Immunolocalization of BECLIN 1 (BECN1) in Rat Small Intestine During Nutrient Starvation

Abstract

The aim of this study was to investigate how different durations of fasting affect autophagy levels by analyzing Beclin 1 (BECN1) expression in rat small intestinal tissues using immunohistochemistry. Thirty adult male Wistar Albino rats were allocated into five groups (n=6 each). After the last feeding, the fasting groups were classified according to fasting durations of 12, 24, 36, and 48 hours, and water was provided without restriction. At the end of the experimental period, small intestine samples were collected from the rats in each group. Tissue samples fixed in Bouin’s solution were embedded in paraffin. To detect BECN1 immunolocalization, the tissues were subjected to immunohistochemical analysis using the streptavidin–biotin technique. BECN1 immunoreactivity was analyzed semi-quantitatively. At the light-microscopy level, no structural changes were detected in any region of the small intestine (duodenum, jejunum, ileum) when the fasting groups were compared with the control group. BECN1 expression was found to be localized in all groups across all small intestinal sections in villus epithelial cells, glandular epithelial cells, and the tunica muscularis layer. In all groups, BECN1 immunolocalization was observed in all regions of the small intestine, specifically in villus epithelial cells, glandular epithelial cells, and the tunica muscularis layer, with a moderate (++) staining intensity. No statistically significant difference in staining intensity was recorded between the groups (p>0.05). These results indicate that short- to moderate-term fasting (12–48 hours) does not produce a measurable change in basal BECN1-associated autophagy in the rat small intestine.

Keywords

• Autophagy
• BECN1
• nutrient starvation
• rat
• small intestine

BESİN AÇLIĞI DURUMUNDA SIÇAN İNCE BARSAK DOKUSUNDA BECN1 (BECLİN 1) İMMÜNOLOKALİZASYONU

Abstract

Bu çalışmanın amacı, immünohistokimyasal düzeyde sıçan ince bağırsak dokularında Beclin 1 (BECN1) ekspresyonunu analiz ederek farklı açlık sürelerinin otofaji düzeylerini nasıl etkilediğini araştırmaktı. Otuz yetişkin erkek Wistar Albino sıçan beş gruba ayrıldı (her grupta 6 sıçan). Son beslenmeden sonra, deney hayvanları 12, 24, 36 ve 48 saatlik açlık sürelerine göre sınıflandırıldı ve su kısıtlama olmaksızın verildi. Deney süresinin sonunda, her gruptaki sıçanlardan ince bağırsak örnekleri alındı. Bouin solüsyonunda tespit edilen doku örnekleri parafine gömüldü. BECN1 immünolokalizasyonunu tespit etmek için dokular, streptavidin-biotin tekniği kullanılarak immünohistokimyasal analize tabi tutuldu. BECN1 immünoreaktivitesi yarı kantitatif olarak analiz edildi. Işık mikroskobu düzeyinde, açlık grupları kontrol grubu ile karşılaştırıldığında ince bağırsağın hiçbir bölgesinde (duodenum, jejunum, ileum) yapısal değişiklik tespit edilmedi. BECN1 ekspresyonunun tüm gruplarda tüm ince bağırsak kesitlerinde villus epitel hücrelerinde, glandüler epitel hücrelerinde ve tunika muskularis tabakasında lokalize olduğu görüldü. Tüm gruplarda, BECN1 immünolokalizasyonu ince bağırsağın tüm bölgelerinde, özellikle villus epitel hücrelerinde, glandüler epitel hücrelerinde ve tunika muskularis tabakasında orta derecede (++) boyama yoğunluğu ile gözlemlenmiştir. Gruplar arasında boyama yoğunluğunda istatistiksel olarak anlamlı bir fark kaydedilmedi (p>0.05). Bu sonuçlar, kısa ila orta süreli açlığın (12-48 saat) sıçanların ince bağırsaklarında BECN1 ile ilişkili otofaji üzerinde ölçülebilir bir değişiklik yaratmadığını göstermektedir.

Keywords

• Otofaji
• BECN1
• Besin açlığı
• Sıçan
• İnce bağırsak

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