ABSTRACT
Our previous studies have shown that recombinant human phospholipase D2 (rhPLD2) plays a modulator role on NF-κB and PKC signaling pathways. It also inhibits IL-5-induced inflammatory response in chronic asthmatic guinea pigs. Additionally, increasing evidence also has revealed that the adoptive transfer of induced regulatory T cells (Tregs) may be a therapeutic solution to airway allergic diseases. To investigate the epigenetic, transcriptomic and phenotypic variability of Treg population in an ovalbumin (OVA)-induced airway inflammation model derived from the induction of rhPLD2, OVA-induced asthmatic murine model is used in this study. The lung inflammation, eosinophil infiltration, the differentiation and proliferation of T helper cells and the amplification of Tregs were examined in this mouse model with and without rhPLD2 induction. Our data showed that rhPLD2 administration in asthmatic mice significantly increases CD4+CD25+ Foxp3+ Treg cell numbers and alleviates lung inflammation. The addition of rhPLD2 in vitro enhanced the demethylation of Treg-specificdemethylated region (TSDR) in iTregs, suggesting that rhPLD2 protein may be involved in improving the quality and quantity of Treg cells that eventually significantly reduces lung inflammation in asthmatic murine model. These results suggest that rhPLD2 could have a clinical impact treating patients with allergic airway inflammation via promoting and stabilizing iTreg differentiation and function.
Subject(s)
Asthma/drug therapy , Asthma/immunology , Forkhead Transcription Factors/metabolism , Inflammation/drug therapy , Interleukin-2 Receptor alpha Subunit/metabolism , Lung/pathology , Phospholipase D/therapeutic use , T-Lymphocytes, Regulatory/immunology , Adoptive Transfer , Animals , Asthma/pathology , CpG Islands/genetics , DNA Methylation/genetics , Disease Models, Animal , Eosinophils/pathology , Humans , Mice, Inbred BALB C , Models, Biological , Phospholipase D/pharmacology , Protein Stability , RNA, Messenger/genetics , RNA, Messenger/metabolism , Recombinant Proteins/pharmacology , Recombinant Proteins/therapeutic use , T-Lymphocytes, Regulatory/drug effectsABSTRACT
Mitochondria are important organelles in virtually all eukaryotic cells, and are involved in a wide range of physiological and pathophysiological processes. Besides the generation of cellular energy in the form of adenosine triphosphate, mitochondria are also involved in calcium homeostasis, reactive oxygen species production and the activation of the intrinsic cell death pathway, thus determining cell survival and death. Mitochondrial abnormalities have been implicated in a wide range of disorders, including neurodegenerative disease such as Parkinson's disease (PD), and considered as a primary cause and central event responsible for the progressive loss of dopaminergic neurons in PD. Thus, reversion or attenuation of mitochondrial dysfunction should alleviate the severity or progression of the disease. The present review systematically summarizes the possible mechanisms associated with mitochondriamediated dopaminergic neuron damage in PD, in an attempt to elucidate the requirement for further studies for the development of effective PD treatments.
