Long non-coding RNAs in drug resistance across the top five cancers: Update on their roles and mechanisms.

Cancer drug resistance stands as a formidable obstacle in the relentless fight against the top five prevalent cancers: breast, lung, colorectal, prostate, and gastric cancers. These malignancies collectively account for a significant portion of cancer-related deaths worldwide. In recent years, long non-coding RNAs (lncRNAs) have emerged as pivotal players in the intricate landscape of cancer biology, and their roles in driving drug resistance are steadily coming to light. This comprehensive review seeks to underscore the paramount significance of lncRNAs in orchestrating resistance across a spectrum of different cancer drugs, including platinum drugs (DDP), tamoxifen, trastuzumab, 5-fluorouracil (5-FU), paclitaxel (PTX), and Androgen Deprivation Therapy (ADT) across the most prevalent types of cancer. It delves into the multifaceted mechanisms through which lncRNAs exert their influence on drug resistance, shedding light on their regulatory roles in various facets of cancer biology. A comprehensive understanding of these lncRNA-mediated mechanisms may pave the way for more effective and personalized treatment strategies, ultimately improving patient outcomes in these challenging malignancies.

CD73/adenosine axis exerts cardioprotection against hypobaric hypoxia-induced metabolic shift and myocarditis in a sex-dependent manner.

BACKGROUND: Clinical and experimental studies have shown that the myocardial inflammatory response during pathological events varies between males and females. However, the cellular and molecular mechanisms of these sex differences remain elusive. CD73/adenosine axis has been linked to anti-inflammatory responses, but its sex-specific cardioprotective role is unclear. The present study aimed to investigate whether the CD73/adenosine axis elicits sex-dependent cardioprotection during metabolic changes and myocarditis induced by hypobaric hypoxia. METHODS: For 7 days, male and female mice received daily injections of the CD73 inhibitor adenosine 5'- (α, ß-methylene) diphosphate (APCP) 10 mg/kg/day while they were kept under normobaric normoxic and hypobaric hypoxic conditions. We evaluated the effects of hypobaric hypoxia on the CD73/adenosine axis, myocardial hypertrophy, and cardiac electrical activity and function. In addition, metabolic homeostasis and immunoregulation were investigated to clarify the sex-dependent cardioprotection of the CD73/adenosine axis. RESULTS: Hypobaric hypoxia-induced cardiac dysfunction and adverse remodeling were more pronounced in male mice. Also, male mice had hyperactivity of the CD73/adenosine axis, which aggravated myocarditis and metabolic shift compared to female mice. In addition, CD73 inhibition triggered prostatic acid phosphatase ectonucleotidase enzymatic activity to sustain adenosine overproduction in male mice but not in female mice. Moreover, dual inhibition prostatic acid phosphatase and CD73 enzymatic activities in male mice moderated adenosine content, alleviating glycolytic shift and proinflammatory response. CONCLUSION: The CD73/adenosine axis confers a sex-dependent cardioprotection. In addition, extracellular adenosine production in the hearts of male mice is influenced by prostatic acid phosphatase and tissue nonspecific alkaline phosphatase.

Ischemia-reperfusion injury: molecular mechanisms and therapeutic targets.

Ischemia-reperfusion (I/R) injury paradoxically occurs during reperfusion following ischemia, exacerbating the initial tissue damage. The limited understanding of the intricate mechanisms underlying I/R injury hinders the development of effective therapeutic interventions. The Wnt signaling pathway exhibits extensive crosstalk with various other pathways, forming a network system of signaling pathways involved in I/R injury. This review article elucidates the underlying mechanisms involved in Wnt signaling, as well as the complex interplay between Wnt and other pathways, including Notch, phosphatidylinositol 3-kinase/protein kinase B, transforming growth factor-ß, nuclear factor kappa, bone morphogenetic protein, N-methyl-D-aspartic acid receptor-Ca2+-Activin A, Hippo-Yes-associated protein, toll-like receptor 4/toll-interleukine-1 receptor domain-containing adapter-inducing interferon-ß, and hepatocyte growth factor/mesenchymal-epithelial transition factor. In particular, we delve into their respective contributions to key pathological processes, including apoptosis, the inflammatory response, oxidative stress, extracellular matrix remodeling, angiogenesis, cell hypertrophy, fibrosis, ferroptosis, neurogenesis, and blood-brain barrier damage during I/R injury. Our comprehensive analysis of the mechanisms involved in Wnt signaling during I/R reveals that activation of the canonical Wnt pathway promotes organ recovery, while activation of the non-canonical Wnt pathways exacerbates injury. Moreover, we explore novel therapeutic approaches based on these mechanistic findings, incorporating evidence from animal experiments, current standards, and clinical trials. The objective of this review is to provide deeper insights into the roles of Wnt and its crosstalk signaling pathways in I/R-mediated processes and organ dysfunction, to facilitate the development of innovative therapeutic agents for I/R injury.

Unlocking the predictive potential of long non-coding RNAs: a machine learning approach for precise cancer patient prognosis.

The intricate web of cancer biology is governed by the active participation of long non-coding RNAs (lncRNAs), playing crucial roles in cancer cells' proliferation, migration, and drug resistance. Pioneering research driven by machine learning algorithms has unveiled the profound ability of specific combinations of lncRNAs to predict the prognosis of cancer patients. These findings highlight the transformative potential of lncRNAs as powerful therapeutic targets and prognostic markers. In this comprehensive review, we meticulously examined the landscape of lncRNAs in predicting the prognosis of the top five cancers and other malignancies, aiming to provide a compelling reference for future research endeavours. Leveraging the power of machine learning techniques, we explored the predictive capabilities of diverse lncRNA combinations, revealing their unprecedented potential to accurately determine patient outcomes.

lncRNAs play crucial roles in cancer biology, regulating proliferation, migration, and drug resistance.Emerging evidence suggests that machine learning can predict cancer prognosis using specific lncRNA combinations.Comprehensive information on the predictive abilities of lncRNA combinations in oncology concerning machine learning is lacking.This review offers up-to-date vital references on diverse lncRNA combinations pertinent to future research and clinical trials.

p53 contributes to cardiovascular diseases via mitochondria dysfunction: A new paradigm.

Cardiovascular diseases (CVDs) are leading causes of global mortality; however, their underlying mechanisms remain unclear. The tumor suppressor factor p53 has been extensively studied for its role in cancer and is also known to play an important role in regulating CVDs. Abnormal p53 expression levels and modifications contribute to the occurrence and development of CVDs. Additionally, mounting evidence underscores the critical involvement of mitochondrial dysfunction in CVDs. Notably, studies indicate that p53 abnormalities directly correlate with mitochondrial dysfunction and may even interact with each other. Encouragingly, small molecule inhibitors targeting p53 have exhibited remarkable effects in animal models of CVDs. Moreover, therapeutic strategies aimed at mitochondrial-related molecules and mitochondrial replacement therapy have demonstrated their advantageous potential. Therefore, targeting p53 or mitochondria holds immense promise as a pioneering therapeutic approach for combating CVDs. In this comprehensive review, we delve into the mechanisms how p53 influences mitochondrial dysfunction, including energy metabolism, mitochondrial oxidative stress, mitochondria-induced apoptosis, mitochondrial autophagy, and mitochondrial dynamics, in various CVDs. Furthermore, we summarize and discuss the potential significance of targeting p53 or mitochondria in the treatment of CVDs.

Estradiol mitigates stress-induced cardiac injury and inflammation by downregulating ADAM17 via the GPER-1/PI3K signaling pathway.

Stress-induced cardiovascular diseases characterized by inflammation are among the leading causes of morbidity and mortality in postmenopausal women worldwide. Estradiol (E2) is known to be cardioprotective via the modulation of inflammatory mediators during stress. But the mechanism is unclear. TNFα, a key player in inflammation, is primarily converted to its active form by 'A Disintegrin and Metalloprotease 17' (ADAM17). We investigated if E2 can regulate ADAM17 during stress. Experiments were performed using female FVB wild-type (WT), C57BL/6 WT, and G protein-coupled estrogen receptor 1 knockout (GPER-1 KO) mice and H9c2 cells. The study revealed a significant increase in cardiac injury and inflammation during isoproterenol (ISO)-induced stress in ovariectomized (OVX) mice. Additionally, ADAM17's membrane content (mADAM17) was remarkably increased in OVX and GPER-1 KO mice during stress. However, in vivo supplementation of E2 significantly reduced cardiac injury, mADAM17, and inflammation. Also, administering G1 (GPER-1 agonist) in mice under stress reduced mADAM17. Further experiments demonstrated that E2, via GPER-1/PI3K pathway, localized ADAM17 at the perinuclear region by normalizing ß1AR-Gαs, mediating the switch from ß2AR-Gαi to Gαs, and reducing phosphorylated kinases, including p38 MAPKs and ERKs. Thus, using G15 and LY294002 to inhibit GPER-1 and its down signaling molecule, PI3K, respectively, in the presence of E2 during stress resulted in the disappearance of E2's modulatory effect on mADAM17. In vitro knockdown of ADAM17 during stress significantly reduced cardiac injury and inflammation, confirming its significant inflammatory role. These interesting findings provide novel evidence that E2 and G1 are potential therapeutic agents for ADAM17-induced inflammatory diseases associated with postmenopausal females.

Sodium houttuyfonate against cardiac fibrosis attenuates isoproterenol-induced heart failure by binding to MMP2 and p38.

BACKGROUND: Heart failure (HF), caused by stress cardiomyopathy, is a major cause of mortality. Cardiac fibrosis is an essential structural remodeling associated with HF; therefore, preventing cardiac fibrosis is crucial to decelerating the progression of HF. Sodium houttuyfonate (SH), an extract of Houttuynia cordata, has a potent therapeutic effect on hypoxic cardiomyocytes in a myocardial infarction model. PURPOSE: To investigate the preventative and therapeutic effects of SH during isoproterenol (ISO)-induced HF and explore the pharmacological mechanism of SH in alleviating HF. METHODS: We analyzed the overlapping target genes between SH and cardiac fibrosis or HF using a network pharmacology analytical method. We verified the suppressive effect of SH on ISO-induced proliferation and activation of cardiac fibroblasts by immunohistochemical staining and histological analysis in an isoproterenol-induced HF mouse model. Additionally, we investigated the effect of SH by evaluating fibrosis and cardiac remodeling markers. To further decipher the pharmacological mechanism of SH against cardiac fibrosis and HF, we performed a molecular docking analysis between SH and hub common target genes. RESULTS: There were 20 overlapping target genes between SH and cardiac fibrosis and 32 overlapping target genes between SH and HF. The 16 common target genes of SH against cardiac fibrosis and HF included MMP2 (matrix metalloproteinase 2), and p38. SH significantly inhibited the ISO- or TGF-ß-induced expression of Col1α (collagen 1), α-SMA (smooth muscle actin), MMP2, TIMP2 (tissue inhibitor of metalloproteinase 2), TGF-ß (transforming growth factor), and Smad2 phosphorylation. Moreover, both ISO- and TGF-ß-induced p38 phosphorylation was inhibited. Molecular docking analysis showed that SH forms a stable complex with MMP2 and p38. CONCLUSIONS: In addition to protecting cardiomyocytes, SH directly inhibits cardiac fibroblast activation and proliferation by binding to MMP2 and p38, subsequently delaying cardiac fibrosis and HF progression. Our prevention- and intervention-based approaches in this study showed that SH inhibited the development of stress cardiomyopathy-mediated cardiac fibrosis and HF when SH was administered before or after the initiation of cardiac stress.

CXCR6 Mediates Pressure Overload-Induced Aortic Stiffness by Increasing Macrophage Recruitment and Reducing Exosome-miRNA29b.

Aortic stiffness is an independent risk factor for aortic diseases such as aortic dissection which commonly occurred with aging and hypertension. Chemokine receptor CXCR6 is critically involved in vascular inflammation and remodeling. Here, we investigated whether and how CXCR6 plays a role in aortic stiffness caused by pressure overload. CXCR6-/- and WT mice underwent transverse aortic constriction (TAC) surgery for 8 weeks. CXCR6 deficiency significantly improved TAC-induced aortic remodeling and endothelial dysfunction by decreasing CD11c+ macrophage infiltration, suppressing VCAM-1 and ICAM-1, reducing collagen deposition, and downregulating MMP12 and osteopontin in the aorta. Consistently, blocking the CXCL16/CXCR6 axis also reduced aortic accumulation of CD11c+ macrophages and vascular stiffness but without affecting the release of TNF-α and IL-6 from the aorta. Furthermore, pressure overload inhibited aortic release of exosomes, which could be reversed by suppressing CXCR6 or CXCL16. Inhibition of exosome release by GW4869 significantly aggravated TAC-induced aortic calcification and stiffness. By exosomal microRNA microarray analysis, we found that microRNA-29b was significantly reduced in aortic endothelial cells (AECs) receiving TAC. Intriguingly, blocking the CXCL16/CXCR6 axis restored the expression of miR-29b in AECs. Finally, overexpression of miR-29b significantly increased eNOS and reduced MMPs and collagen in AECs. By contrast, antagonizing miR-29b in vivo further enhanced TAC-induced expressions of MMP12 and osteopontin, aggravated aortic fibrosis, calcification, and stiffness. Our study demonstrated a key role of the CXCL16/CXCR6 axis in macrophage recruitment and macrophage-mediated aortic stiffness under pressure overload through an exosome-miRNAs-dependent manner.

Novel hub genes associated with pulmonary artery remodeling in pulmonary hypertension.

Pulmonary hypertension (PH) is a life-threatening disease with complex pathogenesis. According to etiology, PH is divided into five major groups in clinical classification. However, pulmonary artery (PA) remodeling is their common feature, in addition to bone morphogenetic protein receptor type 2; it is elusive whether there are other novel common genes and similar underlying mechanisms. To identify novel common hub genes involved in PA remodeling at different PH groups, we analyzed mRNA-Seq data located in the general gene expression profile GSE130391 utilizing bioinformatics technology. This database contains PA samples from different PH groups of hospitalized patients with chronic thromboembolic pulmonary hypertension (CTEPH), idiopathic pulmonary artery hypertension (IPAH), and PA samples from organ donors without known pulmonary vascular diseases as control. We screened 22 hub genes that affect PA remodeling, most of which have not been reported in PH. We verified the top 10 common hub genes in hypoxia with Sugen-induced PAH rat models by qRT-PCR. The three upregulated candidate genes are WASF1, ARHGEF1 and RB1 and the seven downregulated candidate genes are IL1R1, RHOB, DAPK1, TNFAIP6, PKN1, PLOD2, and MYOF. WASF1, ARHGEF1, and RB1 were upregulated significantly in hypoxia with Sugen-induced PAH, while IL1R1, DAPK1, and TNFA1P6 were upregulated significantly in hypoxia with Sugen-induced PAH. The DEGs detected by mRNA-Seq in hospitalized patients with PH are different from those in animal models. This study will provide some novel target genes to further study PH mechanisms and treatment.

Applications and challenges of rhodopsin-based optogenetics in biomedicine.

Optogenetics is an emerging bioengineering technology that has been rapidly developed in recent years by cross-integrating optics, genetic engineering, electrophysiology, software control, and other disciplines. Since the first demonstration of the millisecond neuromodulation ability of the channelrhodopsin-2 (ChR2), the application of optogenetic technology in basic life science research has been rapidly progressed, especially in neurobiology, which has driven the development of the discipline. As the optogenetic tool protein, microbial rhodopsins have been continuously explored, modified, and optimized, with many variants becoming available, with structural characteristics and functions that are highly diversified. Their applicability has been broadened, encouraging more researchers and clinicians to utilize optogenetics technology in research. In this review, we summarize the species and variant types of the most important class of tool proteins in optogenetic techniques, the microbial rhodopsins, and review the current applications of optogenetics based on rhodopsin qualitative light in biology and other fields. We also review the challenges facing this technology, to ultimately provide an in-depth technical reference to support the application of optogenetics in translational and clinical research.

MiR-1249 on Endothelial Extracellular Vesicles Mediates Cigarette Smoke-Induced Pulmonary Hypertension by Inhibiting HDAC10 (Histone Deacetylase 10)-NFκB (Nuclear Factor κB)-CaSR (Calcium-Sensing Receptor) Cascade.

BACKGROUND: Overproduction of endothelial extracellular vesicles (eEVs) is correlated with pulmonary hypertension progression, but the precise mechanism remains largely unclear. METHODS: MicroRNA-chip and real-time polymerase chain reaction were conducted to screen and validate microRNA profiles in blood plasma eEVs of rats and human with or without cigarette smoking. Pulmonary artery smooth muscle cells were cultured to study signaling pathways. Pulmonary hypertension phenotypes were evaluated in wild-type and calcium-sensing receptor knockout rats to identify the pathophysiological significance of the microRNA pathway. RESULTS: MicroR-1249 was predominant highly expressed in eEVs from plasma of rats exposed to cigarette smoking, and confirmed in eEVs from plasma of human smokers as well as in eEVs from cigarette smoke extract-treated pulmonary artery endothelial cells, but not in cigarette smoke extract-treated pulmonary artery smooth muscle cells. In cultured pulmonary artery smooth muscle cells, microR-1249 downregulated the expression of histone deacetylase 10, which in turn enhanced the acetylated form of NFκB (nuclear factor κB) level and its nuclear translocation leading to increased expression of calcium-sensing receptor. In rats, the repression of microR-1249 in eEVs by microR-1249 inhibitor, histone deacetylase 10 overexpression, or calcium-sensing receptor knockout profoundly inhibited the proliferative capacities and diminished apoptosis-resistance of pulmonary artery smooth muscle cells and pulmonary hypertension development in rats intravenously administrated with eEVs preparation from cigarette smoke extract-treated pulmonary artery endothelial cells. CONCLUSIONS: Cigarette smoke-enriched microR-1249 in endothelial extracellular vesicles facilitates the hyperproliferative and antiapoptotic status of pulmonary artery smooth muscle cells promoting pulmonary hypertension evolution through the inhibition of histone deacetylase 10-NFκB-calcium-sensing receptor cascade.

Programmed Exercise Attenuates Familial Hypertrophic Cardiomyopathy in Transgenic E22K Mice via Inhibition of PKC-α/NFAT Pathway.

Familial hypertrophic cardiomyopathy (FHCM), an autosomal dominant disease, is caused by mutations in genes encoding cardiac sarcomeric proteins. E22K, a mutation in the myosin regulatory light chain sarcomere gene, is associated with the development of FHCM. However, the molecular mechanisms by which E22K mutation promotes septal hypertrophy are still elusive. The hypertrophic markers, including beta-myosin heavy chain, atrial natriuretic peptide and B-type natriuretic peptide, were upregulated, as detected by fluorescence quantitative PCR. The gene expression profiles were greatly altered in the left ventricle of E22K mutant mice. Among these genes, nuclear factor of activated T cells (NFAT) and protein kinase C-alpha (PKC-α) were upregulated, and their protein expression levels were also verified to be elevated. The fibrosis markers, such as phosphorylated Smad and transforming growth factor beta receptor, were also elevated in transgenic E22K mice. After receiving 6 weeks of procedural exercise training, the expression levels of PKC-α and NFAT were reversed in E22K mouse hearts. In addition, the expression levels of several fibrosis-related genes such as transforming growth factor beta receptor 1, Smad4, and alpha smooth muscle actin in E22K mouse hearts were also reversed. Genes that associated with cardiac remodeling such as myocyte enhancer factor 2C, extracellular matrix protein 2 and fibroblast growth factor 12 were reduced after exercising. Taken together, our results indicate that exercise can improve hypertrophy and fibrosis-related indices in transgenic E22K mice via PKC-α/NFAT pathway, which provide new insight into the prevention and treatment of familial hypertrophic cardiomyopathy.

Human-derived decellularized extracellular matrix scaffold incorporating autologous bone marrow stem cells from patients with congenital heart disease for cardiac tissue engineering.

BACKGROUND: Stem cells are used as an alternative treatment option for patients with congenital heart disease (CHD) due to their regenerative potential, but they are subject to low retention rate in the injured myocardium. Also, the diseased microenvironment in the injured myocardium may not provide healthy cues for optimal stem cell function. OBJECTIVE: In this study, we prepared a novel human-derived cardiac scaffold to improve the functional behaviors of stem cells. METHODS: Decellularized extracellular matrix (ECM) scaffolds were fabricated by removing cells of human-derived cardiac appendage tissues. Then, bone marrow c-kit+ progenitor cells from patients with congenital heart disease were seeded on the cardiac ECM scaffolds. Cell adhesion, survival, proliferation and cardiac differentiation on human cardiac decellularized ECM scaffold were evaluated in vitro. Label-free mass spectrometry was applied to analyze cardiac ECM proteins regulating cell behaviors. RESULTS: It was shown that cardiac ECM scaffolds promoted stem cell adhesion and proliferation. Importantly, bone marrow c-kit+ progenitor cells cultured on cardiac ECM scaffold for 14 days differentiated into cardiomyocyte-like cells without supplement with any inducible factors, as confirmed by the increased protein level of Gata4 and upregulated gene levels of Gata4, Nkx2.5, and cTnT. Proteomic analysis showed the proteins in cardiac ECM functioned in multiple biological activities, including regulation of cell proliferation, regulation of cell differentiation, and cardiovascular system development. CONCLUSION: The human-derived cardiac scaffold constructed in this study may help repair the damaged myocardium and hold great potential for tissue engineering application in pediatric patients with CHD.

Targeting JP2: A New Treatment for Pulmonary Hypertension.

Pulmonary hypertension (PH) is a disease with a complex etiology and high mortality rate. Abnormal pulmonary vasoconstriction and pulmonary vascular remodeling lead to an increase in mean pulmonary arterial blood pressure for which, and there is currently no cure. Junctophilin-2 (JP2) is beneficial for the assembly of junctional membrane complexes, the structural basis for excitation-contraction coupling that tethers the plasma membrane to the sarcoplasmic reticulum/endoplasmic reticulum and is involved in maintaining intracellular calcium concentration homeostasis and normal muscle contraction function. Recent studies have shown that JP2 maintains normal contraction and relaxation of vascular smooth muscle. In some experimental studies of drug treatments for PH, JP2 expression was increased, which improved pulmonary vascular remodeling and right ventricular function. Based on JP2 research to date, this paper summarizes the current understanding of JP2 protein structure, function, and related heart diseases and mechanisms and analyzes the feasibility and possible therapeutic strategies for targeting JP2 in PH.

Protein S-Palmitoylation and Lung Diseases.

S-palmitoylation of protein is a posttranslational, reversible lipid modification; it was catalyzed by a family of 23 mammalian palmitoyl acyltransferases in humans. S-palmitoylation can impact protein function by regulating protein sorting, secretion, trafficking, stability, and protein interaction. Thus, S-palmitoylation plays a crucial role in many human diseases including mental illness and cancers. In this chapter, we systematically reviewed the influence of S-palmitoylation on protein performance, the characteristics of S-palmitoylation regulating protein function, and the role of S-palmitoylation in pulmonary inflammation and pulmonary hypertension and summed up the treatment strategies of S-palmitoylation-related diseases and the research status of targeted S-palmitoylation agonists/inhibitors. In conclusion, we highlighted the potential role of S-palmitoylation and depalmitoylation in the treatment of human diseases.

p53: A Key Protein That Regulates Pulmonary Fibrosis.

Pulmonary fibrosis is a progressively aggravating lethal disease that is a serious public health concern. Although the incidence of this disease is increasing, there is a lack of effective therapies. In recent years, the pathogenesis of pulmonary fibrosis has become a research hotspot. p53 is a tumor suppressor gene with crucial roles in cell cycle, apoptosis, tumorigenesis, and malignant transformation. Previous studies on p53 have predominantly focused on its role in neoplastic disease. Following in-depth investigation, several studies have linked it to pulmonary fibrosis. This review covers the association between p53 and pulmonary fibrosis, with the aim of providing novel ideas to improve the clinical diagnosis, treatment, and prognosis of pulmonary fibrosis.

Phenylalanine induces pulmonary hypertension through calcium-sensing receptor activation.

Phenylalanine levels are associated with pulmonary hypertension in metabolic profiling clinical studies. However, the pathophysiological role of phenylalanine on pulmonary circulation is still unclear. We experimentally addressed the direct impact of phenylalanine on pulmonary circulation in rats and explored the underlying molecular pathway. Phenylalanine was injected intraperitoneally into Sprague-Dawley rats (400 mg/100 g body wt) as a single dose or daily in a chronic manner for 2, 3, and 4 wk. Chronic injection of phenylalanine induced pulmonary hypertension with time-dependent severity, evidenced by elevated pulmonary artery pressure and pulmonary vascular resistance as well as pulmonary artery and right ventricular hypertrophy. Using tandem mass spectrometry analysis, we found a quick twofold increase in blood level of phenylalanine 2 h following injection. This increase led to a significant accumulation of phenylalanine in lung after 4 h, which remained sustained at up to a threefold increase after 4 wk. In addition, a cellular thermal shift assay with lung tissues from phenylalanine-injected rats revealed the binding of phenylalanine to the calcium-sensing receptor (CaSR). In vitro experiments with cultured pulmonary arterial smooth muscle cells showed that phenylalanine activated CaSR, as indicated by an increase in intracellular calcium content, which was attenuated or diminished by the inhibition or knockdown of CaSR. Finally, the global knockout or lung-specific knockdown of CaSR significantly attenuated phenylalanine-induced pulmonary hypertension. Chronic phenylalanine injection induces pulmonary hypertension through binding to CaSR and its subsequent activation. Here, we demonstrate a pathophysiological role of phenylalanine in pulmonary hypertension through the CaSR. This study provides a novel animal model for pulmonary hypertension and reveals a potentially clinically significant role for this metabolite in human pulmonary hypertension as a marker, a mediator of disease, and a possible therapeutic target.

Therapeutic effectiveness of bone marrow-derived mesenchymal stem cell administration against acute pulmonary thromboembolism in a mouse model.

INSTRUCTION: Acute pulmonary thromboembolism (APTE) is a common clinical condition associated with significant morbidity and mortality. Although promising, bone marrow-derived mesenchymal stem cell (BMSC) treatment for thrombus resolution remains controversial. The therapeutic effectiveness of BMSC against APTE has not been evaluated. This study aims to determine whether BMSCs administration is effective in mouse model. MATERIALS AND METHODS: Therapeutic efficacy of female and male BMSCs were evaluated by applying serial sectioning analysis method for the whole lungs of APTE mice and calculating each thrombus size in volume. Plasmid construction and stable transfection were used to manipulate expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in both genders of BMSCs. Western blot were performed to detect GAPDH and urokinase plasminogen activator expression in BMSCs. RESULTS: Our data showed, 1) compared with non-serial sectioning method, the serial sectioning method detected more thrombi, larger size ranges of thrombus area, and the volume of each individual thrombus. 2) BMSCs significantly decreased the thrombi size in APTE mice, with female BMSCs superior to male ones. 3) female BMSCs showed a higher GAPDH protein level and manipulations of GAPDH expression in female or male BMSCs profoundly affected their therapeutic efficacies as well as urokinase plasminogen activator expression. CONCLUSION: This study indicates serial-sectioning analysis method is necessary for evaluating APTE and provides strong evidences for BMSCs possessing therapeutic effectiveness against APTE, with female BMSCs superior to male counterparts. GAPDH played a critical role in the superior function of female BMSCs, possibly by regulating the expression of urokinase plasminogen activator.

GAPDH is critical for superior efficacy of female bone marrow-derived mesenchymal stem cells on pulmonary hypertension.

AIMS: Pulmonary arterial hypertension, a chronic lung disease, remains an unacceptable prognosis despite significant advances in conventional therapies. Stem cell therapy represents a novel and effective modality. This study was aimed to add new insight in gender differences of bone marrow-derived mesenchymal stem cells on therapy against pulmonary arterial hypertension and the underlying mechanism. METHODS AND RESULTS: By in vivo experiments, we showed for the first time female bone marrow-derived mesenchymal stem cells possessed a better therapeutic potential against monocrotaline-induced pulmonary arterial hypertension in C57BL/6J mice compared with male counterparts. In vitro experiments demonstrated superior function of female bone marrow-derived mesenchymal stem cells in cell proliferation, migration and [Ca(2+)]i kinetics. Moreover, we unexpectedly found that, compared with male ones, female bone marrow-derived mesenchymal stem cells had a higher expression level of glyceraldehyde-3-phosphate dehydrogenase and manipulations of its expression in female or male bone marrow-derived mesenchymal stem cells profoundly affected their cellular behaviours and therapeutic efficacies against pulmonary arterial hypertension. CONCLUSION: Our results suggest that glyceraldehyde-3-phosphate dehydrogenase plays a critical role in determining the superior functions of female bone marrow-derived mesenchymal stem cells in cell therapy against pulmonary arterial hypertension by regulating [Ca(2+)]i signal-associated cellular behaviours.