Research News

Significance: “Exposure to brighter nights and darker days causes circadian disruption, which accompanies poor health outcomes that increase mortality risk. Whether personal day and night light exposure predicts mortality risk is not known. This study captured ~13 million hours of data from light sensors worn by ~89,000 individuals who were over 40 y of age. Those with brighter nights and darker days had higher risk of premature mortality, after accounting for sociodemographic and lifestyle factors. Avoiding night light and seeking day light may promote optimal health and longevity, and this recommendation is both accessible and cost-effective.”

Windred DP, Burns AC, Lane JM, Olivier P, Rutter MK, Saxena R, Phillips AJK, Cain SW. Brighter nights and darker days predict higher mortality risk: A prospective analysis of personal light exposure in >88,000 individuals. Proc Natl Acad Sci U S A. 2024 Oct 22;121(43):e2405924121. doi: 10.1073/pnas.2405924121. Epub 2024 Oct 15. PMID: 39405349.

https://www.pnas.org/doi/10.1073/pnas.2405924121

Abstract:   Suicidal ideation (SI) is a significant precursor and risk marker for suicide behaviors in major depressive disorder (MDD). Exploration of SI trajectory from a longitudinal framework are essential for treatment guidelines and clinical management of suicide risk. This study sought to explore SI trajectories and its associated clinical, sociodemographic characteristics, and initial treatment among patients with MDD. We used data from a non-interventional, national multi-centered prospective cohort study. 1 461 patients with MDD were included in the growth mixture modeling using SI at baseline, 2 weeks, 4 weeks, 8 weeks, 12 weeks, and 6 months, 9 months, and 12 months as the indicator. A multinomial regression was employed with SI trajectory as the outcome and anhedonia, depressive symptoms, atypical depressive symptoms, pharmacological treatments, and other covariates as the predictors. Four distinct SI trajectories were identified: a consistently low SI trajectory(50.7%), a persistently mild SI trajectory(20.6%), a fast declined SI trajectory(8.9%), and a slowly declined trajectory(19.8%). Compared to those with a consistently low SI trajectory, a higher score of anhedonia was associated with an increased risk of experiencing persistently mild (RRR = 1.20, 95%CI: 1.05, 1.38) and slowly declined SI (1.54, 95%CI: 1.32, 1.80). Severity of depressive symptom was also positively associated with the risk of experiencing persistently mild (1.15, 95%CI: 1.13, 1.18) and slowly declined SI (1.17, 95%CI: 1.14, 1.21). And the risk of experiencing slowly declined SI was higher for those use SSRI(1.49, 95%CI: 1.02, 2.31), and for those use antidepressant and antipsychotic/mood stabilizer combined therapy (3.78, 95%CI: 1.48, 9.61). The findings of this study are potentially useful for clinical practice as critical indicators of profiles and interventions for prognosis among patients with MDD. Further research is warranted to explore potential modifiable factors and the association between SI trajectories and suicide behavior.

Ding R, Zhu X, Feng L, Xiao L, Zhang L, He P, Wang G. Trajectories and predictors of suicidal ideation in clinical characteristics and pharmacological treatments for major depressive disorder: a study based on a national multi-centered prospective cohort. Transl Psychiatry. 2024 Oct 6;14(1):422. doi: 10.1038/s41398-024-03115-3. PMID: 39370452; PMCID: PMC11456589.

https://pubmed.ncbi.nlm.nih.gov/39370452/

Abstract: 

Objective: Although Kawasaki disease (KD) is commonly regarded as a single disease entity, clinical subgroups have recently been described. We aimed to validate previous research on clinical subgroups and establish a KD subgroup differentiation model specific to China.

Methods: We analysed clinical data of 1682 patients diagnosed with KD at the Kunming Children’s Hospital from December 2014 to December 2022. We performed principal component analysis and hierarchical clustering on 13 continuous variables. Then, we grouped the patients based on the optimal number of clusters and analysed the clinical characteristics of each subgroup.

Results: We ultimately identified three subgroups. In cluster 1, younger patients predominantly exhibited the highest risk of coronary artery aneurysm and the lowest rate of intravenous immunoglobulin resistance. Cluster 2 was characterised by high inflammatory markers and a lowered risk of coronary artery aneurysm. Cluster 3 was characterised by liver involvement, with significant elevations in liver enzymes, gamma-glutamyl transferase and total bilirubin. We found a positive correlation between the ratio of the rising trend and intravenous immunoglobulin resistance. Cluster 1 and cluster 3 shared similarities with the previously identified younger age subgroup and liver subgroup, respectively, whereas cluster 2 was unique to our study.

Conclusions: Our study preliminarily validated a previous KD subgroup study and established a KD subgroup model in China.

Gong C, Liu K, Li B, Li Y, Gao H, Wang Z, Fu Y, Gao L, Hu L, Wang Y, Wang M, Zhao B, Liu X. Analysis and validation of clinical subgroups of Kawasaki disease in children in China: a retrospective study. BMJ Paediatr Open. 2024 Oct 15;8(1):e002650. doi: 10.1136/bmjpo-2024-002650. PMID: 39414342; PMCID: PMC11481108.

https://pubmed.ncbi.nlm.nih.gov/39414342/

Abstract:

Introduction: Kawasaki disease (KD), a common cause of acquired heart disease in children in developed countries, is primarily treated with intravenous immunoglobulin (IVIG), but some children demonstrate IVIG resistance with increased coronary artery injury risk. T cells have been demonstrated to be involved in the pathogenesis of KD and its treatment with IVIG. However, the role and mechanism of dual TCR T lymphocytes in the occurrence of KD and IVIG therapy remain unclear.

Methods: This study, based on scRNA-seq combined with TCR-seq technology, clustered the peripheral blood mononuclear cells of 3 healthy controls and 6 KD patients before and after IVIG treatment. Comparative analysis was conducted to investigate the differences in the proportion of single/dual receptor T cells, the characteristics of CDR3 repertoires, cell types, and the expression of transcription factors among the three groups. The study aimed to explore the correlation between dual TCR T cells and KD as well as IVIG treatment.

Results: In our experimental results, we observed the presence of dual TCR T cells in all three groups. However, compared to the healthy control group and the IVIG-treated group, the KD patients before IVIG treatment exhibited a lower proportion of dual TCR T cells, with variability between samples, ranging from 4% to 15%. Notably, after IVIG treatment, the proportion of dual TCR T cells significantly increased, stabilizing above 12%, and these T cells also exhibited clonal expansion and a preference for V gene usage. In addition we found differences in dual TCR T cell subsets among the three groups, for example, IVIG treatment increases the proportion of dual TCR Treg cells, but it still remains below that of healthy control groups, significantly higher proportions of both dual TCR CD8 central and effector memory T cells in IVIG-treated KD patients, and differences in the expression of transcription factors between single and dual TCR T cells. These results suggest dual TCR T cells correlate with KD and IVIG treatment.

Conclusion: Dual TCR T lymphocytes, especially dual TCR CD8 T cells and Treg cells, play crucial roles in the pathogenesis of KD and during IVIG treatment, providing strong support for further elucidating KD pathogenesis and optimizing treatment strategies.

Xu Y, Yuan Y, Mou L, Hui L, Zhang X, Yao X, Li J. scRNA+TCR-seq reveals the pivotal role of dual receptor T lymphocytes in the pathogenesis of Kawasaki disease and during IVIG treatment. Front Immunol. 2024 Oct 3;15:1457687. doi: 10.3389/fimmu.2024.1457687. PMID: 39421738; PMCID: PMC11484261.

https://pubmed.ncbi.nlm.nih.gov/39421738/

Abstract: “Exercise enhances synaptic plasticity and alleviates depression symptoms, but the mechanism through which exercise improves high-fat diet-induced depression remains unclear. In this study, 6-week-old male C57BL/6J mice were administered a high-fat diet (HFD, 60% kcal from fat) to a HFD model for 8 weeks. The RUN group also received 1 h of daily treadmill exercise in combination with the HFD. Depressive-like behaviors were evaluated by behavioral assessments for all groups. The key mediator of the effect of exercise on high-fat diet-induced depressive-like behaviors was detected by RNA-seq. The morphology and function of the neurons were evaluated via Nissl staining, Golgi staining, electron microscopy and electrophysiological experiments. The results showed that exercise attenuated high-fat diet-induced depressive-like behavior and reversed hippocampal gene expression changes. RNA-seq revealed Wnt5a, which was a key mediator of the effect of exercise on high-fat diet-induced depressive-like behaviors. Further work revealed that exercise significantly activated neuronal autophagy in the hippocampal CA1 region via the Wnt5a/CamkII signaling pathway, which enhanced synaptic plasticity to alleviate HFD-induced depressive-like behavior. However, the Wnt5a inhibitor Box5 suppressed the ameliorative effects of exercise. Therefore, this work highlights the critical role of Wnt5a, which is necessary for exercise to improve high-fat diet-induced depression.”

”

Wu, J., Xu, H., Wang, S. et al. Regular exercise ameliorates high-fat diet-induced depressive-like behaviors by activating hippocampal neuronal autophagy and enhancing synaptic plasticity. Cell Death Dis 15, 737 (2024). https://doi.org/10.1038/s41419-024-07132-4

https://www.nature.com/articles/s41419-024-07132-4

Abstract: Caloric restriction extends healthy lifespan in multiple species. Intermittent fasting, an alternative form of dietary restriction, is potentially more sustainable in humans, but its effectiveness remains largely unexplored. Identifying the most efficacious forms of dietary restriction is key for developing interventions to improve human health and longevity. Here we performed an extensive assessment of graded levels of caloric restriction (20% and 40%) and intermittent fasting (1 and 2 days fasting per week) on the health and survival of 960 genetically diverse female mice. We show that caloric restriction and intermittent fasting both resulted in lifespan extension in proportion to the degree of restriction. Lifespan was heritable and genetics had a larger influence on lifespan than dietary restriction. The strongest trait associations with lifespan included retention of body weight through periods of handling—an indicator of stress resilience, high lymphocyte proportion, low red blood cell distribution width and high adiposity in late life. Health effects differed between interventions and exhibited inconsistent relationships with lifespan extension. 40% caloric restriction had the strongest lifespan extension effect but led to a loss of lean mass and changes in the immune repertoire that could confer susceptibility to infections. Intermittent fasting did not extend the lifespan of mice with high pre-intervention body weight, and two-day intermittent fasting was associated with disruption of erythroid cell populations. Metabolic responses to dietary restriction, including reduced adiposity and lower fasting glucose, were not associated with increased lifespan, suggesting that dietary restriction does more than just counteract the negative effects of obesity. Our findings indicate that improving health and extending lifespan are not synonymous and raise questions about which end points are the most relevant for evaluating aging interventions in preclinical models and clinical trials.

Di Francesco, A., Deighan, A.G., Litichevskiy, L. et al. Dietary restriction impacts health and lifespan of genetically diverse mice. Nature (2024). https://doi.org/10.1038/s41586-024-08026-3

https://www.nature.com/articles/s41586-024-08026-3

Climbing stairs is associated with a longer life, according to research presented today at ESC Preventive Cardiology 2024, a scientific congress of the European Society of Cardiology (ESC).1

https://www.sciencedaily.com/releases/2024/04/240426110051.htm

Abstract:

Dopamine’s role as the principal neurotransmitter in motor functions has long been accepted. We broaden this conventional perspective by demonstrating the involvement of non-dopaminergic mechanisms. In mouse models of Parkinson’s disease, we observed that L-DOPA elicited a substantial motor response even when its conversion to dopamine was blocked by inhibiting the enzyme aromatic amino acid decarboxylase (AADC). Remarkably, the motor activity response to L-DOPA in the presence of an AADC inhibitor (NSD1015) showed a delayed onset, yet greater intensity and longer duration, peaking at 7 h, compared to when L-DOPA was administered alone. This suggests an alternative pathway or mechanism, independent of dopamine signalling, mediating the motor functions. We sought to determine the metabolites associated with the pronounced hyperactivity observed, using comprehensive metabolomics analysis.

Our results revealed that the peak in motor activity induced by NSD1015/L-DOPA in Parkinson’s disease mice is associated with a surge (20-fold) in brain levels of the tripeptide ophthalmic acid (also known as ophthalmate in its anionic form). Interestingly, we found that administering ophthalmate directly to the brain rescued motor deficits in Parkinson’s disease mice in a dose-dependent manner. We investigated the molecular mechanisms underlying ophthalmate’s action and discovered, through radioligand binding and cAMP-luminescence assays, that ophthalmate binds to and activates the calcium-sensing receptor (CaSR).

Additionally, our findings demonstrated that a CaSR antagonist inhibits the motor-enhancing effects of ophthalmate, further solidifying the evidence that ophthalmate modulates motor functions through the activation of the CaSR. The discovery of ophthalmate as a novel regulator of motor function presents significant potential to transform our understanding of brain mechanisms of movement control and the therapeutic management of related disorders.

Sammy Alhassen, Derk Hogenkamp, Hung Anh Nguyen, Saeed Al Masri, Geoffrey W Abbott, Olivier Civelli, Amal Alachkar, Ophthalmate is a new regulator of motor functions via CaSR: implications for movement disorders, Brain, Volume 147, Issue 10, October 2024, Pages 3379–3394, https://doi.org/10.1093/brain/awae097

https://academic.oup.com/brain/article/147/10/3379/7636309

Abstract: 

Background: Smoking is the leading behavioural risk factor for mortality globally, accounting for more than 175 million deaths and nearly 4·30 billion years of life lost (YLLs) from 1990 to 2021. The pace of decline in smoking prevalence has slowed in recent years for many countries, and although strategies have recently been proposed to achieve tobacco-free generations, none have been implemented to date. Assessing what could happen if current trends in smoking prevalence persist, and what could happen if additional smoking prevalence reductions occur, is important for communicating the effect of potential smoking policies.

Methods: In this analysis, we use the Institute for Health Metrics and Evaluation’s Future Health Scenarios platform to forecast the effects of three smoking prevalence scenarios on all-cause and cause-specific YLLs and life expectancy at birth until 2050. YLLs were computed for each scenario using the Global Burden of Disease Study 2021 reference life table and forecasts of cause-specific mortality under each scenario. The reference scenario forecasts what could occur if past smoking prevalence and other risk factor trends continue, the Tobacco Smoking Elimination as of 2023 (Elimination-2023) scenario quantifies the maximum potential future health benefits from assuming zero percent smoking prevalence from 2023 onwards, whereas the Tobacco Smoking Elimination by 2050 (Elimination-2050) scenario provides estimates for countries considering policies to steadily reduce smoking prevalence to 5%. Together, these scenarios underscore the magnitude of health benefits that could be reached by 2050 if countries take decisive action to eliminate smoking. The 95% uncertainty interval (UI) of estimates is based on the 2·5th and 97·5th percentile of draws that were carried through the multistage computational framework.

Findings: Global age-standardised smoking prevalence was estimated to be 28·5% (95% UI 27·9-29·1) among males and 5·96% (5·76-6·21) among females in 2022. In the reference scenario, smoking prevalence declined by 25·9% (25·2-26·6) among males, and 30·0% (26·1-32·1) among females from 2022 to 2050. Under this scenario, we forecast a cumulative 29·3 billion (95% UI 26·8-32·4) overall YLLs among males and 22·2 billion (20·1-24·6) YLLs among females over this period. Life expectancy at birth under this scenario would increase from 73·6 years (95% UI 72·8-74·4) in 2022 to 78·3 years (75·9-80·3) in 2050. Under our Elimination-2023 scenario, we forecast 2·04 billion (95% UI 1·90-2·21) fewer cumulative YLLs by 2050 compared with the reference scenario, and life expectancy at birth would increase to 77·6 years (95% UI 75·1-79·6) among males and 81·0 years (78·5-83·1) among females. Under our Elimination-2050 scenario, we forecast 735 million (675-808) and 141 million (131-154) cumulative YLLs would be avoided among males and females, respectively. Life expectancy in 2050 would increase to 77·1 years (95% UI 74·6-79·0) among males and 80·8 years (78·3-82·9) among females.

Interpretation: Existing tobacco policies must be maintained if smoking prevalence is to continue to decline as forecast by the reference scenario. In addition, substantial smoking-attributable burden can be avoided by accelerating the pace of smoking elimination. Implementation of new tobacco control policies are crucial in avoiding additional smoking-attributable burden in the coming decades and to ensure that the gains won over the past three decades are not lost.

GBD 2021 Tobacco Forecasting Collaborators. Forecasting the effects of smoking prevalence scenarios on years of life lost and life expectancy from 2022 to 2050: a systematic analysis for the Global Burden of Disease Study 2021. Lancet Public Health. 2024 Oct;9(10):e729-e744. doi: 10.1016/S2468-2667(24)00166-X. PMID: 39366729.

https://pubmed.ncbi.nlm.nih.gov/39366729/

Highlights

Beatriz Muñoz Ospina, Natalia Cadavid-Ruiz, The effect of aerobic exercise on serum brain-derived neurotrophic factor (BDNF) and executive function in college students, Mental Health and Physical Activity, Volume 26,2024,100578, https://doi.org/10.1016/j.mhpa.2024.100578.

https://www.sciencedirect.com/science/article/pii/S1755296624000036

See also:

Tang SW, Chu E, Hui T, Helmeste D, Law C. Influence of exercise on serum brain-derived neurotrophic factor concentrations in healthy human subjects. Neurosci Lett. 2008 Jan 24;431(1):62-5. doi: 10.1016/j.neulet.2007.11.019. Epub 2007 Nov 17. PMID: 18068900.

https://pubmed.ncbi.nlm.nih.gov/18068900/