Changes of gene expression after bone marrow cell transfusion in rats with monocrotaline-induced pulmonary hypertension

Cell Tracking Suggests Pathophysiological and Therapeutic Role of Bone Marrow Cells in Sugen5416/Hypoxia Rat Model of Pulmonary Arterial Hypertension

BACKGROUND

The mechanism of vascular remodelling in pulmonary arterial hypertension (PAH) remains unclear. Hence, defining the origin of cells constituting intractable vascular lesions in PAH is expected to facilitate therapeutic progress. Herein, we aimed to evaluate the origin of intractable vascular lesions in PAH rodent models via bone marrow (BM) and orthotopic lung transplantation (LT).

METHODS

To trace BM-derived cells, we prepared chimeric rats transplanted with BM cells from green fluorescent protein (GFP) transgenic rats. Male rats were transplanted with lungs obtained from female rats and vice versa. Pulmonary hypertension was induced in the transplanted rats via Sugen5416 treatment and subsequent chronic hypoxia (Su/Hx).

RESULTS

In the chimeric Su/Hx models, GFP-positive cells were observed in the pulmonary vascular area. Moreover, the right ventricular systolic pressure was significantly lower compared with wild-type Su/Hx rats without BM transplantation (P = 0.009). PAH suppression was also observed in rats that received allograft transplanted BM transplantation. In male rats that received LT and Su/Hx, BM-derived cells carrying the Y chromosome were also detected in neointimal occlusive lesions of the transplanted lungs received from female rats.

CONCLUSIONS

BM-derived cells participate in pulmonary vascular remodelling in the Su/Hx rat model, whereas BM transplantation may contribute to suppression of development of PAH.

Intranasal delivery of human umbilical cord Wharton's jelly mesenchymal stromal cells restores lung alveolarization and vascularization in experimental bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a devastating lung condition that develops in premature newborns exposed to prolonged mechanical ventilation and supplemental oxygen. Significant morbidity and mortality are associated with this costly disease and effective therapies are limited. Mesenchymal stem/stromal cells (MSCs) are multipotent cells that can repair injured tissue by secreting paracrine factors known to restore the function and integrity of injured lung epithelium and endothelium. Most preclinical studies showing therapeutic efficacy of MSCs for BPD are administered either intratracheally or intravenously. The purpose of this study was to examine the feasibility and effectiveness of human cord tissue-derived MSC administration given via the intranasal route. Human umbilical cord tissue MSCs were isolated, characterized, and given intranasally (500 000 cells per 20 μL) to a hyperoxia-induced rat model of BPD. Lung alveolarization, vascularization, and pulmonary vascular remodeling were restored in animals receiving MSC treatment. Gene and protein analysis suggest the beneficial effects of MSCs were attributed, in part, to a concerted effort targeting angiogenesis, immunomodulation, wound healing, and cell survival. These findings are clinically significant, as neonates who develop BPD have altered alveolar development, decreased pulmonary vascularization and chronic inflammation, all resulting in impaired tissue healing. Our study is the first to report the intranasal delivery of umbilical cord Wharton's jelly MSCs in experimental BPD is feasible, noninvasive, and an effective route that may bear clinical applicability.

Regenerative cell therapy for pulmonary arterial hypertension in animal models: a systematic review

Background

Pulmonary arterial hypertension (PAH) is a rare disease characterized by widespread loss of the pulmonary microcirculation and elevated pulmonary arterial pressures leading to pathological right ventricular remodeling and ultimately right heart failure. Regenerative cell therapies could potentially restore the effective lung microcirculation and provide a curative therapy for PAH. The objective of this systematic review was to compare the efficacy of regenerative cell therapies in preclinical models of PAH.

Methods

A systematic search strategy was developed and executed. We included preclinical animal studies using regenerative cell therapy in experimental models of PAH. Primary outcomes were right ventricular systolic pressure (RVSP) and mean pulmonary arterial pressure (mPAP). The secondary outcome was right ventricle/left ventricle + septum weight ratio (RV/LV+S). Pooled effect sizes were undertaken using random effects inverse variance models. Risk of bias and publication bias were assessed.

Results

The systematic search yielded 1285 studies, of which 44 met eligibility criteria. Treatment with regenerative cell therapy was associated with decreased RVSP (SMD − 2.10; 95% CI − 2.59 to − 1.60), mPAP (SMD − 2.16; 95% CI − 2.97 to − 1.35), and RV/LV+S (SMD − 1.31, 95% CI − 1.64 to − 0.97). Subgroup analysis demonstrated that cell modification resulted in greater reduction in RVSP. The effects on RVSP and mPAP remained statistically significant even after adjustment for publication bias. The majority of studies had an unclear risk of bias.

Conclusions

Preclinical studies of regenerative cell therapy demonstrated efficacy in animal models of PAH; however, future studies should consider incorporating design elements to reduce the risk of bias.

Systematic review registration

Suen CM, Zhai A, Lalu MM, Welsh C, Levac BM, Fergusson D, McIntyre L and Stewart DJ. Efficacy and safety of regenerative cell therapy for pulmonary arterial hypertension in animal models: a preclinical systematic review protocol. Syst Rev. 2016;5:89.

Trial registration

CAMARADES-NC3Rs Preclinical Systematic Review & Meta-analysis Facility (SyRF). http://syrf.org.uk/protocols/. Syst Rev 5:89, 2016

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1172-6) contains supplementary material, which is available to authorized users.

Efficacy of stem cell therapy for pulmonary arterial hypertension: a systematic review and meta-analysis of preclinical studies

Background

Despite significant progress in drug treatment, the prognosis of patients with advanced pulmonary arterial hypertension (PAH) remains extremely poor. Many preclinical studies have reported the efficacy of stem cell (SC) therapy for PAH; however, this approach remains controversial. The aim of this systematic review and meta-analysis is to assess the potential efficacy of SC therapy for PAH.

Methods

The Medline, EMBASE, Cochrane Library, and Web of Science databases were searched from inception to August 12, 2018. Preclinical studies that evaluated the use of SC therapy for PAH were included. The primary outcome was pulmonary haemodynamics, as assessed by measurement of the right ventricular systolic pressure (RVSP), mean pulmonary arterial pressure (mPAP), and/or mean right ventricle pressure (mRVP). The secondary outcomes included the weight ratio of the right ventricle to the left ventricle plus septum (RV/LV+S), the right ventricle to body weight ratio (RV/BW), the percentage of pulmonary arteriole area index (WA), and/or the percentage of medial wall thickness of the pulmonary arteriole (WT). The quality of outcomes was evaluated using the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) bias risk tool. The inverse-variance method with random-effects modelling was used to calculate pooled weighted mean differences (WMDs) and 95% CIs. Statistical analysis was performed with STATA 14.0.

Results

Twenty-eight eligible articles (722 animals) were included. SC therapy reduced the pooled WMDs (95% CIs) of RVSP, mPAP, mRVP, RV/LV+S, RV/BW, WA, and WT for animals with PAH, with values of − 14.12 (− 14.63, − 13.61), − 11.86 (− 12.35, − 11.36), − 17.33 (− 18.10, − 16.56), − 0.10 (− 0.10, − 0.09), 0.23 (0.21, 0.24), − 13.66 (− 15.71, − 11.62), and − 7.96 (− 7.99, − 7.93), respectively.

Conclusions

SC therapy is effective for PAH in preclinical studies. These results may help to standardise preclinical animal studies and provide a theoretical basis for clinical trial design in the future.

Systematic review registration

PROSPERO (http://www.crd.york.ac.uk/PROSPERO).

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1162-8) contains supplementary material, which is available to authorized users.

Mitochondria in mesenchymal stem cell biology and cell therapy: From cellular differentiation to mitochondrial transfer

Mesenchymal stem cells (MSCs) are characterized to have the capacity of self-renewal and the potential to differentiate into mesoderm, ectoderm-like and endoderm-like cells. MSCs hold great promise for cell therapies due to their multipotency in vitro and therapeutic advantage of hypo-immunogenicity and lower tumorigenicity. Moreover, it has been shown that MSCs can serve as a vehicle to transfer mitochondria into cells after cell transplantation. Mitochondria produce most of the energy through oxidative phosphorylation in differentiated cells. It has been increasingly clear that the switch of energy supply from glycolysis to aerobic metabolism is essential for successful differentiation of MSCs. Post-translational modifications of proteins have been established to regulate mitochondrial function and metabolic shift during MSCs differentiation. In this article, we review and provide an integrated view on the roles of different protein kinases and sirtuins in the maintenance and differentiation of MSCs. Importantly, we provide evidence to suggest that alteration in the expression of Sirt3 and Sirt5 and relative changes in the acylation levels of mitochondrial proteins might be involved in the activation of mitochondrial function and adipogenic differentiation of adipose-derived MSCs. We summarize their roles in the regulation of mitochondrial biogenesis and metabolism, oxidative responses and differentiation of MSCs. On the other hand, we discuss recent advances in the study of mitochondrial dynamics and mitochondrial transfer as well as their roles in the differentiation and therapeutic application of MSCs to improve cell function in vitro and in animal models. Accumulating evidence has substantiated that the therapeutic potential of MSCs is conferred not only by cell replacement and paracrine effects but also by transferring mitochondria into injured tissues or cells to modulate the cellular metabolism in situ. Therefore, elucidation of the underlying mechanisms in the regulation of mitochondrial metabolism of MSCs may ultimately improve therapeutic outcomes of stem cell therapy in the future.

The Succinate Receptor GPR91 Is Involved in Pressure Overload-Induced Ventricular Hypertrophy

Background

Pulmonary arterial hypertension is characterized by increased pressure overload that leads to right ventricular hypertrophy (RVH). GPR91 is a formerly orphan G-protein-coupled receptor (GPCR) that has been characterized as a receptor for succinate; however, its role in RVH remains unknown.

Methods and Results

We investigated the role of succinate-GPR91 signaling in a pulmonary arterial banding (PAB) model of RVH induced by pressure overload in SD rats. GPR91 was shown to be located in cardiomyocytes. In the sham and PAB rats, succinate treatment further aggravated RVH, up-regulated RVH-associated genes and increased p-Akt/t-Akt levels in vivo. In vitro, succinate treatment up-regulated the levels of the hypertrophic gene marker anp and p-Akt/t-Akt in cardiomyocytes. All these effects were inhibited by the PI3K antagonist wortmannin both in vivo and in vitro. Finally, we noted that the GPR91-PI3K/Akt axis was also up-regulated compared to that in human RVH.

Conclusions

Our findings indicate that succinate-GPR91 signaling may be involved in RVH via PI3K/Akt signaling in vivo and in vitro. Therefore, GPR91 may be a novel therapeutic target for treating pressure overload-induced RVH.

Changes in Caspase-3, B Cell Leukemia/Lymphoma-2, Interleukin-6, Tumor Necrosis Factor-α and Vascular Endothelial Growth Factor Gene Expression after Human Umbilical Cord Blood Derived Mesenchymal Stem Cells Transfusion in Pulmonary Hypertension Rat Models

Background and Objectives

Failure of vascular smooth muscle apoptosis and inflammatory response in pulmonary arterial hypertension (PAH) is a current research focus. The goals of this study were to determine changes in select gene expressions in monocrotaline (MCT)-induced PAH rat models after human umbilical cord blood derived mesenchymal stem cells (hUCB-MSCs) transfusion.

Materials and Methods

The rats were separated into 3 groups i.e., control group (C group), M group (MCT 60 mg/kg), and U group (hUCB-MSCs transfusion) a week after MCT injection.

Results

TUNEL assay showed that the U group had significantly lowered positive apoptotic cells in the lung tissues, as compared with the M group. mRNA of caspase-3, B cell leukemia/lymphoma (Bcl)-2, interleukin (IL)-6, tumor necrosis factor (TNF)-α and vascular endothelial growth factor (VEGF) in the lung tissues were greatly reduced at week 4 in the U group. Immunohistochemical staining of the lung tissues also demonstrated a similar pattern, with the exception of IL-6. The protein expression of caspase-3, Bcl-2 VEGF, IL-6, TNF-α and brain natriuretic peptide in the heart tissues were significantly lower in the U group, as compared with the M group at week 2. Furthermore, the protein expression of VEGF, IL-6 and BNP in the heart tissues were significantly lower in the U group at week 4. Collagen content in the heart tissues was significantly lower in the U group, as compared with M group at weeks 2 and 4, respectively.

Conclusion

hUCB-MSCs could prevent inflammation, apoptosis and remodeling in MCT-induced PAH rat models.

The Effect of Umbilical Cord Blood Derived Mesenchymal Stem Cells in Monocrotaline-induced Pulmonary Artery Hypertension Rats

Pulmonary arterial hypertension (PAH) causes right ventricular failure due to a gradual increase in pulmonary vascular resistance. The purposes of this study were to confirm the engraftment of human umbilical cord blood-mesenchymal stem cells (hUCB-MSCs) placed in the correct place in the lung and research on changes of hemodynamics, pulmonary pathology, immunomodulation and several gene expressions in monocrotaline (MCT)-induced PAH rat models after hUCB-MSCs transfusion. The rats were grouped as follows: the control (C) group; the M group (MCT 60 mg/kg); the U group (hUCB-MSCs transfusion). They received transfusions via the external jugular vein a week after MCT injection. The mean right ventricular pressure (RVP) was significantly reduced in the U group after the 2 week. The indicators of RV hypertrophy were significantly reduced in the U group at week 4. Reduced medial wall thickness in the pulmonary arteriole was noted in the U group at week 4. Reduced number of intra-acinar muscular pulmonary arteries was observed in the U group after 2 week. Protein expressions such as endothelin (ET)-1, endothelin receptor A (ERA), endothelial nitric oxide synthase (eNOS) and matrix metalloproteinase (MMP)-2 significantly decreased at week 4. The decreased levels of ERA, eNOS and MMP-2 immunoreactivity were noted by immnohistochemical staining. After hUCB-MSCs were administered, there were the improvement of RVH and mean RVP. Reductions in several protein expressions and immunomodulation were also detected. It is suggested that hUCB-MSCs may be a promising therapeutic option for PAH.

Microarray analysis after umbilical cord blood derived mesenchymal stem cells injection in monocrotaline-induced pulmonary artery hypertension rats

Pulmonary arterial hypertension (PAH) is associated with structural alterations of lung vasculature. PAH is still a devastating disease needing an aggressive therapeutic approach. Despite the therapeutic potential of human umbilical cord mesenchymal stem cells (MSCs), the molecular parameters to define the stemness remain largely unknown. Using high-density oligonucleotide microarrays, the differential gene expression profiles between a fraction of mononuclear cells of human umbilical cord blood (UCB) and its MSC subpopulation were obtained. Of particular interest was a subset of 46 genes preferentially expressed at 7-fold or higher in the group treated with human UCB-MSCs. This subset contained numerous genes involved in the inflammatory response, immune response, lipid metabolism, cell adhesion, cell migration, cell differentiation, apoptosis, cell growth, transport, cell proliferation, transcription, and signal transduction. Our results provide a foundation for a more reproducible and reliable quality control using genotypic analysis for the definition of human UCB-MSCs. Therefore, our results will provide a basis for studies on molecular mechanisms controlling the core properties of human MSCs.

Adipose-derived regenerative cell therapy inhibits the progression of monocrotaline-induced pulmonary hypertension in rats

AIMS

Functional and structural changes in pulmonary vasculature characterize pulmonary arterial hypertension (PAH) and the prognosis of advanced PAH remains poor despite progress in pharmacotherapy. Adipose-derived regenerative cells (ADRCs) promote cell regeneration at pathological sites and comprise a novel therapy for ailments of various organs. We investigated the effects of ADRC therapy in rat models of monocrotaline (MCT)-induced pulmonary hypertension (PH) and the underlying mechanisms.

MAIN METHODS

Rats were assigned to Control and MCT groups without and with (M/A) intravenous transfusion of seven million ADRCs on day 7. We echocardiographically evaluated pulmonary hypertension as pulmonary artery flow acceleration time (PAAT) and deceleration (PADc). Right ventricular (RV) systolic pressure was measured by catheterization on day 28 and then pathological changes in pulmonary vessels were assessed. We analyzed PAH-associated gene expression on day 14 using real-time RT-PCR.

KEY FINDINGS

Echocardiography and RV catheterization showed that ADRC therapy inhibited PH development (assessed as PAAT, PADc, and RV systolic pressure) at day 28 (MCT vs. M/A, P<0.05). Pulmonary vascular remodeling was also inhibited (vessel wall thickness: MCT vs. M/A, P<0.01). Messenger RNA levels of endothelin (ET) A and B receptors, ET-1 and transforming growth factor (TGF)-β increased in the lungs by MCT were suppressed by ADRCs (MCT vs. M/A, P<0.05).

SIGNIFICANCE

The development of PH was inhibited by ADRCs through suppressing changes in the expression of genes associated with ET and TGF-β systems. We believe that ADRC therapy could serve as a novel strategy for treating PH.

Mesenchymal stem cells: a promising therapy for the acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a pulmonary syndrome with growing prevalence and high mortality and morbidity that increase with age. There is no current therapy able to restore pulmonary function in ARDS patients. Preclinical models of ARDS have demonstrated that intratracheal or systemic administration of mesenchymal stem cells (MSCs) protects the lung against injury. The mechanisms responsible for the protective effects are multiple, including the secretion of multiple paracrine factors capable of modulating the immune response and restoring epithelial and endothelial integrity. Recent studies have demonstrated that MSCs can also control oxidative stress, transfer functional mitochondria to the damaged cells, and control bacterial infection by secretion of antibacterial peptides. These characteristics make MSCs promising candidates for ARDS therapy.