Cortisol induces follicle regression, while FSH prevents cortisol-induced follicle regression in pigs.

During follicular development, a few dominant follicles develop to large antral dominant follicles, whereas the remaining follicles undergo atretic degeneration. Because vascularization on the follicular surface is a morphological feature of dominant follicles, we previously classified these follicles as vascularized follicles (VFs) and non-VFs (NVFs). In NVFs, progesterone producing genes were expressed similarly to that in VFs; however, the progesterone concentration in follicular fluid was low in large NVFs. Therefore, we estimated that progesterone is converted to cortisol, which induces the loss of follicular functions. In this study, we comparative analyzed the expression of genes for progesterone converting enzymes (Cytochrome (CYP)11B1, CYP21A2, Hydroxysteroid (HSD)11B2) and cortisol receptor (NR3C1) in VF and NVF granulosa cells. In NVFs, expression of cortisol producing genes (CYP11B1 and CYP21A2) was higher than in VFs. Expression of the gene for the cortisol metabolizing enzyme HSD11B2 in NVFs was significantly lower than in VFs. In NVFs, accompanied by increasing cortisol concentration in follicular fluid, apoptosis of granulosa and cumulus cells was observed. Cultivation with FSH and metyrapone (a CYP11B1 inhibitor) of NVF cumulus-oocyte complexes inhibited apoptosis of cumulus cells and induced cumulus cell proliferation and oocyte maturation. Cortisol-induced CYP11B1 and CYP21A2 expression, whereas FSH-induced HSD11B2 mRNA expression in VF granulosa cells in the presence of cortisol. Furthermore, an addition of 18ß-glycyrrhetinic acid (18-GA; a HSD17B2 inhibitor) to cortisol and FSH-containing medium increased apoptosis of VF granulosa cells. These results suggested that cortisol is a stimulatory factor that induces follicular atresia; furthermore, inhibition of cortisol production by FSH might increase the number of healthy preovulatory follicles in pigs.

Transcriptome characterization of BPG axis and expression profiles of ovarian steroidogenesis-related genes in the Japanese sardine.

BACKGROUND: The clupeoid fishes are ecologically and commercially important fish species worldwide that exhibit a high level of population fluctuation, accompanied by alteration of reproductive traits. However, knowledge about their reproductive physiology in order to understand mechanisms underlying such population dynamics is limited. The endocrine system along with the brain-pituitary-gonadal (BPG) axis is critical for regulating reproduction. The aims of this study were to provide transcript data and genes related to the BPG axis, and to characterize the expression profiles of ovarian steroidogenesis-related genes in the Japanese sardine (Sardinops melanostictus, Clupeidae). RESULTS: RNA sequencing was performed using the sardine brain, pituitary, and gonad in both sexes. A total of 290,119 contigs were obtained and 115,173 non-redundant ORFs were annotated. The genes differentially expressed between ovary and testis were strongly associated with GO terms related to gamete production. The tissue-specific profile of the abundance of transcripts was characterized for the major regulators in the BPG axis, such as gonadotropin-releasing hormone, gonadotropin, and steroidogenic enzyme. By comparing between ovary and testis, out of eight different 17ß-hydroxysteroid dehydrogenase (Hsd17b) genes identified, higher hsd17b7 expression was found in testis, whereas higher expression of hsd17b8, hsd17b10, hsd17b12a, and hsd17b12b was found in ovary. The cDNAs encoding key endocrine factors in the ovarian steroidogenic pathway were cloned, sequenced, and quantitatively assayed. In the pituitary, follicle-stimulating hormone beta peaked during vitellogenesis, while luteinizing hormone beta peaked at the completion of vitellogenesis. In the ovary, follicle-stimulating hormone receptor and luteinizing hormone receptor were upregulated from mid- to late phase of vitellogenesis. Furthermore, three steroidogenic enzyme genes (cyp11a1, cyp17a1, and cyp19a1a) gradually increased their expression during ovarian development, accompanying a rise in serum estradiol-17ß, while 3ß-hydroxysteroid dehydrogenase and steroidogenic acute regulatory protein did not change significantly. CONCLUSIONS: This is the first report of deep RNA sequencing analysis of Japanese sardine, in which many key genes involved in the BPG axis were identified. Expression profiles of ovarian steroidogenesis-related genes provide a molecular basis of the physiological processes underlying ovarian development in the sardine. Our study will be a valuable resource for clarifying the molecular biology of clupeoid fishes.

11ß-Hydroxysteroid dehydrogenases control access of 7ß,27-dihydroxycholesterol to retinoid-related orphan receptor γ.

Oxysterols previously were considered intermediates of bile acid and steroid hormone biosynthetic pathways. However, recent research has emphasized the roles of oxysterols in essential physiologic processes and in various diseases. Despite these discoveries, the metabolic pathways leading to the different oxysterols are still largely unknown and the biosynthetic origin of several oxysterols remains unidentified. Earlier studies demonstrated that the glucocorticoid metabolizing enzymes, 11ß-hydroxysteroid dehydrogenase (11ß-HSD) types 1 and 2, interconvert 7-ketocholesterol (7kC) and 7ß-hydroxycholesterol (7ßOHC). We examined the role of 11ß-HSDs in the enzymatic control of the intracellular availability of 7ß,27-dihydroxycholesterol (7ß27OHC), a retinoid-related orphan receptor γ (RORγ) ligand. We used microsomal preparations of cells expressing recombinant 11ß-HSD1 and 11ß-HSD2 to assess whether 7ß27OHC and 7-keto,27-hydroxycholesterol (7k27OHC) are substrates of these enzymes. Binding of 7ß27OHC and 7k27OHC to 11ß-HSDs was studied by molecular modeling. To our knowledge, the stereospecific oxoreduction of 7k27OHC to 7ß27OHC by human 11ß-HSD1 and the reverse oxidation reaction of 7ß27OHC to 7k27OHC by human 11ß-HSD2 were demonstrated for the first time. Apparent enzyme affinities of 11ß-HSDs for these novel substrates were equal to or higher than those of the glucocorticoids. This is supported by the fact that 7k27OHC and 7ß27OHC are potent inhibitors of the 11ß-HSD1-dependent oxoreduction of cortisone and the 11ß-HSD2-dependent oxidation of cortisol, respectively. Furthermore, molecular docking calculations explained stereospecific enzyme activities. Finally, using an inducible RORγ reporter system, we showed that 11ß-HSD1 and 11ß-HSD2 controlled RORγ activity. These findings revealed a novel glucocorticoid-independent prereceptor regulation mechanism by 11ß-HSDs that warrants further investigation.

Lipopolysaccharide Downregulates 11ß-Hydroxysteroid Dehydrogenase 2 Expression through Inhibiting Peroxisome Proliferator-Activated Receptor-γ in Placental Trophoblasts.

It is increasingly recognized that excessive glucocorticoids induce fetal intrauterine growth restriction (IUGR). Placental 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2), a glucocorticoid-catalyzing enzyme, prevents active glucocorticoids from maternal circulation into the fetus, thus protecting against IUGR. Previous studies demonstrated gestational LPS exposure caused fetal IUGR. The aim of the current study was to investigate the effects of LPS on 11ß-HSD2 in mice placentas and human placental trophoblasts. Pregnant ICR(CD-1) mice were i.p. injected with LPS (200 µg/kg) on gestational day 16. As expected, gestational LPS exposure downregulated 11ß-HSD2 in mice placentas. In vitro, LPS downregulated 11ß-HSD2 in human placental trophoblasts. Additional experiment showed that LPS, which activated NF-κB, suppressed rosiglitazone-induced activation of peroxisome proliferator-activated receptor-γ (PPARγ) in mice placentas and human placental trophoblasts. Moreover, NF-κB p65 knockdown and specific NF-κB inhibitor attenuated LPS-induced suppression of PPARγ nuclear translocation in human placental trophoblasts. In addition, NF-κB p65 knockdown attenuated LPS-induced downregulation of 11ß-HSD2 in human placental trophoblasts. Mechanically, LPS promoted physical interaction between NF-κB p65 and PPARγ in the cytoplasm and nucleus of placental trophoblasts. Finally, pretreatment with rosiglitazone, a PPARγ agonist, partially alleviated LPS-induced reduction of fetal weight and crown-rump length. Taken together, these results suggest that LPS downregulates 11ß-HSD2 through suppressing PPARγ in placental trophoblasts. Placental 11ß-HSD2 downregulation may contribute partially to LPS-induced fetal IUGR.

Endocrine modulation of Brucella abortus-infected osteocytes function and osteoclastogenesis via modulation of RANKL/OPG.

Osteoarticular brucellosis is the most frequent complication of active disease. A large amount of cells in bone are osteocytes. Since bone remodeling process is regulated by hormones we sought to study the effect of cortisol and DHEA in Brucella abortus-infected osteocytes. Cortisol treatment inhibited the expression of IL-6, TNF-α, MMP-2 and RANKL in B. abortus-infected osteocytes. DHEA could reverse the inhibitory effect of cortisol on MMP-2 production. B. abortus infection inhibited connexin 43 (Cx43) expression in osteocytes. This expression was increased when cortisol was incorporated during the infection and DHEA treatment partially reversed the effect of cortisol. Osteocytes-infected with B. abortus induced osteoclast's differentiation. Yet, the presence of cortisol, but not DHEA, during osteocyte infection inhibited osteoclastogenesis. Glucocorticoid receptor (GR) is implicated in the signaling of cortisol. Infection with B. abortus was able to increase GRα/ß ratio. Levels of intracellular cortisol are not only dependent on GR expression but also a result of the activity of the isoenzymes 11ß-hydroxysteroid dehydrogenase (11ß-HSD)-1 (cortisone to cortisol conversion), 11ß-HSD2 (cortisol to cortisone conversion). B. abortus infection increased 11ß-HSD 1/2 ratio and cortisone mimicked the effect of cortisol. Our results indicated that cortisol and DHEA could modulate osteocyte responses during B. abortus infection.

11ß-hydroxysteroid dehydrogenases-2 decreases the apoptosis of MC3T3/MLO-Y4 cells induced by glucocorticoids.

The aim of the present study was to confirm the role of 11ß-hydroxysteroid dehydrogenases type 2(11ß-HSD-2) in steroid induced osteonecrosis of the femoral head(SANFH). We cultured mouse bone-like cells (MLO-Y4) and mouse osteoblast-like cells (MC3T3-E1). After overexpressed 11ß-HSD-2 successfully, we induced cell apoptosis by dexamethasone (DXM). The level of cell apoptosis, the expression of Bcl-2 in MLO-Y4 cells and the expression of Fas and caspase8 in MC3T3-E1 cells were detected. Then, we constructed 11ß-HSD-2 siRNA plasmid and represented it on MLO-Y4/MC3T3-E1 Cells, to down-regulate the 11ß-HSD-2 expression. After that, we used dexamethasone to induce cell apoptosis. The level of cell apoptosis, the expression of Bcl-2 in MLO-Y4 cells and the expression of Fas and caspase8 in MC3T3-E1 cells were detected again. In the overexpression model of cells, we found that the amount of cell apoptosis, the expression of Fas and caspase8 in MC3T3-E1 cells are lower than that of control groups. The amount of cell apoptosis, the expression of Fas and caspase8 in MC3T3-E1 cells were more than before when we reduced the expression of 11ß-HSD-2. In our study, we concluded that 11ß-HSD-2 plays an important role in the development of bone or osteoblast cell apoptosis, and the decreased expression of 11ß-HSD-2 may aggravate steroid induced bone/osteoblast cell apoptosis.

Maternal chronic hypoxia increases expression of genes regulating lung liquid movement and surfactant maturation in male fetuses in late gestation.

KEY POINTS: Chronic fetal hypoxaemia is a common pregnancy complication associated with intrauterine growth restriction that may influence respiratory outcome at birth. We investigated the effect of maternal chronic hypoxia for a month in late gestation on signalling pathways regulating fetal lung maturation and the transition to air-breathing at birth using isobaric hypoxic chambers without alterations to maternal food intake. Maternal chronic hypoxia in late gestation increases fetal lung expression of genes regulating hypoxia signalling, lung liquid reabsorption and surfactant maturation, which may be an adaptive response in preparation for the successful transition to air-breathing at birth. In contrast to other models of chronic fetal hypoxaemia, late gestation onset fetal hypoxaemia promotes molecular regulation of fetal lung maturation. This suggests a differential effect of timing and duration of fetal chronic hypoxaemia on fetal lung maturation, which supports the heterogeneity observed in respiratory outcomes in newborns following exposure to chronic hypoxaemia in utero. ABSTRACT: Chronic fetal hypoxaemia is a common pregnancy complication that may arise from maternal, placental and/or fetal factors. Respiratory outcome of the infant at birth likely depends on the duration, timing and severity of the hypoxaemic insult. We have isolated the effect of maternal chronic hypoxia (MCH) for a month in late gestation on fetal lung development. Pregnant ewes were exposed to normoxia (21% O2 ) or hypoxia (10% O2 ) from 105 to 138 days of gestation (term ∼145 days). At 138 days, gene expression in fetal lung tissue was determined by quantitative RT-PCR. Cortisol concentrations were determined in fetal plasma and lung tissue. Numerical density of surfactant protein positive cells was determined by immunohistochemistry. MCH reduced maternal PaO2 (106 ± 2.9 vs. 47 ± 2.8 mmHg) and fetal body weight (4.0 ± 0.4 vs. 3.2 ± 0.9 kg). MCH increased fetal lung expression of the anti-oxidant marker CAT and decreased expression of the pro-oxidant marker NOX-4. MCH increased expression of genes regulating hypoxia signalling and feedback (HIF-3α, KDM3A, SLC2A1, EGLN-3). There was no effect of MCH on fetal plasma/lung tissue cortisol concentrations, nor genes regulating glucocorticoid signalling (HSD11B-1, HSD11B-2, NR3C1, NR3C2). MCH increased expression of genes regulating sodium (SCNN1-B, ATP1-A1, ATP1-B1) and water (AQP-4) movement in the fetal lung. MCH promoted surfactant maturation (SFTP-B, SFTP-D, ABCA3) at the molecular level, but did not alter the numerical density of surfactant positive cells in lung tissue. MCH in late gestation promotes molecular maturation of the fetal lung, which may be an adaptive response in preparation for the successful transition to air-breathing at birth.

Rooibos influences glucocorticoid levels and steroid ratios in vivo and in vitro: a natural approach in the management of stress and metabolic disorders?

SCOPE: To determine the effect of Rooibos (Aspalathus linearis) on glucocorticoid biosynthesis and inactivation in vivo and in vitro. METHODS AND RESULTS: Ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) analyses of in vivo studies showed that human Rooibos consumption increased cortisone plasma levels in males (p = 0.0465) and reduced cortisol:cortisone ratios in males and females (p = 0.0486) at risk for cardiovascular disease. In rats, corticosterone (CORT) (p = 0.0275) and deoxycorticosterone (p = 0.0298) levels as well as the CORT:testosterone ratio (p = 0.0009) decreased following Rooibos consumption. The inactivation of cortisol was investigated in vitro by expressing 11ß-hydroxysteroid dehydrogenase type 1 (11ßHSD1) and type 2 (11ßHSD2) in CHO-K1 cells. Rooibos inhibited 11ßHSD1, which resulted in a significant reduction in the cortisol:cortisone ratio (p < 0.01). No significant effect was detected on 11ßHSD2. In vitro studies in adrenal H295R cells showed that Rooibos and rutin, one of the more stable flavonoid compounds present in Rooibos, significantly reduced the levels of cortisol and CORT in cells stimulated with forskolin to mimic a stress response. CONCLUSION: In vivo studies demonstrate that Rooibos significantly decreased glucocorticoid levels in rats and steroid metabolite ratios linked to metabolic disorders--cortisol:cortisone in humans and CORT:testosterone in rats. Results obtained at cellular level elucidate possible mechanisms by which these effects were achieved.

Ceramicine B, a limonoid with anti-lipid droplets accumulation activity from Chisocheton ceramicus.

The Meliaceae family of plants has been shown to contain a vast number of compounds with the potential to be developed for medicinal purposes. We have previously reported the isolation of limonoids from a plant in the Meliaceae family named Chisocheton ceramicus. Ceramicine B was identified as an active compound in inhibiting lipid droplets accumulation (LDA) in the mouse preadipocyte cell line MC3T3-G2/PA6. The presence of ceramicine B was found to inhibit the expression of glucose transporter type 4, lipoprotein lipase, and 11-beta hydroxysteroid dehydrogenase mRNA, and also adipogenic master regulator, peroxisome proliferator-activated receptor-γ, and CCAAT-enhancer-binding protein-α (C/EBPα) mRNA. However, for early adipogenic regulators, such as C/EBPß and C/EBPδ, and intermediary adipogenic regulators, Krüppel-like factors were unaffected. Western blot analysis showed that ceramicine B was found to inhibit the phosphorylation of Forkhead box O1 (Foxo1), a key process in the insulin signaling pathway. This suggested that the mechanism of anti-LDA activity of ceramicine B was partly via the inhibition of Foxo1 phosphorylation.

Assessment of 11-ß hydroxysteroid dehydrogenase (11-ßHSD1) 4478T>G and tumor necrosis factor-α (TNF-α)-308G>A polymorphisms with obesity and insulin resistance in Asian Indians in North India.

11-ß hydroxysteroid dehydrogenase (11-ßHSD1), tumor necrosis factor-α (TNF-α) and their role in obesity, regional adiposity and insulin resistance has been sparsely evaluated. We determined the polymorphic status of 11-ßHSD1 4478T>G and TNF-α-308G>A in Asian Indians in north India. In this cross-sectional study (n = 498; 258 males, 240 females), association of genotypes (PCR­RFLP) of 11-ßHSD1 and TNF-α were analyzed with obesity [BMI ≥ 25 kg/m(2), percentage body fat (%BF by DEXA); subcutaneous and intra-abdominal fat area (L(2-3) level by single slice MRI) in a sub sample] and insulin resistance. 46 percent subjects had generalized obesity, 55 % abdominal obesity and 23.8 % were insulin resistant. Frequencies (%) of [T/T] and [T/G] genotypes of 11-ßHSD1 were 89.57 and 10.43 respectively. Homozygosity for 11-ßHSD1 4478G/G was absent with no association with parameters of obesity and insulin resistance. Frequencies (%) of TNF-α [G] and [A] alleles were 88 and 12 respectively. Higher frequency of variant -308[A/A] was observed in females versus males (p = 0.01). Females with at least one single A allele of TNF-α-308G>A had significantly high %BF and total skinfold, whereas higher values of waist hip ratio, total cholesterol, triglycerides and VLDL were observed in males. Subjects with even a single A allele in TNF-α genotype showed higher subscapular skinfold predisposing them to truncal subcutaneous adiposity (p = 0.02). Our findings of association of TNF-α-308G>A variant in females with obesity indices suggests a gender-specific role of this polymorphism in obesity. High truncal subcutaneous adiposity is associated with A allele of TNF-α-308G>A in this population.

Reduced cortisol metabolism during critical illness.

BACKGROUND: Critical illness is often accompanied by hypercortisolemia, which has been attributed to stress-induced activation of the hypothalamic-pituitary-adrenal axis. However, low corticotropin levels have also been reported in critically ill patients, which may be due to reduced cortisol metabolism. METHODS: In a total of 158 patients in the intensive care unit and 64 matched controls, we tested five aspects of cortisol metabolism: daily levels of corticotropin and cortisol; plasma cortisol clearance, metabolism, and production during infusion of deuterium-labeled steroid hormones as tracers; plasma clearance of 100 mg of hydrocortisone; levels of urinary cortisol metabolites; and levels of messenger RNA and protein in liver and adipose tissue, to assess major cortisol-metabolizing enzymes. RESULTS: Total and free circulating cortisol levels were consistently higher in the patients than in controls, whereas corticotropin levels were lower (P<0.001 for both comparisons). Cortisol production was 83% higher in the patients (P=0.02). There was a reduction of more than 50% in cortisol clearance during tracer infusion and after the administration of 100 mg of hydrocortisone in the patients (P≤0.03 for both comparisons). All these factors accounted for an increase by a factor of 3.5 in plasma cortisol levels in the patients, as compared with controls (P<0.001). Impaired cortisol clearance also correlated with a lower cortisol response to corticotropin stimulation. Reduced cortisol metabolism was associated with reduced inactivation of cortisol in the liver and kidney, as suggested by urinary steroid ratios, tracer kinetics, and assessment of liver-biopsy samples (P≤0.004 for all comparisons). CONCLUSIONS: During critical illness, reduced cortisol breakdown, related to suppressed expression and activity of cortisol-metabolizing enzymes, contributed to hypercortisolemia and hence corticotropin suppression. The diagnostic and therapeutic implications for critically ill patients are unknown. (Funded by the Belgian Fund for Scientific Research and others; ClinicalTrials.gov numbers, NCT00512122 and NCT00115479; and Current Controlled Trials numbers, ISRCTN49433936, ISRCTN49306926, and ISRCTN08083905.).

Association of 11ß-hydroxysteroid dehydrogenase type I expression and activity with estrogen receptor ß in adipose tissue from postmenopausal women.

OBJECTIVE: 11ß-Hydroxysteroid dehydrogenase type I (11ßHSD1) regenerates active cortisol from inert cortisone in adipose tissue. Elevated adipose tissue 11ßHSD1 activity is observed in obese humans and rodents, where it is linked to obesity and its metabolic consequences. Menopause is also associated with increased abdominal fat accumulation, suggesting that estrogen is also important in adipose tissue metabolism. The purpose of this current study was to establish whether estrogen signaling through estrogen receptor α (ER-α) and estrogen receptor ß (ER-ß) could influence 11ßHSD1 in premenopausal and postmenopausal adipose tissues. METHODS: Nineteen premenopausal (aged 26 ± 5 y; body mass index, 23.6 ± 1.6 kg/m) and 23 postmenopausal (aged 63 ± 4 y; body mass index, 23.4 ± 1.9 kg/m) healthy women were studied. Subcutaneous adipose tissue biopsies and fasting venous blood samples were taken. Body composition was measured by bioelectrical impedance analysis. Human Simpson-Golabi-Behmel syndrome adipocyte cells were treated with ER-α- and ER-ß-specific agonists for 24 hours. Basic anthropometric data, serum 17ß-estradiol and progesterone concentrations, ER-α and ER-ß messenger RNA (mRNA) levels, and 11ßHSD1 mRNA, protein, and activity levels were assessed. RESULTS: ER-ß and 11ßHSD1, but not ER-α, mRNAs were significantly increased in adipose tissue from postmenopausal women compared with premenopausal women. ER-ß had a significant positive correlation with the mRNA level of 11ßHSD1 in adipose tissue from premenopausal and postmenopausal women. This association between ER-ß and 11ßHSD1 was greatest in adipose tissue from postmenopausal women. In human Simpson-Golabi-Behmel syndrome adipocytes, diarylpropiolnitrile, a selective ER-ß agonist, increased 11ßHSD1 mRNA, protein, and activity levels. CONCLUSIONS: We conclude that, in adipose tissue, ER-ß-mediated estrogen signaling can up-regulate 11ßHSD1 and that this may be of particular importance in postmenopausal women.

The cortisol and androgen pathways cross talk in high temperature-induced masculinization: the 11ß-hydroxysteroid dehydrogenase as a key enzyme.

In many ectotherm species the gonadal fate is modulated by temperature early in life [temperature-dependent sex determination (TSD)] but the transducer mechanism between temperature and gonadal differentiation is still elusive. We have recently shown that cortisol, the glucocorticoid stress-related hormone in vertebrates, is involved in the TSD process of pejerrey, Odontesthes bonariensis. Particularly, all larvae exposed to a male-producing temperature (MPT, 29 C) after hatching showed increased whole-body cortisol and 11-ketotestosterone (11-KT; the main bioactive androgen in fish) levels and developed as males. Moreover, cortisol administration at an intermediate, mixed sex-producing temperature (MixPT, 24 C) caused increases in 11-KT and in the frequency of males, suggesting a relation between this glucocorticoid and androgens during the masculinization process. In order to clarify the link between stress and masculinization, the expression of hydroxysteroid dehydrogenase (hsd)11b2, glucocorticoid receptors gr1 and gr2, and androgen receptors ar1 and ar2 was analyzed by quantitative real time PCR and in situ hybridization in larvae reared at MPT, MixPT, and female-producing temperature (FPT, 17 C) during the sex determination period. We also analyzed the effects of cortisol treatment in larvae reared at MixPT and in adult testicular explants incubated in vitro. MPT and cortisol treatment produced significant increases in hsd11b2 mRNA expression. Also, gonadal explants incubated in the presence of cortisol showed increases of 11-KT levels in the medium. Taken together these results suggest that cortisol promotes 11-KT production during high temperature-induced masculinization by modulation of hsd11b2 expression and thus drives the morphogenesis of the testes.

Genetics of adrenocortical disease: an update.

PURPOSE OF REVIEW: Disease states characterized by abnormal cellular function or proliferation frequently reflect aberrant genetic information. By revealing disease-specific DNA mutations, we gain insight into normal physiology, pathophysiology, potential therapeutic targets and are better equipped to evaluate an individual's disease risks. This review examines recent advances in our understanding of the genetic basis of adrenal cortical disease. RECENT FINDINGS: Important advances made in the past year have included identification of KCNJ5 potassium channel mutations in the pathogenesis of both aldosterone-producing adenomas and familial hyperaldosteronism type III; characterization of phosphodiesterase 11A as a modifier of phenotype in Carney complex caused by protein kinase, cAMP-dependent, regulatory subunit, type-I mutations; the finding of 11ß-hydroxysteroid dehydrogenase type I mutations as a novel mechanism for cortisone reductase deficiency; and demonstration of potential mortality benefit in pursuing comprehensive presymptomatic screening for patients with Li-Fraumeni syndrome, including possible reduction in risks associated with adrenocortical carcinoma. SUMMARY: This research review provides a framework for the endocrinologist to maintain an up-to-date understanding of adrenal cortical disease genetics.

Gene expression of ACTH, glucocorticoid receptors, 11ßHSD enzymes, LH-, FSH-, GH receptors and aromatase in equine epididymal and testicular tissue.

Glucocorticoids (GCs) are important mediators of the stress response and have been implicated in the function and regulation of testicular functions in different species. In many tissues, intracellular glucocorticoid activity is controlled by either or both of the two known isoforms of 11ß-hydroxysteroid dehydrogenase (11ßHSD) type 1 and 2, which interconvert active and inactive GCs. Little is known about the effects of stress on fertility in the equine species. The main objective of the present study was to investigate the expression of receptors for GCs and adrenocorticotropic hormone [ACTH, melanocortin 2 receptor (MC2R)] as well 11ßHSD1 and 11ßHSD2 in male equine epididymal and testicular tissue. In addition, expression of aromatase P-450 and receptors for luteinizing hormone (LHR), follicle stimulating hormone (FSHR) and growth hormone (GHR) was studied. Reverse transcriptase PCR and quantitative real-time PCR were performed in tissue from the epididymis (caput and cauda) and testes collected from nine healthy mature stallions (age 4-10 years). mRNA for ACTH and GC receptors as well as 11ßHSD1 and -2 were found in epididymal and testicular tissue. Expression of the genes studied was always positive in testicular tissue, while it was inconsistent in epididymal tissue. Quantitative gene expression in relation to ß-actin and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was significantly correlated (R = 0.403, p < 0.001). Quantitative PCR in relation to ß-actin revealed significant differences in the gene expression of 11ßHSD1, 11ßHSD2, LHR, FSHR, MC2R and aromatase between tissue collected from caput epididymidis, cauda epididymidis and testicular parenchyma (p < 0.05). With GAPDH, differences between tissues were significant for 11ßHSD1, 11ßHSD2 and MC2R (p < 0.05) In addition, high concentrations of mRNA of aromatase and receptors of LH and FSH were found in testicular tissue, while a pronounced expression of GH receptor was present in epididymal tissue. The results support the hypothesis of an interaction between the pituitary-adrenal axis and testicular function in the stallion.

High and low protein∶ carbohydrate dietary ratios during gestation alter maternal-fetal cortisol regulation in pigs.

Imbalanced maternal nutrition during gestation can cause alterations of the hypothalamic-pituitary-adrenal (HPA) system in offspring. The present study investigated the effects of maternal low- and high-protein diets during gestation in pigs on the maternal-fetal HPA regulation and expression of the glucocorticoid receptor (GR), mineralocorticoid receptor (MR), 11ß-hydroxysteroid dehydrogenase 1 and 2 (11ß-HSD1 and 11ß-HSD2) and c-fos mRNAs in the placenta and fetal brain. Twenty-seven German Landrace sows were fed diets with high (HP, 30%), low (LP, 6.5%) or adequate (AP, 12.1%) protein levels made isoenergetic by varying the carbohydrate levels. On gestational day 94, fetuses were recovered under general anesthesia for the collection of blood, brain and placenta samples. The LP diet in sows increased salivary cortisol levels during gestation compared to the HP and AP sows and caused an increase of placental GR and c-fos mRNA expression. However, the diurnal rhythm of plasma cortisol was disturbed in both LP and HP sows. Total plasma cortisol concentrations in the umbilical cord vessels were elevated in fetuses from HP sows, whereas corticosteroid-binding globulin levels were decreased in LP fetuses. In the hypothalamus, LP fetuses displayed an enhanced mRNA expression of 11ß-HSD1 and a reduced expression of c-fos. Additionally, the 11ß-HSD2 mRNA expression was decreased in both LP and HP fetuses. The present results suggest that both low and high protein∶carbohydrate dietary ratios during gestation may alter the expression of genes encoding key determinants of glucocorticoid hormone action in the fetus with potential long-lasting consequences for stress adaptation and health.

11ß-Hydroxysteroid dehydrogenase-1 is a novel regulator of skin homeostasis and a candidate target for promoting tissue repair.

11ß-Hydroxysteroid dehydrogenase 1 (11ß-HSD1) catalyzes the interconversion of cortisone and cortisol within the endoplasmic reticulum. 11ß-HSD1 is expressed widely, most notably in the liver, adipose tissue, and central nervous system. It has been studied intensely over the last 10 years because its activity is reported to be increased in visceral adipose tissue of obese people. Epidermal keratinocytes and dermal fibroblasts also express 11ß-HSD1. However, the function of the enzymatic activity 11ß-HSD1 in skin is not known. We found that 11ß-HSD1 was expressed in human and murine epidermis, and this expression increased as keratinocytes differentiate. The expression of 11ß-HSD1 by normal human epidermal keratinocytes (NHEKs) was increased by starvation or calcium-induced differentiation in vitro. A selective inhibitor of 11ß-HSD1 promoted proliferation of NHEKs and normal human dermal fibroblasts, but did not alter the differentiation of NHEKs. Topical application of selective 11ß-HSD1 inhibitor to the dorsal skin of hairless mice caused proliferation of keratinocytes. Taken together, these data suggest that 11ß-HSD1 is involved in tissue remodeling of the skin. This hypothesis was further supported by the observation that topical application of the selective 11ß-HSD1 inhibitor enhanced cutaneous wound healing in C57BL/6 mice and ob/ob mice. Collectively, we conclude that 11ß-HSD1 is negatively regulating the proliferation of keratinocytes and fibroblasts, and cutaneous wound healing. Hence, 11ß-HSD1 might maintain skin homeostasis by regulating the proliferation of keratinocytes and dermal fibroblasts. Thus 11ß-HSD1 is a novel candidate target for the design of skin disease treatments.

11-Hydroxy-ß-steroid dehydrogenase gene expression in canine adipose tissue and adipocytes: stimulation by lipopolysaccharide and tumor necrosis factor α.

The enzyme 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD-1) is expressed in a number of tissues in rodents and humans and is responsible for the reactivation of inert cortisone into cortisol. Its gene expression and activity are increased in white adipose tissue (WAT) from obese humans and may contribute to the adverse metabolic consequences of obesity and the metabolic syndrome. The extent to which 11ß-HSD-1 contributes to adipose tissue function in dogs is unknown; the aim of the present study was to examine 11ß-HSD-1 gene expression and its regulation by proinflammatory and anti-inflammatory agents in canine adipocytes. Real-time PCR was used to examine the expression of 11ß-HSD-1 in canine adipose tissue and canine adipocytes differentiated in culture. The mRNA encoding 11ß-HSD-1 was identified in all the major WAT depots in dogs and also in liver, kidney, and spleen. Quantification by real-time PCR showed that 11ß-HSD-1 mRNA was least in perirenal and falciform depots and greatest in subcutaneous, omental, and gonadal depots. Greater expression was seen in the omental depot in female than in male dogs (P=0.05). Gene expression for 11ß-HSD-1 was also seen in adipocytes, from both subcutaneous and visceral depots, differentiated in culture; expression was evident throughout differentiation but was generally greatest in preadipocytes and during early differentiation, declining as cells progressed to maturity. The inflammatory mediators lipopolysaccharide and tumor necrosis factor α had a main stimulatory effect on 11ß-HSD-1 gene expression in canine subcutaneous adipocytes, but IL-6 had no significant effect. Treatment with dexamethasone resulted in a significant time- and dose-dependent increase in 11ß-HSD-1 gene expression, with greatest effects seen at 24 h (2 nM: approximately 4-fold; 20 nM: approximately 14-fold; P=0.010 for both). When subcutaneous adipocytes were treated with the peroxisome proliferator activated receptor γ agonist rosiglitazone, similar dose- and time-dependent effects were noted. However, no effects were seen when adipocytes from the gonadal WAT depot were treated with rosiglitazone. The induction of 11ß-HSD-1 expression, by the pro-inflammatory cytokine tumor necrosis factor α and by lipopolysaccharide may have implications for the pathogenesis of obesity and its associated diseases in the dog.

18ß-glycyrrhetinic acid inhibits periodontitis via glucocorticoid-independent nuclear factor-κB inactivation in interleukin-10-deficient mice.

BACKGROUND AND OBJECTIVE: 18ß-Glycyrrhetinic acid (GA) is a natural anti-inflammatory compound derived from licorice root extract (Glycyrrhiza glabra). The effect of GA on experimental periodontitis and its mechanism of action were determined in the present study. MATERIAL AND METHODS: Periodontitis was induced by oral infection with Porphyromonas gingivalis W83 in interleukin-10-deficient mice. The effect of GA, which was delivered by subcutaneous injections in either prophylactic or therapeutic regimens, on alveolar bone loss and gingival gene expressions was determined on day 42 after initial infection. The effect of GA on lipopolysaccharide (LPS)-stimulated macrophages, T cell proliferation and osteoclastogenesis was also examined in vitro. RESULTS: 18ß-Glycyrrhetinic acid administered either prophylactically or therapeutically resulted in a dramatic reduction of infection-induced bone loss in interleukin-10-deficient mice, which are highly disease susceptible. Although GA has been reported to exert its anti-inflammatory activity via downregulation of 11ß-hydroxysteroid dehydrogenase-2 (HSD2), which converts active glucocorticoids to their inactive forms, GA did not reduce HSD2 gene expression in gingival tissue. Rather, in glucocorticoid-free conditions, GA potently inhibited LPS-stimulated proinflammatory cytokine production and RANKL-stimulated osteoclastogenesis, both of which are dependent on nuclear factor-κB. Furthermore, GA suppressed LPS- and RANKL-stimulated phosphorylation of nuclear factor-κB p105 in vitro. CONCLUSION: These findings indicate that GA inhibits periodontitis by inactivation of nuclear factor-κB in an interleukin-10- and glucocorticoid-independent fashion.

Local metabolism of glucocorticoids and its role in rat adjuvant arthritis.

11beta-Hydroxysteroid dehydrogenase 1 (11HSD1) regulates local glucocorticoid activity and plays an important role in various diseases. Here, we studied whether arthritis modulates 11HSD1, what is the role of pro-inflammatory cytokines in this process and whether altered local metabolism of glucocorticoids may contribute to the feedback regulation of inflammation. Adjuvant arthritis increased synovial 11HSD1 mRNA and 11-reductase activity but treatments with tumor necrosis factor alpha (TNF-alpha) and interleukin 1beta (IL-1beta) antagonists etanercept and anakinra reduced 11HSD1 upregulation. Treatment with carbenoxolone, an 11HSD inhibitor, increased expression of TNF-alpha, cyclooxygenase 2, and osteopontin mRNA without any changes in the plasma levels of corticosterone. Similar changes were observed when arthritic rats were treated with RU486, an antagonist of GR. This study suggests that arthritis upregulates synovial 11HSD1, this upregulation is controlled by TNF-alpha and IL-1beta and that the increased supply of local corticosterone might contribute to feedback regulation of inflammation.