Positive feedback regulation between glycolysis and histone lactylation drives oncogenesis in pancreatic ductal adenocarcinoma.

BACKGROUND: Metabolic reprogramming and epigenetic alterations contribute to the aggressiveness of pancreatic ductal adenocarcinoma (PDAC). Lactate-dependent histone modification is a new type of histone mark, which links glycolysis metabolite to the epigenetic process of lactylation. However, the role of histone lactylation in PDAC remains unclear. METHODS: The level of histone lactylation in PDAC was identified by western blot and immunohistochemistry, and its relationship with the overall survival was evaluated using a Kaplan-Meier survival plot. The participation of histone lactylation in the growth and progression of PDAC was confirmed through inhibition of histone lactylation by glycolysis inhibitors or lactate dehydrogenase A (LDHA) knockdown both in vitro and in vivo. The potential writers and erasers of histone lactylation in PDAC were identified by western blot and functional experiments. The potential target genes of H3K18 lactylation (H3K18la) were screened by CUT&Tag and RNA-seq analyses. The candidate target genes TTK protein kinase (TTK) and BUB1 mitotic checkpoint serine/threonine kinase B (BUB1B) were validated through ChIP-qPCR, RT-qPCR and western blot analyses. Next, the effects of these two genes in PDAC were confirmed by knockdown or overexpression. The interaction between TTK and LDHA was identified by Co-IP assay. RESULTS: Histone lactylation, especially H3K18la level was elevated in PDAC, and the high level of H3K18la was associated with poor prognosis. The suppression of glycolytic activity by different kinds of inhibitors or LDHA knockdown contributed to the anti-tumor effects of PDAC in vitro and in vivo. E1A binding protein p300 (P300) and histone deacetylase 2 were the potential writer and eraser of histone lactylation in PDAC cells, respectively. H3K18la was enriched at the promoters and activated the transcription of mitotic checkpoint regulators TTK and BUB1B. Interestingly, TTK and BUB1B could elevate the expression of P300 which in turn increased glycolysis. Moreover, TTK phosphorylated LDHA at tyrosine 239 (Y239) and activated LDHA, and subsequently upregulated lactate and H3K18la levels. CONCLUSIONS: The glycolysis-H3K18la-TTK/BUB1B positive feedback loop exacerbates dysfunction in PDAC. These findings delivered a new exploration and significant inter-relationship between lactate metabolic reprogramming and epigenetic regulation, which might pave the way toward novel lactylation treatment strategies in PDAC therapy.

Gut Microbiota-Tryptophan Metabolism-GLP-1 Axis Participates in ß-Cell Regeneration Induced by Dapagliflozin.

Sodium-glucose cotransporter 2 inhibitors, efficacious antidiabetic agents that have cardiovascular and renal benefits, can promote pancreatic ß-cell regeneration in type 2 diabetic mice. However, the underlying mechanism remains unclear. In this study, we aimed to use multiomics to identify the mediators involved in ß-cell regeneration induced by dapagliflozin. We showed that dapagliflozin lowered blood glucose level, upregulated plasma insulin level, and increased islet area in db/db mice. Dapagliflozin reshaped gut microbiota and modulated microbiotic and plasmatic metabolites related to tryptophan metabolism, especially l-tryptophan, in the diabetic mice. Notably, l-tryptophan upregulated the mRNA level of glucagon-like peptide 1 (GLP-1) production-related gene (Gcg and Pcsk1) expression and promoted GLP-1 secretion in cultured mouse intestinal L cells, and it increased the supernatant insulin level in primary human islets, which was eliminated by GPR142 antagonist. Transplant of fecal microbiota from dapagliflozin-treated mice, supplementation of l-tryptophan, or treatment with dapagliflozin upregulated l-tryptophan, GLP-1, and insulin or C-peptide levels and promoted ß-cell regeneration in db/db mice. Addition of exendin 9-39, a GLP-1 receptor (GLP-1R) antagonist, or pancreatic Glp1r knockout diminished these beneficial effects. In summary, treatment with dapagliflozin in type 2 diabetic mice promotes ß-cell regeneration by upregulating GLP-1 production, which is mediated via gut microbiota and tryptophan metabolism.

Correction: Mitochondria-targeting nanozyme alleviating temporomandibular joint pain by inhibiting the TNFα/NF-κB/NEAT1 pathway.

Correction for 'Mitochondria-targeting nanozyme alleviating temporomandibular joint pain by inhibiting the TNFα/NF-κB/NEAT1 pathway' by Qian Bai et al., J. Mater. Chem. B, 2023, https://doi.org/10.1039/d3tb00929g.

Transcriptome-wide analysis of trigeminal ganglion and subnucleus caudalis in a mouse model of chronic constriction injury-induced trigeminal neuralgia.

Trigeminal neuropathic pain (TNP) induces mechanical allodynia and hyperalgesia, which are known to alter gene expression in injured dorsal root ganglia primary sensory neurons. Non-coding RNAs (ncRNAs) have been linked to TNP. However, the functional mechanism underlying TNP and the expression profile of ncRNAs in the trigeminal ganglion (TG) and trigeminal subnucleus caudalis (Sp5C) are still unknown. We used RNA sequencing and bioinformatics analysis to examine the TG and Sp5C transcriptomes after infraorbital nerve chronic constrictive injury (IoN-CCI). The robust changes in the gene expression of lncRNAs, circRNAs, and mRNAs were observed within the TG and Sp5C from mice that underwent IoN-CCI and the sham-operated mice (day 7). In total, 111,003 lncRNAs were found in TG and 107,157 in Sp5C; 369 lncRNAs were differentially expressed in TG, and 279 lncRNAs were differentially expressed in Sp5C. In addition, 13,216 circRNAs in TG and 21,658 circRNAs in Sp5C were identified, with 1,155 circRNAs and 2,097 circRNAs differentially expressed in TG and Sp5C, respectively. Furthermore, 5,205 DE mRNAs in TG and 3,934 DE mRNAs in Sp5C were differentially expressed between IoN-CCI and sham groups. The study revealed a high correlation of pain-related differentially expressed genes in the TG and Sp5C to anxiety, depression, inflammation, neuroinflammation, and apoptosis. Gene Ontology analysis revealed that binding-related molecular functions and membrane-related cell components were significantly enriched. Kyoto Encyclopedia of Genes and Genomes analysis shows the most significant enrichments in neurogenesis, nervous system development, neuron differentiation, adrenergic signaling, cAMP signaling, MAPK signaling, and PI3K-Akt signaling pathways. Furthermore, protein-protein interaction analysis showed that hub genes were implicated in neuropeptide signaling pathways. Functional analysis of DE ncRNA-targeting genes was mostly enriched with nociception-related signaling pathways underpinning TNP. Our findings suggest that ncRNAs are involved in TNP development and open new avenues for research and treatment.

Mitochondria-targeting nanozyme alleviating temporomandibular joint pain by inhibiting the TNFα/NF-κB/NEAT1 pathway.

Inflammatory cytokines that are secreted into the spinal trigeminal nucleus caudalis (Sp5C) may augment inflammation and cause pain associated with temporomandibular joint disorders (TMD). In a two-step process, we attached triphenylphosphonium (TPP) to the surface of a cubic liposome metal-organic framework (MOF) loaded with ruthenium (Ru) nanozyme. The design targeted mitochondria and was designated Mito-Ru MOF. This structure scavenges free radicals and reactive oxygen species (ROS) and alleviates oxidative stress. The present study aimed to investigate the effects and mechanisms by which Mito-Ru MOF ameliorates TMD pain. Intra-temporomandibular joint (TMJ) injections of complete Freund's adjuvant (CFA) induced inflammatory pain for ≥10 d in the skin areas innervated by the trigeminal nerve. Tumor necrosis factor-alpha (TNF-α), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), long non-coding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1), and ROS also have been proved to be significantly upregulated in the Sp5C of TMD mice. Moreover, a single Mito-Ru MOF treatment alleviated TMD pain for 3 d and downregulated TNF-α, NF-κB, lncRNA NEAT1, and ROS. NF-κB knockdown downregulated NEAT1 in the TMD mice. Hence, Mito-Ru MOF inhibited the production of ROS and alleviated CFA-induced TMD pain via the TNF-α/NF-κB/NEAT1 pathway. Therefore, Mito-Ru MOF could effectively treat the pain related to TMD and other conditions associated with severe acute inflammatory activation.

Fatty acid ß-oxidation and mitochondrial fusion are involved in cardiac microvascular endothelial cell protection induced by glucagon receptor antagonism in diabetic mice.

INTRODUCTION: The role of cardiac microvascular endothelial cells (CMECs) in diabetic cardiomyopathy is not fully understood. We aimed to investigate whether a glucagon receptor (GCGR) monoclonal antibody (mAb) ameliorated diabetic cardiomyopathy and clarify whether and how CMECs participated in the process. RESEARCH DESIGN AND METHODS: The db/db mice were treated with GCGR mAb or immunoglobulin G (as control) for 4 weeks. Echocardiography was performed to evaluate cardiac function. Immunofluorescent staining was used to determine microvascular density. The proteomic signature in isolated primary CMECs was analyzed by using tandem mass tag-based quantitative proteomic analysis. Some target proteins were verified by using western blot. RESULTS: Compared with db/m mice, cardiac microvascular density and left ventricular diastolic function were significantly reduced in db/db mice, and this reduction was attenuated by GCGR mAb treatment. A total of 199 differentially expressed proteins were upregulated in db/db mice versus db/m mice and downregulated in GCGR mAb-treated db/db mice versus db/db mice. The enrichment analysis demonstrated that fatty acid ß-oxidation and mitochondrial fusion were the key pathways. The changes of the related proteins carnitine palmitoyltransferase 1B, optic atrophy type 1, and mitofusin-1 were further verified by using western blot. The levels of these three proteins were upregulated in db/db mice, whereas this upregulation was attenuated by GCGR mAb treatment. CONCLUSION: GCGR antagonism has a protective effect on CMECs and cardiac diastolic function in diabetic mice, and this beneficial effect may be mediated via inhibiting fatty acid ß-oxidation and mitochondrial fusion in CMECs.

Association of triglyceride-glucose index with major depressive disorder: A cross-sectional study.

The triglyceride-glucose (TyG) index has been proposed as a new marker for insulin resistance, which is associated with a risk of major depressive disorder (MDD). This study aims to explore whether the TyG index is correlated with MDD. In total, 321 patients with MDD and 325 non-MDD patients were included in the study. The presence of MDD was identified by trained clinical psychiatrists using the International Classification of Diseases 10th Revision. The TyG index was calculated as follows: Ln (fasting triglyceride [mg/dL] × fasting glucose [mg/dL]/2). The results revealed that the MDD group presented higher TyG index values than the non-MDD group (8.77 [8.34-9.17] vs 8.62 [8.18-9.01], P < .001). We also found significantly higher morbidity of MDD in the highest TyG index group than in the lower TyG index group (59.9% vs 41.4%, P < .001). Binary logistic regression revealed that TyG was an independent risk factor for MDD (odds ratio [OR] 1.750, 95% confidence interval: 1.284-2.384, P < .001). We further assessed the effect of TyG on depression in sex subgroups. The OR was 3.872 (OR 2.014, 95% confidence interval: 1.282-3.164, P = .002) for the subgroup of men. It is suggested that the TyG index could be closely associated with morbidity in MDD patients; thus, it may be a valuable marker for identifying MDD.

Glucagon Acting at the GLP-1 Receptor Contributes to ß-Cell Regeneration Induced by Glucagon Receptor Antagonism in Diabetic Mice.

Dysfunction of glucagon-secreting α-cells participates in the progression of diabetes, and glucagon receptor (GCGR) antagonism is regarded as a novel strategy for diabetes therapy. GCGR antagonism upregulates glucagon and glucagon-like peptide 1 (GLP-1) secretion and, notably, promotes ß-cell regeneration in diabetic mice. Here, we aimed to clarify the role of GLP-1 receptor (GLP-1R) activated by glucagon and/or GLP-1 in the GCGR antagonism-induced ß-cell regeneration. We showed that in db/db mice and type 1 diabetic wild-type or Flox/cre mice, GCGR monoclonal antibody (mAb) improved glucose control, upregulated plasma insulin level, and increased ß-cell area. Notably, blockage of systemic or pancreatic GLP-1R signaling by exendin 9-39 (Ex9) or Glp1r knockout diminished the above effects of GCGR mAb. Furthermore, glucagon-neutralizing antibody (nAb), which prevents activation of GLP-1R by glucagon, also attenuated the GCGR mAb-induced insulinotropic effect and ß-cell regeneration. In cultured primary mouse islets isolated from normal mice and db/db mice, GCGR mAb action to increase insulin release and to upregulate ß-cell-specific marker expression was reduced by a glucagon nAb, by the GLP-1R antagonist Ex9, or by a pancreas-specific Glp1r knockout. These findings suggest that activation of GLP-1R by glucagon participates in ß-cell regeneration induced by GCGR antagonism in diabetic mice. ARTICLE HIGHLIGHTS: Glucagon receptor (GCGR) antagonism promotes ß-cell regeneration in type 1 and type 2 diabetic mice and in euglycemic nonhuman primates. Glucagon and glucagon-like peptide 1 (GLP-1) can activate the GLP-1 receptor (GLP-1R), and their levels are upregulated following GCGR antagonism. We investigated whether GLP-1R activated by glucagon and/or GLP-1 contributed to ß-cell regeneration induced by GCGR antagonism. We found that blockage of glucagon-GLP-1R signaling attenuated the GCGR monoclonal antibody-induced insulinotropic effect and ß-cell regeneration in diabetic mice. Our study reveals a novel mechanism of ß-cell regeneration and uncovers the communication between α-cells and ß-cells in regulating ß-cell mass.

Pancreatic alpha cell glucagon-liver FGF21 axis regulates beta cell regeneration in a mouse model of type 2 diabetes.

AIMS/HYPOTHESIS: Glucagon receptor (GCGR) antagonism ameliorates hyperglycaemia and promotes beta cell regeneration in mouse models of type 2 diabetes. However, the underlying mechanisms remain unclear. The present study aimed to investigate the mechanism of beta cell regeneration induced by GCGR antagonism in mice. METHODS: The db/db mice and high-fat diet (HFD)+streptozotocin (STZ)-induced mice with type 2 diabetes were treated with antagonistic GCGR monoclonal antibody (mAb), and the metabolic variables and islet cell quantification were evaluated. Plasma cytokine array and liver RNA sequencing data were used to screen possible mediators, including fibroblast growth factor 21 (FGF21). ELISA, quantitative RT-PCR and western blot were applied to verify FGF21 change. Blockage of FGF21 signalling by FGF21-neutralising antibody (nAb) was used to clarify whether FGF21 was involved in the effects of GCGR mAb on the expression of beta cell identity-related genes under plasma-conditional culture and hepatocyte co-culture conditions. FGF21 nAb-treated db/db mice, systemic Fgf21-knockout (Fgf21-/-) diabetic mice and hepatocyte-specific Fgf21-knockout (Fgf21Hep-/-) diabetic mice were used to reveal the involvement of FGF21 in beta cell regeneration. A BrdU tracing study was used to analyse beta cell proliferation in diabetic mice treated with GCGR mAb. RESULTS: GCGR mAb treatment improved blood glucose control, and increased islet number (db/db 1.6±0.1 vs 0.8±0.1 per mm2, p<0.001; HFD+STZ 1.2±0.1 vs 0.5±0.1 per mm2, p<0.01) and area (db/db 2.5±0.2 vs 1.2±0.2%, p<0.001; HFD+STZ 1.0±0.1 vs 0.3±0.1%, p<0.01) in diabetic mice. The plasma cytokine array and liver RNA sequencing data showed that FGF21 levels in plasma and liver were upregulated by GCGR antagonism. The GCGR mAb induced upregulation of plasma FGF21 levels (db/db 661.5±40.0 vs 466.2±55.7 pg/ml, p<0.05; HFD+STZ 877.0±106.8 vs 445.5±54.0 pg/ml, p<0.05) and the liver levels of Fgf21 mRNA (db/db 3.2±0.5 vs 1.8±0.1, p<0.05; HFD+STZ 2.0±0.3 vs 1.0±0.2, p<0.05) and protein (db/db 2.0±0.2 vs 1.4±0.1, p<0.05; HFD+STZ 1.6±0.1 vs 1.0±0.1, p<0.01). Exposure to plasma or hepatocytes from the GCGR mAb-treated mice upregulated the mRNA levels of characteristic genes associated with beta cell identity in cultured mouse islets and a beta cell line, and blockage of FGF21 activity by an FGF21 nAb diminished this upregulation. Notably, the effects of increased beta cell number induced by GCGR mAb were attenuated in FGF21 nAb-treated db/db mice, Fgf21-/- diabetic mice and Fgf21Hep-/- diabetic mice. Moreover, GCGR mAb treatment enhanced beta cell proliferation in the two groups of diabetic mice, and this effect was weakened in Fgf21-/- and Fgf21Hep-/- mice. CONCLUSIONS/INTERPRETATION: Our findings demonstrate that liver-derived FGF21 is involved in the GCGR antagonism-induced beta cell regeneration in a mouse model of type 2 diabetes.

Glucagon receptor blockage inhibits ß-cell dedifferentiation through FoxO1.

Glucagon-secreting pancreatic α-cells play pivotal roles in the development of diabetes. Glucagon promotes insulin secretion from ß-cells. However, the long-term effect of glucagon on the function and phenotype of ß-cells had remained elusive. In this study, we found that long-term glucagon intervention or glucagon intervention with the presence of palmitic acid downregulated ß-cell-specific markers and inhibited insulin secretion in cultured ß-cells. These results suggested that glucagon induced ß-cell dedifferentiation under pathological conditions. Glucagon blockage by a glucagon receptor (GCGR) monoclonal antibody (mAb) attenuated glucagon-induced ß-cell dedifferentiation. In primary islets, GCGR mAb treatment upregulated ß-cell-specific markers and increased insulin content, suggesting that blockage of endogenous glucagon-GCGR signaling inhibited ß-cell dedifferentiation. To investigate the possible mechanism, we found that glucagon decreased FoxO1 expression. FoxO1 inhibitor mimicked the effect of glucagon, whereas FoxO1 overexpression reversed the glucagon-induced ß-cell dedifferentiation. In db/db mice and ß-cell lineage-tracing diabetic mice, GCGR mAb lowered glucose level, upregulated plasma insulin level, increased ß-cell area, and inhibited ß-cell dedifferentiation. In aged ß-cell-specific FoxO1 knockout mice (with the blood glucose level elevated as a diabetic model), the glucose-lowering effect of GCGR mAb was attenuated and the plasma insulin level, ß-cell area, and ß-cell dedifferentiation were not affected by GCGR mAb. Our results proved that glucagon induced ß-cell dedifferentiation under pathological conditions, and the effect was partially mediated by FoxO1. Our study reveals a novel cross talk between α- and ß-cells and is helpful to understand the pathophysiology of diabetes and discover new targets for diabetes treatment.NEW & NOTEWORTHY Glucagon-secreting pancreatic α-cells can interact with ß-cells. However, the long-term effect of glucagon on the function and phenotype of ß-cells has remained elusive. Our new finding shows that long-term glucagon induces ß-cell dedifferentiation in cultured ß-cells. FoxO1 inhibitor mimicks whereas glucagon signaling blockage by GCGR mAb reverses the effect of glucagon. In type 2 diabetic mice, GCGR mAb increases ß-cell area, improves ß-cell function, and inhibits ß-cell dedifferentiation, and the effect is partially mediated by FoxO1.

Dapagliflozin improves pancreatic islet function by attenuating microvascular endothelial dysfunction in type 2 diabetes.

AIMS: Sodium-glucose co-transporter 2 inhibitors, including dapagliflozin, improve ß cell function in type 2 diabetic individuals. Whether dapagliflozin can protect islet microvascular endothelial cells (IMECs) and thus contribute to the improvement of ß cell function remains unknown. MATERIALS AND METHODS: The db/db mice were treated with dapagliflozin or vehicle for 6 weeks. ß cell function, islet capillaries and the levels of inflammatory chemokines in IMECs were detected. The mouse IMEC cell line MS-1 cells were incubated with palmitate and/or dapagliflozin for 24 h. Angiogenesis and inflammatory chemokine levels were evaluated, and the involved signalling pathways were analysed. The mouse ß cell line MIN6 cells, in the presence or absence of co-culture with MS-1 cells, were treated with palmitate and/or dapagliflozin for 24 h. The expression of ß cell specific markers and insulin secretion in MIN6 cells were determined. RESULTS: Dapagliflozin significantly improved ß cell function, increased islet capillaries and decreased the levels of inflammatory chemokines of IMECs in db/db mice. In the palmitate-treated MS-1 cells, angiogenesis was enhanced and the levels of inflammatory chemokines were downregulated by dapagliflozin. Either a PI3K inhibitor or mTOR inhibitor eliminated the dapagliflozin-mediated effects. Importantly, dapagliflozin attenuated the palmitate-induced downregulation of ß cell function-related gene expression and insulin secretion in MIN6 cells co-cultured with MS-1 cells but not in those on mono-culture. CONCLUSIONS: Dapagliflozin restores islet vascularisation and attenuates the inflammation of IMECs in type 2 diabetic mice. The dapagliflozin-induced improvement of ß cell function is at least partially accounted for by its beneficial effects on IMECs in a PI3K/Akt-mTOR-dependent manner.

γ-aminobutyric acid modulates α-cell hyperplasia but not ß-cell regeneration induced by glucagon receptor antagonism in type 1 diabetic mice.

AIMS: To investigate whether treatment with γ-aminobutyric acid (GABA) alone or in combination with glucagon receptor (GCGR) monoclonal antibody (mAb) exerted beneficial effects on ß-cell mass and α-cell mass, and to explore the origins of the regenerated ß-cells in mice with type 1 diabetes (T1D). METHODS: Streptozotocin (STZ)-induced T1D mice were treated with intraperitoneal injection of GABA (250 µg/kg per day) and/or REMD 2.59 (a GCGR mAb, 5 mg/kg per week), or IgG dissolved in PBS for 8 weeks. Plasma hormone levels and islet cell morphology were evaluated by ELISA and immunofluorescence, respectively. The origins of the regenerated ß-cells were analyzed by double-immunostaining, α-cell lineage-tracing and BrdU-tracing studies. RESULTS: After the 8-week treatment, GABA or GCGR mAb alone or in combination ameliorated hyperglycemia in STZ-induced T1D mice. GCGR mAb upregulated plasma insulin level and increased ß-cell mass, and GABA appeared to have similar effects in T1D mice. However, combination treatment did not reveal any additive or synergistic effect. Interestingly, the GCGR mAb-induced increment of plasma glucagon level and α-cell mass was attenuated by the combined treatment of GABA. In addition, duct-derived ß-cell neogenesis and α-to-ß cell conversion but not ß-cell proliferation contributed to the increased ß-cell mass in T1D mice. CONCLUSION: These results suggested that GABA attenuated α-cell hyperplasia but did not potentiates ß-cell regeneration induced by GCGR mAb in T1D mice. Our findings provide novel insights into a combination treatment strategy for ß-cell regeneration in T1D.

RNA sequencing profiling of mRNAs, long noncoding RNAs, and circular RNAs in Trigeminal Ganglion following Temporomandibular Joint inflammation.

Patients with temporomandibular joint disorders (TMD) have high levels of inflammatory pain-related disability, which seriously affects their physical and mental health. However, an effective treatment is yet to be developed. Both circular RNAs (circRNAs) and long noncoding RNAs (lncRNAs) contribute to regulating pain conduction. In our current study, we report the expression profiles of circRNAs, lncRNAs, and mRNAs in the trigeminal ganglion (TG) associated with complete Freund's adjuvant (CFA)-induced TMD inflammation pain. The collected TGs from the experimental (CFA) and control (saline) groups were processed for deep RNA sequencing. Overall, 1078,909,068 clean reads were obtained. A total of 15,657 novel lncRNAs were identified, where 281 lncRNAs were differentially expressed on CFA3D and 350 lncRNAs were differentially expressed on CFA6D. In addition, a total of 55,441 mRNAs and 27,805 circRNAs were identified, where 3,914 mRNAs and 91 circRNAs were found differentially expressed, between the CFA3D and saline groups, while 4,232 mRNAs and 98 DE circRNAs were differentially expressed between the CFA6D and saline groups. Based on functional analyses, we found that the most significant enriched biological processes of the upregulated mRNAs were involved in the immunity, neuron projection, inflammatory response, MAPK signaling pathway, Ras signaling pathway, chemokine signaling pathway, and inflammatory response in TG. Further analyses of Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes pathway suggest the involvement of dysregulated genes in the pain occurrence mechanism. Our findings provide a resource for expression patterns of gene transcripts in regions related to pain. These results suggest that apoptosis and neuroinflammation are important pathogenic mechanisms underlying TMD pain. Some of the reported differentially expressed genes might be considered promising therapeutic targets. The current research study revealed the expression profiles of circRNAs, lncRNAs, and mRNAs during TMD inflammation pain and sheds light on the roles of circRNAs and lncRNAs underlying the pain pathway in the trigeminal system of TMD inflammation pain.

Advances in endoscopic resection techniques of small gastric tumors originating from the muscularis propria.

Gastrointestinal stromal tumors are common gastrointestinal tumors typically originating from the muscularis propria layer of the stomach. Small gastric stromal tumors are usually detected incidentally during routine endoscopic examination. Although they may have malignant potentially, controversies remain regarding the need for endoscopic resection of small gastric stromal tumors originating from the muscularis propria. According to the guidelines of the European Society of Medical Oncology, all gastrointestinal stromal tumors >2 cm in size should be resected with endoscopic surveillance recommended for tumors <2 cm. Endoscopic resection including endoscopic mucosal dissection (EMD), endoscopic submucosal dissection (ESD), submucosal tunneling endoscopic resection and snare assisted endoscopic resection. However, EMD and ESD procedures may be accompanied with serious complications including perforation, bleeding, and abdominal infection. Snare-assisted endoscopic resection is an alternative approach and has the advantages of a shorter procedure time and a low rate of perforation or bleeding. This study summarizes the safety and feasibility of a novel snare-assisted endoscopic resection technique and highlights the pros and cons of the different endoscopic approaches currently used for subepithelia small gastric tumors.

Pro-α-cell-derived ß-cells contribute to ß-cell neogenesis induced by antagonistic glucagon receptor antibody in type 2 diabetic mice.

The deficiency of pancreatic ß-cells is the key pathogenesis of diabetes, while glucagon-secreting α-cells are another player in the development of diabetes. Here, we aimed to investigate the effects of glucagon receptor (GCGR) antagonism on ß-cell neogenesis in type 2 diabetic (T2D) mice and explore the origins of the neogenic ß-cells. We showed that GCGR monoclonal antibody (mAb) elevated plasma insulin level and increased ß-cell mass in T2D mice. By using α-cell lineage-tracing (glucagon -cre -ß-gal) mice and inducible Ngn3+ pancreatic endocrine progenitor lineage-tracing (Ngn3-CreERT2-tdTomato) mice, we found that GCGR mAb treatment promoted α-cell regression to progenitors, and induced Ngn3+ progenitor reactivation and differentiation toward ß-cells. Besides, GCGR mAb upregulated the expression levels of ß-cell regeneration-associated genes and promoted insulin secretion in primary mouse islets, indicative of a direct effect on ß-cell identity. Our findings suggest that GCGR antagonism not only increases insulin secretion but also promotes pro-α-cell-derived ß-cell neogenesis in T2D mice.

Self-Assembly of Polystyrene-b-poly(2-vinylpyridine)/Chloroauric Acid at the Liquid/Liquid Interface.

The self-assembly of polystyrene-block-poly(2-vinylpyridine) at the liquid/liquid interface has been systematically investigated to develop a series of primary morphologies of the aggregates. The block copolymers self-assembled into large areas of nanodot arrays, parallel nanostrands, layered films, parallel nanobelts, honeycomb monolayers, and foams by reacting with chloroauric acid, depending on the molecular structure of the block copolymers and the amount of chloroauric acid. The formation of the first four ordered structures resulted from interfacial adsorption and self-assembly, and nucleation and epitaxial growth. The latter two structures were attributed to the water hole templating effect and spontaneous interfacial emulsification, respectively. This work provides insight into the self-assembly behavior of block copolymers at the interface and provides a facile approach for fabricating functional structures.

NUA and ESD4 negatively regulate ABA signaling during seed germination.

The phytohormone abscisic acid (ABA) plays important roles in plant growth, development and adaptative responses to abiotic stresses. SNF1-related protein kinase 2s (SnRK2) are key components that activate the ABA core signaling pathway. NUCLEAR PORE ANCHOR (NUA) is a component of the nuclear pore complex (NPC) that involves in deSUMOylation through physically interacting with the EARLY IN SHORT DAYS 4 (ESD4) SUMO protease. However, it is not clear how NUA functions with SnRK2 and ESD4 to regulate ABA signaling. In our study, we found that nua loss-of-function mutants exhibited pleiotropic ABA-hypersensitive phenotype. We also found that ABA-responsive genes remarkably up-regulated in nua by exogenous ABA. The nua snrk2.2 snrk2.3 triple mutant and nua abi5 double mutant partially rescued the ABA-hypersensitive phenotype of nua, thereby suggesting that NUA is epistatic to SnRK2s. Additionally, we observed that esd4-3 mutant was also ABA-hypersensitive. NUA and ESD4 were further demonstrated to physically interact with SnRK2s and negatively regulate ABA signaling by reducing SnRK2s stability. Taken together, our findings uncover a new regulatory mechanism that can modulate ABA signaling.

Identification of key genes and pathways in mild and severe nonalcoholic fatty liver disease by integrative analysis.

BACKGROUND: The global prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing. The pathogenesis of NAFLD is multifaceted, and the underlying mechanisms are elusive. We conducted data mining analysis to gain a better insight into the disease and to identify the hub genes associated with the progression of NAFLD. METHODS: The dataset GSE49541, containing the profile of 40 samples representing mild stages of NAFLD and 32 samples representing advanced stages of NAFLD, was acquired from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified using the R programming language. The Database for Annotation, Visualization and Integrated Discovery (DAVID) online tool and Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database were used to perform the enrichment analysis and construct protein-protein interaction (PPI) networks, respectively. Subsequently, transcription factor networks and key modules were identified. The hub genes were validated in a mice model of high fat diet (HFD)-induced NAFLD and in cultured HepG2 cells by real-time quantitative PCR. RESULTS: Based on the GSE49541 dataset, 57 DEGs were selected and enriched in chemokine activity and cellular component, including the extracellular region. Twelve transcription factors associated with DEGs were indicated from PPI analysis. Upregulated expression of five hub genes (SOX9, CCL20, CXCL1, CD24, and CHST4), which were identified from the dataset, was also observed in the livers of HFD-induced NAFLD mice and in HepG2 cells exposed to palmitic acid or advanced glycation end products. CONCLUSION: The hub genes SOX9, CCL20, CXCL1, CD24, and CHST4 are involved in the aggravation of NAFLD. Our results offer new insights into the underlying mechanism of NAFLD progression.

Gut microbiota mediates the effects of curcumin on enhancing Ucp1-dependent thermogenesis and improving high-fat diet-induced obesity.

Due to extremely poor systemic bioavailability, the mechanism by which curcumin increases energy expenditure remains unelucidated. Accumulating evidence suggests a strong association between the gut microbiota (GM) and energy metabolism. We investigated whether the GM mediates the effects of curcumin on improving energy homeostasis. High-fat diet (HFD)-fed wild type, uncoupling protein 1 (Ucp1) knockout and G protein-coupled membrane receptor 5 (TGR5) knockout mice were treated with curcumin (100 mg kg-1 d-1, p.o.). Curcumin-treated HFD-fed mice displayed decreased body weight gain and augmented cold tolerance due to enhanced adaptive thermogenesis as compared with that in control mice. The anti-obesity effects of curcumin were abolished by Ucp1 knockout. 16S ribosomal DNA sequencing analysis revealed that curcumin restructured the GM in HFD-fed mice. Fecal microbiota transplantation (FMT) and endogenous GM depletion indicated that the GM mediated the enhanced effect of curcumin on Ucp1-dependent thermogenesis. Curcumin altered bile acid (BA) metabolism with increased fractions of circulating deoxycholic acid (DCA) and lithocholic acid (LCA), which are the two most potent ligands for TGR5. Consistently, the enhanced effect of curcumin on Ucp1-dependent thermogenesis was eliminated by TGR5 knockout. Curcumin requires the GM and TGR5 to activate the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) signaling pathway in thermogenic adipose tissue. Here, we demonstrated that the GM mediates the effects of curcumin on enhancing Ucp1-dependent thermogenesis and ameliorating HFD-induced obesity by influencing BA metabolism. We disclosed the potential of nutritional and pharmacologic manipulations of the GM to enhance Ucp1-dependent thermogenesis in the prevention and treatment of obesity.

General Control Non-derepressible 1 (AtGCN1) Is Important for Flowering Time, Plant Growth, Seed Development, and the Transcription/Translation of Specific Genes in Arabidopsis.

We have previously demonstrated that General Control Non-derepressible 1 (AtGCN1) is essential for translation inhibition under cold stress through interacting with GCN2 to phosphorylate eukaryotic translation initiation factor 2 (eIF2). Here, we report that the flower time of the atgcn1 mutant is later than that of the wild type (WT), and some siliques of atgcn1 cannot develop and produce seeds. Total and polysomal RNA of atgcn1-1 and wild type (WT) after cold treatments were sequenced. The sequencing results show that the mutation of atgcn1 selectively alters the expression of genes at both transcriptional and translational levels. The classification of AtGCN1 target genes reveals that AtGCN1 regulated gens are involved in flower development, seed dormancy and seed development, response to osmotic stress, amino acid biosynthesis, photosynthesis, cell wall organization, protein transport and localization, lipid biosynthesis, transcription, macroautophagy, proteolysis and cell death. Further analysis of AtGCN1 regulated genes at translational levels shows that the Kozak sequence and uORFs (upstream open reading frame) of transcripts affect translation selection. These results show that AtGCN1 is required for the expression of selective genes in Arabidopsis.