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

Periplocin targets LRP4 to regulate metabolic homeostasis and anti-inflammation for the treatment of IVDD

BACKGROUND

Intervertebral disc degeneration (IVDD) is characterized by deteriorating intervertebral discs, leading primarily to low back pain and leg pain. Most current treatments for IVDD primarily address symptoms without targeting the underlying degenerative process. Moreover, tumor necrosis factor-α (TNF-α)-mediated inflammation and degradation of the nucleus pulposus (NP) extracellular matrix (ECM) influence this pathological process. Periplocin, a cardiotonic steroid extracted from periplocin forrestii, has demonstrated a wide range of medical benefits, including cardiotonic, anticancer, anti-inflammatory, and wound healing properties. Nevertheless, the effects of periplocin on IVDD remain unexplored.

OBJECTIVE

Our study explores the mechanism of action and the potential target of periplocin in mitigating IVDD pathology.

METHODS

Rat models of IVDD were established using acupuncture, and the affected discs underwent analysis via Safranin O-Fast Green (S-O) and Hematoxylin and Eosin (H&E) staining. Nucleus pulposus cells (NPCs) were harvested from IVDD patients and experimental animals for examination. A variety of techniques, including Western blot analysis, quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) assay, immunofluorescence staining, Alcian Blue staining and Immunohistochemistry (IHC) staining, were utilized to evaluate inflammation-related proteins, mRNAs and the ECM metabolism. In order to ascertain the potential protein targets of periplocin, the binding site of periplocin to LRP4 was elucidated through the utilisation of molecular docking experiments. Subsequently, the expression of low-density lipoprotein receptor-related protein 4 (LRP4) in NPCs was modified through the use of small interfering RNA (siRNA) knockdown and overexpression vectors, which were employed for the purposes of target validation.

RESULTS

We conclude from the present study that periplocin alleviates the progression of IVDD mainly through the following aspects: periplocin inhibits TNF-α-induced inflammatory; periplocin reduces matrix degradation; periplocin promotes matrix anabolism and regulates metabolic homeostasis. Moreover, the present study demonstrates that LRP4 is involved as a potential target in the multiple pathways mentioned above to protect the intervertebral disc.

CONCLUSION

Our research suggests that periplocin may serve as a promising treatment for IVDD, offering anti-inflammatory benefits, preventing ECM degradation, and promoting ECM anabolism.

The glycocalyx: a key target for treatment of severe acute pancreatitis-associated multiple organ dysfunction syndrome

The endothelial glycocalyx is a dynamic brush-like layer composed of proteoglycans and glycosaminoglycans, including heparan sulfate (HS) and hyaluronic acid (HA), and is an important regulator of vascular homeostasis. Its structure (thickness ranges from 20 to 6450 nm in different species) not only provides a charge-selective barrier but also serves to anchor mechanosensors such as the glypican-1 (GPC-1)/caveolin-1 (CAV-1) complex and buffers shear stress. In severe acute pancreatitis (SAP), inflammatory factors promote the expression of matrix metalloproteinases (MMPs) and heparinases, which degrade syndecan-1 (SDC-1) and HS, while oxidative stress disrupts HA-CD44 binding, leading to increased capillary leakage and neutrophil adhesion. This degradation process occurs before the onset of multiple organ dysfunction syndrome (MODS), highlighting the potential of the glycocalyx as an early biomarker. More importantly, the regeneration of glycocalyx through endothelial cell synthesis of glycosaminoglycans (GAGs) and shear stress-driven SDC recycling provides therapeutic prospects. This review redefines the pathophysiology of severe acute pancreatitis-associated multiple organ dysfunction (SAP-MODS) by exploring the glycocalyx's central mechanistic role and proposes stabilizing glycocalyx structure as a potential strategy to prevent microcirculatory failure.

Pro-inflammatory cytokines stimulate CFTR-dependent anion secretion in pancreatic ductal epithelium

BACKGROUND

Loss of CFTR-dependent anion and fluid secretion in the ducts of the exocrine pancreas is thought to contribute to the development of pancreatitis, but little is known about the impact of inflammation on ductal CFTR function. Here we used adult stem cell-derived cell cultures (organoids) obtained from porcine pancreas to evaluate the effects of pro-inflammatory cytokines on CFTR function.

METHODS

Organoids were cultured from porcine pancreas and used to prepare ductal epithelial monolayers. Monolayers were characterized by immunocytochemistry. Epithelial bicarbonate and chloride secretion, and the effect of IL-1β, IL-6, IFN-γ, and TNF-α on CFTR function was assessed by electrophysiology.

RESULTS

Immunolocalization of ductal markers, including CFTR, keratin 7, and zonula occludens 1, demonstrated that organoid-derived cells formed a highly polarized epithelium. Stimulation by secretin or VIP triggered CFTR-dependent anion secretion across epithelial monolayers, whereas purinergic receptor stimulation by UTP, elicited CFTR-independent anion secretion. Most of the anion secretory response was attributable to bicarbonate transport. The combination of IL-1β, IL-6, IFN-γ, and TNF-α markedly enhanced CFTR expression and anion secretion across ductal epithelial monolayers, whereas these cytokines had little effect when tested separately. Although TNF-α triggered apoptotic signaling, epithelial barrier function was not significantly affected by cytokine exposure.

CONCLUSIONS

Pro-inflammatory cytokines enhance CFTR-dependent anion secretion across pancreatic ductal epithelium. We propose that up-regulation of CFTR in the early stages of the inflammatory response, may serve to promote the removal of pathogenic stimuli from the ductal tree, and limit tissue injury.

Incidence and outcomes of pancreatic encephalopathy in patients with acute pancreatitis: a systematic review and meta-analysis

Pancreatic encephalopathy (PE) is a lethal complication of acute pancreatitis (AP), but its clinical characteristics and prognosis remain obscure. Herein, we performed a systematic review and meta-analysis to evaluate the incidence and outcomes of PE in AP patients. PubMed, EMBASE, and China National Knowledge Infrastructure were searched. Based on the data from cohort studies, the incidence and mortality of PE in AP patients were pooled. Based on the individual data from case reports, logistic regression analyses were performed to identify the risk factors for death in PE patients. Among 6702 papers initially identified, 148 were included. Based on 68 cohort studies, the pooled incidence and mortality of PE in AP patients were 11% and 43%, respectively. The causes of death were clearly reported in 282 patients, of which the most common was multiple organ failure (n = 197). Based on 80 case reports, 114 AP patients with PE were included. The causes of death were clearly reported in 19 patients, of which the most common was multiple organ failure (n = 8). Univariate analyses showed that multiple organ failure (OR = 5.946; p = 0.009) and chronic cholecystitis (OR = 5.400; p = 0.008) were the significant risk factors of death among patients with PE. PE is not a rare complication of AP and indicates poor prognosis. Such a high mortality of PE patients may be attributed to its coexistence of multiple organ failure.

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.

[Prediction and diagnosis of pancreatogenic encephalopathy in patients with destructive pancreatitis]

OBJECTIVE

To study the literature data on pancreatogenic encephalopathy in patients with destructive pancreatitis.

MATERIAL AND METHODS

Searching for Russian- and English-language literature data was carried out in electronic databases: elibrary, PubMed, the Cochrane Library. We planned a systematic review if studies with evidence level 1 and 2 were available. If these trials were absent, descriptive review was considered.

RESULTS

No studies with evidence level 1 and 2 were found in available literature. Therefore, a descriptive review was carried out. Analysis of primary sources showed that the incidence of pancreatogenic encephalopathy is 9-35% and has no direct correlation with etiology of destructive pancreatitis. Major factors of pathogenesis are high serum enzymes, activation of proinflammatory cytokines and hypoxemia, which are accompanied by damage to myelin sheath of the white matter and cytotoxic brain edema. Clinical manifestation of pancreatogenic encephalopathy occurs within two weeks. Acute onset and various symptoms are typical. Possible laboratory predictors of encephalopathy are persistent hyperglycemia, increased hematocrit, fibrinogen-like protein 2 (FPB-2), proinflammatory cytokines TNF-αand interleukin-1-beta. Pancreatogenic encephalopathy is a factor of unfavorable prognosis of treatment. Mortality in patients with pancreatogenic encephalopathy is 57-70%. Favorable course of pancreatic necrosis is followed by regression of cerebral disorders in most cases while residual cognitive disorders are possible in elderly patients.

CONCLUSION

Pancreatogenic encephalopathy accompanies severe destructive pancreatitis. It is an unfavorable factor for treatment outcomes requiring further research.

Treating Metastatic Brain Cancers With Stem Cells

Stem cell therapy may present an effective treatment for metastatic brain cancer and glioblastoma. Here we posit the critical role of a leaky blood-brain barrier (BBB) as a key element for the development of brain metastases, specifically melanoma. By reviewing the immunological and inflammatory responses associated with BBB damage secondary to tumoral activity, we identify the involvement of this pathological process in the growth and formation of metastatic brain cancers. Likewise, we evaluate the hypothesis of regenerating impaired endothelial cells of the BBB and alleviating the damaged neurovascular unit to attenuate brain metastasis, using the endothelial progenitor cell (EPC) phenotype of bone marrow-derived mesenchymal stem cells. Specifically, there is a need to evaluate the efficacy for stem cell therapy to repair disruptions in the BBB and reduce inflammation in the brain, thereby causing attenuation of metastatic brain cancers. To establish the viability of stem cell therapy for the prevention and treatment of metastatic brain tumors, it is crucial to demonstrate BBB repair through augmentation of vasculogenesis and angiogenesis. BBB disruption is strongly linked to metastatic melanoma, worsens neuroinflammation during metastasis, and negatively influences the prognosis of metastatic brain cancer. Using stem cell therapy to interrupt inflammation secondary to this leaky BBB represents a paradigm-shifting approach for brain cancer treatment. In this review article, we critically assess the advantages and disadvantages of using stem cell therapy for brain metastases and glioblastoma.

Oridonin prevents oxidative stress-induced endothelial injury via promoting Nrf-2 pathway in ischaemic stroke

Oridonin, a natural diterpenoid compound extracted from a Chinese herb, has been proved to exert anti‐oxidative stress effects in various disease models. The aim of the present study was to investigate the protective effects of oridonin on oxidative stress‐induced endothelial injury in ischaemic stroke. We found oridonin repaired blood‐brain barrier (BBB) integrity presented with upregulation of tight junction proteins (TJ proteins) expression, inhibited the infiltration of periphery inflammatory cells and neuroinflammation and thereby reduced infarct volume in ischaemic stroke mice. Furthermore, our results showed that oridonin could protect against oxidative stress‐induced endothelial injury via promoting nuclear translocation of nuclear factor‐erythroid 2 related factor 2 (Nrf‐2). The specific mechanism could be the activation of AKT(Ser473)/GSK3β(Ser9)/Fyn signalling pathway. Our findings revealed the therapeutic effect and mechanism of oridonin in ischaemic stroke, which provided fundamental evidence for developing the extracted compound of Chinese herbal medicine into an innovative drug for ischaemic stroke treatment.

Increased In Vitro Intercellular Barrier Function of Lung Epithelial Cells Using Adipose-Derived Mesenchymal Stem/Stromal Cells

With the emergence of coronavirus disease-2019, researchers have gained interest in the therapeutic efficacy of mesenchymal stem/stromal cells (MSCs) in acute respiratory distress syndrome; however, the mechanisms of the therapeutic effects of MSCs are unclear. We have previously reported that adipose-derived MSCs (AD-MSCs) strengthen the barrier function of the pulmonary vessels in scaffold-based bioengineered rat lungs. In this study, we evaluated whether AD-MSCs could enhance the intercellular barrier function of lung epithelial cells in vitro using a transwell coculture system. Transepithelial electrical resistance (TEER) measurements revealed that the peak TEER value was significantly higher in the AD-MSC coculture group than in the AD-MSC non-coculture group. Similarly, the permeability coefficient was significantly decreased in the AD-MSC coculture group compared to that in the AD-MSC non-coculture group. Immunostaining of insert membranes showed that zonula occuldens-1 expression was significantly high at cell junctions in the AD-MSC coculture group. Moreover, cell junction-related gene profiling showed that the expression of some claudin genes, including claudin-4, was upregulated in the AD-MSC coculture group. Taken together, these results showed that AD-MSCs enhanced the barrier function between lung epithelial cells, suggesting that both direct adhesion and indirect paracrine effects strengthened the barrier function of lung alveolar epithelium in vitro.

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.

Severe acute pancreatitis concurrent with lethal rupture of cerebral aneurysm: A case report and review of the literature

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Severe acute pancreatitis with SIRS and MODS causes high mortality.

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First SAP concurrent with ruptured cerebral aneurysm case was reported in this article.

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Inflammation-induced blood-brain barrier impairment leads to cerebrovascular injury.

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Possible mechanism includes neuroinflammation and inflammation-induced vessel damage.

Introduction

With high incidence and mortality, severe acute pancreatitis (SAP) is an inflammatory disease of pancreas. When concurrent with systemic inflammatory response syndrome (SIRS), multiple organ failure syndrome (MODS) or pancreatic encephalopathy (PE), it will significantly augment the mortal rate. Herein, we report the first SAP case complicated with fatal rupture of cerebral aneurysm and pre-existing cerebral arteriovenous malformation; meanwhile, numerous examinations indicated the occurrence of SIRS and MODS.

Case presentation

A 34-year-old male was admitted for these complaints of fixed and continuous epigastric distending pain, nausea and vomiting for nearly 6 h after his greasy lunch. Imaging and experimental examinations indicated SAP concurrent with SIRS and MODS in this patient. Conventional therapies stabled him, but he developed unconscious for fatal rupture of cerebral aneurysm based on cerebral magnetic resonance imaging results. Subsequent treatments failed and this patient died from lethal systemic complications.

Discussion

After reviewed relevant literature in detail, we unveil the potential mechanisms in this case that systemic inflammation initiated by necrotic tissues of pancreas will disrupt blood-brain barrier (BBB), increase BBB permeability, trigger neuroinflammation and eventually damage cerebral vascular.

Conclusion

Therefore, to prevent lethal complications of PE or cerebral hemorrhage (CM) in severe pancreatitis, more attentions are recommended to be paid on identifying inflammation-induced brain dysfunction and applying prompt anti-inflammatory therapies.