Ovarian insufficiency impairs glucose-stimulated insulin secretion through activation of hypothalamic de novo ceramide synthesis.

Oestrogens regulate body weight through their action on hypothalamus to modulate food intake and energy expenditure. Hypothalamic de novo ceramide synthesis plays a central role on obesity induced by oestrogen deficiency. Depletion in oestrogens is also known to be associated with glucose intolerance, which favours type 2 diabetes (T2D). However, the implication of hypothalamic ceramide in the regulation of glucose homeostasis by oestrogen is unknown. Here, we studied glucose homeostasis and insulin secretion in ovariectomized (OVX) female rats. OVX induces body weight gain associated with a hypothalamic inflammation and impaired glucose homeostasis. Genetic blockade of ceramide synthesis in the ventromedial nucleus of the hypothalamus (VMH) reverses hypothalamic inflammation and partly restored glucose tolerance induced by OVX. Furthermore, glucose-stimulated insulin secretion (GSIS) is increased in OVX rats due to a raise of insulin secretion second phase, a characteristic of early stage of T2D. In contrast, GSIS from isolated islets of OVX rats is totally blunted. Inhibition of ceramide synthesis in the VMH restores GSIS from isolated OVX islets and represses the second phase of insulin secretion. Stimulation of oestrogen receptor α (ERα) by oestradiol (E2) down-regulates ceramide synthesis in hypothalamic neuronal GT1-7 cells but no in microglial SIM-A9 cells. In contrast, genetic inactivation of ERα in VMH upregulates ceramide synthesis. These results indicate that hypothalamic neuronal de novo ceramide synthesis triggers the OVX-dependent impairment of glucose homeostasis which is partly mediated by a dysregulation of GSIS.

Research on the establishment of chronic stress-induced premature ovarian failure the rat model and effects of Chinese medicine Muniziqi treatment.

The purposes of this study were to establish and to explore the biological basis of the chronic stress-induced premature ovarian failure (POF) model and to explore the therapeutic effects of the traditional Chinese medicine Muniziqi. Sexually matured female Sprague-Dawley rats were fed with spinach and cilantro in cold and wet conditions for about 20 weeks until a chronic stress (CS) model was established. The CS rats were divided into a POF stress model group and a stress model group according to weekly biological characteristics and hormone level detection ( luteinizing hormone [LH], follicle stimulating hormone [FSH], and estrogen [E2]). To investigate the therapeutic effect of Muniziqi, the POF disease stress model group was divided into the high-, medium-, and low-drug intervention groups. The results showed that chronic stresses (special food, cold, damp) can lead to POF disease. The traditional Chinese medicine Muniziqi could not only improve the reproductive hormone level disorder, but also improve the function of the hypothalamus-pituitary-ovarian axis. The underlying mechanism may be a change in the E2, LH, and FSH hormone levels in serum and lower expression of ovarian premature aging-related protein PFN-1.

Premature ovarian failure of autoimmune etiology in 46XX patients: is there a hope?

OBJECTIVES: To evaluate the efficacy of live bee stings at fertility points and acupuncture in treating symptoms and managing infertility in premature ovarian failure (POF) of autoimmune etiology. PATIENTS AND METHODS: Patients with primary POF were allocated randomly into two groups: group I: subjected to acupuncture at specific fertility points and group II: subjected to live bee stings at sites of fertility points. RESULTS: A total of 24 cases show significant reduction of Follicle stimulating hormone (FSH) level to normal range with gradual decline over the study duration: 13 cases in group I and 11 cases in group II. Eight cases got pregnant while the other 13 cases regained normal menses but still infertile. CONCLUSIONS: Both bee sting therapy and acupuncture were effective in reduction of FSH levels with restoration of regular menstrual patterns and restoration of fertility. The bee sting therapy was superior in the pregnancy rate, while acupuncture was superior in alleviation of symptoms.

Role of Trace Elements, Oxidative Stress and Immune System: a Triad in Premature Ovarian Failure.

The risk of premature ovarian failure (POF) increases in association with alteration in immunological parameters and oxidative stress (OS). Adequate intake of trace elements is required for antioxidant property and immune defense mechanism. The aim of this study was to explore the involvement of trace elements, OS, and immunological parameters in POF. This was a cross-sectional, case-control study, involving 65 participants divided into the POF (n = 35) and control (n = 30) groups. Serum levels of Se, Zn, and Cu were determined along with hormonal, OS, and immunological markers. POF group had significantly lower levels of Zn, Cu, Se, and Zn:Cu ratio. However, Se:Cu ratio was not significant between the groups. FSH and LH levels were negatively correlated with Zn and Cu levels and positively correlated with Se levels. Estrogen levels were negatively correlated with all the studied trace elements. Inter-element association between Zn and Se was significant in POF (r = - 0.39, p = 0.02) compared to control group (r = - 0.078, p = 0.65). In all the POF patients, SOD and GPx activities were significantly (p < 0.05) lower and MDA level was higher (p > 0.05) than control group. B cell marker CD19 was significantly (p < 0.0001) high in POF group. There are involvement of trace elements in hormonal regulation and antioxidant defense mechanism, which once gets altered leads to high ROS generation and affect functions of the immune system. Exaggereative immune system causing higher expression of B cell associated markers (CD19) leading to autoimmune condition in POF.

Very low doses of heavy oxygen ion radiation induce premature ovarian failure.

Astronauts are exposed to charged particles during space travel, and charged particles are also used for cancer radiotherapy. Premature ovarian failure is a well-known side effect of conventional, low linear energy transfer (LET) cancer radiotherapy, but little is known about the effects of high LET charged particles on the ovary. We hypothesized that lower LET (16.5 keV/µm) oxygen particles would be less damaging to the ovary than we previously found for iron (LET = 179 keV/µm). Adult female mice were irradiated with 0, 5, 30 or 50 cGy oxygen ions or 50 cGy oxygen plus dietary supplementation with the antioxidant alpha lipoic acid (ALA). Six-hour after irradiation, percentages of ovarian follicles immunopositive for γH2AX, a marker of DNA double strand breaks, 4-HNE, a marker of oxidative lipid damage and BBC3 (PUMA), a proapoptotic BCL-2 family protein, were dose dependently increased in irradiated mice compared to controls. One week after irradiation, numbers of primordial, primary and secondary follicles per ovary were dose dependently decreased, with complete absence of follicles in the 50 cGy groups. The ED50 for primordial follicle destruction was 4.6 cGy for oxygen compared to 27.5 cGy for iron in our previous study. Serum FSH and LH concentrations were significantly elevated in 50 cGy groups at 8 week. Supplementation with ALA mitigated the early effects, but not the ultimate depletion of ovarian follicles. In conclusion, oxygen charged particles are even more potent inducers of ovarian follicle depletion than charged iron particles, raising concern for premature ovarian failure in astronauts exposed to both particles during space travel.

Clinical application of dehydroepiandrosterone in reproduction: A review of the evidence.

The effect of dehydroepiandrosterone (DHEA) therapy on improvement of reproduction outcome is uncertain. Many earlier studies have shown conflicting results. Therefore, a review of the literature is needed to explore the role of DHEA in reproduction. We conducted a literature search of MEDLINE (Ovid) and Pub-Med (2000-June 2014) for all relevant articles that included the terms "dehydroepiandrosterone," "DHEA," and "in vitro fertilization." Among the search-identified articles, seven prospective self-controlled studies and four retrospective case-control studies showed DHEA as an adjuvant therapy able to improve in vitro fertilization outcomes in poor responders (women with diminished ovarian reserve and/or poor ovarian response). However, four randomized controlled trials did not support the benefit of DHEA therapy for poor responders. By contrast, one prospective randomized study showed that DHEA might be beneficial to reproduction in women without diminished ovarian reserve (normal responders). In summary, a review of the previously published studies does not provide clear evidence that DHEA can be a useful treatment to improve ovarian function in poor responders.

Effect of inter-cycle interval on oocyte production in humans in the presence of the weak androgen DHEA and follicle stimulating hormone: a case-control study.

BACKGROUND: In various animal models androgens have been demonstrated to enhance follicle stimulating hormone (FSH) activity on granulosa cells during small growing follicle stages. To assess whether similar synergism may also exist in humans we investigated women on androgen (dehydroepiandrosterone, DHEA) supplementation with varying concomitant FSH exposure. METHODS: In a case controlled cohort study we determine if time interval between IVF cycles of IVF treatment with FSH had an effect on ovarian response to ovulation induction in women supplemented with DHEA. Among 85 women with known low functional ovarian reserve (LFOR), supplemented with DHEA, and undergoing at least 3 consecutive IVF cycles, 68 demonstrated short (<120 days) intervals between repeated cycles (Group 1) and were, therefore, considered to have consistent FSH exposure. In contrast 17 women (Group 2) demonstrated long (>=120 days) intervals between repeated cycles and, therefore, were considered to demonstrate inconsistent FSH exposure. Trends in oocyte yields were compared between these groups, utilizing mixed model repeated measures ANOVA, adjusted for initial age and FSH dose. RESULTS: Only women in Group I demonstrated a linear increase in oocyte yields across their three cycles of treatments (F=7.92; df 1, 68.6; p=0.017). Moreover, the analysis revealed a significant interaction between the two patient groups and cycle number for retrieved oocytes (F=6.32, df=2, 85.9, p=0.003). CONCLUSIONS: This study offers preliminary confirmatory evidence that repeated short interval exposure to androgens in combination with FSH improves human FOR. A higher level of evidence will require prospectively randomized studies.

The impact of androgen metabolism and FMR1 genotypes on pregnancy potential in women with dehydroepiandrosterone (DHEA) supplementation.

BACKGROUND: For decades androgens have been considered detrimental to follicle maturation. Animal studies now suggest that they are essential for normal folliculogenesis. Especially in women with premature ovarian aging (POA), recent IVF data in humans are supportive. The literature also suggests an association between recently reported ovarian genotypes of the FMR1 gene and ovarian aging patterns. We, therefore, attempted to determine a potential difference in androgen concentrations and androgen interactions in women with POA who do or do not become pregnant while undergoing androgen supplementation, and whether androgen concentrations and pregnancy chances are affected by FMR1 genotypes. METHODS: We longitudinally assessed androgen metabolism in 91 women with POA, following pre-supplementation with micronized dehydroepiandrosterone (DHEA) prior to IVF. IVF outcomes were assessed based on androgen levels and ovarian FMR1 genotypes. RESULTS: The mean age of the women was 39.8 ± 4.4 years; the clinical pregnancy rate was 25.3%. Total androgen concentrations were not associated with pregnancy; however, in women with abnormal FMR1 genotypes, but not those with the normal genotype, free testosterone significantly affected clinical pregnancy potential (ß = 1.101, SE ± 0.508, P = 0.03). At the start of the IVF cycle, interactions of DHEA with total and free testosterone also significantly affected subsequent pregnancy rates (ß = -0.058, SE ± 0.023, P = 0.01 and ß = -0.496, SE ± 0.197, P = 0.012). CONCLUSIONS: Androgen interactions significantly influence IVF pregnancy rates in women with POA, with the impact of total androgens on cycle outcomes varying according to FMR1 genotypes. These observations suggest that the effectiveness of androgen supplementation in women with POA varies based on FMR1 genotypes, and defines androgen deficiency as a subset of diminished ovarian reserve.

Premature ovarian failure and body composition changes with adjuvant chemotherapy for breast cancer.

OBJECTIVE: Premature ovarian failure and weight gain are both common in women receiving adjuvant chemotherapy for breast cancer. The objective of this preliminary analysis was to characterize changes in weight and body composition in premenopausal women receiving adjuvant chemotherapy for early stage breast cancer and investigate whether these changes were associated with chemotherapy-induced ovarian failure (CIOF). METHODS: The body composition of 43 premenopausal women with stage I or II breast cancer was measured using dual-energy x-ray absorptiometry within 4 weeks before beginning chemotherapy and after 12 months from baseline. At 12 months, the CIOF was determined using the history of amennorhea for 3 months or more and serum follicle-stimulating hormone. RESULTS: Of the 43 women, 30 (70%) developed CIOF by the 12-month follow-up. Significant weight gain occurred in women with and without CIOF and consisted of fat but not lean mass in the trunk and legs. In women who developed CIOF, truncal fat increased by a median of 1.8 kg (P = 0.0004), whereas truncal lean mass decreased by 0.6 kg (P = 0.02). Women who retained ovarian function gained a median of 0.9 kg (P = 0.06) in truncal fat with no significant change in truncal lean mass. Women with CIOF tended to lose lean mass. Loss of total body lean mass was directly correlated with the decrease in bone density as measured by bone mineral density at the femoral neck (Spearman correlation coefficient, 0.4; P = 0.03). Energy intake decreased similarly in women with and without CIOF (-184 vs -290 kcal, respectively; P = 0.77). CONCLUSIONS: The results of this small preliminary analysis suggest that body composition changes in women receiving adjuvant chemotherapy for breast cancer include an increase in fat mass in the trunk and leg regions without an increase in fat-free mass. Future research with a larger study cohort and longer follow-up is needed to further investigate the role of CIOF in body composition changes in women with breast cancer. Further research is also needed to evaluate the potential effects of body composition changes on breast cancer outcomes.

Evaluation of bone mineral density in premature ovarian failure.

This study was performed to evaluate whether or not early menopause and premature ovarian failure can cause an increased risk of osteoporosis. The bone mineral density (BMD) of the 2nd and 4th lumbar spine as well as femoral neck in 29 cases with secondary amenorrhea were compared with a reference data using a dual-energy X-ray absorptiometry on a bone densitometer: Serum levels of luteinizing hormone, follicular stimulating hormone, calcium and phosphorus were also measured. Both in 20-29 years and in 30-39 years, BMD were significantly lower than their normal range as compared with a reference data from a large study of the same population (P value<0.05). At lumbar vertebrae, 2 cases had osteopenia and 17 had osteoporosis while at the femoral neck, 17 cases had osteopenia and 4 osteoporosis. Only serum levels of phosphorus had positive relationship with femoral neck BMD (P value<0.05). It may be possible to decrease fracture incidence through the early diagnosis of individuals at risk by BMD. In conclusion, our study indicates that females with early onset of menopause and premature ovarian failure had lower value of BMD in both femoral neck and lumbar vertebrae implying the need for more bone health measures.

Delayed puberty in spontaneously hypertensive rats involves a primary ovarian failure independent of the hypothalamic KiSS-1/GPR54/GnRH system.

Spontaneously hypertensive (SH) rats, extensively used as experimental models of essential human hypertension, display important alterations in the neuroendocrine reproductive axis, which manifest as markedly delayed puberty onset in females but whose basis remains largely unknown. We analyze herein in female SH rats: 1) possible alterations in the expression and function of KiSS-1/GPR54 and GnRH/GnRH-receptor systems, 2) the integrity of feedback mechanisms governing the hypothalamic-pituitary-ovarian axis, and 3) the control of ovarian function by gonadotropins. Our data demonstrate that, despite overtly delayed puberty, no significant decrease in hypothalamic KiSS-1, GPR54, or GnRH mRNA levels was detected in this strain. Likewise, in vivo gonadotropin responses to ovariectomy and systemic kisspeptin-10 or GnRH administration, as well as in vitro gonadotropin responses to GnRH, were fully preserved in SH rats. Moreover, circulating LH levels were grossly conserved during prepubertal maturation, whereas FSH levels were even enhanced from d 20 postpartum onwards. In striking contrast, ovarian weight and hormone (progesterone and testosterone) responses to human chorionic gonadotropin (CG) in vitro were profoundly decreased in SH rats, with impaired follicular development and delayed ovulation at puberty. Such reduced hormonal responses to human CG could not be attributed to changes in LH/CG or FSH-receptor mRNA expression but might be linked to blunted P450scc, 3beta-hydroxy steroid dehydrogenase, and aromatase mRNA levels in ovaries from SH rats. In conclusion, our results indicate that the expression and function of KiSS-1/GPR54 and GnRH/GnRH-receptor systems is normal in SH rats, whereas ovarian development, steroidogenesis, and responsiveness to gonadotropins are strongly compromised.

Effects of aging and gonadal failure on the hypothalamic-pituitary axis in women.

OBJECTIVE: Our aim was to determine the effect of aging on the hypothalamic-pituitary-gonadal axis function. STUDY DESIGN: We studied 9 women aged 25 to 40 years with well-defined idiopathic premature ovarian failure and compared them with 8 women aged 51 to 70 years who had age-appropriate menopause. All women underwent 24 hours of frequent blood sampling every 10 minutes before and after replacement with transdermal estradiol targeted to achieve serum concentrations of approximately 100 pg/ml. RESULTS: In the absence of estrogen exposure, women with premature ovarian failure demonstrated a greater 24-hour mean luteinizing hormone concentration compared with that in the older women with age-appropriate menopause (32.3+/-4.3 mlU/ml vs 19.2+/-2.4 mlU/ml, p=0.0001). Despite the lesser luteinizing hormone serum levels in the older group, the luteinizing hormone pulse frequency per 24 hours was similar (22.1+/-3.0 pulses per 24 hours in prematurely menopausal women vs 21.9+/-2.5 pulses per 24 hours in the older postmenopausal women, p=0.94). When exposed to estrogen, mean luteinizing hormone concentrations decreased to 11.6+/-2.7 mlU/ml in prematurely menopausal women versus 4.4+/-1.0 mlU/ml in older postmenopausal women, p=0.017. Both groups had suppressed mean luteinizing hormone secretion compared with their paired, non-estradiol-exposed studies, p=0.0001. Frequency of luteinizing hormone pulsations was reduced to 16.5+/-3.5 pulses per 24 hours in prematurely menopausal women exposed to estradiol (p < 0.0058, compared with non-estradiol-exposed women). Further reduction was observed in older postmenopausal women (11.5+/-1.1 pulses per 24 hours, p=0.0001, compared with nonestradiol exposure, and p=0.0125, vs prematurely menopausal, estradiol-exposed women). Pulse amplitude was suppressed in both prematurely menopausal women (5.6+/-0.5 mlU/ml to 2.3+/-0.5 mlU/ml, p=0.0001) and older postmenopausal women (3.6+/-0.4 mlU/ml to 2.3+/-0.6 mlU/ml p=0.04) in the presence of estradiol. Although luteinizing hormone pulse amplitudes were greater in the women with premature menopause in the absence of estradiol (p=0.0028) compared with those in older postmenopausal women, pulse amplitudes became similar in the presence of estradiol. Parallel changes in mean follicle-stimulating hormone were observed. Women with premature ovarian failure had a mean follicle-stimulating hormone level of 71.1+/-9.4 mlU/ml that was suppressed to 18.0+/-4.1 mlU/ml after estradiol exposure (p=0.0001); values in older postmenopausal women were 45.9+/-6.0 and 10.3+/-2.0, respectively (p=0.0001). Although the women with premature ovarian failure secreted more follicle-stimulating hormone in the absence and presence of estradiol, only the former situation was statistically significant (p=0.0008 and p=0.23, respectively). CONCLUSIONS: These data suggest that there is an age-related decrease in gonadotropin secretion that may be hypothalamic or pituitary in origin. There is less luteinizing hormone secreted in women older than age 50. There is greater suppression of luteinizing hormone and follicle-stimulating hormone secretion by estradiol in aged women. Thus these data indicate that postmenopausal hormone changes involve central hypothalamic-pituitary alterations, as well as ovarian changes.