Effect of lead pollution on anticoagulant effect of Whitmania pigra based on in vitro anticoagulation experiment
Quality study published in China Journal of Chinese Materia Medica (2019)
Abstract
Leech has a good anticoagulant activity and is one of the raw materials for treatment of many cardiovascular and cerebrovascular diseases. This study was based on in vitro anticoagulant experiments( APTT and PT) to investigate the effects of lead contamination on the anticoagulant effect of leech. At present,the Hirudo circulating in the market are dominated by Whitmania pigra,therefore Wh. pigra were cultivated under a different lead pollution for 50 days. Then,the effects of Wh. pigra extract,extracting from different cultivating environment,on activated partial thrombin time( APTT) and prothrombin time( PT) were determined by automatic coagulation instrument. The results showed that the Wh. pigra extract significantly prolonged the APTT compared with the saline group.The APTT of the lead-high residual Wh. pigra was shorter than that of the blank Wh. pigra. The Wh. pigra extracts from different treatment groups had little effect on PT. The results showed that the lead residue in the Wh. pigra increased with the increase of lead in the cultured soil,the lead residual of the Pb-H group was( 10. 66±2. 79) mg·kg~(-1),which exceeded the lead limit specified in the 2015 edition of the Chinese Pharmacopoeia. The results indicated that growth environment pollution is one of the important factors causing excessive lead in Wh. pigra. Lead pollution will reduce the anticoagulant effect of Wh. pigra and affect its clinical efficacy.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Demonstrates lead pollution reduces anticoagulant potency of Whitmania pigra extracts in vitro — has implications for medicinal leech supply chains.
Why This Matters for Hirudotherapy
This study used in vitro anticoagulation experiments (APTT and PT) to investigate the effects of lead contamination on the anticoagulant efficacy of Whitmania pigra, measuring clotting times of extracts from leeches cultivated under different lead pollution conditions for 50 days using an automatic coagulation instrument. Results showed that W. pigra extract significantly prolonged APTT versus saline, but lead-high residual leeches had shorter APTT than uncontaminated leeches; PT was little affected across groups. Lead residues in the high-exposure group (10.66 ± 2.79 mg·kg⁻¹) exceeded limits in the 2015 Chinese Pharmacopoeia, indicating growth environment pollution reduces anticoagulant efficacy. This is relevant to ASH's domain as it demonstrates that environmental lead directly diminishes the therapeutic potency of a widely used medicinal leech species. However, only in vitro coagulation assays were used; no in vivo or clinical assessment of therapeutic impact was performed.
Citation
Effect of lead pollution on anticoagulant effect of Whitmania pigra based on in vitro anticoagulation experiment.
Luo XM et al. · Zhongguo Zhong yao za zhi, 2019
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