Asian Pacific Journal of Tropical Medicine

525-534

Authors: Sudaratana R. Krungkrai, Jerapan Krungkrai

Malaria is a major cause of morbidity and mortality in humans. Artemisinins remain as the first-line treatment for Plasmodium falciparum (P. falciparum) malaria although drug resistance has already emerged and spread in Southeast Asia. Thus, to fight this disease, there is an urgent need to develop new antimalarial drugs for malaria chemotherapy. Unlike human host cells, P. falciparum cannot salvage preformed pyrimidine bases or nucleosides from the extracellular environment and relies solely on nucleotides synthesized through the de novo biosynthetic pathway. This review presents significant progress on understanding the de novo pyrimidine pathway and the functional enzymes in the human parasite P. falciparum. Current knowledge in genomics and metabolomics are described, particularly focusing on the parasite purine and pyrimidine nucleotide metabolism. These include gene annotation, characterization and molecular mechanism of the enzymes that are different from the human host pathway. Recent elucidation of the three-dimensional crystal structures and the catalytic reactions of three enzymes: dihydroorotate dehydrogenase, orotate phosphoribosyltransferase, and orotidine 5′-monophosphate decarboxylase, as well as their inhibitors are reviewed in the context of their therapeutic potential against malaria.

542-546

Authors: Ryong Kong, Ok-Hwa Kang, Yun-Soo Seo, Su-Hyun Mun, Tian Zhou, Dong-Won Shin, Dong-Yeul Kwon

Objective To investigate the gene related to β-lactam resistance and to confirm the mechanism about a synergy effect between CPZ and β-lactam antibiotics. Methods To measure antibacterial activity, we performed a minimum inhibitory concentration (MIC) and synergy test. Transmission electron microscopy (TEM) was used in morphological analysis. To analyze gene expression, we conducted reverse transcriptase polymerase chain reaction (PCR). Results We confirmed a synergy effect between CPZ and β-lactam antibiotics. Furthermore, we observed that CPZ affect the cell envelope of MRSA by using TEM. At the gene level, CPZ reduced the expression of resistance genes. Conclusions Through this result, we hypothesize that a decrease of resistance factor expressions was caused by CPZ because it disrupts the activity of a sensor protein located in the cell membrane.

554-561

Authors: Hanène Zater, Joëlle Huet, Véronique Fontaine, Samir Benayache, Caroline Stévigny, Pierre Duez, Fadila Benayache

Objective To investigate the chemical composition of a moderately polar extract (CHCl3 soluble part of the MeOH–H2O extract) obtained from the aerial parts (leaves and flowers) of Centaurea diluta Ait. subsp. algeriensis (Coss. & Dur.) Maire, a species endemic to Algeria and Morocco on which no reports are available to date. To evaluate in vitro the cytotoxic, antifungal and antimicrobial activities of this extract and the cytotoxic and antimicrobial activities of its isolated secondary metabolites. Methods The cytotoxic effects of the extract were investigated on 3 human cancer cell lines i.e. the A549 non-small-cell lung carcinoma (NSCLC), the MCF7 breast adenocarcinoma and the U373 glioblastoma using a MTT colorimetric assay. Biological data allowed to guide the fractionation of the extract by separation and purification on silica gel 60 (CC and TLC). The isolated compounds which were characterized by spectral analysis, mainly HR-ESIMS, HR-EIMS, UV and NMR experiments (1H, 13C, COSY, ROESY, HSQC and HMBC) and comparison of their spectroscopic data with those reported in the literature, were evaluated for cytotoxic activities on six cancer cell lines (A549, MCF7, U373, Hs683 human glioma, PC3 human prostate and B16-F10 murine melanoma). The direct and indirect antibacterial and antifungal activities were determined using microdilution methods for the raw extract and TLC-bioautography and microdilution methods against standard and clinical strains for the isolated compounds. Results The raw extract reduced cell viability with IC50s of 27, 25 and 21 μg/mL on A549, MCF7 and U373, respectively. Five secondary metabolites: two phenolic compounds (vanillin 1, paridol 3), a lignan [(−)-arctigenin 2] and two flavonoid aglycones (eupatilin 4 and jaceosidin 5), were then isolated from this extract. Moderate cytotoxic effects were observed for (−)-arctigenin 2 (IC50s: 28 and 33 μM on Hs683 and B16-F10, respectively), eupatilin 4 (IC50s: 33 and 47 μM on B16-F10 and PC3, respectively) and jaceosidin 5 (IC50s: 32 and 40 μM on PC3 and B16-F10, respectively). Conclusions All the isolated compounds were described for the first time from this species. Although inactive against 7 tested microorganisms (fungi, bacteria and yeast, human or plant pathogens), the raw extract was able to potentiate the effect of beta-lactam antibiotics on methicillin-resistant Staphylococcus aureus (MRSA), reducing the minimal inhibitory concentrations (MICs) by a factor of 2-32-fold. No synergy was found between the extract and streptomycin. From the five isolated compounds only jaseosidin 5 showed a moderate antimicrobial activity.

567-571

Authors: Qiang Wu, Gang Wu, Jing-Xiang Li

Objective To study the effect of hypoxia on the expression of placental trophoblast cells SATB1 and β-catenin and its correlation with the pathogenesis of preeclampsia. Methods Trophoblastic cell lines HRT8/SVneo were cultured, SATB1 and β-catenin expression and cell biological behavior were determined after hypoxia reoxygenation treatment; cell biological behavior and the expression of related genes were determined after the transfection of SATB1 and β-catenin siRNA; preeclampsia placenta and normal placenta tissues were collected and the expression of SATB1 and β-catenin were determined. Results OD value, cell migration rate, mRNA contents of SATB1 and β-catenin of H/R group were significantly lower than those of Nor group, cell apoptosis rate was higher than that of Nor group and the number of invasive cells was less than that of Nor group; OD value and bcl-2 mRNA content of SATB1-siRNA group were lower than those of NC group; cell apoptosis rate as well as Bax, Caspase-3, Caspase-6 and Caspase-9 mRNA contents were higher than those of NC group; cell migration rate as well as CTSB, CTSD, MMP2 and MMP9 mRNA contents of β-catenin-siRNA group were lower than those of NC group; the number of invasive cells was less than that of NC group; the expression levels of SATB1 and β-catenin in preeclampsia placenta tissue were significantly lower than those in normal placenta tissue. Conclusions Hypoxia can inhibit the expression of SATB1 and β-catenin in the pathogenesis of preeclampsia, which can affect the proliferation, apoptosis, migration and invasion of cells.

577-581

Authors: Yi Zhang, Wei Yan, Pu-Feng Ge, Yan Li, Qian Ye

Objective To observe preventive and therapeutic effects and the mechanism of actions on Zishen Yutai pill combined with progesterone on threatened abortion in rats. Methods After pregnancy, 50 SPF female SD rats were selected and divided into control group, model group, progesterone group, Zishen Yutai pill group, and progesterone plus Zishen Yutai pill group (combination group), with 10 rats in each group. The rats of control group and abortion model group were lavaged with 2 mL/kg normal saline on pregnancy day 1 for continuous 10 days. Rats in Zishen Yutai pill group were given 1.575 g/kg/d of Zishen Yutai pill for intragastric administration for continuous 10 days. Rats in progesterone group were given intramuscular injection treatment of 0.1 mL/d progestin, continuous for 10 days. Rats in combination group were given injection therapy of aqueous solution of Zishen Yutai pill for continuous 10 days, and other treatments were the same as previous two groups. Abortion model were established then and live births, numbers of abortion and average rate of abortion were compared between the five groups. Peripheral blood was collected to detect the estradiol (E2) and progestational hormone (P), and obtain ratio of Th1/Th2 cytokines (IL-2, INF-γ, IL-4, IL-10). Results Significant more live births of rats were found in the control group compared with other four groups (P < 0.05) (P < 0.05). The numbers of live births of the rats in abortion model group were significantly less than that of progesterone group, Zishen Yutai pill group and joint group (P < 0.05). The numbers of live births of rats in joint group were significant more than that of progesterone group and Zishen Yutai pill group. The serum E2 level of P of rats in the control group, progesterone group, Zishen Yutai pill group and joint group were significant higher than that of abortion model group (P < 0.05). Serum levels of E2 and P of rats in the control group, progesterone group, Zishen Yutai pill group and joint group were not significant different (P > 0.05) but these levels in the control group and Zishen Yutai pill group were significant lower than that of progesterone group and joint group (P < 0.05). The maternal–fetal interface IL – 4/IL – 2, IL – 10/IL – 2 of model group were balanced deviating to Th1, while the IL-4/IL-2, IL-10/IL-2 of progesterone group, Zishen Yutai pill group and joint group were balanced deviating to Th2, and joint group’ deviation was better than progesterone group and Zishen Yutai pill group (P < 0.05). Conclusions Zishen Yutai pill combined with progesterone has a significant control effect for threatened abortion, which can obviously increase contents of maternal serums E2 and P, and regulate the Th1/Th2 balance with a remarkable effect.

587-591

Authors: Yu-Zhi Liang, Zhi-Lei Zeng, Lin-Lin Hua, Jin-Feng Li, Yun-Liang Wang, Xi-Zhuang Bi

Objective To discuss the expression and significance of angiostatin, vascular endothelial growth factor and matrix metalloproteinase-9 in the brain tissue of diabetic rats with ischemia reperfusion. Methods A total of 60 male Wistar rats were randomly divided into the normal group, sham group, diabetic cerebral infarction group and single cerebral infarction group according to the random number table, with 15 rats in each group. The high sucrose diet and intraperitoneal injection of streptozotocin were performed for the modeling of diabetic rats, while the thread-occlusion method was employed to build the model of cerebral ischemia reperfusion. The immunohistochemical staining was performed to detect the expression of angiostatin, vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) in the brain tissue. Results The expression of angiostatin after the reperfusion in the brain tissue of rats in the single cerebral infarction group and diabetic cerebral infarction group was increased 6 h after the reperfusion, reached to the peak on 1 d and then decreased gradually. The expression of angiostatin in the diabetic cerebral infarction group 6 h, 1 d, 3 d and 7 d after the reperfusion was significantly higher than that in the single cerebral infarction group (P < 0.05). VEGF began to be increased 1 h after the reperfusion in the single cerebral infarction group and diabetic cerebral infarction group, reached to the peak at 6 h and then decreased gradually. The expression of VEGF in the diabetic cerebral infarction group at each time point after the reperfusion was significantly lower than that in the single cerebral infarction group (P < 0.05). MMP-9 began to be increased 1 h after the reperfusion in the single cerebral infarction group and diabetic cerebral infarction group, reached to the peak on 1 d and then decreased gradually. The expression of MMP-9 in the diabetic cerebral infarction group at each time point after the reperfusion was significantly higher than that in the single cerebral infarction group (P < 0.05). Conclusions The high glucose environment in which the diabetic cerebral infarction is occurred is to induce the formation of MMP-9 at first and then activate and increase the expression of angiostatin. Afterwards, the expression of VEGF is inhibited, resulting in the poor angiogenesis after cerebral infarction, which thus makes the injury of brain tissue after cerebral infarction even worse than the non-diabetes mellitus.

597-600

Authors: Wei Zhou, Ming-Yu Fan, You-Xiu Wei, Song Huang, Jing-You Chen, Ping Liu

Objective To determine the expression of non-muscle myosin heavy chain 9 (MYH9) in osteosarcoma and its effect on the migration and invasion abilities of tumor cell. Methods A total of 65 cases of osteosarcoma and 20 cases with benign osteochondroma who underwent resection operation in the Orthopaedics Department of our hospital from January 1st 2009 to January 1st 2015 were selected. Their mRNA levels of MYH9 were tested by qrt-PCR. Immunohistochemical method was used to examine the expression of MYH9 in osteosarcoma and the correlation between the positive expression of MYH9 and the clinicopathological features of patients was illustrated by statistical analysis. MYH9 was compounded artificially. The expression of MYH9 in SAOS2 osteosarcoma cells was decreased by siRNA. Scratch test was used to determine the change of SAOS2 cell migration ability after MYH9 silence. Transwell assay was employed to detect the change of cell invasion ability after MYH9 silence. Results The expression levels of mRNA of MYH9 and protein in osteosarcoma tissues were significantly higher than those in benign osteochondroma tissues. The high expression of MYH9 in osteosarcoma tissues was apparently related to the high Enneking classification (III classification) and lung metastasis. SiRNA of MYH9 could evidently decrease the expression level of MYH9 in SAOS2. The down-regulated expression of MYH9 could inhibit the migration and invasion abilities of SAOS2 cells. Conclusions MYH9 shows a trend of high expression in osteosarcoma tissues, and its high expression is associated with features such as tumor invasion and metastasis. The down-regulated MYH9 can realize an anti-tumor effect by inhibiting the migration and invasion of osteosarcoma cells.

606-609

Authors: Gui-Feng Zhuang, Yan Tan, Yuan-Zheng Yang, Jie-Wei Zhang, Jing Tang

Objective To study the influence of cisplatin implants on transplantation tumor growth and the expression of tissue kallikrein-7 (KLK7) and E-cadherin (E-cad) in tumor-bearing mice with gastric cancer. Methods BALB/c nude mice were collected as experimental animal and were randomly divided into model control group (Group A), tail intravenous injection of cisplatin group (Group B), intratumor injection of cisplatin group (Group C) and cisplatin implants treatment group (Group D). After the drugs intervening, the weight and volume of transplantation tumors were measured on Day 20, Day 30 and Day 40 and serum and KLK7 and E-cad contents in transplanted tumor tissue were examined. Results On Day 20, Day 30 and Day 40 after treatment, the weight and volume of transplantation tumors of tumor-bearing mice in four groups were different (Group A > Group B > Group C > Group D). The contents of KLK-7 and E-cad in tumor tissue and serum of tumor-bearing mice in four groups were different (Group A > Group B > Group C > Group D in KLK-7) and (Group A < Group B < Group C < Group D in E-cad). The weight and volume, and KLK7 and E-cad contents of transplantation tumors in four groups were significant difference (P < 0.05). Conclusion Cisplatin implants can inhibit the growth of transplanted tumor tissue and down-regulated KLK7 expression and up-regulated E-cad expression of tumor-bearing mice with gastric cancer.

614-615

Authors: Somsri Wiwanitkit, Viroj Wiwanitkit

None

619-620

Authors: Maria Teresa Galán-Puchades

None