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Multi-omic analysis of guided and unguided forebrain organoids reveals differences in cellular composition and metabolic profiles

The differences in guided and unguided forebrain organoids.

The differences arising from guided or unguided differentiation of human forebrain organoids is not well understood.

The researchers perform a multiomic analysis of forebrain organoids generated by these two key methods.

The researchers demonstrate that guided forebrain organoids contained a larger proportion of neurons, including GABAergic interneurons, whereas the unguided organoids contained significantly more choroid plexus, radial glia, and astrocytes at later stages.

They also show increased levels of oxidative phosphorylation and fatty acid β-oxidation in the unguided forebrain organoids and a higher reliance on glycolysis in the guided forebrain organoids. sciencenewshighlights ScienceMission https://sciencemission.com/guided-and-unguided-forebrain-organoids


Øhlenschlæger et al. perform a multi-omic analysis of forebrain organoids generated by two key methods, guided and unguided differentiation. They document significant differences in the cell type composition and metabolic profiles of the two forebrain organoid types, providing a resource and methodological guide for the neural organoid field.

Tumor-derived aminopeptidase N promotes early stages of brain metastatic colonization

In this study, we identified the aminopeptidase CD13 as a key mediator in a subset of human BrMs originating from breast and lung cancers, with approximately 30% of samples exhibiting cancer cell-specific CD13 expression. Notably, this prevalence aligns with previous reports in breast and lung primary tumors. In BC, CD13 cancer cell expression was documented in 36% of patient samples analyzed, with higher rates in invasive ductal carcinoma,31 while in lung cancer, 35% of patients analyzed were positive for cancer cell CD13 expression.32 These observations suggest that CD13 expression is maintained during metastatic progression to the brain, underscoring its potential as a therapeutic target. Importantly, CD13 expression in primary lung cancer is associated with significantly reduced survival, with a similar trend in BC.31,32 Consistent with these data, we show here that patients with HER2+ BC with CD13high tumors have significantly poorer clinical outcomes. These findings emphasize the importance of stratifying patients by CD13 status to better assess both its prognostic significance and therapeutic potential.

To gain mechanistic insight into CD13 function, we employed murine BrM models from three primary origins (breast, lung, and melanoma) that recapitulate distinct stages of the metastatic cascade. Notably, only the breast-BrM model exhibited robust CD13 expression, suggesting that lung cancer and melanoma may rely on alternative, CD13-independent mechanisms to colonize the brain. CD13 knockdown in breast-BrM cells significantly prolonged survival and reduced metastatic seeding following intracardiac injection. This effect was less pronounced when cancer cells were introduced directly into the brain parenchyma (intracranial injection) or implanted at the primary site (MFP), underscoring CD13’s predominant role during the initial colonization phase of metastasis.

Both gain-and loss-of-function experiments confirmed CD13’s functional importance in metastatic seeding. CD13 has been described as a moonlighting enzyme with diverse cellular functions relevant to regulating metastasis,16,17 including β1 integrin recycling,21 cell migration,21 and activation of the MAPK and PI3K pathways.33 Based on our RNA-seq analysis, CD13 overexpression may further enhance metastatic efficiency through activation of Rho family GTPases and effectors that orchestrate cytoskeletal remodeling, endothelial cell adhesion, and transendothelial migration.34 These features position CD13 as a compelling anti-cancer target; indeed, CD13 inhibition has been explored in several therapeutic development efforts. However, no brain-permeable CD13 inhibitor has yet been approved worldwide for clinical use,16 representing a critical gap in the translational landscape.

A New Alzheimer’s Target Emerges: Blocking One Protein Restores Memory in Mice

Researchers have identified a protein that links brain immune activity, metabolism, and amyloid clearance, suggesting a new way to enhance current Alzheimer’s treatments. Alzheimer’s disease can look like a set of grim headlines: soaring case counts, ballooning health care costs, and an aging pop

Mitochondrial specialization and signaling shape neuronal function

How neuronal function is shaped by mitochondria.

Despite the established links between mitochondrial dysfunction and neuronal disorders, the specialization of mitochondria to support the specific demands of neurons has been less extensively explored.

Proper mitochondrial positioning influences an array of neuronal functions and processes, from neurodevelopment through synaptic transmission, due to the participation of mitochondria as local ATP suppliers, Ca2+ sinks, and sites of neurotransmitter synthesis.

In neurons, mitochondria are also crucial for local translation in axons and dendrites, to which they provide both local ATP and mRNA transport. In this way, mitochondria emerge as centers for neuronal plasticity sciencenewshighlights ScienceMission https://sciencemission.com/Mitochondrial-specialization


Neurons are specialized cells designed to process information and transmit it, often across long distances. In many neurons, the axonal volume far exceeds the somato-dendritic volume, creating a need for long-range transport and local polarization mechanisms. In addition, action potential firing and restoration of ionic gradients, as well as dynamic changes in synaptic plasticity, further increase the energetic demands of neurons. In this review, we highlight the roles mitochondria play in vertebrate neuronal biology and how mitochondrial functionality is tuned to support the unique demands of neurons. We cover the influence of mitochondrial positioning, ATP generation and Ca2+ buffering on neuronal function, and explore the role of mitochondria in neurotransmitter metabolism and local protein translation.

Enhanced Selenium Supplement Extends Lifespan and Delays Multi‐Organs Aging by Regulating the Sik1 Pathway Through Maintaining Calcium Homeostasis

In healthy aging strategies, nutritional supplements synergize with optimized dietary and lifestyle interventions by modulating aging-related molecular pathways.[ 8, 9 ] Notably, NMN exerts multi-organ anti-aging effects by elevating NAD+ levels to activate the SIRT1 pathway, thereby significantly enhancing mitochondrial function while reducing oxidative stress and DNA damage.[ 10 ] Similarly, curcumin delays aging and related diseases through pleiotropic mechanisms involving oxidative stress regulation, anti-inflammatory actions, telomere maintenance, and sirtuin protein modulation.[ 11 ] However, practical applications face significant challenges: bioactive compounds like resveratrol and curcumin suffer from limited bioavailability due to poor aqueous solubility and first-pass metabolism, while excessive supplementation of antioxidants such as vitamins C/E may disrupt reactive oxygen species (ROS) signaling homeostasis, potentially inducing cellular toxicity or even increasing hemorrhagic risk.[ 12-14 ] Future development of anti-aging supplements should focus on: 1) innovative formulation strategies to enhance bioavailability; 2) optimized dosing regimens to minimize toxicity; and 3) long-term clinical studies to validate efficacy.

Selenium, an essential trace element with diverse biological activities, plays a critical role in healthy aging.[ 15-17 ] ≈1 billion people worldwide are affected by selenium deficiency, which is closely linked to neurological disorders, cardiovascular abnormalities, malignancies, and immune dysfunction.[ 18-20 ] Substantial evidence supports the anti-aging effects of selenium through multiple mechanisms: 1) Selenomethionine (SeMet) effectively suppresses Fe2+/H2O2- or Aβ-induced free radical generation, demonstrating therapeutic potential for Alzheimer’s disease characterized by oxidative stress;[ 21 ] 2) Selenium supplementation elevates serum GPx3 levels, a selenoprotein predominantly localized in the basement membrane of renal proximal tubules, modulating mitochondrial quality control pathways to mitigate heavy metal-induced renal aging;[ 22 ] and 3) Our recent findings reveal that selenium supplementation significantly attenuates age-related muscle atrophy by preserving redox homeostasis and regulating muscle protein metabolism.[ 23 ] Recent clinical trials in patients with advanced non-small cell lung cancer (NSCLC) demonstrated that oral administration of selenium nanoparticles (SeNPs) as a dietary supplement (200 µg day−1) in combination with Bev+AP chemotherapy significantly enhanced therapeutic outcomes compared to chemotherapy alone. The SeNPs combination group showed remarkable tumor regression, with progression disease rates decreasing dramatically from 50% to 0% and partial response rates increasing to 83.3%, along with significantly improved objective response rate and disease control rate.[ 24 ] Importantly, this regimen maintained excellent safety profiles without triggering fluctuations in pro-inflammatory or immunosuppressive cytokines. These compelling findings not only establish SeNPs as a safe and effective adjuvant therapy for advanced NSCLC but also provide valuable clinical translation data for nano-selenium formulations in oncology. Despite selenium’s proven benefits in reducing oxidative damage, maintaining genomic stability, and delaying telomere shortening, its narrow therapeutic window, limited bioavailability, and specific mechanisms in multi-organ protection during natural aging require further investigation.

Nanodelivery carriers have emerged as a next-generation platform for gene and drug delivery, offering tunable physicochemical properties such as size, composition, and surface modifications.[ 25 ] Our team has developed organically-bridged mesoporous silica nanoparticles (MSNs) by incorporating functional diselenide bonds into the silica framework at the molecular level, addressing the critical challenge of poor biodegradability in conventional silica materials.[ 26 ] This nanocarrier exhibits unique dual redox-responsive properties, allowing for more precise maintenance of redox homeostasis compared to traditional antioxidants, aligning with the core goal of preserving organismal homeostasis in anti-aging research. Building on this breakthrough, a comprehensive research framework was established: first, this study constructed a natural aging mouse model with MSNs, disulfide-bridged MSNs (SMSNs), commercially available SeMet as controls and then compared the effects of diselenide-bridged MSNs (SeMSNs) on lifespan extension, frailty delay, and multi-organ anti-aging. Next, key pathways and targets were identified through multi-organ transcriptome sequencing, followed by in-depth mechanistic studies. Finally, clinical translation was integrated by analyzing the correlation between serum selenium levels and aging biomarkers in the elderly, and validating the clinical effects of SeMSNs using primary adipose precursor cells (APCs) models. This systematic approach provides a solid theoretical foundation and clinical evidence for the application of nano-selenium in anti-aging research.

No current theory of consciousness is scientific

A letter by distinguished scientists directed at Integrated Information Theory sought to discredit a leading theory of consciousness as pseudoscience. That, argues Erik Hoel, was a mistake.

Hoel contends that as no theory of consciousness is currently empirically testable, it’s impossible for any of these theories to be scientific.

Hoel is a neuroscientist, neurophilosopher, and fiction writer. He’s been a close collaborator of Giulio Tononi, and a Forbes 30 under 30 in science.

“Consciousness, according to IIT, might be more widespread than we think, but it is neither universal nor arbitrary,” writes Hoel.

Tap the link to read more now.

Predicting Return Home After Moderate-to-Severe Traumatic Brain Injury

Background and ObjectivesDays alive and at home (DAH) is a validated outcome measure that captures health care transitions between time spent at home vs various nonhome care settings, offering a more nuanced patient-centered understanding of recovery. We…

MIT’s new brain tool could finally explain consciousness

Although the technology has been around for several years, it has not yet become a standard tool in neuroscience research. Now, two researchers at MIT are preparing new experiments using the technique and have published a paper that serves as a detailed guide, or “roadmap,” for applying it to the study of consciousness.

“Transcranial focused ultrasound will let you stimulate different parts of the brain in healthy subjects, in ways you just couldn’t before,” says Daniel Freeman, an MIT researcher and co-author of the paper. “This is a tool that’s not just useful for medicine or even basic science, but could also help address the hard problem of consciousness. It can probe where in the brain are the neural circuits that generate a sense of pain, a sense of vision, or even something as complex as human thought.”

Unlike other brain stimulation methods, transcranial focused ultrasound does not require surgery. It can reach deeper areas of the brain with greater precision than techniques such as transcranial magnetic or electrical stimulation.

Episode 2 — The Prospect of Immortality & Human Cryopreservation

Host: Kyle O’Brien — https://twitter.com/analog_kyle.

Guest: Emil Kendziorra — https://twitter.com/emilkendziorra.
Founder of @TomorrowBio.

Theme || the prospect of immortality & human cryopreservation.

Is Death just a Technical Problem we haven’t solved yet?

In this episode of State Change, Kyle O’Brien sits down with Emil Kendziorra, founder of Tomorrow Bio, to explore the science, ethics, and future of cryopreservation — the process that may one day allow humans (and even pets) to be revived centuries from now.

We talk about the brain, identity, consciousness, why people fear death, and what it means to rewrite the social contract when life extension becomes real.

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