Design, Synthesis and Biological Evaluation of Novel Chalcone-based Fibrates as Novel PPAR-a Agonists

Project leaders

Francesca Sciandra, Iman Ahmed Youssef Ghannam

Agreement

EGITTO - NRC - National Research Centre of Egypt

Call

CNR/NRC biennio 2018-2019 2018-2019

Department

Chemical sciences and materials technology

Thematic area

Chemical sciences and materials technology

Status of the project

New

Research proposal

The project will be focused on the synthesis of novel chalcone-based fibrates to use as agonist of the peroxisome proliferator-activated receptor isoform alpha (PPAR-a). The new drugs will have a simple structure easy to synthesize from cheap raw material. The activities of the NRC and CNR laboratories will be integrated to optimise the outcome of this research program. The NRC Unit has a strong tradition in the synthesis of novel active molecules, while the Italian Unit has a strong biochemical and cellular expertise that is required for the biological evaluation of the novel compounds.

Background:
Hypertriglyceridemia and hypercholesterolemia are two major factors associated with cardiovascular diseases (CVD), which are the leading cause of mortality worldwide [1]. PPAR-a, one of the peroxisome proliferator-activated receptor isoforms, is mainly found in liver, kidney, heart, muscle, and adipose tissue. It plays a critical role in fatty acid oxidation and lipoprotein metabolism [2,3]. Therefore, PPAR-a is an important target for the treatment of dyslipidemia. PPARg, another very widely investigated PPAR subtype, has been shown to be an important regulator of target genes involved in lipid metabolism [4]. In addition, oxidative stress is an important factor in the development of vascular damage [5]. The involvement of reactive oxygen species has been found to be a major causative factor for peroxidative damage to lipoproteins present in the blood, which is responsible for the initiation and progression of atherosclerosis [6]. On the basis of the underlying pathophysiological processes of CVD, therapeutic agents possessing both antihyperlipidemic and antioxidant activities are an ideal choice for the treatment of CVD and the development of such agents has been the focus of much research in recent years.
Fibrates, such as clofibrate, fenofibrate and gemfibrozil, have been used clinically for many years for the treatment of dyslipidemia to reduce cardiovascular risk [7]. Although it has been demonstrated that fibrates exert their effects by activating PPARa [8], most of them show weak agonist activities and some of them even display severe adverse effects [4,9]. Therefore, the development of more effective PPARa agonists is urgently needed. On the other hand, chalcones are important class of compounds that presents in many naturally occurring products. Their pharmaceutical potential is due to their radical-scavenging [10], antitumor [11], anti-inflammatory [12] and neuro-protective properties [13]. Furthermore, literature survey revealed that hybrid compounds obtained by a combination of the classical fibrate and chalcone exhibited significant hypolipidemic activities.

Experimental Strategy:
Novel chlacone-based fibrates will be prepared by the NRC-unit using well defined protocols. The novel compounds will be tested in vitro and in vivo by the CNR. For in vitro tests, hepatoblastoma cell line HepG2 will be used.The modulation of PPAR transcriptional activity by the synthetic molecules will be analysed using PPAR-a transactivation assays and TR-FRET PPARa competitive binding assays using commercial kits.
In vivo studies will be conducted in rats for the detemination of antihyperlipedimc activity induced by triton WR-1339 (acute model) and high fat diet (chronic model).Rats will be treated with tested compounds and standard fibrate. Plasma will be used for analysis of total cholesterol (TC), triglycerides (TG) and phospholipids (PL) by standard enzymes. Histopathological study of the rat liver of all groups will be performed.
The expression of PPAR-a gene will be also assessed in cells and in rat livers of using real-time PCR.

Expected Outcomes
1. Antihyperlipidemic drugs are one of the powerful candidates, which currently attract much attention from many pharmaceutical companies. Therefore, this project will make significant contribution to the development of the fields both in academia and pharmaceutical industry.
2. Our strategy is focused on innovation of new drugs having simple structure and derived from cheap raw material. Therefore, the drug products could be available for poor people when totally synthesized by Egyptian pharmaceutical companies.
3.The results of this project may add benefit in the treatment of cardiovascular diseases one of the most common causes of death in modern societies and also reduce cost in public health.
4. The novelty of this work and the expected hypolipidemic activity of the novel compounds may lead us to get patents as well as publishing research articles in high impact peerreviewed international journals with excellent reputation.

Mode of Co-operation:

1. The chemistry part (design and synthesis of the compounds) and the biology part in vivo assay in the acute model will be performed by the Egyptian research team at the National Research Centre (NRC), Cairo, Egypt.

2-The biology part (in vitro, in vivo (chronic model) assays and gene expression) will be carried out by the biologists in the Egyptian and Italian research teams at the Institute Chemistry of Molecular Recognition, CNR, Roma, Italy.

References
[1] Z. Liu, M. Hu, P. Chan, B. Tomlinson, Expert Opin. Inv. Drug. 24, (2015), 611-621.
[2] M.C. Rodrigo, B.M. Poblete, G.O. Gonzalez, M.E. Leiva, E.V. Mujica, A.C. Aranguez, P. Ivan, Mol. Med. Rep. 1, (2008), 317-324.
[3] I. Ahmed, K. Furlong, J. Flood, V.P. Treat, B.J. Goldstein, Am. J. Ther. 14, (2007), 49-62.
[4] C. Pirat, A. Farce, N. Lebègue, N. Renault, C. Furman, J. Med. Chem. 55, (2012), 4027-4061.
[5] R. Stocker, J.J. Keaney, Physiol. Rev. 84, (2004), 1381-1478.
[6] T. Inoue, M. Hayashi, K. Takayanagi, S. Morooka, Atherosclerosis 160, (2002), 369-376.
[7] A.S. Wierzbicki, A. Viljoen, Expert Opin. Pharmacother. 15, (2014), 2673-2680.
[8] D.J. Mangelsdorf, R.M. Evanst, Cell 83, (1995), 841-850.
[9] T.M. Willson, P.J. Brown, D.D. Sternbach, B.R. Henke, J. Med. Chem. 43, (2000) 527-550.
[10] A. Detsi, M. Majdalani, C.A. Kontogiorgi

Research goals

The wide objective of this study is to design and synthesize novel PPAR-a agonists. Our target will be achieved using molecular docking technique using the structure of fibrates as lead compounds.
This will be achieved by;
a-Design novel PPARa agonists based on the crystal structure of bound to PPAR-± using molecular docking technique. It is planned to study the effect of the structural modifications on the interaction with the active site of PPARa receptor (NRC-unit).
b-Depending on the results of the molecular modeling study, target compounds will be synthesized by ordinary organic synthesis (NRC-unit).
c-Experimental evaluation of the newly synthesized compounds for their in vitro PPARa agonistic activity (transactivation and ligand binding assays). This will be followed by comparing between the theoretical results obtained from the molecular modeling with the practical results (CNR-unit).
d-Promising compounds will be subjected to determination of in vitro antihyperlipidemic activity using triton WR-1339 (acute model) and high fat diet (chronic model) and hereafter histopathology of the liver will be also performed (NRC and CNR-unit).
e-Western blot analysis for the total PPARa protein, RNA extraction and real time PCR analysis will be also done using sample from cells and rat livers (CNR-unit).

Last update: 30/04/2024