5-HT1A receptor binding in the dorsal raphe nucleus is implicated in the anxiolytic-like effects of Cinnamomum cassia

Cinnamomum cassia Presl: A Review of Its Traditional Uses, Phytochemistry, Pharmacology and Toxicology

Cinnamomum cassia Presl is a tropical aromatic evergreen tree of the Lauraceae family, commonly used in traditional Chinese medicine. It is also a traditional spice, widely used around the world. This paper summarizes the achievements of modern research on C. cassia, including the traditional uses, phytochemistry, pharmacology and toxicology. In addition, this review also discusses some significant issues and the potential direction of future C. cassia research. More than 160 chemicals have been separated and identified from C. cassia. The main constituents of C. cassia are terpenoids, phenylpropanoids, glycosides, etc. Modern studies have confirmed that C. cassia has a wide range of pharmacological effects, including antitumour, anti-inflammatory and analgesic, anti-diabetic and anti-obesity, antibacterial and antiviral, cardiovascular protective, cytoprotective, neuroprotective, immunoregulatory effects, anti-tyrosinase activity and other effects. However, the modern studies of C. cassia are still not complete and more in-depth investigations need to be conducted in alimentotherapy, health product, toxicity and side effects, and more bioactive components and potential pharmacological effects need to be explored in the future.

Mexican medicinal plants with anxiolytic or antidepressant activity: Focus on preclinical research

ETHNOPHARMACOLOGICAL RELEVANCE

Anxiety and depression are considered the most prevalent psychiatric disorders worldwide. In Mexico, the use of medicinal plants to alleviate the symptoms associated with these psychiatric disorders is increasing. However, there is little scientific evidence that validates the efficacy of these plants. This evidence needs to be critically revised, and further studied to provided scientific support for their use.

AIM OF THE STUDY

To identify the plants that are used in Mexico for the treatment of disorders related to anxiety and depression, and to review the current preclinical and when available, clinical information of these plants.

METHODS

We searched in scientific databases (Pubmed, Web of Science, Scopus and other web sources such as "Biblioteca digital de la medicina tradicional Mexicana" ) for Mexican plants used for the treatment of anxiety and depression that have been analyzed in preclinical studies. Additional information was obtained from published books. For this review, we also consider those plants used in Mexican traditional medicine for the treatment of "nervios," "susto" or "espanto;" common terms that describe symptoms related to anxiety and depression disorders.

RESULTS

The bibliographic search identified 49 plants used in Mexican traditional medicine for the treatment of disorders related to anxiety and depression. From all these plants, 59% were analyzed in preclinical research, and only 8% were tested in clinical studies; only a few of these studies tried to elucidate their mechanism of action. In general, it is proposed that the plant extracts interact with the GABAergic system. However, only part of these studies attempted to analyze other neurotransmitter systems. Finally, in some cases, drug-herbal interactions were reported.

CONCLUSIONS

There is a large number of Mexican medicinal plants used as a treatment for anxiety and depression disorders. Although some of these plants have been studied in preclinical research, in most cases these studies are preliminary, and the understanding of the mechanism of action is inconclusive. The need for systematic studies in preclinical and clinical research is evident, and efforts should be done to fulfill these research. Finally, it is important also to study possible drug-herbal interactions to establish specific recommendations for people that use these plants as anxiolytic or antidepressant treatments either alone or in combination with another type of medicine.