Vascular calcification (VC), which is categorized by intimal and medial calcification, depending on the site(s) involved within the vessel, is closely related to cardiovascular disease. Specifically, medial calcification is prevalent in certain medical situations, including chronic kidney disease and diabetes. The past few decades have seen extensive research into VC, revealing that the mechanism of VC is not merely a consequence of a high-phosphorous and -calcium milieu, but also occurs via delicate and well-organized biologic processes, including an imbalance between osteochondrogenic signaling and anticalcific events. In addition to traditionally established osteogenic signaling, dysfunctional calcium homeostasis is prerequisite in the development of VC. Moreover, loss of defensive mechanisms, by microorganelle dysfunction, including hyper-fragmented mitochondria, mitochondrial oxidative stress, defective autophagy or mitophagy, and endoplasmic reticulum (ER) stress, may all contribute to VC. To facilitate the understanding of vascular calcification, across any number of bioscientific disciplines, we provide this review of a detailed updated molecular mechanism of VC. This encompasses a vascular smooth muscle phenotypic of osteogenic differentiation, and multiple signaling pathways of VC induction, including the roles of inflammation and cellular microorganelle genesis.
The fungal strain Alternaria alternata JS0515 was isolated from Vitex rotundifolia (beach vitex). Twelve secondary metabolites, including one new altenusin derivative (1), were isolated. The isolated metabolites included seven known altenusin derivatives (2–8), two isochromanones (9, 10), one perylenequinone (11), and one benzocycloalkanone (12). Their structures were determined via 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), and computational electronic circular dichroism (ECD) analysis. Compounds 3 and 11 increased pyruvate dehydrogenase (PDH) activity in AD-293 human embryonic kidney cells and significantly inhibited PDH phosphorylation. The IC50 values of 3 and 11 were 32.58 and 27.82 μM, respectively.
Three undescribed bicyclo[3.2.1]octanoid neolignan glucosides, along with a known neolignan, were isolated from the leaves of Piper crocatum Ruiz & Pav. Their chemical structures were elucidated using extensive spectroscopic analyses including 1D and 2D NMR experiments and HR-ESI-MS analysis, as well as through comparison with previously reported data. Two compounds were assessed for their inhibitory effect against pyruvate dehydrogenase E1α S300 phosphorylation. The fluorescent image suggested that both compounds (60 µM) revealed a stronger inhibition effect than the positive control (dichloroacetate, DCA 5 mM), with IC50 values of 99.82 µM and 80.25 µM, respectively.