Mycobacterial Toxin Induces Analgesia in Buruli Ulcer by Targeting the Angiotensin Pathways
نویسندگان
چکیده
Mycobacterium ulcerans, the etiological agent of Buruli ulcer, causes extensive skin lesions, which despite their severity are not accompanied by pain. It was previously thought that this remarkable analgesia is ensured by direct nerve cell destruction. We demonstrate here that M. ulcerans-induced hypoesthesia is instead achieved through a specific neurological pathway triggered by the secreted mycobacterial polyketide mycolactone. We decipher this pathway at the molecular level, showing that mycolactone elicits signaling through type 2 angiotensin II receptors (AT2Rs), leading to potassium-dependent hyperpolarization of neurons. We further validate the physiological relevance of this mechanism with in vivo studies of pain sensitivity in mice infected with M. ulcerans, following the disruption of the identified pathway. Our findings shed new light on molecular mechanisms evolved by natural systems for the induction of very effective analgesia, opening up the prospect of new families of analgesics derived from such systems.
منابع مشابه
A Bacterial Toxin with Analgesic Properties: Hyperpolarization of DRG Neurons by Mycolactone
Mycolactone, a polyketide molecule produced by Mycobacterium ulcerans, is the etiological agent of Buruli ulcer. This lipid toxin is endowed with pleiotropic effects, presents cytotoxic effects at high doses, and notably plays a pivotal role in host response upon colonization by the bacillus. Most remarkably, mycolactone displays intriguing analgesic capabilities: the toxin suppresses or allevi...
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Organisms in the genus Mycobacterium cause a variety of human diseases. One member of the genus, M. ulcerans, causes a necrotizing skin disease called Buruli ulcer. Buruli ulcer is unique among mycobacterial diseases in that the organisms at the site of infection are extracellular and there is little acute inflammatory response. Previous literature reported the presence of a toxin in the cultur...
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Introduction: Mycobacterium ulcerans is the etiological agent of Buruli ulcer (BU) the third most common mycobacterial infection in humans after tuberculosis and leprosy. BU is now considered by the WHO to be an emerging infection of major concern. M. ulcerans produces mycolactone toxin, which is required for the organism’s virulence. Mycolactone destroys tissue and suppresses host immune respo...
متن کاملMycolactone-mediated neurite degeneration and functional effects in cultured human and rat DRG neurons
BACKGROUND Mycolactone is a polyketide toxin secreted by the mycobacterium Mycobacterium ulcerans, responsible for the extensive hypoalgesic skin lesions characteristic of patients with Buruli ulcer. A recent pre-clinical study proposed that mycolactone may produce analgesia via activation of the angiotensin II type 2 receptor (AT2R). In contrast, AT2R antagonist EMA401 has shown analgesic effi...
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BACKGROUND The neglected tropical disease Buruli ulcer (BU) caused by Mycobacterium ulcerans is an infection of the subcutaneous tissue leading to chronic ulcerative skin lesions. Histopathological features are progressive tissue necrosis, extracellular clusters of acid fast bacilli (AFB) and poor inflammatory responses at the site of infection. After the recommended eight weeks standard treatm...
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ورودعنوان ژورنال:
- Cell
دوره 157 شماره
صفحات -
تاریخ انتشار 2014