Effects of Granule Dendrobii on chronic atrophic gastritis induced by N-methyl-N'-nitro-N-nitrosoguanidine in rats

Dendrobium officinale is an herb of Traditional Chinese Medicine (TCM) commonly used for treating stomach diseases. One formula of Granule Dendrobii (GD) consists of Dendrobium officinale and American Ginseng (Radix Panacis quinquefolii), and is a potent TCM product in China. Whether treatment with GD can promote gastric acid secretion and alleviate gastric gland atrophy in chronic atrophic gastritis (CAG) requires verification.To determine the effect of GD treatment on CAG and its potential cellular mechanism.A CAG model was induced by feeding rats N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) for 12 wk. After oral administration of low, moderate, and high doses of GD in CAG rats for 8 wk, its effects on body weight, gastric mucosa histology, mucosal atrophy, intestinal metaplasia, immunohistochemical staining of proliferating cell nuclear antigen (PCNA) and B-cell lymphoma-2, and hemoglobin and red blood cells were examined.The body weights of MNNG-induced CAG model rats before treatment (143.5 ± 14.26 g) were significantly lower than that of healthy rats (220.2 ± 31.20 g, P < 0.01). At the 8th week of treatment, the body weights of rats in the low-, moderate-, and high-dose groups of GD (220.1 ± 36.62 g) were significantly higher than those in the untreated group (173.3 ± 28.09 g, all P < 0.01). The level of inflammation in gastric tissue of the high-dose group (1.68 ± 0.54) was significantly reduced (P < 0.01) compared with that of the untreated group (3.00 ± 0.00, P < 0.05). The number and thickness of gastric glands in the high-dose group (31.50 ± 6.07/mm, 306.4 ± 49.32 µm) were significantly higher than those in the untreated group (26.86 ± 6.41/mm, 244.3 ± 51.82 µm, respectively, P < 0.01 and P < 0.05), indicating improved atrophy of gastric mucosa. The areas of intestinal metaplasia were significantly lower in the high-dose group (1.74% ± 1.13%), medium-dose group (1.81% ± 0.66%) and low-dose group (2.36% ± 1.08%) than in the untreated group (3.91% ± 0.96%, all P < 0.01). The expression of PCNA in high-dose group was significantly reduced compared with that in untreated group (P < 0.01). Hemoglobin level in the high-dose group (145.3 ± 5.90 g/L), medium-dose group (139.3 ± 5.71 g/L) and low-dose group (137.5 ± 7.56 g/L) was markedly increased compared with the untreated group (132.1 ± 7.76 g/L; P < 0.01 or P < 0.05).Treatment with GD for 8 wk demonstrate that GD is effective in the treatment of CAG in the MNNG model by improving the histopathology of gastric mucosa, reversing gastric atrophy and intestinal metaplasia, and alleviating gastric inflammation.