Caudal Vein Injection Research Articles

Early stage transplantation of bone marrow cells markedly ameliorates copper metabolism and restores liver function in a mouse model of Wilson disease

BackgroundRecent studies have demonstrated that normal bone marrow (BM) cells transplantation can correct liver injury in a mouse model of Wilson disease (WD). However, it still remains unknown when BM cells transplantation should be administered. The aim of this study was to investigate the potential impact of normal BM cells transplantation at different stages of WD to correct liver injury in toxic milk (tx) mice.MethodsRecipient tx mice were sublethally irradiated (5 Gy) prior to transplantation. The congenic wild-type (DL) BM cells labeled with CM-DiI were transplanted via caudal vein injection into tx mice at the early (2 months of age) or late stage (5 months of age) of WD. The same volume of saline or tx BM cells were injected as controls. The DL donor cell population, copper concentration, serum ceruloplasmin oxidase activity and aspartate aminotransferase (AST) levels in the various groups were evaluated at 1, 4, 8 and 12 weeks post-transplant, respectively.ResultsThe DL BM cells population was observed from 1 to 12 weeks and peaked by the 4th week in the recipient liver after transplantation. DL BM cells transplantation during the early stage significantly corrected copper accumulation, AST across the observed time points and serum ceruloplasmin oxidase activity through 8 to 12 weeks in tx mice compared with those treated with saline or tx BM cells (all P < 0.05). In contrast, BM cells transplantation during the late stage only corrected AST levels from 4 to 12 weeks post-transplant and copper accumulation at 12 weeks post-transplant (all P < 0.05). No significant difference was found between the saline and tx BM cells transplantation groups across the observed time points (P > 0.05).ConclusionsEarly stage transplantation of normal BM cells is better than late stage transplantation in correcting liver function and copper metabolism in a mouse model of WD.

Molecular Characterization of the NPC1L1 Variants Identified from Cholesterol Low Absorbers

Niemann-Pick C1-like 1 (NPC1L1) is an essential protein for dietary cholesterol absorption. Nonsynonymous (NS) variants of NPC1L1 in humans have been suggested to associate with cholesterol absorption variations. However, information concerning the characteristics and mechanism of these variants in cholesterol uptake is limited. In this study, we analyzed the cholesterol uptake ability of the 19 reported NS variants of NPC1L1 identified from cholesterol low absorbers. Among these variants, L110F, R306C, A395V, G402S, T413M, R693C, R1214H, and R1268H could partially mediate cellular cholesterol uptake and were categorized as partially dysfunctional variants. The other 11 variants including T61M, N132S, D398G, R417W, G434R, T499M, S620C, I647N, G672R, S881L, and R1108W could barely facilitate cholesterol uptake, and were classified into the severely dysfunctional group. The partially dysfunctional variants showed mild defects in one or multiple aspects of cholesterol-regulated recycling, subcellular localization, glycosylation, and protein stability. The severely dysfunctional ones displayed remarkable defects in all these aspects and were rapidly degraded through the ER-associated degradation (ERAD) pathway. In vivo analyses using adenovirus-mediated expression in mouse liver confirmed that the S881L variant failed to localize to liver canalicular membrane, and the mice showed defects in biliary cholesterol re-absorption, while the G402S variant appeared to be similar to wild-type NPC1L1 in mouse liver. This study suggests that the dysfunction of the 19 variants on cholesterol absorption is due to the impairment of recycling, subcellular localization, glycosylation, or stability of NPC1L1.

A High-Throughput Screen for Tuberculosis Progression

One-third of the world population is infected with Mycobacterium tuberculosis and multi-drug resistant strains are rapidly evolving. The noticeable absence of a whole organism high-throughput screening system for studying the progression of tuberculosis is fast becoming the bottleneck in tuberculosis research. We successfully developed such a system using the zebrafish Mycobacterium marinum infection model, which is a well-characterized model for tuberculosis progression with biomedical significance, mimicking hallmarks of human tuberculosis pathology. Importantly, we demonstrate the suitability of our system to directly study M. tuberculosis, showing for the first time that the human pathogen can propagate in this vertebrate model, resulting in similar early disease symptoms to those observed upon M. marinum infection. Our system is capable of screening for disease progression via robotic yolk injection of early embryos and visual flow screening of late-stage larvae. We also show that this system can reliably recapitulate the standard caudal vein injection method with a throughput level of 2,000 embryos per hour. We additionally demonstrate the possibility of studying signal transduction leading to disease progression using reverse genetics at high-throughput levels. Importantly, we use reference compounds to validate our system in the testing of molecules that prevent tuberculosis progression, making it highly suited for investigating novel anti-tuberculosis compounds in vivo.

Therapeutic effects and mechanisms of bone marrow derived mesenchymal stem cells in treating chronic pancreatitis of rats

Objective observe the therapeutic effects and to investigate the mechanisms of bone marrow derived mesenchymal stem cells(BMSCs) in treating chronic pancreatitis of rats. Methods BMSCs were isolated, cultured and amplified. Then, BMSCs were transfected with enhanced green fluorescent proteins combined with Ad5/F35 adenovirus vector. Chronic pancreatitis(CP) rat model was induced by infusion of oleic acid to bil-iopancreatic duct. Then, EGFP-BMSCs were transplanted to the CP rats through caudal vein injection for 3 times. Pancreatic tissues were collected and histopathological changes were observed under light microscope. Pancreatic CTGF,TGF-β,type-Ⅰ collagen, type-Ⅲ collagen and myeloperoxidase (MPO)activity were detected. The percentage of EGFP-labeled cells in the pancreatic tissue was examined by flow cytometer. Results The pathological injury and the fibrosis of BMSCs treated group were ameliorated significantly compared to those of CP group. The contents of pancreatic CTGF, TGF-β, type-Ⅰ collagen, type-Ⅲ collagen and MPO were all decreased obviously. The percentage of EGFP-labeled cells in the pancreatic tissue of BMSCs treated group was much higher than that of the negative control group. Conclusions BMSCs have obvious therapeutic effects in the treatment of CP, which may be related to their recruitments to the damaged pancreatic tissue as seed cells and their inhibition of CTGF,TGF-P release by autocrine or paracrine effects, thus decreasing the type-Ⅰ collagen, type-Ⅲ collagen and MPO producing. Key words: Bone marrow derived mesenchymal stem cells; Chronic pancreatitis; Fibrosis; Green fluorescent proteins; Flow cytometer

P110 CUX1 Homeodomain Protein Stimulates Cell Migration and Invasion in Part through a Regulatory Cascade Culminating in the Repression of E-cadherin and Occludin

In this study, we investigated the mechanism by which the CUX1 transcription factor can stimulate cell migration and invasion. The full-length p200 CUX1 had a weaker effect than the proteolytically processed p110 isoform; moreover, treatments that affect processing similarly impacted cell migration. We conclude that the stimulatory effect of p200 CUX1 is mediated in part, if not entirely, through the generation of p110 CUX1. We established a list of putative transcriptional targets with functions related to cell motility, and we then identified those targets whose expression was directly regulated by CUX1 in a cell line whose migratory potential was strongly stimulated by CUX1. We identified 18 genes whose expression was directly modulated by p110 CUX1, and its binding to all target promoters was validated in independent chromatin immunoprecipitation assays. These genes code for regulators of Rho-GTPases, cell-cell and cell-matrix adhesion proteins, cytoskeleton-associated proteins, and markers of epithelial-to-mesenchymal transition. Interestingly, p110 CUX1 activated the expression of genes that promote cell motility and at the same time repressed genes that inhibit this process. Therefore, the role of p110 CUX1 in cell motility involves its functions in both activation and repression of transcription. This was best exemplified in the regulation of the E-cadherin gene. Indeed, we uncovered a regulatory cascade whereby p110 CUX1 binds to the snail and slug gene promoters, activates their expression, and then cooperates with these transcription factors in the repression of the E-cadherin gene, thereby causing disorganization of cell-cell junctions.

Non-Mitogenic Human Acidic Fibroblast Growth Factor Reduces Retinal Degeneration Induced by Sodium Iodate

To investigate the protective effects of non-mitogenic human acidic fibroblast growth factor on retinal degeneration induced by NaIO(3) in rats. Retinal degeneration was induced in adult male Wistar rats via caudal-vein injection of 1% NaIO(3) at 50 mg/kg. One h after NaIO(3) treatment, the right eyes received intravitreal injection of 2.5 microg nm-haFGF in 10 microL saline and the left eyes received saline alone as vehicle-treated eyes. Retinal function in rats was evaluated by electroretinogram (ERG) before injection and 1, 7, and 21 days postinjection. Additional rat eyes were enucleated 7 and 21 days postinjection, fixed, and processed for histological examination. A model of retinal degeneration in rat was established successfully using NaIO(3) injection. Significant decreases in both ERG a- and b-wave amplitudes were detected in NaIO(3)-injected rats when compared with the normal animals (P < 0.05) on day 7 postinjection. Importantly, at the seventh day after intravitreal nm-haFGF treatment on NaIO(3)-injected rats, the nm-haFGF-treated eyes showed a significant improvement in the ERG amplitudes of both a- and b-waves when compared with vehicle-treated eyes (P < 0.05). In addition, the disruptions of photoreceptor outer segments and the retinal pigment epithelium monolayer were much less frequently observed in the nm-haFGF-treated eyes than the vehicle-treated eyes, and the outer nuclear layer thickness in the nm-haFGF-treated eyes was similar to that of the normal eyes. Intravitreal delivery of nm-haFGF appears to have neuroprotective effect on retinal degeneration induced by NaIO(3).

Transplantation of bone-marrow derived mesenchymal stem cells to treat rat retinal degeneration

Objective To observe the effects of subretinal transplantation of rat mesenchymal stem cells (rMSCs) on Sodium Iodate (SI)-induced retinal degeneration.Methods One hundred and twenty Brown-Norway (BN) rats were divided into three groups including SI injection group,rMSCs transplantation group and normal control group,each with 40 rats.The retinal degeneration was induced by caudal vein injection of SI.The retinal pigment epithelium(RPE)and neural retinal were evaluated by ocular fundus photograph,fluorescein fundus angiography (FFA),electroretinogram (ERG) and histological approach,and TUNEL(terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling).CM-Dilprelabeled primary rMSCs were transplanted into the subretinal space of Sl-induced rats.The survival,integration,and differentiation of rMSCs were observed between 14 day to 60 day after the transplantation.Results The rat retinal function was gradually reduced afterl4 days of SI injection,with a time-dependent manner.After the RPE cells were damaged,the outer segments of photoreceptors became disrupted and shortened until karyopyknosis.The nuclear morphology and positive TUNEL labeling indicated that the death of photoreceptor cells was apoptosis.After rMSCs transplantation,CM-DiI labeled donor cells were observed to be scattered in the subretinal space and expressed RPE cell markers.Average amplitude of bwave and Ops (oscillation potential) in ERG improved 27.80%,59.38% respectively after rMSCs transplantation.Conclusions Transplanted rMSCs can survive in subretinal space and differentiate into RPE cells,thus cure SI- induced retinal degeneration. Key words: Stem cells/cytology; Myeloid progenitor cells/transplantation; Mesenchymal stem cell transplantation/methods; Retinal diseases/diagnosis; Animals,laboratory

Anti-tumor effect of Newcastle disease virus strain D817 against nude mouse xenografts of human colon carcinoma

To study the anti-tumor effects of Newcastle disease virus (NDV) strain D817 on human colon carcinoma model in nude mice. The nude mouse model of human colon carcinoma was established by subcutaneous inoculation of human colon cancer LOVO cells. The tumor-bearing mice were given PBS, 5-Fu, high-dose NDV D817, moderate-dose NDV D817 or low-dose NDV D817 via caudal vein injection. The tumor size and weight of mice were measured. The liver damages were examined by histopathology. Apoptosis and necrosis of tumor cells were detected by flow cytometry. The endotumoral content of TNF-alpha was detected using a mouse TNF-alpha ELISA kit. The live virus was detected by hemagglutination (HA) test. The moderate-dose NDV D817 inhibited the tumor growth more apparently than 5-Fu. The tumor growth inhibition rate reached to 48.1%. The liver damage and the weight change caused by NDV were less severe. NDV D817 made an increased apoptosis index and induced production of TNF-alpha. Live virus was not detected in important organs except in the tumor of nude mice by HA test. In the anti-tumor process in nude mice bearing xenografts of human colon carcinoma, a suitable dose of NDV D817 is more safe and effective.

Targeted delivery of levofloxacin-liposomes for the treatment of pulmonary inflammation

The present study systematically studied the intravenous injectable formulation of liposomes loaded with levofloxacin, an amphipathic antibiotic. The aim of the present study was to design passive targeting liposomes, which might improve the antibacterial activity by accumulating in lung and reduce side effects such as neurotoxicity and hematotoxicity associated with direct injection of the drug. Levofloxacin-loaded liposomes were prepared by the ammonium sulfate gradients method. The formulated liposomes were found to be relatively uniform in size (7.424 ± 0.689 μm) with a positive zeta potential (+13.11 ± 1.08 mV). The entrapment efficiency of levofloxacin-loaded liposomes ranged from 82.19% to 86.23%. The administered liposomes were composed of soybean phosphatides, cholesterol, levofloxacin, and sulfate which existed in inner liposomes. In vitro drug release was monitored for up to 3 days, and the release behavior was in accordance with the Weibull equation. The levofloxacin-loaded liposomes exhibited a longer elimination half-life (t1/2β) in vivo compared with the levofloxacin solution after intravenous injection to New Zealand rabbits. The encapsulation of levofloxacin in liposomes also changed its biodistribution in mice after intravenous injection in caudal vein. Liposomal levofloxacin performed significant lung targeting efficiency with area under the concentration–time curve, targeting efficacy (Te), and The intake rate (Re) of lung, all showing obvious increase. In addition, liposomal formulations presented accumulative activity in spleen and liver. Conversely, the biodistribution of liposomal formulation in non-RES sites, such as kidney, brain, heart, and plasma, decreased with descending peak concentration ration (Ce) compared to levofloxacin injection, which potentially resulted in the reduction of the side effects of free drug. These results indicated that the levofloxacin-loaded liposomes were promising passive targeting to lung for pulmonary infection treatment.

Induction of protective antitumor activity of tumor lysate-pulsed dendritic cells vaccine in RM-1 prostate cancer mode

Objective To investigate the antitumor activity of tumor lysate-pulsed dendritic cells vaccine in RM-1 prostate cancer mice model with the survival time of mice calculated and the tumor size measured in DC vaccine therapy. Methods C57BL/6 mice were immunized on the dorsal flank by s.c. inoculation of Lysate-DC, ova-DC, and non-DC on day −7. On day 0, 2×10 6 cells of RM-1 tumor cells (H-2 b) were injected s.c. in C57BL/6 mice pre-treated by s.c. inoculation of modified DCs, correspondingly. DTH assay was performed with modified DCs. In partial test, for the determination of which immune cells were required for antitumor activity, mice were immunodepleted of CD4, CD8, or natural killer (NK) NK1.1 cells with the corresponding monoclonal antibodies. The survival time of nude mice loaded with tumor cells was calculated and the size of tumor measured. Results In RM-1 mice prostate cancer model, immunized with lysate-DC, compared with ova-DC and non-DC, the pre-infection vaccine resulted in 100% clearance of primary tumors, whereas on day 0 of injection vaccine cleared 40-60% of primary tumors. On day 0, C57BL/6 mice (H-2 b) were immunized with Lysate-DC, compared with ova-DC and non-DC by caudal vein injection, then on day 15, RM-1 cells were inoculated. On day 30, average diameters of tumor in different groups of modified DC were 23.7±5.4 mm, 22.1±4.9 mm, 4.3±2.6 mm, respectively. Lysate-DC, compared with ova-DC and non-DC, can greatly depressed RM-1 tumor cell growth ( P<0.01). The mean survival time of C57BL/6 mice in Lysate-DC, ova-DC and non-DC groups were 15.8±2.6, 16.6±3.2, 39.0±5.6, respectively, and there was a significant difference in the mean survival time in lysate-DC group between ova-DC and non-DC group ( P<0.01). DTH test showed that lysate-DC could prime T lymphocyte and elicit tumor antigen specific immune response, and over 80% mice in groups of lysate-DC showed obvious swelling in their foot pad. This response was strengthened with repeating inoculation, whereas DTH response was not seen in control group. In vivo depletion of NK cells resulted in a 40-60% reduction in growth suppression within the primary tumor, and depletion of CD4 + cells resulted in a 20% reduction in growth suppression. Conclusion The tumor lysate-pulsed dendritic cells vaccine could elicit antitumor activity in RM-1 loaded C57BL/6 mice, and prolong the duration of RM-1 loaded C57BL/6 mice. So DC-based immunotherapy with hormone-refractory prostate carcinoma yielded protective immunity, generated efficient cellular antitumor responses, thereby providing further preclinical support for feasible immunotherapy approaches for prostate cancer.

Trichinella spiralis—A potential anti-tumor agent

Murine forestomach carcinoma (cell line MFC), ascitic hepatoma (cell line H22) and sarcoma (cell line S180) solid tumor models were used to test the anti-tumor effect of Trichinella spiralisin vivo. Mice previously infected by oral administration of 400 viable T. spiralis larvae per mouse for 7 days were grafted with various solid tumor cell lines. Other groups of tumor-bearing mice were given caudal vein injection of crude extracts of adult and newborn larvae at 17.5, 35.0 or 70.0mgkg−1. These treatments to inhibit tumor growth were dose-dependent (p<0.05). The anti-proliferative activity of crude T. spiralis extract was examined in vitro at 0.035, 0.070 or 0.140mgml−1 using MFC, H22, S180, human chronic myeloid leukemia cell line (K562) and hepatoma cell line (H7402), tumor cell proliferation in vitro was measured by methyl thiazolium stain and was inhibited in dose-dependent manner (p<0.05). At the same doses, crude T. spiralis extracts induced apoptosis of K562 and H7402 as detected by DNA fragmentation. Cell cycle analysis indicated that crude T. spiralis extracts, at 0.140mgml−1, arrested the cell cycle of K562 and H7402 in G1 or S phase. It is concluded that T. spiralis contains anti-tumor active agent.

Inhibition of Connective Tissue Growth Factor by Small Interfering RNA Prevents Renal Fibrosis in Rats Undergoing Chronic Allograft Nephropathy

Aim Connective tissue growth factor (CTGF) is a highly profibrogenic molecule implicated in renal fibrogenesis. Small interfering RNA (siRNA) is an effective tool to silence gene expression. This study determined whether caudal vein injection of siRNA targeting CTGF inhibited its expression in rat kidneys in vivo, and furthermore whether it protected the kidney from renal fibrosis in chronic allograft nephropathy (CAN). Methods Male inbred Fischer (F344, RT1 lv1) rat renal grafts were orthotopically transplanted into Lewis (LEW, RT1 1) rats following the procedure of Kamada with our modification. At 6 weeks, recipients were divided into siRNA, normal saline (NS), and control siRNA groups, using daily siRNA-targeting CTGF (0.1 mg/kg), or NS, or a control siRNA via caudal vein injection for 14 days. At 4, 6, and 8 weeks, we observed the pathologic changes, expression of CTGF, E-cadherin, collagen I and IV, and anti-smooth muscle actin (α-SMA). Results Serum creatinine level, Banff score, and the expression of CTGF were significantly lower among the siRNA than the NS or the control siRNA groups at 8 weeks ( P < .05). The expressions of collagen I and IV, and α-SMA were also significantly downregulated and E-cadherin was lost in the siRNA versus the NS and control siRNA groups at 8 weeks. Conclusions This study showed that delivery of CTGF siRNA via the caudal vein significantly inhibited expression of CTGF in rat kidneys, effectively preventing fibrosis in CAN. The results suggest that siRNA-targeting of CTGF has the potential to be a novel strategy for amelioration of CAN.

Specific immune against pancreatic cancer induced by dendritic cells pulsed with mutant K-ras peptide

To investigate whether dendritic cells (DCs) pulsed with mutant K-ras peptide (12-Val) can induce efficiently specific anti-tumor immune response against pancreatic cancer. Immature DCs were isolated from the peripheral blood of a volunteer and were pulsed with synthesized mutant K-ras peptide (YKLVVVGAV). When the DCs were matured the expression rate of Kras antigen epitope on the DC's surface was detected by mono antibody (K-ras-12-Val). Autogeneic and homologous T cells were mixed with the mutant K-ras peptide-pulsed DCs. Human pancreatic cancer cells of the line Patu8988 were mixed with cytotoxic T lymphocytes (CTLs) cultured for 5 days, and the killing effects of the CTLs on the cells was assessed by MTT method. Patu8988 cells were injected subcutaneously into nude mice, cancer cells were obtained from the tumor masses and injected subcutaneously into other nude mice to establish mice models of pancreatic cancer. Then 32 mice with pancreatic cancer were randomly divided into 4 equal groups: control group, K-ras specific CTL intra-tumor injection group, CTL caudal vein injection group, and IL-2 activated non-specific CTL intra-tumor injection group. The tumor size was measure regularly. Immunohistochemistry was used to detect the pathological analysis of the transplanted tumors. The mutational epitope (K-ras-12-Val) induced by mutant peptide could be found on the DCs'surface efficiently. After co-incubation with the mature DCs pulsed with tumor antigen the autogeneic T cells were activated, the CD8 T cells accounted for (44.8 +/- 2.1)%. Without damage the normal tissue cells, the killing rate of activated K-ras specific CTLs to the tumor cell when the ratios of CTL: Patu8988 cells were 10:1, 20:1, and 50:1 were (21.2 +/- 1.9)%, (32.4 +/- 2.1)%, and (45.7 +/- 5.3)% respectively, all while the killing efficiency significantly superior to those of the non-specific activated T lymphocyte (all P < 0.05). Eight days after CTL injection into the nude mice the tumor size of the intratumor injection group was (68 +/- 13) mm3, significantly smaller than those of the control group and IL-2 activated non-specific CTL intra-tumor injection group [(87 +/- 14) mm3 and (79 +/- 19) mm3, both P < 0.05]. The survival rates of the nude mice of the K-ras specific CTL intra-tumor injection group, CTL caudal vein injection group, and IL-2 activated non-specific CTL intra-tumor injection group were all significantly higher than that of the control group (all P < 0.05), and the survival rate of the K-ras specific CTL intra-tumor injection group was significantly higher than that of the IL-2 activated non-specific CTL intra-tumor injection group (P < 0.05). Immunohistochemical staining confirmed that K-ras specific CTL had the ability to move toward tumor. DCs pulsed with mutant K-ras peptide (12-Val) induces specific anti-tumor immune response in pancreatic cancer efficiently.

Amelioration effect of Zhenqing Capsule on peripheral neuropathy in type 1 diabetic rats

To investigate the effects of Zhenqing Capsule (ZQC), a compound traditional Chinese herbal medicine, in treating type 1 diabetic rats with peripheral neuropathy. Type 1 diabetes was induced by caudal vein injection of high-dose streptozotocin in 30 male Wistar rats. The thirty diabetic rats were randomly divided into three groups: ZQC-treated group, untreated group and aminoguanidine-treated group. Another group of 10 rats was taken as normal control. After 10-week treatment, the changes of body weight and fasting plasma glucose level were measured, and the serum MDA level and the changes of neurological electrophysiology were analyzed. The samples of sciatic nerve in diabetic rats were taken for morphological observation. The MDA level in type 1 diabetic rats was notably reduced in ZQC-treated group as compared with the untreated group (P<0.01). Compared with the untreated group, ZQC could improve the electrophysiology of sciatic nerve including conduction velocity (P<0.05), latency (P<0.01) and wave amplitude (P<0.05). The nerve myelin staining results showed that segmental demyelination of the nerve fibers in ZQC-treated group was not as serious as that in the untreated group. ZQC can obviously ameliorate the neurological electrophysiological function and the pathological changes of peripheral nerve in type 1 diabetic rats through the removal of free radical and resistance of lipid peroxidation.

Body Distributioin of RGD-mediated Liposome in Brain-targeting Drug Delivery

RGD conjugation liposomes (RGD-liposomes) were evaluated for brain-targeting drug delivery. The flow cytometric in vitro study demonstrated that RGD-liposomes could bind to monocytes and neutrophils effectively. Ferulic acid (4-hydroxy-3-methoxycinnamic, FA) was loaded into liposomes. Rats were subjected to intrastriatal microinjections of 100 units of human recombinant IL-1beta to produce brain inflammation and caudal vein injection of three formulations (FA solution, FA liposome and RGD-coated FA liposome). Animals were sacrificed 15, 30, 60 and 120 min after administration to study the body distribution of the FA in the three formulations. HPLC was used to determine the concentration of FA in vivo with salicylic acid as internal standard. The results of body distribution indicated that RGD-coated liposomes could be mediated into the brain with a 6-fold FA concentration compared to FA solution and 3-fold in comparison to uncoated liposome. Brain targeted delivery was achieved and a reduction in dosage might be allowed.

Recombined CC chemokine ligand 2 into B16 cells induces production of Th2-dominanted cytokines and inhibits melanoma metastasis

This study is aimed to verify whether CCL2 can induce Th2 polarization in vivo and subsequently inhibit tumor metastasis. B16 cells (a murine melanoma cell line) highly expressing CCL2 (CCL2-B16 cells) were obtained by transfection with recombinant plasmid CCL2-pcDNA3. Primary thymocytes were co-cultured with CCL2-B16 cells and STAT-6-mediated Th2 polarization was noticed after co-culture. Caudal vein injection of CCL2-B16 cells effectively inhibited pulmonary metastasis in C57BL/6 mice, but not in nude mice, indicating that T cells play a role in CCL2-induced inhibition of tumor metastasis. We found that high level of CCL2 up-regulated the expression of Th2-related cytokine (IL-4) in tumor microenvironment and increased CD4+, CD8+, and CD45RB+ cells in the peripheral blood and tumor tissues. We also demonstrated that inoculation of mice with CCL2-B16 cells prolonged mice survival time when they were reinjected with wildtype B16 cells, implying that CCL2 can activate immuno-memory in mice. It is concluded that high expression of CCL2 can induce Th2 polarization in tumor microenvironment and can effectively inhibit tumor metastasis, which casts new lights on the role of chemokines in reconstruction of immune surveillance in patients suffering from tumors.

Role of Kupffer cells in acute hemorrhagic necrotizing pancreatitis-associated lung injury of rats

To investigate the role of Kupffer cells (KCs) in acute hemorrhagic necrotizing pancreatitis-associated lung injury (AHNP-LI). Forty-two rats were allocated to four groups [sham operation, AHNP model, gadolinium chloride (GdCl3) pretreatment, GdCl3 control]. In GdCl3 pretreatment group, GdCl3 was administered by caudal vein injection 24 h before the AHNP model induction. Blood from the iliac artery, alveolar macrophages and tissues from the pancreas and lung, were collected in six animals per group 3 and 6 h after acute pancreatitis induction. TNF-alpha, IL-1 of serum, myeloperoxidase (MPO) of lung tissue, NF-kappaB activation of alveolar macrophages were detected. Serum AST and ALT in sham operation group and GdCl3 control group were tested. In addition, histopathological changes of the pancreas and lung were observed under light microscope. MPO of lung tissue and TNF-alpha, IL-1 levels of serum were all reduced significantly in GdCl3 pretreatment group compared to those in AHNP group (P<0.01). NF-kappaB activation of alveolar macrophages was also attenuated significantly in GdCl3 pretreatment group compared to that in AHNP group (P<0.01). The pathological injury of the lung was ameliorated obviously in GdCl3 pretreatment group compared to that in AHNP group. Nevertheless, the serum amylase level did not reduce and injury of the pancreas was not prevented in GdCl3 pretreatment group. Pulmonary injury induced by AHNP is mediated by KC activation and AHNP-LI can be significantly ameliorated by pretreatment with GdCl3 and KCs play a vital role in AHNP-LI.

Cationic albumin-conjugated pegylated nanoparticles as novel drug carrier for brain delivery

In this paper, a novel drug carrier for brain delivery, cationic bovine serum albumin (CBSA) conjugated with poly(ethyleneglycol)–poly(lactide) (PEG–PLA) nanoparticle (CBSA–NP), was developed and its effects were evaluated. The copolymers of methoxy-PEG–PLA and maleimide-PEG–PLA were synthesized by ring opening polymerization of d,l-lactide initiated by methoxy-PEG and maleimide-PEG, respectively, which were applied to prepare pegylated nanoparticles by means of double emulsion and solvent evaporation procedure. Native bovine serum albumin (BSA) was cationized and thiolated, followed by conjugation through the maleimide function located at the distal end of PEG surrounding the nanoparticle's surface. Transmission electron micrograph (TEM) and dynamic light scattering results showed that CBSA–NP had a round and regular shape with a mean diameter around 100 nm. Surface nitrogen was detected by X-ray photoelectron spectroscopy (XPS), and colloidal gold stained around the nanoparticle's surface was visualized in TEM, which proved that CBSA was covalently conjugated onto its surface. To evaluate the effects of brain delivery, BSA conjugated with pegylated nanoparticles (BSA–NP) was used as the control group and 6-coumarin was incorporated into the nanoparticles as the fluorescent probe. The qualitative and quantitative results of CBSA–NP uptake experiment compared with those of BSA–NP showed that rat brain capillary endothelial cells (BCECs) took in much more CBSA–NP than BSA–NP at 37 °C, at different concentrations and time incubations. After a dose of 60 mg/kg CBSA–NP or BSA–NP injection in mice caudal vein, fluorescent microscopy of brain coronal sections showed a higher accumulation of CBSA–NP in the lateral ventricle, third ventricle and periventricular region than that of BSA–NP. There was no difference on BCECs' viability between CBSA-conjugated and -unconjugated pegylated nanoparticles. The significant results in vitro and in vivo showed that CBSA–NP was a promising brain drug delivery carrier with low toxicity.

Influence of Mode of Intravenous Administration and Blood Sample Collection on Rat Pharmacokinetic Data

The influence of the mode of intravenous dosing and blood sample collection on the pharmacokinetics of 4-[(3-methoxyphenyl)-methyl]-2,2,6,6-tetramethyl-1-oxa-4-aza-2,6-disilacyclohexane hydrochloride (I) was studied in the rat. Blood samples obtained from the tail and by exsanguination following injection of the 14C-labeled drug into the caudal vein, the jugular vein, and the heart were analyzed for total radioactivity, and the concentration profiles from the different treatments were compared. Dosing and sampling from the tail vein resulted in significantly different blood levels (and related pharmacokinetic parameters) when compared to other methods, probably attributable to a local depot effect. Intracardiac administration tended to cause higher drug levels in the heart than intravenous doses, although no significant differences were found between the respective blood concentrations. The results showed that caudal vein injection is a simple and adequate method of intravenous administration in rats designated for exsanguinated blood and tissue collection. For serial blood sampling in individual animals, the dose may be given via the jugular vein and the blood collected from the cut tail. These methods require little or no surgical preparations and are particularly suitable for prolonged sampling in studies where a relatively large number of animals are involved.