Alteration of Serum Proteome in Levo-Thyroxine-Euthyroid Thyroidectomized Patients

Area of Science:

• Endocrinology
• Proteomics
• Molecular Biology

Background:

• Levothyroxine (LT4) is the standard treatment for hypothyroidism post-thyroidectomy.
• Some patients experience hypothyroid symptoms despite normal thyroid hormone levels and lower FT3 post-surgery.
• Tissue hypothyroidism is hypothesized as a cause for persistent symptoms.

Purpose of the Study:

• To investigate the serum protein profiles of thyroidectomized patients with reduced post-surgical FT3 levels.
• To identify potential biomarkers reflecting tissue hypothyroidism.
• To compare these profiles with patients maintaining stable FT3 and healthy controls.

Main Methods:

• Preliminary proteomic analysis of serum samples.
• Comparison of protein profiles between three groups: reduced post-surgical FT3, stable FT3, and healthy controls.
• Enrichment analysis to identify differentially expressed proteins and pathways.

Main Results:

• Significant differences in serum protein profiles were observed across the groups.
• Proteins involved in coagulation, complement system activation, and lipoprotein remodeling were differentially abundant.
• Specific proteins like PLMN, A1AT, CFAH, CFAB, C1Qb, C1S, APOAI, and APOAIV showed altered levels.

Conclusions:

• LT4 therapy may normalize biochemical thyroid status but not necessarily tissue euthyroidism.
• Altered serum protein profiles, particularly those related to inflammation and coagulation, may indicate persistent tissue hypothyroidism.
• Proteomics offers a potential avenue for identifying patients with suboptimal LT4 treatment response.