OBJECTIVETo determine the relationship between DNP level after human severe brain injury and hyponatremia as well as isorrhea.

METHODSThe peripheral venous plasma as control was collected from 8 volunteers. The peripheral venous plasma from 14 severe brain injury patients were collected in the 1, 3, 7 days after injury. Radioimmunoassay was used to detect the DNP concentration. Meanwhile, daily plasma and urine electrolytes, osmotic pressure as well as 24 h liquid intake and output volume were detected.

RESULTSThe normal adult human plasma DNP level was 62.46 pg/ml+/-27.56 pg/ml. In the experimental group, the plasma DNP levels were higher from day 1 to day 3 in 8 of the 14 patients than those in the control group (P(1)=0.05, P(3)=0.03). Negative fluid balance occurred in 8 patients and hyponatremia in 7 patients. The increase of plasma DNP level was significantly correlated with the development of a negative fluid balance (r =-0.69, P<0.01) and hyponatremia (chi(2) =4.38, P<0.05).

CONCLUSIONSThe increase of plasma DNP level is accompanied by the enhancement of natriuretic and diuretic responses in severe brain-injured patients, which is associated with the development of a negative fluid balance and hyponatremia after brain injury.

Adult ; Brain Injuries ; blood ; complications ; Elapid Venoms ; blood ; Female ; Humans ; Hyponatremia ; etiology ; Intracranial Hypertension ; blood ; etiology ; Male ; Middle Aged ; Peptides ; blood ; Reagent Kits, Diagnostic ; Water-Electrolyte Imbalance ; blood

OBJECTIVETo explore a new specific therapy of nasopharyngeal carcinoma (NPC) using an anti-nasopharyngeal carcinoma (NPC) monoclonal antibody BAC5 conjugate with Chinese cobra (CT) and iodine-131(131I).

METHODSBAC5 was labeled with 131I by chloramine-T method, CT was labeled with 125I using iodogen method, and BAC5 and 125I-CT were conjugated by SPDP method. The inhibitory effect of the conjugate on cultured human NPC CNE2 cells was observed using MTT assay.

RESULTSThe IC50 of 125I-CT-BAC5 conjugate was 9.17x10(-8) mol/L, and that of 131I-BAC5 was 5.83x10(8) Bq/L, and their combined administration showed obvious inhibitory effect on the NPC cells.

CONCLUSIONBoth 125I-CT-BAC5 and 131I-BAC5 have obvious inhibition effects against NPC cells, but their combined use shows stronger effects.

Animals ; Antibodies, Monoclonal ; pharmacology ; Antineoplastic Agents ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cytotoxins ; pharmacology ; Elapid Venoms ; pharmacology ; Humans ; Immunoconjugates ; pharmacology ; Iodine Radioisotopes ; pharmacology ; Nasopharyngeal Neoplasms ; pathology

OBJECTIVETo investigate the influence of najanalgesin on glutamate-glial transporter 1(GLT-1) in spinal cord of rats after L5 spinal nerve ligation and transection (SNL), and explore the spinal analgesic mechanism of najanalgesin.

METHODOne hundred male SD rats were randomly divided into 6 groups: sham(A), SNL(B), SNL + najanalgesin(C), SNL + saline (D), SNL + najanalgesin + liposome (E), SNL + najanalgesin + liposome + GLT-1 As-ODNs(F) and treated with intrathecal injections of 10 p.L saline (A and D), 40 ng X kg(-1) najanalgesin (C, E and F), qd, respectively. Besides intrathecal administration of najanalgesin the rats were intrathecally injected with 10 microL of GLT-1 antisense oligodeoxynucleotides (As-ODNs) (F) and 10 micdroL of liposome(E) once daily on day 3. The L4-L6 segments of the spinal cord were isolated in 1, 4 and 7 d(A,B,C and D), 7 d(E and F) after surgery. The mRNA and protein of GLT-1 were determined.

RESULTThe SNL model has successfully been set up. Compared to sham group, the expression of GLT-1 mRNA and protein level in group B and D both increased firstly and decreased later, the expression of GLT-1 in group C was significantly increased and kept stable, which were also higher when compared to group D in day 7th. Compared to SNL + najanalgesin group, after intrathecal injection of GLT-1 As-ODNs the GLT-1, expression of GLT-1 in F group significantly decreased. While intrathecal administration of liposome had no significant effect on the spinal GLT-1 expression.

CONCLUSIONNajanalgesin could increase the mRNA and protein expression of GLT-1 in spinal cord, which may be one of its spinal mechanisms of analgesia.

Animals ; Elapid Venoms ; pharmacology ; Elapidae ; Excitatory Amino Acid Transporter 2 ; genetics ; metabolism ; Gene Expression Regulation ; drug effects ; Male ; Neuralgia ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Spinal Cord ; drug effects ; metabolism

OBJECTIVETo study the protective effects of naja naja atra venom (NNAV) in a rat model of diabetic nephropathy (DN).

METHODSThe rat diabetes model was induced by intraperitoneal injection of streptozotocin (STZ). Thirty-two model rats were randomly divided into one DN group (n=8) and three treatment groups (n=8 each) that received NNAV at doses of 30, 90, or 270 μg/(kg·day) via oral gavage, another eight rats as normal controls. After 12 weeks, all rats were sacrificed and the changes in serum and urine biological index levels were determined by colorimetric assay. Microalbumin (mALB), N-acetyl-β- glucosaminidase (NAG) and cystatin C (CysC) concentrations were measured by ELISA. Renal tissues were sliced for pathological and immunohistochemical observations.

RESULTSComparied with the DN group, serum glucose was decreased by 31.04%, total cholesterol 21.96%, triglyceride 23.78%, serum creatinine 19.83%, blood urea nitrogen 31.28%, urinary protein excretion 45.42%, mALB 10.42%, NAG 20.65%, CysC 19.57%, whereas albumin increased by 5.55%, high-density lipoprotein-cholesterol 59.09%, creatinine clearance 19.05% in the treatment group by NNAV administration at dose of 90 μg/(kg·day). NNAV also reduced the levels of malondialdehyde in serum (22.56%) and kidney tissue (9.79%), and increased superoxide dismutase concentration in serum (15%) and decreased it in renal tissue (8.85%). In addition, under light microscopy kidney structure was improved and glomerular hypertrophy decreased by 8.29%. As shown by immunohistochemistry, NNAV inhibited transforming growth factor-β1 by 6.70% and nuclear actor-κB by 5.15%.

CONCLUSIONNNAV improves biological indexes in DN, and it may exert renoprotective effects in rats with STZ-induced diabetes.

Animals ; Body Weight ; Diabetes Mellitus, Experimental ; complications ; Diabetic Nephropathies ; drug therapy ; pathology ; Dose-Response Relationship, Drug ; Elapid Venoms ; administration & dosage ; pharmacology ; Elapidae ; physiology ; Kidney ; drug effects ; pathology ; Male ; Malondialdehyde ; Organ Size ; Rats ; Rats, Wistar ; Superoxide Dismutase

Voltage-gated K+ (Kv) channels have been considered to be a regulator of membrane potential and neuronal excitability. Recently, accumulated evidence has indicated that several Kv channel subtypes contribute to the control of cell proliferation in various types of cells and are worth noting as potential emerging molecular targets of cancer therapy. In the present study, we investigated the effects of the Kv1.1-specific blocker, dendrotoxin-kappa (DTX-kappa), on tumor formation induced by the human lung adenocarcinoma cell line A549 in a xenograft model. Kv1.1 mRNA and protein was expressed in A549 cells and the blockade of Kv1.1 by DTX-kappa, reduced tumor formation in nude mice. Furthermore, treatment with DTX-kappa significantly increased protein expression of p21Waf1/Cip1, p27Kip1, and p15INK4B and significantly decreased protein expression of cyclin D3 in tumor tissues compared to the control. These results suggest that DTX-kappa has anti-tumor effects in A549 cells through the pathway governing G1-S transition.
Adenocarcinoma/drug therapy/genetics/pathology ; Animals ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Disease Models, Animal ; Elapid Venoms/*pharmacology ; Elapidae ; Humans ; Kv1.1 Potassium Channel/*antagonists & inhibitors/deficiency/genetics/metabolism ; Lung Neoplasms/*drug therapy/genetics/pathology ; Mice ; Mice, Nude ; Neoplasm Transplantation ; Potassium Channel Blockers/*pharmacology ; RNA, Messenger/genetics ; Transplantation, Heterologous

Dendroaspis natriuretic peptide (DNP), a new member of the natriuretic peptide family, is structurally similar to atrial, brain, and C-type natriuretic peptides. However, the effects of DNP on the cardiac function are poorly defined. In the present study, we examined the effect of DNP on the cardiac L-type Ca2+ channels in rabbit ventricular myocytes. DNP inhibited the L-type Ca2+ current (ICa,L) in a concentration dependent manner with a IC50 of 25.5 nM, which was blocked by an inhibitor of protein kinase G (PKG), KT5823 (1 microM). DNP did not affect the voltage dependence of activation and inactivation of ICa,L. The alpha1c subunit of cardiac L-type Ca2+ channel proteins was phosphorylated by the treatment of DNP (1 microM), which was completely blocked by KT5823 (1 microM). Finally, DNP also caused the shortening of action potential duration in rabbit ventricular tissue by 22.3 +/- 4.2% of the control (n = 6), which was completely blocked by KT5823 (1 microM). These results clearly indicate that DNP inhibits the L-type Ca2+ channel activity by phosphorylating the Ca2+ channel protein via PKG activation.
Action Potentials/drug effects ; Animals ; Biological Transport/drug effects ; Calcium/metabolism ; Calcium Channels, L-Type/*metabolism ; Carbazoles/pharmacology ; Cells, Cultured ; Cyclic GMP-Dependent Protein Kinases/antagonists & inhibitors ; Elapid Venoms/*metabolism/pharmacology ; Enzyme Activation ; Heart ; Heart Ventricles/drug effects ; Myocytes, Cardiac/drug effects ; Patch-Clamp Techniques ; Peptides/*metabolism/pharmacology ; Phosphorylation/drug effects ; Rabbits

BACKGROUNDNajanalgesin, a toxin isolated from the venom of Naja naja atra, has been shown to exert significant analgesic effects in a neuropathic pain model in rats. However, the molecular mechanism underlying this protective effect of najanalgesin is poorly understood. The present study sought to evaluate the intracellular signaling pathways that are involved in the antinociceptive effect of najanalgesin on neuropathic pain.

METHODSThe antinociceptive properties of najanalgesin were tested in hind paw withdrawal thresholds in response to mechanical stimulation. We analyzed the participation of the mitogen-activated protein kinase p38, extracellular-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) by western blot analysis. This inhibition of JNK was confirmed by immunohistochemistry.

RESULTSThe phosphorylation levels of JNK (as well as its downstream molecule c-Jun), p38, and ERK were significantly increased after injury. Najanalgesin only inhibited JNK and c-Jun phosphorylation but had no effect on either ERK or p38. This inhibition of JNK was confirmed by immunohistochemistry, which suggested that the antinociceptive effect of najanalgesin on spinal nerve ligation-induced neuropathic pain in rats is associated with JNK activation in the spinal cord.

CONCLUSIONThe antinociceptive effect of najanalgesin functions by inhibiting the JNK in a neuropathic pain model.

Animals ; Elapid Venoms ; therapeutic use ; Extracellular Signal-Regulated MAP Kinases ; genetics ; metabolism ; Immunohistochemistry ; JNK Mitogen-Activated Protein Kinases ; genetics ; metabolism ; Male ; Neuralgia ; drug therapy ; enzymology ; Proto-Oncogene Proteins c-jun ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; p38 Mitogen-Activated Protein Kinases ; genetics ; metabolism

Among the enzymes found in snake venom, ribonuclease (RNase) has been known to have the potential effect against cancer and HIV. In a previous report, the author and his colleague have demonstrated that RNase from Vietnamese black cobra (Naja naja) venom differed from all the other identified RNase for its extremely low optimal value of pH. The results in this study showed that it also differed in nonlinear activity dependence on the enzyme concentrations and a sigmoidal curve of saturation with the substrate. This enzyme expressed the maximal activity at the ionic strength of 10 mM of the reaction buffers. Ammonium sulfate entirely suppressed the enzyme activity at the concentration over 70 mM, and sodium chloride reduced the activity by 70% at the level over 100 mM. No magnesium ion was needed for the activation of this RNase.
Snake Venoms ; Snakes ; Animals, Poisonous ; Black Cobra Venom

BACKGROUND AND OBJECTIVES: Hyperacute rejection (HAR) is a major obstacle to successful xenotransplantation of vascularized organs. This study was conducted to observe the effect of hemolysis of perfused human whole blood on pig heart function, and determine the major risk factors for preservation of xenoperfused cardiac function using ex-vivo pig to human xenogeneic cardiac perfusion model. MATERIALS AND METHODS: Harvested pig hearts were perfused with normal human whole blood (group 1), two different types of pre-treated human whole blood (group 2: immunoglobulins were depleted by plasmapheresis, group 3: pre-treated with plasmapheresis, GAS914, cobra venom factor (CVF) and steroid), and normal porcine whole blood as control (group 4) for 3 hours. RESULTS: Duration of heart beat was significantly prolonged in group 2 and group 3. Histological examination showed widespread HAR features but was gradually delayed in groups 2 and 3 compared to group 1. The absolute levels of serum creatine kinase-MB and Troponin I increased gradually, and was lower in group 3. Serum hemoglobin levels were rapidly increased in groups 3 and 4, compared to group 1. Extracellular potassium level increased sharply from the beginning of blood perfusion in groups 1, 2 and 3, compared to group 4. CONCLUSION: Pretreatment of human whole blood, including immunoglobulin depletion, CVF and steroid reduced and delayed the destruction of pig myocardium by HAR. However, the increased extracellular potassium levels in groups 1, 2 and 3 reflected that these treatments could not prohibit myocardial injury by HAR.
Cobra Venoms ; Creatine ; Diphtheria Toxoid ; Extracorporeal Circulation ; Haemophilus Vaccines ; Heart ; Hemoglobins ; Hemolysis ; Humans ; Hyperkalemia ; Immunoglobulins ; Myocardium ; Perfusion ; Plasmapheresis ; Potassium ; Rejection (Psychology) ; Risk Factors ; Transplantation, Heterologous ; Trisaccharides ; Troponin I

PURPOSE: Breast cancer is a significant health problem worldwide, accounting for a quarter of all cancer diagnoses in women. Current strategies for breast cancer treatment are not fully effective, and there is substantial interest in the identification of novel anticancer agents especially from natural products including toxins. Cytotoxins are polypeptides found in the venom of cobras and have various physiological effects. In the present study, the anticancer potential of cytotoxin-II against the human breast adenocarcinoma cell line (MCF-7) was investigated. METHODS: The cytotoxic effects of cytotoxin-II were determined by morphological analysis and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The mode and mechanism of cell death were investigated via acridine orange/ethidium bromide (AO/EtBr) double staining, flow cytometric analysis of cell death, detection of mitochondrial membrane potential, measurement of intracellular reactive oxygen species (ROS), annexin V/propidium iodide staining, and caspase-9 activity assays. RESULTS: The half maximal inhibitory concentration (IC50) of cytotoxin-II in MCF-7 cells was 4.18+/-1.23 microg/mL, while the value for cisplatin was approximately 28.02+/-1.87 microg/mL. Morphological analysis and AO/EtBr double staining showed typical manifestations of apoptotic cell death (in doses lower than 8 microg/mL). Dose- and time-dependent ROS generation, loss of mitochondrial membrane potential, caspase-9 activation, and cell cycle arrest were observed in their respective tests. CONCLUSION: In conclusion, cytotoxin-II has potent anticancer effects in the MCF-7 cell line, which are induced via the intrinsic pathways of apoptosis. Based on these findings, cytotoxin-II is a suitable choice for breast cancer treatment.
Adenocarcinoma* ; Antineoplastic Agents ; Apoptosis* ; Biological Products ; Breast Neoplasms ; Breast* ; Caspase 9 ; Cell Cycle Checkpoints ; Cell Death ; Cell Line* ; Cisplatin ; Cobra Venoms* ; Cytotoxins ; Diagnosis ; Elapidae ; Female ; Humans ; MCF-7 Cells ; Membrane Potential, Mitochondrial ; Peptides ; Reactive Oxygen Species ; Snakes ; Venoms