Ginsenoside Rb1 Suppresses AOM/DSS-induced Colon Carcinogenesis.

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer worldwide. Current treatments, including surgery, radiotherapy, and chemotherapy, are limited by severe side effects and the development of resistance. OBJECTIVE: Therefore, it is important to find additional therapies to combat the problem. Ginsenoside Rb1 is the main active ingredient of ginseng, which is a well-known herb in traditional Chinese medicine. Ginsenoside is reported to play an important role in the prevention and treatment of cancer. METHODS: We established Azoxymethane (AOM)/Dextran sodium sulfate (DSS) colon cancer model based on inflammation, observed the beneficial effect of ginsenoside Rb1, and detected the changes in gut microbiota. RESULTS: Our experimental results showed that ginsenoside Rb1 significantly reduced the levels of TNF-α, IL-6, IL- 17A, IL-33, IL-1ß, and IL-22, increased the level of IL-10, and also changed the gut microbiota composition. These results suggested that ginsenoside Rb1 can be used to prevent inflammation-associated CRC development and may provide an effective therapeutic strategy for CRC by relieving chronic inflammation and restoring the gut microenvironment in the AOM/DSS-induced model of colitis-associated colorectal cancer in mice. CONCLUSION: Ginsenoside Rb1 significantly attenuated AOM/DSS-induced colon carcinogenesis.

L-type Calcium Channels are Involved in Iron-induced Neurotoxicity in Primary Cultured Ventral Mesencephalon Neurons of Rats.

In the present study, we investigated the mechanisms underlying the mediation of iron transport by L-type Ca2+ channels (LTCCs) in primary cultured ventral mesencephalon (VM) neurons from rats. We found that co-treatment with 100 µmol/L FeSO4 and MPP+ (1-methyl-4-phenylpyridinium) significantly increased the production of intracellular reactive oxygen species, decreased the mitochondrial transmembrane potential and increased the caspase-3 activation compared to MPP+ treatment alone. Co-treatment with 500 µmol/L CaCl2 further aggravated the FeSO4-induced neurotoxicity in MPP+-treated VM neurons. Co-treatment with 10 µmol/L isradipine, an LTCC blocker, alleviated the neurotoxicity induced by co-application of FeSO4 and FeSO4/CaCl2. Further studies indicated that MPP+ treatment accelerated the iron influx into VM neurons. In addition, FeSO4 treatment significantly increased the intracellular Ca2+ concentration. These effects were blocked by isradipine. These results suggest that elevated extracellular Ca2+ aggravates iron-induced neurotoxicity. LTCCs mediate iron transport in dopaminergic neurons and this, in turn, results in elevated intracellular Ca2+ and further aggravates iron-induced neurotoxicity.

Isradipine attenuates MPTP-induced dopamine neuron degeneration by inhibiting up-regulation of L-type calcium channels and iron accumulation in the substantia nigra of mice.

The aim of this study is to investigate the effects of L-type calcium channels (LTCCs) on MPTP-induced dopamine (DA) neuron degeneration and iron accumulation in the substantia nigra (SN) of mice. By real-time PCR and western blots, we first quatified expressions of L-type Cav1.2 and Cav1.3 calcium channel α1 subunits in the SN of experimental mice treated with MPTP. We found that the expressions of Cav1.2 and Cav1.3 calcium channel α1 subunits markedly increased after MPTP treatment for 2 and 3 weeks. Secondly, we observed the effects of isradipine, a LTCC antagonist, on MPTP-induced DA neuron degeneration and iron accumulation in the SN. Our results showed that isradipine treatment prevented against MPTP-induced Cav1.2 and Cav1.3 calcium channel α1 subunits up-regulation in the SN. We also found that isradipine prevented against MPTP-induced DA neuron depletion in the SN and partly restored the DA content in the striatum. Moreover, we found that isradipine inhibited the increase of iron positive cells in the SN of the MPTP-treated mice. Finally, we investigated the effects of isradipine on cellular iron accumulation in the dopaminergic MES23.5 cell line. Our studies showed that MPP+ treatment accelerated iron influx in the MES23.5 cells. Treatment with Bayk8644 further aggravated iron accumulation. Treatment with isradipine prevented against MPP+-induced iron influx in the MES23.5 cells. These results suggest that up-regulation of LTCCs may be responsible for the DA neuron degeneration in the MPTP-treated mice, The LTCCs may directly contribute to iron influx into DA neurons, and isradipine may suppress cellular iron accumulation and prevents neurodegeneration.

[Determination of Cr, Ni, Cu, Mn, P, Si, Mo and Ti in high chromium cast iron by inductively coupled plasma atomic emission spectrometry].

The high-chromium cast iron sample was microwave-assisted digested with aqueous regia in a closed vessel. Series standards were prepared with matching Fe matrix and adding Y as internal standard. Line intensities of the prepared standards and the digested sample solutions were determined by inductively coupled plasma atomic emission spectrometry. Accuracy of the proposed method was verified by the analysis of three national standard Materials GSBH 41018, GBW 01120 and GBW 01121, and the results were well agreed with the certification data.