Science Society

Dive into the microscopic realm of neural progenitor cells with Dr. Ernst of McGill University as we delve into the intricacies of FOXG1—a gene exclusively expressed in the brain—and its profound implications. From microcephaly to severe intellectual disabilities, the role of FOXG1 is more integral than previously thought. In a groundbreaking study, Dr. Ernst and his team meticulously modeled FOXG1 syndrome using cells from diagnosed patients and controls. The revelations? Cells with a FOXG1 loss demonstrated a marked reduction in proliferation, a skewed cell cycle ratio, and an intriguing increase in primary cilia. But what happens when the FOXG1 gene is manipulated? The engineered loss and subsequent repair of FOXG1 reveal its dose-dependent effects, painting a clear picture of its essential role in human brain cell growth. Whether you're curious about genetic functions in brain health or the potential future therapies for disorders like glioblastoma, this episode with Dr. Ernst promises a deep dive into the genetic heart of our most vital organ.

Keyword List:

McGill University

FOXG1 Syndrome

Neural Progenitor Cells

Microcephaly

Seizures

Intellectual Disability

Glioblastoma

Forebrain Cell Proliferation

Cell Cycle

Primary Cilia

Genetic Engineering

Human Brain Cell Growth

https://doi.org/10.1016/j.stemcr.2022.01.010

Journey with Dr. Levy into the heart of cellular fate determination and the role of the polycomb repressive complex 2 (PRC2) in it. Histone 3 lysine 27 methylation (H3K27me3) marks, crucial for cellular bifurcation during development, have remained a mystery—until now. Dr. Levy introduces the cutting-edge EBdCas9 technology, a fusion of a computationally designed protein and the infamous dCas9, to shed light on this enigmatic process. When targeted at specific genes, this tool reveals precise locations where H3K27me3 and EZH2 operate, leading to fascinating insights such as the discovery of a functional distal TATA box upstream of the TBX18 transcription start site.

Dive deeper to understand the power of EBdCas9, from revealing the most significant H3K27me3 marks in promoter regions to controlling transcriptional activation organically. Dr. Levy’s work also paints a larger picture about the nature of H3K27me3 marks on promoter regions, challenging our previous understanding and suggesting that many broad marks might be indiscriminate. With an eye to the future, this episode discusses the potential of EBdCas9 not only as an invaluable research tool but also as a revolutionary method to treat diseases like cancer. This isn't just about decoding genes; it's about rewiring our understanding of epigenomic memory, and how we might shape it for the future of medicine.

Keyword List:

• Epigenomic Regulation
• PRC2
• Histone 3 lysine 27 methylation (H3K27me3)
• EBdCas9 Technology
• dCas9
• TATA Box
• TBX18
• Gene Activation
• Transcriptional Activation
• TBP Recruitment
• Epigenomic Memory
• Cellular Fate Determination
• Cancer Treatment Potential

doi: 10.1016/j.celrep.2022.110457. PMID: 35235780.

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Step into the cutting-edge world of embryogenesis with Dr. Alejandro A-Castrejon from the Weizmann Institute of Science. While our grasp on the early stages of mammalian development has steadily grown over the years, the phase after implantation into the maternal uterus has remained somewhat elusive. But all that is about to change.

Dr. Alejandro A-Castrejon unveils groundbreaking platforms for the ex utero culture of post-implantation mouse embryos. This transformative approach allows researchers to mimic in utero development precisely from before gastrulation (at embryonic day, or E, 5.5) up until advanced organogenesis stages (E11) – all outside the womb. With a strategic mix of static and rotating bottle culture platforms, these embryos are nurtured in conditions that beautifully recreate their natural growth environment.

Dive into the nitty-gritty as we discuss how these cultured embryos, scrutinized via histological, molecular, and single-cell RNA sequencing analyses, mirror in utero development with unparalleled precision. This revolutionary method doesn’t just push the boundaries of what we thought was possible; it obliterates them, enabling researchers to undertake a slew of embryonic interventions and observations over six days, unfettered by the limitations of the uterine environment.

Beyond its scientific marvel, the system’s implications are vast and varied. From genetic modifications and chemical screens to tissue manipulation and advanced microscopy techniques, the doors to innovation swing wide open. By underlining the self-organizing prowess of embryos and expanding the realm of ex utero research across various mammalian species, Dr. A-Castrejon offers a tantalizing glimpse into the future of embryogenesis research.

Keyword List:

Weizmann Institute of Science

Embryogenesis

Ex utero culture

Post-implantation mouse embryos

Gastrulation

Organogenesis

Rotating bottle culture

Histological analysis

Single-cell RNA sequencing

Embryonic perturbations

Artificial embryogenesis

Mammalian species

In vitro recapitulation

https://doi.org/10.1038/s41586-021-03416-3

Dr. Van Zundert invites us on an enlightening journey into the intricate world of neurodegenerative diseases, specifically amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). These disorders have puzzled researchers for years, especially given the involvement of non-cell-autonomous mechanisms where toxic factors released by astrocytes lead to motorneuron (MN) damage. The heart of this mystery? A compound known as inorganic polyphosphate (polyP).

Delving deep into his research, Dr. Van Zundert unveils a startling discovery. Astrocytes derived from mice and patient-induced pluripotent stem cells (iPSCs) with mutations linked to ALS/FTD (including SOD1, TARDBP, and C9ORF72) exhibit a spike in their intracellular polyP levels. The consequence? Elevated polyP levels in astrocyte-conditioned media (ACM), which, when presented to MNs, has devastating effects.

However, hope looms on the horizon. By degrading or neutralizing polyP, Dr. Van Zundert and his team can successfully stave off ACM-induced MN death. To compound this groundbreaking discovery, postmortem analyses of ALS spinal cords revealed amplified polyP staining signals, and an uptick in polyP concentrations was noted in ALS cerebrospinal fluid (CSF).

This episode unravels the profound implications of these findings. Not only does excessive astrocyte-derived polyP emerge as a critical element in MN degeneration and a potential game-changer in ALS/FTD treatment, but polyP in CSF could revolutionize early detection, positioning itself as a pioneering biomarker for ALS/FTD.

Keyword List:

Neurodegenerative diseases

Amyotrophic lateral sclerosis (ALS)

Frontotemporal dementia (FTD)

Non-cell-autonomous mechanisms

Astrocytes

Motorneurons (MNs)

Inorganic polyphosphate (polyP)

Astrocyte-conditioned media (ACM)

iPSC-derived astrocytes

ALS/FTD-linked mutations

Biomarker

Cerebrospinal fluid (CSF)

Therapeutic target

https://doi.org/10.1016/j.neuron.2022.02.010

In a riveting conversation with Dr. Bohnert, we uncover the mysteries surrounding the biological process of aging. Contrary to popular belief, aging isn't a chaotic decline but a process governed at the molecular level. The spotlight today is on a unique botanical extract from Artemisia scoparia (SCO), which has been shown to promote fat storage, metabolic resiliency, and notably, extend the life span of the nematode Caenorhabditis elegans by an astonishing 40%.

Dr. Bohnert details how SCO's magic lies in its ability to elevate levels of unsaturated fats in worms. Inhibiting certain enzymes, which oversee the biosynthesis of these fatty acids, cancels out SCO's life-extending benefits. Furthermore, SCO influences fat regulation in these worms by inducing nuclear translocation of the transcription factor DAF-16/FOXO in a manner dependent on AMP-activated protein kinase.

Interestingly, while enhancing fat accumulation is a shared outcome of SCO in both worms and mammals, the mechanisms may vary across species. In mice, for example, SCO activates a receptor that regulates fat storage, which doesn't exist in C. elegans. This hints at potentially different pathways that are stimulated by SCO in different organisms.

The episode also touches on how SCO holds its own when compared to well-known anti-aging therapies like metformin and rapamycin, outperforming them in certain aspects, and showing fewer side effects. As the first study to highlight life-span extension through extract-driven fat accumulation, this discovery is both novel and groundbreaking. It paints a picture where increased unsaturated fats, typically associated with benefits against cardiovascular diseases and type-2 diabetes in humans, can be prohealth and antidisease.

For listeners intrigued by the practical application, Dr. Bohnert discusses the possibility of using SCO as a prohealth dietary supplement, especially as it enhances stress resistance and seems to counter age-related disorders even when administered later in life. As SCO treatments unfold, it's evident they engage specific longevity factors, displaying specificity in their mode of action.

In conclusion, Dr. Bohnert anticipates an exciting road ahead. With numerous bioactive compounds already identified in SCO, including chlorogenic acid which has shown to have some life-span extending properties, further research can reveal whether SCO and its components might revolutionize our understanding of longevity and healthy aging in mammals.

Keyword List:

Aging

Molecular control

Artemisia scoparia (SCO)

Fat storage

Metabolic resiliency

Caenorhabditis elegans

Life-span extension

Unsaturated fats

Transcription factor DAF-16/FOXO

AMP-activated protein kinase

Anti-aging therapies

Metformin

Rapamycin

Prohealth dietary supplement

Stress resistance

Chlorogenic acid.

https://doi.org/10.1093/gerona/glac040

In a groundbreaking study from Dr. Ying-Hui Fu's team at the University of California, we delve into the intriguing world of Familial Natural Short Sleepers (FNSS). These individuals, who naturally sleep less yet face no cognitive decline, might offer insights into slowing Alzheimer's disease. Join us as we discuss the compelling link between sleep quality and neurodegenerative disorders and how FNSS genetic mutations could become our secret weapon against Alzheimer's.

Keyword List:

Familial Natural Short Sleepers (FNSS)

Alzheimer's disease (AD)

Genetic mutations

DEC2-P384R

Npsr1-Y206H

Neurodegeneration

Amyloid plaques

Tau pathology

Sleep efficiency

University of California San Francisco

https://doi.org/10.1016/j.isci.2022.103964

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Long-distance electrodynamic intermolecular forces

Uncover the groundbreaking work of Marco Pettini and his team, who reveal a surprising force at play in the dance of biomolecules. With the use of two pioneering experiments, they bring to light the existence of long-range electrodynamic (ED) forces between molecules—forces that, until now, remained theoretical. These forces could dramatically change our understanding of cellular dynamics, potentially speeding up certain cellular processes and perhaps even playing a role in drug design. Dive deep with us as we explore this thrilling frontier, ponder its implications in evolution, and imagine its potential uses in biomedical innovation.

Keyword List:

Electrodynamic (ED) forces

Biomolecular interactions

Molecular biology

Aix-Marseille Univ.

Fluorescence correlation spectroscopy

Terahertz spectroscopy

Resonant forces

Molecular condensates

Adenosine triphosphate (ATP)

Biomolecular communications

Optogenetics

Drug design

Evolution

Molecular crowding

https://doi.org/10.1126/sciadv.abl5855

In today's episode, Dr. Morein enlightens us about an often under-recognized condition: Hoarding Disorder (HD). Traditionally associated with Obsessive-Compulsive Disorder (OCD), recent insights suggest a surprising connection between HD and Attention Deficit/Hyperactivity Disorder (ADHD).

Main Points:

Background on Hoarding Disorder (HD):

HD remains under-recognized and inadequately treated.

Though it generally manifests by early adulthood, most patients only seek help later in life, often leading to research predominantly focusing on older females.

HD vs. OCD:

Historically, HD was considered a variant of OCD.

However, recent studies indicate that many with HD display symptoms reminiscent of ADHD, particularly inattention.

Study Findings:

Among adults attending an ADHD clinic, a significant proportion (about 20%) exhibited clinically relevant hoarding symptoms, compared to only 2% in the control group.

Interestingly, this ADHD group with hoarding tendencies had an average age in their thirties, and approximately half were male.

Overall, hoarding severity was higher in the ADHD group compared to controls.

Notably, inattention stood out as the single most significant predictor of hoarding severity in patients.

Independent Study Verification:

An independent online UK sample was assessed to verify these findings.

The study reiterated the findings, with inattention, depression, and anxiety emerging as the top predictors for hoarding.

Approximately 3.2% of this sample identified having clinically significant hoarding tendencies.

Implications:

The research suggests a clear overlap between ADHD, particularly inattention, and HD.

Medical professionals should be vigilant in assessing HD in individuals diagnosed with ADHD.

Despite the potential to adversely impact daily functioning, patients with ADHD might not spontaneously disclose their hoarding issues.

There's a need for HD research to consider younger adults with ADHD, a demographic that offers a different age and gender distribution than what has been traditionally studied.

Conclusion:

Hoarding Disorder and ADHD might seem worlds apart, but as Dr. Morein's insights reveal, they could be intertwined in ways we've never imagined. With increasing awareness and timely intervention, we can provide better support and treatment strategies for those grappling with these challenges.

Join us next week as we delve deeper into another exciting topic. Stay curious and stay informed!

https://dx.doi.org/10.1016%2Fj.jpsychires.2021.12.024