Intrauterine infusion of killed semen adversely affects uterine blood flow and endometrial gene expression of inflammatory cytokines in mares susceptible to persistent breeding-induced endometritis.

Persistent breeding-induced endometritis (PBIE) is a leading cause of infertility in mares. The objective of the study was to assess genital perfusion and endometrial gene expression of inflammatory cytokines in mares classified as susceptible (n = 5) or resistant (n = 5) to PBIE. Ten mares were examined daily during estrus until 6 d after hCG-induced ovulation for two estrous cycles. Twenty-four hours after application of 1500 IU hCG, 4 mL of killed (by repeated freezing in liquid nitrogen and thawing at 50 °C) deep-frozen semen or sterile saline was instilled into the uterine body and examinations were carried out immediately before and 3, 6, and 12 h after intrauterine infusion. Examinations included blood sampling to determine plasma progesterone (P4) concentrations, and transrectal ultrasonography in B- and color Doppler mode to determine follicular and luteal size and blood flow, the extent of intrauterine fluid, as well as time-averaged maximum velocity (TAMV), blood flow volume (BFV), and blood flow resistance (expressed as pulsatility index, PI) of the uterine arteries. Additionally, endometrial biopsies were obtained at 24 h before, and 2 and 7 d after infusion, and mRNA expressions of IL1B, IL6, IL8, IL10, TNF, CASP3, and COX2 were determined by qRT-PCR. Statistical analyses were performed with mixed models. Intrauterine fluid retention (diameter >20 mm for at least 3 d) was found after infusion of killed semen in five susceptible mares. There was no treatment effect (semen vs saline; P > 0.05) on genital blood flow, plasma P4 concentration, and endometrial gene expression. In comparison to resistant mares, susceptible mares had an increased (P = 0.04) BFV of the uterine arteries at 24 h before intrauterine infusion of killed semen, and an increased (P = 0.03) PI at 2 d after infusion. The TAMV, plasma P4 concentrations, and follicular and luteal size and blood flow did not differ (P > 0.05) between resistant and susceptible mares. Endometrial mRNA expression of IL1B increased (P = 0.05) at 2 d after the infusion of killed semen in the susceptible mares, and the expression of IL10 increased (P = 0.003) at 7 d after the infusion within the resistant mares. Interleukin 6 mRNA was increased (P = 0.05) in susceptible compared to resistant mares at 2 d after infusion. In summary, an intrauterine infusion of killed semen increases uterine blood flow resistance and alters endometrial gene expression of inflammatory cytokines for at least 7 d but does not affect ovarian blood supply and luteal function in mares susceptible to PBIE.

Gene expression of matrix metalloproteinases and LH receptors in mare follicular development.

The period from the emergence of a dominant follicle until its formation requires tissue remodeling. Enzymes promoting collagen lysis, such as matrix metalloproteinases (MMPs), are fundamental for the process of extracellular matrix remodeling, which allows changes in ovarian tissue architecture during follicular growth. It has been suggested that the production of these enzymes may be affected by the rise in circulating concentrations of LH, which acts on the ovarian surface epithelium (OSE). The aim of this study was to determine the expression of MMP-1, MMP-2, and LH receptor (LHR) in the ovulation fossa and in the central portion of the equine ovary during follicular deviation and dominance. Ovaries of 12 cyclic mares were selected and subsequently divided into two groups: development (DEV) group and dominant (DOM) group. The DEV group consisted of ovaries from six animals whose follicles were less than 28 mm in diameter (follicular deviation), and the DOM group consisted of ovaries from six animals whose follicles measured 28 mm or more in diameter (dominant follicles). The latter group was divided into two subgroups: the group of ovaries with a dominant follicle (DOM-D) and the group of contralateral ovaries (DOM-C). Our results showed that mRNA for MMP-1, MMP-2, and LHR was present in the equine ovary during follicle development, in the ovulation fossa, and in the central portion of the ovary. MMP-1 and LHR gene expression was greater (P < 0.05) for the DOM-D group compared with the DOM-C group. In the DOM-D group, MMP-1, MMP-2, and LHR gene expression was greater (P < 0.05) in the ovarian stroma compared with the ovulation fossa. Using immunohistochemistry, OSE from the DOM group showed increased expression compared with the DEV group (P < 0.05). In conclusion, we demonstrated that MMP-1 and MMP-2 might be fundamental for events related to tissue remodeling, which occurs during follicular development until the formation of the dominant follicle. We also demonstrated the relationship between the gene expression of MMPs and the gene and protein expression of LHR, suggesting that LHR in the OSE might be an important factor to initiate the signaling cascade that culminates with the production of MMPs.

Effects of aerobic conditioning on salivary IgA and plasma IgA, IgG and IgM in older men and women.

As people age, they experience a decline in immune responses. Unusually heavy acute or chronic exercise could increase the risk of upper respiratory tract infection (URTI) whereas regular moderate physical activity may reduce URTI symptomatology. The purpose of the present study was to determine whether an aerobic exercise program would promote chronic adaptations in plasma IgA, IgG and IgM, and salivary IgA (Sal-IgA) in both elderly women and men. Forty-three independently living men and women, aged between 65 and 96 years, were randomly assigned to an aerobic exercising or a control group. Each participant underwent three evaluations (pre, post at 16 weeks and follow-up at 32 weeks). The aerobic exercise group increased resting plasma IgA concentration from 1.08 g. L (-1)+/-0.50 g. L (-1) to 2.29 g. L (-1)+/-0.93 g. L (-1), whereas salivary IgA concentration was unchanged. The control group maintained the plasma IgA values but experienced a decrease in Sal-IgA. The IgG and IgM plasma concentrations increased in both groups, however, only the exercise group maintained higher values in the final follow-up evaluation. Regular aerobic exercise may be effective in promoting IgA immunity and protecting against the deterioration in Sal-IgA values observed in the control group. No gender differences in the immunoglobulin responses to aerobic training were observed.

Miniature ponies: 1. Follicular, luteal and endometrial dynamics during the oestrous cycle.

Follicular dynamics were studied during 12 interovulatory intervals (IOIs) and 36 preovulatory periods in Miniature mares. The percentage of IOIs with the following follicle events was: ovulatory wave with only one follicle>or=10 mm (55%), diameter deviation similar to previous reports in larger mares (25%) and minor waves emerging before or after the ovulatory wave (55%). Follicle data were compared among Miniature ponies, large ponies and Breton horses (n=12 IOIs per breed). The IOI was longer (P<0.001) in Miniature ponies (23.3+/-0.9 days) and in large ponies (23.9+/-0.5 days) than in Breton horses (20.3+/-0.7 days). The Miniature ponies had fewer (P<0.0001) growing follicles>or=10 mm per ovulatory wave (1.5+/-0.3) and more (P<0.0004) ovulatory waves (6/11) with only one follicle>or=10 mm than large ponies (9.8+/-0.8 and 0/12) and horses (5.8+/-0.9 and 0/12). Maximum diameter of the preovulatory follicle was smaller (P<0.003) in the Miniature ponies (38.3+/-0.7 mm) than in the horses (44.5+/-1.4 mm), but the difference between breeds was slight (6%) compared with the difference in bodyweight (65%). Considering the small number of follicles per ovulatory wave, Miniature mares are a potential model for comparative studies in folliculogenesis within and among species.

Miniature ponies: 2. Endocrinology of the oestrous cycle.

Plasma concentrations of FSH, LH, oestradiol and progesterone were studied daily during 12 interovulatory intervals and 21 periovulatory periods in nine Miniature ponies. The peak of the FSH surge that was temporally associated with emergence of the future ovulatory follicle occurred when the follicle was approximately 9 mm, compared with a reported diameter of 13 mm in larger breeds. The ovulatory LH surge involved a slow increase between Days 13 and 18 (ovulation=Day 0; 0.6+/-0.1 ng day(-1)), a minimal increase or a plateau on Days 18 to 21 (0.04+/-0.1 ng day(-1)), and a rapid increase after Day 21 (2.2+/-0.4 ng day(-1); P<0.0001). The end of the plateau and the beginning of the rapid increase occurred on the day of maximum concentration in the oestradiol preovulatory surge. An unexpected mean increase and decrease in LH occurred (P<0.04) on Days 5 to 9. Concentrations of oestradiol and progesterone seemed similar to reported results in larger breeds. Results indicated that in Miniature ponies the peak of the FSH surge associated with emergence of the future ovulatory follicle occurred at a smaller diameter of the future ovulatory follicle than in larger breeds, the ovulatory LH surge increased in three phases, and the ovulatory LH surge was followed by an LH increase and decrease during the early luteal phase.