抑瘤素M的研究进展

动脉粥样硬化(AS)是心血管疾病重要的发病基础,是涉及多方面的复杂病理过程,主要病理机制是慢性血管炎症反应、平滑肌细胞增殖与迁移、细胞凋亡及新血管形成等,许多与炎症相关的标志物已被作为监测AS和心血管疾病风险的新靶点,其中抑瘤素M(OSM)在AS中的作用逐渐受到重视。现已证实OSM除了在黑色素瘤、肝脏再生和慢性炎症如风湿性关节炎、肺和皮肤炎性疾病中具有生物效应,在AS疾病中也发挥作用,本文对OSM在AS发生发展中的作用进行了综述。     

The oncostatin M receptor/gp130 ligand murine oncostatin M induces apoptosis in adrenocortical Y-1 tumor cells

The effects of murine oncostatin M (mOSM) are specifically mediated by the heterodimeric oncostatin M receptor (OSMR)/gp130 receptor complex. In the current study we demonstrate that murine adrenocortical Y-1 tumor cells express the OSMR/gp130 complex. Incubation of Y-1 cells with 1 and 10 ng/ml mOSM induces cell death due to specific induction of apoptosis. Western blot analysis of Y-1 cells incubated with mOSM for 24 h revealed caspase-3 cleavage and poly(ADP-ribase) polymerase (PARP) cleavage. In a proliferation assay system, incubation of Y-1 cells with 0.01, 0.1, 1 and 10 ng/ml mOSM for 24 h resulted in a decrease in cell numbers to 99+/-2%, 84+/-9%, 50+/-7% and 43+/-5% respectively of untreated control (defined as 100%). Pretreatment of Y-1 cells with the Jak2 inhibitor AG490 (100 microM) rescued Y-1 cells from OSM-induced (10 ng/ml) cell death. Similarly, pretreatment of Y-1 cells with the general caspase inhibitor Z-VAD-FMK (42 microM) rescued Y-1 cells from OSM-induced (10 ng/ml) cell death. In summary, we show that adrenocortical Y-1 tumor cells express the OSMR/gp130 complex and that mOSM induces the Jak-STAT signaling cascade in these cells. Murine OSM in a dose-dependent manner induces apoptosis in adrenocortical Y-1 tumor cells. Apoptosis was demonstrated by caspase-3 cleavage and PARP cleavage. Rescue of Y-1 cells from mOSM-induced apoptosis by the Jak2 inhibitor, AG490, and the general caspase inhibitor, Z-VAD-FMK, demonstrates Jak activation and subsequent caspase activation to be essential for mOSM-induced apoptosis in adrenocortical Y-1 tumor cells. The putative role of OSM as an immunotherapeutic agent in human adrenocortical cancer remains to be elucidated.     

Secretion of oncostatin M by neutrophils in rheumatoid arthritis

OBJECTIVE: Neutrophils are known to express and release a large number of proinflammatory cytokines when they are stimulated by inflammatory stimuli. The objective of this study was to determine whether neutrophils express oncostatin M (OSM), a member of the interleukin-6 family of cytokines that has been implicated in the pathogenesis of inflammatory joint disease. METHODS: Neutrophils were isolated from the blood of healthy volunteer donors and from the blood and synovial fluid of patients with rheumatoid arthritis (RA). OSM levels were measured in cell extracts and in culture supernatants by Western blotting. Total RNA was isolated from control and granulocyte-macrophage colony-stimulating factor (GM-CSF)-treated neutrophils, and OSM messenger RNA levels were quantified by hybridization of a radiolabeled probe. RESULTS: GM-CSF stimulated a rapid and transient expression and release of OSM from blood neutrophils, which was more rapid than the expression and release from blood monocytes. A 28-kd protein was identified in cell extracts, but an additional 25-kd isoform was detected in culture supernatants. Synovial fluid neutrophils could not be stimulated to express OSM, but this cytokine was detected in cell-free supernatants at various levels. CONCLUSION: Blood neutrophils can be stimulated to express and rapidly release large quantities of OSM. We propose that this important cytokine is released from neutrophils as they infiltrate rheumatoid joints and, thus, contribute to the complex cytokine network that characterizes RA.     

Targeted disruption of oncostatin M receptor results in altered hematopoiesis

Oncostatin M (OSM) is a multifunctional cytokine that belongs to the interleukin 6 (IL-6) family. As OSM is expressed in adult as well as embryonic hematopoietic tissues, OSM has been considered to play a role in hematopoiesis. To uncover roles of OSM, we have generated mutant mice deficient in the OSM-specific receptor beta subunit (OSMR). While OSMR-/- mice were healthy and fertile, hematologic analysis of OSMR-/- mice demonstrated that the numbers of peripheral erythrocytes and platelets were reduced compared with wild-type mice. Consistent with this, progenitors of erythroid and megakaryocyte lineages were reduced in OSMR-/- bone marrow (BM), suggesting that OSM is required for the maintenance of erythroid and megakaryocyte progenitor pools in BM. To investigate whether OSM acts on the hematopoietic progenitors directly or indirectly, we performed BM transplantation experiments. The OSMR-/- mice, engrafted with wild-type BM cells, failed to produce erythrocytic and megakaryocytic progenitors to the levels in wild-type mice, indicating that OSM affects hematopoietic microenvironments. On the other hand, erythrocytic and megakaryocytic progenitors were reduced in the wild-type mice reconstituted with OSMR-/- BM cells. Thus, OSM regulates hematopoiesis in vivo by stimulating stromal cells as well as hematopoietic progenitors, in particular megakaryocytic and erythrocytic progenitors.     

Changes in the lymph node microenvironment induced by oncostatin M

Oncostatin M (OM) transforms the lymph node (LN) into a "super lymphoid organ" with 2 striking features: massive thymus-independent T-cell development and major expansion of the memory T-cell pool. We report that T-cell development in the LckOM LN is regulated by a cyclooxygenase-2 (COX-2)-dependent neoangiogenesis involving high endothelial venules (HEVs). That LN HEVs are particularlyrich in OM-receptor beta-chain provides aplausible explanation for the fact that extrathymic T-cell development in LckOM mice is limited to the LN. Moreover, we found that increased production of the CCL20 chemokine by LN stromal cells was instrumental in the expansion of the memory phenotype CD4 T-cell pool in LckOM mice. The generality of the latter finding was demonstrated by the fact that CCL20/CCR6 interactions increase the basal proliferation rate of CD62L(lo) CD4 T cells irrespective of their thymic (in non-OM-transgenic mice) or extrathymic (in LckOM mice) origin. To our knowledge, CCL20 is the first molecule found to increase the proliferation of memory phenotype CD4 T cells. These findings identify potential targets for the creation of thymic substitutes (LN HEVs) and for expansion of the CD4 memory T-cell compartment (CCL20).     

Hepatic differentiation induced by oncostatin M attenuates fetal liver hematopoiesis

Embryonic liver is a transient site for definitive hematopoiesis. Along with maturation of the bone marrow and spleen, hematopoietic cells relocate from the liver to their final destinations while the liver starts organizing its own structure and develops numerous metabolic functions toward adult. Recently, it was demonstrated that the signal exerted by oncostatin M (OSM) through gp130 plays a pivotal role in the maturation process of the liver both in vitro and in vivo. However, the molecular basis underlying the termination of embryonic hematopoiesis remains unknown. In this study, we report that primary culture of fetal hepatic cells from embryonic day 14.5 murine embryos supported expansion of blood cells from Lin-Sca-1(+)c-Kit+ cells, giving rise to myeloid, lymphoid, and erythroid lineages. Of interest, promotion of hepatic development by OSM and glucocorticoid strongly suppressed in vitro hematopoiesis. Consistent with these results, hepatic culture from the embryonic day 18.5 liver no longer supported hematopoiesis. These data together with the previous observations suggest that the signals exerted by OSM and glucocorticoid induce hepatic differentiation, which in turn terminate embryonic hematopoiesis and promote relocation of hematopoietic cells.     

Serum oncostatin M in multiple myeloma: association with prognostic factors

We report on five children with haematological malignancies who underwent allogeneic peripheral blood progenitor cell (PBPC) transplantation. PBPC were harvested from HLA-identical sibling donors after G-CSF (10 μg/kg/d s.c.) mobilization. Aphereses were carried out on day 5 after G-CSF using a Cobe Spectra blood cell separator. All PBPC allografts were cryopreserved before transplantation. The median of CD34⁺ cells and CD3⁺ cells infused were 14.1×10⁶/kg recipient body weight (range 4.92–22.3) and 2.40×10⁸/kg recipient body weight (range 0.54–4.82), respectively. Engraftment occurred in all cases. The median time to a neutrophil count >0.5×10⁹/l and a platelet count >20×10⁹/l were 15 and 14 d, respectively. The incidence of severe acute graft-versus-host disease was 20%. These data suggest that allogeneic PBPC transplantation might be an alternative to bone marrow transplantation in children.     

Detection of oncostatin M in synovial fluid from patients with rheumatoid arthritis

OBJECTIVE—To measure oncostatin M (OSM) in synovial fluid from patients with rheumatoid arthritis (RA) and osteoarthritis (OA).
METHODS—20 samples of synovial fluid from patients with RA and 10 samples from patients with OA were examined using an OSM specific sandwich ELISA.
RESULTS—OSM was detected at concentrations ranging from 2.36 to 901.82 pg/ml in 18 (90%) of 20 samples of synovial fluid from RA patients. There was no detectable OSM in synovial fluid from OA patients. In the RA patients, the OSM concentration in synovial fluid correlated significantly with the synovial fluid white blood cell count (r=0.67, p<0.01), but not with other laboratory parameters of disease activity.
CONCLUSION—These findings suggest that OSM may contribute to joint inflammation in RA.

     

Thrombocytopoietic response to immunothrombocytopenia in nude mice

Thrombocytopoiesis was evaluated in T cell-deficient nu/nu mice and in T cell-replete nu/+ controls to determine if abnormalities would be associated with the deficiency of T cells. Mice were studied in the unperturbed steady state and after acute immunothrombocytopenia was induced by an injection of guinea pig antimouse platelet serum (APS). The state of thrombocytopoiesis was determined from platelet counts, megakaryocyte size, megakaryocyte number, and numbers of Meg-CFC. Splenic lymphocytes were evaluated by response to the mitogens bacterial lipopolysaccharide (LPS), phytohemagglutinin (PHA), and concanavalin A (Con A). Hematocrits, reticulocyte counts, leukocyte counts, marrow cellularity, GM-CFC, and BFU-E also were measured. Steady state thrombocytopoiesis was identical in nu/nu and nu/+ mice. In response to an injection of APS, acute thrombocytopenia was followed by macromegakaryocytosis and rebound thrombocytosis in mice of both genotypes. Splenic Meg-CFC increased in nude mice after APS or an injection of normal guinea pig serum (NGpS), and splenic GM-CFC increased after APS. Neither Meg-CFC nor GM-CFC increased in the spleens of nu/+ mice, but they showed early transient increases in bone marrow that did not occur in nu/nu mice. Sporadic, but weak, mitogenic responses to PHA or Con A were occasionally observed with nu/nu spleen cells, but these did not correlate with the state of thrombocytopoiesis. The results demonstrated that platelet production was normal in nu/nu mice and that megakaryocytopoiesis and platelet production responded to the stimulus imposed by acute immunothrombocytopenia. Increases in megakaryocyte size and platelet production occurred independently of changes in numbers of Meg-CFC, GM- CFC, or BFU-E. A normal complement of T cells appears to be unnecessary for normal platelet production and its augmentation in response to the stimulus of acute immunothrombocytopenia in vivo.     

Serum oncostatin M in multiple myeloma: impact on disease severity and prognosis

Since high levels of serum IL-6 predict a poor prognosis of patients with multiple myeloma (MM), we investigated if a related cytokine, oncostatin M (OSM), correlates with clinical or biochemical findings or has prognostic significance in patients with MM. Among 82 newly diagnosed MM patients, OSM was detected in the sera in 45 (55%). Serum OSM had a borderline statistical correlation with serum IL-6 (r = 0.198, p = 0.074) and C-reactive protein (r = 0.199, p = 0.074) concentrations. However, OSM did not have prognostic significance alone or in combination with other factors. The median survival of patients with detectable serum OSM concentration was 41 months (range 2-124 months) and of OSM negative patients 35 months (1-75 months). Serum OSM concentration was not associated with clinical factors or severity of bone disease at diagnosis. We conclude that serum OSM concentration is not a prognostic factor in MM patients.     

抑瘤素M在高血糖致人主动脉平滑肌细胞增殖中的作用

目的 研究高血糖对人巨噬细胞中抑瘤素M表达的影响以及抑瘤素M对人主动脉平滑肌细胞增殖的影响.方法 采用佛波酯孵育人单核/巨噬细胞系THP-1细胞,诱导其分化为巨噬细胞.应用人细胞因子抗体芯片筛选出受高血糖(15 mmol/L)调控的人巨噬细胞源性细胞因子,并经Western blot和酶联免疫吸附试验(ELISA)技术验证.运用逆转录-聚合酶链反应(RT-PCR)明确人主动脉内皮细胞、平滑肌细胞及巨噬细胞中是否存在抑瘤素M受体GP130-OSMRβ二聚体及GP130-LIFR二聚体表达.运用细胞增殖实验(XTT法)研究抑瘤素M对人主动脉平滑肌细胞增殖的影响.采用单因素方差分析进行统计学分析.结果 佛波酯孵育48 h可诱导THP-1细胞分化为巨噬细胞.细胞因子芯片结果显示高血糖可上调抑瘤素M在巨噬细胞中的表达,并为Western blot及ELISA所证实.RT-PCR显示人主动脉内皮细胞、平滑肌细胞及巨噬细胞均可表达GP130-OSMRβ二聚体及GP130-LIFR二聚体.XTT法证实抑瘤素M可促进血管平滑肌细胞增殖,与0μg/L抑瘤素M(吸光度为0.468±0.032)相比,5μg/L(吸光度为0.503±0.026)、10μg/L(吸光度为0.520±0.027)、20μg/L抑瘤素M(吸光度为0.513±0.026)人主动脉平滑肌细胞增殖均明显增加(F=10.40,P<0.05).结论 高血糖可促进巨噬细胞中抑瘤素M的表达和分泌.抑瘤素M通过与人主动脉平滑肌细胞中的受体结合而促进血管平滑肌细胞的增殖,进而部分参与糖尿病大血管病变的发生发展.     

TNF-alpha regulates mouse fetal hepatic maturation induced by oncostatin M and extracellular matrices

Fetal hepatic maturation consists of multisteps and is regulated by several cytokines and cell-cell or cell-matrices interactions. In the mid-to-late fetal stage, hepatocytes have few metabolic functions associated with adult liver homeostasis. Cultured fetal hepatocytes acquire the expression of several mature liver-specific genes through stimulation with hepatic maturation factor oncostatin M (OSM) and matrigel. Tumor necrosis factor-alpha (TNFalpha) regulates fetal hepatic maturation stimulated by OSM and matrigel. TNFalpha suppressed expression of mature liver-specific genes such as tyrosine aminotransferase and apolipoproteins. In addition, the expression of hematopoietic cytokines and cyclin A2, repressed by OSM and matrigel, is induced by TNFalpha in the fetal hepatic cultures coincident with cell division. TNFalpha inhibited the induction of hepatocyte nuclear factor 4alpha induced by OSM and matrigel, suggesting that down-regulation of hepatocyte nuclear factor 4alpha expression is involved in the mechanism of suppression of hepatic maturation by TNFalpha. Interestingly, TNFalpha is expressed in the prenatal and postnatal liver but not in adult liver, whereas TNFR1, a TNFalpha receptor, is expressed in both fetal and adult livers. In conclusion, TNFalpha is a suppressive factor of hepatic maturation. The balance between hepatic maturation factor (OSM and extracellular matrices) and TNFalpha is important for liver development.     

Effects of Degree of Thrombocytopenia on Thrombocytopoietic Response

Rats were exchange transfused withplatelet-poor blood to reduce the numberof circulating platelets. When thrombocytopenia was moderate, the rate of platelet increase toward normal levels wasrelatively slow, whereas after severethrombocytopenia an early slow rate of increase was followed by a rapid rate. Itseems likely that the rapid platelet increase that begins about 36-48 hr afteracute, severe thrombocytopenia is engendered by a ploidy shift among megakaryocytes and by an increased input ofcells into the maturing population. Thebasis of the moderate increase in circulating platelets before 48 hr in severelythrombocytopenic rats and for about 5days in moderately thrombocytopenic ratsis less clear. Both peripheral changes inthe age distribution of the platelet population and in platelet depots, as well ashemopoietic changes in the marrow, probably contribute.

Submitted on September 14, 1973 Revised on February 8, 1974 Accepted on February 11, 1974     

Esculetin inhibits cartilage resorption induced by interleukin 1alpha in combination with oncostatin M

OBJECTIVE: To determine if a new inhibitor, esculetin (EST), can block resorption of cartilage. METHODS: Interleukin 1alpha (IL1alpha, 0.04-5 ng/ml) and oncostatin M (OSM, 0.4-50 ng/ml) were used to stimulate the release of proteoglycan and collagen from bovine nasal cartilage and human articular cartilage in explant culture. Proteoglycan and collagen loss were assessed by dimethylmethylene blue and hydroxyproline assays, respectively. Collagenase levels were measured by assay of bioactivity and by enzyme linked immunosorbent assay (ELISA). The effects of EST on the expression of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the transformed human chondrocyte cell line T/C28a4 were assessed by northern blot analysis. TIMP-1 protein levels were assayed by ELISA. The effect of EST on the MMP-1 promoter was assessed using a promoter-luciferase construct in transient transfection studies. RESULTS: EST inhibited proteoglycan and collagen resorption in a dose dependent manner with significant decreases seen at 66 microM and 100 microM EST, respectively. Collagenolytic activity was significantly decreased in bovine nasal cartilage cultures. In human articular cartilage, EST also inhibited IL1alpha + OSM stimulated resorption and decreased MMP-1 levels. TIMP-1 levels were not altered compared with controls. In T/C28a4 chondrocytes the IL1alpha + OSM induced expression of MMP-1, MMP-3, and MMP-13 mRNA was reduced to control levels by 250 microM EST. TIMP-1 mRNA levels were unaffected by EST treatment. All cytokine stimulation of an MMP-1 luciferase-promoter construct was lost in the presence of the inhibitor. CONCLUSION: EST inhibits degradation of bovine nasal cartilage and human articular cartilage stimulated to resorb with IL1alpha + OSM.