Growth hormone (GH)

Overview

Growth hormone (GH), also called somatotropin, is a peptide hormone produced by the anterior pituitary gland and is a central regulator of postnatal growth, body composition, and metabolism. Its actions are mediated both directly and indirectly, in part through stimulation of insulin-like growth factor-1 (Insulin-like growth factor 1 (IGF-1)), which contributes to linear growth and tissue anabolism. GH secretion is pulsatile and is regulated by hypothalamic signals, nutritional status, sleep, and feedback from downstream hormones.

Clinically, GH is important in disorders of growth failure and in acromegaly, where excess GH production leads to elevated insulin-like growth factor 1 (IGF-1) and characteristic systemic complications. Recombinant GH and long-acting GH formulations are used therapeutically in selected pediatric and adult conditions, while biochemical assessment of GH and insulin-like growth factor 1 (IGF-1) remains essential for diagnosis, treatment monitoring, and evaluation of discordant hormone patterns.

Recent Publications Summary

Recent publications involving growth hormone (GH) focused largely on acromegaly, pituitary adenomas, and GH replacement strategies. In a 15-year single-center study, investigators compared clinical outcomes and pathological features of GH/prolactin (PRL)-positive adenomas with GH-only adenomas, reflecting ongoing interest in whether PRL co-expression has prognostic significance 42149337May. Another study examined postoperative biochemical discordance in surgically treated acromegaly, specifically cases in which GH and insulin-like growth factor 1 (IGF-1) were not concordant, highlighting the challenge this creates for assessing disease activity after surgery 42177388May.

Several case reports described complex pituitary tumors with GH co-secretion and the therapeutic implications of multimodal treatment. One patient with a giant prolactinoma masked by the hook effect was found on dilution testing to have extreme hyperprolactinaemia and additional GH excess; treatment with cabergoline improved symptoms and reduced tumor size, while pegvisomant normalized IGF-1 after lanreotide proved ineffective 42442850Jul. Another case of acromegaly due to a GH/PRL co-secreting macroadenoma with cavernous sinus invasion reported persistent biochemical and symptomatic disease despite surgery, radiotherapy, octreotide, cabergoline, and pegvisomant, but rapid IGF-1 normalization and complete headache resolution after pasireotide long-acting release 42394805Jul. A separate report described a mixed prolactin-secreting and GH-secreting pituitary macroadenoma in a man initially misdiagnosed as having glaucoma; after medical treatment the tumor shrank and vision improved, but later optic chiasm herniation into a secondary empty sella was identified as the cause of ongoing retinal nerve fiber layer loss 42481138Jul.

Other publications addressed GH therapy and GH-related metabolic effects outside the pituitary tumor setting. A randomized phase 3 trial evaluated once-weekly somapacitan, a long-acting GH, versus daily GH in children with Noonan syndrome, aiming to assess efficacy, safety, and tolerability while reducing injection burden 41774755Mar. In adults with GH deficiency, the foresiGHt trial assessed once-weekly lonapegsomatropin as a sustained-release alternative to daily somatropin 41420532Dec. In children born small for gestational age receiving GH, one study reported impaired glucose-insulin metabolism similar to that seen in children with obesity 41665939Feb. In juvenile rainbow trout, vaccination was associated with reduced length growth without changes in aerobic metabolism, and the authors suggested this effect was mediated through reduced IGF-1 production rather than altered energy expenditure 42119917May.

What Changes, What Holds

1. GH/PRL co-expression may matter for prognosis, but it does not yet replace standard acromegaly assessment
REINFORCES The new work keeps the baseline intact while suggesting a possible subclassification within GH-secreting pituitary adenomas. It does not alter the central account that GH excess drives acromegaly and that biochemical follow-up remains essential; instead, it asks whether PRL co-expression adds prognostic information in a subset of tumors 42149337May. The postoperative discordance study also reinforces the need to interpret GH and IGF-1 together rather than assume they will always align 42177388May.

2. Mixed pituitary tumors can defeat stepwise therapy and require individualized rescue strategies
NEW DIRECTION These reports extend the baseline by showing how GH excess behaves in complex, co-secreting adenomas and in treatment-refractory disease, a role the Overview does not specifically cover. They do not contradict GH’s established clinical importance; rather, they show that multimodal therapy may still fail and that alternative agents can produce late biochemical rescue in selected cases 42442850Jul42394805Jul. The practical message is that persistent disease after surgery, radiotherapy, and standard medical therapy may need unconventional sequencing.

3. Long-acting GH strategies are expanding replacement options, while metabolic monitoring remains necessary
REINFORCES The trial and related replacement study support the baseline’s statement that recombinant GH formulations are used therapeutically and that monitoring matters. They do not change what GH is or how it works; they sharpen the practical point that once-weekly preparations may reduce injection burden in replacement settings, while glucose-insulin effects still need attention in vulnerable groups such as children born small for gestational age 41774755Mar41420532Dec41665939Feb. The trout study is mechanistically suggestive but does not alter human GH biology 42119917May.

Overview update candidates: mixed pituitary tumor management may need individualized rescue strategies; long-acting GH formulations continue to expand replacement options; GH-treated children born small for gestational age may warrant closer glucose monitoring.