• Leydig
  • LH (in males sometimes called "interstitial cell-stimulating hormone") stimulates the Leydig cells to produce testosterone. (med-life.net)
  • In the " Sertoli cell only syndrome ," testicular tubules are abnormal but Leydig cells are normal. (med-life.net)
  • In acquired gonadal failure (due to destruction of the testicular tubules by infection, radiation, or other agents), the FSH level is often (but not always) elevated, whereas LH and testosterone levels are often normal (unless the degree of testis destruction is sufficient to destroy most of the Leydig cells, a very severe change). (med-life.net)
  • Estradiol is produced by action of aromatase mainly in the Leydig cells of the mammalian testis, but also by some germ cells and the Sertoli cells of immature mammals. (wikipedia.org)
  • Male to female sex reversal, however, does not occur because Leydig cells remain normal. (wikipedia.org)
  • Leydig cell hypoplasia (or aplasia) (LCH), also known as Leydig cell agenesis, is a rare autosomal recessive genetic and endocrine syndrome affecting an estimated 1 in 1,000,000 genetic males. (wikipedia.org)
  • It is characterized by an inability of the body to respond to luteinizing hormone (LH), a gonadotropin which is normally responsible for signaling Leydig cells of the testicles to produce testosterone and other androgen sex hormones. (wikipedia.org)
  • Leydig cell hypoplasia does not occur in biological females as they do not have either Leydig cells or testicles. (wikipedia.org)
  • A related condition is follicle-stimulating hormone (FSH) insensitivity, which presents with similar symptoms to those of Leydig cell hypoplasia but with the symptoms in the respective sexes reversed (i.e., hypogonadism and sexual infantilism in females and merely problems with fertility in males). (wikipedia.org)
  • Leydig cell hypoplasia is caused by genetic mutations in LHCGR, a gene which encodes the LH/hCG receptor. (wikipedia.org)
  • LH normally acts through the LH/hCG receptor to stimulate the growth of Leydig cells in the testicles and the production of androgens such as testosterone and dihydrotestosterone (DHT) by these cells. (wikipedia.org)
  • In Leydig cell hypoplasia however, there is a reduced capacity for the LH/hCG receptor to respond to LH. (wikipedia.org)
  • This results in hypoplasia or absence of Leydig cells, testicular atrophy, and lower than normal androgen levels. (wikipedia.org)
  • In the most severe form of the condition in which there is a complete lack of response of the Leydig cells to LH, androgen production by the testicles is virtually negligible and secondary sexual characteristics entirely fail to develop at puberty. (wikipedia.org)
  • Since the Sertoli cells are not affected by Leydig cell hypoplasia, anti-Müllerian hormone is secreted normally and so there are no Müllerian structures. (wikipedia.org)
  • Leydig cell hypoplasia type II can display either a pronounced rise of testosterone levels or no rise. (wikipedia.org)
  • In any case, the diagnosis is confirmed on biopsy of the testes, revealing either absent or hypoplastic Leydig cells. (wikipedia.org)
  • A diagnosis of Leydig cell hypoplasia is usually made in the neonatal period, following the discovery of ambiguous genitalia, or at puberty, when secondary sex characteristics fail to develop. (wikipedia.org)
  • Puberty is the most common time for Leydig cell hypoplasia to be diagnosed. (wikipedia.org)
  • Patients with Leydig cell hypoplasia may be treated with hormone replacement therapy (i.e., with androgens), which will result in normal sexual development and the resolution of most symptoms. (wikipedia.org)
  • Disorders of sex development Intersexuality, pseudohermaphroditism, and ambiguous genitalia Hypogonadism and hypogonadotropic hypogonadism Familial male-limited precocious puberty (or LH oversensitivity) Follicle-stimulating hormone insensitivity Gonadotropin-releasing hormone insensitivity Inborn errors of steroid metabolism Isolated 17,20-lyase deficiency Combined 17α-hydroxylase/17,20-lyase deficiency 17β-Hydroxysteroid dehydrogenase III deficiency Androgen insensitivity syndrome "OMIM Entry - # 238320 - LEYDIG CELL HYPOPLASIA, TYPE I". omim.org. (wikipedia.org)
  • Where are leydig cells found? (brainscape.com)
  • The surgically obtained testis biopsy accurately describes testis architecture, is the best technique to detect in situ neoplasia or cancer, and allows for the overall assessment of the interstitium (Leydig cell number and hypertrophy). (wikipedia.org)
  • sexual maturation
  • Derived from the Latin puberatum (age of maturity), the word puberty describes the physical changes to sexual maturation, not the psychosocial and cultural maturation denoted by the term adolescent development in Western culture, wherein adolescence is the period of mental transition from childhood to adulthood, which overlaps much of the body's period of puberty. (wikipedia.org)
  • testis
  • Development of Sertoli cells is directed by the testis-determining factor protein. (wikipedia.org)
  • ETS Related Molecule or ERM transcription factor ERM transcription factor - needed for maintenance of the spermatogonial stem cell in the adult testis. (wikipedia.org)
  • transferrin - a blood plasma protein for iron ion delivery The occluding junctions of Sertoli cells form the blood-testis barrier, a structure that partitions the interstitial blood compartment of the testis from the adluminal compartment of the seminiferous tubules. (wikipedia.org)
  • Because of the apical progression of the spermatogonia (sperm stem cells), the occluding junctions must be dynamically reformed and broken to allow the immunoidentical spermatogonia to cross through the blood-testis barrier so they can become immunologically unique. (wikipedia.org)
  • Sertoli cells control the entry and exit of nutrients, hormones and other chemicals into the tubules of the testis as well as make the adluminal compartment an immune-privileged site. (wikipedia.org)
  • Clusterin was first identified in ram rete testis fluid where it showed signs of clustering with rat sertoli cells and erythrocytes, hence its name. (wikipedia.org)
  • Johnsen proposed a more quantitative analysis of testis cellular architecture based on the concept that testis damage causes a successive disappearance of the most mature germ cell type. (wikipedia.org)
  • Ezrin: a regulator of actin microfilaments in cell junctions of the rat testis. (nih.gov)
  • Since ectoplasmic specialization (ES) is an F-actin-rich testis-specific anchoring junction-a highly dynamic ultrastructure in the seminiferous epithelium due to continuous transport of germ cells, in particular spermatids, across the epithelium during the epithelial cycle-it is conceivable that ERM proteins are playing an active role in these events. (nih.gov)
  • secretion
  • Klinefelter's syndrome exists in several variants, however, and in some cases LH levels may be within reference range (single LH samples also may be confusing because of the pulsatile nature of LH secretion). (med-life.net)
  • The nuclear isoform encodes a 49 kDa protein, while the secretory isoform, which is the main gene transcript, encodes a 75-80 kDa protein after maturation (glycosylation, secretion, and dimerization). (wikipedia.org)
  • germ line
  • In Drosophila, zygotic transcription of Vasa occurs at pole cells, and stays germ-line specific throughout the life of the organism. (wikipedia.org)
  • In P. hawaienis, Vasa transcript is uniformly distributed in the embryo and is localized depending on the stabilization of the 3'UTR (Untranslated Region) to the germ line cells. (wikipedia.org)
  • fetal
  • During the early stages of fetal development, the number of pancreatic alpha cells outnumbers the number of pancreatic beta cells. (wikipedia.org)
  • While the fetal pancreas has functional beta cells by 14 to 24 weeks of gestation, the amount of insulin that is released into the bloodstream is relatively low. (wikipedia.org)
  • proteins
  • This repair likely employs the process of non-homologous end joining involving XRCC1 and PARP1 proteins that are expressed in Sertoli cells. (wikipedia.org)
  • These proteins have been implicated in oncogenesis and in several developmental processes, including regulation of cell fate and embryogenesis. (wikipedia.org)
  • males
  • These individuals are also referred to as 'males with XXY syndrome' , or as 'XXY males' . (medindia.net)
  • This increased susceptibility in females compared to males is also present in animal models of autoimmune diseases such as spontaneous SLE in (NZBxNZW)F1 and NZM.2328 mice, experimental autoimmune encephalomyelitis (EAE) in SJL mice, thyroiditis, Sjogren's syndrome in MRL/Mp-lpr/lpr mice and diabetes in non-obese diabetic mice. (biomedcentral.com)
  • In both males and females, FSH stimulates the maturation of germ cells. (wikipedia.org)
  • Genetic
  • It is known as the forgotten syndrome, as it is a common yet under-diagnosed genetic condition, despite being described almost 70 years ago. (medindia.net)
  • regulates
  • In the cytoplasm, the protein regulates the microtubule network and, by extension, cell migration and polarity. (wikipedia.org)
  • apoptosis
  • Overexpression of the secretory CLU isoform protects the cell from apoptosis induced by cellular stress, such as chemotherapy, radiotherapy, or androgen/estrogen depletion. (wikipedia.org)
  • Other pathways CLU participates in to downplay apoptosis in tumor cells include the PI3K/AKT/mTOR pathway and NF-κB pathway. (wikipedia.org)
  • citation needed
  • Due to its highly negative charge, hCG may repel the immune cells of the mother, protecting the fetus during the first trimester[citation needed]. (wikipedia.org)
  • stem
  • The activity of the ribonucleoprotein enzyme telomerase is detectable in germ, stem and tumor cells. (beds.ac.uk)
  • The Vasa protein is found primarily in germ cells in embryos and adults, where it is involved in germ cell determination and function, as well as in multipotent stem cells, where its exact function is unknown. (wikipedia.org)
  • stimulate
  • CLU may promote tumorigenesis by facilitating BAX-KLU70 binding and, consequently, preventing BAX from localizing to the outer mitochondrial membrane to stimulate cell death. (wikipedia.org)
  • gene
  • The gene is highly conserved in species, and the protein is widely distributed in many tissues and organs, where it participates in a number of biological processes, including lipid transport, membrane recycling, cell adhesion, programmed cell death, and complement-mediated cell lysis. (wikipedia.org)
  • The vasa gene, is essential for germ cell development and was first identified in Drosophila melanogaster, but has since been found to be conserved in a variety of vertebrates and invertebrates including humans. (wikipedia.org)
  • tubular
  • Microdissection is also easier to apply in cases of Sertoli-cell only pattern, as there is a greater difference between tubular diameter size. (drkarenboyle.com)
  • Studies have shown that ezrin is also a constituent protein of the actin-based tunneling nanotubes (TNT) also known as intercellular bridges, which are transient cytoplasmic tubular ultrastructures that transport signals, molecules and even organelles between adjacent and distant cells in an epithelium to coordinate cell events that occur across an epithelium. (nih.gov)
  • known
  • therefore, elevated levels measured when the patient is not pregnant may lead to a cancer diagnosis and, if high enough, paraneoplastic syndromes, however, it is not known whether this production is a contributing cause, or an effect of carcinogenesis. (wikipedia.org)
  • regulate
  • In clear cell renal cell carcinoma, CLU functions to regulate ERK 1/2 signaling and matrix metallopeptidase-9 expression to promote tumor cell migration, invasion, and metastasis. (wikipedia.org)
  • Developing embryos and adults regulate Vasa expression to cell and tissue specific locations. (wikipedia.org)
  • tumor cells
  • Studies revealed that inhibition of CLU resulted in increased effectiveness of chemotherapeutic agents to kill tumor cells. (wikipedia.org)
  • organs
  • Androgenic effects include maturation of the sex organs, particularly the penis and the formation of the scrotum in the fetus, and after birth (usually at puberty) a deepening of the voice, growth of facial hair (such as the beard) and axillary (underarm) hair. (wikipedia.org)