Peptic ulcer is a common disorder of the gastrointestinal tract.[19
] Antiulcer drugs are associated with severe side-effects.[20
] Clinical research has confirmed the efficacy of several plants for the treatment of gastroduodenal diseases.[21
] Preliminary phytochemical screening of unripe plantain banana (Musa sapientum
) revealed the presence of primary and secondary metabolites. Screening of active compound using HPTLC revealed the presence of a monomeric flavonoid Leucocyanidin.
Studies by David et al
] reported that Leucocyanidin and its synthetic hydroxyl ethylated and tetra allyl derivatives were found to protect the gastric mucosa from aspirin-induced erosions. Leucocyanidin and its hydroxyl ethylated and tetra allyl derivatives significantly increased mucus thickness.
The mechanism by which indomethacin induces ulcer is by inducing H+
ATPase in gastric parietal cells. This increases the gastric acid secretion and decreases pH in ulcerated rats, whereas esomeprazole, a PPI (proton pump inhibitor) inhibits H+
ATPase in gastric parietal cells.[23
] In our present study the decrease in gastric volume and increase in pH in Musa sapientum
-treated animals might be by inhibiting the Hcl secretion. Amr et al
] in their studies reported that there was significant decrease in gastric volume and increase in pH when the ulcerated rats were treated with Cinnamon and Chamomile in dose-dependent manner. Our results are comparable with their report. The decrease in the level of hemoglobin might be due to internal bleeding in the lesions of the gastrointestinal (GI) tract and increase in the count of WBC might be the function of immune cells against the inflammation in ulcerated rats. In Musa sapientum
-treated animals the results were reversed which might be due to the presence of a flavonoid leucocyanadin, a compound which protects the gastrointestinal mucosa from lesions produced by various drugs like NSAIDs and other ulcerogenic agents, and was in agreement with the results of standard drug esomeprazole. Green unripe plantains have been reported to have an active principle(s) which enhances the formation of red blood cells in addition to the gastro-protective capacity against indomethacin-induced gastric mucosal injury in rats.[25
] David et al
] in their study stated that dried unripe plantain banana powder, leucocyanidin extracted from Musa sapientum
and a purified synthetic leucocyanidin have a protective effect against aspirin-induced erosions. Our results are in agreement with their report.
The decrease in the protein content of the gastric mucosa in the indomethacin administered groups may be due to damage in the gastric mucosa which results, in the leakage of protein into the gastric juice. Treatment with Musa sapientum
increased the mucosal protein which indicates its ability to act at the cellular level in the mucus gland, i.e. it enhances cell proliferation and stimulates the growth of the gastric mucosa. This stimulatory effect of banana on mucosal growth was responsible for the rapid healing of ulcers in rats treated with indomethacin and was congruent with the results of esomeprazole. Musa sapientum
increases mucus resistance to ulcerogenic substances thus enhanced the recovery from ulcers.[10
There was a significant decrease in the levels of glycoproteins, viz. sialic acid and hexosamine, of the gastric mucosa in the ulcerated group of rats when compared to normal groups which might be due to damage in the mucosal layer. On treatment with antiulcer standard drugs (esomeprazole) and Musa sapientum
, there was significant elevation in the level of sialic acid and hexosamine when compared to the ulcer-induced group. The mechanism of action of Musa sapientum
is by stimulating the growth of the gastric mucosa by increasing mucosal protein i.e. sialic acid and hexosamine, which in turn increase the production of mucus and thus prevent erosion by the ulcer. These significant increased levels of sialic acid and hexosamine correlated with the increased mass of mucosa in the stomach of animals treated with banana. The mode of action of the banana appears to be unlike that of conventional anti-ulcerogenic drugs in that it promotes mucus secretion by stimulating the growth of mucosal cells The regenerated mucosa cells would rapidly seal damaged areas with a secretory layer of mucus and prevent further erosions due to gastric HCl and pepsin.[6
The beneficial effect of the administration of dried banana powder might be due to its enhanced mucosal resistance. Musa sapientum
also promotes healing of ulcers by the presence of water-soluble polysaccharides (e.g. Pectin) in unripe plantain banana.[27
The level of NO was significantly elevated in the serum in ulcerated rats when compared to normal rats. Administration of Musa sapientum and antiulcer drugs decreases the level of NO in serum when compared to ulcerated rats. The level of NO in tissue was significantly reduced when compared to normal whereas treatment with Musa sapientum and antiulcer drugs brought the level of NO in tissue to near normal.
Nishida et al
] in their study reported that NO produced by Constitutive Nitric Oxide Synthase (cNOS) is cytoprotective and NO produced by inducible nitric oxide synthase (iNOS) is cytotoxic Tarek et al
] in their study reported that the ulcerated rats exhibited marked reduction in tissue NO, which further adds to the enhanced neutrophil infiltration. It was reported that indomethacin caused up-regulation of endothelin-1[30
] that leads to decreased production of gastric mucosal cNOS. In addition, the neutrophil-derived HOCl was reported to inhibit cytoprotective eNOS.[31
] On the contrary, the study by Tarek et al
] demonstrated that indomethacin produced a marked elevation in serum NO, the observed increase in myeloperoxidase MPO activity may facilitate the increase in serum NO as the MPO/H2
system serves as a major catalytic sink for NO preventing NO feedback inhibition.[32
] Tarek et al
] in their results reported that indomethacin-induced gastric injury might be mediated, at least in part, by the reduction in tissue cNOS-derived NO content and enhanced production of iNOS-derived NO in serum. Our findings concerning NO are in agreement with the widely accepted fact that, in the digestive system, NO produced by cNOS is cytoprotective and NO produced by iNOS is cytotoxic.
The antiulcer property of herbal plants has been studied and reported by many ethanobotanists.[33
] But studies by Ratnasooriya[37
] and Arambewela et al
] reported that even nutraceautical products like black tea and the ginger family have antiulcer property.
Vimal et al
] in their studies with polyherbal drugs with the composition of Asparagus racemosus
Wild (AR), Centella asiatica
Linn (CA). Convolvulus pluricaulis
(CP), Emblica officinalis
(EO), Ocimum sanctum
(OS) and Withania somnifera
Dunal (WS), reported that the polyphenols, flavonoids etc., present in these plants have antiulcer activity. The possible mechanism of antiulcer activity may be by the presence of polyphenols in poly herbal drug which inhibited acetylcholine synthesis. Free radicals are involved in the progression of ulcers. Extract from Cassia auriculata
possesses maximum in vitro
free radical scavenging activity along with an ameliorative effect on various ulcerative parameters.[40
Musa sapientum being a nutraceautical, can be consumed as food rather than as a drug which enhances the satiety value for the patients.