Reduction in oocyte number following prenatal exposure to a diet high in galactose

Classical Hereditary galactosemia: findings in patients and animal models

Classic galactosemia is a rare inborn error of metabolism that affects the metabolism of galactose, a sugar derived from milk and derivates. Classic galactosemia is caused by variants of the GALT gene, which lead to absent or misfolded forms of the ubiquitously present galactose-1-phosphate uridylyltransferase enzyme (GALT) driving galactose metabolites to accumulate, damaging cells from neurons to hepatocytes. The disease has different prevalence around the world due to different allele frequencies among populations and its symptoms range from cognitive and psychomotor impairment to hepatic, ophthalmological, and bone structural damage. The practice of newborn screening still varies among countries, dairy restriction treatment is a consensus despite advances in preclinical treatment strategies. Recent clinical studies in Duarte variant suggest dairy restriction could be reconsidered in these cases. Despite noteworthy advances in the classic galactosemia understanding, preclinical trials are still crucial to fully understand the pathophysiology of the disease and help propose new treatments. This review aims to report a comprehensive analysis of past studies and state of art research on galactosemia screening, its clinical and preclinical trials, and treatments with the goal of shedding light on this complex and multisystemic innate error of the metabolism.

Ovarian Reserve Disorders, Can We Prevent Them? A Review

The ovarian reserve is finite and begins declining from its peak at mid-gestation until only residual follicles remain as women approach menopause. Reduced ovarian reserve, or its extreme form, premature ovarian insufficiency, stems from multiple factors, including developmental, genetic, environmental exposures, autoimmune disease, or medical/surgical treatment. In many cases, the cause remains unknown and resulting infertility is not ultimately addressed by assisted reproductive technologies. Deciphering the mechanisms that underlie disorders of ovarian reserve could improve the outcomes for patients struggling with infertility, but these disorders are diverse and can be categorized in multiple ways. In this review, we will explore the topic from a perspective that emphasizes the prevention or mitigation of ovarian damage. The most desirable mode of fertoprotection is primary prevention (intervening before ablative influence occurs), as identifying toxic influences and deciphering the mechanisms by which they exert their effect can reduce or eliminate exposure and damage. Secondary prevention in the form of screening is not recommended broadly. Nevertheless, in some instances where a known genetic background exists in discrete families, screening is advised. As part of prenatal care, screening panels include some genetic diseases that can lead to infertility or subfertility. In these patients, early diagnosis could enable fertility preservation or changes in family-building plans. Finally, Tertiary Prevention (managing disease post-diagnosis) is critical. Reduced ovarian reserve has a major influence on physiology beyond fertility, including delayed/absent puberty or premature menopause. In these instances, proper diagnosis and medical therapy can reduce adverse effects. Here, we elaborate on these modes of prevention as well as proposed mechanisms that underlie ovarian reserve disorders.

SRT1720 plays a role in oxidative stress and the senescence of human trophoblast HTR8/SVneo cells induced by D-galactose through the SIRT1/FOXO3a/ROS signalling pathway

D-galactose (D-gal) is a reducing sugar widely distributed in food. In a pregnant animal model exposed to D-gal, D-gal was found to have toxic effects on both the mother and foetus through oxidative stress. However, little is known about the effect of D-gal exposure on the placenta and its underlying mechanism. In this study, we evaluated the effects of D-gal on HTR8/SVneo cells and the mechanisms in vitro. In the present study, the activity of HTR8/SVneo human trophoblasts decreased in a time- and concentration-dependent manner after exposure to D-gal. D-gal resulted in premature senescence of HTR8/SVneo cells, as confirmed by assessing β-galactosidase (SA-β-gal) activity and the expression of senescence-related factor p21. We also verified the damage of oxidative stress induced by D-gal by measuring the expression of reactive oxygen species (ROS), sirtuin 1 (SIRT1) and forkhead box O (FOXO) 3a. SRT1720, as a SIRT1 activator, mitigated D-gal-induced oxidative stress and senescence by upregulating SIRT1 and FOXO3a expression and reducing ROS production. Our data suggest that D-gal may induce HTR8/SVneo premature ageing through the SIRT1/FOXO3a/ROS signalling pathway mediated by oxidative stress and that SIRT1 protects cells from this damage.

Pathophysiology and management of classic galactosemic primary ovarian insufficiency

Classic galactosemia is an inborn error of carbohydrate metabolism associated with early-onset primary ovarian insufficiency (POI) in young women. Our understanding of the consequences of galactosemia upon fertility and fecundity of affected women is expanding, but there are important remaining gaps in our knowledge and tools for its management, and a need for continued dialog so that the special features of the condition can be better managed. Here, we review galactosemic POI and its reproductive endocrinological clinical sequelae and summarize current best clinical practices for its management. Special consideration is given to the very early-onset nature of the condition in the pediatric/adolescent patient. Afterward, we summarize our current understanding of the reproductive pathophysiology of galactosemia, including the potential action of toxic galactose metabolites upon the ovary. Our work establishing that ovarian cellular stress reminiscent of endoplasmic reticulum (ER) stress is present in a mouse model of galactosemia, as well as work by other groups, are summarized.

LAY SUMMARY

Patients with the condition of classic galactosemia need to maintain a strict lifelong diet that excludes the sugar galactose. This is due to having mutations in enzymes that process galactose, resulting in the buildup of toxic metabolic by-products of the sugar. Young women with classic galactosemia often lose the function of their ovaries very early in life (termed 'primary ovarian insufficiency'), despite adherence to a galactose-restricted diet. This means that in addition to the consequences of the disease, these women also face infertility and the potential need for hormone replacement therapy. This article summarizes current strategies for managing the care of galactosemic girls and women and also what is known of how the condition leads to early primary ovarian insufficiency.

What Is the Best Regimen for Ovarian Stimulation of Poor Responders in ART/IVF?

The infertile patients with aging ovaries-also sometimes referred to as impending premature ovarian insufficiency (POI), impending premature ovarian failure (POF), or poor ovarian responders (POR), constitute a significant and increasing bulk of the patients appealing to IVF/ART. Different causes have been cited in the literature, among the identified etiologies, including chromosomal and genetic etiology, metabolic, enzymatic, iatrogenic, toxic, autoimmune, and infectious causes. Although the most successful and ultimate treatment of POI/POF/POR patients is egg donation (ED), many, if not most, of these infertile women are reluctant to consent to ED upon the initial diagnostic interview, requesting alternative solutions despite the low odds for success. Despite anecdotal case reports, no unequivocal treatment proved to be successful for these patients in prospective randomized controlled trials. Nevertheless, the addition of growth hormone (GH) to ovarian stimulation in POR with GH deficiency may improve the results of controlled ovarian hyperstimulation (COH) and the IVF success. In patients with autoimmune etiology for POR/POI, the combination of glucocorticosteroids, pituitary-ovarian suppression, and COH may be successful in achieving the desired conception.

Associations of dairy product consumption with mortality in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Italy cohort

BACKGROUND

The relation of dairy product consumption to health and mortality is controversial.

OBJECTIVES

We investigated associations of consumption of various dairy products with mortality in the Italian cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Italy study.

METHODS

Dairy product consumption was assessed by validated semiquantitative FFQs. Multivariable Cox models stratified by center, age, and sex and adjusted for confounders estimated associations of milk (total, full fat, and reduced fat), yogurt, cheese, butter, and dairy calcium consumption with mortality for cancer, cardiovascular disease, and all causes. Nonlinearity was tested by restricted cubic spline regression.

RESULTS

After a median follow-up of 14.9 y, 2468 deaths were identified in 45,009 participants: 59% from cancer and 19% from cardiovascular disease. No significant association of consumption of any dairy product with mortality was found in the fully adjusted models. A 25% reduction in risk of all-cause mortality was found for milk intake from 160 to 120 g/d (HR: 0.75; 95% CI: 0.61, 0.91) but not for the highest (>200 g/d) category of intake (HR: 0.95; 95% CI: 0.84, 1.08) compared with nonconsumption. Associations of full-fat and reduced-fat milk consumption with all-cause and cause-specific mortality were similar to those for milk as a whole.

CONCLUSIONS

In this Italian cohort characterized by low to average milk consumption, we found no evidence of a dose-response association between milk consumption and mortality and also no association of consumption of other dairy products investigated with mortality.

Insights into the Pathophysiology of Infertility in Females with Classical Galactosaemia

Classical galactosaemia (CG) (OMIM 230400) is a rare inborn error of galactose metabolism caused by the deficiency of the enzyme galactose-1-phosphate uridylyltransferase (GALT, EC 2.7.7.12). Primary ovarian insufficiency (POI) is the most common long-term complication experienced by females with CG, presenting with hypergonadotrophic hypoestrogenic infertility affecting at least 80% of females despite new-born screening and lifelong galactose dietary restriction. In this review, we describe the hypothesized pathophysiology of POI from CG, implications of timing of the ovarian dysfunction, and the new horizons and future prospects for treatments and fertility preservation.

Induced premature ovarian insufficiency by using D galactose and its effects on reproductive profiles in small laboratory animals: a systematic review

BACKGROUND

Development of a hyper-gonadotropic hypoestrogenism condition in women < 40 years, defined as premature ovarian insufficiency (POI), is the most common long-term complication in female survivors of galactosemia. In this systematic review, summarize the galactose (GAL) induced POI in rat and mice models.

METHODS

For this systematic review, we conducted a search of case control studies published from 1990 until August 2018 in PubMed/Medline, and Web of science, using the descriptors in the title/abstract field. A 'pearl growing' strategy was employed whereby, after obtaining the full text articles, reference lists of all included studies (n = 14) were reviewed for additional publications that could be used.

RESULTS

We selected and categorized 14 studies according to the time of exposure to GAL into two groups of prenatal (n = 4) and postnatal (n = 10). Findings of these studies showed that the different stages of follicular development are targeted differently by galactose exposure during the prenatal and postnatal periods: The small follicles (primordial and primary follicles) are targeted by galactose toxicity during prenatal exposure and the pre-antral and antral follicles are targeted by galactose toxicity during postnatal exposure.

CONCLUSIONS

This systematic review shows that galactose has an ovotoxicity effect that can be used to induce appropriate POI animal models only if sufficient doses, proper onset time, and duration of prenatal exposure are taken into account. An optimized model of POI induction should manifest all the required ovarian morphological, hormonal, and estrus cycle changes.

Dehydroepiandrosterone supplementation attenuates ovarian ageing in a galactose-induced primary ovarian insufficiency rat model

PURPOSE

Almost every female classic galactosemia patient develops primary ovarian insufficiency (POI). The unique pathophysiology of classic galactosemia, with a severely reduced follicle pool at an early age, requires a new therapeutic approach. This study evaluated the effect of dehydroepiandrosterone (DHEA) on ovarian tissue in a galactose-induced POI rat model.

METHODS

Pregnant rats were fed with either a normal or a 35% galactose-containing diet from day 3 of conception continuing through weaning of the litters. Galactose-exposed female offspring were further divided into 5 groups on PND21. The first group received no application. Treatment groups were fed orally by gavage once daily with sesame oil (group 2), or DHEA at doses of 0.1 mg/kg (group 3), 1 mg/kg (group 4) or 10 mg/kg (group 5) until PND70. Fertility rates of mothers with galactosemia, body weights (BWs), and ovarian weights of the litters from PND21 to PND70 were recorded. Ovarian follicle count, immunohistochemistry for proliferation and apoptosis marker expressions and TUNEL for cell death assessment were performed in offspring ovaries.

RESULTS

Decreased fertility, ovarian/body weights were observed under galactosemic conditions, together with decreased follicle number and increased atresia. Improved postnatal development, primordial follicle recruitment and follicular growth were observed after DHEA treatment. After DHEA treatment, the expression of Ki67 protein was found to be increased; elevated expression of cleaved-caspase-3 under galactosemia was found to be reduced.

CONCLUSIONS

Our data suggests that DHEA treatment may be a potentially useful clinical therapy to improve ovarian ageing in women with POI-induced by galactosemia.

Effect of genotype on galactose-1-phosphate in classic galactosemia patients

Impaired activity of galactose-1-phosphate uridyltransferase (GALT) causes classic galactosemia (OMIM 230400), characterized by the accumulation of galactose-1-phosphate (GAL1P) in patients' red blood cells (RBCs). Our recent study demonstrated a correlation between RBC GAL1P and long-term outcomes in galactosemia patients. Here, we analyze biochemical and molecular results in 77 classic galactosemia patients to evaluate the association between GALT genotypes and GAL1P concentration in RBCs. Experimental data from model organisms were also included to assess the correlation between GAL1P and predicted residual activity of each genotype. Although all individuals in this study showed markedly reduced RBC GALT activity, we observed significant differences in RBC GAL1P concentrations among galactosemia genotypes. While levels of GAL1P on treatment did not correlate with RBC GALT activities (p = 0.166), there was a negative nonlinear correlation between mean GAL1P concentrations and predicted residual enzyme activity of genotype (p = 0.004). These studies suggest that GAL1P levels in RBCs on treatment likely reflect the overall functional impairment of GALT in patients with galactosemia.

Biochemical changes and clinical outcomes in 34 patients with classic galactosemia

Impaired activity of galactose-1-phosphate uridyltransferase (GALT) causes galactosemia, an autosomal recessive disorder of galactose metabolism. Early initiation of a galactose-restricted diet can prevent or resolve neonatal complications. Despite therapy, patients often experience long-term complications including speech impairment, learning disabilities, and premature ovarian insufficiency in females. This study evaluates clinical outcomes in 34 galactosemia patients with markedly reduced GALT activity and compares outcomes between patients with different levels of mean galactose-1-phosphate in red blood cells (GAL1P) using logistic regression: group 1 (n = 13) GAL1P ≤1.7 mg/dL vs. group 2 (n = 21) GAL1P ≥ 2 mg/dL. Acute symptoms at birth were comparable between groups (p = 0.30) with approximately 50% of patients presenting with jaundice, liver failure, and failure-to-thrive. However, group 2 patients had significantly higher prevalence of negative long-term outcomes compared to group 1 patients (p = 0.01). Only one of 11 patients >3 yo in group 1 developed neurological and severe behavioral problems of unclear etiology. In contrast, 17 of 20 patients >3 yo in group 2 presented with one or more long-term complications associated with galactosemia. The majority of females ≥15 yo in this group also had impaired ovarian function with markedly reduced levels of anti-Müllerian hormone. These findings suggest that galactosemia patients with higher GAL1P levels are more likely to have negative long-term outcome. Therefore, evaluation of GAL1P levels on a galactose-restricted diet might be helpful in providing a prognosis for galactosemia patients with rare or novel genotypes whose clinical presentations are not well known.

Primary ovarian insufficiency in classic galactosemia: current understanding and future research opportunities

Classic galactosemia is an inborn error of the metabolism with devastating consequences. Newborn screening has been successful in markedly reducing the acute neonatal symptoms from this disorder. The dramatic response to dietary treatment is one of the major success stories of newborn screening. However, as children with galactosemia achieve adulthood, they face long-term complications. A majority of women with classic galactosemia develop primary ovarian insufficiency and resulting morbidity. The underlying pathophysiology of this complication is not clear. This review focuses on the reproductive issues seen in girls and women with classic galactosemia. Literature on the effects of classic galactosemia on the female reproductive system was reviewed by an extensive Pubmed search (publications from January 1975 to January 2017) using the keywords: galactosemia, ovarian function/dysfunction, primary ovarian insufficiency/failure, FSH, oxidative stress, fertility preservation. In addition, articles cited in the search articles and literature known to the authors was also included in the review. Our understanding of the role of galactose metabolism in the ovary is limited and the pathogenic mechanisms involved in causing primary ovarian insufficiency are unclear. The relative rarity of galactosemia makes it difficult to accumulate data to determine factors defining timing of ovarian dysfunction or treatment/fertility preservation options for this group of women. In this review, we present reproductive challenges faced by women with classic galactosemia, highlight the gaps in our understanding of mechanisms leading to primary ovarian insufficiency in this population, discuss new advances in fertility preservation options, and recommend collaboration between reproductive medicine and metabolic specialists to improve fertility in these women.

Fertility in adult women with classic galactosemia and primary ovarian insufficiency

OBJECTIVE

To study pregnancy chance in adult women with classic galactosemia and primary ovarian insufficiency. Despite dietary treatment, >90% of women with classic galactosemia develop primary ovarian insufficiency, resulting in impaired fertility. For many years, chance of spontaneous conception has not been considered, leading to counseling for infertility. But an increasing number of reports on pregnancies in this group questions whether current counseling approaches are correct.

DESIGN

Multicenter retrospective observational study.

SETTING

Metabolic centers.

PATIENT(S)

Adult women (aged >18 y) with confirmed classic galactosemia and primary ovarian insufficiency were included.

INTERVENTION(S)

Participants and medical records were consulted to obtain study data in a standardized manner with the use of a questionnaire.

MAIN OUTCOME MEASURE(S)

Conception opportunities, time to pregnancy, pregnancy outcome, hormone replacement therapy use, fertility counseling, and the participants' vision of fertility were evaluated. Potential predictive factors for increased pregnancy chance were explored.

RESULT(S)

Eighty-five women with classic galactosemia and primary ovarian insufficiency participated. Twenty-one women actively attempted to conceive or did not take adequate contraceptive precautions. Of these 21 women, nine became pregnant spontaneously (42.9%). This was higher than reported in primary ovarian insufficiency due to other causes (5%-10%). After a period of 12 months, a cumulative proportion of 27.8% of couples had conceived, which increased to 48.4% after 24 months and 61.3% after 27 months. Predictive factors could not be identified. A considerable miscarriage rate of 30% was observed (6 of 20 pregnancies). Although a substantial proportion of women expressed a child-wish (n = 28/53; 52.8%), the vast majority of participants (n = 43/57; 75.4%) considered conceiving to be highly unlikely, owing to negative counseling in the past.

CONCLUSION(S)

The pregnancy rate in women with classic galactosemia and primary ovarian insufficiency was higher than for women with primary ovarian insufficiency of any cause. This shifting paradigm carries significant implications for fertility counseling and potential application of fertility preservation techniques.

Ginsenoside Rg1 improves fertility and reduces ovarian pathological damages in premature ovarian failure model of mice

This study aims to investigate the effect as well as mechanism of ginsenoside Rg1 (Rg1) on premature ovarian failure (POF) induced by d-galactose (d-gal) in mice. C57BL/6 female mice were divided into four groups randomly, which were the saline group, the d-gal group, the d-gal + Rg1 group, and the Rg1 group. Body weight was recorded. Overall ovarian function including estrous cycles, sex hormone secretion, ovarian follicle development, and ovarian morphology was analyzed by H&E staining and ELISA. Effect of Rg1 on aging was determined by analyzing the activities of oxidation-associated biomarkers, pro-inflammatory cytokine secretion, expression of senescence-associated proteins, and fertility. Compared with the d-gal group, in Rg1 + d-gal group, body weight was increased significantly, estrous cycle block was released, and fertility and the morphology of ovaries were restored. And, Rg1 treatment after d-gal administration significantly reduced senescence-associated protein expression, increased the activity of total superoxide dismutase and glutathione peroxidase from bovine erythrocyte, and induced higher follicle stimulating hormone receptor protein expression. Additionally, the expression levels of malondialdehyde, interleukin-1β, tumor necrosis factor-α, and interleukin-6 were significantly decreased. Together, Rg1 improves mouse fertility and reduces ovarian pathological damage in d-gal-induced POF model possibly through enhancing anti-inflammatory and antioxidant capacities and reducing expression of senescence signal pathway proteins. Impact statement Ginsenoside Rg1 (Rg1) is a kind of natural estrogen and it has antioxidation and antiaging effects. However, whether Rg1 has effects on premature ovarian failure (POF) is still not clear. In this study, aging model induced by d-galactose was used to mimic POF. The effect and possible mechanism of Rg1 on ovary aging was investigated. We found that Rg1 treatment up-regulated the expression of follicle stimulating hormone receptor and down-regulated senescence-associated protein expression in granule cells of POF mice. Particularly, Rg1 improved fertility ability and reduced ovarian pathological damages by its antioxidative and anti-inflammation capacity. Thus, Rg1 enhances the antiaging ability of ovary and fertility ability of POF mice through enhancing the anti-inflammatory and antioxidant capacities of ovary.

Galactose and its Metabolites Deteriorate Metaphase II Mouse Oocyte Quality and Subsequent Embryo Development by Disrupting the Spindle Structure

Premature ovarian insufficiency (POI) is a frequent long-term complication of classic galactosemia. The majority of women with this disorder develop POI, however rare spontaneous pregnancies have been reported. Here, we evaluate the effect of D-galactose and its metabolites, galactitol and galactose 1-phosphate, on oocyte quality as well as embryo development to elucidate the mechanism through which these compounds mediate oocyte deterioration. Metaphase II mouse oocytes (n = 240), with and without cumulus cells (CCs), were exposed for 4 hours to D-galactose (2 μM), galactitol (11 μM) and galactose 1-phosphate (0.1 mM), (corresponding to plasma concentrations in patients on galactose-restricted diet) and compared to controls. The treated oocytes showed decreased quality as a function of significant enhancement in production of reactive oxygen species (ROS) when compared to controls. The presence of CCs offered no protection, as elevated ROS was accompanied by increased apoptosis of CCs. Our results suggested that D-galactose and its metabolites disturbed the spindle structure and chromosomal alignment, which was associated with significant decline in oocyte cleavage and blastocyst development after in-vitro fertilization. The results provide insight into prevention and treatment strategies that may be used to extend the window of fertility in these patients.

Dairy food and nutrient intake in different life periods in relation to risk of ovarian cancer

PURPOSE

High lactose intake has been suggested to increase epithelial ovarian cancer (EOC) risk. We evaluated the association between lactose consumed during specific life periods (high school, premenopause, and postmenopause) and later risk of EOC.

METHODS

We assessed the association of dairy food and nutrient intake with risk of EOC during 28 years of follow-up including 764 cases in the Nurses' Health Study (NHS) and NHSII. Cox proportional hazards regression was used to model the hazard ratios (HRs) and 95% confidence intervals (CIs) for EOC across categories of dairy food or nutrient intake. We examined dietary intake in adulthood overall, as well as during premenopausal/postmenopausal years and high school.

RESULTS

In analyses of the highest versus lowest cumulative average intake in adulthood, we observed a non-significant inverse association with skim milk intake (HR 0.76, 95% CI 0.54-1.06, p(trend) = 0.05), a non-significant inverse association with lactose intake (HR 0.87, 95% CI 0.69-1.11, p(trend) = 0.22) and no association with consumption of whole milk, dairy calcium, or dairy fat. Similar risk estimates were observed for dairy food/nutrient intake during high school, premenopause or postmenopause. Lactose intake in adulthood was inversely associated with risk of endometrioid EOC (HR 0.32, 95% CI 0.16-0.65, p(trend) < 0.001).

CONCLUSIONS

These findings do not support the hypothesis that higher lactose intake increases EOC risk. The inverse association with endometrioid tumors deserves further study.

Milk nutritional composition and its role in human health

Dairy and milk consumption are frequently included as important elements in a healthy and balanced diet. It is the first food for mammals and provides all the necessary energy and nutrients to ensure proper growth and development, being crucial in respect to bone mass formation. However, several controversies arise from consumption of dairy and milk products during adulthood, especially because it refers to milk from other species. Despite these controversies, epidemiologic studies confirm the nutritional importance of milk in the human diet and reinforce the possible role of its consumption in preventing several chronic conditions like cardiovascular diseases (CVDs), some forms of cancer, obesity, and diabetes. Lactose malabsorption symptoms and cow milk protein allergy are generally considered to be the adverse reactions to milk consumption. The present article reviews the main aspects of milk nutritional composition and establishes several associations between its nutritious role, health promotion, and disease prevention.

Fertility preservation in female classic galactosemia patients

Almost every female classic galactosemia patient develops primary ovarian insufficiency (POI) as a diet-independent complication of the disease. This is a major concern for patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The unique pathophysiology of classic galactosemia with a severely reduced follicle pool at an early age requires an adjusted approach. In this article recommendations for physicians based on current knowledge concerning galactosemia and fertility preservation are made. Fertility preservation is only likely to be successful in very young prepubertal patients. In this group, cryopreservation of ovarian tissue is currently the only available technique. However, this technique is not ready for clinical application, it is considered experimental and reduces the ovarian reserve. Fertility preservation at an early age also raises ethical questions that should be taken into account. In addition, spontaneous conception despite POI is well described in classic galactosemia. The uncertainty surrounding fertility preservation and the significant chance of spontaneous pregnancy warrant counseling towards conservative application of these techniques. We propose that fertility preservation should only be offered with appropriate institutional research ethics approval to classic galactosemia girls at a young prepubertal age.

Primary ovarian insufficiency in classic galactosemia: role of FSH dysfunction and timing of the lesion

FSH inactivity due to secondary hypoglycosylation has been suggested as a potential mechanism for primary ovarian insufficiency in classic galactosemia. To investigate the role of FSH and to gain insight in the timing of the damage, ovarian stimulation tests were performed and data on ovarian imaging collected. Fifteen patients with primary ovarian insufficiency underwent ovarian stimulation with gonadotropins. Only one patient showed a normal increase in estradiol level, all the others had a low or no estradiol response. Anti-Müllerian hormone measurement in all girls and women showed levels below the detection limit of 0.10 μg/l. Ovarian volumes were evaluated by MRI in 14 patients and compared to age matched controls, prepubertal controls and postmenopausal controls. The ovarian volumes of the galactosemic girls were smaller than those of the age matched controls (p = 0.001) and the prepubertal ovaries (p = 0.008), and did not differ significantly from postmenopausal ovarian volumes (p = 0.161). In conclusion we found no evidence that FSH inactivity plays a role in primary ovarian insufficiency in classic galactosemia. Moreover, ovarian imaging results point to an early onset of ovarian failure in this disease.

Dairy foods and nutrients in relation to risk of ovarian cancer and major histological subtypes

Inconsistent results for the role of dairy food intake in relation to ovarian cancer risk may reflect the potential adverse effects of lactose, which has been hypothesized to increase gonadotropin levels, and the beneficial antiproliferative effects of calcium and vitamin D. Using data from the New England case-control study (1,909 cases and 1,989 controls), we examined dairy foods and nutrients in relation to risk of ovarian cancer overall, histological subtypes and rapidly fatal versus less aggressive disease. We used logistic regression and polytomous logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs). In models that were simultaneously adjusted for total (dietary plus supplements) calcium, total vitamin D and lactose, we observed a decreased overall risk of ovarian cancer with high intake of total calcium [Quartile 4 (Q4, >1,319 mg/day) vs. Quartile 1 (Q1, <655 mg/day), OR = 0.62, 95% CI = 0.49-0.79]; the inverse association was strongest for serous borderline and mucinous tumors. High intake of total vitamin D was not associated overall with ovarian cancer risk, but was inversely associated with risk of serous borderline (Q4, >559 IU/day vs. Q1, <164 IU/day, OR = 0.51, 95% CI = 0.34-0.76) and endometrioid tumors (Q4 vs. Q1, OR = 0.55, 95% CI = 0.39-0.80). We found no evidence that lactose intake influenced ovarian cancer risk or that risk varied by tumor aggressiveness in the analyses of intake of dairy foods and nutrients. The overall inverse association with high intake of calcium and the inverse associations of calcium and vitamin D with specific histological subtypes warrant further investigation.

Use of dairy products, lactose, and calcium and risk of ovarian cancer - results from a Danish case-control study

BACKGROUND

A number of epidemiological studies have examined the association between use of dairy products and risk of ovarian cancer, but results are conflicting. Using data from a large Danish population-based case-control study we here further examined the association between dairy consumption, lactose, and calcium and risk of overall ovarian cancer and histological types of ovarian cancer.

MATERIAL AND METHODS

In the period 1995-1999 we included 554 women with epithelial ovarian cancer and 1554 randomly selected age-matched controls (35-79 years). All women participated in a detailed personal interview that included questions about dairy consumption. Data were analysed using multiple logistic regression models.

RESULTS

Total dairy intake was associated with ovarian cancer risk (OR = 1.11; 95% CI: 1.07-1.15 per 100 ml/day). The association was strongest for milk [OR = 1.14; 95% CI: 1.03-1.27 per glass (200 ml)/day], soured milk products [OR = 1.49; 95% CI: 1.22-1.81 per portion (250 ml)/day] and yoghurt [OR = 1.65; 95% CI: 1.22-2.23 per portion (250 ml)/day]. In contrast, intake of cheese was associated with a decreased risk [OR = 0.70; 95% CI: 0.55-0.89 for > 1 portion (100 ml)/day compared with no intake]. Intake of lactose, but not calcium, was also associated with an increased ovarian cancer risk (OR = 1.24; 95% CI: 1.10-1.40 per 10 g of lactose/day). Similar risk patterns were observed for the different histological types of ovarian cancer, indicating virtually identical aetiologies with regard to dairy intake, lactose, and calcium.

CONCLUSIONS

Our results indicate that intake of dairy products is associated with a modest increased risk of ovarian cancer. In addition, ovarian cancer development was associated with lactose intake.

Ovarian function in girls and women with GALT-deficiency galactosemia

Primary or premature ovarian insufficiency (POI) is the most common long-term complication experienced by girls and women with classic galactosemia; more than 80% and perhaps more than 90% are affected despite neonatal diagnosis and careful lifelong dietary restriction of galactose. In this review we explore the complexities of timing and detection of galactosemia-associated POI and discuss potential underlying mechanisms. Finally, we offer recommendations for follow-up care with current options for intervention.

Galactose toxicity in animals

In most organisms, productive utilization of galactose requires the highly conserved Leloir pathway of galactose metabolism. Yet, if this metabolic pathway is perturbed due to congenital deficiencies of the three associated enzymes, or an overwhelming presence of galactose, this monosaccharide which is abundantly present in milk and many non-dairy foodstuffs, will become highly toxic to humans and animals. Despite more than four decades of intense research, little is known about the molecular mechanisms of galactose toxicity in human patients and animal models. In this contemporary review, we take a unique approach to present an overview of galactose toxicity resulting from the three known congenital disorders of galactose metabolism and from experimental hypergalactosemia. Additionally, we update the reader about research progress on animal models, as well as advances in clinical management and therapies of these disorders.

Gonadal function in male and female patients with classic galactosemia

BACKGROUND

Hypergonadotropic hypoestrogenic infertility is the most burdensome complication for females suffering from classic galactosemia. In contrast, male gonadal function seems less affected. The underlying mechanism is not understood and several pathogenic mechanisms have been proposed. Timing of the lesion, prenatal or chronic post-natal, or a combination of both are not yet clear.

METHODS

This review focuses on gonadal function in males and females, ovarian imaging and histology in this disease. It is based on the literature known to the authors and a Pubmed search using the keywords galactosemia, GALT deficiency, (premature) ovarian failure/insufficiency/dysfunction, testicular function, gonadotrophins, FSH, LH (published between January 1971 and April 2009).

RESULTS

Male gonads are less affected, boys spontaneously reach puberty, although onset can be delayed. Semen quality has not been extensively studied. Several affected males are known to have fathered a child. Female gonads are invariably affected, although to a varied extent (hypergonadotropic hypoestrogenic ovarian dysfunction). Intriguingly, FSH is often already increased in infancy. Imaging usually shows hypoplastic and streak-like ovaries. Histological findings in some cases reveal the presence of morphologically normal but decreased numbers of primordial follicles, with the absence of intermediate and Graafian follicles.

CONCLUSION

Gonads in males seem less affected than in females who exhibit hypergonadotropic hypoestrogenic subfertility. FSH can be elevated in infancy, and ovarian histology sometimes shows the presence of normal primordial follicles with absence of intermediate and Graafian follicles. These findings are similar to other genetic diseases primarily affecting the ovary.

Galactose-1-phosphate uridyl transferase deficiency is not associated with Müllerian aplasia in Dutch patients

STUDY OBJECTIVE

To study whether a deficiency in galactose-1-phosphate uridyl transferase (GALT) activity of mothers was an explanation for the occurrence of Müllerian aplasia of their daughters.

DESIGN

A case control study.

SETTING

The patients were selected from the outpatient clinic of the University Medical Center Nijmegen, and compared with the general population in The Netherlands.

PARTICIPANTS

Patients (n=9) diagnosed with the syndrome of Müllerian aplasia and their mothers were included.

INTERVENTIONS

A questionnaire for medical and family history was taken, and a venous blood sample and urine were collected.

MAIN OUTCOME MEASURES

GALT activity (in blood), galactose and galactilol (in urine) were measured. Measured values were analyzed by Student's paired t-test.

RESULTS

All patients and their mothers had normal GALT activities> or =20 micromol/h/g Hb. The mean value did not differ from the mean of the normal Dutch population, which was 31.6 (SD=5.0) mumol/h/g Hb.

CONCLUSION

GALT deficiency is not an explanation for Müllerian aplasia, at least in the Dutch population.

Premature ovarian failure: etiology and possible prevention

Premature ovarian failure (POF) is defined as premature menopause in women younger than 40 years of age. This heterogeneous disorder (occurring in 1% of women younger than 40 of age and 0.1% of those younger than 30 years of age), is associated with many and different etiologies, such as chromosomal, genetic, enzymatic, iatrogenic, metabolic and infectious causes. Only in less than half of cases can the etiologic cause be identified. In the last decade, many genetic abnormalities were identified in association with POF, mainly owing to the transgenic mice models, which enabled the study of phenotype in these null mice. Iatrogenic POF after chemotherapy has gained worldwide interest owing to significantly improved survival in the last three decades and the ability to preserve future fertility and ovarian function in many young women who are survivors of young-age malignancy. The attempts of in vitro fertilization-assisted reproductive technology and embryo or unfertilized ova cryopreservation, combined with ovarian tissue cryopreservation and coadministration of gonadotrophin-releasing hormone agonists in parallel with chemotherapy may maximize future fertility and minimize long-term POF in these women.

Galactosemia and amenorrhea in the adolescent

Hereditary galactosemia is a biochemical genetic disease due to a deficiency of galactose-1-phosphate uridyltransferase (GALT) enzyme activity (OMIM 606999). Acute manifestations occur in the neonatal period and are, with rare exceptions, related to lactose ingestion. They include poor feeding and growth, emesis, jaundice, liver disease, bleeding diathesis, anemia, renal tubulopathy, cataracts, encephalopathy and death from E. coli sepsis. Chronic manifestations, which also develop in prospectively treated patients, involve (a) the brain, resulting in delayed language acquisition, speech defects, and learning problems, and (b) the ovary, in the majority of females, producing hypergonadotropic hypogonadism. The serum FSH level is elevated in infancy/early childhood in many, but not all patients with a severe phenotype. There are few reports of patients with classic galactosemia having undergone pregnancy, labor, and delivery. The pathologic findings in the ovary, including a persistence of primordial follicles and streak gonads, have been variable. The etiology of primary ovarian insufficiency (POI) in galactosemia is unknown. Clinical surveillance includes screening for abnormalities in ovarian function at an early age. Treatment consists of estrogen/progesterone supplementation at the appropriate age. Reduced BMD has been reported. Future research is needed (1) to delineate the mechanisms behind reduced ovarian function in these young women; (2) to determine the timing of the lesion: prenatal, postnatal, and both pre- and postnatal; (3) to determine whether elevated galactose-1-phosphate is both necessary and sufficient to induce primary ovarian insufficiency; and (4) to understand the mechanism(s) behind the reduced BMD seen in children and adolescents with galactosemia.

Biomarkers of ovarian function in girls and women with classic galactosemia

OBJECTIVE

To determine whether premature ovarian insufficiency (POI) associated with classic galactosemia results from a true impairment of ovarian function or from aberrant FSH.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PATIENT(S)

Study subjects included 35 girls and women with galactosemia and 43 control girls and women between the ages of <1 and 51 years.

INTERVENTION(S)

Blood sampling and medical and reproductive histories were obtained.

MAIN OUTCOME MEASUREMENT(S)

We determined FSH and anti-Müllerian hormone (AMH) levels in subjects with and without classic galactosemia. FSH bioactivity was measured in a subset of girls and women with and without galactosemia who were not on hormone therapy.

RESULT(S)

FSH levels were significantly higher and AMH levels were significantly lower in our galactosemic cases relative to controls. FSH bioactivity did not significantly differ between cases and controls.

CONCLUSION(S)

Close to 90% of girls and women with classic galactosemia have a profound absence of ovarian function, a deficit that is evident shortly after birth, if not before. These patients have no evidence of abnormally functioning FSH. AMH levels can be assessed before menarche or after initiation of hormone therapy and may supplement FSH as a useful blood biomarker of ovarian function for patients with classic galactosemia.

Fertility and impact of pregnancies on the mother and child in classic galactosemia

Despite the high prevalence of premature ovarian failure (POF) and subsequent infertility in galactosemic women, spontaneous pregnancies occur and may not be as rare as is generally assumed. This is important for counseling these women on fertility. The purpose of this review is to assess the occurrence and predicting factors of pregnancy, and to evaluate the impact of pregnancy on the mother's and child's health. The female Dutch galactosemia population (age > 18 years) was studied, and a literature search on articles reporting pregnancy in galactosemic women, published between January 1971 and December 2007, was performed. Twenty-two galactosemic women were studied. Nine women have tried to conceive, of which 4 were successful. Three mothers were diagnosed with POF before the first pregnancy and/or in between pregnancies. In literature, 50 pregnancy reports were found. In 10 pregnancy reports from the literature, the mother's genotype is known. Four women were homozygous for the Q188R mutation, which equals the incidence of 40-45% of classic galactosemia caused by this mutation. This study challenges the current opinion that the chance of becoming pregnant is small in classic galactosemia. Despite POF in most galactosemic women, pregnancies do occur. The genotype and GALT-activity do not seem to predict the chance of becoming pregnant, whereas the occurrence of spontaneous menarche might. No evidence for the need of additional check-ups during the pregnancy and puerperium was found. Elevations in galactose-metabolites do occur, but without evidence of clinical impact for the mother or the child, although possible long-term effects have not been thoroughly investigated.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to summarize the purported causes and sequelae of galactosemia, explain the possible sequelae of galactosemia, distinguish alterations of the ovary and the hypothalamic-pituitary axis, identify the frequency of pregnancy and the possible outcome of the offspring, and outline dietary management of patients with galactosemia.

Effects of carbosulfan administration schedules on estrous cycle and follicular dynamics in albino mice

Carbosulfan an acaricide was orally administrated at 48 mg/kg body weight/day to female swiss albino mice for 5, 10, 20 and 30 d. Daily vaginal smear and body weight was recorded. The mice were sacrificed by cervical dislocation after 24 h of terminal exposure to carbosulfan. The results of the present study indicated that there was a significant decrease in the number of estrous cycle and phases with a concomitant increase in the length of the estrous cycle and diestrus phase with carbosulfan treatment for 10, 20, and 30 d. There was a significant decrease in the weight of the ovary, uterus, number of healthy follicles and increase in the number of atretic follicles with 20 and 30 d carbosulfan treatment when compared with the control. There was a significant decrease in the level of sialic acid with an increase in the level of cholesterol by carbosulfan treatment for 20 and 30 d. The decreased level of sialic acid indicates the decreased level of circulating FSH/LH. The ovary 3beta HSD activity decreased significantly with 20 and 30 d carbosulfan exposure mice indicating its effect on steroidogenesis, when compared to controls. The above findings may be due to direct effect on the ovary or on the gonadotrophins secretion via central nervous mechanism in mice.

ARHI: A new target of galactose toxicity in Classic Galactosemia

In humans, deficiency of galactose-1-phosphate uridyltransferase (GALT) activity can lead to a potentially lethal disease called Classic Galactosemia. Although a galactose-restricted diet can prevent the acute lethality associated with the disorder, chronic complications persist in many well-treated patients. Approximately 85% of young women with Classic Galactosemia experience hypergonadotropic hypogonadism and premature ovarian failure (POF). Others suffer from mental retardation, growth restriction, speech dyspraxia, and ataxia. Despite decades of intense biochemical characterization, little is known about the molecular etiology, as well as the chronology of the pathological events leading to the poor outcomes. Several hypotheses have been proposed, most of which involved the accumulation of the intermediates and/or the deficit of the products, of the blocked GALT pathway. However, none of these hypotheses satisfactorily explained the absence of patient phenotypes in the GALT-knockout mice. Here we proposed that the gene encoded the human tumor suppressor gene aplysia rashomolog I (ARHI) is a target of toxicity in Classic Galactosemia, and because ARHI gene is lost in rodents in through evolution, it thus accounts for the lack of clinical phenotypes in the GALT-knockout mice.

Milk, dairy products and cancer risk (Italy)

BACKGROUND

Inconclusive information is available on the potential role of milk and dairy products on the risk of cancer at several sites.

METHODS

We analyzed data from a large and integrated network of hospital-based case-control studies in Italy on cancers of the oral cavity and pharynx (598 cases, 1491 controls), oesophagus (304 cases, 743 controls), colorectum (1953 cases, 4154 controls), larynx (460 cases, 1088 controls), breast (2569 cases, 2588 controls), ovary (1031 cases, 2411 controls) and prostate (1294 cases, 1451 controls).

RESULTS

Multivariate odds ratio (OR) for the highest consumption level of any type of milk was 0.94 (95% confidence interval, CI: 0.61-1.33) for cancers of the oral cavity and pharynx, 1.20 (95% CI: 0.76-1.90) for oesophageal, 0.77 (95% CI: 0.62-0.96) for colon, 0.80 (95% CI: 0.60-1.05) for rectal, 0.83 (95% CI: 0.56-1.21) for laryngeal, 0.91 (95% CI: 0.76-1.10) for breast, 0.89 (95% CI: 0.68-1.15) for ovarian and 1.08 (95% CI: 0.84-1.37) for prostate cancer. A significant trend in risk was found for colon cancer only. Inverse associations were observed between consumption of skim milk and cancers of colon (OR=0.84; 95% CI: 0.73-0.97), rectum (OR=0.76; 95% CI: 0.64-0.91), breast (OR=0.87; 95% CI: 0.77-0.98) and ovary (OR=0.77; 95% CI: 0.66-0.91). Conversely, whole milk consumption was directly associated with cancer of the rectum (OR=1.22; 95% CI: 1.03-1.44) and ovary (OR=1.25; 95% CI: 1.07-1.46). High consumption of cheese was inversely related to colon cancer risk (OR=0.80; 95% CI: 0.67-0.95).

CONCLUSIONS

There was a modest direct association between milk and dairy products and prostate cancer, and a moderate inverse one for colorectal cancer. However, our findings indicate that milk and dairy products are not strong risk indicators for any of the cancers considered.

Relationship Between Calcium, Lactose, Vitamin D, and Dairy Products and Ovarian Cancer

Few prospective studies of the relationship between intake of dairy foods, calcium, vitamin D, and lactose and ovarian cancer have been conducted, and results have been largely inconsistent. Two recent studies found significant increased risk with frequent dairy consumption and perhaps with high intakes of calcium or lactose. The authors investigated the association between these foods and nutrients and ovarian cancer risk among 31,925 subjects in the Breast Cancer Detection Demonstration Project follow-up cohort. Multivariable (MV) relative risks (RRs) adjusted for age, parity, and other factors were estimated using Cox proportional hazards models. Over an average follow-up of 8.3 yr, 146 incident ovarian cancer cases were confirmed. Higher intakes of total dairy food (comparing four or more servings per day vs. less than one serving per day) were associated with a statistically significant decreased risk of ovarian cancer, although the trend was not significant (MV RR = 0.42; 95% confidence interval (CI) = 0.20-0.89; P for trend = 0.07). Comparing extreme quartiles, we observed a statistically nonsignificant inverse association between high dietary calcium intake and ovarian cancer (RR = 0.67; 95% CI = 0.43, 1.04; P for trend = 0.08). No statistically significant relations were found for consumption of specific dairy foods, lactose, or vitamin D and ovarian cancer risk. The possibility of a decreased risk of ovarian cancer for dietary calcium merits further evaluation.

Pathophysiology of impaired ovarian function in galactosaemia

Classical galactosaemia is an inherited inborn error of the major galactose assimilation pathway, caused by galactose-1-phosphate uridyltransferase (GALT) deficiency. Many GALT mutations have been described, with different clinical consequences. In severe forms, newborns present with a life-threatening, acute toxic syndrome that rapidly regresses under a galactose-restricted diet. However, long-term complications, particularly cognitive and motor abnormalities, as well as hypergonadotrophic hypogonadism in female patients are still unavoidable. The pathogenesis of galactose-induced ovarian toxicity remains unclear but probably involves galactose itself and its metabolites such as galactitol and UDP-galactose. Possible mechanisms of ovarian damage include direct toxicity of galactose and metabolites, deficient galactosylation of glycoproteins and glycolipids, oxidative stress and activation of apoptosis. As there is no aetiological treatment, clinical management of ovarian failure in galactosaemic patients principally relies on hormonal replacement therapy to induce pubertal development and to prevent bone loss and other consequences of estrogen deprivation. Further investigations will be necessary to better understand the metabolic flux of galactose through its biochemical pathways and the mechanisms of these secondary complications. The aim of this article is to present an extensive review on the pathogenesis and clinical management of galactose-induced premature ovarian failure.

Screening of the galactose-1-phosphate uridyltransferase gene in Indian women with ovarian failure

The present study was aimed at mutational screening of the gene coding for galactose-1-phosphate uridyltransferase in females with premature ovarian failure within an Indian population. A case-control-based study approach was used. It included females with premature ovarian failure (n = 108), primary amenorrhoea (n = 37) and secondary amenorrhoea (n = 9), and a control group of 136 women with a normal ovarian pattern. Gene sequencing analysis for the presence of mutations in the promoter and the coding regions of GALT has shown the absence of any mutation. A hexanucleotide deletion was found in the third intronic region of GALT in both cases and controls. These data support the hypothesis that there is no significant association between GALT mutations and ovarian failure, and hence the present authors conclude that there is no relationship between ovarian failure and GALT polymorphisms in Indian women.

Dietary galactose inhibits GDF-9 mediated follicular development in the rat ovary

Clinical evidence suggests an association between galactosemia and premature ovarian failure, but the mechanism is still not fully understood. Growth differentiation factor-9 (GDF-9) is thought to be an obligatory growth factor during the gonadotropin-independent phase of folliculogenesis. The objective of this study was to examine the effects of galactose on initiation of folliculogenesis in the peripubertal interval and the connection between galactose toxicity and GDF-9 expression in the ovary. After immature Long-Evans rats (n = 10) were fed a diet consisting of 20% galactose for 19 days, whole body, ovary and uterine weights were measured. Serum estradiol and progesterone concentrations were measured by radioimmunoassay. Ovarian follicles were counted by morphometric analysis and GDF-9 expression was investigated by immunohistochemistry and immunoblot assay. Galactose treatment did not affect the onset of puberty as marked by the time of vaginal opening. The galactose diet significantly decreased the number of healthy growing follicles. The results of immunoblot assay showed that both bands corresponding to propeptide and mature forms of GDF-9 decreased with the galactose diet about 90 and 70%, respectively. The results of immunohistochemical staining showed that the GDF-9 positive follicle number and the ratio of GDF-9 positive to GDF negative (primordial/non-growing) follicles significantly decreased with this high galactose diet. The present study suggests that a high galactose diet inhibits follicular development, possibly through down-regulation of GDF-9 in the rat ovary, implying that GDF-9 may be involved in galactose-related ovarian toxicity.

Intracellular galactose-1-phosphate accumulation leads to environmental stress response in yeast model

In humans, deficiency of galactose-1-phosphate uridyltransferase (GALT) can lead a metabolic disorder Classic Galactosemia. Although the biochemical abnormalities associated with this disease have been described in detail, few attempts have been made to characterize the pathogenic mechanisms of this disorder at the molecular level. Here we report the use of high-throughput DNA microarray to examine how galactose affects gene expression in isogenic yeast models that are deficient in either galactokinase (GALK) or GALT, two enzymes which are essential for normal galactose metabolism. We confirmed that the growth of our GALT-deficient, but not GALK-deficient yeast strain ceased 4 h after challenge with 0.2% galactose. Such inhibition was not associated with a reduction of ATP content and was reversible after removal of galactose from medium. We compared the gene expression profiles of the GALT-deficient and GALK-deficient cells in the presence/absence of galactose. We revealed that in the absence of galactose challenge, a subset of genes involved in RNA metabolism was expressed at a level 3-fold lower in the GALT-deficient cells. Upon galactose challenge, significantly more genes involved in various aspects of RNA metabolism and almost all ribosomal protein genes were downregulated in the GALT-deficient, but not GALK-deficient cells. Remarkably, genes involved in inositol biosynthesis and turnover were exclusively induced at high level in the galactose-intoxicated GALT-deficient cells. Our data thus suggested that RNA metabolism, ribosome biogenesis, and inositol metabolism were likely targets for galactose-1-phosphate, a toxic intermediate that is uniquely accumulated under GALT-deficiency.

Lactase persistence and ovarian carcinoma risk in Finland, Poland and Sweden

Ovarian carcinoma is the fourth most common cause of cancer death in women. The cause and pathogenesis of this disease has remained obscure. Galactose, the hydrolyzing product of the milk sugar lactose, has been hypothesized to be toxic to ovarian epithelial cells and consumption of dairy products and lactase persistence has been suggested to be a risk factor for ovarian carcinoma. In adults, downregulation of lactase depends on a variant C/T-13910 at the 5' end of the lactase gene. To explore whether lactase persistence is related to the risk of ovarian carcinoma we determined the C/T-13910 genotype in a cohort of 782 women with ovarian carcinoma. The C/T-13910 genotype was defined by solid phase minisequencing from 327 Finnish, 303 Polish, 152 Swedish patients and 938 Finnish, 296 Polish and 97 Swedish healthy individuals served as controls. Lactase persistence did not associate significantly with increased risk for ovarian carcinoma in the Finnish (odds ratio [OR]=0.77, 95% confidence interval [CI]=0.57-1.05, p=0.097), in the Polish (OR=0.95, 95% CI=0.68-1.33, p=0.75), or in the Swedish populations (OR=1.63, 95% CI=0.65-4.08, p=0.29). Our results do not support the hypothesis that lactase persistence increases the ovarian carcinoma risk. On the contrary, lactase persistence may decrease the ovarian carcinoma risk at least in the Finnish population.

Milk/dairy products consumption, galactose metabolism and ovarian cancer: meta-analysis of epidemiological studies

Ovarian cancer is the fifth most common cause of cancer death among women and the leading cause of gynaecological cancer death in the United States. Milk/dairy products consumption was considered to be a risk factor for ovarian cancer mainly because milk carbohydrate-lactose and galactose metabolism is toxic to oocytes. However, recent evidence does not support this hypothesis completely. We collected epidemiological studies related to the association between milk/dairy products consumption or galactose metabolism (lactose, galactose, galactose-1-phosphate uridyltransferase, lactose/transferase) and ovarian cancer published between January 1966 and August 2003 and found 27 items from 22 independent studies. Twenty studies were case-control studies and the other two were cohort studies. A meta-analysis method was conducted to estimate relative risk combining all relative data. In general, we did not find any association between milk/dairy products or galactose metabolism and ovarian cancer risk in this meta-analysis. The consumption of whole milk and butter, which contain relatively high amounts of fat, was positively (relative risk > 1.2), but not significantly, associated with an increased risk.

Carbofuran induced block of compensatory ovarian growth in hemicastrated albino mice

Carbofuran, a systemic N-methyl carbamate pesticide was orally administered at doses of 0.4, 0.7, 1 and 1.3 mg/(kg day) to normal hemicastrated (HC) mice for 15 consecutive days to investigate the effects on compensatory ovarian growth. Sham-operated and hemicastrated control mice were administered a similar quantity of olive oil. The vaginal smear and body weight of the mice were recorded daily and mice were sacrificed on day 16. The results revealed that the HC control mice showed 54.58% increase in the ovary weight of the remaining left ovary and many follicles, corpora lutea and showed normal estrous cycle as compared to Sham-operated control mice. The remaining left ovaries of the mice treated with 1.3 mg carbofuran showed 0.82% increase in the ovary weight and significant decrease in the number of developing follicles, corpora lutea, increase in many atretic follicles, the estrous cycle and its phases were affected when compared to HC control mice. In HC mice treated with 1 mg/(kg day) carbofuran resulted in 12.63% increase in the ovary weight and showed significant decrease in follicles, corpora lutea and many increased atretic follicles. The estrous cycle was affected with significant decrease in estrus phase and increase in diestrus phase. In HC mice treated with 0.7 mg/(kg day) carbofuran showed 26.30% increase in ovary weight and showed normal number of follicles and the mice showed normal number of estrous cycles but the estrus and diestrus phases were affected significantly. However, HC mice treated with 0.4 mg/(kg day) carbofuran revealed 33.09% increase in the ovary weight with no significant change in the follicles and estrous cycle as compared with that of HC control mice. There was no significant change in the body weight gain and weight of the organs such as uterus, kidney, adrenals, liver, spleen, thymus and thyroid in all the carbofuran treated mice. These observed effects of carbofuran on ovary, follicles and estrous cycle are considered to be hormonal imbalance.

Endometriosis-Associated Ovarian Cancer: A Clinicopathologic Review

Endometriosis is a common clinical disorder in women and usually presents with pelvic pain, infertility, or adnexal masses secondary to intracystic hemorrhage with the formation of an endometrioma. Endometriosis shares certain characteristics with malignant neoplasms, and malignant ovarian tumours have been documented in women with endometriosis. Endometriosis-associated ovarian cancer (EAOC) usually occurs in younger women, has favourable outcomes, and appears as either a low-grade tumour of endometrioid cell type or as a clear cell tumour. As it has been suggested that the pathologic features of "atypical endometriosis" may constitute a precancerous state, women with atypical endometriosis may be at an increased risk of developing EAOC. There are no prospective randomized trials assessing treatment regimens for EAOC. Most women receive treatment similar to other epithelial ovarian cancers. However, women with EAOC represent a subgroup of patients that may require different therapeutic options. English-language journals indexed in MEDLINE and PubMed were searched for relevant articles that evaluated the association between endometriosis and ovarian cancer, theories of pathogenesis and transformation, the clinical presentation and pathologic features of EAOC, as well as the treatment options available.

Temporal effect of carbofuran on estrous cycle compensatory ovarian hypertrophy and follicles in hemiovariectomized albino mice

Carbofuran, a systemic N-methyl carbamate pesticide was administered orally with an effective dose of 1.3mg/kg per day to hemiovariectomized (HOVX) mice for 5, 10, and 15 days. Sham-operated and HOVX control mice were administered a similar quantity of olive oil. The vaginal smear and body weight of the mice were recorded daily and mice were sacrificed on day 16. The results of the present study indicate that there is a significant decrease in the duration of the estrus with a concomitant significant increase in the duration of the diestrus with carbofuran treatment for 10 days. In the HOVX mice treated with carbofuran for 15 days there was a significant decrease in the length of the estrous cycle and the duration of the estrus and metestrus with a concomitant significant increase in the diestrus. There was a significant increase in the ovarian weight in HOVX control mice when compared to that of the sham operated control mice. HOVX mice treated with carbofuran for 10 and 15 days showed a significant decrease in the relative ovarian weight with a concomitant inhibition of compensatory ovarian hypertrophy in HOVX mice. There was also a significant decrease in the ovarian growth rate in relation to the contralateral ovary of the same animal. There was a significant decrease in the number of small and total number of healthy follicles with a concomitant significant increase in the number of medium, large and total number of atretic follicles in HOVX mice treated with carbofuran for 10 days. There was a significant decrease in the number of small, medium, large, and total number of healthy follicles with a concomitant significant increase in the number of medium, large, and total number of atretic follicles in HOVX mice treated with carbofuran for 15 days. The administration of carbofuran in the present study showed that there is no significant change in the body and organs weight such as uterus, kidney, adrenals, liver, spleen, thymus and thyroid in all the carbofuran-treated mice. The above findings such as disruption in the estrous cycle, inhibition of compensatory ovarian hypertrophy, and follicular toxicity may be due to a direct effect on the ovary or through the hypothalamo-hypophysial-ovarian axis.

A prospective study of dietary lactose and ovarian cancer

The milk sugar lactose is an hypothesized risk factor for epithelial ovarian cancer because of possible direct toxic effects of its metabolites on oocytes or by compensatory gonadotropin stimulation. Women are presently encouraged to consume dairy products as a source of calcium to prevent osteoporosis. The objective of our study was to prospectively assess lactose, milk and milk product consumption in relation to ovarian cancer risk among 80326 participants in the Nurses' Health Study who had no history of cancer other than nonmelanoma skin cancer. Participants in the Nurses' Health Study reported on known and suspected ovarian cancer risk factors in questionnaires mailed biennially from 1976 to 1996. Food frequency questionnaires were included in the years 1980, 1984, 1986 and 1990. Newly reported ovarian cancer was documented by review of medical records. During 16 years of follow-up (1980-1996), 301 cases of invasive epithelial ovarian cancer were confirmed. Pooled logistic regression was used to control for age, body mass index (kg/m(2)), caffeine intake, oral contraceptive use, smoking history, parity and tubal ligation. For all subtypes of invasive ovarian cancer combined, we observed a nonsignificant 40% greater risk for women in the highest category of lactose consumption compared to the lowest (multivariate relative risk (RR) 1.40, 95% confidence interval (CI), 0.98-2.01). We observed a 2-fold higher risk of the serous ovarian cancer subtype among those in the highest category of lactose consumption compared to the lowest (RR 2.07, 95% CI, 1.27-3.40). For each 11-gram increase in lactose consumption (the approximate amount in one glass of milk), we observed a 20% increase in risk of serous cancers (RR 1.20, 95% CI, 1.04-1.39). Skim and low-fat milk were the largest contributors to dietary lactose. Women who consumed one or more servings of skim or low-fat milk daily had a 32% higher risk of any ovarian cancer (RR 1.32, 95% CI, 0.97-1.82) and a 69% higher risk of serous ovarian cancer (RR 1.69, 95% CI, 1.12-2.56) compared to women consuming 3 or less servings monthly. Controlling for fat intake did not change our findings. Our findings provide some support for the hypothesis that lactose intake increases risk of epithelial ovarian cancer. However, the observed excess risk appeared limited to the serous subtype of ovarian cancer in our study.

Effect of maternal overnutrition during pregnancy on pituitary gonadotrophin gene expression and gonadal morphology in female and male foetal sheep at day 103 of gestation

The aim was to determine whether nutritionally mediated restriction of placental growth alters foetal body growth, pituitary gonadotrophin gene expression and gonadal development at Day 103 of gestation. Embryos recovered from adult ewes inseminated by a single sire were transferred, singly, into the uteri of adolescent recipients. After transfer, adolescent ewes were offered a high (H, n=16) or moderate (M, n=12) level of a complete diet. Ewes were slaughtered at 103+/-0.2 days of gestation and foetal blood, brain, pituitary and gonads were collected. Mean placental weight was lower (P< 0.01) in H than in M groups but foetal weight and reproductive organ weights were similar. Maternal nutrition did not influence LHbeta or FSHbeta mRNA expression in either sex but FSHbeta mRNA expression was higher (P< 0.001) in female (n=11) than in male (n=17) foetal pituitaries. Mean foetal plasma gonadotrophin concentrations were not influenced by dietary intake in either sex. Plasma progesterone concentrations were lower (P=0.001) in foetuses derived from H compared with M intake dams. Compared with M foetuses (n=5), ovaries from H foetuses (n=6) had fewer primordial follicles (P< 0.05) and fewer follicles in total (P< 0.005). In contrast, maternal nutritional status did not influence either seminiferous cord or Sertoli cell numbers in male foetuses (H, n=10; M, n=7). It is concluded that high maternal nutrient intakes restricted placental growth and altered foetal ovarian follicular development prior to the end of the second third of gestation. The latter effect was independent of gonadotrophin secretion.Crown

Premature ovarian failure (POF): discordance between somatic and reproductive aging

Premature ovarian failure (POF) is a unique example of isolated organ senescence, with a population prevalence of approximately 1%. Though the phenotypic expression of POF is similar to that of age-appropriate natural menopause, the underlying pathophysiological mechanisms are diverse and not entirely clear. The impact of POF on the patient is profound, with myriad ramifications, ranging from psychological devastation to multi-system implications of estrogen deprivation and its sequelae. The hastening of degenerative changes noted in these patients however, are not entirely ameliorated with estrogen replacement and POF may indeed represent an acceleration of the aging process.