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Background: Pulmonary arterial hypertension (PH) is a progressive disease with limited therapeutic options, ultimately leading to right heart failure and death. Recent findings indicate the role of the Warburg effect (aerobic glycolysis) in the development of PH. However, the effect of the glycolysis inhibitor 3-bromopyruvate (3-BrPA) on the pathogenesis of PH has not been well investigated. This study aimed to determine whether 3-BrPA inhibits PH and its possible mechanism. Methods: PH was induced in adult Sprague-Dawley rats by a single intraperitoneal injection of monocrotaline (MCT). 3-BrPA, or phosphate-buffered saline (PBS) was administered via intraperitoneal injection every other day from the first day of MCT-injection to 4 weeks of follow-up, and indices such as right ventricular systolic pressure (RVSP), right ventricular hypertrophy index (RVHI), pulmonary arteriolar remodeling indicated by percent media thickness (% MT), lactate levels and glucose consumption, were evaluated. Pulmonary arteriolar remodeling and right ventricular hypertrophy were observed in hematoxylin-eosin-stained lung sections. Western blotting, immunohistochemistry, and/or immunofluorescence analyses were used to measure the expression of relevant proteins. A cytochrome C release apoptosis assay and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling staining were used to measure cell apoptosis. Results: MCT-induced PH showed a significant increase in glucose consumption (0 vs. 4 weeks: 0.87 ± 0.23 vs. 2.94 ± 0.47, P = 0.0042) and lactate production (0 vs. 4 weeks: 4.19 ± 0.34 vs. 8.06 ± 0.67, P = 0.0004). Treatment with 3-BrPA resulted in a concomitant reduction in glucose consumption (1.10 ± 0.35 vs. 3.25 ± 0.47, P = 0.0063), lactate production (5.09 ± 0.55 vs. 8.06 ± 0.67, P= 0.0065), MCT-induced increase in RVSP (39.70 ± 2.94 vs. 58.85 ± 2.32, P= 0.0004), pulmonary vascular remodeling (% MT, 43.45% ± 1.41% vs. 63.66% ± 1.78%, P < 0.0001), and right ventricular hypertrophy (RVHI, 38.57% ± 2.69% vs. 62.61% ± 1.57%, P < 0.0001) when compared with those of the PBS-treated group. 3-BrPA, a hexokinase 2 inhibitor, exerted its beneficial effect on PH by decreasing aerobic glycolysis and was also associated with inhibiting the expression of glucose transporter protein-1, inducing apoptosis, and suppressing inflammation. Conclusions: 3-BrPA might have a potential beneficial effect on the PH treatment. Key words: Pulmonary arterial hypertension; Monocrotaline; 3-Bromopyruvate; Aerobic glycolysis

Aberrant RNA splicing in keratinocytes drives inflammatory skin disorders. In the present study, we found that the RNA helicase DDX5 was downregulated in keratinocytes from the inflammatory skin lesions in patients with atopic dermatitis and psoriasis, and that mice with keratinocyte-specific deletion of Ddx5 (Ddx5∆KC) were more susceptible to cutaneous inflammation. Inhibition of DDX5 expression in keratinocytes was induced by the cytokine interleukin (IL)-17D through activation of the CD93–p38 MAPK–AKT–SMAD2/3 signaling pathway and led to pre-messenger RNA splicing events that favored the production of membrane-bound, intact IL-36 receptor (IL-36R) at the expense of soluble IL-36R (sIL-36R) and to the selective amplification of IL-36R-mediated inflammatory responses and cutaneous inflammation. Restoration of sIL-36R in Ddx5∆KC mice with experimental atopic dermatitis or psoriasis suppressed skin inflammation and alleviated the disease phenotypes. These findings indicate that IL-17D modulation of DDX5 expression controls inflammation in keratinocytes during inflammatory skin diseases.

The appropriate inflammatory response is essential for normal wound repair, and skin commensal Staphylococcus epidermidis has been shown to regulate TLR3-mediated inflammatory response to maintain skin homeostasis after injury. However, the underlying mechanism by which S. epidermidis regulates wound-induced inflammation remains largely unexplored. In this study we identified a previously unknown lipopeptide 78 (LP78) from S. epidermidis and showed that LP78 inhibited TLR3-mediated skin inflammation to promote wound healing. Skin injury activated TLR3/NF-κB to promote the interaction of p65 and PPARγ in nuclei and then initiated the inflammatory response in keratinocytes. LP78 activated TLR2-SRC to induce β-catenin phosphorylation at Tyr654. The phospho–β-catenin translocated into nuclei to bind to PPARγ, thus disrupting the interaction between p65 and PPARγ. The disassociation between p65 and PPARγ reduced the expression of TLR3-induced inflammatory cytokines in skin wounds of normal and diabetic mice, which correlated with accelerated wound healing. Our data demonstrate that S. epidermidis–derived LP78 inhibits skin inflammation to promote wound healing and suggest that LP78 might be a potential compound for the treatment of delayed or unhealed wounds.

The elderly population is prone to tendinopathy due to aging-related tendon changes such as cellular senescence and a decreased ability to modulate inflammation. Aging can render tendon stem/progenitor cells (TSCs) into premature senescence. We investigated the effects of rapamycin, a specific mTOR inhibitor, on the senescence of TSCs. We first showed that after treatment with bleomycin in vitro, rat patellar TSCs (PTSCs) underwent senescence, characterized by morphological alterations, induction of senescence-associated β-galactosidase (SA-β-gal) activity, and an increase in p53, p21, and p62 protein expression. Senescence of PTSCs was also characterized by the elevated expression of MMP-13 and TNF-α genes, both of which are molecular hallmarks of chronic tendinopathy. We then showed that rapamycin treatment was able to reverse the above senescent phenotypes and increase autophagy in the senescent PTSCs. The activation of autophagy and senescence rescue was, at least partly, due to the translocation of HMGB1 from the nucleus to the cytosol that functions as an autophagy promoter. By reducing TSC senescence, rapamycin may be used as a therapeutic to inhibit tendinopathy development in the aging population by promoting autophagy.

High mobility group box 1 (HMGB1) is a nuclear protein that is released on injury triggers inflammation. This study aims to elucidate the effects of salidroside on diabetes-induced liver inflammation. The levels of glucose, inflammatory cytokines and hepatic functional parameters in serum and liver of type 2 diabetic db/db mice were examined. Immunohistochemistry, immunofluorescence and western blot tests were performed to determine the mechanisms underlying the action. Palmitic acid (PA) or HMGB1-stimulated was adopted as an in vitro cell model. Salidroside treatment improved glucose tolerance, lipid profiles while decreased the production of inflammatory cytokines. It also reduced the levels of serum biochemical markers. In addition, salidroside inhibited HMGB1 signaling pathway in db/db mice. In the salidroside treatment significantly inhibited PA or HMGB1 induced inflammatory signaling pathway, too. HMGB1 inhibitors and HMGB1 knockdown both hindered PA-induced HMGB1 signaling pathway, showing the same effect as salidroside. Salidroside treatment significantly alleviates insulin resistance, hyperglycemia and hepatic inflammation in db/db mice, and also showed beneficial to PA-stimulated. Salidroside proves to control hyperglycemia and hepatic inflammation via inhibiting HMGB1/RAGE/NF-κB and HMGB1/TLR4/NLRP3 signaling pathways.

Background and Purpose: High mobility group box 1 (HMGB1) is a nuclear protein that is released on injury triggers inflammation. This study aims to elucidate the effects of salidroside on diabetes-induced liver inflammation. Experimental Approach: The levels of glucose, inflammatory cytokines and hepatic functional parameters in serum and liver of type 2 diabetic db/db mice were examined. Immunohistochemistry, immunofluorescence and western blot tests were performed to determine the mechanisms underlying the action. Palmitic acid (PA) or HMGB1–stimulated was adopted as an in vitro cell model. Key Results: Salidroside treatment improved glucose tolerance, lipid profiles while decreased the production of inflammatory cytokines. It also reduced the levels of serum biochemical markers. In addition, salidroside inhibited HMGB1 signaling pathway in db/db mice. In the salidroside treatment significantly inhibited PA or HMGB1 induced inflammatory signaling pathway, too. HMGB1 inhibitors and HMGB1 knockdown both hindered PA-induced HMGB1 signaling pathway, showing the same effect as salidroside. Conclusion: Salidroside treatment significantly alleviates insulin resistance, hyperglycemia and hepatic inflammation in db/db mice, and also showed beneficial to PA-stimulated. Salidroside proves to control hyperglycemia and hepatic inflammation via inhibiting HMGB1/RAGE/NF-κB and HMGB1/TLR4/NLRP3 signaling pathways. Funding Statement: This research was supported by National Natural Science Foundation of China (81400800). Declaration of Interests: The authors declare that they have no conflict of interest Ethics Approval Statement: All animal experiments were conducted in accordance with animal ethics of Zhengzhou University.

IL-36 family members are highly expressed in hyperproliferative keratinocytes and play an important role in the pathogenesis of skin diseases such as psoriasis. However, whether and how IL-36 cytokines are induced to promote wound healing remains unknown. Here we showed that skin injury increased the expression of IL-36γ to promote wound healing. Mechanistically, the expression of IL-36γ was induced by RNAs from damaged cells via the activation of toll-like receptor 3 (TLR3) and TIR-domain-containing adapter-inducing IFN-β (TRIF) followed by the induction of a zinc finger protein SLUG to abrogate the inhibitory effect of vitamin D receptor (VDR) on the promoter of IL-36γ gene. IL-36γ acted back on keratinocytes to induce REG3A, which regulated keratinocyte proliferation and differentiation, thus promoting wound re-epithelialization. These observations show that skin injury increases IL-36γ via the activation of TLR3-SLUG-VDR axis and that IL-36γ induces REG3A to promote wound healing. These findings also provide insights into pathways contributing to wound repair.

Ethnopharmacological relevance Penthorum chinense Pursh is used for promoting diuresis and alleviating “heat”-associated disorders, which were considered to be related to diabetic in Traditional Chinese Medicine (TCM). Aims of this study Here, we aimed to evaluate the ability and underlying mechanism of the ethyl acetate fraction of Penthorum chinense Pursh stems (PSE) to inhibit vascular inflammation in high glucose (HG)-induced human umbilical vein endothelial cells (HUVEC cells). Materials and methods HUVEC cells were pre-treated with PSE following HG treatment. The cell viability, mitochondrial membrane potential (MMP), lactate dehydrogenase (LDH) levels, reactive oxygen species (ROS) generation were analyzed. Inflammatory, and antioxidant,-related proteins were analyzed using western blotting. Molecular docking and drug affinity targeting experiments (DARTS) were utilized to analyze and verify the binding of the Keap1 protein and polyphenols of PSE. Results HG can significantly increase the activity of lactic dehydrogenase (LDH), destroy the mitochondrial membrane potential (MMP), and promote the generation of reactive oxygen species (ROS), while PSE treatment reversed these changes. Mechanistically, PSE inhibited NF-κB and inflammatory cytokines activation induced by HG through activating the expression of Nrf2 and its downstream antioxidant proteins Heme oxygenase-1 (HO-1), NAD (P)H Quinone Dehydrogenase 1 (NQO1), Glutamate cysteine ligase catalytic subunit (GCLC), Glutamate-cysteine ligase modifier (GCLM). Further study indicated that PSE activated Nrf2 antioxidant pathway mainly by the binding of primary polyphenols from PSE and the Keap1 protein. Conclusion Taken together, the present data highlight the health benefits of polyphenols from Penthorum chinense Pursh. regarding diabetes, proving it to be an important source of health care products. Besides, binding of the Keap1 protein may be an effective strategy to activate Nrf2 antioxidant pathway and prevent diabetes.

Objective Inflammation is closely linked to pulmonary arterial hypertension (PAH). Salusin-β, a bioactive peptide, has been reported to participate in vascular inflammation. We therefore hypothesized that salusin-β contributes to monocrotaline (MCT)-induced PAH in rats. Methods Male Sprague-Dawley rats were treated with MCT (60 mg kg −1 , single intraperitoneal injection). Salusin-β expression in the lungs of the MCT-treated rats was evaluated using immunofluorescence staining, western blot, and real-time PCR. For salusin-β blockade assay, rats injected with MCT were given a chronic infusion of anti-salusin-β immunoglobulin G (IgG) (salusin-β blocker, 1.0 μg kg −1 h −1 ) or isotype-matched control IgG. Four weeks after MCT+anti-salusin-β treatment, the effects of salusin-β blockade were determined using hemodynamics, western blot, real-time PCR, and immunohistochemical detection. The effect of salusin-β on human pulmonary arterial endothelial cell (HPAEC) function was detected by adhesion and tube formation experiments in vitro. Results Salusin-β expression was significantly increased in the lungs of the MCT-treated rats, and immunofluorescence results showed that salusin-β was predominantly expressed in pulmonary macrophages and vascular endothelial cells. Salusin-β blockade significantly ameliorated PAH by acting against pulmonary vascular remodeling, decreasing macrophage infiltration, and reducing pro-inflammatory cytokine expression and nuclear factor-kappa B (NF-κB) activity in the lungs of the MCT-treated rats. In addition, salusin-β could induce cell adhesion and accelerate angiogenesis by activating the NF-κB pathway and promoting pro-inflammatory cytokine expression in the cultured HPAECs. This effect was suppressed by addition of the NF-κB inhibitor, N-acetyl-L-cysteine. Conclusions Salusin-β plays a crucial role in the development of MCT-induced PAH models.

Objective To observe the expression of Notch2, NLR family pyrin domain containing 3 (NLRP3) in the renal tissue of rats with diabetes mellitus (DM), and the effects of alpha-lipoamide (ALM) on the expression of Notch2, Toll-like receptor 4 (TLR4), NLRP3 and collagen, to explore the possible protective mechanism of ALM against diabetic renal inflammation and renal fibrosis. Methods The DM rat models were induced by the injection of streptozotocin (STZ) and divided into DM group and ALM group. Meanwhile, normal control (NC) group was set up. There were 8 rats in each group. Two weeks after the successful establishment of DM model, ALM [150 mg/(kg.d)] was given intragastrically to the rats in the ALM group, and the rats were sacrificed 6 weeks later. The morphologic changes of renal tissues were observed by HE and Masson staining. The expression and localization of Notch2, TLR4 and NLRP3 in the renal tissues were detected by immunohistochemical staining. The protein levels of Notch2, TLR4, NLRP3 and collagen 4 (Col4) were determined by Western blot analysis. The levels of interleukin 6 (IL-6) and tumor necrosis factor (TNF-α) in the renal tissue homogenates were measured by ELISA. Spearman rank correlation test was used to analyze the correlation between Notch2, TLR4 and NLRP3 protein expression. Results Compared with the NC group, the levels of blood glucose, 24-hour urine protein, kidney index, total cholesterol and triglyceride in the DM group significantly increased, while compared with the DM group, those in the ALM group were significantly reduced, but there was no significant change in blood glucose. Compared with the NC group, the protein levels of Notch2, TLR4, NLRP3 and Col4 in the renal tissues of the DM group increased. As same as the levels of Notch2, TLR4, NLRP3 and Col4 in the ALM group, the levels of IL-6 and TNF-α in the renal homogenates of the ALM group were significantly lower than those of the DM group. Correlation analysis showed that there was a significant positive correlation between the expressions of Notch2 and TLR4 in the DM group and ALM group, and the expression of Notch2 and NLRP3 were also significantly positively correlated. Conclusion ALM alleviates the renal inflammation and Col4 production in diabetic rats, which is related to the Notch2-induced inhibition of TLR4 and NLRP3 activation.

Coxsackievirus group B (CVB) is considered as one of the most common pathogens of human viral myocarditis. CVB-induced myocarditis is mainly characterized by the persistence of the virus infection and immune-mediated inflammatory injury. Costimulatory signals are crucial for the activation of adaptive immunity. Our data reveal that the CVB type 3 (CVB3) infection altered the expression profile of costimulatory molecules in host cells. CVB3 infection caused the decrease of PD-1 ligand expression, partially due to the cleavage of AU-rich element binding protein AUF1 by the viral protease 3Cpro, leading to the exacerbated inflammatory injury of the myocardium. Moreover, systemic PD-L1 treatment, which augmented the apoptosis of proliferating lymphocytes, alleviated myocardial inflammatory injury. Our findings suggest that PD1-pathway can be a potential immunologic therapeutic target for CVB-induced myocarditis.

T helper 17 (TH17) cells and interleukin-17A (IL-17A) produced by them are critical in autoinflammatory diseases, such as psoriasis. IL-17A has been shown to signal through IL-17 receptor A/IL-17 receptor C (IL-17RA/IL-17RC) complex to drive inflammatory responses. However, in a psoriasis model, we found that Il17rc deficiency did not completely ameliorate the disease, suggesting another receptor. In search for another IL-17A-interacting receptor, we found that IL-17RD directly bound IL-17A but not IL-17F or IL-17A/F heterodimer and formed a heterodimer with IL-17RA. IL-17A-, but not IL-17F- or IL-17A/F-, mediated gene expression was defective in Il17rd-deficient keratinocytes. Il17rd deficiency in nonhemopoietic cells attenuated imiquimod-induced psoriasis-like skin inflammation. Although IL-17RC and IL-17RD differentially activated IL-17A-dependent signaling and gene expression, their compound mutation led to complete deficits in keratinocytes. IL-23 was found induced by IL-17A in keratinocytes, dependent on both IL-17RC and IL-17RD, suggesting feed-forward regulation of IL-23/IL-17 axis in psoriasis. Together, IL-17RD constitutes a second functional receptor for IL-17A and, together with IL-17RC, mediates the proinflammatory gene expression downstream of IL-17A.

Background During myocardial ischemia/reperfusion ( MI /R) injury, there is extensive release of immunogenic metabolites that activate cells of the innate immune system. These include ATP and AMP , which upregulate chemotaxis, migration, and effector function of early infiltrating inflammatory cells. These cells subsequently drive further tissue devitalization. Mesenchymal stromal cells ( MSC s) are a potential treatment modality for MI /R because of their powerful anti‐inflammatory capabilities; however, the manner in which they regulate the acute inflammatory milieu requires further elucidation. CD 73, an ecto‐5′‐nucleotidase, may be critical in regulating inflammation by converting pro‐inflammatory AMP to anti‐inflammatory adenosine. We hypothesized that MSC ‐mediated conversion of AMP into adenosine reduces inflammation in early MI /R, favoring a micro‐environment that attenuates excessive innate immune cell activation and facilitates earlier cardiac recovery. Methods and Results Adult rats were subjected to 30 minutes of MI /R injury. MSC s were encapsulated within a hydrogel vehicle and implanted onto the myocardium. A subset of MSC s were pretreated with the CD 73 inhibitor, α,β‐methylene adenosine diphosphate, before implantation. Using liquid chromatography/mass spectrometry, we found that MSC s increase myocardial adenosine availability following injury via CD 73 activity. MSC s also reduce innate immune cell infiltration as measured by flow cytometry, and hydrogen peroxide formation as measured by Amplex Red assay. These effects were dependent on MSC ‐mediated CD 73 activity. Finally, through echocardiography we found that CD 73 activity on MSC s was critical to optimal protection of cardiac function following MI /R injury. Conclusions MSC ‐mediated conversion of AMP to adenosine by CD 73 exerts a powerful anti‐inflammatory effect critical for cardiac recovery following MI /R injury.

Toll-like receptors (TLRs) are transmembrane pattern-recognition receptors that initiate signals in response to diverse pathogen-associated molecular patterns. Several groups have recently reported a role for TLR2 and TLR4 in ischemic stroke-induced brain injury. However, relatively little is known about the role of TLR8 in ischemic stroke. Here we provide the first evidence that TLR8 activation plays a detrimental role in stroke outcome by promoting neuronal apoptosis and T cell-mediated post-stroke inflammation. TLR8 is expressed in cerebral cortical neurons, where its levels and downstream signaling via JNK are increased in response to oxygen glucose deprivation (OGD). Treatment with a TLR8 agonist activated pro-apoptotic JNK and increased neuronal cell death during OGD. Furthermore, selective knockdown of TLR8 using siRNA protected SH-SY5Y cells following OGD, and TLR8 agonist administration in vivo increased mortality, neurological deficit and T cell infiltration following stroke. Taken together, our findings indicate a detrimental role for neuronal TLR8 signaling in the triggering of post-stroke inflammation and neuronal death.

Dysregulated inflammatory responses are known to impair wound healing in diabetes, but the underlying mechanisms are poorly understood. Here we show that the antimicrobial protein REG3A controls TLR3-mediated inflammation after skin injury. This control is mediated by REG3A-induced SHP-1 protein, and acts selectively on TLR3-activated JNK2. In diabetic mouse skin, hyperglycaemia inhibits the expression of IL-17-induced IL-33 via glucose glycation. The decrease in cutaneous IL-33 reduces REG3A expression in epidermal keratinocytes. The reduction in REG3A is associated with lower levels of SHP-1, which normally inhibits TLR3-induced JNK2 phosphorylation, thereby increasing inflammation in skin wounds. To our knowledge, these findings show for the first time that REG3A can modulate specific cutaneous inflammatory responses and that the decrease in cutaneous REG3A exacerbates inflammation in diabetic skin wounds., Patients with diabetes often have delayed wound healing, associated with excessive inflammation. Here the authors report that REG3A inhibits TLR3-driven inflammation in skin wounds, and show that REG3A is reduced in models of diabetes, which exacerbates inflammation in diabetic wounds.

Sepsis is a devastating and complex syndrome and continues to be a major cause of morbidity and mortality among critically ill patients at the surgical intensive care unit setting in the United States. The occurrence of sepsis and septic shock has increased significantly over the past two decades. Despite of highly dedicated basic research and numerous clinical trials, remarkable progress has not been made in the development of novel and effective therapeutics. The sepsis-induced physiologic derangements are due largely to the host responses to the invading microorganism in contrast to the direct effects of the microorganism itself. Sepsis, the systemic inflammatory response to infection, is marked by dysregulated production of pro-inflammatory cytokines. Although pro-inflammatory cytokine production is normally indispensable to protect against pathogens and promote tissue repair, the dysregulated and prolonged production of these cytokines can trigger a systemic inflammatory cascade mediated by chemokines, vasoactive amines, the complement and coagulation system, and reactive oxygen species (ROS), amongst others. These mediators collectively lead to multiple organ failure, and ultimately to death. In this regard, the role of inflammation in the pathophysiology of sepsis, although still incompletely understood, is clearly critical. Recent findings resulting from vigorous investigations have contributed to delineate various novel directions of sepsis therapeutics. Among these, this review article is focused on new promising mechanisms and concepts that could have a key role in anti-inflammatory strategies against sepsis, including 1) "inflammasome": a multiprotein complex that activates caspase-1; 2) "the cholinergic anti-inflammatory pathway": the efferent arm of the vagus nerve-mediated, brain-to-immune reflex; 3) "stem cells": unspecialized and undifferentiated precursor cells with the capacity for self-renewal and potential to change into cells of multiple lineages; 4) "milk fat globule-EGF factor VIII (MFG-E8)": a bridging molecule between apoptotic cells and phagocytes, which promotes phagocytosis of apoptotic cells.

In the current study, we analyzed the functions and mechanisms of Bletilla striata polysaccharide b (BSPb) against Angiotensin II (Ang II)-induced oxidative stress and inflammation in human mesangial cells (HMCs). It was found that BSPb could inhibit generation of Ang II-induced reactive oxygen species (ROS) and activation of proinflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) in a dose-dependent manner. Further studies revealed that BSPb effectively blocked upregulation of NADPH oxidase 4 (NOX4). Moreover, knockdown of NOX4 significantly impaired the anti-oxidative function of BSPb. In addition, BSPb decreased overexpression of Toll-like receptor 2 (TLR2) induced by Ang II. Blocking TLR2 expression impaired the anti-inflammatory effects of BSPb. In conclusion, BSPb was found to possess anti-oxidative stress and anti-inflammatory functions against Ang II-induced ROS generation and proinflammatory cytokines activation. The NOX4 and TLR2 pathways played important roles in the biological effects mediated by BSPb.

Adipocyte fatty acid-binding protein (A-FABP) plays an important role in fatty acid-mediated processes and related metabolic and inflammatory responses. In this study, we prepared a novel monoclonal antibody against A-FABP, designated 2E4. Our data showed that 2E4 specifically binded to the recombinant A-FABP and native A-FABP of mice adipose tissue. Furthermore, we investigated the effect of 2E4 on metabolic and inflammatory responses in C57BL/6J obese mice fed on a high fat diet. 2E4 administration improved glucose response in high-fat-diet induced obese mice. The 2E4 treated groups exhibited lower free fatty acids, cholesterol, and triglycerides in a concentration-dependent manner. These changes were accompanied by down-regulated expression of pro-inflammatory cytokines in adipose tissue, including tumor necrosis factor α, monocyte chemotactic protein-1, and interleukin-6. Meanwhile, our data demonstrated that 2E4 significantly decreased the mRNA and protein levels of A-FABP in adipose tissue of mice. Further experiments showed that 2E4 notably suppressed the phosphorylation of IκBα and jun-N-terminal kinase through toll-like receptor 4 signaling pathway. Taken together, 2E4 is an effective monoclonal antibody against A-FABP, which attenuated the inflammatory responses induced in the high-fat-diet mice. These findings may provide scientific insight into the treatment of chronic low-grade inflammation in obesity.

Mineralocorticoid receptor (MR) blockade has been shown to suppress cardiac hypertrophy and remodeling in animal models of pressure overload (POL). This study aims to determine whether MR deficiency in myeloid cells modulates aortic constriction-induced cardiovascular injuries. Myeloid MR knockout (MMRKO) mice and littermate control mice were subjected to abdominal aortic constriction (AAC) or sham operation. We found that AAC-induced cardiac hypertrophy and fibrosis were significantly attenuated in MMRKO mice. Expression of genes important in generating reactive oxygen species was decreased in MMRKO mice, while that of manganese superoxide dismutase increased. Furthermore, expression of genes important in cardiac metabolism was increased in MMRKO hearts. Macrophage infiltration in the heart was inhibited and expression of inflammatory genes was decreased in MMRKO mice. In addition, aortic fibrosis and inflammation were attenuated in MMRKO mice. Taken together, our data indicated that MR deficiency in myeloid cells effectively attenuated aortic constriction-induced cardiac hypertrophy and fibrosis, as well as aortic fibrosis and inflammation.

Background— Myocardial reperfusion after ischemia (I/R), although an effective approach in rescuing the ischemic myocardium, can itself trigger several adverse effects including aberrant remodeling of the myocardium and its extracellular matrix. Tissue inhibitor of metalloproteinases (TIMPs) protect the extracellular matrix against excess degradation by matrix metalloproteinases (MMPs). TIMP4 levels are reduced in myocardial infarction; however, its causal role in progression of post-I/R injury has not been explored. Methods and Results— In vivo I/R (20-minute ischemia, 1-week reperfusion) resulted in more severe systolic and diastolic dysfunction in TIMP4 −/− mice with enhanced inflammation, oxidative stress (1 day post-I/R), hypertrophy, and interstitial fibrosis (1 week). After an initial increase in TIMP4 (1 day post-I/R), TIMP4 mRNA and protein decreased in the ischemic myocardium from wild-type mice by 1 week post-I/R and in tissue samples from patients with myocardial infarction, which correlated with enhanced activity of membrane-bound MMP, membrane-type 1 MMP. By 4 weeks post-I/R, wild-type mice showed no cardiac dysfunction, elevated TIMP4 levels (to baseline), and normalized membrane-type 1 MMP activity. TIMP4-deficient mice, however, showed exacerbated diastolic dysfunction, sustained elevation of membrane-type 1 MMP activity, and worsened myocardial hypertrophy and fibrosis. Ex vivo I/R (20- or 30-minute ischemia, 45-minute reperfusion) resulted in comparable cardiac dysfunction in wild-type and TIMP4 −/− mice. Conclusions— TIMP4 is essential for recovery from myocardial I/R in vivo, primarily because of its membrane-type 1 MMP inhibitory function. TIMP4 deficiency does not increase susceptibility to ex vivo I/R injury. Replenishment of myocardial TIMP4 could serve as an effective therapy in post-I/R recovery for patients with reduced TIMP4.

Angiotensin-converting enzyme 2 (ACE2) is a monocarboxypeptidase capable of metabolizing angiotensin (Ang) II into Ang 1 to 7. We hypothesized that ACE2 is a negative regulator of Ang II signaling and its adverse effects on the kidneys. Ang II infusion (1.5 mg/kg −1 /d −1 ) for 4 days resulted in higher renal Ang II levels and increased nicotinamide adenine dinucleotide phosphate oxidase activity in ACE2 knockout ( Ace2 −/y ) mice compared to wild-type mice. Expression of proinflammatory cytokines, interleukin-1β and chemokine (C-C motif) ligand 5, were increased in association with greater activation of extracellular-regulated kinase ½ and increase of protein kinase C-α levels. These changes were associated with increased expression of fibrosis-associated genes (α-smooth muscle actin, transforming growth factor-β, procollagen type Iα1) and increased protein levels of collagen I with histological evidence of increased tubulointerstitial fibrosis. Ang II-infused wild-type mice were then treated with recombinant human ACE2 (2 mg/kg −1 /d −1 , intraperitoneal). Daily treatment with recombinant human ACE2 reduced Ang II-induced pressor response and normalized renal Ang II levels and oxidative stress. These changes were associated with a suppression of Ang II–mediated activation of extracellular-regulated kinase ½ and protein kinase C pathway and Ang II–mediated renal fibrosis and T-lymphocyte-mediated inflammation. We conclude that loss of ACE2 enhances renal Ang II levels and Ang II-induced renal oxidative stress, resulting in greater renal injury, whereas recombinant human ACE2 prevents Ang II-induced hypertension, renal oxidative stress, and tubulointerstitial fibrosis. ACE2 is an important negative regulator of Ang II-induced renal disease and enhancing ACE2 action may have therapeutic potential for patients with kidney disease.

Background Asthma is a complex disorder of the immune system caused by a combination of genetic predisposition with environmental exposures. The environmental factors play a predominant role in the etiology of asthma. It is hypothesized that epigenetic changes in miRNAs play a critical role in pathogenesis of asthma as an interface between genetic makeup and environmental exposures. (Wang, Jia-wang; Li, Kunyu; Hellermann, Gary; Lockey, Richard F.; Mohapatra, Subhra; and Mohapatra, Shyam. Regulating the Regulators: microRNA and Asthma. World Allergy Organization Journal. June 2011, Volume 4, Issue 6). Methods In the present study, we used miRNA array profiling in a mouse model of ovalbumin-induced asthma to identify differentially regulated miRNAs and characterized miR-150 in terms of cellular and humoral involvement and analysis of lung inflammation markers. Results We found that miR-150 was downregulated in CD4 T lymphocytes during asthmatic inflammation and Th1 and Th2 induction. Over-expression of miR-150 delivered by chitosan nanoparticles inhibited lung inflammation and decreased Th1 and Th2 cytokine levels. miR-150 suppressed Akt3, Cbl1 and Elk1 oncogenes, which are involved in inflammation and cytokine production. Transgenic mice overexpressing miR-150 are resistant to asthma induction, demonstrated by reduced AHR and cytokine inflammation production. Conclusions These results suggest that deregulation of miRNAs may be involved in the pathogenesis of asthma and miR-150 may suppress inflammation in asthma by inhibiting cytokine production by downregulating critical genes such as Akt, Elk1 and Cbl1. miR-150 may be an attractive candidate for asthma gene therapy.

Background Atrial natriuretic peptide (ANP) is an important endogenous hormone that controls inflammation and immunity by acting on dendritic cells (DCs); however, the mechanism remains unclear. Objective We analyzed the downstream signaling events resulting from the binding of ANP to its receptor, NPRA, and sought to determine what aspects of this signaling modulate DC function. Methods We utilized the inhibitory peptide, NP73-102, to block NPRA signaling in human monocyte-derived DCs (hmDCs) and examined the effect on DC maturation and induced immune responses. The potential downstream molecules and interactions among these molecules involved in NPRA signaling were identified by immunoprecipitation and immunoblotting. Changes in T cell phenotype and function were determined by flow cytometry and BrdU proliferation ELISA. To determine if adoptively transferred DCs could alter the in vivo immune response, bone marrow-derived DCs from wild-type C57BL/6 mice were incubated with ovalbumin (OVA) and injected i.v. into C57BL/6 NPRA-/- knockout mice sensitized and challenged with OVA. Lung sections were stained and examined for inflammation and cytokines were measured in bronchoalveolar lavage fluid collected from parallel groups of mice. Results Inhibition of NPRA signaling in DCs primes them to induce regulatory T cells. Adoptive transfer of wild type DCs into NPRA-/- mice reverses the attenuation of lung inflammation seen in the NPRA-knockout model. NPRA is associated with TLR-2, SOCS3 and STAT3, and inhibiting NPRA alters expression of IL-6, IL-10 and TGF-β, but not IL-12. Conclusions Modulation of NPRA signaling in DCs leads to immune tolerance and TLR2 and SOCS3 are involved in this induction.