Discovery and Development of a Novel mPGES-1/5-LOX Dual Inhibitor LFA-9 for Prevention and Treatment of Chronic Inflammatory Diseases
Nagendra Sastri Yarla, Gopal Pathuri, Hariprasad Gali, S. Terzyan, Janani Panneerselvam, Parthasarathy Chandrakesan, Luciana Scotti, Courtney W. Houchen, Venkateshwar Madka, Chinthalapally V. Rao
Abstract
Background: Non-steroidal anti-inflammatory drugs, cyclooxygenase (COX)-2 selective inhibitors, have been explored for prevention and treatment of several inflammatory chronic conditions including arthritis, and cancer. However, the long-term use of these drugs is associated with gastrointestinal, renal, and cardiovascular side effects. Later, COX/5-lipoxygenase (5-LOX) dual inhibitors (eg, licofelone) have been developed but did not enter into the market from the clinical trails due to COX-1/2 inhibition-associated side effects. Hence, targeting microsomal prostaglandin E synthase-1 (mPGES-1) and 5-LOX can be an ideal approach while sparing COX-1/2 activities for development of the next generation of anti-inflammatory drugs with better efficacy and safety. Materials and Methods: In silico (molecular modelling) studies were used to design a mPGES-1/5-LOX dual inhibitory and COX-1/2 sparing lead molecule licofelone analogue-9 (LFA-9) by modifying the pharmacophore of licofelone. In vitro cell-free enzymatic (mPGES-1, 5-LOX, COX-1/2) assays using fluorometric/colorimetric methods and cell-based assays (LPS-induced PGE 2 , LTB 4 , and PGI 2 productions from macrophages) using ELISA technique, isothermal calorimetry, and circular dichroism techniques were performed to determine the mPGES-1/5-LOX inhibitory efficacy and selectivity. Anti-inflammatory efficacy of LFA-9 was evaluated using a carrageenan (inflammogen)-induced rat paw edema model. Infiltration/expression of CD68 immune cells and TNF-α in paw tissues were evaluated using confocal microscope and immunoblot analysis. Anti-cancer effect of LFA-9 was evaluated using colon spheroids in vitro. Results: LFA‐9 inhibited mPGES-1/5-LOX and their products PGE 2 and LTB 4 , spared COX-1/2 and its product PGI 2 . LFA‐9 bound strongly with human mPGES‐1/5‐LOX enzymes and induced changes in their secondary structure, thereby inhibited their enzymatic activities. LFA-9 inhibited carrageenan-induced inflammation (70.4%) in rats and suppressed CD68 immune cell infiltration ( P ≤ 0.0001) and TNF-α expression. LFA-9 suppressed colon tumor stemness (60.2%) in vitro through inhibition of PGE 2 (82%) levels. Conclusion: Overall study results suggest that LFA-9 is a mPGES-1/5-LOX dual inhibitor and showed anti-inflammatory and colorectal cancer preventive activities, and warranted detailed studies. Keywords: mPGES-1/5-LOX dual inhibitor, LFA-9, drug design, anti-inflammatory agent, cancer chemoprevention