Neuroinflammatory reactions in experimental gastric ulcer: Target for mucosal protection

Cytoprotective gastric pentadecapeptide BPC 157 resolves major vessel occlusion disturbances, ischemia-reperfusion injury following Pringle maneuver, and Budd-Chiari syndrome

The stable gastric pentadecapeptide BPC 157 counteracts various venous occlusion-induced syndromes. Summarized are all these arguments, in the Robert’s cytoprotection concept, to substantiate the resolution of different major vessel occlusion disturbances, in particular ischemia-reperfusion injury following the Pringle maneuver and Budd-Chiari syndrome, which was obtained by BPC 157 therapy. Conceptually, there is a new point, namely, endothelium maintenance to epithelium maintenance (the recruitment of collateral blood vessels to compensate for vessel occlusion and reestablish blood flow or bypass the occluded or ruptured vessel). In this paper, we summarize the evidence of the native cytoprotective gastric pentadecapeptide BPC 157, which is stable in the human gastric juice, is a membrane stabilizer and counteracts gut-leaky syndrome. As a particular target, it is distinctive from the standard peptide growth factors, involving particular molecular pathways and controlling VEGF and NO pathways. In the early 1990s, BPC 157 appeared as a late outbreak of the Robert’s and Szabo’s cytoprotection-organoprotection concept, like the previous theoretical/practical breakthrough in the 1980s and the brain-gut axis and gut-brain axis. As the time went on, with its reported effects, it is likely most useful theory practical implementation and justification. Meantime, several reviews suggest that BPC 157, which does not have a lethal dose, has profound cytoprotective activity, used to be demonstrated in ulcerative colitis and multiple sclerosis trials. Likely, it may bring the theory to practical application, starting with the initial argument, no degradation in human gastric juice for more than 24 h, and thereby, the therapeutic effectiveness (including via a therapeutic per-oral regimen) and pleiotropic beneficial effects.

Intracerebroventricular injection of clonidine releases beta-endorphin to induce mucosal protection in the rat

The possibility that the endogenous opioid system could be involved in the central nervous system (CNS)-mediated gastroprotective effect of clonidine was investigated. Intracerebroventricularly (i.c.v.) injected clonidine (470 pmol/rat) inhibited the gastric mucosal lesions induced by (orally administered) acidified ethanol in a significant manner in the rat. The gastroprotective effect of the centrally administered clonidine was antagonised by i.c.v. or intracisternally (i.c.) administered presynaptic alpha-2 adrenoceptor antagonist, yohimbine; the non-selective opioid receptor antagonist, naloxone; and the delta opioid receptor antagonist naltrindole. These results suggest that an interaction between central alpha-2 adrenoceptors and endogenous opioid systems is involved in mediating the mucosal protective effect. beta-endorphin antiserum (i.c.) also antagonised the gastroprotection induced by intracerebroventricularly injected clonidine indicating that beta-endorphin release is likely to be a key factor in the gastroprotective effect of clonidine. Furthermore, the i.c.v. or i.c. injection of beta-endorphin produced a potent gastroprotection in the picomolar range. The mucosal protective effect of clonidine was abolished after vagotomy indicating that the central effect may be conveyed to the periphery by vagal efferents. Since atropine (1 mg/kg i.v.) failed to modify, but hexamethonium (10 mg/kg i.v.) antagonised the gastroprotective effect of clonidine, it would appear that in the periphery nicotinic, but not muscarinic, cholinergic receptors are likely to be involved in the mucosal protective effect of clonidine. In conclusion, clonidine (i.c.v.) induces gastroprotective action by releasing an endogenous opioid substance - most likely beta-endorphin - in the rat. The clonidine-induced central gastroprotection requires the integrity of vagal pathway; cholinergic nicotinic - but not muscarinic - receptors might mediate the effect in the periphery.