Homo- or heterodimeric compounds that affect dimeric protein function through interaction between monomeric moieties and protein subunits can serve as valuable sources of potent and selective drug candidates. Here, we screened an in-house dimeric natural product collection, and panepocyclinol A (PecA) emerged as a selective and potent STAT3 inhibitor with profound anti-tumor efficacy. Through cross-linking C712/C718 residues in separate STAT3 monomers with two distinct Michael receptors, PecA inhibits STAT3 DNA binding affinity and transcription activity. Molecular dynamics simulation reveals the key conformation changes of STAT3 dimers upon the di-covalent binding with PecA that abolishes its DNA interactions. Furthermore, PecA exhibits high efficacy against anaplastic large T cell lymphoma in vitro and in vivo, especially those with constitutively activated STAT3 or STAT3^Y640F. In summary, our study describes a distinct and effective di-covalent modification for the dimeric compound PecA to disrupt STAT3 function.

Objective To observe the changes on the neurogenic inflammation-related factors in the dura mater of the rat model of migraine and investigate the possible mechanism of the pain of migraine.Methods SD rats were randomly divided into stimulation group ( n = 32 ) and sham group ( n = 32 ).Unilateral trigeminal ganglion was stimulated to induce migraine for rats in the stimulation group. Rats in the sham group were subjected to sham surgery. The levels of calcitonin gene-related peptide (CGRP) in the blood of jugular vein in the stimulation side were measured by radioimmunoassay. The levels of histamine in peripheral blood and prostaglandin E2 (PGE2 ) in the dura mater were determined by enzyme-linked immunosorbent assay (ELISA). The number of mast cells and percentage of their degranulation in the dura mater were determined under a microscope after toluidine blue staining. Cyclooxygenase 2 (COX-2)expression in the dura mater was evaluated by immunohistochemical staining and western blot analysis. Results In the stimulation group, the level of CGRP in the ipsilateral jugular vein was (82. 84 ± 16. 24)pg/ml and in the sham group was (59. 20 ±11.66) pg/ml (t = -3.34, P ＜ 0. 05 ). The level of histamine in the ipsilateral jugular vein was ( 11.59 ± 1.20) ng/ml and in the sham group was (9. 87 ±0. 88) ng/ml (t = - 3. 27, P ＜ 0. 05). The number of mast cells in the dura mater decreased from 15.46 ± 2. 40 in the stimulation group to 11.63 ± 1.67 in the sham group ( t = 3.71, P ＜ 0. 05 ). Degranulation of mast cells in the dura mater significantly increased from 14. 09% ±4. 53% in the sham group to 29. 10% ±9. 39% in the stimulation group (t = - 4. 07, P ＜ 0. 05 ). The level of PGE2 in the stimulation group was ( 382. 30 ±20. 90) pg/ml and in the sham group was (80. 70 ± 10. 60) pg/ml (t = - 16. 674, P ＜0. 05). The number of COX-2 positive cells significantly increased from 42. 00 ± 18.40 in the sham group to 139.00 ±20. 50 in the stimulation group (t = -7. 994, P ＜0. 05). Also the COX-2 protein level was elevated from 19. 50 ±9. 20 in the sham group to 359. 20 ±21.90 in the stimulation group (t = -5. 190, P ＜0. 05). Conclusions Electrical stimulation on the unilateral trigeminal ganglion induces neurogenic inflammation in the dura mater. Changes on the neurogenic inflammation-related factors are probably the essential pathophysiological mechanism underlying the pain in migraine.

Thirty cases of cerebral hemorrhage were treated by regular therapy plus hemotherapy with ultraviolet radiation as control, with another 30 such cases treated by the same method plus injection of Radix A. Senticosi. Results showed that the marked effect of treatment group was 96. 7% and total effective rate 100%. while that of the control group were 60. 0% and 83. 3% respectively, (P