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.

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.

Using the idiosyncratic lipopolysaccharide (LPS)-mediated hepatotoxicity model as a positive control, liver injury induced by Cortex Dictamni aqueous extract (AE) or Cortex Dictamni ethanol extracts (EE) was evaluated. Idiosyncratic hepatotoxicity model was established in rats[Institutional Animal Care and Use Committee (IACUC)-2018-008] by injecting LPS at a dosage of 2.8 mg·kg^-1. Rats were randomly divided into 10 groups. The plasma levels of liver function biomarkers such as alanine transaminase (ALT), aspartate aminotransferase (AST) were measured. Histological changes (HE staining), hepatocellular apoptosis and the content of cytokines of liver were measured. Network pharmacology was used to analyze the relationship between chemical components and immunity in Cortex Dictamni. Compared with the control group, the doses (25, 50 g·kg^-1) of AE or EE had no significant changes in ALT, AST and liver pathology (P>0.05). The doses of 4.2 g·kg^-1 of AE or EE+LPS groups exhibited an elevation in ALT, AST and serum cytokines (P < 0.01). Disorder of liver lobular arrangement and irregular island-like or massive necrosis of liver cells were observed in these groups. Network pharmacology shows that Cortex Dictamni may directly or indirectly participate in the process of immunomodulation. We found that Cortex Dictamni regulated 15 core targets and affected 19 pathways, including apoptosis, TNF-α, NF-kappa B signaling pathways. These results suggest that Cortex Dictamni can induce idiosyncratic hepatotoxicity and the water extract can induce more serious liver injury then ethanol extract of Cortex Dictamni. These findings provide a reference for elucidating the idiosyncratic hepatotoxicity induced by Cortex Dictamni.

The study was conducted to characterize the pharmacokinetics, distribution, metabolism and excretion of CHMFL-FLT3-122 after a single oral dose of 50 mg·kg^-1[¹⁴C] labeled CHMFL-FLT3-122 in rats. Isotope tracing techniques were used to analyze drug concentration and identify the distribution of drugs in tissues and metabolites in biological samples. The experiments were approved by the Animal Ethics Committee of XenoBiotic Laboratories-China, Inc. The absolute bioavailability in male and female rats were 45.83% and 50.92% respectively. The parent drug and its metabolites were extensively distributed in the stomach, intestine, liver and lung, and were eliminated completely in 48 h. The majority of radioactivity was excreted through the feces at 92.34% of the dose with a small fraction through urine at 3.99% of the dose. The parent drug was the most significant circulating component, representing 49.23% and 70.65% over the 0-48 h collection time interval in the plasma of male and female. Two major metabolites, M553 (sulfate conjugate) and M457 (N-dealkyl product), were identified in plasma. Metabolites of CHMFL-FLT3-122, including ten phase Ⅰ and four phase Ⅱ metabolites, were identified. The metabolic pathways of CHMFL-FLT3-122 were proposed as N-dealkylation, oxidation, amide hydrolysis, sulfate conjugation, and glucuronic conjugation.

A LC-MS/MS method for quantification of norfloxacin in human plasma had been developed. This method was applied to the pharmacokinetics study of norfloxacin in the human. The plasma sample was precipitated by methanol and ciprofloxacin was used as the internal standard (IS). Chromatographic separation was performed on a Symmetry® C₁₈ column(100 mm×4.6 mm, 5 μm). Mobile phase contains 0.3% formic acid and 5% methanol in deionized water at a flow rate of 0.45 mL·min^-1. Norfloxacin and ciprofloxacin (IS) were ionized with an ESI source and operated in positive ion mode. The detected ions were m/z 320.3→302.1 (norfloxacin), m/z 332.3→314.1 (ciprofloxacin). This LC-MS/MS method yielded a linearity over the range of 10-1 000 ng·mL^-1 with the lower limit of quantitation (LLOQ) of 10 ng·mL^-1. The intra and inter-assay precisions (RSD%) were within the range of 2.64%-7.23% and the accuracy (RE%) was less than ±5.00%. The pharmacokinetic parameters t_max, C_max, AUC_0-t, and t_1/2 were 1.28±0.364 h, 627±171 ng·mL^-1, 2 938±850 h·ng·mL^-1, and 6.01±1.36 h, respectively. This LC-MS/MS method was proven simple, sensitive, rapid and suitable for pharmacokinetics study of norfloxacin in the human and Approved by the Medical Ethics Committee of Liuzhou Workers' Hospital.

To investigate the effect of Sishen Wan (SSW) on intestinal flora in diarrhea-predominant irritable bowel syndrome (IBS-D) rats and explore the efficacy of this regiment for improving IBS-D, we divided 45 SPF male SD rats randomly into control, disease, SSW, Ershen Wan (ESW) and Wuweizasan (WWZS) groups. The spleen-kidney-yang deficiency type IBS-D rat model was prepared by a composite factor and administered for 14 days. After collecting the feces of the rats, total DNA was extracted from the stool samples. Primers were designed based on the 16S r RNA V3 to V4 regions of the bacteria, and used for high-throughput sequencing with the Illumina Miseq platform. We found that SSW can effectively reduce the diarrhea index (P < 0.05) and reduce the high sensitivity of intestinal tract (P < 0.05) of IBS-D rats. The principal component analysis (PCA), principal co-ordinates analysis (PCoA) and non-metric multidimensional scale analysis (NMDS) based on the Beta diversity distance showed that there were significant differences in the composition of the gut microbiota among the five groups (P < 0.05). The disease group has the lowest in abundance, uniformity and diversity of gut microbiota. Compared with the control group, the disease group showed a significant increase in Proteobacteria, Actinobacteria, Veillonococcus and Mycoplasma (P < 0.05), but a significant reduction in Pleaverella (P < 0.05). Compared with the disease group, SSW administration caused significant reduction in the Proteobacteria and Mycoplasma (P < 0.05), but significant increases of Clostridium, Turicibacter and Romboutsia (P < 0.05). Our study shows that SSW has the potential as a therapeutic regiment for treatment of IBS-D due to partial regulation of the intestinal flora. In addition, there is a synergy between ESW and WWZS.

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.

The molecular identification of Ophiocordyceps sinensis and its adulterants was carried out by real-time fluorescent PCR with TaqMan probe. Genomic DNA was extracted from 100 samples of Ophiocordyceps sinensis and its adulterants. MEGA 7.0 software was used for comparative analysis to define the variable sites between Ophiocordyceps sinensis and its adulterants according to the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA). A set of specific primers and TaqMan probe were designed using Primer Premier 6.0 software, and sensitivity and specificity studies were performed on two different real-time fluorescent PCR systems (Genesig q16 and Bio-Rad CFX96). The sensitivity study showed that the detectable DNA template concentration of Ophiocordyceps sinensis for the real-time fluorescent PCR was 0.016 ng·μL^-1 in the Bio-Rad CFX96 system and 15.527 ng·μL^-1 in the Genesig q16 system, respectively. Meanwhile, this method had good specificity for Ophiocordyceps sinensis on Genesig q16 and Bio-Rad CFX96 systems, so Ophiocordyceps sinensis could be clearly distinguished from Ophiocordyceps nutans, Cordyceps gunnii, Cordyceps militaris, Cordyceps cicadae, Cordyceps liangshanensis, Cordyceps gracilis. Our results indicate that real-time fluorescent PCR with TaqMan probe can be used to accurately identify Ophiocordyceps sinensis from its adulterants. This provides a technical method that has wide applications for market management and quality control of Chinese materia medica.

Protein-protein interaction (PPI) plays an important role in many steps of the human immunodeficiency virus (HIV) life cycle. Targeting these protein-protein interactions, especially the interaction between the virus with host cells, can provide new insights into the development of HIV inhibitors with novel mechanisms of action. Herein, we review the latest discoveries of PPI inhibitors based on the mechanisms of action of various protein-protein interactions with specific research examples.

Ferroptosis is a novel type of regulated cell death with morphology, biochemistry and mechanisms differing from traditional cell death types such as apoptosis, necrosis and pyroptosis. The regulatory mechanisms of ferroptosis mainly involve iron metabolism, amino acid metabolism and lipid metabolism. It has been found that ferroptosis plays a key role in the pathogenesis of diseases including neurodegenerative diseases, malignant tumors and ischemic reperfusion injury. Parkinson's disease (PD) is one of the most common neurodegenerative diseases and its etiology and pathogenesis remains unclear. Recent studies revealed that ferroptosis might be involved in the pathogenesis of PD, as evidenced by high iron content, depletion of reduced form of glutathione and elevated levels of lipid peroxides detectable in the midbrain of PD patients. Both in vitro and in vivo models of PD have shown that some ferroptosis inhibitors have the ability of attenuating the symptoms and one iron chelator is undergoing a clinic trial. We here summarize the mechanisms of ferroptosis and its association with PD, in an effort to suggest potential novel targets for therapies of PD.