Dietary Vitamin D3 Restriction Exacerbates Disease Pathophysiology in the Spinal Cord of the G93A Mouse Model of Amyotrophic Lateral Sclerosis

BackgroundDietary vitamin D₃ (D₃) restriction reduces paw grip endurance and motor performance in G93A mice, and increases inflammation and apoptosis in the quadríceps of females. ALS, a neuromuscular disease, causes progressive degeneration of motor neurons in the brain and spinal cord.ObjectiveWe analyzed the spinal cords of G93A mice following dietary D₃ restriction at 2.5% the adequate intake (AI) for oxidative damage (4-HNE, 3-NY), antioxidant enzymes (SOD2, catalase, GPx1), inflammation (TNF-α, IL-6, IL-10), apoptosis (bax/bcl-2 ratio, cleaved/pro-caspase 3 ratio), neurotrophic factor (GDNF) and neuron count (ChAT, SMI-36/SMI-32 ratio).MethodsBeginning at age 25 d, 42 G93A mice were provided food ad libitum with either adequate (AI;1 IU D₃/g feed; 12 M, 11 F) or deficient (DEF; 0.025 IU D₃/g feed; 10 M, 9 F) D₃. At age 113 d, the spinal cords were analyzed for protein content. Differences were considered significant at P ≤ 0.10, since this was a pilot study.ResultsDEF mice had 16% higher 4-HNE (P = 0.056), 12% higher GPx1 (P = 0.057) and 23% higher Bax/Bcl2 ratio (P = 0.076) vs. AI. DEF females had 29% higher GPx1 (P = 0.001) and 22% higher IL-6 (P = 0.077) vs. AI females. DEF males had 23% higher 4-HNE (P = 0.066) and 18% lower SOD2 (P = 0.034) vs. AI males. DEF males had 27% lower SOD2 (P = 0.004), 17% lower GPx1 (P = 0.070), 29% lower IL-6 (P = 0.023) and 22% lower ChAT (P = 0.082) vs. DEF females.ConclusionD₃ deficiency exacerbates disease pathophysiology in the spinal cord of G93A mice, the exact mechanisms are sex-specific. This is in accord with our previous results in the quadriceps, as well as functional and disease outcomes.     

Effects of the Commercial Flame Retardant Mixture DE-71 on Cytokine Production by Human Immune Cells

IntroductionAlthough production of polybrominated diphenyl ethers (PBDEs) is now banned, release from existing products will continue for many years. The PBDEs are assumed to be neurotoxic and toxic to endocrine organs at low concentrations. Their effect on the immune system has not been investigated thoroughly. We aimed to investigate the influence of DE-71 on cytokine production by peripheral blood mononuclear cells (PBMCs) stimulated with Escherichia Coli lipopolysaccharide (LPS) or phytohaemagglutinin-L (PHA-L).ResultsAt non-cytotoxic concentrations (0.01–10 μg/mL), DE-71 significantly enhanced secretion of IL-1β, IL-6, CXCL8, IL-10, and TNF-α (p<0.001–0.019; n = 6) from LPS-stimulated PBMCs. IFN-γ, TNF-α, IL-17A, and IL-17F (p = <0.001–0.043; n = 6) secretion were enhanced from PHA-L-stimulated PBMCs as well. Secretion of IL-1β, IL-2, IL-10, IL-8 and IL-6 was not significantly affected by DE-71.ConclusionsWe demonstrate an enhancing effect of DE-71 on cytokine production by normal human PBMCs stimulated with LPS or PHA-L ex vivo.     

Reactivation of Herpes Simplex Virus Type 1 in the Mouse Trigeminal Ganglion: an In Vivo Study of Virus Antigen and Cytokines

Reactivation of herpes simplex virus type 1 (HSV-1) in the trigeminal ganglion (TG) was induced by UV irradiation of the corneas of latently infected mice. Immunocytochemistry was used to monitor the dynamics of cytokine (interleukin-2 [IL-2], IL-4, IL-6, IL-10, gamma interferon [IFN-γ], and tumor necrosis factor alpha [TNF-α]) and viral antigen production in the TG and the adjacent central nervous system on days 1 to 4, 6, 7, and 10 after irradiation. UV irradiation induced increased expression of IL-6 and TNF-α from satellite cells in uninfected TG. In latently infected TG, prior to reactivation, all satellite cells were TNF-α⁺ and most were also IL-6⁺. Reactivation, evidenced by HSV-1 antigens and/or infiltrating immune cells, occurred in 28 of 45 (62%) TG samples. Viral antigens were present in the TG in neurons, often disintegrating on days 2 to 6 after irradiation. Infected neurons were usually surrounded by satellite cells and the foci of immune cells producing TNF-α and/or IL-6. IL-4⁺ cells were detected as early as day 3 and were more numerous by day 10 (a very few IL-2⁺ and/or IFN-γ⁺ cells were seen at this time). No IL-10 was detected at any time. Our observations indicate that UV irradiation of the cornea may modulate cytokine production by satellite cells. We confirm that neurons are the site of reactivation and that they probably do not survive this event. The predominance of TNF-α and IL-6 following reactivation parallels primary infection in the TG and suggests a role in viral clearance. The presence of Th2-type cytokines (IL-4 and IL-6) indicates a role for antibody. Thus, several clearance mechanisms may be at work.     

Intracameral Interleukin 1β, 6, 8, 10, 12p,Tumor Necrosis Factor α and Vascular Endothelial Growth Factor and Axial Length in Patients with Cataract

ObjectiveTo assess associations between the aqueous humour concentration of interleukin IL-1β, IL-6, IL-8, IL-10 and IL-12p, tumor necrosis factor α (TNF-α) and vascular endothelial growth factor (VEGF) and axial length in eyes with cataract.MethodsThe hospital-based investigation included patients who underwent cataract surgery between March 2014 and April 2014. Using aqueous humour collected at the start of cataract surgery, the interleukins IL-1β, IL-6, IL-8, IL-10 and IL-12p, TNF-α and VEGF were examined using a cytometric bead array. Axial length was determined by partial coherence laser interferometry (IOL Master).ResultsThe study included 33 patients with cataract (33 eyes) with a mean age of 69.2±10.8 years (range:50–87 years) and a mean axial length of 24.7±1.9 mm (range:22.6–31.5 mm). Lower aqueous concentration of VEGF was significantly associated with longer axial length (VEGF concentration (pg/mL) = -5.12 x Axial Length (mm) + 163; correlation coefficient r = -0.41; P<0.001) and more myopic refractive error (VEGF concentration (pg/mL) = 1.27xspherical equivalent (diopters)+44.8; r = 0.383; P = 0.002). The aqueous concentrations of all other substances were not significantly (all P>0.10) associated with axial length or refractive error.ConclusionsHigher intravitreal concentrations of VEGF were measured in eyes with a longer axial length, while the intraocular concentrations of IL-1β, IL-6, IL-8, IL-10, IL-12p and TNF-α were not correlated with axial length. The lower concentration of VEGF in axially elongated eyes may be one of the reasons for the lower prevalence of age-related macular degeneration and diabetic retinopathy in myopic eyes.     

S100-β aggravates spinal cord injury via activation of M1 macrophage phenotype

Objectives:S100-β has been identified as a sensitive biomarker in central nervous system injuries. However, the functions and mechanisms of S100-β are unknown in spinal cord injury.Methods:Spinal cord injury (SCI) mouse model was generated by surgical operation, microglia activation model was established by inducing BV-2 cells with LPS. The SCI model was evaluated by Basso-Beattie-Bresnahan (BBB) behavioral score, HE staining, and Nissl staining. The expression level of S100-β was detected by qRT-PCR, western blot, and immunofluorescence. qRT-PCR and western blot were used to detect the expression of iNOS and CD16. Pro-inflammatory cytokines TNF-α and IL-1β levels were detected by qRT-PCR and ELISA.Results:The expression of IL-1β, TNF-α, iNOS, and CD16 increased at 3^rd day after SCI. In BV2 microglia, LPS treatment promoted the expression of S100-β, IL-1β, TNF-α, iNOS, and CD16. Knockdown of S100-β reduced the expression of iNOS stimulated by LPS. Over-expression of S100-β increased IL-1β and TNF-α, and S100-β inhibition suppressed IL-1β and TNF-α. In SCI mice, knockdown of S100-β attenuated the spinal cord injury and inhibited the expression of iNOS, IL-1β, and TNF-α.Conclusions:Down-regulation of S100-β could inhibit the pathogenesis of SCI and inhibit the activation of M1 macrophages. S100-β may be a useful diagnostic biomarker or therapeutic target for SCI.     

Demethylation of MicroRNA-124a Genes Attenuated Proliferation of Rheumatoid Arthritis Derived Fibroblast-Like Synoviocytes and Synthesis of Tumor Necrosis Factor-α

ObjectiveTo examine the impact of 5-Aza-2ʹ-deoxycytidine (5-AzadC) on methylation status of miR-124a genes in rheumatoid arthritis (RA) associated fibroblast-like synoviocytes (FLS) and its effect on RA-FLS proliferation and TNF-α expression.ResultsAfter 5-AzadC treatment, the expression of miR-124a was significantly increased compared with the control group (1.545 ± 0.189 vs 0.836 ± 0.166, p = 0.001). On the other hand, 5-AzadC significantly reduced IL-1β-mediated cell proliferation by nearly 2.5 fold (p = 0.006). Also, the level of TNF-α secreted from the cells treated with IL-1β plus 5-AzadC was considerably less than that from the cells treated with IL-1β alone (324.99 ± 22.73 ng/L vs 387.91 ± 58.51 ng/L, p = 0.022). After transfection with miR-124a inhibitor in RA-FLS treated with IL-1β plus 5-AzadC, the cell proliferation was increased by 18.2% and the TNF-α expression was increased by 19.0% (p = 0.001 and 0.011, respectively).ConclusionMethylation of miR-124a genes contributed to IL-1β-mediated RA-FLS proliferation and TNF-α expression.     

The inhibiting effect of glucosamine sulfate combined with loxoprofen sodium on chondrocyte apoptosis in rats with knee osteoarthritis

Objectives:To explore the efficacy of glucosamine sulfate (GS) combined with loxoprofen sodium (LS) in rats with knee osteoarthritis (KOA) and its effect on chondrocytes.Methods:We randomly assigned 40 SPF SD rats to normal group (NG), control group (CG), treatment group (TG), and model group (MG). CG and TG were processed with continuous irrigation of LS and GS. NG and MG were given normal saline. We collected 3 mL of venous blood from the rat’s lower limb for the detection of serum IL-1β, IL-6, IL-8, and TNF-α by ELISA. Four weeks after irrigation, 5 rats in each group were randomly selected for anesthesia. The water content was detected, and the chondrocytes were collected. MTT assay was used to detect apoptosis, and Western blot (WB) to measure concentrations of Bax, Bcl-2, Caspase3, Caspase9, TLR4, and NF-kB.Results:The levels of IL-1 β, IL-6, IL-8, and TNF-α decreased in CG and TG, but increased in MG (P<0.05). After treatment, the expression of inflammatory factors was highest in MG (P<0.05).Conclusions:GS combined with LS showed good efficacy in rats with knee osteoarthritis, which may be achieved by inhibiting the expression of inflammatory factors and knee chondrocyte apoptosis via the TLR4-NF-kB pathway.     

Effects of High-Intensity Swimming on Lung Inflammation and Oxidative Stress in a Murine Model of DEP-Induced Injury

Studies have reported that exposure to diesel exhaust particles (DEPs) induces lung inflammation and increases oxidative stress, and both effects are susceptible to changes via regular aerobic exercise in rehabilitation programs. However, the effects of exercise on lungs exposed to DEP after the cessation of exercise are not clear. Therefore, the aim of this study was to evaluate the effects of high-intensity swimming on lung inflammation and oxidative stress in mice exposed to DEP concomitantly and after exercise cessation. Male Swiss mice were divided into 4 groups: Control (n = 12), Swimming (30 min/day) (n = 8), DEP (3 mg/mL—10 μL/mouse) (n = 9) and DEP+Swimming (n = 8). The high-intensity swimming was characterized by an increase in blood lactate levels greater than 1 mmoL/L between 10th and 30th minutes of exercise. Twenty-four hours after the final exposure to DEP, the anesthetized mice were euthanized, and we counted the number of total and differential inflammatory cells in the bronchoalveolar fluid (BALF), measured the lung homogenate levels of IL-1β, TNF-α, IL-6, INF-ϫ, IL-10, and IL-1ra using ELISA, and measured the levels of glutathione, non-protein thiols (GSH-t and NPSH) and the antioxidant enzymes catalase and glutathione peroxidase (GPx) in the lung. Swimming sessions decreased the number of total cells (p<0.001), neutrophils and lymphocytes (p<0.001; p<0.05) in the BALF, as well as lung levels of IL-1β (p = 0.002), TNF-α (p = 0.003), IL-6 (p = 0.0001) and IFN-ϫ (p = 0.0001). However, the levels of IL-10 (p = 0.01) and IL-1ra (p = 0.0002) increased in the swimming groups compared with the control groups, as did the CAT lung levels (p = 0.0001). Simultaneously, swimming resulted in an increase in the GSH-t and NPSH lung levels in the DEP group (p = 0.0001 and p<0.002). We concluded that in this experimental model, the high-intensity swimming sessions decreased the lung inflammation and oxidative stress status during DEP-induced lung inflammation in mice.     

Lyophilized Powder of Catalpol and Puerarin Protects Neurovascular Unit from Stroke

Hunting for an effective medicine for brain stroke has been a medical task in neuroscience for decades. The present research showed that the lyophilized Powder of Catalpol and Puerarin (C-P) in all the tested doses (65.4 mg/kg, 32.7 mg/kg, 16.4 mg/kg) significantly reduced the neurological deficiency, infarct volume and apoptotic cells in ischemic/reperfusion (I/R) rats. It also promoted astrocyte processes and prolonged neuron axons in infarct area. Further, it decreased MDA, NO, NF-κB/p65, TNF-α, IL-1β and IL-6 and enhanced the EPOR and GAF-43. 65.4 mg/kg and 32.7 mg/kg C-P could up-regulated EPO and VEGF significantly. In vitro, 49 μg/mL and 24.5 μg/mL C-P decreased the leakage of sodium fluorescein and increased the activity of γ-GTP. Additionally, it increased SOD and decreased MDA, NO, and LDH and decreased NF-κB/p65, TNF-α, IL-1β and IL-6 and unregulated EPO, EPOR, VEGF, and GAP-43. Only the dose of 49 μg/mL increased TEER and Claudin-5 and turned the typically damaged morphologies of neurons, astrocytes and endothelium into a favorable trend. These data imply that C-P improved the recovery of neurological deficiency in motor, sense, balance and reflex, and protected the whole NVU by anti-oxidative stress, anti-inflammation and up-regulating some protective factors. This research provides a candidate medicine for brain stroke and, at the same time, a pattern for drug study targeting NVU in vitro.     

Effect of short-time treatment with TNF-α on stem cell activity and barrier function in enteroids

Although tumor necrosis factor-α (TNF-α) is a known major inflammatory mediator in inflammatory bowel disease (IBD) and has various effects on intestinal epithelial cell (IEC) homeostasis, the changes in IECs in the early inflammatory state induced during short-time treatment (24 h) with TNF-α remain unclear. In this study, we investigated TNF-α-induced alterations in IECs in the early inflammatory state using mouse jejunal organoids (enteroids). Of the inflammatory cytokines, i.e., TNF-α, IL-1β, IL-6, and IL-17, only TNF-α markedly increased the mRNA level of macrophage inflammatory protein 2 (MIP-2; the mouse homologue of interleukin-8), which is induced in the early stages of inflammation. TNF-α stimulation (3 h and 6 h) decreased the mRNA level of the stem cell markers leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) and polycomb group ring finger 4 and the progenitor cell marker prominin-1, which is also known as CD133. In addition, TNF-α treatment (24 h) decreased the number of Lgr5-positive cells and enteroid proliferation. TNF-α stimulation at 3 h and 6 h also decreased the mRNA level of chromogranin A and mucin 2, which are respective markers of enteroendocrine and goblet cells. Moreover, enteroids treated with TNF-α (24 h) not only decreased the integrity of tight junctions and cytoskeletal components but also increased intercellular permeability in an influx test with fluorescent dextran, indicating disrupted intestinal barrier function. Taken together, our findings indicate that short-time treatment with TNF-α promotes the inflammatory response and decreases intestinal stem cell activity and barrier function.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10616-021-00487-y.     

Attenuated expression of tenascin-c in ovalbumin-challenged STAT4-/- mice

Background

Asthma leads to structural changes in the airways, including the modification of extracellular matrix proteins such as tenascin-C. The role of tenascin-C is unclear, but it might act as an early initiator of airway wall remodelling, as its expression is increased in the mouse and human airways during allergic inflammation. In this study, we examined whether Th1 or Th2 cells are important regulators of tenascin-C in experimental allergic asthma utilizing mice with impaired Th1 (STAT4-/-) or Th2 (STAT6-/-) immunity.

Methods

Balb/c wildtype (WT), STAT4-/- and STAT6-/- mice were sensitized with intraperitoneally injected ovalbumin (OVA) followed by OVA or PBS airway challenge. Airway hyperreactivity (AHR) was measured and samples were collected. Real time PCR and immunohistochemistry were used to study cytokines and differences in the expression of tenascin-C. Tenascin-C expression was measured in human fibroblasts after treatment with TNF-α and IFN-γ in vitro.

Results

OVA-challenged WT mice showed allergic inflammation and AHR in the airways along with increased expression of TNF-α, IFN-γ, IL-4 and tenascin-C in the lungs. OVA-challenged STAT4-/- mice exhibited elevated AHR and pulmonary eosinophilia. The mRNA expression of TNF-α and IFN-γ was low, but the expression of IL-4 was significantly elevated in these mice. OVA-challenged STAT6-/- mice had neither AHR nor pulmonary eosinophilia, but had increased expression of mRNA for TNF-α, IFN-γ and IL-4. The expression of tenascin-C in the lungs of OVA-challenged STAT4-/- mice was weaker than in those of OVA-challenged WT and STAT6-/- mice suggesting that TNF-α and IFN-γ may regulate tenascin-C expression in vivo. The stimulation of human fibroblasts with TNF-α and IFN-γ induced the expression of tenascin-C confirming our in vivo findings.

Conclusions

Expression of tenascin-C is significantly attenuated in the airways of STAT4-/- mice, which may be due to the impaired secretion of TNF-α and IFN-γ in these mice.     

Acute Systemic Infection with Dengue Virus Leads to Vascular Leakage and Death through Tumor Necrosis Factor-α and Tie2/Angiopoietin Signaling in Mice Lacking Type I and II Interferon Receptors

Severe dengue is caused by host responses to viral infection, but the pathogenesis remains unknown. This is, in part, due to the lack of suitable animal models. Here, we report a non-mouse-adapted low-passage DENV-3 clinical isolate, DV3P12/08, derived from recently infected patients. DV3P12/08 caused a lethal systemic infection in type I and II IFN receptor KO mice (IFN-α/β/γR KO mice), which have the C57/BL6 background. Infection with DV3P12/08 induced a cytokine storm, resulting in severe vascular leakage (mainly in the liver, kidney and intestine) and organ damage, leading to extensive hemorrhage and rapid death. DV3P12/08 infection triggered the release of large amounts of TNF-α, IL-6, and MCP-1. Treatment with a neutralizing anti-TNF-α antibody (Ab) extended survival and reduced liver damage without affecting virus production. Anti-IL-6 neutralizing Ab partly prolonged mouse survival. The anti-TNF-α Ab suppressed IL-6, MCP-1, and IFN-γ levels, suggesting that the severe response to infection was triggered by TNF-α. High levels of TNF-α mRNA were expressed in the liver and kidneys, but not in the small intestine, of infected mice. Conversely, high levels of IL-6 mRNA were expressed in the intestine. Importantly, treatment with Angiopoietin-1, which is known to stabilize blood vessels, prolonged the survival of DV3P12/08-infected mice. Taken together, the results suggest that an increased level of TNF-α together with concomitant upregulation of Tie2/Angiopoietin signaling have critical roles in severe dengue infection.     

Increased Pro-Inflammatory Cytokines,C-Reactive Protein and Nerve Growth Factor Expressions in Serum of Patients with Interstitial Cystitis/Bladder Pain Syndrome

Objective

The etiology and pathogenesis of interstitial cystitis/bladder pain syndrome (IC/BPS) are unclear. Chronic inflammation is considered the main pathology of IC/BPS. This study measured the serum c-reactive protein (CRP), nerve growth factor (NGF) and pro-inflammatory cytokine/chemokine interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and IL-8 expression in patients with IC/BPS to elucidate the involvement of systemic inflammation in IC/BPS.

Methods

Serum samples were collected from 30 IC/BPS patients and 26 control subjects. The concentrations of serum nerve growth factor (NGF), IL-1β, IL-6, TNF-α, and IL-8 were quantified using a bead-based, human serum adipokine panel kit. Serum C-reactive protein (CRP) was also assessed. Differences of serum CRP, NGF, IL-1β, IL-6, TNF-α, and IL-8 levels between the IC/BPS patients and controls were compared, and correlations between CRP and pro-inflammatory cytokines and chemokine were also evaluated.

Results

The results showed that CRP level (p = 0.031), NGF (p = 0.015) and pro-inflammatory cytokines/chemokine IL-1β, IL-6, TNF-α, and IL-8 levels were significantly higher in the patients with IC/BPS than among controls (all p<0.001). Significant associations were observed between IL-1β and IL-8 (p<0.001), IL-6 and CRP (p = 0.01), IL-6 and IL-8 (p = 0.02), and IL-6 and TNF-α (p = 0.03).

Conclusion

Increased pro-inflammatory cytokines/chemokine (IL-1β, IL-6, TNF-α, and IL-8) expression in the sera of IC/BPS patients implies not only mast cell activation, but also that other inflammatory mediators play important roles in the pathogenesis of IC/BPS. Thus, for some patients, IC/BPS is considered a chronic inflammatory disease.     

IL-12p40 Deficiency Leads to Uncontrolled Trypanosoma cruzi Dissemination in the Spinal Cord Resulting in Neuronal Death and Motor Dysfunction

Chagas’ disease is a protozoosis caused by Trypanosoma cruzi that frequently shows severe chronic clinical complications of the heart or digestive system. Neurological disorders due to T. cruzi infection are also described in children and immunosuppressed hosts. We have previously reported that IL-12p40 knockout (KO) mice infected with the T. cruzi strain Sylvio X10/4 develop spinal cord neurodegenerative disease. Here, we further characterized neuropathology, parasite burden and inflammatory component associated to the fatal neurological disorder occurring in this mouse model. Forelimb paralysis in infected IL-12p40KO mice was associated with 60% (p<0.05) decrease in spinal cord neuronal density, glutamate accumulation (153%, p<0.05) and strong demyelization in lesion areas, mostly in those showing heavy protein nitrosylation, all denoting a neurotoxic degenerative profile. Quantification of T. cruzi 18S rRNA showed that parasite burden was controlled in the spinal cord of WT mice, decreasing from the fifth week after infection, but progressive parasite dissemination was observed in IL-12p40KO cords concurrent with significant accumulation of the astrocytic marker GFAP (317.0%, p<0.01) and 8-fold increase in macrophages/microglia (p<0.01), 36.3% (p<0.01) of which were infected. Similarly, mRNA levels for CD3, TNF-α, IFN-γ, iNOS, IL-10 and arginase I declined in WT spinal cords about the fourth or fifth week after infection, but kept increasing in IL-12p40KO mice. Interestingly, compared to WT tissue, lower mRNA levels for IFN-γ were observed in the IL-12p40KO spinal cords up to the fourth week of infection. Together the data suggest that impairments of parasite clearance mechanisms in IL-12p40KO mice elicit prolonged spinal cord inflammation that in turn leads to irreversible neurodegenerative lesions.     

TREK-1 Regulates Cytokine Secretion from Cultured Human Alveolar Epithelial Cells Independently of Cytoskeletal Rearrangements

BackgroundTREK-1 deficient alveolar epithelial cells (AECs) secrete less IL-6, more MCP-1, and contain less F-actin. Whether these alterations in cytokine secretion and F-actin content are related remains unknown. We now hypothesized that cytokine secretion from TREK-1-deficient AECs was regulated by cytoskeletal rearrangements.MethodsWe determined F-actin and α-tubulin contents of control, TREK-1-deficient and TREK-1-overexpressing human A549 cells by confocal microscopy and western blotting, and measured IL-6 and MCP-1 levels using real-time PCR and ELISA.ResultsCytochalasin D decreased the F-actin content of control cells. Jasplakinolide increased the F-actin content of TREK-1 deficient cells, similar to the effect of TREK-1 overexpression in control cells. Treatment of control and TREK-1 deficient cells with TNF-α, a strong stimulus for IL-6 and MCP-1 secretion, had no effect on F-actin structures. The combination of TNF-α+cytochalasin D or TNF-α+jasplakinolide had no additional effect on the F-actin content or architecture when compared to cytochalasin D or jasplakinolide alone. Although TREK-1 deficient AECs contained less F-actin at baseline, quantified biochemically, they contained more α-tubulin. Exposure to nocodazole disrupted α-tubulin filaments in control and TREK-1 deficient cells, but left the overall amount of α-tubulin unchanged. Although TNF-α had no effect on the F-actin or α-tubulin contents, it increased IL-6 and MCP-1 production and secretion from control and TREK-1 deficient cells. IL-6 and MCP-1 secretions from control and TREK-1 deficient cells after TNF-α+jasplakinolide or TNF-α+nocodazole treatment was similar to the effect of TNF-α alone. Interestingly, cytochalasin D decreased TNF-α-induced IL-6 but not MCP-1 secretion from control but not TREK-1 deficient cells.ConclusionAlthough cytochalasin D, jasplakinolide and nocodazole altered the F-actin and α-tubulin structures of control and TREK-1 deficient AEC, the changes in cytokine secretion from TREK-1 deficient cells cannot be explained by cytoskeletal rearrangements in these cells.     

Death receptor 6 (DR6) antagonist antibody is neuroprotective in the mouse SOD1G93A model of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the death of motor neurons, axon degeneration, and denervation of neuromuscular junctions (NMJ). Here we show that death receptor 6 (DR6) levels are elevated in spinal cords from post-mortem samples of human ALS and from SOD1^G93A transgenic mice, and DR6 promotes motor neuron death through activation of the caspase 3 signaling pathway. Blocking DR6 with antagonist antibody 5D10 promotes motor neuron survival in vitro via activation of Akt phosphorylation and inhibition of the caspase 3 signaling pathway, after growth factor withdrawal, sodium arsenite treatment or co-culture with SOD1^G93A astrocytes. Treatment of SOD1^G93A mice at an asymptomatic stage starting on the age of 42 days with 5D10 protects NMJ from denervation, decreases gliosis, increases survival of motor neurons and CC1⁺ oligodendrocytes in spinal cord, decreases phosphorylated neurofilament heavy chain (pNfH) levels in serum, and promotes motor functional improvement assessed by increased grip strength. The combined data provide clear evidence for neuroprotective effects of 5D10. Blocking DR6 function represents a new approach for the treatment of neurodegenerative disorders involving motor neuron death and axon degeneration, such as ALS.     

Exercise training is more effective than resveratrol supplementation on alleviation of inflammation in peritoneal macrophages of high fat diet mice

[Purpose]

This study investigated the effect of exercise training and resveratrol supplementation with low fat diet on proinflammatory profiles by Lipopolysaccharide (LPS)-stimulation in peritoneal macrophage of high fat diet mice.

[Methods]

To accomplish the purpose of this study, C57BL/6 male mice were fed high fat diet (45% fat diet) for 8 weeks. Then these mice were divided into 3 groups; HLC (high fat diet and low fat diet for 8 weeks as the control, n=10), HLR (high fat diet and low fat diet for 8 weeks with resveratrol supplementation, n=10). HLE (high fat diet and low fat diet for 8 weeks with moderate exercise training, n=10). Resveratrol (10 mg/kg) was administrated once a day, 5 days/week for 8 weeks. Exercise training was performed for 8 weeks on a treadmill running for 30-60 min/day at 10-22 m/min, 0% grade, 5 days/week. After exercise training, all the peritoneal macrophage was collected and LPS (0, 0.5, 1.0 μg/ml) were used to stimulate the cells. Then peritoneal macrophage TNF-α, IL-6, MCP-1, IL12p70, IFN-γ, IL-10 were measured by BD cytometric bead array mouse inflammation kit.

[Results]

As a result, body weight and total cholesterol were significantly reduced in HLE compared with HLC (p<.05). Also, TNF-α and MCP-1 were decreased in HLE compared with HLC (p<.05) by LPS-stimulation (0, 0.5, 1.0 μg/ml) and IL-6, IL-12p70 and IFN-r were decreased in HLE compared with HLC (p<.05) by LPS-stimulation (1.0 μg/ml). But resveratrol supplementation did not affect the result.

[Conclusion]

These findings suggest that exercise training has beneficial effects on body weight, total cholesterol, peritoneal macrophage and proinflammatory cytokine in high fat diet mice.     

Autophagic Impairment Contributes to Systemic Inflammation-Induced Dopaminergic Neuron Loss in the Midbrain

Background

Neuroinflammation plays an important role in the pathogenesis of Parkinson’s disease (PD), inducing and accelerating dopaminergic (DA) neuron loss. Autophagy, a critical mechanism for clearing misfolded or aggregated proteins such as α-synuclein (α-SYN), may affect DA neuron survival in the midbrain. However, whether autophagy contributes to neuroinflammation-induced toxicity in DA neurons remains unknown.

Results

Intraperitoneal injection of lipopolysaccharide (LPS, 5 mg/kg) into young (3-month-old) and aged (16-month-old) male C57BL/6J mice was observed to cause persistent neuroinflammation that was associated with a delayed and progressive loss of DA neurons and accumulation of α-SYN in the midbrain. The autophagic substrate-p62 (SQSTM1) persistently increased, whereas LC3-II and HDAC6 exhibited early increases followed by a decline. In vitro studies further demonstrated that TNF-α induced cell death in PC12 cells. Moreover, a sublethal dose of TNF-α (50 ng/ml) increased the expression of LC3-II, p62, and α-SYN, implying that TNF-α triggered autophagic impairment in cells.

Conclusion

Neuroinflammation may cause autophagic impairment, which could in turn result in DA neuron degeneration in midbrain.