Hormones & Vertigo

State of the Art

Vestibular disorders of peripheral origin constitute 1.9% of all medical prescriptions for all ages, and 3% for those over 50 (1). They also represent nearly 1% of hospital emergencies (2). Despite this high prevalence, diagnostic and therapeutic approaches against vestibular disorders are still insufficiently developed. There is now a strong medical need for diagnostic tools that make it possible to discriminate between the different types of vestibular disorders, and for adapted pharmacological approaches that make it possible to effectively reduce the attack of vertigo. The interaction between the endocrine system and the vestibular system remains virtually unexplored to date, despite numerous observations in humans and animals that report a direct link between the two systems (3). We know, for example, that BPPV is very predominantly found in postmenopausal women or during menstruation, that steroids support both the facilitating and deleterious effects of stress on vestibular compensation, or that hypersensitivity to vasopressin at the level tissue from the inner ear could be involved in the pathogenesis of Ménière’s disease. It has also been shown that steroid hormones, as well as amines and peptides, directly affect the peripheral vestibular system via specific receptors expressed in the tissues of the inner ear.

(1) Hülse R, Biesdorf A, Hörmann K, Stuck B, Erhart M, Hülse M, Wenzel A. Peripheral Vestibular Disorders: An Epidemiologic Survey in 70 Million Individuals. Otol Neurotol. 2019 Jan;40(1):88-95. doi: 10.1097/MAO.0000000000002013.

(2) Newman-Toker DE, Cannon LM, Stofferahn ME, Rothman RE, Hsieh YH, Zee DS. Imprecision in patient reports of dizziness symptom quality: a cross-sectional study conducted in an acute care setting. Mayo Clin Proc. 2007; 82(11):1329–1340.

(3) Seemungal BM, Gresty MA, Bronstein AM. The endocrine system, vertigo and balance. Curr Opin Neurol. 2001;14(1):27-34. doi:10.1097/00019052-200102000-00005

State of the Question

Different questions are now being asked about:

The functional role that circulating hormones can exert in non-pathological conditions, on the peripheral and central parts of the vestibular system.
The inducing role of vestibular dysfunctions that certain hormones can exert by their variation.
Can circulating hormones behave as biomarkers of certain types or stages of vestibular pathologies?
Can we demonstrate the direct participation of certain hormones in the induction of vertigo attacks and / or vertiginous syndrome?

Objectives of the Team

The projects and objectives of the TT are multiple and should be prioritized on the basis of work and funding capacities:

Identify in rodents and humans the hormone receptors expressed in peripheral and central vestibular systems
Highlight their modulating role in the normal function of the vestibular system
Establish the hormonal profile of vertigo and unstable patients in crisis and at a distance from it
Look for hormonal biomarkers of the different types and stages of vestibular damage
Develop specific diagnostic kits for the different types and stages of vestibular disorders
Look for the involvement of certain hormones in the pathological function of the vestibular system
Suggest pharmacological countermeasures to the deleterious action of these hormonal factors

Organisation of the Team

The team Hormones & Vertiges is organized around scientists with skills related to the team’s research projects (neuroscience, endocrinology, biochemistry, cellular and molecular biology, electrophysiology), and clinicians specialized in the management of the dizzying and unstable patient. The team coordinated by C Chabbert (UMR7291, Marseille) was launched at the beginning of October 2020. Dr R El Khiati has operational responsibility as part of his doctoral thesis under the joint responsibility of Drs C Chabbert and S Besnard. Regular exchanges between team members are carried out as part of the projects launched by the team. Various communication events will be organized via the GDR Vertige networks. A team activity report will be published at the end of the year.

Composition of the team

Researchers

50 %

Clinicians

33 %

Students

17 %

Team Members

BESNARD S (Univ Basse Normandie & UMR7291, Marseille)

CHABBERT C (UMR7291, Marseille) -Team leader

EL KHIATI R (UMR7291, Marseille) -Operational manager

ELZIERE M (Hôpital Européen, Marseille)

HAUTEFORT C (Hôpital Lariboisière, APHP, Paris)

TIGHILET B (UMR7291, Marseille)

WECKEL A (CHU Purpan, Toulouse)

Projects under development

Screening of hormone receptor expression in the vestibular system

A doctoral thesis projects will start in 2021 in order to characterize the hormone receptors expressed in the vestibular system of mammals. The thesis project will be offered at the start of the Fall 2021 school year with the aim of recruiting a three-year student on this topic. The main objectives of this project will be to: i) study the tissue expression of different families of hormone receptors in the peripheral and central areas of the vestibular system. This study will be carried out using descriptive approaches combining molecular biology (TRPCR, RNA Seq) and histology (immunocytochemistry, electron microscopy); ii) to study the functional impact of hormonal modulations on vestibular function (organotypic cultures, co-cultures, in vitro and in vivo pharmacology, vestibular behavior).

Clinical study of the link between hormonal profile and vestibulopathies

The “Hormone and Vertigo” clinical study will bring together several ENT departments of French Hospitals and will be coordinated by the Pathophysiology and Therapy of Vestibular Disorders team at UMR7291 in Marseille (C Chabbert and S Besnard). It should make it possible to identify new clinical biomarkers in the diagnosis of vestibular disorders and to develop new diagnostic systems for vestibular pathologies of peripheral origin. The aim of the study is to seek direct evidence of the involvement of circulating hormones in the genesis and development of major vestibular disorders. For this, we propose to set up a multicenter clinical study in order to establish a hormonal profile of patients in several types of vestibular pathologies or pathogenic situations (BPPV; Chronic instabilities / PPPD, poor central compensation, etc.); Acute Peripheral Vestibulopathies (neuritis, labyrinthitis …); Recurrent peripheral vestibulopathies (Ménière’s disease, vestibular migraine, perilymphatic fistulas …); Healthy volunteers during tests (PEO, Caloric, Galvanic stimulation). The challenge will be to harvest blood samples at the time of the vertigo attack and at a distance from it in the same patients, and to perform assays of different circulating hormones in order to identify biomarkers that discriminate types of vertiginous pathologies. Several hormones from different systems will be sought : stress hormones, gonadotropic hormones, hormone nes of circadian rhythms and sleep … The kinetics of variation of these hormones will be correlated with the clinical expression of the different types of vestibular disorders.