A human-airway-on-a-chip for the rapid identification of candidate antiviral therapeutics and prophylactics

The rapid repurposing of antivirals is particularly pressing during pandemics. However, rapid assays for assessing candidate drugs typically involve in vitro screens and cell lines that do not recapitulate human physiology at the tissue and organ levels. Here we show that a microfluidic bronchial-airway-on-a-chip lined by highly differentiated human bronchial-airway epithelium and pulmonary endothelium can model viral infection, strain-dependent virulence, cytokine production and the recruitment of circulating immune cells. In airway chips infected with influenza A, the co-administration of nafamostat with oseltamivir doubled the treatment-time window for oseltamivir. In chips infected with pseudotyped severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), clinically relevant doses of the antimalarial drug amodiaquine inhibited infection but clinical doses of hydroxychloroquine and other antiviral drugs that inhibit the entry of pseudotyped SARS-CoV-2 in cell lines under static conditions did not. We also show that amodiaquine showed substantial prophylactic and therapeutic activities in hamsters challenged with native SARS-CoV-2. The human airway-on-a-chip may accelerate the identification of therapeutics and prophylactics with repurposing potential.

[LncRNA ASB16-AS1 regulates the proliferation, migration and invasion of esophageal cancer cells by targeting miR-1258]

Objective: To investigate the effects of long-chain non-coding RNA ASB16 antisense RNA1 (ASB16-AS1) on the proliferation, migration and invasion of esophageal cancer cells by targeting microRNA (miR )-1258. Methods: Forty pairs of esophageal cancer tissues and matched adjacent tissues (distance of tumor margin>3 cm) resected in Xinxiang Central Hospital from May 2016 to July 2017 were collected. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expressions of ASB16-AS1 and miR-1258 in esophageal cancer tissues and adjacent tissues. The small interfering RNA negative control (si-NC), ASB16-AS1 small interfering RNA (si-ASB16-AS1), miR-negative control mimics (miR-NC), miR-1258 mimics (miR-1258), si-ASB16-AS1 and anti-miR-NC, si-ASB16-AS1 and anti-miR-1258, si-ASB16-AS1 and anti-miR-1258 were transfected into Eca109 cells, respectively. Methyl thiazolyl tetrazolium (MTT) was utilized to detect the cell viability. Transwell assays were applied to detect cell migration and invasion. Double luciferase reporting experiment and qRT-PCR were used to confirm the relationship between ASB16-AS1 and miR-1258. Results: The expression levels of ASB16-AS1 and miR-1258 in esophageal cancer tissues were 2.95±0.27 and 0.62±0.06, respectively. Compared with 1.00±0.06 and 1.00±0.07 in adjacent tissues, the difference was statistically significant (P<0.05). The cell viability of the si-NC group at 48 h and 72 h were 0.81±0.07 and 1.15±0.11, while those of si-ASB16-AS1 group were 0.46±0.04 and 0.62±0.06 (P<0.05). The numbers of cell migration and invasion in the si-NC group were 86.32±8.24 and 71.29±7.15, respectively, while those of si-ASB16-AS1 group were 43.22±4.31 and 32.36±3.58, respectively, the differences were statistically significant (P<0.05). The cell viability of the miR-NC group at 48 h and 72 h were 0.84±0.08, 1.18±0.12, while those of miR-1258 group were 0.55±0.05, 0.71±0.07 (P<0.05). The migration and invasion numbers of the miR-NC group were (83.15±8.31) and (75.33±7.51), while those of miR-1258 group were (49.58±4.23) and (38.42±3.84), respectively, the differences were statistically significant (P<0.05). The cell viability of the si-ASB16-AS1+ anti-miR-NC group at 48 h and 72 h were 0.45±0.04, 0.61±0.06, while those of si-ASB16-AS1+ anti-miR-1258 group were 0.72±0.07, 0.98±0.08; The migration and invasion numbers of cells in the si-ASB16-AS1+ anti-miR-NC group were 44.36±4.41 and 31.69±3.85, respectively, while those of si-ASB16-AS1+ anti-miR-1258 group were 72.65±7.27 and 61.22±6.14, respectively, and the differences were statistically significant (P<0.05). ASB16-AS1 targeted negative regulation of miR-1258 expression. Conclusions: ASB16-AS1 upregulates in esophageal cancer. ASB16-AS1 promotes the proliferation, migration and invasion of esophageal cancer cells by targeting miR-1258.

[Comparison of short-term and long-term efficacy between robot-assisted and thoracoscopy-laparoscopy-assisted radical esophageal cancer surgery]

Objective: To explore the safety and short-term and long-term efficacy of robot-assisted radical esophageal cancer surgery. Methods: A prospective randomized controlled trial was conducted. Patients who were preoperatively diagnosed as stage 0-IIIB esophageal squamous cell carcinoma and suitable for minimally invasive surgery in our hospital from January 1, 2014 to June 30, 2018 were prospectively enrolled. Those of age ≥75 years having received preoperative neoadjuvant therapy, contradicted to anesthesia or operation due to severe complications, with history of thoracotomy or laparotomy, with concurrent malignant tumors, without complete informations or refusing to participate in this study were excluded. Participants were randomly divided into the thoracoscopy-laparoscopy group and the robot group using a random number table in ratio of 1:1. Preoperative clinicopathological data, surgical data and postoperative outcomes were recorded. The patients were followed up mainly by telephone. Follow-up endpoint was recurrence of esophageal cancer and death. Kaplan-Meier method was used to estimate survival rate. The survival difference between the two groups was analyzed using the log-rank test. Results: According to above criteria, a total of 192 esophageal cancer patients were enrolled finally, including 144 males and 48 females with mean age of (61.9±8.6) years. The robot group had 94 cases, including 72 males and 22 females with mean age of (61.3±8.2) years, and the thoracoscopy-laparoscopy group had 98 cases, including 72 males and 26 females with mean age of (62.4±9.1) years. There were no significant differences in baseline data between the two groups (all P>0.05). Operation was abandoned in one case in each group due to extensive pleural cavity metastasis and one case in each group was converted to thoracotomy. The success rate of operation was 97.9% (92/94) in the robot group and 98.0% (96/98) in the thoracoscopy-laparoscopy group (χ(2)=0.002, P=0.996). The number of lymph nodes dissected in the robot group was significantly higher than that in the thoracoscopy-laparoscopy group (29.2±12.5 vs. 22.8±13.3, t=3.433, P=0.001), while there were no significant differences in operative time, intraoperative blood loss, R0 resection rate, postoperative 30-day mortality, postoperative hospital stay, ICU stay, time to withdrawal of chest drainage tube, ICU readmission, and postoperative morbidity of complications between the two groups (all P>0.05). The median follow-up time was 21 (3 to 57) months. During the follow-up, 3 cases and 4 cases were lost, and 2 cases and 3 cases died of other diseases in the robot group and in the thoracoscopy-laparoscopy group respectively. Recurrence occurred in 39 cases during follow-up, including 14 recurrences in the robotic group with 1- and 3-year recurrence-free survival rates of 92.4% and 87.6% respectively and the median recurrence time of 15 (9 to 42) months. There were 25 recurrences in the thoracoscopy-laparoscopy group with 1- and 3-year recurrence-free survival rates of 81.7% and 67.9% respectively and the median recurrence time of 9 (3 to 42) months. There was significant difference in recurrence-free survival between the two groups (χ(2)=4.193, P=0.041). Conclusions: The robotic surgical system has good oncology effect and surgical safety in the radical operation of esophageal cancer, which deserves further research and promotion.

[Application of tracheotomy combined with thyrocricocentesis and puncture of front tracheal wall in emergency treatment of laryngeal edema in burn patients]

Objective: To explore the effect of tracheotomy combined with thyrocricocentesis and puncture of front tracheal wall in emergency treatment of laryngeal edema in patients with burns. Methods: From November 2000 to August 2018, 22 patients with severe burn or extremely severe burn combined with acute laryngeal edema were rescued in the author's unit, including 18 males and 4 females, aged 17 to 68 years. All patients were complicated with mild inhalation injury or above and more than deep partial-thickness burn to head, face, and neck. From November 2000 to October 2012, simple emergency tracheotomy was performed for 12 cases. From May 2013 to August 2018, tracheotomy combined with thyrocricocentesis and puncture of front tracheal wall was performed for 10 cases. Rescue effect and complication of the two kinds of tracheotomy were recorded. Data were processed with Fisher's exact probability test. Results: Among the 12 patients treated with simple emergency tracheotomy, 5 cases survived and 7 cases died of suffocation during tracheotomy. Among the 10 patients treated with tracheotomy combined with thyrocricocentesis and puncture of front tracheal wall, 9 cases survived and 1 case died of cardiac arrest caused by arrhythmia. There was statistically significant difference in successful rescue effect between the two kinds of tracheotomy (P<0.05). Among the 14 patients who were successfully rescued, symptoms of insomnia and post-traumatic stress disorder occurred in 12 cases, which were relieved after symptomatic treatment for 14 to 45 d without permanent hypoxic brain damage. Conclusions: In case of loss of the condition of preventive tracheotomy, first aid of acute laryngeal edema of burn patient is very difficult. Tracheotomy combined with thyrocricocentesis and puncture of front tracheal wall is simple and rapid with high successful rate and amelioration of hypoxia, which is an ideal plan for laryngeal edema.

Lung radiodensity along the needle passage is a quantitative predictor of pneumothorax after CT-guided percutaneous core needle biopsy

AIM

To analyse whether the lowest value of lung radiodensity along the passage of the biopsy needle is a quantitative predictor of pneumothorax.

MATERIALS AND METHODS

CT-guided percutaneous core needle biopsy (PCNB) procedures performed at Zhongnan Hospital were analysed retrospectively. Age, gender, lesion size, lesion depth, lesion location, patient position, number of passages, needle pleural angle, pulmonary bleeding, and lung radiodensity along the needle passage were collected and classified by the extent of pneumothorax. Univariate analysis and multiple logistic regression analysis were assessed to explore the independent risk factors for pneumothorax.

RESULTS

Six hundred and seventy-seven cases were included in the study, including 456 males and 221 females. Pneumothorax occurred in 40.18% of cases, of which 82.4% were mild, 14% were moderate, and 3.7% were severe. Univariate and multivariate analysis showed that lesion size ≤2 cm (p=0.002), two or more passages (p=0.033), and lung radiodensity of -850 HU or less (p≤0.001) were independent risk factors for pneumothorax; bleeding (p<0.001) was a protective factor for pneumothorax.

CONCLUSIONS

The lowest value of lung radiodensity along the needle passage was a quantitative predictor of pneumothorax. A value of -850 HU or less was an independent risk factor for pneumothorax. As the value decreased, there was a higher risk of occurrence of more severe pneumothorax.

[Identification of mutations associated with coronary artery lesion susceptibility in Kawasaki disease by targeted enrichment of genomic region sequencing technique]

Objective: To screen and identify the mutations in Kawasaki disease by targeted enrichment of genomic region sequencing technique and investigate susceptibility genes associated with coronary artery lesion. Method: This was a case-control study.A total of 114 patients diagnosed as Kawasaki disease treated in Shanghai Children's Hospital between December 2015 and November 2016 were studied and another 45 healthy children who were physically examined in outpatient department were enrolled as control group. Patients were divided into two groups based on the results of echocardiogram. Peripheral venous blood was obtained from patients and controls. Genomic DNA was extracted. SeqCap EZ Choice libraries were prepared by targeted enrichment of genomic region technology. Then the libraries were sequenced to identify susceptibility genes associated with coronary artery lesion in patients diagnosed as Kawasaki disease.Susceptible genes were identified by Burden test, Pearson chi-square test or Fisher's exact probability test. Result: There was statistically significant difference in TNFRSF11B(rs2073618)G>C(p.N3K)mutation and GG/GC/CC genotype between Kawasaki disease group and control group(χ(2)=15.52, P=0.00). There was statistically significant difference in TNFRSF13B(rs34562254)C>T(p.P251L)mutation(χ(2)=10.40, P=0.01)and LEFTY1(rs360057)T>G(p.D322A)mutation(χ(2)=8.505, P=0.01)between patients with coronary artery lesions and those without. Conclusion: Targeted enrichment of genomic region sequencing technology can be used to do primary screening for the susceptible genes associated with coronary artery lesions in Chinese Kawasaki patients and may provide theoretical basis for larger sample investigation of risk prediction score standard in Kawasaki disease.

The relevance of Tim-3 polymorphisms and F protein to the outcomes of HCV infection

Hepatitis C virus (HCV) is one of the major causes of liver inflammation. The aim of this study was to investigate the associations of T-cell immunoglobulin and mucin domain-3 (Tim-3) polymorphisms and the alternate reading frame protein (F protein) with the outcomes of HCV infection. Three single-nucleotide polymorphisms (SNPs; rs10053538, rs12186731, and rs13170556) of Tim-3 were genotyped in this study, which included 203 healthy controls, 558 hepatitis C anti-F-positive patients, and 163 hepatitis C anti-F-negative patients. The results revealed that the rs12186731 CT and rs13170556 TC and CC genotypes were significantly less frequent in the anti-F-positive patients [odds ratio (OR) = 0.54, 95 % confidence interval (CI) = 0.35-0.83, p = 0.005; OR = 0.26, 95 % CI = 0.18-0.39, p < 0.001; and OR = 0.19, 95 % CI = 0.10-0.35, p < 0.001, respectively), and the rs13170556 TC genotype was more frequent in the chronic HCV (CHC) patients (OR = 1.70, 95 % CI = 1.20-2.40, p = 0.002). The combined analysis of the rs12186731 CT and rs13170556 TC/CC genotypes revealed a locus-dosage protective effect in the anti-F-positive patients (OR = 0.22, 95 % CI = 0.14-0.33, p trend < 0.001). Stratified analyses revealed that the frequencies of the rs12186731 (CT + TT) genotypes were significantly lower in the older (OR = 0.31, 95 % CI = 0.15-0.65, p = 0.002) and female (OR = 0.30, 95 % CI = 0.17-0.52, p < 0.001) subgroups, and rs13170556 (TC + CC) genotypes exhibited the same effect in all subgroups (all p < 0.001) in the anti-F antibody generations. Moreover, the rs13170556 (TC + CC) genotypes were significantly more frequent in the younger (OR = 1.86, 95 % CI = 1.18-2.94, p = 0.007) and female (OR = 2.38, 95 % CI = 1.48-3.83, p < 0.001) subgroups of CHC patients. These findings suggest that the rs12186731 CT and rs13170556 TC/CC genotypes of Tim-3 provide potential protective effects with the F protein in the outcomes of HCV infection and that these effects are related to sex and age.

TBX21 polymorphisms are associated with virus persistence in hepatitis C virus infection patients from a high-risk Chinese population

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and the varied outcomes of the infection depend on both viral and host factors. We have demonstrated that the HCV alternate reading frame protein (F protein) is related to Th1/Th2 bias which is involved in virus persistence in chronic hepatitis C (CHC) patients. The purpose of this study was to test the hypothesis that genetic variants of TBX21 (T cell specific T-box transcription factor) were associated with the outcomes of HCV infection and F protein generation. Three single nucleotide polymorphisms (SNPs) (rs17250932, rs2074190, rs4794067) in the TBX21 gene were genotyped in a case-control study in a cohort of a high-risk group, including 354 healthy controls and 747 CHC patients (190 anti-F protein antibody seronegative patients and 557 anti-F protein antibody seropositive patients). Results showed that the rs4794067 C allele in the TBX21 promoter was significantly more common in CHC patients (OR = 1.335, 95% CI = 1.058-1.684, P = 0.015), exceptionally in anti-F protein seropositive patients (OR = 1.547, 95% CI = 1.140-2.101, P = 0.005), compared with healthy controls. And the risk effect was also significantly high in patients with HCV 1b genotype and mild fibrosis (P = 0.021, P = 0.010, respectively). Compared with the most frequent haplotype TAT, haplotype analysis showed that the distribution of TAC was significantly different between the chronic HCV carrier group and the healthy group, and so was the anti-F antibody seronegativity group and the anti-F antibody seronegativity group (all P < 0.001). Our results suggested that TBX21 variants may be involved in the etiology of this disease.

Kinetics of aristolochic acid I after oral administration of Radix Aristolochiae or Guanxinsuhe preparation in canines

ETHNOPHARMACOLOGICAL RELEVANCE

Aristolochic acid I (AAI), a major component derived from Aristolochia species, which have been known for a long time and remain in use today, particularly in Asia and Central America. It has been confirmed to induce a type of so-called aristolochic acid nephropathy (AAN) and involved in the development of Balkan endemic nephropathy (BEN).

AIM OF THE STUDY

To investigate the kinetic of AAI in beagle dogs after single-dose oral administration of Radix Aristolochiae or its preparation, Guanxinsuhe, as well as the effects of compound compatibility in traditional Chinese medicine on the pathologic processes of AAN.

MATERIALS AND METHODS

Beagle dogs were orally administrated Radix Aristolochiae (0.3 g/kg/day), Guanxinsuhe preparation (0.9 g/kg/day) (with an identical dosage of AAI), and empty capsules respectively for 180 days. Canines (n=2) were euthanized on day 90, 180, 210, HPLC was established to determine the AAI level in plasma and the kinetic behaviors of AAI in dogs were elucidated after single dosing. Hematoxylin and eosin (H&E)-staining was applied for histopathologic examination to evaluate the pathological status of kidneys.

RESULTS

Compared to canines with Radix Aristolochiae treatment, the Cmax, AUC, Tmax, and t(1/2β) of AAI in Guanxinsuhe preparation group were elevated, while t(1/2α) of AAI was decreased. The results indicated the co-existing components in Guanxinsuhe preparation could increase the absorption, accelerate the distribution, but delay the absorption and elimination of AAI. After long-term dosing, animals treated with Radix Aristolochiae were found with more severe renal impairment and higher AAI level in plasma.

CONCLUSIONS

It was demonstrated that the compound compatibility in Guanxinsuhe preparation can affect the kinetic process of AAI and attenuate the toxic effect on kidney when the duration of treatment was prolonged.

Activation of liver X receptors inhibits pancreatic islet beta cell proliferation through cell cycle arrest

AIMS/HYPOTHESIS

Liver X receptors (LXRs) are important transcriptional regulators of lipid homeostasis and proliferation in several cell types. However, the roles of LXRs in pancreatic beta cells have not been fully established. The aim of this study was to investigate the effects of LXRs on pancreatic beta cell proliferation.

METHODS

Gene expression was analysed using real-time RT-PCR. Transient transfection and reporter gene assays were used to determine the transcriptional activity of LXRs in pancreatic beta cells. Cell viability and proliferation were analysed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), DNA fluorometric, BrdU labelling and [(3)H]thymidine incorporation assays. Cell cycle distribution was investigated by flow cytometry analysis. Adenovirus-based RNA interference was used to knockdown LXRalpha, LXRbeta and p27 in MIN6 cells and mouse islets.

RESULTS

We found that both Lxralpha (also known as Nr1h3) and Lxrbeta (also known as Nr1h2) were expressed and transactivated the LXR response element in HIT-T15 and MIN6 cells. Activation of LXRs dose-dependently inhibited pancreatic beta cell viability and proliferation. This was accompanied by beta cell cycle arrest at the G1 phase. Furthermore, LXR activation increased levels of the p27 protein by inhibiting its degradation. Knockdown of p27 reversed these effects of LXR activation on growth inhibition and cell cycle arrest.

CONCLUSIONS/INTERPRETATION

Our observations indicate that LXR activation inhibits pancreatic beta cell proliferation through cell cycle arrest. A well-known regulator of pancreatic beta cell cycle progression, p27, is upregulated and mediates the effects of LXRs on growth inhibition in beta cells. These observations suggest the involvement of aberrant activation of LXR in beta cell mass inadequacy, which is an important step in the development of type 2 diabetes.

Prostaglandin E2 regulates Foxo activity via the Akt pathway: implications for pancreatic islet beta cell dysfunction

AIMS/HYPOTHESIS

Prostaglandin E(2) (PGE(2)) is a well-recognised inhibitor of glucose-stimulated insulin secretion (GSIS). The aim of this study was to investigate the signalling pathway of PGE(2) in beta cell function regulation in HIT-T15 cells and isolated rat islets.

MATERIALS AND METHODS

mRNA levels of the prostaglandin E receptor 3 (Ptger3) were measured by real-time PCR. Western blot analysis was used to detect changes in the levels of PTGER3, phosphorylated and total Akt, phosphorylated and total forkhead box 'Other' (Foxo). Transient transfection and reporter assays were used to measure Foxo transcriptional activity. The biological significance of PGE(2) in beta cell function was analysed using MTT, flow cytometry and GSIS assays.

RESULTS

We found that treating HIT-T15 cells with exogenous PGE(2) stimulated Ptger3 gene expression specifically, and diminished cAMP generation. These were accompanied by the downregulation of Akt and Foxo phosphorylation in HIT-T15 cells and isolated rat islets. Moreover, PGE(2) upregulated basal and partially reversed constitutively active Akt-inactivated Foxo transcriptional activity. Furthermore, GSIS was impaired in PGE(2)-treated HIT-T15 cells and isolated islets. However, the dosage used in the above experiments did not affect beta cell viability and apoptosis. In addition, insulin-like growth factor 1 (IGF-1) pretreatment reversed the effects of PGE(2), and wortmannin treatment abolished the preventive effects of IGF-1.

CONCLUSIONS/INTERPRETATION

Our observations strongly suggest that PGE(2) can induce pancreatic beta cell dysfunction through the induction of Ptger3 gene expression and inhibition of Akt/Foxo phosphorylation without impacting beta cell viability. These results shed light on the mechanisms of PGE(2) actions in pancreatic beta cell dysfunction.

Neuronal nitric oxide synthase-derived nitric oxide inhibits neurogenesis in the adult dentate gyrus by down-regulating cyclic AMP response element binding protein phosphorylation

Neuronal nitric oxide synthase, the major nitric oxide synthase isoform in the mammalian brain, is implicated in some developmental processes, including neuronal survival, precursor proliferation and differentiation. However, reports about the role of neuronal nitric oxide synthase in neurogenesis in the adult dentate gyrus are conflicting. Here we show that 5-bromodeoxyuridine-labeled dividing progenitor cells in the dentate gyrus were significantly increased in mice receiving 7-nitroindazole, a selective neuronal nitric oxide synthase inhibitor, and in null mutant mice lacking neuronal nitric oxide synthase gene (nNOS-/-) 6 h and 4 weeks after 5-bromodeoxyuridine incorporation. The increase in 5-bromodeoxyuridine positive cells in 7-nitroindazole-treated mice was accompanied by activation of cyclic AMP response element binding protein phosphorylation in the dentate gyrus. Pretreatment with N-methyl-D-aspartate receptor antagonist MK-801 fully abolished the effects of 7-nitroindazole on neurogenesis and cyclic AMP response element binding protein phosphorylation. Furthermore, neuronal nitric oxide synthase inhibition significantly enhanced the survival of newborn cells and the number of 5-bromodeoxyuridine positive/NeuN positive cells in the dentate gyrus. These results indicate that neuronal nitric oxide synthase-derived nitric oxide suppresses neurogenesis in the adult dentate gyrus, in which N-methyl-D-aspartate receptor functions and cyclic AMP response element binding protein phosphorylation may be involved.

Inhibition of stress-activated protein kinase in the ischemic/reperfused heart: role of magnesium tanshinoate B in preventing apoptosis

The activation of stress-activated protein (SAP) kinase may lead to an induction of apoptosis that is responsible for part of the cardiomyocyte death in reperfusion injury. The objective of the present study was to investigate the mechanism by which magnesium tanshinoate B (MTB), a bioactive compound isolated from Danshen, prevents apoptosis in cardiomyocytes in the ischemic/reperfused heart. Isolated adult rat hearts were perfused by the Langendorff mode with medium containing MTB prior to the induction of normothermic global ischemia. At the end of the 30-min ischemic period, the heart was reperfused with the same medium with or without MTB for an additional 20 min. In the MTB-treated ischemic/reperfused heart, the number of apoptotic nuclei was reduced by 2.5-fold in comparison to that in untreated ischemic/reperfused controls [23 +/- 4 vs 57 +/- 7 (mean +/- SD) TUNEL-positive cells, respectively, N = 3-4, P < 0.001]. SAP kinase activity was elevated 1.7-fold in ischemic/reperfused rat hearts [35.6 +/- 3.8 vs 21.2 +/- 3.3 (control) (mean +/- SEM) relative densitometric units, N = 4-6, P < 0.05]. Treatment with MTB abolished this elevation in SAP kinase activity (25.0 +/- 5.2 relative densitometric units), which was also decreased by 40% in the nucleus. When the heart was subjected to ischemia alone, there was no significant change in SAP kinase activity in the presence or absence of MTB. MTB did not appear to affect the p38 mitogen-activated protein kinase activity in this model system. In conclusion, MTB was shown to have cardioprotective activity against apoptosis, probably through the inhibition of SAP kinase activity.

Furanochromone radical cations: generation, characterization and interaction with DNA

The radical cations of naturally occurring furanochromones visnagin (VI) and khellin (KH) have been generated and identified for the first time by use of laser flash photolysis and pulse radiolysis techniques. The lifetimes of VI(.+) and KH(.+) are determined as approximately 6 and approximately 35 micros under these conditions, respectively. Direct 308-nm excitation of VI in aqueous buffer at physiological pH results in monophotonic photoionization to generate VI(.+), with a quantum yield of 0.075, which is much higher than that of 8-methoxypsoralen and KH under identical conditions. Though VI(.+) is a more powerful oxidant than KH(.+), both of them react with guanosine mononucleotide (k=1.2x10(9) and 3.8x10(7) dm(3) mol(-1) s(-1), respectively) via electron transfer to give the guanine radical cation. Furthermore, selective oxidation of guanine in single and double strand DNA by VI(.+) was also observed. These novel findings suggest that electron transfer reactions involving furanochromone radical cations may be of considerable importance in furanochromone photochemotherapy.

Authentic identification of stigma Croci (stigma of Crocus sativus) from its adulterants by molecular genetic analysis

Stigma Croci, stigma of Crocus sativus L., is a precious traditional Chinese medicine, which is commonly used to activate blood circulation and to dissipate blood stasis. Three plant species, Carthamus tinctorius L., Hemerocallis fulva (L.) L. and Hemerocallis citrina Baroni, could carry the name Stigma Croci in the commercial markets of South East Asia. However, C. sativus is the only one that has proven its effectiveness, while the others could act as adulterants. The authentic identification of C. sativus on the market is difficult. By using molecular genetic method, the spacer domains of 5S-rRNA were cloned from the genomic DNAs that were isolated from C. sativus, C. tinctorius, H. fulva and H. citrina. The cDNAs encoding the spacer domains, about 300 to 500 bp, were sequenced. The nucleotide sequences of these four species showed great diversity, which could serve as markers for authentic identification of Stigma Croci to distinguish from its substitution and counterfeit.

Magnesium tanshinoate B (MTB) inhibits low density lipoprotein oxidation

Danshen, a Chinese herbal medicine has been widely used for the treatment of cardiovascular diseases. Magnesium tanshinoate B (MTB) is an active compound purified from Danshen. The objective of this study was to investigate the effect of MTB on the susceptibility of low density lipoproteins (LDL) to oxidative modification as well as on the accumulation of lipids in THP-1 derived macrophages. Aliquots of LDL were incubated with copper sulfate in the absence or presence of MTB. The degrees of oxidative modification of LDL were assessed by examining the relative gel electrophoretic mobility, by measuring the amount of thiobarbituric acid reactive substances (TBARS), and by continuous monitoring of the formation of conjugated dienes upon the increase in absorbency at 234 nm. MTB at concentrations of 1-10 microM significantly inhibited oxidative modification of LDL. Such inhibitory effect resulted in a decrease in the uptake of LDL by THP-1 derived macrophages. Taken together, these results clearly demonstrate that MTB inhibits oxidative modification of LDL and hence prevents the uptake of LDL by cultured macrophages. Such effect may be therapeutically relevant in protecting cells from lipid peroxidation in vascular disorders.

A novel eleven-membered-ring triterpene dilactone, pseudolarolide F and A related compound, pseudolarolide E, from Pseudolarix kaempferi

A novel eleven-membered-ring triterpene dilactone, pseudolarolide F (1), and a related compound, pseudolarolide E (2), were isolated from the seeds of Pseudolarix kaempferi, a plant indigenous to eastern China. Their structures and stereochemistry were established by spectroscopic studies, which included UV, IR, HREIMS, 2D NMR correlation methods (1H-1H COSY, 13C-H COSY, NOESY, HMQC, and HMBC), and single-crystal X-ray analysis.

Fast repairing of oxidized OH radical adducts of dAMP and dGMP by phenylpropanoid glycosides from Scrophularia ningpoensis Hemsl

AIM

To investigate the antioxidative activity of the constituents of the roots of Scrophularia ningpoensis (Chinese name: Xuanshen).

METHODS

The main compounds from the roots of Scrophularia ningpoensis were isolated and identified by chromatography and FABMS, NMR etc. Using the techniques of pulse radiolysis, the electron transfers from iridoid glycosides (IG) or phenylpropanoid glycosides (PG) to oxidized OH radical adducts of 2'-deoxyadenosine-5'-monophosphate acid (dAMP) or 2'-deoxyguanosine-5'-monophosphate acid (dGMP) were observed.

RESULTS

Two IG: harpagoside and harpagide, two PG: angoroside C and acteoside were obtained as the main hydrophilic constituents of the plant. At 0.1 mmol/L concentration, angoroside C and acteoside were able to repair the oxidized OH adducts dAMP and dGMP significantly. However, harpagoside and harpagide had no such effect. The electron transfer rate constants of angoroside C with dAMP and dGMP were 4.2 x 10(8) and 10.3 x 10(8) L.mol-1.s-1; the electron transfer rate constants of acteoside with dAMP and dGMP were 5.3 x 10(8) and 20.2 x 10(8) L.mol-1.s-1.

CONCLUSION

PG from Scrophularia ningpoensis have a potent antioxidative activity for reducing of the oxidized OH adducts of dAMP and dGMP.

Synthesis of 5-substituted analogues of huperzine A

Three 5-isosteres of huperzine A (2-4) were first synthesized. The key intermediate 10 was prepared by the reaction of acid 13 with LTA. The compounds 2 and 3 had 50% inhibition by 35 and 47 microM, respectively, which still retained antiacetylcholinesterase activity.

Phenylpropanoid glycosides from Scrophularia ningpoensis

Three phenylpropanoid glycosides named ningposides A (3-O-acetyl-2-O-feruloyl-alpha-L-rhamnopyranose), B (4-O-acetyl-2-O-feruloyl-alpha-L-rhamnopyranose) and C (3-O-acetyl-2-O-p-hydroxycinnamoyl-alpha-L-rhamnopyranose) along with the known compounds sibirioside A, cistanoside D, angoroside C, acteoside, decaffeoylacteoside and cistanoside F were obtained from the roots of Scrophularia ningpoensis.

Species identification of Radix Astragali (Huangqi) by DNA sequence of its 5S-rRNA spacer domain

About 300 species and varieties of Astragalus are identified in China, making the identification of the origin of a particular Astragalus species on the consumer market difficult. A molecular genetic approach was developed to identify various species of Astragalus. Although the 5S-rRNA coding sequence is conserved in higher eukaryotes, the spacer domain of the 5S-rRNA gene has great diversity among different species. The 5S-rRNA spacer domain was amplified by polymerase chain reaction (PCR) from the isolated genomic DNA, and the PCR products (approximately 300 bp) covering the 5S-rRNA spacer domain were sequenced. The nucleotide sequences of Astragalus membranaceus, A. membranaceus var. mongholicus, A. lehmannianus, A. hoantchy, and of one closely related species Hedysarum polybotrys (Hongqi), were determined. Diversity in DNA sequence and restriction enzyme mapping among various species was found in their 5S-rRNA spacer domains. This is the first report on the detection of 5S-rRNA spacer region sequence of Astragalus, and the results could be used for genetic identification of Huangqi.

Effect of magnesium tanshinoate B on the production of nitric oxide in endothelial cells

Nitric oxide (NO) is a potent vasodilator which plays an important role in regulating vascular tones. Danshen, a Chinese herbal medicine has been widely used for the treatment of cardiovascular diseases. The objective of this study was to investigate the effect of magnesium tanshinoate B (MTB), a compound purified from Danshen, on the production of NO in human endothelial cell line (ECV304). After cells were incubated with MTB (1-10 microM) for 1 or 4 h, amounts of NO metabolites released by cells were quantified and cellular NOS activities were determined following the conversion of [3H]arginine to [3H]citrulline. The NOS protein expression was determined by Western immunoblotting analysis. MTB (1-10 microM) stimulated the release of NO and its metabolites from endothelial cells. Following MTB treatment, the cellular NOS activities were significantly enhanced with a concomitant increase in the levels of constitutive NOS (cNOS) protein mass (110-178%). Selective activation of cNOS by MTB may be employed therapeutically in modulating NO production in endothelial cells.

Tumor necrosis factor alpha enhances the cytotoxicity induced by nitric oxide in cultured cerebral endothelial cells

It has been shown that independent sources of nitric oxide (NO) and the inflammatory cytokine tumor necrosis factor alpha (TNFalpha) contribute to the breakdown of the blood-brain barrier (BBB) in the pathogenesis of a number of brain disorders. However, the interaction of NO and TNFalpha has not been elucidated. The present study was designed to determine whether the toxicity induced by NO is altered by TNFalpha in brain capillary endothelial cells (BCECs), and if so, whether it is related to the generation of superoxide. TNFalpha (50-400 U/ml) did not produce toxicity until at a concentration of 800 U/ml. This toxic effect was completely blocked by copper-zinc superoxide dismutase (SOD)/catalase or N(omega)-nitro-L-arginine methyl ester (L-NAME) or oxyhemoglobin (HbO2). Sodium nitroprusside (SNP) reduced with 0.4 mM ascorbate (SNP/Vc) significantly increased Lactate dehydrogenase (LDH) efflux in a concentration-dependent manner. This cytotoxicity of SNP/Vc was also completely inhibited by SOD/catalase or HbO2. When SNP/Vc used in combination with 400 U/ml TNFalpha, a more remarkable LDH efflux was induced than SNP/Vc alone, even as little as 0.01 mM SNP/Vc was toxic, although a dose of 400 U/ml TNFalpha alone had no effect on LDH efflux. In addition, either 0.4 mM SNP/Vc and 800 U/ml TNFalpha alone or 0.4 mM SNP/Vc and 400 U/ml TNFalpha in combination significantly increased malondialdehyde (MDA) content, but nitric oxide synthase (NOS) activity was inhibited only by SNP/Vc and TNF in combination. These results suggest that TNFalpha enhances the toxicity of NO in BCECs and that at least part of this enhancement involves the generation of superoxide.

Phenolic glucosides and a gamma-lactone glucoside from the sprouts of Crocus sativus

Two new phenolic glucosides, a new gamma-lactone glucoside, and adenosine were isolated from the sprouts of CROCUS SATIVUS L. The new compounds were characterized as 2,4- dihydroxy-6-methoxyacetophenone-2beta-D-glucopyranoside, 2,3,4-trihydroxy-6-methoxyacetopenone-3-beta-D-glucopyranoside and 3-( S)-3-beta-D-glucopyranosyloxybutanolide, respectively. All structures were elucidated on the basis of chemical and spectroscopic evidence.

Two dichromenes from Evodia lepta

Two new dichromenes, dichromene C and dichromene D, were isolated from the aerial parts of Evodia lepta. Their structures were determined by spectroscopic analysis.

Two New Dichromenes from Evodia lepta

Two new dichromenes, 1 and 2, were isolated from the aerial parts of Evodia lepta. Their structures were determined by spectroscopic analysis.

Manuifolins D, E, and F: new isoflavonoids from Maackia tenuifolia

Chemical examination of roots of Maackia tenuifolia yielded three new isoflavans, manuifolins D, E, and F, along with the known (6aR, 12aR)-pterocarpin and (6aR,12aR)-maackiain. The new compounds were established as (3R)-5'-(1,1-dimethyl-2-propenyl)-4'- O-(3-methyl-2-butenyl)- 7,2'-dihydroxyisoflavan (1), (3R)-6,5'-bis(1,1-dimethyl-2-propenyl)-7,2',4', -trihydroxyisoflavan (2), and (3R)-5'-(1-isopropylethenyl)-8-(3-methyl-2-butenyl)-7,2',4'- trihydroxyisoflavan (3), respectively, by spectroscopic methods.

[The isolation and identification of four new 2, 2-dimethylchromenes]

Four new 2, 2-dimethylchromenes named leptol B (I), ethylleptol B (II), methylleptol B (III), leptene B (IV), along with a known chromene-methylevodionol (V) have been isolated from the aerial parts of Evodia lepta. Their structures were elucidated by spectroscopic analysis and chemical techniques.

[Actions of salvianolic acid A on CCl4-poisoned liver injury and fibrosis in rats]

AIM

To study the actions of salvianolic acid A (SA-A) on liver injury and liver fibrosis.

METHODS

The liver fibrotic rat was made by i.p. injection of CCl4. The model rats were divided into 3 groups treated with SA-A, colchicine (Col), and Salvia miltiorrhiza Bunge (SMB), respectively. Six wk later the rat liver pathology was examined, type I and III collagen in the liver were examined by immunohistochemistical method. Also hydroxyproline (Hyd) and malondialdehyde (MDA) in the liver, alanine aminotransferase (AlaAT), aspartate aminotransferase (AspAT), and albumin (Alb) levels in the serum were measured.

RESULTS

SA-A inhibited serum AlaAT and AspAT activities, decreased MDA and Hyd contents, alleviated liver fibrogenesis, protected deposition of type I and III collagen in liver matrix. The actions of SA-A on liver fibrosis were similar to those of Col and SMB, action of SA-A decreasing MDA was better than that of Col.

CONCLUSION

SA-A has marked effects against liver injury and fibrosis, associated with its anti-lipid peroxidation actions.

[Synthesis and antiarrhythmic activity of some (erythro)-phenylpropanediolamine compounds]

For the purpose of searching for new drug with high potency and simple chemical structure, the dominant conformation and structural parameters of Guan-Fu base (GFA) molecule were modelled and calculated with a SGI-4D 25G computer. The propanediolamine chain in GFA might be considered to be a pharmacophore responsible for the bioactivity and the configuration of the chain seemed important. Thus, thirteen compounds of (erythro)-p-x-PhCHOHCHOHCH2NHR(x = H, I1-7; X = NO2, II1-6) were prepared. Among them, 10 compounds showed antiarrhythmic effect on aconitine-induced arrhythmia in rats. The ED50(to stop VT) of I2 and ED50(to stop VP) of I3 were shown to be comparable with those of GFA. In the synthesis, no stereoselectivity was found in the Prevost reaction with allylamine analogues (a1-7). After a1-7 were acetylated, the erythro type products(I1-7) were obtained.

Effects of isovanihuperzine A on cholinesterase and scopolamine-induced memory impairment

AIM

To study the effects of isovanihuperzine A (IVHA) on cholinesterase and scopolamine-induced memory deficit.

METHODS

AChE and BuChE activities were determined by the colorimetric method of Ellman. The Ki value was determined by the plotting method of Lineweaver and Burk. In a behavioral test, rats were trained to perform a radial arm maze task using a partially baited procedure.

RESULTS

The anti-AChE activity of IVHA was comparable to huperzine A (Hup-A), and was more potent than those of physostigmine and galanthamine with an IC50 value of 0.11 mumol.L-1. IVHA was a mixed competitive type with a Ki value of 32 nmol.L-1. It bound to AChE in a reversible manner. IVHA at a dose of 0.2 mg.kg-1 ip significantly reversed scopolamine-induced working memory and reference memory impairments in radial arm maze.

CONCLUSION

IVHA is a new potential reversible AChE inhibitor and merits further study as a cognitive enhancer.

Grey dynamic model of predicting the long-term effects of drugs and its application to pirenzepine

In an attempt to approach the quantification of the dynamics of drug effects and the prediction of the long-term effects of drugs, a grey dynamic model was proposed and it was applied to predict the long-term effects of pirenzepine on pupils and peripheral leukocytes in dogs. The inconsiderable relative errors between the predicted and observed values suggest that the model-based equations for pupil diameter, neutrophils (%) and lymphocytes (%) which, obtained by fitting the data measured before and during initial 16 wk experiment, are acceptable for predicting the effects after 20- and 24-wk treatment with the drug.

Studies on New Components and Stereochemistry of Diterpenoids from Trypterygium wilfordii

An extensive investigation of the petroleum ether extract of TRIPTERYGIUM WILFORDII plants have revealed the presence of four new compounds, triptonoterpene, neotriptonoterpene, triptonodiol, and neotriptonolide, in addition to the diterpenes isolated and characterized earlier. The structures of these novel natural products have been elucidated.