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Background: The durable oocyst wall formed from the contents of wall-forming bodies (WFBs) protects Eimeria parasites from harsh conditions and enhances parasite transmission. Comprehending the contents of WFBs and proteins involved in oocyst wall formation is pivotal to understanding the mechanism of the oocyst wall formation and the search for novel targets to disrupt parasite transmission. Methods: Total proteins extracted from WFBs and the oocyst wall of Eimeria necatrix were subjected to comparative proteomic analysis using tandem mass tag in conjunction with liquid chromatography tandem-mass spectrometry techniques. After functional clustering analysis of the identified proteins, three proteins, including E. necatrix disulfide isomerase (EnPDI), thioredoxin (EnTrx) and phosphoglycerate kinase (EnPGK), were selected for further study to confirm their potential roles in oocyst wall formation. Results: A total of 3009 and 2973 proteins were identified from WFBs and the oocyst wall of E. necatrix, respectively. Among these proteins, 1102 were identified as differentially expressed proteins, of which 506 were upregulated and 596 downregulated in the oocyst wall compared to the WFBs. A total of 108 proteins, including compositional proteins of the oocyst wall, proteases, oxidoreductases, proteins involved in glycosylation, proteins involved in synthesis of the acid-fast lipid layer and proteins related to transport, were proposed to be involved in oocyst wall formation. The approximate molecular sizes of native EnPDI, EnTrx and EnPGK proteins were 55, 50 and 45 kDa, respectively. EnPDI was present in both type 1 and type 2 WFBs, EnTrx was present only in type 2 WFB2 and EnPGK was present only in type 1 WFBs, whereas all of them were localized to the outer layer of the oocyst wall, indicating that all of them participate in the formation of the oocyst wall. Conclusions: To the best of our knowledge, this is the first report on the proteomes of WFBs and the oocyst wall of E. necatrix. The data obtained from this study form a basis for deciphering the molecular mechanisms underlying oocyst wall formation of Eimeria parasites. They also provide valuable resources for future studies on the development of novel therapeutic agents and vaccines aimed at combating coccidian transmission. [ABSTRACT FROM AUTHOR]

Background: Eimeria parasite infection occurs via ingestion of oocysts. The robust, bilayer oocyst wall is formed from the contents of wall-forming bodies (WFBs), WFB1 and WFB2, located exclusively in macrogametocytes. Eimeria necatrix gametocyte proteins 22 and 59 (EnGAM22 and EnGAM59) have been found to localize to WFBs and the oocyst wall. However, the exact localization of these two proteins is not clear. Methods: WFBs of E. necatrix were extracted from purified gametocytes using a cutoff filter and the extracts of purified WFBs and gametocytes were analyzed using sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. Then, the localization of EnGAM22 and EnGAM59 proteins was determined using an indirect immunofluorescence assay. Finally, the development of macrogametocytes and the oocyst wall of E. necatrix was analyzed using laser confocal microscopy and scanning electron microscopy. Results: Purified WFBs had the same shape and size as those observed in macrogametocytes. EnGAM22 protein localized to WFB1, whereas EnGAM59 protein localized to WFB2. Both EnGAM22 and EnGAM59 native proteins were detected in the extracts of WFBs and gametocytes. The outer layer of the oocyst wall was formed by the release of the contents of WFB1 at the surface of the macrogametocyte to form an anti-EnGAM22 positive layer. WFB2 then appeared to give rise to the inner layer, which was anti-EnGAM59 positive. Conclusions: EnGAM22 and EnGAM59 proteins localized to WFB1 and WFB2 and were involved in the formation of the outer and inner layers of the oocyst wall of E. necatrix, respectively. The processes of macrogametogenesis and oocyst wall formation of E. necatrix are similar to other Eimeria parasites. The anti-EnGAM22 antibody could be used as a tool to track the transport and secretion of proteins in WFB1 during oocyst development. [ABSTRACT FROM AUTHOR]

Background: Anterior resection syndrome (ARS) is characterized by the diverse and interchangeable evacuatory symptoms that may occur following distal colorectal resection. We aimed to investigate the effect and potential mechanisms of ozone perfusion on rats with anterior rectal resection (ARR).Material and Methods: After establishment of rat ARR model, 20, 40 and 80 ug/ml ozone was used to treat rats by enema administration. The pathological examination of intestinal tissue was detected using hematoxylin-eosin staining. The rate of loose stools, minimum threshold volume of abdominal withdrawal reflex (AWR) and Bristol grade were used to evaluate the degree of abnormal defecation function. Subsequently, the levels of oxidative stress- and inflammation-related markers, 5-hydroxytryptamine (5-HT), inducible nitric oxide synthase (iNOS) and nitric oxide (NO) in the serum and intestinal tissue were determined with the corresponding kits. Meanwhile, the expression of nuclear factor kappa B (NF-κB) p65, transient receptor potential vanilloid (TRPV)1, TRPV4, iNOS and 5-HT receptor 3A (5-HTR3A) was determined with RT-qPCR and western blotting.Results: Ozone administration (20 and 40 ug/ml) significantly alleviated the pathological changes of intestinal tissue-induced by ARR, accompanied by the decreased loose stools rate, Bristol score and increased abdominal withdraw reflex. However, 80 ug/ml of ozone intervention played opposite roles in the aforementioned changes with 20 and 40 ug/ml of ozone. Additionally, remarkably elevated reactive oxygen species (ROS), malonaldehyde (MDA), superoxide dismutase (SOD), 5-HT, iNOS and NO levels were observed in the ozone-treated groups (20 and 40 ug/ml), while high dose of ozone drastically improved ROS, MDA, 5-HT, iNOS and NO levels but reduced the activity of SOD. Consistently, the contents of inflammatory factors were decreased after low and middle doses of ozone administration. However, high dose of ozone aggravated the inflammatory injury. Moreover, 20 and 40 ug/ml ozone upregulated TRPV1 and TRPV4 expression but downregulated 5-HTR3A expression, which was restored after 80 ug/ml of ozone intervention. Remarkably, the levels of NF-κB p65 and iNOS were dose-dependently enhanced following ozone treatment.Conclusions: Taken together, low concentration of ozone attenuated intestinal injury induced by ARR via balancing oxidative stress and inflammation, but high concentration of ozone exacerbated the intestinal injury, which might be related to the 5-HT and TRPV signaling. [ABSTRACT FROM AUTHOR]