Y̱u P̠ing F̠eng S̠an (YPFS; Jade screen powder; 玉屏風散), a Chinese herbal decoction comprised of A̱stragali Ṟadix (AR; Huangqi), A̱tractylodis M̱acrocephalae Ṟhizoma (AMR; Baizhu) and S̱aposhnikoviae Ṟadix (SR; Fangfeng). Clinically, YPFS has been widely used to regulate immune functions; however, the action mechanism of which is not known. Here, we addressed this issue by providing detail analyses of chemical and biological properties of YPFS.

In order to standardize YPFS chemically, a typical HPLC fingerprint of YPFS at absorbance of 210 nm was developed: the fingerprint was used to ensure the detection of the chosen chemical markers from the herbal extracts. More important this fingerprint served as an index for identification of YPFS. Moreover, we developed a rapid resol...[ Read more ]

Y̱u P̠ing F̠eng S̠an (YPFS; Jade screen powder; 玉屏風散), a Chinese herbal decoction comprised of A̱stragali Ṟadix (AR; Huangqi), A̱tractylodis M̱acrocephalae Ṟhizoma (AMR; Baizhu) and S̱aposhnikoviae Ṟadix (SR; Fangfeng). Clinically, YPFS has been widely used to regulate immune functions; however, the action mechanism of which is not known. Here, we addressed this issue by providing detail analyses of chemical and biological properties of YPFS.

In order to standardize YPFS chemically, a typical HPLC fingerprint of YPFS at absorbance of 210 nm was developed: the fingerprint was used to ensure the detection of the chosen chemical markers from the herbal extracts. More important this fingerprint served as an index for identification of YPFS. Moreover, we developed a rapid resolution liquid chromatography coupled with mass spectrometry method to simultaneously identify different chemicals from the three herbs, as a means of quality assessment for YPFS. These marker chemicals included: (i) AR-derived flavonoids: calycosin-7-O-β-D-glucoside, calycosin, ononin and formononetin; (ii) AR-derived saponins: astragaloside IV, III and II; (iii) AMR-derived sesquiterpenoids: atractylenolide I, II and III; (iv) SR-derived chromones prim-O-glucosylcimifugin and 5-O-methylvisammioside; and (v) SR-derived coumarins: scopoletin, isopsoralen and psoralen. In this case, the quantity of these chemicals might be used not only for quality control of YPFS, but also for elucidation of the compatible principle. In addition, the chemical analysis could serve a parameter for chemical standardization and repeatability of YPFS preparation. These values defined the minimal amount of chemicals for a standardized YPFS being prepared for each time, and which could be used as a quality index for the biological studies.

In order to reveal the immune functions of YPFS in innate immunity, the standardized extract was applied onto cultured murine macrophages. Innate immunity includes inflammatory response, phagocytosis and interferon (IFN) signaling. In cultured macrophages, the treatment of YPFS stimulated the expressions of pro-inflammatory cytokines and enzymes responsible for induction of inflammatory response, and this activation was mediated by nuclear factor kappa-light-chain-enhancer of activated B cells (NF-кB) signaling. In parallel, YPFS up regulated the phagocytic activity in cultured macrophages; induced the transcriptional activity of interferon stimulated response element; and triggered the anti-viral protein expressions. Conversely, YPFS was found to suppress neuraminidase activity of influenza viruses in epithelial cells, thereby preventing the viral release and spreading. Taken together, YPFS exerted anti-bacterial and anti-viral effects in innate immunity.

The loss control of sustained pro-inflammatory mediators might lead to chronic diseases. Here, we elucidated the anti-inflammatory effects of YPFS in lipopolysaccharide (LPS)-stimulated macrophages and endothelial cells. The application of YPFS in cultured small intestinal enterocytes markedly induced the expression of intestinal alkaline phosphatase in a time-dependent manner, which might strengthen the intestinal detoxification system. Thus, a duality of YPFS in modulating the expression of pro-inflammatory cytokines and enzymes was proposed here. Amongst the herbs in YPFS, AR and SR were the major herbs that activated the innate immunity as described here. In contrast, all the three herbs within YPFS showed strong anti-inflammatory effects. Moreover, AR-derived calycosin and formononetin were identified to be the active ingredients in stimulating innate immunity and anti-inflammatory effects.

The anti-multidrug resistance of YPFS was demonstrated. In cultured Caco-2 monolyer system, YPFS inhibited the efflux transport of AR-derived flavonoids, i.e. calycosin and formononetin. In parallel, the application with different inhibitors of efflux transporters, the transport of calycosin and formononetin was significantly reduced. In efflux transporter ATPase-enriched membrane system, YPFS inhibited the substrate-stimulated activities of efflux transporter ATPase indicating a role of YPFS in the transport. Cisplatin, an anti-cancer drug known to be efflux transported out of cancer cells resulting poor bioavailability, was selected as a target for testing the chemotherapy combination regimen with YPFS in cultured A549, a lung cancer cell line. YPFS increased the uptake of cisplatin in cultured A549 cells in a dose-dependent manner, and which suppressed the expression of efflux transporter. In cultures, application of calycosin and formononetin increased the cellular accumulation of cisplatin in a dose-dependent manner. Thus, calycosin and formononetin might exert anti-multidrug resistance as competitive inhibitors. The competitive chemotherapy combination regimen of cisplatin and calycosin/ formononetin, therefore, was proposed here.

Overall, the present study developed a chemical and biological assessment for YPFS; these findings included: (i) the minimal amounts of 15 chosen chemicals in YPFS have established as quality control parameters; (ii) the chemical solubilities of these chosen chemicals supported the compatible principle of YPFS; (iii) activations of inflammatory response, phagocytosis, anti-viral proteins and anti-inflammation were triggered in YPFS-treated cell models; (iv) anti-multidrug resistance of YPFS was found suggesting a possible role of YPFS in chemotherapy combination regime with anti-cancer drug.