Comparing Oxidative Stress Status Among Iranian Males and Females with Malignant and Non-malignant Thyroid Nodules

Changes in biomarkers of the redox status in whole blood and red blood cell lysates in canine hypothyroidism

Hypothyroidism is the most commonly diagnosed endocrine disease in dogs. The objective of this study was to evaluate the changes in the redox status in canine hypothyroidism using whole blood (WB) and red blood cell (RBCs) lysates. For this purpose, a panel of five antioxidants and five oxidants biomarkers was measured in WB and RBCs lysates of 30 dogs with hypothyroidism, 26 dogs with non-thyroidal illnesses and 15 healthy dogs. The antioxidants measured were cupric reducing antioxidant capacity (CUPRAC), ferric reducing ability of plasma (FRAP), Trolox equivalent antioxidant capacity (TEAC), thiol and paraoxonase type-1 (PON-1). Oxidants measured include the total oxidant status (TOS), peroxide-activity (POX-Act), reactive oxygen-derived metabolites (d-ROMs), advanced oxidation protein products (AOPP) and thiobarbituric acid reactive substances (TBARS). WB showed a significant decrease of the antioxidants CUPRAC, TEAC and thiol, and also an increase in TBARS and a decrease in AOPP in dogs with hypothyroidism compared to healthy dogs. Meanwhile, RBCs lysates showed a significant increase in FRAP and PON-1 in dogs with hypothyroidism. The changes in the redox biomarkers in this study show that WB in canine hypothyroidism had a higher number of changes in biomarkers of the redox status than RBCs lysates, making it a promising sample type for the evaluation of the redox status in this disease. In addition, WB is easier and simpler to process than RBCs lysates and unlike serum, it does not have any hemolysis interference.

From balance to imbalance: disruption of plasma glutathione concentration in micropapillary thyroid carcinoma

BACKGROUND

Despite the presence of evidence that establishes a strong correlation between oxidative stress and thyroid cancer, there exists a scarcity of research that investigates the specific role of glutathione as an important antioxidant in this particular context. The objective of this study was to assess the altered balance of oxidative stress in cases of thyroid cancer, which includes both papillary thyroid carcinoma (PTC) and micro PTC (mPTC), by examining and comparing the total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), reduced glutathione (GSH), oxidized glutathione (GSSG), and GSSG/GSH ratio with those of individuals diagnosed with multinodular goiter (MNG) as well as Healthy subjects.

MATERIALS AND METHODS

Plasma samples were collected from 92 patients (23 mPTC, 23 PTC, 23 MNG, 23 Healthy). The levels of TAC, TOS, GSH, and GSSG were measured using a commercial assay kits, and the OSI and GSSG/GSH ratio were calculated for each sample. Statistical analyses were performed to compare the oxidative stress between the groups.

RESULTS

The plasma levels of TOS were significantly higher in the mPTC, PTC, and MNG groups compared to the Healthy individuals (p < 0.05). The OSI in the mPTC and PTC groups showed a significant increase compared to the Healthy group (p < 0.05). The levels of GSH in mPTC and PTC were markedly lower compared to the Healthy subjects (p < 0.01). Interestingly, the concentration of GSH in mPTC was found to be considerably lower than in PTC and MNG patients (p < 0.01).

CONCLUSION

These findings indicate that GSH may be a useful biomarker for evaluating oxidative stress and antioxidant system status in patients with PTC, especially mPTC. Low levels of GSH may indicate increased levels of oxidative stress, which may contribute to the development and progression of mPTC to PTC.

Possible Markers for Distinguishing benign and Malignant Thyroid Tumors and Predicting Malignancy in Patients with Genetic Predisposition to Cancer

BACKGROUND

We hypothesized that mutations in several genes disrupt oxidative metabolism, increasing the risk of developing tumors and their malignancy in patients with a family predisposition to cancer. The purpose of our study was to assess the characteristics of oxidative metabolism in patients with malignant and benign tumor with and without a family history of cancer and identify the marker predicting the likelihood of malignancy.

METHODS

We conducted a study on patients with thyroid pathology (thyrotoxicosis, benign tumor pathology of the thyroid gland, and thyroid cancer) who underwent treatment at LLC "Oncology Scientific Research Center" in Tbilisi, Georgia between 2020-2021.  In patients' blood the thyroid hormones content, the oxidative metabolism parameters (activity of nonenzymatic antioxidant system (TAA), malondialdehyde (MDA) content),  geometrical and rheological (deformability index (EDI), membrane proteins content) characteristics of erythrocytes were determined.

RESULTS

in the patient's blood serum with benign tumor (47 patients) MDA exceeded (p<0.005) and TAA decreased (p<0.005) in comparison to the control level; in patients with thyroid cancer (35 patients), MDA also exceeded (p<0.005), while TAA increased (p<0.005) up to the control level. In patients with benign and malignant tumors, the size of erythrocytes increased compared to the control indicators (p<0.005); in patients with thyroid cancer and benign tumors with a family history of cancer (29 patients) EDI increased (p<0.005), content of GLUT1 in erythrocyte membranes decreased (p<0.005) compared to the control level.

CONCLUSIONS

Alterations in redox metabolism play a crucial role in tumor formation; an imbalance between anti-/pro-oxidant systems may contribute to tumor formation and support its progression into a more malignant state. Thyroid cancer is characterized by a reduction in erythrocyte deformability, related to TSH levels. These alterations are less detectable in patients with benign thyroid tumors with a family history of cancer.

The protective role of nutritional antioxidants against oxidative stress in thyroid disorders

An imbalance between pro-oxidative and antioxidative cellular mechanisms is oxidative stress (OxS) which may be systemic or organ-specific. Although OxS is a consequence of normal body and organ physiology, severely impaired oxidative homeostasis results in DNA hydroxylation, protein denaturation, lipid peroxidation, and apoptosis, ultimately compromising cells' function and viability. The thyroid gland is an organ that exhibits both oxidative and antioxidative processes. In terms of OxS severity, the thyroid gland's response could be physiological (i.e. hormone production and secretion) or pathological (i.e. development of diseases, such as goitre, thyroid cancer, or thyroiditis). Protective nutritional antioxidants may benefit defensive antioxidative systems in resolving pro-oxidative dominance and redox imbalance, preventing or delaying chronic thyroid diseases. This review provides information on nutritional antioxidants and their protective roles against impaired redox homeostasis in various thyroid pathologies. We also review novel findings related to the connection between the thyroid gland and gut microbiome and analyze the effects of probiotics with antioxidant properties on thyroid diseases.

Mechanism Study on Chinese Medicine in Treatment of Nodular Goiter

Nodular goiter has become increasingly prevalent in recent years. Clinically, there has been a burgeoning interest in nodular goiter due to the risk of progression to thyroid cancer. This review aims to provide a comprehensive summary of the mechanisms underlying the therapeutic effect of Chinese medicine (CM) in nodular goiter. Articles were systematically retrieved from databases, including PubMed, Web of Science and China National Knowledge Infrastructure. New evidence showed that CM exhibited multi-pathway and multi-target characteristics in the treatment of nodular goiter, involving hypothalamus-pituitary-thyroid axis, oxidative stress, blood rheology, cell proliferation, apoptosis, and autophagy, especially inhibition of cell proliferation and promotion of cell apoptosis, involving multiple signal pathways and a variety of cytokines. This review provides a scientific basis for the therapeutic use of CM against nodular goiter. Nonetheless, future studies are warranted to identify more regulatory genes and pathways to provide new approaches for the treatment of nodular goiter.

The Influence of Oxidative Stress on Thyroid Diseases

Thyroid diseases, including neoplasms, autoimmune diseases and thyroid dysfunctions, are becoming a serious social problem with rapidly increasing prevalence. The latter is increasingly linked to oxidative stress. There are many methods for determining the biomarkers of oxidative stress, making it possible to evaluate the oxidative profile in patients with thyroid diseases compared to the healthy population. This opens up a new perspective for investigating the role of elevated parameters of oxidative stress and damage in people with thyroid diseases, especially of neoplastic nature. An imbalance between oxidants and antioxidants is observed at different stages and in different types of thyroid diseases. The organ, which is part of the endocrine system, uses free radicals (reactive oxygen species, ROS) to produce hormones. Thyroid cells release enzymes that catalyse ROS generation; therefore, a key role is played by the internal defence system and non-enzymatic antioxidants that counteract excess ROS not utilised to produce thyroid hormones, acting as a buffer to neutralise free radicals and ensure whole-body homeostasis. An excess of free radicals causes structural cell damage, undermining genomic stability. Looking at the negative effects of ROS accumulation, oxidative stress appears to be implicated in both the initiation and progression of carcinogenesis. The aim of this review is to investigate the oxidation background of thyroid diseases and to summarise the links between redox imbalance and thyroid dysfunction and disease.