Impact of Experimental Hyperlipidemia on Histology of Major Salivary Glands

Abstract

Objectives: To examine the histologic structure of major salivary glands in high-fat diet induced hyperlipidemic rats. Materials and Methods: Sixteen Wistar Albino rats were grouped as control group (CG) and hyperlipidemic group (HG). CG was fed a standard chow and HG was fed a high-fat diet. At the end of three months, blood samples were obtained for lipid analyses. For histological analysis, major salivary glands were evaluted under light microscopy. Results: In HG; the number of intracellular lipid droplets (ILD) in the major salivary glands significantly increased while the diameter of ILD significantly increased in the parotid and sublingual glands (p< 0.01). The cell types mainly affected were serous cells in the parotid and submandibular, serous demilunar cells and, to a lesser extent, mucous cells in the sublingual gland. Serum levels of all lipids were significantly correlated with the lipid numbers in the parotid and the sublingual glands. In the submandibular gland, only serum LDL and cholesterol levels were found to be significantly correlated with the lipid numbers (p<0.05). Conclusion: High-fat diet caused intracellular lipid accumulation in the parotid and sublingual glands without any structural alteration. Submandibular gland exerted a partial resistance to intracellular lipid accumulation. Turkish Başlık: Deneysel Hiperlipideminin Büyük Tükürük Bezlerinin Histolojisi Üzerine Etkisi Anahtar Kelimeler: Deneysel hiperlipidemi; büyük tükürük bezleri; lipid birikimi ve Oil red O Amaç: Yağ içeriği zengin diyet ile beslenerek hiperlipidemi oluşturulan sıçanlarda, büyük tükürük bezlerinin histolojik yapısını incelemektir. Gereç ve Yöntemler: On altı adet Wistar Albino sıçanı kontrol grubu (KG) ve hiperlipidemik grup (HG) olmak üzere ikiye ayrıldı. CG standart yem, HG ise yağ içeriği zengin diyet ile beslendi. Üç ay sonunda, lipit analizi için kan örnekleri alındı. Histolojik değerlendirme için, büyük tükürük bezleri ışık mikroskobu ile incelendi. Bulgular: Hiperlipidemik gruba ait büyük tükürük bezlerinde hücre içi lipit damlacıklarının sayısında anlamlı bir artış görülürken, sublingual ve parotis bezinin hücre içi lipit damlacıklarının çapında anlamlı derecede artış tespit edildi (p<0.01). Parotis ve submandibular bezlerde esas olarak seröz hücreler, sublingual bezde ise seröz yarımlar ve daha az derecede müköz hücreler hiperlipidemiden etkilendi. Tüm serum lipit düzeyleri ile sublingual ve parotis bezde biriken lipit damlacıkları sayısı arasında istatistiksel olarak anlamlı korelasyon saptandı. Submandibular bezde ise, sadece LDL ve kolesterol düzeyleri ile lipit damlacıkları sayısı arasında anlamlı bir korelasyon tespit edildi (p<0.05). Sonuç: Yüksek yağ içeren diyet, parotis ve sublingual bezlerde yapısal bir değişikliğe neden olmaksızın, hücre içi lipit birikimine neden olmaktadır. Submandibular bez ise intraselüler lipit birikimine karşı kısmi bir direnç göstermektedir.

Keywords

• Experimental hyperlipidemia; major salivary glands; lipid accumulation and Oil red O

Deneysel Hiperlipideminin Büyük Tükürük Bezlerinin Histolojisi Üzerine Etkisi

Öz

Amaç: Yağ içeriği zengin diyet ile beslenerek hiperlipidemi oluşturulan sıçanlarda, büyük tükürük bezlerinin histolojik yapısını incelemektir. Gereç ve Yöntemler: On altı adet Wistar Albino sıçanı kontrol grubu (KG) ve hiperlipidemik grup (HG) olmak üzere ikiye ayrıldı. CG standart yem, HG ise yağ içeriği zengin diyet ile beslendi. Üç ay sonunda, lipit analizi için kan örnekleri alındı. Histolojik değerlendirme için, büyük tükürük bezleri ışık mikroskobu ile incelendi. Bulgular: Hiperlipidemik gruba ait büyük tükürük bezlerinde hücre içi lipit damlacıklarının sayısında anlamlı bir artış görülürken, sublingual ve parotis bezinin hücre içi lipit damlacıklarının çapında anlamlı derecede artış tespit edildi (p < 0.01). Parotis ve submandibular bezlerde esas olarak seröz hücreler, sublingual bezde ise seröz yarımlar ve daha az derecede müköz hücreler hiperlipidemiden etkilendi. Tüm serum lipit düzeyleri ile sublingual ve parotis bezde biriken lipit damlacıkları sayısı arasında istatistiksel olarak anlamlı korelasyon saptandı. Submandibular bezde ise, sadece LDL ve kolesterol düzeyleri ile lipit damlacıkları sayısı arasında anlamlı bir korelasyon tespit edildi (p < 0.05). Sonuç: Yüksek yağ içeren diyet, parotis ve sublingual bezlerde yapısal bir değişikliğe neden olmaksızın, hücre içi lipit birikimine neden olmaktadır. Submandibular bez ise intraselüler lipit birikimine karşı kısmi bir direnç göstermektedir.

Anahtar Kelimeler

• Deneysel hiperlipidemi, büyük tükürük bezleri, lipid birikimi ve Oil red O

Kaynakça

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