Plasma miR-193b-3p Is Elevated in Type 2 Diabetes and Could Impair Glucose Metabolism.

Objective: To explore differentially expressed miRNAs in type 2 diabetes and their potential cellular functions. Methods: We screened plasma miRNAs by miRNA array analysis and validated them by TaqMan real-time PCR in 113 newly diagnosed, untreated type 2 diabetes cases and 113 healthy controls. Low-abundance plasma proteins encoded by miR-193b-3p target genes were explored in this study population. We further investigated the potential cellular functions of the differentially expressed miRNAs in HepG2 cells. Results: miR-193b-3p was differentially expressed in type 2 diabetes cases compared to healthy controls (fold change = 2.01, P = 0.006). Plasma levels of triosephosphate isomerase (TPI1, a protein involved in the glycolytic pathway) decreased in type 2 diabetes cases (fold change = 1.37, P = 0.002). The effect of miR-193b-3p on TPI1 was verified by transfection of miR-193b-3p into HepG2 cells. miR-193b-3p inhibited the expression of YWHAZ/14-3-3ζ in the PI3K-AKT pathway, subsequently altering the expression of FOXO1 and PCK1. After transfection, cells were incubated in glucose-free medium for another 4 h. Glucose levels in medium from cells with elevated miR-193b-3p levels were significantly higher than those in medium from negative control cells (P = 0.016). In addition, elevated miR-193b-3p reduced glucose uptake by inhibiting insulin receptor (IR) and GLUT2 expression. Conclusion: Plasma miR-193b-3p levels increased in type 2 diabetes cases, and TPI1 levels decreased in both plasma and HepG2 cells with increased miR-193b-3p levels, while extracellular lactate levels did not significantly changed. Moreover, miR-193b-3p may affect glucose metabolism by directly targeting YWHAZ/14-3-3ζ and upregulating the transcription factor FOXO1 downstream of the PI3K-AKT pathway.

Associations of plasma metal levels with type 2 diabetes and the mediating effects of microRNAs.

The present study aims to determine the associations of multiple plasma metal levels and plasma microRNAs (miRNAs) with diabetes risk, and further explore the mediating effects of plasma miRNAs on the associations of plasma metal with diabetes risk. We detected plasma levels of 23 metals by inductively coupled plasma mass spectrometry (ICP-MS) among 94 newly diagnosed and untreated diabetic cases and 94 healthy controls. The plasma miRNAs were examined by microRNA Array screening and Taqman real-time PCR validation among the same study population. The multivariate logistic regression models were employed to explore the associations of plasma metal and miRNAs levels with diabetes risk. Generalized linear regression models were utilized to investigate the relationships between plasma metal and plasma miRNAs, and mediation analysis was used to assess the mediating effects of plasma miRNAs on the relationships between plasma metals and diabetes risk. Plasma aluminum (Al), titanium (Ti), copper (Cu), zinc (Zn), selenium (Se), rubidium (Rb), strontium (Sr), barium (Ba), and Thallium (Tl) levels were correlated with elevated diabetic risk while molybdenum (Mo) with decreased diabetic risk (P < 0.05 after FDR multiple correction). MiR-122-5p and miR-3141 were positively associated with diabetes risk (all P < 0.05). Ti, Cu, and Zn were positively correlated with miR-122-5p (P = 0.001, 0.028 and 0.004 respectively). Ti, Cu, and Se were positively correlated with miR-3141 (P = 0.003, 0.015, and 0.031 respectively). In addition, Zn was positively correlated with miR-193b-3p (P = 0.002). Ti was negatively correlated with miR-26b-3p (P = 0.016), while Mo and miR-26b-3p were positively correlated (P = 0.042). In the mediation analysis, miR-122-5p mediated 48.0% of the association between Ti and diabetes risk. The biological mechanisms of the association are needed to be explored in further studies.

Association of blood pressure and long-term change with chronic kidney disease risk among Chinese adults with different glucose metabolism according to the 2017 ACC/AHA guidelines.

Whether the definition of hypertension according to 2017 AHA/ACC guidelines and blood pressure (BP) changes was related to the increased risk of chronic kidney disease (CKD) remained debated. This prospective cohort study aimed to investigate the association of BP and long-term BP change with CKD risk with different glucose metabolism according to the new hypertension guidelines. This study examined 12 951 participants and 11 183 participants derived from the older people cohort study, respectively. Participants were divided into three groups based on blood glucose and the risks were assessmented by the logistic regression model. During a 10 years of follow-up period, 2727 individuals developed CKD (21.1%). Compared with those with BP < 130/80 mmHg, individuals with increased BP levels had significantly increased risk of incident CKD. Participants with BP of 130-139/80-89 or ≥140/90 mmHg had 1.51- and 1.89-fold incident risk of CKD in patients with diabetes mellitus (DM). Compared with individuals with stable BP (-5 to 5 mmHg), the risk of CKD was reduced when BP decreased by 5 mmHg or more and increased when BP increased ≥5 mmHg among normoglycemia and prediabetes participants. Similar results were observed for rapid estimated glomerular filtration rate (eGFR) decline. In conclusion, the BP of 130-139/80-89 mmHg combined with prediabetes or DM had an increased risk of incident CKD and rapid eGFR decline in older people. Long-term changes of BP by more than 5 mmHg among normoglycemia or prediabetes were associated with the risk of incident CKD and rapid eGFR decline.

Associations of serum bisphenol A levels with incident chronic kidney disease risk.

Associations of bisphenol A (BPA) levels with renal disease are inconsistent. The present prospective study aims to evaluate the association of serum BPA levels with chronic kidney disease (CKD) in a Chinese middle-aged and elderly population. At baseline 1370 participants (mean age 61.7 years, 58.8% females) free of kidney disease and cancer were followed up nearly 10 years. Baseline serum BPA concentration was measured with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS). Estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Multivariable logistic regression model was used to investigate relationship between serum BPA levels and incident CKD risk. During a 10-year follow-up, 246 individuals developed CKD. Baseline serum BPA concentration was 2.92 (1.00, 5.27) ng/mL. At baseline, after adjustment for multiple covariates serum BPA levels were negatively correlated with eGFR levels (ß = -0.068, P = 0.009). Compared to those with low levels of serum BPA, participants with high levels had a significant negative association with CKD [ORs (95% CI) = 0.35 (0.25, 0.50), P < 0.001], and this association was not modified by conventional risk factors. The negative associations remained in females but not in males (P for interaction = 0.016). Significant interaction between baseline eGFR and serum BPA levels on CKD risk was also found (P for interaction = 0.027), Except subjects with 60-70 mL/min/1.73 m2 eGFR at baseline, inverse association robustly existed between serum BPA levels and incident CKD risk in the other eGFR subgroups. Further studies are needed to validate our findings.

DC-Analyzer-facilitated combinatorial strategy for rapid directed evolution of functional enzymes with multiple mutagenesis sites.

Iterative saturation mutagenesis (ISM) has been shown to be a powerful method for directed evolution. In this study, the approach was modified (termed M-ISM) by combining the single-site saturation mutagenesis method with a DC-Analyzer-facilitated combinatorial strategy, aiming to evolve novel biocatalysts efficiently in the case where multiple sites are targeted simultaneously. Initially, all target sites were explored individually by constructing single-site saturation mutagenesis libraries. Next, the top two to four variants in each library were selected and combined using the DC-Analyzer-facilitated combinatorial strategy. In addition to site-saturation mutagenesis, iterative saturation mutagenesis also needed to be performed. The advantages of M-ISM over ISM were that the screening effort is greatly reduced, and the entire M-ISM procedure was less time-consuming. The M-ISM strategy was successfully applied to the randomization of halohydrin dehalogenase from Agrobacterium radiobacter AD1 (HheC) when five interesting sites were targeted simultaneously. After screening 900 clones in total, six positive mutants were obtained. These mutants exhibited 4.0- to 9.3-fold higher k(cat) values than did the wild-type HheC toward 1,3-dichloro-2-propanol. However, with the ISM strategy, the best hit showed a 5.9-fold higher k(cat) value toward 1,3-DCP than the wild-type HheC, which was obtained after screening 4000 clones from four rounds of mutagenesis. Therefore, M-ISM could serve as a simple and efficient version of ISM for the randomization of target genes with multiple positions of interest.