Slaapstoornis Wetenschap

PER3 VNTR polymorphism in Multiple Sclerosis: A new insight to impact of sleep disturbances in MS.

Mult Scler Relat Disord. 2017 Oct;17:84-86

Authors: Golalipour M, Maleki Z, Farazmandfar T, Shahbazi M

Abstract
BACKGROUND: Multiple Sclerosis (MS) is a degenerative disease of central nervous system caused by an immune response against the myelin. About half of MS patients suffers from sleep disturbances. The circadian clock genes such as PER3 controls circadian rhythm and sleep. Due to the role of PER3 in sleep disturbances and regulation of immune response, it is possible that PER3 dysregulation increase risk of MS disease.
METHODS: Study groups included 160 MS patients and 160 healthy volunteers. PER3 VNTR polymorphism was evaluated by PCR method. The genotypic and allelic distribution analyzed by chi square test.
RESULTS: There was a significant association between genotype PER3(4/4), and 4-repeat allele with MS disease (p = 0.014 and p < 0.001 respectively). The association analysis of PER3 VNTR polymorphism with gender status among MS group, and MS onset showed that there was a significant correlation between PER3(4/4) genotype with female gender and early onset of MS disease (p = 0.033 and p = 0.028 respectively).
CONCLUSION: Our data suggest that, PER3(4/4) genotype may accelerate the course of disease in MS susceptible individuals.

PMID: 29055480 [PubMed - in process]

Spontaneous yawning in patients with multiple sclerosis: A polygraphic study.

Mult Scler Relat Disord. 2017 Oct;17:179-183

Authors: Erkoyun HU, Beckmann Y, Bülbül NG, İncesu TK, Kanat NG, Ertekin C

Abstract
BACKGROUND: Patients with multiple sclerosis (MS) suffer from the repetitive yawning and sleep problems. Yawning is observed in MS and other central nervous system disorders and yawning and swallowing may be controlled by the network of the brain stem. Therefore it is important to investigate the MS patients with various clinical and radiological locations in order to understand the role of brainstem on the yawning mechanisms. One hour polygraphic recording would be crucial method for this purpose, because it is easy to observe spontaneous yawning (SY) and spontaneous swallowing (SS) together with their electrophysiologic counterparts. Previous studies reported that contagious yawn and swallow are temporally related and frequency of swallows was increased within 10s of post yawn period in normal adult subjects. We have re-investigated this phenomenon by studying the SY and SS in polygraphic recording in normal subjects and patients with MS. Then we hypothesized that SY is expected to be increased in MS patients.
METHODS: 49 patients with MS and 19 control subjects were recruited in this study. We used a twelve-channel electroencephalography (EEG) device. Five channels were for electromyography (EMG) recording. We also used one channel for laryngeal sensor for vertical movements of the larynx during swallowing. Cardiac rhythm, respiration and sympathetic skin responses were synchronously recorded during swallowing. We evaluated rate of total SY, swallows inside the yawning, before and after 10s of the yawning and yawning unrelated with swallowing.
RESULTS: Patients with MS yawned more frequently than healthy controls (p = 0,044). It was obvious that the yawning unrelated with spontaneous swallow was also significantly increased compared to normal controls (p = 0,047), whereas swallowing inside the yawn or before and after 10s of yawning were not significantly different in both groups. Among 49 MS patients, 16 (32.6%) had brainstem involvement. Yawning was observed in only 6 (37.5%) of them.
CONCLUSION: Yawning is significantly increased in MS patients compared to normal controls by using the polygraphic method. There is no direct relation of the brainstem and the origin of yawning in MS patients according to clinical picture and MRI findings. However safe swallows during yawning could suggest that there is still need to some brain stem mechanism and/or oropharyngeal reflexes. Difficulties must be emphasized to detect anatomic localization in MS because of relapsing pattern of disease.

PMID: 29055454 [PubMed - in process]

Sleep apnea: An overlooked cause of lipotoxicity?

Med Hypotheses. 2017 Oct;108:161-165

Authors: Gu C, Younas H, Jun JC

Abstract
Obstructive sleep apnea (OSA) is a common sleep disorder associated with diabetes and cardiovascular disease. However, the mechanisms by which OSA causes cardiometabolic dysfunction are not fully elucidated. OSA increases plasma free fatty acids (FFA) during sleep, reflecting excessive adipose tissue lipolysis. In animal studies, intermittent hypoxia simulating OSA also increases FFA, and the increase is attenuated by beta-adrenergic blockade. In other contexts, excessive plasma FFA can lead to ectopic fat accumulation, insulin resistance, vascular dysfunction, and dyslipidemia. Herein, we propose that OSA is a cause of excessive adipose tissue lipolysis contributing towards systemic "lipotoxicity". Since visceral and upper-body obesity contributes to OSA pathogenesis, OSA-induced lipolysis may further aggravate the consequences of this metabolically harmful state. If this hypothesis is correct, then OSA may represent a reversible risk factor for cardio-metabolic dysfunction, and this risk might be mitigated by preventing OSA-induced lipolysis during sleep.

PMID: 29055392 [PubMed - in process]