scholarly journals PPARβ/δ Agonist Alleviates Diabetic Osteoporosis via Regulating M1/M2 Macrophage Polarization

Author(s):  
Miao Chen ◽  
Weimin Lin ◽  
Rui Ye ◽  
Jianru Yi ◽  
Zhihe Zhao

Diabetic osteoporosis is a common complication in diabetic patients, leading to increased fracture risk and impaired bone healing. As a member of the peroxisome proliferator-activated receptor (PPAR) family, PPARβ/δ agonist is suggested as a therapeutic target for the treatment of metabolic syndrome, and has been reported to positively regulate bone turnover by improving osteogenesis. However, its regulatory role in diabetic osteoporosis has not been reported yet. Here, we explored the therapeutic effects and potential mechanisms of PPARβ/δ agonist to the osteoporotic phenotypes of diabetic mice. Our results indicated that the osteoporotic phenotypes could be significantly ameliorated in diabetic mice by the administration of PPARβ/δ agonists. In vitro experiments suggested that PPARβ/δ agonist treatment could alleviate the abnormal increase of osteoclast activity in diabetic mice by rectifying high glucose-mediated macrophage dysfunction instead of directly inhibiting osteoclast differentiation. Mechanistically, Angptl4 may act as a downstream target of PPARβ/δ to regulate macrophage polarization. In conclusion, our study demonstrates the potential of PPARβ/δ agonist as a therapeutic target for the treatment of osteoporosis and immune homeostasis disorder in diabetic patients.

2021 ◽  
Author(s):  
Hogjuan Ning ◽  
Haixu Chen ◽  
Jingyu Deng ◽  
Chun Xiao ◽  
Lina Shan ◽  
...  

Abstract Background Exosomes are considered a substitute for stem cell-based therapy for myocardial infarction (MI). FNDC5, a transmembrane protein located in the cytoplasm, plays a crucial role in inflammation diseases and MI repair. Furthermore, our previous study found that FNDC5 pre-conditioning bone marrow-derived mesenchymal stem cells (BMMSCs) could secreted more exosomes, but little was known on MI repair. Methods Exosomes isolated from BMMSCs with or without FNDC5-OV were injected into infarcted hearts. Then, cardiomyocytes apoptosis, and inflammation responses were detected. Furthermore, exosomes were administrated to RAW264.7 macrophage with LPS treatment to investigate its effect on inflammation and macrophage polarization. Results Compared with MSCs-Exo, FNDC5-MSCs-Exo had superior therapeutic effects on anti-inflammation and anti-apoptosis, as well as polarizing M2 macrophage in vivo. Meanwhile, the in vitro results also showed that FNDC5-MSCs–Exo decreased pro-inflammatory secretion and increased anti-inflammatory secretion under LPS stimulation, which partly depressed NF-κB signaling pathway and upregulated Nrf2/HO-1 Axis. Conclusions FNDC5-BMMSCs-derived exosomes play anti-inflammation effects and promote M2 macrophage polarization via NF-κB signaling pathway and Nrf2/HO-1 Axis, which may develop a promising cell-free therapy for MI.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Hongjuan Ning ◽  
Haixu Chen ◽  
Jingyu Deng ◽  
Chun Xiao ◽  
Moyan Xu ◽  
...  

Abstract Background Exosomes are considered a substitute for stem cell-based therapy for myocardial infarction (MI). FNDC5, a transmembrane protein located in the cytoplasm, plays a crucial role in inflammation diseases and MI repair. Furthermore, our previous study found that FNDC5 pre-conditioning bone marrow-derived mesenchymal stem cells (BMMSCs) could secrete more exosomes, but little was known on MI repair. Methods Exosomes isolated from BMMSCs with or without FNDC5-OV were injected into infarcted hearts. Then, cardiomyocytes apoptosis and inflammation responses were detected. Furthermore, exosomes were administrated to RAW264.7 macrophage with LPS treatment to investigate its effect on inflammation and macrophage polarization. Results Compared with MSCs-Exo, FNDC5-MSCs-Exo had superior therapeutic effects on anti-inflammation and anti-apoptosis, as well as polarizing M2 macrophage in vivo. Meanwhile, the in vitro results also showed that FNDC5-MSCs-Exo decreased pro-inflammatory secretion and increased anti-inflammatory secretion under LPS stimulation, which partly depressed NF‐κB signaling pathway and upregulated Nrf2/HO-1 Axis. Conclusions FNDC5-BMMSCs-derived exosomes play anti-inflammation effects and promote M2 macrophage polarization via NF-κB signaling pathway and Nrf2/HO-1 Axis, which may develop a promising cell-free therapy for MI.


2015 ◽  
Vol 35 (6) ◽  
pp. 2213-2222 ◽  
Author(s):  
Shishui Lin ◽  
Meiguang Qiu ◽  
Jianting Chen

Background/Aims: Osteoclasts (OC) originate from monocytes/macrophages and play a critical role in the development of ankylosing spondylitis (AS). Receptor activator of NF-kB ligand (RANKL) is critical for the differentiation and maturation of OC from monocytes/macrophages, the underlying mechanisms of which processes have not been completely elucidated. Interleukin 4 (IL-4) attenuates the pathogenesis of AS via ill-defined mechanisms. Methods: We used a proteoglycan-induced arthritis (PGIA) model in Balb/c mice to study AS in humans. We injected IL-4 into the articular cavity and evaluated its effects on PGIA by incidence of arthritis, clinical and pathological arthritis severity and PET tracer uptake. We isolated and analyzed the number and polarization of macrophages in the articular cavity before and after IL-4 treatment. We analyzed RANKL levels in macrophage subtypes. We then isolated bone-marrow derived macrophages and treated them with IL-4 in vitro, with or without histone deacetylase inhibitors trichostatin A (TSA), and then analyzed the polarization of cultured macrophages before and after IL-4 treatment and RANKL levels in macrophage subtypes. Results: IL-4 treatment decreased the incidence and severity of arthritis in a mouse AS model, and polarized macrophages from a classical M1 subtype to an M2 subtype in vivo and in vitro. RANKL was predominantly produced by M1, but not by M2 macrophages. IL-4-mediated inhibition of RANKL in macrophages was abolished by TSA. Conclusion: Our data suggest that the therapeutic effects of IL-4 on AS may result from a M1-to-M2 macrophage polarization and its inhibition of RANKL expression on macrophages, possibly through enhanced histone deacetylation.


2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Chui Yiu Bamboo Chook ◽  
Francis M. Chen ◽  
Gary Tse ◽  
Fung Ping Leung ◽  
Wing Tak Wong

Abstract Cardiovascular disease is a major cause of mortality in diabetic patients due to the heightened oxidative stress and pro-inflammatory state in vascular tissues. Effective approaches targeting cardiovascular health for diabetic patients are urgently needed. Crocodile blood, an emerging dietary supplement, was suggested to have anti-oxidative and anti-inflammatory effects in vitro, which have yet to be proven in animal models. This study thereby aimed to evaluate whether crocodile blood can protect vascular function in diabetic mice against oxidation and inflammation. Diabetic db/db mice and their counterparts db/m+ mice were treated daily with crocodile blood soluble fraction (CBSF) or vehicle via oral gavage for 4 weeks before their aortae were harvested for endothelium-dependent relaxation (EDR) quantification using wire myograph, which is a well-established functional study for vascular function indication. Organ culture experiments culturing mouse aortae from C57BL/6 J mice with or without IL-1β and CBSF were done to evaluate the direct effect of CBSF on endothelial function. Reactive oxygen species (ROS) levels in mouse aortae were assessed by dihydroethidium (DHE) staining with inflammatory markers in endothelial cells quantified by quantitative polymerase chain reaction (qPCR). CBSF significantly improved deteriorated EDR in db/db diabetic mice through both diet supplementation and direct culture, with suppression of ROS level in mouse aortae. CBSF also maintained EDR and reduced ROS levels in mouse aortae against the presence of pro-inflammatory IL-1β. Under the pro-inflammatory state induced by IL-1β, gene expressions of inflammatory cytokines were downregulated, while the protective transcripts UCP2 and SIRT6 were upregulated in endothelial cells. Our study suggests a novel beneficial effect of crocodile blood on vascular function in diabetic mice and that supplementation of diet with crocodile blood may act as a complementary approach to protect against vascular diseases through anti-oxidation and anti-inflammation in diabetic patients. Graphical abstract


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Guodong Li ◽  
Chung-Nga Ko ◽  
Dan Li ◽  
Chao Yang ◽  
Wanhe Wang ◽  
...  

AbstractImpaired wound healing and ulcer complications are a leading cause of death in diabetic patients. In this study, we report the design and synthesis of a cyclometalated iridium(III) metal complex 1a as a stabilizer of hypoxia-inducible factor-1α (HIF-1α). In vitro biophysical and cellular analyses demonstrate that this compound binds to Von Hippel-Lindau (VHL) and inhibits the VHL–HIF-1α interaction. Furthermore, the compound accumulates HIF-1α levels in cellulo and activates HIF-1α mediated gene expression, including VEGF, GLUT1, and EPO. In in vivo mouse models, the compound significantly accelerates wound closure in both normal and diabetic mice, with a greater effect being observed in the diabetic group. We also demonstrate that HIF-1α driven genes related to wound healing (i.e. HSP-90, VEGFR-1, SDF-1, SCF, and Tie-2) are increased in the wound tissue of 1a-treated diabetic mice (including, db/db, HFD/STZ and STZ models). Our study demonstrates a small molecule stabilizer of HIF-1α as a promising therapeutic agent for wound healing, and, more importantly, validates the feasibility of treating diabetic wounds by blocking the VHL and HIF-1α interaction.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A923-A923
Author(s):  
Víctor Cortés-Morales ◽  
Juan Montesinos ◽  
Luis Chávez-Sánchez ◽  
Sandra Espíndola-Garibay ◽  
Alberto Monroy-García ◽  
...  

BackgroundMacrophages are immunological cells that sense microenvironmental signals that may result in the polarized expression of either proinflammatory (M1) or anti-inflammatory (M2) phenotype.1 Macrophages M2 are present in tumoral microenvironment and their presence in patients with cervical cancer (CeCa) is related with less survival.2Mesenchymal Stromal Cells (MSCs) are also present in tumor microenvironment of cervical cancer (CeCa-MSC), which have shown immunoregulatory effects over CD8 T cells, decreasing their cytotoxic effect against tumoral cells.3 Interestingly, MSCs from bone marrow (BM-MSC) decrease M1 and increase M2 macrophage polarization in an in vitro coculture system.4 Macrophages and MSCs are present in microenvironment of cervical cancer, however it is unknown if MSCs play a role in macrophage polarization. In the present study, we have evaluated the immunoregulatory capacity of CeCa-MSCs to induce macrophage polarization.MethodsCD14 monocytes were isolated from peripheral blood and cultivated in the absence or presence of MSCs from BM, normal cervix (NCx) and CeCa. Two culture conditions were included, in the presence of induction medium to favors M1 (GM-CSF, LPS and IFNg) or M2 (M-CSF, IL-4 and IL-13) macrophage polarization. M1 (HLA-DR, CD80, CD86 and IFNg) or M2 (CD14, CD163, CD206, IDO and IL-10) macrophage molecular markers were evaluated by flow cytometry. Finally, we evaluated concentration of IL-10 and TNFa in conditioned medium form all coculture conditions.ResultsWe observed that CeCa-MSCs and BM-MSCs in presence of M1 induction medium, decreased M1 macrophage markers (HLA-II, CD80, CD86 and IFNg), and increase the expression of CD14 (M2 macrophage marker). Interestingly, in presence of M2 induction medium, BM-MSCs and CaCe-MSCs but not CxN-MSC increased CD163, CD206, IDO and IL-10 (M2 macrophage markers). We observed a decreased concentration of TNFa in the supernatant medium from all cocultures with MSCs, but only in presence of CeCa-MSCs, increased IL-10 concentration was detected in such cocultures.ConclusionsIn contrast to NCx-MSCs, CeCa-MSCs similarly to BM-MSCs have in vitro capacity to decrease M1 and increase M2 macrophage phenotype.AcknowledgementsAcknowledgments The authors are indebted to gratefully acknowledge to CONACYT (Grant No. 272793) and IMSS (Grant no. 1731) for support to Juan J. Montesinos research.ReferencesMartinez FO, Gordon S. The M1 and M2 paradigm of macrophage activation: time for reassessment. F1000Prime Rep 2014;6-13.Petrillo M, Zannoni GF, Martinelli E, et al. Polarization of tumor-associated macrophages toward M2 phenotype correlates with poor response to chemoradiation and reduced survival in patients with locally advanced cervical cancer. PLoS One 2015;10: e0136654.Montesinos JJ, Mora-García Mde L, et al. In vitro evidence of the presence of mesenchymal stromal cells in cervical cancer and their role in protecting cancer cells from cytotoxic T cell activity. Stem Cells Dev 2013;22:2508-2519.Vasandan AB, Jahnavi S, Shashank C. Human mesenchymal stem cells program macrophage plasticity by altering their metabolic status via a PGE 2-dependent mechanism. Sci Rep 2016;6:38308.


Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 855
Author(s):  
Ekaterina A. Litvinova ◽  
Victoria D. Bets ◽  
Natalya A. Feofanova ◽  
Olga V. Gvozdeva ◽  
Kseniya M. Achasova ◽  
...  

Intestinal mucus protects epithelial and immune cells from the gut resident microorganisms, and provides growth-promoting factors as mucus-derived O-glycans for beneficial bacteria. A lack of intestinal protective mucus results in changes in the commensal microflora composition, mucosal immune system reprogramming, and inflammation. Previous work has shown that fucose, the terminal glycan chain component of the intestinal glycoprotein Mucin2, and fucoidan polysaccharides have an anti-inflammatory effect in some mouse models of colitis. This study evaluates the effect of fucose on reproductive performance in heterozygous mutant Muc2 female mice. We found that even though Muc2+/− females are physiologically indistinguishable from C57Bl/6 mice, they have a significantly reduced reproductive performance upon dietary fucose supplementation. Metagenomic analysis reveals that the otherwise healthy wild-type siblings of Muc2−/− animals have reduced numbers of some of the intestinal commensal bacterial species, compared to C57BL/6 mice. We propose that the changes in beneficial microflora affect the immune status in Muc2+/− mice, which causes implantation impairment. In accordance with this hypothesis, we find that macrophage polarization during pregnancy is impaired in Muc2+/− females upon addition of fucose. Metabolic profiling of peritoneal macrophages from Muc2+/− females reveals their predisposition towards anaerobic glycolysis in favor of oxidative phosphorylation, compared to C57BL/6-derived cells. In vitro experiments on phagocytosis activity and mitochondrial respiration suggest that fucose affects oxidative phosphorylation in a genotype-specific manner, which might interfere with implantation depending on the initial status of macrophages. This hypothesis is further confirmed in BALB/c female mice, where fucose caused pregnancy loss and opposed implantation-associated M2 macrophage polarization. Taken together, these data suggest that intestinal microflora affects host immunity and pregnancy outcome. At the same time, dietary fucose might act as a differential regulator of macrophage polarization during implantation, depending on the immune status of the host.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A900-A900
Author(s):  
Ronghua Zhang ◽  
Tienan Wang ◽  
Qing Lin

BackgroundMacrophage is an important component in tumor microenvironment (TME) and plays multiple roles in tumor initiation, progression and metastases. In response to various stimuli within TME, macrophage exhibits high level of functional heterogeneity. There are two distinct groups of macrophages: M1 macrophage exhibits pro-inflammatory phenotype with high levels of TNF-a, IL-6, and IL-1ß, while M2 macrophage displays immune suppressive phenotype with high levels of anti-inflammatory cytokines such as IL-10 and TGF-ß. In response to the M2 cytokines, myeloid cells within the TME further acquire higher expression of PD-L1 and thus inactivate T cells. M2 cytokines can also directly inhibit T cell activation. As a result, re-polarizing M2 macrophages becomes a key concept for cancer immunotherapy. The NLRP3 inflammasome is acquired by macrophages to fight against endogenous danger signals. Macrophage NLRP3 activation has been observed in several tumor models, but the function of NLRP3 on macrophage polarity remains controversial. Inflammasome activation with IL-1ß/IL-18 secretion was reported to promote M1 polarization. However, NLRP3 activation was also reported to promote M2 polarity through up-regulation of IL4 in asthma modelMethodsHere, we have established an in vitro human macrophage NLRP3 activation system (figure 1), coupled with M2 macrophage polarization assay, to dissect the role of NLRP3 in macrophage phenotype.ResultsOur results indicate that NLRP3 activation restrained M2 phenotype and further enhanced T cell activation in an M2/T cell co-culture system (figure 2).Abstract 847 Figure 1Inflammasome activation polarize M2 macrophage intUse LPS/ATP to stimulate NLRP3 in M2 macrophage and demonstrate NLRP3 activation could reduce CD163 and increase CD86Abstract 847 Figure 2Inflammasome in M2 rescue T cell activationestablish M2/T co-culture system in vitro to demonstrate M2 could suppress T activation while Inflammatory M2 could partial rescue the suppressive phenotypeConclusionsInflammasome could be the potential target for cancer by modulating T cell activation through macrophage polarization regulation


2021 ◽  
Vol 12 ◽  
Author(s):  
Nisha R. Dhanushkodi ◽  
Ruchi Srivastava ◽  
Pierre-Gregoire A. Coulon ◽  
Swayam Prakash ◽  
Soumyabrata Roy ◽  
...  

Herpes simplex virus 1 (HSV-1) infects the cornea and caused blinding ocular disease. In the present study, we evaluated whether and how a novel engineered version of fibroblast growth factor-1 (FGF-1), designated as TTHX1114, would reduce the severity of HSV-1-induced and recurrent ocular herpes in the mouse model. The efficacy of TTHX1114 against corneal keratopathy was assessed in B6 mice following corneal infection with HSV-1, strain McKrae. Starting day one post infection (PI), mice received TTHX1114 for 14 days. The severity of primary stromal keratitis and blepharitis were monitored up to 28 days PI. Inflammatory cell infiltrating infected corneas were characterized up to day 21 PI. The severity of recurrent herpetic disease was quantified in latently infected B6 mice up to 30 days post-UVB corneal exposure. The effect of TTHX1114 on M1 and M2 macrophage polarization was determined in vivo in mice and in vitro on primary human monocytes-derived macrophages. Compared to HSV-1 infected non-treated mice, the infected and TTHX1114 treated mice exhibited significant reduction of primary and recurrent stromal keratitis and blepharitis, without affecting virus corneal replication. The therapeutic effect of TTHX1114 was associated with a significant decrease in the frequency of M1 macrophages infiltrating the cornea, which expressed significantly lower levels of pro-inflammatory cytokines and chemokines. This polarization toward M2 phenotype was confirmed in vitro on human primary macrophages. This pre-clinical finding suggests use of this engineered FGF-1 as a novel immunotherapeutic regimen to reduce primary and recurrent HSV-1-induced corneal disease in the clinic.


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