Medicinal Plants Classification Biosynthesis and ... - Index of

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Aracely E. Chávez-Piña and Andrés Navarrete
1. Introduction
Gastric injury is present in people from both development and undeveloped countries.
Stress and ingestion of irritants such as caffeine, alcohol, nicotine, and drugs like NSAIDs
cause it and also highly spicy food. Endogenous irritants may induce also certain injury at the
mucosa levels, for example acid, bile and pepsin.
In the searching for the best treatment against gastric damage, researches have found
several mechanism of how this injury is induced. The understanding of how gastric injury
occurs has helped to the development of new therapies. Many inflammatory mediators play
an important role in gastric mucosa safety.
Drug treatment of peptic ulcer is targeted at either counteracting the aggressive factors or
stimulating the mucosal defense. In spite of the progress in conventional chemistry and
pharmacology in producing effective drugs, the plant kingdom might provide a useful source
of new anti-ulcer compounds for development as pharmaceutical entities or, alternatively, as
simple dietary adjuncts to existing therapies.
Natural products are a significant source of compounds with gastroprotective properties.
Between them, stand out the triterpenes, who have showed this property, and for which the
gastroprotective mechanism has been elucidated in certain way.
In this chapter is outlined the research performed on the properties, pharmacological
mechanisms and chemical features of triterpenes with gastroprotective properties.
2.1. Definition
2. Peptic Ulcer
An ulcer is the disruption of the mucosal integrity of the stomach or duodenum leading to
a local defect or excavation due to active inflammation [1]. Peptic ulcer is a chronic lesion in
any portion of the gastrointestinal (GI) tract. This ulcer is extended throw the muscular layer
of the mucosa to the submucosa or deeper. Duodenum and stomach are the most common
sites on the GI tract were peptic ulcer could appear [2]. In developed countries, 10% of
population develop ulcer at least one moment on their lives. In United States, 4 millions of
people are affected by peptic acid disorders.
For a better understanding of how peptic ulcer is induced, it is necessary the knowledge
of acid secretion and mucosal defense mechanisms.
2.2. Gastric Anatomy
The stomach can be divided into 3 areas (fundus, corpus and antrum). The gastric wall
consists in mucosa, submucosa, muscularis layer and serose. The stomach area, as a gastric
gland is divided in: