Hydrokinetic pancreatic function and insulin secretion are moduled by Cl- uniporter Slc26a9 in mice

AIM

Slc26a9 is a member of the Slc26 multifunctional anion transporter family. Polymorphisms in Slc26a9 are associated with an increased incidence of meconium ileus and diabetes in cystic fibrosis patients. We investigated the expression of Slc26a9 in the murine pancreatic ducts, islets and parenchyma, and elucidated its role in pancreatic ductal electrolyte and fluid secretion and endocrine function.

METHODS

Pancreatic Slc26a9 and CFTR mRNA expression, fluid and bicarbonate secretion were assessed in slc26a9^-/- mice and their age- and sex-matched wild-type (wt) littermates. Glucose and insulin tolerance tests were performed.

RESULTS

Compared with stomach, the mRNA expression of Slc26a9 was low in pancreatic parenchyma, 20-fold higher in microdissected pancreatic ducts than parenchyma, and very low in islets. CFTR mRNA was ~10 fold higher than Slc26a9 mRNA expression in each pancreatic cell type. Significantly reduced pancreatic fluid secretory rates and impaired glucose tolerance were observed in female slc26a9^-/- mice, whereas alterations in male mice did not reach statistical significance. No significant difference was observed in peripheral insulin resistance in slc26a9^-/- compared to sex- and aged-matched wt controls. In contrast, isolated slc26a9^-/- islets in short term culture displayed no difference in insulin content, but a significantly reduced glucose-stimulated insulin secretion compared to age- and sex-matched wt islets, suggesting that the impaired glucose tolerance in the absence of Slc26a9 expression these is a pancreatic defect.

CONCLUSIONS

Deletion of Slc26a9 is associated with a reduction in pancreatic fluid secretion and impaired glucose tolerance in female mice. The results underline the importance of Slc26a9 in pancreatic physiology.

[RIP1/RIP3-MLKL signaling pathway correlates with occurrence, progression and prognosis of chronic heart failure]

OBJECTIVE

To detect plasma levels of receptor-interacting protein kinase 1 (RIP1), RIP3 and mixed lineage kinase domain-like protein (MLKL) in patients with chronic heart failure and explore the expression pattern of programmed necrosis signaling pathway RIP1/RIP3-MLKL in the progression of heart failure.

METHODS

The patients with chronic heart failure (NYHA class Ⅱ-Ⅳ) admitted in our hospital between February, 2020 and March, 2021 were prospectively enrolled in this study, with 21 healthy volunteers as the control group. The enrolled patients included 20 with grade Ⅱ, 33 with grade Ⅲ, and 43 with grade Ⅳ cardiac function. Fasting venous blood was collected from all the participants for detecting plasma levels of RIP1, RIP3, and MLKL and protein expressions of RIP1/RIP3-MLKL pathway using enzyme-linked immunosorbent assay (ELISA) and Western blotting. The patients with grade Ⅳ cardiac function were followed up for 5 months to evaluate the clinical prognostic indicators.

RESULTS

Compared with the healthy volunteers, the patients with grade Ⅱ, Ⅲ and Ⅳ cardiac function had significantly increased plasma levels of RIP1, RIP3, and MLKL (P < 0.01), and their levels were significantly higher in grade Ⅲ/Ⅳ patients than in those with grade Ⅱ cardiac function (P < 0.01); the plasma levels of RIP1 and MLKL were significantly higher in grade Ⅳ patients than in grade Ⅲ patients (P < 0.05). The results of Western blotting also showed increased expressions of the proteins in the RIP1/RIP3-MLKL pathway in patients with heart failure. Pearson correlation analysis suggested that in patients with heart failure, the expression levels of RIP1, RIP3, and MLKL were positively correlated with SCR, AST, LVEDD and NT-proBNP (P < 0.05). Follow-up study of the patients with grade Ⅳ cardiac function showed that higher expression levels of RIP1/RIP3-MLKL were associated with a poorer prognosis of the patients.

CONCLUSION

The expressions of RIP1, RIP3 and MLKL are significantly upregulated in patients with heart failure in positive correlation with the severity of the disease condition, and the activation of the RIP1/RIP3-MLKL signaling pathway may contribute to the occurrence, development and prognosis of chronic heart failure.

Plasma Metabolomic Profiles in Recovered COVID-19 Patients without Previous Underlying Diseases 3 Months After Discharge

BACKGROUND

It remains unclear whether discharged COVID-19 patients have fully recovered from severe complications, including the differences in the post-infection metabolomic profiles of patients with different disease severities.

METHODS

COVID-19-recovered patients, who had no previous underlying diseases and were discharged from Wuhan Union Hospital for 3 months, and matched healthy controls (HCs) were recruited in this prospective cohort study. We examined the blood biochemical indicators, cytokines, lung computed tomography scans, including 39 HCs, 18 recovered asymptomatic (RAs), 34 recovered moderate (RMs), and 44 recovered severe/ critical patients (RCs). A liquid chromatography-mass spectrometry-based metabolomics approach was employed to profile the global metabolites of fasting plasma of these participants.

RESULTS

Clinical data and metabolomic profiles suggested that RAs recovered well, but some clinical indicators and plasma metabolites in RMs and RCs were still abnormal as compared with HCs, such as decreased taurine, succinic acid, hippuric acid, some indoles, and lipid species. The disturbed metabolic pathway mainly involved the tricarboxylic cycle, purine, and glycerophospholipid metabolism. Moreover, metabolite alterations differ between RMs and RCs when compared with HCs. Correlation analysis revealed that many differential metabolites were closely associated with inflammation and the renal, pulmonary, heart, hepatic, and coagulation system functions.

CONCLUSION

We uncovered metabolite clusters pathologically relevant to the recovery state in discharged COVID-19 patients which may provide new insights into the pathogenesis of potential organ damage in recovered patients.

[Exploring the therapeutic mechanism of quercetin for heart failure based on network pharmacology and molecular docking]

OBJECTIVE

To investigate the molecular mechanism of quercetin in the treatment of heart failure (HF) based on network pharmacology and molecular docking.

METHODS

Quercetin and HF-related targets were obtained using TCMSP, PharmMapper, CTD and GeneCards databases, and quercetin-HF intersection targets were obtained through the online website Venn; the protein interaction network was constructed and imported into Cytoscape 3.7.2 to identify the core targets of quercetin in the treatment of HF.GO and KEGG pathway enrichment analyses were performed using R package, and molecular docking was performed using Auto Dock Vina.The protein levels of AKT1, phospho-AKT(Ser473), eNOS, MMP9, and caspase-3 in quercetin-treated HF cell models were detected using protein immunoblotting.

RESULTS

We identified 80 quercetin-HF intersectional targets (AKT1, CASP3, MAPK1, MMP9, and MAPK8) and 5 core targets of quercetin for treatment of HF.GO analysis suggested that the therapeutic effect of quercetin for HF was mediated mainly by such biological processes as responses to peptide hormones, phosphatidylinositol-mediated signalling, responses to lipopolysaccharides, responses to molecules of bacterial origin and regulation of inflammatory responses.KEGG pathway enrichment analysis identified lipid and atherosclerosis pathway, proteoglycans in cancer, PI3K-AKT signaling pathway, diabetic cardiomyopathy and MAPK signaling pathway as the most significantly enriched signaling pathways.Molecular docking showed a good binding activity of quercetin to the 5 core targets.The results of protein immunoblotting showed that 100 μmol/L quercetin significantly reduced AKT1, phospho-AKT (Ser473), eNOS, MMP9 and caspase-3 levels in the cell models of HF (P < 0.01).

CONCLUSION

Quercetin improves the pathological changes in HF possibly by regulating the AKT1-eNOS-MMP9 pathway to inhibit cell apoptosis.

Circ_0001971 regulates oral squamous cell carcinoma progression and chemosensitivity by targeting miR-194/miR-204 in vitro and in vivo

OBJECTIVE

Circular RNAs (circRNAs) play a wide role in human cancers, including oral squamous cell carcinoma (OSCC). The purpose of this study was to investigate the biological functions of circ_0001971 and associated mechanisms in OSCC.

MATERIALS AND METHODS

The expression of circ_0001971, miR-194, and miR-204 was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Cell proliferation and viability were assessed using cell counting kit-8 (CCK-8) assay. Cell migration and invasion were examined using the transwell assay. Cell apoptosis was monitored by flow cytometry assay. The protein levels of proliferation marker (CyclinD1), epithelial mesenchymal-transition (EMT) markers (E-cadherin (E-cad) and N-cadherin (N-cad)) and apoptosis markers (Cleaved-caspase-3 (Cleaved-cas-3) and Cleaved-caspase-9 (Cleaved-cas-9)) were measured by Western blot. The relationship between circ_0001971 and miR-194 or miR-204 was predicted by online tool starBase and verified by the Dual-Luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Tumor formation assay in nude mice was conducted to observe the role of circ_0001971 in vivo.

RESULTS

The expression of circ_0001971 was significantly increased in tumor tissues and cell lines. Circ_0001971 knockdown inhibited cell proliferation, migration, and invasion but promoted cisplatin (DDP) sensitivity and cell apoptosis. It was confirmed that miR-194 and miR-204 were targets of circ_0001971, and miR-194 inhibition or miR-204 inhibition reversed the effects of circ_0001971 knockdown in OSCC cells. Moreover, circ_0001971 knockdown impeded tumorigenesis and development in vivo.

CONCLUSIONS

Circ_0001971 regulates cell proliferation, migration, invasion, apoptosis, and chemosensitivity of OSCC by interacting with miR-194 and miR-204 in vitro and in vivo. We provided a theoretical basis for the action mechanism of circ_0001971 on OSCC progression and chemosensitivity.

[Effect of piRNA NU13 in regulating biological behaviors of human Wilms tumor cells in vitro]

OBJECTIVE

To investigate the role of the differential piRNA NU13 derived from piwil2-induced cancer stem-like cells (piwil2-iCSCs) in regulating biological behaviors of Wilms tumor cells (G401).

OBJECTIVE

The expressions of piRNA NU13 and NOP56 were detected in Wilms tumor cell line G401 using RT-qPCR. G401 cells were transfected with piRNA NU13 mimics and inhibitor for its over-expression and inhibition, and the transfection efficiency was verified with RT-qPCR. The changes in proliferation of G401 cells after transfection were detected using CCK8 assay, and cell apoptosis was analyzed using flow cytometry. Wound healing assay and Transwell assay were performed to examine the changes in migration and invasion abilities of the transfected cells. The binding of NOP56 and piRNA NU13 was detected using dual luciferase experiment. The protein expressions of MMP2, MMP9, BAX, Bcl2, and NOP56 in the cells were detected with Western blotting.

OBJECTIVE

RTqPCR showed that the expression of piRNA NU13 decreased significantly in human Wilms tumor G401 cells as compared with that in renal tubular epithelial cell line HK2 (P < 0.05), and NOP56 was highly expressed in G401 cells and Wilms tumor tissues (P < 0.05). Over-expression of piRNA NU13 significantly suppressed the proliferation, migration and invasion of G401 cells, promoted cell apoptosis (P < 0.05), inhibited the expression of MMP2, MMP9 and Bcl2, and enhanced the expression of BAX (P < 0.05). The results of dual luciferase experiment showed that piRNA NU13 did not bind to NOP56 directly but regulated the expression of NOP56 in an indirect manner.

OBJECTIVE

piRNA NU13 is down-regulated and NOP56 is highly expressed in Wilms tumor. piNU13 may regulate the expression of NOP56 indirectly to inhibit the proliferation, migration and invasion and promote apoptosis of Wilms tumor cells in vitro.

Predictive Value of Serum Creatinine/Cystatin C in Acute Ischemic Stroke Patients under Nutritional Intervention

BACKGROUND AND PURPOSE

As a very common risk of adverse outcomes of the ischemic stroke patients, sarcopenia is associated with infectious complications and higher mortality. The goal of this retrospective study is to explore the predictive value of serum Cr/CysC ratio in acute ischemic stroke patients receiving nutritional intervention.

METHODS

We reviewed adult patients with AIS from December 2019 to February 2020. Patients with acute kidney injury were excluded and all patients received nutritional intervention during a 3-month follow-up period. We collected baseline data at admission including creatinine and cystatin C. The primary poor outcome was major disability (modified Rankin Scale score ≥ 4) at 3 months after AIS.

RESULTS

A total of 217 patients with AIS were identified for this study. Serum Cr/CysC ratio was significantly correlated with NIHSS at discharge, 1-month modified Rankin Scale score, and 3-month modified Rankin Scale score. During 3 months, 34 (15.70%) patients had a poor outcome after AIS and 11 (5.10%) patients died within 30 days. In multivariable logistic regression analyses, serum Cr/CysC ratio at admission was independently associated with 3-month poor outcomes (OR: 0.953, 95% CI: 0.921-0.986, p = .006) and 30-day mortality (OR: 0.953, 95% CI: 0.921-0.986, p = .006).

CONCLUSION

As a blood biochemical indexes reflecting the muscle mass and aiding in risk stratification, Cr/CysC ratio at admission could be used as a predictor of 30-day mortality and long-term poor prognosis in AIS patients.

Comparison of clinical characteristics among younger and elderly deceased patients with COVID-19: a retrospective study

We aimed to compare the age-related clinical characteristics between younger and elderly deceased COVID-19 patients. This single-center retrospective study included 163 adult deceased COVID-19 patients who were admitted to Wuhan Union Hospital West Campus from January 12, 2020, to March 30, 2020. Demographic and clinical features were collected by reviewing the medical records. The median age of the 163 deceased patients was 69 (interquartile range [IQR], 62-78) years. They were classified as younger (age 18-69 years; 86/163, 52.8%) and elderly (≥70 years; 77/163, 47.2%) subjects. Younger deceased patients were more likely to develop fever (72/86 vs 54/77, P=0.039) than elderly deceased patients were while anorexia was (29/77 vs 19/86, P=0.029) more common in elderly deceased patients than in younger deceased patients. In multivariate analyses, age was a protective factor for acute cardiac injury of deceased COVID-19 patients (odds ratio [OR] 0.968, [95% confidence interval (CI), 0.940-0.997]; P=0.033) while chronic cardiac disease was a risk factor for acute cardiac injury of deceased COVID-19 patients (OR 2.660 [95%CI, 1.034-6.843]; P=0.042). Our study described the clinical characteristics of younger and elderly deceased COVID-19 patients and demonstrated that younger deceased patients were more likely to develop an acute cardiac injury.

MiR-491 suppresses migration and invasion via directly targeting TPX2 in breast cancer

OBJECTIVE

Breast cancer (BC) is one of the primary causes of tumor-related female mortalities. Although in recent years, we have made great progress in the systemic therapy and earlier diagnosis for BC patients, recurrence or distant metastasis remains leading obstacles for the successful therapy of BC. Therefore, a comprehensive understanding of the molecular mechanism underlying the progression may be crucial in developing an effective strategy against BC. The current research aimed to explore the expressions, functions and molecular mechanism of microRNA-491 (miR-491) in BC.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to examine the level of miR-491 expression in 52 pairs of BC tissues and para-cancerous specimens, and the relation between miR-491 level and the clinical features of BC patient prognosis was analyzed. Transwell invasion and migration assays were conducted to determine whether miR-491 had effects on the regulation of BC metastasis. Potential target genes of miR-491 were found out using TargetScan to explore the molecular functions of miR-491 in inhibiting breast cancer cell invasion and migration. To elucidate the mechanism of TPX2 in suppressing cell invasion and migration medicated by miR-491in breast cancer, we further transfected TPX2 siRNAs into MCF-7 cells to delete endogenous TPX2, along with the transfections with miR-491 inhibitor into MCF-7 cell lines.

RESULTS

The findings demonstrated that miR-491 expressions were significantly decreased in BC tissues and cells. The miR-491 restoration suppressed the invasion and migration of BC cells. In addition, we identified the targeting protein for Xklp2 (TPX2) as a direct target of miR-491 in BC. The knockdown of TPX2 markedly reversed miR-491-medicated inhibition of cell invasion and migration in BC cell lines.

CONCLUSIONS

In short, all the results suggested that miR-491 functioned as a tumor suppressor by targeting TPX2 in BC and the miR-491 restoration may be an effective therapy for the BC treatment in the future.

Super-factors associated with transmission of occupational COVID-19 infection among healthcare staff in Wuhan, China

BACKGROUND

Globally, there have been many cases of coronavirus disease 2019 (COVID-19) among medical staff; however, the main factors associated with the infection are not well understood.

AIM

To identify the super-factors causing COVID-19 infection in medical staff in China.

METHODS

A cross-sectional study was conducted between January 1st and February 30th, 2020, in which front-line members of medical staff who took part in the care and treatment of patients with COVID-19 were enrolled. Epidemiological and demographic data between infected and uninfected groups were collected and compared. Social network analysis (SNA) was used to establish socio-metric social links between influencing factors.

FINDINGS

A total of 92 medical staff were enrolled. In all participant groups, the super-factor identified by the network was wearing a medical protective mask or surgical mask correctly (degree: 572; closeness: 25; betweenness centrality: 3.23). Touching the cheek, nose, and mouth while working was the super-factor in the infected group. This was the biggest node in the network and had the strongest influence (degree: 370; closeness: 29; betweenness centrality: 0.37). Self-protection score was the super-factor in the uninfected group but was the isolated factor in the infected group (degree: 201; closeness: 28; betweenness centrality: 5.64). For family members, the exposure history to Huanan Seafood Wholesale Market and the contact history to wild animals were two isolated nodes.

CONCLUSION

High self-protection score was the main factor that prevented medical staff from contracting COVID-19 infection. The main factor contributing to COVID-19 infections among medical staff was touching the cheek, nose, and mouth while working.

[Expression, purification and polyclonal antibody preparation of the Schistosoma japonicum SjGrpE protein]

OBJECTIVE

To investigate the biological properties of Schistosoma japonicum SjGrpE protein, and to express and purify the recombinant SjGrpE protein and test its immunogenicity.

METHODS

The amino acid composition, molecular weight, hydrophilicity and hydrophobicity, transmembrane region, signal peptide, localization, phosphorylation site, ubiquitination site, glycosylation site, secondary and tertiary structures and B cell epitopes of the SjGrpE protein were predicted using bioinformatics analyses. The SjGrpE gene was amplified using PCR assay using S. japonicum cDNA as a template, double enzyme-digested and linked to the pET28a vector to yield the recombinant plasmid pET28a-SjGrpE. The recombinant plasmid pET28a-SjGrpE was transformed into Escherichia coli BL21, and then IPTG was employed to induce the expression of the target protein, which was purified by nickel ion affinity chromatography. After mice were immunized with the recombinant SjGrpE protein, mouse sera were collected, and the polyclonal antibody against the SjGrpE protein was characterized.

RESULTS

SjGrpE protein, which was identified as a hydrophilic protein, was predicted to have a molecular weight of approximately 24.3 kDa without transmembrane regions or signal peptides, and locate in the mitochondrion. SjGrpE protein contained 18 phosphorylation sites and 2 ubiquitination sites, but had no glycosylation sites. In addition, SjGrpE protein contained 5 B-cell epitopes. The full length of SjGrpE gene was approximately 660 bp. The recombinant pET28a-SjGrpE plasmid was successfully generated, and the recombinant SjGrpE protein was obtained following the affinity chromatography, which stimulated mice to secrete high-titer antibodies.

CONCLUSIONS

The recombinant SjGrpE protein has been successfully prepared and this recombinant protein has a high immunogenicity, which provides a basis for evaluating its value as a vaccine candidate for S. japonicum infections.

Development and validation of a risk factor-based system to predict short-term survival in adult hospitalized patients with COVID-19: a multicenter, retrospective, cohort study

BACKGROUND

Coronavirus disease 2019 (COVID-19) has become a public health emergency of global concern. We aimed to explore the risk factors of 14-day and 28-day mortality and develop a model for predicting 14-day and 28-day survival probability among adult hospitalized patients with COVID-19.

METHODS

In this multicenter, retrospective, cohort study, we examined 828 hospitalized patients with confirmed COVID-19 hospitalized in Wuhan Union Hospital and Central Hospital of Wuhan between January 12 and February 9, 2020. Among the 828 patients, 516 and 186 consecutive patients admitted in Wuhan Union Hospital were enrolled in the training cohort and the validation cohort, respectively. A total of 126 patients hospitalized in Central Hospital of Wuhan were enrolled in a second external validation cohort. Demographic, clinical, radiographic, and laboratory measures; treatment; proximate causes of death; and 14-day and 28-day mortality are described. Patients' data were collected by reviewing the medical records, and their 14-day and 28-day outcomes were followed up.

RESULTS

Of the 828 patients, 146 deaths were recorded until May 18, 2020. In the training set, multivariate Cox regression indicated that older age, lactate dehydrogenase level over 360 U/L, neutrophil-to-lymphocyte ratio higher than 8.0, and direct bilirubin higher than 5.0 μmol/L were independent predictors of 28-day mortality. Nomogram scoring systems for predicting the 14-day and 28-day survival probability of patients with COVID-19 were developed and exhibited strong discrimination and calibration power in the two external validation cohorts (C-index, 0.878 and 0.839).

CONCLUSION

Older age, high lactate dehydrogenase level, evaluated neutrophil-to-lymphocyte ratio, and high direct bilirubin level were independent predictors of 28-day mortality in adult hospitalized patients with confirmed COVID-19. The nomogram system based on the four factors revealed good discrimination and calibration, suggesting good clinical utility.

0836 Self-Reported Difficulty Initiating Sleep and Early Morning Awakenings are Associated With Nocturnal Diastolic Non-Dipping in Older Men

Introduction

Aging increases the risk of insomnia and elevated blood pressure (BP). Here, we examined in older men whether reports of difficulty falling asleep (DIS) and early morning awakenings (EMA) are associated with 24-h BP and heart rate.

Methods

We utilized variables from 995 men (mean age: 71 years) who participated in the Uppsala Longitudinal Study of Adult Men (ULSAM). BP and heart rate were measured over 24 hours.

Results

Non-dippers (night-to-day BP ratio &gt; 0.90) had a higher risk of hypertension than dippers (systolic non-dippers vs. systolic dippers, OR [95%CI]: 1.64 [1.21, 2.21], P=0.001; diastolic non-dippers vs. diastolic dippers, 1.50 [1.10, 2.04], P=0.01). Compared to men without DIS, men who reported DIS (10% of the cohort) had a higher risk of diastolic non-dipping (1.85 [1.19, 2.87], P=0.006). Similarly, men who reported EMA (19% of the cohort) had a higher risk of diastolic non-dipping than those without EMA (1.59 [1.12, 2.24], P=0.009). Despite a slightly higher nocturnal diastolic BP among men with EMA vs. those without EMA (+1.4 mmHg, P=0.035), no other differences in BP and heart rate were found between men with and those without insomnia complaints.

Conclusion

Our findings uncover a link between disruption in nocturnal dipping of diastolic BP and insomnia symptoms related to difficulty initiating sleep and early morning awakening in older men.

Support

Authors’ work is funded by the Novo Nordisk Foundation (C.B., NNF19OC0056777), Swedish Brain Research Foundation (C.B., FO2019-0028), Swedish Research Council (C.B., 2015-03100), Åke Wiberg Foundation (X.T., M18-0169, M19-0266), Fredrik and Ingrid Thuring Foundation (X.T., 2018-00365), and the Swedish Medical Research Society (X.T., P18-0084).

0411 Association Between Healthy Dietary Patterns and Self-Reported Sleep Disturbances in Older Men

Introduction

Ageing is often accompanied by an increased prevalence of sleep problems. Healthy lifestyle choices, including diet, are especially important to mitigate such impairments. To date, little is known about how dietary patterns may link to measures of sleep quality in older subjects. Therefore, we investigated in a Swedish older male population, whether adherence to the Mediterranean Diet (MD) or the Healthy Diet Indicator (HDI; based on recommendations from the World Health Organization) is linked to a decrease in sleep disturbances.

Methods

We studied 970 men (age: 71 ± 1yr) from the ULSAM dataset. Sleep initiation or maintenance problems were evaluated by self-reporting questionnaires. Dietary intake was recorded with a pre-coded seven-day food diary. To calculate the adherence scores, intake of dietary components was assessed. Traditional MD components included fat quality, vegetables, fruits, cereals, fish, meat, dairy, and alcohol. The HDI components included saturated-, polyunsaturated fatty acids, proteins, carbohydrates, sucrose, fiber, fruits and vegetables, cholesterol, and fish. Reasonable dietary reporting was calculated to identify possible under- or over-reporters.

Results

When adjusted for potential confounders, no associations between dietary scores and sleep parameters were found. In contrast, low consumption of dairy products —one of the dietary features of the MD —was associated with better subjective sleep initiation. This association was, however, not found in men with adequate reports of daily energy intake (~54% of the cohort).

Conclusion

Our findings do not suggest that older men can mitigate perceived sleep problems by adhering to the MD or HDI. Whether low consumption of dairy products can facilitate sleep initiation must be confirmed in future studies by utilizing objective measures of sleep, such as polysomnography. Finally, when investigating associations between dietary patterns and sleep, particular attention should be paid to the potential confounder of inadequate reporting of energy intake.

Support

This research was funded by Novo Nordisk Foundation (NNF14OC0009349), Swedish Brain Foundation, Swedish Research Council (2015-03100), Åke Wiberg Foundation (M17-0088), Fredrik and Ingrid Thuring Foundation (2017-00313) and the Swedish Medical Research Society.