The day-night differences in cognitive and anxiety-like behaviors of mice after chronic sleep restriction.

Animal behavioral tests are often conducted during the day. However, rodents are nocturnal animals and are primarily active at night. The aim of this study was to determine whether there are diurnal changes in cognitive and anxiety-like performance of mice following chronic sleep restriction (SR). We also investigated whether this phenotypic difference is related to the diurnal variation of glymphatic clearance of metabolic wastes. Mice received 9-day SR by the use of the modified rotating rod method, followed by the open field, elevated plus maze, and Y-maze tests conducted during the day and at night, respectively. Brain ß-amyloid (Aß) and tau protein levels, the polarity of aquaporin4 (AQP4), a functional marker of the glymphatic system, and glymphatic transport ability were also analyzed. SR mice exhibited cognitive impairment and anxiety-like behaviors during the day, but not at night. AQP4 polarity and glymphatic transport ability were higher during the day, with lower Aß1-42 , Aß1-40 , and P-Tau levels in the frontal cortex. These day-night differences were totally disrupted after SR. These results reveal the diurnal changes in behavioral performance after chronic SR, which may be related to circadian control of AQP4-mediated glymphatic clearance of toxic macromolecules from the brain.

Gene Expression Nebulas (GEN): a comprehensive data portal integrating transcriptomic profiles across multiple species at both bulk and single-cell levels.

Transcriptomic profiling is critical to uncovering functional elements from transcriptional and post-transcriptional aspects. Here, we present Gene Expression Nebulas (GEN, https://ngdc.cncb.ac.cn/gen/), an open-access data portal integrating transcriptomic profiles under various biological contexts. GEN features a curated collection of high-quality bulk and single-cell RNA sequencing datasets by using standardized data processing pipelines and a structured curation model. Currently, GEN houses a large number of gene expression profiles from 323 datasets (157 bulk and 166 single-cell), covering 50 500 samples and 15 540 169 cells across 30 species, which are further categorized into six biological contexts. Moreover, GEN integrates a full range of transcriptomic profiles on expression, RNA editing and alternative splicing for 10 bulk datasets, providing opportunities for users to conduct integrative analysis at both transcriptional and post-transcriptional levels. In addition, GEN provides abundant gene annotations based on value-added curation of transcriptomic profiles and delivers online services for data analysis and visualization. Collectively, GEN presents a comprehensive collection of transcriptomic profiles across multiple species, thus serving as a fundamental resource for better understanding genetic regulatory architecture and functional mechanisms from tissues to cells.

Insomnia trajectories predict chronic inflammation over 2 years at the transition to adulthood.

Insomnia in adolescents is an important public health concern, as its impacts on both their current and future physical and mental health has been discussed. However, few longitudinal studies have examined insomnia and chronic inflammation at the transition from adolescence to adulthood. This study aimed to examine the predictive effects of insomnia and insomnia trajectories on inflammation in college students by using a prospective design. Using data from the College Student Behaviour and Health Cohort Study, which was conducted between April 2019 and April 2021, with an interval of 6 months. We investigated the associations between insomnia trajectories from Year 1 to Year 3 and five inflammatory biomarkers (C-reactive protein [CRP], tumour necrosis factor [TNF]-α, interleukin [IL]-6, IL-1ß, IL-10) at Year 3. The association of insomnia symptoms at baseline, Wave 1 or Wave 2 with inflammatory biomarkers at Wave 4 were also assessed. A total of 312 college students (males: 51.6%) aged 16-26 years (mean [SD] 18.82 [1.22] years) were analysed. We identified two insomnia trajectory classes: increasing insomnia (n = 63 [20.2%]) and decreasing insomnia (n = 249 [79.8%]). Generalised linear model analysis revealed that insomnia symptoms at Wave 1 were associated with significantly elevated CRP and TNF-α levels at Wave 4. Increasing insomnia trajectories predicted consistently higher levels of CRP, TNF-α and IL-10. However, after adjusting for potential confounders, these associations were significantly attenuated. Overall, the findings suggest that insomnia symptoms affect chronic inflammation at the transition to adulthood. Our study needs to be replicated in larger cohorts to further explore how inflammation interacts with insomnia to increase the susceptibility to adverse health conditions.

Association between healthy sleep patterns and depressive trajectories among college students: a prospective cohort study.

BACKGROUND: The purpose of this study was to identify different develpment trajectories of depression symptoms during college period, and prospectively investigate the associations healthy sleep patterns with trajectories of depression symptoms among college students from freshman through junior year. METHODS: A total of 999 participants from the College Student Behavior and Health Cohort Study were included between April 2019 and June 2021. Healthy sleep patterns were defined by chronotype, sleep duration, insomnia, snoring, and daytime sleepiness. Latent growth curve model was used to identify trajectories of depression symptoms. Then binary logistic regression was used to examine association of the healthy sleep patterns with these trajectories. RESULTS: In baseline survey, we found that a total of 100 (10.0%) participants had healthy sleep patterns' score equal to 5. Then, we used 5 surveys' data to identify 2 distinct trajectories of depression symptoms during college (decreasing: 82.5%; increasing: 17.5%). The healthy sleep patterns were associated with these trajectories, the better healthy sleep patterns significantly decrease the risk of increasing trajectories of depression symptoms in males (OR: 0.72, 95%CI: 0.54 ~ 0.97, P = 0.031). Moreover, we found out that the healthy sleep patterns of college students can predict the future depressive symptoms in this study (all P < 0.001). CONCLUSION: Our findings indicate that the better healthy sleep patterns may significantly decrease the risk of increasing trajectory of depression symptoms only in male college students. The results speak to a need for college student with depression symptoms to identify and address sleep problems when present, which could prevent or reduce depression detriments in later life.

[Association between changes in physical activity and comorbid symptoms of anxiety and depression in college students].

OBJECTIVE: To describe the prevalence of physical activity and comorbid symptoms of anxiety and depression in college students, and to explore the correlation strength between changes in physical activity and comorbid symptoms of anxiety and depression, so as to provide a reference for promoting college students' mental health. METHODS: From April to May 2019, 1179 freshmen majoring in public health, nursing, chemistry and physical education were randomly sampled from one university in Hefei City, Anhui Province, and Shangrao City, Jiangxi Province, respectively. A baseline questionnaire survey was conducted. A follow-up survey was conducted in May 2021, and a total of 1046 subjects were included, including 647 female and 399 male. The International Physical Activity Questionnaire-Short Form was used to evaluate the physical activity level of college students, and the Patient Health Questionnaire and Generalized Anxiety Disorder Scale were used to evaluate the anxiety and depression symptoms of college students during follow-up. Determining the coexistence of anxiety and depression symptoms in college students as anxiety-depression comorbid symptoms. RESULTS: In the follow-up survey, the detection rate of anxiety and depression comorbid symptoms of college students was 16.9%(n=177), and the detection rates of sufficient, decreased, increased, and insufficient physical activity changes were 72.5%(n=758), 13.8%(n=144), 9.2%(n=96), and 4.6%(n=48), respectively. The result of multiple Logistic regression model showed that, after controlling for confounding factors, compared with those with sustained high level of physical activity, i. e. , adequate physical activity, increased physical activity(OR=1.89, 95%CI 1.10-3.25), decreased physical activity(OR =2.80, 95% CI 1.72-4.57), and insufficient physical activity(OR = 3.66, 95% CI 1.85-7.23) increased the risk of anxiety-depression comorbidity symptoms of college students(P<0.05). However, there was no significant increase in the risk of anxiety or depressive symptoms in those who increased, decreased, or insufficient physical activity compared with those who were sufficient physical activity(P>0.05). CONCLUSION: The level of physical activity and its changes are related to mental health of college students. The continuous low level of physical activity is associated with the increased risk of comorbidity of anxiety and depression in college students.

Interaction between physical activity and outdoor time on allostatic load in Chinese college students.

BACKGROUND: Physical activity (PA) deficiency, outdoor time reduction during college have been associated with higher cumulative physiological burden as measured by allostatic load (AL). Therefore, the present research sought to analyze the independent and interaction effects of PA and outdoor time on AL in college students. METHODS: A cross-sectional survey was conducted in two universities from April to May 2019. Self-assessment questionnaire and International Physical Activity Questionnaire Short Version (IPAQ-SF) were used in the investigation, AL level was assessed according to the results of biochemical examination, blood pressure and human body morphological measurements. Binary Logistic Analysis was used to analyze the relationships between PA, outdoor time and AL. RESULTS: The prevalence of low PA, low outdoor time and high AL were 16.3%, 71.1% and 47.6%, respectively. Low PA (OR=1.83, 95%CI: 1.20~2.78) and low outdoor time (OR=1.90, 95%CI: 1.35~2.67) are independently associated with high AL (P<0.05, for each). Interaction analysis indicated that low PA and low outdoor time were interactively associated with high AL (OR=2.93, 95%CI: 1.73~4.94, P<0.05). CONCLUSIONS: There were the significant independent and interaction effects between PA and outdoor time on AL. In the future, college students' physical education can be arranged reasonably to reduce the health risks.

Near-Infrared Spectral Characteristic Extraction and Qualitative Analysis Method for Complex Multi-Component Mixtures Based on TRPCA-SVM.

Quality identification of multi-component mixtures is essential for production process control. Artificial sensory evaluation is a conventional quality evaluation method of multi-component mixture, which is easily affected by human subjective factors, and its results are inaccurate and unstable. This study developed a near-infrared (NIR) spectral characteristic extraction method based on a three-dimensional analysis space and establishes a high-accuracy qualitative identification model. First, the Norris derivative filtering algorithm was used in the pre-processing of the NIR spectrum to obtain a smooth main absorption peak. Then, the third-order tensor robust principal component analysis (TRPCA) algorithm was used for characteristic extraction, which effectively reduced the dimensionality of the raw NIR spectral data. Finally, on this basis, a qualitative identification model based on support vector machines (SVM) was constructed, and the classification accuracy reached 98.94%. Therefore, it is possible to develop a non-destructive, rapid qualitative detection system based on NIR spectroscopy to mine the subtle differences between classes and to use low-dimensional characteristic wavebands to detect the quality of complex multi-component mixtures. This method can be a key component of automatic quality control in the production of multi-component products.

[Mediating role of IL-10 in the association between health-risk behaviors and depressive symptoms of college students].

OBJECTIVE: To examine the relationship between health-risk behaviors and depressive symptoms among college students, and explore the mediating role of plasma IL-10 level in the relationship between the two. METHODS: Freshman students in two universities in Hefei City, Anhui Province and Shangrao City, Jiangxi Province were recruited between April and May 2019, and follow-up investigation was conducted 6 months later. Health risk behaviors were measured based on the Young Risk Behavior Surveillance System(YRBSS) questionnaire, and depressive symptoms was evaluated by using the Depression Anxiety Stress Scale(DASS-21) among college students at baseline and 6 months follow-up survey. Plasma interleukin-10(IL-10) level was measured at baseline. Univariate analysis was used to compare the correlation between health risk behaviors and depressive symptoms among college students. Binary Logistic regression analyzed the relationship between health risk behaviors, IL-10 and depressive symptoms. The mediation model was used to explore the mediating role of IL-10 levels in the association between health risk behaviors and depressive symptoms. RESULTS: At baseline, boys reported a higher rate of depressive symptoms than that of girls(χ~2=6.33, P=0.01); higher rates of depressive symptoms were observed in students who were from a family with a low perceived economic status(χ~2=7.31, P=0.03)or in poor health(χ~2=6.71, P=0.04). Participants who reported low physical activity(χ~2=19.09, P<0.01), smoking(χ~2=7.03, P<0.01), and poor sleep quality(χ~2=68.78, P<0.01)at baseline were more likely to experience depressive symptoms. Multiple health-risk behaviors at baseline were positively correlated with depressive symptoms among college students. After adjusting gender, self-reported family economy and self-rated health, the regression model showed that plasma IL-10 at baseline was negatively associated with the prevalence of depressive symptoms(OR=0.36, 95% CI 0.18-0.72) and the incidence of depressive symptoms after 6 months(OR=0.20, 95% CI 0.08-0.49). Structural equation model showed that health-risk behaviors was negatively correlated to IL-10 level(ß=-0.13, SE=0.04), IL-10 negatively predicted depressive symptoms at follow-up(ß=-0.09, SE=0.04), and IL-10 play a mediating role between health risk behavior and depressive symptoms. CONCLUSION: Health risk behaviors are positively correlated with depressive symptoms among college students. Plasma IL-10 level at baseline was negatively associated with the incidence of depressive symptoms after 6 months, and IL-10 level at baseline has a partial mediating effect between baseline health risk behavior clustering and depressive symptoms at follow-up.

Quantum-channel capacity of distributing orbital-angular-momentum states for underwater optical quantum communication.

We employ non-diffractive Bessel-Gaussian beams to investigate the effect of oceanic turbulence on quantum communication protocols via behaviors of quantum-channel capacity and trace distance, based on the analytical expression of the phase structure function of an orbital-angular-momentum (OAM) beam in underwater wireless optical communication. Our results show that turbulence conditions with a larger inner-scale and outer-scale factors, higher dissipation rate of kinetic energy, lower dissipation rate of the mean-squared temperature, and smaller temperature-salinity contribution ratio are beneficial to quantum communication performance. Moreover, we show that the distribution protocol may be improved by distributing quantum superposition states instead of OAM eigenstates. We believe our work provides the first theoretical exploration of quantum-channel capacity in underwater OAM quantum communication.

iDog: an integrated resource for domestic dogs and wild canids.

The domestic dog (Canis lupus familiaris) is indisputably one of man's best friends. It is also a fundamental model for many heritable human diseases. Here, we present iDog (http://bigd.big.ac.cn/idog), the first integrated resource dedicated to domestic dogs and wild canids. It incorporates a variety of omics data, including genome sequences assemblies for dhole and wolf, genomic variations extracted from hundreds of dog/wolf whole genomes, phenotype/disease traits curated from dog research communities and public resources, gene expression profiles derived from published RNA-Seq data, gene ontology for functional annotation, homolog gene information for multiple organisms and disease-related literature. Additionally, iDog integrates sequence alignment tools for data analyses and a genome browser for data visualization. iDog will not only benefit the global dog research community, but also provide access to a user-friendly consolidation of dog information to a large number of dog enthusiasts.

GSA-Human: Genome Sequence Archive for Human.

The Genome Sequence Archive for Human (GSA-Human) is a data repository specialized for human genetic related data derived from biomedical researches, and also supports the data collection and management of National Key Research and Development Projects. GSA-Human has a data security management strategy according to the national regulations of human genetic resources. It provides two different models of data access: Open-access and Controlled-access. Open-access data are universally and freely accessible for global researchers, while Controlled-access ensures that data are accessed only by authorized users with the permission of the Data Access Committee (DAC). Till July 2021, GSA-Human has housed more than 5.27 PB of data from 750 datasets.

Autosomal dominant hereditary spastic paraplegia caused by mutation of UBAP1.

Hereditary spastic paraplegias (HSP) are a group of rare neurodegenerative diseases characterized by progressive spastic paraparesis. UBAP1 was recently found to induce a rare type of HSP (SPG80). We identified a family with eight inherited spastic paraplegic patients carrying a novel heterozygous mutation c.279delG (p.S94Vfs*9) of UBAP1. We demonstrated a lack of functional UBAP1 in these patients, resulting in the neurological disorder caused by interceptions of the ESCRT pathway. Extending from the older onset-age identified from this family, we found that comparing with the European and other populations, Asian patients displayed less proportion of severe patients and an older average age at onset. The origins of SPG80 patients associated with both their onset age and their disease severity, while the age at onset was not correlated with the disease severity.

A systematic review and meta-analysis of randomized controlled trials: Skin-patch of Chinese herbal medicine for patients with acute gouty arthritis.

AIMS: To evaluate the evidence of the effectiveness and safety of Chinese herbal medicine skin-patches for patients with acute gouty arthritis. BACKGROUND: Acute gouty arthritis is a problem that can limit the level of activity and impair the quality of life. In China, many clinical studies have demonstrated that skin-patches of Chinese herbal medicines benefit patients with acute gouty arthritis. However, the reported clinical effects vary. DESIGN: A systematic review and meta-analysis of randomized controlled trials. DATA SOURCES: Three English databases including CENTRAL (1993 to February 2017), PubMed (1966 to February 2017) and EMBASE (1974 to February 2017) and four Chinese databases including Chinese National Knowledge Infrastructure, Chinese VIP Information, SinoMed and Wanfang (all, 1949 - February 2017) were searched. Randomized controlled trials that compared skin-patches of Chinese herbal medicine with or without conventional treatments to conventional treatments, no treatment or a placebo treatment for patients with acute gouty arthritis were included. REVIEW METHODS: We conducted a systematic review and meta-analysis following the Cochrane process. Two authors selected the studies, extracted the data and evaluated the risk of bias of the included trials. RESULTS: Nineteen studies met our inclusion criteria. After synthesizing the data, the results showed that skin-patches of CHM combined with Western medicine seemed to be more effective than Western medicine alone for pain relief in patients with acute gouty arthritis and had fewer adverse events. CONCLUSION: Due to the quality of the data, larger and more rigorously designed clinical trials with proper outcome measures are necessary.

WD40-REPEAT 5a functions in drought stress tolerance by regulating nitric oxide accumulation in Arabidopsis.

Nitric oxide (NO) generation by NO synthase (NOS) in guard cells plays a vital role in stomatal closure for adaptive plant response to drought stress. However, the mechanism underlying the regulation of NOS activity in plants is unclear. Here, by screening yeast deletion mutants with decreased NO accumulation and NOS-like activity when subjected to H2 O2 stress, we identified TUP1 as a novel regulator of NOS-like activity in yeast. Arabidopsis WD40-REPEAT 5a (WDR5a), a homolog of yeast TUP1, complemented H2 O2 -induced NO accumulation of a yeast mutant Δtup1, suggesting the conserved role of WDR5a in regulating NO accumulation and NOS-like activity. This note was further confirmed by using an Arabidopsis RNAi line wdr5a-1 and two T-DNA insertion mutants of WDR5a with reduced WDR5a expression, in which both H2 O2 -induced NO accumulation and stomatal closure were repressed. This was because H2 O2 -induced NOS-like activity was inhibited in the mutants compared with that of the wild type. Furthermore, these wdr5a mutants were more sensitive to drought stress as they had reduced stomatal closure and decreased expression of drought-related genes. Together, our results revealed that WDR5a functions as a novel factor to modulate NOS-like activity for changes of NO accumulation and stomatal closure in drought stress tolerance.

CATALASE2 functions for seedling postgerminative growth by scavenging H2 O2 and stimulating ACX2/3 activity in Arabidopsis.

Increased fatty acid ß-oxidation is essential for early postgerminative growth in seedlings, but high levels of H2 O2 produced by ß-oxidation can induce oxidative stress. Whether and how catalase (CAT) functions in fine-tuning H2 O2 homeostasis during seedling growth remain unclear. Here, we report that CAT2 functions in early seedling growth. Compared to the wild type, the cat2-1 mutant, with elevated H2 O2 levels, exhibited reduced root elongation on sucrose (Suc)-free medium, mimicking soils without exogenous sugar supply. Treatment with the H2 O2 scavenger potassium iodide rescued the mutant phenotype of cat2-1. In contrast to the wild type, the cat2-1 mutant was insensitive to the CAT inhibitor 3-amino-1,2,4-triazole in terms of root elongation when grown on Suc-free medium, suggesting that CAT2 modulates early seedling growth by altering H2 O2 accumulation. Furthermore, like cat2-1, the acyl-CoA oxidase (ACX) double mutant acx2-1 acx3-6 showed repressed root elongation, suggesting that CAT2 functions in early seedling growth by regulating ACX activity, as this activity was inhibited in cat2-1. Indeed, decreased ACX activity and short root of cat2-1 seedlings grown on Suc-free medium were rescued by overexpressing ACX3. Together, these findings suggest that CAT2 functions in early seedling growth by scavenging H2 O2 and stimulating ACX2/3 activity.

Association of chronotype, social jetlag, sleep duration and depressive symptoms in Chinese college students.

OBJECTIVES: To describe the prevalence of depressive symptoms among Chinese college students and examine the relationship between sleep and circadian rhythm disruption (SCRD) indicators (chronotype, social jetlag, sleep duration) and depressive symptoms. METHODS: From April to May 2019, the College Student Behavior and Health Cohort Study was conducted among Chinese college students from 2 universities in Anhui and Jiangxi provinces. The current study used data from the third follow-up study. Questionnaire content includes socio-demographic and lifestyle information. Social jetlag and sleep duration were calculated by answering the question about sleep time. Chronotype was assessed by the Morning and Evening Questionnaire (MEQ-5). Depressive symptoms were evaluated by the Patient Health Questionnaire 9 (PHQ-9). A Chi-square test was used to examine the proportion depressive symptoms. Multinomial logistic regression model were used to explore the associations of circadian rhythm indicators with depressive symptoms. RESULTS: The prevalence of mild depression, moderate and above depression was 18.8 % and 6.9 %. Evening types (E-types) and short sleep duration were significantly associated with depression. Stratified analysis indicated that E-types and social jetlag≥2 h were associated with mild depression (OR = 5.67, 95 % CI: 1.83-17.51), as well as stratified analysis indicated that E-types and sleep duration<8 h were associated with mild depression (OR = 5.10, 95 % CI: 1.88-13.87). CONCLUSIONS: The findings suggest that depressive symptoms are more severe when multiple SCRD indicators are out of whack. The intervention programs of depressive symptoms should consider the context of the multidimensional aspects of Chinese college student sleep.

Poor sleep pattern is associated with metabolic disorder during transition from adolescence to adulthood.

Objective: The purpose of this study was to investigate whether sleep pattern is associated with metabolic disorders among young adults. Methods: We measured sleep patterns using multiple sleep behaviors in an ongoing prospective cohort among college students (n = 1,151). At baseline, 729 college students provided fasting blood samples and human body morphological measurements for quantification of metabolic parameters. Then, 340 participants continued to take metabolic parameters measurements at a 2-year follow-up. Sleep patterns were defined by chronotype, sleep duration, insomnia, snoring, and daytime sleepiness. Metabolic scores were derived for four metabolic parameters including body mass index (BMI), waist circumference (WC), fasting blood sugar (FBG), and insulin. Multivariate linear regression model was applied to analyze the association between sleep pattern types and metabolic parameters and metabolic scores. Results: In the baseline survey, we found that a total of 41 (4.1%) participants had poor sleep patterns. Then, metabolic scores were significantly higher among college students with poor sleep patterns, compared with those who with healthy sleep patterns at baseline (1.00 ± 0.96 vs. 0.78 ± 0.72, p < 0.05) and 2-year follow-up (0.34 ± 0.65 vs. 1.50 ± 1.64, p < 0.05). After covariates were adjusted, poor sleep pattern (ß = 0.22, 95% CI: 0.06~2.53, p = 0.001) was associated with elevated metabolic scores at the 2-year follow-up. Conclusions: The elevated metabolic burden observed in college students with poor sleep patterns highlights the need to identify and address sleep problems in order to minimize the long-term impact on disease vulnerability.

Smartphone Use and Inflammation at 2-Year Follow-Up in College Students: The Mediating Role of Physical Activity.

Purpose: Smartphone use could lead to being physically inactive and a greater risk for health problems, such as inflammation. However, the associations between smartphone use, physical activity (PA), and systemic low-grade inflammation remained unclear. This study aimed to examine the potential mediating effect of PA on the association between smartphone use and inflammation. Patients and Methods: A two-year follow-up study was conducted between April 2019 and April 2021. Duration of smartphone use, smartphone dependence and PA were assessed by a self-administered questionnaire. Laboratory analysis of blood samples was performed to evaluate the levels of TNF-α, IL-6, IL-1ß, and CRP as biomarkers of systemic inflammation. The correlations between smartphone use, PA, and inflammation were analyzed using Pearson correlation. Structural equation modelling was used to analyze the potential mediating effect of PA on the associations between smartphone use and inflammation. Results: A total of 210 participants were included with a mean (standard deviation) age of 18.7 (1.0) years, 82 (39%) of whom were males. Smartphone dependence was negatively associated with the total PA level (r=-0.18, P<0.01). PA mediated the associations between the duration of smartphone use and smartphone dependence with inflammatory markers. Specifically, as PA decreased, the duration of smartphone use was more negatively associated with TNF-α (ab=-0.027; 95% CI: -0.052, -0.007) and more positively correlated to IL-6 (ab=0.020; 95% CI: 0.001, 0.046) and CRP (ab=0.038; 95% CI: 0.004, 0.086); smartphone dependency was more negatively associated with TNF-α (ab=-0.139; 95% CI: -0.288, -0.017) and more positively related to CRP (ab=0.206; 95% CI: 0.020, 0.421). Conclusion: Our study illustrates that there are no direct associations between smartphone use and systemic low-grade inflammation, however, PA level plays a weak but significant mediating effect on the associations between smartphone use and inflammation among college students.

Depressive symptoms predict longitudinal changes of chronic inflammation at the transition to adulthood.

Background: Inflammation is closely related to poor mental and physical health, including depressive symptoms and its specific symptoms. To reveal the linear and nonlinear relationships between depressive symptoms and chronic inflammation levels, and perform further analysis of the associations between symptom-specificity of depressive symptoms and inflammation among young adults by using a prospective design. Methods: In this longitudinal study, we examined college students recruited from two universities in China, who were examined at baseline and 2-years follow-up. Depressive symptoms were measured by applying the Patient Health Questionnaire 9 (PHQ-9) at baseline. Plasma levels of four inflammatory biomarkers, including interleukin-6 (IL-6), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and C reactive protein (CRP) were assayed at baseline and 2-year follow-up. In addition to the conventional generalized linear models, as well as restricted cubic splines were innovatively used to analyze the cross-sectional and longitudinal nonlinear relationships between depressive symptoms and inflammatory biomarkers. Results: Generalized linear model analysis revealed that there were no statistical associations between depressive symptoms and any inflammatory biomarker levels. The results of the restricted cubic spline demonstrated a U-shaped nonlinear association between depressive symptoms and ΔIL-1ß or ΔTNF-α (changes in baseline and 2-year follow-up), but these associations disappeared after adjusting the confounders. Symptom-specificity of depressive symptoms such as sleeping problems and suicidal ideation were associated with lower IL-1ß at baseline or changes in IL-1ß levels. Sleeping problems and psychomotor changes at baseline were associated with higher CRP at 2-year follow-up. Suicidal ideation at baseline was associated with changes in TNF-α levels. Conclusion: Our findings suggested that symptom-specificity of depressive symptoms was associated with inflammation during a 2-year follow-up at the transition to adulthood. Simultaneously, more research is warranted to seek the directionality of depressive symptoms and chronic inflammation.