In Vivo Hepatoprotective and Nephroprotective Activity of Acylated Iridoid Glycosides from Scrophularia hepericifolia

Abstract

Phytochemical investigation of the chloroform fraction obtained from Scrophularia hypericifolia aerial parts led to the isolation of nine acylated iridoid glycosides. The new compounds were identified as 6-O-α-L(2″-acetyl, 3″,4″-di-O-trans-cinnamoyl) rhamnopyranosyl-6′-acetyl catalpol (6′-acetyl hypericifolin A) (1), 6-O-α-L(2″, 4″-diacetyl, 3″-O-trans-cinnamoyl) rhamnopyranosyl-6′-acetyl catalpol (6′-acetyl hypericifolin B) (2), 6-O-α-L(2″-acetyl, 3″,4″-di-O-trans-cinnamoyl) rhamnopyranosyl catalpol (hypericifolin A) (3) and 6-O-α-L(2″, 4″-diacetyl, 3″-O-trans-cinnamoyl) rhamnopyranosyl catalpol (hypericifolin B) (4). Previously reported compounds were identified as laterioside (5), 8-O-acetylharpagide (6), 6-O-α-L(4′-O-trans-cinnamoyl) rhamnopyranosyl catalpol (7), lagotisoside D (8) and harpagoside (9). Identification achieved via analyses of physical and spectral data including 1D, 2D NMR and High Resolution Electrospray Ionization Mass spectroscopy (HRESIMS). Compounds 2–4 and 6 were subjected to biological evaluation against paracetamol-induced toxicity. The biochemical parameters aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (GGT) as well as total bilirubin were used to access the liver condition. Measurement of serum levels of urea, creatinine, sodium and potassium cations were indicators for kidney condition. Liver and kidney samples were subjected to histopathological study. The best protection was found in the group treated with 3 followed by 4 and 6, while 2 was almost inactive.