No abstract

The present study examined the effects of black tea (Camellia sinensis) extracts (BTE) in Caenorhabditis elegans under various abiotic stressors. Results showed BTE increased nematode resistance to osmosis, heat, and UV irradiation treatments. However, BTE could not increase nematodes' lifespan under normal culture conditions and MnCl2-induced toxicity at concentrations we used. Further studies showed that BTE decreased reactive oxygen species and up-regulated some antioxidant enzymes, including GSH-PX, and genes, such as gsh-px and sod-3. However, only a slight extension in mev-1 mutants mean lifespan was observed without significance. These results indicated that the antioxidant activity of BTE might be necessary but not sufficient to protect against aging to C. elegans. Moreover, BTE increased the mRNA level of stress-response genes such as sir-2.1 and sek-1. Our finding demonstrated BTE might increase heat and UV stress resistance in a sir.2.1-dependent manner. Taken together, BTE enhanced stress resistance with multiple mechanisms in C. elegans.

Fuzhuan brick tea (FBT) is traditionally consumed by the ethnic group in the border region of northwest China. The unique yellow fungal (Eurotium cristatum) growth phase is considered to be the key process point in the manufacture of the brick tea. The fungi from FBT are not only strongly correlated to the quality of brick tea, but also have the potential function of preventing obesity. The water extract of fungi (100 μg/mL) can significantly inhibit fat deposition in 3T3-L1 adipocyte and Caenorhabditis elegans. Furthermore, the inhibition of 3T3-L1 adipocyte formation was not due to the suppression on cell viability.

The study was conducted to evaluate the effects of fish oil replacement by vegetable oils on growth performance, histology, and antioxidant capacity of Macrobrachium rosenbergii. Three isonitrogenous and isoenergetic diets were formulated with different lipid sources included. DFO diet contained 6% fish oil, whereas DSO and DRO diets included 6% soybean oil and rapeseed oil (RO) as alternatives for fish oil, respectively. Prawns were fed thrice daily for 8 weeks. The results showed that prawns in DFO group showed significantly lower final weight, weight gain ratio, and specific growth rate (SGR), but higher feed intake and feed coefficient ratio than those in DSO and DRO groups. In hepatocellular ultrastructure, malformed and atrophic nucleus and higher apoptosis ratio were observed in DFO group. In addition, levels of haemolymph proinflammatory cytokines, activities of anti-superoxide anion, inducible-type NO-synthase (iNOS) and content of nitric oxide, and hepatopancreas NF-κB signal pathway gene expression in DFO group increased markedly compared to those of DSO and DRO groups. The results suggested that vegetable oils, such as soybean oil and RO might be the better lipid sources in diets for Macrobrachium rosenbergii than fish oil, it may be attributed to modified oxidative status induced by NF-κB-NO signal pathway.

Rhynchosia volubilis Lour has been a major drug in a folk prescription for contraception in China, whereas its mechanism remains unknown. Its antifertility effects on male mice and antimicrobial activities on sexually transmitted infection (STI) pathogens were previously reported. This study was undertaken to develop the n-Butanol extract of Rhynchosia volubilis Lour (BERVL) as a spermicidal agent with STI prevention. The spermicidal activities of BERVL with different doses were assessed using selected high-motile sperms of normal human semen samples, and their inhibitory effects on Lactobacillus acidophilus were determined. The mechanism of the spermicidal activity was explored by aqueous Eosin Y and Hoechst 33342/PI staining. The results showed spermicidal activities and inhibitory effects of BERVL on Lactobacillus acidophilus were dose-dependent. Dose of 90 mg/mL BERVL terminated all progressive sperm motility within 2 min, and had slight inhibitory effect on Lactobacillus acidophilus, suggesting it was an effective and safe dose for contraception use. About 80% sperms exposed to BERVL displayed changes consistent with high permeability of head membrane. It is concluded that BERVL as spermicide has advantages over N-9 with strong ability to instantaneously kill human sperm and possesses light inhibitory effect on Lactobacillus acidophilus.