Effect of Natural Product Extracts on Lipoxygenase, Cyclooxygenase, and Protein Tyrosine Phosphatase 1β

Abstract

The purpose of this research project is to examine the inhibition of enzymes linked to inflammation and associated diseases by plants traditionally as anti-inflammatory medicines: Tussilago farfara, Grindelia squarrosa, and Uritca dioica. Arachidonic acid is metabolized in the body through two main metabolic pathways with the enzymes: cyclooxygenases (COX) and lipoxygenases (LOX). Elevated levels of prostanoids and leukotrienes, products of the two respective pathways, have been linked to inflammatory diseases. Finding a dual inhibitor of COX and LOX is promising in preventing the inflammation and diseases that are linked to the overproduction of both pathways while minimizing the side effects associated with inhibition of individual pathways. Furthermore, the enzyme protein tyrosine phosphatase 1β (PTP1β) is linked between inflammation and metabolic disease through the leptin receptor-associated Janus Kinase (JAK). PTP1β is a negative regulator of insulin and leptin receptors thus being explored as a possible therapeutic for type II diabetes and obesity. Crude methanolic extracts of Tussilago farfara, Grindelia squarrosa, and Urtica dioica were taken to approximate the plants' components released in the body upon consumption. The bioactivities of the standardized extracts were then determined using enzymatic assay kits for COX I and II, LOX, and PTP1β. T. farfara is the strongest LOX inhibitor at 60% inhibition of 15-LOX, followed by U. dioica and G. squarrosa at 45% and 39%, respectively. Studies for COX I and II as well as PTP1β inhibition are ongoing, and the results will be presented.