RESUMEN
Trypsin inhibitors derived from plants have various pharmacological activities and promising clinical applications. In our previous study, a Bowman-Birk-type major trypsin inhibitor from foxtail millet bran (FMB-BBTI) was extracted with antiatherosclerotic activity. Currently, we found that FMB-BBTI possesses a prominent anticolorectal cancer (anti-CRC) activity. Further, a recombinant FMB-BBTI (rFMB-BBTI) was successfully expressed in a soluble manner in host strain Escherichia coli. BL21 (DE3) was induced by isopropyl-ß-d-thiogalactoside (0.1 mM) at 37 °C for 3.5 h by the pET28a vector system. Fortunately, a purity greater than 93% of rFMB-BBTI with anti-CRC activity was purified by nickel-nitrilotriacetic acid affinity chromatography. Subsequently, we found that rFMB-BBTI displays a strikingly anti-CRC effect, characterized by the inhibition of cell proliferation and clone formation ability, cell cycle arrest at the G2/M phase, and induction of cell apoptosis. It is interesting that the rFMB-BBTI treatment had no obvious effect on normal colorectal cells in the same concentration range. Importantly, the anti-CRC activity of rFMB-BBTI was further confirmed in the xenografted nude mice model. Taken together, our study highlights the anti-CRC activity of rFMB-BBTI in vitro and in vivo, uncovering the clinical potential of rFMB-BBTI as a targeted agent for CRC in the future.
Asunto(s)
Neoplasias Colorrectales , Extractos Vegetales , Proteínas de Plantas , Setaria (Planta) , Inhibidores de Tripsina , Animales , Humanos , Masculino , Ratones , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Expresión Génica , Ratones Endogámicos BALB C , Ratones Desnudos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Proteínas de Plantas/genética , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/farmacología , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Setaria (Planta)/genética , Setaria (Planta)/química , Inhibidores de Tripsina/farmacología , Inhibidores de Tripsina/aislamiento & purificación , Inhibidores de Tripsina/químicaRESUMEN
The physicochemical properties, structural features and structure-immunomodulatory activity relationship of pectic polysaccharides from the white asparagus (Asparagus officinalis L.) skin were systematically studied. Using sequential ethanol precipitation, five sub-fractions namely WASP-40, WASP-50, WASP-60, WASP-70 and WASP-80 with distinct degree of esterification (DE) and molecular weight (Mw) were obtained. The Mw and DE values were decreased with the increase of the ethanol concentrations. Structurally, although 4-α-D-GalpA was the dominant sugar residue in all fractions, the molar ratios were decreased, whereas other sugar residues including arabinose- and mannose-based sugar residues overall increased with the increase of ethanol concentration. In addition, the effects of sub-fractions on the RAW 264.7 cells indicated that pectic polysaccharides with the higher DE value showed a stronger immunomodulatory activity. Moreover, the structure-activity relationship was also discussed in this study, which extends the value-added application of asparagus and its processing by-products.