Traditional Chinese Herbal Medicine for Allergic Diseases: A Review.

The prevalence of allergic disorders has increased in recent years, lowering patients' quality of life and increasing the demand for drugs to treat these diseases. Western drugs such as glucocorticoids, antihistamines, and leukotrienes are routinely utilized in clinics. However, drawbacks like high recurrence rates and adverse effects limit their use. As one of the most promising natural medicine systems, traditional Chinese medicine offers distinct benefits in treating allergic illnesses, such as maintaining long-term treatment, preventing disease recurrence, and producing fewer adverse reactions. We analyzed and discussed recent developments in traditional Chinese medicine used in allergic diseases from three perspectives: Chinese herbal formula, Chinese patent medicine, and active ingredients of traditional Chinese medicine, and explained their main components, efficacy, and mechanisms of action. We also reviewed the modification of Chinese herbal formulas and the combined application of Chinese medicine with Western medicine or nonpharmaceutical therapies. Traditional Chinese medicines are becoming increasingly important in treating allergic disorders. Improving traditional Chinese herbal formulas and developing safe and effective Chinese patent medicines are currently the most pressing and important aspects of research on traditional Chinese medicine.

Negative effects of retinoic acid on stem cell niche of mouse incisor.

The continuous growth of mouse incisors depends on epithelial stem cells (SCs) residing in the SC niche, called labial cervical loop (LaCL). The homeostasis of the SCs is subtly regulated by complex signaling networks. In this study, we focus on retinoic acid (RA), a derivative of Vitamin A and a known pivotal signaling molecule in controlling the functions of stem cells (SCs). We analyzed the expression profiles of several key molecules of the RA signaling pathway in cultured incisor explants upon exogenous RA treatment. The expression patterns of these molecules suggested a negative feedback regulation of RA signaling in the developing incisor. We demonstrated that exogenous RA had negative effects on incisor SCs and that this was accompanied by downregulation of Fgf10, a mesenchymally expressed SC survival factor in the mouse incisor. Supplement of Fgf10 in incisor cultures completely blocked RA effects by antagonizing apoptosis and increasing proliferation in LaCL epithelial SCs. In addition, Fgf10 obviously antagonized RA-induced downregulation of the SC marker Sox2 in incisor epithelial SCs. Our findings suggest that the negative effects of RA on incisor SCs result from inhibition of mesenchymal Fgf10.

Biphasic effect of citral, a flavoring and scenting agent, on spatial learning and memory in rats.

Although some central effects of citral have been reported, cognitive effects on spatial memory have not been investigated. The evidence showed that citral can regulate the synthesis of retinoic acid (RA), which exerts a vital function in the development and maintenance of spatial memory. In this study, we applied Morris water maze to test the effect of citral on animals' spatial learning and memory. To elucidate the mechanism of this effect, we also measured the retinoic acid concentration in rats' hippocampus by high performance liquid chromatography (HPLC). Our data implied biphasic effects of citral. The low dose (0.1 mg/kg) of citral improved the spatial learning capability, and enhanced the spatial reference memory of rats, whereas the high dose (1.0 mg/kg) was like to produce the opposite effects. Meanwhile, the low dose of citral increased the hippocampal retinoic acid concentration, while the high dose decreased it. Due to the quick elimination and non-bioaccumulation in the body, effects of citral on spatial memory in this study seemed to be indirect actions. The change in hippocampal retinoic acid concentration induced by different doses of citral might be responsible for the biphasic effect of citral on spatial learning and memory.

[Effects of Angelica sinensis polysaccharides on hepatic drug metabolism enzymes activities in mice].

OBJECTIVE: To study the effects of Angelica sinensis Polysaccharides (ASP) on the hepatic drug metabolism enzymes activities in normal mice and those prednisolone (PSL)-induced liver injury. METHOD: The activities of phase II enzymes (GSH-related enzymes) and cytochrome P450 enzymes were measured by biochemical method. RESULT: ASP increased the activities of glutathione S-transferase in liver microsomes and mitochondria. The cytochrome P450 content, NADPH-cytochrome c reductase, aminopyrine N-demethylase, and aniline hydroxylase activities in liver microsomes were also increased. PSL significantly increased serum ALT levels, and decreased the liver mitochondrial glutathione content. At the same time, other enzymes activities were all increased. When mice were treated with ASP 2.0 g.kg-1, the PSL-induced changes on cytochrome P450 enzymes, glutathione S-transferase, and GSH content were restored. CONCLUSION: ASP can modulate the activities of drug metabolism enzymes.