Anti-Cancer Potential of Afzelin towards AGS Gastric Cancer Cells

Bioactive Compounds from Kalanchoe Genus Potentially Useful for the Development of New Drugs

The genus Kalanchoe Adans. (Crassulaceae) is native to Madagascar and comprises 145 species, being naturalized in the tropics and cultivated worldwide. In addition to having ornamental value, several Kalanchoe species are commonly used in popular medicine for the treatment of inflammatory conditions, wounds, gastric ulcers, and other diseases. The great importance of the genus is reflected on its acknowledgment by traditional and alternative health systems and organizations, as well as on the growing number of papers reporting pharmacological properties of extracts and isolated compounds from Kalanchoe. Among these properties, we highlight anti-inflammatory, antitumor, wound healing, antiulcer, and muscle relaxing properties. These activities are attributed mostly to flavonoids and bufadienolides, the main secondary metabolites reported in Kalanchoe extracts. While bufadienolides are generally related to cytotoxic and muscle relaxing activities, flavonoids are commonly reported as anti-inflammatory and wound healing agents. This review provides up to date information and perspectives on bioactive compounds from the Kalanchoe genus that are potentially useful for the development of new drugs. It includes not only a discussion on the advantages of the Kalanchoe species as source of bioactive compounds, but also the gaps, opportunities, and challenges to translate the acquired knowledge into innovation for drug development.

Traditional uses, phytochemistry, pharmacology, and toxicity of Eriobotrya japonica leaves: A summary

ETHNOPHARMACOLOGICAL RELEVANCE

Eriobotrya japonica Lindl. has been included in "The Plant List" (http://www.theplantlist.org) and is the most widely researched species in its genus. E. japonica is a subtropical evergreen fruit tree belonging to the Rosaceae family. Its dried leaves are widely used in traditional Chinese herbal medicine to treat coughing caused by pulmonary inflammation, dyspnea due to asthma and cough, nausea caused by stomach disorders, restlessness, and thirst. Furthermore, it is used to treat stomach ache, ulcers, chronic bronchitis, cancer, and diabetes mellitus in Japanese folk medicine. However, no systematic reports on E. japonica leaves have been published before.

AIM OF THE STUDY

This review summarizes the available information on the traditional uses, phytochemistry, pharmacology, toxicity, and quality control of various extracts and phytoconstituents of E. japonica leaves.

MATERIALS AND METHODS

Relevant publications between 1931 and 2022 were considered. Chinese and English studies on E. japonica leaves were collected from databases, including PubMed, Web of Science, Elsevier, ACS Publications, Springer, and CNKI (Chinese). The traditional uses, phytochemistry, pharmacology, toxicity, and quality control of E. japonica leaves were reviewed.

RESULTS

Briefly, 164 compounds, including triterpenes, flavonoids, sesquiterpene glycosides, megastigmane derivatives, phenylpropanoids, and organic acids, have been identified from E. japonica leaves, in addition to 169 volatile oils. More than half of these compounds have not yet been reported to have pharmacological activities. Triterpenes and flavonoids are the most important bioactive compounds responsible for pharmacological activities, such as antidiabetic, anti-inflammatory, and antitumor activities. Other beneficial physiological effects such as antioxidant, hepatoprotective, bronchodilatory, antitussive, and expectorant effects and tracheal smooth muscle relaxation, protection against myocardial ischemia injury, and improved cognitive activities have also been reported. High doses of E. japonica leaf extracts have been used in laboratory animals, and no side effects or toxicity-symptoms have been observed.

CONCLUSIONS

The pharmacological activities of E. japonica leaves support their use in traditional Chinese herbal medicine. However, several aspects, such as the bioavailability, pharmacodynamics, pharmacokinetics, mechanism of action, and structure-activity relationships of the pure compounds isolated from E. japonica leaves, have not been studied yet and warrant further studies.

A Review of the Phytochemistry and Pharmacology of the Fruit of Siraitia grosvenorii (Swingle): A Traditional Chinese Medicinal Food

Siraitia grosvenorii (Swingle) C. Jeffrey ex Lu et Z. Y. Zhang is a unique economic and medicinal plant of Cucurbitaceae in Southern China. For hundreds of years, Chinese people have used the fruit of S. grosvenorii as an excellent natural sweetener and traditional medicine for lung congestion, sore throat, and constipation. It is one of the first species in China to be classified as a medicinal food homology, which has received considerable attention as a natural product with high development potential. Various natural products, such as triterpenoids, flavonoids, amino acids, and lignans, have been released from this plant by previous phytochemical studies. Phar- macological research of the fruits of S. grosvenorii has attracted extensive attention, and an increasing number of extracts and compounds have been demonstrated to have antitussive, expectorant, antiasthmatic, antioxidant, hypoglycemic, immunologic, hepatoprotective, antibacte- rial, and other activities. In this review, based on a large number of previous studies, we summarized the related research progress of the chemical components and pharmacological effects of S. grosvenorii, which provides theoretical support for further investigation of its biological functions and potential clinical applications.

p-Coumaric acid, Kaempferol, Astragalin and Tiliroside Influence the Expression of Glycoforms in AGS Gastric Cancer Cells

Abnormal glycosylation of cancer cells is considered a key factor of carcinogenesis related to growth, proliferation, migration and invasion of tumor cells. Many plant-based polyphenolic compounds reveal potential anti-cancer properties effecting cellular signaling systems. Herein, we assessed the effects of phenolic acid, p-coumaric acid and flavonoids such as kaempferol, astragalin or tiliroside on expression of selected cancer-related glycoforms and enzymes involved in their formation in AGS gastric cancer cells. The cells were treated with 80 and 160 µM of the compounds. RT-PCR, Western blotting and ELISA tests were performed to determine the influence of polyphenolics on analyzed factors. All the examined compounds inhibited the expression of MUC1, ST6GalNAcT2 and FUT4 mRNAs. C1GalT1, St3Gal-IV and FUT4 proteins as well as MUC1 domain, Tn and sialyl T antigen detected in cell lysates were also lowered. Both concentrations of kaempferol, astragalin and tiliroside also suppressed ppGalNAcT2 and C1GalT1 mRNAs. MUC1 cytoplasmic domain, sialyl Tn, T antigens in cell lysates and sialyl T in culture medium were inhibited only by kaempferol and tiliroside. Nuclear factor NF-κB mRNA expression decreased after treatment with both concentrations of kaempferol, astragalin and tiliroside. NF-κB protein expression was inhibited by kaempferol and tiliroside. The results indicate the rationality of application of examined polyphenolics as potential preventive agents against gastric cancer development.

Kaempferol 3-Rhamnoside on Glutamate Release from Rat Cerebrocortical Nerve Terminals Involves P/Q-Type Ca2+ Channel and Ca2+/Calmodulin-Dependent Protein Kinase II-Dependent Pathway Suppression

Excess synaptic glutamate release has pathological consequences, and the inhibition of glutamate release is crucial for neuroprotection. Kaempferol 3-rhamnoside (KR) is a flavonoid isolated from Schima superba with neuroprotective properties, and its effecton the release of glutamate from rat cerebrocortical nerve terminals was investigated. KR produced a concentration-dependent inhibition of 4-aminopyridine (4-AP)-evoked glutamate release with half-maximal inhibitory concentration value of 17 µM. The inhibition of glutamate release by KR was completely abolished by the omission of external Ca²⁺ or the depletion of glutamate in synaptic vesicles, and it was unaffected by blocking carrier-mediated release. In addition, KR reduced the 4-AP-evoked increase in Ca²⁺ concentration, while it did not affect 4-AP-evoked membrane potential depolarization. The application of selective antagonists of voltage-dependent Ca²⁺ channels revealed that the KR-mediated inhibition of glutamate release involved the suppression of P/Q-type Ca²⁺ channel activity. Furthermore, the inhibition of release was abolished by the calmodulin antagonist, W7, and Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) inhibitor, KN62, but not by the protein kinase A (PKA) inhibitor, H89, or the protein kinase C (PKC) inhibitor, GF109203X. We also found that KR reduced the 4-AP-induced increase in phosphorylation of CaMKII and its substrate synapsin I. Thus, the effect of KR on evoked glutamate release is likely linked to a decrease in P/Q-type Ca²⁺ channel activity, as well as to the consequent reduction in the CaMKII/synapsin I pathway.