Parasite Versus Host: Pathology and Disease
Eric S. Loker, Bruce V. Hofkin in Parasitology, 2023
Certain apicomplexans, including Toxoplasma gondii and Eimeria tenella, seem to produce what may be called a legitimate toxin; a 15 kD protein that acts as an actin-depolymerizing factor in infected cells. Members of the related genus Sarcocystis produce a homologous protein that acts in the same way. The case of Sarcocystis, which has a life cycle similar to T. gondii, is particularly interesting. Like T. gondii, the life cycle is heteroxenous, with gametogony and sporogony (see Figure 3.15) taking place in the intestine of the definitive host, with oocysts being shed in the feces. Herbivorous mammals (including humans) may inadvertently consume these oocysts whereupon they serve as intermediate hosts. The life cycle is completed when a predator consumes the intermediate host. But whereas only cats can serve as definitive hosts for T. gondii, various meat eaters, including humans, may act as definitive hosts for at least some Sarcocystis species. When humans become thus infected by consuming undercooked meat, they experience diarrhea, which has been attributed to the parasite-encoded toxic protein.
Abies Spectabilis (D. Don) G. Don (Syn. A. Webbiana Lindl.) Family: Coniferae
L.D. Kapoor in Handbook of Ayurvedic Medicinal Plants, 2017
Chemical constituents — Nutmegs yield 5 to 15% of a volatile oil and also 30 to 40% of fat, photosterin, starch, amylodextrin, coloring matter, and a saponin.69 They yield about 3% of total ash and about 0.2% of acid-insoluble ash. Essential oil of mace is of a yellowish color with the odor of mace, and consists of macene. Mace (arillus) contains a volatile oil (8 to 17%), a fixed oil, resin, fat, sugar, destrin, and mucilage.
Epithelial barrier dysfunction and cell migration induction via JNK/cofilin/actin by angubindin-1
Published in Tissue Barriers, 2020
Takumi Konno, Takayuki Kohno, Shin Kikuchi, Hiroshi Shimada, Seiro Satohisa, Tsuyoshi Saito, Masuo Kondoh, Takashi Kojima
To maintain the epithelial barrier, the presence of actin, which is one component of the cytoskeleton, is also important, and tricellular contacts are thought to have a specific mechanism in the regulation of the actin skeleton.9,10 Regulation of the epithelial barrier is one of the important functions of the actin cytoskeleton.11,12 Actin filaments are associated with the regulation of assembly and function of AJs and TJs.13–15 Cofilin is a member of the actin-depolymerizing factor (ADF)/cofilin family, which is a group of proteins that directly regulate actin dynamics.16 Dephosphorylation of phosphorylated cofilin activates its direct regulation of actin dynamics.16 It is reported that cofilin mediates tight junction opening by redistributing actin and tight junction proteins.17 It is also reported that the reversible increase in tight junction permeability induced by capsaicin, which is a pungent ingredient found in chili peppers, is mediated via cofilin-actin cytoskeletal dynamics.18
LC-MS/MS: A sensitive and selective analytical technique to detect COVID-19 protein biomarkers in the early disease stage
Published in Expert Review of Proteomics, 2023
Siva Nageswara Rao Gajula, Ankita Sahebrao Khairnar, Pallavi Jock, Nikita Kumari, Kendre Pratima, Vijay Munjal, Pavan Kalan, Rajesh Sonti
Muñoz-Prieto et al. analyzed saliva samples from 19 asymptomatic, 16 symptomatic patients with SARS-CoV-2 infection and 20 controls using LC-MS/MS for untargeted peptidomics and proteomic (trypsin digestion of filter retained proteins) profiling [81]. Peptides from 53 salivary proteins are identified. Only controls had Actin-depolymerizing factor (ADF), whereas infected individuals had Interleukin 1 receptor antagonist (IL1RA). In asymptomatic and symptomatic participants, Basic salivary proline-rich proteins (PRPs), Desmocollin-2 (DSC2), Fatty acid binding protein 5 (FABP5), Histatin 1 (his-1), IL1RA, Salivary acidic proline rich phosphoprotein ½ (PRH1), Statherin (STATH), Submaxillary gland androgen regulated protein 3B (SMR3B), Annexin A1 (ANXA1), Mucin 7 (MUC7), Alpha-actinin-4 (ACTN4), Immunoglobulin kappa variable 1–33 (IGKV1-33) and Protein-glutamine gamma-glutamyltransferase E (TGM3) were significantly different. Out of 117 retained proteins, 11 changed significantly from asymptomatic to symptomatic. The most significant discriminant proteins at Principal component analyses followed by LC-MS/MS-SRM validation were IL1RA, CYSTB, S100A8, S100A9, CA6, and FABP5. For potential biomarkers and therapeutic targets, the differentially abundant proteins implicated in innate immunity (S100 proteins), taste (CA6 and cystatins), and viral binding to the host (FABP5) appear to be of interest.
Chondrocyte protein co-synthesis network analysis links ECM mechanosensing to metabolic adaptation in osteoarthritis
Published in Expert Review of Proteomics, 2021
Aspasia Destouni, Konstantinos C. Tsolis, Anastassios Economou, Ioanna Papathanasiou, Charalampos Balis, Evanthia Mourmoura, Aspasia Tsezou
Indentation-type atomic force microscopy in biopsies from OA patients has revealed that the nano-stiffness of damaged cartilage is lower than the healthy non-degraded cartilage and that OA cartilage becomes softer due to progressive disintegration of the collagen meshwork [68]. The observed depletion of ECM and PCM structural components and the concurrent upregulation of CD44, a sensor of ECM integrity indicate a shift toward a low ECM adhesion microenvironment in OA [69]. In low ECM adhesion conditions, integrin signaling has been shown to be dampened and integrin-anchored actin filaments become shorter and fragmented [70]. We observed that key structural components of integrin activation and cytoskeleton remodeling such as, TLN, vinculin (VCL), Rho family GTPases RhoA and Rac1, as well as structural components of F-actin stress fibers and focal adhesions, actinin-α isoform 1 (ACTN1) cluster in the core chondrocyte network (Figure 3a). ACTN1 was found abundant in healthy and depleted in hypertrophic OA chondrocytes, whereas F-actin depolymerizing destrin (DSTN) was abundant in OA chondrocytes (Figure 3a) indicating increased actin remodeling in OA. Although the integrin activator and linker to actin filaments TLN1 is more abundant in OA, VCL which stabilizes the interaction between TLN and the actin cytoskeleton under high tension conditions was depleted in OA chondrocytes. These interactions indicate an adaptation of the ECM-focal adhesion interface to low ECM forces.
Related Knowledge Centers
- Actin
- Alpha Helix
- Beta Sheet
- Eukaryote
- Microfilament
- Protein
- Gene
- Adf/Cofilin Family
- Nuclear Magnetic Resonance Spectroscopy of Proteins
- Gelsolin