EVALUATION OF THE ACUTE AND SUBCHRONIC TOXICITY OF L. F.

Background: L. f. is used as a traditional Chinese drug to relieve cough and asthma symptoms and to eliminate phlegm. However, L. f. possesses toxicity, and little systematic research has been conducted on its toxic effects in the laboratory.

Methods And Materials: The acute group was administered 75% alcohol extract of L. f. in a single dose. A subchronic toxicity study was performed via daily oral administration of L. f. at a dose of 0.34 g/kg body weight in SD rats. The rats were divided into six groups: a petroleum ether extract (PEA) group, an ethyl acetate extract (EEA) group, an n-butyl alcohol extract (NEA) group, a remaining lower aqueous phases (REA) group, a 75% alcohol extract (AEA) group and a control group. Quantitative measurements of cytokines were obtained by fluorescence with a laser scanner using a Cy3 equivalent dye.

Results: The LD of the 75% alcohol extract of L. f. was 15.74 g/kg bw. In the subchronic toxicity study, no significant differences were observed among groups in relative organ weights, urine traits, liver antioxidase levels, or cytokine levels. However, significant sporadic differences were observed in body weight gains, haematology indices, biochemistry values, and histopathology features in PEA, EEA group. In addition, sporadic changes in other groups in measures such as WBC, MCHC, CK, ALP, AST, ALT, LDH, T-BIL, LDL-C, HDL-C, and TC were observed.

Conclusion: The toxicity study showed that L. f. can produce toxic effects, mainly on the liver; much less on the heart. The LD was 15.74 g/kg BW in mice, and the subchronic toxicity study, used a dosage of 0.34 g/kg/d.BW, showed that the toxic components of L. f. were mainly concentrated in the petroleum ether fraction, followed by the ethyl acetate fraction, the n-butyl alcohol fraction, the lower aqueous phase and the 75% ethanol extracts. PEA, petroleum ether extract of L. f.; EEA, ethyl acetate extract of L. f.; NEA: n-butyl alcohol extract of L. f.; REA: lower aqueous phases of L. f.; AEA, 75% alcohol extract of L. f.; WBC, white blood cell; RBC, red blood cell, PLT, platelet; HCT, haematocrit; MCV, mean corpuscular volume; HGB, haemoglobin; MCH, mean corpuscular haemoglobin; MCHC, mean corpuscular haemoglobin concentration; CREA, creatinine; LDH, lactate dehydrogenase; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; T-BIL, total bilirubin; ALT, alanine aminotransferase; ALP, alkaline phosphatase; AST, aspartate aminotransferase; TP, total protein; ALB, albumin; Glu, glucose; TC, total cholesterol; TG, triglycerides; CK, creatine kinase; GSH, Glutathione; MDA, malondialdehyde; T-SOD, total superoxide dismutase; TNF, tumour necrosis factor; IFN, interferon; MCP, monocyte chemotactic protein C.