Osteoclast-derived microRNA-containing exosomes selectively inhibit osteoblast activity.

MicroRNAs have an important role in bone homeostasis. However, the detailed mechanism of microRNA-mediated intercellular communication between bone cells remains elusive. Here, we report that osteoclasts secrete microRNA-enriched exosomes, by which miR-214 is transferred into osteoblasts to inhibit their function.

DDAH1 deficiency promotes intracellular oxidative stress and cell apoptosis via a miR-21-dependent pathway in mouse embryonic fibroblasts.

Asymmetric dimethylarginine (ADMA), an endogenous nitric oxide synthase (NOS) inhibitor, is degraded by dimethylarginine dimethylaminohydrolase 1 (DDAH1). Emerging evidence suggests that plasma ADMA accumulation, DDAH1 activity/expression reduction, and microRNA-21 (miR-21) upregulation are linked to disease pathology, but the mechanisms remain largely unknown. In the present study, we assessed the potential role of the ADMA-DDAH1-miR-21 pathway in the regulation of the cellular redox state and apoptosis using wild-type (WT) and DDAH1-knockout (KO) immortalized mouse embryonic fibroblasts (MEFs).

miR-214 promotes osteoclastogenesis by targeting Pten/PI3k/Akt pathway.

microRNA is necessary for osteoclast differentiation, function and survival. It has been reported that miR-199/214 cluster plays important roles in vertebrate skeletal development and miR-214 inhibits osteoblast function by targeting ATF4. Here, we show that miR-214 is up-regulated during osteoclastogenesis from bone marrow monocytes (BMMs) with macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL) induction, which indicates that miR-214 plays a critical role in osteoclast differentiation.

Spirostanol saponins derivated from the seeds of Trigonella foenum-graecum by β-glucosidase hydrolysis and their inhibitory effects on rat platelet aggregation.

Nine spirostanol saponins (1-9) and seven mixtures of 25 R and 25 S spirostanol saponin isomers (10-16) were obtained from the seeds of Trigonella foenum-graecum after enzymatic hydrolysis of the furostanol saponin fraction by β-glucosidase. Their structures were determined by NMR and MS spectroscopy. Among them, 1- 4, 6, 8, and 9 were new compounds and five, 11B, 12A, 13B, 14A, and 14B, were new structures observed from seven mixtures.