A systematic immunohistochemical survey of the distribution patterns of GH, prolactin, somatolactin, β-TSH, β-FSH, β-LH, ACTH, and α-MSH in the adenohypophysis of Oreochromis niloticus , the Nile tilapia

Fish pituitary plays a central role in the control of growth, development, reproduction and adaptation to the environment. Several types of hormone-secreting adenohypophyseal cells have been characterised and localised in diverse teleost species. The results suggest a similar distribution pattern among the species investigated. However, most studies deal with a single hormone or hormone family. Thus, we studied adjacent sections of the pituitary of Oreochromis niloticus, the tilapia, by conventional staining and immunohistochemistry with specific antisera directed against growth hormone (GH), prolactin (PRL), somatolactin (SL), thyrotropin (β-TSH), follicle-stimulating hormone (β-FSH), luteinising hormone (β-LH), adrenocorticotropic hormone (ACTH) and melanocyte-stimulating hormone (α-MSH). The pituitary was characterised by a close interdigitating neighbourhood of neurohypophysis (PN) and adenohypophysis. PRL-immunoreactive and ACTH-immunoreactive cells were detected in the rostral pars distalis. GH-immunoreactive cells were present in the proximal pars distalis (PPD). A small region of the PPD contained β-TSH-immunoreactive cells, and β-LH-immunoreactive cells covered approximately the remaining parts. Centrally, β-FSH-immunoreactive cells were detected in the vicinity of the GH-containing cells. Some of these cells also displayed β-LH immunoreactivity. The pars intermedia was characterised by branches of the PN surrounded by SL-containing and α-MSH-immunoreactive cells.The ACTH and α-MSH antisera were observed to cross-react with the respective antigens. This cross-reactivity was abolished by pre-absorption. We present a complete map of the distinct localisation sites for the classical pituitary hormones, thereby providing a solid basis for future research on teleost pituitar

Environmentally Relevant Concentrations of 17α-Ethinylestradiol (EE2) Interfere With the Growth Hormone (GH)/Insulin-Like Growth Factor (IGF)-I System in Developing Bony Fish

The aim of this study was to evaluate whether effects of environmental estrogens on fish growth and reproduction may be mediated via modulating the growth hormone (GH)/insulin-like growth factor I (IGF-I) system. To this end, developing male and female monosex populations of tilapia were exposed to 17α-ethinylestradiol (EE2) at 5 and 25 ng EE2/l water from 10-day postfertilization (DPF) until 100 DPF. Under exposure to both EE2 concentrations, sex ratio shifted toward more females and body length, and weight were significantly reduced in males. The growth-reducing effect was associated with significant changes in hepatic IGF-I expression, both in males and females and with significant alterations of IGF-I mRNA and GH mRNA in the brain. The changes in IGF-I and GH mRNA were accompanied by altered estrogen receptor α (ERα) expression in brain and liver. These findings point to an influence of estrogenic exposure on the endocrine GH/IGF-I axis. In addition, the EE2 treatment resulted in significant changes of ERα and IGF-I expression in ovaries and testis, suggesting that the estrogens interact not only with the endocrine but also with the autocrine/paracrine part of the IGF-I system. Overall, our results provide evidence that EE2 at environmentally relevant concentrations is able to interfere with the GH/IGF-I system in bony fish and that the impairing effects of estrogens reported on fish growth and reproductive functions may rather result from a cross talk between the sex steroid and the IGF-I system than be toxicologica

Organ-specific expression of IGF-I during early development of bony fish as revealed in the tilapia, Oreochromis niloticus , by in situ hybridization and immunohistochemistry: indication for the particular importance of local IGF-I

The cellular sites of insulin-like growth factor I (IGF-I) synthesis in the early developing tilapia (0-140 days post fertilization, DPF) were investigated. IGF-I mRNA and peptide appeared in liver as early as 4 DPF and in gastro-intestinal epithelial cells between 5-9 DPF. In exocrine pancreas, the expression of IGF-I started at 4 DPF and continued until 90DPF. IGF-I production was detected in islets at 6 DPF in non-insulin cells and occurred throughout life. In renal tubules and ducts, IGF-I production started at 8 DPF. IGF-I production in chondrocytes had its onset at 4 DPF, was more pronounced in growing regions and was also found in adults. IGF-I mRNA and peptide appeared in the cytoplasm of skeletal muscle cells at 4 DPF. In gill chloride cells, IGF-I production started at 6 DPF. At 13 DPF, IGF-I was detected in cardiac myocytes. IGF-I-producing epidermal cells appeared at 5 DPF. In brain and ganglia, IGF-I was expressed in virtually all neurones from 6 to 29 DPF, their number decreasing with age. Neurosecretory IGF-I-immunoreactive axons were first seen in the neurohypophysis around 17 DPF. Endocrine cells of the adenohypophysis exhibited IGF-I mRNA at 28 DPF and IGF-I immunoreactivity at 40 DPF. Thus, IGF-I appeared early (4-5 DPF), first in liver, the main source of endocrine IGF-I, and then in organs involved in growth or metabolism. The expression of IGF-I was more pronounced during development than in juvenile and adult life. Local IGF-I therefore seems to have a high functional impact in early growth, metabolism and organogenesi

Insulin-like growth factor I (IGF-I) in a growth-enhanced transgenic (GH-overexpressing) bony fish, the tilapia ( Oreochromis niloticus ): indication for a higher impact of autocrine/paracrine than of endocrine IGF-I

Several lines of growth hormone (GH)-overexpressing fish have been produced and analysed for growth and fertility parameters. However, only few data are available on the growth-promoting hormone insulin-like growth factor I (IGF-I) that mediates most effects of GH, and these are contradictory. Using quantitative real-time RT-PCR, radioimmunoassay, in situ hybridization, immunohistochemistry, and radiochromatography we investigated IGF-I and IGF binding proteins (IGFBPs) in an adult (17 months old) transgenic (GH-overexpressing) tilapia (Oreochromis niloticus). The transgenics showed an around 1.5-fold increase in length and an approximately 2.3-fold higher weight than the non-transgenics. Using radioimmunoassay, the serum IGF-I levels were lower (6.22±0.75ng/ml) in transgenic than in wild-type (15.01±1.49ng/ml) individuals (P=0.0012). Radioimmunoassayable IGF-I in transgenic liver was 4.2-times higher than in wild-type (16.0±2.21 vs. 3.83±0.71ng/g, P=0.0017). No hepatocytes in wild-type but numerous hepatocytes in transgenic liver contained IGF-I-immunoreactivity. RT-PCR revealed a 1.4-times higher IGF-I mRNA expression in the liver of the transgenics (10.51±0.82 vs. 7.3±0.49pg/μg total RNA, P=0.0032). In correspondence, in situ hybridization showed more IGF-I mRNA containing hepatocytes in the transgenics. A twofold elevated IGF-I mRNA expression was determined in the skeletal muscle of transgenics (0.33±0.02 vs. 0.16±0.01pg/μg total RNA, P<0.0001). Both liver and serum of transgenics showed increased IGF-I binding. The increased IGFBP content in the liver may lead to retention of IGF-I, and/or the release of IGF-I into the circulation may be slower resulting in accumulation of IGF-I in the hepatocytes. Our results indicate that the enhanced growth of the transgenics likely is due to enhanced autocrine/paracrine action of IGF-I in extrahepatic sites, as shown here for skeletal muscl

Effects of seawater and freshwater challenges on the Gh/Igf system in the saline-tolerant blackchin tilapia (Sarotherodon melanotheron)

Prolactin (Prl) and growth hormone (Gh) as well as insulin-like growth factor 1 (Igf1) are involved in the physiological adaptation of fish to varying salinities. The Igfs have been also ascribed other physiological roles during development, growth, reproduction and immune regulation. However, the main emphasis in the investigation of osmoregulatory responses has been the endocrine, liver-derived Igf1 route and local regulation within the liver and osmoregulatory organs. Few studies have focused on the impact of salinity alterations on the Gh/Igf-system within the neuroendocrine and immune systems and particularly in a salinity-tolerant species, such as the blackchin tilapia Sarotherodon melanotheron. This species is tolerant to hypersalinity and saline variations, but it is confronted by severe climate changes in the Saloum inverse estuary. Here we investigated bidirectional effects of increased salinity followed by its decrease on the gene regulation of prl, gh, igf1, igf2, Gh receptor and the tumor-necrosis factor a. A mixed population of sexually mature 14-month old blackchin tilapia adapted to freshwater were first exposed to seawater for one week and then to fresh water for another week. Brain, pituitary, head kidney and spleen were excised at 4 h, 1, 2, 3 and 7 days after both exposures and revealed differential expression patterns. This investigation should give us a better understanding of the role of the Gh/Igf system within the neuroendocrine and immune organs and the impact of bidirectional saline challenges on fish osmoregulation in non-osmoregulatory organs, notably the complex orchestration of growth factors and cytokines

Transcriptome-based network analysis reveals renal cell type-specific dysregulation of hypoxia-associated transcripts

Accumulating evidence suggests that dysregulation of hypoxia-regulated transcriptional mechanisms is involved in development of chronic kidney diseases (CKD). However, it remains unclear how hypoxia-induced transcription factors (HIFs) and subsequent biological processes contribute to CKD development and progression. In our study, genome-wide expression profiles of more than 200 renal biopsies from patients with different CKD stages revealed significant correlation of HIF-target genes with eGFR in glomeruli and tubulointerstitium. These correlations were positive and negative and in part compartment-specific. Microarrays of proximal tubular cells and podocytes with stable HIF1α and/or HIF2α suppression displayed cell type-specific HIF1/HIF2-dependencies as well as dysregulation of several pathways. WGCNA analysis identified gene sets that were highly coregulated within modules. Characterization of the modules revealed common as well as cell group- and condition-specific pathways, GO-Terms and transcription factors. Gene expression analysis of the hypoxia-interconnected pathways in patients with different CKD stages revealed an increased dysregulation with loss of renal function. In conclusion, our data clearly point to a compartment- and cell type-specific dysregulation of hypoxia-associated gene transcripts and might help to improve the understanding of hypoxia, HIF dysregulation, and transcriptional program response in CKD

Pathogens and host immunity in the ancient human oral cavity.

Calcified dental plaque (dental calculus) preserves for millennia and entraps biomolecules from all domains of life and viruses. We report the first, to our knowledge, high-resolution taxonomic and protein functional characterization of the ancient oral microbiome and demonstrate that the oral cavity has long served as a reservoir for bacteria implicated in both local and systemic disease. We characterize (i) the ancient oral microbiome in a diseased state, (ii) 40 opportunistic pathogens, (iii) ancient human-associated putative antibiotic resistance genes, (iv) a genome reconstruction of the periodontal pathogen Tannerella forsythia, (v) 239 bacterial and 43 human proteins, allowing confirmation of a long-term association between host immune factors, 'red complex' pathogens and periodontal disease, and (vi) DNA sequences matching dietary sources. Directly datable and nearly ubiquitous, dental calculus permits the simultaneous investigation of pathogen activity, host immunity and diet, thereby extending direct investigation of common diseases into the human evolutionary past

Ancient DNA Investigation of a Medieval German Cemetery Confirms Long-Term Stability of CCR5-∆32 Allele Frequencies in Central Europe

The CCR5-Δ32 mutation present in European populations is among the most prominently debated cases of recent positive selection in humans. This allele, a 32-bp deletion that renders the T-cell CCR5 receptor nonfunctional, has important epidemiological and public health significance, as homozygous carriers are resistant to several HIV strains. However, although the function of this allele in preventing HIV infection is now well described, its human evolutionary origin is poorly understood. Initial attempts to determine the emergence of the CCR5-Δ32 allele pointed to selection during the 14th-century Black Death pandemic; however, subsequent analyses suggest that the allele rose in frequency more than 5,000 years ago, possibly through drift. Recently, three studies have identified populations predating the 14th century CE that are positive for the CCR5-Δ32 allele, supporting the claim for a more ancient origin. However, these studies also suggest poorly understood regional differences in the recent evolutionary history of the CCR5-Δ32 allele. Here a new hydrolysis-probe-based real-time PCR assay was designed to ascertain CCR5 allele frequency in 53 individuals from a 10th- to 12th-century CE church and convent complex in central Germany that predates outbreaks of the Black Death pandemic. High-confidence genotypes were obtained for 32 individuals, and results show that CCR5-Δ32 allele frequency has remained unchanged in this region of Central Europe over the last millennium, suggesting that there has been no strong positive selective pressure over this time period and confirming a more ancient origin for the allele

Ancient DNA investigation of a medieval german cemetery confirms long-term stability of CCR5-Δ32 allele frequencies in Central Europe

The CCR5-Δ32 mutation present in European populations is among the most prominently debated cases of recent positive selection in humans. This allele, a 32-bp deletion that renders the T-cell CCR5 receptor nonfunctional, has important epidemiological and public health significance, as homozygous carriers are resistant to several HIV strains. However, although the function of this allele in preventing HIV infection is now well described, its human evolutionary origin is poorly understood. Initial attempts to determine the emergence of the CCR5-Δ32 allele pointed to selection during the 14th-century Black Death pandemic; however, subsequent analyses suggest that the allele rose in frequency more than 5,000 years ago, possibly through drift. Recently, three studies have identified populations predating the 14th century CE that are positive for the CCR5-Δ32 allele, supporting the claim for a more ancient origin. However, these studies also suggest poorly understood regional differences in the recent evolutionary history of the CCR5-Δ32 allele. Here a new hydrolysis-probe-based real-time PCR assay was designed to ascertain CCR5 allele frequency in 53 individuals from a 10th- to 12th-century CE church and convent complex in central Germany that predates outbreaks of the Black Death pandemic. High-confidence genotypes were obtained for 32 individuals, and results show that CCR5-Δ32 allele frequency has remained unchanged in this region of Central Europe over the last millennium, suggesting that there has been no strong positive selective pressure over this time period and confirming a more ancient origin for the allele

The Sommersdorf mummies-An interdisciplinary investigation on human remains from a 17th-19th century aristocratic crypt in southern Germany

Sommersdorf Castle (Bavaria, Germany) is a medieval castle complex which has been inhabited by the aristocratic family von Crailsheim. The deceased were entombed in a crypt located in the parapets underneath the castle's church, resulting in mummification of the bodies. Based on the family chronicle and oral history, identities have been ascribed to the mummies. The aim of the study is therefore to test the accuracy of the historical records in comparison to archaeological, anthropological and genetic data. Today, the crypt houses eleven wooden coffins from the 17th to 19th century AD. In ten of these, mummified and scattered human remains were found. Archive records were studied in order to identify names, ancestry, titles, occupation, date of birth and death, and place of interment of the individuals. The coffins were visually inspected and dated by typo-chronology, and the mummified and scattered skeletal remains were subjected to a physical anthropological examination. In total, the crypt contains the remains of a minimum number of nine individuals, among them three adult males, five adult females and one infant. A detailed scientific examination, including prior conservation, ancient DNA analyses, and computed tomography (CT), was performed on five mummies. By means of the CT data age at death, sex, body height, pathologies, and anatomical variants were investigated. CT analysis further showed that the bodies were naturally mummified. Mitochondrial DNA analyses revealed that the tested individuals are not maternally related. In addition, health, living conditions and circumstances of death of the entombed individuals could be highlighted. Being confronted with the strengths, weaknesses and limitations of each methodological approach, probable identification was achieved in two cases