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Teens who use cannabis may face a substantially greater risk of developing serious mental health conditions, including psychotic and bipolar disorders, according to a study of more than 463,000 adolescents. Researchers found cannabis use often preceded these diagnoses by nearly two years, strengthening concerns about its long-term effects on developing brains.

Researchers have identified a vitamin B12–based compound that can cross the blood-brain barrier and home in on glioblastoma tumors. In animal studies, the compound accumulated preferentially in tumor tissue and delivered sustained nitric oxide directly to cancer cells. It also worked synergistically with existing glioblastoma treatments, significantly enhancing their tumor-fighting effects.

Aging may trigger the appearance of specialized stem cells that supercharge the body's ability to create new belly fat. The discovery reveals a potential biological driver of middle-age weight gain and a promising target for future anti-obesity treatments.

Hippocampal atrophy across the lifespan is associated with cognitive decline, as is difficulty understanding speech-in-noise. The hippocampus contains subfields with distinct functions, but their involvement in hearing-related differences is unknown. Here, we used HippUnfold, an automated hippocampal unfolding and subfield segmentation method, together with Multiple Factor Analysis (MFA) to examine shared variance across hippocampal structure, hearing-related function, and cognition in younger...

Aging disrupts physiological homeostasis, impairing thermoregulation, metabolism, and water balance, but the underlying neural mechanisms remain unclear. Here, we identify arginine vasopressin (AVP) neurons in the supraoptic nucleus (SON) of the hypothalamus as a critical driver of these changes in male mice. Single-nucleus RNA-sequencing revealed Avp among the most upregulated neuronal transcripts with age. Aged SON^(AVP) neurons displayed enlarged size and heightened excitability, features...

The goal of developing interventions to slow ageing is not only lifespan extension but more importantly to increase healthspan, the period of life spent in active good health. Nutritional interventions have emerged as a potential strategy to maintain health with age. Testing these interventions for effects on human ageing would take several years and require large cohort sizes. We therefore employed C. elegans as a rapidly ageing model organism to investigate the effects of two commercially...

CONCLUSIONS: This study indicates that retaining ≥ 20 teeth, brushing at least once daily, and using dentures are associated with a lower likelihood of anxiety symptoms among the elderly population. Further prospective studies are warranted to confirm these associations.

CONCLUSION: Advancing age is strongly associated with an increased burden of multimorbidity, which is intricately linked to depressive symptoms, diminished HRQoL, reduced muscular strength, central adiposity, and physical inactivity. These findings highlight the urgent need for integrated interventions in institutionalised older adults in sub-Saharan Africa and should inform policy reform aimed at strengthening long-term care and healthy ageing strategies.

CONCLUSION: This study highlights how older adults' perceptions of peers' OA are shaped by interpersonal impressions and social norms. Charisma, warmth, and facial expression could reduce the importance of specific orofacial features, whereas missing teeth, visible poor oral health, or appearance changes perceived as outside age-appropriate norms could trigger assumptions about lifestyle, vulnerability, or self-care.

CONCLUSIONS: Pre-social frailty and social frailty are common health challenges faced by community-dwelling older adults in China. Recent data indicate that the prevalence of these conditions remains high; although the prevalence is the very high heterogeneity and should be interpreted with caution, it nevertheless underscores the necessity and urgency of implementing effective interventions. Early identification and intervention for individuals at risk of social frailty are of critical...

Japan has one of the world's longest life expectancies, yet biomarkers associated with disability and mortality in very old adults remain uncertain. The goal of this study was to identify plasma proteins associated with incident disability and mortality in community-dwelling octogenarians. Two prospective cohorts were analyzed: the Kawasaki Aging Well-being Project (KAWP; 2017-2018; 4.5-year follow-up) as discovery and Invecchiare in Chianti (InCHIANTI; 1998-2000; 15-year follow-up) for external...

Mitochondrial DNA (mtDNA) mutations are hallmarks of aging. mtDNA in all opisthokonts is replicated exclusively by DNA Polymerase γ (Pol γ; encoded by POLG). PolgD257A/D257A mice, lacking Pol γ exonuclease proofreading (exo-), exhibit premature aging and higher mtDNA mutation rates than Polgwt/wt (exo+) mice. Using short-read sequencing and the ultra-sensitive LostArc indel-junction detection pipeline, we analyzed mtDNA from exo- and exo+ mice across 10 tissues. Indel-junction frequency,...

The battle between butter and margarine comes down to chemistry. Butter’s naturally occurring fats create rich flavors, golden browning, and flaky baked goods, while margarine’s modified plant oils offer consistency and a longer shelf life. Although both contain mostly fat, their different structures influence how they behave in recipes. Understanding those differences can help you choose the right one for cooking, baking, or health goals.

A new study found that fructose and glucose may look the same on a nutrition label, but the brain treats them very differently. In mice, glucose strongly reduced activity in hunger-promoting brain cells, while fructose had a much weaker effect. High-fructose corn syrup triggered a stronger response and was preferred by the animals. The findings suggest that the type of sugar—not just the calories—can influence appetite and food preferences.

The NLRP3 inflammasome has been implicated in a wide range of human diseases, including cardiovascular, metabolic, neurodegenerative (such as Alzheimer's disease), and other age-related conditions. This has positioned NLRP3 as a promising pharmacological target. Numerous studies have shown that complete NLRP3 ablation can prevent or mitigate these diseases. However, total elimination of NLRP3 is not a feasible therapeutic strategy for the millions of patients affected by these degenerative...

Growth/differentiation factor-15 (GDF15) is a secreted cytokine strongly associated with dementia risk. However, the extent to which GDF15 represents a biomarker and driver of dementia risk remains unclear. Across multiple cohorts, we demonstrated that plasma GDF15 is associated with greater dementia risk over 15- to 25-year follow-up periods when measured in midlife, with stronger associations observed for vascular, compared to Alzheimer's disease (AD), dementia. Two-sample Mendelian...

Lysophosphatidylinositol (LPI) is an endogenous GPR55 agonist, yet its role in Alzheimer's disease (AD) remains unclear. Here, we performed serum metabolomic profiling in 5xFAD mice and observed a reduction in multiple LPI species prior to the onset of overt Aβ pathology, and this decrease was further corroborated in human cohort samples. Exogenous LPI treatment reduced cerebral Aβ deposition, improved performance in learning and memory behavioral tasks, reduced pathological microglial...

Alzheimer's disease (AD) commences with the preclinical stage where individuals remain cognitively unimpaired but already have AD pathology. As fluid and neuroimaging biomarker research progresses, AD has become defined biologically rather than based on traditional clinical symptoms. While the diagnosis of AD has been conceptually advanced by the AT(N) classification framework according to core biomarker profiles of amyloid-β (A), tau (T) and neurodegeneration (N), solely relying on biological...

The gut microbiome modulates metabolic and neurovascular processes implicated in Alzheimer's disease and related dementias (ADRD), but the underlying mechanisms remain unclear. Here, we identify the bacterial metabolite imidazole propionate (ImP) as a modifier of ADRD pathology. In a cohort of 1196 cognitively unimpaired adults, higher plasma ImP levels were associated with lower preclinical cognitive scores and biomarkers of ADRD, both cross-sectionally and longitudinally. Fecal metagenomic...

Cognitive flexibility declines early in Alzheimer's disease, yet the underlying circuit mechanisms remain unknown. Here, we report that young 5xFAD mice exhibit deficits in instrumental reversal learning prior to spatial memory impairment. This behavioral inflexibility is associated with abnormal neuronal reactivation in the medial prefrontal cortex and dorsomedial striatum. Electrophysiological recordings reveal that medial prefrontal cortex neurons are hyperexcitable and receive increased...