Biochemical Diagnosis of Adrenal Insufficiency: the Added Value of Dehydroepiandrosterone Sulfate Measurements

ObjectiveTo review biochemical tests used in establishing the challenging diagnosis of adrenal insufficiency.MethodsWe reviewed the relevant literature, including our own data, on various biochemical tests used to determine adrenal function. The advantages and limitations of each approach are discussed.ResultsBaseline measurements of serum cortisol are helpful only when they are very low (≤ 5 μg/dL) or clearly elevated, whereas baseline plasma adrenocorticotropic hormone levels are helpful only when primary adrenal insufficiency is suspected. Measurements of baseline serum dehydroepiandrosterone sulfate (DHEA-S) levels are valuable in patients suspected of having adrenal insufficiency. Although serum DHEA-S levels are low in patients with primary or central adrenal insufficiency, a low level of this steroid is not sufficient by itself for establishing the diagnosis. A normal age- and sex-adjusted serum DHEA-S level, however, practically rules out the diagnosis of adrenal insufficiency. Many patients require dynamic biochemical studies, such as the 1-μg cosyntropin test, to assess adrenal function.ConclusionIn establishing the diagnosis of central adrenal insufficiency, we recommend measurements of baseline serum cortisol and DHEA-S levels. In addition to these, determination of plasma levels of aldosterone, adrenocorticotropic hormone, and renin activity is necessary when primary adrenal insufficiency is suspected. With a random serum cortisol level of ≥ 12 μg/dL in the ambulatory setting or a normal age- and sex-adjusted DHEA-S level (or both), the diagnosis of adrenal insufficiency is extremely unlikely. When serum DHEA-S levels are low or equivocal, however, dynamic testing will be necessary to determine hypothalamic-pituitary-adrenal axis function. (Endocr Pract. 2011;17:261-270)     

Selective stimulation by cinnamaldehyde of progesterone secretion in human adrenal cells

AimsCinnamon bark has been used to treat menstrual pain and infertility. While several pharmacological studies have suggested anti-inflammatory properties, the mechanisms by which the herb exerts its various activities have not been well understood. Recent reports suggest menstrual distress is related to higher estradiol levels, higher estradiol/progesterone ratios. Cinnamaldehyde, a major active constituent of Cinnamomum cassia has been shown to stimulate cathecholamine release from adrenal glands. The objective of the present study is to examine whether cinnamaldehyde stimulates secretion of progesterone and other steroid hormones in human adrenal cells.Main methodsHuman adrenal cells, H295R were exposed for 24 h in a serum-free medium to various concentrations of cinnamaldehyde. Steroid hormones in the cultured medium were measured by a highly sensitive LC-electrospray ionization-tandem mass spectrometry.Key findingsExposure to cinnamaldehyde increased progesterone release in a dose-dependent manner. Testosterone and dehydroepiandrosterone concentrations decreased in the presence of cinnamaldehyde. The release of cortisol or estradiol was not affected by treatment with cinnamaldehyde. cAMP in the cultured medium was increased from 0.06 ± 0.0007 pmol/ml to 0.12 ± 0.0028 pmol/ml by exposure to cinnamaldehyde. The addition of isobutylmehtylxanthine, a phosphodiesterase inhibitor, caused a doubling of the amount of cAMP up to 0.397 ± 0.036 pmol/ml in the presence of cinnamaldehyde.SignificanceThese data suggest that cinnamaldehyde selectively induced progesterone production and inhibited production of testosterone and dehydroepiandrosterone in human adrenal cells.     

Diagnostic performance of salivary cortisol and serum osteocalcin measurements in patients with overt and subclinical Cushing's syndrome

ObjectiveThe cut-off value for salivary cortisol measurement for the diagnosis of Cushing's syndrome (CS) may depend both on the severity of the disease and the composition of control group. Therefore, we examined the utility of midnight salivary cortisol measurements in patients who were evaluated for signs and symptoms of CS or because they had adrenal incidentalomas. Because serum osteocalcin (OC) is considered as a sensitive marker of hypercortisolism, we also investigated whether OC could have a role in the diagnosis of CS.Patients and methodsEach of the 151 patients was included into one of the following groups: (A) overt CS (n = 23), (B) subclinical CS (n = 18), (C) inactive adrenal adenomas (n = 40), (D) patients without HPA disturbances (n = 70). Patients (C + D) were used as controls. Serum, salivary and urinary cortisol, and OC were measured by electrochemiluminescence immunoassay.ResultsGroup A had suppressed OC as compared to both group B and group (C + D). Serum and salivary cortisol concentrations showed strong negative correlations with OC in patients with overt CS. The areas under the curves of salivary and serum cortisol at 24:00 h (0.9790 and 0.9940, respectively) serum cortisol after low dose dexamethasone test (0.9930) and OC (0.9220) obtained from ROC aanalysis for the diagnosis of overt CS were not statistically different.ConclusionThis study confirms the usefulness of midnight salivary cortisol measurements in the diagnosis of overt CS in the everyday endocrinological praxis. Our results suggest that OC may have a role in the diagnosis of overt CS.     

Adenoma adrenal como etiología de síndrome de Cushing: veinte años de experiencia en un centro mexicano de tercer nivel

IntroductionCushing's syndrome (CS) includes a wide range of clinical and laboratory abnormalities and is the final outcome of chronic glucocorticoid exposure. Adrenal adenomas are an uncommon cause of adult CS.ObjectiveTo describe the characteristics and outcome of patients with CS caused by adrenal adenomas in a referral center.MethodsWe performed a retrospective cross-sectional observational study of patients with a diagnosis of CS caused by adrenal adenomas managed in our center over a 20-year period. Our clinical experience in the diagnosis and treatment of this entity was analyzed.ResultsThere were a total of 20 patients, 19 women and one man. The mean age was 25.9 years (14 to 52). The most frequently recorded clinical data were hirsutism and moon face. The mean morning cortisol level was 26.9±10.7 mcg/dl, the mean afternoon level was 24.4±8.5 mcg/dl and the mean corticotropin (ACTH) concentration was 24±19.4 pg/ml. Only four patients (20%) had ACTH levels below 5 pg/ml. The results of dynamic testing with dexamethasone suggested adrenal adenoma in 100% of the patients. Seventy percent of adenomas were found in the left gland. The mean size of the lesion was 2.8±0.47 cm.ConclusionsIn dynamic testing, the criteria of non-suppression with high doses of dexamethasone were evident in almost all patients. ACTH measurement in our center was not reliable in identifying adrenal adenoma as a cause of CS.     

Use of steroid profiles in determining the cause of adrenal insufficiency

HYPOTHESIS: A cortisol response to adrenocorticotropin injection is the standard test for diagnosing adrenal insufficiency. Multiple steroid hormones can now be accurately measured by tandem mass spectrometry in a single sample. The study objective was to determine whether a steroid profile, created by simultaneous measurement of 10 steroid hormones by tandem mass spectrometry, would help determine the cause of adrenal insufficiency. DESIGN: A 10-steroid profile was measured by tandem mass spectrometry during the performance of a standard high dose cortrosyn stimulation test. The steroids were measured at baseline, 30, and 60min following synthetic adrenocorticotropin injection. Adrenal insufficiency was defined as a peak cortisol level of less than 20microg/dL. Testing was conducted in the general clinical research center of a university medical center. Normal volunteers, patients suspected of having adrenal insufficiency, and patients with known adrenal insufficiency participated. RESULTS: Our results showed that adrenal insufficiency of any cause was adequately diagnosed using the response of 11-deoxycortisol, dehydroepiandrosterone, or these analytes combined in a two-steroid profile. A three-steroid profile yielded a test with 100% accuracy for discriminating primary adrenal insufficiency from normal status. Primary adrenal insufficiency was well separated from secondary adrenal insufficiency using only a single aldosterone value. 11-Deoxycortisol, dehydroepiandrosterone, and a two-steroid profile each provided fair discrimination between secondary adrenal insufficiency and normal status. CONCLUSIONS: We conclude that stimulated levels of aldosterone, 11-deoxycortisol, dehydroepiandrosterone, and a two- or three-steroid profile provided additional discrimination between states of adrenal sufficiency and insufficiency. It is proposed that a steroid profile measuring cortisol, aldosterone, 11-deoxycortisol, and dehydroepiandrosterone would potentially improve the ability to determine the cause of adrenal insufficiency.     

Adrenocorticotropic Hormone Stimulation Test During High-Dose Glucocorticoid Therapy

ObjectiveTo define the effective time frame of adequate serum cortisol response to the short standard 250-μg adrenocorticotropic hormone stimulation test (ACTH-ST) after initiation of high-dose glucocorticoid therapy in order to assist in the diagnosis of adrenal insufficiency.MethodsWe performed an ACTH-ST at 4 different times in hospitalized patients, who had a documented intact hypothalamic-pituitary-adrenal axis and were receiving high-dose dexamethasone therapy for nonendocrine diseases, to determine the time until the serum cortisol response is compromised. The ACTH-ST was performed at the following time intervals after initiation of dexamethasone therapy—24, 48, 72, and 96 hours. The outcome measures were cortisol levels measured at 0, 30, and 60 minutes after administration of 250 μg of cosyntropin.ResultsOf the overall group of 11 study patients, all those (n = 8) tested within the first 72 hours after initiation of dexamethasone therapy had an adequate response (serum cortisol level at 60 minutes, ≥ 18 μg/dL). Two of the 3 patients tested at 96 hours after initiation of dexamethasone therapy had a suppressed cortisol response at 60 minutes. At 30 minutes, all cortisol levels except 1 were inadequate (< 18 μg/dL).ConclusionThis study suggests indirectly that the ACTH-ST may be used for the diagnosis of suspected adrenal insufficiency within the first 3 days after initiation of empiric glucocorticoid therapy. An inadequate response of serum cortisol at 60 minutes to the ACTH-ST may be indicative of adrenal insufficiency in this setting. Additional studies with more patients in each therapy time point are needed to confirm these initial results. (Endocr Pract. 2009;15:122-127)     

Serum Matrix Metalloproteinase-9 Levels in the Diagnosis of Functioning Adrena Tumors

ObjectiveTo investigate whether serum matrix metalloproteinase-9 (MMP-9) levels can be used as a diagnostic tool in determining the functioning status of benign adrenal tumors.MethodsIn this case-control study, medical records of patients with adrenal tumors who consecutively presented to an endocrinology clinic between August 2005 and October 2008 were evaluated. Operation was recommended when the incidentaloma was larger than 4 cm or when a hypersecreting tumor was suspected. A control group of healthy persons matched for age, body mass index, and sex was also enrolled. Patients underwent routine endocrinologic examinations. MMP-9 levels were compared preoperatively and postoperatively. Findings were compared among patients with functioning adrenal tumors, patients with nonfunctioning adrenal tumors, and control participants.ResultsOf 370 patients with adrenal tumors, 50 with adrenal incidentaloma met the inclusion criteria. Twenty- five healthy individuals were enrolled as controls. Group 1 included 20 patients with functioning adrenal tumors (14 with Cushing syndrome and 6 with pheochromocytoma), and Group 2 included 30 patients with nonfunctioning adrenal tumors. MMP-9 levels were higher in patients with nonfunctioning adrenal tumors and functioning adrenal tumors than in control participants (P < .001). MMP-9 levels in patients with functioning adrenal tumors were significantly higher than those in patients with nonfunctioning adrenal tumors (P = .002). After operation, levels decreased significantly in patients with Cushing syndrome and in those with pheochromocytoma; however, patients with Cushing syndrome and pheochromocytoma had similar MMP-9 levels preoperatively and postoperatively. No significant linear correlation existed between tumor volume and MMP-9 levels. A significant positive correlation was determined between preoperative MMP-9 concentrations and 24-hour urinary fractionated metanephrine and epinephrine (r = 0.938, P = .006; r = 0.965, P = .002, respectively), between MMP-9 levels and baseline cortisol levels (r = 0.402, P = .003), and between MMP-9 levels and cortisol levels obtained after dexamethasone suppression testing (r = 0.357, P = .006).ConclusionOur data suggest that serum MMP-9 levels may be useful in differentiating benign subclinical functioning adrenal tumors from benign nonfunctioning adrenal tumors. (Endocr Pract. 2010;16:419-427)     

Vitamin D Insufficiency is Associated With Reduced Parasympathetic Nerve Fiber Function in Type 2 Diabetes

ObjectiveVitamin D insufficiency is prevalent in subjects with type 2 diabetes mellitus (T2DM) and is associated with peripheral neuropathy. However, there are little data regarding vitamin D status in patients with cardiovascular autonomic neuropathy. Our objective was to evaluate the association of cardiovascular autonomic function, 25-hydroxyvitamin D (25[OH]D) insufficiency (i.e., levels < 30 ng/mL), and multiple metabolic parameters in subjects with T2DM.MethodsWe examined 50 individuals with T2DM. Cardiovascular autonomic function (i.e., parasympathetic function) was assessed by RR-variation during deep breathing (i.e., mean circular resultant [MCR] and expiration/inspiration [E/I] ratio). Metabolic parameters included measures of adiposity, glycemic control, insulin resistance, calcium metabolism, and 25(OH)D.ResultsParticipants with 25(OH)D insufficiency (n = 26) were younger (66 ± 9 vs. 60 ± 10 years, P < .05), more insulin resistant, had a higher body mass index (BMI) and lower adiponectin levels. The MCR (39.5 ± 26.3 vs. 27.6 ± 17.2, P < .01) and E/I ratio (1.21 ± 0.17 vs. 1.15 ± 0.09, P < .01) were lower for those with 25(OH)D insufficiency after controlling for age. A stepwise selection procedure regressing MCR and E/I ratio on a number of metabolic parameters resulted in a model identifying age and 25(OH)D insufficiency as significant determinants for both measures. The interaction of age × 25(OH)D insufficiency was also included (MCR model, R² = 0.491, P < .001; E/I ratio, R² = 0.455, P < .001). Neither glycemic control nor other metabolic parameters were selected.ConclusionOur results suggest that 25(OH)D insufficiency is associated with reduced parasympathetic function, with a stronger association in younger persons with T2DM. Studies are needed to determine if vitamin D supplementation into the sufficient range could prevent or delay the onset of cardiovascular autonomic dysfunction. (Endocr Pract. 2015;21:174-181)     

The beneficial effects of rosuvastatin are independent of zinc supplementation in patients with atherosclerosis

BackgroundStatins have multiple antiatherosclerotic effects, but can reduce blood plasma concentrations of minerals, including zinc. As zinc possesses antiinflammatory and antioxidant effects, low zinc status can promote injuries or inadequate tissue repair in endothelial cells. Metallothionein (MT) expression might modulate responses induced by statins in patients with atherosclerosis. However, research regarding mineral status and the use of statins is scarce. This study evaluated the effects of zinc supplementation on zinc status and expression of the zinc-dependent MT1F and MT2A genes in patients with atherosclerosis treated with rosuvastatin.MethodsA double-blind, randomized clinical trial was performed with 54 participants treated with 10 mg rosuvastatin for 4 months with or without zinc supplementation (30 mg/day). Diet, lipid profile, high-sensitivity reactive protein C (hs-CRP), plasma and erythrocyte zinc concentrations, erythrocyte superoxide dismutase (SOD) activity, and MT1F and MT2A genes expression were analyzed before and after intervention.ResultsRosuvastatin therapy was effective in reducing low- and non-high-density lipoprotein, total cholesterol, triglycerides, and hs-CRP levels, independent of zinc supplementation. Additionally, zinc treatment had no effect on SOD enzyme activity (P = 0.201), plasma (P > 0.671) and erythrocyte (P > 0.123) zinc concentrations, or the pattern of MT1F and MT2A genes expression (P = 0.088 and P = 0.229, respectively).ConclusionsThe effectiveness of rosuvastatin treatment is independent of the effects of zinc supplementation. Moreover, rosuvastatin treatment did not have a significant impact on zinc status or MT1F and MT2A genes expression in patients with atherosclerosis.     

Effect of Bromocriptine-Qr On Glycemic Control in Subjects with Uncontrolled Hyperglycemia On One or Two Oral Anti-Diabetes Agents

ObjectiveTo investigate the effect of Bromocriptine QR on glycemic control in patients with type 2 diabetes whose glycemia is poorly controlled on one or two oral anti-diabetes agents.MethodsFive hundred fifteen Type 2 Diabetes Mellitus (T2DM) subjects (ages 18 to 80 and average body mass index [BMI] of 32.7) with baseline HbA1c ≥ 7.5 and on one or two oral anti-diabetes (OAD) medications (metformin, sulfonylurea, and/or thiazolidinediones) were randomized 2:1 to bromocriptine-QR (1.6 to 4.8 mg/day) or placebo for a 24 week treatment period. Study investigators were allowed to adjust, if necessary, subject anti diabetes medications during the study to attempt to achieve glycemic control in case of glycemic deterioration. The impact of bromocriptine-QR treatment intervention on glycemic control was assessed in subjects on any one or two OADs (ALL treatment category) (N = 515), or on metformin with or without another OAD (Met/OAD treatment category) (N = 356), or on metformin plus a sulfonylurea (Met/SU treatment category) (N = 245) 1) by examining the between group difference in change from baseline a) concomitant OAD medication changes during the study, and b) HbA1c and 2) by determining the odds of reaching HbA1c of ≤ 7.0% on bromocriptine-QR versus placebo.ResultsSignificantly more patients (approximately 1.5 to 2-fold more; P < .05) intensified concomitant anti diabetes medication therapy during the study in the placebo versus the bromocriptine-QR arm. In subjects that did not change the intensity of the baseline diabetes therapy (72%), and that were on any one or two OADs (ALL), or on metformin with or without another OAD (Met/OAD), or on metformin plus sulfonylurea (Met/SU), the HbA1c change for bromocriptine-QR versus placebo was − 0.47 versus + 0.22 (between group delta of − 0.69, P < .0001), − 0.55 versus + 0.26 (between group delta of − 0.81, P < .0001) and − 0.63 versus + 0.20 (between group delta of − 0.83, P < .0001) respectively, after 24 weeks on therapy. The odds ratio of reaching HbA1c of ≤ 7.0% was 6.50, 12.03 and 11.45 (P < .0002) for these three groups, respectively.ConclusionIn T2DM subjects whose hyperglycemia is poorly controlled on one or two oral agents, bromocrip tine-QR therapy for 24 weeks can provide significant added improvement in glycemic control relative to adding placebo. (Endocr Pract. 2012;18:931-943)     

Evaluation of a method to measure long term cortisol levels

IntroductionElevated levels of cortisol are known to induce various symptoms and diseases, e.g. abdominal obesity, type 2 diabetes, osteoporosis and cardiovascular disease. Measuring serum, saliva and urine cortisol is limited to one time point. Measurement of cortisol in scalp hair is a recently developed method to measure long term cortisol levels. The aim of this study was to investigate whether hair cortisol is a feasible parameter to measure cortisol exposure.ExperimentalWe collected hair samples of 195 healthy individuals, 9 hypercortisolemic and one hypocortisolemic patient and measured hair cortisol levels. Cortisol was extracted from scalp hair using methanol and cortisol levels were measured using a salivary ELISA kit. Measurement of waist and hip circumferences and blood pressure was performed in 46 healthy subjects.ResultsWe found a positive correlation between hair cortisol and both waist circumference (r = 0.392, p = 0.007) and waist-to-hip ratio (WHR) (r = 0.425, p = 0.003). No correlations were found between hair cortisol levels and BMI, blood pressure or age. There was no decline in cortisol levels in six consecutive hair segments. Hair cortisol levels were elevated in patients with known hypercortisolism (p < 0.0001).ConclusionsHair cortisol was positively correlated with WHR, suggesting that hair cortisol reflects cortisol exposure at tissue level, which was also supported by elevated hair cortisol levels in hypercortisolemic patients and concordance between hair cortisol levels and clinical disease course. Cortisol levels in hair are slightly influenced by hair treatment but not by natural hair colour, use of hair products, gender or age.     

Ethnicity,Clothing Style,and Body Mass Index are Significant Predictors of Vitamin D Insufficiency in Germany

ObjectiveTo analyze risk factors for vitamin D insufficiency in Germany with respect to ethnicity, sex, and clothing style.MethodsWe analyzed the routine diagnostic workups of 1,231 adult (45.9 ± 17.9 years old) German (n = 1,034) and Turk residents (n = 197) referred with nonspecific symptoms to the Thyroid Centers at St. Elisabeth-Hospital in Dorsten, Germany and Bottrop, Germany to assess for metabolic diseases. All subjects underwent a routine examination that consisted of a questionnaire, lab tests for 25-hydroxyvitamin-D (25OHD), and thyroid profile. Turk females with traditional clothing (headscarf and covered legs and arms) were considered to wear “covered clothing.” Logistic-regression was performed to identify factors that could predict vitamin D deficiency (< 20 ng/ mL) and insufficiency (20-30 ng/mL).ResultsVitamin D insufficiency was seen in 33% of Germans and 74.1% of Turks, and vitamin D deficiency was present in 11.3% and 44.2% of Germans and Turks, respectively (P < .001). The mean 25OHD value in Turk females with covered clothes was lower than that in Turk females with conventional clothing (16.3 ± 12.3 vs. 27.2 ± 15.8, P < .001). Vitamin D insufficiency was present in 86.0% of Turk females with covered clothing versus 62.8% with conventional clothing (odds ratio [OR] = 3.6, P = .002). Ethnicity, body mass index (BMI), and clothing style were significant predictors of vitamin D deficiency and insufficiency by logistic regression (P < .001).Conclusions(1) Vitamin D insufficiency among Turk residents in Germany is higher compared to Germans. The highest prevalence was present in Turk females with covered clothing. (2) Monitoring vitamin D in Turk residents in Germany is warranted. (3) Vitamin D supplements and access to facilities with sunlight exposure for females with covered clothing and all individuals with poor diets or limited access to sun exposure may prevent future health burden due to vitamin D insufficiency. (Endocr Pract. 2015; 21:122-127)     

Quantification of 2-hydrazinopyridine derivatized steroid hormones in fathead minnow (Pimephales promelas) blood plasma using LC-ESI+/MS/MS

Fathead minnows (Pimephales promelas) comprise a species-of-choice for the hazard assessments of various environmental contaminants, including compounds capable of disrupting endocrine function. Towards this end, the use of liquid chromatography coupled with mass spectrometry (LC–MS) and/or tandem mass spectrometry (MS/MS) is gaining common use for the quantification of steroid hormones as biomarkers of endocrine stress in small-fish toxicological studies. In this work, 2-hydrazinopyridine (2-HP) was used to derivatize and quantify the physiologically relevant steroid hormones of: 17α-hydroxypregnenolone, progesterone, 11-ketotestosterone, 11-deoxycortisol and 17α,20β-dihydroxypregnenone, in the blood plasma of male and female fathead minnows. Liquid chromatographic separation was achieved using a Waters? Sunfire C₁₈ column (2.1 mm × 50 mm with a 3.5 μm particle size) and Milli-Q water:methanol (both with 0.1% formic acid) mobile phase over a gradient of 15 min. All mass analyses were conducted using electrospray ionization in the positive mode with tandem mass spectrometry (ESI+/MS/MS). This is the first such application of 2-HP derivatization for the quantifications of the structurally and functionally diverse C19 androgen of 11-ketotestosterone; C21 progestogens of 17α-hydroxypregnenolone, progesterone and17α,20β-dihydroxypregnenone; and C21 corticosteroid of 11-deoxycortisol, in fathead minnow blood plasma. The limits of detection (LOD) were set to the lowest calibration standard that gave a signal-to-background response of ≥3, and were: 0.16 ng/ml for progesterone, 0.63 ng/ml for 17α-hydroxypregnenolone, 11-deoxycortisol and 17α,20β-dihydroxypregnenone, and 1.25 ng/ml for 11-ketotestosterone. This study demonstrates the application of 2-HP derivatization for the analysis of a variety of steroid hormones representative of endocrine function in a species of fish commonly used in toxicological studies.     

Everyday discrimination and diurnal cortisol during adolescence

PurposeTo examine the associations of the frequency and type of everyday discrimination with diurnal cortisol and whether those associations depend upon adolescents' ethnicity and gender.MethodsAdolescents (N = 292, M_age = 16. 39 years, SD = 0.74; 58% female) reported the frequency of perceived everyday discrimination and whether they attributed that discrimination to race, gender, age, or height and weight. Five saliva samples were collected per day across 3 days and assayed for cortisol.ResultsHigher frequency of everyday discrimination was associated with greater total daily cortisol output (area under the curve; AUC), lower wake and bedtime levels of cortisol, and less of a decline in cortisol across the day. These associations generally did not depend upon ethnicity or gender and attributions for the discrimination were not as consequential as the actual frequency of any type of unfair treatment.ConclusionEveryday discrimination, regardless of its type, may contribute to heightened HPA activity among adolescents of different ethnic backgrounds and genders.     

Intraperitoneal kisspeptin-10 administration induces dose-dependent degenerative changes in maturing rat testes

AimsKisspeptin, a peptide secreted by hypothalamic neurons, is a critical regulator of reproduction and puberty but its role in the regulation of gonadal maturation in sexually immature males is elusive. The present study investigated the effects of 12 days of pulsatile kisspeptin administration on gonadotropins and testosterone release and maturation of immature male gonads.Main methodsKisspeptin-10 was administered intraperitoneally at different dosage concentrations (1 μg, 1 ng, and 10 pg) to 5 weeks old prepubertal male rats, twice daily for 12 days. Plasma LH, FSH and testosterone concentrations were measured through competitive-binding radioimmunoassay. Spermatogenesis was studied mainly at stage VII of the spermatogenic cycle through light and electron microscopy.Key findingsAt the end of the treatments plasma LH and testosterone concentrations were reduced significantly at 1 ng and 1 μg kisspeptin doses (P < 0.05; P < 0.01). Type A spermatogonia, preleptotene spermatocytes, pachytene spermatocytes, step 7 spermatids, elongated spermatids and daily sperm production decreased significantly (P < 0.05). Sertoli cell efficiency and total support capacity of Sertoli cells were reduced at all doses (P < 0.05). Meiotic index decreased (P < 0.05) at 1 μg dose only, whereas coefficient of mitosis increased at 1 ng and 1 μg (P < 0.01) kisspeptin doses. Histologically, degeneration of seminiferous tubules was evident showing tubular necrosis, multinucleated giant cell formation, intratubular vacuolization, widened lumen and deshaped germ cells. Marked ultrastructural changes characterized by thin basal laminae, enlarged intratubular spaces, abnormal acrosome and disrupted germ cells were noticeable.SignificanceIn conclusion long-term kisspeptin-10 administration negatively regulates gonadal maturation in prepubertal testes.     

Serum Free Cortisol During Glucagon Stimulation Test In Healthy Short-Statured Children And Adolescents

Objective: The total cortisol (TC) response may be measured during the glucagon stimulation test (GST) for growth hormone (GH) reserve in order to assess the integrity of the hypothalamic-pituitary-adrenal (HPA) axis. Measurements of TC are unreliable in conditions of albumin and cortisol-binding globulin (CBG) alterations (e.g., hypoproteinemia or CBG deficiency). We aimed to measure the serum free cortisol (sFC) response to the GST in children and adolescents and determine whether it could predict the GH response to glucagon stimulation.Methods: Infants and children with either short stature or growth attenuation who were referred for evaluation of GH reserve underwent the GST.Results: The study population consisted of 103 subjects (62 females), median age 3.9 years (range, 0.5–14). The mean basal and peak TC levels were 13.3 ± 6.7 μg/dL and 29.6 ± 8.8 μg/dL, respectively. The mean basal and peak sFC levels were 0.7 ± 0.8 μg/dL and 1.7 ± 1.1 μg/dL, respectively. There was a negative correlation between peak TC and age (r = -0.3, P = .007) but not between peak sFC and age (r = -0.09, P = .36). Ninety-five percent of the patients had peak TC levels >15.8 μg/dL and peak sFC levels >0.6 μg/dL.Conclusion: Our results on a cohort of healthy short-statured children can serve as reference values for the sFC response during GST. Based on these results, we propose peak TC levels >15.8 μg/dL and peak sFC levels >0.6 μg/dL for defining normalcy of the HPA axis during the GST in children and adolescents.Abbreviations:ACTH = adrenocorticotrophic hormoneBMI = body mass indexCBG = cortisol-binding globulinGH = growth hormoneGST = glucagon stimulation testHPA = hypothalamic-pituitary-adrenalSDS = standard deviation scoresFC = serum free cortisolTC = total cortisol     

Evaluation of Admission Blood Glucose Levels in The Intensive Care Unit

ObjectiveTo assess the availability and clinical value of blood glucose (BG) testing at the time of admission to the intensive care unit (ICU) after such testing was implemented as routine care in the ICU.MethodsWe studied ICU admission BG testing rates and the prevalence of hyperglycemia. In this effort, we assessed the frequency of baseline BG testing in 330 consecutive patients during a period of 3 months and then implemented routine BG monitoring in 1,147 consecutive ICU patients during a 7-month period.ResultsOf the total study population, 25% had previously diagnosed diabetes (PDD). At baseline, 70% had BG measured within 4 hours before or after ICU admission (99% of patients with and 60% of patients without PDD). After implementation of routine BG monitoring, there was a significant increase in testing (70% before versus 87% after, /40.001; 70% during the baseline 3-month period versus 93% in the final 3 months of the study, P < 0.001). In patients without PDD, 41% had BG levels ≥ 140 mg/dL, and 8% had BG concentrations ≥ 200 mg/dL. Overall in the ICU setting, 57% of BG values ≥ 140 mg/dL and 33% of BG levels > 200 mg/dL were in patients without PDD. Frequencies of BG testing by admission diagnosis included the following (at baseline and during the final 3 months after implementation of routine BG tests): post-surgical status (46%, 85%), peripheral vascular disease (51%, 90%), neurologic disease (52%, 83%), gastrointestinal disease (58%, 91%), infection (69%, 100%), and diabetes (100%, 100%).ConclusionRates of routine BG testing are low in ICU patients without PDD. Elevations in BG levels were detected in 41% of our study patients without PDD, suggesting that routine implementation of BG monitoring in an ICU will identify patients at increased risk for hyperglycemia-associated higher morbidity and mortality. (Endocr Pract. 2007;13:705-710)     

Zinc and glycemic control: A meta-analysis of randomised placebo controlled supplementation trials in humans

BackgroundImpaired zinc metabolism is prominent in chronic disorders including cardiovascular disease and diabetes. Zinc has the potential to affect glucose homeostasis in animals and humans and hence impact the risk of type 2 diabetes mellitus.MethodsA systematic review and meta-analysis of randomised placebo controlled trials was conducted to determine the effect of zinc supplementation on fasting blood glucose, HbA1c, serum insulin and serum zinc concentrations. Relevant studies for inclusion were identified from a literature search of electronic databases up to July 2011.ResultsFourteen reports (n = 3978 subjects) were included in the meta-analysis. In the overall analysis, a small but statistically significant reduction in fasting glucose concentrations was observed (?0.19 ± 0.08 mmol/L, P = 0.013) after zinc supplementation. HbA1c tended to decrease in zinc-supplemented individuals (?0.64 ± 0.36%, P = 0.072). No significant effect was observed for serum insulin concentrations. Plasma zinc concentrations increased significantly following supplementation (+4.03 ± 0.81 μmol/L, P = 0.001). In secondary analyses of participants with chronic metabolic disease (types 1 and 2 diabetes mellitus, metabolic syndrome and obesity), zinc supplementation produced a greater reduction in glucose concentrations (?0.49 ± 0.11 mmol/L, P = 0.001) compared to the effect that was observed in healthy participants.ConclusionThe significant albeit modest reduction in glucose concentrations and tendency for a decrease in HbA1c following zinc supplementation suggest that zinc may contribute to the management of hyperglycemia in individuals with chronic metabolic disease.     

Clinical Markers Implying the Need for Treatment in Women with Gestational Diabetes Mellitus

ObjectiveTo assess the association of the point-of-care hemoglobin A_1c (POC A1C), fasting blood glucose (FBG), and BMI with fetal macrosomia and the need for medication in women with gestational diabetes (GDM).MethodsPOC A1C, FBG, and BMI values at GDM diagnosis and fetal weight at delivery were obtained for women identified from a prospective patient registry. These outcomes were compared between women who did not require medication for GDM and women who did require medication.ResultsMean values of POC A1C, FBG, and BMI in 67 patients who required medication were higher than those in 71 patients who did not require medication (POC A1C: 5.72 ± 0.45% vs 5.35 ± 0.46% [P < .001]; FBG: 97.4 ± 12.3 mg/dL vs 86.4 ± 9.5 mg/dL [P < .001]; BMI: 35.4 ± 6.4 kg/m2 vs 30.4 ± 6.2 kg/m2 [P < .001]). There was a modest correlation between POC A1C and FBG (Spearman rho 0.4, P < .001) and between POC A1C and BMI (Spearman rho 0.366, P < .001). Maternal POC A1C was not correlated with fetal weight at delivery (Spearman rho –0.010, P = .915).ConclusionsHigher POC A1C, FBG, and BMI values were associated with the need for medication in women with GDM. The use of clinical markers to assess glycemic control sooner in pregnancy may lead to the earlier identification of women at risk for GDM and earlier intervention to decrease the risk for complications. (Endocr Pract. 2012;18:62-65)     

Differential alteration in peripheral T-regulatory and T-effector cells with change in P-glycoprotein expression in Childhood Nephrotic Syndrome: A longitudinal study

IntroductionChildhood Idiopathic Nephrotic Syndrome (INS) responds to glucocorticoid therapy, however, 60–80% of patients relapse and some of them become steroid non responsive. INS may occur because of T cell dysfunction, abnormal cytokines and podocytopathies which reverse on steroid treatment. The reason of relapses could be imbalances in T cells phenotypes and respective cytokines. Herein, we hypothesize that relapses in INS may occur due to imbalance in T-regulatory and T-effector cell with their respective cytokines and overexpression of P-gp on lymphocytes.MethodsThe frequency of peripheral blood CD4⁺CD25⁺FoxP3⁺ Treg, CD4⁺IFN-γ⁺ Th1 and CD4⁺IL-4⁺ Th2 lymphocytes and their respective cytokines and P-gp expression on peripheral blood lymphocytes (PBLs) were analyzed in INS patients at baseline (n = 26), during remission (n = 24) and at relapse (n = 15).ResultsCompared to baseline, the frequency of Tregs was significantly increased at remission and decreased during relapse. In contrast, the frequency of Th1 and Th2 lymphocytes was significantly decreased during remission and increased at the time of relapse. Similarly, expression of P-gp was significantly high at baseline and at the time of relapse as compared to remission. Levels of cytokines IL-10 and TGF-β in the supernatant of stimulated PBMCs was increased during remission and decreased during relapse. In contrast, levels of IFN-γ and IL-4 were decreased during remission and increased at the time of relapse.ConclusionsSteroid therapy in INS induces decreased P-gp expression on PBLs along with increased frequency and cytokine response of T-regulatory cells, and reduced frequency and respective cytokine response of Th1 and Th2 cells during remission. However, reversal in the frequency and respective cytokines of T-regs, Th1 and Th2, and P-gp expression on PBLs occurs during relapses on follow-up.