Do nocturnal asthma attacks influence sleep parameters and inflammatory markers? A cross-sectional population-based study.

PURPOSE: To evaluate the effects of nocturnal asthma on sleep parameters and inflammatory markers according to the severity of the condition in participants in the São Paulo Epidemiologic Sleep Study (EPISONO). METHODS: Data from the 2007 and 2018 editions of the EPISONO study were utilized. Subjects completed validated sleep and respiratory questionnaires, underwent nocturnal polysomnography and spirometry tests, and provided blood samples for the assessment of inflammatory parameters. RESULTS: Of 72 participants (67% women), 53% (n = 38) had intermittent nocturnal asthma symptoms and 47% (n = 34) had persistent asthma (mild, moderate, and severe). Individuals with persistent nocturnal symptoms had a higher body mass index (BMI), were more likely to have respiratory symptoms, and had worse lung function, a higher apnea-hypopnea index (AHI), and higher desaturation index than individuals with intermittent nocturnal symptoms. Positive associations were identified between nocturnal asthma and obstructive sleep apnea (OSA). A higher frequency of OSA was observed in participants with persistent asthma and participants with OSA were more likely to have persistent than intermittent asthma. However, there were no significant differences between the immunological parameters of those with intermittent or persistent asthma. CONCLUSIONS: This study highlights the relevance of nocturnal symptoms as a valuable indicator of asthma severity. The findings also add to the existing body of evidence linking nocturnal asthma and OSA.

The effects of sleep deprivation and obstructive sleep apnea syndrome on male reproductive function: a multi-arm randomised trial.

Sleep is essential for the maintenance of health and systemic homeostasis. Decreased sleep time and sleep quality have been associated with a wide range of diseases. To evaluate the effects of obstructive sleep apnea (OSA) and total or selective rapid eye movement (REM) sleep deprivation on male reproductive function, we performed a three-arm parallel study with one pre-defined OSA group and a group of healthy volunteers who were then randomised into total or REM sleep deprivation groups. Questionnaires were completed and overnight polysomnography was undertaken, and blood and sperm samples were collected at the Sleep Institute, São Paulo, Brazil. OSA was diagnosed using questionnaires and polysomnography. Male sexual function was assessed through the questionnaires, blood tests, and semen samples. Data showed an association between OSA and lower circulating levels of total and free testosterone and high-density lipoproteins, as well as a lower proportion of healthy sperm cells and decreased sperm concentration, in comparison to volunteers. Volunteers subjected to either total or REM sleep deprivation had increased circulating levels of thyroid-stimulating hormone, insulin, and higher homeostatic model assessment of insulin resistance (HOMA-IR) values. Both sleep-deprived groups also shown decreased cholesterol, and low-density lipoproteins when compared to their baseline levels, but had no alterations in their spermograms. We observed a reduction in total testosterone following total sleep deprivation, but no effect after REM sleep deprivation. OSA was associated with a hormonal imbalance, which is probably linked with impaired reproductive function and associated comorbidities, such as sleep fragmentation/loss and obesity.

Effects of acute physical exercise in the light phase of sleep in rats with temporal lobe epilepsy.

OBJECTIVE: Our aim was to investigate the influence of an acute exercise session on sleep pattern in rats with temporal lobe epilepsy (TLE). METHODS: Twenty male Wistar rats were randomly assigned to 4 groups: control (C); acute exercise (EX); epilepsy (E) and epilepsy acute exercise (EEX). Two sleep electrocorticography recordings were performed during the light phase [baseline and day 2 (after the acute physical exercise session)]. After baseline recording, the exercise groups (EX and EEX) were submitted to an exercise session on a motor-driven treadmill at 12m/min for 30min. Twelve hours later, the rats were submitted to the second sleep recording. RESULTS: At baseline, the E group showed a higher wakefulness and a lower Total sleep time, Slow Wave Sleep and REM sleep compared with the C group. After acute exercise, there was an increase in Total sleep time and Slow Wave Sleep and a decrease of wakefulness in EEX (+11.10%, +20.29% and -11.25%, respectively) and EX (+5.20%, +11.60% and -8.12%, respectively) groups. CONCLUSION: These findings suggest that acute physical exercise positively impacts the sleep pattern of rats with TLE, inducing a more consolidated sleep.

Sleep restriction in Wistar rats impairs epididymal postnatal development and sperm motility in association with oxidative stress.

Good sleep quality has a direct effect on the activity of the neuroendocrine-reproductive control axis and oxidative stress. Thus, the aim of the present study was to evaluate whether sleep restriction (SR) during the peripubertal period impaired the postnatal development of the epididymis in Wistar rats. After 21 days SR (18h per day), epididymides were collected on Postnatal Day (PND) 62 for evaluation of oxidative stress markers, inflammatory profile, sperm count and histopathological and stereological analyses; in addition, the motility of spermatozoa from the vas deferens was examined. SR significantly increased lipid peroxidation and glutathione levels in the caput and cauda epididymidis, and increased levels of total radical-trapping antioxidant potential in the caput epididymidis only. Neutrophil migration to the caput or corpus epididymidis was decreased by SR, and the size of the luminal compartment in the 2A region and the epithelial compartment in the 5A/B region was also decreased. In these regions, there was an increase in the size of the interstitial compartment. The percentage of immotile spermatozoa was higher in the SR group. In conclusion, SR affects epididymal postnatal development, as well as sperm motility, in association with increased oxidative stress and a decrease in the size of the epithelial compartment in the cauda epididymidis.

Impairment of male reproductive function after sleep deprivation.

OBJECTIVE: To evaluate the influence of sleep loss on sexual behavior, hormone levels, sperm parameters, and testis-specific gene expression in male rats. DESIGN: Experimental research. SETTING: Animal laboratory. ANIMAL(S): Male adult Wistar-Hannover rats. INTERVENTION(S): Sexually experienced rats were subjected to paradoxic sleep deprivation (PSD) for 96 hours or sleep restriction (SR) for 21 days or kept in their home cage as control (CTRL). MAIN OUTCOME MEASURE(S): Sexual behavior, hormone levels, sperm parameters and expression of stress and nitric oxide-related genes were evaluated. RESULT(S): PSD significantly decreased sexual behavior compared with the CTRL group, whereas SR had no effect. The PSD group had significantly lower testosterone levels than the CTRL group. Both PSD and SR groups had lower sperm viabilities than the CTRL group. The decrease in the number of live sperm compared with the CTRL group was larger in the PSD group than in the SR group. Regarding testicular gene expression, both PSD and SR led to an increase of iNOS and hydroxysteroid 11ß-dehydrogenase 1 expressions compared with the CTRL group. These changes were more pronounced in the PSD group. A significant increase in endothelial nitric oxide synthase expression was observed in the PSD groups compared with the CTRL group. No changes were observed in dimethylarginine dimethylaminohydrolase 1 and casein kinase 2ß-polypeptide expressions. CONCLUSION(S): Sleep loss can promote marked changes in the male reproductive system of rats, particularly affecting spermatic function in part by interfering in the testicular nitric oxide pathway.

The influence of sleep restriction on expression of apoptosis regulatory proteins p53, Bcl-2 and Bax following rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide.

PURPOSE: The aim of this study was to evaluate whether sleep restriction (SR) could affect the mechanisms and pathways' essentials for cancer cells in tongue cancer induced by 4-nitroquinoline 1-oxide in Wistar rats. METHODS: The animals were distributed into 4 groups of 5 animals each treated with 50 ppm 4 NQO solution through their drinking water for 4 and 12 weeks. The animals were submitted to sleep restriction for 21 days using the modified multiple platform method, which consisted of placing 5 rats in a cage (41 × 34 × 16 cm) containing 10 circular platforms (3.5 cm in diameter) with water 1 cm below the upper surface. The investigations were conducted using immunohistochemistry of p53, Bax and Bcl-2 proteins related to apoptosis and its pathways. RESULTS: Although no histopathologic abnormalities were induced in the epithelium after 4 weeks of carcinogen exposure in all groups, in 12 weeks were observed pre-neoplastic lesions. Data analysis revealed statistically significant differences (P < 0.05) in 4 weeks group for p53, and for bcl-2. Following 12 weeks of 4NQO administration, we found significant differences between SR and control groups in p53, bax, and bcl-2 immunoexpression. CONCLUSION: Our results reveal that sleep restriction exerted alterations in proteins associated with proliferation and apoptosis in carcinogenesis.

Anxiety-like effects of meta-chlorophenylpiperazine in paradoxically sleep-deprived mice.

Chlorophenylpiperazines (CPP) are psychotropic drugs used in nightclub parties and are frequently used in a state of sleep deprivation, a condition which can potentiate the effects of psychoactive drugs. This study aimed to investigate the effects of sleep deprivation and sleep rebound (RB) on anxiety-like measures in mCPP-treated mice using the open field test. We first optimized our procedure by performing dose-effect curves and examining different pretreatment times in naïve male Swiss mice. Subsequently, a separate cohort of mice underwent paradoxical sleep deprivation (PSD) for 24 or 48h. In the last experiment, immediately after the 24h-PSD period, mice received an injection of saline or mCPP, but their general activity was quantified in the open field only after the RB period (24 or 48h). The dose of 5mgmL(-1) of mCPP was the most effective at decreasing rearing behavior, with peak effects 15min after injection. PSD decreased locomotion and rearing behaviors, thereby inhibiting a further impairment induced by mCPP. Plasma concentrations of mCPP were significantly higher in PSD 48h animals compared to the non-PSD control group. Twenty-four hours of RB combined with mCPP administration produced a slight reduction in locomotion. Our results show that mCPP was able to significantly change the behavior of naïve, PSD, and RB mice. When combined with sleep deprivation, there was a higher availability of drug in plasma levels. Taken together, our results suggest that sleep loss can enhance the behavioral effects of the potent psychoactive drug, mCPP, even after a period of rebound sleep.

Effects of sleep deprivation during pregnancy on the reproductive capability of the offspring.

OBJECTIVE: To investigate the effects of sleep deprivation during pregnancy on the reproductive capability of the offspring. DESIGN: Using a sleep loss model or control home-cage group (male and females rats) to evaluate sexual behavior and hormonal profile in males and females F1 offspring. SETTING: Laboratory. ANIMALS(S): First experiment: Pregnant females were exposed to sleep restriction (SR) protocol and the F1 generation was evaluated. Second experiment: male rats were submitted to SR or paradoxical sleep deprivation (PSD) protocol and the F1 generation was evaluated. INTERVENTION(S): Male and female rats were subjected to sleep restriction (SR) for 21 days or paradoxal sleep-deprived (PSD) for 96 hours. MAIN OUTCOME MEASURE(S): Sexual behavior and hormonal levels during the adult phase were analyzed in F1 offspring of female and male rats submitted to sleep loss. RESULT(S): F1 male offspring of SR females had lower motivation for sex and reduced progesterone concentrations. In contrast, F1 female offspring displayed significantly enhanced proceptivity compared with control offspring. F1 female offspring also demonstrated hypersexuality by mounting the males in the absence of any significant hormonal alterations. F1 male offspring of SR or paradoxically sleep-deprived (PSD) males presented a decline in the sexual response, accompanied by a reduction in testosterone concentrations. Proceptivity was significantly increased among F1 female offspring of PSD and SR males compared with control offspring. CONCLUSION(S): SR in progenitors may alter sexual behavior of the F1 offspring in adulthood. These findings reveal far-reaching consequences of sleep deprivation, and suggest that parental sleep influences the reproductive capability of subsequent generations.

Modafinil ameliorates cognitive deficits induced by maternal separation and sleep deprivation.

Animals exposed to an early adverse event may be more susceptible to a second source of stress later in life, and these stressors may have additive deleterious effects. Sleep deprivation is known to be a stressor, affecting multiple body functions such as the cognition. Modafinil enhances working memory and attention in healthy non-sleep deprived subjects and in animal models of sleep deprivation. The first aim of the present study was to investigate the effects of maternal separation (MS) combined with paradoxical sleep deprivation (PSD) in adulthood on recognition memory in rats. Second, we aimed to evaluate whether the administration of modafinil would be able to ameliorate memory deficits induced by MS and PSD. Wistar rat pups were initially distributed into MS and handling (H) groups, with their litters standardized in 4 females and 4 males. In adulthood, the male rats were submitted to PSD or control condition, being redistributed afterwards in modafinil- or vehicle-treatment immediately after the training session of object recognition task. PSD did not potentiate the cognitive deficit due to MS. However, modafinil was able to recover memory impairments associated to PSD and also to MS in the neonatal period. This study demonstrates for the first time that modafinil ameliorates cognitive deficits associated to MS and to PSD in adulthood, independent from MS in the neonatal period.

The influence of sleep deprivation on expression of apoptosis regulatory proteins p53, bcl-2 and bax following rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide.

BACKGROUND: The aim of this study was to evaluate whether paradoxical sleep deprivation could affects the mechanisms and pathways essentials for cancer cells in tongue cancer induced by 4-nitroquinole 1-oxide in Wistar rats. MATERIALS AND METHODS: For this purpose, the animals were distributed into 4 groups of 5 animals each treated with 50 ppm 4 nitroquinoline 1 oxide (4 NQO) solution through their drinking water for 4 and 12 weeks. The animals were submitted to paradoxical sleep deprivation (PSD) for 72 h using the modified multiple platform method, which consisted of placing 5 mice in a cage (41 × 34 × 16 cm) containing 10 circular platforms (3.5 cm in diameter) with water 1 cm below the upper surface. The investigations were conducted using immunohistochemistry of p53, Bax and Bcl-2 proteins related to apoptosis and its pathways. Statistical analysis was performed by Kruskal-Wallis non-parametric test followed by the Dunn's test using SPSS software pack (version 1.0). P value < 0.05 was considered for statistic significance. RESULTS: Although no histopathological abnormalities were induced in the epithelium after 4 weeks of carcinogen exposure in all groups, in 12 weeks were observed pre-neoplasic lesions. Data analysis revealed statistically significant differences (P < 0.05) in 4 weeks group for p53 and for bcl-2 and for all immunomarkers after 12 weeks of 4NQO administration. CONCLUSION: Our results reveal that sleep deprivation exerted alterations in proteins associated with proliferation and apoptosis in carcinogenesis.

The influence of sleep deprivation and obesity on DNA damage in female Zucker rats.

OBJECTIVE: The aim of this study was to evaluate overall genetic damage induced by total sleep deprivation in obese, female Zucker rats of differing ages. METHOD: Lean and obese Zucker rats at 3, 6, and 15 months old were randomly distributed into two groups for each age group: home-cage control and sleep-deprived (N = 5/group). The sleep-deprived groups were deprived sleep by gentle handling for 6 hours, whereas the home-cage control group was allowed to remain undisturbed in their home-cage. At the end of the sleep deprivation period, or after an equivalent amount of time for the home-cage control groups, the rats were brought to an adjacent room and decapitated. The blood, brain, and liver tissue were collected and stored individually to evaluate DNA damage. RESULTS: Significant genetic damage was observed only in 15-month-old rats. Genetic damage was present in the liver cells from sleep-deprived obese rats compared with lean rats in the same condition. Sleep deprivation was associated with genetic damage in brain cells regardless of obesity status. DNA damage was observed in the peripheral blood cells regardless of sleep condition or obesity status. CONCLUSION: Taken together, these results suggest that obesity was associated with genetic damage in liver cells, whereas sleep deprivation was associated with DNA damage in brain cells. These results also indicate that there is no synergistic effect of these noxious conditions on the overall level of genetic damage. In addition, the level of DNA damage was significantly higher in 15-month-old rats compared to younger rats.

Sexual response in female rats with status epilepticus.

PURPOSE: Female sexual function is complex and may be disrupted by disease, in particular epilepsy. Chronic seizures in women can have adverse effects on reproductive function, but it has been difficult to dissociate the effects of epilepsy from those related to anticonvulsant medications. The purpose of this study was to evaluate sexual behavior in female rats submitted to pilocarpine-induced status epilepticus (SE). METHODS: Adult female Wistar rats were given saline or pilocarpine (350 mg/kg, i.p.) to induce SE. The groups were distributed according to the treatment or response to pilocarpine: CTRL (control rats maintained in the home-cage after saline administration); NSE (non-status epilepticus, rats that did not display convulsive and intermittent seizures after pilocarpine injection) and SE (status epilepticus, rats that displayed convulsive and intermittent seizures after pilocarpine injection). After 50 days, sexual receptivity in the female rats was artificially induced via administration of a combination of estradiol and progesterone. Sexual behavior was evaluated during three sessions in the presence of a sexually experienced male rat. Receptivity and proceptivity behaviors, as well as hormones concentrations, were monitored. KEY FINDINGS: Significant decreases in proceptivity and receptivity behaviors during the three tests were observed in SE female rats. The rejection response was significantly increased in SE rats compared with CTRL or NSE groups. Progesterone, testosterone, and corticosterone were unchanged between the groups. SIGNIFICANCE: The SE female rats showed lower sexual motivation and performance regardless of their steroid hormones levels.

Influence of acute sleep deprivation on cardiovascular parameters in female Zucker obese and lean rats.

OBJECTIVE: There is a reciprocal relationship between sleep duration and weight gain. However, the consequences of this relationship on the cardiovascular system over an entire life span are still not fully elucidated. We examined the effect of acute sleep deprivation (SD) on baroreflex sensitivity and blood pressure in Zucker rats of different ages. DESIGN AND METHODS: Female lean and obese Zucker rats at 3, 6 and 15 months of age were assigned to SD or control (CTRL) groups. After a 6 h period of the SD procedure (6 h of gentle handling) or CTRL procedure (an equivalent period without handling), the animals were anesthetized for surgical catheterization of the femoral artery and vein. To evaluate the baroreflex sensitivity index, bolus infusions of phenylephrine (bradycardia response) and sodium nitroprusside (tachycardia response) were administered. RESULTS: Obesity resulted in dysfunctional tachycardia responses at 3 months of age. At 6 and 15 months of age, both bradycardia and tachycardia responses were significantly lower in obese animals than those in lean animals. At 15 months of age, interactions among obesity, SD and aging produced the most marked effects on the cardiovascular system (increased mean arterial pressure and heart rate and decreased baroreflex sensitivity). CONCLUSIONS: Therefore, these results suggest that there is no direct relationship between baroreflex imbalance and an increase in arterial pressure.

The influence of sleep deprivation and obesity on DNA damage in female Zucker rats

OBJECTIVE: The aim of this study was to evaluate overall genetic damage induced by total sleep deprivation in obese, female Zucker rats of differing ages. METHOD: Lean and obese Zucker rats at 3, 6, and 15 months old were randomly distributed into two groups for each age group: home-cage control and sleep-deprived (N = 5/group). The sleep-deprived groups were deprived sleep by gentle handling for 6 hours, whereas the home-cage control group was allowed to remain undisturbed in their home-cage. At the end of the sleep deprivation period, or after an equivalent amount of time for the home-cage control groups, the rats were brought to an adjacent room and decapitated. The blood, brain, and liver tissue were collected and stored individually to evaluate DNA damage. RESULTS: Significant genetic damage was observed only in 15-month-old rats. Genetic damage was present in the liver cells from sleep-deprived obese rats compared with lean rats in the same condition. Sleep deprivation was associated with genetic damage in brain cells regardless of obesity status. DNA damage was observed in the peripheral blood cells regardless of sleep condition or obesity status. CONCLUSION: Taken together, these results suggest that obesity was associated with genetic damage in liver cells, whereas sleep deprivation was associated with DNA damage in brain cells. These results also indicate that there is no synergistic effect of these noxious conditions on the overall level of genetic damage. In addition, the level of DNA damage was significantly higher in 15-month-old rats compared to younger rats.

Impairment of sexual function in rats with epilepsy.

INTRODUCTION: Epilepsy is a chronic disease that affects men and women of all ages, with different levels of severity. Many individuals with epilepsy also suffer from impairments in sexual function. However, it is difficult to differentiate between the impact of the disease and the impact of antiepileptic drugs on sexual function in human subjects. AIMS: To evaluate sexual behavior in adult male rats submitted to chronic pilocarpine-induced epilepsy. METHODS: First, non-epileptic rats were exposed to nine training sessions to acquire sexual experience, and their baseline sexual performance was evaluated. Then, the same rats were given pilocarpine to induce status epilepticus followed by chronic epilepsy. Once the animals had developed spontaneous recurrent seizures, their sexual behavior was evaluated during three sessions. MAIN OUTCOME MEASURES: Examine changes in latencies to first mount, intromission, and ejaculation, and the total number of mounts, intromissions, and ejaculations. RESULTS: All outcome measures related to sexual motivation and sexual performance were markedly impaired during chronic epilepsy compared with the baseline and the control group. CONCLUSION: These findings will aid in understanding the interaction between sexual behavior and epilepsy, as well as encouraging further experimental studies in human patients with epilepsy suffering from sexual dysfunction.

Influence of food restriction on lipid profile and spontaneous glucose levels in male rats subjected to paradoxical sleep deprivation.

OBJECTIVES: The purpose of this study was to determine the paired consequences of food restriction and paradoxical sleep deprivation on lipid profile and spontaneous glucose levels in male rats. METHOD: Food restriction began at weaning, with 6 g of food being provided per day, which was subsequently increased by 1 g per week until reaching 15 g per day by the eighth week. At adulthood, both rats subjected to food restriction and those fed ad libitum were exposed to paradoxical sleep deprivation for 96 h or were maintained in their home-cage groups. RESULTS: Animals subjected to food restriction exhibited a significant increase in high-density lipoprotein levels compared to animals that were given free access to food. After the paradoxical sleep deprivation period, the food-restricted animals demonstrated reduced concentrations of high-density lipoprotein relative to their respective controls, although the values for the food-restricted animals after sleep deprivation were still higher than those for the ad libitum group. The concentration of low-density lipoproteins was significantly increased in sleep-deprived animals fed the ad libitum diet. The levels of triglycerides, very low-density lipoproteins, and glucose in food-restricted animals were each decreased compared to both ad libitum groups. CONCLUSION: These results may help to illustrate the mechanisms underlying the relationship between sleep curtailment and metabolism and may suggest that, regardless of sleep deprivation, dietary restriction can minimize alterations in parameters related to cardiovascular risk.

Behavioral and genetic effects promoted by sleep deprivation in rats submitted to pilocarpine-induced status epilepticus.

The interaction between sleep deprivation and epilepsy has been well described in electrophysiological studies, but the mechanisms underlying this association remain unclear. The present study evaluated the effects of sleep deprivation on locomotor activity and genetic damage in the brains of rats treated with saline or pilocarpine-induced status epilepticus (SE). After 50 days of pilocarpine or saline treatment, both groups were assigned randomly to total sleep deprivation (TSD) for 6 h, paradoxical sleep deprivation (PSD) for 24 h, or be kept in their home cages. Locomotor activity was assessed with the open field test followed by resection of brain for quantification of genetic damage by the single cell gel electrophoresis (comet) assay. Status epilepticus induced significant hyperactivity in the open field test and caused genetic damage in the brain. Sleep deprivation procedures (TSD and PSD) did not affect locomotor activity in epileptic or healthy rats, but resulted in significant DNA damage in brain cells. Although PSD had this effect in both vehicle and epileptic groups, TSD caused DNA damage only in epileptic rats. In conclusion, our results revealed that, despite a lack of behavioral effects of sleep deprivation, TSD and PSD induced genetic damage in rats submitted to pilocarpine-induced SE.

Inhibition of self-grooming induced by sleep restriction in dam rats.

BACKGROUND & OBJECTIVES: Sleep restriction is a common feature of modern lifestyle and its effects can be extended to pregnancy. Several neurobehavioural consequences of sleep restriction during pregnancy have been reported, among which stand out perinatal depression and maternal fatigue, however, its effects over mother-infant relationship warrant further investigation. Thus, this study was aimed to evaluate the effects of sleep restriction during pregnancy over maternal behaviour and maternal aggression through animal models. METHODS: Eighteen 90-day-old female Wistar rats were distributed in two groups: (i) Control - not submitted to any manipulation during pregnancy, and (ii) Sleep restriction - submitted to sleep restriction during the entire pregnancy (21 days) through the multiple platforms technique. In the postpartum day 5, resident-intruder paradigm and the latencies test were performed to assess both maternal behaviour and maternal aggression. RESULTS: The sleep-restricted females displayed grooming in less frequency and duration, and with higher latency when compared to normal animals, while maternal aggression and maternal behaviour parameters remained equivalent between groups. INTERPRETATION & CONCLUSIONS: Considering the maintenance of maternal behavioural parameters, the inhibition of grooming seems to exert an adaptive mechanism, enabling sleep-restricted rats to display maternal behaviour properly.

Influence of food restriction on lipid profile and spontaneous glucose levels in male rats subjected to paradoxical sleep deprivation

OBJECTIVES: The purpose of this study was to determine the paired consequences of food restriction and paradoxical sleep deprivation on lipid profile and spontaneous glucose levels in male rats. METHOD: Food restriction began at weaning, with 6 g of food being provided per day, which was subsequently increased by 1 g per week until reaching 15 g per day by the eighth week. At adulthood, both rats subjected to food restriction and those fed ad libitum were exposed to paradoxical sleep deprivation for 96 h or were maintained in their home-cage groups. RESULTS: Animals subjected to food restriction exhibited a significant increase in high-density lipoprotein levels compared to animals that were given free access to food. After the paradoxical sleep deprivation period, the foodrestricted animals demonstrated reduced concentrations of high-density lipoprotein relative to their respective controls, although the values for the food-restricted animals after sleep deprivation were still higher than those for the ad libitum group. The concentration of low-density lipoproteins was significantly increased in sleep-deprived animals fed the ad libitum diet. The levels of triglycerides, very low-density lipoproteins, and glucose in foodrestricted animals were each decreased compared to both ad libitum groups. CONCLUSION: These results may help to illustrate the mechanisms underlying the relationship between sleep curtailment and metabolism and may suggest that, regardless of sleep deprivation, dietary restriction can minimize alterations in parameters related to cardiovascular risk.