Relationships Between Thyroid Hormones, Insulin-Like Growth Factor-1 & Antioxidant Levels in Hypothalamic Amenorrhea & on Bone Metabolism

[helvella]

Another paper which points at low T3 affecting bone mass density. The context might be particular, but the connection seems just what we have been seeing elsewhere.

Horm Metab Res. 2019 Mar 7. doi: 10.1055/a-0859-4285. [Epub ahead of print]

Relationships Between Thyroid Hormones, Insulin-Like Growth Factor-1 and Antioxidant Levels in Hypothalamic Amenorrhea and Impact on Bone Metabolism.

Mancini A1,2, Vergani E1,2, Bruno C1,2, Barini A3,4, Silvestrini A3,4, Meucci E3,4, Messana C5,6, Romualdi D5,6, Apa R5,6, Lanzone A5,6.

Author information

1 UOC Endocrinologia e Diabetologia, Fondazione Policlinico Universitario A, Gemelli IRCCS, Rome, Italy.

2 Istituto di Patologia Speciale Medica e Semeiotica Medica, Università Cattolica del Sacro Cuore, Rome, Italy.

3 Fondazione Policlinico Universitario A, Gemelli IRCCS, Rome, Italy.

4 Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Rome, Italy.

5 UOC Ostetricia e Patologia Ostetrica, Fondazione Policlinico Universitario A, Gemelli IRCCS, Rome, Italy.

6 Istituto di Clinica Ostetrico e Ginecologica, Università Cattolica del Sacro Cuore, Rome, Italy.

Abstract

Reduced bone mineral density (BMD) in Functional Hypothalamic Amenorrhea (FHA) is mainly related to hypoestrogenism, but other hormonal derangement (reduced conversion of T4-T3 and GH resistance) can play a role. These hormones are involved in antioxidant systems regulation. We evaluated the impact of hormonal alterations, with special focus on low T3 and IGF-1 levels, on antioxidant systems as a link with osteoporosis in FHA. Forty-three FHA patients, 15-34 years, with BMI range 17.3-23.4 kg/m2, were divided in 2 groups according to fT3 levels; group A (n=22), low fT3 (<2.4 pg/ml) and group B (n=21), normal fT3 (≥ 2.4 pg/ml). We evaluated hormonal parameters (fT3, fT4, TSH, IGF-1, FSH, LH, estradiol, DHEAS, testosterone, cortisol), bone metabolism (calcium, phosphorus, 25-OH Vitamin D, PTH, β-crosslaps, bone alkaline phosphatase) and total antioxidant capacity (TAC), expressed as LAG (latency time in radical species appearance using spectrophotometric method). BMD was assessed by DEXA. Group A patients exhibited significantly lower levels of IGF-1 (159.76±14.79 vs. 220.05±15.25 ng/ml) and osteocalcin (17.51±1.14 vs. 21.49±1.56 ng/ml); LAG values were significantly higher in A (66.33±1.74 s) vs. B (54.62±1.74 s). A significant direct correlation was found between both IGF-1 and fT3 with osteocalcin (r²=0.22, p=0.0049 and r²=0.34, p=0.0001, respectively). No difference in LAG between groups according to IGF-1 were found. These data show a correlation between altered bone turnover and low fT3, which is highly prevalent in FHA. Low fT3 levels may contribute to reduced BMD. Oxidative stress could be the link underlying different bone turnover pattern and endocrine dysfunction in FHA.

© Georg Thieme Verlag KG Stuttgart · New York.

PMID: 30847871

DOI: 10.1055/a-0859-4285

ncbi.nlm.nih.gov/pubmed/308...

[Heloise]

The evidence keeps mounting. When will they listen? It's still good for US to know if not them. Thanks, Rod.

[Hay2016]

Thanks. Another for my file. Although my t3 is in range but never higher than 50% which the Endos say is perfect.

[crimple]

Thanks for posting Helvella. One to keep handy if Endo kicks up about my TSH 0.01 whilst taking some T3 with my T4, which are both in range

[LindaC]

Thank you so much - an endo [veritably advertising himself professionally as dealing with 'outlier-type' patients, which I thought I was until I recently got my medical records - depicting that I'd been hypothyroid since Sept 2003, similar result in 2008 - by which time I was so ill, like those old late 1880's BEFORE treatment photos. Finally diagnosed by Dr S in Feb 2010 and incidentally [seeking advice on supplement reduction] by Dr P in May 2010.

This endo, 2015, decided to test my beta crosslaps.... to dissuade me from using T3 [long since advised by Dr P - I was already on Armour T via Dr S, that being sanctioned by GP, and paid for by NHS]. Endos mention of bones, had me go to GP and ask for a DEXA scan - came back fine - then the beta crosslaps results were 'not made available to me', despite my having asked for copies of ALL results in advance of appointment.

Finally I prized a copy from GP which put me at such a high level of risk, indicative of Paget's Disease of the bone [my G'father died with], thyrotoxicosis [I'd asked to see endo because I was FREEZING cold, punch drunk - hardly signs of too much T3!] and some other serious conditions were on that list. Oh, their ranges... 0.5 top of this range, mine was 1.35 yet info kept from me. Then, even when I asked to be retested, I was ignored but had the hospital 'Complaints Dept' on to me... I said, "I'm not making a complaint, I'm ill not dim".

I FORGOT THE BEST BIT - HE UN_DIAGNOSED ME AS NEVER HAVING BEEN HYPOTHYROID!

Clearly I'll be taking this up - not as a complaint - but as a publication of... I still have no idea re my bones, but have had recent issues and I'm going for a lumbar [only] MRI tomorrow - at my insistence. My cervical neck - moderate to marked deterioration...

[kissemiss]

Well isn't that interesting to see how t3 plays such an important part in this research on bone density. Helvella thank you so much for this fascinating contribution.