IL-37 inhibits the maturation of dendritic cells through the IL-1R8-TLR4-NF-κB pathway

Mature dendritic cells (DCs) play a pathogenic role in atherosclerosis. Our previous study demonstrated that exogenous interleukin (IL)-37 suppresses the maturation of DCs, induces the T-regulatory (Treg) cell response, and attenuates atherosclerosis in ApoE^−/− mice. The aim of the present study was to explore the molecular mechanism of IL-37 on the maturation of DCs throughout the development of atherosclerosis. The expression of interleukin-1 receptor 8 (IL-1R8), which is a single Ig-domain receptor that was recently found to be pivotal for the extracellular function of IL-37, Toll-like receptor (TLR) 4 and p65, was measured in ApoE^−/− mice and IL-37 transgenic (IL-37tg) ApoE^−/− mice. IL-1R8 was mainly expressed in aortic plaque-infiltrated DCs and at significantly higher levels in IL-37tg atherosclerotic mice, accompanied by lower levels of TLR4 and p65. Furthermore, IL-37 eliminated the maturation of DCs induced by oxidized low-density lipoprotein (oxLDL) and caused marked upregulation of IL-1R8 in vitro and downregulation of TLR4 and p65, which was consistent with the experiments in mice. However, the inhibitory effect of IL-37 on the maturation of DCs in vitro was abolished when IL-37 was used to treat DCs isolated from IL-1R8-deficient and TLR4-deficient mice. Therefore, this study indicated that IL-37 inhibited the maturation of DCs via the IL-1R8-TLR4-NF-κB pathway and attenuated atherosclerosis in ApoE^−/− mice.     

Butanol Extract of Acanthopanax senticosus (Rupr. et Maxim.) Harms Alleviates Atherosclerosis in Apolipoprotein E-Deficient Mice Fed a High-Fat Diet

This study investigated the effect of butanol extract of AS (ASBUE) on atherosclerosis in apolipoprotein E-deficient (ApoE^−/−) mice. The mice were administered ASBUE (390 or 130 mg/kg/day) or rosuvastatin (RSV) via oral gavage for eight weeks. In ApoE^−/− mice, ASBUE suppressed the abnormal body weight gain and improved serum and liver biochemical indicators. ASBUE remarkably reduced the aortic plaque area, improved liver pathological conditions, and lipid metabolism abnormalities, and altered the intestinal microbiota structure in ApoE^−/− mice. In the vascular tissue of ASBUE-treated mice, P-IKKβ, P-NFκB, and P-IκBα levels tended to decrease, while IκB-α increased in high fat-diet-fed atherosclerotic mice. These findings demonstrated the anti-atherosclerotic potential of ASBUE, which is mediated by the interaction between the gut microbiota and lipid metabolism and regulated via the Nuclear Factor-kappa B (NF-κB) pathway. This work paves the groundwork for subsequent studies to develop innovative drugs to treat atherosclerosis.     

Immune Response against Hamster Erythrocytes in the Low-Responder Mouse Strains

C57BL/6 and AKR mice were treated with hamster erythrocytes (HRBC) in complete Freund's adjuvant (CFA) or incomplete Freund's adjuvant (IFA) and the development of delayed hypersensitivity and antibody production were examined. 1) Delayed hypersensitivity against HRBC antigen, as determined by the peritoneal macrophage disappearance test, was detected in mice sensitized with HRBC in CFA but not in those sensitized with HRBC in IFA. 2) Antibody production against HRBC or hapten TNP after a booster injection of HRBC or trinitrophenylated HRBC (TNP-HRBC) in saline was enhanced by pretreatment with HRBC in CFA or IFA. 3) Delayed hypersensitivity was not detectable after a booster sensitization with HRBC in CFA in mice which had been pretreated with HRBC in IFA 2 weeks earlier. In the mice treated with both HRBC in IFA (day ?21) and in CFA (day ?7), however, an enhanced antibody production against HRBC or TNP was detected after an intravenous injection with HRBC or TNP-HRBC in saline (day 0). These results suggest that sensitized effector lymphocytes in delayed hypersensitivity and helper cells in antibody production may be derived from the same pool of unprimed T cells. The pool of unprimed T cells with a capacity to differentiate into either type of primed T cells may be exhausted after pretreatment with the antigen in IFA, and the primed helper T cells may not be able to differentiate into sensitized lymphocytes even after sensitization with the antigen in CFA, which favors development of delayed hypersensitivity in normal controls.     

Perilipin 5 deficiency promotes atherosclerosis progression through accelerating inflammation,apoptosis, and oxidative stress

Excessive plasma triglyceride (TG) and cholesterol levels promote the progression of several prevalent cardiovascular risk factors, including atherosclerosis, which is a leading death cause. Perilipin 5 (Plin5), an important perilipin protein, is abundant in tissues with very active lipid catabolism and is involved in the regulation of oxidative stress. Although inflammation and oxidative stress play a critical role in atherosclerosis development, the underlying mechanisms are complex and not completely understood. In the present study, we demonstrated the role of Plin5 in high-fat-diet-induced atherosclerosis in apolipoprotein E null (ApoE^−/−) mice. Our results suggested that Plin5 expressions increased in the artery tissues of ApoE^−/− mice. ApoE/Plin5 double knockout (ApoE^−/−Plin5^−/−) exacerbated severer atherogenesis, accompanied with significantly disturbed plasma metabolic profiles, such as elevated TG, total cholesterol, and low-density lipoprotein cholesterol levels and reduced high-density lipoprotein cholesterol contents. ApoE^−/−Plin5^−/− exhibited a higher number of inflammatory monocytes and neutrophils, as well as overexpression of cytokines and chemokines linked with an inflammatory response. Consistently, the IκBα/nuclear factor kappa B pathway was strongly activated in ApoE^−/−Plin5^−/−. Notably, apoptosis was dramatically induced by ApoE^−/−Plin5^−/−, as evidenced by increased cleavage of Caspase-3 and Poly (ADP-ribose) polymerase-2. In addition, ApoE^−/−Plin5^−/− contributed to oxidative stress generation in the aortic tissues, which was linked with the activation of phosphatidylinositol 3-kinase/protein kinase B and mitogen-activated protein kinases pathways. In vitro, oxidized low-density lipoprotein (ox-LDL) increased Plin5 expression in RAW264.7 cells. Its knockdown enhanced inflammation, apoptosis, oxidative stress, and lipid accumulation, while promotion of Plin5 markedly reduced all the effects induced by ox-LDL in cells. These studies strongly supported that Plin5 could be a new regulator against atherosclerosis, providing new insights on therapeutic solutions.     

Transgenic CGI-58 expression in macrophages alleviates the atherosclerotic lesion development in ApoE knockout mice

Comparative Gene Identification-58 (CGI-58), as an adipose triglyceride lipase (ATGL) activator, strongly increases ATGL-mediated triglyceride (TG) catabolism. Previous studies have shown that CGI-58 affects intestinal cholesterol homeostasis independently of ATGL activity. Therefore, we hypothesized that CGI-58 was involved in macrophage cholesterol metabolism and consequently atherosclerotic lesion formation. Here, we generated macrophage-specific CGI-58 transgenic mice (Mac-CGI-58 Tg) using an SRA promoter, which was further mated with ApoE^−/− mice to create litters of CGI-58 Tg/ApoE^−/− mice. These CGI-58 Tg/ApoE^−/− mice exhibited an anti-atherosclerosis phenotype compared with wild type (WT) controls (CGI-58 WT/ApoE^−/−), illustrated by less plaque area in aortic roots. Moreover, macrophage-specific CGI-58 overexpression in mice resulted in up-regulated levels of plasma total cholesterol and HDL-cholesterol. Consequently, higher expression levels of PPARa, PPARγ, LXRα, ABCA1, and ABCG1 were detected in macrophages from CGI-58 Tg/ApoE^−/− mice compared to CGI-58 WT/ApoE^−/− counterparts, which were accompanied by elevated macrophage cholesterol efflux toward HDL and Apo A1. Nevertheless, serum levels of TNF-α and IL-6 were reduced by macrophage-specific CGI-58 overexpression. Finally, bone marrow (BM) transplantation experiments further revealed that ApoE^−/− mice reconstituted with Mac-CGI-58 Tg BM cells (ApoE^−/−/Tg-BM chimera) displayed a significant reduction of atherosclerosis lesions compared with control mice reconstituted with Mac-CGI-58 WT BM cells (ApoE^−/−/WT-BM chimera). Collectively, these data strongly suggest that CGI-58 overexpression in macrophages may protect against atherosclerosis development in mice.     

Relation between Delayed Skin Reactivity and Macrophage Migration Inhibition or Lymphocyte Transformation in Tuberculin-Type Hypersensitivity and Jones-Mote Hypersensitivity

Precise time-course studies on delayed skin reaction, lymphocyte transformation and macrophage migration inhibition were carried out from day 3 to 270 and from day 3 to 120, respectively, in guinea pigs immunized with bovine gamma-globulin (BGG) in complete Freund's adjuvant (CFA) and those immunized with BGG in incomplete Freund's adjuvant (IFA). a) Delayed skin reactions could be elicited for a long period of time after immunization with BGG in CFA in the presence of prominent antibody production and were accompanied by induration. b) Delayed reactions could be elicited transiently after immunization with BGG in IFA and were not accompanied by induration. c) At the peak of hypersensitivity, infiltrating cells at the reaction sites were composed largely of mononuclear cells and basophils, respectively, in the animals immunized with BGG in CFA and those immunized with BGG in IFA. d) Uptake of ³H-thymidine by lymphocytes was increased remarkably in the presence of BGG when cells were obtained at early stages after immunization by both methods. e) Macrophage migration inhibition was strongly positive in animals immunized with BGG in CFA but weakly positive in those immunized with BGG in IFA. Increased lymphocyte transformation preceded the appearance of a positive migration inhibition. f) After immunization with BGG in CFA, Jones-Mote hypersensitivity appeared to precede the development of tuberculin-type hypersensitivity.     

Deletion of natriuretic peptide receptor C alleviates adipose tissue inflammation in hypercholesterolemic Apolipoprotein E knockout mice

The inflammation of adipose tissue is one of the most common secondary pathological changes in atherosclerosis, which in turn influences the process of atherosclerosis. Natriuretic peptides have been revealed important effect in regulating adipose metabolism. However, the relationship between natriuretic peptide receptor C and inflammation of adipose tissue in atherosclerosis remains unknown. This study aims to explore the effect natriuretic peptide receptor C exerts on the regulation of the adipose inflammation in atherosclerotic mice induced by western-type diet and its overlying mechanisms. To clarify the importance of NPRC of adipose inflammation in atherosclerotic mice, NPRC expression was measured in mice fed with chow diet and western-type diet for 12 weeks and we found a considerable increase in adipose tissue of atherosclerotic mice. Global NPRC knockout in mice was bred onto ApoE^−/− mice to generate NPRC^−/−ApoE^−/− mice, which displayed remarked increase in browning of white adipose tissue and lipolysis of adipose tissue and decrease in adipose inflammation manifested by decreased macrophage invasion to form less CLS (crown-like structure), reduced oxidative stress and alleviated expression of TNFα, IL-6, IL-1β and MCP1, but increased expression of adiponectin in adipose tissue. Moreover, our study showed that white adipose tissue browning in NPRC^−/−ApoE^−/− atherosclerotic mice was associated with decreased inflammatory response through cAMP/PKA signalling activation. These results identify NPRC as a novel regulator for adipose inflammation in atherosclerotic mice by modulating white adipose tissue browning.     

Hapten-Specific T Cell Response to Azobenzenearsonate-N-Acetyl-L-Tyrosine (ABA-tyr) in Lewis Rats: II. Induction and Suppression of ABA-Specific Helper Cell Activity for Antibody Production

Immunization of Lewis rats with azobenzenearsonate-N-acetyl-l-tyrosine (ABA-tyr) in complete Freund's adjuvant (CFA), produces a hapten-specific helper T cell response measured by an increase in plaque forming cells (PFC) against a different hapten. The response seen is primarily direct (IgM) PFC unless B cells are primed by injection of trinitrophenylated keyhole limpet hemocyanin (TNP-KLH) prior to immunization with ABA-tyr. The response requires both ABA and TNP to be on the same carrier molecule which can be as diverse as bovine serum albumin (BSA), poly l-glutamine-lysine-tyrosine (l-GLT); however, a d-amino acid polypeptide does not work. The in vitro demonstration of such help was successful only with peritoneal exudate lymphocytes, not spleen or lymph node cells. Repeated pretreatment of rats by intraperitoneal injection of ABA-tyr in incomplete Freund's adjuvant (IFA) induced an unresponsiveness for helper activity to subsequent immunization with the same antigen in CFA. Passive transfer of lymphoid cells from spleens and lymph nodes from rats pretreated with ABA-tyr in IFA followed by boosting with ABA-tyr in CFA induced unresponsiveness to subsequent induction of hapten-specific help.     

Interleukin-7, but Not Thymic Stromal Lymphopoietin,Plays a Key Role in the T Cell Response to Influenza A Virus

The immune response to viral infection is ideally rapid and specific, resulting in viral clearance and establishment of immune memory. Some viruses such as HIV can evade such responses leading to chronic infection, while others like Influenza A can elicit a severe inflammatory response with immune-related complications including death. Cytokines play a major role in shaping the appropriate outcomes to infection. While Interleukin-7 (IL-7) has a critical role in T and B cell development, treatment with IL-7 has recently been shown to aid the adaptive T cell response in clearance of chronic viral infection. In contrast, the IL-7-related cytokine thymic stromal lymphopoietin (TSLP) has a limited role in lymphocyte development but is important in the immune response to parasitic worms and allergens. The role for these cytokines in the immune response to an acute viral infection is unclear. IL-7 and TSLP share IL-7Rα as part of their heterodimeric receptors with the gamma common chain (γc) and TSLPR, respectively. We investigated the role of IL-7 and TSLP in the primary immune response to influenza A infection using hypomorphic IL-7Rα (IL-7Rα^449F) and TSLPR^−/− mice. We found that IL-7, but not TSLP, plays an important role in control of influenza A virus. We also showed that IL-7 signaling was necessary for the generation of a robust influenza A-specific CD4 and CD8 T cell response and that this requirement is intrinsic to CD8 T cells. These findings demonstrate a significant role for IL-7 during acute viral infection.     

Angiopoietin-1 aggravates atherosclerosis by inhibiting cholesterol efflux and promoting inflammatory response

ObjectiveAngiopoietin-1 (Ang-1), a secreted protein, mainly regulates angiogenesis. Ang-1 has been shown to promote the development of atherosclerosis, whereas little is known about its effects on lipid metabolism and inflammation in this process.MethodAng-1 was transfected into ApoE^−/− mice via lentiviral vector or incubated with THP-1 derived macrophages. Oil red O and HE staining were performed to measure the size of atherosclerotic plaques in ApoE^−/− mice. Immunofluorescence was employed to show the expression of target proteins in aorta. [³H] labeled cholesterol was performed to examine the efficiency of cholesterol efflux and reverse cholesterol transport (RCT) both in vivo and vitro. Western blot and qPCR were used to quantify target proteins both in vivo and vitro. ELISA detected the levels of pro-inflammatory cytokines in mouse peritoneal macrophage.ResultsOur data showed that Ang-1 augmented atherosclerotic plaques formation and inhibited cholesterol efflux. The binding of Ang-1 to Tie2 resulted in downregulation of LXRα, ABCA1 and ABCG1 expression via inhibiting the translocation of TFE3 into nucleus. In addition, Ang-1 decreased serum HDL-C levels and reduced reverse cholesterol transport (RCT) in ApoE−/− mice. Furthermore, Ang-1 induced lipid accumulation followed by increasing TNF-α, IL-6, IL-1β,and MCP-1 produced by MPMs, as well as inducing M1 phenotype macrophage marker iNOS and CD86 expression in aorta of ApoE^−/− mice.ConclusionAng-1 has an adverse effect on cholesterol efflux by decreasing the expression of ABCA1 and ABCG1 via Tie2/TFE3/LXRα pathway, thereby promoting inflammation and accelerating atherosclerosis progression.     

Serum amyloid A augments the atherogenic effects of cholesteryl ester transfer protein

Serum amyloid A (SAA) is predictive of CVD in humans and causes atherosclerosis in mice. SAA has many proatherogenic effects in vitro. However, HDL, the major carrier of SAA in the circulation, masks these effects. The remodeling of HDL by cholesteryl ester transfer protein (CETP) liberates SAA restoring its proinflammatory activity. Here, we investigated whether deficiency of SAA suppresses the previously described proatherogenic effect of CETP. ApoE^−/− mice and apoE^−/− mice deficient in the three acute-phase isoforms of SAA (SAA1.1, SAA2.1, and SAA3; “apoE^−/− SAA-TKO”) with and without adeno-associated virus-mediated expression of CETP were studied. There was no effect of CETP expression or SAA genotype on plasma lipids or inflammatory markers. Atherosclerotic lesion area in the aortic arch of apoE^−/− mice was 5.9 ± 1.2%; CETP expression significantly increased atherosclerosis in apoE^−/− mice (13.1 ± 2.2%). However, atherosclerotic lesion area in the aortic arch of apoE^−/− SAA-TKO mice (5.1 ± 1.1%) was not significantly increased by CETP expression (6.2 ± 0.9%). The increased atherosclerosis in apoE^−/− mice expressing CETP was associated with markedly increased SAA immunostaining in aortic root sections. Thus, SAA augments the atherogenic effects of CETP, which suggests that inhibiting CETP may be of particular benefit in patients with high SAA.     

CD34+ -derived Langerhans cell-like cells are different from epidermal Langerhans cells in their response to thymic stromal lymphopoietin

Thymic stromal lymphopoietin (TSLP) endows human blood‐derived CD11c⁺ dendritic cells (DCs) and Langerhans cells (LCs) obtained from human epidermis with the capacity to induce pro‐allergic T cells. In this study, we investigated the effect of TSLP on umbilical cord blood CD34⁺‐derived LC‐like cells. These cells are often used as model cells for LCs obtained from epidermis. Under the influence of TSLP, both cell types differed in several ways. As defined by CD83, CD80 and CD86, TSLP did not increase maturation of LC‐like cells when compared with freshly isolated LCs and epidermal émigrés. Differences were also found in the production of chemokine (C‐C motif) ligand (CCL)17. LCs made this chemokine only when primed by TSLP and further stimulated by CD40 ligation. In contrast, LC‐like cells released CCL17 in response to CD40 ligation, irrespective of a prior treatment with TSLP. Moreover, the CCL17 levels secreted by LC‐like cells were at least five times higher than those from migratory LCs. After maturation with a cytokine cocktail consisting of tumour necrosis factor‐α, interleukin (IL)‐1β, IL‐6 and prostaglandin (PG)E₂ LC‐like cells released IL‐12p70 in response to CD40 ligation. Most importantly and in contrast to LC, TSLP‐treated LC‐like cells did not induce a pro‐allergic cytokine pattern in helper T cells. Due to their different cytokine secretion and the different cytokine production they induce in naïve T cells, we conclude that one has to be cautious to take LC‐like cells as a paradigm for ‘real’ LCs from the epidermis.     

Gender differences in the effect of blackberry supplementation in vascular senescence and atherosclerosis in ApoE−/− mice

As the cardiovascular system ages, it becomes more vulnerable to the effects of oxidative stress and inflammation. The aging process, along with external factors such as radiation exposure and lifestyle, induces vascular senescence and accelerates atherosclerotic plaque accumulation. Expression of nicotinamide adenine dinucleotide phosphate oxidase 1 (Nox1), which produces superoxide, is associated with senescence in vascular smooth muscle cells in vitro and atherosclerosis in ApoE^−/− mice in vivo. However, it is unknown whether Nox1 could be down-regulated by nutritional interventions aimed to reduce atherosclerosis. Here we study the effect of blackberry supplementation in Nox1 expression and atherosclerosis. Four-month-old ApoE^−/− male and female mice were fed low-fat, high-fat or high-fat supplemented with 2% freeze-dried blackberry powder diets for 5 weeks. Analysis of the aorta showed that diet supplemented with blackberry significantly decreased plaque accumulation, senescence associated-β-galactosidase and Nox1 expression in the aorta of male but not female mice. The lipid profile was unchanged by blackberry in both female and male animals. Thus, the known role of Nox1 in atherosclerosis suggests that the atheroprotective effect of blackberry is mediated by Nox1 down-regulation in male mice and that Nox1 is regulated in a gender-dependent manner in females.     

Protein deglycase DJ-1 deficiency induces phenotypic switching in vascular smooth muscle cells and exacerbates atherosclerotic plaque instability

Protein deglycase DJ-1 (DJ-1) is a multifunctional protein involved in various biological processes. However, it is unclear whether DJ-1 influences atherosclerosis development and plaque stability. Accordingly, we evaluated the influence of DJ-1 deletion on the progression of atherosclerosis and elucidate the underlying mechanisms. We examine the expression of DJ-1 in atherosclerotic plaques of human and mouse models which showed that DJ-1 expression was significantly decreased in human plaques compared with that in healthy vessels. Consistent with this, the DJ-1 levels were persistently reduced in atherosclerotic lesions of ApoE^−/− mice with the increasing time fed by western diet. Furthermore, exposure of vascular smooth muscle cells (VSMCs) to oxidized low-density lipoprotein down-regulated DJ-1 in vitro. The canonical markers of plaque stability and VSMC phenotypes were evaluated in vivo and in vitro. DJ-1 deficiency in Apoe^−/− mice promoted the progression of atherosclerosis and exaggerated plaque instability. Moreover, isolated VSMCs from Apoe^−/−DJ-1^−/− mice showed lower expression of contractile markers (α-smooth muscle actin and calponin) and higher expression of synthetic indicators (osteopontin, vimentin and tropoelastin) and Kruppel-like factor 4 (KLF4) by comparison with Apoe^−/−DJ-1^+/+ mice. Furthermore, genetic inhibition of KLF4 counteracted the adverse effects of DJ-1 deletion. Therefore, our results showed that DJ-1 deletion caused phenotype switching of VSMCs and exacerbated atherosclerotic plaque instability in a KLF4-dependent manner.     

TSLP receptor is not essential for house dust mite-induced allergic rhinitis in mice

TSLP induces Th2 cytokine production by Th2 cells and various other types of cells, thereby contributing to Th2-type immune responses and development of allergic disorders. We found that house dust mite (HDM) extract induced TSLP production by nasal epithelial cells, suggesting that TSLP may be involved in development of HDM-induced allergic rhinitis (AR). To investigate that possibility in greater detail, wild-type and TSLP receptor-deficient (TSLPR^?/?) mice on the C57BL/6J background were repeatedly treated intranasally with HDM extract. The frequency of sneezing, numbers of eosinophils and goblet cells, thickness of submucosal layers, serum levels of total IgE and HDM-specific IgG1, and levels of IL-4, IL-5 and IL-13 in the culture supernatants of HDM-stimulated LN cells were comparable in the two mouse strains. Those findings indicate that, in mice, TSLPR is not crucial for development of HDM-induced AR.     

Immune Response against Hamster Erythrocytes in the Low-Responder Mouse Strains

Patterns of proliferation of antibody-forming cells after an intravenous immunization with hamster erythrocytes (HRBC) were compared in groups of mice possessing different activities of thymus-derived lymphocytes (T cells). 1) Marked differences in the numbers of hemolysin plaque-forming cells (PFC) after HRBC injection were found among the low- and high-responder normal mice and those pretreated with HRBC in complete Freund's adjuvant (CFA) or incomplete adjuvant (IFA), and they appeared to depend primarily upon the different rates of proliferation of antibody-forming cells rather than on the numbers of antigen-specific lymphocytes initiating the antibody response. 2) The numbers of hemolytic foci were slightly larger in mice with large numbers of PFC (normal SL mice, the pretreated SL and C57BL/6 mice) than in those with small numbers of PFC (normal C57BL/6 mice). The numbers of hemolytic foci increased at almost the same rate from day 2 to day 3 in both groups, while the numbers of PFC increased more efficiently in mice with large numbers of PFC than in those with small numbers of PFC from day 2 to day 3. Individual hemolytic foci appeared to contain larger numbers of PFC in mice with large total numbers of PFC than in those with small total numbers of PFC. 3) The numbers of rosette-forming cells (RFC) were increased by pretreatment with HRBC in CFA and by pretreatment with HRBC in IFA to almost the same extent. Rates of increases in PFC were, however, larger by pretreatment with HRBC in CFA than with HRBC in IFA. These results suggested that the activity of the T cell determined not only the rates of proliferation of antibody-forming cells but also the antibody-producing capacity of each cell.     

The Modulation of Endoplasmic Reticulum Stress by Chemical Chaperone Upregulates Immune Negative Cytokine IL-35 in Apolipoprotein E-Deficient Mice

Interleukin (IL)-35 is a newly identified immune negative molecule which is secreted by CD4⁺Foxp3⁺ T regulatory cells (Tregs) and contributes to their suppressive capacity. Early data have shown that IL-35 inhibits development of several autoimmune diseases. However, the role of IL-35 in atherosclerosis, a lipid-driven chronic inflammatory disease in arterial wall, remains to be investigated. Here, we found that IL-35 was involved in atherosclerosis in apolipoprotein E-deficient (ApoE^−/−) mice. ApoE^−/− mice with established atherosclerotic lesion displayed a lower level of IL-35 compared to age-matched wild type C57BL/6 mice without plaque. However, IL-35 expression increased significantly in ApoE^−/− mice with attenuated plaque. More importantly, we found that modulation of ER stress treated by chemical chaperone, 4-Phenyl butyric acid (PBA) in vivo, mainly upregulated immune negative regulating molecule IL-35, as well as IL-10 and Foxp3, accompanied by increased Tregs. However, no obvious impact on pro-inflammatory molecules such as TNF-α, IFN-γ, IL-17 and IL-23 was observed, which provides new insight into the benefit of ER stress recovery from attenuated plaque. Our results suggest that IL-35 might have a potential value for atherosclerotic therapy.     

Amygdalin mediates relieved atherosclerosis in apolipoprotein E deficient mice through the induction of regulatory T cells

Objective: Regulatory T cells (Tregs) play a critical role in the regulation of T cell-mediated immune responses in atherosclerosis, a chronic autoimmune-like disease. Therefore, in this study, we aimed to investigate the therapeutic effect of amygdalin on atherosclerosis of apolipoprotein E deficient (ApoE^−/−) mice, and to explore its immune regulatory function by stimulation of Tregs. Methods and results: To evaluate the anti-atherosclerotic effect of amygdalin and for in vivo Treg expansion/activation analysis, ApoE^−/− mice received intraperitoneal injections of amygdalin, and this therapy resulted in a comparatively 2-fold decrease in triglyceride (TG), 1.5-fold decrease in total cholesterol (TC) and low density lipoprotein (LDL). By comparing the vessel areas, lumen areas, plaque areas, and aortic plaque coverage percentage, the effects of amygdalin on pre-existing lesions were assessed. Studies on IL-10 and TGF-β indicated that mice treated with amygdalin had increased expression of Treg-related cytokines. Meanwhile, flow cytometry and real-time PCR data showed that mice treated with amygdalin had higher percentage of CD4⁺CD25⁺Foxp3⁺ T cells than untreated mice and increased expression of forkhead box P3 (FOXP3) gene. Conclusion: Our data showed amygdalin could attenuate the development of atherosclerosis by suppressing inflammatory responses and promoting the immunomodulation function of Tregs. The effects of amygdalin ultimately resulted in the enlarged lumen area and the loss of atherosclerotic plaque. All these data indicated the therapeutic potential of amygdalin in preventing and/or treating of atherosclerosis.