Levels of selected cytokines and acute-phase proteins in the serum of dairy cows with cystic ovarian disease and those in follicular and luteal phases of normal ovarian cycle.

The aim of the study was to evaluate the concentration of selected cytokines (tumor necrosis factor [TNFα], interleukin [IL]-6, IL-10) and acute-phase proteins (APPs; haptoglobin [Hp] and serum amyloid A [SAA]) in the serum of cows with follicular and luteal ovarian cysts and in those in the follicular and luteal phases of a physiological ovarian cycle. The study was conducted on 24 Holstein-Friesian (HF) cows: eight cows in the follicular phase of the cycle; the same cows after 10 days when they were in the luteal phase; eight cows with follicular cysts; and eight cows with luteal cysts. Levels of progesterone, 17ß-estradiol, TNF-α, IL-6, IL-10, SAA, and Hp were evaluated in the serum of all examined cows. The concentration of the assessed parameters in the serum was determined using commercially available bovine ELISA kits that were specific for each parameter. The results obtained then showed that values of TNF-α and IL-6 were highest in cows with luteal cysts (p < .001), compared to those with other ovarian structures. The highest level of IL-10 was recorded in cows with two types of ovarian cysts. Furthermore, high values of SAA and Hp were found in cows with two types of cysts; however, these values were higher in cows with follicular cysts. The present study shows that an assessment of the levels of cytokines (pro- and anti-inflammatory) and APPs in the serum may be important in the investigation of the processes underlying the formation and differentiation of ovarian cysts in dairy cows.

Kisspeptin and bovine follicular cysts.

The aim of this study was to investigate kisspeptin (Kp) and sexual hormone blood concentrations in healthy dairy cows (H) and in cows diagnosed with ovarian follicular cysts (FC). Forty dairy cows were enrolled in this study and divided in 2 groups of 20 subjects each. All cows underwent blood collection on the day of diagnosis and on that of heat detection, respectively. Kisspeptin 10, estradiol, and progesterone blood concentrations were assessed. All the parameters were higher in Group FC than in Group H. These results suggest that the higher steroid levels found may have determined the increase in Kp secretion in the cystic cows. This, in turn, may have directly or indirectly stimulated the sustained Luteinizing Hormone (LH) release, known to occur in dairy cystic disease.

A giant ovarian cyst in a neonate with classical 21-hydroxylase deficiency with very high testosterone levels demonstrating a high-dose hook effect.

Congenital adrenal hyperplasia (CAH) is a group of disorders affecting the adrenal steroid synthesis. The most common form, 21-hydroxylase deficiency (21-OHD), leads to decreased production of cortisol and aldosterone with increased androgen secretion. In classic CAH, glucocorticoid treatment can be life-saving and serves to bring the symptoms under control. However, the treatment challenge is to effectively control the excess androgen effect by using the lowest possible glucocorticoid dose. Previous studies suggested a relationship between ovarian cyst formation and adrenal androgen excess, but neonatal large ovarian cysts have been very rarely reported in newborns with CAH. Here, we present the unique case of a neonate with classical 21-OHD who underwent surgery for a giant (10x8x7 cm) unilateral solitary ovarian follicular cyst on the 2nd postnatal day. Hormonal evaluation of the patient revealed high-dose hook effect for serum testosterone levels for the first time by a two-site immunoradiometric assay. Possible mechanisms by which androgen excess may cause ovarian cyst formation are discussed.

Renin and ovarian vascularization in cows with follicular cysts after epidural administration of a GnRH analogue.

The ovarian renin-angiotensin system may play an important role in follicular growth and maturation, as well as in the process of ovulation. The aim of this study was to investigate the effects of administration of a GnRH analogue to cows with ovarian follicular cysts on plasma renin concentrations and ovarian vascularization. This study was performed with 60 Friesian cows, which were diagnosed with follicular cysts, and randomly allocated into two groups: group A (treatment; n=30) received 2ml of lecirelin (Dalmarelin((R)) - Fatro), per head via sacro-coccygeal epidural, and group B (control; n=30) received 2ml saline solution (0.9% NaCl) per head by the same route. Blood samples were immediately collected prior to administration (T0) and then 24h (T1), 48h (T2) and 8 days (T3) after administration of the treatment, for both groups. Ovarian vascularization was evaluated utilizing Power Doppler on these same days in 10 animals from each group. The number of pixels detected by Power Doppler was used as an indicator of the degree of vascularization. Plasma renin concentrations remained relatively constant for the control (group B) animals, but increased as the sampling period progressed (NS) for the treated cows (group A). Similarly, there were no changes in ovarian vascularization (number of pixels) for the control cows, but vascularization increased throughout the sampling period in the treated animals. The number of pixels associated with cysts was significantly higher for treated compared to control cows at 24h after treatment (P<0.001). The epidural administration of a GnRH analogue was determined to be a highly effective therapy for follicular cysts (regression occurred in 82% of treated cows within 8+/-2 days after treatment, but in none of the control cows), which also enhanced ovarian vascularization.

Follicular cysts occur after a normal estradiol-induced GnRH/LH surge if the corpus hemorrhagicum is removed.

The pathophysiology underlying follicular cysts appears to be lack of an estradiol (E2)-induced GnRH/LH surge due to hypothalamic insensitivity to E2. In addition, progesterone (P4) can cause animals with follicular cysts to resume normal cyclicity and normal hypothalamic responsiveness to E2. We postulated that follicular cysts may be a pathological manifestation of a physiological state that cows, and possibly other species, go through during the normal estrous cycle but the rise in P4 following ovulation induces them back to normal hypothalamic responsiveness to E2. Based on this hypothesis, we expected that removal of the ovary containing the corpus hemorrhagicum would prevent the normal rise in P4 following ovulation and induce development of follicular cysts. Cows (n = 24) on day 7 of the estrous cycle were treated with prostaglandin F2alpha (PGF2alpha) and time of ovulation was detected by ovarian ultrasonography every 8 h. Immediately following detection of ovulation, cows were randomly but unequally assigned to have the ovary containing the corpus hemorrhagicum removed (TRT; n = 16) or the ovary opposite to the corpus hemorrhagicum removed (CON; n = 8). Cows were subsequently evaluated by daily ultrasound and blood sampling to determine follicular dynamics. Ovulation was detected at 93.7 +/- 4.5 h after PGF2alpha injection. All CON cows had a normal estrous cycle length (22.0 +/- 0.6 days) after ovariectomy (OVX). Half of the TRT cows became anovular (TRT-ANO; n = 8) after OVX with large anovular follicles developing on the ovary (maximal size, 25.4 +/- 1.4 mm; range, 20-32 mm). However, eight TRT cows ovulated (TRT-OV; n = 8) 7.3 +/- 0.6 days after OVX. Control cows had a normal P4 rise after ovulation. Removal of the newly formed corpus hemorrhagicum prevented the rise in circulating serum P4 in TRT-ANO cows throughout the 25-day experimental period. The TRT-OV cows had a delayed increase in circulating P4 but it was normal in relation to time of ovulation. Serum E2 concentrations were similar among groups (TRT-OV, TRT-ANO and CON cows) until 7 days after OVX. Serum E2 concentrations then decreased in TRT-OV and CON cows but remained elevated (>5 pg/ml) in TRT-ANO cows. Thus, the endogenous increase in circulating E2 that induces the GnRH/LH surge and estrus is sufficient to induce cows into a physiological state that resembles follicular cysts if it is not followed by increased circulating P4.

Changes in interleukin-6 concentration in peripheral blood of pre- and post-partum dairy cattle and its relationship to postpartum reproductive diseases.

Reproductive diseases after parturition are a serious problem in dairy cattle. It is important to predict postpartum reproductive diseases early and to develop prophylaxis. The objectives of this study were to demonstrate changes in the peripheral blood concentration of interleukin-6 (IL-6) before parturition, which was mainly produced by T helper 2 type (Th2) cells, and to investigate a correlation between the IL-6 concentration and the occurrence of the postpartum retained placenta, endometritis and/or follicular cyst in dairy cattle. Twenty-seven Holstein-Friesian cows were used for this study. Thirteen had no clinical disease, 8 had retained placenta, 4 were diagnosed with endometritis by vaginal inspection, and 2 were diagnosed with follicular cyst by rectal palpation at 1 and 2 months after parturition. Blood samples were collected 60 days pre- and post-partum. They used for IL-6, progesterone (P(4)) and estradiol-17beta (E(2)) concentration determination. This study showed that the IL-6 concentration prepartum was higher than postpartum. Low levels of IL-6 and P(4) in peripheral blood prepartum tended to affect retained placenta and a high level of IL-6 prepartum tended to affect endometritis. These results indicate that measurement of change in the IL-6 concentration during pregnancy is one useful tool for predicting crisis in postpartum reproductive diseases in dairy cattle.

Plasma concentrations of inhibin A in cattle with follicular cysts: relationships with turnover of follicular waves and plasma levels of gonadotropins and steroid hormones.

We investigated the profiles of circulating levels of inhibin A and total inhibin in beef cows with follicular cysts in relation to the patterns of follicular development and circulating gonadotropins and steroid hormones. Turnover of follicular waves was monitored in five cows every 2 days for 70 days from 10 days after detection of estrus without ovulation. The mean interwave intervals were 19.6 +/- 1.0 days (n = 18 waves with cysts from the five cows). Circulating levels of inhibin A were approximately 170 pg/ml before emergence of follicular waves with cysts and increased (P < 0.05) concomitantly with follicle emergence. High concentrations of inhibin A (greater than 300 pg/ml) were noted for 7 days during the growth phase of cystic follicles, but inhibin A levels decreased gradually when development of the cysts reached a plateau. This profile of inhibin A was similar to those of total inhibin and estradiol, but was inversely related to the changes in plasma FSH concentrations. LH pulse frequency and mean concentrations of LH in cows with cysts were higher than those observed in the luteal phase of normal cyclic cows. These results indicate that the capacity to secrete inhibin, as well as estradiol, is maintained in cystic follicles, the growth of which is extended by LH secretion at levels greater than those seen in the normal luteal phase. Inhibin A plays an important role in the extension of interwave intervals by suppressing recruitment of a new cohort of follicles.

Relationship among insulin-like growth factor-I, blood metabolites and postpartum ovarian function in dairy cows.

The relationship among nutritional status, systemic insulin-like growth factor-I (IGF-I) and ovarian function early postpartum were investigated. A total of 27 Holstein-Friesian cows, 10 that cycled normally within 20 days postpartum, 5 diagnosed with follicular cysts, 8 with persistent corpus luteum (CL) after the first ovulation postpartum and 4 with inactive ovaries were used for the study. Blood samples were collected 1-3 times per week, for 60 days pre- and postpartum, for IGF-I, progesterone, estradiol, free fatty acids (FFA), blood urea nitrogen (BUN), and aspartate aminotransferase (AST) determination. Inactive ovary and cystic cows had a higher body condition score before calving and lost more condition than normal or persistent CL cows. Immediately postpartum, IGF-I levels were higher and rose sharply in cows that cycled normally than in cystic, inactive ovary or persistent CL cows. At calving and early postpartum, FFA was higher in inactive ovary and cystic than in normal and persistent CL cows. There was a significant strong positive relationship between IGF-I and BUN, and strong negative relationships between IGF-I and FFA and AST in all groups. There was a positive relationship between serum IGF-I and estradiol in normal cystic and inactive ovary cows. This study found that overconditioned cows during the dry period or at calving, lost more body condition postpartum. These cows also had a deeper and longer period of negative energy balance (NEB), poor liver function and low circulating IGF-I concentrations early postpartum. Such cows were likely to have poor reproductive function as seen in development of cystic ovaries, persistent CL and inactive ovary. Changes in serum IGF-I early postpartum may help predict both nutritional and reproductive status in dairy cattle.

Transient induction of polycystic ovary-like syndrome in immature hypothyroid rats.

Hypothyroidism in the human female is often associated with ovarian follicular cysts and hyperandrogenism, two cardinal signs of polycystic ovary syndrome. To explore the intraovarian changes that lead to follicular cyst formation in hypothyroidism, we have created a prepubertal hypothyroid rat model. These hypothyroid rats are hyperandrogenic and develop transient ovarian follicular cysts. Hypothyroidism in newborn rats was induced by providing the lactating dams with 0.04% propylthiouracil (PTU)-containing water. Subsequently, female rats were weaned and kept on PTU-containing water. On Day 25 of age, the rats were primed with 15 international units of pregnant mare's serum gonadotropin (PMSG) in 100 microl of phosphate buffered saline. Two days later, to initiate pseudopregnancy, they were injected with five international units of human chorionic gonadotropin (hCG). The animals were sacrificed at appropriate times, and blood and ovaries were collected for analyses. Control experiments were done with euthyroid rats. Two days after PMSG injection, well-developed antral follicles were observed in both the hypothyroid and euthyroid rats. Two days after hCG injection, while the euthyroid rat ovaries, as expected, contained numerous corpora lutea (CL), the hypothyroid rat ovaries still retained antral follicles. Some of these follicles with degenerating oocytes showed signs of luteinization. By 3-4 days post-hCG injection, the hypothyroid rat ovaries developed cystic follicles. By Day 6, however, the hypothyroid rat ovaries were indistinguishable from those of the euthyroid rats. Although serum testosterone concentrations were significantly elevated in the hypothyroid rats on Days 1-3, progesterone concentrations were not significantly different from the euthyroid animals. However, by Days 8-14, the hypothyroid rats had significantly higher serum progesterone concentrations. This model will be useful for investigating the intraovarian biochemical changes that lead to follicular cyst development in response to acute gonadotropin treatment.

Changes in plasma concentrations of gonadotropins and steroid hormones during the formation of bovine follicular cysts induced by the administration of ACTH.

Bovine follicular cysts were induced by treatments with ACTH (3 mg, im) daily for 14 days beginning in the late luteal phase. Cortisol concentrations in plasma significantly increased after ACTH treatments. During the formation of follicular cysts induced by the injections of ACTH, mean plasma concentrations of progesterone were significantly higher than those in the untreated preovulatory period, while mean plasma concentrations of estradiol-17 beta were significantly lower. During the treatment period, mean plasma concentrations of LH and FSH remained low, and the preovulatory surges of LH and FSH did not occur. Suppressed concentrations of LH and FSH might be caused by the increases in secretions of cortisol and progesterone, and by the decrease in secretion of estradiol-17 beta.

[Effect of proserine on the levels of steroid hormones in cows]. / Vliianie prozerina na soderzhanie steroidnykh gormonov u korov.

Stimulation of cholinergic processes by neostigmine methylsulfate results in a reliable increase of the progesterone and estradiol content in blood of cows 11-15 days after calving. In the case of hypertrophy of ovaries increase of the progesterone content is not followed by an increase of estradiol content that, apparently, decreases the content of luteohormones. In animals with high content of progesterone with persistent yellow body of ovaries the injection of neostigmine methylsulfate decreases the content of this hormone and with follicular cysts of ovaries the low content of progesterone increases. Hence, intensification of cholinergic processes normalizes the content of sexual hormones. The known trophic function of progesterone appears to be one of the manifestations of common protective-trophic function of the nervous system performed by the cholinergic processes. Therefore, the progesterone effect can be regarded as a starting one in the neurotrophic regulation of sexual hormones.