Calycosin induces apoptosis in adenocarcinoma HT29 cells by inducing cytotoxic autophagy mediated by SIRT1/AMPK-induced inhibition of Akt/mTOR.

Autophagy promotes cell survival or induces apoptosis in cancer cells. While SIRT1 and AMPK induce autophagy in both normal and cancer cells, Akt and mTOR can inhibit it. Calycosin, a methoxyisoflavone, protects against several types of solid tumours including colorectal cancer. However, the mechanisms behind the antitumour effect of Calycosin remain largely unknown. This study investigates if autophagy mediates the anti-tumourigenesis effect afforded by Calycosin and examines if this effect involves activation of SIRT1 and/or AMPK. Human colorectal (HT29) carcinoma cells were cultured under normal conditions with Calycosin (50 µmol/L) in the presence or absence of chloroquine (10 µmol/L), EX-527 (100 nmol/L, SIRT1 inhibitor), or IGF-1 (100 ng/mL, Akt/mTOR activator) for 48 hours. Calycosin inhibited cell growth, proliferation and invasion and increased protein levels of Beclin-1 and LC3II, markers of autophagy. It significantly increased protein levels of cleaved caspase-3, Bax, and SIRT1, and activity of AMPK and reduced those of Bcl-2. These effects were parallel with concomitant reduction in protein levels p-src, integrin-ß1 and Cyclin-D1 and activities of Akt and mTOR. Inhibition of autophagy by CQ reversed all these effects except cell invasion. Interestingly, co-incubating the cells with either EX-527 or IGF-1 completely prevented Calycosin-induced autophagy and all other associated effects and increased cell invasion. Also, blockade of SIRT-1 prevented the activation of AMPK, Akt, and mTOR, suggesting it to be an upstream regulator of these markers. In conclusion, Calycosin stimulates CRC cell apoptosis and inhibits their invasion by acting as SIRT1 activator which induces activation of AMPK-induced inhibition of Akt/mTOR axis.

Combined Supplementation of Nano-Zinc Oxide and Thyme Oil Improves the Nutrient Digestibility and Reproductive Fertility in the Male Californian Rabbits.

The present study aimed to determine the effects of zinc oxide nanoparticles (ZnO-NPs), thyme oil (THO), or their combination on the nutrient digestibility coefficients, reproductive parameters, and some blood metabolites of male Californian rabbits. One hundred rabbits, 29-weeks of age (initial body weight 3.48 ± 0.08 kg) were randomly distributed into four groups, 25 rabbits each. Treatment groups were fed a control diet, a control diet supplemented with ZnO-NPs (100 mg/kg), THO (500 mg/kg), or combination of ZnO-NPs (100 mg/kg) and THO (500 mg/kg). The feeding trial lasted for 35 days. Results showed improvements in dry matter, crude protein, ether extract, and crude fiber in ZnO-NPs, THO, and their combination treated groups compared to those of control. Furthermore, semen volume, sperm motility, vitality, and morphology were significantly improved (p < 0.01) in ZnO-NPs and THO groups rather than the control. Both ZnO-NPs and THO, as either individual or combined treatments significantly improved the serum alanine amino-transferase (ALT), aspartate amino-transferase (AST), urea, and creatinine compared to the control. Moreover, serum concentrations of testosterone were significantly increased in rabbits supplemented with ZnO-NPs, THO, or their combination compared to those of control (p < 0.05). In conclusion, ZnO-NPs, THO, or their combination improved the digestibility of nutrients, liver/ kidney functions, semen characteristics, and testosterone concentration in male rabbits.

Acylated Ghrelin Renders Chemosensitive Ovarian Cancer Cells Resistant to Cisplatin Chemotherapy via Activation of the PI3K/Akt/mTOR Survival Pathway.

This study investigated the effect of acylated synthetic ghrelin (AG) on the survival and proliferation of human chemosensitive ovarian cancer cells (A2780) and explored some mechanisms of action with a focus on the p53 apoptotic pathway and PI3K/Akt and NF-κB survival pathways. Human A2780 ovarian cancer cells were cultured with or without AG treatment in the presence or absence of cisplatin. In some cases, cisplatin+AG-treated cells were pre-incubated either with [D-Lys3]-GHRP-6, a ghrelin receptor antagonist, or with LY294002, a PI3K inhibitor. mRNA of ghrelin receptors(GHS-R1a and GHS-R1b), as well as, protein levels of GHS-R1a, were expressed abundantly in A2780 cells. AG treatment did not affect the mRNA and protein levels of GHS-R1a and GHS-R1b in both control and Cis-treated cells. However, while AG treatment had no effect on control cell viability, it significantly increased cell viability and proliferation and inhibited cell death in Cis-treated cells. In both control and Cis-treated cells, AG treatment significantly increased PI3K/Akt/mTOR signaling and enhanced the nuclear accumulation of NF-κB. Concomitantly, in both control and Cis-treated cells, AG significantly lowered the protein levels of p53, p-p53 (Ser16), PUMA, cytochrome C, and cleaved caspase-3. Interestingly, pre-incubating the cells with either [D-Lys3]-GHRP-6 or LY294002 completely abolished the above-mentioned effect of AG in both control and Cis-treated cells. In conclusion, the findings of this study show that AG promotes cell survival of the OC cells and renders them resistat to Cis therapy, an effect that is mediated by the activation of PI3K/Akt/mTOR and activation of NF-κB, and requires GHS-R1a.

Anti-inflammatory and anti-oxidant properties of Curcuma longa (turmeric) versus Zingiber officinale (ginger) rhizomes in rat adjuvant-induced arthritis.

Turmeric (rich in curcuminoids) and ginger (rich in gingerols and shogaols) rhizomes have been widely used as dietary spices and to treat different diseases in Ayurveda/Chinese medicine since antiquity. Here, we compared the anti-inflammatory/anti-oxidant activity of these two plants in rat adjuvant-induced arthritis (AIA). Both plants (at dose 200 mg/kg body weight) significantly suppressed (but with different degrees) the incidence and severity of arthritis by increasing/decreasing the production of anti-inflammatory/pro-inflammatory cytokines, respectively, and activating the anti-oxidant defence system. The anti-arthritic activity of turmeric exceeded that of ginger and indomethacin (a non-steroidal anti-inflammatory drug), especially when the treatment started from the day of arthritis induction. The percentage of disease recovery was 4.6-8.3% and 10.2% more in turmeric compared with ginger and indomethacin (P < 0.05), respectively. The present study proves the anti-inflammatory/anti-oxidant activity of turmeric over ginger and indomethacin, which may have beneficial effects against rheumatoid arthritis onset/progression as shown in AIA rat model.