Publications by authors named "Alfonso Schiavi"

Article Synopsis
  • Mitochondria and lysosomes are interdependent organelles that affect each other's functions, where defects in one lead to issues in the other.
  • Recent research using RNA sequencing has revealed that mitochondrial defects lead to downregulation of cholesterol synthesis pathways, while lysosomal defects lead to their upregulation.
  • The study also identified the role of the transcription factor SREBF1 in this regulation and demonstrated that balancing calcium levels in lysosomes can alleviate some developmental issues linked to mitochondrial dysfunction in a model organism, C. elegans.
View Article and Find Full Text PDF
Article Synopsis
  • Mitochondria and lysosomes are interdependent organelles that play crucial roles in cellular signaling and metabolism, and defects in one can lead to issues in the other.
  • The study used RNA sequencing to compare the effects of primary defects in mitochondria and lysosomes, finding that the cholesterol synthesis pathway is differently regulated in each case—up-regulated in lysosomal defects and down-regulated in mitochondrial defects.
  • Additionally, the research identified that post-transcriptional regulation of the SREBF1 transcription factor influences cholesterol biosynthesis, and normalizing calcium levels in lysosomes can partially alleviate problems caused by mitochondrial deficiencies, as seen in models of mitochondrial diseases in C. elegans.
View Article and Find Full Text PDF

Alzheimer's disease is the most common age-associated neurodegenerative disorder and the most frequent form of dementia in our society. Aging is a complex biological process concurrently shaped by genetic, dietary and environmental factors and natural compounds are emerging for their beneficial effects against age-related disorders. Besides their antioxidant activity often described in simple model organisms, the molecular mechanisms underlying the beneficial effects of different dietary compounds remain however largely unknown.

View Article and Find Full Text PDF

Excessive iron accumulation or deficiency leads to a variety of pathologies in humans and developmental arrest in the nematode . Instead, sub-lethal iron depletion extends lifespan. Hypoxia preconditioning protects against severe hypoxia-induced neuromuscular damage across species but it has low feasible application.

View Article and Find Full Text PDF

Severe oxygen and iron deficiencies have evolutionarily conserved detrimental effects, leading to pathologies in mammals and developmental arrest as well as neuromuscular degeneration in the nematode Yet, similar to the beneficial effects of mild hypoxia, non-toxic levels of iron depletion, achieved with the iron chelator bipyridine or through frataxin silencing, extend lifespan through hypoxia-like induction of mitophagy. While the positive health outcomes of hypoxia preconditioning are evident, its practical application is rather challenging. Here, we thus test the potential beneficial effects of non-toxic, preconditioning interventions acting on iron instead of oxygen availability.

View Article and Find Full Text PDF

Complex-I-deficiency represents the most frequent pathogenetic cause of human mitochondriopathies. Therapeutic options for these neurodevelopmental life-threating disorders do not exist, partly due to the scarcity of appropriate model systems to study them. Caenorhabditis elegans is a genetically tractable model organism widely used to investigate neuronal pathologies.

View Article and Find Full Text PDF

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor whose activity can be modulated by polyphenols, such as curcumin. AhR and curcumin have evolutionarily conserved effects on aging. Here, we investigated whether and how the AhR mediates the anti-aging effects of curcumin across species.

View Article and Find Full Text PDF

Cisplatin is the most common drug in first-line chemotherapy against solid tumors. We and others have previously used the nematode Caenorhabditis elegans to identify genetic factors influencing the sensitivity and resistance to cisplatin. In this study, we used C.

View Article and Find Full Text PDF

The aging process is concurrently shaped by genetic and extrinsic factors. In this work, we screened a small library of natural compounds, many of marine origin, to identify novel possible anti-aging interventions in , a powerful model organism for aging studies. To this aim, we exploited a high-content microscopy platform to search for interventions able to induce phenotypes associated with mild mitochondrial stress, which is known to promote animal's health- and lifespan.

View Article and Find Full Text PDF

Genetic, dietary, and environmental factors concurrently shape the aging process. The aryl hydrocarbon receptor (AhR) was discovered as a dioxin-binding transcription factor involved in the metabolism of different environmental toxicants in vertebrates. Since then, the variety of pathophysiological processes regulated by the AhR has grown, ranging from immune response, metabolic pathways, and aging.

View Article and Find Full Text PDF

Aging is characterized by the deterioration of different cellular and organismal structures and functions. A typical hallmark of the aging process is the accumulation of dysfunctional mitochondria and excess iron, leading to a vicious cycle that promotes cell and tissue damage, which ultimately contribute to organismal aging. Accordingly, altered mitochondrial quality control pathways such as mitochondrial autophagy (mitophagy) as well as altered iron homeostasis, with consequent iron overload, can accelerate the aging process and the development and progression of different age-associated disorders.

View Article and Find Full Text PDF

Background Aryl hydrocarbon receptor (AHR)-deficient mice do not support the expansion of dendritic epidermal T cells (DETC), a resident immune cell population in the murine epidermis, which immigrates from the fetal thymus to the skin around birth. Material and Methods In order to identify the gene expression changes underlying the DETC disappearance in AHR-deficient mice, we analyzed microarray RNA-profiles of DETC, sorted from the skin of two-week-old AHR-deficient mice and their heterozygous littermates. In vitro studies were done for verification, and IL-10, AHR repressor (AHRR), and c-Kit deficient mice analyzed for DETC frequency.

View Article and Find Full Text PDF

Mild suppression of mitochondrial activity has beneficial effects across species. The nematode is a versatile, genetically tractable model organism widely employed for aging studies, which has led to the identification of many of the known evolutionarily conserved mechanisms regulating lifespan. In the pro-longevity effect of reducing mitochondrial function, for example by RNA interference, is only achieved if mitochondrial stress is applied during larval development.

View Article and Find Full Text PDF
Article Synopsis
  • Ageing is a major risk factor for chronic illnesses, but effective interventions to promote health during ageing are scarce.
  • Researchers found that the flavonoid 4,4'-dimethoxychalcone (DMC) can extend lifespan and slow down aging processes in various organisms, including yeast, worms, flies, and even mice.
  • DMC induces autophagy, a cellular process vital for its protective effects, and is derived from the plant Angelica keiskei koidzumi, known in traditional Asian medicine for promoting longevity and health.
View Article and Find Full Text PDF

Interventions that promote healthy aging are typically associated with increased stress resistance. Paradoxically, reducing the activity of core biological processes such as mitochondrial or insulin metabolism promotes the expression of adaptive responses, which in turn increase animal longevity and resistance to stress. In this study, we investigated the relation between the extended lifespan elicited by reduction in mitochondrial functionality and resistance to genotoxic stress.

View Article and Find Full Text PDF

Cockayne syndrome (CS), a hereditary form of premature aging predominantly caused by mutations in the gene, affects multiple organs including skin where it manifests with hypersensitivity toward ultraviolet (UV) radiation and loss of subcutaneous fat. There is no curative treatment for CS, and its pathogenesis is only partially understood. Originally considered for its role in DNA repair, Cockayne syndrome group B (CSB) protein most likely serves additional functions.

View Article and Find Full Text PDF

Oxidation of DNA bases, an inevitable consequence of oxidative stress, requires the base excision repair (BER) pathway for repair. Caenorhabditis elegans is a well-established model to study phenotypic consequences and cellular responses to oxidative stress. To better understand how BER affects phenotypes associated with oxidative stress, we characterised the C.

View Article and Find Full Text PDF

Autophagy and the circadian clock counteract tissue degeneration and support longevity in many organisms. Accumulating evidence indicates that aging compromises both the circadian clock and autophagy but the mechanisms involved are unknown. Here we show that the expression levels of transcriptional repressor components of the circadian oscillator, most prominently the human Period homologue , are strongly reduced in primary dermal fibroblasts from aged humans, while raising the expression of in the same cells partially restores diminished autophagy levels.

View Article and Find Full Text PDF

Frataxin is a nuclear-encoded mitochondrial protein involved in the biogenesis of Fe-S-cluster-containing proteins and consequently in the functionality of the mitochondrial respiratory chain. Similar to other proteins that regulate mitochondrial respiration, severe frataxin deficiency leads to pathology in humans--Friedreich's ataxia, a life-threatening neurodegenerative disorder--and to developmental arrest in the nematode C. elegans.

View Article and Find Full Text PDF

Progressive neuronal deterioration accompanied by sensory functions decline is typically observed during aging. On the other hand, structural or functional alterations of specific sensory neurons extend lifespan in the nematode Caenorhabditis elegans. Hormesis is a phenomenon by which the body benefits from moderate stress of various kinds which at high doses are harmful.

View Article and Find Full Text PDF

Mitochondria are highly dynamic organelles which play a central role in cellular homeostasis. Mitochondrial dysfunction leads to life-threatening disorders and accelerates the aging process. Surprisingly, on the other hand, a mild reduction of mitochondria functionality can have pro-longevity effects in organisms spanning from yeast to mammals.

View Article and Find Full Text PDF

Background And Aim: We identified a balanced de novo translocation involving chromosomes Xq25 and 8q24 in an eight year-old girl with a non-progressive form of congenital ataxia, cognitive impairment and cerebellar hypoplasia.

Methods And Results: Breakpoint definition showed that the promoter of the Protein Tyrosine Kinase 2 (PTK2, also known as Focal Adhesion Kinase, FAK) gene on chromosome 8q24.3 is translocated 2 kb upstream of the THO complex subunit 2 (THOC2) gene on chromosome Xq25.

View Article and Find Full Text PDF

Severe mitochondria deficiency leads to a number of devastating degenerative disorders, yet, mild mitochondrial dysfunction in different species, including the nematode Caenorhabditis elegans, can have pro-longevity effects. This apparent paradox indicates that cellular adaptation to partial mitochondrial stress can induce beneficial responses, but how this is achieved is largely unknown. Complete absence of frataxin, the mitochondrial protein defective in patients with Friedreich's ataxia, is lethal in C.

View Article and Find Full Text PDF