Oxalactam A, a Novel Macrolactam with Potent Anti-Rhizoctonia solani Activity from the Endophytic Fungus Penicillium oxalicum.

A novel macrolactam named oxalactam A (1), three known dipeptides (2-4) as well as other known alkaloids (5-7) were obtained from the endophytic fungus Penicillium oxalicum, which was derived from the tuber of Icacina trichantha (Icacinaceae). All chemical structures were established based on spectroscopic data, chemical methods, ECD calculations, and 13C-DP4+ analysis. Among them, oxalactam A (1) is a 16-membered polyenic macrolactam bearing a new skeleton of 2,9-dimethyl-azacyclohexadecane core and exhibited potent anti-Rhizoctonia solani activity with a MIC value of 10 µg/mL in vitro. The plausible biosynthetic pathway of 1 was also proposed via the alanyl protecting mechanism. Notably, three dipeptides (2-4) were first identified from the endophytic fungus P. oxalicum and the NMR data of cyclo(L-Trp-L-Glu) (2) was reported for the first time. In addition, the binding interactions between compound 1 and the sterol 14α-demethylase enzyme (CYP51) were studied by molecular docking and dynamics technologies, and the results revealed that the 16-membered polyenic macrolactam could be a promising CYP51 inhibitor to develop as a new anti-Rhizoctonia solani fungicide.

A New C22-Quassinoid with Anti-Pancreatic Adenocarcinoma Activity from Seeds of Brucea javanica.

An undescribed C22-quassinoid named sergeolide A (1) and fifteen known quassinoids (2-16) were obtained from the seeds of Brucea javanica (Simaroubaceae). All chemical structures were established based on spectroscopic data and X-ray diffraction analysis. Sergeolide A (1) is the first example of a naturally occurring C22-quassinoid bearing a butenolide group fused the A ring of the bruceolide skeleton from Brucea genus. And this is the first report of the NMR data for desmethyl-bruceines B (2) and C (3) and the crystal structure for bruceolide (11). In addition, all isolates were evaluated for their anti-pancreatic adenocarcinoma activity by measuring the growth inhibitory of the MIA PaCa-2 cell lines. Consequently, compounds 1, 7-10, and 12-16 exhibited potent anti-pancreatic cancer activity in vitro (IC50 =0.054∼0.357 µM).

A novel P38α MAPK activator Bruceine A exhibits potent anti-pancreatic cancer activity.

Pancreatic cancer remains one of the cancers with the poorest prognosis bearing an overall 5-year survival rate of about 5%. Efficient new chemotherapic drugs are still highly desired. Here, bruceine A, a quassinoid identified from the dried fruits of Brucea javanica (L.) Merr., displayed the most potent anti-proliferation activity against pancreatic cancer in vitro and in vivo. Phosphoproteomic analysis revealed p38α MAPK phosphorylation was involved in bruceine A's action in MIA PaCa-2 cells. Utilizing fortebio octet system and microscale thermophoresis, we found p38α MAPK had high affinity for bruceine A. Molecular docking and molecular dynamic simulations showed that bruceine A widely bound to residues (Leu171, Ala172, Met179, Thr180, Val183) in P-loop of p38α MAPK. Key determinants of bruceine A binding with P-loop of p38α MAPK were 19-C[bond, double bond]O, 22-CH3, 32-CH3, and 34-CH3. Taken together, our findings demonstrate that bruceine A binds directly to p38α MAPK, which can be used to probe the role of p38α MAPK phosphorylation in pancreatic cancer progression, and as a novel lead compound for pancreatic cancer therapy.

Evaluation of Femoral Head Perfusion by Contrast-Enhanced Ultrasound in a Rabbit Model of Steroid-Induced Osteonecrosis.

OBJECTIVES: To study the technical feasibility of contrast-enhanced ultrasound (CEUS) in evaluating femoral head perfusion in a rabbit model of steroid-induced femoral head osteonecrosis. METHODS: Twenty rabbits were divided randomly into a control group (n = 8) and an experimental group (n = 12). Rabbits in the experimental group were induced by lipopolysaccharide and methylprednisolone to build a model of steroid-induced femoral head osteonecrosis. Contrast-enhanced ultrasound examinations were performed at 3 and 5 weeks after induction. Then, pathologic examinations and microvessel density (MVD) calculations were performed on the excised rabbit femoral heads. RESULTS: The MVD of the experimental group decreased significantly 3 and 5 weeks after induction compared with that of the control group. According to the CEUS examination results, significant differences existed in the ascending slope, descending slope, mean transit time, and time to peak between the groups at 5 weeks (P < .05). A correlation analysis showed that the descending slope had a certain correlation with the MVD (correlation coefficient, 0.376). A receiver operating characteristic curve was used to analyze the capacity of the CEUS parameters to predict the occurrence of osteonecrosis. The areas under the curve for the ascending slope and descending slope were 0.758 and 0.760, respectively (P < .05). CONCLUSIONS: Contrast-enhanced ultrasound can visualize the microcirculation in steroid-induced osteonecrosis of the femoral head in rabbits and may be a useful imaging method for the early monitoring and prediction of femoral head osteonecrosis.

Polydatin attenuated food allergy via store-operated calcium channels in mast cell.

AIM: To investigate the effect of polydatin (PD), a resveratrol glucoside, on mast cell degranulation and anti-allergic activity. METHODS: After the rats were orally sensitized with ovalbumin (OVA) for 48 d and underwent PD treatment for 4 d, all the rats were stimulated by 100 mg/mL OVA for 24 h and then sacrificed for the following experiments. The small intestines from all the groups were prepared for morphology examination by hematoxylin and eosin staining. We also used a smooth muscle organ bath to evaluate the motility of the small intestines. The OVA-specific immunoglobulin E (IgE) production and interleukin-4 (IL-4) levels in serum or supernatant of intestinal mucosa homogenates were analyzed by enzyme-linked immunosorbent assay (ELISA). Using toluidine blue stain, the activation and degranulation of isolated rat peritoneal mast cells (RPMCs) were analyzed. Release of histamine from RPMCs was measured by ELISA, and regulation of PD on intracellular Ca(2+) mobilization was investigated by probing intracellular Ca(2+) with fluo-4 fluorescent dye, with the signal recorded and analyzed. RESULTS: We found that intragastric treatment with PD significantly reduced loss of mucosal barrier integrity in the small intestine. However, OVA-sensitization caused significant hyperactivity in the small intestine of allergic rats, which was attenuated by PD administration by 42% (1.26 ± 0.13 g vs OVA 2.18 ± 0.21 g, P < 0.01). PD therapy also inhibited IgE production (3.95 ± 0.53 ng/mL vs OVA 4.53 ± 0.52 ng/mL, P < 0.05) by suppressing the secretion of Th2-type cytokine, IL-4, by 34% (38.58 ± 4.41 pg/mL vs OVA 58.15 ± 6.24 pg/mL, P < 0.01). The ratio of degranulated mast cells, as indicated by vehicles (at least five) around the cells, dramatically increased in the OVA group by 5.5 fold (63.50% ± 15.51% vs phosphate-buffered saline 11.15% ± 8.26%, P < 0.001) and fell by 65% after PD treatment (21.95% ± 4.37% vs OVA 63.50% ± 15.51%, P < 0.001). PD mediated attenuation of mast cell degranulation was further confirmed by decreased histamine levels in both serum (5.98 ± 0.17 vs OVA 6.67 ± 0.12, P < 0.05) and intestinal mucosa homogenates (5.83 ± 0.91 vs OVA 7.35 ± 0.97, P < 0.05). Furthermore, we demonstrated that administration with PD significantly decreased mast cell degranulation due to reduced Ca(2+) influx through store-operated calcium channels (SOCs) (2.35 ± 0.39 vs OVA 3.51 ± 0.38, P < 0.01). CONCLUSION: Taken together, our data indicate that PD stabilizes mast cells by suppressing intracellular Ca(2+) mobilization, mainly through inhibiting Ca(2+) entry via SOCs, thus exerting a protective role against OVA-sensitized food allergy.

[Clinical significance of D-dimer activity in thrombosis of patients with return of spontaneous circulation after cardiopulmonary resuscitation].

OBJECTIVE: To investigate the clinical significance of D-dimer contents in peripheral blood for monitoring the efficacy of thrombolytic therapy in patients with return of spontaneous circulation (ROSC) of cardiopulmonary resuscitation (CPR) cardiopulmonary resuscitation after cardiac arrest. METHODS: Forty-seven patients with sudden cardiac arrest received CPR according to 2005 American Heart Association (AHA) guidelines for CPR and emergency cardiovascular care (ECC). At the early stage of ROSC, those patients underwent head and breast CT scan if they were in a state of unconsciousness and had unstable vital signs. If intracranial hemorrhage, dissection of aorta and pneumothorax were rule out, and those patients who maintained blood circulation for over 24 hours were included. The expression of D-dimer contents in peripheral blood was determined at 0, 1, 2, 4, 8, 12 h after CPR in all patients. And the patients were randomly divided into control and experiment groups. Prior to thrombolysis, the patients whose D-dimer more than 512 µg/L were classified as Group A (n = 17); those whose D-dimer below 512 µg/L Group B (n = 14); and the remaining control group whose family members refused thrombolytic therapy Group C (n = 16). The general data, Glasgow coma scale, survival rate and the change of D-dimer in peripheral blood were analyzed. RESULTS: In Group A, D-dimer level began to increase significantly at CPR 1 hour. It peaked at CPR 2 hours then decreased gradually. The final survival rate was 67%. The survival rate and GCS were higher than those of Groups B and C. In Group B, the D-dimer concentrations began to increase gradually at CPR1 hour, peaked at CPR 12 hours and then decreased. The survival rate and GCS was lower than those of Group A and similar to those of Group C. Group C was control group with no thrombolysis. CONCLUSION: For those ROSC patients with D-dimer concentrations significantly higher than usual, the pathogenesis of cardiac arrest may be concerned with thromboembolism, thrombosis in circulatory system and hyperviscosity. After an initiation of thrombolytic therapy, blocked blood vessels are recanalized, blood circulation improves and the cause of cardiac arrest is removed. Thus their survival rate becomes better. For those with D-dimer concentrations no higher than usual, the cause of cardiac arrest is not concerned with thromboembolism, thrombolytic therapy can not improve the patient outcome. And the final survival rate remains unchanged. The significance of thrombolytic therapy is none.