Cinnabar Cinnabar Sedative Pills Safety Evaluation

Objective:To compare the toxicity of Cinnabar in Zhu-Sha-An-Shen Wan (ZSASW), and make a safety evaluation of Cinnabar in ZSASW.Method: The toxicity of Methylmercury (MeHg), Mercuric chloride(HgCl₂), Cinnabar and ZSASW was compared in cultured human liver HL-7702 cells, Phecochromocytoma (PC12)cells and rat astrocytes. Mice were given orally Cinnabar(20 g/kg) ,ZSASW(25 g/kg), MeHg(0.1 g/kg)and HgCl₂ (0.15g/kg) once, and the toxicity was examined for 7days. For chronic toxicity, Cinnabar(3 g/kg·d) ,ZSASW(20 g/kg·d), and HgCl₂ (0.03 g/kg·d) were given orally for 20 days and toxicity to the liver and kidney was examined by pathology. The accumulation of Hg and the expression of Metallothionein-2(MT-2)mRNA in liver and kidney was determined. In another study, Rats were orally given Cinnabar(0.2 g/kg·d) ,ZSASW(1.4 g/kg·d), and HgCl₂ (0.02 g/kg·d) and MeHg(0.001 g/kg·d) for 60 days to examine the toxicity. ResuLt:The LC50 towards human liver HL-7702 cells,PC12 cells or rat astrocyte cells of ZSAS or cinnabar was much higer than HgCl₂ or MeHg. Oral cinnabar at a does of 20 g/kg or ZSASW at a does of 25 g/kg did not kill mice, but no mice could survive MeHg at a does of 0.1 g/kg or HgCl₂ at a does of 0.15 g/kg. Subacute toxicity experiment indicated that HgCl₂ retarded body weight gain; with significant accumulation of Hg in the liver and kidney. In comparison, mercury accumulation after Cinnabar and ZSASW was insignificant. No apparent hepatic and renal dysfunctions were evident under experimental conditions, but the MT-2 mRNA levels were much higher in HgCl₂ group than other groups. Subchronic study (60 days) in SD rats showed that both ZSAS (1.4 g/kg, clinical dosage, po) and cinnabar (0.2 g/kg) were much less toxic than HgCl₂ (0.02 g/kg, po) or MeHg (0.001 g/kg, po), as evidenced by body weight loss, serology, and histopathology of brain, liver and kidney. Mercury accumulation in the brain,Liver and kidney in ZSAS- or cinnabar-treated groups was only slightly (10-70%) but not significantly higher than controls, while the mercury contents in HgCl₂- and MeHg-treated groups were 3-15 folds higher. The expression of kidney injury molecule-1 was increased 60-fold by MeHg, 3-fold by HgCl₂, but was unchanged by ZSAS or cinnabar, consistent with the histopathology observations. In addition, the expression of kidney MT-1, MT-2 and MT-3 mRNA levels were lower in MeHg and HgCl₂ groups than ZSAS or cinnabar. In liver, GSP-pi mRNA levels were much higher in MeHg and HgCl₂ groups than ZSAS or cinnabar. In brain, the expression of MT-3 and brain derived neurotrophic factor (BDNF) mRNA levels were much higher in ZSAS than other groups .Conclusion: The vitro cells toxicity, acute toxicity, subacute toxicity or subchronic toxicity of Cinnabar in ZSASW is much less than HgCl₂ or MeHg. The results indicate that the toxicity of mercury in different forms vary greatly. It is inapppropriate to evaluate the security of Cinnabar in ZSASW based on total mercury content.