Effects of Robuvit® on the progression of non-alcoholic fatty liver disease.

BACKGROUND: The aim of this study was to evaluate the effects of Robuvit® in preventing the progression of chronic hepatitis (CH) in non-alcoholic fatty liver disease (NAFLD) which encompasses the entire spectrum of fatty liver disease, from isolated steatosis to non-alcoholic steatohepatitis (NASH). METHODS: One group of patients followed the Standard management (SM) and were assigned as controls while the supplementation group followed the SM and additionally took 2 Robuvit® capsules daily for 3 months (200 mg/day). RESULTS: 34 subjects with NAFLD were included in the study. The two groups completing 90 days were comparable at baseline with 18 being supplemented with Robuvit® and 16 in the control group. The tolerability was very good, and no side effects were observed with the supplement. Fasting glucose levels were significantly lower after 3 months with Robuvit® (P<0.05) compared to controls. The increased serum aspartate aminotransferase levels (AST), considered the key metabolic value in these patients, decreased significantly with Robuvit® (P<0.05) compared to controls. Serum alanine aminotransferase levels (ALT) also decreased significantly with the supplement compared to controls (P<0.05). Platelet count and albumin levels improved significantly with Robuvit® (P<0.05) in comparison to standard management. No other significant changes were observed. The APRI score (the AST/platelet ratio index) was also decreased with the supplementation compared to controls (P<0.05). A high APRI score provides an estimate of the possibility of the liver to develop fibrosis and eventually cirrhosis. After Robuvit® supplementation, the ultrasound characterization showed a significant decrease in the size of the liver in association with a lower echogenicity, which represents less fibrotic changes due to collagen accumulation. CONCLUSIONS: Robuvit® improved liver function in NAFLD and prevented progression to liver fibrosis by improving hepatic metabolism in a relatively short period of time. Numerous people are affected by NAFLD, many of them with subclinical symptoms. But to date, there are no specific, definite treatment options. Prolonged evaluations of Robuvit® in a larger group of subjects is suggested.

Operational Modes and Speed Considerations of an Acoustic Droplet Dispenser for Mass Spectrometry.

Acoustic ejection mass spectrometry is a recently developed concept in which low nanoliter-volume sample droplets are acoustically dispensed from microtiter plate wells into a continuous fluid transfer open-port interface for subsequent ionization at atmospheric pressure. This manuscript focuses on the acoustic droplet dispensing component of a prototype system, in particular the well-to-well sampling speed, droplet volume calibration, precision, reproducibility, and various modes of operation this device enables. A new method to measure the volume of individually dispensed droplets is presented to both aid method validation and potentially assist in the tuning of acoustic dispense parameters for samples having a wide range of viscosities and surface tensions. Acoustic dispensing modes of operation discussed are high-speed, well-to-well dispensing of individual nanoliter-scale droplets from microtiter plates, including the first demonstration of 1536-well compatibility using this approach. Multiple nanoliter-volume droplets per sampling event to increase detection dynamic range is described, and a "continuous infusion" mode to provide a low sample consumption sustained steady-state signal for analyte detection optimization, improved ion statistics and signal-to-noise ratio (S/N), or time for in-depth tandem mass spectrometry of the components in a sample is presented. The concept of "bar coding" using combinations of dispensed droplet patterns to register well-plate position to specific mass spectral signals is introduced, as well as judicious well-plate sample layout to enable assay "multiplexing" as a means to maximize well-to-well sample analysis throughput, is also demonstrated.

Novel technique for retroperitoneal implantation of telemetry transmitters for physiologic monitoring in Göttingen minipigs (Sus scrofa domesticus).

Telemetric monitoring of physiologic parameters in animal models is a critical component of chemical and biologic agent studies. The long-term collection of neurobehavioral and other physiologic data can require larger telemetry devices. Furthermore, such devices must be implanted in a location that is safe, well-tolerated, and functional. Göttingen minipigs (Sus scrofa domesticus) present an ideal large animal model for chemical agent studies due to their relatively small size, characterized health status, and ease of training and handling. We report an effective approach to implanting a novel device to measure transthoracic impedance to approximate respiratory tidal volume and rate in Suidae. We tested the approach using 24 male Göttingen minipigs. A ventral midline abdominal incision extending from the umbilicus to the prepuce was followed by a paramedian incision of the parietal peritoneum and dorsal blunt dissection to create a retroperitoneal pocket. The device was anchored inside the pocket to the internal abdominal musculature with 3-0 nonabsorbable suture, biopotential leads were routed through the abdominal musculature, and the pocket was closed with 3-0 absorbable suture. Paired biopotential leads were anchored intermuscularly at the level of the seventh rib midway between spine and sternum bilaterally to provide surrogate data for respiratory function. Postoperative recovery and gross pathology findings at necropsy were used to assess safety and refine the surgical procedure. Results demonstrated that this procedure permitted effective monitoring of complex physiologic data, including transthoracic impedance, without negatively affecting the health and behavior of the animals.

Use of operant performance to guide and evaluate medical treatment in an adult male cynomolgus macaque (Macaca fascicularis).

A 6-y-old male cynomolgus macaque presented with noticeable swelling of the left forearm and signs of discomfort, as indicated by nonuse of the arm even in a behavioral task that he previously had been well-motivated to perform. Examination under anesthesia revealed lacerations to the arm. Radiography of the forearm showed no fractures, indicating that the damage was limited to soft tissue. The daily operant behavioral session assessed the amount of force the monkey emitted when touching the screen with the affected arm and how long each touch was sustained. We then used these parameters (force and duration of touch) as objective measures of putative pain relief and recovery of function to guide the medical treatment. The affected monkey received ketoprofen, buprenorphine, or their combination but continued to perform poorly during daily operant behavioral sessions. Only after treatment with dexamethasone did performance return to preinjury levels, suggesting inflammation near the radial or ulnar nerve. These findings indicate that performance of a trained operant task performance can be useful in guiding medical treatment, evaluating pain relief, and objectively monitoring health in laboratory animals.

Online coupling of reverse-phase and hydrophilic interaction liquid chromatography for protein and glycoprotein characterization.

We have developed a novel system for coupling reverse-phase (RP) and hydrophilic interaction liquid chromatography (HILIC) online in a micro-flow scheme. In this approach, the inherent solvent incompatibility between RP and HILIC is overcome through the use of constant-pressure online solvent mixing, which allows our system to perform efficient separations of both hydrophilic and hydrophobic compounds for mass spectrometry-based proteomics applications. When analyzing the tryptic digests of bovine serum albumin, ribonuclease B, and horseradish peroxidase, we observed near-identical coverage of peptides and glycopeptides when using online RP-HILIC--with only a single sample injection event--as we did from two separate RP and HILIC analyses. The coupled system was also capable of concurrently characterizing the peptide and glycan portions of deglycosylated glycoproteins from one injection event, as confirmed, for example, through our detection of 23 novel glycans from turkey ovalbumin. Finally, we validated the applicability of using RP-HILIC for the analysis of highly complex biological samples (mouse chondrocyte lysate, deglycosylated human serum). The enhanced coverage and efficiency of online RP-HILIC makes it a viable technique for the comprehensive separation of components displaying dramatically different hydrophobicities, such as peptides, glycopeptides, and glycans.

N-linked glycoprotein analysis using dual-extraction ultrahigh-performance liquid chromatography and electrospray tandem mass spectrometry.

Although reverse-phase liquid chromatography (RP-LC) is a common technique for peptide separation in shotgun proteomics and glycoproteomics, it often provides unsatisfactory results for the analysis of glycopeptides and glycans. This bias against glycopeptides makes it difficult to study glycoproteins. By coupling mass spectrometry (MS) with a combination of RP-LC and normal-phase (NP)-LC as an integrated front-end separation system, we demonstrate that effective identification and characterization of both peptides and glycopeptides mixtures, and their constituent glycan structures, can be achieved from a single sample injection event.

Multiple reaction monitoring as a method for identifying protein posttranslational modifications.

The activity of many transcriptional regulators is significantly altered by posttranslational modifications of specific sites. For example, the activity of the muscle-restricted transcription factor family myocyte enhancer factor 2 (MEF2) is tightly controlled by phosphorylation. This modification is responsible for either an increase or a decrease in transcriptional activity, depending on the specific amino acid residues that are phosphorylated by signal-dependent kinases. Although mass spectrometry-based methods, such as precursor ion and neutral loss scans, are extremely useful for identifying unknown phosphopeptides from a complex mixture, they do not take advantage of any prior knowledge about the protein being investigated. Quite often a significant amount of information is available. This may include the primary sequence, type of phosphorylation (serine/threonine vs. tyrosine), or predicted phosphoacceptor sites (consensus peptide that is targeted by a kinase). This information can be used to predict precursor and fragment ion m/z values for a multiple reaction monitoring (MRM) experiment. By using these highly sensitive MRM experiments to trigger dependent product ion scans on a hybrid quadrupole linear ion-trap instrument, we were able to identify low levels of phosphorylation of MEF2A (a member of the MEF2 family), and alpha-casein. This method of monitoring protein phosphorylation at specific phosphoacceptor sites may prove useful in understanding the physiological regulation of protein function.

Phosphorylation motifs regulating the stability and function of myocyte enhancer factor 2A.

The phosphorylation status of the myocyte enhancer factor 2 (MEF2) transcriptional regulator is a critical determinant of its tissue-specific functions. However, due to the complexity of its phosphorylation pattern in vivo, a systematic inventory of MEF2A phosphorylation sites in mammalian cells has been difficult to obtain. We employed modern affinity purification techniques, combined with mass spectrometry, to identify several novel MEF2 phosphoacceptor sites. These include an evolutionarily conserved KSP motif, which we show is important in regulating the stability and function of MEF2A. Also, an indirect pathway in which a protein kinase casein kinase 2 phosphoacceptor site is phosphorylated by activation of p38 MAPK signaling was documented. Together, these findings identify several novel aspects of MEF2 regulation that may prove important in the control of gene expression in neuronal and muscle cells.

Sequencing of argentinated peptides by means of matrix-assisted laser desorption/ionization tandem mass spectrometry.

Argentinated peptide ions are formed in abundance under matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) conditions in the presence of Ag+ ions. These argentinated peptide ions are fragmented facilely under MALDI-MS/MS conditions to yield [b(n) + OH + Ag]+, [b(n) - H + Ag]+ and [a(n) - H + Ag]+ ions that are indicative of the C-terminal sequence. These observations parallel those made earlier under electrospray MS conditions (Chu, I. K; Guo, X.; Lau, T.-C.; Siu, K W. M. Anal. Chem. 1999, 71, 2364-2372). A mixed protonated and argentinated tryptic peptide map was generated from 37 fmol of bovine serum albumin (BSA) using MALDI-MS. MALDI-MS/MS data from four argentinated peptides at a protein amount of 350 fmol unambiguously identified the protein as BSA. Sequence-tag analysis of two argentinated tryptic peptides was used to identify unambiguously myocyte enhancer factor 2A, which had been recombinantly expressed in a bacterial cell line.

Composition and function of AP-1 transcription complexes during muscle cell differentiation.

The role of activating protein-1 (AP-1) in muscle cells is currently equivocal. While some studies propose that AP-1 is inhibitory for myogenesis, others implicate a positive role in this process. We tested whether this variation may be due to different properties of the AP-1 subunit composition in differentiating cells. Using Western analysis we show that c-Jun, Fra-2, and JunD are expressed throughout the time course of differentiation. Phosphatase assays indicate that JunD and Fra-2 are phosphorylated in muscle cells and that at least two isoforms of each are expressed in muscle cells. Electrophoretic mobility shift assays combined with antibody supershifts indicate the appearance of Fra-2 as a major component of the AP-1 DNA binding complex in differentiating cells. In this context it appears that Fra-2 heterodimerizes with c-Jun and JunD. Studying the c-jun enhancer in reporter gene assays we observed that the muscle transcription factors MEF2A and MyoD can contribute to robust transcriptional activation of the c-jun enhancer. In differentiating muscle cells mutation of the MEF2 site reduces transactivation of the c-jun enhancer and MEF2A is the predominant MEF2 isoform binding to this cis element. Transcriptional activation of an AP-1 site containing reporter gene (TRE-Luc) is enhanced under differentiation conditions compared with growth conditions in C2C12 muscle cells. Further studies indicate that Fra-2 containing AP-1 complexes can transactivate the MyoD enhancer/promoter. Thus, an AP-1 complex containing Fra-2 and c-Jun or JunD is consistent with muscle differentiation, indicating that AP-1 function during myogenesis is dependent on its subunit composition.