Cytoprotective activity

Morel et al. (1993) have reported that three flavanoids (catechin, quercetin and diosmetin) are cytoprotective on iron-loaded hepatocyte cultures. Their cytoprotective activity (catechin > quercetin > diosmetin) correlated with their iron-chelating ability (Morel et al., 1993). These compounds should also be good phenolic antioxidants so iron chelation may only be part of the story. 

Beuerle F, Witte P, Hartnagel U, Lebovitz R, Parng C, Hirsch A (2007) Cytoprotective activities of water-soluble fullerenes in zebrafish models. J. Exp. Nanosci. 2 147-170. 

Aluminium-containing antacids exhibit cytoprotective activity or enhancement of natural mucosal defence mechanisms. 

Li, J. X., Q. Shi, Q. B. Xiong, J. K. Prasain, and Y. Texuka. 1998. Tribulusamide A and B, new hepatoprotective lignanamides from the fruits of Tribulus terrestris indications of cytoprotective activity in murine hepatocyte culture. Plant Med. 64 628-631. 

Das, B., Yeger, H., Baruchel, H., Freedman, M., Koren, G., and Baruchel, S. (2003). In vitro cytoprotective activity of squalene on a bone marrow versus neuroblastoma model of cisplatin-induced toxicity Implications in cancer chemotherapy. Eur. f. Cancer 39, 2556-2565. 

Rumbrin (181) from the fungus Auxarthron umbrinum exhibits cytoprotective activity against cell death caused by calcium overload in 3T3-Swiss albino cells. It also shows inhibitory activity against lipid peroxidation in rat brain homogenate and low intraperitoneal toxicity in mice [142]. 

Indirect Cytoprotective Activity of Plant Phenolic Compounds... 

DNA damage in the presence of cytochrome P450s (CYPs) and Cu(II) in vitro or in cells [Yoshino et al., 2004 Ahsan et al., 1999]. At higher concentrations curcumin exhibited genotoxicity and cytotoxicity in different systems [Cao et al., 2007]. At last, in vivo intervention trials using typical antioxidants such as ascorbate or carotenes yielded mostly disappointing results in terms of protection against oxidation-related diseases, sometime even increased the incidences of diseases [Stevenson and Hurst, 2007 Dinkova-Kostova and Talalay, 2008]. Obviously, the direct antioxidant capacity of plant phenolic compounds cannot explain their cytoprotective activities. 

INDIRECT CYTOPROTECTIVE ACTIVITY OF PLANT PHENOLIC COMPOUNDS AND CYTOPROTECTIVE ENZYMES... 

Investigation of replacement of the 5-methoxy group by substituents with different electronic and lipophilic properties and methylation of the indole nitrogen or its replacement by a sulfur atom was evidence for the shift of the 5-methoxy group to the 4-position of the indole nucleus led to the most active radical scavenger but much less effective as a cytoprotectant [135]. 5-alkoxy-2-(N-acylaminoethyl)indole (Fig. 15) appeared as the key feature to confer both antioxidant and cytoprotective activity to the structure. Antioxidant activity seems essential for cytoprotection, but it is not sufficient, and there is no statistically significant correlation between the two types of activity. 

The prostaglandin Ei and E2 analogues showing antisecretory and cytoprotective activities had to be deuterium or tritium labelled for preclinical studies. The tritiated or deuteriated title compounds 61, 62 and 63 have been synthesized by the methods outlined in equations 25, 26 and 27. Compounds 61 and 62, with hydrogen at 7-position... 

Acalypha wilkesiana van macafeana hort. Din et al. [236] studied the properties of Acalypha wilkesiana var. macafeana hort, used to heal wounds in Malaysian traditional medicine. Acalypha wilkesiana ar. macafeana hort. protected human hepatocellular liver carcinoma (HepG2) cells exposed to tert-butylhydroperoxide, and protected cells against oxidative injuries, showing potent antioxidant and cytoprotective activities. These effects might be exerted bygeraniin [236],... 

A synthetic bromine derivative ofgomisin J [(6/ ,7 SVV-biar)-4,9-dibromo -3,10-dihydroxy-1,2,11,12-tetramethoxy-6,7-dimethyl-5,6,7,8-tetrahydrodi-benzo[a,c]cyclooctene], was found to be a potent inhibitor of the cytopa-thic effects of HIV-1 on MT-4 human T cells (ED50, 0.1 to 0.5 pM). Comparison of various gomisin J derivatives with gomisin J itself showed that iodine, bromine, and chlorine in the fourth and ninth positions increased RT inhibitory activity as well as cytoprotective activity [161],... 

Donatus, I.A., Sardjoko, and N.P.E. Vermeulen. 1990. Cytotoxic and cytoprotective activities of curcumin—Effects on paracetamol-induced cytotoxicity, Upid-peroxidation and glutathione depletion in rat hepatocytes. Biochem. Pharmacol. 39(12) 1869-1875. 

H. Kessler, M. Gehrke, A. Haupt, M. Klein, A. Muller, K. Wagner, Common structural features of cytoprotection activities of somatostatin, antamanide and related peptides, Klin. Wo-chenschr. 64 74-78 (1986)... 

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