scholarly journals Sphingosine 1-Phosphate Receptor Blockade Affects Pro-Inflammatory Bone Marrow-Derived Macrophages and Relieves Mouse Fatty Liver Injury

2019 ◽  
Vol 20 (19) ◽  
pp. 4695 ◽  
Author(s):  
Jingjing Yang ◽  
Na Chang ◽  
Le Yang ◽  
Xiaofang Ji ◽  
Xuan Zhou ◽  
...  

Fatty liver injury is characterized by liver fat accumulation and results in serious health problems worldwide. There is no effective treatment that reverses fatty liver injury besides etiological therapy. Inflammation is an important macrophage-involving pathological process of liver injury. Here, we investigated the role of sphingosine 1-phosphate receptors (S1PRs) in fatty liver injury and explored whether S1PR2/3 blockade could cure fatty liver injury. A methionine-choline-deficient and a high-fat (MCDHF) diet was used to induce fatty liver injury, and the number of macrophages was evaluated by flow cytometry. Gene expressions were detected using RT-qPCR and cytometric bead array. In MCDHF-diet-fed mice, pro-inflammatory factor expressions were upregulated by fatty liver injury. The S1P level and S1PR2/3 expressions were significantly elevated. Moreover, increased S1P level and S1PR2/3 mRNA expressions were positively correlated with pro-inflammatory factor expressions in the liver. Furthermore, the number of pro-inflammatory macrophages (iMφ) increased in injured liver, and they were mainly bone-marrow-derived macrophages. In vivo, S1PR2/3 blockade decreased the amount of iMφ and inflammation and attenuated liver injury and fibrosis, although liver fat accumulation was unchanged. These data strongly suggest that anti-inflammatory treatment by blocking the S1P/S1PR2/3 axis attenuates fatty liver injury, which might serve as a potential target for fatty liver injury.

Blood ◽  
1996 ◽  
Vol 88 (2) ◽  
pp. 742-750 ◽  
Author(s):  
M Endo ◽  
PG Beatty ◽  
TM Vreeke ◽  
CT Wittwer ◽  
SP Singh ◽  
...  

A 10-year-old girl with paroxysmal nocturnal hemoglobinuria (PNH) received an infusion of syngeneic bone marrow without preparative marrow ablation or immunosuppression. Following transplant, the patient became asymptomatic in concordance with an increase in the percentage of peripheral blood cells with normal expression of glycosyl phosphatidylinositol-anchored proteins (GPI-AP). However, molecular analysis suggested engraftment of a relatively small number of donor stem cells and persistence of an abnormal stem cell with mutant PIG-A. During 17 months of observation, the percentage of cells with normal GPI-AP expression gradually decreased, while intravascular hemolysis progressively increased. Approximately 16.5 months post-transplant, the patient once again became symptomatic. Together, these results indicate that syngeneic marrow infusion provided a clinical benefit by increasing the proportion of erythrocytes with normal expression of GPI- anchored complement regulatory proteins without supplanting the abnormal stem cells. However, evidence of insidious disease progression following the marrow infusion implies that the abnormal stem cells have a survival advantage relative to the transplanted stem cells. Thus, these studies contribute in vivo data in support of the hypothesis that PNH arises as a consequence of a pathological process that selects for hematopoietic stem cells that are GPI-AP-deficient.


2015 ◽  
Vol 309 (12) ◽  
pp. G965-G974 ◽  
Author(s):  
Xiaoying Liu ◽  
Anne S. Henkel ◽  
Brian E. LeCuyer ◽  
Matthew J. Schipma ◽  
Kristy A. Anderson ◽  
...  

Fatty liver is associated with endoplasmic reticulum stress and activation of the hepatic unfolded protein response (UPR). Reduced hepatic expression of the UPR regulator X-box binding protein 1 spliced (XBP1s) is associated with human nonalcoholic steatohepatitis (NASH), and feeding mice a high-fat diet with fructose/sucrose causes progressive, fibrosing steatohepatitis. This study examines the role of XBP1 in nonalcoholic fatty liver injury and fatty acid-induced cell injury. Hepatocyte-specific Xbp1-deficient ( Xbp1−/−) mice were fed a high-fat/sugar (HFS) diet for up to 16 wk. HFS-fed Xbp1−/− mice exhibited higher serum alanine aminotransferase levels compared with Xbp1fl/fl controls. RNA sequencing and Gene Ontogeny pathway analysis of hepatic mRNA revealed that apoptotic process, inflammatory response, and extracellular matrix structural constituent pathways had enhanced activation in HFS-fed Xbp1−/− mice. Liver histology demonstrated enhanced injury and fibrosis but less steatosis in the HFS-fed Xbp1−/− mice. Hepatic Col1a1 and Tgfβ1 gene expression, as well as Chop and phosphorylated JNK (p-JNK), were increased in Xbp1−/− compared with Xbp1fl/fl mice after HFS feeding. In vitro, stable XBP1-knockdown Huh7 cells (Huh7-KD) and scramble control cells (Huh7-SCR) were generated and treated with palmitic acid (PA) for 24 h. PA-treated Huh7-KD cells had increased cytotoxicity measured by lactate dehydrogenase release, apoptotic nuclei, and caspase3/7 activity assays compared with Huh7-SCR cells. CHOP and p-JNK expression was also increased in Huh7-KD cells following PA treatment. In conclusion, loss of XBP1 enhances injury in both in vivo and in vitro models of fatty liver injury. We speculate that hepatic XBP1 plays an important protective role in pathogenesis of NASH.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4303-4303
Author(s):  
Chatchawin Assanasen ◽  
Rony Skaria ◽  
Maria G. Falcon ◽  
Victor Saldivar

Abstract Abstract 4303 The incidence of obesity and metabolic syndrome is on the rise. NAFLD is a chronic liver condition characterized by hepatic fat accumulation not due to other causes. NAFLD can progress to include a spectrum of inflammation, necrosis, fibrosis, and in some cases, cirrhosis. In its most extreme form, non-alcoholic steatohepatitis (NASH) and other liver dysfunction syndromes can cause significant toxicity and complicate the treatment of cancer patients receiving chemotherapy. Here we describe the complications of NAFLD transitioning to NASH acutely during induction therapy in an obese adolescent male with newly diagnosed pre-B ALL. A 15 year-old Hispanic male presented with a one-week history of lymphadenopathy. His past medical history included hypertension and NAFLD. No hepatosplenomegaly was noted at diagnosis. The initial laboratory evaluation revealed mild anemia, elevated LDH and uric acid as well as normal AST and ALT. Subsequent work-up including a bone marrow aspiration/biopsy revealed Pre-B ALL. The patient was started on induction therapy on a high-risk protocol receiving vincristine, daunorubicin, prednisone, and asparaginase. On Day 14 of induction, he complained of right upper quadrant pain, and leg paresthesias. Physical examination revealed jaundice, hepatomegaly, and loss of deep tendon reflexes in the lower extremities. Laboratory results revealed transaminitis and cholestatic jaundice with hyponatremia. Vincristine and daunorubicin were held. The patient was found to have SIADH and Grade IV peripheral neuropathy attributable to vincristine toxicity. Abdominal ultrasound showed diffuse fatty infiltration of the liver. Percutaneous needle liver biopsy revealed NASH with 70% pan-lobular steatosis, marked degeneration, mild cannalicular cholestasis, and stage 2–3/4 fibrosis. The patient completed 28 days of prednisone but did not receive any subsequent doses of vincristine during induction. The Day 14 bone marrow evaluation showed the patient to be in remission, and this was sustained through Day 29 despite only receiving 2 doses of vincristine (1.5mg/m2/dose) and daunorubicin (25mg/m2/dose), one dose of asparaginase (2500 IU/m2), and 28 days of prednisone (60mg/m2/day). The transaminitis resolved over the next month, as did the SIADH and neuropathy. It was hypothesized that the patient's baseline fatty liver was exacerbated by the prednisone diminishing hepatic metabolic capacity and enhancing chemotherapy related toxicities. He was removed from the study protocol and is being treated with 50% dose-reduced vincristine and avoidance of other hepatotoxic chemotherapies. He has liver biopsies performed after each cycle of chemotherapy to assess the degree of steatosis. Pediatric obesity is a growing problem. It is estimated that about 10% of children are affected by NAFLD/NASH. Higher rates are seen in Hispanics, obese populations, and type 2 diabetics. Serologic markers and imaging techniques have not proven to be effective at screening patients at risk for NAFLD/NASH. The gold standard for diagnosis is biopsy of liver tissue but may not be practical for all patients. Proven treatment strategies for NAFLD/NASH are similarly limited to lifestyle changes involving diet and exercise. Chemotherapy agents used in leukemia therapy consist of multiple agents that either rely on hepatic function for metabolic activation (cyclophosphamide, cytarabine, methotrexate) or elimination (vincristine, daunorubicin, mercaptopurine). Others including the antimetabolites (mercaptopurine, methotrexate, asparaginase, prednisone) have direct toxic effects on the liver. Limitations in the use of these standard agents severely hamper the therapeutic options for oncologists treating patients with leukemia. Although this is the only case report to our knowledge that describes chemotherapy inducing progression to NASH, clinicians are likely to continue to experience complications related to obesity, fatty liver, and metabolic syndrome as their incidence continues to rise worldwide. An essential component of leukemia therapy, corticosteroids have been shown to induce fat accumulation in the liver. This patient previously carried a diagnosis of fatty liver prior to treatment, but the rapid progression to NASH and subsequent hepatic dysfunction contributed significantly to his toxicities and future chemotherapeutic treatment options. Disclosures: Assanasen: Vidacare Corporation: Research Funding. Falcon:Vidacare Corporation: Research Funding.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Amber F. MacDonald ◽  
Ruby D. Trotter ◽  
Christopher D. Griffin ◽  
Austin J. Bow ◽  
Steven D. Newby ◽  
...  

Abstract Background In the last decade, graphene surfaces have consistently supported osteoblast development of stem cells, holding promise as a therapeutic implant for degenerative bone diseases. However, until now no study has specifically examined the genetic changes when stem cells undergo osteogenic differentiation on graphene. Results In this study, we provide a detailed overview of gene expressions when human mesenchymal stem cells (MSCs) derived from either adipose tissue (AD-MSCs) or bone marrow (BM-MSCs), are cultured on graphene. Genetic expressions were measured using osteogenic RT2 profiler PCR arrays and compared either over time (7 or 21 days) or between each cell source at each time point. Genes were categorized as either transcriptional regulation, osteoblast-related, extracellular matrix, cellular adhesion, BMP and SMAD signaling, growth factors, or angiogenic factors. Results showed that both MSC sources cultured on low oxygen graphene surfaces achieved osteogenesis by 21 days and expressed specific osteoblast markers. However, each MSC source cultured on graphene did have genetically different responses. When compared between each other, we found that genes of BM-MSCs were robustly expressed, and more noticeable after 7 days of culturing, suggesting BM-MSCs initiate osteogenesis at an earlier time point than AD-MSCs on graphene. Additionally, we found upregulated angiogenic markers in both MSCs sources, suggesting graphene could simultaneously attract the ingrowth of blood vessels in vivo. Finally, we identified several novel targets, including distal-less homeobox 5 (DLX5) and phosphate-regulating endopeptidase homolog, X-linked (PHEX). Conclusions Overall, this study shows that graphene genetically supports differentiation of both AD-MSCs and BM-MSCs but may involve different signaling mechanisms to achieve osteogenesis. Data further demonstrates the lack of aberrant signaling due to cell-graphene interaction, strengthening the application of specific form and concentration of graphene nanoparticles in bone tissue engineering. Graphic abstract


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5805-5805
Author(s):  
Lukun Zhou ◽  
Shuang Liu ◽  
Chuanyi M. Lu ◽  
Jianfeng Yao ◽  
Yuyan Shen ◽  
...  

Abstract Liver injury associated with veno-occlusive disease and graft-versus-host disease (GVHD) is a frequent and severe complication of hematopoietic stem cell transplantation, and remains an important cause of transplant-related mortality. Bone marrow derived mesenchymal stem cells (MSCs) have been evaluated for the prevention and treatment of refractory GVHD. However, poor cell viability has limited the therapeutic capacity of mesenchymal stromal cell therapy in vivo. In this study, we genetically engineered C57BL/6 mouse bone marrow MSCs using ex vivo retroviral transduction to overexpress Akt1, a serine threonine kinase and pro-survival signal protein, and tested the hypothesis that Akt1-expressing MSCs (Akt1-MSCs) are more resistant to apoptosis and can ameliorate acute liver injury induced by concanavalin A (ConA) in BALB/c mice. Cell proliferation and apoptosis analyses showed that, under both regular culture and high concentration IFN-γ (100 ng/mL) stimulation conditions, Akt1-GFP-MSCs had proliferation and survival (anti-apoptotic) advantages with down-regulated apoptosis pathways, compared to control GFP-MSCs. Twenty-four hours after receiving lethal dose of ConA (40 mg/kg, intravenous) (N=10 each group), no mouse survived, with or without 1x106 Akt1-MSCs or GFP-MSCs administration (intravenous); however, 3 and 1 survived in the 5×106 Akt1-MSCs group and 5×106 GFP-MSCs groups, respectively. In subsequent sub-lethal dose ConA (20 mg/kg) experiments, compared to GFP-MSCs, mice received Akt1-MSCs administration had significantly lower serum AST, ALT, TNF-α and IFN-γ levels and less histopathological abnormalities. In addition, Akt1-MSCs treated mice had significantly higher serum concentrations of IL-10, vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). In vivo imaging showed that, hepatic fluorescence signal in sub-lethal ConA+Akt1-MSCs group was significantly stronger than ConA+GFP-MSCs group on day 0, and persisted up to 14 days, whereas the signal in ConA+GFP-MSCs, Akt1-MSCs and GFP-MSCs groups was negligible on both day 7 and day 14. Thus, bone marrow derived MSCs genetically enhanced with Akt1 had survival advantage in vitro and in vivo, and have the potential to be a potent therapy for prevention and amelioration of GVHD-associated liver impairment. Further translational pre-clinical studies are ongoing to further determine the efficacy, dosage and timing of administration of Akt1-MSCs in animal models. Disclosures No relevant conflicts of interest to declare.


2019 ◽  
Vol 21 (1) ◽  
Author(s):  
Lukun Zhou ◽  
Shuang Liu ◽  
Zhao Wang ◽  
Jianfeng Yao ◽  
Wenbin Cao ◽  
...  

Abstract Background Liver injury associated with acute graft-versus-host disease (aGVHD) is a frequent and severe complication of hematopoietic stem cell transplantation and remains a major cause of transplant-related mortality. Bone marrow-derived mesenchymal stem cells (BM-MSCs) has been proposed as a potential therapeutic approach for aGVHD. However, the therapeutic effects are not always achieved. In this study, we genetically engineered C57BL/6 mouse BM-MSCs with AKT1 gene and tested whether AKT1-MSCs was superior to control MSCs (Null-MSCs) for cell therapy of liver aGVHD. Results In vitro apoptosis analyses showed that, under both routine culture condition and high concentration interferon-γ (IFN-γ) (100ng/mL) stimulation condition, AKT1-MSCs had a survival (anti-apoptotic) advantage compared to Null-MSCs. In vivo imaging showed that AKT1-MSCs had better homing capacity and longer persistence in injured liver compared to Null-MSCs. Most importantly, AKT1-MSCs demonstrated an enhanced immunomodulatory function by releasing more immunosuppressive cytokines, such as IL-10. Adoptive transfer of AKT1-MSCs mitigated the histopathological abnormalities of concanavalin A(ConA)-induced liver injury along with significantly lowered serum levels of ALT and AST. The attenuation of liver injury correlated with the decrease of TNF-α and IFN-γ both in liver tissue and in the serum. Conclusions In summary, BM-MSCs genetically modified with AKT1 has a survival advantage and an enhanced immunomodulatory function both in vitro and in vivo and thus demonstrates the therapeutic potential for prevention and amelioration of liver GVHD and other immunity-associated liver injuries.


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