Medicinal Plants Classification Biosynthesis and ... - Index of

110
Aracely E. Chávez-Piña and Andrés Navarrete
Gastroprotective Mechanism
Mediator Response
Functional factors
Mucus-bicarbonate-phospholipid ―barrier‖
Mucosal microcirculation
Humoral factors
Prostaglandins (PGs)
Preserve mucosal integrity by preventing the entry of
foreign particles of pathogens
Delivery of oxygen and nutrients and removal of
toxic substances from the mucosa
Maintenance of gastric blood flow by PGI 2 and
bicarbonate and mucus secretion by PGE 2 Inhibition
of leukocyte adherence and the increment on
epithelial proliferation by PGs-derived from COX-2
Nitric oxide (NO) Regulation of gastric mucosa blood flow, acid,
alkaline and mucus secretion. Inhibition of leukocyte
adherence
Lipoxins Suppress aspirin-induced leukocyte adherence within
the gastric microcirculation.
Inhibiton of LTB 4 responses in neutrophils
Down-regulates CD11b/CD18, and reduction of
leukocyte adhesion to the endothelium
Increment of nitric oxide synthesis
Increment of mucosal blood flow
Hydrogen sulfide (H 2 S) Inhibition of leukocyte adherence
Reduction in the expression of proinflammatories
cytokines such as TNF-α
Increment of mucosal blood flow
Neuronal factors
Calcitonin gen receptor peptide (CGRP)
Other gastroprotective factors
Cytokines
Induction of NO synthesis and increment on gastric
blood flow
IL-1β inhibits migration of neutrophils and
leukotriene B 4
Inhibition in the release of platelet-activating factor
Annexin-1 Promotion of leukocyte detachment, and inhibition of
cell extravasation
Role on gastric ulcer healing
Activation of the same receptor than lipoxin A 4
Proteinase-activated receptors (PAR) PAR-2 triggers cytoprotective secretion of gastric
mucus by stimulating the release of CGRP
PAR-1 releases VEGF and inhibits release of
endostatin
3.3.5. TNF-
Tumour necrosis factor α is expressed after NSAID and ethanol administration, and it has
been related with their adverse effects [4, 7, 15]. This event is a stimulus for the expression of