A Lanosteryl triterpene from Protorhus longifolia augments insulin signaling in type 1 diabetic rats
Date
2018-10-01
Journal Title
Journal ISSN
Volume Title
Publisher
BMC (part of Springer Nature)
Abstract
Background: A substantial literature supports antidiabetic properties of the lanosteryl triterpene (methyl-3β-
hydroxylanosta-9,24-dien-21-oate, RA-3) isolated from Protorhus longifolia stem bark. However, the molecular
mechanism(s) associated with the antihyperglycemic properties of the triterpene remained to be explored. The
current study aimed at investigating the molecular mechanism(s) through which RA-3 improves insulin signaling
in streptozotocin-induced type 1 diabetic rats.
Methods: The type 1 diabetic rats were treated daily with a single oral dose of RA-3 (100 mg/kg) for 28 days.
The rats were then sacrificed, and blood, skeletal muscle and pancreases were collected for biochemical, protein
expression and histological analysis, respectively.
Results: Persistently high blood glucose levels in the diabetic control rats significantly increased expression of
IRS-1Ser307 while the expression of p-Akt Ser473, p-GSK-3β Ser9, GLUT 4 and GLUT 2 were decreased. However, enhanced
muscle insulin sensitivity, which was indicated by a decrease in the expression of IRS-1ser307 with a concomitant increase
in the p-AktSer473, p-GSK-3β Ser9, GLUT 4 and GLUT 2 expression were observed in the diabetic rats treated with RA-3. The
triterpene-treated animals also showed an improved pancreatic β-cells morphology, along with increased Cpeptide
levels. An increase in the levels of serum antioxidants such as catalase, superoxide dismutase, and
reduced glutathione was noted in the rats treated with the triterpene, while their serum levels of interleukin-6
and malondialdehyde were reduced.
Conclusions: It is apparent that RA-3 is able to improve the insulin signaling in type 1 diabetic rats. Its beta
(β)-cells protecting mechanism could be attributed to its ability to alleviate inflammation and oxidative stress
in the cells.
Description
CITATION: Mabhida, S. E., et al. 2018. A Lanosteryl triterpene from Protorhus longifolia augments insulin signaling in type 1 diabetic rats. BMC Complementary and Alternative Medicine, 18:265, doi:10.1186/s12906-018-2337-z.
The original publication is available at https://bmccomplementalternmed.biomedcentral.com
The original publication is available at https://bmccomplementalternmed.biomedcentral.com
Keywords
Hyperglycemia, Oxidative stress, Diabetes
Citation
Mabhida, S. E., et al. 2018. A Lanosteryl triterpene from Protorhus longifolia augments insulin signaling in type 1 diabetic rats. BMC Complementary and Alternative Medicine, 18:265, doi:10.1186/s12906-018-2337-z