Endocrine disruptors: new players in the pathophysiology of type 2 diabetes?

The prevalence of type 2 diabetes (T2D) has dramatically increased worldwide during the last few decades. While lifestyle factors, such as decreased physical activity and energy-dense diets, together with genetic predisposition, are well-known actors in the pathophysiology of T2D, there is accumulating evidence suggesting that the increased presence of endocrine-disrupting chemicals (EDCs) in the environment, such as bisphenol A, phthalates and persistent organic pollutants, may also explain an important part in the incidence of metabolic diseases (the metabolic syndrome, obesity and T2D). EDCs are found in everyday products (including plastic bottles, metal cans, toys, cosmetics and pesticides) and used in the manufacture of food. They interfere with the synthesis, secretion, transport, activity and elimination of natural hormones. Such interferences can block or mimic hormone actions and thus induce a wide range of adverse effects (developmental, reproductive, neurological, cardiovascular, metabolic and immune). In this review, both in vivo and in vitro experimental data and epidemiological evidence to support an association between EDC exposure and the induction of insulin resistance and/or disruption of pancreatic ß-cell function are summarized, while the epidemiological links with disorders of glucose homoeostasis are also discussed.

Iodine status has no impact on thyroid function in early healthy pregnancy.

Aim. To assess the impact of iodine status in early pregnancy on thyroid function. Methods. Women >18 years old seen at their first prenatal consult before 12 weeks of amenorrhea and without personal thyroid history were proposed thyroid screening and were eligible if they had strictly normal thyroid tests (fT4 > 10th percentile, TSH < 2.5 mUI/L, negative anti-TPO antibodies). Evaluation included thyroid ultrasound, extensive thyroid tests, and ioduria (UIE). Results. 110 women (27.5 y, 8 weeks of amenorrhea, smoking status: 28% current smokers) were enrolled. Results are expressed as medians. UIE was 116 µg/L. 66.3% of women had iodine deficiency (ID) defined as UIE < 150. FT4 was 14.35 pmol/L; TSH 1.18 mUI/L; fT3 5 pmol/L; thyroglobulin 17.4 ng/mL; rT3 0.27 ng/mL; thyroid volume: 9.4 ml. UIE did not correlate with any thyroid tests, but correlated negatively with thyroid volume. UIE and all thyroid tests, except fT3, correlated strongly with ßhCG. Smoking correlated with higher thyroid volume and thyroglobulin and with lower rT3. Conclusions. In pregnant women selected for normal thyroid function, mild ID is present in 66% during the 1st trimester. The absence of correlation between UIE and thyroid tests at that stage contrasts with the impact of ßhCG and, to a lesser degree, maternal smoking.

Imbalance of MMP-2 and MMP-9 expression versus TIMP-1 and TIMP-2 reflects increased invasiveness of human testicular germ cell tumours.

The histological classification of testicular germ cell tumours (TGCTs) to seminoma or non-seminomatous germ cell tumours is at present the main criterion for the clinical outcome and selection of the treatment strategy. In view of the need to identify novel prognostic biomarkers for TGCTs, we investigated the expression of the matrix metalloproteinases MMP-2 and MMP-9 in testicular tumour tissues and cell lines of both seminoma and non-seminoma origin. Immunohistochemistry and zymography analysis of tumoural tissues showed significantly higher levels of MMP-2 and MMP-9 compared with normal testis with the active forms detected only in the tumour tissues. Three cell lines representative of the different tumour types, JKT-1 seminoma, NCCIT teratocarcinoma and NTERA2/D1 embryonal carcinoma were also evaluated for their expression of these MMPs using qPCR and zymography and for their invasive properties. The more invasive non-seminomatous teratocarcinoma and embryonal cells expressed considerably more MMP-2 and MMP-9 compared with seminoma cells exhibiting lower invasiveness. Furthermore, an inverse relation was observed between invasiveness and the expression of endogenous inhibitors TIMP-1 and TIMP-2. The MMP inhibitor Marimastat inhibited invasion in all cell lines, the highest inhibition was observed in the more invasive NTERA2/D1 and NCCIT cells, which presented the highest ratio of MMP-2 and MMP-9 vs. TIMP-1 and TIMP-2. These results highlight the importance of MMP-2 and MMP-9 in the invasiveness of testicular tumours and suggest that their levels, vs. those of TIMP-1 and TIMP-2, may represent potential biomarkers for testicular malignancy.

Vascular placental abnormalities and newborn death in a pregnant diabetic woman with familial partial lipodystrophy type 3: a possible role for peroxisome proliferator-activated receptor γ.

The peroxisome proliferator-activated receptor protein gamma (PPARγ), a nuclear receptor involved in adipocyte differentiation, energy homoeostasis and fat storage, can lead, in rare cases of coding mutations, to familial partial lipodystrophy type 3 (FPLD3) with severe insulin resistance. PPARγ is also highly expressed in the syncytiotrophoblast and extravillous cytotrophoblast cells. It has a key role in trophoblast invasion, as shown by studies in vitro, but its precise role during placentation remains to be elucidated, and fetomaternal outcomes of FPLD3 pregnancies also need to be assessed. This report is of a novel missense heterozygous mutation of PPARγ identified during pregnancy in a young diabetic woman who, at 3weeks of amenorrhoea, prematurely delivered a baby who died 24 h later. Histopathological analysis revealed important vascular placental abnormalities. The presence of the PPARγ mutation in placental tissues in the absence of fetal malformations and maternal hypertension suggests that FPLP3 pregnancies may be at high-risk, especially if the fetus has inherited the mutation. It also supports a physiological role for PPARγ during placentation.

[Post-menopausal ovarian hyperthecosis]. / Hyperthécose ovarienne post-ménopausique.

Ovarian hyperthecosis is infrequent but it represents the first cause of post-menopausal hyperandrogenia. Pathophysiology of ovarian hyperthecosis remains poorly understood but the metabolic syndrome observed in most patients suggests that insulin resistance associated with high, postmenopausal LH levels, might play a role as in polycystic ovarian syndrome. We report here four patients who presented post-menopausal hyperandrogenia. Although high, tumoral, plasma testosterone levels, lack of focused radiological lesions except enlarged ovaries, associated to the metabolic syndrome, suggested ovarian hyperthecosis. Bilateral annexectomy allowed histological confirmation of hyperthecosis showing specific luteinized stromal cells and led to the complete suppression of the inappropriate androgen secretion.

Unconjugated bisphenol A cord blood levels in boys with descended or undescended testes.

BACKGROUND: Human toxicity of bisphenol A (BPA), a weak estrogenic environmental endocrine disrupting compound, widely used in plastics, baby bottles, cans and dental sealants, is under investigation. Fetal or perinatal exposure in rodents is associated with programmed adult reproductive diseases. Human epidemiological studies remain scarce, especially concerning testicular development. We have investigated the relationship between fetal exposure to BPA and cryptorchidism. METHODS: Using a radioimmunoassay performed after extraction, validated by high-performance liquid chromatography and mass spectrometry, active levels of unconjugated BPA (uBPA) in cord blood (CB) were measured in 152 boys born after 34 weeks gestation, with cryptorchid or descended testes. RESULTS: Active uBPA was detectable in all CB samples, with values in the control group (n = 106) of 0.14-4.76 ng/ml, median: 0.9 ng/ml; mean ± SD: 1.12 ng/ml ± 0.86 ng/ml, which did not differ from cryptorchid boys (n = 46, 1.26 ± 1.13 ng/ml, P = 0.38). uBPA in controls correlated with CB inhibin B (P < 0.01) and total testosterone (P < 0.05), and with maternal milk polychlorinated bisphenyl 138 (P < 0.03). uBPA did not correlate with clinical maternal or fetal parameters or with other steroid or polypeptide CB hormones assessed. CONCLUSIONS: The presence of uBPA in all CB samples suggests placental transfer and fetal exposure. Similar uBPA levels in the control and cryptorchid groups make the participation of fetal exposure to uBPA in the physiopathology of undescended testes unlikely. However, the observed nanomolar uBPA concentrations support assessment of epidemiological relationships between CB uBPA and other human diseases.

Prospective study on the prevalence and associated risk factors of cryptorchidism in 6246 newborn boys from Nice area, France.

To assess the incidence and risk factors of cryptorchidism in Nice area. A 3-year prospective study was conducted at two maternity wards involving neonatal screening of boys born ≥34weeks of amenorrhoea. Methodology was strict with examination at birth, 3 and 12months by the same paediatrician. Two strictly matched controls were included for each case. Information on child and parents (medical history, pregnancy, lifestyle) was recorded using medical chart and self-administered questionnaires. A total of 102 of 6246 boys were born with cryptorchidism (prevalence 1.6%, 95 included). Half of them were still cryptorchid at three and 12months with, however, 10% of secondary re-ascent (recurrent cryptorchidism) at 12months, justifying long-term follow-up. Cryptorchidism at birth was associated with instrumental delivery, inguinal hernia and urogenital malformations, particularly micropenis and paternal history of cryptorchidism. Our results suggest that maternal exposure to anti-rust or phthalates could be a risk factor, whereas eating fruits daily seemed somewhat protective. Prevalence of cryptorchidism in our area is on the lower bracket compared with other countries, and is associated with both familial and environmental risk factors.

Universal two-step screening strategy for gestational diabetes has weak relevance in French Mediterranean women: should we simplify the screening strategy for gestational diabetes in France?

AIM: Currently, there is no international consensus for gestational diabetes mellitus (GDM) diagnosis. This is a report of our experience of GDM screening according to the 1996 French guidelines. METHODS: For 5 years, all pregnant women followed at our hospital (n=11,545) were prospectively screened for GDM between weeks 24 and 28 of pregnancy with a two-step strategy: the O'Sullivan test (OS) with a threshold at 130 mg/dL, followed by a 100-g OGTT if positive. GDM was diagnosed according to Carpenter and Coustan criteria. RESULTS: Prevalence of GDM was 4.26% [344/1451 of patients with an OS of 130-199 mg/dL (12.1%); and 148 patients with an OS greater than 200 mg/dL]. The false-positive rate for the OS was 76.8%. Compared with 140 mg/dL, a threshold of 130 mg/dL caused 401 additional negative OGTTs in 90% of cases. In 80.7% GDM patients, fasting glucose was less than 95 mg/dL. The time lag between OS and OGTT was 3 weeks (1-84 days). Risk factors associated with GDM were maternal age, preconception overweight and obesity, parity, personal history of GDM or macrosomia, and familial history of obesity (P<0.05), but not diabetes. Also, 20% of GDM patients had no risk factors, whereas they were present in 75% of patients without GDM. CONCLUSION: In our population, a two-step screening strategy for GDM was neither relevant nor efficient. It could be simplified with a single-step definitive screening strategy using a 75-g OGTT, as used in the HAPO study, and as recommended by the IADPSG and the recent French Expert Consensus. At present, there are still no evidence-based arguments to help in deciding between selective or universal screening for GDM.

[Is there any medical treatment to preserve fertility during chemotherapy in women?]. / Existe-t-il des médicaments fertiloprotecteurs en cas de chimiothérapie chez la femme ?

Intensive use of radio-chemotherapy has greatly improved the prognosis associated with cancer in young girl or women patients. However, improvement of the vital prognosis is frequently associated with impairment of fertility and premature ovarian failure. In vitro fertilization (IVF) followed by embryo cryopreservation is an available method, which needs a partner and a pretreatment stimulation. Ovarian and oocyte cryopreservation are techniques showing great promise. However, the nec plus ultra would be to be able to protect ovaries during chemotherapy. Since more than 10 years Gonadotropin releasing hormone (GnRH) analogues have been investigated as possible means to preserve fertility in young women. However, even recent prospective, randomized studies do not demonstrate clearly their effectiveness. To prevent primordial follicle apoptosis, an inhibitor of tysosine kinase, imatinib, has recently been proposed and positively evaluated in mice. It could represent an interesting hope to preserve female fertility during chemotherapy.

Klinefelter's syndrome and bone mineral density: is osteoporosis a constant feature?

OBJECTIVES: Data on bone mineral density (BMD) in Klinefelter syndrome (KS) are scarce and contradictory. The aim of the present study was to investigate BMD in patients with KS and in healthy controls with special attention to gonadal status. MATERIAL AND METHODS: We investigated 26 patients with KS (30±9 yr) who had never been treated with testosterone. Thirty-nine age-matched healthy males served as controls. We assessed BMD by performing dual energy X-ray absorptiometry and measured serum hormone levels, including total testosterone (T), free testosterone, estradiol (E2), leptin. The estrogen to androgen ratio (E2/T) was used as an indirect measure for aromatase activity. RESULTS: No difference was found in BMD at femoral neck (1.06 ± 0.16 vs 1.04 ± 0.14 g/cm²), or at lumbar spine (1.00 ± 0.09 vs 1.03 ± 0.11) between patients and controls. Two patients and one control were classified as osteoporotic (T-score ≤ -2.5). Compared with controls, patients had lower levels of T and free testosterone, similar E2 levels, and increased E2/T (P < 0.05). In KS patients, leptin was significantly higher and correlated positively with E2/T (r = 0.484, P = 0.02). E2/T correlated with femoral neck BMD (r = 0.566, p = 0.02), T and free T correlated with lumbar spine BMD (r = 0.433, P = 0.05 and r = 0.534, P = 0.05). CONCLUSION: Osteoporosis is not a constant feature in young patients with KS, even without testosterone substitution. The aromatisation of T into E2, related to adiposity, may contribute to the achievement and maintenance of normal BMD in some KS patients.

Lethal acute demyelinization with encephalo-myelitis as a complication of cured Cushing's disease.

Cushing's disease is usually associated with higher mortality rate, especially from cardiovascular causes. Development or exacerbation of autoimmune or inflammatory diseases is known to occur in patients with hypercortisolism after cure. We report for the first time a 34-year old woman with a psychiatric background, who developed four months after the surgical cure of Cushing's disease an acute disseminated encephalomyelitis (ADEM) presenting initially as a psychiatric illness. We hypothesize that the recent correction of hypercortisolism triggered ADEM and that the atypical presentation, responsible for diagnosis delay, led to the death of this patient.

RET gene mutations are not involved in the origin of human testicular seminoma.

Testicular germ cell cancers are the most common solid malignancies in young men, but their pathogenesis remains undetermined although some epidemiological data have implicated both environmental and genetic factors. Glial cell-derived neurotrophic factor (GDNF) is secreted by Sertoli cells, and promotes germ stem cell proliferation by activating RET, a tyrosine kinase receptor. Over-expression of GDNF in adult transgenic mice induces the development of testicular tumours that mimic human seminoma, the most frequent testicular germ cell tumour. Activating mutations of RET were previously reported in several types of cancer, including thyroid, pituitary, adrenal and melanoma cancer. Both mouse experimental model and clinical studies suggested that mutations or selective polymorphisms of RET might be associated with human seminoma. To verify this hypothesis, we conducted this study in a French University Hospital and carried out an association study using tissue samples from 66 paraffin-embedded seminoma tumours. The most frequently mutated exons of the RET proto-oncogene were sequenced to identify mutations or selective polymorphisms. No somatic mutations were identified. The polymorphic variants frequencies did not differ from those in a control Caucasian population. Human classical seminoma that occurs in young men does not appear to be linked with mutations or relevant polymorphisms of RET.

Adrenocortical incidentaloma with uncertain prognosis associated with an inadequately treated congenital adrenal hyperplasia.

Large adrenal tumors are rarely associated with adrenal enzymatic deficiency, except in 11-ss-hydroxylase insufficiency. These tumors are exceptionally malignant. We report here the case of a patient with a congenital 21-hydroxylase deficiency (compound heterozygote for two severe mutations in the CYP21A2 gene) untreated for 20 years. His evaluation at 36 years of age showed a four-centimeter mass in the left adrenal gland, with most characteristics suggestive of malignancy (CT and positron emission tomography [PET] scan). We performed a surgical resection that established the diagnosis of adrenocortical tumor of uncertain prognosis (Weiss's score: 3). Even though malignant tumors are unusual in adrenal deficiency, our observation shows the need for a replacement therapy during adulthood, with a regular CT scan follow up in order to diagnose early isolated adrenal adenoma and remove it in case of malignancy suspicion.

[Iodine status and thyroid function of 330 pregnant women from Nice area assessed during the second part of pregnancy]. / Statut iodé et fonction thyroïdienne chez 330 femmes de la région niçoise évaluées en deuxième partie de grossesse.

BACKGROUND: Iodine deficiency (ID) is still common in Western Europe and its prevention remains a challenge, particularly during pregnancy. METHODS: We studied 330 pregnant women in the third trimester of pregnancy for ioduria (UIE) and thyroid tests (TSH, fT4). We collected information on personal history of thyroid disease and treatment with thyroid hormones or iodinated pregnancy tablets. RESULTS AND DISCUSSION: Median UIE was 64 microg/l, reflecting inadequate iodine intake in our population. According to the UIE threshold used for diagnosis (100 to 150 microg/l), ID was present in 74.3% to 85.8% of women; 5.4% had excessive iodine intake, including one taking iodine fortified tablets. Only 8.8% had adequate intake, suggesting that current strategies to eradicate ID are inefficient in our country. Among the 22 women taking iodine supplements, only three had adequate UIE and four had UIE below the detection level, which could suggest either poor compliance or insufficient supplementation. Median fT4 was 12.3pmol/l (8-20.1) and TSH 1.93mUI/l (0.24-6.57). We used different thresholds proposed in the literature to diagnose: hypothyroxinemia: 41.2% were less than 12pmol/l, 10% less than 10.3pmol/l and 1.8% less than 9pmol/l (lower limit of our reference range); subclinical hypothyroidism: 26.3% had TSH greater than 2.5 or 3.9% greater than 4mUI/L, 1.2 to 13% had combined low fT4 (<9pmol/l or <12pmol/) and higher TSH (>2.5mUI/l). There was no correlation between UIE and thyroid tests, nor maternal predicting factors for ID. CONCLUSION: ID is common in our population. The wide range of hypothyroxinemia and subclinical hypothyroidism prevalence should also trigger reflection of diagnostic thresholds and therapeutic intervention.

[Oocyte donation in patients with Turner syndrome: A high-risk pregnancy]. / Procréation par don d'ovocytes dans le syndrome de Turner : une situation à haut risque.

Turner's syndrome is characterized by an ovarian failure, which occurs in most cases before puberty and leads to infertility. In vitro fertilization with oocyte donation has dramatically transformed the prognosis of infertility of these women. However, in the same time, it has become obvious that pregnancies in Turner's syndrome are at very high risk of possible sudden death because of a specific risk for cardiovascular complications involving aortic root dissection. We report the case of a serious cardiac failure occurred during a twin pregnancy obtained by oocyte donation in a 39-year-old patient with Turner's syndrome. Pregnancy outcome was hopefully favourable thanks to a foetal extraction at 27 weeks of amenorrhoea. If the most reported cases of maternal deaths in patients with Turner's syndrome are associated with an aortic root dissection, our observation is characterized by a full normal cardiologic assessment before the pregnancy and by the absence of aortic root dilatation during pregnancy. This case also illustrates the very high risk of pregnancy in women with Turner's syndrome and the importance of a multidisciplinary care by professionals informed and been used to this obstetric practice.

[Environmental endocrine disruptors and breast cancer: new risk factors?]. / Perturbateurs endocriniens environnementaux et cancer du sein : de nouveaux facteurs de risque ?

Human epidemiological studies and experimental animal data strongly suggest that xenobiotics with estrogenic activity may participate in to the increasing incidence of breast cancer, the most frequent cancer all around the world. Several reports have since 15 years reported positive correlations between blood or peritumoral adipose tissue levels of persistent organic compounds including organochloride pesticides and breast cancer risk. Moreover, fetal or perinatal exposition to low doses of such endocrine disruptors induce premalignant or malignant transformation of adult mammary gland in rodents. However, this environmental endocrine disrupter hypothesis still needs to be demonstrated. Further human studies are needed which will consider the exposition window, the association of several xenoestrogens, the molecular mechanisms involved and the possible individual genetic susceptibility in order to identify pertinent biomarkers and to define acceptable environmental concentration levels for agricultural or industrial chemical new products to be used.

[Environmental pollutants in maternal milk and cryptorchidism]. / Polluants environnementaux dans le lait maternel et cryptorchidie.

OBJECTIVE: Numerous maternal lipophilic compounds are eliminated into milk during lactation, their concentrations reflecting fetal in utero exposure. Some of them are endocrine disruptors. Their role in the occurrence of genital malformation, dysfunction or cancer has been suggested. We wanted to study the exposure of our population and its potential association with cryptorchidism, as few clinical studies are available. PATIENTS AND METHODS: Over three years, we screened for cryptorchidism all boys born alive at or above 34 weeks of gestational age, in two maternity wards (CHU Nice, CHG Grasse). Cryptorchid boys were matched with two controls. Nursing mothers provided a colostrum sample that was screened for 15 compounds known for their antiandrogenic and/or anti estrogenic properties, including dichloro-diphenyl-trichloro-ethylene (DDE), polychlorinated biphenyls (PCBs), dibutylphthalate (DBP) (& metabolite monobutylphthalate-mBP) and hexachlorobenzene (HCB). RESULTS: Out of 6246 boys, 102 were cryptorchid (1.6%). All available colostrums (56 for cryptorchid and 69 for controls) were contaminated. Median concentrations of DDE, PCBs, HCB and phthalates were higher though not significantly in cryptorchid versus controls. Cryptorchid boys were more likely to be classified in the most contaminated groups for DDE and SigmaPCBs, with a trend for mBP. Odds ratio (OR) for cryptorchidism was increased for the highest score of SigmaPCB, with a trend only for DDE versus the lowest score of those components. Our results are similar to those of a Scandinavian study with comparable design. DISCUSSION AND CONCLUSIONS: Our results show the universal contamination of milk with endocrine disruptors in our area, and support the association between congenital cryptorchidism and fetal exposure to PCBs and possibly DDE, alone or in association with other chemicals.

Tumor necrosis factor-alpha -308 polymorphism in infertile men with altered sperm production or motility.

BACKGROUND: One of the most well-documented cytokines suspected as a hazard to male fertility is tumor necrosis factor-alpha (TNFalpha). Genetic factors such as single-nucleotide polymorphisms (SNPs) in the TNF gene cluster impact TNFalpha levels. Our objective was to establish the potential involvement of -308 TNF SNP in male infertility risk. METHODS: In 684 infertile male patients undergoing an intracytoplasmic sperm injection procedure, we used allele-specific polymerase chain reaction (PCR) and PCR-RFLP to investigate the distribution of the guanine (G)-to-adenosine (A) substitution at position -308 in the promoter region of the TNFalpha gene. RESULTS: An increased frequency of the -308 TNFalpha A allele was found in patients with low sperm count of testicular origin [P = 0.002; odds ratio (OR) = 2.93] or with normal production count but altered sperm motility (P = 0.003; OR = 2.32), compared with a patient group with normal sperm count and quality (morphology and motility). In patients with low sperm count exhibiting TNFalpha A allele, compared with those with G allele, an alteration in hormonal balance was observed with increased inhibin B levels and subsequent reduced FSH plasma levels, leading to an FSH/inhibin B ratio roughly half as high (from 0.07 +/- 0.01 in TNFA versus 0.13 +/- 0.02 in TNFG allele groups, P < 0.0001). CONCLUSION: As the -308 TNFalpha A allele has been associated with an increased expression/production of TNFalpha, the potential use of therapies based on inhibition of TNFalpha activities could represent possible therapeutic opportunities for patients with low sperm count (i.e. primary testicular dysfunction) or with altered sperm motility.