100th anniversary of the discovery of the human adrenal fetal zone by Stella Starkel and Lesław Węgrzynowski: how far have we come?

Year 2010 marks a centennial anniversary of the description by Stella Starkel and LesĹaw WÄgrzynowski, Polish students of the Faculty of Medicine, University of LwĂłw, the fetal zone of the human fetal adrenal gland. In 1911 both, Starkel and WÄgrzynowski were graduated from the Faculty of Medicine of Lwow University. The paper appeared in the German Arch. Anat. Physiol. and its original title was "Beitrag zur Histologie der Nebeniere bei Feten und Kindern" ("Contribution to histology of adrenals of fetuses and children"). The studies were performed on 100 adrenal glands obtained from fetuses (from 6th month of gestation) and up to 5-year-old children. They described the fetal zone as a "medullary zone", also as "immature cortex", which undergoes involution in first years of life. To commemorate this discovery, this review aimed to present the most important achievements of studies on the development and involution of the human adrenal fetal zone

<i>KISS1</i> and KISS1R expression in the human and rat carotid body and superior cervical ganglion

KISS1 and its receptor, KISS1R, have both been found to be expressed in central nervous system, but few data are present in the literature about their distribution in peripheral nervous structures. Thus, the aim of the present study was to investigate, through immunohistochemistry, the expression and distribution of KISS1 and KISS1R in the rat and human carotid bodies and superior cervical ganglia, also with particular reference to the different cellular populations. Materials consisted of carotid bodies and superior cervical ganglia were obtained at autopsy from 10 adult subjects and sampled from 10 adult Sprague-Dawley rats. Immunohistochemistry revealed diffuse expression of KISS1 and KISS1R in type I cells of both human and rat carotid bodies, whereas type II cells were negative. In both human and rat superior cervical ganglia positive anti-KISS1 and -KISS1R immunostainings were also selectively found in ganglion cells, satellite cells being negative. Endothelial cells also showed moderate immunostaining for both KISS1 and KISS1R. The expression of both kisspeptins and kisspeptin receptors in glomic type I cells and sympathetic ganglion cells supports a modulatory role of KISS1 on peripheral chemoreception and sympathetic function. Moreover, local changes in blood flow have been considered to be involved in carotid body chemoreceptor discharge and kisspeptins and kisspeptin receptors have also been found in the endothelial cells. As a consequence, a possible role of kisspeptins in the regulation of carotid body blood flow and, indirectly, in chemoreceptor discharge may also be hypothesized

Lack of expression of preproorexin and orexin receptors genes in human normal and prostate cancer cell lines

Introduction. Studies on expression of orexins (OXs) and their receptors in human prostate gland and human prostatic cell lines are scanty and their results contradictory. Regarding this, we carefully reinvestigated this problem on human prostatic cell lines. Material and methods. Expression of preproorexin (ppOX) (6 primer pairs), and orexin receptors 1 and 2 (OXR1, OXR2) (4 and 2 primer pairs, respectively) was assessed by conventional PCR and QPCR in human normal (PrEC, PrSc, PrSmC) and prostate carcinoma (Du145, LNCaP, and PC3) cell lines. We designed intron spanning primers and also we applied primers from earlier publications and commercially available ones. Results. With the designed primer pairs, in all studied cell lines we failed to demonstrate expression of ppOX, OXR1 and OXR2 genes at the mRNA level, while reaction products were observed in control tissues (human placenta and adrenals). Primers applied in earlier studies did not form amplification products specific for preproorexin or orexin 1 receptor. Some commercially available primers for orexin receptor 1 produced false positive results. Conclusions. We found no evidence for the presence of preproorexin–orexin receptors system genes’ mRNAs in human prostate cell lines. The reported premises for these genes’ expression in prostate and prostatic cell lines may have arisen either from the presence of non-prostate cells included in the samples or from faulty PCR settings

Mitochondrial sirtuins in the rat adrenal gland: location within the glands of males and females, hormonal and developmental regulation of gene expressions

Introduction. Sirtuins are NAD dependent class III histone deacetylases. In adrenal cortex mitochondria are able to transform — via nicotinamide nucleotide transhydrogenase (NNT) — NAD into NADPH, which is required for steroidogenesis. These findings suggest that sirtuins expressed in mitochondria, Sirt3, Sirt4 and Sirt5, may be associated with adrenal steroidogenesis. Therefore, the purpose of this study was to characterize the expression of mitochondrial sirtuins (Sirt3–5) in individual compartments of rat adrenal cortex, their developmental regulation and to demonstrate whether their expression is dependent on adrenocorticotrophic hormone (ACTH) and Nampt (nicotinamide phosphoribosyltransferase also known as visfatin/PBEF), the rate-limiting enzyme in the regulation of mammalian NAD synthesis. Material and methods. Studies were performed on rat adrenal glands or on primary culture of rat adrenocortical cells. Expression of mitochondrial sirtuins (Sirt3–5) was evaluated by Affymetrix microarray system or QPCR. The bulk of data were extracted from our earlier experiments which have been reanalyzed in regard to Sirt3–5 mRNAs expression levels and — if necessary — validated by QPCR. Results. Sirt3–5 were expressed throughout the rat adrenal, with the highest expression level of Sirt5. The level of expression of all sirtuins is higher in the zona glomerulosa (ZG) and zona fasciculata/reticularis (ZF/R) than in the adrenal medulla. Sirt3 and Sirt5 expression levels were similar in adult male and female rats, while Sirt4 expression level was higher in females. As revealed by analysis of the available open database, no significant changes in Sirt3–5 expression levels in whole adrenal glands were observed up to week 104 of life of both male and female rats. Moreover, 60 min after intraperitoneal ACTH injection the expression level of Sirt3 in the en­tire gland was elevated while Sirt5 expression level lowered. On the other hand, chronic ACTH infusion (48 h) did not change expression of studied sirtuins. In cultured cells, ACTH greatly increased the expression levels of the Sirt4 and Sirt5. In cultured cells, Fk866 — a highly specific competitive inhibitor of Nampt — reduced expression level of Sirt5 only. In enucleation-induced regenerating rat adrenal, the expression levels of all studied sirtuins were significantly reduced in relation to the control group. Finally, in primary rat adrenal culture the FCS depletion elevates the Sirt3 and Sirt4 expression levels and downregulates Sirt5 expression. Conclusions. Sirt3–5 are expressed throughout the rat adrenal, with the highest expression levels in adrenal cortex. Performed experiments (ACTH stimulation, FCS depletion, regeneration) suggest that in the adrenal cortex, the mitochondrial Sirt5 is the primary mitochondrial sirtuin involved in regulating the biological activity of adrenocortical cells. Our results also suggest that normal levels of intracellular Nampt (iNampt) enzymatic activity are required to maintain normal (control) levels of Sirt5 mRNA in cultured cells

Expression of estrogen, estrogen related and androgen receptors in adrenal cortex of intact adult male and female rats

Introduction. Adrenocortical activity in various species is sensitive to androgens and estrogens. They may affect adrenal cortex growth and functioning either via central pathways (CRH and ACTH) or directly, via specific receptors expressed in the cortex and/or by interfering with adrenocortical enzymes, among them those involved in steroidogenesis. Only limited data on expression of androgen and estrogen receptors in adrenal glands are available. Therefore the present study aimed to characterize, at the level of mRNA, expression of these receptors in specific components of adrenal cortex of intact adult male and female rats. Material and methods. Studies were performed on adult male and female (estrus) Wistar rats. Total RNA was isolated from adrenal zona glomerulosa (ZG) and fasciculate/reticularis (ZF/R). Expression of genes were evaluated by means of Affymetrix® Rat Gene 1.1 ST Array Strip and QPCR. Results. By means of Affymetrix® Rat Gene 1.1 ST Array we examined adrenocortical sex differences in the expression of nearly 30,000 genes. All data were analyzed in relation to the adrenals of the male rats. 32 genes were differentially expressed in ZG, and 233 genes in ZF/R. In the ZG expression levels of 24 genes were lower and 8 higher in female rats. The more distinct sex differences were observed in the ZF/R, in which expression levels of 146 genes were lower and 87 genes higher in female rats. Performed analyses did not reveal sex differences in the expression levels of both androgen (AR) and estrogen (ER) receptor genes in the adrenal cortex of male and female rats. Therefore matrix data were validated by QPCR. QPCR revealed higher expression levels of AR gene both in ZG and ZF/R of male than female rats. On the other hand, QPCR did not reveal sex-related differences in the expression levels of ERα, ERβ and non-genomic GPR30 (GPER-1) receptor. Of those genes expression levels of ERα genes were the highest. In studied adrenal samples the relative expression of ERα mRNA was higher than ERβ mRNA. In adrenals of adult male and female rats expression levels of estrogen-related receptors ERRα and ERRβ were similar, and only in the ZF/R of female rats ERRγ expression levels were significantly higher than in males. We also analyzed expression profile of three isoforms of steroid 5α-reductase (Srd5a1, Srd5a2 and Srd5a3) and aromatase (Cyp19a1) and expression levels of all these genes were similar in ZG and ZF/R of male and female rats. Conclusions. In contrast to Affymetrix microarray data QPCR revealed higher expression levels of AR gene in adrenal glands of the male rats. In adrenals of both sexes expression levels of ERa, ERb, non-genomic GPR30 (GPER-1), ERR α and ERRβ receptors were comparable. The obtained results suggest that acute steroidogenic effect of estrogens on corticosteroid secretion may be mediated by non-genomic GPR30

Endothelin-1[1–31], acting as an ETA-receptor selective agonist, stimulates proliferation of cultured rat zona glomerulosa cells

AbstractEndothelin-1 (ET-1)[1–31] is a novel hypertensive peptide that mimics many of the vascular effects of the classic 21 amino acid peptide ET-1[1–21]. However, at variance with ET-1[1–21] that enhances aldosterone secretion from cultured rat zona glomerulosa (ZG) cells by acting via ETB receptors, ET-1[1–31] did not elicit such effect. Both ET-1[1–21] and ET-1[1–31] raised the proliferation rate of cultured ZG cells, the maximal effective concentration being 10−8 M. This effect was blocked by the ETA-receptor antagonist BQ-123 and unaffected by the ETB-receptor antagonist BQ-788. Quantitative autoradiography showed that ET-1[1–21] displaced both [125I]PD-151242 binding to ETA receptors and [125I]BQ-3020 binding to ETB receptors in both rat ZG and adrenal medulla, while ET-1[1–31] displaced only [125I]BQ-3020 binding. The tyrosine kinase (TK) inhibitor tyrphostin-23 and the p42/p44 mitogen-activated protein kinase (MAPK) inhibitor PD-98059 abolished the proliferogenic effect of ET-1[1–31], while the protein kinase-C (PKC) inhibitor calphostin-C significantly reduced it. ET-1[1–31] (10−8 M) stimulated TK and MAPK activity of dispersed ZG cells, an effect that was blocked by BQ-123. The stimulatory action of ET-1[1–31] on TK activity was annulled by tyrphostin-23, while that on MAPK activity was reduced by calphostin-C and abolished by either tyrphostin-23 and PD-98059. These data suggest that ET-1[1–31] is a selective agonist of the ETA-receptor subtype, and enhances proliferation of cultured rat ZG cells through the PKC- and TK-dependent activation of p42/p44 MAPK cascade

Transcriptome Profile in Unilateral Adrenalectomy-Induced Compensatory Adrenal Growth in the Rat

Compensatory adrenal growth evoked by unilateral adrenalectomy (hemiadrenalectomy) constitutes one of the most frequently studied in vivo models of adrenocortical enlargement. This type of growth has been quite well characterized for its morphological, biochemical, and morphometric parameters. However, the molecular basis of compensatory adrenal growth is poorly understood. Therefore, the aim of this study was to investigate the rat adrenal transcriptome profile during the time of two previously described adrenocortical proliferation waves at 24 and 72 h after unilateral adrenalectomy. Surgical removal of the left adrenal or a sham operation was accomplished via the classic dorsal approach. As expected, the weight of the remaining right adrenal glands collected at 24 and 72 h after hemiadrenalectomy increased significantly. The transcriptome profile was identified by means of Affymetrix® Rat Gene 2.1 ST Array. The general profiles of differentially expressed genes were visualized as volcano plots and heatmaps. Detailed analyzes consisted of identifying significantly enriched gene ontological groups relevant to adrenal physiology, by means of DAVID and GOplot bioinformatics tools. The results of our studies showed that compensatory adrenal growth induced by unilateral adrenalectomy exerts a limited influence on the global transcriptome profile of the rat adrenal gland; nevertheless, it leads to significant changes in the expression of key genes regulating the circadian rhythm. Our results confirm also that regulation of compensatory adrenal growth is under complex and multifactorial control with a pivotal role of neural regulatory mechanisms and a supportive role of other components