Inhibitions of platelet-activating factor production and granulocyte oxidative activation by Rikkunshi-To in the process of gastric mucosal injury

Kampo medicines Rikkunshito and Hangeshashinto prevent cisplatin-induced intestinal mucosal injury in rats

BACKGROUND/PURPOSE

We examined the effects and mechanisms of rikkunshito (RKT) and hangeshashinto (HST) on cisplatin-induced mucosal injuries in the rat small bowel.

METHODS

Juvenile rats were divided into 6 groups: sham control, cisplatin injection without kampo medicines, and cisplatin injection with oral administration of low and high doses of RKT (1000 mg/kg and 2000 mg/kg) and HST (500 mg/kg and 1000 mg/kg). Fecal condition, intestinal morphological changes, enterocyte proliferation, and enterocyte apoptosis were assessed.

RESULTS

Diarrhea and atrophy of ileal villi observed in the cisplatin group were significantly improved in all kampo groups. Injury scores of the jejunum were significantly lower with RKT (2000 mg/kg) and HST (500 and 1000 mg/kg) than with cisplatin, and those of the ileum were significantly lower with HST (500 and 1000 mg/kg) than with cisplatin. Enterocyte proliferation of the jejunum was significantly increased with RKT (2000 mg/kg) and HST (500 mg/kg) compared with cisplatin, and those of the ileum were significantly increased in all kampo groups compared with the cisplatin group. Jejunal and ileal apoptosis following cisplatin administration was significantly inhibited by HST.

CONCLUSIONS

RKT and HST prevented cisplatin-induced intestinal mucosal injury with increasing proliferation of intestinal epithelial cells. HST also attenuated cisplatin-induced crypt cell apoptosis.

Beneficial effects of rikkunshito, a Japanese kampo medicine, on gastrointestinal dysfunction and anorexia in combination with Western drug: a systematic review

Background. Kampo medicines are traditional herbal medicines which have been approved for medicinal use by the Japanese Ministry of Health and Welfare and are currently being used more and more, often in combination with Western drugs. Thus, the need for investigation of interactions between Kampo medicines and Western drugs is now widely recognized. Aim. To summarize the effects and drug interactions of rikkunshito, a Kampo medicine often prescribed for upper gastrointestinal disorders and anorexia. Methods. Animal and human studies were systematically reviewed to identify published data on rikkunshito. Results describing its effects were abstracted, with an emphasis on drug interactions. Results and Discussion. Rikkunshito ameliorates anorexia induced by anticancer drugs, improves quality of life scores, and can even prolong survival compared with monotherapy. Rikkunshito combined with proton pump inhibitor therapy is shown to be useful in the treatment of PPI-refractory gastroesophageal reflux disease patients and patients with gastrointestinal symptoms after endoscopic submucosal dissection. Rikkunshito reduces antidepressant-induced adverse events and improves quality of life without influencing antidepressant effects. Conclusions. Rikkunshito shows ameliorative effects on adverse reactions induced by various Western drugs and can achieve better results (e.g., anticancer drugs and proton pump inhibitor) without influencing the efficacy and bioavailability of Western drugs.

Intragastric infusion of rikkunshito (kampo) induces proximal stomach relaxation in conscious dogs

PURPOSE

Abnormal proximal gastric relaxation is one of the causes of functional dyspepsia. The purpose of this study is to use a barostat in conscious dogs to determine the effects of rikkunshito, which is considered to have beneficial effects on functional dyspepsia, on the proximal stomach.

METHODS

Eight beagles were used. A gastrocutaneous fistula and force transducers were surgically implanted in the middle corpus and gastric antrum and duodenum, respectively. After a recovery period, a plastic bag was inserted through the gastrocutaneous fistula and the proximal stomach was distended using a barostat. First, four dogs were used to investigate the pressure-volume relation in the fasted and postprandial phases. Second, the stomachs of four different dogs were continuously distended at minimal distending pressure +2 mmHg, and 5 min later were infused with warmed liquid rikkunshito (2 g/20 mL) or water through the gastrocutaneous fistula. Finally, changes in the proximal gastric volume and gastrointestinal motility were observed.

RESULTS

The proximal stomach was significantly more pliable in the postprandial phase than in the fasted phase. The proximal gastric volume increased immediately after liquid infusion under constant pressure in both phases and duodenal motility was accelerated. The effect of rikkunshito was significantly greater and lasted longer than that of water. No significant difference between the effects during the fasted or postprandial phase and no change in the gastric antrum motility were observed when rikkunshito was infused.

CONCLUSION

These results indicate that rikkunshito accelerates duodenal motility and relaxes the proximal stomach.

Japanese herbal medicine in functional gastrointestinal disorders

Management of functional gastrointestinal disorders is hindered by both poor efficacy and adverse effects of traditional pharmacological therapy. Herbal medicine may be an attractive alternative based on the perception of its 'natural' approach and low risk of side effects; however, the lack of standardization of drug components has limited the ability to perform rigorous clinical studies in Western countries. Japanese herbal medicine (JHM) is a standardized form of herbal medicine with regards to the quality and quantities of ingredients. While extensively studied and widely used in Asia, there is a paucity of data upon which physicians in other parts of the world may draw conclusions regarding the effectiveness of herbal medicine for gastrointestinal disorders. The aim of this study was to summarize the most recent developments in JHM for treatment of functional gastrointestinal disorders. Animal and human studies were systematically reviewed to identify published data of JHM used for treatment of gastrointestinal disorders. The herbal components of JHM were examined. Results describing the physiological and clinical effects of JHM were abstracted, with an emphasis on functional gastrointestinal disorders. JHM are associated with a variety of beneficial physiological on the gastrointestinal system. Patient-based clinical outcomes are improved in several conditions. Rikkunnshi-to reduces symptoms and reverses physiological abnormalities associated with functional dyspepsia, while dai-kenchu-to improves symptoms of postoperative ileus and constipation in children. This updated summary of JHM in the field of gastrointestinal disorders illustrates the potential for herbal medication to serve a valuable role in the management of patients with functional gastrointestinal disorders.

Rikkunshi-to raises levels of somatostatin and gastrin in human plasma

Rikkunshi-to, a traditional Chinese (Kampo) medicine, has been used to treat chronic hypofunctions of the gastrointestinal tract. The effects of Rikkunshi-to on the plasma levels of gut-regulated peptide (somatostatin, motilin, gastrin, and vasoactive intestinal peptide (VIP)) levels were studied in healthy subjects. A single oral administration of Rikkunshi-to caused significant increases in plasma somatostatin and gastrin levels at 60 to 240 min compared with a placebo group. On the other hand, this medicine showed no effects on motilin and VIP levels. In conclusion, these results might indicate that the pharmacological action of Rikkunshi-to is closely related to changes in somatostatin- and gastrin-immunoreactive substance levels.