Related Experiment Video
Updated: Jul 12, 2026
11:53
Oral Administration of Rotenone using a Gavage and Image Analysis of Alpha-synuclein Inclusions in the Enteric Nervous System
Published on: October 26, 2010
Gene therapy to prevent organophosphate intoxication
J Cowan1, C M Sinton, A W Varley
1Molecular Host Defense Laboratory, Division of Infectious Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
Toxicology and Applied Pharmacology
|May 15, 2001
Summary
Boosting serum paraoxonase (PON1) enzyme levels via gene therapy significantly protected mice from organophosphate toxicity. This approach enhances the natural defense against neurotoxins by increasing hydrolytic destruction before brain entry.
Area of Science:
- Biochemistry
- Toxicology
- Genetics
Background:
- The paraoxonase (PON1) enzyme in serum and liver acts as a natural defense against organophosphate (OP) toxins.
- Genetic variations in PON1 levels influence human susceptibility to OP-induced neurotoxicity.
Purpose of the Study:
- To investigate if augmenting serum PON1 concentrations through gene therapy can enhance protection against OP toxicity.
- To determine the efficacy of gene delivery vectors in increasing PON1 activity and mitigating OP-induced damage.
Main Methods:
- Mice were intravenously injected with recombinant adenoviruses carrying PON1-LQ or PON1-LR genes, or a control vector.
- Following gene delivery, mice were exposed to the organophosphate chlorpyrifos.
- Acetylcholinesterase (AChE) inactivation in whole brain tissue was measured to assess neurotoxicity.
Main Results:
- Recombinant viruses containing PON1 genes successfully boosted serum arylesterase activity by approximately 60%.
- Mice treated with PON1 gene therapy showed significantly less inactivation of brain acetylcholinesterase compared to controls.
- Complete protection against AChE inactivation was observed in some treated mice.
Conclusions:
- Gene therapy-mediated elevation of serum PON1 levels effectively increases the threshold for organophosphate toxicity.
- This strategy leverages hydrolytic destruction of OPs in the periphery, preventing their entry and subsequent damage to the central nervous system.
- Boosting PON1 activity via gene delivery presents a potential therapeutic approach for organophosphate poisoning.
Related Concept Videos
01:14Prevention of Further Absorption of Poison
In cases of acute poisoning, the primary objective is to prevent further absorption of the toxic substance into the body. Immediate interventions using various decontamination techniques targeting the gastrointestinal (GI) tract can achieve this. Decontamination is crucial to prevent poison from entering the systemic circulation, which involves washing affected areas with water and mild soap and removing contaminated clothing. Once external decontamination is done, attention must be turned to...
01:18Indirect-Acting Cholinergic Agonists: Mechanism of Action
Indirect-acting cholinergic agonists work by interacting with an enzyme called acetylcholinesterase (AChE) in the synaptic cleft. They can be reversible or irreversible inhibitors and have different effects on the enzyme.
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex, leading to...
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex, leading to...
01:22Indirect-Acting Cholinergic Agonists: Pharmacokinetics
Indirect-acting cholinergic agonists, or anticholinesterases, enhance the body's cholinergic activity by inhibiting acetylcholine's breakdown. They are categorized as reversible or irreversible agents based on their mechanism of action. They are further classified into short-acting, intermediate-acting, and long-acting agents based on their duration of action.
Reversible agents containing quaternary amines, such as neostigmine and edrophonium, are not easily absorbed orally because they are...
Reversible agents containing quaternary amines, such as neostigmine and edrophonium, are not easily absorbed orally because they are...
01:26Anticholinesterase Agents: Poisoning and Treatment
Anticholinesterases, also known as cholinesterase inhibitors, work by blocking the breakdown of acetylcholine, leading to its accumulation in the synaptic cleft. This accumulation indirectly enhances both muscarinic and nicotinic actions. These agents are classified as reversible or irreversible based on their mechanism of action.
Irreversible agents form a strong bond with the cholinesterase enzyme, making it inactive. The breakdown of the phosphorylated enzyme is slower than the...
Irreversible agents form a strong bond with the cholinesterase enzyme, making it inactive. The breakdown of the phosphorylated enzyme is slower than the...
01:27Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase
Phase II biotransformation reactions are essential for detoxifying and eliminating xenobiotics, including many pharmaceutical compounds. These reactions typically involve conjugation, the covalent attachment of polar endogenous groups such as glucuronic acid, sulfate, methyl, or acetyl moieties to functional groups introduced during Phase I metabolism. The resulting conjugates are more water-soluble, enabling efficient renal or biliary excretion.The major classes of Phase II enzymes include...
01:26Pharmaceutical Poisoning: Treatment Strategies
Treatment strategies for poisoning are a critical aspect of emergency medicine, focusing on preventing the absorption of toxins and enhancing their elimination. When a poisoning incident occurs, the first response is to halt exposure and decontaminate the patient, particularly through gastrointestinal (GI) methods if the poison was ingested.Gastrointestinal Decontamination Techniques:Activated charcoal is the cornerstone of GI decontamination. It works through adsorption, binding the toxin to...