Targeting the purinergic system for disease-modification in epilepsy

Project Information

EpiPurines

Grant agreement ID: 101032321

DOI

10.3030/101032321

Project terminated on 5 November 2024

EC signature date 9 March 2021

Start date 1 April 2022

End date 1 August 2025

Funded under

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Total cost

€ 257 561,28

EU contribution

€ 257 561,28

Coordinated by

ROYAL COLLEGE OF SURGEONS IN IRELAND
Ireland

Periodic Reporting for period 2 - EpiPurines (Targeting the purinergic system for disease-modification in epilepsy)

Reporting period: 2024-04-01 to 2025-03-31

Summary of the context and overall objectives of the project

Epilepsy, a chronic neurological disorder affecting over 80 million people worldwide, poses significant health concerns. Approximately 30% of epilepsy cases are acquired, resulting from precipitating injuries such as traumatic brain injury (TBI). TBI is a leading cause of injury-related death and disability globally, with devastating consequences for patients and their families. Despite the development of over 30 anti-seizure medications (ASMs), approximately 30% of patients experience uncontrolled seizures.

The EpiPurines project aims to test the disease-modifying potential of targeting the purinergic system, specifically adenosine and ATP-gated P2X7 receptors. By using mouse models of epilepsy and combinatory pharmacological treatments, this project seeks to prevent or ameliorate epilepsy development, addressing a critical unresolved health concern with significant implications for improving quality of life for those affected.

Key Objectives:
Objective 1 (M1-12, RU): Determine the anti-epileptogenic properties of increased adenosine in a mouse model of TBI. In our first objective we will test whether adenosine-based treatment using highly specific ADK inhibitors prevents/ameliorates the development of epilepsy in a mouse model of post-traumatic epilepsy (Work package (WP) 1).
Outcome: this study showed that ADK and DNA methylation inhibitors are not efficient to prevent seizures in a mouse model of CCI-induced PTE. A possible limitation may be associated with the duration of the treatment, suggesting that these inhibitors do not present a long-lasting effect, requiring a longer treatment window to, eventually, present a reduction in spontaneous seizures in mice with PTE.

Objective 2 (M 13-24, RU): Evaluate the disease-modifying potential of a combinatory treatment based on the simultaneous targeting of the ATP-gated P2X7 receptor and ADK during epileptogenesis and epilepsy. In our second objective we will test whether simultaneous targeting of the ATP-gated P2X7 receptor and ADK will provide a synergistic effect in preventing the development of epilepsy and revert chronic epilepsy. To this end, we will use highly specific P2X7 agonists (provided by our collaborators Janssen R&D & Affectis) in combination with highly specific strategies to block ADK (e.g. inhibitors, ADK-targeting gene therapy vectors) (WP2).
Outcome: The results showed a small trend to reduce the number of HPDs in mice treated with 5-ITU-JNJ565 when compared with KA-veh mice, and a significant reduction in the number of HPDs when compared with the mice treated with JNJ565-5-ITU 4 weeks after KA injection.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

This section summarizes activities from April 2022 to October 2024, focusing on WPs 1 and 2. WP3 was not initiated during this timeframe.

During this period, I participated in three conferences, presenting my research via:
- 2 oral talks;
- 1 poster presentation;

WP 1: Determine the anti-epileptogenic properties of increased adenosine in a mouse model of Traumatic Brain Injury (TBI) (RU, M1-12). - Completed.
Main results:
i) Progressive increases in ADK expression in conjunction with astrogliosis following CCI;
ii) Mice overexpressing ADK-L presented an increase in brain excitability following a KA challenge 28 days post-CCI, while ADKΔNeuron mice (lack ADK in neurons) displayed lower brain excitability following a KA challenge 28 days after CCI.
iii) CCI mice transiently treated with either ADK inhibitor 5-ITU or ADK-L inhibitor MRS4203 showed increased brain excitability in the EEG total power 28 days post-CCI, and an increase in hippocampal gliosis.
iv) ADK inhibitor 5-ITU was not able to protect against the development of spontaneous seizures, while DZP, an anti-seizure medication used in clinical to stop seizures, reduced the number of spontaneous seizures 12 weeks after the initial injury when compared to CCI-vehicle group.


WP 2: Evaluate the therapeutic potential of blocking ATP-gated receptors and incrementing adenosine signalling during epileptogenesis (RU, M13-24). - 50% completed.
Main results:
i) Mice treated with 5-ITU-JNJ565 showed a trend towards reduced hippocampal paroxysmal discharges (HPDs) compared to KA-veh mice.
ii) Significant reduction in HPDs occurred when comparing 5-ITU-JNJ565 to JNJ565-5-ITU treatments, 4 weeks post-KA injection.
iii) Sequential treatment (5-ITU → JNJ565) proved more effective than reverse sequence in attenuating spontaneous seizure development.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Epilepsy is a chronic neurological disorder that affects more than 80 million people worldwide, and over 3 million adults in the United States alone. Approximately 30% of all epilepsies are acquired, implying that those epilepsies are caused by a precipitating injury, such as traumatic brain injury (TBI). Despite the development of more than 30 anti-seizure medications, seizures remain uncontrolled in around 30% of patients. Therefore, there is an urgent need for the development of therapeutic strategies capable of preventing PTE and its progression.

Prior research from Dr.Boison’s lab demonstrated that epilepsy and its progression can be attenuated by therapeutic adenosine (ADO) augmentation to the brain. In the same line, prior research from Dr. Engel’s lab have shown the anti-convulsive and anti-epileptogenic potential of targeting P2X7R. P2X7 antagonism not only reduced seizure severity and brain damage during status epilepticus but also decreased seizure frequency and neuroinflammation during epilepsy.

This project pioneers innovative therapeutic strategies for post-traumatic epilepsy (PTE), surpassing existing treatments. By targeting the purinergic system, specifically P2X7R and adenosine, we anticipate significant advancements such as:
1) Development of preventative treatments reducing seizure frequency and severity;
2) Enhanced understanding of ADK-L's role in PTE;

I have successfully demonstrated an important role of ADK-L in PTE. Using a genetic approach I have reported that overexpressing ADK-L potentiates the development of evoked seizures, while inhibition of ADK-L not only reduces the development of evoked seizures, but also reduces the duration of these seizures. Moreover, combination treatment of 5-ITU followed by JNJ565 attenuated the development of spontaneous seizures in a mouse model of acquired epilepsy.

This project generated robust data, significantly advancing our understanding of epilepsy pathophysiology. Therefore, these results have significant implications for the development of innovative epilepsy treatments.
Potential impacts of this work:
i) Improved quality of life for TBI/epilepsy patients;
ii) Expanded treatment options for service members, athletes and civilians;
iii) Reduced socioeconomic burden of epilepsy;
iv) Enhanced understanding of epilepsy pathophysiology.

image from a poster presented at AES conference