From glucose sensing to exocytosis: takes from maturity onset diabetes of the young.

Monogenic diabetes gave us simplified models of complex molecular processes occurring within ß-cells, which allowed to explore the roles of numerous proteins from single protein perspective. Constellation of characteristic phenotypic features and wide application of genetic sequencing techniques to clinical practice, made the major form of monogenic diabetes - the Maturity Onset Diabetes of the Young to be distinguishable from type 1, type 2 as well as neonatal diabetes mellitus and understanding underlying molecular events for each type of MODY contributed to the advancements of antidiabetic therapy and stem cell research tremendously. The functional analysis of MODY-causing proteins in diabetes development, not only provided better care for patients suffering from diabetes, but also enriched our comprehension regarding the universal cellular processes including transcriptional and translational regulation, behavior of ion channels and transporters, cargo trafficking, exocytosis. In this review, we will overview structure and function of MODY-causing proteins, alterations in a particular protein arising from the deleterious mutations to the corresponding gene and their consequences, and translation of this knowledge into new treatment strategies.

C-type natriuretic peptide stimulates osteoblastic proliferation and collagen-X expression but suppresses fibroblast growth factor-23 expression in vitro.

BACKGROUND: The effects of C-type natriuretic peptide (CNP) and fibroblast growth factor (FGF)-23 appear to oppose each other during the process of bone formation, whereas few studies exist on the interaction between CNP and FGF-23. The main objective of the present study is to probe whether CNP is directly responsible for the regulation of osteoblast or via antagonizing FGF-23. METHODS: Osteoblasts were cultured in the absence or presence of CNP (0, 10, and 100 pmol/L) for 24 h, 48 h and 72 h, respectively. RESULTS: The findings of the present study indicated that: (1) CNP significantly stimulated osteoblastic proliferation and collagen (Col)-X expression; (2) both osteoblastic (osteocalcin, procollagen type I carboxy-terminal propeptide, total alkaline phosphatase and bone-specific alkaline phosphatase) and osteolytic (tartrate-resistant acid phosphatase and cross-linked carboxyterminal telopeptide of type I collagen) bone turnover biomarkers were up-regulated by CNP in osteoblasts; (3) FGF-23 mRNA and protein were significantly down-regulated at 24 h by CNP in osteoblasts, but the expression of FGF receptor-1/Klotho had no significant change. CONCLUSIONS: CNP stimulates osteoblastic proliferation and Col-X expression via the down-regulation of FGF-23 possibly in vitro. However, the specific mechanisms of the interaction between CNP and FGF-23 in osteoblasts are still unclear according to our findings. A further study on osteoblasts cultured with CNP and FGF-23 inhibitor will be undertaken in our laboratory.

Clinical observation of noncoronary cardiac abnormalities in Chinese children with Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) is an acute, self-limited vasculitis. Coronary artery aneurysm (CAA) serves as a major contributor to the long-term prognosis of KD. In addition, acute KD usually also leads to several kinds of noncoronary cardiac abnormalities (NCA) involving the pericardium, myocardium and endocardium. MATERIALS AND METHODS: A total of 142 Chinese children with KD were recruited from July 2015 to April 2018. Blood samples were collected at 24 hours pre-intravenous immunoglobulin (IVIG) therapy. Several inflammatory mediators and biomarkers for acute myocardial infarction were detected. Echocardiography and electrocardiography (ECG) were performed. RESULTS: Plasma white blood cell counts (WBC) were significantly increased in patients with IVIG-nonresponsive KD when compared with their IVIG-responsive counterparts. A total of 106 children (74.65%) suffered from NCA, including 8 patients (5.63%) with pericardial effusion, 23 patients (16.20%) with acute myocarditis, 101 patients (71.13%) with valvular regurgitation and 8 patients (5.63%) with abnormal ECG. No significant differences were observed in the distribution of clinical classification and the response to IVIG therapy regardless of NCA exhibited or not. CONCLUSIONS: Noncoronary cardiac abnormalities is almost universal in acute KD and mainly manifests as valvular regurgitation. However, it has no influence on clinical classification and the response to IVIG therapy.

Association of the infectious triggers with childhood Henoch-Schonlein purpura in Anhui province, China.

BACKGROUND: Although the specific etiology of Henoch-Schonlein purpura (HSP) is still unknown, several kinds of infectious triggers have been proved to participate in its pathogenesis. The objectives of present study were to analyze the association of the infectious triggers with childhood HSP in Anhui province, China. METHODS: 1200 HSP children were recruited from January 2015 to December 2017. Serum antistreptolysin O titer, TORCH, Epstein-Barr virus, helicobacter pylori (HP), Mycoplasma antibodies (MP-Ab), tubercle bacillus antibody (TB-Ab), respiratory pathogens (legionella pneumophila, chlamydia pneumoniae, adenovirus, respiratory syncytial virus, influenza A virus, influenza B virus, rickettsia, parainfluenza virus) were determined. Patients' histories were obtained by interviews and questionnaires. RESULTS: The annual incidence of HSP was 8.13-9.17 per 100,000. HSP occurred more commonly in spring and winter than in summer with an obvious west-to-east gradient. On admission, several potential infections were identified in 611 cases (50.92%). The infectious agents including streptococcus, HP, MP, parainfluenza, respiratory syncytial virus, TB and toxoplasma gondii were identified in 205 cases (17.08%), 71 cases (5.92%), 58 cases (4.83%), 6 cases (0.5%), 1 case (0.08%), 1 case (0.08%) and 1 case (0.08%) respectively. 123 cases (10.25%) relapsed or recurred more than one time; the mean number was 2.92, and the mean interval was 11.4 weeks. The infection was the most frequent trigger regardless of clinical phenotypes and relapse/recurrence. Symptomatic treatment plus adjunctive anti-infectious agents could significantly improve the remission rate of purpura in the infectious cases (x2=24.60, p<0.01). CONCLUSIONS: Streptococcus is the most frequent infectious agent in HSP children regardless of clinical phenotype or relapse/recurrence. The complete elimination of infectious triggers may help relieve cutaneous purpura.

Hepatic dysfunction secondary to Kawasaki disease: characteristics, etiology and predictive role in coronary artery abnormalities.

Coronary artery abnormalities (CAAs) are prominent during the acute Kawasaki disease (KD) episode and represent the major contributors to the long-term prognosis. Several meta-analysis and published scoring systems have identified hepatic dysfunction as an independent predictor of CAA risks. The medical records of 210 KD children were reviewed. Blood samples were collected from all subjects at 24 h pre-therapy and 48 h post-therapy, respectively. Liver function test (LFT) and inflammatory mediators were detected. Multivariate logistic regression analysis was conducted to identify the reliable biomarkers predicting whether CAAs existed or not in KD patients. 90.95% of KD patients had at least 1 abnormal LFT. Hypoalbuminemia was the most prevalent type of hepatic dysfunction, followed by elevated aspartate aminotransferase, low TP, low A/G and hyperbilirubinemia, respectively. The elevated inflammatory mediators (procalcitonin and C-reactive protein) and moderate dose of aspirin played a synthetic role in hepatic dysfunction secondary to KD. However, LFT presented no significant differences between infectious and noninfectious conditions. By a multivariate analysis, a lower albumin/globulin ratio (A/G, OR 13.50, 95% CI 3.944-46.23) served as an independent predictor of CAAs and had a sensitivity of 56.25%, and a specificity of 61.11% at a cutoff value of < 1.48. In conclusion, hepatic dysfunction is a common complication during the acute KD episode, characterized by elevated serum liver enzymes, hypoalbuminemia and hyperbilirubinemia. Systemic inflammation and aspirin, rather than infectious agents, are both the major contributors of hepatic dysfunction secondary to KD. A lower A/G serves as an independent predictor of CAAs.

The time option of IVIG treatment is associated with therapeutic responsiveness and coronary artery abnormalities but not with clinical classification in the acute episode of Kawasaki disease.

BACKGROUND: In the last decade, incomplete Kawasaki disease (KD), intravenous immunoglobulin (IVIG) non-response and coronary artery abnormalities (CAA) have experienced the increasing trends in China. In addition, the enhancement of pediatricians' awareness may also raise the diagnostic rate of incomplete KD and stimulate more aggressive initial therapy in the acute episode of KD. Given this background, we hypothesize that the time option of IVIG treatment should be in parallel with peak time of systemic inflammation; either earlier or later IVIG treatment may affect the clinical classification, therapeutic responsiveness and CAA occurrence in KD patients. Therefore, the major objective of the present study is to identify whether the time option of IVIG treatment could be associated with the clinical classification, therapeutic responsiveness and CAA occurrence in the acute episode of KD. MATERIALS AND METHODS: A total of 153 children with KD were recruited between July 2015 and May 2018. All patients received the standard therapy of KD, including a single infusion of IVIG (2 g/kg) and aspirin (30-50 mg/kg/d). Blood samples were collected from all subjects within 24 h pre-IVIG treatment, respectively. Echocardiography was performed during the period from 2 days to 14 days after IVIG treatment. RESULTS: (1) The clinical classification presented no significant heterogenicity among different treatment time (x2 = 1.59, p > 0.05) (2) Eleven KD patients resisted to IVIG treatment and 7 of them (63.60%) received the initial IVIG dose on day 5 and 6. (3) The distribution of CAA onset was subjected to a significant difference according to timing option of IVIG treatment (x2 = 11.94, p < 0.05). CONCLUSIONS: The time option of IVIG treatment is associated with therapeutic responsiveness and CAA but not with clinical classification in the acute episode of KD.

Interleukin-6 is prone to be a candidate biomarker for predicting incomplete and IVIG nonresponsive Kawasaki disease rather than coronary artery aneurysm.

Kawasaki disease (KD) is an acute, systemic vasculitis and occurs mainly in childhood. Interleukin-6 (IL-6) is a pleiotropic cytokine synthesized predominantly by neutrophils and monocytes/macrophages and plays an important role in systemic inflammatory disease. However, a little information is currently available on the relationship of serum IL-6 with conventional inflammatory mediators, clinical classification, IVIG response and coronary artery aneurysm (CAA). 165 Chinese children with KD were enrolled and divided into six subgroups, including complete KD, incomplete KD, IVIG-responsive KD, IVIG-nonresponsive KD, coronary artery noninvolvement KD and coronary artery involvement KD. Blood samples were collected from all subjects within 24-h pre- and 48-h post-IVIG therapy, respectively. Serum IL-6 and conventional inflammatory mediators were detected. (1) Serum IL-6 markedly increased in the acute phase of KD, whereas declined to normal after IVIG therapy; it was positively correlated with C-reactive protein and erythrocyte sedimentation rate. (2) Serum IL-6 was significantly elevated in patients with incomplete KD when compared with their complete counterparts. The area under receiver operating characteristic curve (AUC) value for serum IL-6 in prediction of incomplete KD was 0.596, and the estimated sensitivity and specificity were 77.80% and 54.40% with a cutoff of IL-6 > 13.25 pg/ml, respectively. (3) Serum IL-6 was significantly elevated in patients with IVIG-nonresponsive KD when compared with their IVIG-responsive counterparts; the AUC value for serum IL-6 in prediction of IVIG-nonresponsive KD was 0.580, and the estimated sensitivity and specificity were 60.00% and 66.30% with a cutoff of IL-6 > 26.40 pg/ml, respectively. (4) No significant differences in IL-6 were found between KD patients with and without CAA. IL-6 is prone to be a candidate biomarker for predicting incomplete and IVIG nonresponsive KD rather than CAA.

Predisposing factors of childhood Henoch-Schönlein purpura in Anhui province, China.

Henoch-Schönlein purpura (HSP) is a common autoimmune vasculitis in childhood. The detailed pathogenesis of HSP is still unclear, whereas several types of predisposing factors have been proved to be the initial step. The objectives of present study were to analyze the distribution of predisposing factors, association of the predisposing factors with clinical manifestations and HSP relapse/recurrence. 1200 children with HSP were recruited between January 2015 and December 2017. We reviewed their laboratory tests and medical histories associated with HSP onset. The annual incidence of HSP was 8.13-9.17 per 100 000 in Anhui province. HSP occurred more commonly in spring and winter than in summer with an obvious west-to-east gradient. Cutaneous purpura was the most prevalent manifestation (100%), followed by arthritis/arthralgias (43.67%), abdominal pain (40.17%) and renal involvement (18.17%). On admission, series of potential infections were identified in 611 patients (50.92%). The histories of allergy, injury, surgery, vaccination and tick bite were declared by 231 patients (19.25%), 15 patients (1.25%), 12 patients (1.00%), 4 patients (0.33%) and 3 patients (0.25%), respectively. However, predisposing factors could not be identified in 521 children with HSP (43.42%) yet. 123 cases (10.25%) relapsed or recurred more than one time; the mean number was 2.92, and the mean interval was 11.4 weeks. The infection is the most frequent predisposing factor regardless of clinical phenotypes and relapse/recurrence, whereas the clinical manifestations exhibit an obvious heterogenicity according to different predisposing factors.

C-Type Natriuretic Peptide Dampens Fibroblast Growth Factor-23 Expression Through MAPK Signaling Pathway in Human Mesangial Cells.

C-type natriuretic peptide (CNP) is believed to be produced locally in the kidneys and possess several renoprotective properties. In contrast, fibroblast growth factor (FGF) -23 elevates in the early stage of chronic kidney disease and predicts its outcomes. Currently, several studies have demonstrated that CNP and FGF-23 act through a close pathway, and moreover, FGF-23/mitogen-activated protein kinase (MAPK) can be obviously suppressed by CNP. In the present study, human mesangial cells (MCs) were incubated in serum-containing medium in the absence or presence of CNP (0, 10 and 100 pM) for 24, 48 and 72 h, respectively. CNP administration significantly suppresses MCs proliferation in a time- and dose-dependent manner. As a down-stream signaling of CNP activation, the expressions of natriuretic peptide receptor (NPR)-B, cyclic guanosine monophosphate-dependent protein kinases II and NPR-C were obviously augmented, whereas neutral endopeptidase expression was significantly decreased after CNP treatment in MCs. FGF-23, FGF receptor-1 and RAF-1 experienced a pronounced down-regulation in MCs with different doses of CNP throughout the whole observational period. CNP may dampen FGF-23 expression via MAPK signaling pathway in MCs.