MicroRNA-9 modified bone marrow-derived mesenchymal stem cells (BMSCs) repair severe acute pancreatitis (SAP) via inducing angiogenesis in rats

Tumor Necrosis Factor Alpha Preconditioned Umbilical Cord Mesenchymal Stem Cell-Derived Extracellular Vesicles Enhance the Inhibition of Necroptosis of Acinar cells in Severe Acute Pancreatitis

Severe acute pancreatitis (SAP) is a common abdominal emergency with a high mortality rate and a lack of effective therapeutic options. Although mesenchymal stem cell (MSC) transplantation is a potential treatment for SAP, the mechanism remains unclear. It has been suggested that MSCs may act mainly through paracrine effects; therefore, we aimed to demonstrate the therapeutic efficacy of extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (UCMSCs) for SAP. Na-taurocholate was used to induce a rat SAP model through retrograde injection into the common biliopancreatic duct. After 72 h of EVs transplantation, pancreatic pathological damage was alleviated, along with a decrease in serum amylase activity and pro-inflammatory cytokine levels. Interestingly, when UCMSCs were preconditioned with 10 ng/mL tumor necrosis factor alpha (TNF-α) for 48 h, the obtained EVs (named TNF-α-EVs) performed an enhanced efficacy. Furthermore, both animal and cellular experiments showed that TNF-α-EVs alleviated the necroptosis of acinar cells of SAP through RIPK3/MLKL axis. In conclusion, our study demonstrated that TNF-α-EVs were able to enhance the therapeutic effect on SAP by inhibiting necroptosis compared to normal EVs. This study heralds that TNF-α-EVs may be a promising therapeutic approach for SAP in the future.

The Role of MicroRNAs in Pancreatitis Development and Progression

Pancreatitis (acute and chronic) is an inflammatory disease associated with significant morbidity, including a high rate of hospitalization and mortality. MicroRNAs (miRs) are essential post-transcriptional modulators of gene expression. They are crucial in many diseases' development and progression. Recent studies have demonstrated aberrant miRs expression patterns in pancreatic tissues obtained from patients experiencing acute and chronic pancreatitis compared to tissues from unaffected individuals. Increasing evidence showed that miRs regulate multiple aspects of pancreatic acinar biology, such as autophagy, mitophagy, and migration, impact local and systemic inflammation and, thus, are involved in the disease development and progression. Notably, multiple miRs act on pancreatic acinar cells and regulate the transduction of signals between pancreatic acinar cells, pancreatic stellate cells, and immune cells, and provide a complex interaction network between these cells. Importantly, recent studies from various animal models and patients' data combined with advanced detection techniques support their importance in diagnosing and treating pancreatitis. In this review, we plan to provide an up-to-date summary of the role of miRs in the development and progression of pancreatitis.

Bone Marrow Mesenchymal Stem Cells Modified with microRNA-216a-5p Enhance Proliferation of Acinar Cells in Severe Acute Pancreatitis

This study assesses the effect of bone marrow mesenchymal stem cells (BMSC) modified with miR-216a-5p on acinar cell proliferation in SAP. 40 rats were equally assigned into miR-NC set, miR-216a-5p set, BMSC set and anti-miR-216a-5p set randomly. The SAP model was prepared using AR42J cells which were disposed with CAE. Cells were transfected with lipidosome method to meaure miR-216-5p by RT-PCR, cell proliferation by CCK-8 along with analysis of cell clone formation and apoptosis. miR-216a-5p in modified BMSC was significantly upregulated compared with BMSC, indicating that BMSC was modified with miR-216a-5p successfully. BMSC modified with miR-216a-5p significantly promoted cell proliferation and clone formation and decreased apoptosis. The luciferase activity in wild type of miR-216a-5p was reduced, indicating that miR-216-5p could target Pak2 gene. In conclusion, proliferation of acinar cells in SAP is prompted and apoptosis ise reduced by BMSC modified with miR-216a-5p, which is possibly through targeting PAK2 gene.

Bone marrow-derived mesenchymal stem cells ameliorate severe acute pancreatitis by inhibiting oxidative stress in rats

To investigate whether bone marrow mesenchymal stem cells (BMSCs) attenuate pancreatic injury via mediating oxidative stress in severe acute pancreatitis (SAP). The SAP model was established in rats. Phosphate buffered saline (PBS) or BMSCs were injected into the rats by tail veins. ML385 was used to down-regulate Nrf2 expression in rats. Pancreatic pathological score was used to evaluated pancreatic injury. Inflammatory-associated cytokines, serum lipase and amylase, levels of myeloperoxidase, malondialdehyde, reactive oxygen species and superoxide dismutase, as well as catalase activity were measured for injury severity evaluation. ML385 aggravates oxidative stress in SAP + ML385 group, compared with SAP + PBS group. BMSCs transplantation alleviated pancreatic injury and enhance antioxidant tolerance in SAP + BMSCs group, while ML385 administration weakened this efficacy in SAP + BMSCs + ML385 group. In addition, BMSCs promoted Nrf2 nuclear translocation via PI3K/AKT signaling pathway. Besides, BMSCs reduced inflammatory response by inhibiting NF-κB signaling pathway in SAP. BMSCs can inhibit oxidative stress and reduce pancreatic injury via inducing Nrf2 nuclear translocation in SAP.

New challenges for microRNAs in acute pancreatitis: progress and treatment

Acute pancreatitis (AP) is a common clinical abdominal emergency, with a high and increasing incidence each year. Severe AP can easily cause systemic inflammatory response syndrome, multiple organ dysfunction and other complications, leading to higher hospitalization rates and mortality. Currently, there is no specific treatment for AP. Thus, we still need to understand the exact AP pathogenesis to effectively cure AP. With the rise of transcriptomics, RNA molecules, such as microRNAs (miRNAs) transcribed from nonprotein-coding regions of biological genomes, have been found to be of great significance in the regulation of gene expression and to be involved in the occurrence and development of many diseases. Increasing evidence has shown that miRNAs, as regulatory RNAs, can regulate pancreatic acinar necrosis and apoptosis and local and systemic inflammation and play an important role in the development and thus potentially the diagnosis and treatment of AP. Therefore, here, the current research on the relationship between miRNAs and AP is reviewed.

Bone Marrow Mesenchymal Stem Cells (BMSCs) Transplantation Alleviates Acute Pancreatitis Through Inhibiting Inflammation and Promoting Caspase-8 Apoptosis Pathway

Bone marrow mesenchymal stem cells (BMSCs) are capable of multipolar differentiation and repairing injured tissues. Herein, we aimed to investigate the mechanism by how BMSCs modulate the apoptotic pathway in the acute pancreatitis (AP). In this study, primary BMSCs were cultured and administrated into 10 AP mice while 10 healthy mice were taken as a blank group and 10 AP mice as a control group. The mouse pancreatic tissues were assessed by HE staining and evaluated by pancreatitis score and serum amylase detection. Level of inflammatory factors CRP and TNF-α was measured by ELISA and PIPK1, PIPK3, MLKL and Caspase-8 expression was detected by RT-qPCR and Western blot. The pancreatitis score (7.29±1.36) and the serum amylase score of (453.66±103.67) mu/ml of BMSCs group was significantly higher than that of control group, indicating increased tissue repair after BMSCs treatment. BMSCs group exhibited a higher level of CRP (711.01±115.31) and TNF-α (132.81±22.13) in serum compared to control group (p < 0.05). PIPK1, PIPK3, and MLKL expression in BMSCs group decreased (p < 0.05) whereas Caspase-8 was increased (p < 0.05). On the other hand, BMSCs group presented upregulated PIPK1, PIPK3, and MLKL (p < 0.05) and downregulated Caspase-8 (p < 0.05). In conclusion, BMSCs regulate cell apoptosis by upregulating Caspase-8 expression, and downregulating PIPK1, PIPK3 and MLKL level, thereby alleviating the inflammation in AP.

Müller glia-derived exosomal miR-9-3p promotes angiogenesis by restricting sphingosine-1-phosphate receptor S1P1 in diabetic retinopathy

Diabetic retinopathy is a heterogeneous retinal degenerative disease with the microvascular dysfunction being recognized as a hallmark of the advanced stage. In this study, we demonstrated that exosomes collected from the vitreous humor of proliferative diabetic retinopathy patients promoted proliferation, migration and tube formation ability of primary human retinal endothelial cells via its elevated miR-9-3p expression level. Müller glia cells were further recognized as the sole source of the aberrantly expressed miR-9-3p, and both in vitro and in vivo experiments validated that Müller glia-derived exosomes aggravate vascular dysfunction under high glucose. Mechanistically, exosomal miRNA-9-3p was transferred to retinal endothelial cells and bound to the sphingosine-1-phosphate receptor S1P₁ coding sequence, which subsequently activated VEGFR2 phosphorylation and internalization in the presence or absence of exogenous VEGF-A. We successfully orchestrated the dynamic crosstalk between retinal Müller glia cells and endothelial cells in pathological condition, which may provide a novel biomarker or promising therapeutic agents for the treatment of diabetic retinopathy.

Diabetic Bone Marrow Cell Injection Accelerated Acute Pancreatitis Progression

Acute pancreatitis (AP) is one of the leading causes of hospital admission, 20% of which could progress to the severe type with extensive acinar cell necrosis. Clinical studies have reported that diabetes is an independent risk factor of the incidence of AP and is associated with higher severity than nondiabetic subjects. However, how diabetes participates in AP progression is not well defined. To investigate this question, wild-type (wt) and diabetic db/db mice at the age of 16 weeks were used in the study. AP was induced in wt recipients by 10 injections of 50 μg/kg caerulein with a 1 h interval. One hour after the last caerulein injection, bone marrow cells (BMC) isolated from wt and db/db mice were injected intraperitoneally into the recipients (1 × 10⁷cells/recipient). The recipients with no BMC injection served as controls. Thirteen hours after BMC injection, serum lipase activity was 1.8- and 1.3-folds higher in mice that received db/db BMC, compared with those with no injection and wt BMC injection, respectively (p ≤ 0.02 for both). By H&E staining, the overall severity score was 14.7 for no cell injection and 16.6 for wt BMC injection and increased to 22.6 for db/db BMC injection (p ≤ 0.002 for both). In particular, mice with db/db BMC injection developed more acinar cell necrosis and vacuolization than the other groups (p ≤ 0.03 for both). When sections were stained with an antibody against myeloperoxidase (MPO), the density of MPO+ cells in pancreatitis was 1.9- and 1.6-folds higher than wt BMC and no BMC injection groups, separately (p ≤ 0.02 for both). Quantified by ELISA, db/db BMC produced more IL-6, GM-CSF, and IL-10 compared with wt BMC (p ≤ 0.04 for all). In conclusion, BMC of db/db mice produced more inflammatory cytokines. In response to acinar cell injury, diabetic BMC aggravated the inflammation cascade and acinar cell injury, leading to the progression of acute pancreatitis.

MiR-20b-5p modulates inflammation, apoptosis and angiogenesis in severe acute pancreatitis through autophagy by targeting AKT3

BACKGROUND

Severe acute pancreatitis (SAP) is a common acute abdominal disease with high morbidity and mortality. However, the mechanism underlying SAP is still unclear.

METHODS

Cerulean and LPS (Cer-LPS) was used to establish a rat model and an in vitro model of SAP. qRT-PCR, western blot and IHC were determined to analyse the expression of mRNA and proteins. IL-1β, TNF-α and IL-6 levels were measured applying ELISA. H&E staining was determined to observe the pathological changes. Apoptosis was tested by AV-PI staining using flow cytometry. CCK8 assay was taken to detect cell viability. Cell migration was assessed by transwell assay. Tube formation assay was conducted to evaluate angiogenesis. Luciferase assay was used to detect relationship of miR-20b-5p and AKT3.

RESULTS

MiR-20b-5p was lowly expressed in SAP models both in vivo and in vitro. Overexpression of miR-20b-5p restrained inflammation and apoptosis in Cer-LPS treated pancreatic acinar cells. Furthermore, miR-20b-5p promoted the angiogenesis of vascular endothelial cells, since the viability, migration and the capability of tube formation were increased by miR-20b-5p. Mechanically, miR-20b-5p directly targeted AKT3 to promote autophagy. Furthermore, miR-20b-5p could prevent the inflammation, apoptosis and enhance angiogenesis via enhancing autophagy, which was verified in vivo.

CONCLUSION

This study demonstrated miR-20b-5p attenuates SAP through directly targeting AKT3 to regulate autophagy, subsequently inhibit inflammation and apoptosis, and promote angiogenesis. Our findings suggested a novel target of miR-20b-5p for the therapy of SAP.

miR-9 alleviated the inflammatory response and apoptosis in caerulein-induced acute pancreatitis by regulating FGF10 and the NF-κB signaling pathway

MicroRNAs (miRs) have been implicated in the development of acute pancreatitis (AP). However, the role and potential mechanism of miR-9 in AP progression remains unclear. Caerulein-treated AR42J cells were used as a cellular model of AP. Results revealed caerulein triggered an inflammatory response by promoting the secretion of inflammatory cytokines [tumor necrosis factor-α, interleukin (IL) 1β and IL-6], as evidenced by ELISA. Furthermore, caerulein-induced apoptosis was reported by flow cytometry and western blot assays. Additionally, miR-9 expression was downregulated by caerulein treatment, as demonstrated by reverse transcription quantitative PCR. However, miR-9 overexpression reduced the inflammatory response and apoptosis in caerulein-treated AR42J cells. miR-9 knockdown resulted in opposite effects. Furthermore, fibroblast growth factor (FGF) 10 was validated to be targeted via miR-9 by luciferase, RNA immunoprecipitation and RNA pull-down assays. Results demonstrated increased FGF10 expression in caerulein-treated AR42J cells and that FGF10 overexpression exacerbated the caerulein-induced inflammatory response and apoptosis, while its knockdown had the opposite effect. Additionally, FGF10 reversed the effect of miR-9 on caerulein-induced injury in AR42J cells. Results demonstrated that miR-9 inhibited the expression of the nuclear factor κB (NF-κB) pathway-related proteins by downregulating FGF10. As a result, miR-9 decreased inflammatory response and apoptosis in caerulein-treated AR42J cells by targeting FGF10 and blocking NF-κB signaling, suggesting that miR-9 may serve as a novel target for AP treatment.

Mesenchymal stromal cell therapy for pancreatitis: Progress and challenges

Pancreatitis is a common gastrointestinal disease with no effective therapeutic options, particularly for cases of severe acute and chronic pancreatitis (CP). Mesenchymal stromal cells (MSCs) are multipotent cells with diverse biological properties, including directional migration, paracrine, immunosuppressive, and antiinflammatory effects, which are considered an ideal candidate cell type for repairing tissue damage caused by various pathogenies. Several researchers have reported significant therapeutic efficacy of MSCs in animal models of acute and CP. However, the specific underlying mechanisms are yet to be clarified and clinical application of MSCs as pancreatitis therapy has rarely been reported. This review mainly focuses on the potential and challenges in clinical application of MSCs for treatment of acute and CP, along with discussion of the underlying molecular mechanisms.

From hair to pancreas: transplanted hair follicle mesenchymal stem cells express pancreatic progenitor cell markers in a rat model of acute pancreatitis

Acute pancreatitis (AP) is commonly accompanied by intense pain and is associated with high mortality rates. However, the effectiveness of existing therapeutic approaches remains unsatisfactory. Stem cell therapy, which can promote the regeneration of damaged tissue and alleviate systemic inflammatory responses, has brought new possibility for patients suffering from AP. In particular, hair follicle-derived mesenchymal stem cells (HF-MSCs) are proposed as a suitable cell source for treating pancreatic diseases, but further research on their effectiveness, safety, and underlying mechanisms is warranted for clinical implementation. In this work, the therapeutic potential of HF-MSC transplantation was studied in an L-arginine-induced AP rat model. HF-MSCs were extracted from infant Sprague-Dawley (SD) rats, expanded in vitro, and detected by flow cytometry. HF-MSCs were labeled by PKH67 and transplanted into rats with AP via tail vein injection. Serum specimens were collected at 24 h, 48 h, and 72 h after transplantation, and the levels of amylase, lipase, and anti-inflammatory factors, namely interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), were analyzed. Pancreas samples were collected and assayed by immunofluorescence and immunohistochemistry 1 week after transplantation to monitor the differentiation of HF-MSCs and the functional recovery of the damaged pancreas. Intravenously delivered rat HF-MSCs spontaneously homed to the damaged pancreas and expressed pancreatic progenitor cell markers, relieved inflammation, and boosted pancreatic regeneration. These findings indicate that HF-MSC transplantation is a potentially effective treatment for AP.

Resveratrol supplementation and acute pancreatitis: A comprehensive review

Resveratrol, a natural polyphenolic ingredient extracted from herbs, suppresses oxidative stress and inflammation. We performed a comprehensive review to find any evidence about the effects of Resveratrol on acute pancreatitis (AP). Resveratrol has been found to directly impact cytokine generation. As these factors play a crucial role in the pathophysiology of AP, resveratrol might attenuate AP and its complications. Mechanistically, resveratrol exerts its pharmacological effects through anti-inflammatory and antioxidant mechanisms via interaction with different signaling molecules and transcription factors. Indeed, resveratrol might prove to be an effective therapeutic component for AP treatment in the future. In this review, we shed light on potential most recent pathways through which resveratrol might impact the management and control of AP.

Long noncoding RNA H19 regulates the therapeutic efficacy of mesenchymal stem cells in rats with severe acute pancreatitis by sponging miR-138-5p and miR-141-3p

Background

Patients with severe acute pancreatitis (SAP), which is characterized by high morbidity and mortality, account for an increasing medical burden worldwide. We previously found that mesenchymal stem cells (MSCs) could attenuate SAP and that expression of long noncoding RNA H19 (LncRNA H19) was upregulated in rats receiving MSCs. In the present study, we investigated the mechanisms of LncRNA H19 regulating the therapeutic efficacy of MSCs in the alleviation of SAP.

Methods

MSCs transfected with LncRNA H19 overexpression and knockdown plasmids were intravenously injected into rats 12 h after sodium taurocholate (NaT) administration to induce SAP.

Results

Overexpressing LncRNA H19 in MSCs significantly enhanced the anti-inflammatory capacity of the MSCs, inhibited autophagy via promotion of focal adhesion kinase (FAK)-associated pathways, and facilitated cell proliferation by increasing the level of β-catenin in rats with SAP. LncRNA H19 functioned as a competing endogenous RNA by sponging miR-138-5p and miR-141-3p. Knocking down miR-138-5p in MSCs increased the expression of protein tyrosine kinase 2 (PTK2, encoding FAK) to suppress autophagy, while downregulating miR-141-3p enhanced the level of β-catenin to promote cell proliferation.

Conclusions

In conclusion, LncRNA H19 effectively increased the therapeutic efficacy of MSCs in rats with SAP via the miR-138-5p/PTK2/FAK and miR-141-3p/β-catenin pathways.

MiR-9 Promotes Angiogenesis via Targeting on Sphingosine-1- Phosphate Receptor 1

We previously demonstrated that vascular endothelial cells released VEGF-enriched exosomes to promote the tumor vasculogenesis and progression after anti-angiogenic therapies (AATs). To clarify how microRNA (miR)-9 promoted the angiogenesis of tumor-associated endothelial cells, in the present study, we investigated the association between miR-9 and sphingosine-1-phosphate (S1P) receptors in angiogenesis. The levels of miR-9 and S1P receptors in normal and tumor endothelial cells were compared with EndoDB database and their correlations were analyzed. The levels of S1P₁, S1P₂, and S1P₃ were detected in miR-9 overexpressing endothelial cells by qRT-PCR and western blot. The binding sites of miR-9 on S1P₁ and S1P₃ were predicted and tested by dual-luciferase reporter assays. Then, angiogenesis in endothelial cells overexpressing both S1P₁ and miR-9 was detected. The results showed that miR-9 is overexpressed in ECs from medulloblastoma and glioblastoma xenograft, which is negatively associated with S1P₁ and S1P₃. Overexpression of miR-9 significantly inhibited S1P₁ and S1P₃ in both mRNA and protein levels. We predicted that binding sites exist between miR-9 and S1P₁, S1P₃, but only S1P₁ was directly targeted by miR-9. Overexpression of S1P₁ significantly suppressed the miR-9-induced angiogenesis. Therefore, miR-9 induces angiogenesis via targeting on S1P₁.

Bone Marrow Mesenchymal Stem Cell-Derived Exosomes Attenuate LPS-Induced ARDS by Modulating Macrophage Polarization Through Inhibiting Glycolysis in Macrophages

Macrophages play a key role in the development of sepsis-induced acute respiratory distress syndrome (ARDS). Recent evidence has proved that glycolysis plays an important role in regulating macrophage polarization through metabolic reprogramming. Bone marrow mesenchymal stem cells (BMSCs) can alleviate sepsis-induced lung injury and possess potent immunomodulatory and immunosuppressive properties via secreting exosomes. However, it is unknown whether BMSCs-derived exosomes exert their therapeutic effect against sepsis-induced lung injury by inhibiting glycolysis in macrophages. Therefore, the present study aimed to evaluate the anti-inflammatory effects of exosomes released from BMSCs on acute lung injury induced by lipopolysaccharide (LPS) in mice and explored the possible underlying mechanisms in vitro and in vivo. We found that BMSCs inhibited M1 polarization and promoted M2 polarization in MH-S cells (a murine alveolar macrophage cell line) by releasing exosomes. Further experiments showed that exosomes secreted by BMSCs modulated LPS-treated MH-S cells polarization by inhibiting cellular glycolysis. Moreover, our results showed that BMSCs-derived exosomes down-regulated the expression of several essential proteins of glycolysis via inhibition of hypoxia-inducible factor 1 (HIF-1)α. Finally, a model of LPS-induced ARDS in mice was established, we found that BMSCs-derived exosomes ameliorated the LPS-induced inflammation and lung pathological damage. Meanwhile, we found that intratracheal delivery of BMSCs-derived exosomes effectively down-regulated LPS-induced glycolysis in mice lung tissue. These findings reveal new mechanisms of BMSCs-derived exosomes in regulating macrophage polarization which may provide novel strategies for the prevention and treatment of LPS-induced ARDS.

Nonsteroidal anti-inflammatory drugs alleviate severity of post-endoscopic retrograde cholangiopancreatography pancreatitis by inhibiting inflammation and reducing apoptosis

BACKGROUND AND AIM

The prophylactic effect of nonselective nonsteroidal anti-inflammatory drugs on post-ERCP (endoscopic retrograde cholangiopancreatography) pancreatitis has been observed for a long time. However, whether the selective nonsteroidal anti-inflammatory drugs possess similar abilities and the mechanisms by which nonsteroidal anti-inflammatory drugs work remain unclear. The present study aimed to determine the protective effects of nonsteroidal anti-inflammatory drugs on post-ERCP pancreatitis in a rat model and examine underlying mechanisms.

METHODS

Thirty-two female rats were equally and randomly divided into four groups: the sham group, post-ERCP pancreatitis model group, indomethacin-pretreated group, and parecoxib-pretreated group. Indomethacin or parecoxib was delivered 30 min prior to surgery; 24 h after post-ERCP pancreatitis establishment, the rats were sacrificed. Serum amylase and lipase activities, inflammatory cytokine release, pancreatic histopathological scores, neutrophil infiltration, and the expression pattern cyclooxygenase at the protein level and pancreatic apoptosis were quantified and analyzed.

RESULTS

Both indomethacin and parecoxib inhibited the activities of serum amylase and lipase and reduced the severity of pancreatic histopathology. Mechanistically, both drugs decreased the expression level of cyclooxygenase 2; however, they had no influence on the cyclooxygenase 1 protein level. Moreover, they reduced inflammatory cytokine release, neutrophil infiltration into the pancreas, and NF-κB p65 activation. Notably, we found that apoptotic cells in the pancreas were remarkably diminished after the administration of both nonsteroidal anti-inflammatory drugs.

CONCLUSIONS

Both selective and nonselective nonsteroidal anti-inflammatory drugs exert protective effects against post-ERCP pancreatitis by restraining inflammation and reducing acinar cell apoptosis through the inhibition of cyclooxygenase 2.

MiR-9 promotes angiogenesis of endothelial progenitor cell to facilitate thrombi recanalization via targeting TRPM7 through PI3K/Akt/autophagy pathway

Endothelial progenitor cells (EPCs) have emerged as a promising therapeutic choice for thrombi recanalization. However, this role of EPCs is confined by some detrimental factors. The aim of this study was to explore the role of the miR‐9‐5p in regulation of the proliferation, migration and angiogenesis of EPCs and the subsequent therapeutic role in thrombosis event. Wound healing, transwell assay, tube formation assay and in vivo angiogenesis assay were carried out to measure cell migration, invasion and angiogenic abilities, respectively. Western blot was performed to elucidate the relationship between miR‐9‐5p and TRPM7 in the autophagy pathway. It was found that miR‐9‐5p could promote migration, invasion and angiogenesis of EPCs by attenuating TRPM7 expression via activating PI3K/Akt/autophagy pathway. In conclusion, miR‐9‐5p, targets TRPM7 via the PI3K/Ak/autophagy pathway, thereby mediating cell proliferation, migration and angiogenesis in EPCs. Acting as a potential therapeutic target, miR‐9‐5p may play an important role in the prognosis of DVT.

Resveratrol improves the therapeutic efficacy of bone marrow-derived mesenchymal stem cells in rats with severe acute pancreatitis

OBJECTIVE

Bone marrow-derived mesenchymal stem cells (BMSCs) are effective in the treatment of severe acute pancreatitis (SAP), but their therapeutic effects could still be improved. In order to optimize the clinical application of BMSCs, we adopted the strategy of resveratrol (Res) pretreatment of BMSCs (Res-BMSCs) and applied it to a rat model of sodium taurocholate (NaT)-induced acute pancreatitis.

METHODS

SAP was induced by injection of 3% NaT into the pancreatic duct and successful induction of SAP occurred after 12 h. Rats were treated with BMSCs, Res or BMSCs primed with Res at 40 mmol/L, Vandetanib (ZD6474) daily oral dosages of 50 mg/kg vandetanib.

RESULTS

Res stimulated BMSCs to secrete vascular endothelial growth factor A (VEGFA), activated the downstream phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway, and inhibited pancreatic cell apoptosis. In addition, conditioned medium (CM) from Res-BMSCs enhanced the proliferation of human umbilical vein endothelial cells (HUVECs) in vitro, increased resistance to apoptosis and promoted the expression of angiogenesis-related proteins CD31, VEGF and VEGFR2 in pancreatic tissue, but Vandetanib partly abolished these effects by blocking the VEGFA- mediated pathway.

CONCLUSION

Resveratrol-preprocessed BMSCs can activate the PI3K/AKT signaling pathway in pancreatic cells and HUVECs through paracrine release of VEGFA; thus, achieving the therapeutic effect of resisting apoptosis of pancreatic cells and promoting regeneration of damaged blood vessels. Res pretreatment may be a new strategy to improve the therapeutic effect of BMSCs on SAP.

Bone marrow-derived mesenchymal stem cells alleviate severe acute pancreatitis-induced multiple-organ injury in rats via suppression of autophagy

Patients with severe acute pancreatitis (SAP) represent a substantial challenge to medical practitioners due to the high associated rates of morbidity and mortality and a lack of satisfactory therapeutic outcomes. In a previous study, our group demonstrated that bone marrow-derived mesenchymal stem cells (BMSCs) can ameliorate SAP; however, the mechanisms of action remain to be fully understood. BMSCs were intravenously injected into SAP rats 12 h after experimental induction of SAP using sodium taurocholate (NaT). Histopathological changes and the levels of pro-inflammatory mediators were assessed by hematoxylin and eosin (H&E) staining and ELISA, respectively. Autophagy levels were assessed using qRT-PCR, western blotting, immunohistochemistry, immunofluorescence, and transmission electron microscopy. AR42J cells and human umbilical vein endothelial cells (HUVECs) were administered BMSC-conditioned media (BMSC-CM) after NaT treatment, and cell viability was measured using a Cell Counting Kit-8 (CCK-8) and flow cytometry. In vivo, BMSCs effectively reduced multiple systematic inflammatory responses, suppressed the activation of autophagy, and improved intestinal dysfunction. In vitro, BMSC-CM significantly improved the viability of injured cells, promoted angiogenesis, and decreased autophagy. We therefore propose that the administration of BMSCs alleviates SAP-induced multiple organ injury by inhibiting autophagy.

MicroRNAs in acute pancreatitis: From pathogenesis to novel diagnosis and therapy

Acute pancreatitis (AP) is an inflammatory disorder initiated by activation of pancreatic zymogens, leading to pancreatic injury and systemic inflammatory response. MicroRNAs (miRNAs) have emerged as important regulators of gene expression and key players in human physiological and pathological processes. Discoveries over the past decade have confirmed that altered expression of miRNAs is implicated in the pathogenesis of AP. Indeed, a number of miRNAs have been found to be dysregulated in various cell types involved in AP such as acinar cells, macrophages, and lymphocytes. These aberrant miRNAs can regulate acinar cell necrosis and apoptosis, local and systemic inflammatory response, thereby contributing to the initiation and progression of AP. Moreover, patients with AP possess unique miRNA signatures when compared with healthy individuals or those with other diseases. In view of their stability and easy detection, therefore, miRNAs have the potential to act as biomarkers for the diagnosis and assessment of patients with AP. In this review, we provide an overview of the novel cellular and molecular mechanisms underlying the roles of miRNAs during the disease processes of AP, as well as the potential diagnosis and therapeutic biomarkers of miRNAs in patients with AP.

Mesenchymal stem cells decrease blood-brain barrier permeability in rats with severe acute pancreatitis

Background

Impairment of the blood–brain barrier (BBB) could result in secondary cerebral edema and life-threatening pancreatic encephalopathy in patients with severe acute pancreatitis (SAP). Mesenchymal stem cells (MSCs) have been widely adopted in clinical research because of their pleiotropic functions. The aim of this study was to investigate the impact of MSCs on BBB permeability in SAP and the potential mechanisms driving these effects.

Methods

Sprague-Dawley rats were randomly assigned to the control, SAP and SAP+MSCs groups. Pancreatic impairment was assessed. The serum levels of amylase, TNF-α and IL-10, expression levels of claudin-5, Bax, Bcl-2 and MMP-9, and the BBB permeability were measured. Endothelial cell apoptosis was evaluated.

Results

SAP rats showed BBB impairment with increased permeability and secondary cerebral edema, which was confirmed using the Evans blue assay and the calculation of the brain dry/wet ratio. Treatment with MSCs decreased the serum levels of amylase and TNF-α, increased the serum levels of IL-10, attenuated the apoptosis of brain microvascular endothelial cells, upregulated claudin-5 expression and downregulated MMP-9 expression. This treatment attenuated the increased BBB permeability in SAP rats.

Conclusions

MSCs attenuated the impairment of the BBB and decreased its permeability, producing protective effects in SAP rats.

Electronic supplementary material

The online version of this article (10.1186/s11658-019-0167-8) contains supplementary material, which is available to authorized users.