Basics: Meds – Isturisa

Cushing’s disease is a progressive pituitary disorder in which there is an excess of cortisol in the body. While the disease can be treated surgically, this option is not possible for all patients. This is one of the approved medications that assist in controlling cortisol levels in people with Cushing’s disease.

sturisa was approved in 2020 to treat adults with Cushing’s disease for whom pituitary surgery is ineffective or not an option. The oral medication works by inhibiting an enzyme called 11-beta-hydroxylase, which is involved in cortisol production.

Isturisa, also known as osilodrostat or LCI699, is an approved treatment originally developed by Novartis, but now acquired by Recordati to treat people with Cushing’s disease, a condition in which a pituitary tumor causes the body to produce excessive levels of the stress hormone cortisol.

In 2020, the U.S. Food and Drug Administration (FDA) approved Isturisa to treat adults with Cushing’s disease for whom pituitary surgery was not an option, or ineffective.

Earlier that same year, the European Commission (EC) approved Isturisa to treat people with endogenous Cushing’s syndrome. The medication also was approved for the same indication in Japan in 2021.

How does Isturisa work?

Isturisa is an oral medicine that inhibits an enzyme called 11-beta-hydroxylase, which is involved in cortisol production. Blocking the activity of this enzyme prevents excessive cortisol production, normalizing the levels of the hormone in the body and easing the symptoms of Cushing’s disease.

Isturisa in clinical trials

A Phase 2 clinical trial (NCT01331239) investigated the safety and efficacy of Isturisa as a Cushing’s disease treatment. The trial that concluded in October 2019 initially was named LINC-1, but, through a study protocol amendment, patients who completed the study could continue into a second phase called LINC-2.

The company published findings that covered both patient groups in the journal Pituitary. Data showed that Isturisa reduced cortisol levels in the urine of all patients by week 22. Urine cortisol levels reached and remained within a normal range in 79% of the patients by then. Common adverse effects included nausea, diarrhea, lack of energy, and adrenal insufficiency — a condition in which the adrenal glands are unable to produce enough hormones.

A Phase 3 clinical trial (NCT02180217) called LINC-3 also assessed the safety and efficacy of Isturisa in 137 patients with Cushing’s disease (77% female, median age 40 years). Participants were given Isturisa for 26 weeks, with efficacy-based dose adjustments during the first 12 weeks.

Then, the 71 participants with a complete response (those whose urine cortisol levels were within normal limits) at week 26 and who did not require a dose increase after week 12, were assigned randomly to either continue treatment with Isturisa or switch to a placebo.

After this 34-week period, 86% of Isturisa-treated patients had normal urinary cortisol levels, as compared to 29% of participants given placebo. All participants then were given Isturisa for an additional 12 weeks. At the end of the 48-week study, 66% of participants had normal urine cortisol levels.

Results from LINC-3 formed the basis for regulatory approvals of Isturisa. Common adverse side effects in the trial included nausea, headache, fatigue, and adrenal insufficiency.

A multi-center, randomized, double-blind, placebo-controlled Phase 3 trial (NCT02697734) called LINC-4 further confirmed the safety and efficacy of Isturisa as a Cushing’s disease therapy. During the trial, patients received Isturisa or a placebo through a 12-week period followed by treatment with Isturisa until week 48.

Top-line results showed that 77% of patients on Isturisa experienced a complete response after the 12-week randomized period, as compared to 8% of those on placebo. No new safety data were noted.

A roll-over, worldwide Phase 2 study (NCT03606408) is recruiting patients who have successfully completed any of the previous clinical trials. Patients can continue to take the dosage they received during the initial trial. The aim of this study is to assess the long-term effects of Isturisa for up to five years.

ℹ️ Basics: Cushing’s Syndrome Overview

Cushing’s syndrome is a rare disorder that occurs when the body is exposed to too much cortisol. Cortisol is produced by the body and is also used in corticosteroid drugs. Cushing’s syndrome can occur either because cortisol is being overproduced by the body or from the use of drugs that contain cortisol (like  prednisone ).

Cortisol is the body’s main stress hormone. Cortisol is secreted by the adrenal glands in response to the secretion of adrenocorticotropic hormone (ACTH) by the pituitary. One form of Cushing’s syndrome may be caused by an oversecretion of ACTH by the pituitary leading to an excess of cortisol.

Cortisol has several functions, including the regulation of inflammation and controlling how the body uses carbohydrates, fats, and proteins. Corticosteroids such as prednisone, which are often used to treat inflammatory conditions, mimic the effects of cortisol.

Stay tuned for more basic info…

ℹ️ Basics: Testing: Dex Tests

Dexamethasone suppression test measures whether adrenocorticotrophic hormone (ACTH) secretion by the pituitary can be suppressed.

How the Test is Performed

During this test, you will receive dexamethasone. This is a strong man-made (synthetic) glucocorticoid medicine. Afterward, your blood is drawn so that the cortisol level in your blood can be measured.

There are two different types of dexamethasone suppression tests: low dose and high dose. Each type can either be done in an overnight (common) or standard (3-day) method (rare). There are different processes that may be used for either test. Examples of these are described below.

Common:

  • Low-dose overnight — You will get 1 milligram (mg) of dexamethasone at 11 p.m., and a health care provider will draw your blood the next morning at 8 a.m. for a cortisol measurement.
  • High-dose overnight — The provider will measure your cortisol on the morning of the test. Then you will receive 8 mg of dexamethasone at 11 p.m. Your blood is drawn the next morning at 8 a.m. for a cortisol measurement.

Rare:

  • Standard low-dose — Urine is collected over 3 days (stored in 24-hour collection containers) to measure cortisol. On day 2, you will get a low dose (0.5 mg) of dexamethasone by mouth every 6 hours for 48 hours.
  • Standard high-dose — Urine is collected over 3 days (stored in 24-hour collection containers) for measurement of cortisol. On day 2, you will receive a high dose (2 mg) of dexamethasone by mouth every 6 hours for 48 hours.

Read and follow the instructions carefully. The most common cause of an abnormal test result is when instructions are not followed.

How to Prepare for the Test

The provider may tell you to stop taking certain medicines that can affect the test, including:

  • Antibiotics
  • Anti-seizure drugs
  • Medicines that contain corticosteroids, such as hydrocortisone, prednisone
  • Estrogen
  • Oral birth control (contraceptives)
  • Water pills (diuretics)

How the Test will Feel

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.

Why the Test is Performed

This test is done when the provider suspects that your body is producing too much cortisol. It is done to help diagnose Cushing syndrome and identify the cause.

The low-dose test can help tell whether your body is producing too much ACTH. The high-dose test can help determine whether the problem is in the pituitary gland (Cushing disease) or from a different site in the body (ectopic).

Dexamethasone is a man-made (synthetic) steroid that binds to the same receptor as cortisol. Dexamethasone reduces ACTH release in normal people. Therefore, taking dexamethasone should reduce ACTH level and lead to a decreased cortisol level.

If your pituitary gland produces too much ACTH, you will have an abnormal response to the low-dose test. But you can have a normal response to the high-dose test.

Normal Results

Cortisol level should decrease after you receive dexamethasone.

Low dose:

  • Overnight — 8 a.m. plasma cortisol lower than 1.8 micrograms per deciliter (mcg/dL) or 50 nanomoles per liter (nmol/L)
  • Standard — Urinary free cortisol on day 3 lower than 10 micrograms per day (mcg/day) or 280 nmol/L

High dose:

  • Overnight — greater than 50% reduction in plasma cortisol
  • Standard — greater than 90% reduction in urinary free cortisol

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens. Talk to your doctor about the meaning of your specific test results.

What Abnormal Results Mean

An abnormal response to the low-dose test may mean that you have abnormal release of cortisol (Cushing syndrome). This could be due to:

The high-dose test can help tell a pituitary cause (Cushing disease) from other causes. An ACTH blood test may also help identify the cause of high cortisol.

Abnormal results vary based on the condition causing the problem.

Cushing syndrome caused by an adrenal tumor:

  • Low-dose test — no decrease in blood cortisol
  • ACTH level — low
  • In most cases, the high-dose test is not needed

Ectopic Cushing syndrome:

  • Low-dose test — no decrease in blood cortisol
  • ACTH level — high
  • High-dose test — no decrease in blood cortisol

Cushing syndrome caused by a pituitary tumor (Cushing disease)

  • Low-dose test — no decrease in blood cortisol
  • High-dose test — expected decrease in blood cortisol

False test results can occur due to many reasons, including different medicines, obesity, depression, and stress. False results are more common in women than men.

Most often, the dexamethasone level in the blood is measured in the morning along with the cortisol level. For the test result to be considered accurate, the dexamethasone level should be higher than 200 nanograms per deciliter (ng/dL) or 4.5 nanomoles per liter (nmol/L). Dexamethasone levels that are lower can cause a false-positive test result.

Risks

There is little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another, and from one side of the body to the other. Taking blood from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

  • Excessive bleeding
  • Fainting or feeling lightheaded
  • Multiple punctures to locate veins
  • Hematoma (blood accumulating under the skin)
  • Infection (a slight risk any time the skin is broken)

Alternative Names

DST; ACTH suppression test; Cortisol suppression test

References

Chernecky CC, Berger BJ. Dexamethasone suppression test – diagnostic. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. St Louis, MO: Elsevier Saunders; 2013:437-438.

Guber HA, Oprea M, Russell YX. Evaluation of endocrine function. In: McPherson RA, Pincus MR, eds. Henry’s Clinical Diagnosis and Management by Laboratory Methods. 24th ed. St Louis, MO: Elsevier; 2022:chap 25.

Newell-Price JDC, Auchus RJ. The adrenal cortex. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 15.

Review Date 5/13/2021

Updated by: Brent Wisse, MD, Board Certified in Metabolism/Endocrinology, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

From https://medlineplus.gov/ency/article/003694.htm

ℹ️ Basics: Adrenal Surgery: One Patient’s Experiences

Extracted and adapted from this series: https://cushings.invisionzone.com/topic/51040-on-my-way-to-getting-well/

Post 1) I was officially diagnosed with Cushing’s yesterday. I have a CT scan to check on my adrenal tumor and a meeting with my surgeon tomorrow. Hopefully they will schedule surgery for Monday or Tuesday. I have suffered over a year with this, been in congestive heart failure, and believe this cortisol caused my son to be stillborn in March. It’s been the year from hell. Please pray that all goes well tomorrow and that I will be cured of this once and for all!!

Post 2) Surgery set for the 23rd!!!!! He is planning a right adrenaltectomy. I am so darn excited…

Post 3) I’m almost two weeks out of adrenal surgery. He removed the tumor & my gland. This has been the hardest and most painful two weeks of my life. I am already noticing little changes in my body. My skin is getting texture, my hair is not as brittle, my swelling goes down each day, and my nails are white instead of yellow and are stronger. I am getting hair back on my arms, legs, & feet too. I can’t wait to continue to get well. I am ready to be able to get out and about. I am pretty much housebound now because of the pain of the withdrawal from the cortisol. I stay on my painkillers and rest in my recliner. Hubby bought it for me because I can’t sleep in the bed comfortably. He’s the best. He’s been sleeping on our air mattress in the living room with me for almost 2 weeks now. He is always there to help me get out of the recliner when I need to. He is amazing. Just wanted to update you all. Getting better everyday.

Post 4) I am on 40mg Hydrocortisone daily right now. I will have my first wean close to Christmas. I have an appt. on the 21st with my endo. She is fantastic and saved my life from this stuff. I am so blessed. Today is a rough day. I did have 2 good days in a row which was a huge blessing. Thanks for thinking of me!

Post 5) Well, I just survived month 1 of recovery. It was HORRIBLE. I have never had so much pain in my life. I am still on 40 mg and my endo. wants me to wean 10 mg starting on the 27th. We’ll see how it goes. I have so much pain, shaking, chills, no sleep NOW. I can’t imagine how its going to be on a lower dose. My cortisol level was SO HIGH (2107) before surgery. I knew this withdrawal was going to be terrible. SHe had never seen a level as high as mine before. The lab actually tested my urine twice because they didn’t believe it the first time. I am doing a lot of resting right now. I am very nervous about my mother leaving on New Year’s Day. I don’t know how I am going to handle my 3 year old on my own. I hurt so badly and my vision isn’t the greatest yet. Thanks for thinking of me and writing me back.

Post 6) We have another call into my endo about my suffering. I have done nothing but shake uncontrollably all day so far. I hurt so badly. I am up every hour at night writhing in pain. I refuse to suffer like this anymore. I want some relief. Thank you so much for all of the advice. It means the world to me. Great news is that I am off my BP meds as of today!! Cardiologist’s office said I could quit them. I am thrilled. Now to get this pain under control.

Post 7) Endo said we can do whatever I can tolerate. I am now doing 20/20/10 instead of 20/10/10. I am still in pain, but it’s a little more tolerable. She said if I am just miserable and can’t take the pain, then I can do a bedtime dose. I am going to try melatonin to help me sleep per her suggestion. She wants to see how I do on this new dose and start a slow wean in a few weeks.

Post 8) Things have been getting better by the week. New years day was my best physical and mental day so far. I can actually feel my old self returning! !! Today I have lots of bone/muscle pain. Its better than a few weeks ago by far. Yesterday I was able to enjoy my son and play with him for the first time in a long time. I could even dance a little with him. He was so happy. I am down to 20/17.5/10& am handling it well. The pain is tolerable. My hump is almost gone, my stomach is mushy and shrinking, skin is peeling and improving, hair is growing in normally. I will be six weeks out this Wed.

 

ℹ️ Basics: The Pituitary Gland: Small But Mighty

 

The pituitary gland works hard to keep you healthy, doing everything from ensuring proper bone and muscle growth to helping nursing mothers produce milk for their babies. Its functionality is even more remarkable when you consider the gland is the size of a pea.

“The pituitary is commonly referred to as the ‘master’ gland because it does so many important jobs in the body,” says Karen Frankwich, MD, a board-certified endocrinologist at Mission Hospital. “Not only does the pituitary make its own hormones, but it also triggers hormone production in other glands. The pituitary is aided in its job by the hypothalamus. This part of the brain is situated above the pituitary, and sends messages to the gland on when to release or stimulate production of necessary hormones.”

These hormones include:

  • Growth hormone, for healthy bone and muscle mass
  • Thyroid-stimulating hormone, which signals the thyroid to produce its hormones that govern metabolism and the body’s nervous system, among others
  • Follicle-stimulating and luteinizing hormones for healthy reproductive systems (including ovarian egg development in women and sperm formation in men, as well as estrogen and testosterone production)
  • Prolactin, for breast milk production in nursing mothers
  • Adrenocorticotropin (ACTH), which prompts the adrenal glands to produce the stress hormone cortisol. The proper amount of cortisol helps the body adapt to stressful situations by affecting the immune and nervous systems, blood sugar levels, blood pressure and metabolism.
  • Antidiuretic (ADH), which helps the kidneys control urine levels
  • Oxytocin, which can stimulate labor in pregnant women

The work of the pituitary gland can be affected by non-cancerous tumors called adenomas. “These tumors can affect hormone production, so you have too little or too much of a certain hormone,” Dr. Frankwich says. “Larger tumors that are more than 1 centimeter, called macroadenomas, can also put pressure on the area surrounding the gland, which can lead to vision problems and headaches. Because symptoms can vary depending on the hormone that is affected by a tumor, or sometimes there are no symptoms, adenomas can be difficult to pinpoint. General symptoms can include nausea, weight loss or gain, sluggishness or weakness, and changes in menstruation for women and sex drive for men.”

If there’s a suspected tumor, a doctor will usually run tests on a patient’s blood and urine, and possibly order a brain-imaging scan. An endocrinologist can help guide a patient on the best course of treatment, which could consist of surgery, medication, radiation therapy or careful monitoring of the tumor if it hasn’t caused major disruption.

“The pituitary gland is integral to a healthy, well-functioning body in so many ways,” Dr. Frankwich says. “It may not be a major organ you think about much, but it’s important to know how it works, and how it touches on so many aspects of your health.”

Adapted from http://www.stjhs.org/HealthCalling/2016/December/The-Pituitary-Gland-Small-but-Mighty.aspx

Thoughts? Share on the message boards.

ℹ️ Basics: Testing: IGF-1 (Insulin-like growth factor 1)

Aim—To contribute to the debate about whether growth hormone (GH) and insulin-like growth factor 1 (IGF-1) act independently on the growth process.

Methods—To describe growth in human and animal models of isolated IGF-1 deficiency (IGHD), such as in Laron syndrome (LS; primary IGF-1 deficiency and GH resistance) and IGF-1 gene or GH receptor gene knockout (KO) mice.

Results—Since the description of LS in 1966, 51 patients were followed, many since infancy. Newborns with LS are shorter (42–47 cm) than healthy babies (49–52 cm), suggesting that IGF-1 has some influence on intrauterine growth. Newborn mice with IGF-1 gene KO are 30% smaller. The postnatal growth rate of patients with LS is very slow, the distance from the lowest normal centile increasing progressively. If untreated, the final height is 100–136 cm for female and 109–138 cm for male patients. They have acromicia, organomicria including the brain, heart, gonads, genitalia, and retardation of skeletal maturation. The availability of biosynthetic IGF-1 since 1988 has enabled it to be administered to children with LS. It accelerated linear growth rates to 8–9 cm in the first year of treatment, compared with 10–12 cm/year during GH treatment of IGHD. The growth rate in following years was 5–6.5 cm/year.

Conclusion—IGF-1 is an important growth hormone, mediating the protein anabolic and linear growth promoting effect of pituitary GH. It has a GH independent growth stimulating effect, which with respect to cartilage cells is possibly optimised by the synergistic action with GH.

Keywords: insulin-like growth factor I, growth hormones, Laron syndrome, growth

In recent years, new technologies have enabled many advances in the so called growth hormone (GH) axis (fig 1). Thus, it has been found that GH secretion from the anterior pituitary is regulated not only by GH releasing hormone (GHRH) and somatostatin (GH secretion inhibiting hormone), but also by other hypothalamic peptides called GH secretagogues, which seem to act in synergism with GHRH by inhibiting somatostatin. One of these has been cloned and named Ghrelin. The interplay between GHRH and somatostatin induces a pulsatile GH secretion, which is highest during puberty. GH induces the generation of insulin-like growth factor 1 (IGF-1, also called somatomedin 1) in the liver and regulates the paracrine production of IGF-1 in many other tissues.

IGF-1

IGF-1 and IGF-2 were identified in 1957 by Salmon and Daughaday and designated “sulphation factor” by their ability to stimulate 35-sulphate incorporation into rat cartilage. Froesch et al described the non-suppressible insulin-like activity (NSILA) of two soluble serum components (NSILA I and II). In 1972, the labels sulphation factor and NSILA were replaced by the term “somatomedin”, denoting a substance under control and mediating the effects of GH. In 1976, Rinderknecht and Humbel isolated two active substances from human serum, which owing to their structural resemblance to proinsulin were renamed “insulin-like growth factor 1 and 2” (IGF-1 and 2). IGF-1 is the mediator of the anabolic and mitogenic activity of GH.

CHEMICAL STRUCTURE

The IGFs are members of a family of insulin related peptides that include relaxin and several peptides isolated from lower invertebrates. IGF-1 is a small peptide consisting of 70 amino acids with a molecular weight of 7649 Da. Similar to insulin, IGF-1 has an A and B chain connected by disulphide bonds. The C peptide region has 12 amino acids. The structural similarity to insulin explains the ability of IGF-1 to bind (with low affinity) to the insulin receptor.

THE IGF-1 GENE

The IGF-1 gene is on the long arm of chromosome 12q23–23. The human IGF-1 gene consists of six exons, including two leader exons, and has two promoters.

IGF binding proteins (IGFBPs)

In the plasma, 99% of IGFs are complexed to a family of binding proteins, which modulate the availability of free IGF-1 to the tissues. There are six binding proteins. In humans, almost 80% of circulating IGF-1 is carried by IGFBP-3, a ternary complex consisting of one molecule of IGF-1, one molecule of IGFBP-3, and one molecule of an 88 kDa protein named acid labile subunit. IGFBP-1 is regulated by insulin and IGF-1; IGFBP-3 is regulated mainly by GH but also to some degree by IGF-1.

The IGF-1 receptor

The human IGF-1 receptor (type 1 receptor) is the product of a single copy gene spanning over 100 kb of genomic DNA at the end of the long arm of chromosome 15q25–26. The gene contains 21 exons (fig 2) and its organisation resembles that of the structurally related insulin receptor (fig 3). The type 1 IGF receptor gene is expressed by almost all tissues and cell types during embryogenesis. In the liver, the organ with the highest IGF-1 ligand expression, IGF-1 receptor mRNA is almost undetectable, possibly because of the “downregulation” of the receptor by the local production of IGF-1. The type 1 IGF receptor is a heterotetramer composed of two extracellular spanning α subunits and transmembrane β subunits. The α subunits have binding sites for IGF-1 and are linked by disulphide bonds (fig 3). The β subunit has a short extracellular domain, a transmembrane domain, and an intracellular domain. The intracellular part contains a tyrosine kinase domain, which constitutes the signal transduction mechanism. Similar to the insulin receptor, the IGF-1 receptor undergoes ligand induced autophosphorylation. The activated IGF-1 receptor is capable of phosphorylating other tyrosine containing substrates, such as insulin receptor substrate 1 (IRS-1), and continues a cascade of enzyme activations via phosphatidylinositol-3 kinase (PI3-kinase), Grb2 (growth factor receptor bound protein 2), Syp (a phophotyrosine phosphatase), Nck (an oncogenic protein), and Shc (src homology domain protein), which associated to Grb2, activates Raf, leading to a cascade of protein kinases including Raf, mitogen activated protein (MAP) kinase, 5 G kinase, and others.

Physiology

IGF-1 is secreted by many tissues and the secretory site seems to determine its actions. Most IGF-1 is secreted by the liver and is transported to other tissues, acting as an endocrine hormone. IGF-1 is also secreted by other tissues, including cartilagenous cells, and acts locally as a paracrine hormone (fig 4). It is also assumed that IGF-1 can act in an autocrine manner as an oncogene. The role of IGF-1 in the metabolism of many tissues including growth has been reviewed recently.

Is IGF-1 “a” or “the” growth hormone?

The discussion on the role of IGF-1 in body growth will be based on growth in states of IGF-1 deficiency and the effects of exogenous IGF-1 administration. Experiments in nature (gene deletion or gene mutations) or experimental models in animals, such as gene knockouts, help us in this endeavour. In 1966 and 1968, we described a new type of dwarfism indistinguishable from genetic isolated GH deficiency (IGHD), but characterised by high serum GH values. Subsequent studies revealed that these patients cannot generate IGF-1.

This syndrome of GH resistance (insensitivity) was named by Elders et al as Laron dwarfism, a name subsequently changed to Laron syndrome (LS). Molecular studies revealed that the causes of GH resistance are deletions or mutations in the GH receptor gene, resulting in the failure to generate IGF-1 and a reduction in the synthesis of several other substances, including IGFBP-3. This unique model in humans has enabled the study of the differential effects of GH and IGF-1.

Growth and development in congenital (primary) IGF-1 deficiency (LS)

Our group has studied and followed 52 patients (many since birth) throughout childhood, puberty, and into adulthood. We found that newborns with LS are slightly shorter at birth (42–47 cm) than healthy babies (49–52 cm), suggesting that IGF-1 has some influence on intrauterine linear growth. This fact is enforced by the findings that already at birth, and throughout childhood, skeletal maturation is retarded, as is organ growth. These growth abnormalities include a small brain (as expressed by head circumference), a small heart (cardiomicria), and acromicria (small chin, resulting from underdevelopment of the facial bones, small hands, and small feet). IGF-1 deficiency also causes underdevelopment and weakness of the muscular system, and impairs and weakens hair and nail growth. These findings are identical to those described in IGHD. IGF-1 deficiency throughout childhood causes dwarfism (final height if untreated, 100–135 cm in female and 110–142 cm in male patients), with an abnormally high upper to lower body ratio. One patient reported from the UK was found to have a deletion of exons 4 and 5 of the IGF-1 gene and he too was found to have severe growth retardation.

Impaired growth and skeletal development in the absence of IGF-1 were confirmed in mice using knockout (KO) of the IGF-1 gene or GH receptor gene.

Knockout of the IGF-1 gene or the IGF-1 receptor gene reduces the size of mice by 40–45%. Lack of the IGF-1 receptor is lethal at birth in mice owing to respiratory failure caused by impaired development of the diaphragm and intercostal muscles. In another model, the mice remained alive and their postnatal growth was reduced.

In conclusion, findings in humans and in animals show that IGF-1 deficiencies causes pronounced growth retardation in the presence of increased GH values.

The following is a summary of the results of the growth stimulating effects of the administration of exogenous IGF-1 to children and experimental data.

Growth promoting effects of IGF-1

The first demonstration that exogenous IGF-1 stimulates growth was the administration of purified hormone to hypophysectomised rats. After the biosynthesis of IGF-1 identical to the native hormone, trials of its use in humans were begun; first in adults and then in children. Our group was the first to introduce long term administration of biosynthetic IGF-1 to children with primary IGF-1 deficiency—primary GH insensitivity or LS. The finding that daily IGF-1 administration raises serum alkaline phosphatose, which is an indicator of osteoblastic activity, and serum procollagen, in addition to IGFBP-3, led to long term treatment. Treatment of patients with LS was also initiated in other parts of the world. The difference between us and the other groups was that we used a once daily dose, whereas the others administered IGF-1 twice daily. Table 1 compares the linear growth response of children with LS treated by four different groups. It can be seen that before treatment the mean growth velocity was 3–4.7 cm/year and that this increased after IGF-1 treatment to 8.2–9.1 cm/year, followed by a lower velocity of 5.5–6.4 cm/year in the next two years. (In GH treatment the highest growth velocity registered is also in the first year of treatment.) Figure 5 illustrates the growth response to IGF-1 in eight children during the first years of treatment. Ranke and colleagues reported that two of their patients had reached the third centile (Tanner), as did the patient of Krzisnik and Battelino; however, most patients did not reach a normal final height. The reasons may be late initiation of treatment, irregular IGF-1 administration, underdosage, etc. Ranke et al conclude that long term treatment of patients with LS promoted growth and, if treatment is started at an early age, there is a considerable potential for achieving height normalisation. Because no patient in our group was treated since early infancy to final height we cannot confirm this opinion.

Table 1

Linear growth response of children with Laron syndrome treated by means of insulin-like growth factor 1 (IGF-1)

At start Growth velocity (cm/year) Year of treatment
Authors Year Ref. N Age range (years) BA (years) Ht SDS (m) IGF-1 dose (μg/kg/day) 0 1st 2nd 3rd
(n = 26) (n = 18)
Ranke et al 1995 31 3.7–19 1.8–13.3 −6.5 40–120 b.i.d. 3.9 (1.8) 8.5 (2.1) 6.4 (2.2)
(n = 5) (n = 5) (n = 1)
Backeljauw et al 1996 5 2–11 0.3–6.8 −5.6 80–120 b.i.d. 4.0 9.3 6.2 6.2
(n = 9) (n = 6) (n = 5)
Klinger and Laron 1995 9 0.5–14 0.2–11 −5.6 150–200 i.d 4.7 (1.3) 8.2 (0.8) 6 (1.3) 4.8 (1.3)*
(n = 15) (n = 15) (n = 6)
Guevarra-Aguirre et al 1997 15 3.1–17 4.5–9.3 120 b.i.d. 3.4 (1.4) 8.8 (11) 6.4 (1.1) 5.7 (1.4)
(n = 8) (n = 8)
Guevarra-Aguire et al 8 80 b.i.d. 3.0 (1.8) 9.1 (2.2) 5.6 (2.1)

Growth velocity values are mean (SD).

*The younger children had a growth velocity of 5.5 and 6.5 cm/year.

BA, bone age; b.i.d., twice daily; CA, chronological age; i.d., once daily; Ht SDS, height standard deviation score.

When the growth response to GH treatment in infants with IGHD was compared with that of IGF-1 in infants with LS we found that the infants with IGHD responded faster and better than those with LS. However, the small number of patients and the differences in growth retardation between the two groups makes it difficult to reach a conclusion.

Both hormones stimulated linear growth, but GH seemed more effective than IGF-1. One cause may be the greater growth deficit of the infants with LS than those with IGHD, an insufficient dose of IGF-1, or that there is a need for some GH to provide an adequate stem cell population of prechondrocytes to enable full expression of the growth promoting action of IGF-1, as postulated by Green and colleagues and Ohlson et al. All the above findings based on a few clinical studies with small groups of patients and a few experimental studies remain at present controversial. The crucial question is whether there are any, and if so, whether there are sufficient IGF-1 receptors in the “progenitor cartilage zone” of the epiphyseal cartilage (fig 4) to respond to endocrine and exogenous IGF-1. Using the mandibular condyle of 2 day old ICR mice, Maor et al showed that these condyles, which resemble the epiphyseal plates of the long bones, contain IGF-1 and high affinity IGF-1 receptors also in the chondroprogenitor cell layers, which enables them to respond to IGF-1 in vitro.

Sims et al, using mice with GH receptor KO showed that IGF-1 administration stimulates the growth (width) of the tibial growth plate and that IGF-1 has a GH independent effect on the growth plate. These findings are similar to those found when treating hypophysectomised rats with IGF-1.

In conclusion, IGF-1 is an important growth hormone, mediating the anabolic and linear growth promoting effect of pituitary GH protein. It has a GH independent growth stimulating effect, which with respect to cartilage cells is possibly optimised by the synergistic action with GH.

References

1. Tannenbaum GS, Ling N. The interrelationship of growth hormone (GH)-releasing factor and somatostatin in generation of the ultradian rhythm of GH secretion. Endocrinology 1984;115:1952–7. [PubMed[]
2. Laron Z. Growth hormone secretagogues: clinical experience and therapeutic potential. Drugs 1995;50:595–601. [PubMed[]
3. Ghigo E, Boghen M, Casanueva FF, et al., eds. Growth hormone secretagogues. Basic findings and clinical implications. Amsterdam: Elsevier, 1994.
4. Jaffe CA, Ho PJ, Demott-Friberg R, et al. Effects of a prolonged growth hormone (GH)-releasing peptide infusion on pulsatile GH secretion in normal men. J Clin Endocrinol Metab 1993;77:1641–7. [PubMed[]
5. Kojima M, Hosada H, Date Y, et al. Ghrelin is a growth-hormone-releasing acylated peptide from stomach. Nature 1999;402:656–60. [PubMed[]
6. Devesa J, Lima L, Tresquerres AF. Neuroendocrine control of growth hormone secretion in humans. Trends Endocrinol Metab 1992;3:175–83. [PubMed[]
7. Laron Z. The somatostatin-GHRH-GH-IGF-I axis. In: Merimee T, Laron Z, eds. Growth hormone, IGF-I and growth: new views of old concepts. Modern endocrinology and diabetes, Vol. 4. London-Tel Aviv: Freund Publishing House Ltd, 1996:5–10.
8. Salmon WD, Jr, Daughaday W. A hormonally controlled serum factor which stimulates sulfate incorporation by cartilage in vitro. J Lab Clin Med 1957;49:825–36. [PubMed[]
9. Froesch ER, Burgi H, Ramseier EB, et al. Antibody-suppressible and nonsuppressible insulin-like activities in human serum and their physiologic significance. An insulin assay with adipose tissue of increased precision and specificity. J Clin Invest 1963;42:1816–34. [PMC free article] [PubMed[]
10. Daughaday WH, Hall K, Raben MS, et al. Somatomedin: a proposed designation for the sulfation factor. Nature 1972;235:107. [PubMed[]
11. Rinderknecht E, Humbel RE. Polypeptides with non-suppressible insulin-like and cell-growth promoting activities in human serum: isolation, chemical characterization, and some biological properties of forms I and II. Proc Natl Acad Sci U S A 1976;73:2365–9. [PMC free article] [PubMed[]
12. Laron Z. Somatomedin-1 (recombinant insulin-like growth factor-I). Clinical pharmacology and potential treatment of endocrine and metabolic disorders. Biodrugs 1999;11:55–70. [PubMed[]
13. Blundell TL, Humbel RE. Hormone families: pancreatic hormones and homologous growth factors. Nature 1980;287:781–7. [PubMed[]
14. Rinderknecht E, Humbel RE. The amino acid sequence of human insulin like growth factor I and its structural homology, with proinsulin. J Biol Chem 1978;253:2769–76. [PubMed[]
15. Brissenden JE, Ullrich A, Francke U. Human chromosomal mapping of genes for insulin-like growth factors I and II and epidermal growth factor. Nature 1984;310:781–4. [PubMed[]
16. Mullis PE, Patel MS, Brickell PM, et al. Growth characteristics and response to growth hormone therapy in patients with hypochondroplasia: genetic linkage of the insulin-like growth factor I gene at chromosome 12q23 to the disease in a subgroup of these patients. Clin Endocrinol 1991;34:265–74. [PubMed[]
17. Rotwein P. Structure, evolution, expression and regulation of insulin-like growth factors I and II. Growth Factors 1991;5:3–18. [PubMed[]
18. Hwa V, Oh Y, Rosenfeld RG. The insulin-like growth factor binding protein (IGFBP) superfamily. Endocr Rev 1999;20:761–87 [PubMed[]
19. Lewitt MS, Saunders H, Phuyal JL, et al. Complex formation by human insulin-like growth factor-binding protein-3 and human acid-labile subunit in growth hormone-deficient rats. Endocrinology 1994;134:2402–9. [PubMed[]
20. Laron Z, Suikkairi AM, Klinger B, et al. Growth hormone and insulin-like growth factor regulate insulin-like growth factor-binding protein-1 in Laron type dwarfism, growth hormone deficiency and constitutional short stature. Acta Endocrinol 1992;127:351–8. [PubMed[]
21. Kanety H, Karasik A, Klinger B, et al. Long-term treatment of Laron type dwarfs with insulin-like growth factor I increases serum insulin-like growth factor-binding protein 3 in the absence of growth hormone activity. Acta Endocrinol 1993;128:144–9. [PubMed[]
22. Werner H. Molecular biology of the type I IGF receptor. In: Rosenfeld RG, Roberts CT, Jr, eds. The IGF system—molecular biology, physiology and clinical applications. Totowa, NJ: Humana Press, 1999:63–88.
23. Seino S, Seino M, Nishi S, et al. Structure of the human insulin receptor gene and characterization of its promoter. Proc Natl Acad Sci U S A 1989;86:114–18. [PMC free article] [PubMed[]
24. Bondy CA, Werner H, Roberts CT, Jr, et al. Cellular pattern of insulin-like growth factor I (IGF-I) and type I IGF receptor gene expression in early organogenesis: comparison with IGF-II gene expression. Mol Endocrinol 1990;4:1386–98. [PubMed[]
25. Kato H, Faria TN, Stannard B, et al. Essential role of tyrosine residues 1131, 1135, and 1136 of the insulin-like growth factor-I (IGF-I) receptor in IGF-I action. Mol Endocrinol 1994;8:40–50. [PubMed[]
26. LeRoith D, Werner H, Beitner-Johnson D, et al. Molecular and cellular aspects of the insulin-like growth factor I receptor. Endocr Rev 1995;16:143–63. [PubMed[]
27. Merimee T, Laron Z, eds. Growth hormone, IGF-I and growth: new views of old concepts. Modern endocrinology and diabetes, Vol. 4. London-Tel Aviv: Freund Publishing House Ltd, 1996.
28. D’Ercole AJ, Applewhite GT, Underwood LE. Evidence that somatomedin is synthesized by multiple tissues in the fetus. Dev Biol 1980;75:315–28 [PubMed[]
29. Nilsson A, Isgaard J, Lindhahl A, et al. Regulation by growth hormone of number of chondrocytes containing IGF-I in rat growth plate. Science 1986;233:571–4. [PubMed[]
30. Baserga R. The IGF-I receptor in cancer research. Exp Cell Res 1999;253:1–6. [PubMed[]
31. Rosenfeld RG, Roberts CT, Jr, eds. The IGF system—molecular biology, physiology and clinical applications. Totowa, NY: Humana Press, 1999.
32. Zapf J, Froesch ER. Insulin-like growth factor I actions on somatic growth. In: Kostyo J, ed. Handbook of physiology, Vol. V, Section 7. Philadelphia: American Physiological Society, 1999:663–99.
33. Laron Z, Pertzelan A, Mannheimer S. Genetic pituitary dwarfism with high serum concentration of growth hormone. A new inborn error of metabolism? Isr J Med Sci 1966;2:153–5. [PubMed[]
34. Laron Z, Pertzelan A, Karp M. Pituitary dwarfism with high serum levels of growth hormone. Isr J Med Sci 1968;4:883–94. [PubMed[]
35. Laron Z, Pertzelan A, Karp M, et al. Administration of growth hormone to patients with familial dwarfism with high plasma immunoreactive growth hormone. Measurement of sulfation factor, metabolic and linear growth responses. J Clin Endocrinol Metab 1971;33:332–42. [PubMed[]
36. Elders MJ, Garland JT, Daughaday WH, et al. Laron’s dwarfism: studies on the nature of the defect. J Pediatr 1973;83:253–63. [PubMed[]
37. Laron Z, Parks JS, eds. Lessons from Laron syndrome (LS) 1966–1992. A model of GH and IGF-I action and interaction. Pediatric and Adolescent Endocrinology 1993;24:1–367. []
38. Godowski PJ, Leung DW, Meacham LR, et al. Characterization of the human growth hormone receptor gene and demonstration of a partial gene deletion in 2 patients with Laron type dwarfism. Proc Natl Acad Sci U S A 1989;86:8083–7. [PMC free article] [PubMed[]
39. Amselem S, Duquesnoy P, Attree O, et al. Laron dwarfism and mutations of the growth hormone-receptor gene. N Engl J Med 1989;321:989–95. [PubMed[]
40. Laron Z. Laron syndrome—primary growth hormone resistance. In: Jameson JL, ed. Hormone resistance syndromes. Contemporary endocrinology, Vol. 2. Totowa, NJ: Humana Press, 1999:17–37.
41. Laron Z. Laron type dwarfism (hereditary somatomedin deficiency): a review. In: Frick P, Von Harnack GA, Kochsiek GA, et al, eds. Advances in internal medicine and pediatrics. Berlin-Heidelberg: Springer-Verlag, 1984:117–50. [PubMed]
42. Feinberg MS, Scheinowitz M, Laron Z. Echocardiographic dimensions and function in adults with primary growth hormone resistance (Laron syndrome). Am J Cardiol 2000;85:209–13. [PubMed[]
43. Brat O, Ziv I, Klinger B, et al. Muscle force and endurance in untreated and human growth hormone or insulin-like growth factor-I-treated patients with growth hormone deficiency or Laron syndrome. Horm Res 1997;47:45–8. [PubMed[]
44. Lurie R, Ben-Amitai D, Laron Z. Impaired hair growth and structural defects in patients with Laron syndrome (primary IGF-I deficiency) [abstract]. Horm Res 2001 [In press.]
45. Gluckman PD, Gunn AJ, Wray A, et al. Congenital idiopathic growth hormone deficiency associated with prenatal and early postnatal growth failure. J Pediatr 1992;121:920–3. [PubMed[]
46. Woods KA, Camacho-Hubner C, Savage MO, et al. Intrauterine growth retardation and postnatal growth failure associated with deletion of the insulin-like growth factor I gene. N Engl J Med 1996;335:1363–7. [PubMed[]
47. Zhou Y, Xu BC, Maheshwari HG, et al. A mammalian model for Laron syndrome produced by targeted disruption of the mouse growth hormone receptor/binding protein gene (the Laron mouse). Proc Natl Acad Sci U S A 1997;94:13215–20. [PMC free article] [PubMed[]
48. Sjogren K, Bohlooly YM, Olsson B, et al. Disproportional skeletal growth and markedly decreased bone mineral content in growth hormone receptor –/– mice. Biochem Biophys Res Commun 2000;267:603–8. [PubMed[]
49. Accili D, Nakae J, Kim JJ, et al. Targeted gene mutations define the roles of insulin and IGF-I receptors in mouse embryonic development. J Pediatr Endocrinol Metab 1999;12:475–85. [PubMed[]
50. Holzenberger M, Leneuve P, Hamard G, et al. A targeted partial invalidation of the insulin-like growth factor-I receptor gene in mice causes a postnatal growth deficit. Endocrinology 2000;141:2557–66. [PubMed[]
51. Schoenle E, Zapf J, Humbel RE, et al. Insulin-like growth factor I stimulates growth in hypophysectomized rats. Nature 1982;296:252–3. [PubMed[]
52. Guler H-P, Zapf J, Scheiwiller E, et al. Recombinant human insulin-like growth factor I stimulates growth and has distinct effects on organ size in hypophysectomized rats. Proc Natl Acad Sci U S A 1988;85:4889–93. [PMC free article] [PubMed[]
53. Niwa M, Sato Y, Saito Y, et al. Chemical synthesis, cloning and expression of genes for human somatomedin C (insulin like growth factor I) and 59Val somatomedin C. Ann N Y Acad Sci 1986;469:31–52. [PubMed[]
54. Guler HP, Zapf J, Froesch ER. Short term metabolic effects of recombinant human insulin like growth factor in healthy adults. N Engl J Med 1987;317:137–40. [PubMed[]
55. Laron Z, Klinger B, Silbergeld A, et al. Intravenous administration of recombinant IGF-I lowers serum GHRH and TSH. Acta Endocrinol 1990;123:378–82. [PubMed[]
56. Klinger B, Garty M, Silbergeld A, et al. Elimination characteristics of intravenously administered rIGF-I in Laron type dwarfs (LTD). Dev Pharmacol Ther 1990;15:196–9. [PubMed[]
57. Laron Z, Klinger B, Jensen LT, et al. Biochemical and hormonal changes induced by one week of administration of rIGF-I to patients with Laron type dwarfism. Clin Endocrinol 1991;35:145–50. [PubMed[]
58. Klinger B, Jensen LT, Silbergeld A, et al. Insulin-like growth factor-I raises serum procollagen levels in children and adults with Laron syndrome. Clin Endocrinol 1996;45:423–9. [PubMed[]
59. Underwood LE, Backeljauw P. IGFs: function and clinical importance of therapy with recombinant human insulin-like growth factor I in children with insensitivity to growth hormone and in catabolic conditions. J Intern Med 1993;234:571–7. [PubMed[]
60. Ranke MB, Savage MO, Chatelain PG, et al. Long-term treatment of growth hormone insensitivity syndrome with IGF-I. Horm Res 1999;51:128–34. [PubMed[]
61. Ranke MB, Savage MO, Chatelain PG, et al. Insulin-like growth factor (IGF-I) improves height in growth hormone insensitivity: two years results. Horm Res 1995;44:253–64. [PubMed[]
62. Backeljauw PF, Underwood LE, The GHIS Collaborative Group. Prolonged treatment with recombinant insulin-like growth factor I in children with growth hormone insensitivity syndrome—a clinical research center study. J Clin Endocrinol Metab 1996;81:3312–17. [PubMed[]
63. Klinger B, Laron Z. Three year IGF-I treatment of children with Laron syndrome. J Pediatr Endocrinol Metab 1995;8:149–58. [PubMed[]
64. Guevara-Aguirre J, Rosenbloom AL, Vasconez O, et al. Two year treatment of growth hormone (GH) receptor deficiency with recombinant insulin-like growth factor-I in 22 children: comparison of two dosage levels and to GH treated GH deficiency. J Clin Endocrinol Metab 1997;82:629–33. [PubMed[]
65. Laron Z, Lilos P, Klinger B. Growth curves for Laron syndrome. Arch Dis Child 1993;68:768–70. [PMC free article] [PubMed[]
66. Krzisnik C, Battelino T. Five year treatment with IGF-I of a patient with Laron syndrome in Slovenia (a follow-up report). J Pediatr Endocrinol Metab 1997;10:443–7. [PubMed[]
67. Laron Z, Klinger B. Comparison of the growth-promoting effects of insulin-like growth factor I and growth hormone in the early years of life. Acta Paediatr 2000;89:38–41. [PubMed[]
68. Green H, Morikawa M, Nixon T. A dual effector theory of growth hormone action. Differentiation 1985;29:195–8. [PubMed[]
69. Ohlson C, Bengtsson BA, Isaksson OG, et al. Growth hormone and bone. Endocr Rev 1998;19:55–79. [PubMed[]
70. Maor G, Laron Z, Eshet R, et al. The early postnatal development of the murine mandibular condyle is regulated by endogenous insulin-like growth factor-I. J Endocrinol 1993;137:21–6. [PubMed[]
71. Sims NA, Clement-Lacroix P, Da Ponte F, et al. Bone homeostatis in growth hormone receptor-null mice is restored by IGF-I but independent of Stat5. J Clin Invest 2001;106:1095–103. [PMC free article] [PubMed[]

❓Can You Help?

Can someone please offer help, ive been suffering for a year and just got blood results today with a high cortisol reading. My doctor said that my contraceptive pill could have caused this, however, I am not on the regular pill but on the POP progesteron only pill.

Is anyone aware of if this raises cortisol levels the same way the regular combined pill does?

Any help would be so very much appreciated!

 

Please respond here, on the message boards, or in the original post.

 

Thanks!

❓Guest Question: Legal Assistance for Cushing’s Patients

 

If you can help, please respond here or on the Message Boards.  Thanks!

I believe I need legal assistance related to i humane treatment by city and/or county officials. I can explain further, if need be, once I find out if it’s even possible to get help. And I certainly cannot afford to pay an attorney, since my income is SSD (Disability), which is low and fixed, which has been the case since Cushing’s reared it’s remorseless, destructive head in 2008. Is there any legal assistance fund set up for Cushing’s patients?

 

❓Can You Help?

I think I have Cushing’s I have about 10 symptoms…my cortisol levels came out high with a 24 hour urine hormone panel but my endocrinologist did not even mention it. At the time when I had the test done, (March 2020)I had no idea what cortisol was. I just figured and trusted my endocrinologist would prescribe me with whatever hormones and or treatment I needed and would have me take whatever tests he order. Anyhow, in a range from 1-10 for bedtime cortisol, my result was 27! Cortisol metabolites, range from 1160-2183, my result was 5370!!!

The only reason I started to do more research on cortisol is because just a few weeks ago I started experiencing severe chest pain from the moment I wake up and any little thing stresses me out and gives me anxiety and I feel like I’m gonna have a heart attack any moment!  So I looked back at my paperwork and noticed these really elevated cortisol levels. But my endocrinologist never mention them… Why? This is how I found this disease,  I have so many symptoms of Cushing’s disease, And it is not a result of exogenous stuff causing cortisol levels to rise. I don’t take any medication whatsoever and was not taking any medication at that time or for the past year. All I have taken for the past year is what he prescribed, thyroid medication and progesterone. Someone please tell me if these levels are of concern from your perspective.

Please respond here or on the message boards.

Thanks!

🥸 Cushie 12-Step Program

I “acquired” this from another site and changed the names to protect the innocent…

As you know many of us Cushies have had or have an addiction to Googling.

I suggest anyone who feels compelled to google symptoms go to the message boards to ask for support instead of typing these or any words such as “buffalo hump” in the google search engine. When this is done all roads lead to one thing…… You Eat Too Much!; You’re Depressed!

So, anyone who is about to hit enter on their computer which feeds their Google addiction…. go to the message boards to ask for help. One of the other Cushies who have achieved “Google sobriety” will help you down of the ledge.

1. Admit for now that you are powerless over your urge to Google.
2. Believe that a power greater than you (that would be other Cushies) can help you off that ledge
3. Decide to turn your “fingers” over to a higher power as you understand it.
4. Make a searching and fearless inventory of what you hope to gain from googling.
5. Admit to yourself and to another human being the exact nature of your addiction to Google.
6. Allow other Cushies to assist you when you are so scared you are thinking about googling symptoms.
7. Humbly ask for Xanax, Klonopin or Cortef in order to calm yourself from googling symptoms
8. Make a list of all the diseases you think you have or have had and survived and have a burning ceremony and then…. take a nap.
9. Cite all Google sites you have searched diseases on and delete them from your favorites/history.
10. When you start thinking….STOP….. do something else, like take an inventory of your test results.
11. Seek through prayer and/or meditation to improve your thought process. Do not travel to “OMG’ or “What if” land (this is a serious suggestion).
12. Having had a spiritual awakening as a result of these steps, carry this message to all your Cushie friends and anyone else you know who has a Google addiction.

13. Now I know there isn’t a 13th step, however, if you have noticed you are drinking too much wine or taking too many pills, please remember there are other 12 step programs for that, lol…

So, what about it – what are *your* suggestions to cure Google Addiction?