PFKFB3-driven vascular smooth muscle cell glycolysis promotes vascular calcification via the altered FoxO3 and lactate production

MicroRNAs in vascular smooth muscle cells: Mechanisms, therapeutic potential, and advances in delivery systems

Vascular smooth muscle cells (VSMCs) are essential players in a wide range of physiological processes, and their phenotypic transitions are critical in the development of vascular diseases such as atherosclerosis (AS), restenosis, aortic dissection/aneurysm (AAD), chronic kidney disease (CKD), and diabetes mellitus (DM). MicroRNAs (miRNAs), a class of short non-coding RNAs, regulates key cellular functions like proliferation, migration, and apoptosis by modulating gene expression. Numerous studies have shown that various miRNAs play pivotal roles in the pathophysiological processes of VSMCs, with VSMC phenotype switching being a key factor. To harness miRNAs as therapeutic tools, researchers have focused on developing efficient delivery vectors, including exosomes, nanoparticles, and viral vectors. Recently, the exploration of miRNA characteristics and delivery mechanisms has led to the emergence of innovative systems, such as scaffold-based localized delivery methods, platelet-like fusion lipid nanoparticles(PLPs), liposome-exosome hybrid carriers, and stimulus-responsive delivery systems like miRNA micelles. These cutting-edge delivery systems not only enhance our understanding of miRNA's role in disease but also offer promising new strategies for gene therapy, paving the way for more precise and effective treatments in the future.

Inflammation-induced PFKFB3-mediated glycolysis promoting myometrium contraction through the PI3K-Akt-mTOR pathway in preterm birth mice

Inflammation is a significant risk factor for preterm birth. Inflammation enhances glycolytic processes in various cell types and contributes to the development of myometrial contractions. However, the potential of inflammation to activate glycolysis in pregnant murine uterine smooth muscle cells (mUSMCs) and its role in promoting inflammatory preterm birth remain unexplored. In this study, lipopolysaccharide was employed to establish both cell and animal inflammation models. We found that inflammation of mUSMCs during late pregnancy could initiate glycolysis and promote cell contraction. Subsequently, the inhibition of glycolysis using the glycolysis inhibitor 2-deoxyglucose can reverse inflammation-induced cell contraction. The expression of 6-phosphofructokinase 2 kinase (PFKFB3) was significantly upregulated in mUSMCs following lipopolysaccharide stimulation. In addition, lactate accumulation and enhanced contraction were observed. Inhibition of PFKFB3 reversed the lactate accumulation and enhanced contraction induced by inflammation. We also found that inflammation activated the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt)-mammalian target of the rapamycin (mTOR) pathway, leading to the upregulation of PFKFB3 expression. The PI3K-Akt pathway inhibitor LY294002 and the mTOR pathway inhibitor rapamycin effectively inhibited the upregulation of PFKFB3 protein expression, lactate production, and the enhancement of cell contraction induced by lipopolysaccharide. This study indicates that inflammation regulates PFKFB3 through the PI3K-Akt-mTOR pathway, which enhances the glycolytic process in pregnant mUSMCs, ultimately leading to myometrial contraction.NEW & NOTEWORTHY Expression of PFKFB3, a key enzyme in glycolysis, was significantly upregulated both in the mUSMCs and myometrium of mice during late pregnancy after lipopolysaccharide stimulation. Activation of the PI3K-Akt-mTOR pathway enhanced PFKFB3 expression, which is involved in the initiation of glycolysis. Inflammation-activated PFKFB3 via the PI3K-Akt-mTOR pathway, which enhances the cellular glycolytic process and thus promotes myometrium contraction in pregnancy.

The Role of Mitochondrial Dysfunction in CKD-Related Vascular Calcification: From Mechanisms to Therapeutics

Vascular calcification (VC) is a common complication of chronic kidney disease (CKD) and is closely associated with cardiovascular events. The transdifferentiation of vascular smooth muscles (VSMCs) into an osteogenic phenotype is hypothesized to be the primary cause underlying VC. However, there is currently no effective clinical treatment for VC. Growing evidence suggests that mitochondrial dysfunction accelerates the osteogenic differentiation of VSMCs and VC via multiple mechanisms. Therefore, elucidating the relationship between the osteogenic differentiation of VSMCs and mitochondrial dysfunction may assist in improving VC-related adverse clinical outcomes in patients with CKD. This review aimed to summarize the role of mitochondrial biogenesis, mitochondrial dynamics, mitophagy, and metabolic reprogramming, as well as mitochondria-associated oxidative stress (OS) and senescence in VC in patients with CKD to offer valuable insights into the clinical treatment of VC.

MiR-26b-5p/TET3 regulates the osteogenic differentiation of human bone mesenchymal stem cells and bone reconstruction in female rats with calvarial defects

BACKGROUND

MicroRNAs (miRNAs) play critical roles in the osteogenic differentiation of human bone mesenchymal stem cells (hBMSCs), but the mechanism by which miRNAs indirectly modulate osteogenesis remains unclear. Here, we explored the mechanism by which miRNAs indirectly modulate gene expression through histone demethylases to promote bone regeneration.

METHODS AND RESULTS

Bioinformatics analysis was performed on hBMSCs after 7 days of osteogenic induction. The differentially expressed miRNAs were screened, and potential target mRNAs were identified. To determine the bioactivity and stemness of hBMSCs and their potential for bone repair, we performed wound healing, Cell Counting Kit-8 (CCK-8), real-time reverse transcription quantitative polymerase chain reaction (RT‒qPCR), alkaline phosphatase activity, alizarin red S (ARS) staining and radiological and histological analyses on SD rats with calvarial bone defects. Additionally, a dual-luciferase reporter assay was utilized to investigate the interaction between miR-26b-5p and ten-eleven translocation 3 (TET3) in human embryonic kidney 293T cells. The in vitro and in vivo results suggested that miR-26b-5p effectively promoted the migration, proliferation and osteogenic differentiation of hBMSCs, as well as the bone reconstruction of calvarial defects in SD rats. Mechanistically, miR-26b-5p bound to the 3' untranslated region of TET3 mRNA to mediate gene silencing.

CONCLUSIONS

MiR-26b-5p downregulated the expression of TET3 to increase the osteogenic differentiation of hBMSCs and bone repair in rat calvarial defects. MiR-26b-5p/TET3 crosstalk might be useful in large-scale critical bone defects.

Gamut of glycolytic enzymes in vascular smooth muscle cell proliferation: Implications for vascular proliferative diseases

Vascular smooth muscle cells (VSMCs) are the predominant cell type in the media of the blood vessels and are responsible for maintaining vascular tone. Emerging evidence confirms that VSMCs possess high plasticity. During vascular injury, VSMCs switch from a "contractile" phenotype to an extremely proliferative "synthetic" phenotype. The balance between both strongly affects the progression of vascular remodeling in many cardiovascular pathologies such as restenosis, atherosclerosis and aortic aneurism. Proliferating cells demand high energy requirements and to meet this necessity, alteration in cellular bioenergetics seems to be essential. Glycolysis, fatty acid metabolism, and amino acid metabolism act as a fuel for VSMC proliferation. Metabolic reprogramming of VSMCs is dynamically variable that involves multiple mechanisms and encompasses the coordination of various signaling molecules, proteins, and enzymes. Here, we systemically reviewed the metabolic changes together with the possible treatments that are still under investigation underlying VSMC plasticity which provides a promising direction for the treatment of diseases associated with VSMC proliferation. A better understanding of the interaction between metabolism with associated signaling may uncover additional targets for better therapeutic strategies in vascular disorders.