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IGF 1 LEVEL :
Human growth hormone is necessary for growth and a deficiency produces short people. GH does not actually stimulate growth directly, but causes the release of insulin-like growth factors, particularly insulin-like growth factor 1 or IGF-1. It is IGF-1 that is responsible for growth and it stimulates the synthesis of lean muscle mass in particular. Human IGF-1 levels vary with age; they are particularly high during puberty and by the age of 60 years they are only about half the average value (200 micrograms/liter) of a younger adult(2,3).
Experiments to increase IGF-1 levels in older men through injections of recombinant (synthetic) GH produced astounding results. An 8.8% increase in lean body mass, a 14.4% decrease in fatty tissue, a 1.6% increase in vertebral bone density, and a 7.1% increase in skin thickness were reported by American medical researchers in 1990. Their trial lasted a year and although the 21 participants all remained healthy except for one who developed prostate cancer, the researchers warned that side effects such as edema, hypertension, diabetes, and enlargement of the heart could occur with prolonged use of synthetic GH. Other researchers found that GH injections in young people produced larger muscles and kidneys. More recently GH injections have become popular among athletes as a super- efficient way to increase muscle mass and strength(1,4).
Growth hormone is naturally secreted by cells in the pituitary gland and acts on the liver to produce IGF- 1. IGF-1 levels are normally quite steady, but increase during periods of excessive stress, through exercise, and by consuming a diet rich in certain amino acids especially arginine, ornithine, glycine, and lysine. These amino acids act directly on the pituitary gland to stimulate the production of GH and its downstream fellow hormone, IGF-1. So why not just eat a lot of these amino acids if you want to grow bigger muscles? Unfortunately, or perhaps fortunately as we shall see later, stomach acid is very tough on amino acids and only 10% or less of them actually survive long enough to get into the blood stream. This is where GH enhancers play a role. These products use a patented process to protect the amino acids in the stomach and as a result 90% or more of them are absorbed into the blood stream. It is claimed that the resulting flooding of the pituitary gland with the raw materials it needs to produce growth hormone can result in IGF-1 level increases of 200% or more. Surprise, surprise! The body has a built- in mechanism to prevent IGF-1 levels from going too high. Somatostatin is released by the hypothalamus and its major role is to keep IGF-1 levels under control. Another challenge for supplement purveyors? Not really since GH enhancers also contain special peptides which suppress the natural release of somatostatin(1-3).
Now, why would the body go out of its way to prevent high IGF-1 levels when they result in rippling muscles, sculpted bodies, and virtual 10 to 20 year age reversal in older men? Why indeed? The answer is simple, excessive IGF-1 levels can make you very, very sick and yes, they can actually kill you! High IGF-1 levels in children who are not yet fully grown cause gigantism and excessive levels in adults are associated with acromegaly. Acromegaly is not a fun thing with such manifestations as fatigue, coarse facial features, headaches, decreased vision, congestive heart failure, kidney stones, joint pains, and of particular interest to young men, impotence and a lack of sexual desire. It is said that acromegalics look more like each other than like their own family members. As a matter of fact, some pictures of bodybuilders on GH enhancers look suspiciously like the classic depictions of acromegalics.
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Chemically defined sequential culture media for TH+ cell derivation from human embryonic stem cells
During the past few years several differentiation protocols to derive midbrain dopamine (DA) neurons from human embryonic stem (hES) cells have been developed, but the production of sufficient amounts of the ‘right’ therapeutic DA cells has not yet been accomplished. The aim of this study was to efficiently generate tyrosine hydroxylase (TH)-positive cells in vitro from our hES cells using a chemically defined culture system. At the end of differentiation, the vast majority of cells (>90%) were positive for both TH and β-tubulin isotype III (TuJ1). Other markers of dopaminergic cells, like dopamine transporter (DAT) and Nurr1 were also detected by immunofluorescence or RT–PCR. The functions of these cells were confirmed by measurements of DA release in vitro and by transplantation of derived cells into Parkinson's disease (PD) rats in vivo. We found these cells were able to release DA when depolarized by high K+. Moreover, 4 weeks after transplantation, the hES-derived cells could survive and reduce the apomorphine-induced rotation behaviour of the rats. In conclusion, the experimental system presented here provided a reliable protocol to produce a large number of hES-derived TH+ cells which may be used in cell therapy for PD in future.
Rho-associated kinase inhibitor Y-27632 promotes survival of cynomolgus monkey embryonic stem cells
Non-human primates are suitable models for preclinical research aimed at cell-replacement therapies. Recently, it has been reported that Rho-associated kinase inhibitor Y-27632 markedly reduced dissociation-induced apoptosis of human embryonic stem (hES) cells, and is expected as a novel supplement for hES cell maintenance or differentiation inductions; however, the effects of the chemical are still to be determined in model animals. Here, we demonstrated the effect of Y-27632 on cynomolgus monkey ES (cyES) cells. Also, in cyES cells, Y-27632 treatment dramatically improved the efficiency of colony formation from single cells without affecting the pluripotent state and karyotype. Y-27632 supplementation was also effective for feeder-free culture and differentiation induction. Neural stem cells directly induced from cyES cells could give rise to neurons, astrocytes and dopamine producing cells. The present result not only suggests that the chemical was effective for improving the culture system of primate ES cells, but also the similarity between cyES and hES cells regarding the reactions to the chemical, which might be further evidence that cyES cells are superior models for hES cells.
Fertility in a i(Xq) Klinefelter patient: importance of XIST expression level determined by qRT-PCR in ruling out Klinefelter cryptic mosaicism as cause of oligozoospermia
The presence of an isochromosome Xq in Klinefelter syndrome (KS) is an apparently rare condition. In all cases reported so far, patients showed the classic phenotype. We here describe a case of isochromosome Xq [47,X,i(Xq),Y] in a non-mosaic KS patient. The patient exhibited a normal androgenized phenotype, normal testes and normal cognitive abilities. Semen analysis revealed a medium oligozoospermia (5 x 106 spermatozoa/ml). After the patient underwent intracytoplasmic sperm injection, he generated two cytogenetically healthy normal females. Fluorescence in situ hybridization analysis showed the presence of a dicentric Xq chromosome that did not show the presence of residual Xp arm up to the 57,820,478 bp position (Xp 1.1) of X chromosome sequence. Preferential inactivation of Xq isochromosome was demonstrated by bromodeoxyuridine replication analysis and transcriptional silencing by DNA methylation at the HUMARA locus. Furthermore, we demonstrated by quantitative RT–PCR an active XIST RNA expression in blood lymphocytes from Klinefelter patients, comparable to that observed in control females and over 30 000-fold greater than in control males. In conclusion, this qRT–PCR approach could be useful for screening of prepuberty males and for diagnosis or exclusion of cryptic Klinefelter mosaics.
Different secretion patterns of matrix metalloproteinases and IL-8 and effect of corticotropin-releasing hormone in preterm and term cervical fibroblasts
The aims of the present study were to compare the levels of mRNA and protein expression of matrix metalloproteinase (MMP)-1, -3, -8 and -9 in human cervical tissue in preterm and term labor as well as not in labor and to determine if corticotropin-releasing hormone (CRH) has an effect on MMP-1, -3 and interleukin (IL)-8 secretion in both preterm and term cervical fibroblasts. Cervical biopsies were taken from 60 women: 18 at preterm labor, 7 at preterm not in labor, 18 at term labor and 17 at term not in labor. ELISA and Immulite were used for protein and real-time RT–PCR for mRNA analysis. Cervical fibroblast cultures were incubated for 18 h with different CRH concentrations (10–13–10–6 M). The mRNA expression of MMP-1, -3 and -9 was higher in laboring groups compared with term not in labor. Protein levels of MMP-8 and -9 were higher in term in labor group compared with non-laboring groups. There were no significant differences in mRNA and protein expression between the preterm and respective term control groups. CRH significantly increased secretion of IL-8 in preterm and term cervical fibroblasts compared with controls. The secretion of IL-8 and MMP-1 was significantly higher and MMP-3 secretion lower in preterm cervical fibroblasts. In conclusion, cervical ripening at preterm seems to be a similar inflammatory process as at term with CRH involved. However, preterm and term cervical fibroblasts might have different phenotypes based on different secretion patterns of IL-8, MMP-1 and MMP-3.
A single base-pair mutation in the 3'-untranslated region of HLA-G mRNA is associated with pre-eclampsia
Human leukocyte antigen-G (HLA-G) is a non-classical class I HLA molecule that is expressed by extravillous cytotrophoblast cells. This protein may play a critical role in the protection of cytotrophoblasts from maternal immune response, allowing these semi-allogeneic cells to invade the uterus unimpeded. We have demonstrated that diminished placental HLA-G expression is associated with pre-eclampsia. In order to explore fundamental mechanisms underlying this reduced HLA-G expression in pre-eclampsia, we looked for, and found by sequences analysis, a single base-pair mutation in the HLA-G gene 3'-untranslated region (3'UTR) adjacent to an AUUUA motif. This mutation is significantly associated with pre-eclampsia, the severe form being more strongly associated with homozygosity for this mutation than the mild form. Since the null allele was discovered in the HLA-G mRNA 3'UTR adjacent to an AUUUA motif, we also examined the effect of this mutation on HLA-G mRNA stability, and found that half-lives of HLA-G mRNA with the mutation were significantly shorter than without the mutation. These data provide evidence that this mutation could be one of the fundamental mechanisms for lower levels of placental HLA-G protein expression in patients with pre-eclampsia.
Elevated expression of CYP1A1 and {gamma}-SYNUCLEIN in human ectopic (ovarian) endometriosis compared with eutopic endometrium
Endometriosis is a debilitating disease in which apoptotic, genetic, immunological, angiogenic and environmental factors have been implicated. Endocrine-disrupting agents (e.g. dioxins) might be involved. Dioxins, via the arylhydrocarbon receptor (AhR), induce estrogen-metabolizing enzymes CYP1A1 and CYP1B1. Elevated expression of -SYNUCLEIN (-SYN) has been associated with hormone-related conditions. Tissue sets consisting of eutopic and ectopic (ovarian) endometrium from patients with stage 3 or 4 endometriosis were obtained. Following RNA extraction and reverse transcription, quantitative real-time reverse transcriptase–polymerase chain reaction was performed for anti-apoptotic B-cell leukaemia/lymphoma 2 (BCL-2), CYP1A1, CYP1B1, estrogen receptor (ER), ERβ and -SYN. Immunohistochemical analyses for -syn, ER, ERβ and CYP1A1 were also conducted. A 3–9-fold increase in intra-individual expression of CYP1A1 in ectopic (ovarian) endometrium compared with eutopic tissue was observed; immunohistochemical analyses pointed to CYP1A1 being localized to the glandular epithelium. This intra-individual expression profile was not observed for CYP1B1 or BCL-2. However, a 5–53-fold intra-individual increase in -SYN expression was also demonstrated in six of nine tissue sets (a further two showed an increase that was not considered significant) when comparing ectopic to eutopic endometrium; -syn positivity was associated with endothelial cells. An elevation in ERβ was also noted when comparing ectopic to eutopic endometrium; with regard to ER, this was inconsistent. These results suggest an up-regulation of dioxin-inducible CYP1A1 and -SYN occurs in endometriosis. Whether -syn may be a novel diagnostic marker for endometriosis remains to be ascertained.
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