Variability pattern and correlation studies in Silybum marianum Gaertn

Molecular insights of genetic variation in milk thistle (Silybum marianum [L.] Gaertn.) populations collected from southwest Iran

Milk thistle (Silybum marianum) is among the world's popular medicinal plants. Start Codon Targeted (SCoT) marker system was utilized to investigate the genetic variability of 80 S. marianum genotypes from eight populations in Iran. SCoT marker produced 255 amplicons and 84.03% polymorphism was generated. The SCoT marker system's polymorphism information content value was 0.43. The primers' resolving power values were between 4.18 and 7.84. The percentage of polymorphic bands was between 33.3 and 100%. The Nei's gene diversity (h) was 0.19-1.30 with an average 0.72. The Shannon's index (I) ranged from 0.29 to 1.38 with an average value of 0.83. The average gene flow (0.37) demonstrated a high genetic variation among the studied populations. The variation of 42% was displayed by the molecular variance analysis among the populations while a recorded variation of 58% was made within the populations. Current investigation suggested that SCoT marker system could effectively evaluate milk thistle genotypes genetic diversity.

Milk thistle extracts inhibit the oxidation of low-density lipoprotein (LDL) and subsequent scavenger receptor-dependent monocyte adhesion

Silymarin encompasses a group of flavonolignans that are extracted from Silybum marianum (Asteraceae) fruits. The silymarins have previously been reported to lower low-density lipoprotein (LDL) levels associated with high-fat diets. The present study reports the efficacy of the silymarins in inhibiting oxidized low-density lipoprotein (oxLDL) generation and subsequent scavenger receptor (SR) mediated monocyte adherence to oxLDL. The flavonolignans that comprise silymarin include silichristin (SC), silidianin (SD), silibinin (SBN), and isosilibinin (IS). These flavonolignans (300 microM) lowered oxLDL generation, measured by the thiobarbituric acid-reacting substances (TBARS) assay, by 60.0, 28.1, 60.0, and 30.1%, respectively. SBN treatment of LDL in the presence of copper sulfate (CuSO 4) resulted in a significant dose-dependent inhibition of monocyte adhesion. Inhibition was paralleled by a decrease in binding of anti-oxLDL antibodies recognized by U937 monocyte Fc gamma receptors (FcgammaR). These results showed that silymarin and SBN, likely through antioxidant and free radical scavenging mechanisms of action, inhibit the generation of oxLDL and oxidation-specific neoepitopes recognized by SR and FcgammaR expressed on monocytes/macrophages.

Genetic properties of milk thistle ecotypes from Iran for morphological and flavonolignans characters

The aim of present study was to investigate the genetic variation within and between 32 milk thistle ecotypes collected from northern (23 accessions) and southern (9 accessions) regions of Iran along with two introduced varieties, CN seeds and Budakalaszi, for morphological and flavonolignans properties. The two collections were assessed at separate field experiments. MANOVA for all the morphological traits showed significant difference between ecotypes. Univariate ANOVA verified these differences for most of the traits in the northern ecotypes (first collection) while for southern ecotypes no significant differences were obtained for the studied traits except seed yield. Among and within ecotypes genotypic coefficient of variation indicated higher level of variation among ecotypes than within ecotypes. In both of the experiments, there was a large genetic variation for silybin and silymarin quality and quantity. Cluster analysis of 34 accessions was performed for morphological traits and silymarin and silybin characteristics, separately. The resulting dendrogram based on silybin and silymarin characteristics revealed that the native accessions such as Dezfoul, Fereydounkenar and Nour, had highest flavonolignans and they were better than the foreign varieties. Also, there was no clear relationship between clustering based on morphological traits and flavonolignan compounds.