery. Our findings suggest that rrβ-NGF could be a useful option for biotechnological and reproduction assisted techniques in rabbits but further studies are needed.Item Reproductive and Nutritional Management on Ovarian Response and Embryo Quality on Rabbit Does(Reproduction in Domestic Animals, 2014) Lorenzo González, Pedro Luis; García García, Rosa María; Arias Álvarez, María; García Rebollar, PilarRabbit does in modern rabbitries are under intensive reproductive rhythms. Females are high milk producers with high energetic expenses due to the extensive overlap between lactation and gestation. This situation leads to a negative energy balance with a mobilization of body fat especially in primiparous rabbit does. Poor body condition and poor health status severely affect the reproductive features (fertility rate and lifespan of the doe as well as ovarian physiology). This paper reviews some reproductive and nutritional approaches used in the last years to improve the reproductive performance of rabbit females, mainly focusing on the influence on ovarian response and embryo quality and with emphasis on epigenetic modifications in pre-implantation embryos and offspring consequences.Item A diet supplemented with n-3 polyunsaturated fatty acids influences the metabolic and endocrine response of rabbit does and their offspring(Journal of Animal Science, 2017) Rodríguez, María; García García, Rosa María; Arias Álvarez, María; Formoso-Rafferty Castilla, Nora; Millán Pastor, María Pilar; López Tello, Jorge; Lorenzo González, Pedro Luis; González Bulnes, Antonio; García Rebollar, PilarThe aim of the present study was to evaluate the productive, endocrine, and metabolic responses as well as oxidative stress of rabbit does and their offspring when fed a diet supplemented with n-3 PUFA during their first productive cycle. To this aim, a total of 105 rabbit does were fed ad libitum from d 60 to 172 of age 2 isoenergetic and isoproteic diets differing in fatty acid composition. The control diet (n = 52 does) contained 45.9 g/kg of n-3 of the total fatty acids and the enriched diet (n = 53 does) contained 149.2 g/kg of n-3 of the total fatty acids. Both experimental groups had similar feed intake during rearing, pregnancy, and lactation. The enrichment of diet had no effect on ultrasonographic assessment of does on d 9 and 16 of pregnancy, with an embryonic vesicle number and fetus and placenta size similar between groups (P > 0.05). Even though there were no major effects (P > 0.05) on fertility, duration of gestation, and number born alive and stillborn kits at parturition, live kits from enriched does were longer (71.6 ± 2.42 vs. 79.5 ± 2.13 mm; P < 0.05) and tended to be heavier (42.5 ± 3.94 vs. 50.8 ± 3.47 g; P = 0.07) than those from control does (P < 0.05). The 2 groups had similar milk production and mortality values during lactation; consequently, there were no differences between diets in ADG, litter weight, and number of weaned kits (P > 0.05). In enriched does, higher plasma leptin and estradiol concentrations than in control does (P < 0.05) were observed. In addition, enriched females also had lower total and high-density lipoprotein cholesterol (HDL-c) than control females during lactation (P < 0.05). Regarding offspring, the enrichment of diet with PUFA caused a hyperlipidemic status (greater values of plasma triglycerides, total cholesterol, and HDL-c; P < 0.05) at 1 d postpartum (dpp), compared with the control group, that disappeared at 32 dpp. Supplemented does before parturition and their offspring at 1 dpp had greater oxidative stress than those in the control group. In conclusion, an increase of n-3 PUFA concentration in the diet of rabbit does and, consequently, of their offspring during a productive cycle alters their lipid profile and the indicators of oxidative stress, without major endocrine modifications or improvements in the productive variables.Item Reproductive long-term effects, endocrine response and fatty acid profile of rabbit does fed diets supplemented with n-3 fatty acids(Animal Reproduction Science, 2014) García Rebollar, Pilar; García García, Rosa María; Arias Álvarez, María; Millán Pastor, María Pilar; Rey Muñoz, Ana Isabel; Rodríguez, M.; Formoso-Rafferty Castilla, Nora; Riva Andrés, Sara de la; Masdeu, María del Mar; Lorenzo González, Pedro Luis; García Rebollar, PilarThe effect of a diet enriched with polyunsaturated n-3 fatty acids (PUFA) on endocrine, reproductive, and productive responses of rabbit females and the litters has been studied. Nulliparous does (n = 125) were fed ad libitum from rearing to second weaning two diets supplemented with different fat sources: 7.5 g/kg lard for the control diet (group C; n = 63) or 15 g/kg of a commercial supplement containing a 50% ether extract and 35% of total fatty acids (FAs) as PUFA n-3 (Group P; n = 62). Dietary treatments did not affect apparent digestibility coefficients of nutrients, or reproductive variables of does including milk production, mortality and average daily gain of kits over two lactations. However, on Day 5 and 7 post-induction of ovulation, progesterone of Group P tended to increase to a greater extent than in does of Group C. Total PUFAs, n-6 and n-3 and eicosapentanoic (EPA) contents were greater in adipose tissues of does in Group P than in Group C. Docosapentaenoic acid (DPA), EPA, and docosahexaenoic acid (DHA) concentrations were greater in peri-ovarian than in scapular fat with abdominal fat being intermediate in concentration. In PUFA supplemented does, kit mortality at the second parturition tended to be less than in control does. Also, kits born to does of the PUFA-supplemented group weighed more and were of greater length than from does of control group. In conclusion, effectiveness of dietary intervention on reproductive and performance response is greater in the second parity, which suggests an accumulative long-term beneficial effect of n-3 FA supplementation in reproductive rabbit does.Item Acute fasting before conception affects metabolic and endocrine status without impacting follicle and oocyte development and embryo gene expression in the rabbit(Reproduction, Fertility and Development, 2011) García García, Rosa María; García Rebollar, Pilar; Arias Álvarez, María; Sakr, Osama G.; Bermejo Álvarez, Pablo; Brecchia, G.; Gutiérrez Adán, Alfonso; Zerani, M.; Boiti, C.; Lorenzo González, Pedro LuisFood deprivation affects female reproduction. The goal of the present study was to elucidate in the rabbit model the effects of acute energy restriction on ovarian function (follicle development, atresia rate and in vitro oocyte maturation) and embryonic development and gene expression of some candidate genes. Serum metabolic parameters (non-esterified fatty acids (NEFA), triglycerides, glucose, insulin and leptin concentrations) and endocrine markers (oestradiol-17β and progesterone concentrations) were also studied. A control group of nulliparous does fed ad libitum and a 72-h fasted group were used. At the end of the nutritional treatment, the ovaries of half of the animals were retrieved while the other animals were re-fed and artificially inseminated to recover embryos at 84 h after insemination, during the luteal phase. At the end of fasting, increased serum NEFA and decreased leptin concentrations were observed in the fasted group, but no differences appeared in serum steroid concentrations, follicle population and atresia rate or nuclear and cytoplasmic oocyte maturation. In the luteal phase, insulin concentrations increased notably in the fasted group. The number of recovered embryos per female and the speed of embryo development were reduced in the food-deprived group. Acute fasting altered both metabolic and endocrine markers and embryo development, but follicle and oocyte development and embryo gene expression were not affected.Item Effects of a lignin-rich fibre diet on productive, reproductive and endocrine parameters in nulliparous rabbit does(Livestock Science, 2009) Arias Álvarez, María; García García, Rosa María; García Rebollar, Pilar; Nicodemus, Nuria; Revuelta Rueda, Luis; Millán Pastor, María Pilar; Lorenzo González, Pedro LuisIn rabbits, modifications in dietary composition may be associated with reproductive benefits. However, the influence of nutrition on ovarian function and embryo development is poorly known in this species. The goal of this work was to study the short-term effects of feeding high-fibre diets with different levels of lignin during the rearing period on productive, endocrine and reproductive parameters of nulliparous rabbit does. A total of 95 New Zealand × California 11-week-old nulliparous white rabbits were randomly allocated in two experimental groups fed ad libitum fibre-rich diets with a high lignin content (HL group: NDF 49.6% of DM, LAD 15.8% of DM; n = 48) or a standard lignin content (SL group: NDF 40.9% of DM, LAD 4.9% of DM; n = 47). All animals were artificially inseminated (AI) at 16 weeks of age. Daily feed intake and live body weight (LBW) were recorded during the rearing period. Conception rate and prolificacy were also determined. In addition, in ten animals of each group, body composition, serum estradiol 17β (E2), progesterone (P4) and leptin levels, as well as reproductive parameters including ovary weight, follicular population, ovulation rate, in vitro oocyte maturation (IVM), blastocyst recovery rate and in vitro embryo development were studied at AI time. Animals fed the HL diet had a significantly higher feed intake until the first AI (P < 0.003) and during the first pregnancy (P < 0.03). At 16 weeks of age, animals fed the HL diet had a lower content of lipids (P < 0.05) and crude energy (P < 0.05) than those fed the SL diet, but average LBW of does, ovary weight, and ovulation rate per doe were similar between HL and SL treatments. No significant differences were found in P4 levels. However, the HL group had elevated E2 serum levels (P < 0.003) compared to those fed with the SL diet, whereas antral follicular population was similar between groups. Both nuclear and cytoplasmic IVM measured as metaphase II and cortical granule migration rates were also similar between both groups. In addition, no differences in blastocyst recovery rate or in prolificacy were found. However, mean serum leptin levels (P < 0.05), in vitro embryo development (P < 0.03), and fertility rate (P < 0.02) were higher in the SL group compared to the HL group. In conclusion, the HL diet enhanced feed intake of does, but reduced serum leptin levels at AI time, in vitro embryo survival and conception rate.Item Characterization of β-Nerve Growth Factor-TrkA system in male reproductive tract of rabbit and the relationship between β-NGF and testosterone levels with seminal quality during sexual maturation(Theriogenology, 2019) Sánchez Rodríguez, Ana; Arias Álvarez, María; Timón, Patricia; Bautista Santa Cruz, José Manuel; García Rebollar, Pilar; Lorenzo González, Pedro Luis; García García, Rosa Maríaβ-Nerve Growth Factor (β-NGF) is a neurotrophin which acts through its receptors TrkA and p75, performing important actions in male reproductive physiology and its presence in seminal plasma (SP) has been related to male fertility. The aim of the present study was to evaluate the gene expression profile and the immunolocalization of β-NGF and its high-affinity receptor TrkA in sex organs in rabbits during sexual maturation period. β-NGF concentration for both SP and blood plasma (BP) and BP testosterone levels were determined as well as the seminal parameters during such period. Ten New Zealand White x California young rabbits were trained to semen collection since 20 weeks of age and routinely done once a week with two ejaculations per session. At 22 and 37 weeks of age, semen collection was carried out three times a week and seminal parameters were evaluated. Four males were randomly assigned and slaughtered in each age (n = 8); sex organs (prostate, bulbourethral glands and epididymis) were dissected and collected to determine β-NGF and TrkA gene expression and immunolocalization. SP and BP were also taken at each semen collection session to evaluate β-NGF concentration, and testosterone levels were also assessed in BP. The highest β-NGF mRNA expression was observed in prostate compared to bulbourethral glands and epididymis. These two last tissues showed residual β-NGF mRNA expression and limited localization of the neurotrophin. The prostate epithelial cells and lumen were strongly stained with regard to the other sex organs indicating that immunolocalization of β-NGF rely mainly in the prostate. TrkA gene expression was lower but constant and differentially immunolocalized in the sex organ tissues. Finally, β-NGF concentration in SP and BP remained unchanged in accordance to age, while some seminal characteristics such as sperm concentration, percentage of live sperm and mass and progressive motility were enhanced as endowed by BP testosterone variation. β-NGF and its cognate TrkA receptor are expressed and immunolocalized in the male reproductive tract in the two ages studied, independently of the circulating levels of testosterone and β-NGF.