Emerging drugs for common conditions of sleepiness: obstructive sleep apnea and narcolepsy

Prospecting for para-endogenous anxiolytics in the human microbiome: Some promising pathways

The gut microbiome is a vast, variable, and largely unexplored component of human biology that sits at the intersection of heritable and environmental factors, and represents a rich source of novel chemistry that is already known to be compatible with the human body. This alone would make it a promising place to search for new therapeutics, but recent work has also identified gut microbiome abnormalities in patients with a number of psychiatric disorders, including anxiety disorders-suggesting that not only treatments, but cures may lie therein. Here, we'll discuss two known "para-endogenous" anxiolytics-γ-hydroxybutyrate and the neurosteroid allopregnanolone-which have recently been discovered to be produced by the microbiome.

Peroxisome Proliferator-Activated Receptor agonists and antagonists: an updated patent review (2020-2023)

INTRODUCTION

The search for novel compounds targeting Peroxisome Proliferator-Activated Receptors (PPARs) is currently ongoing, starting from the previous successfully identification of selective, dual or pan agonists. In last years, researchers' efforts are mainly paid to the discovery of PPARγ and δ modulators, both agonists and antagonists, selective or with a dual-multitarget profile. Some of these compounds are currently under clinical trials for the treatment of primary biliary cirrhosis, nonalcoholic fatty liver disease, hepatic, and renal diseases.

AREAS COVERED

A critical analysis of patents deposited in the range 2020-2023 was carried out. The novel compounds discovered were classified as selective PPAR modulators, dual and multitarget PPAR agonists. The use of PPAR ligands in combination with other drugs was also discussed, together with novel therapeutic indications proposed for them.

EXPERT OPINION

From the analysis of the patent literature, the current emerging landscape sees the necessity to obtain PPAR multitarget compounds, with a balanced potency on three subtypes and the ability to modulate different targets. This multitarget action holds great promise as a novel approach to complex disorders, as metabolic, inflammatory diseases, and cancer. The utility of PPAR ligands in the immunotherapy field also opens an innovative scenario, that could deserve further applications.

[Differential diagnosis of hypersomnia in surgical sleep medicine-more than just sleep apnea!]

Otorhinolaryngologists play a vital role in the management of patients with obstructive sleep apnea (OSA) in Germany, particularly with regards to outpatient diagnostics as well as conservative and surgical treatment of patients with intolerance to ventilation therapy. Although establishment of differential indications for surgical therapy and performance of additional preoperative drug-induced sleep endoscopy in patients with sleep-disordered breathing are among the core competencies of otorhinolaryngologists, differential diagnostic considerations and detection of comorbid sleep disorders can be challenging, particularly for those without extensive sleep medicine training and experience. However, detection of comorbid sleep disorders is of particular importance when permanent surgical treatment is considered. Daytime sleepiness is the typical leading symptom of OSA; nevertheless, other disorders of hypersomnolence need to be considered in these patients and can easily be overlooked. This may lead to inadequate indications for surgical treatment. Based on two case reports, narcolepsy is presented as a comorbid disorder and differential diagnosis in patients with OSA.

Impact of histaminergic H3 receptor antagonist on hypoglossal nucleus in chronic intermittent hypoxia conditions

RATIONALE

The hypoglossal nucleus (HN) controls the movement of the genioglossus (GG) muscle whose dysfunction leads to airway occlusion and occurrence of obstructive sleep apnea (OSA). Histamine produced by the tuberomammillary nucleus (TMN) has a potent excitatory action on GG muscle activity.

OBJECTIVES

The aim of the study was to investigate the role histaminergic neurons play in the regulation of the genioglossus.

METHODS

C57BL/6 mice were exposed to chronic intermittent hypoxia (CIH) for 3 weeks to resemble OSA. The histamine H3 receptor (H3R) antagonist ciproxifan was applied to increase histamine in the brain. Histamine levels and GG activity were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and electromyogram (EMG) separately. Neuronal activity and repair ability of the HN and TMN and key proteins of histamine were analyzed by immunohistochemistry and western blots.

RESULTS

Significant decline of histamine level and GG activity of the HN and TMN induced by CIH exposure could be ameliorated by ciproxifan. Application of ciproxifan could also partly reverse the decline of the histidine decarboxylase (HDC) by CIH.

CONCLUSIONS

This investigation studied the impacts of ciproxifan on the HN and TMN in CIH conditions and revealed that the negative effects on the HN and TMN caused by CIH could be partly ameliorated by ciproxifan, which might open new perspectives for the development of pharmacological treatment for OSA.

Understanding the burden of illness of excessive daytime sleepiness associated with obstructive sleep apnea: a qualitative study

BACKGROUND

Obstructive sleep apnea (OSA) is associated with excessive daytime sleepiness (EDS), which may go undiagnosed and can significantly impair a patient's health-related quality of life (HRQOL). This qualitative research examined timing and reasons patients sought medical care for their EDS and OSA symptoms, and the impact of EDS on HRQOL.

METHODS

Focus groups were conducted in 3 US cities with 42 participants currently experiencing EDS with OSA. Transcripts were coded and analyzed using an adapted grounded theory approach common to qualitative research.

RESULTS

Over three-fifths of study participants (n = 26, 62%) were currently using a positive airway pressure (PAP) or dental device; one-third (n = 14, 33%) had previously used a positive airway pressure (PAP) or dental device, and the remainder had either used another treatment (n = 1, 2%) or were treatment naïve (n = 1, 2%). Twenty-two participants (52%) reported experiencing OSA symptoms for ≥1 year, with an average duration of 11.4 (median 8.0, range 1-37) years before seeking medical attention. Several (n = 7, 32%) considered their symptoms to be "normal," rather than signaling a serious medical condition. Thirty participants (71%) discussed their reasons for ultimately seeking medical attention, which included: input from spouse/partner, another family member, or friend (n = 20, 67%); their own concern about particular symptoms (n = 7, 23%); and/or falling asleep while driving (n = 5, 17%). For all 42 participants, HRQOL domains impacted by EDS included: physical health and functioning (n = 40, 95%); work productivity (n = 38, 90%); daily life functioning (n = 39, 93%); cognition (n = 38, 90%); social life/relationships (n = 37, 88%); and emotions (n = 30, 71%).

CONCLUSIONS

Findings suggest that patients may be unaware that their symptoms could indicate OSA requiring evaluation and treatment. Even following diagnosis, EDS associated with OSA can continue to substantially affect HRQOL and daily functioning. Further research is needed to address diagnostic delays and unmet treatment needs for patients with EDS associated with OSA.

Investigational therapies for the treatment of narcolepsy

INTRODUCTION

Narcolepsy is a chronic sleep disorder characterized by a pentad of excessive daytime sleepiness (EDS), cataplexy, sleep paralysis, hypnagogic/hypnopompic hallucinations, and disturbed nocturnal sleep. While non-pharmacological treatments are sometimes helpful, more than 90% of narcoleptic patients require a pharmacological treatment. Areas covered: The present review is based on an extensive Internet and PubMed search from 1994 to 2017. It is focused on drugs currently in development for the treatment of narcolepsy. Expert opinion: Currently there is no cure for narcolepsy, with treatment focusing on symptoms control. However, these symptomatic treatments are often unsatisfactory. The research is leading to a better understanding of narcolepsy and its symptoms. New classes of compounds with possible applications in the development of novel stimulant/anticataplectic medications are described. H3 receptor antagonists represent a new therapeutic option for EDS in narcolepsy. JZP-110, with its distinct mechanism of action, would be a new therapeutic option for the treatment of EDS in the coming years. In the future, hypocretin-based therapies and immune-based therapies, could modify the clinical course of the disease. However, more information would be necessary to completely understand the autoimmune process and also how this process can be altered for therapeutic benefits.