Anti-colitic effects of the modified Bojanggunbi-tang on dextran sulfate sodium-induced mouse colitis model.

Bojanggunbi-tang (BGT) is a well-known and widely used herbal prescription in Korea for colon diseases, with well-documented pharmacological effects on the digestive system. The current study aimed to develop a new simple and effective prescription using the original prescription. mBGT, a modified BGT, was developed by mixing the extracts of Lonicera japonica Thunb., Alisma orientalis and Atractylodes macrocephala based on a literature review and screening of 16 kinds of component herbs of BGT. A colitis mouse (Male, BALB/c) model was induced using dextran sulfate sodium (5%). The effects of BGT and mBGT on body weight, histological damage, clinical score, macroscopic score and colon length were compared. The mechanisms of action were analyzed based on cytokine production in colon tissue. mBGT at 300mg/kg showed similar effectiveness to that of BGT on colon shortening (P<0.01), clinical score (P<0.05), macroscopic score (P<0.01) and histological damage (P<0.01). In addition, mBGT decreased cytokines, including Interleukin 1 beta, tumor necrosis factor alpha and Interleukin 17, in a dose-dependent manner. In conclusion, mBGT could be a substitute prescription for BGT in clinics and a candidate for the development of a new BGT-based therapeutic agent against colitis.

Flavanone glycosides inhibit ß-site amyloid precursor protein cleaving enzyme 1 and cholinesterase and reduce Aß aggregation in the amyloidogenic pathway.

Alzheimer's disease (AD) is a slow but progressive neurodegenerative disease. One of the pathological hallmarks of AD is the progressive accumulation of ß-amyloid (Aß) in the form of senile plaques, and Aß insult to neuronal cells has been identified as one of the major causes of AD onset. In the present study, we investigated the anti-AD potential of four flavonoids, naringenin, didymin, prunin, and poncirin, by evaluating their ability to inhibit acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and ß-site amyloid precursor protein cleaving enzyme 1 (BACE1). All four flavonoids displayed promising inhibitory activity against AChE, BChE, and BACE1. Structure-activity relationships suggested that glycosylation of naringenin at sugar moieties, and at different positions of the glycosidic linkage, might be closely associated with anti-AD potential. Kinetic and docking studies showed the lowest binding energy and highest affinity for the mixed, competitive, and non-competitive type inhibitors didymin, prunin, and poncirin. Hydrophobic interactions and the number of hydrogen bonds determined the strength of the protein-inhibitor interaction. We also examined the neuroprotective mechanisms by which flavonoids act against Aß25-35-induced toxicity in PC12 cells. Exposure of PC12 cells to 10 µM Aß25-35 for 24 h resulted in a significant decrease in cell viability. In addition, pretreatment of PC12 cells with different concentrations of flavonoids for 1 h significantly reversed the effects of Aß. Furthermore, treatment with the most active flavonoid, didymin, significantly reduced BACE1, APPsß, and C99 expression levels in a dose-dependent manner, without affecting amyloid precursor protein (APP) levels in the amyloidogenic pathway. Together, our results indicate that flavonoids, and in particular didymin, exhibit inhibitory activity in vitro, and may be useful in the development of therapeutic modalities for the treatment of AD.