Simultaneous determination of methyltestosterone and its metabolite in fish by gas chromatography-mass spectrometry.

Methyltestosterone is one of the banned drugs in aquaculture, and it should be monitored in food-producing animals. 17α-Methyl-5ß-androstane-3α,17ß-diol, as the main metabolite of methyltestosterone in vertebrates, could be used as another marker for controlling the administration of methyltestosterone, due to its high residual concentration and slow elimination rate. In this study, an analytical method based on gas chromatography-mass spectrometry (GC-MS) was developed and validated for the simultaneous determination of methyltestosterone and its main metabolite in fish. After pretreatment by liquid-liquid extraction with n-hexane and solid phase extraction with C18 and NH2 columns, the target analytes in the muscle tissues were extracted and concentrated, and the influence of the sample matrix was eliminated. Then, the prepared samples were separated and detected with GC-MS in the selected ion monitoring (SIM) mode. Methyltestosterone-D3 was chosen as the internal standard for quantitation. After optimization, the limits of detection for methyltestosterone and 17α-methyl-5ß-androstane-3α,17ß-diol were 20 µg kg-1 and 15 µg kg-1, respectively. The limits of quantitation were both 50 µg kg-1. The calibration curves showed good linearity in the concentration range from 50.0 ng mL-1 to 500.0 ng mL-1. The correlation coefficients of methyltestosterone and 17α-methyl-5ß-androstane-3α,17ß-diol were more than 0.9990. The recoveries of the analytes in real samples were in the range of 99.7-116.6% with the relative standard deviation of 5.2-8.3%. The established method could meet the demand for simultaneous detection of methyltestosterone and its major metabolite, and it could be used to provide more information on the abuse of methyltestosterone in food-producing animals.

Targeting Mitochondrial Metabolic Reprogramming as a Potential Approach for Cancer Therapy.

Abnormal energy metabolism is a characteristic of tumor cells, and mitochondria are important components of tumor metabolic reprogramming. Mitochondria have gradually received the attention of scientists due to their important functions, such as providing chemical energy, producing substrates for tumor anabolism, controlling REDOX and calcium homeostasis, participating in the regulation of transcription, and controlling cell death. Based on the concept of reprogramming mitochondrial metabolism, a range of drugs have been developed to target the mitochondria. In this review, we discuss the current progress in mitochondrial metabolic reprogramming and summarized the corresponding treatment options. Finally, we propose mitochondrial inner membrane transporters as new and feasible therapeutic targets.

Chinese medicine formula 'Baipuhuang Keli' inhibits triple-negative breast cancer by hindering DNA damage repair via MAPK/ERK pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Baipuhuang Keli (BPH, constituted by Bai Tou Weng (Pulsatilla chinensis (Bunge) Regel), Pu Gong Ying (Taraxacum mongolicum Hand.-Mazz.), Huang Qin (Scutellaria baicalensis Georgi), Huang Bo (Phellodendron amurense Rupr.)) is a Chinese herbal formula with clearing heat and cooling blood, and removing toxin effects, which is suit for the case of breast cancer. AIM OF THE STUDY: Here, we aim to explore the effects of BPH on triple-negative breast cancer (TNBC) and its potential mechanisms. MATERIALS AND METHODS: In this study, cell viability assay, colony formation assay, soft agar assay, cell proliferation curve assay, and EdU assay were employed to determine the anti-proliferation effect induced by BPH. Cell cycle distribution was detected by flow cytometry. DNA damage in cells treated with BPH was indicated by comet assay, immunofluorescence, and Western Blot. Both the 4T1 orthotopic tumor model and the MDA-MB-231 subcutaneous tumor model were used to assess in vivo effect of BPH (312.5, and 625 mg/kg). The protein expression levels of the DNA damage response (DDR) pathway and the MAPK/ERK pathway were detected by Western Blot. RESULTS: Our results indicated that TNBC cells were more sensitive to BPH than mammary epithelial cells. Cell proliferation of TNBC cells was significantly inhibited by BPH in a dose-dependent manner. Moreover, BPH induced DNA damage in TNBC cells in a concentration and time-dependent manner. DDR of TNBC cells was inhibited by BPH. MAPK/ERK pathway was inhibited in cells treated with BPH, and DNA damage can be reversed while EGF was added to activate MAPK/ERK pathway. The 4T1 orthotopic tumor model and the MDA-MB-231 subcutaneous tumor model further confirmed that BPH inhibited TNBC proliferation via inhibition of DDR and MAPK/ERK pathway in vivo. CONCLUSIONS: Collectively, we proved that BPH is a potential anticancer Chinese herbal formula for TNBC in the manner of in vitro and in vivo experiments.