Thioredoxin reductase gene expression and activity among human T‐cell lymphotropic virus type 1–infected patients

• Published in: Journal of medical virology Vol. 91; no. 5; pp. 865 - 871
• Main Authors: Yaghoubi, Neda, Youssefi, Masoud, Hashemy, Seyed Isaac, Rafat Panah, Houshang, Mashkani, Barat Ali, Zahedi Avval, Farnaz
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.05.2019
• Subjects: Adult; Apoptosis; Blood; Central nervous system diseases; Complications; Enzymatic activity; Enzyme activity; Enzymes; Female; Gene Expression; Gene Expression Profiling; HAM‐TSP; Hereditary spastic paraplegia; HTLV-I Infections - pathology; HTLV‐1; Humans; Infections; Leukocytes (mononuclear); Male; Middle Aged; NADP; Oxidative Stress; Patients; Peripheral blood mononuclear cells; Polymerase chain reaction; Reactive oxygen species; real time PCR; Real-Time Polymerase Chain Reaction; Reductase; Sampling methods; Spinal cord; Thioredoxin; thioredoxin reductase; Thioredoxin-Disulfide Reductase - blood; Tropical spastic paraparesis; Virology; Viruses; real time PCR; HTLV-1; HAM-TSP; thioredoxin reductase
• ISSN: 0146-6615; 1096-9071
• DOI: 10.1002/jmv.25371

Background The thioredoxin (Trx) system is a reducing complex, consisting of Trx, Trx reductase (TrxR), and NADPH, that scavenges reactive oxygen species. The system is a natural protective mechanism to prevent apoptosis and progression of oxidative stress‐related diseases. The present study was conducted to explore possible changes in TrxR activity and gene expression as a response to the oxidative stress during HTLV‐1 infection. Materials and Methods Blood samples were collected from 40 HTLV‐1‐infected patients and 40 age‐ and sex‐matched healthy controls. The patient group consisted of chronic asymptomatic carriers and HTLV‐1‐associated myelopathy/tropical spastic paraparesis (HAM‐TSP) patients. A commercial kit was used to measure the TrxR enzyme activity, and real‐time polymerase chain reaction was performed to evaluate TrxR gene expression in extracted peripheral blood mononuclear cells (PBMCs). Results A decreasing pattern of TrxR enzyme activity was observed among control, carrier, and HAM‐TSP groups (mean ± SD; controls, 0.1734 ± 0.056; carriers, 0.134 ± 0.065; and HAM‐TSP, 0.0928 ± 0.047 µmol/min/mL). Cellular TrxR gene expression showed the same decreasing trend. The fold differences of gene expression in carriers and HAM‐TSP groups compared with healthy controls were 0.8 and 0.7 vs 1, respectively. Conclusion We found a reduction in TrxR expression as well as serum enzyme activity in HTLV‐1‐infected individuals, particularly in HAM‐TSP patients. The reduced TrxR activity during HTLV‐1 infection may hamper the natural protective mechanisms, thereby contributes to virus‐induced complications.