Linderae Radix, the dry roots of Lindera aggregata (Sims) Kosterm, has long been used as traditional Chinese medicine for the treatment of various diseases, including chest and abdomen pain. The total alkaloids are believed to be the main active components responsible for the biological functions of Linderae Radix, and which have been shown to relieve the inflammation and to protect joints from destruction in mouse collagen-induced arthritis.

Here, the total alkaloids of ten batches Linderae Radix collected from both mainland China and Hong Kong were determined. In total, we isolated 12 individual alkaloids, including norisoboldine, lindcarpine, boldine, linderaline, isoboldine, reticuline, N-methyllaurotetanine, actinodaphine, norjuziphine, pallidine, secoboldine, secolaurolit...[ Read more ]

Linderae Radix, the dry roots of Lindera aggregata (Sims) Kosterm, has long been used as traditional Chinese medicine for the treatment of various diseases, including chest and abdomen pain. The total alkaloids are believed to be the main active components responsible for the biological functions of Linderae Radix, and which have been shown to relieve the inflammation and to protect joints from destruction in mouse collagen-induced arthritis.

Here, the total alkaloids of ten batches Linderae Radix collected from both mainland China and Hong Kong were determined. In total, we isolated 12 individual alkaloids, including norisoboldine, lindcarpine, boldine, linderaline, isoboldine, reticuline, N-methyllaurotetanine, actinodaphine, norjuziphine, pallidine, secoboldine, secolaurolitsine, and sesquiterpene linderane. HPLC analysis revealed that the 7 isoquinoline alkaloids, e.q. norisoboldine, boldine, linderaline, isoboldine, reticuline, N-methyllaurotetanine, norjuziphine, were the major alkaloids in Linderae Radix. Norisoboldine was the most abundant alkaloid in this herbal extract, and meanwhile linderane was considered to be the indicative constituent for herbal identification. Here, norisoboldine and linderane were chosen as the chemical markers in quality control of Linderae Radix. Macroscopic and microscopic identifications were prepared according to the requirements listed in the latest edition of Chinese Materia Medica Standards of Hong Kong. Thin layer chromatography and high performance liquid chromatograph fingerprinting were found to have good separation and high repeatability for identification of Linderae Radix. Thus, HPLC fingerprint could be used as sensitive and steady method to evaluate the quality of Linderae Radix from different cultivated regions. By HPLC analysis, the quantitative determination of active chemical markers was revealed under an optimized extraction method.

In the study of anti-inflammatory, 7 isoquinoline alkaloids, norisoboldine, boldine, linderaline, isoboldine, reticuline, N-methyllaurotetanine, norjuziphine, were investigated by its effects on the gene transcription of two major pro-inflammatory cytokines, interleukin-6 (IL-6) and interleukin-1β (IL-1β), in cultured macrophage RAW 264.7 cells. Our results showed that boldine and isoboldine inhibited the mRNA expression of these two cytokines stimulated by lipopolysaccharide. In contrast, linderaline inhibited the increased level of lipopolysaccharide – induced IL-1β expression.

The current studies have developed a series of qualitative and quantitative methodologies facilitating for the quality analysis of Linderae Radix. Furthermore, the identification of active compounds from Linderae Radix showing effect in anti-inflammation could provide a plausible explanation for the therapeutic functions of this herb. Thus, the development of Linderae Radix of a safe and effective drug in treating inflammation, especially in rheumatoid arthritis, could be encouraged.