Lactoferrin affects in vitro and in vivo fertilization and implantation in rats.

Lactoferrin (LF) is present in the oviduct, reduces in vitro gamete interaction, and affects sperm capacitation parameters in humans. Our aim was to investigate LF actions on further stages of the reproductive process in the Wistar rat model. Motile sperm were obtained from cauda epididymis to assess LF binding by direct immunofluorescence and LF effect on acrosome reaction (AR) using a Coomassie blue staining. After ovarian hyperstimulation of female rats, oocytes were surgically recovered and coincubated with motile sperm and different doses of LF to estimate the in vitro fertilization (IVF) rate. To evaluate the LF effect on pregnancy and embryo implantation, female rats (80 days old) were placed with males and received daily intraperitoneal injections of LF during one complete estrous cycle (pregnancy experiments) or during the first 8 gestational days (implantation experiments). The number of pregnant females and live born pups was recorded after labor. Moreover, the number of implantation sites was registered during the implantation period. LF was able to bind to the sperm head, midpiece, and tail. 10 and 100 µg/ml LF stimulated the AR but reduced the IVF rate. The administration of 100 and 200 mg/kg LF significantly decreased the number of implantation sites and the litter size, whereas 100 mg/kg LF declined the pregnancy rate. The results suggest that LF might interfere with the reproductive process, possibly interfering with gamete interaction or inducing a premature AR; nevertheless, the mechanisms involved are yet to be elucidated.

Lactoferrin levels in cervical fluid from in vitro fertilization (IVF) patients - correlation with IVF parameters.

Since our previous results suggest that lactoferrin (LF) might have roles in the reproductive process and that its levels might change in the female tract as a response to various factors, the aim of this investigation was to assess whether LF levels in cervical secretions correlate with reproductive parameters from in vitro fertilization (IVF) patients. Cervical fluid samples were obtained from 34 women under 40 years old enrolled for assisted reproduction techniques, and LF concentration was measured. The mean total protein concentration in all cervical fluid samples was 842.8 ± 116.9 µg/mL. The mean concentration of LF was 0.73 ± 0.06 ng LF/µg of total proteins. We observed that higher LF levels in cervical fluid correlated with lower IVF rates when all patients were analyzed; this negative correlation was also sustained when only patients ≥35 years were studied. The mean LF concentration in cervical fluid was significantly lower among patients with normal IVF rates than in those with values 50% or less. Using a LF cutoff value of 0.83 ng/µg of total proteins, the study revealed a significant association between the LF levels below 0.83 ng/µg of total proteins and IVF rates above 50%. LF levels in cervical mucus could potentially be used as a marker of fertilization outcome.

Detección de lactoferrina en secreciones del tracto reproductivo inferior femenino / Detection of lactoferrin in female lower reproductive tract secretions

INTRODUCCIÓN La lactoferrina (LF) está presente en el tracto reproductivo y afectaría la función y la interacción entre gametas. Su expresión sería hormono-dependiente y aumentaría en procesos inflamatorios (una de las principales causas de falla del embarazo e infertilidad). Los tratamientos reproductivos de alta complejidad aún tienen una alta tasa de fracasos, sin motivos aparentes. OBJETIVO Determinar la concentración de LF en el flujo cervical de pacientes de reproducción asistida de alta complejidad y correlacionarla con el resultado de dicho tratamiento. MÉTODOS Se obtuvieron muestras de flujo cervical de pacientes previo a la transferencia embrionaria y de ovodonantes (OV, n=7). Las pacientes se dividieron en las que lograron el embarazo (E, n=16) y las que no lo hicieron (NE, n=21). Se determinó la concentración de proteínas totales y de LF (mediante un ELISA) en el flujo. Los resultados del tratamiento reproductivo se obtuvieron de las historias clínicas. La comparación entre grupos se realizó mediante el test t de Student. RESULTADOS El número de ovocitos recuperados en las E y NE fue similar (7,40 ± 1,17 y 6,33 ± 1,23, respectivamente) pero fueron menores que en las OV (15,14 ± 1,72, p<0,001). Las proteínas totales en flujo fueron más elevadas en las E (1270 ± 286,1µg/ml) con respecto a NE (658,6 ± 117,3 µg/ml, p<0,05). La concentración de LF fue más elevada en NE que en E (1,58 ± 0,56 ng/µg prot. vs. 1,08 ± 0,32 ng/µg prot., respectivamente), pero esta diferencia no fue significativa. DISCUSIÓN El mayor nivel de proteínas en el flujo de las E con respecto a las NE podría sugerir diferencias en la capacidad de secreción del epitelio cervical. La concentración de LF en el flujo fue levemente más baja en E con respecto a NE, pero la diferencia no fue significativa. El tamaño muestral pequeño podría incidir en el resultado encontrado, por lo que se continúa recolectando nuevas muestras de flujo cervical para alcanzar un mayor número de pacientes

Effects of 2,4-dichlorophenoxyacetic acid on the ventral prostate of rats during the peri-pubertal, pubertal and adult stage.

The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is used on a wide variety of terrestrial and aquatic broadleaf weeds. 2,4-D has been shown to produce a wide range of adverse effects on animal and human health. The aim of the current study was to evaluate the effects of pre- and postnatal exposure to 2,4-D on rat ventral prostate (VP). Pregnant rats were exposed daily to oral doses of 70 mg/kg/day of 2,4-D from 16 days of gestation up to 23 days after delivery. Then, the treated groups (n = 8) were fed with a 2,4-D added diet until sacrificed by decapitation on postnatal day (PND) 45, 60, or 90. Morphometric studies were performed and androgen receptor (AR) protein levels in the VP were determined. AR, insulin-like growth factor-I (IGF-1) and insulin-like growth factor-I receptor (IGF-1R) mRNA expression in the VP along with testosterone (T), dihydroxytestosterone (DHT), growth hormone (GH) and IGF-1 serum levels were also determined to ascertain whether these parameters were differentially affected. Results of this study showed that 2,4-D exposure during gestation and until adulthood altered development of the prostate gland in male rats, delaying it at early ages while increasing its size in adults, indicate that 2,4-D could behave as endocrine disruptors (EDs).