A Toxicological study of Traditional Chinese Medicine: Yin Qiao Chai Gui Granules

Long-term toxicity testing, also known as repeated dose toxicity tests, is a type of general toxicity tests and is an integral part and core component of non-clinical safety studies of drugs.

General toxicity testing usually involves exposing test subjects to a chemical substance for a relatively short period (usually a few weeks or less) to determine the potential health effects of the essence after long-term exposure.

In contrast, long-term toxicity testing involves exposing test subjects to a substance for a much more extended period, usually months or years, to determine the effects of long-term exposure. This type of testing is beneficial for assessing the chronic effects of a substance, such as the development of cancer or other chronic diseases.

Therefore, long-term toxicity testing is one of preclinical toxicology studies' most comprehensive, informative, and clinically relevant toxicological studies. Long-term toxicity testing is closely related to acute toxicity, reproductive toxicity, and carcinogenicity toxicology studies and is an essential link from pharmacological studies to clinical trials of drugs.

Yinqiao Chaigui Granules are used for the treatment of influenza. Toxicological studies were conducted on Yinqiao Chaigui Granules to observe the acute and long-term toxic effects of gavage administration of Yinqiao Chaigui Granules in rats and to provide a basis for safe clinical use. The experimental animal study was conducted to investigate the mechanism of action of Yin Qiao Chai Gui Granules in regulating immunity, protecting organs, and inhibiting viruses and to evaluate its safety and efficacy.

1,Toxicological study of Yin Qiao Chai Gui granules

It was reported that toxicological research was conducted on Yin Qiao Chai Gui Granules, and it was found that Yin Qiao Chai Gui Granules had no acute toxicity in rats; the non-toxic dose of 43.546 g (raw drug)/(kg-d) (equivalent to 60.48 times of the proposed clinical amount) was administered to rats by gavage for 30 days.

The acute toxicity test was conducted by gavage of 45.12 g (raw drug)-kg-1 [maximum permissible concentration of 2.256 g (natural medicine)-m L-1 at 20 m L-kg-1] in rats three times in 24 h. The rats were observed continuously for 14 d after administration, and the toxic reactions and deaths were recorded.

In the long-term toxicity test, rats were administered 7.560, 18.144, and 43.546 g (raw drug)/(kg-d) (equivalent to 10.5, 25.2, and 60.48 times the proposed clinical dose) of Yin Qiao Chai Gui pellets by gavage once-d-1 for 30 d. The general condition of rats was observed daily, and the body mass and food intake of rats were weighed weekly. For 30 d, 50% of the rats (half of each sex) were examined for hematology, blood biochemistry, electrolytes, and pathology; after the remaining rats stopped taking the drug for 14 d, the corresponding indexes were examined as before.

The results showed that the Yin Qiao Chai Gui granules dose was 135.36 g (raw drug)-kg-1 (equivalent to 188 times the proposed clinical amount) given to rats by gavage three times in 1 d. No acute toxic reactions were observed. No abnormal changes related to drug toxicity were observed in the rats after 30 d of drug administration and 14 d of drug withdrawal.

2, Animal experimental study on the treatment of influenza with Yin Qiao Chai Gui Granules

Methods: NIH mice were randomly divided into a standard control group, virus model group, amantadine group, and high, medium, and low dose groups of Chinese medicine. Under light anesthesia with ether, mice in each group were treated with 0.9% saline in the standard control group and nasal drops of FM1 dilution of influenza A virus in the remaining groups to establish the influenza virus infection model. The medicated groups were intervened with high, medium, and low doses of traditional Chinese medicine and amantadine. Then, the relevant indexes were tested according to the specific experimental arrangement of each part.

Mainly including experiments:

(1)Acute toxicity experiments;

(2)Pharmacodynamic studies related to Yin Qiao Chai Gui granules (including lung index and death protection effect studies);

(3)The effect of Yin Qiao Chai Gui granules on the phagocytosis function of macrophages in influenza virus FM1-infected mice.

Result

(1)Acute toxicity test: There was no death of mice in each dosing group. The Yin Qiao Chai Gui granules taken in the experiment were not significantly toxicogenic, and the drug was safe.

(2) Pneumonia inhibition in mice infected with influenza virus FM1: the lung index of the virus-infected group was significantly higher than that of the standard control group, and there was a significant difference (P0.05). Compared with the virus model group, the lung index of the amantadine group and the high, medium, and low-dose groups of Chinese medicine decreased. There was a significant difference (P0.05), and the dose of each group of Chinese medicine was negatively correlated with the lung index and positively correlated with the lung inhibition rate.

(3) Death protection effect on influenza virus FM1-infected mice: compared with the virus model group, the survival time was prolonged in the high and medium dose groups of traditional Chinese medicine with significant differences (P 0.05); 

the death protection rates of influenza virus-infected mice in the high, medium and low dose groups of traditional Chinese medicine were 35%, 25%, and 15%, respectively; the prolonged life rates were 38.06%, 32.26%, and 25.81%; (b) The protection rate against death in mice infected with influenza virus in the amantadine group was 60%; the prolongation of life rate was 43.31%.

(4) Effect on macrophage phagocytosis of influenza virus FM1-infected mice: the OD value of the virus model group was the lowest, compared with the standard control group, P0.01, the difference was significant, indicating that the macrophage phagocytosis of virus-infected mice was significantly reduced; the OD value of each drug treatment group was higher than that of the virus model group, the P value was 0.01, the difference was highly significant.

Conclusion: The above results indicate that Yin Qiao Chai Gui granules can effectively inhibit the inflammatory changes in the lungs of influenza virus-infected mice and prolong their survival time with apparent death-protective effects, and can improve the phagocytosis function of macrophages in mice after virus infection and play a role in regulating immune function.