Dietary Glycemic Index Differentially Modulates Cognitive and Social Behaviors in Adult WAG/Rij Rats

Abstract

Aim: Absence epilepsy is frequently accompanied by cognitive and social comorbidities, which may be influenced by environmental and metabolic factors. This study examined whether diets differing in glycemic index (GI) modulate cognitive and social behaviors in adult WAG/Rij rats, a well-established genetic model of absence epilepsy. Methods: Male WAG/Rij rats (n = 30) were randomly assigned to three groups: control diet, low glycemic index (LGI) diet, and high glycemic index (HGI) diet. Cognitive performance and exploratory behavior were assessed using the novel object recognition (NOR) test. Social interaction and social recognition memory were evaluated using the three-chamber paradigm. Results: The LGI group showed improved novel object recognition compared to controls (p < 0.05), whereas the HGI group exhibited reduced performance compared to both control (p < 0.05) and LGI groups (p < 0.001). Exploratory behavior (rearing) was higher in the LGI group than in controls (p = 0.0062), with no differences between other groups. Self-grooming and baseline social preference did not differ significantly (p > 0.05). However, social discrimination was impaired in the HGI group compared to control (p = 0.0089) and LGI groups (p = 0.0115), with no difference between control and LGI groups. Conclusions: An LGI diet enhances exploratory activity and recognition memory, whereas an HGI diet selectively impairs object recognition and social discrimination without affecting baseline sociability. These findings suggest that dietary GI differentially modulates cognitive and social behaviors in WAG/Rij rats.

Keywords

• Absence epilepsy
• cognition
• glycemic index
• social behaviors
• WAG/Rij rats

Ethical Statement

Bu çalışma, Kocaeli Üniversitesi Hayvan Deneyleri Yerel Etik Kurulu tarafından onaylanmıştır (Karar No: KOÜ HADYEK 6/8-2025, Karar Tarihi: 25.06.2025). Tüm deneysel prosedürler ulusal ve uluslararası etik kurallara uygun olarak yürütülmüştür.

Diyetin Glisemik İndeksi, Erişkin WAG/Rij Sıçanlarda Bilişsel ve Sosyal Davranışları Farklı Şekilde Modüle Eder

Abstract

Amaç: Absans epilepsi, çevresel ve metabolik faktörlerden etkilenebilen bilişsel ve sosyal eşlik eden durumlarla sıklıkla birlikte görülür. Bu çalışma, glisemik indeks (Gİ) açısından farklılık gösteren diyetlerin, absans epilepsinin iyi tanımlanmış genetik bir modeli olan erişkin WAG/Rij sıçanlarda bilişsel ve sosyal davranışları modüle edip etmediğini incelemeyi amaçlamıştır. Yöntem: Erkek WAG/Rij sıçanlar (n = 30) rastgele üç gruba ayrılmıştır: kontrol diyeti, düşük glisemik indeksli (DGİ) diyet ve yüksek glisemik indeksli (YGİ) diyet. Bilişsel performans ve keşif davranışı, yeni nesne tanıma (YNT) testi ile değerlendirilmiştir. Sosyal etkileşim ve sosyal tanıma belleği ise üç bölmeli test paradigması kullanılarak incelenmiştir. Bulgular: DGİ diyet grubu, kontrol grubuna kıyasla daha yüksek yeni nesne tanıma performansı göstermiştir (p < 0.05). Buna karşılık, YGİ diyet grubu hem kontrol (p < 0.05) hem de DGİ gruplarına göre daha düşük performans sergilemiştir (p < 0.001). Keşif davranışı (rearing) DGİ grubunda kontrole göre daha yüksek bulunmuştur (p = 0.0062); diğer gruplar arasında fark saptanmamıştır. Kendini temizleme davranışı ve temel sosyal tercih açısından gruplar arasında anlamlı fark bulunmamıştır (p > 0.05). Ancak sosyal ayırt etme performansı, YGİ grubunda kontrol (p = 0.0089) ve DGİ gruplarına (p = 0.0115) göre anlamlı düzeyde bozulmuştur. Kontrol ve DGİ grupları arasında fark gözlenmemiştir. Sonuç: DGİ diyeti keşif aktivitesi ve tanıma belleğini artırırken, YGİ diyeti temel sosyalliği etkilemeden nesne tanıma ve sosyal ayırt etme performansını seçici olarak bozmuştur. Bu bulgular, diyetin glisemik indeksinin WAG/Rij sıçanlarda bilişsel ve sosyal davranışları farklı şekillerde modüle ettiğini göstermektedir.

Keywords

• Absans epilepsi
• bilişsel işlevler
• glisemik indeks
• sosyal davranışlar
• WAG/Rij sıçanları

Ethical Statement

This study was approved by the Kocaeli University Animal Experiments Local Ethics Committee (Approval No: KOÜ HADYEK 6/8-2025, Decision Date: 25.06.2025). All experimental procedures were conducted in accordance with national and international ethical guidelines.

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