A symptom severity questionnaire for patients suffering from functional gastrointestinal disorder: FGI-Checklist.

BACKGROUND AND AIM: A well-validated, comprehensive checklist of functional gastrointestinal (FGI) disorder (FGID) symptom severity for tracking symptom profile changes over time is lacking. We aim to develop and validate a comprehensive symptom severity checklist for FGID. METHODS: A 20-item scale, including both upper and lower gastrointestinal symptoms, was generated to measure the symptom severity commonly found in FGID. Patients who experienced at least monthly symptoms of FGID with negative endoscopy findings were invited to complete the FGI-Checklist, Patient Health Questionaire-9 for assessing depressive symptoms, and Patient Health Questionnaire-15 for assessing somatic symptoms at baseline. A subset of patients who met Rome III diagnostic criteria of gastroesophageal reflux disease, functional dyspepsia, and irritable bowel syndrome received medication treatment for 8-12 weeks and completed the FGI-Checklist again at a follow-up visit. Exploratory factor analysis was performed for subscales formation and psychometric properties were measured. RESULTS: Six hundred and forty-one patients were recruited for current study and 108 (16.8%) of them completed the FGI-Checklist again at follow-up. Exploratory factor analysis identified a five-factor solution accounting for 66.8% of the total variance. The five factors are named esophageal syndrome, reflux syndrome, functional dyspepsia syndrome, nausea and vomiting syndrome, and abdominal and bowel syndrome. The FGI-Checklist total score correlated with Patient Health Questionaire-9 and Patient Health Questionnaire-15 (all P < 0.001), which demonstrated good construct validity. Good item-internal consistency was found (Cronbach's alphas: 0.69-0.87). Responsiveness for reflux syndrome subscale, functional dyspepsia syndrome subscale, and abdominal and bowel syndrome subscale after medication treatment was significant (paired-t-test: all P < 0.01). CONCLUSION: The instrument, Checklist, is valid and reliable.

Glucose lowering effect of transgenic human insulin-like growth factor-I from rice: in vitro and in vivo studies.

BACKGROUND: Human insulin-like growth factor-I (hIGF-I) is a growth factor which is highly resemble to insulin. It is essential for cell proliferation and has been proposed for treatment of various endocrine-associated diseases including growth hormone insensitivity syndrome and diabetes mellitus. In the present study, an efficient plant expression system was developed to produce biologically active recombinant hIGF-I (rhIGF-I) in transgenic rice grains. RESULTS: The plant-codon-optimized hIGF-I was introduced into rice via Agrobacterium-mediated transformation. To enhance the stability and yield of rhIGF-I, the endoplasmic reticulum-retention signal and glutelin signal peptide were used to deliver rhIGF-I to endoplasmic reticulum for stable accumulation. We found that only glutelin signal peptide could lead to successful expression of hIGF-I and one gram of hIGF-I rice grain possessed the maximum activity level equivalent to 3.2 micro molar of commercial rhIGF-I. In vitro functional analysis showed that the rice-derived rhIGF-I was effective in inducing membrane ruffling and glucose uptake on rat skeletal muscle cells. Oral meal test with rice-containing rhIGF-I acutely reduced blood glucose levels in streptozotocin-induced and Zucker diabetic rats, whereas it had no effect in normal rats. CONCLUSION: Our findings provided an alternative expression system to produce large quantities of biologically active rhIGF-I. The provision of large quantity of recombinant proteins will promote further research on the therapeutic potential of rhIGF-I.

Functional dyspepsia susceptibility is associated with TGFB1 gene polymorphisms (RS4803455, RS1800469) in H pylori-negative Chinese population.

BACKGROUND: We previously published that altered expression of gastric TRPV1, BDNF, and peripheral cytokines was present in patients with functional dyspepsia. We herein examine whether genetic predisposition in altered biomarkers influences dyspeptic, sleep, and mood symptoms in patients with FD without previous infection. METHODS: Consecutive adult FD patients (Rome III) with no recent history of gastroenteritis and asymptomatic age- and sex-matched healthy controls were recruited for upper endoscopy. Subjects with GERD and IBS as predominant symptoms, diabetes mellitus, current or previous H pylori infection, psychiatric illness, and recent use of NSAID or PPI were excluded. The genetic associations with dyspeptic symptoms, sleep quality, and mood symptoms were evaluated. Genetic polymorphisms in TRPV1, TGFB1, TNF, COMT, BDNF, IL6, IL8, IL10, and IL12 were analyzed. KEY RESULTS: Twenty-nine male FD patients and 104 female FD patients were age matched (±3 years) with 81 healthy subjects. All had postprandial distress syndrome (PDS) as predominant subtype (PDS: 130, EPS: 3). SNPs in TGFB1 showed significant associations in dyspeptic patients after age and sex adjustment [for RS4803455: in the codominant model (C/A, OR = 0.34 (0.18-0.65), P = .004); in the dominant model (genotype C/C vs C/A-A/A, OR = 0.42 (0.23-0.77), P = .004); and in the overdominant model (genotype C/C-A/A vs C/A, OR = 0.38 (0.21-0.70), P < .001)] [for RS1800469: in dominant model (genotype A/A vs A/G-G/G, OR = 0.52 (0.27-0.99), P = .043)]. A allele in RS4803455 was associated with higher HADS depression score (P = .05) and epigastric burning sensation(P = .01). CONCLUSIONS AND INFERENCES: Our data showed that dyspeptic patients predispose genetic difference in TGFB1 which may influence the severity of dyspepsia.

Microtubule network is required for insulin-induced signal transduction and actin remodeling.

Both microtubule and actin are required for insulin-induced glucose uptake. However, the roles of these two cytoskeletons and their relationship in insulin action still remain unclear. In this work, we examined the morphological change of microtubule/actin and their involvement in insulin signal transduction using rat skeletal muscle cells. Insulin rapidly led to microtubule clustering from ventral to dorsal surface of the cell. Microtubule filaments were rearranged to create space where new actin structures formed. Disruption of microtubule prevented insulin-induced actin remodeling and distal insulin signal transduction, with reduction in surface glucose transporter isoform 4 (GLUT4) and glucose uptake. Though microtubule mediated actin remodeling through PKCζ, reorganization of microtubule depended on tyrosine phosphorylation of insulin receptor, the mechanism is different from insulin-induced actin remodeling, which relied on the activity of PI3-kinase and PKCζ. We propose that microtubule network is required for insulin-induced signal transduction and actin remodeling in skeletal muscle cells.

The pivotal role of protein kinase C zeta (PKCzeta) in insulin- and AMP-activated protein kinase (AMPK)-mediated glucose uptake in muscle cells.

Insulin and AMP-activated protein kinase (AMPK) signal pathways are involved in the regulation of glucose uptake. The integration of signals between these two pathways to maintain glucose homeostasis remains elusive. In this work, stimulation of insulin and berberine conferred a glucose uptake or surface glucose transporter 4 (GLUT4) translocation that was less than simple summation of their effects in insulin-sensitive muscle cells. Using specific inhibitors to key kinases of both pathways and PKCzeta small interference RNA, protein kinase C zeta (PKCzeta) was found to regulate insulin-stimulated protein kinase B (PKB) activation and inhibit AMPK activity on dorsal cell surface. In the presence of berberine, PKCzeta controlled AMPK activation and AMPK blocked PKB activity in perinuclear region. The inhibition effect of PKCzeta on AMPK activation or the arrestment of PKB activity by AMPK still existed in basal condition. These results suggest that there is antagonistic regulation between insulin and AMPK signal pathways, which is mediated by the switch roles of PKCzeta.

Berberine modulates insulin signaling transduction in insulin-resistant cells.

Berberine has been shown to have insulin-sensitizing effect, but the molecular mechanism underlying remains elusive. In this work, we investigated the effect of berberine on insulin-induced signal transduction and glucose uptake in both insulin-sensitive and insulin-resistant rat skeletal muscle cells. Berberine increased the activity of AMPK and PKCzeta and AS160 phosphorylation in normal cells, but had little effect on PKB activation. In insulin-resistant state, berberine exhibited synergistic effect on insulin-induced glucose uptake and GLUT4 translocation. Berberine improved insulin-induced tyrosine-phosphorylation of IRS-1 and the recruitment of p85 to IRS-1. These changes were accompanied by enhancement in insulin-induced PKCzeta and PKB activity and actin remodeling. The ameliorated insulin signal transduction was related to the inhibition of mTOR by berberine, which attenuated serine-phosphorylation of IRS-1. These results suggest that berberine may overcome insulin resistance via modulating key molecules in insulin signaling pathway, leading to increased glucose uptake in insulin-resistant cells.