Thyroid hormone level is associated with motor symptoms in de novo Parkinson’s disease

Abstract

Sympathetic denervation has been observed not only in the myocardium but also in the thyroid of patients with Parkinson's disease (PD). We investigated whether sympathetic denervation as indicated by decreased cardiac (123)I-meta-iodobenzylguanidine uptake is associated with the levels of thyroid hormones and whether the levels of thyroid hormones affect clinical manifestations in patients with PD. The subjects were 75 patients with de novo PD and 20 age-matched healthy controls. We examined the levels of thyroid-stimulating hormone, free triiodothyronine, and free thyroxine, and evaluated the associations of these levels with cardiac (123)I-meta-iodobenzylguanidine uptake and motor symptoms. The results showed that the free triiodothyronine level was below the normal range in 29 patients (approximately 40 %) and was significantly lower in the patients with PD than in the controls. The decreased free triiodothyronine level was associated with akinetic-rigid motor subtype and washout ratio of cardiac (123)I-meta-iodobenzylguanidine scintigraphy. The free triiodothyronine level negatively correlated with disease severity. Thyroid-stimulating hormone level was within normal range. However, its level was lower in patients with tremor-dominant type or mixed type than in those with akinetic-rigid type. All correlations of these variables with the levels of thyroid hormones remained statistically significant on multiple regression analysis. Our results suggest that the thyroid hormone level, especially the free triiodothyronine level, is closely related to motor symptoms in patients with de novo PD. Further studies are needed to clarify whether the decreased hormone levels have functional roles in motor and non-motor symptoms.

Embelin and Levodopa Combination Therapy Mitigates Parkinson's Disease Complications in Mice

“…Also, embelin has considerably shown inhibition of lipid peroxidation and up-regulation of Mn-superoxide dismutase levels. 46 In earlier work Umehara et al 47 reported significantly lower levels of T3 in PD patients with notable motor symptoms which could be associated with the present findings. However, there is a limited information available from patients with aggravated parkinsonism due to hypothyroidism.…”

“…51 Even though there are still many debates regarding the connection between thyroid function and neurodegenerative disease, it seems that the free T3 levels were found to be lower in PD patients particularly with akinetic-rigid motor subtype, whereas TSH levels were lesser in patients with tremor-dominant type or mixed type, signifying a relation of the thyroid hormone level with PD motor signs. 47 Unfortunately we lack convincing studies from PD mice on TSH levels.…”

Selenotranscriptomic Analyses Identify Signature Selenoproteins in Brain Regions in a Mouse Model of Parkinson’s Disease

“…In contrast to Gpx family, the Dio1-3 mRNA levels are not significantly affected in the brain regions of PD mice. Although hypothyroidism and abnormal thyroid hormone levels are sometimes reported in PD patients [ 26 , 27 ], our results suggest little or no role of Dios in the PD brain. This is indeed not surprising, considering the nature of Dio family members in catalyzing deiodination of thyroid hormone and their relatively low abundance in the brain.…”

Structural binding site comparisons reveal Crizotinib as a novel LRRK2 inhibitor

“…Liothyronine is a synthetic form of the thyroid hormone triiodothyronine that is used for hypothyroidism [48] . It has been shown that there is an association of low thyroid hormone levels with motor symptoms in Parkinson’s disease [49] . Efavirenz is a non-nucleoside inhibitor of reverse transcriptases and is used for the treatment and prevention of HIV/AIDS [50] .…”