Advanced glycosylation end products inhibit the proliferation of bone-marrow stromal cells through activating MAPK pathway.

BACKGROUND: The purpose of present study was to explore the mechanism of nuclear factor-kappa B (NF-κB), phosphatidylinositol 3-kinase (PI3K)/protein kinase B(PKB/Akt) and mitogen-activated protein kinase (MAPK) signaling pathways after intervention of advanced glycosylation end products (AGEs) on rat bone-marrow stromal cells (BMSCs). METHODS: Prepare and identify AGEs. BMSCs were isolated from 16 SD rats and cultured with different concentration of AGEs. Cell viability was detected by cell counting kit-8 (CCK-8). BMSCs were cultured with AGEs (0.25 mg/ml) for 30 min, 12 h, 24 h, 72 h and 120 h. In addition, BMSCs were cultured with AGEs, AGEs + JNK inhibitor and AGEs + P38 inhibitor for 24 h and 48 h, respectively. Western blotting and RT-PCR were used to determine the protein and mRNA expression levels, respectively. RESULTS: Cell viability of BMSCs was significantly correlated with concentration and effect time of AGEs (P < 0.05), and the most appropriate concentration was 0.25 mg/ml. AGEs stimulation significantly increased the protein expression levels of NF-κB p65, JNK, p38 (P < 0.05), decreased IκB (P < 0.05), but had no effect on the protein expression of Akt in BMSCs (P > 0.05). At the mRNA level, JNK and p38 inhibitors significantly reduced the levels of NF-κB p65, p38 and JNK, increased IκB (P > 0.05), but had no effect on Akt in BMSCs (P > 0.05). At the protein level, JNK and p38 inhibitors notably decreased the expression of NF-κB p65, p38, p-JNK, P-IκB and JNK (P < 0.001), and increased IκB (P < 0.05). CONCLUSION: Advanced glycosylation end products can inhibit the proliferation of bone-marrow stromal cells through activating MAPK pathway.

Intestinal microbiota changes in Graves' disease: a prospective clinical study.

Graves' disease (GD) occurs due to an autoimmune dysfunction of thyroid gland cells, leading to manifestations consistent with hyperthyroidism. Various studies have confirmed the link between autoimmune conditions and changes in the composition of intestinal microbial organisms. However, few studies have assessed the relationship between the GD and the changes in intestinal microbiota. Therefore, the present study aimed to investigate changes in intestinal flora that may occur in the setting of GD. Thirty-nine patients with GD and 17 healthy controls were enrolled for fecal sample collection. 16S rRNA sequencing was used to analyze the diversity and composition of the intestinal microbiota. High-throughput sequencing of 16S rRNA genes of intestinal flora was performed on Illumina Hiseq2500 platform. Comparing to healthy individuals, the number of Bacilli, Lactobacillales, Prevotella, Megamonas and Veillonella strains were increased, whereas the number of Ruminococcus, Rikenellaceae and Alistipes strains were decreased among patients with GD. Furthermore, patients with GD showed a decrease in intestinal microbial diversity. Therefore, it indicates that the diversity of microbial strains is significantly reduced in GD patients, and patients with GD will undergo significant changes in intestinal microbiota, by comparing the intestinal flora of GD and healthy controls. These conclusions are expected to provide a preliminary reference for further researches on the interaction mechanism between intestinal flora and GD.

Initiating Characteristics of Early-onset Type 2 Diabetes Mellitus in Chinese Patients.

BACKGROUND: Type 2 diabetes mellitus (T2DM) has traditionally been considered to affect mainly the elderly; however, the age at diagnosis has gradually reduced in recent years. Although the incidence of young-onset T2DM is increasing, it is still not fully clear the onset characteristics and risk factors of early-onset T2DM. The aim of this study was to describe the initiating characteristics of early-onset T2DM in Chinese patients and evaluate the risk factors for diabetes mellitus. METHODS: This cross-sectional controlled study was performed using a questionnaire survey method in outpatients of multiple centers in China. A total of 1545 patients with T2DM with an age at onset of <40 years were included, and the control group consisted of subjects aged <40 years with normal blood glucose level. RESULTS: In patients with young-onset T2DM, the mean age and initial hemoglobin 1Ac at diagnosis were 32.96 ± 5.40 years and 9.59 ± 2.71%, respectively. Most of the patients were obese, followed irregular diet pattern and sedentary lifestyle, had life or work pressure, and had a family history of diabetes mellitus. Compared with subjects with normal blood glucose level, logistic regression analysis showed that waist-to-hip ratio (odds ratio [OR] 446.99, 95% confidence interval [CI] 42.37-4714.87), family history of diabetes mellitus (OR 23.46, CI 14.47-38.03), dyslipidemia (OR 2.65, CI 1.54-4.56), diastolic blood pressure (OR 1.02, CI 1.00-1.04), and body mass index (OR 0.95, CI 0.92-0.99) are independent factors for early-onset T2DM. CONCLUSIONS: We observed that abdominal obesity, family history of diabetes mellitus, and medical history of hypertension and dyslipidemia are independent risk factors for early-onset T2DM. It is, therefore, necessary to apply early lifestyle intervention in young people with risk of diabetes mellitus.

Mutation analyses in pedigrees and sporadic cases of ethnic Han Chinese Kallmann syndrome patients.

Kallmann syndrome, a form of idiopathic hypogonadotropic hypogonadism, is characterized by developmental abnormalities of the reproductive system and abnormal olfaction. Despite association of certain genes with idiopathic hypogonadotropic hypogonadism, the genetic inheritance and expression are complex and incompletely known. In the present study, seven Kallmann syndrome pedigrees in an ethnic Han Chinese population were screened for genetic mutations. The exons and intron-exon boundaries of 19 idiopathic hypogonadotropic hypogonadism (idiopathic hypogonadotropic hypogonadism)-related genes in seven Chinese Kallmann syndrome pedigrees were sequenced. Detected mutations were also tested in 70 sporadic Kallmann syndrome cases and 200 Chinese healthy controls. In pedigrees 1, 2, and 7, the secondary sex characteristics were poorly developed and the patients' sense of smell was severely or completely lost. We detected a genetic mutation in five of the seven pedigrees: homozygous KAL1 p.R191ter (pedigree 1); homozygous KAL1 p.C13ter (pedigree 2; a novel mutation); heterozygous FGFR1 p.R250W (pedigree 3); and homozygous PROKR2 p.Y113H (pedigrees 4 and 5). No genetic change of the assayed genes was detected in pedigrees 6 and 7. Among the 70 sporadic cases, we detected one homozygous and one heterozygous PROKR2 p.Y113H mutation. This mutation was also detected heterozygously in 2/200 normal controls and its pathogenicity is likely questionable. The genetics and genotype-phenotype relationships in Kallmann syndrome are complicated. Classical monogenic inheritance does not explain the full range of genetic inheritance of Kallmann syndrome patients. Because of stochastic nature of genetic mutations, exome analyses of Kallmann syndrome patients may provide novel insights.

Efficacy and safety of avandamet or uptitrated metformin treatment in patients with type 2 diabetes inadequately controlled with metformin alone: a multicenter, randomized, controlled trial.

BACKGROUND: At present, China has listed the compound tablet containing a fixed dose of rosiglitazone and metformin, Avandamet, which may improve patient compliance. The aim of this study was to evaluate the efficacy and safety of Avandamet or uptitrated metformin treatment in patients with type 2 diabetes inadequately controlled with metformin alone. METHODS: This study was a 48-week, multicenter, randomized, open-labeled, active-controlled trial. Patients with inadequate glycaemic control (glycated hemoglobin [HbA1c] 7.5-9.5%) receiving a stable dose of metformin (≥1500 mg) were recruited from 21 centers in China (from 19 November, 2009 to 15 March, 2011). The primary objective was to compare the proportion of patients who reached the target of HbA1c ≤7% between Avandamet and metformin treatment. RESULTS: At week 48, 83.33% of patients reached the target of HbA1c ≤7% in Avandamet treatment and 70.00% in uptitrated metformin treatment, with significantly difference between groups. The target of HbA1c ≤6.5% was reached in 66.03% of patients in Avandamet treatment and 46.88% in uptitrated metformin treatment. The target of fasting plasma glucose (FPG) ≤6.1 mmol/L was reached in 26.97% of patients in Avandamet treatment and 19.33% in uptitrated metformin treatment. The target of FPG ≤7.0 mmol/L was reached in 63.16% of patients in Avandamet treatment and 43.33% in uptitrated metformin treatment. Fasting insulin decreased 3.24 ± 0.98 µU/ml from baseline in Avandamet treatment and 0.72 ± 1.10 µU/ml in uptitrated metformin treatment. Overall adverse event (AE) rates and serious AE rates were similar between groups. Hypoglycaemia occurred rarely in both groups. CONCLUSIONS: Compared with uptitrated metformin, Avandamet treatment provided significant improvements in key parameters of glycemic control and was generally well tolerated. REGISTRATION NUMBER: ChiCTR-TRC-13003776.

Potential roles of glucagon-like peptide-1-based therapies in treating non-alcoholic fatty liver disease.

Glucagon-like peptide-1 (GLP-1)-based therapies have demonstrated efficacy and safety in treating type 2 diabetes, which shares a similar pathophysiological mechanism with non-alcoholic fatty liver disease (NAFLD). Recent studies showed that glucose-induced GLP-1 secretion was decreased in patients with NAFLD and that the level of dipeptidyl peptidase-4, which inactivates intact GLP-1, was upregulated. Moreover, the expression of the GLP-1 receptor was downregulated in livers from patients with NAFLD, indicating an association of defective GLP-1 signalling with NAFLD. Notably, GLP-1-based therapies are reported to be effective in improving hepatic endpoints in patients with NAFLD, such as reducing hepatic fat content, hepatic steatosis and plasma transaminase levels, and preventing fibrosis. GLP-1-based therapies are beneficial for body weight control and glycaemic normalisation, which are important for the management of NAFLD. Moreover, clinical and preclinical studies showed that GLP-1-based agents might directly exert their actions on the liver through activation of functional GLP-1 receptors in hepatocytes. The possible mechanisms involve regulating gene expression that is associated with insulin resistance and lipid metabolism, and suppressing oxidative stress in the liver cells, thus preventing the development and progression of NAFLD. Based on these promising data, large-scale randomised controlled trials are warranted to assess the efficacy and safety of GLP-1-based therapies in treating NAFLD.

High-fat diet induces early-onset diabetes in heterozygous Pax6 mutant mice.

BACKGROUND: Type 2 diabetes is caused by interactions between genetic and environmental factors. Our previous studies reported that paired box 6 mutation heterozygosity (Pax6(m/+)) led to defective proinsulin processing and subsequent abnormal glucose metabolism in mice at 6 months of age. However, high-fat diet exposure could be an important incentive for diabetes development. In this study, we aimed to develop a novel diabetic model imitating human type 2 diabetes by exposing Pax6(m/+) mice to high-fat diet and to explore the underlying mechanism of diabetes in this model. METHODS: Over 300 Pax6(m/+) and wild-type male weanling mice were randomly divided into two groups and were fed an high-fat diet or chow diet for 6-10 weeks. Blood glucose and glucose tolerance levels were monitored during this period. Body weights, visceral adipose weights, blood lipid profiles and insulin sensitivity (determined with an insulin tolerance test) were used to evaluate obesity and insulin resistance. Proinsulin processing and insulin secretion levels were used to evaluate pancreatic ß cell function. RESULTS: After 6 weeks of high-fat diet exposure, only the Pax6(m/+) mice showed dramatic postloading hyperglycaemia. These mice exhibited significant high-fat diet-induced visceral obesity and insulin resistance and displayed defective prohormone convertase 1/3 production, an increased proinsulin:total insulin ratio and impaired early-phase insulin secretion, because of the Pax6 mutation. Hyperglycaemia worsened progressively over time with the high-fat diet, and most Pax6(m/+) mice on high-fat diet developed diabetes or impaired glucose tolerance after 10 weeks. Furthermore, high-fat diet withdrawal partly improved blood glucose levels in the diabetic mice. CONCLUSIONS: By combining the Pax6(m/+) genetic background with an high-fat diet environment, we developed a novel diabetic model to mimic human type 2 diabetes. This model is characterized by impaired insulin secretion, caused by the Pax6 mutation, and high-fat diet-induced insulin resistance and therefore provides an ideal tool for research on type 2 diabetes pathogenesis and therapies.

The effects of pioglitazone on biochemical markers of bone turnover in the patients with type 2 diabetes.

Aim. To investigate whether pioglitazone had detrimental effects on biochemical markers of bone turnover in patients with type 2 diabetes (T2DM). Methods. Seventy patients with T2DM were included in this study. The patients remained on their previous antihyperglycemic therapies during the trial. Pioglitazone was then added on their regimen for 3 months. Results. After 3 months of treatment with pioglitazone, the levels of fasting blood glucose and HbA1c were significantly decreased (7.9 ± 1.5 mmol/L versus 9.1 ± 1.6 mmol/L and 7.1 ± 1.0% versus 8.2 ± 1.4%, resp., P < 0.01), compared with baseline in the overall patients. Serum concentrations of P1NP and BAP were significantly decreased from baseline (45.0 ± 20.0 µ g/L versus 40.6 ± 17.9 µ g/L and 13.23 ± 4.7 µ g/L versus 12.3 ± 5.0 µ g/L, resp., P < 0.01) in female group, but not in male group. The serum levels of OC and CTX were unchanged in both female and male subgroups. In addition, the levels of serum BAP and P1NP were significantly decreased after pioglitazone treatment in postmenopausal subgroup, comparing with baseline. Conclusion. Pioglitazone inhibits bone formation and does not seem to affect bone resorption. Postmenopausal female patients rather than premenopausal or male patients are particularly vulnerable to this side effect of pioglitazone.

[Serum level of programmed cell death 5 protein levels in patients with sepsis].

OBJECTIVE: To investigate the changes of serum programmed cell death 5 (PDCD5) levels in patients with critical illnesses including systemic inflammatory response syndrome (SIRS, except sepsis), sepsis (except severe sepsis) and severe sepsis. METHODS: A total of 78 patients were enrolled in this study, of whom, 28 were with SIRS, 23 with sepsis and 27 with severe sepsis. Twenty-two healthy individuals were included as controls. The levels of serum PDCD5 were evaluated by enzyme-linked immune sorbent assay. And the correlation analyses were made in the levels of sreum PDCD5 and acute physiology and chronic health evaluation II(APACHE II), high-sensitivity C-reactive protein(hs-CRP), white blood cell count, neutrophil count and age factors. RESULTS: Serum PDCD5 levels in the SIRS, sepsis and severe sepsis groups were (19.07 ± 8.91), (29.03 ± 13.27) and (42.83 ± 17.32) µg/L respectively, which were significantly higher than that in the healthy control group (0.32 ± 0.02) µg/L. Serum PDCD5 levels in SIRS, sepsis and severe sepsis groups were gradually increased with significant difference at any in-between comparison (P<0.05). Moreover, serum PDCD5 levels were positively correlated with the acute physiology and chronic health evaluation II (APACHE II) score (r=0.572, P<0.05). CONCLUSION: The serum PDCD5 levels in the critically ill patients with sepsis were progressively increased with the worsened condition. The up-regulated expression of PDCD5 may play an important role in the development and progression of sepsis.

Dynamic expression of microRNAs during the differentiation of human embryonic stem cells into insulin-producing cells.

Human embryonic stem (hES) cells with the capacity of self-renewal and multilineage differentiation are promising sources for generation of pancreatic islet cells for cell replacement therapy in diabetes. Here we induced hES cells into insulin-producing cells (IPCs) in a stepwise process which recapitulated islet organogenesis by directing cells through the stages resembling definitive endoderm, gut-tube endoderm, pancreatic precursor and cells that expressed pancreatic endocrine hormones. The dynamic expression of microRNAs (miRNAs) during the differentiation was analyzed and was compared with that in the development of human pancreatic islets. We found that the dynamic expression patterns of miR-375 and miR-7 were similar to those seen in the development of human fetal pancreas, whereas the dynamic expression of miR-146a and miR-34a showed specific patterns during the differentiation. Furthermore, the expression of Hnf1ß and Pax6, the predicted target genes of miR-375 and miR-7, was reciprocal to that of miR-375 and miR-7. Over-expression of miR-375 down-regulated the expression of gut-endoderm/pancreatic progenitor specific markers Hnf1ß and Sox9. Therefore, the miRNAs may directly or indirectly regulate the expression of pancreatic islet organogenesis-specific transcription factors to control the differentiation and maturation of pancreatic islet cells.

Improving presurgical pupil dilation for cataract surgery patients.

Insufficient pupil dilation, a common challenge in cataract surgery, may lead to surgical complications. After a quality improvement project was conducted, the proportion of patients with the desired pupil dilation of > or = 7 mm increased from 39.5% to 88.0% (Implementation phase) and then to 82.2% (Sustaining phase).

[Correlation of large artery stiffness and coronary flow velocity reserve].

OBJECTIVE: Coronary flow velocity reserve (CFVR) is an important indicator of coronary endothelial functions and microcirculation. Pulse wave velocity (PWV) reflects the degree of aortic sclerosis and it is an independent predictor of cardiovascular events. The present study was designed to evaluate the correlation of large artery stiffness and CFVR. METHODS: A total of 101 consecutive subjects were enrolled to measure the brachial-ankle pulse wave velocity (baPWV). According to the presence or absence of higher baPWV (> 1400 cm/s), they were divided into 2 groups. Transthoracic echocardiography was employed to measure coronary flow velocity in coronary left anterior descending (LAD). Then after an intravenous infusion of adenosine triphosphate, the velocity of blood flow was measured when the vessel was in maximal dilation. The ratio of flow velocity of those in maximal dilation to those at rest was CFVR. RESULTS: The subjects with a higher baPWV (> 1400 cm/s) were markedly elder and had higher risks of hypertension and diabetes. Thus age, hypertension and diabetes contributed to arteriosclerosis. More importantly, the subjects with a higher baPWV (> 1400 cm/s) had a much lower level of CFVR (2.66 ± 0.74 vs 2.95 ± 0.76; P < 0.01) than those with a lower baPWV (< 1400 cm/s). Furthermore correlation analysis showed that CFVR and baPWV levels were significantly negatively correlated (r = -0.35, P < 0.01). CONCLUSIONS: A negative correlation exists between artery stiffness and coronary flow velocity reserve. The increased vascular stiffness may impair coronary endothelial function, cause the dysfunction of coronary microcirculation and raise the risks of cardiovascular events.

Ghrelin promotes differentiation of human embryonic stem cells into cardiomyocytes.

AIM: Ghrelin is involved in regulating the differentiation of mesoderm-derived precursor cells. The aim of this study was to investigate whether ghrelin modulated the differentiation of human embryonic stem (hES) cells into cardiomyocytes and, if so, whether the effect was mediated by growth hormone secretagogue receptor 1α (GHS-R1α). METHODS: Cardiomyocyte differentiation from hES cells was performed according to an embryoid body (EB)-based protocol. The cumulative percentage of beating EBs was calculated. The expression of cardiac-specific markers including cardiac troponin I (cTnI) and α-myosin heavy chain (α-MHC) was detected using RT-PCR, real-time PCR and Western blot. The dispersed beating EBs were examined using immunofluorescent staining. RESULTS: The percentage of beating EBs and the expression of cTnI were significantly increased after ghrelin (0.1 and 1 nmol/L) added into the differentiation medium. From 6 to 18 d of differentiation, the increased expression of cTnI and α-MHC by ghrelin (1 nmol/L) was time-dependent, and in line with the alteration of the percentages of beating EBs. Furthermore, the dispersed beating EBs were double-positively immunostained with antibodies against cTnI and α-actinin. However, blockage of GHS-R1α with its specific antagonist D-[lys(3)]-GHRP-6 (1 µmol/L) did not alter the effects of ghrelin on cardiomyocyte differentiation. CONCLUSION: Our data show that ghrelin enhances the generation of cardiomyocytes from hES cells, which is not mediated via GHS-R1α.

[Therapeutic cloning and somatic cell reprogramming: every road leads to Rome].

The researches of therapeutic cloning and somatic cell reprogramming, two strategies used to generate patient-specific autologous stem cells, have recently made great progress. Therapeutic cloning refers to derivation of embryonic stem cells from blastocyst produced by somatic cell nuclear transfer, whereas somatic cell reprogramming refers to establishment of induced pluripotent stem (iPS) cells from differentiated somatic cells by ectopic expression of specific transcription factors. The two strategies differ in their methodological approaches, technical obstacles and ethical debates, but confront similar problems including the differentiation of stem cells and the feasibility of cell-replacement therapy. This review discusses the research advance of these two biotechnologies and summarizes their difference and similarity.

Inhibition of hepatic interleukin-18 production by rosiglitazone in a rat model of nonalcoholic fatty liver disease.

AIM: To investigate the effects of rosiglitazone (RGZ) on expression of interleukin-18 (IL-18) and caspase-1 in liver of non-alcoholic fatty liver disease (NAFLD) rats. METHODS: Twenty-eight Sprague-Dawley (SD) rats were randomly divided into control, NAFLD, and RGZ treated NAFLD groups. A NAFLD rat model of NAFLD was established by feeding the animals with a high-fat diet for 12 wk. The NAFLD animals were treated with RGZ or vehicle for the last 4 wk (week 9-12) and then sacrificed to obtain liver tissues. Histological changes were analyzed with HE, oil red O and Masson's trichrome staining. Expressions of IL-18 and caspase-1 were detected using immunohistochemical staining and semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) analysis. RESULTS: The expression levels of both IL-18 and caspase-1 were higher in the liver of NAFLD group than in the control group. Steatosis, inflammation and fibrosis, found in the liver of NAFLD rats, were significantly improved 4 wk after RGZ treatment. The elevated hepatic IL-18 and caspase-1 expressions in NAFLD group were also significantly attenuated after RGZ treatment. CONCLUSION: RGZ treatment can ameliorate increased hepatic IL-18 production and histological changes in liver of NAFLD rats. The beneficial effects of RGZ on NAFLD may be partly due to its inhibitory effect on hepatic IL-18 production.

[Thyrocytes contribute to their own demise: the role of interleukin-18 in Hashimoto's thyroiditis].

OBJECTIVE: To investigate the IL-18 expression in the thyroid tissues of Hashimoto's thyroiditis (HT) and its cellular localization and the effect of interferon-gamma (IFN-gamma) on the interleukin- (IL)-18 expression in thyrocytes. METHODS: RT-PCR and immunohistochemistry were used to detect the IL-18 expression and its cellular localization in the thyroid tissues biopsy specimens of 6 HT patients with normal thyroid function, 6 normal thyroid specimens resected from patients with pharyngeal carcinoma, and 16 specimens of thyroid tissues adjacent to the thyroid adenoma obtained during operation. Thyrocytes were isolated, cultured, and exposed to IL-1beta, tumor necrosis factor-alpha (TNF-alpha), or IFN-gamma for 48 h. RT-PCR and Western blotting were used to detect the IL-18 expression. RESULTS: IL-18 mRNA expression was at an extremely low levels in the normal thyroid tissues and at a significantly higher level in the thyroid tissues of HT. Immunohistochemical staining showed that IL-18 expression was augmented in the thyroid tissues of HT and was mainly localized in the thyroid follicular cells. The IL-18 mRNA expression in the isolated human thyrocytes was dose-dependently elevated by IFN-gamma rather than TNF-alpha or IL-1beta. Western blotting showed that pro-IL-18, but not mature IL-18, was detected in the lysates of the cultured human thyrocytes and the expression of pro-IL-18 was increased by IFN-gamma. CONCLUSION: IL-18 expression is elevated in the thyroid follicular cells of HT. IL-18 is constitutively expressed in the isolated human thyrocytes and its expression is up-regulated by IFN-gamma. Therefore, interplay between IL-18 and IFN-gamma may have an important role in the thyrocytes destruction in HT.

[Diagnosis and treatment of 17 alpha-hydroxylase deficiency: a case report and literature review].

A 16-year-old "female" patient presented as hypertension, hypokalemia, male pseudohermaphroditism, lowered gonadal steroids and cortisol, elevated adrenocorticotropic hormone and pituitary gonadotropin, and 46 XY karyotype. The patient was diagnosed as 17 alpha-hydroxylase deficiency, a rare case of congenital adrenal hyperplasia. "She" chose to remain female appearance and social gender after negotiation with the parents. Cryptor-chidism of both inguinal canals was surgically removed for preventing canceration. After the surgery, a very small daily dose of dexamethasone (0.187 5 mg at bedtime) was enough to control hypertension and hypokalemia, and the therapy of conjugated estrogens (Premarin) was given to promote the development of female characters. After 6 months of treatment, normotension and normokalemia remained, and pubarche and mammogenesis emerged.