Abstract

Nar kabuğu, yüksek antioksidan aktiviteye sahip flavonoitler, elajitanenler, fenolikler ve proantosiyanidin bileşikleri gibi biyoaktif bileşenler içermesi nedeniyle en faydalı parçalardan biridir. Nar kabuğundaki yüksek punikalagin içeriği, antienflamatuvar, antioksidan ve antiapoptotik etkiler üretmesini sağlar. Bu çalışmada deneysel lipopolisakkarit (LPS) kaynaklı üveit modelinde nar kabuğu ekstresinin (NKE) koruyucu etkilerini değerlendirmeyi amaçladık. 60 sıçan rastgele 12 gruba ayrıldı (n = 5). Sağlıklı grup intraperitoneal normal salin; üveit grubu 200 μg/kg LPS; deksametazon (DEX) grubu 200 μg/kg LPS ve 1 mg/kg DEX; NKE100, NKE300 ve NKE500 grupları ise 200 μg/kg LPS ile birlikte sırasıyla 100, 300 ve 500 mg/kg NKE aldı. Göz dokuları 3. ve 24. saatte toplandı ve moleküler, biyokimyasal ve histopatolojik olarak incelendi. NKE uygulamasını takiben üveitik sıçanlarda tümör nekroz faktörü-α, vasküler endotelyal büyüme faktörü ve kaspaz-3 seviyeleri doza bağlı olarak belirgin şekilde azaldı. NKE uygulaması, doza bağlı olarak artan etkileri ile Glutatyon, Süperoksit dismutaz ve Malondialdehit gibi oksidatif strese bağlı faktörlerdeki üveitik bozuklukları önemli ölçüde iyileştirdi. NKE ayrıca üveit ile ilişkili göz dokularındaki histopatolojik değişiklikleri de ortadan kaldırdı. NKE, antienflamatuvar, antioksidan, antiapoptotik ve antianjiyojenik etkileri ile üveit için alternatif koruyucu tedavi yöntemlerine katkıda bulunarak umut verici bir ajan olabilir.

Keywords

• Anti-inflammatory
• Antioxidant
• LPS-induced uveitis
• Pomegranate peel
• Punicalagin
• TNF-α

Project Number

NKUBAP.02.GA.20.240

INVESTIGATION OF THE PROTECTIVE EFFECTS OF POMEGRANATE (Punica granatum L.) PEEL EXTRACT ON LIPOPOLYSACCHARIDE-INDUCED UVEITIS IN RATS

Abstract

Pomegranate peel contains bioactive ingredients such as flavonoids, ellagitannins, phenolics and proanthocyanidin compounds with high antioxidant activity. Pomegranate peel has antiapoptotic, antioxidant and anti-inflammatory effects due to its high punicalagin content. We aimed to determine the effect of pomegranate peel extract (PPE) on lipopolysaccharide (LPS)-induced uveitis. Sixty rats were seperated randomly into twelve groups (n = 5). The healthy group received intraperitoneal normal saline, the uveitis group received 200 μg/kg LPS, the dexamethasone (DEX) group received 200 μg/kg LPS plus 1 mg/kg DEX, the PPE100, PPE300 and PPE500 groups received 200 μg/kg LPS plus 100, 300 and 500 mg/kg PPE, respectively. The eye tissues were collected at 3rd and 24th hour. and investigated molecularly (Relative quantification of gene expression), biochemically (Superoxide dismutase activity, Glutathione and Malondialdehyde levels) and histopathologically (staining with Harris Hematoxylin and Eosin Y). Tumor Necrosis Factor-α, vascular endothelial growth factor, and Caspase-3 levels markedly decreased in a dose-dependent manner in the uveitic rats following PPE administration. PPE administration significantly ameliorated uveitic disorders in oxidative stress factors including Glutathione, Superoxide dismutase and Malondialdehyde, with its effects raising in a dose-dependent manner. PPE eliminated histopathological changes in eye tissues due to uveitis. PPE can be a promising agent by contributing to alternative preventive treatment methods for uveitis with its anti-inflammatory, antioxidative, antiapoptotic and antiangiogenic effects.

Keywords

• Anti-inflammatory
• Antioxidant
• LPS-induced uveitis
• Pomegranate peel
• Punicalagin
• TNF-α

Supporting Institution

the Scientific Research Council of Tekirdağ Namık Kemal University

Project Number

NKUBAP.02.GA.20.240

Thanks

Part of this study was presented orally at the 5th International Hippocrates Congress on Medical and Health Sciences on 18-19 December 2020.

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