Serum soluble interleukin-2 receptors as an index of the biological activity of thyroid hormones in hyperthyroidism

Exposure to the UV Filter Octyl Methoxy Cinnamate in the Postnatal Period Induces Thyroid Dysregulation and Perturbs the Immune System of Mice

Evidence demonstrates the bidirectional communication and regulation between the neuroendocrine and immune systems. Thyroid hormones play key roles in nervous system development and can exert influence on various immune cells contributing to pathophysiological conditions. Octyl methoxycinnamate (OMC) is one of the most commonly used UV filters, and in vitro and in vivo studies have found thyroid disrupting effects. The present study assessed whether OMC administration in mice dams during the lactational period can cause thyroid disruption and generate immunologic alterations in the offspring. Indirect exposure to the OMC (1,000 mg/kg) in the lactational period affected neurodevelopment parameters, such as delayed eye-opening and weight gain in mice of both sexes, and these alterations are corroborated by the decrease in the T4 levels present in the pups' blood. No significant changes were observed in the thymus of these pups, but the number of lymphocytes increased in the spleen of the animals exposed to OMC, similar to the animals treated with propyl-thiouracil (PTU), a well-known thyroid disruptor. OMC modulated the percentage of leukocyte populations in peripheral blood, and the number of circulating polymorphonuclear cells increased two-fold. In vitro, OMC exhibited an inhibitory effect on splenocyte proliferation and IL-2 production induced by anti-CD3 antibody; however, this effect was reversed with the addition of T4 in the cell culture. In summary, the results of the present study demonstrate the influence of OMC on thyroid dysregulation and its impact on the modulation of the immune system in mice pups.

Increased soluble IL-2 receptor levels in serum from a patient with painless thyroiditis

Context

Serum concentration of soluble interleukin-2 receptor (sIL-2R) has been established as a reliable marker of T-lymphocyte activation. However, there have been no reports describing the relationship between serum sIL-2R and painless thyroiditis.

Objective

We report a case of a 76-yr-old female with a significant and temporary increase of sIL-2R concomitant with painless thyroiditis.

Case illustration

The patient was diagnosed with malignant lymphoma at the age of 73. After 6 cycles of CHOP-R complete remission was induced and no recurrence was observed up to 3.5 years. At 76 years of age, she exhibited hyperthyroidism and was diagnosed with painless thyroiditis based upon US examination and ^99mTc-Thyroid scintigraphy. Her AST and ALT were mildly elevated, and her serum level of sIL-2R increased up to 2230 U/mL from the approximately 540 U/mL, which had been stable for 3 years before.

These abnormal data normalized without requiring any treatment. The time-course of the reduction in sIL-2R did not correlate with FT4 or FT3, but was very similar to that of AST and ALT.

Conclusion

There was no evidence of relapse of the malignant lymphoma. We conclude that the increase of sIL-2R was associated with painless thyroiditis. Considering the similar time-course between the reduction of serum sIL-2R and those of AST and ALT, which are often accompanied by autoimmune processes in painless thyroiditis during the development of hyperthyroidism, it was suggested that the increase of serum sIL-2R in this case resulted from activation of an autoimmune process.

On the pulmonary toxicity of oxygen. 4. The thyroid arena

Normally developed thyroid function is critical to the transition from fetal to neonatal life with the onset of independent thermoregulation, the most conspicuous of the many ways in which thyroid secretions act throughout the body. A role for thyroid secretions in growth and maturation of the lungs as part of the preparation for the onset of breathing has been recognized for some time but how this contributes to tissue and cell processes and defenses under the duress of respiratory distress has not been well examined. Extensive archival autopsy material was searched for thyroid and adrenal weights, first by gestational age, and then for changes during the first hours after birth as ratios to body weight. After a gestational age of 22 weeks the fetal thyroid and adrenal glands at autopsy in those with hyaline membrane disease are persistently half the size of those in "normal" infants dying with other disorders. When the thyroid is examined shortly after birth it reveals a post natal loss of mass per body weight of similar orders of magnitude which does not occur in the control group. A clinical sample of premature infants with (12) and without (14) hyaline membrane disease was tested for T(4), TSH, TBG, and total serum protein. The results also demonstrate a special subset with lower birth weights at the same gestational age, and lower serum T(4) and total serum protein. Ventilatory distress in newborn rabbits was induced by bilateral cervical vagotomy at 24 h post natal following earlier injection of thyroxine (T(4)) or thyroid stimulating hormone (TSH) and comparisons were made with untreated animals and by dose. Early life thyroidectomy was performed followed by exposure to either air or 100% oxygen. A final experiment in air was vagotomy after thyroidectomy. Composite analysis of these methods indicates that thyroid factors are both operative and important in the newborn animal with ventilatory distress. This work and the archival data indicate those infants destined to develop hyaline membrane disease through respiratory distress are a distinct developmental and clinical subset with the point of departure from otherwise normal development and maturation in the second or early third trimester. This interval is known to be a period of marked variation in the overview indicators of fetal progress through gestational time. The initiating factor or circumstance which then separates this special subset from normal future development is placed by these observations firmly into the period when human fetal TSH dramatically rises 7-fold (17.5-25.5 weeks) followed by a lesser 3 to 4-fold increase in T(4) which is extended into the early third trimester. The earlier part of this interval is characterized by the thyrotrophic action of chorionic gonadotropin (hCG). The possibility that abnormalities in the intrauterine environment secondary to maternal infection play a role within this time frame is indicated by the demonstration that interleukin-2 (IL-2) induces an anterior pituitary release of TSH. Since IL-2 has this property and is not an acute phase cytokine, some form of chronic infection or an immunopathic process seems more likely as a possible active factor in pathogenesis.

Serum levels of interleukin-12 in Graves' disease and their dynamic changes after surgery

PURPOSE

To investigate the role of interleukin-12 (IL-12) in Graves' disease, we measured the pre- and postoperative levels of serum IL-12 in patients undergoing surgery for Graves' disease.

METHODS

The subjects of this study were 73 patients with Graves' disease, admitted for surgical treatment after taking antithyroid drugs for various durations. We collected blood from 11 of these patients, 1, 3, and 6 months postoperatively, to measure the serum IL-12 levels using a Human IL-12 +p40 Immunoassay Kit.

RESULTS

The preoperative levels of serum IL-12 were higher in patients with Graves' disease than in healthy controls. Based on the preoperative data, there was a significant relationship between the levels of serum IL-12 and free T3. An analysis of the postoperative time course of these 11 patients showed that the levels of serum IL-12 decreased gradually from 1 month to 6 months, postoperatively. There was also a significant correlation between the levels of serum IL-12 and soluble IL-2R, and a significant negative correlation between the levels of serum IL-12 and thyroid-stimulating hormone receptor antibody.

CONCLUSION

Measurement of the levels of serum IL-12 may be a valuable immunological marker in the time course of treatment for Graves' disease.

Sex hormone binding globulins and atherosclerotic risk in systemic lupus

Sex hormone binding globulin (SHBG) is a transport protein in human plasma which regulates the bioavailability of sex hormones, mediates membrane receptor signaling and may affect inflammatory processes, suggesting a regulatory role for this protein in the prevention of atherosclerosis. The current report summarizes literature implicating several members of the SHBG family in the regulation of hormonal and inflammatory processes which may be pertinent to the accelerated atherosclerosis seen in systemic lupus.

Serum cytokine levels in autoimmune and non-autoimmune hyperthyroid states

Although the role of interleukin-2 (IL-2) and interferon gamma (gammaIFN) is still poorly understood in hyperthyroid diseases, it is reasonable to assume that these cytokines may be present at higher levels in Graves' disease (GD) than in other primarily non-autoimmune thyroid diseases. In order to look for an easy method to distinguish GD from primarily non-autoimmune causes of hyperthyroidism, we compared 13 healthy individuals with 21 treated and untreated hyperthyroid GD patients and with 19 patients with hyperthyroidism due to other etiologies: 7 cases of multinodular goiter, 5 cases of excessive hormone replacement and 7 cases of amiodarone-associated hyperthyroidism. All patients presented low TSH levels and a dubious clinical thyroid state. We found a good correlation between TSH and serum IL-2 levels (r = 0.56; P<0.01). Serum IL-2 (P<0.01) and gammaIFN (P<0.01) levels were lower in the hyperthyroid group of patients than in control subjects, suggesting a depressed TH1 pattern in the T-cell subset of hyperthyroid patients. GD had normal IL-2 levels, while patients with other forms of thyrotoxicosis presented decreased IL-2 levels (P<0.05). There was no difference between treated and untreated GD patients. We suggest that the direct measurement of serum IL-2 level may help to confirm hyperthyroidism caused by GD.

Evaluation of the adequacy of levothyroxine replacement therapy in patients with central hypothyroidism

As there are few data on the evaluation of the adequacy of levothyroxine (L-T4) therapy in patients with central hypothyroidism (CH), a prospective study was performed to assess the accuracy of various parameters in the follow-up of 37 CH patients. Total and free thyroid hormones, TSH, and a series of clinical and biochemical indexes of peripheral thyroid hormone action have been evaluated off and on L-T4 therapy. Samples were taken before the daily administration of L-T4. In all patients off therapy, clinical hypothyroidism and low levels of free T4 (FT4) were observed, whereas values of FT3, total T4, and total T3 were below the normal range in 73%, 57%, and 19% of cases, respectively. Most of the indexes of thyroid hormone action were significantly modified after L-T4 withdrawal and exhibited significant correlation with free thyroid hormone levels. During L-T4 replacement therapy, 32 patients had circulating levels of FT4 and FT3 and indexes within the normal range with a mean L-T4 daily dose of 1.5 +/- 0.3 microg/kg BW. Despite normal serum FT4, 3 patients had borderline high values of FT3 and a clear elevation of serum-soluble interleukin-2 receptor concentrations, suggesting overtreatment. Low or borderline low FT4/FT3 levels indicated undertreatment in 2 patients. The clinical parameters lack the required specificity for the diagnosis or follow-up of CH patients. The L-T4 daily dose should be established, taking into account the weight, the age, and the presence of other hormone deficiencies or pharmacological treatment of CH patients. In conclusion, our results indicate that the diagnosis of CH is reached at best by measuring TSH and FT4 concentrations. In the evaluation of the adequacy of L-T4 replacement therapy, both FT4 and FT3 serum levels together with some biochemical indexes of thyroid hormone action are all necessary to a more accurate disclosure of over- or undertreated patients.

Cytokines serum levels as the markers of thyroid activation in Graves' disease

In order to examine which cytokine could be used as a marker of the biological effect of thyroid hormones or anti-thyroid antibodies in Graves' disease (GD) patients, we simultaneously evaluated the concentrations of TSH, free thyroid hormones (fT3 and fT4), anti-thyroid antibodies (anti-TPO and anti-TG) and a group of cytokines: interleukin-2 (IL-2), tumour necrosis factor alpha (TNFalpha), interleukin-6 (IL-6) and their soluble receptors (sIL-2R, sTNFalphaR, sIL-6R) as well as interleukin-10 (IL-10) in eight GD females and nine normal controls. We found that serum sIL-2R concentrations of GD patients had only the tendency to be higher versus controls, but strong positive correlations between fT3 and fT4 and sIL-2R in peripheral blood of GD subjects were revealed. We showed that sIL-2R was the best cytokine marker, showing very good correlation with the endocrine status of GD patients.