Aim Goreisan (GRS) is a Japanese Kampo medicine, which has been clinically used to treat edema and headache. Recently, a clinical study indicated that GRS significantly suppresses the recurrence of chronic subdural hematoma (CSDH). In CSDH, leakage from immature blood vessels on the neomembrane is involved in the recurrence or exacerbation. Although several clinical reports have shown the effectiveness of GRS, the pharmacological properties and underlining mechanism of GRS are not clear. In this study, we examined the effect of GRS on the migration and proliferation of vascular endothelial cells via in vitro and in vivo experiments. Method Human umbilical vascular endothelial cells (HUVECs) were treated with vascular endothelial growth factor (VEGF) for 24 h, and migration ability, extracellular signal‐regulated kinase (ERK) phosphorylation level, and aquaporin‐1 (AQP1) expression level were measured. Matrigel containing VEGF was injected subcutaneously into the abdomen of C57BL mice (Matrigel plug assay). After oral administration of GRS for seven days, the effect on angiogenesis was examined by immunostaining. Results GRS inhibited VEGF‐induced migration in a dose‐dependent manner. GRS also inhibited VEGF‐induced phosphorylation of ERK, which is a major signaling molecule for the migration. In addition, GRS markedly decreased protein and mRNA expression of AQP1, which is another important regulator of endothelial cell migration. Finally, GRS inhibited angiogenesis, as revealed by in vivo Matrigel plug assay. Conclusion The findings indicated that GRS can suppress angiogenesis through inhibiting the migration of endothelial cells by downregulating ERK activation and aquaporin‐1 expression, leading to the preventive effect of GRS against CSDH recurrence.

Aim Goreisan (GRS) is often used for gastrointestinal symptoms associated with bacterial and viral infections, to cure diarrhea and to prevent general dehydration. Although several clinical reports have shown the effectiveness of GRS, the pharmacological properties and underlining mechanism of GRS have not been clarified. Methods Lipopolysaccharide (LPS, 10 mg/kg, i.p.) was administered to ICR mice and the diarrhea score was measured every 15 min. Goreisan (GRS; 1 g/kg) was administered 30 min before LPS administration, and the tissues were collected 90 min later. Caco‐2 cells were treated with tumor necrosis factor‐α (TNF‐α, 10 ng/mL) and GRS (0.1 mg/mL) for 24 h, and the aquaporin‐3 (AQP3) expression level was examined by qPCR. Results In this in vivo study, GRS did not affect cytokine production, but markedly improved tissue injury and diarrhea scores. On the other hand, AQP3 mRNA and protein expression in the intestinal epithelium in the LPS‐treated group were significantly reduced, and GRS inhibited this decrease in AQP3. In a similar experiment performed on AQP3‐deficient mice, the diarrhea‐improving and tissue‐improving effects of GRS disappeared. Furthermore, in this in vitro study, GRS suppressed the decrease in AQP3 expression by TNF‐a stimulation, and the mechanism was due to extracellular signal‐regulated kinase (ERK) inhibition. Conclusion GRS has both an antidiarrhea effect and an intestinal tissue‐protective effect, which it exerts through the inhibition of an inflammation‐induced decrease in intestinal AQP3 expression. Our data strongly support the clinical usefulness of GRS to prevent dehydration in infectious gastroenteritis as well as the pharmacological rationale for using GRS to treat this disease.

AimIn Japan, goreisan (GRS) is used to alleviate cerebral edema and relieve headaches. Although improvement of water maldistribution in the brain may be one of the mechanisms of action of GRS for cerebral edema and headache, scientific evidence is limited. Here, we aimed to investigate the action mechanism of GRS against cerebral edema and headaches, focusing on water dynamics in the brain.MethodsWe used a well‐established mouse model of cerebral edema to evaluate the effects of GRS on related symptoms and brain water content. The mouse model was subjected to magnetic resonance imaging (MRI) using H217O to assess water dynamics in the brain. The effect of GRS on water permeability through aquaporin‐4 (AQP4) was also examined in vitro.ResultsGRS inhibited the loss of righting reflex and improved survival in the mouse model by ameliorating the increase in brain water content. The MRI evaluation of water dynamics suggested that GRS inhibited water influx into the brain. Evaluation of water permeability via AQP4 in Xenopus laevis oocytes and HEK293 cells showed that GRS inhibited AQP4 function.ConclusionGRS suppressed the ubiquity of water in the brain in a mouse model of cerebral edema, suggesting inhibition of AQP4 function (not AQP4 expression) as one of the action mechanisms of GRS. Our findings provide fundamental evidence for the clinical efficacy of GRS against cerebral edema and headaches.

Goreisan is often used for gastrointestinal symptoms associated with bacterial and viral infections, to care diarrhea and to prevent general dehydration. Although several clinical reports have shown the effectiveness of Goreisan, pharmacological properties and underlining mechanism of Goreisan has not been clear. In this study, therefore, we investigated the antidiarrheic effect of Goreisan using a mouse model of enterocolitis induced by Lipopolysaccharide (LPS). Goreisan did not affect TNF-α mRNA expression, but markedly improved tissue injury and diarrhea scores. On the other hand, aquaporin-3 (AQP3) is expressed in the intestinal epithelium, and responsible for the absorption of water in the intestinal tract. Interestingly, both AQP3 mRNA and protein expression in the intestinal epithelium in LPS-treated group were significantly reduced, and Goreisan inhibited this decrease in AQP3. Decrease in AQP3 is thought to be associated with development of diarrhea, and therefore, Goreisan is estimated to have improved diarrhea symptoms by regulating the expression of AQP3. These results confirmed the effectiveness of Goreisan for infectious gastroenteritis, and it is also suggested a new effect of Goreisan.

BackgroundLow atmospheric pressure triggers weather-related illnesses, such as headaches. Although many individuals are affected by weather-related illnesses, only a few therapeutic drugs are available. In Japan, goreisan (GRS) is traditionally used to relieve headaches; however, its mechanism of action is unclear. Therefore, we investigated the mechanism of action of GRS against headaches, focusing on water dynamics.MethodsWe used a well-established mouse model of cerebral oedema to evaluate the effects of GRS on related symptoms and brain water content. The mouse model was subjected to magnetic resonance imaging (MRI) using 17O-labelled water (H217O) to assess water dynamics in the brain. The effect of GRS on water permeability through aquaporin 4 (AQP4) was examined in vitro to elucidate its mechanism of action.ResultsGRS inhibited the loss of righting reflex and survival in the mouse model by ameliorating the increase in brain water content. In the same mouse model, MRI evaluation of water dynamics using H217O-derived signal changes showed that GRS reduced the maximum signal intensity change in the cortex and the areas under the curve in the cortex and lateral ventricle. Evaluation of water permeability in Xenopus laevis oocytes expressing AQP4 showed that GRS inhibited water permeability by suppressing AQP4 function. ConclusionsGRS inhibits cerebral oedema and related symptoms partly by inhibiting AQP4 water permeability. These findings provide insights into the alleviating effects of GRS on headaches caused by cerebral oedema. This study could serve as a basis to develop novel therapeutic agents for treating weather-related illnesses.