Reduced Serum Levels of Soluble Interleukin-15 Receptor α in Schizophrenia and Its Relationship to the Excited Phenotype.

Our previous studies documented that interleukin-15 receptor α (IL-15Rα) knockout (KO) mice exhibited hyperactivity, memory impairment, and desperate behavior, which are core features of schizophrenia and depression. Due to the overlapping symptomology and pathogenesis observed for schizophrenia and depression, the present study attempted to determine whether IL-15Rα was associated with the risk of schizophrenia or depression. One hundred fifty-six participants, including 63 schizophrenia patients, 29 depressive patients, and 64 age-matched healthy controls, were enrolled in the study. We investigated the circulating levels of soluble IL-15Rα and analyzed potential links between the IL-15Rα levels and clinical symptoms present in schizophrenia or depressive patients. We observed reduced serum IL-15Rα levels in schizophrenia patients, but not depressive patients compared with controls. Moreover, a significant negative association was observed between the circulating IL-15Rα levels and excited phenotypes in the schizophrenia patients. The IL-15Rα KO mice displayed pronounced pre-pulse inhibition impairment, which was a typical symptom of schizophrenia. Interestingly, the IL-15Rα KO mice exhibited a remarkable elevation in the startle amplitude in the startle reflex test compared to wild type mice. These results demonstrated that serum levels of soluble IL-15Rα were reduced in schizophrenia and highlighted the relationship of IL-15Rα and the excited phenotype in schizophrenia patients and mice.

Management of abdominal compartment syndrome in acute pancreatitis.

Abdominal compartment syndrome (ACS), defined by the presence of increased intra-abdominal pressure>20mmHg in association with failure of at least one organ system, is a common and feared complication that may occur in the early phase of severe acute pancreatitis (AP). This complication can lead to patient death in the very short term. The goal of this review is to provide the surgeon and intensivist with objective information to help them in their decision-making. In the early phase of severe AP, it is essential to monitor intra-vesical pressure (iVP) to allow early diagnosis of intra-abdominal hypertension or ACS. The treatment of ACS is both medical and surgical requiring close collaboration between the surgical and resuscitation teams. Medical treatment includes vascular volume repletion, prokinetic agents, effective curarization and percutaneous drainage of large-volume ascites. If uncontrolled respiratory or cardiac failure develops or if maximum medical treatment fails, most teams favor performing an emergency xipho-pubic decompression laparotomy with laparostomy. This procedure follows the principles of abbreviated laparotomy as described for abdominal trauma.

Goni Moreno progressive preoperative pneumoperitoneum for giant hernias: a monocentric retrospective study of 162 patients.

INTRODUCTION: Goni Moreno's procedure was described 60 years ago as a solution for giant hernias repair through the creation of a progressive preoperative pneumoperitoneum (PPP). The main objective of the present study is to assess its effectiveness in terms of primary fascial closures. The secondary objectives of this study are to explore the morbidity and mortality associated with Moreno's procedure using 40 years of data from a large cohort of patients. MATERIALS AND METHODS: This is a retrospective study of all patients who underwent PPP procedures between October 1974 and January 2019 at the digestive surgery unit at Grenoble University Hospital, France. Data were reviewed to assess the preoperative demographic characteristics of the patients, procedure, postoperative course, complication following Clavien-Dindo classification and 30-day outcomes. RESULTS: 162 procedures were attempted. The mean age of patients was 57.8 years. 83 patients had a history of chronic respiratory disease (51.2%). The mean BMI was 33.2 kg/m2, and 52 patients were obese (32.1%) Half of the patients were classified as ASA score III. Success rate of fascial closures was 95.7%. The global rate of complication during the insufflation period and after surgical repair of the hernia was 51.8% (n = 84). Among these, only 16.7% (n = 27) were major according to the Clavien-Dindo classification. The global mortality rate was 3.1%. CONCLUSION: Goni Moreno PPP is an effective procedure that allows a high rate of fascial closure. The population of patients requiring such procedures presents a high-risk profile for complications regarding demographics and associated diseases.

Phenotypic Resemblance to Neuropsychiatric Disorder and Altered mRNA Profiles in Cortex and Hippocampus Underlying IL15Rα Knockout.

BACKGROUND: Previous studies of the functions of IL15Rα have been limited to immune activities and skeletal muscle development. Immunological factors have been identified as one of the multiple causes of psychosis, and neurological symptoms have been described in IL15Rα knockout (KO) mice. Seeking to explore possible mechanisms for this in the IL15Rα-/- mouse brain, we analyzed gene expression patterns in the cortex and hippocampus using the RNA-seq technique. METHODS: IL15Rα KO mice were generated and littermate wildtype (WT) mice were used as a control group. A Y-maze was used to assess behavior differences between the two groups. The cortex and hippocampus of 3-month-old male mice were prepared and RNA-seq and transcriptome analysis were performed by gene set enrichment analysis (GSEA). RESULTS: Compared with the WT group, IL15Rα KO animals showed higher speed in the novel arm and more entrance frequency in the old arm in the Y-maze experiment. GSEA indicated that 18 pathways were downregulated and 13 pathways upregulated in both cortex and hippocampus from the GO, KEGG, and Hallmark gene sets. The downregulated pathways formed three clusters: respiratory chain and electron transport, regulation of steroid process, and skeletal muscle development. CONCLUSION: IL15Rα KO mice exhibit altered expression of multiple pathways, which could affect many functions of the brain. Lipid biosynthesis and metabolism in the central nervous system (CNS) should be investigated to provide insights into the effect of IL15Rα on psychosis in this murine model.

Schizophrenia Patient Shows a Rare Interleukin 15 Receptor alpha Variant Disrupting Signal Transduction.

BACKGROUND: Schizophrenia is a complex and debilitating mental disorder with strong heritability. Its pathogenesis involves immune dysregulation. Interleukin 15 and interleukin 15 receptor alpha(IL-15Rα) are classical immune molecules. They also help maintain normal brain function, leading to our hypothesis that IL-15Rα gene(IL- 15RA) variants contribute to the pathogenesis of schizophrenia. OBJECTIVE: We determine whether the genetic variants of IL-15RA are associated with the development and progression of schizophrenia and whether IL-15RA single nucleotide polymorphism(SNP) plays a key role in downstream signaling transduction. METHODS AND RESULTS: We sequenced IL-15RA exon from 132 Chinese schizophrenic patients and identified a rare variant(rs528238821) in a patient diagnosed with catatonic schizophrenia and ankylosing spondylitis(AS). We overexpressed this missense variant in cells driven by pBI-CMV vector. The cells showed attenuated STAT3 phosphorylation in response to interleukin15. CONCLUSION: IL-15RA mutation is rare in schizophrenic patients but interfered with IL- 15Rα intracellular signal transduction. Given the similarity of symptoms of catatonic schizophrenia and the known phenotype of IL-15Rα knockout mice, gene variation might offer diagnostic value for sub-types of schizophrenia.

The Amazon rain forest plant Uncaria tomentosa (cat's claw) and its specific proanthocyanidin constituents are potent inhibitors and reducers of both brain plaques and tangles.

Brain aging and Alzheimer's disease both demonstrate the accumulation of beta-amyloid protein containing "plaques" and tau protein containing "tangles" that contribute to accelerated memory loss and cognitive decline. In the present investigation we identified a specific plant extract and its constituents as a potential alternative natural solution for preventing and reducing both brain "plaques and tangles". PTI-00703 cat's claw (Uncaria tomentosa from a specific Peruvian source), a specific and natural plant extract from the Amazon rain forest, was identified as a potent inhibitor and reducer of both beta-amyloid fibrils (the main component of "plaques") and tau protein paired helical filaments/fibrils (the main component of "tangles"). PTI-00703 cat's claw demonstrated both the ability to prevent formation/aggregation and disaggregate preformed Aß fibrils (1-42 and 1-40) and tau protein tangles/filaments. The disaggregation/dissolution of Aß fibrils occurred nearly instantly when PTI-00703 cat's claw and Aß fibrils were mixed together as shown by a variety of methods including Thioflavin T fluorometry, Congo red staining, Thioflavin S fluorescence and electron microscopy. Sophisticated structural elucidation studies identified the major fractions and specific constituents within PTI-00703 cat's claw responsible for both the observed "plaque" and "tangle" inhibitory and reducing activity. Specific proanthocyanidins (i.e. epicatechin dimers and variants thereof) are newly identified polyphenolic components within Uncaria tomentosa that possess both "plaque and tangle" reducing and inhibitory activity. One major identified specific polyphenol within PTI-00703 cat's claw was epicatechin-4ß-8-epicatechin (i.e. an epicatechin dimer known as proanthocyanidin B2) that markedly reduced brain plaque load and improved short-term memory in younger and older APP "plaque-producing" (TASD-41) transgenic mice (bearing London and Swedish mutations). Proanthocyanidin B2 was also a potent inhibitor of brain inflammation as shown by reduction in astrocytosis and gliosis in TASD-41 transgenic mice. Blood-brain-barrier studies in Sprague-Dawley rats and CD-1 mice indicated that the major components of PTI-00703 cat's claw crossed the blood-brain-barrier and entered the brain parenchyma within 2 minutes of being in the blood. The discovery of a natural plant extract from the Amazon rain forest plant (i.e. Uncaria tomentosa or cat's claw) as both a potent "plaque and tangle" inhibitor and disaggregator is postulated to represent a potential breakthrough for the natural treatment of both normal brain aging and Alzheimer's disease.

Relevance of early CT scan diagnosis of blunt diaphragmatic injury: A retrospective analysis from the Northern French Alps Emergency Network.

INTRODUCTION: Diaphragmatic rupture following blunt trauma occurs rarely. Classically described after high-velocity accidents, ruptures are often associated with multiple organ injuries. The diagnosis is sometimes difficult. The goal of this study was to analyze and to discuss the modalities of early radiologic diagnosis and management of these injuries. PATIENTS AND METHODS: This multicenter retrospective study included patients seen between 2009 and 2017 within the Northern Alpine Emergency Network [REseau Nord Alpin des Urgences (RENAU)]. Clinical, radiologic and surgical data from all patients sustaining blunt diaphragmatic rupture were studied. RESULTS: Thirty-one patients (18 men and 13 women), median age 44, were included. The principle mechanism of injury was road or traffic accidents for 22 patients. Diaphragmatic rupture occurred on the left side in 23 patients. Diagnosis was delayed in two patients, at 11 days and three months after the initial accident. Chest X-rays were diagnostic in 18 of 29 patients. CT scan was the reference investigation since it was performed in all patients and confirmed the diagnosis in 26 instances. Repair was surgical via a midline laparotomy in 27 patients, via laparoscopy in three, and via thoracoscopy in one. Three patients died. CONCLUSION: At urgent surgical exploration in the unstable blunt trauma patient, the surgeon should keep in mind the relatively poor diagnostic performance of chest X-rays. Accurate diagnosis relies on routine inspection of the diaphragmatic cupolas. In the stable trauma victim, contrast-enhanced abdomino-thoracic CT with reconstruction can lead to early diagnosis, which allows for repair under optimal conditions, whether by laparotomy, laparoscopy or thoracoscopy, according to local conditions and expertise.

Retrospective study of thoracotomy performed in a French level 1-trauma center.

OBJECTIVE: Resuscitative thoracotomy, a potentially life-saving procedure, is used exceptionally, and essentially for penetrating trauma. Most of the available literature is American while reports from Europe are sparse. We report our experience in a French level 1-trauma center. MATERIAL AND METHODS: Patient records (patient age, gender, mechanism of injury, indication for emergency thoracotomy, anatomic injuries, interventions and survival) for all patients who underwent emergency thoracotomy between January 2005 and December 2015 were analyzed. RESULTS: Twenty-two patients (19 males) underwent emergency thoracotomy. Median age was 27.5 (12-67) years. Twelve were performed for blunt trauma (55%) and 10 for penetrating injuries (45%). Thirteen patients presented with cardiac arrest, while nine had deep and refractory hypotension. Overall, survival was 32% (n=7). There were no survivors in the blunt trauma group while seven of ten with penetrating injuries survived. All patients presenting with cardiac arrest died. CONCLUSION: The survival rate in this French retrospective study was in accordance with the literature.

The Blood-Brain Barrier: Regulatory Roles in Wakefulness and Sleep.

Sleep and its disorders are known to affect the functions of essential organs and systems in the body. However, very little is known about how the blood-brain barrier (BBB) is regulated. A few years ago, we launched a project to determine the impact of sleep fragmentation and chronic sleep restriction on BBB functions, including permeability to fluorescent tracers, tight junction protein expression and distribution, glucose and other solute transporter activities, and mediation of cellular mechanisms. Recent publications and relevant literature allow us to summarize here the sleep-BBB interactions in five sections: (1) the structural basis enabling the BBB to serve as a huge regulatory interface; (2) BBB transport and permeation of substances participating in sleep-wake regulation; (3) the circadian rhythm of BBB function; (4) the effect of experimental sleep disruption maneuvers on BBB activities, including regional heterogeneity, possible threshold effect, and reversibility; and (5) implications of sleep disruption-induced BBB dysfunction in neurodegeneration and CNS autoimmune diseases. After reading the review, the general audience should be convinced that the BBB is an important mediating interface for sleep-wake regulation and a crucial relay station of mind-body crosstalk. The pharmaceutical industry should take into consideration that sleep disruption alters the pharmacokinetics of BBB permeation and CNS drug delivery, being attentive to the chrono timing and activation of co-transporters in subjects with sleep disorders.

Involvement of the Blood-Brain Barrier in Metabolic Regulation.

Pertinent to pandemic obesity, the discovery of endogenous peptides that affect the ingestion of food has led to the question of how these ingestive peptides exert their actions in the brain. Whereas peripheral sources provide a ready reserve, the availability of ingestive peptides to their central nervous system targets can be regulated by the blood-brain barrier (BBB). Some of the peptides/polypeptides are transported by saturable mechanisms from blood to brain. Examples include leptin, insulin, mahogany, and pancreatic polypeptide. Some enter the brain by passive diffusion, such as neuropeptide Y, orexin A, cocaine- and amphetamine-regulated transcript, cyclo His-Pro, and amylin. Some others may have essentially no penetration of the BBB; this class includes agouti-related protein, melanin-concentrating hormone, and urocortin. The regulatory function of the BBB can be seen in various physiological states. Hyperglycemia may upregulate transport systems for leptin, urocortin, and galanin-like peptide, whereas fasting can down-regulate those for leptin and galanin-like peptide. Thus, the BBB plays a dynamic role in modulating the passage of ingestive peptides from blood to brain.

Spinal Cord Injury Changes Cytokine Transport.

Here we summarize three aspects of our understanding of the interactions of cytokines and neurotrophic peptides/proteins with the blood-brain and bloodspinal cord barriers (BBB): (a) pharmacokinetic analysis that has been reported for native cytokines and neurotrophic peptides/proteins; (b) landmark work on conjugated proteins to enhance their delivery across the normal BBB; and (c) regulatory changes under pathophysiological conditions in rodents, particularly after spinal cord injury (SCI). First, though the BBB restricts the permeation of large proteins, some cytokines and neurotrophic peptides/proteins in the periphery can reach the central nervous system (CNS) by specific transport systems. Moreover, SCI and some other disease processes may regulate these transport systems. The significance of studies of the transport systems is obvious because of the biological impact of these molecules on the CNS in health and disease. We have characterized the pharmacokinetic characteristics of some stable cytokines and neurotrophic peptides/proteins in mice after intravenous administration and also in the setting of in situ brain perfusion. In the particular case of SCI, there are time- and regionspecific changes of BBB permeability and transport systems. Tumor necrosis factor-α, a cytokine with dual actions in regeneration of the spinal cord, has a slow basal influx into the brain and spinal cord. After SCI, the increase in the entry of tumor necrosis factor-α to the CNS differs from leakage after BBB disruption and is related to upregulation of the transport system in a unique temporal and regional pattern. Overall, the permeation of cytokines across the BBB can be mediated by specific transport systems. The regulation of transport in pathophysiological conditions affects the extent of neuroinflammation and is implicated in neuroregeneration.

Management of blunt hepatic trauma.

For the last 20 years, nonoperative management (NOM) of blunt hepatic trauma (BHT) has been the initial policy whenever this is possible (80% of cases), i.e., in all cases where the hemodynamic status does not demand emergency laparotomy. NOM relies upon the coexistence of three highly effective treatment modalities: radiology with contrast-enhanced computerized tomography (CT) and hepatic arterial embolization, intensive care surveillance, and finally delayed surgery (DS). DS is not a failure of NOM management but rather an integral part of the surgical strategy. When imposed by hemodynamic instability, the immediate surgical option has seen its effectiveness transformed by development of the concept of abbreviated (damage control) laparotomy and wide application of the method of perihepatic packing (PHP). The effectiveness of these two conservative and cautious strategies for initial management is evidenced by current experience, but the management of secondary events that may arise with the most severe grades of injury must be both rapid and effective.

Management of splenic and pancreatic trauma.

The spleen and pancreas are at risk for injury during abdominal trauma. The spleen is more commonly injured because of its fragile structure and its position immediately beneath the ribs. Injury to the more deeply placed pancreas is classically characterized by discordance between the severity of pancreatic injury and its initial clinical expression. For the patient who presents with hemorrhagic shock and ultrasound evidence of major hemoperitoneum, urgent "damage control" laparotomy is essential; if splenic injury is the cause, prompt "hemostatic" splenectomy should be performed. Direct pancreatic injury is rarely the cause of major hemorrhage unless a major neighboring vessel is injured, but if there is destruction of the pancreatic head, a two-stage pancreatoduodenectomy (PD) may be indicated. At open laparotomy when the patient's hemodynamic status can be stabilized, it may be possible to control splenic bleeding without splenectomy; it is always essential to search for injury to the pancreatic duct and/or the adjacent duodenum. Pancreatic contusion without ductal rupture is usually treated by drain placement adjacent to the injury; ductal injuries of the pancreatic body or tail are treated by resection (distal pancreatectomy with or without splenectomy), with generally benign consequences. For injuries of the pancreatic head with pancreatic duct disruption, wide drainage is usually performed because emergency PD is a complex gesture prone to poor results. Postoperatively, the placement of a ductal stent by endoscopic retrograde catheterization may be decided, while management of an isolated pancreatic fistula is often straightforward. Non-operative management is the rule for the trauma victim who is hemodynamically stable. In addition to the clinical examination and conventional laboratory tests, investigations should include an abdominothoracic CT scan with contrast injection, allowing identification of all traumatized organs and assessment of the severity of injury. In this context, non-operative management (NOM) has gradually become the standard as long as the patient remains hemodynamically stable and there is no suspicion of injury to hollow viscera, with the patient being carefully monitored on a surgical service. The development of arteriography with splenic artery embolization has increased the rate of splenic salvage; this can be performed electively based on specific indications (blush on CT, pseudoaneurysm, arteriovenous fistula), and may also be considered for severe splenic injury, abundant hemoperitoneum, or severe polytrauma. For pancreatic injury, in addition to CT scan, magnetic resonance pancreatography (MRCP) or even endoscopic retrograde cholangiopancreatography (ERCP) may be necessary to identify a ductal rupture. If the pancreatic duct is intact, laboratory and CT imaging surveillance is performed just as for splenic injury. In case of pancreatic ductal injury, ERCP stenting can be considered. However, if this is unsuccessful, the therapeutic decision can be difficult: while NOM can still be successful, complications may arise that are difficult to treat while distal pancreatectomy, although initially more agressive may avoid these complications if performed early.

Management of penetrating abdominal and thoraco-abdominal wounds: A retrospective study of 186 patients.

This is a single center retrospective review of abdominal or abdomino-thoracic penetrating wounds treated between 2004 and 2013 in the gastrointestinal and emergency unit of the university hospital of Grenoble, France. This study did not include patients who sustained blunt trauma or non-traumatic wounds, as well as patients with penetrating head and neck injury, limb injury, ano-perineal injury, or isolated thoracic injury above the fifth costal interspace. In addition, we also included cases that were reviewed in emergency department morbidity and mortality conferences during the same period. Mortality was 5.9% (11/186 patients). Mean age was 36 years (range: 13-87). Seventy-eight percent (145 patients) suffered stab wounds. Most patients were hemodynamically stable or stabilized upon arrival at the hospital (163 patients: 87.6%). Six resuscitative thoracotomies were performed, five for gunshot wounds, one for a stab wound. When abdominal exploration was necessary, laparotomy was chosen most often (78/186: 41.9%), while laparoscopy was performed in 46 cases (24.7%), with conversion to laparotomy in nine cases. Abdominal penetration was found in 103 cases (55.4%) and thoracic penetration in 44 patients (23.7%). Twenty-nine patients (15.6%) had both thoracic and abdominal penetration (with 16 diaphragmatic wounds). Suicide attempts were recorded in 43 patients (23.1%), 31 (72.1%) with peritoneal penetration. Two patients (1.1%) required operation for delayed peritonitis, one who had had a laparotomy qualified as "negative", and another who had undergone surgical exploration of his wound under general anesthesia. In conclusion, management of clear-cut or suspected penetrating injury represents a medico-surgical challenge and requires effective management protocols.

Circadian rhythm of autophagy proteins in hippocampus is blunted by sleep fragmentation.

Autophagy is essential for normal cellular survival and activity. Circadian rhythms of autophagy have been studied in several peripheral organs but not yet reported in the brain. Here, we measured the circadian rhythm of autophagy-related proteins in mouse hippocampus and tested the effect of sleep fragmentation (SF). Expressions of the autophagy-related proteins microtubule-associated protein 1 light chain 3 (LC3) and beclin were determined by western blotting and immunohistochemistry. Both the hippocampal LC3 signal and the ratio of its lipid-conjugated form LC3-II to its cytosolic form LC3-I showed a 24 h rhythm. The peak was seen at ZT6 (1 pm) and the nadir at ZT16 (1 am). The LC3 immunoreactivity in hippocampal CA1 pyramidal neurons also distributed differently, with more diffuse cytoplasmic appearance at ZT16. Chronic SF had a mild effect to disrupt the 24 h rhythm of LC3 and beclin expression. Interestingly, a greater effect of SF was seen after 24 h of recovery sleep when LC3-II expression was attenuated at both the peak and trough of circadian activities. Overall, the results show for the first time that the hippocampus has a distinct rhythm of autophagy that can be altered by SF.

Management of pancreatic trauma.

INTRODUCTION: Pancreatic trauma (PT) is associated with high morbidity and mortality; the therapeutic options remain debated. MATERIAL AND METHODS: Retrospective study of PT treated in the University Hospital of Grenoble over a 22-year span. The decision for initial laparotomy depended on hemodynamic status as well as on associated lesions. Main pancreatic duct lesions were always searched for. PT lesions were graded according to the AAST classification. RESULTS: Of a total of 46 PT, 34 were grades II or I. Hemodynamic instability led to immediate laparotomy in 18 patients, for whom treatment was always drainage of the pancreatic bed; morbidity was 30%. Eight patients had grade III injuries, six of whom underwent immediate operation: three underwent splenopancreatectomy without any major complications while the other three who had simple drainage required re-operation for peritonitis, with one death related to pancreatic complications. Four patients had grades IV or V PT: two pancreatoduodenectomies were performed, with no major complication, while one patient underwent duodenal reconstruction with pancreatic drainage, complicated by pancreatic and duodenal fistula requiring a hospital stay of two months. The post-trauma course was complicated for all patients with main pancreatic duct involvement. Our outcomes were similar to those found in the literature. CONCLUSION: In patients with distal PT and main pancreatic duct involvement, simple drainage is associated with high morbidity and mortality. For proximal PT, the therapeutic options of drainage versus pancreatoduodenectomy must be weighed; pancreatoduodenectomy may be unavoidable when the duodenum is injured as well. Two-stage (resection first, reconstruction later) could be an effective alternative in the emergency setting when there are other associated traumatic lesions.

Role of Astrocytes in Leptin Signaling.

To test the hypothesis that astrocytic leptin signaling induces an overall potentiation of the neuronal response to leptin, we generated a new line of astrocyte-specific leptin receptor knockout (ALKO-Δ1) mice in which no leptin receptor is expressed in astrocytes. Corresponding to cell-specific Cre recombinase expression in hypothalamic astrocytes but not neurons, this new strain of ALKO mice had attenuated pSTAT3 signaling in the arcuate nucleus of the hypothalamus 30 min after intracerebroventricular delivery of leptin. In response to high-fat diet for 2 months, the ALKO mice showed a greater increase of percent fat and blood leptin concentration. This coincided with a mild reactive gliosis in the hypothalamus. Overall, the absence of leptin receptors in astrocytes attenuated hypothalamic pSTAT3 signaling, induced a mild reactive morphology, and promoted the development of diet-induced obesity. We conclude that leptin signaling in astrocytes is essential for the homeostasis of neuroendocrine regulation in obesity.

Sleep fragmentation has differential effects on obese and lean mice.

Chronic sleep fragmentation (SF), common in patients with sleep apnea, correlates with the development of obesity. We hypothesized that SF differentially affects neurobehavior in lean wild-type (WT) and obese pan-leptin receptor knockout (POKO) mice fed the same normal diet. First, we established an SF paradigm by interrupting sleep every 2 min during the inactive light span. The maneuver was effective in decreasing sleep duration and bout length, and in increasing sleep state transition and waking, without significant rebound sleep in the dark span. Changes of sleep architecture were evident in the light span and consistent across days 1-10 of SF. There was reduced NREM, shortened sleep latency, and increased state transitions. During the light span of the first day of SF, there also was reduction of REM and increased delta power of slow-wave sleep. Potential effects of SF on thermal pain threshold, locomotor activity, and anxiety were then tested. POKO mice had a lower circadian amplitude of pain latency than WT mice in the hot plate test, and both groups had lowest tolerance at 4 pm (zeitgeber time (ZT) 10) and longest latency at 4 am (ZT 22). SF increased the pain threshold in WT but not in POKO mice when tested at 8 a.m. (ZT 2). Both the POKO mutation and SF resulted in reduced physical activity and increased anxiety, but there was no additive effect of these two factors. Overall, SF and the POKO mutation differentially regulate mouse behavior. The results suggest that obesity can blunt neurobehavioral responses to SF.