Cytotoxic triterpenes from the acid hydrolyzate of Gynostemma pentaphyllum saponins.

One new dammarane-type triterpene, gypsapogenin A (1), was isolated from the acid hydrolyzate of total saponins from Gynostemma pentaphyllum (Thunb.) Makino, together with two known compounds, (20S,24S)-3ß,20,21ß,23ß,25-pentahydroxy-21,24-cyclodammarane (2) and (23S)-3ß-hydroxydammar-20,24-dien-21-oic acid 21,23-lactone (3). Its structural elucidations were accomplished mainly on the basis of the interpretation of spectroscopic data, such as IR, HR-TOF-MS, and NMR. The cytotoxic activities were evaluated against HepG2 and A549 human cancer cell lines.

Rhamnetin induces sensitization of hepatocellular carcinoma cells to a small molecular kinase inhibitor or chemotherapeutic agents.

BACKGROUND: The rapid development of multi-drug resistance (MDR) process has hindered the effectiveness of advanced hepatocellular carcinoma (HCC) treatments. Notch-1 pathway, which mediates the stress-response, promotes cell survival, EMT (epithelial-mesenchymal transition) process and induces anti-apoptosis in cancer cells, would be a potential target for overcoming MDR process. This study investigated the potential application of rhamnetin, a specific inhibitor of Notch-1 pathway, in anti-tumor drug sensitization of HCC treatment. METHODS: The expression of miR-34a, proteins belonging to Notch-1 signaling pathway or MDR-related proteins was detected by quantitative polymerase chain reaction (qPCR) and western blot assay. To identify whether rhamnetin induces the chemotherapeutic sensitization in HCC cells, the MTT-assays, flow cytometry, soft agar, trans-well and nude mice assays were performed. RESULTS: The endogenous expression of miR-34a was significantly increased and the expression of Notch-1 and Survivin was downregulated after rhamnetin treatment. Treatment of rhamnetin also reduced the expression of MDR related proteins P-GP (P-glycoprotein) and BCRP (breast cancer resistance protein). Rhamnetin increased the susceptibility of HCC cells and especially HepG2/ADR, a MDR HCC cell line, to a small molecular kinase inhibitor sorafenib or chemotherapeutic drugs etoposide and paclitaxel. The IC(50) value of those drugs correspondingly decreased. CONCLUSIONS: Together, our findings suggest that rhamnetin treatment may attenuate the MDR process in HCC cells. These findings may contribute to more effective strategies for HCC therapy. GENERAL SIGNIFICANCE: Rhamnetin acts as a promising sensitizer to chemotherapy and may be a novel approach to overcome the MDR process of HCC.

Antinociceptive activity of astragaloside IV in the animal model of chronic constriction injury.

To investigate the applicability of astragaloside IV (AG) for the treatment of refractory neuropathic pain, we systemically evaluated the antinociceptive activity of AG in the animal model of chronic constriction injury. We studied behaviors, electrophysiology, and biochemistry from day 2 to day 23 after the surgery. We found that when administered intraperitoneally at the dose of 60 mg/kg, AG caused significant inhibition of allodynia and hyperalgesia induced by mechanic and thermal stimuli as well as downregulation of the expressions of a series of proteins involved in mediating neuropathic pain in the dorsal root ganglia, such as P2X purinoceptor 3, glial cell-derived neurotrophic factor, glial cell-derived neurotrophic factor family receptor α1, and transient receptor potential cation channel subtypes A1 and V1. Further investigation showed that AG restored the nerve conduction velocity and the histological structure of the damaged sciatic nerve on day 23 after the surgery. Moreover, results from immunoelectron microscope showed that glial cell-derived neurotrophic factor family receptor α1 induced by AG could form a circular band in the myelin debris between the injured axons and Schwann cells, contributing toward restoration of the damaged nerve. In conclusion, in our animal model, AG effectively inhibited the neuropathic pain induced by chronic constriction injury.

Hmgcs2 regulates M2 polarization of macrophages to repair myocardial injury induced by sepsis.

The respiratory and cardiovascular systems are often the most severely impacted by the rapid onset of sepsis, which can lead to multiple organ failure. The mortality has ranged from 10 to 40% when it has evolved into septic shock. This study sought to demonstrate the potential and role of Hmgcs2 in safeguarding against cardiovascular harm in septic mouse models. The cecal ligament and puncture (CLP) model was used to induce sepsis in C57BL/6 mice, with Hmgcs2 expression in the myocardium of the mice being heightened and inflammatory factors being augmented. Subsequently, we utilized ASOs to silence the hmgcs2 gene, and found that silencing accelerated septic myocardial injury and cardiac dysfunction in CLP mice models. In contrast, hmgcs2 attenuated inflammation and apoptosis and protected against septic cardiomyopathy in murine septicemia models. Src production, spurred on by Hmgcs2, triggered the PI3K/Akt pathway and augmented M2 macrophage polarization. Moreover, the inhibition of M2 polarization by an Src antagonist significantly contributed to apoptosis of cardiomyocytes. Our research revealed that Hmgcs2 inhibited the activation of pro-inflammatory macrophages and, through Src-dependent activation of PI3K/Akt pathway, promoted the anti-inflammatory phenotype, thus safeguarding myocardial damage from sepsis. This offers a novel theoretical basis for prevention and treatment of infectious complications.

Solitary plasmacytoma of the left rib misdiagnosed as angina pectoris: A case report.

BACKGROUND: Solitary plasmacytoma in the left rib is rare and can cause chest discomfort such as chest pain and tightness, and its clinical manifestations are not typical, so it is often misdiagnosed. We report a case of left costal plasmacytoma misdiagnosed as angina pectoris. We also review the literature and provide suggestions as to how to avoid misdiagnosis. CASE SUMMARY: A 77-year-old man with a history of intermittent chest tightness for 3 years presented with pain in the left chest for 1 wk and was admitted to hospital. The cardiologists initially diagnosed angina pectoris but the findings of coronary angiography were not consistent with the symptoms. Computed tomography showed that the left eighth rib mass was accompanied by bone destruction. The patient was transferred to our department for further treatment. Preoperative biopsy indicated that the lesion was possibly malignant, and elective surgery was performed to remove the lesion. The size of the tumor was about 4 cm. The tumor was spindle-shaped and protruded into the pleural cavity, without invading the lungs. Postoperative pathology confirmed that the left rib lesion was plasmacytoma. After 14 mo follow-up, the patient died of systemic metastasis. CONCLUSION: Left rib solitary plasmacytoma is a rare disease confined to a specific rib and can cause local pain. Attention should be paid to the differential diagnosis of angina pectoris to avoid misdiagnosis.

Chitosan oligosaccharide ameliorates acute lung injury induced by blast injury through the DDAH1/ADMA pathway.

OBJECTIVE: To investigate the protective effect of chitosan oligosaccharide (COS) on acute lung injury (ALI) caused by blast injury, and explore possible molecular mechanisms. METHODS: A mouse model of blast injury-induced ALI was established using a self-made explosive device. Thirty mice were randomly assigned to control, ALI and ALI + COS groups. An eight-channel physiological monitor was used to determine the mouse physiological index. Enzyme linked immunosorbent assay was used to measure serum inflammatory factors. Hematoxylin-eosin staining, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, immunofluorescence staining, real time-polymerase chain reaction and western blot assay were used to detect inflammatory reactions, oxidative stress and apoptosis. RESULTS: Mice were sacrificed 24 hours after successful model induction. Compared with the ALI group, the heart rate, respiration and PCO2 were significantly lower, but the PO2, TCO2 and HCO3- were significantly higher in the ALI + COS group. Compared to ALI alone, COS treatment of ALI caused a significant decrease in the wet/dry lung weight ratio, indicating a reduction in lung edema, inflammatory cell infiltration, levels of tumor necrosis factor-α, interleukin (IL)-1ß, IL-4, IL-6 and nuclear factor kappa B mRNA and protein expression were reduced and IL-10 mRNA and protein expression was increased (P < 0.05). COS significantly inhibited reactive oxygen species, MDA5 and IREα mRNA and protein expressions, cell apoptosis and Bax and Caspase-3 mRNA and protein expressions, and significantly increased superoxide dismutase-1 mRNA expression, and Bcl-2 and Caspase-8 mRNA and protein expression (all P<0.05). COS significantly increased dimethylarginine dimethylaminohydrolase 1 (DDAH1) protein expression, and reduced ADMA and p38 protein expression (P< 0.05). CONCLUSION: Blast injury causes inflammation, oxidative stress and apoptosis in the lung tissues of mice. COS has protective effects on blast injury-induced ALI, possibly by promoting DDAH1 expression and inhibiting ADMA and mitogen-activated protein kinase pathways.

DDX5 promotes gastric cancer cell proliferation in vitro and in vivo through mTOR signaling pathway.

DEAD (Asp-Glu-Ala-Asp) box helicase 5 (DDX5) is an ATP-dependent RNA helicase that is overexpressed in various malignancies. Increasing evidence suggests that DDX5 participates in carcinogenesis and cancer progression via promoting cell proliferation and metastasis. However, the functional role of DDX5 in gastric cancer is largely unknown. In this study, we observed that DDX5 was significantly up-regulated in gastric cancer tissues compared with the paired adjacent normal tissues. The expression of DDX5 correlated strongly with Ki67 index and pathological stage of gastric cancer. In vitro and in vivo studies suggested that knockdown of DDX5 inhibited gastric cancer cell proliferation, colony formation and xenografts growth, whereas ectopic expression of DDX5 promoted these cellular functions. Mechanically, DDX5 induced gastric cancer cell growth by activating mTOR/S6K1. Treatment of everolimus, the specific mTOR inhibitor, significantly attenuated DDX5-mediated cell proliferation. Interestingly, the expression of DDX5 and p-mTOR in gastric cancer tissues demonstrated a positive correlation. Taken together, these results revealed a novel role of DDX5 in gastric cancer cell proliferation via the mTOR pathway. Therefore, DDX5 may serve as a therapeutic target in gastric cancer.

NaCl pretreatment attenuates H.pylori-induced DNA damage and exacerbates proliferation of gastric epithelial cells (GES-1).

BACKGROUND: Both H. pylori infection and high salt (NaCl) diet are risks of gastric cancer, however, the interaction pattern of the two is not very clear. Our objective was to investigate the effects of NaCl-pretreated H. pylori on DNA damage and proliferation of gastric epithelial cell (GES-1). METHODS: GES-1 cells were co-cultured with H.pylori or NaCl-pretreated H. pylori (with 30% NaCl) for 24 h. The morphological changes of all cells were observed by inverted phase contrast microscopy and transmission electron microscopy. Oxidative DNA damage was examined by immunofluorescence. Alterations in mitochondrial membrane potential and apoptosis rate were detected by flow cytometry and western blot, and expression of Ki-67, PCNA and P21 were evaluated using the immunocytochemical staining. RESULTS: GES-1 cells co-cultured with NaCl-pretreated H.pylori exhibited morphological changes and oxidative DNA damage. Although no significant disruption of the mitochondrial membrane potential (ΔΨm) and apoptotic rate were observed compared with control groups, there were significant decreased in Bax and Caspase3 proteins and increased in Bcl-2 protein in GES-1 cells infected with H. pylori (30) when compared with GES-1 cells cultured with H. pylori. In addition, we found a proliferative effect on GES-1 cells with an increased expression of Ki-67 and PCNA as well as a decreased p21 expression, through which the cells may acquire the potential for malignant transformation. CONCLUSION: NaCl-pretreated H. pylori possessed the ability to cause cell injury and promote proliferation in gastric epithelial cells.

Melatonin exerts protective effect on N2a cells under hypoxia conditions through Zip1/ERK pathway.

Melatonin plays a neuroprotective role in different CNS injuries. However, the molecular mechanisms underlying neuroprotection by melatonin are not well understood. Here, we studied the effects of melatonin in hypoxia-induced N2a cells and our results demonstrated that melatonin not only reduced the level of ROS and MDA, induced the increase of SOD, but also increased the cell proliferation and inhibited cell apoptosis in hypoxia-induced N2a cells. Moreover, we identified that melatonin can activate the MAPK/ERK pathway via upregulating the expression of Zip1. Therefore, this study provides a new mechanism of melatonin and need our further study in detail.

Effect of dexmedetomidine on rats with renal ischemia-reperfusion injury and the expression of tight junction protein in kidney.

To explore the protective effect of dexmedetomidine (Dex) on rats with renal ischemia-reperfusion injury and the influence of Dex on the expression of tight junction protein in kidney. Grouped 40 SPF male rats into 4 groups, sham operation group (group S), ischemia-reperfusion group (group I/R), pretreatment with Dex group (group Pre/Dex), post-treatment with Dex group (group Post/Dex), randomly, 10 rats each group. Rats in group S were anaesthetized and set up with removal of right kidney; rats in group I/R were set up with removal of right kidney and left renal artery clamping for 45 min followed by 60 min reperfusion; rats in group Pre/Dex were intravenous injected with Dex (1 µg/kg) for 30 min after indwelling catheter via femoral vein puncture; rats in group Post/Dex were intravenous injected with Dex (1 µg/kg) for 30 min after left renal reperfusion. The kidneys in each group were made out pathologic slices after 6 h I/R, stained with HE; blood samples were taken with separation plasma, creatinine (Scr) and urea nitrogen (BUN) were detected by automatic biochemical analyzer; IL-1ß and TNF-α were detected by Enzyme-linked Immunosorbent Assay (ELISA); the expression level of tight junction protein ZO-1 and protein occludin in kidney were detected by Western-blot. The results of HE staining showed that, comparing to group S, the tissue of kidney in group I/R were damaged heavily with tubules dilatation and inflammation obviously, while lightened in group Pre/Dex and group Post/Dex. The results of detection of renal function and inflammatory factors showed that, comparing to group S, Scr, BUN, IL-1ß and TNF-α were all enhanced in group I/R, group Pre/Dex and group Post/Dex, significantly (P < 0.05), while the inflammatory factors in group Pre/Dex and group Post/Dex were lower than in group I/R, significantly (P < 0.05). The results of Western-blot showed that the expression of protein ZO-1 and occludin in group Pre/Dex and group Post/Dex were higher than in group I/R, significantly (P < 0.05). Dex could reduce renal dysfunction induced by I/R, inhibit inflammatory response, up-regulate the expression of protein ZO-1 and occludin and protect renal.

Total cavopulmonary connection with extraatrial tunnel.

Between April 1997 and February 2000, total cavopulmonary connection with an extraatrial tunnel was used to treat 9 cases of complicated congenital heart disease: single ventricle (4), double-outlet right ventricle (3), mitral atresia (1), and tricuspid atresia (1). There was no mortality. One patient developed bacterial endocarditis and required reoperation after 52 days to replace the tunnel. At follow-up ranging from 11 months to 3 years, 3 patients were in New York Heart Association functional class I, and 6 were in class II. One patient with single ventricle had refractory supraventricular tachycardia after a modified Fontan operation 4 years earlier, which was cured by the total cavopulmonary connection procedure. The essential factors for a good outcome include appropriate surgical indication, avoidance of aortic crossclamping and cardiac arrest, and unobstructed anastomosis between the superior and inferior venae cavae and the pulmonary artery.