Aggregator

The folate and methionine cycles (Met-C) are regulated by vitamin B12 (B12), obtained exclusively from diet and microbiota. Met-C supports amino acid, nucleotide, and lipid biosynthesis and provides one-carbon moieties for methylation reactions. While B12 deficiency and polymorphisms in Met-C genes are clinically attributed to neurological and metabolic disorders, less is known about their cell-non-autonomous regulation of systemic physiological processes. Using a B12-sensitive Caenorhabditis...

Aging is one of the most prominent risk factors for neurodegeneration, yet the molecular mechanisms underlying the deterioration of old neurons are mostly unknown. To efficiently study neurodegeneration in the context of aging, we transdifferentiated primary human fibroblasts from aged healthy donors directly into neurons, which retained their aging hallmarks, and we verified key findings in aged human and mouse brain tissue. Here we show that aged neurons are broadly depleted of RNA-binding...

Jansen's metaphyseal chondrodysplasia (JMC) is a rare disorder caused by activating mutations in the parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor (PTH1R). Patients exhibit short stature, dysmorphic bones, and severe growth plate abnormalities, as well as hypercalcemia, hypercalciuria, hypophosphatemia, and reduced plasma PTH levels. Humanized PTH1R (hPTH1R) mice expressing the H223R-hPTH1R JMC mutation die early without breeding. We therefore generated and characterized a...

Bisphenol A (BPA) substitutes are widely used as food contact materials and consumer products, while the effects of pathophysiologically relevant concentrations of BPA substitutes on aging remain unclear. In this study, we used Caenorhabditis elegans (C. elegans) to investigate the effects of five BPA substitutes [bisphenol S (BPS), bisphenol B, bisphenol F (BPF), tetramethyl BPF, and 4,4'-(Perfluoropropane-2,2-diyl)diphenol] at pathophysiologically relevant exposure levels during aging and...

Recent advances in isolating cells based on visual phenotypes have transformed our ability to identify the mechanisms and consequences of complex traits. Micronucleus (MN) formation is a frequent outcome of genome instability, triggers extensive changes in genome structure and signaling coincident with MN rupture, and is almost exclusively defined by visual analysis. Automated MN detection in microscopy images has proved challenging, limiting discovery of the mechanisms and consequences of MN....

The loss of bone volume during aging is common in both men and women and can have substantial negative health impacts. Weakened bones can lead to fractures which in turn can result in hospitalization, decreased quality of life, and early death. The post-diagnosis treatment of osteoporosis has received the bulk of attention with less research focused on prevention and modifiable risk factors such as nutrition. Calcium and vitamin D supplementation has provided limited skeletal benefit in healthy...

A major aging hallmark is the accumulation of cellular senescence burden. Over time, senescent cells contribute to tissue deterioration through chronic inflammation and fibrosis driven by the senescence-associated secretory phenotype (SASP). The human ovary is one of the first organs to age, and prominent age-related fibroinflammation within the ovarian microenvironment is consistent with the presence of senescent cells, but these cells have not been characterized in the human ovary. We thus...

Rapid transmission through sexual networks raises fears of wider spread in the region

Plan for slashed units and mission to be presented at governor’s meeting next week

CDC takes a bigger hit than expected; support for international HIV, malaria, TB, and vaccine efforts zeroed out