[Effect of Zhenwu Tang on regulating of "AVP-V2R-AQP2" pathway in NRK-52E cells]

This study was aimed to investigate the effect and mechanism of Zhenwu Tang on AVP-V2R-AQP2 pathway in NRK-52E cells in vitro. Forty eight male SD rats were randomly divided into eight groups with 6 animals in each group. Distilled water or 22.68 g·kg⁻¹·d⁻¹ Zhenwu Tang(calculated by raw drug dosage meter) was given by gavage. Blood samples were collected by cardiac puncture， and the medicated serum was centrifuged from the blood by 3 000 r·min⁻¹. NRK-52E cells were treated with different medicated serum or dDAVP. The condition of cell proliferation was detected by RTCA. The distribution of V2R and AQP2 in cells were detected by immunofluorescence. The expression of V2R， PKA and AQP2 were detected by Western blot and AQP2 mRNA level was detected by real-time PCR. Results showed that the level of AQP2 mRNA(P<0.01) and protein expression of V2R， PKA and AQP2(P<0.05， P<0.01， P<0.05) of Z7d group which was treated with Zhenwu Tang medicated serum for 24 h were significantly higher than that of normal rat serum group. And the expression level of V2R， p-AQP2 and AQP2(P<0.01， P<0.05， P<0.01) of Z7d+dDAVP group were significantly increased comparing to normal rat serum group. The results indicate that the applying of Zhenwu Tang medicated serum could increase the expression level of V2R， PKA and AQP2 which exist in AVP-V2R-AQP2 pathway in NRK-52E， and there is synergistic effect between Zhenwu Tang medicated serum and dDAVP. So the pathway of AVP-V2R-AQP2 may be one of the mechanism for which Zhenwu Tang regulate balance of water transportation.

Identification and Verification of Potential Therapeutic Target Genes in Berberine-Treated Zucker Diabetic Fatty Rats through Bioinformatics Analysis

BACKGROUND

Berberine is used to treat diabetes and dyslipidemia. However, the effect of berberine on specific diabetes treatment targets is unknown. In the current study, we investigated the effect of berberine on the random plasma glucose, glycated hemoglobin (HbA1C), AST, ALT, BUN and CREA levels of Zucker diabetic fatty (ZDF) rats, and we identified and verified the importance of potential therapeutic target genes to provide molecular information for further investigation of the mechanisms underlying the anti-diabetic effects of berberine.

METHODS

ZDF rats were randomly divided into control (Con), diabetic (DM) and berberine-treated (300 mg⋅kg-1, BBR) groups. After the ZDF rats were treated with BBR for 12 weeks, its effect on the random plasma glucose and HbA1C levels was evaluated. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), CREA and OGTT were measured from blood, respectively. The levels of gene expression in liver samples were analyzed using an Agilent rat gene expression 4x44K microarray. The differentially expressed genes (DEGs) were screened as those with log2 (Con vs DM) ≥ 1 and log2 (BBR vs DM) ≥ 1 expression levels, which were the genes with up-regulated expression, and those with log2 (Con vs DM) ≤ -1 and log2 (BBR vs DM) ≤ -1 expression levels, which were the genes with down-regulated expression; the changes in gene expression were considered significant at P<0.05. The functions of the DEGs were determined using gene ontology (GO) and pathway analysis. Furthermore, a protein-protein interaction (PPI) network was constructed using STRING and Cytoscape software. The expression levels of the key node genes in the livers of the ZDF rats were also analyzed using qRT-PCR.

RESULTS

We found that 12 weeks of berberine treatment significantly decreased the random plasma glucose, HbA1C levels and improved glucose tolerance. There was a tendency for berberine to reduce AST, ALT, BUN except increase CREA levels. In the livers of the BBR group, we found 154 DEGs, including 91 genes with up-regulated expression and 63 genes with down-regulated expression. In addition, GO enrichment analysis showed significant enrichment of the DEGs in the following categories: metabolic process, localization, cellular process, biological regulation and response to stimulus process. After the gene screening, KEGG pathway analysis showed that the target genes are involved in multiple pathways, including the lysine degradation, glycosaminoglycan biosynthesis-chondroitin sulfate/dermatan sulfate and pyruvate metabolism pathways. By combining the results of PPI network and KEGG pathway analyses, we identified seven key node genes. The qRT-PCR results confirmed that the expression of the RHOA, MAPK4 and DLAT genes was significantly down-regulated compared with the levels in DM group, whereas the expression of the SgK494, DOT1L, SETD2 and ME3 genes was significantly up-regulated in the BBR group.

CONCLUSION

Berberine can significantly improve glucose metabolism and has a protective effects of liver and kidney function in ZDF rats. The qRT-PCR results for the crucial DEGs validated the microarray results. These results suggested that the RHOA, MAPK4, SGK494, DOT1L, SETD2, ME3 and DLAT genes are potential therapeutic target genes for the treatment of diabetes.

Anti-Apoptotic Effect of Insulin in the Control of Cell Death and Neurologic Deficit after Acute Spinal Cord Injury in Rats

Recent studies confirmed that the new cell survival signal pathway of Insulin-PI3K-Akt exerted cyto-protective actions involving anti-apoptosis. This study was undertaken to investigate the potential neuroprotective effects of insulin in the pathogenesis of spinal cord injury (SCI) and evaluate its therapeutic effects in adult rats. SCI was produced by extradural compression using modified Allen's stall with damage energy of 40 g-cm force. One group of rats was subjected to SCI in combination with the administration of recombinant human insulin dissolved in 50% glucose solution at the dose of 1 IU/kg day, for 7 days. At the same time, another group of rats was subjected to SCI in combination with the administration of an equal volume of sterile saline solution. Functional recovery was evaluated using open-field walking, inclined plane tests, and motor evoked potentials (MEPs) during the first 14 days post-trauma. Levels of protein for B-cell lymphoma/leukemia-2 gene (Bcl-2), Caspase-3, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were quantified in the injured spinal cord by Western blot analysis. Neuronal apoptosis was detected by TUNEL, and spinal cord blood flow (SCBF) was measured by laser-Doppler flowmetry (LDF). Ultimately, the data established the effectiveness of insulin treatment in improving neurologic recovery, increasing the expression of anti-apoptotic bcl-2 proteins, inhibiting caspase-3 expression decreasing neuronal apoptosis, reducing the expression of proinflammatory cytokines iNOS and COX-2, and ameliorating microcirculation of injured spinal cord after moderate contusive SCI in rats. In sum, this study reported the beneficial effects of insulin in the treatment of SCI, with the suggestion that insulin should be considered as a potential therapeutic agent.

Blocking nitrosamine formation with polymers

A set of polymers have been synthesized in order to determine whether polymers containing nitrosation-reactive functional groups could effectively block nitrosamine formation. Polymers containing both hydrophobic backbones [poly[(chloromethyl)styrene], poly(ethylene oxide-co-epichlorohydrin), chloromethylated cross-linked polystyrene] and hydrophilic backbones [poly(ethylenimine) and poly(acryloyl chloride)] have been derivatized with pyrrole, 2,5-dimethylpyrrole, 2-[(methylamino)methyl]pyrrole, or hydroquinone. All of these polymers, as well as PEI itself, are effective at blocking the nitrosation of morpholine by nitrous acid. The hydrophilic polymers are much better able to compete for the available nitrosating agent in aqueous solution than are the hydrophobic polymers. Nevertheless, all of the polymers were highly effective in scavenging nitrous acid from aqueous solution prior to addition of the amine. The reaction products derived from the reactive, polymer-attached functional groups are retained on the polymer and are easily removed from mixtures of chemicals by physical means. Since nitrosamines and other N-nitroso compounds are known to be potent animal carcinogens, this work is of significance in the area of preventive chemical toxicology.

Pyrroles as effective agents for blocking amine nitrosation

The ability of 10 pyrroles to block the acidic nitrosation of morpholine has been determined by using an assay that measures their effectiveness in the presence of a 10-fold excess of amine. The log (% N-nitrosomorpholine) formed is a linear function of blocking agent concentrations ranging from 0.0 to 1.5 times the equivalents of initial nitrite. The negative slopes of these plots allow a ranking of the effectiveness of the blocking agent. Several of the pyrroles have been found to be much more effective than established blocking agents such as ascorbic acid. The following order of blocking ability has been determined: 2,5-dimethylpyrrole = 1-benzyl-2,5-dimethylpyrrole much greater than 4-methylcatechol greater than ascorbic acid = 1,2-phenylenediamine = pyrrole greater than 1,2,5-tribenzylpyrrole = 1-benzylpyrrole = octamethylporphine much greater than ammonium sulfamate = hydrazine = 2,5-diphenylpyrrole much much greater than beta-nicotyrine greater than 2-pyrrolecarboxylic acid. Pyrroles give complex mixtures devoid of N-nitroso compounds upon nitrosation.