Common Sleep Disorders in Adults: Diagnosis and Management

Sleep disorders are common in the general adult population and are associated with adverse effects such as motor vehicle collisions, decreased quality of life, and increased mortality. Patients with sleep disorders can be categorized into three groups: people with problems falling asleep, people with behavior and movement disturbances during sleep, and people with excessive daytime sleepiness. Insomnia, the most common sleep disorder, is defined by difficulty initiating sleep, maintaining sleep, or both, resulting in daytime consequences. Insomnia is diagnosed by history and is treated with cognitive behavior therapy, with or without medications. Rapid eye movement sleep behavior disorder is characterized by increased muscle tone during rapid eye movement sleep, resulting in patients acting out their dreams with potentially harmful effects. Rapid eye movement sleep behavior disorder is diagnosed by polysomnography and treated with melatonin or clonazepam. Restless legs syndrome is defined by an urge to move the legs that worsens when at rest. Restless legs syndrome is treated with gabapentin or dopamine agonists, depending on the severity. Narcolepsy is characterized by excessive daytime sleepiness, cataplexy, sleep paralysis, and sleep hallucinations. Diagnosis is suggested by the history and can be confirmed with polysomnography and a multiple sleep latency test the following day. Narcolepsy is treated with behavior modifications and medications such as stimulants, selective serotonin reuptake inhibitors, sodium oxybate, and pitolisant. Obstructive sleep apnea may be diagnosed in patients with excessive snoring and witnessed apneas and can be diagnosed using overnight polysomnography. Treatment consists of positive airway pressure therapy while sleeping in conjunction with weight loss.

Combined administration of testosterone plus an ornithine decarboxylase inhibitor as a selective prostate-sparing anabolic therapy

Because of its anabolic effects on muscle, testosterone is being explored as a function-promoting anabolic therapy for functional limitations associated with aging; however, concerns about testosterone's adverse effects on prostate have inspired efforts to develop strategies that selectively increase muscle mass while sparing the prostate. Testosterone's promyogenic effects are mediated through upregulation of follistatin. We show here that the administration of recombinant follistatin (rFst) increased muscle mass in mice, but had no effect on prostate mass. Consistent with the results of rFst administration, follistatin transgenic mice with constitutively elevated follistatin levels displayed greater muscle mass than controls, but had similar prostate weights. To elucidate signaling pathways regulated differentially by testosterone and rFst in prostate and muscle, we performed microarray analysis of mRNAs from prostate and levator ani of castrated male mice treated with vehicle, testosterone, or rFst. Testosterone and rFst shared the regulation of many transcripts in levator ani; however, in prostate, 593 transcripts in several growth-promoting pathways were differentially expressed after testosterone treatment, while rFst showed a negligible effect with only 9 transcripts differentially expressed. Among pathways that were differentially responsive to testosterone in prostate, we identified ornithine decarboxylase (Odc1), an enzyme in polyamine biosynthesis, as a testosterone-responsive gene that is unresponsive to rFst. Accordingly, we administered testosterone with and without α-difluoromethylornithine (DFMO), an Odc1 inhibitor, to castrated mice. DFMO selectively blocked testosterone's effects on prostate, but did not affect testosterone's anabolic effects on muscle. Co-administration of testosterone and Odc1 inhibitor presents a novel therapeutic strategy for prostate-sparing anabolic therapy.

Guanidinium chloride-induced spectral perturbations of 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid confound interpretation of data on molten globule states

We describe limitations in the use of 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid (bis-ANS) to examine unfolding intermediates associated with guanidinium chloride (GuHCl)-induced protein denaturation. Several studies have used alterations in fluorescence emission of bis-ANS to quantify the population of "molten globule" states. Our findings indicate that the observed changes in bis-ANS spectroscopic properties could originate from the interactions of bis-ANS and GuHCl and the aggregation of the dye at higher GuHCl concentrations. We posit that in the absence of additional complementary structural or spectroscopic measurements, the use of bis-ANS emission alone to monitor protein conformations can be misleading.

Effects of dihydrotestosterone on differentiation and proliferation of human mesenchymal stem cells and preadipocytes

The mechanisms by which androgens regulate fat mass are poorly understood. Although testosterone has been reported to increase lipolysis and inhibit lipid uptake, androgen effects on proliferation and differentiation of human mesenchymal stem cells (hMSCs) and preadipocytes have not been studied. Here, we investigated whether dihydrotestosterone (DHT) regulates proliferation, differentiation, or functional maturation of hMSCs and human preadipocytes from different fat depots. DHT (0-30 nM) dose-dependently inhibited lipid accumulation in adipocytes differentiated from hMSCs and downregulated expression of aP2, PPARgamma, leptin, and C/EBPalpha. Bicalutamide attenuated DHT's inhibitory effects on adipogenic differentiation of hMSCs. Adipocytes differentiated in presence of DHT accumulated smaller oil droplets suggesting reduced extent of maturation. DHT decreased the incorporation of labeled fatty acid into triglyceride, and downregulated acetyl CoA carboxylase and DGAT2 expression in adipocytes derived from hMSCs. DHT also inhibited lipid accumulation and downregulated aP2 and C/EBPalpha in human subcutaneous, mesenteric and omental preadipocytes. DHT stimulated forskolin-stimulated lipolysis in subcutaneous and mesenteric preadipocytes and inhibited incorporation of fatty acid into triglyceride in adipocytes differentiated from preadipocytes from all fat depots.

CONCLUSIONS

DHT inhibits adipogenic differentiation of hMSCs and human preadipocytes through an AR-mediated pathway, but it does not affect the proliferation of either hMSCs or preadipocytes. Androgen effects on fat mass represent the combined effect of decreased differentiation of fat cell precursors, increased lipolysis, and reduced lipid accumulation.