V3: an enigmatic isoform of the proteoglycan versican.

V3 is an isoform of the extracellular matrix (ECM) proteoglycan (PG) versican generated through alternative splicing of the versican gene such that the two major exons coding for sequences in the protein core that support chondroitin sulfate (CS) glycosaminoglycan (GAG) chain attachment are excluded. Thus, versican V3 isoform carries no GAGs. A survey of PubMed reveals only 50 publications specifically on V3 versican, so it is a very understudied member of the versican family, partly because to date there are no antibodies that can distinguish V3 from the CS-carrying isoforms of versican, that is, to facilitate functional and mechanistic studies. However, a number of in vitro and in vivo studies have identified the expression of the V3 transcript during different phases of development and in disease, and selective overexpression of V3 has shown dramatic phenotypic effects in "gain and loss of function" studies in experimental models. Thus, we thought it would be useful and instructive to discuss the discovery, characterization, and the putative biological importance of the enigmatic V3 isoform of versican.

N-acetylneuraminate pyruvate lyase controls sialylation of muscle glycoproteins essential for muscle regeneration and function.

Deleterious variants in N-acetylneuraminate pyruvate lyase (NPL) cause skeletal myopathy and cardiac edema in humans and zebrafish, but its physiological role remains unknown. We report generation of mouse models of the disease: NplR63C, carrying the human p.Arg63Cys variant, and Npldel116 with a 116-bp exonic deletion. In both strains, NPL deficiency causes drastic increase in free sialic acid levels, reduction of skeletal muscle force and endurance, slower healing and smaller size of newly formed myofibers after cardiotoxin-induced muscle injury, increased glycolysis, partially impaired mitochondrial function, and aberrant sialylation of dystroglycan and mitochondrial LRP130 protein. NPL-catalyzed degradation of sialic acid in the muscle increases after fasting and injury and in human patient and mouse models with genetic muscle dystrophy, demonstrating that NPL is essential for muscle function and regeneration and serves as a general marker of muscle damage. Oral administration of N-acetylmannosamine rescues skeletal myopathy, as well as mitochondrial and structural abnormalities in NplR63C mice, suggesting a potential treatment for human patients.

Extracellular vesicle-derived circCEBPZOS attenuates postmyocardial infarction remodeling by promoting angiogenesis via the miR-1178-3p/PDPK1 axis.

Emerging studies indicate that extracellular vesicles (EVs) and their inner circular RNAs (circRNAs), play key roles in the gene regulatory network and cardiovascular repair. However, our understanding of EV-derived circRNAs in cardiac remodeling after myocardial infarction (MI) remains limited. Here we show that the level of circCEBPZOS is downregulated in serum EVs of patients with the adverse cardiac remodeling compared with those without post-MI remodeling or normal subjects. Loss-of-function approaches in vitro establish that circCEBPZOS robustly promote angiogenesis. Overexpression of circCEBPZOS in mice attenuates MI-induced left ventricular dysfunction, accompanied by a larger functional capillary network at the border zone. Further exploration of the downstream target gene indicates that circCEBPZOS acts as a competing endogenous RNA by directly binding to miR-1178-3p and thereby inducing transcription of its target gene phosphoinositide-dependent kinase-1 (PDPK1). Together, our results reveal that circCEBPZOS attenuates detrimental post-MI remodeling via the miR-1178-3p/PDPK1 axis, which facilitates revascularization, ultimately improving the cardiac function.

Fat-1 transgenic mice rich in endogenous omega-3 fatty acids are protected from lipopolysaccharide-induced cardiac dysfunction.

AIMS: Cardiac malfunctions developing in result of sepsis are hard to treat so they eventually contribute to the increased mortality. Previous reports indicated for therapeutic potential of exogenous ω-3 polyunsaturated fatty acids (PUFA) in sepsis, but potential benefits of this compound on the malfunctional heart have not been explored yet. In the present study, we investigated whether the constantly elevated levels of endogenous ω-3 PUFA in transgenic fat-1 mice would alleviate the lipopolysaccharide (LPS)-induced cardiac failure and death. METHODS AND RESULTS: After both wild type (WT) and transgenic fat-1 mice were challenged with LPS, a Kaplan-Meier curve and echocardiography were performed to evaluate the survival rates and cardiac function. Proteomics analysis, RT-PCR, western blotting, immune-histochemistry, and transmission electron microscopy were further performed to investigate the underlying mechanisms. Results showed that transgenic fat-1 mice exhibited the significantly lower mortality after LPS challenge as compared with their WT counterparts (30% vs. 42.5%, P < 0.05). LPS injection consistently impaired the left ventricular contractile function and caused the cardiac injury in the wild type mice, but not significantly affected the fat-1 mice (P < 0.05). Proteomic analyses, ELISA, and immunohistochemistry further revealed that myocardium of the LPS-challenged fat-1 mice demonstrated the significantly lower levels of pro-inflammatory markers and ROS than WT mice. Meaningfully, the LPS-treated fat-1 mice also demonstrated a significantly higher levels of LC3 II/I and Atg7 expressions than the LPS-treated WT mice (P < 0.05), as well as displayed a selectively increased levels of peroxisome proliferator-activated receptor (PPAR) γ and sirtuin (Sirt)-1 expression, associated with a parallel decrease in NFκB activation. CONCLUSIONS: The fat-1 mice were protected from the detrimental LPS-induced inflammation and oxidative stress, and exhibited enhancement of the autophagic flux activities, associating with the increased Sirt-1 and PPARγ signals.

Efficacy of Sodium Tanshinone IIA Sulfonate in Patients with Non-ST Elevation Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention: Results from a Multicentre, Controlled, Randomized Trial.

BACKGROUND: Sodium tanshinone IIA sulfonate (STS) has been widely used by Chinese medicine practitioners for chronic cardiovascular diseases. However, its direct clinical efficacy in patients with acute coronary syndrome following percutaneous coronary intervention (PCI) has not been reported yet. The present trial aimed to investigate potential cardioprotection of STS in patients undergoing PCI for non-ST elevation acute coronary syndrome (NSTE-ACS). METHODS: In a randomized, double-blind, placebo-controlled trial, 372 patients with NSTE-ACS were randomly assigned to receive STS (n = 192) or saline (n = 180) for 2 days before and 3 days after PCI along with standard therapy. The primary endpoint was the composite incidence of major adverse cardiac events (MACEs), including death, non-fatal myocardial infarction, repeated revascularization of the target vessel, and stent thrombosis, within 30 days after PCI. RESULTS: The 30-day MACEs occurred in 18.8% of the patients in the STS group and in 27.2% of the patients in the control group (P = 0.038); this difference was mostly driven by reduction of myocardial infarction incidence (17.2% vs. 26.7%, P = 0.027). Post-procedural elevation of troponin-I was also significantly lower in the STS group (26.56% vs. 47.78%, P < 0.001). Multivariable analysis identified STS as a predictor of decreased risk of MACE occurrence (odds ratio: 0.60, 95% confidence interval: 0.36 to 0.99; P = 0.045). CONCLUSION: Addition of STS to the standard treatments recommended by the current practice guidelines in patients with NSTE-ACS undergoing PCI could reduce myocardial injury and the occurrence of short-term cardiovascular events, primarily driven by non-fatal myocardial infarction. TRIAL REGISTRATION: ChiCTR-TRC-14005182.

Beneficial Effects of Baduanjin Exercise on Left Ventricular Remodelling in Patients after Acute Myocardial Infarction: an Exploratory Clinical Trial and Proteomic Analysis.

BACKGROUND: The beneficial effects of physical exercise on cardiac remodelling improvement after myocardial infarction have already been suggested. However, the results of previous clinical trials have not been consistent. Moreover, the putative molecular mechanisms leading to the clinically observed effects of physical exercise still remain elusive. AIM: We aimed to evaluate whether the well-defined and strictly controlled traditional Chinese Qigong Baduanjin exercise (BE) would attenuate the adverse left ventricular (LV) remodelling in patients with ST-elevation myocardial infarction (STEMI). METHODS: A total of 110 clinically stable STEMI patients, following successful revascularization of their infarcted coronary arteries, were randomized and enrolled in two groups: 56 were subjected to a 12-week BE-based cardiac rehabilitation programme (BE group), and the remaining 54 were exposed to the usual physical exercise (control group) for the same time period. The primary outcome was the change from baseline to 6 months in the echocardiographic LV end-diastolic volume index (ΔLVEDVi). Proteomic analysis was also performed to uncover associated mechanisms. RESULTS: Compared with the control group, the BE group showed significantly lower ΔLVEDVi (-5.1 ± 1.1 vs. 0.3 ± 1.2 mL/m2, P < 0.01). Proteomic analysis revealed BE-induced variations in the expression of 80 proteins linked to regulation the of metabolic process, immune process, and extracellular matrix reorganization. Furthermore, correlation analyses between the validated serum proteomes and primary endpoint demonstrated a positive association between ΔLVEDVi and MMP-9 expression, but a negative correlation between ΔLVEDVi and CXCL1 expression. CONCLUSION: This is the first study indicating that BE in STEMI patients can alleviate adverse LV remodelling associated with beneficial energy metabolism adaptation, inflammation curbing, and extracellular matrix organization adjustment.

Potential Mechanism of Dermal Wound Treatment With Preparations From the Skin Gel of Arabian Gulf Catfish: A Unique Furan Fatty Acid (F6) and Cholesta-3,5-Diene (S5) Recruit Neutrophils and Fibroblasts to Promote Wound Healing.

Preparations from Arabian Gulf catfish (Arius bilineatus, Val) epidermal gel secretion (PCEGS) effectively heal chronic wounds in diabetic patients. However, specific lipid components of PCEGS that are responsible for various aspects of wound healing are unknown. Here, we report for the first time that, i) a unique preparation containing only proteins and lipids (Fraction B, FB), derived from the PCEGS accelerated the healing of experimental dermal wounds in female rats (transdermal punch biopsy) in vivo. Histological analyses showed that topical treatment of these wounds with FB promoted the migration of fibroblasts, facilitated the production of extracellular matrix (collagen, fibronectin), induced capillary formation and recruitment of immune cells, and accelerated overall wound healing by day 4 (tested at 1, 2, 3, 4, and 10 days; n=15 for vehicle; n=15 for FB treatment), ii) the lipids responsible for different stages of wound healing were separated into a protein-free bioactive lipid fraction, Ft, which contained a few common long-chain fatty acids, a unique furan fatty acid (F6) and a cholesterol metabolite, cholesta-3,5-diene (S5). Ft (the partially purified lipid fraction of PCEGS), and F6 and S5 present in Ft, proved to be bioactive for wound healing in human dermal fibroblasts. Ft increased the production and extracellular deposition of collagen and fibronectin, ex vivo, iii) Ft and its subcomponents, pure F6 and S5, also promoted human dermal fibroblast migration into the scratch wound gaps, ex vivo, iv) Ft, F6, and S5 promoted the recruitment of neutrophils (Green fluorescence protein labeled) to the site of injury in the transected tailfins of transgenic zebrafish, in vivo, v) Ft, but not F6 or S5, promoted the regeneration of tissues at the wound site in the transgenic zebrafish tailfin, in vivo. Therefore, we conclude that lipid fraction Ft from PCEGS contains the components necessary to promote complete wound healing, and F6 and S5 are responsible for promoting fibroblast and neutrophil recruitment to the site of wounds.

Addition of Chinese herbal remedy, Tongguan Capsules, to the standard treatment in patients with myocardial infarction improve the ventricular reperfusion and remodeling: Proteomic analysis of possible signaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Tongguan Capsules (TGC), a patented Chinese herbal remedy containing Salvia miltiorrhiza, Astragalus membranaceus, Borneolum syntheticum and Grasshopper, has been previously tested in the experimental model of animal hearts subjected to ischemia/reperfusion injury and its cardioprotective effect has been described. AIM OF THE STUDY: This clinical trial was aimed at investigation whether the administration of TGC to patients suffered myocardial infarction (MI), would diminish dilation of the left ventricular (LV) and reduce development of the adverse clinical consequences. METHODS: Eligible patients were enrolled and randomized 1:1 to TGC (4.5 g/d for 6 months) superimposed on standard treatment for MI, or the control group receiving the standard protocol alone. The outcomes of this trial were valued after 6 months and reported as a mean change from the baseline in LV end-systolic volume index (LVESVI) and as a frequency of MI recurrence, target-vessel revascularization, severity of heart failure or significant arrhythmia that required the additional therapy within 6 months. In addition, arrays with a panel of specific antibodies were used to assess levels of major cytokines and other pathophysiologic markers, that prompted conclusions about the mechanisms of the ultimate clinical outcomes in both patient's subgroups. RESULTS: Meaningfully, obtained results indicated that MI patients randomly assigned to the TGC treatment, demonstrated a significant reduction of LVESVI (-4.03 ± 0.73 vs. 1.59 ± 0.43 mL/m2, P < 0.001) and a lower incidence of the major adverse cardiovascular events (5.45% vs. 11.44%, P = 0.033). Meaningfully, those patients consistently demonstrated lower serum levels of major inflammatory cytokines, as well as reduced levels of markers of myocardial apoptosis and fibrosis. CONCLUSION: Addition of TGC to the current conventional treatment of MI patients, significantly reduced their adverse LV remodeling and contributed to the more positive clinical outcome. TRIAL REGISTRATION: ChiCTR-IPR-17011618.

Exploration of Multiple Signaling Pathways Through Which Sodium Tanshinone IIA Sulfonate Attenuates Pathologic Remodeling Experimental Infarction.

The level of maladaptive myocardial remodeling consistently contributes to the poor prognosis of patients following a myocardial infarction (MI). In this study, we investigated whether and how sodium tanshinone IIA sulfonate (STS) would attenuate the post-infarct cardiac remodeling in mice model of MI developing after surgical ligation of the left coronary artery. All mice subjected to experimental MI or to the sham procedure were then treated for the following 4 weeks, either with STS or with a vehicle alone. Results of our studies indicated that STS treatment of MI mice prevented the left ventricular dilatation and improved their cardiac function. Results of further tests, aimed at mechanistic explanation of the beneficial effects of STS, indicated that treatment with this compound enhanced the autophagy and, at the same time, inhibited apoptosis of the cardiomyocytes. Meaningfully, we have also established that myocardium of STS-treated mice displayed significantly higher levels of adenosine monophosphate kinase than their untreated counterparts and that this effect additionally associated with the significantly diminished activities of apoptotic promoters: mammalian target of rapamycin and P70S6 kinase. Moreover, we also found that additional administration of the adenosine monophosphate kinase inhibitor (compound C) or autophagy inhibitor (chloroquine) practically eliminated the observed beneficial effects of STS. In conclusion, we suggest that the described multistage mechanism triggered by STS treatment enhanced autophagy, thereby attenuating pathologic remodeling of the post-infarct hearts.

Sodium tanshinone IIA sulfonate prevents the adverse left ventricular remodelling: Focus on polymorphonuclear neutrophil-derived granule components.

AIMS: The aims of this study were to evaluate the effects of sodium tanshinone IIA sulfonate (STS) on left ventricular (LV) remodelling after for ST-elevated myocardial infarction (STEMI). METHODS AND RESULTS: In this prospective, randomized clinical trial, 101 patients with the ST-elevated MI (STEMI) and a successful reperfusion were immediately randomized to receive STS (80 mg qd for 7 days) or saline control, along with standard therapy. The primary effectiveness endpoint is the % change in LV end diastolic volumes index (%∆ LVEDVi) as measured by echocardiography from baseline to 6 months. Secondary effectiveness endpoints include 6-month period for major adverse cardiac events (MACE), including the occurrence of recurrent myocardial infarction, death, hospitalization for heart failure and malignant arrhythmia. The 6-month changes in %∆ LVEDVi were significantly smaller in the STS group than in the control group [-5.05% vs 3.32%; P < 0.001]. With respect to MACE, there was a significant difference between those who received STS (8.16%) and those patients on control (26.00%) (P = 0.019). Meaningfully, results of parallel tests aimed at mechanistic explanation of the reported clinical effects, revealed a significantly reduced levels of neutrophils-derived granule components in the blood of STS treated patients. CONCLUSION: We found that short-term treatment with STS reduced progressive left ventricular remodelling and subsequent better clinical outcome that could be mechanistically linked to the inhibition of the ultimate damage of infarcted myocardium by infiltrating neutrophils.

Tumour cell blebbing and extracellular vesicle shedding: key role of matrikines and ribosomal protein SA.

BACKGROUND: Carcinogenesis occurs in elastin-rich tissues and leads to local inflammation and elastolytic proteinase release. This contributes to bioactive matrix fragment (Matrikine) accumulation like elastin degradation products (EDP) stimulating tumour cell invasive and metastatic properties. We previously demonstrate that EDPs exert protumoural activities through Hsp90 secretion to stabilised extracellular proteinases. METHODS: EDP influence on cancer cell blebbing and extracellular vesicle shedding were examined with a videomicroscope coupled with confocal Yokogawa spinning disk, by transmission electron microscopy, scanning electron microscopy and confocal microscopy. The ribosomal protein SA (RPSA) elastin receptor was identified after affinity chromatography by western blotting and cell immunolocalisation. mRNA expression was studied using real-time PCR. SiRNA were used to confirm the essential role of RPSA. RESULTS: We demonstrate that extracellular matrix degradation products like EDPs induce tumour amoeboid phenotype with cell membrane blebbing and shedding of extracellular vesicle containing Hsp90 and proteinases in the extracellular space. EDPs influence intracellular calcium influx and cytoskeleton reorganisation. Among matrikines, VGVAPG and AGVPGLGVG peptides reproduced EDP effects through RPSA binding. CONCLUSIONS: Our data suggests that matrikines induce cancer cell blebbing and extracellular vesicle release through RPSA binding, favouring dissemination, cell-to-cell communication and growth of cancer cells in metastatic sites.

Isolation and characterization of patient-derived CNS metastasis-associated stromal cell lines.

The functional role of human derived stromal cells in the tumor microenviornment of CNS metastases (CM) remain understudied. The purpose of the current study was to isolate and characterize stromal cells of the tumor microenvironment in CM. Four different patient-derived cell lines (PDCs) of stromal and one PDC of tumorigenic origin were generated from breast or lung CM. PDCs were analyzed by DNA/RNA sequencing, DNA methylation profiling, and immunophenotypic assays. The stromal derived PDCs were termed CNS metastasis-associated stromal cells (cMASCs). Functional analysis of cMASCs was tested by co-implanting them with tumorigenic cells in mice. cMASCs displayed normal genotypes compared with tumorigenic cell lines. RNA-seq and DNA methylation analyses demonstrated that cMASCs highly resembled each other, suggesting a common cell of origin. Additionally, cMASCs revealed gene expression signatures associated with cancer associated fibroblasts (CAFs), epithelial to mesenchymal transition, mesenchymal stem cells and expressed high levels of collagen. Functionally, cMASCs restricted tumor growth, and induced desmoplasia in vivo, suggesting that cMASCs may promote a protective host response to impede tumor growth. In summary, we demonstrated the isolation, molecular characterization and functional role of human derived cMASCs, a subpopulation of cells in the microenvironment of CM that have tumor inhibitory functions.

Experimental Right Ventricular Hypertension Induces Regional ß1-Integrin-Mediated Transduction of Hypertrophic and Profibrotic Right and Left Ventricular Signaling.

BACKGROUND: Development of right ventricular (RV) hypertension eventually contributes to RV and left ventricular (LV) myocardial fibrosis and dysfunction. The molecular mechanisms are not fully elucidated. METHODS AND RESULTS: Pulmonary artery banding was used to induce RV hypertension in rats in vivo. Then, we evaluated cardiac function and regional remodeling 6 weeks after pulmonary artery banding. To further elucidate mechanisms responsible for regional cardiac remodeling, we also mimicked RV hypertensive stress by cyclic mechanical stretching applied to confluent cultures of cardiac fibroblasts, isolated from the RV free wall, septal hinge points, and LV free wall. Echocardiography and catheter evaluation demonstrated that rats in the pulmonary artery banding group developed RV hypertension with leftward septal displacement, LV compression, and increased LV end-diastolic pressures. Picrosirius red staining indicated that pulmonary artery banding induced marked RV fibrosis and dysfunction, with prominent fibrosis and elastin deposition at the septal hinge points but less LV fibrosis. These changes were associated with proportionally increased expressions of integrin-ß1 and profibrotic signaling proteins, including phosphorylated Smad2/3 and transforming growth factor-ß1. Moreover, mechanically stretched fibroblasts also expressed significantly increased levels of α-smooth muscle actin, integrin-ß1, transforming growth factor-ß1, collagen I deposition, and wrinkle formation on gel assays, consistent with myofibroblast transformation. These changes were not observed in parallel cultures of mechanically stretched fibroblasts, preincubated with the integrin inhibitor (BTT-3033). CONCLUSIONS: Experimentally induced RV hypertension triggers regional RV, hinge-point, and LV integrin ß1-dependent mechanotransduction signaling pathways that eventually trigger myocardial fibrosis via transforming growth factor-ß1 signaling. Reduced LV fibrosis and preserved global function, despite geometrical and pressure aberrations, suggest a possible elastin-mediated protective mechanism at the septal hinge points.

Mice, double deficient in lysosomal serine carboxypeptidases Scpep1 and Cathepsin A develop the hyperproliferative vesicular corneal dystrophy and hypertrophic skin thickenings.

Vasoactive and mitogenic peptide, endothelin-1 (ET-1) plays an important role in physiology of the ocular tissues by regulating the growth of corneal epithelial cells and maintaining the hemodynamics of intraocular fluids. We have previously established that ET-1 can be degraded in vivo by two lysosomal/secreted serine carboxypeptidases, Cathepsin A (CathA) and Serine Carboxypeptidase 1 (Scpep1) and that gene-targeted CathAS190A /Scpep1-/- mice, deficient in CathA and Scpep1 have a prolonged half-life of circulating ET-1 associated with systemic hypertension. In the current work we report that starting from 6 months of age, ~43% of CathAS190A /Scpep1-/- mice developed corneal clouding that eventually caused vision impairment. Histological evaluation of these mice demonstrated a selective fibrotic thickening and vacuolization of the corneas, resembling human hyperproliferative vesicular corneal stromal dystrophy and coexisting with a peculiar thickening of the skin epidermis. Moreover, we found that cultured corneal epithelial cells, skin fibroblasts and vascular smooth muscle cells derived from CathA/Scpep1-deficient mice, demonstrated a significantly higher proliferative response to treatment with exogenous ET-1, as compared with cells from wild type mice. We also detected increased activation level of ERK1/2 and AKT kinases involved in cell proliferation in the ET-1-treated cultured cells from CathA/Scpep1 deficient mice. Together, results from our experimental model suggest that; in normal tissues the tandem of serine carboxypeptidases, Scpep1 and CathA likely constitutes an important part of the physiological mechanism responsible for the balanced elimination of heightened levels of ET-1 that otherwise would accumulate in tissues and consequently contribute to development of the hyper-proliferative corneal dystrophy and abnormal skin thickening.

Traditional Chinese medicine, Danlou tablets alleviate adverse left ventricular remodeling after myocardial infarction: results of a double-blind, randomized, placebo-controlled, pilot study.

BACKGROUND: Danlou tablets, a patented Chinese Medicine, have been long approved for the treatment of ischemic heart disease in China. While numerous empirical observations suggested Danlou tablets could decrease frequency and duration of angina pectoris attacks, evidence supporting its efficacy on cardiac remodeling remains inadequate. Therefore, this pilot trial was designed to determine whether Danlou tablets would reduce adverse left ventricular (LV) remodeling in patients with myocardial infarction (MI). METHODS AND RESULTS: Eligible patients with acute MI were enrolled and randomly assigned to Danlou tablets or placebo groups, superimposed on standard treatment for MI. Then, in addition to assessment of the clinical outcome, the changes in LV volumes were evaluated by a serial echocardiography. In total, 83 patients (Danlou tablets 42 and placebo 41) completed 90 days of treatment and had complete baseline and outcome data. Standard echocardiographic evaluations revealed significant differences in the change of LV end-diastolic volume index (LVEDVi) between group of patients treated with Danlou tablets and the placebo group (-4.49 ± 7.29 vs. -0.34 ± 9.01 mL/m2, P < 0.001). The reduction in LVEDVi was independent of beta-blocker, ACE inhibitors/ARBs use. Furthermore, treatment with Danlou tablets significantly reduced LV end-systolic volume index (-4.09 ± 5.85 vs. -0.54 ± 5.72 mL/m2, P < 0.001) and improved the LV ejection fraction (4.83 ± 9.23 vs. 0.23 ± 8.15 %, P < 0.001), as compared to placebo. Meaningfully, the incidence of the major adverse cardiovascular events was also lower in patients receiving Danlou tablets (P < 0.05). CONCLUSION: Superimposed on the standard pharmacologic treatment, Danlou tablets significantly reversed post-MI adverse LV remodeling, thereby contributed to the overall positive clinical outcome. TRIAL REGISTRATION: clinicaltrials.gov identifier NCT02675322 (February 1, 2016).

Synthetic ligands of the elastin receptor induce elastogenesis in human dermal fibroblasts via activation of their IGF-1 receptors.

BACKGROUND: We have previously reported that a mixture of peptides obtained after chemical or enzymatic degradation of bovine elastin, induced new elastogenesis in human skin. OBJECTIVE: Now, we investigated the elastogenic potential of synthetic peptides mimicking the elastin-derived, VGVAPG sequence, IGVAPG sequence that we found in the rice bran, and a similar peptide, VGVTAG that we identified in the IGF-1-binding protein-1 (IGFBP-1). RESULTS: We now demonstrate that treatment with each of these xGVxxG peptides (recognizable by the anti-elastin antibody), up-regulated the levels of elastin-encoding mRNA, tropoelastin protein, and the deposition of new elastic fibers in cultures of human dermal fibroblasts and in cultured explants of human skin. Importantly, we found that such induction of new elastogenesis may involve two parallel signaling pathways triggered after activation of IGF-1 receptor. In the first one, the xGVxxG peptides interact with the cell surface elastin receptor, thereby causing the downstream activation of the c-Src kinase and a consequent cross-activation of the adjacent IGF-1R, even in the absence of its principal ligand. In the second pathway their hydrophobic association with the N-terminal domain (VGVTAG) of the serum-derived IGFBP-1 induces conformational changes of this IGF-1 chaperone allowing for the release of its cargo and a consequent ligand-specific phosphorylation of IGF-1R. CONCLUSION: We present a novel, clinically relevant mechanism in which products of partial degradation of dermal elastin may stimulate production of new elastic fibers by dermal fibroblasts. Our findings particularly encourage the use of biologically safe synthetic xGVxxG peptides for regeneration of the injured or aged human skin.

The antidiabetic hormone glucagon-like peptide-1 induces formation of new elastic fibers in human cardiac fibroblasts after cross-activation of IGF-IR.

Glucagon-like peptide 1 (GLP-1) is a metabolic hormone involved in the stimulation of insulin biosynthesis and secretion. It has been recently reported that GLP-1 also exerts cardioprotective effects and facilitates functional recovery after myocardial infarction through GLP-1 receptor-mediated signaling in cardiomyocytes. GLP-1 treatment has been also demonstrated to produce sustained improvement in cardiac function in long-term studies, suggesting the involvement of mechanisms beyond the acute metabolic and cytoprotective effects. For example, the possible interaction of GLP-1 with the cardiac fibroblasts, which are responsible for the postinfarct remodeling and extracellular matrix production, has not been previously explored. Here, we report that cultures of human cardiac fibroblasts treated with GLP-1 peptides display a selective up-regulation in elastin gene expression and a consequent increase in elastic fibers production, in the absence of the classic GLP-1 receptor. Importantly, we provide experimental evidence that this GLP-1-induced elastogenesis is triggered through the cross-activation of the IGF-I receptor. Because GLP-1 does not stimulate deposition of collagen I, nor promote the proliferation or apoptosis of cultured cardiac fibroblasts, we speculate that its elastogenic effect may also contribute to the beneficial remodeling of the human heart after myocardial infarction.

Type V OI primary osteoblasts display increased mineralization despite decreased COL1A1 expression.

CONTEXT: Patients with type V osteogenesis imperfecta (OI) are heterozygous for a dominant IFITM5 c.-14C>T mutation, which adds five residues to the N terminus of bone-restricted interferon-induced transmembrane-like protein (BRIL), a transmembrane protein expressed in osteoblasts. Type V OI skeletal findings include hyperplastic callus formation, ossification of the forearm interosseous membrane, and dense metaphyseal bands. OBJECTIVE: The objective of this study was to examine the role of osteoblasts in the active mineralization traits of type V OI and the effect of the IFITM5 mutation on type I collagen. METHODS: We identified eight patients with the IFITM5 c.-14C>T mutation. Cultured osteoblasts from type V OI patients were used to study osteoblast differentiation and mineralization. RESULTS: We verified the expression and stability of mutant IFITM5 transcripts. In differentiated type V OI primary osteoblasts in culture, the IFITM5 expression and BRIL level is comparable with control. Both early and late markers of osteoblast differentiation are increased in type V OI osteoblasts. Mineralization, assayed by alizarin red staining, was increased in type V OI osteoblasts compared with control. However, type V OI osteoblasts have significantly decreased COL1A1 transcripts in mid- to late differentiation. Type I collagen protein is concomitantly decreased, with decreased cross-linked collagen in matrix and altered appearance of fibrils deposited in culture. CONCLUSIONS: This study demonstrates that type V OI mineralization has a gain-of-function mechanism at the osteoblast level, which likely underlies the overactive tissue mineralization seen in patients. Decreased type I collagen expression, secretion, and matrix incorporation establish type V OI as a collagen-related defect.