Calycopterin

Phytotherapy Research : PTR, 01 Sep 2008, 22(9):1154-1158.

Calycopterin, an immunoinhibitory compound from the extract of Dracocephalum kotschyi.[Reference: WebLink]

Medicinal plants have been widely investigated for their various effects. Dracocephalum kotschyi Boiss (Labiatae) is used in Iranian traditional medicine for the treatment of rheumatoid diseases. The inhibitory effect of D. kotschyi on the lectin-induced cellular immune response has been demonstrated previously.
METHODS AND RESULTS:
In this study, mitogen-treated lymphocytes were exposed to the extract of D. kotschyi and analysed for the induction of apoptosis using flow cytometry and gel electrophoresis. The data obtained indicated a dose-dependent increase of cells in the sub-G1 phase of cell cycle. Study of internucleosomal DNA fragmentation showed a typical DNA laddering in agarose gels. A bioactivity-guided fractionation assay to find the active components responsible for the inhibitory effect of D. kotschyi on mitogen-induced lymphocyte proliferation led to the isolation of Calycopterin from the ethyl acetate extract of D. kotschyi. Its structure was identified by spectroscopic methods including( 1)H-NMR, (13)C-NMR, MS and UV spectra. Calycopterin inhibited lymphocyte proliferation in a dose-dependent manner with an IC(50) value of 1.7 microg/mL.
CONCLUSIONS:
In conclusion, the results of this study suggest that D. kotschyi extract has the capacity to induce apoptosis in the lymphocytes and that isolated Calycopterin is responsible for the inhibitory effect of D. kotschyi on lymphocyte proliferation.

Chemical Research in Toxicology, 2011, 24(12):2280-2292.

Calycopterin Promotes Survival and Outgrowth of Neuron-Like PC12 Cells by Attenuation of Oxidative- and ER-Stress-Induced Apoptosis along with Inflammatory Response.[Reference: WebLink]

There is mounting evidence implicating the role of oxidative stress induced by reactive oxygen species (ROS) in neurodegenerative disease, including Alzheimer's disease.
METHODS AND RESULTS:
Herein we investigated the neuroprotective potential of a natural flavonoid, Calycopterin, against H(2)O(2)-induced cell death in differentiated PC12 cells. We pretreated PC12 cells with 25, 50, and 100 μM Calycopterin followed by the addition of H(2)O(2) as an oxidative stress agent. We measured cell viability by the MTT test and found that 50 μM is the best protective concentration of Calycopterin. Moreover, we measured six different parameters of neurite outgrowth. Interestingly, we found that Calycopterin not only protects PC12 cells against H(2)O(2)-induced apoptosis but also defends against the destructive effect of oxidative stress on the criteria of neural differentiation. Calycopterin decreased ER stress-associated proteins including calpain and caspase-12, and suppressed ERK, JNK, and p38 MAPK phosphorylation. Moreover, Calycopterin inhibited H(2)O(2)-induced nuclear translocation of nuclear factor-κB, a known regulator of a host of genes involved in specific stress and inflammatory responses. This observation was perfectly in agreement with the decrease of COX-2 and TNF-α levels. Calycopterin reduced intracellular ROS levels and increased catalase activity.
CONCLUSIONS:
The protective effect of this compound could represent a promising approach for the treatment of neurodegenerative diseases.

Phytotherapy Research, 2014, 28(11):1661-1670.

Antiangiogenic activity of xanthomicrol and calycopterin, two polymethoxylated hydroxyflavones in both in vitro and ex vivo models.[Reference: WebLink]

Our previous studies had shown xanthomicrol and Calycopterin, two plant-derived flavonoids, to have selective antiproliferative activity against some malignant cell lines. The present study is focused on the investigation of antiangiogenic potential of these two flavonoids, using in vitro and ex vivo models.
METHODS AND RESULTS:
Xanthomicrol and Calycopterin were found to have potent inhibitory effects on microvessel outgrowth in the rat aortic ring assay. Xanthomicrol was able to completely block microvessel sprouting at 10 µg/mL, and Calycopterin suppressed microvessel outgrowth by 89% at 5 µg/mL. Suramin and thalidomide, used at 20 µg/mL as positive controls, inhibited microvessel formation by 23% and 64%, respectively. The flavones also inhibited endothelial cell tube formation and human umbilical vein endothelial cell proliferation at 0.5, 5, and 10 µg/mL. In order to delineate the underlying mechanisms of antiangiogenic activity of these flavones, we investigated the influences of xanthomicrol and Calycopterin on expression of vascular endothelial growth factor (VEGF) and basic-fibroblast growth factor (b-FGF) in endothelial cells. These flavones were able to inhibit VEGF expression at 0.5, 5, and 10 µg/mL, but they had little or no effect on b-FGF expression.
CONCLUSIONS:
These findings suggest that xanthomicrol and Calycopterin possess potent antiangiogenic activities, which may be due to their inhibitory influences on VEGF expression.

Molecular & Cellular Biochemistry, 2014, 397(1-2):17-31.

Anticancer effect of calycopterin via PI3K/Akt and MAPK signaling pathways, ROS-mediated pathway and mitochondrial dysfunction in hepatoblastoma cancer (HepG2) cells.[Reference: WebLink]

Calycopterin is a flavonoid compound isolated from Dracocephalum kotschyi that has multiple medical uses, as an antispasmodic, analgesic, anti-hyperlipidemic, and immunomodulatory agents. However, its biological activity and the mechanism of action are poorly investigated.
METHODS AND RESULTS:
Herein, we investigated the apoptotic effect of Calycopterin against the human hepatoblastoma cancer cell (HepG2) line. We discovered that Calycopterin-treated HepG2 cells were killed off by apoptosis in a dose-dependent manner within 24 h, and was characterized by the appearance of nuclear shrinkage, cleavage of poly (ADP-ribose) polymerase and DNA fragmentation. Calycopterin treatment also affected HepG2 cell viability: (a) by inhibiting cell cycle progression at the G2/M transition leading to growth arrest and apoptosis; (b) by decreasing the expression of mitotic kinase cdc2, mitotic phosphatase cdc25c, mitotic cyclin B1, and apoptotic factors pro-caspases-3 and -9; and (c) increasing the levels of mitochondrial apoptotic-related proteins, intracellular levels of reactive oxygen species, and nitric oxide. We further examined the phosphorylation of extracellular signal-related kinase (ERK 1/2), c-Jun N-terminal kinase, and p-38 mitogen-activated protein kinases (MAPKs) and found they all were significantly increased in HepG2 cells treated with Calycopterin. Interestingly, we discovered that treated cells had significantly lower Akt phosphorylation.
CONCLUSIONS:
This mode of action for Calycopterin in our study provides strong support that inhibition of PI3K/Akt and activation of MAPKs are pivotal in G2/M cell cycle arrest and apoptosis of human hepatocarcinoma cells mediated by Calycopterin.