Discovery of octahydropyrrolo [3,2-b] pyridin derivative as a highly selective Type I inhibitor of FGFR3 over VEGFR2 by high-throughput virtual screening.

Although the aberrant activity of fibroblast growth factor receptor 3 (FGFR3) is implicated in various cancers, the reported kinase inhibitors of FGFR3 tend to cause side effects resulting from the inhibitory activity on vascular endothelial growth factor receptor 2 (VEGFR2). Therefore, it is necessary to find a novel high-selective inhibitor of FGFR3 over VEGFR2 from the small-molecule compound database. In this study, integrated virtual screening protocols were established to screen for selective inhibitors of FGFR3 over VEGFR2 in Drugbank and Asinex databases by combining three-dimensional pharmacophore model, molecular docking, molecular dynamics (MD) simulation, and molecular mechanics Poisson-Boltzmann surface area (MMPBSA) calculations. Finally, it is found that Asinex-5082, as an octahydropyrrolo[3,2-b] pyridin derivative, has larger binding free energy with FGFR3 (-39.3 kcal/mol) than reference drug Erdafitinib (-29.9 kcal/mol), while cannot bind with VEGFR2, resulting in considerable inhibitory selectivity. This is because Asinex-5082, unlike Erdafitinib, has not m-dimethoxybenzene with large steric hindrance, thus can enter the larger ATP-binding pocket of FGFR3 with DFG-in conformation to form hydrophobic interaction with residues Met529, Ile539, and Tyr557 as well as hydrogen bond with Ala558. On the other hand, due to the fact that the benzodioxane and N-heterocyclic rings are connected by carbonyl (C=O), Asinex-5082 cannot rotate freely so as to enter the smaller ATP binding pocket of VEGFR2 on the DFG-out conformation. The lead molecule Asinex-5082 may facilitate the rational design and development of novel selective inhibitors of FGFR3 over VEGFR2 as anticancer drugs.

Iron increases lipid deposition via oxidative stress-mediated mitochondrial dysfunction and the HIF1α-PPARγ pathway.

Iron is an essential micro-element, involved in multiple biological activities in vertebrates. Excess iron accumulation has been identified as an important mediator of lipid deposition. However, the underlying mechanisms remain unknown. In the present study, we found that a high-iron diet significantly increased intestinal iron content and upregulated the mRNA expression of two iron transporters (zip14 and fpn1). Intestinal iron overload increased lipogenesis, reduced lipolysis and promoted oxidative stress and mitochondrial dysfunction. Iron-induced lipid accumulation was mediated by hypoxia-inducible factor-1 α (HIF1α), which was induced in response to mitochondrial oxidative stress following inhibition of prolyl hydroxylase 2 (PHD2). Mechanistically, iron promoted lipid deposition by enhancing the DNA binding capacity of HIF1α to the pparγ and fas promoters. Our results provide experimental evidence that oxidative stress, mitochondrial dysfunction and the HIF1α-PPARγ pathway are critical mediators of iron-induced lipid deposition.

Enhancing Third-Order Nonlinear Optical Property by Regulating Interaction between Zr4(embonate)6 Cage and N, N-Chelated Transition-Metal Cation.

Herein, the combination of anionic Zr4L6 (L = embonate) cages and N, N-chelated transition-metal cations leads to a series of new cage-based architectures, including ion pair structures (PTC-355 and PTC-356), dimer (PTC-357), and 3D frameworks (PTC-358 and PTC-359). Structural analyses show that PTC-358 exhibits a 2-fold interpenetrating framework with a 3,4-connected topology, and PTC-359 shows a 2-fold interpenetrating framework with a 4-connected dia network. Both PTC-358 and PTC-359 can be stable in air and other common solvents at room temperature. The investigations of third-order nonlinear optical (NLO) properties indicate that these materials show different degrees of optical limiting effects. It is surprising that increasing coordination interactions between anion and cation moieties can effectively enhance their third-order NLO properties, which can be attributed to the formation of coordination bonds that facilitate charge transfer. In addition, the phase purity, UV-vis spectra, and photocurrent properties of these materials were also studied. This work provides new ideas for the construction of third-order NLO materials.

Post-Assembly Modification of Homochiral Titanium-Organic Cages for Recognition and Separation of Molecular Isomers.

A chiral metal-organic cage (MOC) was extended and fixed into a porous framework using a post-assembly modification strategy, which made it easier to study the host-guest chemistry of the solid-state MOC using a single-crystal diffraction technique. Anionic Ti4 L6 (L=embonate) cage can be used as a 4-connecting crystal engineering tecton, and its optical resolution was achieved, thus homochiral ΔΔΔΔ- and ΛΛΛΛ-[Ti4 L6 ] cages were obtained. Accordingly, a pair of homochiral cage-based microporous frameworks (PTC-236(Δ) and PTC-236(Λ)) were easily prepared by a post-assembly reaction. PTC-236 has rich recognition sites provided by the Ti4 L6 moieties, chiral channels and high framework stability, affording a single-crystal-to-single-crystal transformation for guest structure analyses. Thus it was successfully utilized for the recognition and separation of isomeric molecules. This study provides a new approach for the orderly combination of well-defined MOCs into functional porous frameworks.

Synthesis, Structure, and Light Absorption Behaviors of Prismatic Titanium-Oxo Clusters Containing Lacunary Lindqvist-like Species.

Exploring new structural types of polyoxotitanium clusters (PTCs), especially those containing classical polyoxometalates structures, has always been the focus of research in the field of metal-oxo clusters. In this work, we present the synthesis and characterization of three prismatic PTCs: namely, Ti8(µ2-O)3(µ4-O)2(OnPr)6(HOnPr)2(L1)8 (PTC-237; H2L1 = 3,5-di-tert-butylcatechol), Ti12(µ2-O)6(µ3-O)8(OnPr)6(L2)12(L3)2 (PTC-238; HL2 = 1-adamantanecarboxylic acid, HL3 = 2-picolinic acid), and [Ti18(µ2-O)4(µ3-O)16(µ5-O)2(OiPr)18(L3)8](L3)2 (PTC-239). Single-crystal X-ray diffraction analyses indicate that the construction of these prismatic PTCs is based on a stepwise interlayer assembly of {Ti3} and {Ti4} substructures. The diameters of their core skeletons are in the range between 0.9 and 1.3 nm. In particular, lacunary Linqvist-like {Ti4} and {Ti5} building units are found to exist in the structures of PTC-237 and PTC-239. According to the solid-state UV-vis diffuse reflectance measurements, the absorption band of 3,5-di-tert-butylcatecholate-functionalized PTC-237 shifts toward the visible-light region, giving a smaller optical band gap of 1.56 eV in comparison to PTC-238 (3.36 eV) and PTC-239 (3.25 eV).

Preparation and Visible-Light Response of Salicylate-Stabilized Heterobimetallic Pb-Ti-Oxo Clusters Initiated via Auxiliary Quaternary Ammonium Salts and a Solvent Effect.

In this study, with the assistance of quaternary ammonium salts we have successfully prepared a new family of salicylate-stabilized heterobimetallic Pb-Ti-oxo clusters, including H(TEA)[Pb2Ti6(µ2-O)2(µ3-O)2(OiPr)4(PA)2(Sal)6(NO3)2] (PTC-321; TEA = tetraethylammonium; HOiPr = isopropanol; H2PA = phenylphosphonic acid; H2Sal = salicylic acid), {PbTi3(µ2-O)(µ3-O)(OiPr)2(PA)(Sal)3(DMF)·CH3CN}n (PTC-322; DMF = dimethylformamide), {PbTi5(µ3-O)6(Sal)3(CH3COO)2(DMF)(OiPr)2}n (PTC-323), [Pb2Ti4(Sal)6(EtO)2(OiPr)6(HOiPr)2]·CH3NH2 (PTC-324; EtOH = CH3CH2OH), H[Pb4Ti9(µ2-O)2(µ3-O)(µ4-O)6(Sal)7(OiPr)13] (PTC-325), and Pb2Ti12(µ2-O)3(µ3-O)3(µ4-O)4(Sal)4(OEt)24 (PTC-326). Single-crystal X-ray diffraction studies demonstrate that the {Ti3Pb(Sal)3} unit acts as the building block to constitute the diverse assembly of PTC-321-PTC-323. Thereinto, the clusters in PTC-322 and PTC-323 are connected into infinite one-dimensional chains. Furthermore, the solvent effects have facilitated the heterobimetallic Pb-Ti-oxo clusters into various configurations in PTC-323-PTC-326. Solid-state ultraviolet-visible spectroscopy analysis indicates that the optical absorption bands of these compounds shift effectively toward the visible-light region, and they were also employed as electrode precursors to investigate their visible-light-driven photocurrent response.

Mitochondria-Dependent Oxidative Stress Mediates ZnO Nanoparticle (ZnO NP)-Induced Mitophagy and Lipotoxicity in Freshwater Teleost Fish.

Due to many special characteristics, zinc oxide nanoparticles (ZnO NPs) are widely used all over the world, leading to their wide distribution in the environment. However, the toxicities and mechanisms of environmental ZnO NP-induced changes of physiological processes and metabolism remain largely unknown. Here, we found that addition of dietary ZnO NPs disturbed hepatic Zn metabolism, increased hepatic Zn and lipid accumulation, downregulated lipolysis, induced oxidative stress, and activated mitophagy; N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN, Zn2+ ions chelator) alleviated high ZnO NP-induced Zn and lipid accumulation, oxidative stress, and mitophagy. Mechanistically, the suppression of mitochondrial oxidative stress attenuated ZnO NP-activated mitophagy and ZnO NP-induced lipotoxicity. Taken together, our study elucidated that mitochondrial oxidative stress mediated ZnO NP-induced mitophagy and lipotoxicity; ZnO NPs could be dissociated to free Zn2+ ions, which partially contributed to ZnO NP-induced changes in oxidative stress, mitophagy, and lipid metabolism. Our study provides novel insights into the impacts and mechanism of ZnO NPs as harmful substances inducing lipotoxicity of aquatic organisms, and accordingly, metabolism-relevant parameters will be useful for the risk assessment of nanoparticle materials in the environment.

["Water-pathogen" theory-based Juanyin Tongluo Recipe for varicocele complicated with oligozoospermia: A clinical observation].

OBJECTIVE: To observe the clinical efficacy of the "water-pathogen" theory-based Juanyin Tongluo Recipe (JTR) in the treatment of varicocele (VC) complicated with oligozoospermia and its effects on the semen parameters, sperm morphology, sperm DNA fragmentation index (DFI) and testis volume of the patient. METHODS: Ninety-two VC patients complicated with oligozoospermia were randomly assigned to receive JTR (n = 47) and Maizhiling Tablets (the control group, n = 45), respectively, both for three months, followed by comparisons of the clinical effects, total sperm count, sperm motility, percentages of progressively motile sperm (PMS) and morphologically normal sperm (MNS), sperm DNA fragmentation index (DFI) and testis volume of the patients before and after medication, and the pregnancy rate after treatment between the two groups. RESULTS: The total rate of effectiveness was significantly higher in the JTR than in the control group (87.23% vs 68.89%, P < 0.05). Compared with the baseline, the patients showed dramatic improvement after treated with JTR in the sperm count (ï¼»16.35 ± 3.52ï¼½ vs ï¼»43.82 ± 6.02ï¼½ ×106, P < 0.05), sperm motility (ï¼»17.37 ± 6.76ï¼½% vs ï¼»36.68 ± 11.32ï¼½%, P < 0.05), PMS (ï¼»13.42 ± 5.62ï¼½% vs ï¼»31.03 ± 7.47ï¼½%, P < 0.05), MNS (ï¼»1.91 ± 0.13ï¼½% vs ï¼»4.06 ± 0.11ï¼½%, P < 0.05), and sperm DFI (ï¼»43.32 ± 7.84ï¼½% vs ï¼»26.98 ± 6.87ï¼½%, P < 0.05), and even better than in the control group (sperm count ï¼»15.78 ± 3.84ï¼½ vs ï¼»31.53 ± 5.62ï¼½ ×106, P < 0.05; sperm motility ï¼»19.41 ± 6.24ï¼½% vs ï¼»31.32 ± 9.73ï¼½%, P < 0.05; PMS ï¼»14.01 ± 4.98ï¼½% vs ï¼»20.71 ± 6.49ï¼½%, P < 0.05; MNS ï¼»1.88 ± 0.14ï¼½% vs ï¼»3.12 ± 0.09ï¼½%, P < 0.05; sperm DFI ï¼»41.42 ± 9.62ï¼½% vs ï¼»34.13 ± 5.73ï¼½%, P < 0.05; sperm DFI, P < 0.05). And the rate of natural pregnancy was significantly higher in the JTR group than in the control (40.43% vs 20%, P < 0.05). No statistically significant difference, however, was observed in the testis volume before and after treatment between the JTR group (ï¼»11.53 ± 1.24ï¼½ vs ï¼»10.89 ± 1.17ï¼½ ml, P > 0.05) and the control (ï¼»10.94 ± 1.34ï¼½ vs ï¼»10.65 ± 1.52ï¼½ ml, P > 0.05). CONCLUSION: Juanyin Tongluo Recipe can increase the total sperm count, sperm motility, percentages of PMS and MNS and sperm DFI, and improve the rate of natural pregnancy in VC patients complicated with oligozoospermia.

[Baihe Yuzi Prescription improves asthenospermia by up-regulating the expression of CFTR in the sperm].

OBJECTIVE: To observe the therapeutic efficacy of Baihe Yuzi Prescription (BYP) in the treatment of clinical syndrome-free asthenospermia and its effects on semen parameters, sperm DNA fragmentation index (DFI) and the expression of the cystic fibrosis transmembrane conductance regulator (CFTR) in the sperm. METHODS: We randomly divided 112 patients with clinical syndrome-free asthenospermia into a control group (n = 55) and an experimental group (n = 57), the former treated orally with L-carnitine liquid combined with vitamin E capsules and the latter with BYP in addition, both for 3 months. After treatment, we obtained the total sperm count, sperm motility, percentages of progressively motile sperm (PMS) and morphologically normal sperm (MNS), sperm DFI and expression of CFTR in the sperm, and compared the above parameters between the two groups of patients before and after medication. RESULTS: The total effectiveness rate was significantly higher in the experimental group (82.46%) than in the control (65.45%) (P < 0.05). Compared with the baseline, the patients in the experimental group showed significant improvement after treatment in the total sperm count (��53.5��3.5�� vs ��86.5��3.9�� ��106, P < 0.05), sperm motility (��23.5��3.5��% vs ��38.8��3.7��%, P < 0.05), PMS (��20.1��3.2��% vs ��30.3��3.3��%, P < 0.05), MNS (��2.3��0.3��% vs ��3.9��0.4��%, P < 0.05), sperm DFI (��37.3��3.1��% vs ��25.2��3.4��%, P < 0.05) and the expression of CFTR (P < 0.05), and even better improvement than the controls in sperm motility (��23.8��3.7��% vs ��30.2��3.4��%, P < 0.05), PMS (��19.6��3.1��% vs ��25.3��2.9��%, P < 0.05), MNS (��2.4��0.4��% vs ��3.1��0.3��%, P < 0.05), and sperm DFI (��36.6��3.3��% vs ��30.3��3.1��%, P < 0.05). The total sperm count and the expression of CFTR, however, were not significantly improved in the control group after treatment (P > 0.05). CONCLUSION: Baihe Yuzi Prescription can increase sperm count and motility, improve sperm morphology and DFI in patients with clinical syndrome-free asthenospermia, which may be related to the up-regulated expression of CFTR in the sperm.

A Water-Soluble Highly Oxidizing Cobalt Molecular Catalyst Designed for Bioinspired Water Oxidation.

Herein, we present a stable water-soluble cobalt complex supported by a dianionic 2,2'-([2,2'-bipyridine]-6,6'-diyl)bis(propan-2-ol) ligand scaffold, which is a rare example of a high-oxidation species, as demonstrated by structural, spectroscopic and theoretical data. Electron paramagnetic resonance (EPR) spectroscopy and magnetic susceptibility measurements revealed that the CoIV center of the mononuclear complex in the solid state resides in the high spin state (sextet, S=5/2). The complex can effectively catalyze water oxidation via a single-site water nucleophilic attack pathway with an overpotential of only 360 mV in a phosphate buffer with a pH of 6. The key intermediate toward water oxidation was speculated based on theoretical calculations and was identified by in situ spectroelectrochemical experiments. The results are important regarding the accessibility of high-oxidation state metal species in synthetic models for achieving robust and reactive oxidation catalysis.

Macrocyclic Inorganic Tin-Containing Oxo Clusters: Heterometallic Strategy for Configuration and Catalytic Activity Modulation.

In this work, the first examples of inorganic macrocyclic tin-oxo clusters which are stabilized by sulfate ligands are reported. As determined by X-ray diffraction and photoelectron spectroscopy analyses, the prepared inorganic Sn10 -oxo cluster displays interesting mixed valence behaviors, with 8 Sn4+ located at the cyclic skeleton and two Sn2+ encapsulated in the center. When further introducing Ti4+ and In3+ ions to the synthetic systems, heterometallic Sn2 Ti6 and SnIn5 Ti6 complexes with Ti6 (SO4 )9 and SnIn5 (SO4 )12 macrocyclic skeletons were prepared whose configuration and packing models were affected by the ionic radius of incorporated metals. Moreover, comparative CO2 reduction experiments confirm that such heterometallic composition can significantly improve the catalytic activities of these inorganic macrocyclic oxo clusters. This work represents a milestone in constructing inorganic tin complexes and also macrocyclic metal oxo clusters with tunable configurations and properties.

Phospholipase C signal mediated the glucose-induced changes of glucose absorption and lipid accumulation in the intestinal epithelial cells of yellow catfish Pelteobagrus fulvidraco.

In present study, we explored the effects and the underlying mechanisms of phospholipase C (PLC) mediating glucose-induced changes in intestinal glucose transport and lipid metabolism by using U-73122 (a PLC inhibitor). We found that glucose incubation activated the PLC signal and U-73122 pre-incubation alleviated the glucose-induced increase in plcb2, plce1 and plcg1 mRNA expression. Meanwhile, U-73122 pre-treatment blunted the glucose-induced increase in sodium/glucose co-transporters 1/2 mRNA and protein expressions. U-73122 pre-treatment alleviated the glucose-induced increase in TAG content, BODIPY 493/503 fluorescence intensity, lipogenic enzymes (glucose 6-phospate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), malic enzyme and fatty acid synthase (FAS)) activity and the mRNA expressions of lipogenic genes and related transcription factors (6pgd, g6pd, fas, acca, srebp1 and carbohydrate response element-binding protein (chrebp)) in intestinal epithelial cells of yellow catfish. Further research found that U-73122 pre-incubation mitigated the glucose-induced increase in the ChREBP protein expression and the acetylation level of ChREBP in HEK293T cells. Taken together, these data demonstrated that the PLC played a major role in the glucose-induced changes of glucose transport and lipid metabolism and provide a new perspective for revealing the molecular mechanism of glucose-induced changes of intestinal glucose absorption, lipid deposition and metabolism.

Coordination Assembly of Tetrahedral Zr4(embonate)6 Cages with Eu3+ Ions.

Herein we systematically investigated the coordination assembly behavior of Zr4L6 cages with Eu3+ ions at room temperature. Through adjustment of the concentration of Eu salt and changes of the type and molar ratio of the solvent, a series of Zr4L6-Eu structures with different structure dimensionalities have been synthesized and structurally characterized. In addition, we also studied the optical properties of these materials in detail, including the fluorescent and third-order nonlinear-optical properties. Most notably, a 2D layer structure with a strong aromatic π···π-stacking force exhibits a good optical-limiting effect.

Lipophagy mediated carbohydrate-induced changes of lipid metabolism via oxidative stress, endoplasmic reticulum (ER) stress and ChREBP/PPARγ pathways.

High-carbohydrate diets (HCD) can induce the occurrence of nonalcoholic fatty liver disease (NAFLD), characterized by dramatic accumulation of hepatic lipid droplets (LDs). However, the potential molecular mechanisms are still largely unknown. In this study, we investigated the role of autophagy in the process of HCD-induced changes of hepatic lipid metabolism, and to examine the process of underlying mechanisms during these molecular contexts. We found that HCD significantly increased hepatic lipid accumulation and activated autophagy. Using primary hepatocytes, we found that HG increased lipid accumulation and stimulated the release of NEFA by autophagy-mediated lipophagy, and that lipophagy significantly alleviated high glucose (HG)-induced lipid accumulation. Oxidative and endoplasmic reticulum (ER) stress pathways played crucial regulatory roles in HG-induced lipophagy activation and HG-induced changes of lipid metabolism. Further investigation found that HG-activated lipophagy and HG-induced changes of lipid metabolism were via enhancing carbohydrate response element-binding protein (ChREBP) DNA binding capacity at PPARγ promoter region, which in turn induced transcriptional activation of the key genes related to lipogenesis and autophagy. The present study, for the first time, revealed the novel mechanism for lipophagy mediating HCD-induced changes of lipid metabolism by oxidative stress and ER stress, and ChREBP/PPARγ pathways. Our study provided innovative evidence for the direct relationship between carbohydrate and lipid metabolism via ChREBP/PPARγ pathway.

Dietary Nano-ZnO Is Absorbed via Endocytosis and ZIP Pathways, Upregulates Lipogenesis, and Induces Lipotoxicity in the Intestine of Yellow Catfish.

Nano-sized zinc oxide (nano-ZnO) affects lipid deposition, but its absorption patterns and mechanisms affecting lipid metabolism are still unclear. This study was undertaken to investigate the molecular mechanism of nano-ZnO absorption and its effects on lipid metabolism in the intestinal tissues of a widely distributed freshwater teleost yellow catfish Pelteobagrus fulvidraco. We found that 100 mg/kg dietary nano-ZnO (H-Zn group) significantly increased intestinal Zn contents. The zip6 and zip10 mRNA expression levels were higher in the H-Zn group than those in the control (0 mg/kg nano-ZnO), and zip4 mRNA abundances were higher in the control than those in the L-Zn (50 mg/kg nano-ZnO) and H-Zn groups. Eps15, dynamin1, dynamin2, caveolin1, and caveolin2 mRNA expression levels tended to reduce with dietary nano-ZnO addition. Dietary nano-ZnO increased triglyceride (TG) content and the activities of the lipogenic enzymes glucose 6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), and isocitrate dehydrogenase (ICDH), upregulated the mRNA abundances of lipogenic genes 6pgd, fatty acid synthase (fas), and sterol regulatory element binding protein 1 (srebp1), and reduced the mRNA expression of farnesoid X receptor (fxr) and small heterodimer partner (shp). The SHP protein level in the H-Zn group was lower than that in the control and the L-Zn group markedly. Our in vitro study indicated that the intestinal epithelial cells (IECs) absorbed nano-ZnO via endocytosis, and nano-Zn-induced TG deposition and lipogenesis were partially attributable to the endocytosis of nano-ZnO in IECs. Mechanistically, nano-ZnO-induced TG deposition was closely related to the metal responsive transcription factor 1 (MTF-1)-SHP pathway. Thus, for the first time, we found that the lipogenesis effects of nano-ZnO probably depended on the key gene shp, which is potentially regulated by MTF1 and/or FXR. This novel signaling pathway of MTF-1 through SHP may be relevant to explain the toxic effects and lipotoxicity ascribed to dietary nano-ZnO addition.

Combining a Titanium-Organic Cage and a Hydrogen-Bonded Organic Cage for Highly Effective Third-Order Nonlinear Optics.

Many metal-organic cages (MOCs) and a few hydrogen-bonded organic cages (HOCs) have been investigated, but little is reported about cooperative self-assembly of MOCs and HOCs. Herein, we describe an unprecedented MOC&HOC co-crystal composed of tetrahedral Ti4 L6 (L=embonate) cages and in-situ-generated [(NH3 )4 (TIPA)4 ] (TIPA=tris(4-(1H-1,2,4-triazol-1-yl)phenyl)amine) cages. Chiral transfer is observed from the enantiopure Ti4 L6 cage to enantiopure [(NH3 )4 (TIPA)4 ] cage. Two homochiral supramolecular frameworks with opposite handedness (PTC-235(Δ) and PTC-235(Λ)) are formed. Such MOC&HOC co-crystal features high stability in water and other solvents, affording single-crystal-to-single-crystal transformation to trap CH3 CN molecules and identify disordered NH4 + cations. A tablet pressing method is developed to test the third-order nonlinear optical property of KBr-based PTC-235 thin film. Such a thin film exhibits an excellent optical limiting effect.

Dietary Glucose Increases Glucose Absorption and Lipid Deposition via SGLT1/2 Signaling and Acetylated ChREBP in the Intestine and Isolated Intestinal Epithelial Cells of Yellow Catfish.

BACKGROUND: Dietary carbohydrate affects intestinal glucose absorption and lipid deposition, but the underlying mechanisms are unknown. OBJECTIVES: We used yellow catfish and their isolated intestinal epithelial cells (IECs) to test the hypothesis that sodium/glucose cotransporters (SGLTs) 1/2 and acetylated carbohydrate response element binding protein (ChREBP) mediated glucose-induced changes in glucose absorption and lipid metabolism. METHODS: Yellow catfish (mean ± SEM weight: 4.68 ± 0.02 g, 3 mo old, mixed sex) were fed diets containing 250 g carbohydrates/kg from glucose (G, control), corn starch (CS), sucrose (S), potato starch (PS), or dextrin (D) for 10 wk. IECs were isolated from different yellow catfish and incubated for 24 h in a control or glucose (15 mM) solution with or without a 2-h pretreatment with an inhibitor [sotagliflozin (LX-4211) or tubastatin A (TBSA)]. Human embryonic kidney cells (HEK293T cells) were transfected with a Flag-ChREBP plasmid to explore ChREBP acetylation. Triglyceride (TG) and glucose concentrations and enzymatic activities were measured in the intestine and IECs of yellow catfish. They also were subjected to immunofluorescence, immunoprecipitation, qPCR, and immunoblotting. Immunoblotting and immunoprecipitation were performed with HEK293T cells. RESULTS: The G group had greater intestine TGs (0.99- to 2.30-fold); activities of glucose 6-phospate dehydrogenase, 6-phosphogluconate dehydrogenase, and isocitrate dehydrogenase (0.12- to 2.10-fold); and expression of lipogenic genes (0.32- to 2.34-fold) than the CS, PS, and D groups. The G group had greater intestine sglt1/2 mRNA and protein expression than the CS, S and D groups (0.35- to 1.12-fold and 0.40- to 4.67-fold, respectively), but lower mRNA amounts of lipolytic genes (48.6%-65.8%) than the CS and PS groups. LX-4211 alleviated the glucose-induced increase in sglt1/2 mRNA (38.2%-47.4%) and SGLT1 protein (48.0%) expression, TGs (29.3%), and lipogenic enzyme activities (27.7%-42.1%) and gene expression (38.0%-55.5%) in the IECs. TBSA promoted the glucose-induced increase in TGs (11.3%), fatty acid synthase activity (32.6%), and lipogenic gene expression (21.6%-34.4%) in the IECs and acetylated ChREBP (10.5%) in HEK293T cells. CONCLUSIONS: SGLT1/2 signaling and acetylated ChREBP mediated glucose-induced changes in glucose absorption and lipid metabolism in the intestine and IECs of yellow catfish.

FXR-mediated inhibition of autophagy contributes to FA-induced TG accumulation and accordingly reduces FA-induced lipotoxicity.

BACKGROUND: Excessive dietary fat intake induces lipid deposition and contributes to the progress of nonalcoholic fatty liver disease (NAFLD). However, the underlying mechanisms are still unclear. METHODS: Yellow catfish were given two experimental diets with dietary lipid levels of 11.3 and 15.4%, respectively, for 56 days, and the contents of triglyceride (TG), nonesterified free fatty acids (NEFA) and bile acid (BA), RNA-seq, enzymatic activities and mRNA expression were deteremined in the liver tissues. Hepatocytes from yellow catfish liver tissues were isolated and cultured. Fatty acids (FA) (palmitic acid: OA, oleic acid =1:1), pathway inhibitors (MA, autophagy inhibitor; guggulsterone, FXR inhibitor) and agonist (rapamyicn, autophagy agonist; GW4064, FXR agonist) were used to incubate the cells. TG and NEFA contents, ultrastructural observation, autophagic vesicles and intracellular LD,apoptosis,western blot and Co-IP, and Immunofluorescence analysis, enzymatic activities and Q-PCR were decided. RESULTS: Using RNA sequencing, we found that high fat diets induced changes in expression of many genes associated with the pathways of lipid metabolism and autophagy. The mRNA profiles of the differentially expressed genes (DEG) indicated that high dietary fat-induced lipid deposition was predominantly influenced by the inhibition of autophagy. Using primary hepatocytes, we found that fatty acids (FA) suppressed autophagy, which in turn reduced cellular free FA level by decreasing triglyceride (TG) breakdown. Moreover, our study indicated that farnesoid X receptor (FXR)-cyclic AMP-responsive element-binding protein (CREB) axis was the pivotal physiological switch regulating FA-induced changes of autophagy and lipid metabolism, which represented cellular defenses against FA-induced lipotoxicity. CONCLUSION: This discovery may provide new targets for treating pathological changes involved in the dysfunction of autophagy and metabolism, including NAFLD. Video Abstract.

Ti4(embonate)6 Cage-Ligand Strategy on the Construction of Metal-Organic Frameworks with High Stability and Gas Sorption Properties.

Herein we report an efficient strategy to construct cage-based metal-organic frameworks (MOFs) via the assembly of Ti4L6 (L = embonate) cages and N-contained ligands with Mn2+ and Zn2+ ions, respectively, and two Ti4L6-cage-based MOFs (PTC-219 and PTC-220) with high stability and gas sorption properties have been generated through two-step reactions, respectively.

Self-Assembly of a Ti4(embonate)6 Cage toward Silver.

Herein we report a variety of supramolecular architectures that are self-assembled by the highly charged anionic Ti4L6 (L = embonate) cages and noble-metal Ag+ ions in the presence of the different ligands, including six Ti4L6-Ag(PPh3) cages in whose structures the Ti4L6 cage catches various in situ formed [Ag(PPh3)]+ moieties by a coordination bond and one cocrystal superstructure of a Ti4L6 cage with an in situ generated [Ag2(Ph2P(CH2)5PPh2)3]2+ cage via supramolecular interactions. In addition, the third-order nonlinear-optical properties of these compounds are investigated in detail.