homoanatoxina

Homoanatoxin, commonly referred to as homoanatoxin-a, is a neurotoxic alkaloid produced by certain freshwater cyanobacteria and found in cyanobacterial blooms. It is closely related to anatoxin-a and is considered part of the family of cyanotoxins associated with rapidly arising neurological symptoms. Homoanatoxin-a has been detected in blooms in lakes and reservoirs worldwide, often alongside other cyanotoxins such as anatoxin-a.

Mechanism and effects: Homoanatoxin-a acts as a potent agonist of nicotinic acetylcholine receptors at neuromuscular junctions and related neural sites. By causing persistent receptor activation, it disrupts normal synaptic transmission, leading to overstimulation, muscle fasciculations, weakness, and can progress to paralysis. The onset of symptoms can be rapid, typically within minutes to a few hours after exposure, and death may result from respiratory failure if ventilatory function is compromised. The toxin is a small, lipophilic molecule that can accumulate in the environment and in organisms that come into contact with contaminated water.

Exposure and risk: Humans and animals can be exposed through ingestion of contaminated water or during activities in cyanobacteria-rich waters. Risk is elevated during algal blooms, and exposure can occur with drinking water supplies or recreational water use. Because toxin levels can vary widely, monitoring of water bodies is important in affected regions.

Detection and management: Detection is typically accomplished by chemical analysis of water or biological samples using methods such as liquid chromatography–mass spectrometry. There is no widely available specific antidote for homoanatoxin-a; treatment is supportive, with emphasis on securing the airway and providing respiratory support as needed. Public health measures focus on bloom monitoring and issuing advisories to minimize exposure.