Peptide hormones as developmental growth and differentiation factors

Abstract

Peptide hormones, usually considered to be endocrine factors responsible for communication between tissues remotely located from each other, are increasingly being found to be synthesized in developing tissues, where they act locally. Several hormones are now known to be produced in developing tissues that are unrelated to the endocrine gland of origin in the adult. These hormones are synthesized locally, and are active as differentiation and survival factors, before the developing adult endocrine tissue becomes functional. There is increasing evidence for paracrine and/or autocrine actions for these factors during development, thus, placing them among the conventional growth and differentiation factors. We review the evidence for the view that thyroid hormones, growth hormone, prolactin, insulin, and parathyroid hormone-related protein are developmental growth and differentiation factors. Developmental Dynamics 237:1537-1552, 2008.

Postnatal leptin is necessary for maturation of numerous organs in newborn rats

“…18 Glucocorticoids, growth hormone, insulin-like growth factors, thyroid hormones, prolactin, estrogens and others additional hormones or cytokines act in a precise equilibrium to ensure harmonious development of the individual. 19,20 The known phenotype of genetically leptindeficient mice (ob/ob), which display numerous abnormal organ dysfunctions may, in fact, originate from developmental defects that are not well documented. The leptin antagonist used during our study constitutes a very powerful tool to understand the …”

Extrapituitary growth hormone

“…It is also present within the peripheral nervous system of chick embryos, particularly in the trigeminal and vagal nerves, the extensor nerve of the limb bud, and the ethmoid nerve in the head [14,17]. The presence of GH in these neural tissues occurs in the absence of pituitary GH, since GH secreting pituitary somatotrophs do not appear until ED 14-15 of chick embryogenesis [18,19]. At ED 14, GH in the brain was no longer widespread and restricted to specific tissues and cells.…”

Maternal Thyroid and Glucocorticoid Hormone Interactions in Larval Fish Development, and Their Applications in Aquaculture

“…Maternal compounds are supplemented by de novo embryonic mRNAs beginning in extremely early developmental stages, possibly directing tissue remodeling and differentiation processes as paracrine/autocrine factors (Sanders and Harvey, 2008).…”