Intralingual and Intrapleural AAV Gene Therapy Prolongs Survival in a SOD1 ALS Mouse Model

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that results in death from respiratory failure. No cure exists for this devastating disease, but therapy that directly targets the respiratory system has the potential to prolong survival and improve quality of life in some cases of ALS. The objective of this study was to enhance breathing and prolong survival by suppressing superoxide dismutase 1 (SOD1) expression in respiratory motor neurons using adeno-associated virus (AAV) expressing an artificial microRNA targeting the SOD1 gene. AAV-miR(SOD1) was injected in the tongue and intrapleural space of SOD1(G93A) mice, and repetitive respiratory and behavioral measurements were performed until the end stage. Robust silencing of SOD1 was observed in the diaphragm and tongue as well as systemically. Silencing of SOD1 prolonged survival by approximately 50 days, and it delayed weight loss and limb weakness in treated animals compared to untreated controls. Histologically, there was preservation of the neuromuscular junctions in the diaphragm as well as the number of axons in the phrenic and hypoglossal nerves. Although SOD1 suppression improved breathing and prolonged survival, it did not ameliorate the restrictive lung phenotype. Suppression of SOD1 expression in motor neurons that underlie respiratory function prolongs survival and enhances breathing until the end stage in SOD1(G93A) ALS mice

Sex, stress and sleep apnoea: decreased susceptibility to upper airway muscle dysfunction following intermittent hypoxia in females

Obstructive sleep apnoea syndrome (OSAS) is a devastating respiratory control disorder more common in men than women. The reasons for the sex difference in prevalence are multifactorial, but are partly attributable to protective effects of oestrogen. Indeed, OSAS prevalence increases in post-menopausal women. OSAS is characterized by repeated occlusions of the pharyngeal airway during sleep. Dysfunction of the upper airway muscles controlling airway calibre and collapsibility is implicated in the pathophysiology of OSAS, and sex differences in the neuro-mechanical control of upper airway patency are described. It is widely recognized that chronic intermittent hypoxia (CIH), a cardinal feature of OSAS due to recurrent apnoea, drives many of the morbid consequences characteristic of the disorder. In rodents, exposure to CIH-related redox stress causes upper airway muscle weakness and fatigue, associated with mitochondrial dysfunction. Of interest, in adults, there is female resilience to CIH-induced muscle dysfunction. Conversely, exposure to CIH in early life, results in upper airway muscle weakness equivalent between the two sexes at 3 and 6 weeks of age. Ovariectomy exacerbates the deleterious effects of exposure to CIH in adult female upper airway muscle, an effect partially restored by oestrogen replacement therapy. Intriguingly, female advantage intrinsic to upper airway muscle exists with evidence of substantially greater loss of performance in male muscle during acute exposure to severe hypoxic stress. Sex differences in upper airway muscle physiology may have relevance to human OSAS. The oestrogen–oestrogen receptor α axis represents a potential therapeutic target in OSAS, particularly in post-menopausal women

Intensity of respiratory cortical arousals is a distinct pathophysiologic feature and is associated with disease severity in obstructive sleep apnea patients

Background: We investigated whether the number, duration and intensity of respiratory arousals (RA) on C3-electroencephalographic (EEG) recordings correlate with polysomnography (PSG)-related disease severity in obstructive sleep apnea (OSA) patients. We also investigated if every patient might have an individual RA microstructure pattern, independent from OSA-severity. Methods: PSG recordings of 20 OSA patients (9 female; age 27–80 years) were analyzed retrospectively. Correlation coefficients were calculated between RA microstructure (duration, EEG-intensity) and RA number and respiratory disturbance index (RDI), oxygen desaturation index (ODI) and arousal index (AI). Intraclass correlations (ICC) for both RA duration and intensity were calculated. Sleep stage-specific and apnea- and hypopnea-specific analyses were also done. The probability distributions of duration and intensity were plotted, interpolated with a kernel which fits the distribution. A Bayesian posterior distribution analysis and pair-wise comparisons of each patient with all other 19 patients were performed. Results: Of the analyzed 2600 RA, strong positive correlations were found between average RA intensity and both RDI and AI. The number of PSG-recorded RA was strongly positively correlated with RDI. Significant correlations between average RA intensity in REM, NREM2 and NREM3 sleep stages and total ODI were identified. No sleep stage-specific correlations of arousal microstructure with age, sex, RDI or AI were identified. Although between-subjects ICC values were 0.7 (all p < 0.05). While apnea-related RA duration did not differ from hypopnea-related RA duration, RA intensity was significantly higher (p = 0.00135) in hypopneas than in apneas. A clear individual pattern of arousal duration for each patient was made distinct. For arousal intensity, a Gaussian distribution was identified in most patients. The Bayesian statistics regarding the arousal microstructure showed significant differences between each pair of patients. Conclusions: Each individual patient with OSA might have an individual pattern of RA intensity and duration indicating a distinct individual pathophysiological feature. Arousal intensity was significantly higher in hypopneic than in apneic events and may be related causally to the diminished (compared to apneas) respiratory distress associated with hypopneas. RA intensity in REM, NREM2 and NREM3 strongly correlated with ODI

Loss of FHL1 induces an age-dependent skeletal muscle myopathy associated with myofibrillar and intermyofibrillar disorganization in mice

Recent human genetic studies have provided evidences that sporadic or inherited missense mutations in four-and-a-half LIM domain protein 1 (FHL1), resulting in alterations in FHL1 protein expression, are associated with rare congenital myopathies, including reducing body myopathy and Emery–Dreifuss muscular dystrophy. However, it remains to be clarified whether mutations in FHL1 cause skeletal muscle remodeling owing to gain- or loss of FHL1 function. In this study, we used FHL1-null mice lacking global FHL1 expression to evaluate loss-of-function effects on skeletal muscle homeostasis. Histological and functional analyses of soleus, tibialis anterior and sternohyoideus muscles demonstrated that FHL1-null mice develop an age-dependent myopathy associated with myofibrillar and intermyofibrillar (mitochondrial and sarcoplasmic reticulum) disorganization, impaired muscle oxidative capacity and increased autophagic activity. A longitudinal study established decreased survival rates in FHL1-null mice, associated with age-dependent impairment of muscle contractile function and a significantly lower exercise capacity. Analysis of primary myoblasts isolated from FHL1-null muscles demonstrated early muscle fiber differentiation and maturation defects, which could be rescued by re-expression of the FHL1A isoform, highlighting that FHL1A is necessary for proper muscle fiber differentiation and maturation in vitro. Overall, our data show that loss of FHL1 function leads to myopathy in vivo and suggest that loss of function of FHL1 may be one of the mechanisms underlying muscle dystrophy in patients with FHL1 mutations

The relationship between partial upper-airway obstruction and inter-breath transition period during sleep

Short pauses or “transition-periods” at the end of expiration and prior to subsequent inspiration are commonly observed during sleep in humans. However, the role of transition periods in regulating ventilation during physiological challenges such as partial airway obstruction (PAO) has not been investigated. Twenty-nine obstructive sleep apnea patients and eight controls underwent overnight polysomnography with an epiglottic catheter. Sustained-PAO segments (increased epiglottic pressure over ≥5 breaths without increased peak inspiratory flow) and unobstructed reference segments were manually scored during apnea-free non-REM sleep. Nasal pressure data was computationally segmented into inspiratory (T, shortest period achieving 95% inspiratory volume), expiratory (T, shortest period achieving 95% expiratory volume), and inter-breath transition period (T, period between T and subsequent T). Compared with reference segments, sustained-PAO segments had a mean relative reduction in T (−24.7\ua0±\ua017.6%, P\ua

The Relationship between Alcohol Drinking Patterns and Sleep Duration among Black and White Men and Women in the United States

In the United States, racial minorities generally experience poorer cardiovascular health compared to whites, and differences in alcohol consumption and sleep could contribute to these disparities. With a nationally representative sample of 187,950 adults in the National Health Interview Survey from 2004 to 2015, we examined the relationship between alcohol-drinking patterns and sleep duration/quality by race and sex. Using Poisson regression models with robust variance, we estimated sex-specific prevalence ratios for each sleep duration/quality category among blacks compared to whites within categories of alcohol-drinking pattern, adjusting for socioeconomic status and other potential confounders. Across alcohol drinking patterns, blacks were less likely than whites to report recommended sleep of 7–<9 h/day. Short (PR = 1.30 [95% CI: 1.22–1.39]) and long (PR = 1.30 [95% CI: 1.07–1.58]) sleep were 30% more prevalent among black-male infrequent heavy drinkers compared to white-male infrequent heavy drinkers. Short (PR = 1.27 [95% CI: 1.21–1.34]) sleep was more prevalent among black-female infrequent heavy drinkers compared to white-female infrequent heavy drinkers, but there was no difference for long sleep (PR = 1.09 [95% CI: 0.97–1.23]). Black female infrequent moderate drinkers, however, had a 16% higher (PR = 1.16 [95% CI: 1.01–1.33]) prevalence of long sleep compared to their white counterparts. Environmental, social, and biological factors contributing to these findings, along with their impact on disparate health outcomes, should be studied in greater detail

Dilation of the oropharynx via selective stimulation of the hypoglossal nerve

Obstructive sleep apnea (OSA) is caused by the retraction of the tongue to occlude the upper airway (UAW). Electrical stimulation of the tongue protrudor and retractor muscle has been demonstrated as an effective technique to alleviate UAW obstructions and is considered to be a potential treatment for OSA. Recent studies have shown that selective stimulation of the hypoglossal nerve (HG) to activate tongue muscles using a single implantable device presents an attractive approach for treating OSA. In this study, the functional outcome of selective hypoglossal nerve stimulation with a multi-contact peripheral nerve electrode was studied by imaging the airway in anesthetized beagles. A pulse train of varying amplitude was applied through each one of the tripolar contact sets of the nerve electrode while the pharyngeal images were acquired via a video grabber into a computer. For the open mouth positions, the tongue activation patterns were also viewed and videotaped with a digital camcorder through the mouth. The percent dilation of the pharyngeal opening for each contact was calculated. The images show that stimulations delivered through the electrode contacts placed around the HG nerve trunk can generate several different activation patterns of the tongue muscles. Some of these patterns translate into a substantial increase in the oropharyngeal size, while others do not have any effect on the pharynx. The activation patterns vary as a function of the head position and the lower jaw. These results suggest that selective nerve stimulation can be a useful technique to maximize the effects of HG nerve stimulation in removing the obstructions in sleep apnea patients

Endocannabinoids and excitotoxicity: lessons from hypoglossal motoneurons

Brainstem hypoglossal motoneurons (HMs) exclusively innervate tongue muscles and are severely damaged in the neurodegenerative disease called amyotrophic lateral sclerosis (ALS). One mechanism leading to such cell death is proposed to be glutamate-mediated excitotoxic stress. HMs are particularly vulnerable to excitotoxicity due to their expression of calcium-permeable \u3b1-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors and scarcity of intracellular Ca2+ binding proteins like parvalbumin and calbindin. Indeed, blocking glutamate uptake in medullary slices can lead to pathological bursting and motoneuron damage. The endocannabinoid system is widely distributed in the brain and is believed to be an important regulator of synaptic transmission. Several studies reported neuroprotection mediated by the endocannabinoid system in such pathological insults like brain ischemia, traumatic brain injury or excitotoxicity. Moreover, in ALS animal models, up-regulation of the endocannabinoid system has been detected, suggesting it can play a role during disease development. Thus, detailed information on how the endocannabinoid system can affect cells during pathological insults like excitotoxicity is a valuable asset for future investigations of novel therapy approaches for ALS. The objective of this work was to investigate the effect of modulation of the endocannabinoid system during excitotoxic stress in hypoglossal motoneurons in vitro. Thin medullary slices (for electrophysiology and viability assay) or whole brainstem isolates (for Western Blot) from postnatal Wistar rats were used. Each slice/brainstem containing hypoglossal nuclei was transferred to a recording/incubation chamber and superfused with oxygenated Krebs solution. Excitotoxic stress was evoked by application of DL-TBOA (DL-threo-\u3b2-benzyloxyaspartic acid, 50 \u3bcM), a potent and selective inhibitor of excitatory amino acid transporters, with consequent build-up of extracellular glutamate. It was observed that modulation of endocannabinoid CB1 receptor (CB1R) function affected TBOA-evoked bursting, an event previously correlated with TBOA toxicity. Co-application of the endocannabinoid anandamide (AEA, 10 \u3bcM), a CB1R agonist, with TBOA resulted in lowered probability of the occurrence of pathological bursting, whereas co-application of the CB1R antagonist AM251 (10 \u3bcM) disrupted TBOA-induced bursts, leading to their \u201cfragmentation\u201d. Furthermore, AEA significantly decreased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) isolated by co-application of bicuculline and strychnine (10 \u3bcM and 0.4 \u3bcM, respectively) and caused occurrence of biphasic activity in spontaneous inhibitory postsynaptic currents (sIPSCs; isolated by co-application of DNQX and APV at 10 \u3bcM and 50 \u3bcM, respectively) in some of the recorded cells. AM251 caused a decrease in the frequency of sIPSCs, but during application of bicuculline and strychnine it evoked activity which partly resembled bursting observed during TBOA application. Moreover, co-application of AEA with TBOA significantly decreased the number of damaged propidium iodide-positive cells with respect to counterstained Hoechst 33342-positive cells, which suggests a protective effect of this CB1R agonist against TBOA-induced toxicity. In addition, Western blot analysis showed a significant increase in CB1R protein levels after only 4 hours of TBOA incubation, indicating that the endocannabinoid system is activated during this excitotoxic insult. We suggest that a likely role of the endocannabinoid system in our brainstem preparation is to counteract the effects and consequences of elevated glutamate levels in the extracellular compartment

Electronic devices and systems for monitoring of diabetes and cardiovascular diseases

Diabetes is a serious chronic disease which causes a high rate of morbidity and mortality all over the world. In 2007, more than 246 million people suffered from diabetes worldwide and unfortunately the incidence of diabetes is increasing at alarming rates. The number of people with diabetes is expected to double within the next 25 years due to a combination of population ageing, unhealthy diets, obesity and sedentary lifestyles. It can lead to blindness, heart disease, stroke, kidney failure, amputations and nerve damage. In women, diabetes can cause problems during pregnancy and make it more likely for the baby to be born with birth defects. Moreover, statistical analysis shows that 75% of diabetic patients die prematurely of cardiovascular disease (CVD). The absolute risk of cardiovascular disease in patients with type 1 (insulin-dependent) diabetes is lower than that in patients with type 2 (non-insulin-dependent) diabetes, in part because of their younger age and the lower prevalence of CVD risk factors, and in part because of the different pathophysiology of the two diseases. Unfortunately, about 9 out of 10 people with diabetes have type 2 diabetes. For these reasons, cardiopathes and diabetic patients need to be frequently monitored and in some cases they could easily perform at home the requested physiological measurements (i.e. glycemia, heart rate, blood pressure, body weight, and so on) sending the measured data to the care staff in the hospital. Several researches have been presented over the last years to address these issues by means of digital communication systems. The largest part of such works uses a PC or complex hardware/software systems for this purpose. Beyond the cost of such systems, it should be noted that they can be quite accessible by relatively young people but the same does not hold for elderly patients more accustomed to traditional equipments for personal entertainment such as TV sets. Wearable devices can permit continuous cardiovascular monitoring both in clinical settings and at home. Benefits may be realized in the diagnosis and treatment of a number of major 15 diseases. In conjunction with appropriate alarm algorithms, they can increase surveillance capabilities for CVD catastrophe for high-risk subjects. Moreover, they could play an important role in the wireless surveillance of people during hazardous operations (military, fire-fighting, etc.) or during sport activities. For patients with chronic cardiovascular disease, such as heart failure, home monitoring employing wearable device and tele-home care systems may detect exacerbations in very early stages or at dangerous levels that necessitate an emergency room visit and an immediate hospital admission. Taking into account mains principles for the design of good wearable devices and friendly tele-home care systems, such as safety, compactness, motion and other disturbance rejection, data storage and transmission, low power consumption, no direct doctor supervision, it is imperative that these systems are easy to use and comfortable to wear for long periods of time. The aim of this work is to develop an easy to use tele-home care system for diabetes and cardiovascular monitoring, well exploitable even by elderly people, which are the main target of a telemedicine system, and wearable devices for long term measuring of some parameters related to sleep apnoea, heart attack, atrial fibrillation and deep vein thrombosis. Since set-top boxes for Digital Video Broadcast Terrestrial (DVB-T) are in simple computers with their Operating System, a Java Virtual Machine, a modem for the uplink connection and a set of standard ports for the interfacing with external devices, elderly, diabetics and cardiopathes could easily send their self-made exam to the care staff placed elsewhere. The wearable devices developed are based on the well known photopletysmographic method which uses a led source/detector pair applied on the skin in order to obtain a biomedical signal related to the volume and percentage of oxygen in blood. Such devices investigate the possibility to obtain more information to those usually obtained by this technique (heart rate and percentage of oxygen saturation) in order to discover new algorithms for the continuous and remote or in ambulatory monitoring and screening of sleep apnoea, heart attack, atrial fibrillation and deep vein thrombosis