Unveiling Oxidative Stress Dynamics: A Comparative Study of Biochemical and Anti-Oxidative Parameters in Thyroid Dysfunction

Abstract

Background: The prevalence of thyroid dysfunction is significant, and its association with oxidative stress and biochemical changes is well recognized. Thyroid hormones are crucial in maintaining oxidative balance and regulating the body's metabolic processes to protect against cellular damage.Objectives: The study aimed to compare biochemical and oxidative stress parameters in rat models of hypothyroidism and hyperthyroidism.Materials and Methods: This research, conducted from September 14 to October 21, 2023, involved 21 male Wistar divided into hypothyroid (n=7), hyperthyroid (n=7), and control (n=7), respectively. Hypothyroidism and hyperthyroidism were induced using propylthiouracil (PTU) and levothyroxine (LTX), respectively. The study assessed serum biochemical parameters, including uric acid (UA), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and total cholesterol (TC), as well as oxidative stress parameters, such as total antioxidant capacity (TAC) after 5-weeks.Results: The study found that the hypothyroid group exhibited decreased TAC (40±4) compared to the hyperthyroid (45±6) and control (50±5; p=0.012) groups. UA levels were higher in hypothyroid rats (4.2±1.0 mg/dL). Both hypothyroid (200±18 U/L) and hyperthyroid (210±20 U/L) rats showed increased LDH levels compared to the control group (180±15 U/L). Additionally, LDL cholesterol was elevated in hypothyroid (55±8 mg/dL) and reduced in hyperthyroid rats (30±5 mg/dL), while HDL decreased in both groups.Conclusion: Hypothyroidism is associated with significantly lower TAC and higher levels of UA and LDH, indicating oxidative stress and cellular damage. Conversely, hyperthyroidism leads to altered lipid metabolism, as evidenced by decreased LDL and HDL cholesterol levels. Keywords: Anti-oxidants, Lipid metabolism, Rats, Thyroid disorders.