Genotoxic and cytotoxic evaluation of venlafaxine in an acute and a subchronic assay in mouse

The present research was made to determine the micronuclei and cytotoxic capacity of the antidepressant venlafaxine in an in vivo acute and subchronic assays in mouse. In the first study, we administered once 5, 50, and 250 mg/kg of the drug, and included a negative and a daunorubicin treated group. Observations were daily made during four days. The subchronic assay lasted 5 weeks with daily administration of venlafaxine (1, 5, and 10 mg/kg) plus a negative and an imipramine administered groups. Observations were made each week. In the first assay results showed no micronucleated polychromatic erythrocytes (MNPE) increase, except with the high dose at 72 h. The strongest cytotoxic effect was found with 250 mg/kg at 72 h (a 51% cytotoxic effect in comparison with the mean control level). In the subchronic assay no MNPE increase was found; however, with the highest dose a significant increase of micronucleated normochromatic erythrocytes was observed in the last three weeks (a mean of 51% respect to the mean control value). A cytotoxic effect with the two high doses in the last two weeks was observed (a polychromatic erythrocyte mean decrease of 52% respect to the mean control value). Results suggest caution with venlafaxine.

Cytotoxic effect of hydroalcoholic extract of Cota tinctoria (L.) J.Gay on AGS and Hep-G2 cancer cell lines

Cota tinctoria is a medicinal plant which has been used for management of cancer in folk medicine of various regions. The aim of present study is to investigate cytotoxic activity of different concentrations of hydroalcoholic extract of C. tinctoria flowers on gastric (AGS) and liver (Hep-G2) cancer cell lines as well as Human Natural GUM fibroblast (HUGU) cells. Cell mortality rates were examined after 24, 48 and 72 h incubations using the MTT assay. IC50 of extract on AGS cells after 24, 48 and 72h was 1.46, 1.29 and 1.14 µg/mL respectively. The extract demonstrated IC50 of 5.15, 3.92 and 2.89 µg/mL on Hep-G2 cells after 24, 48 and 72 h respectively. No cytotoxic effect was detected on HUGU (Human Natural GUM fibroblast) cells. C. tinctoria seems to have a promising potential to be considered as a source for anticancer drug discovery. However, more experimental and clinical studies are required.

The Effect of Fatty Acids on Ciprofloxacin Cytotoxic Activity in Prostate Cancer Cell Lines. Does Lipid Component Enhance Anticancer Ciprofloxacin Potential?

Purpose: To assess cytotoxic effect of ciprofloxacin conjugates with fatty acids on prostate cancer cells (LNCaP and DU-145) with different hormone sensitivity, based on previous promising results from the PC3 cells. Methods: Cytotoxicity were estimated using MTT and LDH tests, whereas its mechanisms were estimated by apoptosis and IL-6 assays. The intensity of proteins involved in lipid metabolism was determined using ML-CS assay. Results: The hormone insensitive DU-145 cells were more vulnerable than the hormone sensitive LNCaP cells. The IC50 values for oleic (4), elaidic (5) and docosahexaenoic acid (8) conjugates were 20.2 µM, 17.8 µM and 16.5 µM, respectively, in DU-145 cells, whereas in LNCaP cells IC50 exceeded 20 µM. The strong conjugate cytotoxicity was confirmed in the LDH test, the highest (70.8%) for compound (5) and 64.2% for compound (8) in DU-145 cells. This effect was weaker for LNCaP cells (around 60%). The cytotoxic effect of unconjugated ciprofloxacin and fatty acids was weaker. The early apoptosis was predominant in LNCaP while in DU-145 cells both early and late apoptosis was induced. The tested conjugates decreased IL-6 release in both cancer cell lines by almost 50%. Proteomic analysis indicated influence of the ciprofloxacin conjugates on lipid metabolic proteins in prostatic cancer. Conclusion: Our findings suggested the cytotoxic potential of ciprofloxacin conjugates with reduction in proteins involved in prostate cancer progress.

The Mechanisms of GPR55 Receptor Functonal Selectivity

The objective of the project is to establish the mechanisms of multidirectional signal transmission through the same G-protein coupled receptor GPR55. Using the CRISPR-Cas9 system, clones of the MDA-MB-231 line knockout for the GPR55 (3 clones) and CB2 (CNR2 - 6 clones) receptor genes were obtained. On clones of the MDA-MB-231 line with a knockout CB2 receptor, the cytotoxic activity of the pro-apoptotic ligand docosahexaenoyldopamine (DHA-DA) did not change or slightly increased, while the pro-proliferative activity of the most active synthetic ligand of the GPR55 receptor (ML-184) completely disappeared. On the original line MDA-MB-231, the stimulatory effect of ML-184 is removed by the CB2 receptor blocker, but not by GPR55. At the same time, the stimulating effect of ML-184 is practically not manifested on cell lines knockout at the GPR55 receptor. Thus, it can be confidently assumed that when proliferation is stimulated with the participation of the GPR55 receptor, a signal is transmitted from the CB2 receptor to the GPR55 receptor due to the formation of a heterodimer. GPR18 and TRPV1 receptors are additionally involved in the implementation of the cytotoxic effect of DHA-DA, while the CB1 receptor is not involved. In the implementation of the cytotoxic action of DHA-DA, the predominant participation of one of the Ga subunits was not found, but the Ga13 subunit plays a decisive role in the implementation of the proproliferative action. The Gaq subunit is also important, although to a lesser extent than Ga13.

Glucose Limitation Sensitizes Cancer Cells to Selenite-Induced Cytotoxicity via SLC7A11-Mediated Redox Collapse

Combination of intermittent fasting and chemotherapy has been drawn an increasing attention because of the encouraging efficacy. In this study, we evaluated the anti-cancer effect of combination of glucose limitation and selenite (Se), a representative inorganic form of selenium, that is preferentially accumulated in tumors. Results showed that cytotoxic effect of selenite on cancer cells, but not on normal cells, was significantly enhanced in response to the combination of selenite and glucose limitation. Furthermore, in vivo therapeutic efficacy of combining selenite with fasting was dramatically improved in xenograft models of lung and colon cancer. Mechanistically, we found that SLC7A11 expression in cancer cells was up-regulated by selenite both in vitro and in vivo. The elevated SLC7A11 led to cystine accumulation, NADPH depletion and the conversion of cystine to cysteine inhibition, which in turn boosted selenite-mediated reactive oxygen species (ROS), followed by enhancement of selenite-mediated cytotoxic effect. The findings of the present study provide an effective and practical approach for increasing the therapeutic window of selenite and imply that combination of selenite and fasting holds promising potential to be developed a clinically useful regimen for treating certain types of cancer.

Antibacterial Profile in vitro and in vivo of New 1,4-Naphthoquinones Tethered to 1,2,3-1H-Triazoles against the Planktonic Growth of Streptococcus mutans

The cariogenic processes are mainly caused by the bacterium Streptococcus mutans (S. mutans) and consist of the demineralization of the tooth that occurs when the acid production overcomes the natural repair or if a problem occurs in the last one. In this work, we performed the synthesis of twenty-one 1,4-naphthoquinones tethered to 1,2,3-1H-triazoles (8a-8k and 9a-9j), antibacterial evaluation against the S. mutans in vitro and the acute toxicity of the better ones in vivo. We observed strong inhibition results in the disc diffusion test ranging, the halos of inhibitions, from 18.66 (± 0.57) to 29 (± 2.64) mm, and good values in the minimum inhibitory concentration (5 to 50 μg), for the compounds 9e, 9h, 9i and 9j. Furthermore, they do not have a cytotoxic effect at the concentrations tested. Besides that, in the in vivo test, they show some slight alteration in the histopathological analyses and the biochemistry. Thus, we found four potential candidates to become instruments for the treatment of cavities.

Cytotoxicity Effect and Morphological Changes of Chrysanthemum Morifolium Methanolic Extract against Chronic Myeloid Leukaemia K-562 Cell Line

Chrysanthemum morifolium, also known as “Bunga kekwa” in Malaysia, has various benefits and widely used in Chinese herbal medicines. The plant extract was reported to have significant biological activities, such as anti-inflammation, anti-tumour, anti-oxidant, and anti-cancer. Nonetheless, its anti-cancer potential on chronic myeloid leukaemia has remained elusive. The main goal of this study is to evaluate the cytotoxic effect of C.morifolium buds and flowers in methanolic extracts on chronic myeloid leukaemia malignancy K-562 cell lines. The bud and flower of C.morifolium were macerated for 72 hours in 100% methanol then were concentrated under reduced pressure using a rotary evaporator and oven-dried to obtain crude extracts. K-562 cells were treated with six different concentrations 400, 200, 100, 50, 25, and 12.5 µg/ml and incubated for 24, 48 and 72 hours. The in vitro cytotoxic activity was measured using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) test and was quantified using a microplate reader at 570 nm. Acridine orange and propidium iodide (AO/PI) staining were used to assess morphological alterations. MTT assays results showed moderate toxicity of both extracts. The lowest maximal half inhibitory concentration (IC50) value were observed at 72 hours of incubation; 182 ± 4.04 ug/ml for BM and 161 ± 7.88 ug/ml for flower extract (FM). However, there was a significantly different IC50 value (p<0.05) between the incubation periods of both treatments where the IC50 value at 24 hours was 301.33 ± 8.51 ug/ml 301 µg/ml in BM, 216 ± 10.79 ug/ml 216 µg/ml in FM and at 48 hours was 227 ± 12.25 ug/ml 227 µg/ml in bud extract (BM), 174 ± 11.92 ug/ml 174 µg/ml in FM. The morphological changes evidence was shown in AO/PI staining by the appearance of a mixed population of cells; early apoptosis, late apoptosis and necrotic cells. These findings suggested that methanolic C.morifolium extracts showed moderate cytotoxic effect on chronic myeloid leukaemia K-562 cells. Further study needed to identify the mode and mechanism of cell death in K-562 cells treated with the C.morifolium extracts.