Microbiota-derived metabolites in colorectal cancer patients in preoperative period.

OBJECTIVE: Short-chain fatty acids (SCFAs) are microbial derived metabolites, which have multiple beneficial properties. The amount of SCFAs depends on several factors, such as age, diet (mainly intake of dietary fiber), and overall health condition. The normal proportion between SCFAs is 3:1:1 for acetate, proprionate and butyrate, respectively. In colorectal cancer (CRC) patients, microbiota alterations have been shown. Consequently, metabolome within the gut might change to a large extent. Therefore, the aim of this study was to analyse the content of SCFAs and the proportion between SCFAs in the stool obtained from CRC patients in preoperative period. PATIENTS AND METHODS: This study included 15 patients with CRC in preoperative period. The stool samples were taken and stored at -80°C in the Fahrenheit Biobank BBMRI.pl, Medical University of Gdansk, Poland. The analysis of SCFAs from stool samples was conducted by means of gas chromatography. RESULTS: This study included mainly males (66.67%, n=10). In all patients, there was abnormal proportion between SCFAs. The extremely higher concentration of butyrate was noted in 2 samples (13.33%) compared to the rest of patients. However, based on normal proportion between SCFAs, the results <1 for butyrate were noted in 93.33% of patients. CONCLUSIONS: SCFAs pool is altered in CRC patients, among others characterized by low level of butyrate. It should be considered to administer butyrate supplementation to CRC patients especially prior to surgery to support an appropriate preparation to this treatment.

The wine polyphenol resveratrol modulates autophagy and induces apoptosis in MOLT-4 and HL-60 human leukemia cells.

Resveratrol is a naturally occurring polyphenolic compound present in many plant species and wine. It possesses a wide range of beneficial biological properties including anticancer activity. Resveratrol has been demonstrated to induce both autophagy and apoptosis in several human cancer cell lines. The aim of this study was to investigate whether resveratrol modulates autophagy and apoptosis in MOLT-4 human lymphoblastic leukemia and HL-60 human promyelocytic leukemia cells. Cell viability was evaluated by the neutral red uptake assay. Cell cycle distribution, phosphatidylserine externalization, caspase-3 activation, changes of the mitochondrial membrane potential, intracellular production of reactive oxygen species were evaluated by flow cytometry. LC3-I to LC3-II conversion was examined based on Western blotting and immunofluorescence analyses. The level of p62/SQSTM1 protein and PARP1 cleavage were analyzed by Western blotting. The DNA degradation was assessed by gel electrophoresis. We found that resveratrol is able to modulate autophagy in MOLT-4 and HL-60 cells, as evidenced by the detection of an increased level of LC3-II and p62/SQSTM1 proteins. Moreover, resveratrol induced apoptosis in both cell lines which was associated with phosphatidylserine externalization, disruption of the mitochondrial membrane potential, caspase-3 activation, internucleosomal DNA fragmentation, PARP1 cleavage, chromatin condensation, and fragmentation of cell nuclei. The present study provides evidence that resveratrol can act as an autophagy modulator as well as an apoptosis inducer in MOLT-4 and HL-60 human leukemia cells. Our findings imply that resveratrol can be a promising chemotherapeutic agent in the treatment of leukemia.

3-Fluoromethcathinone, a structural analog of mephedrone, inhibits growth and induces cell cycle arrest in HT22 mouse hippocampal cells.

Recently, the abuse of recreational drugs has become an important problem in many countries. Among these psychoactive substances are synthetic cathinones, a group of compounds derived from the alkaloid cathinone, that have gained widespread popularity. Many cathinones have demonstrated neurotoxic effects. The aim of this study was to examine the effects of 3-fluoromethcathinone, a structural analog of mephedrone, on HT22 mouse hippocampal cells. Cell viability was assessed using the sulforhodamine B assay. Flow cytometry was used to study the cell cycle distribution. We found that 3-fluoromethcathinone inhibits growth of HT22 cells. Our results also revealed that it induces G0/G1-phase cell cycle arrest. To our knowledge, this is the first study to demonstrate the cytotoxic action of 3-fluoromethcathinone. Our findings suggest that abuse of this cathinone derivative may not be without risk.

Pterostilbene induces accumulation of autophagic vacuoles followed by cell death in HL60 human leukemia cells.

Pterostilbene, a naturally occurring structural analog of resveratrol, has been reported to exert antiproliferative and proapoptotic effects in various cancer types. Recently, it has been demonstrated to induce both autophagy and apoptosis in human bladder and breast cancer cell lines. The aim of this study was to evaluate the effects of pterostilbene on HL60 human leukemia cells. Cell morphology was examined using confocal and electron microscopy. Cell viability was determined by MTT, neutral red uptake and trypan blue exclusion assays. LC3 processing was studied based on Western blotting and immunofluorescence analyses. Flow cytometry was used to study cell cycle distribution, phosphatidylserine externalization, caspase activation, disruption of mitochondrial membrane potential and intracellular production of reactive oxygen species. DNA degradation was examined by gel electrophoresis. We found that treatment of HL60 cells with pterostilbene at the IC90 concentration resulted in the G0/G1 cell cycle arrest. Pterostilbene induced conversion of cytosolic LC3-I to membrane-bound LC3-II and accumulation of large LC3-positive vacuolar structures. Pterostilbene also led to phosphatidylserine externalization, internucleosomal DNA fragmentation, caspase activation and disruption of mitochondrial membrane potential. Moreover, it did not induce oxidative stress. Our results suggest that pterostilbene induces accumulation of autophagic vacuoles followed by cell death in HL60 cells.