Adaptation to hypoxia of the plateau environment has been a focus of scientific research in decades. The geographical distributions of such living environment include the Qinghai-Tibet Plateau, Andean Plateau in South America and Ethiopian Plateau. Over the past century, the unique features of physiological adaptation to high-altitude chronic hypoxia have been documented scientifically. The genetic studies of hypoxic adaptation in the past decade have revealed genetic bases of human high-altitude adaptation, with a close relationship to the hypoxia inducible factor (HIF) pathway and hypoxia response elements (HREs). Interestingly, the genetic pattern of adaptation to hypoxia is not the same among the three plateau populations. Tibetan has developed the best high-altitude adaptation, with modification of the HIF pathway as the key genetic element. Due to the wide range of HIF pathways, HIFs could regulate hundreds of downstream genes and are closely related to various diseases such as cancer, inflammation, ischemia, acute organ damage and infection, etc. The treatment researches of these diseases through HIFs-related regulations have led to the development of stabilizers and inhibitors of HIF pathway. We review here the adaptive responses of the three plateau populations to the hypoxic environment, and the genetic mechanism of HIF and HREs in the different ethnic high-altitude populations. Classes of HIF inhibitors, such as PI3K and/or mammalian target of rapamycin (mTOR) inhibitors, DNA-binding inhibitors, histone deacetylase inhibitors, heat-shock protein 90 inhibitors, cardiac glycosides, transcription inhibitors, topoisomerase inhibitors, and HIF activators including 2-OG mimics, Fe²⁺ chelators, prolyl hydroxylase (PHD) active-site blockers and CUL2 deneddylators have been presented with the drug examples. In addition, the top 3 chemical-disease and chemical-gene (protein) co-occurrences have been presented from the Pubmed literature search. The review could serve as references for research of hypoxia adaptation and HIF-related diseases.

To expand an efficient strategy for the conversion of antibacterial activity of fluoroquinolones into an antitumor activity, sixteen new compounds, 1-cyclopropyl-6-fluoro-7-(4-methyl-piperazin-1-yl)-3-(5-arylidene-thiazol-4(5H)-one-2-yl)-quinolon-4(1H)-ones (7a-7p), were designed and synthesized with a thiazolone ring and an arylidene moiety as an isostere and modified group, respectively, from ciprofloxacin. Their structures were characterized by elemental analysis and spectral data. The in vitro antitumor activity of the synthesized compounds were measured using Hep-3B, Capan-1 and HL60 cell lines and were found to be more potent than ciprofloxacin. Meanwhile, the SAR revealed that the halogenated phenyl compounds such as fluorophenyl (7h, 7i), chlorophenyl (7j, 7k) or bromophenyl compounds (7l, 7m), and aromatic heterocyclic substitution such as furyl (6n) or pyridyl compounds (6o, 6p) displayed better activity than the control compounds, especially the IC₅₀ values of pyridyl compounds 6o and 6p against Capan-1 cell growth was comparable to doxorubicin. Thus, an arylidene-modified thiazolone scaffold as the replacement of the C-3 carboxylic acid group appears to be an alternative route for an improved antitumor activity of fluoroquinolones.

Ellagic acid is ubiquitous in plants and is considered as a potential candidate for antioxidant and antineoplastic drugs. However, ellagic acid has poor solubility and precipitates easily even after initial solubilization. Improvement of its bioavailability has been a concern of pharmaceutical industry. It was found that storage in Sanlejiang oral liquid at low temperature keeps its stability. Ellagic acid is anomalous in a way that is easily soluble at low temperatures but precipitates at high temperatures. In order to reveal the mechanism of this phenomenon and develop precipitation prevention and control strategies, ellagic acid in Sanlejiang oral liquid was stored at high, medium and low temperatures for three months. The changes of composition and phase state of the whole system during storage were systematically tracked and studied by means of precipitation amount or morphology, HPLC chemical profile of supernatant versus precipitates, and comprehensive characterization of physical phase state. The results show that the amount of precipitation at low temperature is only 1/3 of that at normal room temperature. As the temperature rises, the sedimentation increases sharply. HPLC analyses of supernatant versus precipitates revealed that ellagic acid precipitation originated from two ways:chemical degradation and physical deposition. The chemical sedimentation is related to the hydrolysis of tannins under acidic condition, forming chebulagic acid and corilagin. Physical sedimentation is related to the decrease of the association degree and viscosity of polyphenol colloids when temperature rises. This study elucidated the stability mechanism of ellagic acid in liquid preparations of TCM, and provided the mechanistic basis for efficient utilization and solution prepartion of ellagic acid.

In this study, black phosphorus quantum dots (BPQDs)-loaded liposomes (liposome-BPQDs) were prepared to explore physicochemical properties and photothermal effects on cervical cancer cells. BPQDs were fabricated by ultrasonic method. Liposome-BPQDs were prepared by thin film dispersion. Surface morphology, particle size, zeta potential and Raman spectra of liposome-BPQDs were characterized. The cytotoxicity of the liposome-BPQDs against human cervical cancer cells (HeLa) was examined by CCK-8 assay. Confocal laser scanning microscope (CLSM) and fluorescence microscopy were used to observe the uptake and apoptosis of HeLa cells. The results indicated that liposome-BPQDs were ellipsoidal or spherical under scanning electron microscope, TEM observation showed liposome-BPQDs were about 90-110 nm in diameter. The particle size measurements showed liposome-BPQDs were (104.2±0.35) nm in diameter, and zeta potential were examined to be (-11.3±3.01) mV. The encapsulation efficiency was (84.40±2.13)%.Under natural conditions with outdoor ventilation, temperature range of 25℃-34℃ and relative humidity of 80%-82%, the photothermal effects of liposome-BPQDs was better and the degradation denaturation of liposome-BPQDs were slower than those of BPQDs. The results also reflected that liposome-BPQDs could be uptaken by HeLa cells easily. After near-infrared laser irradiation, the mortality of HeLa cells rise significantly when the amount of BPQDs reach 20 μg·mL^-1. In summary, liposome-BPQDs with high stability exhibited good photothermal effects, which can be expected to be applied to photothermal therapy of cervical carcinoma.

The chemical constituents of Litsea coreana were investigated using chromatographic methods, including column chromatography on silica gel, MCI, and semi-preparation HPLC. Two compounds were isolated and identified as hawktealignan A (1) and cinnamophilin (2) by NMR analyses as well as their physical and chemical properties. Compound 1 is a new lignan and compound 2 was isolated from this plant for the first time.

Chemotherapy plays an essential role in controlling tumor growth and progression. However, long-term use of chemotherapeutic drugs usually results in drug resistance in tumor cells, leading to treatment failure and disease progression. The mechanism of tumor resistance to chemotherapy and the strategy of prevention or reversal of such resistance have always been hot issues in cancer therapy research. Exosomes are small spherical vesicles secreted by cells with a diameter of 40-100 nm. They carry a variety of bioactive small molecules (including DNA, ncRNA, RNA, and proteins) and participate in regulation of cell microenvironment, thereby affecting a variety of physiological and pathological activities in the body. In recent years, studies have shown that exosomes play an important role in cancer cell resistance to chemotherapy, metastasis, and immune escape. This article reviews the role and mechanism of exosomes in the development of drug resistance in tumors, and aims to provide new ideas for the prevention or treatment of tumor resistance.

The blood brain barrier can selectively block the uptake of xenobiotics from peripheral blood into the brain. Although this is important for maintaining the stability of the brain environment and normal function of the central nervous system, it presents a challenge for delivery of therapeutic drugs to the brain. Passive brain-targeting drug carrier is able to increase the drug concentration in the brain by enhancing the affinity to blood-brain barrier and/or inhibiting the efflux absorbed drug via P-glycoprotein. The active brain-targeting drug carrier can be obtained by linking specific ligands or antibodies onto passive target carriers to achieve precise delivery of drugs to the brain. Dual targeting drug carriers obtained by combining tumor cell targeting with brain targeting have shown their advantages for treatment of brain tumors. The targeted drug delivery to brain will provide a unique manner for the treatment of brain diseases such as Alzheimer's, Parkinson's, brain tumors, and stroke. Among the drug delivery systems of passive brain-targeting, active brain-targeting and dual brain-targeting, we evaluated the strategies to improve brain drug delivery efficiency, such as by reducing carrier size, opening tight junctions between cells at the blood-brain barrier, incorporating hydrophilic groups on the surface of the carrier, and alternative intranasal drug administration.

In this paper, three methods, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and X-ray powder diffraction (PXRD), were used to characterize the structure of Palbociclib. The form-B crystal mixed in with form-A crystal, the effective form of Palbociclib, was quantitated by the single peak method (peak area method and peak height method) using X-ray powder diffraction. While the qualitative identification by DSC was not clear, SEM and PXRD quickly and effectively identified two types of crystal. The standard curve equations established by the peak area method and the peak height method are:y=0.842 75x-0.001 21 and y=0.909 64x-0.002 32. This suggests that the linear relationship of peak area method is better than that of peak height method (R²=0.986 17 and R²=0.985 83). The sensitivity of the peak area method (LOD=1.17%, LOQ=3.92%) are higher than the peak height method (LOD=1.19%, LOQ=3.97%). The methods from this study can be used to identify and quantify palbociclib form-A and form-B crystal rapidly.

This study explores the antidepressant mechanism of Radix Bupleuri-Radix Paeoniae Alba herb pair and the core role in Xiaoyaosan. The behavioral indicators were used to observe the effects of herb pair, Xiaoyaosan, and a negative control (Xiaoyaosan remove Radix Bupleuri-Radix Paeoniae Alba) on CUMS rats. The body weight, number of crossing and rearing, sugar preference rate were significantly decreased (P < 0.001) and the immobility time of forced swimming test was significantly prolonged (P < 0.01) in the model group. Radix Bupleuri-Radix Paeoniae Alba herb pair has significant antidepressant effect, with the number of crossing in low dose group similar to Xiaoyaosan, while the number of rearing and the sucrose preference rate in high dose group are equivalent to Xiaoyaosan, and the immobility time in high and low-doses group are better than Xiaoyaosan. Animal experimentation was approved according to the Committee on the Ethics of Animal Experiments of Shanxi University. Metabonomics results showed 15 biomarkers related to depression, whereas administering Xiaoyaosan or the herb pair can ameliorate 12 or 8 metabolites respectively, compared to the negative control, which can only ameliorate 6 metabolites. The metabolic pathway analysis showed 5 depression-related pathways. The herb pair and Xiaoyaosan exerted antidepressant effects through common 4 metabolic pathways, while the negative control only exerted effects through 3. In summary, behavioral, metabolomics and metabolic pathway analysis revealed that Radix Bupleuri-Radix Paeoniae Alba plays an important role in the biological effect of Xiaoyaosan.

The purpose of this study is to further explore the effects of SI-4650, a newly discovered small molecule inhibitor of spermine oxidase (SMO) in our laboratory, on proliferation and migration of human osteosarcoma 143B cells and its underlying molecular mechanism. Chemiluminescence and high performance liquid chromatograph were used to analyze the effect of SI-4650 on SMO activity in 143B cells. DCFH-DA-staining/FCM was used to analyze the accumulation of cellular reactive oxygen species (ROS), whereas MTT and FCM were used to detect proliferation and cell cycle. Transwell culture and Western blot were used to analyze the expression levels of migration-related proteins. PI/FITC-Annexin V/FCM, fluorescence microscopy and Western blot were used to analyze apoptosis and autophagy. Our results showed that SI-4650 could significantly decrease SMO activity, inhibit cell proliferation or migration, and induce a S-phase cell cycle arrest in 143B human osteosarcoma cells. The mechanism may be related to interfering with polyamine metabolism, activating mitochondrial-mediated apoptosis and causing autophagic death. These results suggest that SI-4650 has the potential for clinical use in treatment of osteosarcoma.