Centaurium erythraea methanol extract protects red blood cells from oxidative damage in streptozotocin-induced diabetic rats.
BACKGROUND
Centaurium erythraea Rafn (CE) is a traditional medicinal herb in Serbia with antidiabetic, digestive, antipyretic and antiflatulent effects AIM OF THE STUDY: To investigate the potential protective effects of the methanol extract of the aerial parts of CE against glyco-oxidative stress in red blood cells (RBCs) in rats with experimentally induced diabetes.


METHODS
Diabetes was induced in Wistar rats by intraperitoneal (i.p.) injection of multiple low-dose streptozotocin (STZ) (40mg/kg, for five consecutive days), with the 1st day after the last STZ injection taken as the day of diabetes onset. The methanol extract of CE (100mg/kg) was administered orally and daily, two weeks before the first STZ injection, during the 5-day treatment with STZ, and for four weeks after the STZ injections (pre-treated group) or for four weeks after diabetes onset (post-treated group). The effect of CE extract administration on the redox status of RBCs was evaluated by assessing lipid peroxidation, the ratio of reduced/oxidized glutathione (GSH/GSSG), the level of S-glutathionylated proteins (GSSP) and the enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) in RBCs four weeks after diabetes onset. The major biochemical parameters of diabetes, protein glycation/glycosylation of erythrocytes and parameters which correlate with their aggregation and deformability were also evaluated.


RESULTS
Daily application of CE extract to STZ-induced diabetic rats provided important antidiabetic effects, observed in both pre-treated and post-treated groups of diabetic rats as elevated serum insulin concentration, reduction of blood glucose and glycated hemoglobin concentrations and an improved lipid profile. Antioxidant effects of CE extract were detected in RBCs of diabetic rats and observed as decreased lipid peroxidation and ameliorated oxidative damage as a result of increased SOD, CAT and GR activities, an improved GSH/GSSG ratio and reduced GSSP levels. Moreover, the CE extract protected RBC proteins from hyperglycemia-induced damage by reducing non-enzymatic glycation and enzymatic glycosylation processes. CE extract was more effective when applied before diabetes induction (pre-treated group).


CONCLUSIONS
The results of this study show that the Centaurium erythraea methanol extract protects RBCs in diabetic animals from oxidative damage. They provide additional support for the application of this traditionally used plant in diabetes management.
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: milos.djordjevic@ibiss.bg.ac.rs.
Miloš
M
Đorđević
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: mista@ibiss.bg.ac.rs.
Mirjana
M
Mihailović
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: jelena.arambasic@ibiss.bg.ac.rs.
Jelena
J
Arambašić Jovanović
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: nevenag@ibiss.bg.ac.rs.
Nevena
N
Grdović
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: auskokovic@ibiss.bg.ac.rs.
Aleksandra
A
Uskoković
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: anja.tolic@ibiss.bg.ac.rs.
Anja
A
Tolić
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: marija.sinadinovic@ibiss.bg.ac.rs.
Marija
M
Sinadinović
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: jovana.rajic@ibiss.bg.ac.rs.
Jovana
J
Rajić
Department of Plant Physiology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: dmisic@ibiss.bg.ac.rs.
Danijela
D
Mišić
Department of Plant Physiology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: branislav.siler@ibiss.bg.ac.rs.
Branislav
B
Šiler
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: goranpoz@ibiss.bg.ac.rs.
Goran
G
Poznanović
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: melita@ibiss.bg.ac.rs.
Melita
M
Vidaković
Department of Molecular Biology, Institute for Biological Research, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia. Electronic address: sdinic@ibiss.bg.ac.rs.
Svetlana
S
Dinić
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D029966:Centaurium / Q000737:chemistry*; D003921:Diabetes Mellitus, Experimental / Q000097:blood* / Q000188:drug therapy*; D004912:Erythrocytes / Q000187:drug effects*; D005419:Flavonoids / Q000032:analysis; D016166:Free Radical Scavengers / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism; D007004:Hypoglycemic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D015227:Lipid Peroxidation / Q000187:drug effects; D000432:Methanol; D018384:Oxidative Stress / Q000187:drug effects*; D010636:Phenols / Q000032:analysis; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar
D000975:Antioxidants; D001786:Blood Glucose; D005419:Flavonoids; D016166:Free Radical Scavengers; D007004:Hypoglycemic Agents; D010636:Phenols; D010936:Plant Extracts; D005978:Glutathione; D000432:Methanol
Antioxidant activity; Centaurium erythraea; Diabetes mellitus; Hyperglycemia; Oxidative stress; Red blood cells