Pravastatin Prevents Aortic Atherosclerosis via Modulation of Signal Transduction and Activation of Transcription 3 (STAT3) to Attenuate Interleukin-6 (IL-6) Action in ApoE Knockout Mice

The purpose of this study was to determine whether pravastatin’s prevention of aortic atherosclerosis via attenuation of IL-6 action depends on modulation of STAT3 activity. Male apoE knockout (apoE-/-) mice fed on a diet containing 1.25% cholesterol (wt/wt) were divided into pravastatin group provided with pravastatin (80 mg kg^-1 per day) and atherosclerosis group. After eight weeks, pravastatin significantly prevented atherosclerotic lesion and reduced levels of IL-6 in serum and lesion, and significantly decreased expressions of phosphorylated STAT3 (pSTAT3) and increased suppressor of cytokine signaling 3 (SOCS3) expressions in lesions. Our results suggested that pravastatin’s aortic atherosclerosis preventing action via attenuation of IL-6 action may partially depend on modulation of STAT3 activity.     

Bacteria displaying interleukin-4 mutants stimulate mammalian cells and reflect the biological activities of variant soluble cytokines

We describe a novel procedure that allows the rapid determination of cytokine activity on cells that express their cognate receptor. The four-helix bundle cytokine interleukin-4 (IL-4) was inducibly expressed as a fusion with the E. coli outer-membrane protein intimin, such that IL-4 was presented on the surfaces of the bacteria. Expression and accessibility of the cytokine on the cell exteriors were monitored by Western blotting and fluorescence microscopy, making use of two epitopes flanking the IL-4 component of the fusion protein. To demonstrate the biological activity of the immobilized cytokine, a Ba/F3-derived cell line stably transfected with both the bipartite human IL-4 receptor and an IL-4-specific luciferase reporter gene construct was employed. Bacterial cells displaying interleukin-4 elicited a specific, dose-dependent response in the reporter cells. Two variants of IL-4 with previously characterized (partial) antagonistic properties were also expressed as membrane-bound fusion proteins and were tested for their activity in the immobilized state. In comparison with bacteria displaying wild-type IL-4, E. coli clones presenting variants IL-4 Y124G and Y124D showed diminished or abolished activity, respectively, on murine reporter cells. The relative signaling potencies of the immobilized IL-4 variants thus closely mirror the agonistic properties of the corresponding soluble cytokines. This approach should be generally applicable for the mutational analysis of numerous signal mediators that trigger cellular responses through dimerization of transmembrane receptors.     

Lung Inflammasome Activation in SARS-CoV-2 Post-Mortem Biopsies

The inflammasome complex is a key part of chronic diseases and acute infections, being responsible for cytokine release and cell death mechanism regulation. The SARS-CoV-2 infection is characterized by a dysregulated cytokine release. In this context, the inflammasome complex analysis within SARS-CoV-2 infection may prove beneficial to understand the disease’s mechanisms. Post-mortem minimally invasive autopsies were performed in patients who died from COVID-19 (n = 24), and lung samples were compared to a patient control group (n = 11) and an Influenza A virus H1N1 subtype group from the 2009 pandemics (n = 10). Histological analysis was performed using hematoxylin-eosin staining. Immunohistochemical (IHC) staining was performed using monoclonal antibodies against targets: ACE2, TLR4, NF-κB, NLRP-3 (or NALP), IL-1β, IL-18, ASC, CASP1, CASP9, GSDMD, NOX4, TNF-α. Data obtained from digital analysis underwent appropriate statistical tests. IHC analysis showed biomarkers that indicate inflammasome activation (ACE2; NF-κB; NOX4; ASC) were significantly increased in the COVID-19 group (p < 0.05 for all) and biomarkers that indicate cell pyroptosis and inflammasome derived cytokines such as IL-18 (p < 0.005) and CASP1 were greatly increased (p < 0.0001) even when compared to the H1N1 group. We propose that the SARS-CoV-2 pathogenesis is connected to the inflammasome complex activation. Further studies are still warranted to elucidate the pathophysiology of the disease.     

Dietary Perilla Oil Inhibits Proinflammatory Cytokine Production in the Bronchoalveolar Lavage Fluid of Ovalbumin-Challenged Mice

To evaluate the anti-inflammatory effects of different dietary oils on ovalbumin-sensitized and -challenged mice. Experimental BALB/c mice were fed with different diets containing 5% corn oil [rich in linoleic acid, 18:2n-6 polyunsaturated fatty acids (PUFA), as a control diet], 5% perilla oil (rich in alpha-linolenic acid, 18:3n-3 PUFA) or 5% compound oil containing 50% corn oil and 50% perilla oil, for 5 consecutive weeks. The leukocyte count, inflammatory mediators, and cytokine levels, including proinflammatory and Th1/Th2 cytokines in the bronchoalveolar lavage fluid (BALF) from the mice were determined. The results showed that 5% compound oil administration significantly (P < 0.05) decreased eosinophilic infiltration. Dietary perilla oil could not significantly (P > 0.05) decrease the eosinophil accumulation or the secretions of inflammatory mediators such as prostaglandin E2 (PGE2), histamine, nitric oxide and eotaxin. However, dietary perilla oil significantly (P < 0.05) reduced proinflammatory cytokine (TNF-alpha, IL-1beta and IL-6) and Th1 cytokine (IFN-gamma and IL-2) production. The production of Th2 cytokine IL-10, but not IL-4 and IL-5, was also significantly inhibited by perilla oil administration. The results suggest that dietary perilla oil might alleviate inflammation via decreasing the secretion of pro-inflammatory cytokines in BALF, but failed to regulate the Th1/Th2 balance toward Th1 pole during the Th2-skewed allergic airway inflammation.     

The Effects of Amine-Carboxyborane Related Derivatives on UMR-106 Bone Metabolism

The amine-carboxyboranes and related derivatives have been shown to be potent anti-inflammatory and anti-osteoporosis agents. Their action in part appears to be mediated by the modulation of cytokines, e.g. TNFalpha or IL-1. Previous studies have demonstrated that LPS induced macrophages release of TNFalpha maximally at 60 to 90 min. and IL-1 from 5 to 8 hr. The amine-carboxyboranes reduced significantly the release of these cytokines but also blocked TNFalpha high affinity binding to UMR-106 receptor at 90 min. at 10 muM, and IL-1 high affinity binding at 5 hr. at 12.5 muM. In addition, the agents suppressed IL-8 binding to CHO K1 high affinity receptor at 24 hr. at 50 muM and IL-2 binding to HuT-8 receptors at 25 muM at 90 min. and 5 hr. Correlation of metabolic events associated with osteoporosis showed that at 90 min., when TNFalpha receptor binding was reduced by the agents, calcium uptake into UMR-106 cells was reduced at 10 muM as well as the acid and alkaline phosphatases, and the prostaglandin cyclo-oxygenase activities and adhesion of leukocytes and macrophages to UMR-106 cell monolayers. At 5hr. when the agents reduced IL-1 binding to UMR-106 receptors, calcitonin and 1,25-dihydrovitamin D(3) binding was reduced by the agents as was acid and alkaline phosphatase, and 5'-lipoxygenase activities and white blood cell adhesion. At this time calcium uptake and proline incorporation was increased significantly by the agents. At later times e.g. 18-48 hr. calcium uptake was still increased, and NAG activity was inhibited in the presence of the agents. These effects may be related more to the inhibition of other cytokine receptor binding, e.g. IL-8. Thus, many of the observed metabolic effects of amine-carboxyboranes as antiosteoporosis agents can be correlated with their inhibition of cytokine high affinity binding to target cell receptors.     

Multiplex Analysis of Serum Cytokine Profiles in Systemic Lupus Erythematosus and Multiple Sclerosis

Changes in cytokine profiles and cytokine networks are known to be a hallmark of autoimmune diseases, including systemic lupus erythematosus (SLE) and multiple sclerosis (MS). However, cytokine profiles research studies are usually based on the analysis of a small number of cytokines and give conflicting results. In this work, we analyzed cytokine profiles of 41 analytes in patients with SLE and MS compared with healthy donors using multiplex immunoassay. The SLE group included treated patients, while the MS patients were drug-free. Levels of 11 cytokines, IL-1b, IL-1RA, IL-6, IL-9, IL-10, IL-15, MCP-1/CCL2, Fractalkine/CX3CL1, MIP-1a/CCL3, MIP-1b/CCL4, and TNFa, were increased, but sCD40L, PDGF-AA, and MDC/CCL22 levels were decreased in SLE patients. Thus, changes in the cytokine profile in SLE have been associated with the dysregulation of interleukins, TNF superfamily members, and chemokines. In the case of MS, levels of 10 cytokines, sCD40L, CCL2, CCL3, CCL22, PDGF-AA, PDGF-AB/BB, EGF, IL-8, TGF-a, and VEGF, decreased significantly compared to the control group. Therefore, cytokine network dysregulation in MS is characterized by abnormal levels of growth factors and chemokines. Cross-disorder analysis of cytokine levels in MS and SLE showed significant differences between 22 cytokines. Protein interaction network analysis showed that all significantly altered cytokines in both SLE and MS are functionally interconnected. Thus, MS and SLE may be associated with impaired functional relationships in the cytokine network. A cytokine correlation networks analysis revealed changes in correlation clusters in SLE and MS. These data expand the understanding of abnormal regulatory interactions in cytokine profiles associated with autoimmune diseases.     

Inflammatory Response in COVID-19 Patients Resulting from the Interaction of the Inflammasome and SARS-CoV-2

The outbreak of the coronavirus disease 2019 (COVID-19) began at the end of 2019. COVID-19 is caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and patients with COVID-19 may exhibit poor clinical outcomes. Some patients with severe COVID-19 experience cytokine release syndrome (CRS) or a cytokine storm—elevated levels of hyperactivated immune cells—and circulating pro-inflammatory cytokines, including interleukin (IL)-1β and IL-18. This severe inflammatory response can lead to organ damage/failure and even death. The inflammasome is an intracellular immune complex that is responsible for the secretion of IL-1β and IL-18 in various human diseases. Recently, there has been a growing number of studies revealing a link between the inflammasome and COVID-19. Therefore, this article summarizes the current literature regarding the inflammasome complex and COVID-19.     

Effects of Oral Exposure to Low-Dose Bisphenol S on Allergic Asthma in Mice

Bisphenol S (BPS) is increasingly being used as an alternative for bisphenol A; however, its health effects remain unclear. We investigated the effects of oral exposure to low-dose BPS on allergic asthma. C3H/HeJ male mice were intratracheally administered with allergen (ovalbumin (OVA), 1 μg/animal) every 2 weeks from 6 to 11 weeks old. BPS was ingested by drinking water at doses equivalent to 0.04, 0.4, and 4 μg/kg/day. We then examined pulmonary inflammation, airway hyperresponsiveness, serum OVA-specific immunoglobulin (Ig) levels, Th2 cytokine/chemokine production, and mediastinal lymph node (MLN) cell activities. Compared with OVA alone, moderate-dose BPS (BPS-M) with OVA significantly enhanced pulmonary inflammation, airway hyperresponsiveness, and OVA-specific IgE and IgG1. Furthermore, interleukin (IL)-5, IL-13, IL-33, and CCL11/Eotaxin protein levels in the lungs increased. Conversely, these allergic responses were reduced in the high-dose BPS+OVA group. In MLN cells, BPS-M with OVA increased the total cell count and activated antigen-presenting cells including conventional dendritic cell subset (cDC2). After OVA restimulation, cell proliferation and Th2 cytokine production (IL-4, IL-5, and IL-13) in the culture supernatant also increased. Therefore, oral exposure to low-dose BPS may exacerbate allergic asthmatic responses by enhancing Th2-polarized responses and activating the MLN cells.     

Interleukin-15 Affects Differentiation and Apoptosis in Adipocytes: Implications in Obesity

Interleukin-15 (IL-15) is an anabolic factor for skeletal muscle and several reports have described its important role as a regulator of energy homeostasis. In this study, we analyzed the effects of IL-15 on adipocyte differentiation using the 3T3-L1 preadipose cell line. The data show that IL-15 tends to reduce the rate of adipocyte proliferation, induces apoptosis, and partially stops differentiation. The signaling molecules behind these actions of the cytokine on adipose cells are: p42/p44 MAPK (which seem to be associated with the reduced rate of proliferation induced by the cytokine), STAT5 (which is related to the actions of IL-15 on differentiation), and SAPK/JNK (which are related to the increased apoptosis induced by IL-15). In conclusion, using the 3T3-L1 adipocyte cell line, the results presented here show that IL-15 exerts important effects on differentiation, proliferation and apoptosis. Altogether, the results presented here reinforce the idea that IL-15 is an important mediator that regulates adipose size and, therefore, the role of the cytokine in affecting body weight and obesity deserves additional studies.     

Topical Melatonin Exerts Immunomodulatory Effect and Improves Dermatitis Severity in a Mouse Model of Atopic Dermatitis

Oral melatonin supplement has been shown to improve dermatitis severity in children with AD, but the mechanism of the effect is unclear, and it is uncertain whether melatonin has a direct immunomodulatory effect on the dermatitis. Topical melatonin treatment was applied to DNCB-stimulated Balb/c mice, and gross and pathological skin findings, serum IgE, and cytokine levels in superficial lymph nodes were analyzed. Secretion of chemokines and cell proliferative response after melatonin treatment in human keratinocyte HaCaT cells were also studied. We found that in DNCB-stimulated Balb/c mice, topical melatonin treatment improved gross dermatitis severity, reduced epidermal hyperplasia and lymphocyte infiltration in the skin, and decreased IP-10, CCL27, IL-4, and IL-17 levels in superficial skin-draining lymph nodes. Melatonin also reduced cytokine-induced secretion of AD-related chemokines IP-10 and MCP-1 and decreased IL-4-induced cell proliferation in HaCaT cells. Melatonin seems to have an immunomodulatory effect on AD, with IP-10 as a possible target, and topical melatonin treatment is a potentially useful treatment for patients with AD.     

Tonabersat Inhibits Connexin43 Hemichannel Opening and Inflammasome Activation in an In Vitro Retinal Epithelial Cell Model of Diabetic Retinopathy

This study was undertaken to evaluate the connexin hemichannel blocker tonabersat for the inhibition of inflammasome activation and use as a potential treatment for diabetic retinopathy. Human retinal pigment epithelial cells (ARPE-19) were stimulated with hyperglycemia and the inflammatory cytokines IL-1β and TNFα in order to mimic diabetic retinopathy molecular signs in vitro. Immunohistochemistry was used to evaluate the effect of tonabersat treatment on NLRP3, NLRP1, and cleaved caspase-1 expression and distribution. A Luminex cytokine release assay was performed to determine whether tonabersat affected proinflammatory cytokine release. NLRP1 was not activated in ARPE-19 cells, and IL-18 was not produced under disease conditions. However, NLRP3 and cleaved caspase-1 complex formation increased with hyperglycemia and cytokine challenge but was inhibited by tonabersat treatment. It also prevented the release of proinflammatory cytokines IL-1β, VEGF, and IL-6. Tonabersat therefore has the potential to reduce inflammasome-mediated inflammation in diabetic retinopathy.     

人白细胞介素-18突变体的虚拟筛选及其活性

目的筛选合适的人白细胞介素-18(hIL-18)突变体,并检测其活性。方法运用分子模建工具,模建出IL-18受体及IL-18/IL-18R复合物的分子结构,分别虚拟突变IL-18的4个半胱氨酸为另外19种氨基酸,以野生型IL-18为模板进行同源模建,建立其三维结构模型,计算其IL-18/IL-18R复合物三维结构及分子间作用能变化情况,筛选几种突变方案。运用分子生物学技术构建突变体,表达纯化后进行活性检测。结果根据理论预测情况,筛选了12株突变体。突变的质粒经双酶切及测序鉴定,证明构建正确。突变体蛋白以包涵体形式表达,表达量约占菌体总蛋白的30%,纯化后纯度大于90%。纯化的C38Glu、C127Ser等几株突变体在低浓度时,活性轻微上升,与理论预测结果基本相同。结论已成功构建了多株IL-18的突变体,运用生物信息学方法进行先期筛选有助于加快IL-18的突变研究。     

Blocking the Function of Inflammatory Cytokines and Mediators by Using IL-10 and TGF-β: A Potential Biological Immunotherapy for Intervertebral Disc Degeneration in a Beagle Model

The debilitating effects of lower back pain are a major health issue worldwide. A variety of factors contribute to this, and oftentimes intervertebral disk degeneration (IDD) is an underlying cause of this disorder. Inflammation contributes to IDD, and inflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, play key roles in the pathology of IDD. Therefore, the development of treatments that inhibit the expression and/or effects of TNF-α and IL-1β in IDD patients should be a promising therapeutic approach to consider. This study characterized the potential to suppress inflammatory cytokine production in degenerative intervertebral disc (NP) cells by treatment with IL-10 and TGF-β in a canine model of IDD. IDD was induced surgically in six male beagles, and degenerative NP cells were isolated and cultured for in vitro studies on cytokine production. Cultured degenerative NP cells were divided into four experimental treatment groups: untreated control, IL-10-treated, TGF-β-treated, and IL-10- plus TGF-β-treated cells. Cultured normal NP cells served as a control group. TNF-α expression was evaluated by fluorescence activated cell sorting (FACS) analysis and enzyme-linked immunosorbent assay (ELISA); moreover, ELISA and real-time PCR were also performed to evaluate the effect of IL-10 and TGF-β on NP cell cytokine expression in vitro. Our results demonstrated that IL-10 and TGF-β treatment suppressed the expression of IL-1β and TNF-α and inhibited the development of inflammatory responses. These data suggest that IL-10 and TGF-β should be evaluated as therapeutic approaches for the treatment of lower back pain mediated by IDD.     

Cord Blood T Cells Expressing High and Low PKCζ Levels Develop into Cells with a Propensity to Display Th1 and Th9 Cytokine Profiles,Respectively

Low Protein Kinase C zeta (PKCζ) levels in cord blood T cells (CBTC) have been shown to correlate with the development of allergic sensitization in childhood. However, little is known about the mechanisms responsible. We have examined the relationship between the expression of different levels of PKCζ in CBTC and their development into mature T cell cytokine producers that relate to allergy or anti-allergy promoting cells. Maturation of naïve CBTC was initiated with anti-CD3/-CD28 antibodies and recombinant human interleukin-2 (rhIL-2). To stimulate lymphocyte proliferation and cytokine production the cells were treated with Phytohaemagglutinin (PHA) and Phorbol myristate acetate (PMA). Irrespective of the PKCζ levels expressed, immature CBTC showed no difference in lymphocyte proliferation and the production of T helper 2 (Th2) cytokine interleukin-4 (IL-4) and Th1 cytokine, interferon-gamma (IFN-γ), and influenced neither their maturation from CD45RA⁺ to CD45RO⁺ cells nor cell viability/apoptosis. However, upon maturation the low PKCζ expressing cells produced low levels of the Th1 cytokines, IFN-γ, IL-2 and tumour necrosis factor-alpha (TNF), no changes to levels of the Th2 cytokines, IL-4, IL-5 and IL-13, and an increase in the Th9 cytokine, IL-9. Other cytokines, lymphotoxin-α (LT-α), IL-10, IL-17, IL-21, IL-22 and Transforming growth factor-beta (TGF-β) were not significantly different. The findings support the view that low CBTC PKCζ levels relate to the increased risk of developing allergic diseases.     

Loss of Interleukin-13-Receptor-Alpha-1 Induces Apoptosis and Promotes EMT in Pancreatic Cancer

In search of new therapies for pancreatic cancer, cytokine pathways have attracted increasing interest in recent years. Cytokines play a vital role in the crosstalk between tumour cells and the tumour microenvironment. The related inflammatory cytokines IL-4 and IL-13 can regularly be detected at increased levels in the microenvironment of pancreatic cancer. They share a receptor heterodimer consisting of IL-4Rα and IL-13Rα1. While IL-4Rα induces a more oncogenic phenotype, the role of IL-13Rα1 was yet to be determined. ShRNA-based knockdown of IL-13Rα1 was performed in Capan-1 and MIA PaCa-2. We assessed cell growth and migratory capacities under the influence of IL-13Rα1. Pathway alterations were detected by immunoblot analysis. We now have demonstrated that the loss of IL-13Rα1 induces apoptosis in pancreatic cancer cells. This was associated with an epithelial-to-mesenchymal transition. Loss of IL-13Rα1 also abolished the effects of exogenous IL-4 and IL-13 stimulation. Interestingly, in wild type cells, cytokine stimulation caused a similar increase in migratory capacities as after IL-13Rα1 knockdown. Overall, our results indicate the vital role of IL-13Rα1 in the progression of pancreatic cancer. The differential expression of IL-4Rα and IL-13Rα1 has to be taken into account when considering a cytokine-targeted therapy in pancreatic cancer.