title: Ultrastructure of platelets and fibrin networks of asthmatic mice exposed to selenium and Withania somnifera.
abstract: Platelets and fibrin play an important role in allergic processes, including allergic asthma. The asthmatic BALB/c mouse model was used to induce asthma, and asthmatic mice were treated with the anti-inflammatory plant Withania somnifera, separately and in combination with the antioxidant selenium. Selenium is an important supplement in asthma, because asthmatics may have a selenium deficiency. Hydrocortisone was used as positive control. Results indicate control mice possess major thick fibers, minor thin fibers, and tight round activated platelets with typical pseudopodia formation. Minor fibers of asthmatic mice have a netlike appearance covering the major fibers whereas the platelets form loosely connected, granular aggregates. Hydrocortisone made the fibrin more fragile and platelet morphology changes from a tight activated platelet to a more granular activated platelet, not closely fused to each other. The plant extracts, separately and in combination with selenium did not affect the fragility of the fibrin and reversed the formation of the dense minor netlike layer over the major fibers, and the platelets formed a dense aggregate. Asthmatic mice treated with selenium showed a dense minor fibrin layer; however, the platelets formed a dense aggregate. We conclude that the anti-inflammatory products affect the stability of fibrin networks but not platelet stability (seen with hydrocortisone). Selenium does not affect the stability of the fibrin networks, but affects platelet stability. These results suggests that asthmatic patients should indeed use an antioxidant supplement, e.g. selenium, because it stabilizes activated platelets, together with anti-inflammatory products.
authors.affiliation: Department of Anatomy, University of Pretoria, PO Box 2034, Pretoria, 0001, Gauteng, South Africa. resia.pretorius@up.ac.za
authors.forename: Etheresia
authors.initials: E
authors.lastname: Pretorius
authors.forename: Hester Magdalena
authors.initials: HM
authors.lastname: Oberholzer
authors.forename: Warren A
authors.initials: WA
authors.lastname: Vieira
authors.forename: Eureka
authors.initials: E
authors.lastname: Smit
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology* / Q000627:therapeutic use; D001249:Asthma / Q000188:drug therapy; D001792:Blood Platelets / Q000187:drug effects* / Q000648:ultrastructure; D004359:Drug Therapy, Combination; D005260:Female; D005337:Fibrin / Q000187:drug effects* / Q000648:ultrastructure; D007958:Leukocyte Count; D051379:Mice; D008807:Mice, Inbred BALB C; D008855:Microscopy, Electron, Scanning; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D012643:Selenium / Q000494:pharmacology* / Q000627:therapeutic use; D032341:Withania
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D005337:Fibrin; D012643:Selenium