Pharmacological inhibition of poly (ADP-ribose) polymerase by olaparib, prevents acute lung injury associated cognitive deficits potentially through suppression of inflammatory response.
奥拉帕尼对聚 ADP 核糖聚合酶的药理抑制作用，可能通过抑制炎症反应来预防急性肺损伤相关认知缺陷。
- 作者列表："Sahu B","Narota A","Naura AS
:Acute lung injury (ALI) has been reported to be associated with high mortality rate. Moreover, ALI survivors, frequently present chronic cognitive deterioration. We have previously shown that 'two hit' (hydrochloric acid + lipopolysaccharide) induced ALI resulted in cognitive dysfunction through the induction of systemic inflammation. The present study was designed to explore the potential anti-inflammatory effects of olaparib (Poly ADP-ribose polymerase-1 inhibitor), on ALI mediated cognitive impairment. Olaparib was administered at dose of 5 mg/kg body weight (i.p.) 30 min before each hit. Data show that olaparib pre-treatment markedly reduced the neutrophil infiltration, alveolar capillary damage, inflammatory cytokines level (TNF-α/IL-1β/IL-6) and oxidative stress in the lungs at 24 h after ALI induction. Also, olaparib pre-treatment ameliorated the ALI associated cognitive impairment as assessed by Morris water maze test on weekly basis for 2 consecutive weeks. Further, restoration of cognitive function was associated with normalization of serum levels of TNF-α/IL-1β and improved the blood brain barrier (BBB) function, as reflected by data on expression of occludin/claudin-5 and extravasation of Evans-blue/FITC dextran in hippocampus at 1 week post injury. Finally, increased mRNA expression of VCAM-1, TNF-α and IL-1β and NF-κB activation in hippocampus indicate induction of neuro-inflammation, which was downregulated upon olaparib administration. Further, olaparib treatment 1 week after ALI induction blunted the systemic inflammation which was associated with improved BBB and cognitive function. Altogether, our results showed that olaparib protects against ALI and associated cognitive deficits in mice, and thus may offer a new treatment avenue in the area.
: 据报道，急性肺损伤 (ALI) 与高死亡率有关。此外，ALI 幸存者经常出现慢性认知恶化。我们之前的研究表明，'两次打击' (盐酸 + 脂多糖) 诱导的 ALI 通过诱导全身炎症导致认知功能障碍。本研究旨在探讨奥拉帕尼 (聚 ADP 核糖聚合酶-1 抑制剂) 对 ALI 介导的认知障碍的潜在抗炎作用。Olaparib 以 5 mg/kg 体重 (i.p.) 的剂量给药每次命中前 30 min。数据显示，奥拉帕尼治疗前明显减少中性粒细胞浸润，肺泡毛细血管损伤，炎性细胞因子水平 (TNF-α/il-1 β/IL-6) 和 ALI 诱导后 24 h 肺部的氧化应激。同样，olaparib 预处理改善了通过每周 Morris 水迷宫测试评估的 ALI 相关认知障碍，连续 2 周。此外，认知功能的恢复与血清 TNF-α/il-1 β 水平正常化相关，并改善血脑屏障 (BBB) 功能,伤后 1 周海马 occludin/claudin-5 表达和 Evans-blue/FITC 葡聚糖外渗的数据反映。最后，海马 VCAM-1 、 TNF-α 和 il-1 β mRNA 表达增加和 NF-κ b 活化提示神经炎症的诱导，奥拉帕尼给药后神经炎症下调。此外，在 ALI 诱导后 1 周，olaparib 治疗钝化了与改善 BBB 和认知功能相关的全身炎症。总之，我们的结果表明，olaparib 可预防小鼠 ALI 和相关的认知缺陷，从而可能在该地区提供新的治疗途径。
METHODS:BACKGROUND AND PURPOSE:A critical role for sphingosine kinase/sphingosine-1-phosphate (S1P) pathway in the control of airway function has been demonstrated in respiratory diseases. Here, we address S1P contribution in a mouse model of mild chronic obstructive pulmonary disease (COPD). EXPERIMENTAL APPROACH:C57BL/6J mice have been exposed to room air or cigarette smoke up to 11 months and killed at different time points. Functional and molecular studies have been performed. KEY RESULTS:Cigarette smoke caused emphysematous changes throughout the lung parenchyma coupled to a progressive collagen deposition in both peribronchiolar and peribronchial areas. The high and low airways showed an increased reactivity to cholinergic stimulation and α-smooth muscle actin overexpression. Similarly, an increase in airway reactivity and lung resistances following S1P challenge occurred in smoking mice. A high expression of S1P, Sph-K2 , and S1P receptors (S1P2 and S1P3 ) has been detected in the lung of smoking mice. Sphingosine kinases inhibition reversed the increased cholinergic response in airways of smoking mice. CONCLUSIONS AND IMPLICATIONS:S1P signalling up-regulation follows the disease progression in smoking mice and is involved in the development of airway hyperresponsiveness. Our study defines a therapeutic potential for S1P inhibitors in management of airways hyperresponsiveness associated to emphysema in smokers with both asthma and COPD.
METHODS::The interim results from this 90-day multi-dose, inhalation toxicology study with life-time post-exposure observation has shown an important fundamental difference in persistence and pathological response in the lung between brake dust derived from brake-pads manufactured with chrysotile, TiO2 or chrysotile alone in comparison to the amphiboles, crocidolite and amosite asbestos. In the brake dust exposure groups no significant pathological response was observed at any time. Slight macrophage accumulation of particles was noted. Wagner-scores, were from 1 to 2 (1 = air-control group) and were similar to the TiO2 group. Chrysotile being biodegradable, shows a weakening of its matrix and breaking into short fibers & particles that can be cleared by alveolar macrophages and continued dissolution. In the chrysotile exposure groups, particle laden macrophage accumulation was noted leading to a slight interstitial inflammatory response (Wagner-score 1-3). There was no peribronchiolar inflammation and occasional very slight interstitial fibrosis. The histopathology and the confocal analyses clearly differentiate the pathological response from amphibole asbestos, crocidolite and amosite, compared to that from the brake dust and chrysotile. Both crocidolite and amosite induced persistent inflammation, microgranulomas, and fibrosis (Wagner-scores 4), which persisted through the post exposure period. The confocal microscopy of the lung and snap-frozen chestwalls quantified the extensive inflammatory response and collagen development in the lung and on the visceral and parietal surfaces. The interim results reported here, provide a clear basis for differentiating the effects from brake dust exposure from those following amphibole asbestos exposure. The subsequent results through life-time post-exposure will follow.
METHODS::The respiratory tract is lined by a pseudo-stratified epithelium from the nose to terminal bronchioles. This first line of defense of the lung against external stress includes five main cell types: basal, suprabasal, club, goblet and multiciliated cells, as well as rare cells such as ionocytes, neuroendocrine and tuft/brush cells. At homeostasis, this epithelium self-renews at low rate but is able of fast regeneration upon damage. Airway epithelial cell lineages during regeneration have been investigated in the mouse by genetic labeling, mainly after injuring the epithelium with noxious agents. From these approaches, basal cells have been identified as progenitors of club, goblet and multiciliated cells, but also of ionocytes and neuroendocrine cells. Single-cell RNA sequencing, coupled to lineage inference algorithms, has independently allowed the establishment of comprehensive pictures of cell lineage relationships in both mouse and human. In line with genetic tracing experiments in mouse trachea, studies using single-cell RNA sequencing (RNAseq) have shown that basal cells first differentiate into club cells, which in turn mature into goblet cells or differentiate into multiciliated cells. In the human airway epithelium, single-cell RNAseq has identified novel intermediate populations such as deuterosomal cells, 'hybrid' mucous-multiciliated cells and progenitors of rare cells. Novel differentiation dynamics, such as a transition from goblet to multiciliated cells have also been discovered. The future of cell lineage relationships in the respiratory tract now resides in the combination of genetic labeling approaches with single-cell RNAseq to establish, in a definitive manner, the hallmarks of cellular lineages in normal and pathological situations.