Abstract:

Aims To acquire data on the safety-in-use of the probiotic Saccharomyces cerevisiae RC016 and test its ability to reduce genotoxicity caused by dietary aflatoxins (AFs). Methods and Results The probiotic was orally administered to Wistar rats. Six groups (n = 6) were arranged: feed and probiotic controls, two levels of AFs-contaminated feed and two treatments including both the probiotic and the toxin. Genotoxiciy and cytotoxicity were evaluated with the bone marrow micronuclei assay and the comet assay and internal organs were macroscopically and microscopically examined. The tested S. cerevisiae strain did not cause genotoxicity or cytotoxicity in vivo, and it was able to attenuate AFs-caused genotoxicity. Saccharomyces cerevisiae RC016 did not cause any impairment on the rats' health and it showed no negative impact on the weight gain. Moreover, RC016 improved zootechnical parameters in AFs-treated animals. The beneficial effects were likely to be caused by adsorption of AFs to the yeast cell wall in the intestine and the consequent reduction in the toxin's bioavailability. Conclusions The dietary administration of RC016 does not induce genotoxicity or cytotoxicity to rats. Significance and Impact of the Study Incorporation of RC016 in the formulation of feed additives increases animal productivity. Similar effects may even occur in human food applications.

Author affiliation: Gonzalez Pereyra, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Dogi, Cecilia Ana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Torres, Adriana Mabel. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Wittouck, P.. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Ortiz, María del Pilar. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Escobar, Franco Matias. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Bagnis, G. Universidad Nacional de Rio Cuarto. Facultad de Agronomia y Veterinaria. Departamento de Patología Animal; Argentina

Author affiliation: Yaciuk, Raul Ernesto. Universidad Nacional de Rio Cuarto. Facultad de Agronomia y Veterinaria. Departamento de Patología Animal; Argentina

Author affiliation: Poloni, Valeria Lorena. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Torres, Adriana Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Dalcero, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Author affiliation: Cavaglieri, Lilia Reneé. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina

Abstract:

Maternal nutritional restrictions during late gestation could lead to fetal hypoglycemia. Glucose levels in the fetal sheep regulate circulating insulin-like growth factor 1 (IGF1) levels, which stimulate cell proliferation and differentiation of reproductive organs after binding to its own receptor or estrogen receptors. The objective of this study was to determine the effects of subnutrition of ewes during the last trimester of gestation on the serum glucose/IGF1 levels and development of reproductive organs in their lambs. Pregnant ewes carrying singletons were randomly assigned to restricted (R ewes, n = 8) or control (C ewes, n = 8) groups (4 lambs of each gender/group) and fed with 50% or 100% of metabolic energy requirements from ∼100 days of gestation to term (∼147 days), respectively. Blood samples from lambs were taken on the first day after born and once at week for serum glucose and IGF1 determination. Lambs were euthanatized at 2 months of age, reproductive organs were weighted and tissue samples were collected from them for histology and to measure mRNA expression of IGF1 and its receptor (IGF1R) by qRT-PCR. Pre-partum glucose levels in R ewes were significantly lower compared to C ewes (p <.05). Compared to lambs born from C ewes, lambs born from R ewes showed lower serum levels of glucose and IGF1 during the first week of age (p <.05). At 2 month of age, these lambs had significant lower uterine and testicular weight and lower ovarian, uterine and testicular mRNA expressions of IGF1 and its receptor (p <.05). Histological findings showed that diameter of secondary and tertiary follicles in ovaries and number of endometrial glands in uterus of females, or number of Sertoli cells and seminiferous tubules and diameter, perimeter and tubular area in testicles of males were significantly lower in lambs born from R ewes compared to the respective organs of lambs born from the C ewes (p <.05). In conclusion, these results demonstrate that maternal subnutrition during late gestation affects IGF1 levels during fetal life and impairs reproductive development in the neonatal lamb, which could have permanent negative consequences in the future reproductive performance of the offspring.

Author affiliation: Hoffmann, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina

Author affiliation: Boretto, E.. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina

Author affiliation: Vitale, S.. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina

Author affiliation: Gonzalez, V.. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina

Author affiliation: Vidal, G.. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina

Author affiliation: Pardo, Marcelo Fabián. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina

Author affiliation: Flores, M. F.. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina

Author affiliation: Garcia, F.. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina

Author affiliation: Bagnis, G.. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; Argentina

Author affiliation: Queiroz, O.C.M.. Chr-hansen; Argentina

Author affiliation: Rabaglino, Maria Belen. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Patología Animal; Argentina. Provincia de Córdoba. Ministerio de Ciencia y Técnica. Centro de Excelencia en Productos y Procesos de Córdoba; Argentina