scholarly journals Inflammation modulates regeneration in the acute or chronically damaged zebrafish retina

2021 ◽  
Author(s):  
Maria Iribarne ◽  
David Hyde

Unlike mammals, zebrafish regenerate in response to retinal damage. Because microglia are activated by retinal damage, we investigated their role during regeneration following acute or chronic damage. At three weeks-post-fertilization (wpf), fish exhibiting NMDA-induced acute damage or cone photoreceptor-specific chronic degeneration, the gold rush (gosh) mutant, displayed reactive microglia and Müller glia proliferation. Retinas treated to inhibit the immune response lacked reactive microglia and possessed fewer PCNA-positive cells, while LPS treatment increased microglia and PCNA-labeled cells. NMDA-injured retinas upregulated the expression of il-1β and tnf-α pro-inflammatory cytokine genes, followed by increased expression of il-10 and arg1 anti-inflammatory/remodeling cytokine genes. An early and transiently TNF-α pro-inflammatory microglia population was identified in the NMDA-damaged retina. In contrast, gosh mutant retinas exhibited a mild increase of pro-inflammatory cytokine gene expression concurrently with a greater increased in anti-inflammatory/remodeling cytokine gene expression. Few TNF-α pro-inflammatory microglia were observed in the gosh retina. How inflammation regulates regeneration in zebrafish would provide important clues towards improving the therapeutic strategies for repairing injured mammalian tissues.

2015 ◽  
Vol 308 (12) ◽  
pp. R1062-R1069 ◽  
Author(s):  
Jennifer E. Dumaine ◽  
Noah T. Ashley

Sleep deprivation induces acute inflammation and increased glucocorticosteroids in vertebrates, but effects from fragmented, or intermittent, sleep are poorly understood. Considering the latter is more representative of sleep apnea in humans, we investigated changes in proinflammatory (IL-1β, TNF-α) and anti-inflammatory (TGF-β1) cytokine gene expression in the periphery (liver, spleen, fat, and heart) and brain (hypothalamus, prefrontal cortex, and hippocampus) of a murine model exposed to varying intensities of sleep fragmentation (SF). Additionally, serum corticosterone was assessed. Sleep was disrupted in male C57BL/6J mice using an automated sleep fragmentation chamber that moves a sweeping bar at specified intervals (Lafayette Industries). Mice were exposed to bar sweeps every 20 s (high sleep fragmentation, HSF), 120 s (low sleep fragmentation, LSF), or the bar remained stationary (control). Trunk blood and tissue samples were collected after 24 h of SF. We predicted that HSF mice would exhibit increased proinflammatory expression, decreased anti-inflammatory expression, and elevated stress hormones in relation to LSF and controls. SF significantly elevated IL-1β gene expression in adipose tissue, heart (HSF only), and hypothalamus (LSF only) relative to controls. SF did not increase TNF-α expression in any of the tissues measured. HSF increased TGF-β1 expression in the hypothalamus and hippocampus relative to other groups. Serum corticosterone concentration was significantly different among groups, with HSF mice exhibiting the highest, LSF intermediate, and controls with the lowest concentration. This indicates that 24 h of SF is a potent inducer of inflammation and stress hormones in the periphery, but leads to upregulation of anti-inflammatory cytokines in the brain.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4423 ◽  
Author(s):  
Jennifer E. Dumaine ◽  
Noah T. Ashley

Obesity and sleep fragmentation (SF) are often co-occurring pro-inflammatory conditions in patients with obstructive sleep apnea. Leptin is a peptide hormone produced by adipocytes that has anorexigenic effects upon appetite while regulating immunity. The role of leptin in mediating inflammatory responses to SF is incompletely understood. Male C57BL/6j (lean) and ob/ob mice (leptin-deficient mice exhibiting obese phenotype) were subjected to SF or control conditions for 24 h using an automated SF chamber. Trunk blood and tissue samples from the periphery (liver, spleen, fat, and heart) and brain (hypothalamus, prefrontal cortex, and hippocampus) were collected. Quantitative PCR was used to determine relative cytokine gene expression of pro-inflammatory (IL-1β, TNF-α) and anti-inflammatory (TGF-β1) cytokines. Enzyme-linked immunosorbent assay (ELISA) was used to determine serum corticosterone concentration. Ob/ob mice exhibited elevated cytokine gene expression in liver (TNF-α, TGF-β1), heart (TGF-β1), fat (TNF-α), and brain (hippocampus, hypothalamus, prefrontal cortex: IL-1β, TNF-α) compared with wild-type mice. Conversely, leptin deficiency decreased pro-inflammatory cytokine gene expression in heart (IL-1β, TNF-α). SF significantly increased IL-1β and TNF-α gene expression in fat and TGF-β1 expression in spleen relative to controls, but only in wild-type mice. SF increased basal serum corticosterone regardless of genotype. Taken together, these findings suggest that leptin deficiency affects cytokine gene expression differently in the brain compared to peripheral tissues with minimal interaction from acute SF.


Nutrients ◽  
2015 ◽  
Vol 7 (8) ◽  
pp. 6313-6329 ◽  
Author(s):  
Kampeebhorn Boonloh ◽  
Veerapol Kukongviriyapan ◽  
Bunkerd Kongyingyoes ◽  
Upa Kukongviriyapan ◽  
Supawan Thawornchinsombut ◽  
...  

2010 ◽  
Vol 298 (1) ◽  
pp. C171-C181 ◽  
Author(s):  
Zachary A. Cooper ◽  
Arundhati Ghosh ◽  
Aditi Gupta ◽  
Tapan Maity ◽  
Ivor J. Benjamin ◽  
...  

We previously showed that exposure to febrile-range temperatures (FRT, 39.5–40°C) reduces LPS-induced TNF-α expression, in part through the direct interaction of heat shock factor-1 (HSF1) with the TNF-α gene promoter. However, it is not known whether exposure to FRT also modifies more proximal LPS-induced signaling events. Using HSF1-null mice, we confirmed that HSF1 is required for FRT-induced repression of TNF-α in vitro by LPS-stimulated bone marrow-derived macrophages and in vivo in mice challenged intratracheally with LPS. Exposing LPS-stimulated RAW 264.7 mouse macrophages to FRT reduced TNF-α expression while increasing IL-1β expression despite the two genes sharing a common myeloid differentiation protein-88 (MyD88)-dependent pathway. Global activation of the three LPS-induced signaling intermediates that lead to cytokine gene expression, ERK and p38 MAPKs and NF-κB, was not affected by exposing RAW 264.7 cells to FRT as assessed by ERK and p38 phosphorylation and NF-κB in vitro DNA-binding activity and activation of a NF-κB-dependent synthetic promoter. However, chromatin immunoprecipitation (ChIP) analysis demonstrated that exposure to FRT reduced LPS-induced recruitment of NF-κB p65 to the TNF-α promoter while simultaneously increasing its recruitment to the IL-1β promoter. These data suggest that FRT exerts its effects on cytokine gene expression in a gene-specific manner through distal effects on promoter activation rather than proximal receptor activation and signal transduction.


2017 ◽  
Vol 29 (4) ◽  
pp. 747 ◽  
Author(s):  
Reza Salehi ◽  
Marcos G. Colazo ◽  
Mohanathas Gobikrushanth ◽  
Urmila Basu ◽  
Divakar J. Ambrose

Postpartum uterine infections affect ovarian function and delay ovulation in cattle. As dietary fats can affect immune cell function, we investigated the influence of prepartum diets on postpartum uterine inflammatory status (UIS) as assessed 25 ± 1 days postpartum by endometrial cytology (normal: ≤8% polymorphonuclear cells (PMN) vs subclinical endometritis (SCE): >8% PMN) and associations between SCE, pro- and anti-inflammatory cytokine gene expression and ovarian function. During the last 5 weeks of gestation, dairy cows received a diet supplemented with 8% rolled sunflower (n = 10) or canola seed (n = 9) or no oilseed (n = 9). Ovaries were scanned until 35 days postpartum. Prepartum diets did not influence SCE, but a preovulatory-size follicle developed sooner (P ≤ 0.05), the interval to first ovulation was shorter and the proportion of cows ovulating within 35 days postpartum was greater in the sunflower seed group. Although mRNA expression of cytokines was not affected by diet, cows with SCE had higher (P ≤ 0.05) expression of interleukin-1β (IL1B), interleukin-8 (CXCL8), IL10 and tumour necrosis factor-α (TNF) than normal cows. The interval (mean ± s.e.m.) from calving to preovulatory-size follicle was shorter (P ≤ 0.05) in normal (13.2 ± 0.9 days) than SCE cows (18.7 ± 1.4 days). In summary, a prepartum diet supplemented with sunflower seed positively influenced postpartum ovarian function without affecting UIS or pro- and anti-inflammatory cytokine gene expression in endometrial cells.


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