Aesculin offers increased resistance against oxidative stress and protective effects against Aß-induced neurotoxicity in Caenorhabditis elegans.

Aesculin, a coumarin compound, is one of the major active ingredients of traditional Chinese herbal medicine Qinpi (Cortex Fraxini), which has been reported to exhibit antioxidative, anti-inflammatory and neuroprotective properties against oxidative stress and cellular apoptosis. However, the regulatory mechanisms remain poorly characterized in vivo. This research was performed to explore the underlying molecular mechanisms behind aesculin response conferring oxidative stress resistance, and the protective effects on amyloid-ß (Aß)-mediated neurotoxicity in Caenorhabditis elegans. Study indicated that aesculin plays the protective roles for C. elegans against oxidative stress and Aß-mediated neurotoxicity and reduces the elevated ROS and MDA contents through enhancement of antioxidant defenses. The KEGG pathway analysis suggested that the differentially expressed genes are mainly involved in longevity regulating pathway, and the nuclear translocation of DAF-16 and the RNAi of daf-16 and hsf-1 indicated that DAF-16 and HSF-1 play critical roles in integrating upstream signals and inducing the expressions of stress resistance-related genes. Furthermore, the up-regulated expressions of their target genes such as sod-3 and hsp-16.2 were confirmed in transgenic GFP reporter strains CF1553 and CL2070, respectively. These results indicated that the regulators DAF-16 and HSF-1 elevate the stress resistance of C. elegans by modulating stress-responsive genes. Further experiments revealed that aesculin is capable of suppressing Aß-induced oxidative stress and apoptosis and improves chemosensory behavior dysfunction in Aß-transgenic nematodes. In summary, this study suggested that aesculin offers increased resistance against oxidative stress and protective effects against Aß-induced neurotoxicity through activation of stress regulators DAF-16 and HSF-1 in nematodes.

SP94 Peptide-Functionalized PEG-PLGA Nanoparticle Loading with Cryptotanshinone for Targeting Therapy of Hepatocellular Carcinoma.

To achieve improved drug delivery efficiency to hepatocellular carcinoma (HCC), biodegradable poly (ethylene glycol)-poly (lactic-co-glycolic acid) (PEG-PLGA) nanoparticles (NP), surface-modified with SP94 peptide, were designed for the efficient delivery of cryptotanshinone to the tumor for the treatment of HCC. Cryptotanshinone NP and SP94-NP were prepared by using nanoprecipitation. The physicochemical and pharmaceutical properties of the NP and SP94-NP were characterized, and the release kinetics suggested that both NP and SP94-NP provided continuous, slow release of cryptotanshinone for 48 h. The in vitro cellular experiment demonstrated that SP94-NP significantly enhanced the cellular uptake of cryptotanshinone and induced high cytotoxicity and cellular apoptosis of hepatocellular carcinoma (HepG2) cells. The in vivo detecting results of targeting effect using the Cy5.5 probe evidenced that SP94-NP showed an accumulation in tumor more efficiently than that of unconjugated ones. Meanwhile, SP94-NP exhibited the smallest tumor size than other groups and showed no toxicity to body. The results of this study provide a promising nanoplatform for the targeting of HCC.

Mulberry leaf flavonoids protect against glucotoxicity-induced INS-1 cell apoptosis.

OBJECTIVE: To investigate the effect of mulberry leaf flavonoids (MLF) on apoptosis of pancreatic cells induced by high glucose. METHODS: Long exposure to high glucose induces apoptosis of pancreatic ß cells, which can lead to diabetes. In this study, we used the rat insulinoma cell line, INS-1. High glucose (33.3 mM) was used to establish a glucotoxicity model. The MTT assay was used to evaluate the MLF effect on cell viability. INS-1 cells were treated with various concentrations of MLF (125, 250 and 500 mg/L) for 24 h, and then stimulated with 5.5 or 33.3 mM glucose for 48 h. Then, the cell supernatants were collected for enzyme-linked immunosorbent assay to determine the level of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor a (TNF-α) and interleukin 6 (IL-6). Western blotting was used to determine the expression of Bcl-2, Bax, caspase-3 and Caspase-9. Cell apoptosis was measured by Annexin V-FITC/propidium iodide double staining and flow cytometry. RESULTS: MLF (125-500 mg/L) improved cell viability. Furthermore, MLF (250 and 500 mg/L) inhibited apoptosis induced by high glucose. The anti-apoptosis effect of MLF was associated with increased SOD, CAT and GSH-Px expression, as well as reduced MDA levels in high-glucose-treated INS-1 cells. Moreover, MLF upregulated Bcl-2 expression, downregulated Bax expression, and reduced the expression of caspase-3 and Caspase-9. Finally, MLF decreased the secretion of inflammatory cytokines and insulin in high-glucose-induced INS-1 cells. CONCLUSION: MLF is a potential therapeutic agent for preventing diabetes and related disorders.