Effects of boric acid on reproductive hormones and utero-ovarian tissues in female rats: A dose-response study

Abstract

Boric acid is a widely used form of boron, and its potential as a therapeutic agent is being increasingly investigated. This study aimed to evaluate the dose-dependent effects of oral boric acid administration on reproductive hormone levels and the histopathological architecture of ovarian and uterine tissues in female rats. Twenty-four young adult female rats were randomly divided into four groups: control, low-dose boric acid (10 mg/kg), medium-dose boric acid (100 mg/kg), and high-dose boric acid (1000 mg/kg). Boric acid or saline was administered orally once daily for 21 days. Serum estradiol and progesterone levels were measured and ovarian and uterine tissues were examined histopathologically. Low and medium doses of boric acid did not significantly alter estradiol or progesterone levels compared to controls (p>0.05). However, high-dose boric acid administration significantly decreased estradiol levels while increasing progesterone levels (p<0.05). Histological evaluation revealed dose-dependent pathological changes, including edema, vascular congestion, follicular degeneration in the ovaries, and hyperplasia of endometrial glands in the uterus, particularly prominent at high doses. Boric acid exposure at high doses could disrupt the hormonal balance and induce significant structural damage in reproductive tissues, suggesting a potential risk to female reproductive health. These findings emphasize the necessity for cautious evaluation of boric acid exposure levels, particularly given its widespread industrial and medical applications.

Keywords

• Boric acid
• Estradiol
• Progesterone
• Uterus
• Ovary

Borik asidin dişi sıçanlarda üreme hormonları ve uterus-ovaryum dokuları üzerindeki etkileri: Doz-yanıt çalışması

Abstract

Borik asit, yaygın olarak kullanılan bir bor formu olup terapötik ajan olarak potansiyeli giderek daha fazla araştırılmaktadır. Bu çalışma, oral borik asit uygulamasının doz bağımlı etkilerini dişi sıçanlarda üreme hormon düzeyleri ile over ve uterus dokularının histopatolojik yapısı üzerinde değerlendirmeyi amaçlamıştır. Yirmi dört genç dişi sıçan rastgele olarak dört gruba ayrılmıştır: Kontrol, düşük doz borik asit (10 mg/kg), orta doz borik asit (100 mg/kg) ve yüksek doz borik asit (1000 mg/kg). Borik asit veya salin solüsyonu, 21 gün boyunca günde bir kez oral yolla uygulandı. Serum östradiol ve progesteron düzeyleri ölçüldü, over ve uterus dokuları histopatolojik olarak incelendi. Düşük ve orta doz borik asit uygulamaları, kontrol grubuna kıyasla östradiol ve progesteron düzeylerinde anlamlı değişiklik oluşturmadı (p>0,05). Ancak yüksek doz borik asit uygulaması, östradiol düzeylerini anlamlı olarak azaltırken progesteron düzeylerini artırdı (p<0,05). Histopatolojik değerlendirmede, doza bağlı olarak over dokusunda ödem, vasküler konjesyon ve foliküler dejenerasyon gözlendi. Uterus dokusunda ise özellikle yüksek dozlarda belirgin endometriyal bez hiperplazisi ve şiddetli vasküler hiperemi tespit edildi. Yüksek doz borik asit maruziyeti, hormonal dengeyi değiştirerek ve üreme dokularında belirgin yapısal hasara yol açabileceğinden, kadın üreme sağlığı açısından potansiyel risk oluşturabileceği sonucuna varılmıştır. Bu bulgular, borik asidin yaygın endüstriyel ve tıbbi uygulamaları göz önünde bulundurularak, maruziyet düzeylerinin dikkatle değerlendirilmesi gerekliliğini vurgulamaktadır.

Keywords

• Borik asit
• Estradiol
• Progesteron
• Rahim
• Yumurtalık

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