Sleep pattern in an experimental model of chronic kidney disease

Poor sleep quality and associated factors among adult chronic kidney disease patients

Background

Poor sleep quality is a common concern in chronic kidney disease (CKD) patients, which can accelerate the progression of chronic renal disease and negatively impact their health-related quality of life, potentially leading to greater morbidity and mortality rates. It can also have an effect on the immune system, cognitive function, and emotional well-being of CKD patients. Furthermore, poor sleep quality may contribute to drug noncompliance and decreased participation in the entire treatment plan. Nonetheless, no research has been undertaken in Ethiopia on the prevalence of poor sleep quality and its associated factors among CKD patients.

Objective

This study aimed to assess the prevalence of poor quality of sleep and associated factors among chronic kidney disease patients at the University of Gondar Comprehensive Specialized and Felege Hiwot Referral Hospitals in 2020.

Methods

A cross-sectional study design was implemented at the University of Gondar Comprehensive Specialized and Felege Hiwot Referral Hospitals between February and April 2020. The study participants were chosen through systematic random sampling techniques. The Pittsburgh Sleep Quality Index (PSQI), a validated assessment tool, was utilized to measure sleep quality. A PSQI total score > 5 was used as an indicator of poor sleep quality. Subsequently, the data obtained were entered into Epi Data version 3.0 and then transferred to STATA 14 for analysis. Both bivariable and multivariable binary logistic regression analyses were performed to recognize factors associated with poor sleep quality. In the multivariable logistic regression analysis, variables demonstrating a p-value of ≤0.05 were considered statistically associated to poor sleep quality.

Results

In this study, 424 CKD patients were included. Among screened CKD patients, 42.9% tested positive for poor sleep quality with a 95% CI (38 to 47%). Independent predictors of poor sleep quality among CKD patients were common mental disorder [AOR = 1.8, 95% CI (1.19-2.89)], anemia [AOR = 2.7, 95% CI (1.71-4.36)], declined eGFR between 60 and 89.9 [AOR = 1.6; 95% CI (2.28-5.54)], 30-59.9 [AOR = 2.6, 95% CI (1.53-4.43)], and ≤ 30 [AOR = 3.8, 95% CI (1.17-12.61)], age > 50 years [AOR = 1.7(1.11-2.69)] and duration of disease 2.9 [AOR = 2.9, 95% CI (1.77-4.90)].

Conclusion

In our study, almost 1 out of 2 CKD patients assessed for poor sleep quality tested positive. It was noted that poor sleep quality was more frequent among CKD patients with common mental disorders, anemia, decreased eGFR levels, individuals aged over 50 years, and those with a longer duration of the disease. Consequently, it's advised to regularly screen these CKD patients for poor sleep quality.

Chronic kidney disease may evoke anxiety by altering CRH expression in the amygdala and tryptophan metabolism in rats

Chronic kidney disease (CKD) is associated with anxiety; however, its exact mechanism is not well understood. Therefore, the aim of the present study was to assess the effect of moderate CKD on anxiety in rats. 5/6 nephrectomy was performed in male Wistar rats. 7 weeks after, anxiety-like behavior was assessed by elevated plus maze (EPM), open field (OF), and marble burying (MB) tests. At weeks 8 and 9, urinalysis was performed, and blood and amygdala samples were collected, respectively. In the amygdala, the gene expression of Avp and the gene and protein expression of Crh, Crhr1, and Crhr2 were analyzed. Furthermore, the plasma concentration of corticosterone, uremic toxins, and tryptophan metabolites was measured by UHPLC-MS/MS. Laboratory tests confirmed the development of CKD. In the CKD group, the closed arm time increased; the central time and the total number of entries decreased in the EPM. There was a reduction in rearing, central distance and time in the OF, and fewer interactions with marbles were detected during MB. CKD evoked an upregulation of gene expression of Crh, Crhr1, and Crhr2, but not Avp, in the amygdala. However, there was no alteration in protein expression. In the CKD group, plasma concentrations of p-cresyl-sulfate, indoxyl-sulfate, kynurenine, kynurenic acid, 3-hydroxykynurenine, anthranilic acid, xanthurenic acid, 5-hydroxyindoleacetic acid, picolinic acid, and quinolinic acid increased. However, the levels of tryptophan, tryptamine, 5-hydroxytryptophan, serotonin, and tyrosine decreased. In conclusion, moderate CKD evoked anxiety-like behavior that might be mediated by the accumulation of uremic toxins and metabolites of the kynurenine pathway, but the contribution of the amygdalar CRH system to the development of anxiety seems to be negligible at this stage.

Effects of Melatonin on Salivary Levels of Cortisol and Sleep Quality of Hemodialysis Patients: A Randomized Clinical Trial

Objective: The aim of this study was to investigate the effects of exogenous melatonin on the quality of sleep in patients undergoing dialysis and to investigate its mechanism for the regulation of total circadian rhythm and salivary levels of cortisol in hemodialysis patients admitted to Pange Azar hospital in Gorgan in winter of 2017.

Method: This was a double-blind randomized clinical trial. Samples were transferred to the laboratory by maintaining the cold chain. Then, the patients were divided into two groups. In a double-blind trial, one group received three mg melatonin and another group received placebo for two weeks at 10 PM. At the end of two weeks, sampling was performed to investigate the salivary level of cortisol under the same conditions. The research instrument was Pittsburgh questionnaire. Data were analyzed before and after intervention using SPSS 16 software.

Results: Salivary levels of cortisol decreased significantly after the intervention in the melatonin group (melatonin: 1.40 ± 1.82 and placebo: 4.94 ± 4.43; P = 0.008). Salivary levels of cortisol in the morning after intervention were also lower in the melatonin group, but were not statistically significant (melatonin 3.99 ± 3.45 and placebo: 5.35 ± 4.9; P = 0.93). Also, the difference in salivary levels of cortisol at night and before and after intervention significantly decreased in melatonin group. PSQI difference (interventional dimension) and PSQI (before intervention) were significantly decreased in melatonin group (P = 0.0001). The rate of change in the subscales of sleep latency, sleep efficiency, and sleep disorders in the melatonin group than in the placebo group was significantly higher.

Conclusion: Melatonin can be used as a safe and cost-effective treatment to improve sleep quality and can also reduce salivary cortisol increased in hemodialysis patients at night.

Home-based versus center-based aerobic exercise on cardiopulmonary performance, physical function, quality of life and quality of sleep of overweight patients with chronic kidney disease

BACKGROUND

The association between chronic kidney disease (CKD) and obesity can decrease the patients' cardiopulmonary capacity, physical functioning and quality of life. The search for effective and practical alternative methods of exercise to engage patients in training programs is of great importance. Therefore, we aimed to compare the effects of home-based versus center-based aerobic exercise on the cardiopulmonary and functional capacities, quality of life and quality of sleep of overweight non-dialysis-dependent patients with CKD (NDD-CKD).

METHODS

Forty sedentary overweight patients CKD stages 3 and 4 were randomly assigned to an exercise group [home-based group (n = 12) or center-based exercise group (n = 13)] or to a control group (n = 15) that did not perform any exercise. Cardiopulmonary exercise test, functional capacity tests, quality of life, quality of sleep and clinical parameters were assessed at baseline, 12 and 24 weeks.

RESULTS

The VO_2peak and all cardiopulmonary parameters evaluated were similarly improved (p < 0.05) after 12 and 24 weeks in both exercise groups. The functional capacity tests improved during the follow-up in the home-based group (p < 0.05) and reached values similar to those obtained in the center-based group. The benefits achieved in both exercise groups were also reflected in improvement of quality of life and sleep (p < 0.05). No differences were observed between the exercise groups, and no changes in any of the parameters investigated were found in the control group.

CONCLUSION

Home-based aerobic training was as effective as center-based training in improving the physical and functional capabilities, quality of life and sleep in overweight NDD-CKD patients.

Recommendations for Development of Botanical Polyphenols as "Natural Drugs" for Promotion of Resilience Against Stress-Induced Depression and Cognitive Impairment

Extensive evidence has demonstrated that psychological stress has detrimental effects on psychological health, cognitive function, and ultimately well-being. While stressful events are a significant cause of psychopathology, most individuals exposed to adversity maintain normal psychological functioning. The mechanisms underlying such resilience are poorly understood, and there is an urgent need to identify and target these mechanisms to promote resilience under stressful events. Botanicals have been used throughout history to treat various medical conditions; however, the development of botanical compounds into potential preventative and therapeutic agents in studies promoting brain health is hindered by the fact that most orally consumed botanicals are extensively metabolized during absorption and/or by post-absorptive xenobiotic metabolism. Therefore, the primary objective of this review article is to provide recommendations for developing natural compounds as novel therapeutic strategies to promote resilience in susceptible subjects. The development of botanical polyphenols to ultimately attenuate mood disorders and cognitive impairment will rely on understanding (1) the absorption and bioavailability of botanical polyphenols with emphasis on flavan-3-ols, (2) the characterization of tissue-specific accumulation of biologically available polyphenols and their mechanisms of action in the brain, and eventually (3) the characterization of biologically available polyphenol metabolites in mechanisms associated with the promotion of resilience against mood disorders and cognitive impairment in response to stress. We also summarize exciting new lines of investigation about the role of botanicals such as polyphenols in the promotion of cognitive and psychological resilience. This information will provide a strategical framework for the future development of botanicals as therapeutic agents to promote resilience, ultimately preventing and/or therapeutically treating cognitive impairment and psychological dysfunction.

Novel application of brain-targeting polyphenol compounds in sleep deprivation-induced cognitive dysfunction

Sleep deprivation produces deficits in hippocampal synaptic plasticity and hippocampal-dependent memory storage. Recent evidence suggests that sleep deprivation disrupts memory consolidation through multiple mechanisms, including the down-regulation of the cAMP-response element-binding protein (CREB) and of mammalian target of rapamycin (mTOR) signaling. In this study, we tested the effects of a Bioactive Dietary Polyphenol Preparation (BDPP), comprised of grape seed polyphenol extract, Concord grape juice, and resveratrol, on the attenuation of sleep deprivation-induced cognitive impairment. We found that BDPP significantly improves sleep deprivation-induced contextual memory deficits, possibly through the activation of CREB and mTOR signaling pathways. We also identified brain-available polyphenol metabolites from BDPP, among which quercetin-3-O-glucuronide activates CREB signaling and malvidin-3-O-glucoside activates mTOR signaling. In combination, quercetin and malvidin-glucoside significantly attenuated sleep deprivation-induced cognitive impairment in -a mouse model of acute sleep deprivation. Our data suggests the feasibility of using select brain-targeting polyphenol compounds derived from BDPP as potential therapeutic agents in promoting resilience against sleep deprivation-induced cognitive dysfunction.

Nonapnea sleep disorders and incident chronic kidney disease: a population-based retrospective cohort study

Nonapnea sleep disorders (NASDs) are associated with an increased risk of stroke, diabetes, and hypertension. No longitudinal study has yet examined the association between NASD and chronic kidney disease (CKD) by using epidemiologic study methods. To test this hypothesis, we examined the effect of NASD on the incidence of CKD in a large population-based retrospective cohort study. Based on a retrospective cohort study of a general population sample of 128 to 436 patients in the Taiwan National Health Insurance Research Database from January 1, 1998 to December 31, 2001, 42 to 812 NASD patients were followed up for 10.2 ± 3.12 years, and additional 85 to 624 individuals had no NASD at baseline. The International Classification of Diseases, Ninth Revision, Clinical Modification was used to identify the diagnosis of disease. Cox proportional hazard regression models were used to assess the association between NASD and subsequent CKD risk. The incidence rate of CKD was significantly higher in the NASD cohort than in the comparison cohort (2.68 vs 1.88 per 1000 person-years, respectively). After we adjusted for age, sex, and comorbidities, the risk of developing CKD was significant for patients with NASD (adjusted hazard ratio [HR] = 1.13; 95% confidence interval [CI] = 1.05-1.22; P < 0.01). Among different types of NASDs, patients with sleep disturbance associated disorders had a 14% increased risk of developing CKD (95% CI = 1.03-1.26; P < 0.01), whereas patients with insomnia had a 13% increased risk of subsequent CKD (95% CI = 1.02-1.25; P < 0.05) compared with the non-NASD cohort. Kaplan-Meier survival analysis indicated that the CKD-free rate was 1% lower in the NASD cohort than in the comparison cohort (log-rank test, P < 0.0001). Our study provides evidence that patients with NASD have an increased risk of developing subsequent CKD compared with patients without NASD; men, elderly people, and patients with concomitant comorbidities are at the greatest risk.

The impact of sleep loss on hippocampal function

Hippocampal cellular and molecular processes critical for memory consolidation are affected by the amount and quality of sleep attained. Questions remain with regard to how sleep enhances memory, what parameters of sleep after learning are optimal for memory consolidation, and what underlying hippocampal molecular players are targeted by sleep deprivation to impair memory consolidation and plasticity. In this review, we address these topics with a focus on the detrimental effects of post-learning sleep deprivation on memory consolidation. Obtaining adequate sleep is challenging in a society that values "work around the clock." Therefore, the development of interventions to combat the negative cognitive effects of sleep deprivation is key. However, there are a limited number of therapeutics that are able to enhance cognition in the face of insufficient sleep. The identification of molecular pathways implicated in the deleterious effects of sleep deprivation on memory could potentially yield new targets for the development of more effective drugs.

Effects of acute systemic administration of cannabidiol on sleep-wake cycle in rats

Cannabidiol (CBD) is one of the main components of Cannabis sativa and has a wide spectrum of action, including effects in the sleep-wake cycle.

OBJECTIVE

The objective of this paper is to assess the effects on sleep of acute systemic administration of CBD.

METHOD

Adult male Wistar rats were randomly distributed into four groups that received intraperitoneal injections of CBD 2.5 mg/kg, CBD 10 mg/kg, CBD 40 mg/kg or vehicle (n=seven animals/group). Sleep recordings were made during light and dark periods for four days: two days of baseline recording, one day of drug administration (test), and one day after drug (post-test).

RESULTS

During the light period of the test day, the total percentage of sleep significantly increased in the groups treated with 10 and 40 mg/kg of CBD compared to placebo. REM sleep latency increased in the group injected with CBD 40 mg/kg and was significantly decreased with the dose of 10 mg/kg on the post-test day. There was an increase in the time of SWS in the group treated with CBD 40 mg/kg, although this result did not reach statistical significance.

CONCLUSION

The systemic acute administration of CBD appears to increase total sleep time, in addition to increasing sleep latency in the light period of the day of administration.

Potential biochemical pathways for the relationship between sleep duration and mortality

OBJECTIVE

The objective of this study was to elucidate new evidence on the presence of a relationship among sleep duration, cardiovascular mortality and total mortality, and to investigate sleep duration-related multiple biochemical changes.

METHODS

The longitudinal study is based on the SAKUCESS study of 12,489 residents of Japan aged 20-79 years at baseline.

RESULTS

In the study, compared to respondents who reported 7h of sleep, long sleep duration (≥9h) was associated with an increased risk of cardiovascular disease mortality and total mortality in men, hazard ratios (HRs) were 1.70 (95% confidence interval [CI]=1.07-2.70) and 2.73 (95% CI=1.22-6.11) and an increased risk of total mortality in women, HR was 1.85 (95% CI=1.09-3.13). Sleep duration was significantly associated with changes in blood biochemical levels. The results of the logistic regression analysis showed that the levels of multiple biochemical parameters are associated with increased risk of total mortality.

CONCLUSIONS

This is the first large longitudinal study to indicate that sleep duration was associated with changes in multiple biochemical levels in the blood and total mortality.

Whole blood genome-wide gene expression profile in males after prolonged wakefulness and sleep recovery

Although the specific functions of sleep have not been completely elucidated, the literature has suggested that sleep is essential for proper homeostasis. Sleep loss is associated with changes in behavioral, neurochemical, cellular, and metabolic function as well as impaired immune response. Using high-resolution microarrays we evaluated the gene expression profiles of healthy male volunteers who underwent 60 h of prolonged wakefulness (PW) followed by 12 h of sleep recovery (SR). Peripheral whole blood was collected at 8 am in the morning before the initiation of PW (Baseline), after the second night of PW, and one night after SR. We identified over 500 genes that were differentially expressed. Notably, these genes were related to DNA damage and repair and stress response, as well as diverse immune system responses, such as natural killer pathways including killer cell lectin-like receptors family, as well as granzymes and T-cell receptors, which play important roles in host defense. These results support the idea that sleep loss can lead to alterations in molecular processes that result in perturbation of cellular immunity, induction of inflammatory responses, and homeostatic imbalance. Moreover, expression of multiple genes was downregulated following PW and upregulated after SR compared with PW, suggesting an attempt of the body to re-establish internal homeostasis. In silico validation of alterations in the expression of CETN3, DNAJC, and CEACAM genes confirmed previous findings related to the molecular effects of sleep deprivation. Thus, the present findings confirm that the effects of sleep loss are not restricted to the brain and can occur intensely in peripheral tissues.

Electroacupuncture and moxibustion decrease renal sympathetic nerve activity and retard progression of renal disease in rats

BACKGROUND/AIM

Chronic kidney disease (CKD) is an increasing major public health problem worldwide. The sympathetic nervous system and nitric oxide play an important role in the pathogenesis of CKD. Traditional Chinese medicine has accumulated thousands of years of therapeutic experiences. Electroacupuncture (EA) and moxibustion (MO) are two such therapeutic strategies. The aim of this study was to investigate the renal and hemodynamic effects of EA-MO in an experimental model of a CKD.

METHODS

Male Wistar rats submitted to 5/6th nephrectomy (5/6 NX) were studied for 8 weeks. There were four groups: (1) control, normal rats; (2) NX, 5/6 NX only; (3) NX-AS, 5/6 NX and EA-MO session using sham points, and (4) NX-AM, 5/6 NX and EA-MO session using real acupoints. Biochemical and blood pressure studies, renal sympathetic nerve activity measurements, nitric oxide levels and the histopathological indices were assessed.

RESULTS

The EA- and MO-treated group presented significant improvement in all measured functional and histopathological parameters.

CONCLUSION

These findings suggest that EA-MO had beneficial effects on CKD. This effect was probably achieved by the modulation of the renal sympathetic nerve activity and nitric oxide levels, leading to decreased blood pressure, which is associated with less proteinuria.