Xi Xin

Herba Asari, Wild Ginger

Dosage

1-3g of the decoction is orally taken.

Toxicity

LD50 (mice/i.p.): 1.02 ± 0.04mg/kg (Liao Xi Xin); (1) 247mg/kg (Hua Xi Xin).

Chemical Composition

a-pinene; Camphene; Myrcene; b-pinene; b-terpinene; Limonene; Sabinene; b-bisabolene; 1,8-cineole; Terpinolene; P-cymene; g-terpinene; Berneol; Estragole; Eucarvone; Asaricin; Safrole; Myristicin; Croweacin; Methyleugenol; Elemicin; b-phellandrene; Isoborneol; Epicamphor; Bomylacetate; a-terpineol; Pentadecane; Kakuol; Asarone; Terpinen-4-ol; Naphthalene; N-pentadecane; 3,5-dimethoxytoluene; Kaempferol--3-glucoside (I); Kaempferol-3-gentiobioside (III); Kaempferol-3-rutinoside (II); 3,4-dimethyl-2,4,6-octatriene; 2-isopropyl-5-methylan isole; 2-isopropyl-5-methylphenyl ether. (2) , (3) , (4) , (5) , (6) , (7)

Precautions

Patients suffering from deficiency of yin, blood and qi, hyperhidrosis and excessive internal heat should avoid using the herb. The herb is incompatible with Li Lu (Radix Veratro Nigri). Over-dose of Xi Xin can cause flush, dizziness, hyperhidrosis, chest distress, palpitation, nausea, vomiting and other side effects. Xi Xin has some detrimental effects on the kidney; therefore, patients suffering from renal dysfunction should use with caution. (8) One case of arrhythmia and one case of heart failure are reported to have resulted from overdose of Xi Xin. (9) , (10) Two workers have reportedly collapsed while processing Xi Xin. (11)

Pharmacology

Effects on smooth muscles

Asarum oil can relax the isolated aorta of rabbits, causing the dosage-effect curve of noradrenalin-induced contraction of aorta to shift right, and reduce the effect of noradrenalin. It also decreases the perfusion flow in the isolated rabbit ear, and improves mice tolerance for oxygen deficiency under normal pressure. (12)

Effects on the central nervous system (analgesic, sedative and antipyretic effects)

Administered i.p. at 1.2ml/kg, 1.5% Hua Xi Xin oil has a significant antipyretic effect on typhoid vaccine-induced fever in rabbits. Administered to guinea pigs at 2ml/kg i.p., it has a limited temperature-reducing effect. (13) Experiments on animals show that the volatile oils of Liao Xi Xin, single-leafed asarum, small-leafed Ma Ti Xiang can produce similar antipyretic, temperature-reducing, analgesic and anticonvulsive effects, with those produced by Liao Xi Xin being the more pronounced. It is speculated that methyleugenol may be the active component that triggers the inhibitory effects on the central nervous system. (14)

Anti-inflammatory effects

Administered to rats at 0.12ml/kg to 0.96ml/kg i.p., Liao Xi Xin oil has a significant inhibitory effect on carragenin-induced swelling in the feet. Liao Xi Xin oil can also significantly reduce the content of histamine in the infected tissue and in the exudate, but has no significant effect on the contents of 5-HT and PGE2. (15) Administered by abdominal injection, the volatile oils of Mao Xi Xin or Liao Xi Xin can inhibit granuloma formation in rats. The effect is related to the reduction of zinc content in blood serum. (16)

Immune-inhibiting effects

Hemolytic plaque tests, macrophage phagocytic function tests, and leukocyte migration inhibition tests all show that Xi Xin can significantly inhibit immune functions in mice. Further tests have shown that this effect is related to its influence on the distribution of the T cell subgroup and the production of b-endorphin in experimental mice. (17)

Effects on the cardiovascular system

In-vitro experiments show that different concentrations of Xi Xin decoction (1500ìg/ml or 200ìg/ml) can decrease the LDH released into the culture medium by damaged cardiac muscle cells. Compared to both the sugar- and oxygen-free group and to the group of normal levels of sugar and oxygen, the differences are significant (P

Counteracting lipid peroxidation

Experiments on animals show that asarum can effectively reduce lipid peroxidation, thus decreasing the content of LPO in the tissue and avoiding the destruction of cellular structure and function by harmful substances. Asarum also tends to enhance SOD activity, strengthen the body's ability to eliminate free radicals, and lessen free radicals damage to the body. (18)

References

  1. Qu Shu Yan, et al. Journal of Pharmacology. 1983;17(1):12-16.
  2. Xu Zhi Lin, et al. Traditional Chinese Medicine Bulletin. 1984;9(1):27.
  3. Tian Zhen, et al. Pharmacy Bulletin. 1981;16(2):53.
  4. Tian Zhen, et al. Journal of Beijing Medical College. 1981;13(3):179-181.
  5. Wang Dong, et al. Journal of Chinese Materia Medica. 1998;29(2):83-84.
  6. Tian Zhen, et al. Journal of Beijing Medical College. 1981;13(4): 282-284.
  7. Editorial Committee of Chinese Materia Medica. State Drug Administration of China. Chinese Materia Medica. Shanghai: Science and Techonology Press; 1998.
  8. Pharmacopeia of the People. Republic of China Medicine Dictionarys, vol. I. People's Health Press; 1977.
  9. Chen Xiao Qin, et al. Jiangsu Journal of TCM. 1994;15(1):10.
  10. Liu Fu Li, et al. China Journal of Chinese Medicine. 1995;20(7):440.
  11. Zhang Jia Fu. China Journal of Chinese Medicine. 1997;22(11):652.
  12. Xun Jun, et al. Journal of Chinese Patented Medicine. 1992;14(12):32-33.
  13. Qu Shu Yan, et al. Journal of Chinese Materia Medica. 1982;23(6):72-74.
  14. Sun Jian Ning, et al. China Journal of Pharmacy. 1991;26(8):470-472.
  15. Xie Wei, et al. Ninxia Journal of Medicine. 1995;17(2):121-124.
  16. Hong Cui Ying, et al. China Journal of Chinese Medicine. 1992;17(4):236-238.
  17. Chang Yu Zhen, et al. Shanghai Journal of Immunology. 1993;13:334-336.
  18. Jin Fan Po. Journal of Traditional Chinese Medicine Information. 1994;11(2):48.