Effects of Letrozole Administration on Metabolic, Inflammatory, and Oxidative Responses in Rat Serum and Brain Tissue

Mustafa Ermiş; Erol Karakaş; Hanifi Erol; Recai Aci; Furkan Ümit; Gülay Çiftci

doi:10.35229/jaes.1801041

TR EN

Letrozol Uygulamasının Rat Serum ve Beyin Dokusunda Metabolik, İnflamatuar ve Oksidatif Yanıtlar Üzerine Etkileri

Öz

Letrozol, östrojen sentezini azaltan ve meme kanseri tedavisinde kullanılan bir ilaçtır. Uzun süreli kullanımı sistemik ve nörolojik etkiler oluşturabilir. Bu çalışmada, Letrozol uygulanan dişi ratlarda biyokimyasal, inflamatuar ve nörolojik parametreler incelendi. Çalışma, 6’şar ratlı kontrol ve Letrozol (1 mg/kg, 21 gün) gruplarından oluştu. 21. gün sonunda ratlardan kan ve beyin dokusu örnekleri alındı. Proinflamatuar sitokinler ve Aβ₁₋₄₀ düzeyleri ELISA ile toplam antioksidan (TAS) ve toplam oksidan (TOS) düzeyleri Relassay kitleriyle, biyokimyasal parametreler ve mineraller ise otoanalizörle ölçüldü. Analizlerde, Letrozol grubunda total protein, albümin, glukoz ve serum sodyum düzeylerinde anlamlı artış; ürede ise azalma saptandı (P<0.05). Lipid profilindeki değişiklikler anlamlı değildi (P>0.05). Beyin dokusunda trigliserit ve total kolesterol düzeyleri anlamlı arttı (P<0.05). Serumda IL-1α, IL-1β, TNF-α, NF-κB ve Aβ₁₋₄₀ düzeyleri artarken (P<0.01), TAS azaldı (P<0.05). Beyin dokusunda trigliserit ve total kolesterol düzeylerinde anlamlı artış gözlendi (P<0.05). Serumda IL-1α, IL-1β, TNF-α, NF-κB ve Aβ₁₋₄₀ düzeyleri artarken (P<0.01), TAS azaldı (P<0.05). Beyin dokusunda ise yalnızca IL-1β ve NF-κB düzeylerinde anlamlı artış saptandı (P<0.05). Sonuç olarak, Letrozol kullanımının sistemik inflamasyon ve oksidatif stresi artırdığı; ancak beyin üzerindeki etkilerinin daha sınırlı olduğu görüldü. Artan amiloid beta düzeyleri ise nöroinflamasyon ve potansiyel nörodejeneratif risklerin göstergesi olarak değerlendirildi.

Anahtar Kelimeler

Aβ₁₋₄₀ , beyin , inflamasyon , letrozole , oksidatif stres , rat

Effects of Letrozole Administration on Metabolic, Inflammatory, and Oxidative Responses in Rat Serum and Brain Tissue

Abstract

Letrozole is a drug that reduces estrogen synthesis and is used in the treatment of breast cancer. Its long-term use may cause systemic and neurological effects. In this study, biochemical, inflammatory, and neurological parameters were examined in female rats administered Letrozole. The study consisted of control and Letrozole groups (1 mg/kg for 21 days), each with 6 rats. On day 21, blood and brain tissue samples were collected from the rats. Proinflammatory cytokines and Aβ₁₋₄₀ levels were measured by ELISA, total antioxidant status (TAS) and total oxidant status (TOS) levels by Relassay kits, and biochemical parameters and minerals by an autoanalyzer. Analyses showed significant increases in total protein, albumin, glucose, and serum sodium levels, and a decrease in urea in the Letrozole group (P<0.05). Changes in the lipid profile were not significant (P>0.05). Triglyceride and total cholesterol levels in brain tissue increased significantly (P<0.05). Serum levels of IL-1α, IL-1β, TNF-α, NF-κB, and Aβ₁₋₄₀ increased (P<0.01), while TAS decreased (P<0.05). In the brain, only IL-1β and NF-κB levels were elevated (P<0.05). In conclusion, Letrozole increases systemic inflammation and oxidative stress, with more limited effects on the brain. The elevated amyloid beta levels indicate neuroinflammation and potential neurodegenerative risks.

Keywords

brain, , inflammation , letrozole , Aβ₁₋₄₀ , oxidative stress , rat

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Details

Primary Language

English

Subjects

Veterinary Biochemistry

Journal Section

Research Article

Authors

Mustafa Ermiş
0000-0003-2267-1238
Türkiye

Erol Karakaş
0000-0001-6050-6765
Türkiye

Hanifi Erol
0000-0001-8140-3108
Türkiye

Recai Aci
0000-0002-1517-3356
Türkiye

Furkan Ümit
0009-0004-3556-5519
Türkiye

Gülay Çiftci ^*
0000-0001-5384-2381
Türkiye

Publication Date

January 7, 2026

Submission Date

October 13, 2025

Acceptance Date

December 12, 2025

Published in Issue

Year 2026 Number: 2026

DOI

https://doi.org/10.35229/jaes.1801041

IZ

https://izlik.org/JA26RL45FS

APA

Ermiş, M., Karakaş, E., Erol, H., Aci, R., Ümit, F., & Çiftci, G. (2026). Effects of Letrozole Administration on Metabolic, Inflammatory, and Oxidative Responses in Rat Serum and Brain Tissue. Journal of Anatolian Environmental and Animal Sciences, 2026, 1-9. https://doi.org/10.35229/jaes.1801041

EBSCOHost Scilit CABI

JAES/AAS-Journal of Anatolian Environmental and Animal Sciences/Anatolian Academic Sciences&Anadolu Çevre ve Hayvancılık Dergisi/Anadolu Akademik Bilimler-AÇEH/AAS

Letrozol Uygulamasının Rat Serum ve Beyin Dokusunda Metabolik, İnflamatuar ve Oksidatif Yanıtlar Üzerine Etkileri

Öz

Anahtar Kelimeler

Effects of Letrozole Administration on Metabolic, Inflammatory, and Oxidative Responses in Rat Serum and Brain Tissue

Abstract

Keywords

References

Details

Primary Language

Subjects

Journal Section

Authors

Publication Date

Submission Date

Acceptance Date

Published in Issue

DOI

IZ

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