Electronic Thesis and Dissertation Repository

Thesis Format

Monograph

Degree

Master of Science

Program

Chemistry

Supervisor

Luyt, Len

2nd Supervisor

Ramachandran, Rithwik

Co-Supervisor

Abstract

Osteoarthritis (OA) is the most common form of arthritis in the world and develops in the joints resulting in inflammation. A defining characteristic of OA is the gradual destruction of cartilage coupled with an increase in proteolytic enzyme activity. The activation proteinase activated receptors (PARs), a type of G-protein coupled receptors (GPCRs), has been found to increase joint inflammation in OA. Due to the irreversible action of proteolysis, proteolytic activity is highly regulated within cellular systems. The expression of matrix metalloproteases (MMPs) and serine proteases have been identified in OA. We present a novel activity-based probe (ABP) that covalently binds to MMPs in OA synovial fluid. A previously reported serine ABP was also synthesized and was found to target trypsin-like serine proteases in OA synovial fluid. These probes are useful chemical tools that can identify active proteases in OA.

Summary for Lay Audience

Osteoarthritis (OA) is the most common form of arthritis in the world. It can affect all joints but most commonly effects the knees and hips resulting in inflammation, pain, and stiffness. More than any other disease, OA impacts one’s ability to walk and is the most common reason for total hip and total knee replacement. Most OA patients are given symptomatic treatment due to an absence of drugs that halt structural damage to the joints. It has been found that enzymes capable of breaking down peptides (proteases) activate certain receptors in the body and increase inflammation and cartilage degradation. The evidence of the existence of these proteases in OA have been found but the identity of the proteases activating the receptors is unknown. Chemical tools called activity based probes (ABPs) can help identify the activating proteases. They work by forming a permanent bond to the active protease which can then be isolated from a biological sample, like OA knee synovial fluid. The probe bound to the proteases can then be identified by checking the weight of the protease against a database of known proteases. The work in this thesis demonstrates the creation of a new ABP to target matrix metalloproteases 2 and 9, which have been found to exist in OA. In this work, a previously made probe to target a specific serine protease was also created. The ability of these probes to bind to active proteases in standards and OA synovial fluid will be discussed.

Available for download on Tuesday, September 01, 2026

Share

COinS