Hepatocyte growth factor protects small airway epithelial cells from apoptosis induced by tumor necrosis factor-alpha or oxidative stress

Hydrogen-induced disruption of the airway mucus barrier enhances nebulized RNA delivery to reverse pulmonary fibrosis

Nebulized RNA therapies are well suited for treating respiratory diseases, in particular pulmonary fibrosis (PF); however, effective delivery remains challenging. In this study, we present a highly efficient aerosol inhalation system that enables high levels of in vivo transfection efficiency in lung macrophages, yielding durable responses against PF. First, we established a nose-only aerosol inhalation device integrated with a hydrogen supplement system. This setup enables the precise administration of lipid nanoparticles (LNPs) at a controlled low dose, while simultaneously delivering the optimal concentration of therapeutic hydrogen gas. We further developed a hybrid lipid NP (HNP) by hybridizing a pH-dependent charge-inverting lipid film with apoptotic T cell membranes to enhance endosomal escape and trigger macrophage production of hepatocyte growth factor for lung repair. We demonstrated that the hydrogen flow-induced shear stresses disrupt the NP-mucus interaction, enhancing the deposition of aerosolized HNPs/TGFβ1 siRNA within fibrotic lung lesions, effectively blocking fibrogenic signaling pathways and offering a clinically viable strategy for combating PF.

Immunofibrotic drivers of impaired lung function in postacute sequelae of SARS-CoV-2 infection

BACKGROUNDIndividuals recovering from COVID-19 frequently experience persistent respiratory ailments, which are key elements of postacute sequelae of SARS-CoV-2 infection (PASC); however, little is known about the underlying biological factors that may direct lung recovery and the extent to which these are affected by COVID-19 severity.METHODSWe performed a prospective cohort study of individuals with persistent symptoms after acute COVID-19, collecting clinical data, pulmonary function tests, and plasma samples used for multiplex profiling of inflammatory, metabolic, angiogenic, and fibrotic factors.RESULTSSixty-one participants were enrolled across 2 academic medical centers at a median of 9 weeks (interquartile range, 6-10 weeks) after COVID-19 illness: n = 13 participants (21%) had mild COVID-19 and were not hospitalized, n = 30 participants (49%) were hospitalized but were considered noncritical, and n = 18 participants (30%) were hospitalized and in the intensive care unit (ICU). Fifty-three participants (85%) had lingering symptoms, most commonly dyspnea (69%) and cough (58%). Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and diffusing capacity for carbon monoxide (DLCO) declined as COVID-19 severity increased (P < 0.05) but these values did not correlate with respiratory symptoms. Partial least-squares discriminant analysis of plasma biomarker profiles clustered participants by past COVID-19 severity. Lipocalin-2 (LCN2), MMP-7, and HGF identified by our analysis were significantly higher in the ICU group (P < 0.05), inversely correlated with FVC and DLCO (P < 0.05), and were confirmed in a separate validation cohort (n = 53).CONCLUSIONSubjective respiratory symptoms are common after acute COVID-19 illness but do not correlate with COVID-19 severity or pulmonary function. Host response profiles reflecting neutrophil activation (LCN2), fibrosis signaling (MMP-7), and alveolar repair (HGF) track with lung impairment and may be novel therapeutic or prognostic targets.FundingNational Heart, Lung, and Blood Institute (K08HL130557 and R01HL142818), American Heart Association (Transformational Project Award), the DeLuca Foundation Award, a donation from Jack Levin to the Benign Hematology Program at Yale University, and Duke University.

Phase I/II Clinical Trial of Autologous Activated Platelet-Rich Plasma (aaPRP) in the Treatment of Severe Coronavirus Disease 2019 (COVID-19) Patients

Background

The outbreak of Coronavirus Disease 2019 (COVID-19) has been increasing rapidly. This disease causes an increase in proinflammatory cytokine production that leads to cytokine storm or cytokine release syndrome (CRS). Autologous activated platelet-rich plasma (aaPRP) contains various types of growth factors and anti-inflammatory cytokines that may have the potential to suppress CRS. This study of phase I/II trial was aimed to evaluate the safety and efficacy of aaPRP to treat severe COVID-19 patients.

Methods

A total of 10 severe COVID-19 patients from Koja Regional Public Hospital (Koja RPH) were admitted to the intensive care unit (ICU). All patients received aaPRP administration three times. Primary outcomes involving the duration of hospitalization, oxygen needs, time of recovery, and mortality were observed. Secondary outcomes involving C-reactive protein (CRP), neutrophil, lymphocyte, and lymphocyte-to-CRP (LCR) and neutrophil-lymphocyte ratio (NLR) were analyzed.

Results

All patients were transferred to the ICU with a median duration of 9 days. All patients received oxygen at enrollment and nine of ten patients recovered from the ICU and transferred to the ward room. There was one patient who passed away in the ICU due to heart failure. The results of secondary outcomes showed that CRP value and lymphocytes counts were significantly decreased while neutrophils, LCR, and NLR were slightly increased after aaPRP administration.

Conclusions

Our results of the phase I/II trial demonstrated that the use of aaPRP in severe COVID-19 patients was safe and not associated with serious adverse events, which showed that aaPRP was a promising adjunctive therapy for severe COVID-19 patients.

Immuno-fibrotic drivers of impaired lung function in post-acute sequelae of SARS-CoV-2 infection (PASC)

Introduction:

Subjects recovering from COVID-19 frequently experience persistent respiratory ailments; however, little is known about the underlying biological factors that may direct lung recovery and the extent to which these are affected by COVID-19 severity.

Methods:

We performed a prospective cohort study of subjects with persistent symptoms after acute COVID-19, collecting clinical data, pulmonary function tests, and plasma samples used for multiplex profiling of inflammatory, metabolic, angiogenic, and fibrotic factors.

Results:

Sixty-one subjects were enrolled across two academic medical centers at a median of 9 weeks (interquartile range 6–10) after COVID-19 illness: n=13 subjects (21%) mild/non-hospitalized, n=30 (49%) hospitalized/non-critical, and n=18 subjects (30%) hospitalized/intensive care (“ICU”). Fifty-three subjects (85%) had lingering symptoms, most commonly dyspnea (69%) and cough (58%). Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and diffusing capacity for carbon monoxide (DLCO) declined as COVID-19 severity increased (P<0.05), but did not correlate with respiratory symptoms. Partial least-squares discriminant analysis of plasma biomarker profiles clustered subjects by past COVID-19 severity. Lipocalin 2 (LCN2), matrix metalloproteinase-7 (MMP-7), and hepatocyte growth factor (HGF) identified by the model were significantly higher in the ICU group (P<0.05) and inversely correlated with FVC and DLCO (P<0.05), and were confirmed in a separate validation cohort (n=53).

Conclusions:

Subjective respiratory symptoms are common after acute COVID-19 illness but do not correlate with COVID-19 severity or pulmonary function. Host response profiles reflecting neutrophil activation (LCN2), fibrosis signaling (MMP-7), and alveolar repair (HGF) track with lung impairment and may be novel therapeutic or prognostic targets.

Funding:

The study was funded in part by the NHLBI (K08HL130557 to BDK and R01HL142818 to HJC), the DeLuca Foundation Award (AP), a donation from Jack Levin to the Benign Hematology Program at Yale, and Divisional/Departmental funds from Duke University.

Antiapoptotic Properties of Mesenchymal Stem Cells in a Mouse Model of Corneal Inflammation

Mesenchymal stem cells (MSCs) represent a population of adult stem cells that have potent immunoregulatory, anti-inflammatory, and antiapoptotic properties. In addition, they have ability to migrate to the site of inflammation or injury, where they contribute to the regeneration and healing process. For these properties, MSCs have been used as therapeutic cells in several models, including treatment of damages or disorders of the ocular surface. If the damage of the ocular surface is extensive and involves a limbal region where limbal stem cell reside, MSC therapy has been proved as the effective treatment approach. Although the anti-inflammatory properties of MSCs have been well characterized, mechanisms of antiapoptotic action of MSCs are not well recognized. Using a chemically damaged cornea in a mouse model, we showed that the injury decreases expression of the gene for antiapoptotic molecule Bcl-2 and increases the expression of proapoptotic genes Bax and p53. These changes were attenuated by local transplantation of MSCs after corneal damage. The antiapoptotic effect of MSCs was tested in an in vitro model of co-cultivation of corneal explants with MSCs. The apoptosis of corneal cells in the explants was induced by proinflammatory cytokines and was significantly inhibited in the presence of MSCs. The antiapoptotic effect of MSCs was mediated by paracrine action, as confirmed by separation of the explants in inserts or by supernatants from MSCs. In addition, MSCs decreased the expression of genes for the molecules associated with endoplasmic reticulum stress Atf4, Bip, and p21, which are associated with apoptosis. The results show that MSCs inhibit the expression of proapoptotic genes and decrease the number of apoptotic cells in the damaged corneas, and this action might be one of the mechanisms of the therapeutic action of MSCs.

Platelet Lysate Nebulization Protocol for the Treatment of COVID-19 and Its Sequels: Proof of Concept and Scientific Rationale

One of the most severe effects of coronavirus disease 2019 (COVID-19) is lung disorders such as acute respiratory distress syndrome. In the absence of effective treatments, it is necessary to search for new therapies and therapeutic targets. Platelets play a fundamental role in respiratory disorders resulting from viral infections, being the first line of defense against viruses and essential in maintaining lung function. The direct application of platelet lysate (PL) obtained from the platelet-rich plasma of healthy donors could help in the improvement of the patient due its anti-inflammatory, immunomodulatory, antifibrotic, and repairing effects. This work evaluates PL nebulization by analyzing its levels of growth factors and its biological activity on lung fibroblast cell cultures, besides describing a scientific basis for its use in this kind of pathology. The data of the work suggest that the molecular levels and biological activity of the PL are maintained after nebulization. Airway administration would allow acting directly on the lung tissue modulating inflammation and stimulating reparative processes on key structures such as the alveolocapillary barrier, improving the disease and sequels. The protocol developed in this work is a first step for the study of nebulized PL both in animal experimentation and in clinical trials.

Airway Remodeling Factors During Early-Life Rhinovirus Infection and the Effect of Premature Birth

Background: Early rhinovirus (RV) infection is a strong risk factor for asthma development. Airway remodeling factors play a key role in the progression of the asthmatic condition. We hypothesized that RV infection in young children elicits the secretion of growth factors implicated in airway remodeling and asthma progression. Methods: We examined the nasal airway production of remodeling factors in children ( ≤ 2 years old) hospitalized due to PCR-confirmed RV infection. Airway remodeling proteins included: MMP-1, MMP-2, MMP-7, MMP-9, MMP-10, TIMP-1, TIMP-2, EGF, Angiopoietin-2, G-CSF, BMP-9, Endoglin, Endothelin-1, Leptin, FGF-1, Follistatin, HGF, HB-EGF, PLGF, VEGF-A, VEGF-C, VEGF-D, FGF-2, TGF-β1, TGF-β2, TGF-β3, PDGF AA, PDGF BB, SPARC, Periostin, OPN, and TGF-α. Results: A total of 43 young children comprising RV cases (n = 26) and uninfected controls (n = 17) were included. Early RV infection was linked to (1) enhanced production of several remodeling factors (e.g., HGF, TGFα), (2) lower MMP-9/TIMP-2 and MMP-2/TIMP-2 ratios, and (3) increased MMP-10/TIMP-1 ratios. We also found that relative to term infants, severely premature children had reduced MMP-9/TIMP-2 ratios at baseline. Conclusion: RV infection in young children elicits the airway secretion of growth factors implicated in angiogenesis, fibrosis, and extracellular matrix deposition. Our results highlight the potential of investigating virus-induced airway remodeling growth factors during early infancy to monitor and potentially prevent chronic progression of respiratory disorders in all ages.

Airway Epithelial Dysfunction in Asthma: Relevant to Epidermal Growth Factor Receptors and Airway Epithelial Cells

Airway epithelium plays an important role as the first barrier from external pathogens, including bacteria, viruses, chemical substances, and allergic components. Airway epithelial cells also have pivotal roles as immunological coordinators of defense mechanisms to transfer signals to immunologic cells to eliminate external pathogens from airways. Impaired airway epithelium allows the pathogens to remain in the airway epithelium, which induces aberrant immunological reactions. Dysregulated functions of asthmatic airway epithelium have been reported in terms of impaired wound repair, fragile tight junctions, and excessive proliferation, leading to airway remodeling, which contributes to aberrant airway responses caused by external pathogens. To maintain airway epithelium integrity, a family of epidermal growth factor receptors (EGFR) have pivotal roles in mechanisms of cell growth, proliferation, and differentiation. There are extensive studies focusing on the relation between EGFR and asthma pathophysiology, which describe airway remodeling, airway hypermucus secretion, as well as immunological responses of airway inflammation. Furthermore, the second EGFR family member, erythroblastosis oncogene B2 (ErbB2), has been recognized to be involved with impaired wound recovery and epithelial differentiation in asthmatic airway epithelium. In this review, the roles of the EGFR family in asthmatic airway epithelium are focused on to elucidate the pathogenesis of airway epithelial dysfunction in asthma.

Evaluation of T cell cytokines and their role in recurrent miscarriage

Recurrent miscarriage (RM) is defined as two or more consecutive pregnancy losses that affect approximately 5% of conceived women worldwide. RM is a multi-factorial reproductive problem and has been associated with parental chromosomal abnormalities, embryonic chromosomal rearrangements, uterine anomalies, autoimmune disorders, endocrine dysfunction, thrombophilia, life style factors, and maternal infections. However, the exact cause is still undecided in remaining 50% of cases. Immunological rejection of the embryo due to exacerbated maternal immune reaction against paternal embryonic antigens has been set forth as one of the significant reason for RM. The accurate means that shield the embryo during normal pregnancy from the attack of maternal immune network and dismissal are inadequately implicit. However, it is suggested that the genetically irreconcilable embryo escapes maternal immune rejection due to communication among many vital cytokines exuded at maternal-embryonic interface both by maternal and embryonic cells. Previous investigations suggested the Th1/Th2 dominance in altered immunity of RM patients, according to which the allogenic embryo flees maternal T cell reaction by inclining the Th0 differentiation toward Th2 pathway resulting into diminished pro-inflammatory Th1 immunity. However, recently pro-inflammatory Th17 cells and immunoregulatory Treg cells have been discovered as essential immune players in RM besides Th1/Th2 components. Cytokines are believed to develop a complicated regulatory network so as to establish a state of homeostasis between the semi-allogenic embryo and the maternal immune system. However, an adverse imbalance among cytokines at maternal-embryonic interface perhaps due to their gene polymorphisms may render immunoregulatory means not enough to re-establish homeostasis and thus may collapse pregnancy.

WKYMVm hexapeptide, a strong formyl peptide receptor 2 agonist, attenuates hyperoxia-induced lung injuries in newborn mice

The hexapeptide WKYMVm, which is a strong formyl peptide receptor (FPR) 2 agonist, exhibits pro-angiogenic, anti-inflammatory and anti-apoptotic properties. However, its therapeutic efficacy in bronchopulmonary dysplasia (BPD) has not been tested to date. Here, we investigated whether WKYMVm attenuates hyperoxia-induced lung inflammation and ensuing injuries by upregulating FPR2. The proliferation and tube formation ability of human umbilical vein endothelial cells (HUVECs), along with the level of extracellular signal regulated kinase (ERK) phosphorylation, were evaluated in vitro. Newborn mice were randomly exposed to 80% oxygen or room air for 14 days starting at birth. WKYMVm (2.5 mg/kg) was intraperitoneally administrated daily from postnatal day (P) 5 to P8. At P14, mice were sacrificed for histopathological and morphometric analyses. Along with upregulation of FPR2 and p-ERK, WKYMVm promoted HUVEC cell proliferation and tube formation in vitro. Additionally, WKYMVm promoted proliferation of human pulmonary microvascular endothelial cells (HULEC-5a) and murine pulmonary endothelial and epithelial cells in vitro. WKYMVm significantly attenuated hyperoxia-induced lung inflammation, as evidenced by increased inflammatory cytokines, neutrophils, and alveolar macrophages, and resultant lung injuries, which included impaired alveolarization and angiogenesis, an increased number of apoptotic cells, and reduced levels of growth factors in vivo, such as vascular endothelial growth factor and hepatocyte growth factor. WKYMVm attenuates hyperoxia-induced lung injuries and lung inflammation by upregulating FPR2 and p-ERK.

Therapeutic Implications of Human Umbilical Cord Mesenchymal Stromal Cells in Attenuating Influenza A(H5N1) Virus-Associated Acute Lung Injury

Background

Highly pathogenic avian influenza viruses can cause severe forms of acute lung injury (ALI) in humans, where pulmonary flooding leads to respiratory failure. The therapeutic benefits of bone marrow mesenchymal stromal cells (MSCs) have been demonstrated in a model of ALI due to influenza A(H5N1) virus. However, clinical translation is impractical and limited by a decline in efficacy as the age of the donor increases. Umbilical cord MSCs (UC-MSCs) are easier to obtain by comparison, and their primitive source may offer more-potent therapeutic effects.

Methods

Here we investigate the therapeutic efficacy of UC-MSCs on the mechanisms of pulmonary edema formation and alveolar fluid clearance and protein permeability of A(H5N1)-infected human alveolar epithelial cells. UC-MSCs were also tested in a mouse model of influenza ALI.

Results

We found that UC-MSCs were effective in restoring impaired alveolar fluid clearance and protein permeability of A(H5N1)-infected human alveolar epithelial cells. UC-MSCs consistently outperformed bone marrow MSCs, partly because of greater growth factor secretion of angiopoietin 1 and hepatocyte growth factor. Conditioned UC-MSC medium and UC-MSC exosomes were also able to recapitulate these effects. However, UC-MSCs only slightly improved survival of A(H5N1)-infected mice.

Conclusions

Our results suggest that UC-MSCs are effective in restoring alveolar fluid clearance and protein permeability in A(H5N1)-associated ALI and confer functional in addition to practical advantages over conventional bone marrow MSCs.

Low concentrations of clarithromycin upregulate cellular antioxidant enzymes and phosphorylation of extracellular signal-regulated kinase in human small airway epithelial cells

BACKGROUND

It is well known that low-dose, long-term macrolide therapy is effective against chronic inflammatory airway diseases. Oxidative stress is considered to be a key pathogenesis factor in those diseases. However, the mechanism of action of low-dose, long-term macrolide therapy remains unclear. We have reported that clarithromycin (CAM), which is a representative macrolide antibiotic, could inhibit hydrogen peroxide (H2O2)-induced reduction of the glutathione (GSH)/glutathione disulfide (GSSG) ratio in human small airway epithelial cells (SAECs), via the maintenance of GSH levels through an effect on γ-glutamylcysteine synthetase (γ-GCS) expression. In this study, we examined the influence of CAM against H2O2-induced activities of cellular antioxidant enzymes and phosphorylated extracellular signal regulatory kinase (p-ERK) using SAECs, the main cells involved in chronic airway inflammatory diseases.

METHODS

SAECs were pretreated with CAM (1, 5, and 10 μM) for 72 h, and subsequently exposed to H2O2 (100 μM) for 0.5-2 h. Levels of GSH and GSSG, and activities of glutathione peroxidase (GPx)-1, glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT), heme oxygenase (HO)-1 and p-ERK were assayed. mRNA expressions of GPx-1 and HO-1 were measured using the real-time reverse transcription polymerase chain reaction (RT-PCR). Tukey's multiple comparison test was used for analysis of statistical significance.

RESULTS

Pretreatment with low-dose (1 and 5 μM) CAM for 72 h inhibited H2O2-induced reductions of GPx-1, GR, SOD, CAT and HO-1 activities, and mRNA expressions of GPx-1 and HO-1, and improved the GSH/GSSG ratio. However, these alterations were not observed after pretreatment with high-dose (10 μM) CAM, which suppressed phosphorylation of cell proliferation-associated ERK to cause a significant (p < 0.01) decrease in cell viability.

CONCLUSIONS

CAM is efficacious against deterioration of cellular antioxidant enzyme activity caused by oxidative stress under low-dose, long-term treatment conditions. On the other hand, pretreatment with high-dose CAM suppressed phosphorylation of cell proliferation-associated ERK and decreased cell viability. The present study may provide additional evidence as to why low-dose, long-term administration of macrolides is effective for treating chronic inflammatory airway diseases.

Cross-talk between human airway epithelial cells and 3T3-J2 feeder cells involves partial activation of human MET by murine HGF

There is considerable interest in the ex vivo propagation of primary human basal epithelial stem/progenitor cells with a view to their use in drug development, toxicity testing and regenerative medicine. These cells can be expanded in co-culture with mitotically inactivated 3T3-J2 murine embryonic feeder cells but, similar to other epithelial cell culture systems employing 3T3-J2 cells, the aspects of cross-talk between 3T3-J2 cells and human airway basal cells that are critical for their expansion remain largely unknown. In this study, we investigated secreted growth factors that are produced by 3T3-J2 cells and act upon primary human airway basal cells. We found robust production of hepatocyte growth factor (HGF) from fibroblast feeder cells following mitotic inactivation. Consistent with the limited cross-species reactivity of murine HGF on the human HGF receptor (MET; HGFR), MET inhibition did not affect proliferative responses in human airway basal cells and HGF could not replace feeder cells in this culture system. However, we found that murine HGF is not completely inactive on human airway epithelial cells or cancer cell lines but stimulates the phosphorylation of GRB2-associated-binding protein 2 (GAB2) and signal transducer and activator of transcription 6 (STAT6). Although HGF induces phosphorylation of STAT6 tyrosine 641 (Y641), there is no subsequent STAT6 nuclear translocation or STAT6-driven transcriptional response. Overall, these findings highlight the relevance of cross-species protein interactions between murine feeder cells and human epithelial cells in 3T3-J2 co-culture and demonstrate that STAT6 phosphorylation occurs in response to MET activation in epithelial cells. However, STAT6 nuclear translocation does not occur in response to HGF, precluding the transcriptional activity of STAT6.

Human amniotic mesenchymal stem cells improve ovarian function in natural aging through secreting hepatocyte growth factor and epidermal growth factor

Background

Although many reports show that various kinds of stem cells have the ability to recover function in premature ovarian aging, few studies have looked at stem cell treatment of natural ovarian aging (NOA). We designed this experimental study to investigate whether human amniotic mesenchymal stem cells (hAMSCs) retain the ability to restore ovarian function, and how hAMSCs work in this process.

Methods

To build the NOA mouse model, the mice were fed for 12–14 months normally with young fertile female mice as the normal control group (3–5 months old). Hematoxylin and eosin staining permitted follicle counting and showed the ovarian tissue structure. An enzyme-linked immunosorbent assay was used to detect the serum levels of the sex hormones estradiol (E2), anti-mullerian hormone (AMH), and follicle-stimulating hormone (FSH). The proliferation rate and marker expression level of human ovarian granule cells (hGCs) (ki67, AMH, FSH receptor, FOXL2, and CYP19A1) were measured by flow cytometry (FACS). Cytokines (growth factors) were measured by a protein antibody array methodology. After hepatocyte growth factor (HGF) and epidermal growth factor (EGF) were co-cultured with hGCs, proliferation (ki67) and apoptosis (Annexin V) levels were analyzed by FACS. After HGF and EGF were injected into the ovaries of natural aging mice, the total follicle numbers and hormone levels were tested.

Results

After the hAMSCs were transplanted into the NOA mouse model, the hAMSCs exerted a therapeutic activity on mouse ovarian function by improving the follicle numbers over four stages. In addition, our results showed that hAMSCs significantly promoted the proliferation rate and marker expression level of ovarian granular cells that were from NOA patients. Meanwhile, we found that the secretion level of EGF and HGF from hAMSCs was higher than other growth factors. A growth factor combination (HGF with EGF) improved the proliferation rate and inhibited the apoptosis rate more powerfully after a co-culture with hGCs, and total follicle numbers and hormone levels were elevated to a normal level after the growth factor combination was injected into the ovaries of the NOA mouse model.

Conclusions

These findings provide insight into the notion that hAMSCs play an integral role in resistance to NOA. Furthermore, our present study demonstrates that a growth factor combination derived from hAMSCs plays a central role in inhibiting ovarian aging. Therefore, we suggest that hAMSCs improve ovarian function in natural aging by secreting HGF and EGF.

Electronic supplementary material

The online version of this article (10.1186/s13287-018-0781-9) contains supplementary material, which is available to authorized users.

Effects of low molecular weight heparin on the polarization and cytokine profile of macrophages and T helper cells in vitro

Low molecular weight heparin (LMWH) is widely used in recurrent miscarriage treatment. The anti-coagulant effects are established, while immunological effects are not fully known. Our aim was to assess LMWH effects on activation and polarization of central regulatory immune cells from healthy women, and on placenta tissues from women undergoing elective abortions. Isolated blood monocytes and T helper (Th) cells under different activation and polarizing conditions were cultured with or without LMWH. Flow cytometry showed that LMWH exposure induced increased expression of HLA-DR and CD206 in macrophages. This phenotype was associated with increased secretion of Th17-associated CCL20, and decreased secretion of CCL2 (M2-associated) and CCL22 (Th2), as measured by multiplex bead array. In accordance, LMWH exposure to Th cells reduced the proportion of CD25highFoxp3+ regulatory T-cells, intensified IFN-γ secretion and showed a tendency to increase the lymphoblast proportions. Collectively, a mainly pro-inflammatory effect was noted on two essential tolerance-promoting cells. Although the biological significancies of these in vitro findings are uncertain and need to be confirmed in vivo, they suggest the possibility that immunological effects of LMWH may be beneficial mainly at an earlier gestational age to provide an appropriate implantation process in women with recurrent miscarriage.

The effect of clinically relevant doses of immunosuppressive drugs on human mesenchymal stem cells

Immunosuppressive drugs are used to suppress graft rejection after transplantation and for the treatment of various diseases. The main limitations of their use in clinical settings are severe side effects, therefore alternative approaches are desirable. In this respect, mesenchymal stem cells (MSCs) possess a regenerative and immunomodulatory capacity that has generated considerable interest for their use in cell-based therapy. Currently, MSCs are tested in many clinical trials, including the treatment of diseases which require simultaneous immunosuppressive treatment. Since the molecular targets of immunosuppressive drugs are also present in MSCs, we investigated whether immunosuppressive drugs interact with the activity of MSCs. Human MSCs isolated from the bone marrow (BM) or adipose tissue (AT) were cultured in the presence of clinical doses of five widely used immunosuppressive drugs (cyclosporine A, mycophenolate mofetil, rapamycin, prednisone and dexamethasone), and the influence of these drugs on several factors related to the immunosuppressive properties of MSCs, including the expression of immunomodulatory enzymes, various growth factors, cytokines, chemokines, adhesion molecules and proapoptotic ligands, was assessed. Glucocorticoids, especially dexamethasone, showed the most prominent effects on both types of MSCs and suppressed the expression of the majority of the factors that were tested. A significant increase of hepatocyte growth factor production in AT-MSCs and of indoleamine 2,3-dioxygenase expression in both types of MSCs were the only exceptions. In conclusion, clinically relevant doses of inhibitors of calcineurin, mTOR and IMPDH and glucocorticoids interfere with MSC functions, but do not restrain their immunosuppressive properties. These findings should be taken into account before preparing immunosuppressive strategies combining the use of immunosuppressive drugs and MSCs.

OLR1 and Loxin Expression in PBMCs of Women with a History of Unexplained Recurrent Miscarriage: A Pilot Study

AIMS

The aim of this study was to evaluate the expression of OLR1 and its alternative splicing isoform Loxin in unexplained recurrent miscarriage (uRM).

METHODS

Sixty-three women of reproductive age were recruited and were divided into four groups: 18 pregnant and 23 non-pregnant women with uRM, and 12 pregnant and 10 non-pregnant women with physiological pregnancies. Complementary DNA derived from peripheral blood mononuclear cells (PBMCs) was analyzed by quantitative real-time PCR to evaluate the expression of OLR1 and Loxin. Oxidized low-density lipoproteins (ox-LDLs) were assayed from serum by a commercially available kit.

RESULTS

Pregnant uRM women presented with a higher, though not significant, OLR1/Loxin ratio and a higher ox-LDLs serum level (p ≤ 0.05) compared with pregnant control women. OLR1 and Loxin levels were significantly decreased in non-pregnant uRM women compared with the control (OLR1: 0.00018 vs. 0.00043, p ≤ 0.005; Loxin: 0.00018 vs. 0.00060, p ≤ 0.005, respectively). Loxin expression decreased by about two-thirds (p ≤ 0.005) in pregnant women compared with non-pregnant control women. A higher expression of OLR1 in pregnant women compared with non-pregnant women with uRM (p ≤ 0.05) was observed, but no variation in Loxin expression was observed.

CONCLUSIONS

The results of this study show an association of peripheral OLR1 and Loxin expression levels in uRM women, and they suggest the possible existence of an uncontrolled oxidative stress in these women in the first trimester of pregnancy.

Is Serum Angiotensin-Converting Enzyme Level Useful For Determining Necroinflammatory Activity In Chronic Hepatitis B Infection?

AIM

The purpose of this study was to investigate the relationship between the findings from liver biopsy and the serum angiotensin-converting enzyme (ACE) level to determine whether ACE might serve as a potential noninvasive sign of necroinflammatory activity in patients with Chronic Hepatitis B (CHB) infection.

METHODS

A total of 54 CHB patients referred for liver biopsy were enrolled in the study. Serum ACE levels were determined photometrically with a kinetic test.

RESULTS

The aspartate aminotransferase (AST), alanine aminotransferase (ALT), hepatitis B virus-deoxyribonucleic acid (HBV-DNA), histological activity index (HAI), and white blood cell counts were higher in patients with severe fibrosis, while albumin levels were low. The serum ACE levels showed a statistically significant correlation with HBV-DNA, HAI score, and ALT-AST levels.

DISCUSSION

In this study, a statistically significant relation between serum ACE levels and HAI scores was observed. This represents the first analysis to compare necroinflammation of the liver and serum ACE levels. There may be some explanations that the suppression of hepatocyte growth factor (HGF) by Angiotensin II and increased inflammatory damage might be a reason for the correlation between HAI and ACE. Serum ACE levels, HBV-DNA levels, and serum transaminase levels might be used together as noninvasive markers for the prediction of necroinflammation in CHB patients.

Effects of platelet-rich plasma and triamcinolone acetonide on interleukin-1ß-stimulated human rotator cuff-derived cells

Objectives

Triamcinolone acetonide (TA) is widely used for the treatment of rotator cuff injury because of its anti-inflammatory properties. However, TA can also produce deleterious effects such as tendon degeneration or rupture. These harmful effects could be prevented by the addition of platelet-rich plasma (PRP), however, the anti-inflammatory and anti-degenerative effects of the combined use of TA and PRP have not yet been made clear. The objective of this study was to determine how the combination of TA and PRP might influence the inflammation and degeneration of the rotator cuff by examining rotator cuff-derived cells induced by interleukin (IL)-1ß.

Methods

Rotator cuff-derived cells were seeded under inflammatory stimulation conditions (with serum-free medium with 1 ng/ml IL-1ß for three hours), and then cultured in different media: serum-free (control group), serum-free + TA (0.1mg/ml) (TA group), serum-free + 10% PRP (PRP group), and serum-free + TA (0.1mg/ml) + 10% PRP (TA+PRP group). Cell morphology, cell viability, and expression of inflammatory and degenerative mediators were assessed.

Results

Exposure to TA significantly decreased cell viability and changed the cell morphology; these effects were prevented by the simultaneous administration of PRP. Compared with the control group, expression levels of inflammatory genes and reactive oxygen species production were reduced in the TA, PRP, and TA+PRP groups. PRP significantly decreased the expression levels of degenerative marker genes.

Conclusions

The combination of TA plus PRP exerts anti-inflammatory and anti-degenerative effects on rotator cuff-derived cells stimulated by IL-1ß. This combination has the potential to relieve the symptoms of rotator cuff injury.

Cite this article: T. Muto, T. Kokubu, Y. Mifune, A. Inui, R. Sakata, Y. Harada, F. Takase, M. Kurosaka. Effects of platelet-rich plasma and triamcinolone acetonide on interleukin-1ß-stimulated human rotator cuff-derived cells. Bone Joint Res 2016;5:602–609. DOI: 10.1302/2046-3758.512.2000582.

Syndecan-1 Attenuates Lung Injury during Influenza Infection by Potentiating c-Met Signaling to Suppress Epithelial Apoptosis

RATIONALE

Syndecan-1 is a cell surface heparan sulfate proteoglycan primarily expressed in the lung epithelium. Because the influenza virus is tropic to the airway epithelium, we investigated the role of syndecan-1 in influenza infection.

OBJECTIVES

To determine the mechanism by which syndecan-1 regulates the lung mucosal response to influenza infection.

METHODS

Wild-type (WT) and Sdc1(-/-) mice were infected with a H1N1 virus (PR8) as an experimental model of influenza infection. Human and murine airway epithelial cell cultures were also infected with PR8 to study the mechanism by which syndecan-1 regulates the inflammatory response.

MEASUREMENT AND MAIN RESULTS

We found worsened outcomes and lung injury in Sdc1(-/-) mice compared with WT mice after influenza infection. Our data demonstrated that syndecan-1 suppresses bronchial epithelial apoptosis during influenza infection to limit widespread lung inflammation. Furthermore, we determined that syndecan-1 attenuated apoptosis by crosstalking with c-Met to potentiate its cytoprotective signals in airway epithelial cells during influenza infection.

CONCLUSIONS

Our work shows that cell-associated syndecan-1 has an important role in regulating lung injury. Our findings demonstrate a novel mechanism in which cell membrane-associated syndecan-1 regulates the innate immune response to influenza infection by facilitating cytoprotective signals through c-Met signaling to limit bronchial epithelial apoptosis, thereby attenuating lung injury and inflammation.

Hepatocyte growth factor as a downstream mediator of vascular endothelial growth factor-dependent preservation of growth in the developing lung

Impaired vascular endothelial growth factor (VEGF) signaling contributes to the pathogenesis of bronchopulmonary dysplasia (BPD). We hypothesized that the effects of VEGF on lung structure during development may be mediated through its downstream effects on both endothelial nitric oxide synthase (eNOS) and hepatocyte growth factor (HGF) activity, and that, in the absence of eNOS, trophic effects of VEGF would be mediated through HGF signaling. To test this hypothesis, we performed an integrative series of in vitro (fetal rat lung explants and isolated fetal alveolar and endothelial cells) and in vivo studies with normal rat pups and eNOS(-/-) mice. Compared with controls, fetal lung explants from eNOS(-/-) mice had decreased terminal lung bud formation, which was restored with recombinant human VEGF (rhVEGF) treatment. Neonatal eNOS(-/-) mice were more susceptible to hyperoxia-induced inhibition of lung growth than controls, which was prevented with rhVEGF treatment. Fetal alveolar type II (AT2) cell proliferation was increased with rhVEGF treatment only with mesenchymal cell (MC) coculture, and these effects were attenuated with anti-HGF antibody treatment. Unlike VEGF, HGF directly stimulated isolated AT2 cells even without MC coculture. HGF directly stimulates fetal pulmonary artery endothelial cell growth and tube formation, which is attenuated by treatment with JNJ-38877605, a c-Met inhibitor. rHGF treatment preserves alveolar and vascular growth after postnatal exposure to SU-5416, a VEGF receptor inhibitor. We conclude that the effects of VEGF on AT2 and endothelial cells during lung development are partly mediated through HGF-c-Met signaling and speculate that reciprocal VEGF-HGF signaling between epithelia and endothelia is disrupted in infants who develop BPD.

Therapeutic Potential of HGF-Expressing Human Umbilical Cord Mesenchymal Stem Cells in Mice with Acute Liver Failure

Human umbilical cord-derived mesenchymal stem cells (UCMSCs) are particularly attractive cells for cellular and gene therapy in acute liver failure (ALF). However, the efficacy of this cell therapy in animal studies needs to be significantly improved before it can be translated into clinics. In this study, we investigated the therapeutic potential of UCMSCs that overexpress hepatocyte growth factor (HGF) in an acetaminophen-induced acute liver failure mouse model. We found that the HGF-UCMSC cell therapy protected animals from acute liver failure by reducing liver damage and prolonging animal survival. The therapeutic effect of HGF-UCMSCs was associated with the increment in serum glutathione (GSH) and hepatic enzymes that maintain redox homeostasis, including γ-glutamylcysteine synthetase (γ-GCS), superoxide dismutase (SOD), and catalase (CAT). Immunohistochemical staining confirmed that HGF-UCMSCs were mobilized to the injured areas of the liver. Additionally, HGF-UCMSCs modulated apoptosis by upregulating the antiapoptotic Bcl2 and downregulating proapoptotic genes, including Bax and TNFα. Taken together, these data suggest that ectopic expression of HGF in UCMSCs protects animals from acetaminophen-induced acute liver failure through antiapoptosis and antioxidation mechanisms.

Hepatocyte Growth Factor Isoforms in Tissue Repair, Cancer, and Fibrotic Remodeling

Hepatocyte growth factor (HGF), also known as scatter factor (SF), is a pleotropic factor required for normal organ development during embryogenesis. In the adult, basal expression of HGF maintains tissue homeostasis and is up-regulated in response to tissue injury. HGF expression is necessary for the proliferation, migration, and survival of epithelial and endothelial cells involved in tissue repair in a variety of organs, including heart, lung, kidney, liver, brain, and skin. The administration of full length HGF, either as a protein or using exogenous expression methodologies, increases tissue repair in animal models of tissue injury and increases angiogenesis. Full length HGF is comprised of an N-terminal hairpin turn, four kringle domains, and a serine protease-like domain. Several naturally occurring alternatively spliced isoforms of HGF were also identified. The NK1 variant contains the N-terminal hairpin and the first kringle domain, and the NK2 variant extends through the second kringle domain. These alternatively spliced forms of HGF activate the same receptor, MET, but they differ from the full length protein in their cellular activities and their biological functions. Here, we review the species-specific expression of the HGF isoforms, their regulation, the signal transduction pathways they activate, and their biological activities.

Chitinase 3-like 1 suppresses injury and promotes fibroproliferative responses in Mammalian lung fibrosis

Epithelial injury, alternative macrophage accumulation, and fibroproliferation coexist in the lungs of patients with idiopathic pulmonary fibrosis (IPF). Chitinase 3-like 1 (CHI3L1) is a prototypic chitinase-like protein that has been retained over species and evolutionary time. However, the regulation of CHI3L1 in IPF and its ability to regulate injury and/or fibroproliferative repair have not been fully defined. We demonstrated that CHI3L1 levels were elevated in patients with IPF. High levels of CHI3L1 are associated with progression--as defined by lung transplantation or death--and with scavenger receptor-expressing circulating monocytes in an ambulatory IPF population. In preterminal acute exacerbations of IPF, CHI3L1 levels were reduced and associated with increased levels of apoptosis. We also demonstrated that in bleomycin-treated mice, CHI3L1 expression was acutely and transiently decreased during the injury phase and returned toward and eventually exceeded baseline levels during the fibrotic phase. In this model, CHI3L1 played a protective role in injury by ameliorating inflammation and cell death, and a profibrotic role in the repair phase by augmenting alternative macrophage activation, fibroblast proliferation, and matrix deposition. Using three-dimensional culture system of a human fibroblast cell line, we found that CHI3L1 is sufficient to induce low grade myofibroblast transformation. In combination, these studies demonstrate that CHI3L1 is stimulated in IPF, where it represents an attempt to diminish injury and induce repair. They also demonstrate that high levels of CHI3L1 are associated with disease progression in ambulatory patients and that a failure of the CHI3L1 antiapoptotic response might contribute to preterminal disease exacerbations.

Hepatocyte growth factor is an attractive target for the treatment of pulmonary fibrosis

INTRODUCTION

Pulmonary fibrosis (PF) is a progressive fatal disorder and is characterized by alveolar epithelial injury, myofibroblast proliferation, and extracellular matrix remodeling, resulting in irreversible distortion of lung's architecture. Available therapies are associated with side effects and show restricted efficacy. Therefore, there is an urgent need to find a therapeutic solution to PF. Therapeutic strategies interfering myofibroblast expansion, apoptosis of epithelial and endothelial cells might be beneficial for treatment of PF. Hepatocyte growth factor (HGF), a pleiotropic growth factor, plays an important role in lung development, inflammation, repair, and regeneration. In animal model of PF, administration of recombinant HGF protein or ectopic HGF expression ameliorates fibrosis.

AREAS COVERED

The focus of this review is to highlight HGF as a promising therapeutic approach for the treatment of PF. The review discusses the currently available treatment option for PF as well as highlights the possible beneficial effect of HGF as a drug target.

EXPERT OPINION

HGF with its anti-fibrotic effect provides a promising new therapeutic approach by protecting lung from fibrotic remodeling and also promoting normal regeneration of lung. The development of HGF mimetics may provide a potential attractive therapy for treatment of this devastating and complex disease.

HGF mediates the anti-inflammatory effects of PRP on injured tendons

Platelet-rich plasma (PRP) containing hepatocyte growth factor (HGF) and other growth factors are widely used in orthopaedic/sports medicine to repair injured tendons. While PRP treatment is reported to decrease pain in patients with tendon injury, the mechanism of this effect is not clear. Tendon pain is often associated with tendon inflammation, and HGF is known to protect tissues from inflammatory damages. Therefore, we hypothesized that HGF in PRP causes the anti-inflammatory effects. To test this hypothesis, we performed in vitro experiments on rabbit tendon cells and in vivo experiments on a mouse Achilles tendon injury model. We found that addition of PRP or HGF decreased gene expression of COX-1, COX-2, and mPGES-1, induced by the treatment of tendon cells in vitro with IL-1β. Further, the treatment of tendon cell cultures with HGF antibodies reduced the suppressive effects of PRP or HGF on IL-1β-induced COX-1, COX-2, and mPGES-1 gene expressions. Treatment with PRP or HGF almost completely blocked the cellular production of PGE2 and the expression of COX proteins. Finally, injection of PRP or HGF into wounded mouse Achilles tendons in vivo decreased PGE2 production in the tendinous tissues. Injection of platelet-poor plasma (PPP) however, did not reduce PGE2 levels in the wounded tendons, but the injection of HGF antibody inhibited the effects of PRP and HGF. Further, injection of PRP or HGF also decreased COX-1 and COX-2 proteins. These results indicate that PRP exerts anti-inflammatory effects on injured tendons through HGF. This study provides basic scientific evidence to support the use of PRP to treat injured tendons because PRP can reduce inflammation and thereby reduce the associated pain caused by high levels of PGE2.

Overexpression of HGF transgene attenuates renal inflammatory mediators, Na(+)-ATPase activity and hypertension in spontaneously hypertensive rats

Renal inflammation and oxidative stress are constantly present in experimental hypertension. Since the spontaneously hypertensive rat (SHR) has reduced levels of hepatocyte growth factor (HGF), which suppresses the activation of the proinflammatory nuclear transcription factor kappa B (NF-κB), we speculated that HGF deficiency could play a key role in the pathogenesis of hypertension in the SHR. To test this hypothesis we increased HGF in the SHR by HGF gene delivery. We found that kidneys of 15-week-old SHR had an important reduction in HGF mRNA and protein expression. Adult SHRs were randomly assigned to receive weekly hydrodynamic injection (1mg/kg) of a naked plasmid containing human HGF (hHGF) gene associated with a cytomegalovirus promoter (pCMV-HGF) or empty vector (pcDNA3.1) during 6weeks. WKY rats treated with pcDNA3.1 and pCMV-HGF served as controls. The kidneys in the hypertensive SHR untreated and treated with the empty vector had increased NF-κB activation, elevated mRNA and protein expression of RANTES, MCP-1 and IL-6 and increased oxidative stress. Activity of Na(+)-ATPase was increased while activity of Na(+), K(+)-ATPase was normal. hHGF gene therapy normalized renal NF-κB activity, proinflammatory cytokines, antioxidant status (GSH, SOD and CAT), Na(+)-ATPase activity, reduced renal injury and ameliorated hypertension. Our results suggest that reduction in HGF production plays a major role in the pathogenesis of hypertension in the SHR and increasing HGF is a potential therapeutic target in the treatment of hypertension.

Inflammatory cytokines regulate endothelial cell survival and tissue repair functions via NF-κB signaling

Inflammation contributes to the development of fibrotic and malignant diseases. We assessed the ability of inflammatory cytokines to modulate endothelial cell survival and functions related to tissue repair/remodeling. Treatment with interleukin (IL)-1β or tumor necrosis factor (TNF)-α (2 ng/mL) led to human pulmonary artery endothelial cells becoming spindle-shaped fibroblast-like cells. However, immunoblot and DNA microarray showed no change in most endothelial and mesenchymal markers. In the presence of IL-1β or TNF-α, cells were resistant to apoptosis induced by deprivation of serum and growth factor, and were more migratory. In addition, cells treated with IL-1β or TNF-α contracted collagen gels more robustly. In contrast, transforming growth factor-β1 did not induce these responses. RNA interference targeting nuclear factor (NF)-κB p65 blocked the effects of IL-1β or TNF-α on cell morphologic change, survival, migration, and collagen gel contraction. These results suggest that endothelial cells may contribute to tissue repair/remodeling via the NF-κB signaling in a milieu of airway inflammation.

Hepatocyte growth factor in lung repair and pulmonary fibrosis

Pulmonary remodeling is characterized by the permanent and progressive loss of the normal alveolar architecture, especially the loss of alveolar epithelial and endothelial cells, persistent proliferation of activated fibroblasts, or myofibroblasts, and alteration of extracellular matrix. Hepatocyte growth factor (HGF) is a pleiotropic factor, which induces cellular motility, survival, proliferation, and morphogenesis, depending upon the cell type. In the adult, HGF has been demonstrated to play a critical role in tissue repair, including in the lung. Administration of HGF protein or ectopic expression of HGF has been demonstrated in animal models of pulmonary fibrosis to induce normal tissue repair and to prevent fibrotic remodeling. HGF-induced inhibition of fibrotic remodeling may occur via multiple direct and indirect mechanisms including the induction of cell survival and proliferation of pulmonary epithelial and endothelial cells, and the reduction of myofibroblast accumulation.

Hepatocyte growth factor in lung repair and pulmonary fibrosis

Pulmonary remodeling is characterized by the permanent and progressive loss of the normal alveolar architecture, especially the loss of alveolar epithelial and endothelial cells, persistent proliferation of activated fibroblasts, or myofibroblasts, and alteration of extracellular matrix. Hepatocyte growth factor (HGF) is a pleiotropic factor, which induces cellular motility, survival, proliferation, and morphogenesis, depending upon the cell type. In the adult, HGF has been demonstrated to play a critical role in tissue repair, including in the lung. Administration of HGF protein or ectopic expression of HGF has been demonstrated in animal models of pulmonary fibrosis to induce normal tissue repair and to prevent fibrotic remodeling. HGF-induced inhibition of fibrotic remodeling may occur via multiple direct and indirect mechanisms including the induction of cell survival and proliferation of pulmonary epithelial and endothelial cells, and the reduction of myofibroblast accumulation.

Novel therapeutic strategies for acute lung injury induced by lung damaging agents: the potential role of growth factors as treatment options

The increasing threat from terrorism has brought attention to the possible use of toxic industrial compounds (TICs) and other lung-damaging agents as weapons against civilian populations. The way in which these agents could be used favours the development of generic countermeasures. Improved medical countermeasures would increase survivability and improve the quality of recovery of lung damaged casualties. It is evident that there is a dearth of therapeutic regimes available to treat those forms of lung damage that currently require intensive care management. It is quite possible that mass casualties from a terrorist incident or major industrial accident involving the release of large quantities of inhaled TICs would place a severe burden on already scarce intensive care facilities. The development of effective pharmacological approaches to assist the recovery of casualties suffering from acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) may improve the prognosis of such patients (which is currently poor) and would ideally be used as a means of preventing subjects from developing the pulmonary oedema characteristic of ALI/ARDS. Many promising candidate pharmacological treatments have been evaluated for the treatment of ALI/ARDS, but their clinical value is often debatable. Thus, despite improvements in ventilation strategies, pharmacological intervention for ALI/ARDS remains problematical. A new approach is clearly required for the treatment of patients with severely compromised lungs. Whilst the pathology of ALI/ARDS associated with exposure to a variety of agents is complex, numerous experimental studies suggest that generic therapeutic intervention directed at approaches that aim to upregulate repair of the damaged alveolar blood/air barrier of the lung may be of value, particularly with respect to chemical-induced injury. To this end, keratinocyte growth factor (KGF), epithelial growth factor (EGF) and basic fibroblast growth factor (bFGF) are emerging as the most important candidates. Hepatocyte growth factor (HGF) does not have epithelial specificity for lung tissue. However, the enhanced effects of combinations of growth factors, such as the synergistic effect of HGF upon vascular endothelial growth factor (VEGF)-mediated endothelial cell activity, and the combined effect of HGF and KGF in tissue repair should be investigated, particularly as the latter pair of growth factors are frequently implicated in processes associated with the repair of lung damage. Synergistic interactions also occur between trefoil factor family (TFF) peptides and growth factors such as EGF. TFF peptides are most likely to be of value as a short term therapeutic intervention strategy in stimulating epithelial spreading activities which allow damaged mucosal surfaces to be rapidly covered by epithelial cells.

Life-sparing effect of human cord blood-mesenchymal stem cells in experimental acute kidney injury

In search for new sources of mesenchymal stem cells (MSCs) for renal repair in acute kidney injury (AKI), we investigated the potential of human cord blood (CB)-MSCs to cure mice with AKI. Infusion of CB-MSCs in immunodeficient mice with cisplatin-induced AKI ameliorated both renal function and tubular cell injury, and prolonged survival. Transplanted CB-MSCs localized in peritubular areas, limited capillary alterations and neutrophil infiltration. Apoptosis reduced and tubular cell proliferation increased by virtue of stem cell capacity to produce growth factors. The reno-protective effect of CB-MSCs was further confirmed by their ability to inhibit oxidative damage and to induce the prosurvival factor Akt in tubular cells. The evidence that CB-MSCs in vitro increased the production of growth factors and inhibited IL-1 beta and TNFalpha synthesis when cocultured with damaged proximal tubular cells indicates a regenerative and anti-inflammatory action of stem cell treatment. Altogether these results highlight the potential of human CB-MSCs as future cell therapy for testing in human AKI.

Hepatocyte growth factor protects hepatocytes against oxidative injury induced by ethanol metabolism

Hepatocyte growth factor (HGF) is involved in many cellular responses, such as mitogenesis and apoptosis protection; however, its effect against oxidative injury induced by ethanol metabolism is not well understood. The aim of this work was to address the mechanism of HGF-induced protection against ethanol-generated oxidative stress damage in the human cell line VL-17A (cytochrome P450 2E1/alcohol dehydrogenase-transfected HepG2 cells). Cells were pretreated with 50 ng/ml HGF for 12 h and then treated with 100 mM ethanol for 0-48 h. Some parameters of oxidative damage were evaluated. We found that ethanol induced peroxide formation (3.3-fold) and oxidative damage as judged by lipid peroxidation (5.4-fold). Damage was prevented by HGF. To address the mechanisms of HGF-induced protection we investigated the cellular antioxidant system. We found that HGF increased the GSH/GSSG ratio, as well as SOD1, catalase, and gamma-glutamylcysteine synthetase expression. To explore the signaling pathways involved in this process, VL-17A cells were pretreated with inhibitors against PI3K, Akt, and NF-kappaB. We found that all treatments decreased the expression of the antioxidant enzymes, thus abrogating the HGF-induced protection against oxidative stress. Our results demonstrate that HGF protects cells from the oxidative damage induced by ethanol metabolism by a mechanism driven by NF-kappaB and PI3K/Akt signaling.

Use of Heparin in Women With Early and Late Miscarriages With and Without Thrombophilia

Objective: In women with a history of recurrent miscarriage, the risk of miscarriage in a subsequent pregnancy is about 30% to 40%. In patients with thrombophilia, the risk is even higher. Placental thrombosis has been found in women with unexplained recurrent miscarriage independent of thrombophilia. In addition, proinflammatory changes, for example, altered Th1 to Th2 cytokine ratio and complement activation, have been repeatedly demonstrated in these women. Because of the fact that heparin has both anticoagulative and anti-inflammatory effects, the current study evaluated the efficacy of low-molecular-weight heparin (LMWH) in unexplained abortions. Study Design: A total of 164 women with unexplained early and late miscarriages presented in our hemostaseological clinic for thrombophilia screening. For these 164 women, 82 subsequent pregnancies in 79 patients were treated with subcutaneous LMWH independently of thrombophilia. In 54/82 unselected pregnancies, 100 mg aspirin was administered in addition to LMWH. Two patients were excluded due to termination of pregnancy. Results: Overall, 83.8% (67/80) of pregnancies resulted in live births. In 22/79 women (27.8%), thrombophilia markers were positive. Most noteworthy, patients with thrombophilia markers had live births at a similar frequency as patients without those parameters. No severe side effects of LMWH were seen. Conclusions: Our data support the notion that LMWH is efficacious in patients with recurrent abortions and thrombophilia. We demonstrated the same effect of LMWH in women with unexplained abortions without thrombophilia. The potential mechanism of action of LMWH in early and late abortions warrants further study.

In Vitro Assessment of Apoptosis and Necrosis Following Cold Storage in a Human Airway Cell Model

As advances in medical technology improve the efficacy of cell and tissue transplantation, a void remains in our knowledge base as to the specific molecular responses of cells to low-temperature storage. While much focus has been given to solution formulation for tissue perfusion during storage, investigations into cold exposure-induced complex molecular changes remain limited. The intent of this study was to quantify the levels of cell death following hypothermic storage in a lung cell model, establishing a foundation for future in-depth molecular analysis. Normal human lung fibroblasts (IMR-90) were stored for 1 day or 2 days and small airway epithelial cells (SAEC) were stored for 5 days or 7 days at 4°C in complete media, ViaSpan, or ViaSpan + pan-caspase (VI) inhibitor. (Poststorage viability was assessed for 3 days using alamarBlue(™).) Sample analysis revealed that IMR-90 cells stored in ViaSpan remained 80% (±9) viable after 1 day of storage and 21% (±7) viable after 2 days of storage. SAEC cells stored in ViaSpan remained 81% (±5) viable after 5 days and 28% (±7) after 7 days. Microfluidic flow cytometry analysis of the apoptotic and necrotic populations in the ViaSpan-stored samples revealed that in the IMR-90 cells stored for 2 days, 7% of the population was apoptotic at 4-h poststorage, while ∼70% was identified as necrotic. Analysis of the SAEC cell system following 7 days of ViaSpan storage revealed an apoptotic peak of 19% at 4-h poststorage and a corresponding necrotic peak of 19%. Caspase inhibition during hypothermic storage increased viability 33% for IMR-90 and 25% for SAEC. Data revealed a similar pattern of cell death, through both apoptosis and necrosis, once the onset of cold storage failure began, implying a potential conserved mechanism of cold-induced cell death. These data highlight the critical need for a more in-depth understanding of the molecular changes that occur as a result of cold exposure in cells and tissues.

Hepatocyte growth factor improves viability after H2O2-induced toxicity in bile duct epithelial cells

Intracellular defence mechanisms against oxidative stress may play an important role in the progression of liver diseases, including cholangiopathies. The multifunctional anti-apoptotic hepatocyte growth factor (HGF) has been suggested to have antioxidant functions. The effect of HGF upon cell viability, the generation of ROS, the expression of genes that play a role in ROS defence, and the activation of caspase-3 were measured in bile duct epithelial (BDE) cells in the presence or absence of H(2)O(2). HGF reduced H(2)O(2)-induced loss of viability, diminished H(2)O(2)-mediated ROS generation and abrogated H(2)O(2)-triggered changes in GSH/GSSG ratio. Furthermore, HGF increased the gene-expression of gamma-glutamylcysteine synthetase (GCLC) and glutathione reductase (GSR), while no effect was seen upon the gene-expression of superoxide dismutase 1 (SOD1), catalase (CAT), glutathione peroxidase (GPX1), and glutathione synthetase (GSR). Finally, HGF diminished the proteolytical activation of the key mediator of apoptosis (caspase-3) after H(2)O(2) exposure. Together, HGF may improve viability in bile duct epithelia cells after H(2)O(2) induced toxicity by proliferation, strengthening the intrinsic antioxidant defences, and/or by an attenuation of apoptosis. These in vitro results support the evaluation of HGF as antioxidative factor in hepatobiliary pathologies.

Locally overexpressing hepatocyte growth factor prevents post-ischemic heart failure by inhibition of apoptosis via calcineurin-mediated pathway and angiogenesis

BACKGROUND

Myocardial infarction is a significant cause of heart failure. Currently, therapies are limited and novel revascularization methods may play a role. We investigated the effects of hepatocyte growth factor (HGF) expressed by bone marrow-derived mesenchymal stem cells (MSCs) on post-ischemic heart failure.

METHODS

Four weeks after myocardial infarction (MI), Sprague Dawley rats were randomly divided into saline control group, MSC-GFP group, MSC-HGF group, and MSC-HGF+CsA group. After another 4 weeks, hearts were analyzed for ventricular geometry, myocardial function, angiogenesis and endothelial cell density, apoptosis and the expression of calcineurin, Akt, and Bcl-2 protein.

RESULTS

In MSC-HGF group, rats exhibited better LV systolic and diastolic function compared with other groups after 8 weeks of MI. Angiogenesis was significantly enhanced by HGF through inducing proliferation of endothelial cells. The effects of HGF on apoptosis were associated with the expression level of calcineurin protein.

CONCLUSIONS

Our findings suggest that overexpression of HGF improved ischemic cardiac function through angiogenesis and reduction of apoptosis partly mediated by upregulation of calcineurin.

Selenium deficiency alters epithelial cell morphology and responses to influenza

It is unknown whether nutritional deficiencies affect the morphology and function of structural cells, such as epithelial cells, and modify the susceptibility to viral infections. We developed an in vitro system of differentiated human bronchial epithelial cells (BEC) grown either under selenium-adequate (Se+) or selenium-deficient (Se-) conditions, to determine whether selenium deficiency impairs host defense responses at the level of the epithelium. Se- BECs had normal SOD activity, but decreased activity of the selenium-dependent enzyme GPX1. Interestingly, catalase activity was also decreased in Se- BECs. Both Se- and Se+ BECs differentiated into a mucociliary epithelium; however, Se- BEC demonstrated increased mucus production and increased Muc5AC mRNA levels. This effect was also seen in Se+ BEC treated with 3-aminotriazole, an inhibitor of catalase activity, suggesting an association between catalase activity and mucus production. Both Se- and Se+ were infected with influenza A/Bangkok/1/79 and examined 24 h postinfection. Influenza-induced IL-6 production was greater while influenza-induced IP-10 production was lower in Se- BECs. In addition, influenza-induced apoptosis was greater in Se- BEC as compared to the Se+ BECs. These data demonstrate that selenium deficiency has a significant impact on the morphology and influenza-induced host defense responses in human airway epithelial cells.

HGF protects rat mesangial cells from high-glucose-mediated oxidative stress

BACKGROUND

Oxidative stress has been considered to be a common pathogenetic factor of diabetic nephropathy. Recent observations suggested that hepatocyte growth factor (HGF) was an antioxidant growth factor; thus, its renoprotective effects in diabetic nephropathy might be related to antioxidant mechanism. The aim of the present study was to evaluate whether HGF could prevent rat mesangial cells (RMC) from high-glucose-mediated oxidative stress and explore its relevant mechanism.

METHODS

RMC were cultured in 5.6 mM (NG) or 30 mM (HG) glucose in the absence or presence of HGF (20 ng/ml) and c-met inhibitor SU11274 (5 microM) for 24 h.

RESULTS

c-met expression in HG was markedly increased. Enhanced oxidative stress was observed in HG as evidenced by elevated reactive oxygen species and malondialdehyde levels and decreased glutathione level, which was markedly attenuated by HGF. HGF also inhibited HG-induced p22(phox) and aldose reductase upregulation and prevented HG-reduced glutamate-cysteine ligase catalytic subunit (GCLC) expression through inhibiting USF binding to negative regulatory region of GCLC promoter. Reduced glucose-6-phosphate dehydrogenase activity and expression in RMC by HG was rescued by HGF.

CONCLUSION

HGF could function as an antioxidant factor and protect against HG-mediated oxidative stress by enhancing ROS scavenging and suppressing ROS production.

Inference of disease-related molecular logic from systems-based microarray analysis

Computational analysis of gene expression data from microarrays has been useful for medical diagnosis and prognosis. The ability to analyze such data at the level of biological modules, rather than individual genes, has been recognized as important for improving our understanding of disease-related pathways. It has proved difficult, however, to infer pathways from microarray data by deriving modules of multiple synergistically interrelated genes, rather than individual genes. Here we propose a systems-based approach called Entropy Minimization and Boolean Parsimony (EMBP) that identifies, directly from gene expression data, modules of genes that are jointly associated with disease. Furthermore, the technique provides insight into the underlying biomolecular logic by inferring a logic function connecting the joint expression levels in a gene module with the outcome of disease. Coupled with biological knowledge, this information can be useful for identifying disease-related pathways, suggesting potential therapeutic approaches for interfering with the functions of such pathways. We present an example providing such gene modules associated with prostate cancer from publicly available gene expression data, and we successfully validate the results on additional independently derived data. Our results indicate a link between prostate cancer and cellular damage from oxidative stress combined with inhibition of apoptotic mechanisms normally triggered by such damage.

Effect of IL-10 on the expression of HSC growth factors in hepatic fibrosis rat

AIM: To study the effect of IL-10 on the expression of growth factors - transforming growth factor-β1 (TGF-β1), epidermal growth factor (EGF), hepatocyte growth factor (HGF)and platelet-derived growth factor (PDGF) of hepatic stellate cells (HSCs) of hepatic fibrosis rat and the anti-fibrogenic role of exogenous IL-10.

METHODS: Hepatic fibrosis was induced by CCl4 administration intra-peritoneally. Sixty clean male Sprague-Dawley (SD) rats were randomly divided into three groups: normal control group (GN, 8 rats), hepatic fibrosis model group (GC, 28 rats) and IL-10 treated group (GI, 24 rats). At the beginning of the 7^th and 11^th wk, rats in each group were routinely perfused with pronase E and type IV collag-enase through a portal vein catheter and the suspension obtained from the liver was spun by centrifugation with 11% Nycodenz density gradient to isolate HSCs. Histological examination was used to determine the degree of hepatic fibrosis. RT-PCR was employed to analyze mRNA expression from freshly isolated cells. Immunocytochemistry was performed to detect protein expression in primary cultured HSCs.

RESULTS: Rat hepatic fibrosis was developed with the increase of injection frequency of CCl4, and HSCs were successfully isolated. At the 7^th and 11^th wk, TGF-β1, EGF, and HGF mRNA in GC increased obviously compared with GN (P = 0.001/0.042, 0.001/0.001, 0.001/0.001) and GI (P = 0.001/0.007, 0.002/0.001, 0.001/0.001). For TGF-β1, no difference was observed between GI and GN. For EGF, mRNA level in GI increased compared with GN during the 7^th wk (P = 0.005) and 11^th wk (P = 0.049). For HGF, mRNA level in GI decreased compared with GN at the 7^th wk (P = 0.001) and 11^th wk (P = 0.021). Between these two time points, TGF-β1 expression at the 7^th wk was higher than that of the 11^th wk (P = 0.049), but for EGF, the former was lower than the latter (P = 0.022). As for PDGF mRNA, there was no significant difference between these groups, but difference seemed to exist in protein levels. Results by immunocytochemistry of TGF-β1 and EGF were paralleled with the above findings.

CONCLUSION: The expression of TGF-β1, EGF and HGF increased in HSC of hepatic fibrosis rat and decreased after treatment with IL-10. IL-10 plays an anti-fibrogenic role by suppressing growth factors expression.

Effect of donor treatment with heparinoids on graft function after intraportal transplantation of a marginal islet mass: An experimental study

Heparinoids interact with factors that are involved in ischemia-reperfusion injury and thus may prevent organ injury. We therefore studied the effects on subsequent intraportal islet transplantation of systemic administration of unfractionated and N-desulphated heparin to donors prior to pancreatectomy. Donor rats were given an intravenous injection of either heparin (1.3 mg/kg or 13.3 mg/kg; 200 U/kg or 2000 U/kg, respectively) or N-desulphated heparin (50 mg/kg; approximately 5 U/kg) at 5 to 10 minutes prior to pancreas procurement. Five hundred freshly isolated islets were injected intraportally into syngeneic male Lewis recipients that had developed streptozotocin-induced diabetes. Blood glucose and body weight were monitored for 5 weeks thereafter. Rats transplanted with islets from donors given high dose heparin showed a fall in blood glucose from 25.1 +/- 1.4 to 11.0 +/- 2.7 mmol/L (P <.01) with 60% of animals euglycemic within the first week. In contrast, the controls, did not show a fall in glucose levels at 1 week and none had become euglycaemic. Normalization of glycemia was slower in recipients of islets from animals treated with the lower dose of heparin. Results were intermediate with islets from donors given N-desulphated heparin. Nevertheless, all heparinoids used in this study caused more than a doubling of the number of animals achieving normoglycemia by 3 to 4 weeks. We hypothesize that pretreatment of the donor with heparin protects islet integrity during procurement and isolation and hence accelerates islet engraftment and remodelling. Since the effect was seen with N-desulphated heparin, which has negligible anticoagulant properties, we believe the mechanism to be independent of the anticoagulant activity.