The target of celastrol acting on HSP60 against pulmonary fibrosis / 药学学报

Celastrol, extracted from Tripterygium wilfordii, is a natural pentacyclic triterpene compound, which has an anti-pulmonary fibrosis effect. However, its effect, binding targets and regulatory mechanism in pulmonary fibroblasts remain unclear. In this study, we found that celastrol could prevent fibroblast-myofibroblast transformation (FMT) by significantly inhibiting transforming growth factor β1 (TGFβ1)-induced α-smooth muscle actin and type I collagen expression. Previous studies suggested that heat shock protein 60 (HSP60) may be the target of celastrol. This study confirmed the direct interaction between celastrol and HSP60 through cellular thermal shift assay and surface plasmon resonance experiment, and demonstrated that the KD value of celastrol binding to HSP60 was 8.59 μmol·L-1. Further studies showed that knockdown of HSP60 promoted TGFβ1-induced FMT, especially in the medium and low dose TGFβ1 treatment group, and that the anti-FMT effect of celastrol was significantly weakened after HSP60 knockdown. These results indicated that HSP60 was involved in maintaining the resting state of fibroblasts, and the anti-FMT effect of celastrol was dependent on HSP60. Furthermore, the autophagy promotion and antioxidant effects of celastrol were also weakened after HSP60 knockdown. In conclusion, celastrol inhibits FMT by targeting HSP60, thus exerting anti-pulmonary fibrosis function.

Recent advances in microglial activation for treatment of chronic neuropathic pain / 药学学报

As the primary innate immune cells in the central nervous system, microglia can be activated by external noxious stimulus and in turn interact with astroglia and neurons to induce neuroinflammation and facilitate the transmission of pain signals. This response can help the central nervous system adapt to the changes of the internal environment induced by noxious stimulus, leading to the long-term sensitivity of peripheral and central pain nerve conduction pathways and chronic neuropathic pain. Numerous researches found that activation of microglia participated in the occurrence and maintenance of chronic neuropathic pain, and inhibition of microglial activation in the spinal cord or the brain had analgesic effect in animal experiments. Due to the fact that molecular and cellular mechanisms between the activation of microglia and pain remittence are unclear, there are many difficulties in designing of new drugs selectively targeting to the activation of microglia for treatment of chronic neuropathic pain. We review here the research articles on microglia and chronic neuropathic pain, sorting out the relationship between microglia and chronic neuropathic pain, and provide new ideas for the development of new drugs targeting to microglia for the treatment of chronic neuropathic pain.

Advances in JAK2 inhibitors for treatment of myeloproliferative neoplasms / 药学学报

Myeloproliferative neoplasms (MPNs) result from clonal expansion of haematopoietic stem cells and are characterized by abnormal proliferation of myeloid lineage cells in the bone marrow. Sustained activation of JAK-STAT signaling pathway due to JAK2 phosphorylation is an important cause of MPNs, and mutation of JAK2 kinase can keep it in a state of continuous phosphorylation. The most typical mutation in JAK2 is a site mutation of V617F in the pseudokinase domain. The JAK2V617F-activating mutation is highly prevalent in MPNs, with frequencies estimated at approximately 95% in polycythaemia vera (PV) and 50% in primary myelofibrosis (PMF) and essential thrombocytosis (ET) patients. It is now clear that JAK2 is an important target for treatment of MPNs. Inhibiting aberrant activation of the JAK2-STAT signaling pathway has become a popular trend in research for effective treatment of MPNs. This review summarizes the research progress in developing JAK2 inhibitors for treatment of MPNs in recent years, including the new discoveries of the biological functions of JAK2, the relationship between JAK2 and MPN, and the status of development of JAK2 small molecule inhibitors.

Research progress of JAK-3 kinase and its inhibitors / 药学学报

JAK-3, a member of the Janus kinase family, is a protein tyrosine kinase, which plays an important role in the JAK-STAT signaling pathway. Previous studies showed that regulation of JAK-3's activity plays a crucial role in the treatment of diseases such as rheumatoid arthritis. Many reports have been published with a focus on selective JAK-3 inhibitors, some of which showed excellent JAK-3 selectivity and inhibitory activities. Among the JAK-3 inhibitors reported, tofacitinib has satisfactory therapeutic benefits in the clinical trials, and has been approved for treatment of patients with rheumatoid arthritis. However, some JAK-3 inhibitors exhibited moderate to severe side effects, which need to be controlled by drug improvement. In order to pave the way for improvement of current JAK-3 inhibitors and development of new JAK-3 inhibitors, we provide an outline of the structure of JAK-3 and strategies in development of its inhibitors.

Recent development of non-steroidal anti-inflammatory drugs on the neuro-inflammation of Alzheimer's disease / 药学学报

Neuropathological, clinical epidemiology and animal models studies provide clear evidence for the activation of neuroinflammation in Alzheimer's disease (AD), and long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) is linked with reduced risk to develop the disease. But the clinical trials got a negative outcome with traditional NSAIDs treating AD. The therapeutic effects of NSAIDs on Alzheimer's disease are still not clear based on the present research. Profound study for anti-inflammatory mechanisms and standardized clinical trials are needed. As cause and effect relationships between neuroinflammation and AD are being worked out, the challenge is how to realize the effect of traditional NSAIDs on treating AD.

High throughput screening for glutathione S-transferase inhibitors / 药学学报

To identify the inhibitor of glutathione S-transferase (GST), a high-throughput screening method was established in a 384-well microplate with total 35 microL volume, and the absorbance at 340 nm is detected. The concentrations of substrates, CDNB and GST were determined by chromatometry. The optimal enzyme kinetics reaction time and temperature are 2 h and 30 degrees C , respectively. The established model was evaluated by NaOCl, a known GST inhibitor, and the parameter Z' was 0.77, which showed a high feasibility and stability of the assay. A total of 31,098 compounds were screened, of which 4 compounds were shown to inhibit GST activity, high inhibiting activity for their IC50 of GST inhibition was 3.94, 4.05, 74.85, and 77.41 mg x L(-1), separately. The results indicated that the colorimetric method by using CDNB and GSH as substrate is stable, sensitive, reproducible and also suitable for high throughput screening.

Identification of ligands for human LOX-1 through fluorescence polarization-based high throughput screening / 药学学报

<p><b>AIM</b>To develop a fluorescence polarization-based high throughput screening and identify ligands for human Lectin-like oxidized low-density lipoprotein receptor-1 (hLOX-1).</p><p><b>METHODS</b>Sequential ultracentrifugation at 4 degrees C from normolipidemic fasting volunteers to obtain low density lipoprotein (LDL), which was modified by CuSO4 (5 micromol x L(-1)) at 37 degrees C for 24 h. The assay was based on the interaction between receptor and ligand, and hLOX-1 was labeled by FITC and bound to its specific ligand, oxLDL. Different reaction time and DMSO concentration were optimized to determine the stability and tolerance of fluorescence polarization (FP) assay. 3 200 compounds were screened in black 384-well microplate by FP-based competitive displacement assay, at excitation filter of 485 nm and emission filter of 530 nm. Z' was used to assess the assay quality.</p><p><b>RESULTS</b>The FP-based HTS was formatted in a 384-well microplate with a Z' factor of 0. 75, and three active compounds for hLOX-1 were identified with IC50 below 40 micromol x L(-1) from total 3 200 compounds.</p><p><b>CONCLUSION</b>The results indicated that the fluorescence polarization assay is stable, sensitive, reproducible and well suited for high throughput screening efforts.</p>

Expression of HBcAg in eukaryotic cells by retroviral vector mediated gene transfer / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To construct recombinant retroviral vector expressing HBcAg in eukaryotic cells.</p><p><b>METHODS</b>The HBV core gene fragment was amplified by using PCR from pADR which contains complement nucleotide sequence of HBV subtype adr and cloned into retroviral expression plasmid pLXSN, then transfected into packing cell (PT67) with lipofec AMINE. After 2-3 weeks selection with G418, large colonies were isolated and transferred to individual plates. Virus-containing medium was collected and used to infect NIH3T3, EL4 and mouse bone marrow derived dendritic cells(DC). DNA was extracted from infected cells and tested by PCR. Indirect immunofluorescence and FACS were used to detect the expression of HBcAg. Cell mediated immunity of immunized C57BL/6 mice with transduced DC was analyzed.</p><p><b>RESULTS</b>The insertion of HBV core gene fragment in the recombinant retroviral plasmid was confirmed by PCR as well as enzyme digestion with EcoR1 and BamH2. The viral titer reached 3 x 10(5) CFU/ml. The result of PCR showed that the HBV core gene had been integrated into the genome of infected NIH3T3 cells. Indirect immunofluorescence and FACS analysis showed that HBcAg had been expressed in these cells. HBcAg specific CTL responses could be generated in mice immunized with retrovirus transduced DC.</p><p><b>CONCLUSIONS</b>HBV core gene had been integrated into eukaryotic cells with retroviral vector and target gene had been expressed efficiently. These results may have some impact on gene therapy of chronic hepatitis B.</p>