Age-related osteoporosis is characterized by the deterioration in bone volume and strength, partly due to the dysfunction of bone marrow mesenchymal stromal/stem cells (MSCs) during aging. Alpha-ketoglutarate (αKG) is an essential intermediate in the tricarboxylic acid (TCA) cycle. Studies have revealed that αKG extends the lifespan of worms and maintains the pluripotency of embryonic stem cells (ESCs). Here, we show that the administration of αKG increases the bone mass of aged mice, attenuates age-related bone loss, and accelerates bone regeneration of aged rodents. αKG ameliorates the senescence-associated (SA) phenotypes of bone marrow MSCs derived from aged mice, as well as promoting their proliferation, colony formation, migration, and osteogenic potential. Mechanistically, αKG decreases the accumulations of H3K9me3 and H3K27me3, and subsequently upregulates BMP signaling and Nanog expression. Collectively, our findings illuminate the role of αKG in rejuvenating MSCs and ameliorating age-related osteoporosis, with a promising therapeutic potential in age-related diseases.

Alveolar bone is the thickened ridge of jaw bone that supports teeth. It is subject to constant occlusal force and pathogens invasion, and is therefore under active bone remodeling and immunomodulation. Alveolar bone holds a distinct niche from long bone considering their different developmental origin and postnatal remodeling pattern. However, a systematic explanation of alveolar bone at single-cell level is still lacking. Here, we construct a single-cell atlas of mouse mandibular alveolar bone through single-cell RNA sequencing (scRNA-seq). A more active immune microenvironment is identified in alveolar bone, with a higher proportion of mature immune cells than in long bone. Among all immune cell populations, the monocyte/macrophage subpopulation most actively interacts with mesenchymal stem cells (MSCs) subpopulation. Alveolar bone monocytes/macrophages express a higher level of Oncostatin M (Osm) compared to long bone, which promotes osteogenic differentiation and inhibits adipogenic differentiation of MSCs. In summary, our study reveals a unique immune microenvironment of alveolar bone, which may provide a more precise immune-modulatory target for therapeutic treatment of oral diseases.

In consideration of the advantages of sinus floor augmentation and immediate implant placement, our clinical result confirms that it is promising to combine the 2 techniques for replacing maxillary molars especially when using residual roots as implant orientation and taking full advantage of the interradicular crest bone.

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A series of dual functionalized ionic liquids with metal chelate cations from surfactant and alkali metal salt were designed, prepared, and used for SO2 capture. The effect of metal ions, coordination number, anionic structures, temperature, and pressure on SO2 absorption was investigated. The interaction of these functionalized ionic liquids with SO2 was explained by spectroscopic investigation. The results showed that these metal-containing ionic liquids exhibited high absorption capacity through a combination of physical and chemical interaction of SO2 with basic anions and ether-containing cations as well as excellent reversibility (21 recycles). Considering the easy preparation, low cost, and excellent performance, these dual functionalized metal-containing ionic liquids provide significant improvements over traditional ionic liquids, indicating the promise for industrial application in SO2 capture.