The C57BL/6N mouse substrain is a viable model of elastase-induced abdominal aortic aneurysm.

Aim: Compared with the C57BL/6N substrain, the C57BL/6J substrain is more susceptible to the angiotensin II (Ang II)-induced development of dissected abdominal aortic aneurysms (AAAs). The aim of this study was to elucidate whether the widely used C57BL/6N mouse substrain is as susceptible as the C57BL/6J mouse substrain to porcine pancreatic elastase (PPE) infusion-induced experimental nondissected AAA development. Methods: Experimental nondissected AAAs were induced in C57BL/6J and C57BL/6N mice via transient aortic luminal infusion of PPE. On Day 0 (baseline) and Day 14 after PPE infusion, the abdominal aortic diameter was directly measured. Aortic aneurysmal segment samples were collected, and histopathological analysis was performed. Results: On Day 14 after PPE infusion, aortic diameters were significantly increased in both mouse substrains (from approximately 0.51 to 1.24 mm in C57BL/6J mice and from 0.51 to 1.18 mm in C57BL/6N mice). The increase in diameter of all the mice exceeded 50% and met the criteria for AAA model establishment (143% and 135% in C57BL/6J mice and C57BL/6N mice, respectively). PPE infusion also induced obvious local aortic wall macrophage and T-cell infiltration, elastin degradation, smooth muscle cell depletion and high metallopeptidase (MMP)-2 and MMP-9 expression levels in C57BL/6N mice, but these differences were not significant compared with those in C57BL/6J mice. However, PPE infusion led to the recruitment of more B cells and the sprouting of more neovessels at the aneurysmal lesion site in C57BL/6J mice than in C57BL/6N mice. Conclusion: The C57BL/6N mouse substrain is suitable for establishing a model of AAA via elastase infusion.

Direct Effects of Inflammatory Cytokines on Mouse Uterine Contraction.

PROBLEM: Uterine contractions signal labor onset, with elevated pro-inflammatory cytokines playing a pivotal role. Prior studies have explored their effects on prostaglandins, oxytocin, and signaling pathways, but have overlooked their direct effects on uterine contractions. Here, we aim to investigate the direct effects of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) on contractions to ascertain if they have immediate observable effects like those reported for lipopolysaccharide (LPS) and other effects. METHOD OF STUDY: Tension recordings were used to assess the direct effects of cytokines and/or LPS on mouse uterine contractions. Calcium imaging was employed to observe calcium oscillations in cytokine-pretreated myometrial smooth muscle cells (MSMCs) in response to oxytocin. The release of inflammatory cytokines and chemokines from uterine explants after LPS and/or cytokines application was investigated using Luminex. RESULTS: IL-1ß, IL-6, and TNF-α rapidly enhanced contractions of term pregnant mouse uterus. LPS combined with TNF-α intensified contractions compared to LPS alone, although this effect was not statistically significant in our results (p > 0.050). Pretreatment of MSMCs with IL-1ß, IL-6, or TNF-α increased calcium oscillations in response to oxytocin. LPS and/or cytokine significantly stimulated the release of IL-1ß, IL-6, TNF-α, Chemokine (C-X-C motif) ligand 1 (CXCL1), and monocyte chemoattractant protein-1 (MCP1) from uterine explants in vitro. CONCLUSIONS: Inflammatory cytokines have short-term and long-term effects on mouse uterine contractions, which together contribute to progressively stronger contractions during labor.

Interplay of atherosclerosis and medial degeneration in human ascending aorta.

The previous understanding has been that atherosclerosis tends to increase distally from the ascending aorta, but recent studies and practical experience have indicated that atherosclerosis occurs in the ascending aorta more than previously thought. Medial degeneration is linked to aortic aneurysms, dissection and dilatation and has been related to increased mortality. There is a lack of data on the coexistence of atherosclerosis and medial degeneration in the ascending aorta and its outcome to clinical morbidity and mortality. Earlier studies have shown coexisting atherosclerosis and medial degeneration as significant risk indicators for coronary and cerebrovascular events. We aimed to analyze aortic specimens classified according to the consensus documents of the Society for Cardiovascular Pathology and the Association for European Cardiovascular Pathology particularly the comparison of variable morphological features with the atherosclerotic grade to gain more data about the coexistence of atherosclerosis and medial degeneration. We evaluated 217 specimens of human ascending aorta resected at Tampere University Heart Hospital because of aortic aneurysm, dissection or dilatation. None of the samples contained normal aortic morphology; atherosclerosis was found in a total of 75.8 % of the samples and medial degeneration in all the samples. The present study is mostly in agreement with earlier research regarding the prevalence of different histological findings, even though a higher prevalence of atherosclerosis was found compared with most studies. There was no statistically significant association between atherosclerosis and medial degeneration, but a higher atherosclerotic grade was significantly associated with the presence of smooth muscle cell nuclei loss, smooth muscle cell disorganisation, elastic fibre thinning and medial fibrosis. Our study reinforces the perception that atherosclerotic lesions significantly occur in the ascending aorta and coexist with individual components of the medial degeneration.

Inhibition of heterogeneous nuclear ribonucleoproteins A1 and oxidative stress reduces glycolysis via pyruvate kinase M2 in chronic thromboembolic pulmonary hypertension.

Background and Objective: Chronic thromboembolic pulmonary hypertension (CTEPH) is a lethal complication of pulmonary embolism involving pulmonary artery occlusion and microvascular disease. The glucose metabolism and reactive oxygen species (ROS) production may be perturbed in CTEPH, but the precise mechanisms are unclear. This study investigated glucose metabolism in CTEPH employing pulmonary endarterectomy (PEA)-derived pulmonary artery smooth muscle cells (PASMCs) and characterized the roles of pyruvate kinase M2 (PKM2) and its regulation by heterogeneous nuclear ribonucleoproteins A1 (hnRNPA1) and ROS in CTEPH. Methods: PEA tissues and blood samples of CTEPH patients were collected to study the levels of PKM2. Primary PASMCs were isolated from PEA tissues. We used small interfering RNAs to knock down PKM2 and hnRNPAI, and applied antioxidant N-acetylcysteine (NAC) and mito-TEMPO to reduce ROS production. The expression of glucometabolic genes, ROS production, glycolysis rate and proliferative and migratory activities were analyzed in PEA-derived PASMCs. Results: PKM2 levels in serum and PEA tissues of CTEPH patients were higher than that of the healthy controls. Compared to the control PASMCs, PEA-derived PASMCs showed increased PKM2 expression and ROS production. The rates of glycolysis, proliferation and migration were increased in PEA-PASMCs and could be mitigated by PKM2 downregulation through hnRNPA1 or ROS inhibition. Conclusions: Increased glycolysis and PKM2 expression were found in PEA-PASMCs. Inhibition of hnRNPA1 or ROS corrected the aberrant glycolysis, cell proliferation and migration by downregulating PKM2. Regulation of the hnRNPA1/PKM2 axis represents a potential therapeutic target for the treatment of CTEPH.

Pseudo-3D Topological Alignments Regulate Mechanotransduction and Maturation of Smooth Muscle Cells.

Smooth muscle cells (SMCs) sense and respond to mechanical stimuli in their extracellular microenvironments (ECMs), playing a crucial role in muscle tissue engineering. Increasing evidence from topological cues-mediated mechanotransduction of SMCs in ECMs has suggested some potential underlying mechanisms of how SMC functions and maturation are regulated by their mechanosensing leading to transduction. However, how the expression of yes-associated protein 1 (YAP) influences the phenotypic shift from synthetic to contractile is still controversial. Here, pseudo-3D topological alignments mimicking native muscle tissues are generated using laser-cutter engraving to explore the influence of topological cues on SMC mechanotransduction and maturation. The analysis of topological cue-mediated mechanotransduction and maturation marker expression revealed YAP is involved in mechanotransduction for SMCs cultured on cross-patterned substrates in the presence of cell-cell interactions. Moreover, these SMCs with YAP-linked mechanosensing showed higher expression of calponin, indicating a shift toward contractile phenotypes in vitro and in vivo. Furthermore, it showed skeletal muscle cells has different mechanosensing and maturation mechanisms compared to SMCs, revealing muscle type-dependent different sensing of topological cues, and converting into maturation-associated signaling cascades. This study provides insights into the regulation of SMC mechanotransduction and maturation by topological cues, suggesting the involvement of YAP-linked signaling pathways in this process.

Activation of nuclear receptor pregnane-X-receptor protects against abdominal aortic aneurysm by inhibiting oxidative stress.

Abdominal aortic aneurysm (AAA) is a life-threatening condition, but effective medications to prevent its progression and rupture are currently lacking. The nuclear receptor pregnane-X-receptor (PXR) plays a crucial role in vascular homeostasis. However, the role of PXR in AAA development remains unknown. We first detected the PXR expression in human and murine AAA tissues by RT-qPCR and Western blot. To investigate the potential role of PXR in the development of AAA, we used adeno-associated virus-mediated overexpression of PXR and pharmacological activation of PXR by ginkgolide A (GA) in mouse AAA models induced by both angiotensin II (AngII) and calcium phosphate [Ca3(PO4)2]. The underlying mechanism was further explored using RNA-sequencing and molecular biological analyses. We found a significant decrease in both mRNA and protein levels of PXR in both human and murine aortic smooth muscle cells from AAA tissues, accompanied with phenotypic switching of vascular smooth muscle cell and increased oxidative stress. PXR overexpression in abdominal aortas and GA treatment successfully suppressed AAA formation in both mouse AAA models. RNA-sequencing data revealed that PXR activation inhibited gamma-aminobutyric acid type A receptor subunit alpha3 (GABRA3) expression. Additional mechanistic studies identified that PXR suppressed AAA through mitigating GABRA3-induced reactive oxygen species (ROS) generation and subsequent phosphorylation of c-Jun N-terminal kinase (JNK). Interestingly, p-JNK was found to induce ubiquitin-proteasome degradation of PXR. In summary, our data unveiled, for the first time, the protective role of PXR against AAA pathogenesis by inhibiting oxidative stress. These findings suggested PXR as a promising therapeutic target for AAA.

3D spheroids versus 2D-cultured human adipose stem cells to generate smooth muscle cells in an internal anal sphincter-targeting cryoinjured mouse model.

BACKGROUND: The efficacy of cell implantation via 3D-spheroids to treat basal tone in fecal incontinence remains unclear. To address this, in this study, we aimed to identify cell differentiation and assess the development of a contractile phenotype corresponding to smooth muscle cells (SMCs) following implantation of 3D-spheroid and 2D-cultured human adipose stem cells (hASCs) in an in vivo internal anal sphincter (IAS)-targeted mouse model. METHODS: We developed an IAS-targeted in vivo model via rapid freezing (at - 196 °C) of the dorsal layers of the region of interest (ROI) of the IAS ring posterior quarter, between the submucosal and muscular layers, following submucosal dissection (n = 60 rats). After implantation of tetramethylindocarbocyanine perchlorate (Dil)-stained 3D and 2D-cells into randomly allocated cryoinjured rats, the entire sphincter ring or only the cryoinjured ROI was harvested. Expression of SMC markers, RhoA/ROCKII and its downstream molecules, and fibrosis markers was analyzed. Dil, α-smooth muscle actin (α-SMA), and RhoA signals were used for cell tracking. RESULTS: In vitro, 3D-spheroids exhibited higher levels of SMC markers and RhoA/ROCKII-downstream molecules than 2D-hASCs. The IAS-targeted cryoinjured model exhibited substantial loss of SMC layers of the squamous epithelium lining of the anal canal, as well as reduced expression of SMC markers and RhoA-related downstream molecules. In vivo, 3D-spheroid implantation induced SMC markers and contractile molecules weakly at 1 week. At 2 weeks, the mRNA expression of aSma, Sm22a, Smoothelin, RhoA, Mypt1, Mlc20, Cpi17, and Pp1cd increased, whereas that of fibrosis markers reduced significantly in the 3D-spheroid implanted group compared to those in the sham, non-implanted, and 2D-hASC implanted groups. Protein levels of RhoA, p-MYPT1, and p-MLC20 were higher in the 3D-spheroid-implanted group than in the other groups. At 2 weeks, in the implanted groups, the cryoinjured tissues (which exhibited Dil, α-SMA, and RhoA signals) were restored, while they remained defective in the sham and non-implanted groups. CONCLUSIONS: These findings demonstrate that, compared to 2D-cultured hASCs, 3D-spheroids more effectively induce a contractile phenotype that is initially weak but subsequently improves, inducing expression of RhoA/ROCKII-downstream molecules and SMC differentiation associated with IAS basal tone.

The role of 6-phosphogluconate dehydrogenase in vascular smooth muscle cell phenotypic switching and angioplasty-induced intimal hyperplasia.

Background: Restenosis poses a significant challenge for individuals afflicted with peripheral artery diseases, often leading to considerable morbidity and necessitating repeated interventions. The primary culprit behind the pathogenesis of restenosis is intimal hyperplasia (IH), in which the hyperproliferative and migratory vascular smooth muscle cell (VSMC) accumulate excessively in the tunica intima. 6-Phosphogluconate dehydrogenase (6PGD), sometimes referred to as PGD, is one of the critical enzymes in pentose phosphate pathway (PPP). In this study, we sought to probe whether 6PGD is aberrantly regulated in IH and contributes to VSMC phenotypic switching. Methods: We used clinical specimens of diseased human coronary arteries with IH lesions and observed robust upregulation of 6PGD at protein level in both the medial and intimal layers in comparison with healthy arterial segments. Results: 6PGD activity and protein expression were profoundly stimulated upon platelet-derived growth factor-induced VSMC phenotypic switching. Using gain-of-function (dCas9-mediated transcriptional activation) and loss-of-function (small interfering RNA-mediated) silencing, we were able to demonstrate the pathogenic role of 6PGD in driving VSMC hyperproliferation, migration, dedifferentiation, and inflammation. Finally, we conducted a rat model of balloon angioplasty in the common carotid artery, with Pluronic hydrogel-assisted perivascular delivery of Physcion, a selective 6PGD inhibitor with poor systemic bioavailability, and observed effective mitigation of IH. Conclusions: We contend that aberrant 6PGD expression and activity-indicative of a metabolic shift toward pentose phosphate pathway-could serve as a new disease-driving mechanism and, hence, an actionable target for the development of effective new therapies for IH and restenosis after endovascular interventions.

[Effects of inhibition of Rho/ROCK pathway on proliferation and migration of airway smooth muscle cells and related mechanisms]. / 抑制Rho/ROCKé€šè·¯å¯¹æ°”é“å¹³æ»‘è‚Œç»†èƒžå¢žæ®–ä¸Žè¿ç§»çš„å½±å“åŠç›¸å ³æœºåˆ¶.

OBJECTIVES: To investigate the effects and molecular mechanisms of inhibition of the Ras homolog gene (Rho)/Rho-associated coiled-coil forming protein kinase (ROCK) pathway on the proliferation and migration of airway smooth muscle cells involving myocardin (MYOCD). METHODS: Human airway smooth muscle cells were infected with the adenoviral vector Ad-ZsGreen-shRNA-hROCK1 in vitro. The cells were randomly divided into four groups: ROCK1 gene silencing control (shNC) group, shNC + arachidonic acid (AA, Rho/ROCK pathway activator) group, ROCK1 gene silencing (shROCK1) group, and shROCK1 + AA group (n=3 each). Quantitative real-time polymerase chain reaction and Western blot were used to detect the expression levels of ROCK1 and MYOCD mRNA and protein. ELISA was employed to measure the levels of globular actin and filamentous actin, while immunofluorescent staining and scratch assays were utilized to assess cell proliferation and migration. RESULTS: Compared to the shNC + AA group, the shROCK1 + AA group exhibited decreased levels of ROCK1 and MYOCD mRNA and protein expression, reduced expression levels of globular actin and filamentous actin, and diminished cell proliferation and migration capabilities (P<0.05). CONCLUSIONS: Inhibition of the Rho/ROCK pathway suppresses the proliferation and migration of airway smooth muscle cells, which may be associated with the downregulation of MYOCD.

Endoplasmic reticulum stress in abdominal aortic aneurysm.

Abdominal aortic aneurysms (AAAs) are characterized by permanent dilatation of the abdominal aorta, which is accompanied by inflammation, degradation of the extracellular matrix (ECM) and disruption of vascular smooth muscle cell (VSMC) homeostasis. Endoplasmic reticulum (ER) stress is involved in the regulation of inflammation, oxidative stress and VSMC apoptosis, all of which are critical factors in AAA development. Although several studies have revealed the occurrence of ER stress in AAA development, the specific biological functions of ER stress in AAA development remain largely unknown. Given that targeting ER stress is a promising strategy for treating AAAs, further investigation of the physiological and pathological roles of ER stress in AAA development is warranted.

ACE2 deficiency inhibits thoracic aortic dissection by enhancing SIRT3 mediated inhibition of inflammation and VSCMs phenotypic switch.

BACKGROUND: Thoracic aortic dissection (TAD) is an irreversible cardiovascular disorder with high mortality and morbidity. However, the molecular mechanisms remain elusive. Thus, identifying an effective therapeutic target to prevent TAD is especially critical. The purpose of this study is to elucidate the potential mechanism of inflammation and vascular smooth muscle cell (VSMCs) phenotypic switch in ß-aminopropionitrile fumarate (BAPN)-induced TAD. METHODS: A mouse model of TAD induced by BAPN and IL-1ß -stimulated HVSMCs in vivo and in vitro models, respectively. ACE2 Knockdown mice treated with BAPN or without, and the TAD mouse model was treated with or without AAV-ACE2. Transthoracic ultrasound was conducted for assessment the maximum internal diameter of the thoracic aorta arch. RNA sequencing analysis was performed to recapitulate transcriptome profile changes. Western blot were used to detect the expression of MMP2, MMP9, ACE2, SIRT3, OPN, SM22α and other inflammatory markers. The circulating levels of ACE2 was measured by ELISA assay. Histological changes of thoracic aorta tissues were assessed by H&E, EVG and IHC analysis. RESULTS: We found that circulating levels of and the protein levels of ACE2 were increased in the TAD mouse model and in patients with TAD. For further evidence, ACE2 deficiency decelerated the formation of TAD. However, overexpression of ACE2 aggravated BAPN-induced aortic injury and VSMCs phenotypic switch via lowered SIRT3 expression and elevated inflammatory cytokine expression. CONCLUSION: ACE2 deficiency prevented the development of TAD by inhibiting inflammation and VSMCs phenotypic switch in a SIRT3-dependent manner, suggesting that the ACE2/SIRT3 signaling pathway played a pivotal role in the pathological process of TAD and might be a potential therapeutical target.

lncRNA H19 facilitates vascular neointima formation by targeting miR-125a-3p/FLT1 axis.

The aberrant proliferation and migration of vascular smooth muscle cells (VSMCs) contribute to the development of neointima formation in vascular restenosis. This study aims to explore the function of the long noncoding RNA H19 in neointima formation. A mouse carotid ligation model was established, and human vascular smooth muscle cells (VSMCs) were used as a cell model. lncRNA H19 overexpression promoted VSMC proliferation and migration. Moreover, miR-125a-3p potentially bound to lncRNA H19, and Fms-like tyrosine kinase-1 (FLT1) might be a direct target of miR-125a-3p in VSMCs. Upregulation of miR-125a-3p alleviated lncRNA H19-enhanced VSMC proliferation and migration. Furthermore, rescue experiments showed that enhanced expression of miR-125a-3p attenuated lncRNA H19-induced FLT1 expression in VSMCs. In addition, the overexpression of lncRNA H19 significantly exacerbated neointima formation in a mouse carotid ligation model. In summary, lncRNA H19 stimulates VSMC proliferation and migration by acting as a competing endogenous RNA (ceRNA) of miR-125a-3p. lncRNA H19 may be a therapeutic target for restenosis.

In Vitro Models of Cardiovascular Calcification.

Cardiovascular calcification, characterized by hydroxyapatite deposition in the arterial wall and heart valves, is associated with high cardiovascular morbidity and mortality. Cardiovascular calcification is a hallmark of aging but is frequently seen in association with chronic diseases, such as chronic kidney disease (CKD), diabetes, dyslipidemia, and hypertension in the younger population as well. Currently, there is no therapeutic approach to prevent or cure cardiovascular calcification. The pathophysiology of cardiovascular calcification is highly complex and involves osteogenic differentiation of various cell types of the cardiovascular system, such as vascular smooth muscle cells and valve interstitial cells. In vitro cellular and ex vivo tissue culture models are simple and useful tools in cardiovascular calcification research. These models contributed largely to the discoveries of the numerous calcification inducers, inhibitors, and molecular mechanisms. In this review, we provide an overview of the in vitro cell culture and the ex vivo tissue culture models applied in the research of cardiovascular calcification.

Molecular basis of CX-5461-induced DNA damage response in primary vascular smooth muscle cells.

Our previous studies have shown that the novel selective RNA polymerase I inhibitor CX-5461 suppresses proliferation of vascular smooth muscle cells, mainly by inducing DNA damage response (DDR), including activations of ataxia telangiectasia mutated (ATM)/ATM and Rad3-related (ATR) and p53. Currently, there is no information about the molecular mechanism(s) underlying CX-5461-induced DDR in vascular cells, while the results obtained in cancer cells and immortalized cell lines are controversial. In this study, we examined the responses of various DDR pathways to CX-5461 treatment in primary aortic smooth muscle cells isolated from normal adult Sprague Dawley rats. We demonstrated that CX-5461-induced DDR was not associated with activations of the nucleotide excision repair, DNA mismatch repair, or the non-homologous end joining pathways, while the homologous recombination pathway was activated. However, the alkaline comet assay did not show massive DNA double strand breaks in CX-5461-treated cells. Instead, CX-5461-induced DDR appeared to be related to induction of DNA replication stress, which was not attributable to increased formation of G-quadruplex or R-loop structures, but might be explained by the increased replication-transcription conflict. CX-5461-induced DDR was not exclusively confined to rDNA within the nucleolar compartment; the extra-nucleolar DDR might represent a distinct secondary response related to the downregulated Rad51 expression in CX-5461-treated cells. In summary, we suggest that DNA replication stress may be the primary molecular event leading to downstream ATM/ATR and p53 activations in CX-5461-treated vascular smooth muscle cells. Our results provide further insights into the molecular basis of the beneficial effects of CX-5461 in proliferative vascular diseases.

Functional outcome of the anterior vaginal wall in a pelvic surgery injury rat model after treatment with stem cell-derived progenitors of smooth muscle cells.

BACKGROUND: Stem-cell-derived therapy is a promising option for tissue regeneration. Human iPSC-derived progenitors of smooth muscle cells (pSMCs) exhibit limited proliferation and differentiation, which minimizes the risk of tumor formation while restoring smooth muscle cells (SMCs). Up to 29% of women suffer from recurrence of vaginal prolapse after prolapse surgery. Therefore, there is a need for therapies that can restore vaginal function. SMCs contribute to vaginal tone and contractility. We sought to examine whether human pSMCs can restore vaginal function in a rat model. METHODS: Female immunocompromised RNU rats were divided into 5 groups: intact controls (n = 12), VSHAM (surgery + saline injection, n = 35), and three cell-injection groups (surgery + cell injection using pSMCs from three patients, n = 14/cell line). The surgery to induce vaginal injury was analogous to prolapse surgery. Menopause was induced by surgical ovariectomy. The vagina, urethra, bladder were harvested 10 weeks after surgery (5 weeks after cell injection). Organ bath myography was performed to evaluate the contractile function of the vagina, and smooth muscle thickness was examined by tissue immunohistochemistry. Collagen I, collagen III, and elastin mRNA and protein expressions in tissues were assessed. RESULTS: Vaginal smooth muscle contractions induced by carbachol and KCl in the cell-injection groups were significantly greater than those in the VSHAM group. Collagen I protein expression in the vagina of the cell-injections groups was significantly higher than in the VSHAM group. Vaginal elastin protein expression was similar between the cell-injection and VSHAM groups. In the urethra, gene expression levels of collagen I, III, and elastin were all significantly greater in the cell-injection groups than in the VSHAM group. Collagen I, III, and elastin protein expression of the urethra did not show a consistent trend between cell-injection groups and the VSHAM group. CONCLUSIONS: Human iPSC-derived pSMCs transplantation appears to be associated with improved contractile function of the surgically injured vagina in a rat model. This is accompanied by changes in extracellular protein expression the vagina and urethra. These observations support further efforts in the translation of pSMCs into a treatment for regenerating the surgically injured vagina in women who suffer recurrent prolapse after surgery.

Podocan unraveled: Understanding its role in tumor proliferation and smooth muscle regulation.

Podocan, a small leucine-rich repeat protein, is expressed in HIV-associated nephropathy, the cardiovascular system, and smooth muscle. Studies have linked PODN and PODNL to cancers such as osteosarcoma, glioma, and stomach cancer. Research has primarily focused on podocan's role in renal podocytes, injured smooth muscle cells, and various tumor cells. Bioinformatics studies have examined the role of PODN as a biomarker in tumors. Our research summarizes the modulatory role of podocan in smooth muscle and tumor proliferation through its suppression of cell proliferation and promotion of cell differentiation via various signaling pathways, including Wnt/ß-catenin, TGF-ß, and Akt/mTOR. We aim to provide a comprehensive overview of PODN's involvement in smooth muscle, cardiovascular system, and tumors by integrating current and past research. This review aims to enhance understanding and inform in the diagnosis, prognosis, and treatment of various diseases.

NONRATT000538.2 promotes vascular smooth muscle cell phenotypic switch and in-stent restenosis.

Vascular smooth muscle cell (VSMC) excessive proliferation and migration are considered the main pathological process in in-stent restenosis (ISR) following vascular intervention. Certain long noncoding RNAs play vital roles in this process. Therefore, this study aimed to explore novel regulators for ISR and further uncover the mechanism. Using a rat abdominal aorta stent implantation model, we observed that NONRATT000538.2 (NR538.2) served as a positive regulator for VSMC proliferation and migration. By manipulating NR538.2 expression via adenoviral overexpression or siRNA knockdown, we noted that NR538.2 promoted VSMC phenotypic switching, thereby inducing proliferation and migration. Significantly, the local delivery of siRNA of NR538.2 via adeno-associated virus vector suppressed balloon injury-induced neointima formation. Our study demonstrated for the first time that NR538.2 positively influenced VSMC proliferation during ISR.

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.

ß-sitosterol alleviates pulmonary arterial hypertension by altering smooth muscle cell phenotype and DNA damage/cGAS/STING signaling.

BACKGROUND: Pulmonary arterial smooth muscle cells (PASMCs) have a neoplastic phenotype characterized by hyperproliferative and anti-apoptotic features that contribute to pulmonary hypertension (PH) development. DNA-sensing adapter protein stimulator of interferon genes (STING) regulate the phenotypic switch of vessel smooth muscle cells. ß-sitosterol (SITO) is a nutrient derived from plants that inhibits vascular smooth muscle cell proliferation without notable toxicity. However, the effect of SITO on cancer-like PH-associated pulmonary vascular remodeling and the specific mechanism has not yet be studied. PURPOSE: This study investigated the in vitro and in vivo effects of SITO against PH, and its underlying mechanisms. METHODS: The therapeutic efficacy of SITO was assessed, and its underlying mechanisms were explored in hypoxia-induced and platelet-derived growth factor (PDGF)-BB-stimulated primary PASMCs and in a monocrotaline (MCT)-induced preclinical PH rat model. SITO or sildenafil (SID) were administered after the MCT intraperitoneal injection. Pulmonary parameters, right heart function, morphology, and PASMCs were cultured for verification. The expression levels of DNA damage/cyclic GMP-AMP synthase (cGAS)/STING were determined using immunofluorescence and Western blotting. STING agonists that interfere with PASMCs were used to determine whether STING mediates the effects of SITO. RESULTS: SITO prevented PASMCs proliferation, promoted apoptosis and suppressed phenotypic switching in a dose-dependent manner in vitro and in vivo. In vivo results in rats demonstrated that four weeks of intragastric SITO administration effectively mitigated the MCT-induced elevation of hemodynamic parameters, improved right cardiac function, and reduced pulmonary arteries remodeling. Mechanistically, DNA damage and cGAS/STING/nuclear factor kappa-B signaling activation were observed in rats with PH and cultured PASMCs. SITO exhibited protective effects by suppressing the DNA damage, potentially via inhibiting the expression level of the cGAS/STING signaling pathway. Pharmacological overexpression of STING abolished the anti-proliferative effects of SITO treatment in hypoxia-induced and PDGF-stimulated PASMCs by downregulating PCNA. CONCLUSION: SITO may be an attractive agent for PH vascular remodeling by inhibiting proliferation and modulating the phenotypic switch in PASMCs via the DNA damage/cGAS/STING signaling pathway. This study provides a novel therapeutic agent and mediator of the pathological development of PASMCs and PH.

Mechanotransduction of the vasculature in Hutchinson-Gilford Progeria Syndrome.

Hutchinson-Gilford Progeria Syndrome (HGPS) is a premature aging disorder that causes severe cardiovascular disease, resulting in the death of patients in their teenage years. The disease pathology is caused by the accumulation of progerin, a mutated form of the nuclear lamina protein, lamin A. Progerin binds to the inner nuclear membrane, disrupting nuclear integrity, and causes severe nuclear abnormalities and changes in gene expression. This results in increased cellular inflammation, senescence, and overall dysfunction. The molecular mechanisms by which progerin induces the disease pathology are not fully understood. Progerin's detrimental impact on nuclear mechanics and the role of the nucleus as a mechanosensor suggests dysfunctional mechanotransduction could play a role in HGPS. This is especially relevant in cells exposed to dynamic, continuous mechanical stimuli, like those of the vasculature. The endothelial (ECs) and smooth muscle cells (SMCs) within arteries rely on physical forces produced by blood flow to maintain function and homeostasis. Certain regions within arteries produce disturbed flow, leading to an impaired transduction of mechanical signals, and a reduction in cellular function, which also occurs in HGPS. In this review, we discuss the mechanics of nuclear mechanotransduction, how this is disrupted in HGPS, and what effect this has on cell health and function. We also address healthy responses of ECs and SMCs to physiological mechanical stimuli and how these responses are impaired by progerin accumulation.