Sclerotome-derived PDGF signaling functions as a niche cue responsible for primitive erythropoiesis.

Primitive erythropoiesis serves a vital role in embryonic development, generating primitive red blood cells responsible for transportation of oxygen throughout the body. Although diverse niche factors are known to function in definitive hematopoiesis, the microenvironment contributing to primitive hematopoiesis remains largely elusive. Here, we report that platelet-derived growth factor (PDGF) signaling is required for erythroid progenitor differentiation in zebrafish. Ablating pdgfαa (also known as pdgfaa) and pdgfαb (also known as pdgfab) or blocking PDGF signaling with an inhibitor impairs erythroid progenitor differentiation, thus resulting in a significant decrease in the number of erythrocytes. We reveal that pdgfαb is expressed in sclerotomal cells, and that its receptor genes, pdgfra and pdgfrb, are expressed in the adjacent erythroid progenitor cells. Sclerotome-specific overexpression of pdgfαb effectively restores primitive erythropoiesis in pdgfαa-/-;pdgfαb-/- mutant embryos. In addition, we have defined ERK1/2 signaling as a downstream pathway of PDGF signaling during embryonic erythropoiesis. Taken together, our findings indicate that PDGF signaling derived from sclerotome functions as a niche cue for primitive erythropoiesis.

Measurement of cumulative high-sensitivity C-reactive protein and monocyte to high-density lipoprotein ratio in the risk prediction of type 2 diabetes: a prospective cohort study.

BACKGROUND: Converging data have suggested that monocytic inflammation and C-reactive protein (CRP) are biologically intertwined processes and are involved in diabetogenesis. This study aimed to investigate the association between systemic inflammation assessed by joint cumulative high-sensitivity C-reactive protein (CumCRP) and monocyte to high-density lipoprotein ratio (CumMHR) and incident type 2 diabetes (T2D) and their predictive value for T2D in a general population. METHODS: A total of 40,813 nondiabetic participants from a prospective real-life cohort (Kailuan Study, China) were followed biennially from 2010/2011 until December 31, 2020. Multivariable Cox regression analyses were conducted to evaluate the adjusted hazard ratios (aHRs) of incident diabetes. RESULTS: During a median follow-up of 7.98 (IQR: 5.74-8.87) years, 4848 T2D cases developed. CumMHR and CumCRP were alone or jointly associated with incident T2D after adjusting for potential confounders. Elevated CumMHR levels significantly increased the risk of incident diabetes in each CumCRP strata (P-interaction: 0.0278). Participants with concomitant elevations in CumMHR and CumCRP levels had the highest risk (aHR: 1.71, 95% CI 1.52-1.91) compared to both in the low strata. Notably, the coexposure-associated T2D risk was modified by age, sex, hypertension, dyslipidemia, and prediabetes status. C-statistics increased from 0.7377 to 0.7417 when CumMHR and CumCRP were added into the multivariable-adjusted model, with a net reclassification improvement (%) of 12.39 (9.39-15.37) (P < 0.0001). CONCLUSIONS: Cumulative hsCRP and MHR were both independently and jointly associated with an increased risk of T2D and their addition to established risk factors should improve risk prediction and reclassification of diabetes.

The association of uric acid with the development of thyroid nodules: a retrospective cohort study.

BACKGROUND: Uric acid was found to have a positive correlation with thyroid nodules in the cross-sectional studies recently. We aimed to conduct a retrospective cohort study to investigate whether uric acid is a risk factor for the development of thyroid nodules. METHODS: We reviewed the data of individuals who attended the medical check-ups in our hospital from 2010 to 2019. A total of 6587 adults without thyroid nodules at baseline were enrolled in this study. Logistic regression with or without restricted cubic spline function was used to investigate the non-linear or linear association between uric acid and thyroid nodules, respectively. RESULTS: Baseline characteristics showed that subjects mainly consisted of the healthy, young population. After fully adjusting for the potential confounders, such as age, sex, metabolic and inflammatory indicators, hepatic and renal function, a logistic restricted cubic spline regression model suggested that uric acid had a significant association (P = 0.028) with the development of thyroid nodules, but the association was not non-linear (P = 0.516). The results indicate that the association between them is linear, which was demonstrated by a logistic regression model, in which the odds ratio of uric acid per 100 mmol/L was 1.137 (P = 0.004). Age, sex, diastolic blood pressure, fasting blood sugar, and blood monocyte were found to be risk factors for thyroid nodules as well. CONCLUSION: Uric acid is an independent risk factor for the formation of thyroid nodules. This finding warrants attention to this risk factor in apparently healthy adults.

Effectiveness and safety of human amnion/chorion membrane therapy for diabetic foot ulcers: An updated meta-analysis of randomized clinical trials.

Human amnion/chorion membrane therapy has shown advantages in the management of diabetic foot ulcers and its effectiveness has been evaluated in the systematic reviews and meta-analyses. However, the number of patients included in the previous literatures was small and the safety profile of human amnion/chorion membrane therapy was not concerned. Therefore, we conducted an updated meta-analysis to better understand the effectiveness and safety of human amnion/chorion membrane therapy for diabetic foot ulcers. The PubMed, Embase, Cochrane Library, and ClinicalTrial.gov databases were searched for any randomized clinical trials comparing human amnion/chorion membrane therapy and standard therapy in the treatment of diabetic foot ulcers. Ulcer healing rate was considered as the primary outcome and the secondary outcomes mainly included mean time to ulcer healing and adverse events. Nine RCTs with 541 patients were included. Compared with merely standard therapy, human amnion/chorion membrane therapy plus standard therapy improved the ulcer healing rates at 6 weeks (RR = 3.50, 95% CI: 2.35-5.21), 12 weeks (RR = 2.09, 95% CI: 1.53-2.85) and 16 weeks (RR = 1.70, 95% CI: 1.25-2.30), and also shortened the healing time (MD = -4.58, 95% CI: -5.70 to -3.46). Meanwhile, no significant difference was observed in the number of patients with adverse events (RR = 0.56, 95% CI: 0.31-1.03) between two groups. This meta-analysis suggests that human amnion/chorion membrane therapy as an adjuvant treatment could promote the healing of diabetic foot ulcers and has a safety profile. More evidence from large high-quality randomized clinical trials with long follow-up duration are in urgent need to further confirm our findings.

Targeted deletion of Insm2 in mice result in reduced insulin secretion and glucose intolerance.

BACKGROUND: Neurogenin3 (Ngn3) and neurogenic differentiation 1 (NeuroD1), two crucial transcriptional factors involved in human diabetes (OMIM: 601724) and islet development, have been previously found to directly target to the E-boxes of the insulinoma-associated 2 (Insm2) gene promoter, thereby activating the expression of Insm2 in insulin-secretion cells. However, little is known about the function of Insm2 in pancreatic islets and glucose metabolisms. METHODS: Homozygous Insm2-/- mice were generated by using the CRISPR-Cas9 method. Glucose-stimulated insulin secretion and islet morphology were analyzed by ELISA and immunostainings. Expression levels of Insm2-associated molecules were measured using quantitative RT-PCR and Western blots. RESULTS: Fasting blood glucose levels of Insm2-/- mice were higher than wild-type counterparts. Insm2-/- mice also showed reduction in glucose tolerance and insulin/C-peptide levels when compared to the wild-type mice. RT-PCR and Western blot analysis revealed that expression of Insm1 was significantly increased in Insm2-/- mice, suggesting a compensatory response of the homolog gene Insm1. Similarly, transcriptional levels of Ngn3 and NeuroD1 were also increased in Insm2-/- mice. Moreover, Insm2-/- female mice showed a significantly decreased reproductive capacity. CONCLUSIONS: Our findings suggest that Insm2 is important in glucose-stimulated insulin secretion and is involved in the development pathway of neuroendocrine tissues which are regulated by the transcription factors Ngn3, NeuroD1 and Insm1.

Incorporation of VSV-G produces fusogenic plasma membrane vesicles capable of efficient transfer of bioactive macromolecules and mitochondria.

The objective of this study was to determine if plasma membrane vesicles (PMVs) could be exploited for efficient transfer of macro-biomolecules and mitochondria. PMVs were derived from mechanical extrusion, and made fusogenic (fPMVs) by incorporating the glycoprotein G of vesicular stomatitis virus (VSV-G). Confocal microscopy examination revealed that cytoplasmic proteins and mitochondria were enclosed in PMVs as evidenced by tracing with cytoplasmically localized and mitochondria-targeted EGFP, respectively. However, no fluorescence signal was detected in PMVs from cells whose nucleus was labeled with an EGFP-tagged histone H2B. Consistently, qRT-PCR measurement showed that mRNA, miRNA and mitochondrial DNA decreased slightly; while nuclear DNA was not measureable. Further, Western blot analysis revealed that cytoplasmic and membrane-bound proteins fell inconspicuously while nuclear proteins were barely detecsle. In addition, fPMVs carrying cytoplamic DsRed proteins transduced about ~40 % of recipient cells. The transfer of protein was further confirmed by using the inducible Cre/loxP system. Mitochondria transfer was found in about 20 % recipient cells after incubation with fPMVs for 5 h. To verify the functionalities of transferred mitochondria, mitochodria-deficient HeLa cells (Rho0) were generated and cultivated with fPMVs. Cell enumeration demonstrated that adding fPMVs into culture media stimulated Rho0 cell growth by 100 % as compared to the control. Lastly, MitoTracker and JC-1 staining showed that transferred mitochondria maintained normal shape and membrane potential in Rho0 cells. This study established a time-saving and efficient approach to delivering proteins and mitochondria by using fPMVs, which would be helpful for finding a cure to mitochondria-associated diseases. Graphical abstract Schematic of the delivery of macro-biomolecules and organelles by fPMVs. VSV-G-expressing cells were extruded through a 3 µm polycarbonate membrane filter to generate fusogenic plasma membrane vesicles (fPMVs), which contain bioactive molecules and organelles but not the nucleus. fPMVs can be endocytosed by target cells, while the cargo is released due to low-pH induced membrane fusion. These nucleus-free fPMVs are efficient at delivery of cytoplasmic proteins and mitochondria, leading to recovery of mitochondrial biogenesis and proliferative ability in mitochondria-deficient cells.

Niacin receptor GPR109A inhibits insulin secretion and is down-regulated in type 2 diabetic islet beta-cells.

OBJECTIVES: We previously found niacin receptor GPR109A was expressed in murine islet beta-cells, and signaling through GPR109A inhibited glucose stimulated insulin secretion (GSIS). However, the expression of GPR109A in human islets and its functional relevance is still not known. METHODS: The expression of GPR109A was examined by antibody staining and in situ hybridization on pancreatic paraffin sections. GPR109A was cloned and expressed in INS-1 islet beta-cells. Intracellular cAMP and GSIS were determined using enzyme-linked immunosorbent assay (ELISA). RESULTS: The expression of GPR109A was confirmed in murine islet beta-cells and further detected in human counterparts by using commercially available polyclonal antibodies. In situ hybridization study detected the transcripts of GPR109A, but not that of closely related GPR109B. Furthermore, GPR109A was significantly reduced in islets from diabetic individuals and animal model of db/db mice as compared to their respective controls. Further, GPR109A levels in insulinoma were also reduced dramatically as compared to islets found in corresponding non-tumor normal tissues. Quantitative RT-PCR analysis demonstrated that GPR109A transcripts were severely down-regulated in rodent insulinoma cell lines as compared to that of freshly isolated islets from mice. Finally, human and murine GPR109A expression cassettes were transfected into INS-1 cells, which resulted in reduced accumulation of cAMP and insulin secretion after incubation with niacin. The effect could be completely abrogated by pretreatment with pertussis toxin. CONCLUSIONS: These results demonstrate that GPR109A is functionally expressed in both human and murine islet beta-cells. However, the role of GPR109A in the prevention of diabetes or insulinoma needs further study.

Genetic insights into repurposing statins for hyperthyroidism prevention: a drug-target Mendelian randomization study.

Background: Current therapeutic measures for thyroid dysfunction are limited and often accompanied by adverse effects. The use of lipid-lowering drugs like statins has recently been associated with lower thyroid eye diseases risk. Objective: To investigate the implications of genetically proxied lipid-lowering drugs on thyroid dysfunction. Methods: In this drug-target Mendelian randomization (MR) study, we utilized genetic variants within drug target genes associated with low-density lipoprotein (LDL) or triglyceride (TG), derived from a genome-wide association study (GWAS) meta-analysis (N ≤ 188,577), to simulate lifelong drug interventions. Genetic summary statistics for thyroid dysfunction outcomes were retrieved from GWAS datasets of Thyroid Omics Consortium (N ≤ 54,288) and UK Biobank (N = 484,598). Inverse-variance-weighted MR (IVW-MR) method was performed as primary analysis, followed by validation in colocalization analysis. A subsequent two-step MR analysis was conducted to identify biomarkers mediating the identified drug-outcome association. Results: In IVW-MR analysis, genetic mimicry of 3-hydroxy-3-methylglutarylcoenzyme reductase (HMGCR) inhibitors (e.g. statins) was significantly associated with lower risk of hyperthyroidism in two independent datasets (OR1, 0.417 per 1-mmol/L lower in LDL-C; 95% CI 0.262 to 0.664; P1 = 2.262 × 10-4; OR2 0.996; 95% CI 0.993-0.998; P2 = 0.002). Two-step MR analysis revealed eighteen biomarkers linked to genetic mimicry of HMGCR inhibition, and identified insulin-like growth factor 1 (IGF-1) levels mediating 2.108% of the negative causal relationship between HMGCR inhibition and hyperthyroidism. Conclusion: This study supports HMGCR inhibition as a promising therapeutic strategy for hyperthyroidism and suggests its underlying mechanisms may extend beyond lipid metabolism. Further investigations through laboratory studies and clinical trials are necessary to confirm and elucidate these findings.

Rapid and Amplification-free Nucleic Acid Detection with DNA Substrate-Mediated Autocatalysis of CRISPR/Cas12a.

To enable rapid and accurate point-of-care DNA detection, we have developed a single-step, amplification-free nucleic acid detection platform, a DNA substrate-mediated autocatalysis of CRISPR/Cas12a (DSAC). DSAC makes use of the trans-cleavage activity of Cas12a and target template-activated DNA substrate for dual signal amplifications. DSAC employs two distinct DNA substrate types: one that enhances signal amplification and the other that negatively modulates fluorescent signals. The positive inducer utilizes nicked- or loop-based DNA substrates to activate CRISPR/Cas12a, initiating trans-cleavage activity in a positive feedback loop, ultimately amplifying the fluorescent signals. The negative modulator, which involves competitor-based DNA substrates, competes with the probes for trans-cleaving, resulting in a signal decline in the presence of target DNA. These DNA substrate-based DSAC systems were adapted to fluorescence-based and paper-based lateral flow strip detection platforms. Our DSAC system accurately detected African swine fever virus (ASFV) in swine's blood samples at femtomolar sensitivity within 20 min. In contrast to the existing amplification-free CRISPR/Dx platforms, DSAC offers a cost-effective and straightforward detection method, requiring only the addition of a rationally designed DNA oligonucleotide. Notably, a common ASFV sequence-encoded DNA substrate can be directly applied to detect human nucleic acids through a dual crRNA targeting system. Consequently, our single-step DSAC system presents an alternative point-of-care diagnostic tool for the sensitive, accurate, and timely diagnosis of viral infections with potential applicability to human disease detection.

Transient embolization with microspheres of polyhydroxyalkanoate renders efficient adenoviral transduction of pancreatic capillary in vivo.

BACKGROUND: Our previous study showed an efficient targeting of islets of Langerhans by adenoviral injection via the celiac trunk. Unexpectedly, none of the endothelial cells was infected given the direct contact between adenoviruses and the capillary wall. The present study intended to provide an efficient approach for adenoviral targeting of the microcapillary endothelial cells in the pancreas. METHODS: We prepared microspheres of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) with a size comparable to the diameter of capillary (5-10 µm). Scanning electron microscopy was applied to verify that adenoviruses carrying a green fluorescence protein gene were complexed with PHBHHx-microspheres after 30 min of co-incubation. The complexes were then injected into the pancreas of mice via the celiac trunk. RESULTS: Approximately 40% of endothelial cells in the pancreas were labeled 5 days after surgery. Islet cells were labeled occasionally, whereas labeling of the acinar and ductal tissues was barely detectable. Endothelium targeting was inefficient in other internal organs. Consistent with the reported superior tissue compatibility of PHBHHx, no discernable microspheres were found in all of the organs examined. Furthermore, splenocyte activation was dampened when adenoviruses were complexed with the microspheres. CONCLUSIONS: The present study has established an approach for efficient pancreatic capillary targeting by using microsphere-adenoviral complexes. This procedure could be invaluable for the treatment of capillary-related diseases.

Intra-arterial targeted islet-specific expression of Sirt1 protects ß cells from streptozotocin-induced apoptosis in mice.

Gene therapy provides a promising approach to curing diabetes. However, an effective route for islet-specific targeting has yet to be established. Toward this end, the pancreatic blood circulation system in Balb/c mice was determined by the injection of rhodamine-containing beads. The efficiency of islet targeting was then measured by the injection of adenoviral vectors carrying a green fluorescence gene via the celiac trunk (C.T.). The results showed that >95% of islets and about 60% of ß cells within the pancreatic body and tail could be labeled 3 days after surgery. α-Cell labeling was not as efficient, whereas labeling of nonendocrine tissues was barely detectable. For proof of principle, adenoviral vectors carrying a Sirtuin transgene were injected similarly to test the islet protection effect in the streptozotocin (STZ)-induced type 1 diabetic model. The results demonstrated that overexpression of Sirtuin in STZ-treated mice reduced the level of ß-cell death and extent of glucose intolerance. This study reports on efficient islet-specific targeting by using adenoviral injection. This procedure could be invaluable to the treatment of diabetes and the study of islet biology.

Membrane tethering of CreER decreases uninduced cell labeling and cytotoxicity while maintaining recombination efficiency.

Genetic lineage tracing is indispensable to unraveling the origin, fate, and plasticity of cells. However, the intrinsic leakiness in the CreER-loxP system raises concerns on data interpretation. Here, we reported the generation of a novel dual inducible CreER-loxP system with superior labeling characteristics. This two-component system consists of membrane localized CreER (mCreER: CD8α-FRB-CS-CreER) and TEV protease (mTEVp: CD8α-FKBP-TEVp), which are fusion proteins incorporated with the chemically induced dimerization machinery. Rapamycin and tamoxifen induce sequential dimerization of FKBP and FRB, cleavage of CreER from the membrane, and translocation into the nucleus. The labeling leakiness in Ad293 cells reduced dramatically from more than 70% to less than 5%. This tight labeling feature depends largely on the association of mCreER with HSP90, which conceals the TEV protease cutting site between FRB and CreER and thus preventing uninduced cleavage of the membrane-tethering CreER. Membrane-bound CreER also diminished significantly cytotoxicity. Our studies showed mCreER under the control of the rat insulin promoter increased labeling specificity in MIN6 islet beta-cells. Viability and insulin secretion of MIN6 cells remained intact. Our results demonstrate that this novel system can provide more stringent temporal and spatial control of gene expression and will be useful in cell fate probing.

Direct Differentiation of Human Embryonic Stem Cells to 3D Functional Hepatocyte-like Cells in Alginate Microencapsulation Sphere.

BACKGROUND: The lack of a stable source of hepatocytes is one of major limitations in hepatocyte transplantation and clinical applications of a bioartificial liver. Human embryonic stem cells (hESCs) with a high degree of self-renewal and totipotency are a potentially limitless source of a variety of cell lineages, including hepatocytes. Many techniques have been developed for effective differentiation of hESCs into functional hepatocyte-like cells. However, the application of hESC-derived hepatocyte-like cells (hESC-Heps) in the clinic has been constrained by the low yield of fully differentiated cells, small-scale culture, difficulties in harvesting, and immunologic graft rejection. To resolve these shortcomings, we developed a novel 3D differentiation system involving alginate-microencapsulated spheres to improve current hepatic differentiation, providing ready-to-use hESC-Heps. METHODS: In this study, we used alginate microencapsulation technology to differentiate human embryonic stem cells into hepatocyte-like cells (hESC-Heps). Hepatic markers of hESC-Heps were examined by qPCR and Western blotting, and hepatic functions of hESC-Heps were evaluated by indocyanine-green uptake and release, and ammonia removal. RESULTS: The maturity and hepatic functions of the hESC-Heps derived from this 3D system were better than those derived from 2D culture. Hepatocyte-enriched genes, such as HNF4α, AFP, and ALB, were expressed at higher levels in 3D hESC-Heps than in 2D hESC-Heps. 3D hESC-Heps could metabolize indocyanine green and had better capacity to scavenge ammonia. In addition, the 3D sodium alginate hydrogel microspheres could block viral entry into the microspheres, and thus protect hESC-Heps in 3D microspheres from viral infection. CONCLUSION: We developed a novel 3D differentiation system for differentiating hESCs into hepatocyte-like cells by using alginate microcapsules.

Lipopolysaccharide inhibits macrophage phagocytosis of apoptotic neutrophils by regulating the production of tumour necrosis factor α and growth arrest-specific gene 6.

Removal of apoptotic cells from inflammatory sites by macrophages is an important step in the resolution of inflammation. However, the effect of inflammatory modulators on phagocytic clearance of apoptotic cells remains to be clarified. In this paper, we demonstrate that lipopolysaccharide (LPS), a potent inflammatory agent, inhibits the phagocytosis of apoptotic neutrophils by mouse peritoneal macrophages. This inhibition can be attributed to both LPS-mediated induction of tumour necrosis factor (TNF-α) and suppression of growth arrest-specific gene 6 (Gas6) in macrophages. We found that LPS-induced TNF-α production inhibited phagocytic ability of macrophages in an autocrine manner. In contrast, Gas6 expression in macrophages was blocked by LPS, which also contributes to the inhibition of macrophage phagocytosis by LPS. Our data suggest that phagocytic clearance of apoptotic neutrophils by macrophages can be regulated by local pro- and anti-inflammatory factors in two opposite states.

Obesity and Overweight Are Independently Associated with Greater Survival in Critically Ill Diabetic Patients: A Retrospective Cohort Study.

BACKGROUND: The relationship between obesity and the outcomes of critically ill diabetic patients is not completely clear. We aimed to assess the effects of obesity and overweight on the outcomes among diabetic patients in the intensive care unit (ICU). METHODS: Critically ill diabetic patients in the ICU were classified into three groups according to their body mass index. The primary outcomes were 30-day and 90-day mortality. ICU and hospital length of stay (LOS) and incidence and duration of mechanical ventilation were also assessed. Cox regression models were developed to evaluate the relationship between obesity and overweight and mortality. RESULTS: A total of 6108 eligible patients were included. The 30-day and 90-day mortality in the normal weight group were approximately 1.8 times and 1.5 times higher than in the obesity group and overweight group, respectively (P < 0.001, respectively). Meanwhile, the ICU (median (IQ): 2.9 (1.7, 5.3) vs. 2.7 (1.6, 4.8) vs. 2.8 (1.8, 5.0)) and hospital (median (IQ): 8.3 (5.4, 14.0) vs. 7.9 (5.1, 13.0) vs. 8.3 (5.3, 13.6)) LOS in the obesity group and overweight group were not longer than in the normal weight group. Compared with normal weight patients, obese patients had significantly higher incidence of mechanical ventilation (58.8% vs. 64.7%, P < 0.001) but no longer ventilation duration (median (IQ): 19.3 (7.0, 73.1) vs. 19.0 (6.0, 93.7), P = 1). Multivariate Cox regression showed that obese and overweight patients had lower 30-day (HR (95% CI): 0.62 (0.51, 0.75); 0.76 (0.62, 0.92), respectively) and 90-day (HR (95% CI): 0.60 (0.51, 0.70); 0.79 (0.67, 0.93), respectively) mortality risks than normal weight patients. CONCLUSIONS: Obesity and overweight were independently associated with greater survival in critically ill diabetic patients, without increasing the ICU and hospital LOS. Large multicenter prospective studies are needed to confirm our findings and the underlying mechanisms warrant further investigation.

Doxycycline in Extremely Low Dose Improves Glycemic Control and Islet Morphology in Mice Fed a High-Fat Diet.

PURPOSE: Chronic low-grade inflammation is detected in obese and diabetic individuals. Tetracyclines, used as antibiotics for years, have been demonstrated to have diverse non-bactericidal effects, including anti-tumor and anti-inflammatory activities. This study aimed to investigate whether doxycycline at sub-antimicrobial concentrations could improve glycemic control in mice fed a high-fat diet, through its anti-inflammatory activities. METHODS: C57BL/6J mice were fed with a high-fat diet to induce diabetic and obese conditions. Three sub-antimicrobial dosages of doxycycline (200, 20, and 2 µg/mL) were added to drinking water for 23 weeks during the housing phase. RESULTS: Doxycycline at 200 µg/mL tended to increase body weight, islet mass, and the percentage of large islets (diameter >350 µm). At 20 µg/mL, doxycycline significantly improved glucose tolerance and decreased fasting blood glucose. At 2 µg/mL, doxycycline increased the percentage of small islets (diameter <80 µm). Serum C-reactive protein and lipopolysaccharide levels significantly decreased while the beta-cell ratio increased in all doxycycline-administered mice. CONCLUSION: Our results suggest that doxycycline, even at an extremely low dose, could improve glycemic control and islet morphology via its anti-inflammatory activities.

The Efficacy and Safety of Acellular Matrix Therapy for Diabetic Foot Ulcers: A Meta-Analysis of Randomized Clinical Trials.

BACKGROUND: Acellular matrix (AM) therapy has shown promise in the treatment of diabetic foot ulcers (DFUs) in several studies. The clinical effects of AM therapy were not well established. Therefore, we conducted a meta-analysis of randomized clinical trials (RCTs) to examine the efficacy and safety of AM therapy for patients with DFUs. METHODS: A literature search of 5 databases was performed to identify RCTs comparing AM therapy to standard therapy (ST) in patients with DFUs. The primary outcome was the complete healing rate and the secondary outcomes mainly included time to complete healing and adverse events. RESULTS: Nine RCTs involving 897 patients were included. Compared with ST group, patients allocated to AM group had a higher complete healing rate both at 12 weeks (risk ratio (RR) = 1.73, 95% confidence interval (CI): 1.31 to 2.30) and 16 weeks (RR = 1.56, 95% CI: 1.28 to 1.91), a shorter time to complete healing (mean difference (MD) = -2.41; 95% CI: -3.49 to -1.32), and fewer adverse events (RR = 0.64, 95% CI: 0.44 to 0.93). CONCLUSION: The present study suggests that AM therapy as an adjuvant treatment could further promote the healing of full-thickness, noninfected, and nonischemia DFUs. AM therapy also has a safety profile. More large well-designed randomized clinical trials with long follow-up duration are needed to further explore the efficacy and safety of AM therapy for DFUs.

Classification of Thyroid Nodules with Stacked Denoising Sparse Autoencoder.

PURPOSE: Several commercial tests have been used for the classification of indeterminate thyroid nodules in cytology. However, the geographic inconvenience and high cost confine their widespread use. This study aims to develop a classifier for conveniently clinical utility. METHODS: Gene expression data of thyroid nodule tissues were collected from three public databases. Immune-related genes were used to construct the classifier with stacked denoising sparse autoencoder. RESULTS: The classifier performed well in discriminating malignant and benign thyroid nodules, with an area under the curve of 0.785 [0.638-0.931], accuracy of 92.9% [92.7-93.0%], sensitivity of 98.6% [95.9-101.3%], specificity of 58.3% [30.4-86.2%], positive likelihood ratio of 2.367 [1.211-4.625], and negative likelihood ratio of 0.024 [0.003-0.177]. In the cancer prevalence range of 20-40% for indeterminate thyroid nodules in cytology, the range of negative predictive value of this classifier was 37-61%, and the range of positive predictive value was 98-99%. CONCLUSION: The classifier developed in this study has the superb discriminative ability for thyroid nodules. However, it needs validation in cytologically indeterminate thyroid nodules before clinical use.

The Effect of Inflammation on the Formation of Thyroid Nodules.

BACKGROUND: Some studies have demonstrated that inflammation is highly associated with the prevalence of thyroid nodules (TNs). However, more confounders, such as metabolic diseases, should be adjusted. METHODS: A clinical study collecting 2722 subjects was conducted to confirm the association between inflammation and TNs. The underlying mechanism was investigated in combination with bioinformatics analysis. RESULTS: In the clinical study, propensity score matching was used to match metabolic parameters and other confounders, and it is observed that subjects with high inflammation had a higher prevalence of TNs and thyroid-stimulating hormone (TSH) than those with low inflammation. After further matching TNs, it is found that inflammation was positively associated with TSH, which was also demonstrated in a population without TNs. In bioinformatics study, inflammation did not promote TNs formation directly. Instead, it inhibited the synthesis of thyroid hormone, which might be the cause of the elevated TSH coexisting with inflammation. CONCLUSION: Inflammation promotes the development of TNs disease, probably due to its indirect effect through inhibiting the synthesis of thyroid hormone, which results in the elevation of TSH.

Plasma membrane vesicles of human umbilical cord mesenchymal stem cells ameliorate acetaminophen-induced damage in HepG2 cells: a novel stem cell therapy.

BACKGROUND: Acetaminophen (APAP) overdose is the common cause of acute liver failure (ALF) due to the oxidative damage of multiple cellular components. This study aimed to investigate whether plasma membrane vesicles (PMVs) from human umbilical cord mesenchymal stem cells (hUCMSCs) could be exploited as a novel stem cell therapy for APAP-induced liver injury. METHODS: PMVs from hUCMSCs were prepared with an improved procedure including a chemical enucleation step followed by a mechanical extrusion. PMVs of hUCMSCs were characterized and supplemented to hepatocyte cultures. Rescue of APAP-induced hepatocyte damage was evaluated. RESULTS: The hUCMSCs displayed typical fibroblastic morphology and multipotency when cultivated under adipogenic, osteogenic, or chondrogenic conditions. PMVs of hUCMSCs maintained the stem cell phenotype, including the presence of CD13, CD29, CD44, CD73, and HLA-ABC, but the absence of CD45, CD117, CD31, CD34, and HLA-DR on the plasma membrane surface. RT-PCR and transcriptomic analyses showed that PMVs were similar to hUCMSCs in terms of mRNA profile, including the expression of stemness genes GATA4/5/6, Nanog, and Oct1/2/4. GO term analysis showed that the most prominent reduced transcripts in PMVs belong to integral membrane components, extracellular vesicular exosome, and extracellular matrix. Immunofluorescence labeling/staining and confocal microscopy assays showed that PMVs enclosed cellular organelles, including mitochondria, lysosomes, proteasomes, and endoplasmic reticula. Incorporation of the fusogenic VSV-G viral membrane glycoprotein stimulated the endosomal release of PMV contents into the cytoplasm. Further, the addition of PMVs and a mitochondrial-targeted antioxidant Mito-Tempo into cultures of APAP-treated HepG2 cells resulted in reduced cell death, enhanced viability, and increased mitochondrial membrane potential. Lastly, this study demonstrated that the redox state and activities of aminotransferases were restored in APAP-treated HepG2 cells. CONCLUSIONS: The results suggest that PMVs from hUCMSCs could be used as a novel stem cell therapy for the treatment of APAP-induced liver injury.