Water and Cu+ Synergy in Selective CO2 Hydrogenation to Methanol over Cu-MgO-Al2O3 Catalysts.

The CO2 hydrogenation reaction to produce methanol holds great significance as it contributes to achieving a CO2-neutral economy. Previous research identified isolated Cu+ species doping the oxide surface of a Cu-MgO-Al2O3-mixed oxide derived from a hydrotalcite precursor as the active site in CO2 hydrogenation, stabilizing monodentate formate species as a crucial intermediate in methanol synthesis. In this work, we present a molecular-level understanding of how surface water and hydroxyl groups play a crucial role in facilitating spontaneous CO2 activation at Cu+ sites and the formation of monodentate formate species. Computational evidence has been experimentally validated by comparing the catalytic performance of the Cu-MgO-Al2O3 catalyst with hydroxyl groups against that of its hydrophobic counterpart, where hydroxyl groups are blocked using an esterification method. Our work highlights the synergistic effect between doped Cu+ ions and adjacent hydroxyl groups, both of which serve as key parameters in regulating methanol production via CO2 hydrogenation. By elucidating the specific roles of these components, we contribute to advancing our understanding of the underlying mechanisms and provide valuable insights for optimizing methanol synthesis processes.

Oridonin attenuates liver ischemia-reperfusion injury by suppressing PKM2/NLRP3-mediated macrophage pyroptosis.

BACKGROUND: The NOD-like receptor protein 3 (NLRP3) mediated pyroptosis of macrophages is closely associated with liver ischemia reperfusion injury (IRI). As a covalent inhibitor of NLRP3, Oridonin (Ori), has strong anti-inflammasome effect, but its effect and mechanisms for liver IRI are still unknown. METHODS: Mice and liver macrophages were treated with Ori, respectively. Co-IP and LC-MS/MS analysis of the interaction between PKM2 and NLRP3 in macrophages. Liver damage was detected using H&E staining. Pyroptosis was detected by WB, TEM, and ELISA. RESULTS: Ori ameliorated liver macrophage pyroptosis and liver IRI. Mechanistically, Ori inhibited the interaction between pyruvate kinase M2 isoform (PKM2) and NLRP3 in hypoxia/reoxygenation（H/R）-induced macrophages, while the inhibition of PKM2/NLRP3 reduced liver macrophage pyroptosis and liver IRI. CONCLUSION: Ori exerted protective effects on liver IRI via suppressing PKM2/NLRP3-mediated liver macrophage pyroptosis, which might become a potential therapeutic target in the clinic.

A comprehensive review of medium chain monoglycerides on metabolic pathways, nutritional and functional properties, nanotechnology formulations and applications in food system.

A large and growing body of literature has investigated the broad antibacterial spectrum and strong synergistic antimicrobial activity of medium chain monoglycerides (MCMs) have been widely investigated. Recently, more and more researches have focused on the regulation of MCMs on metabolic health and gut microbiota both in vivo and in vitro. The current review summarizes the digestion, absorption and metabolism of MCMs. Subsequently, it focuses on the functional and nutritional properties of MCMs, including the antibacterial and antiviral characteristics, the modulation of metabolic balance, the regulation of gut microbiota, and the improvement in intestinal health. Additionally, we discuss the most recent developments and application of MCMs using nanotechnologies in food industry, poultry and pharmaceutical industry. Additionally, we analyze recent application examples of MCMs and their nanotechnology formation used in food. The development of nanotechnology platforms facilitating molecular encapsulation and functional presentation contribute to the application of hydrophobic fatty acids and monoglycerides in food preservation and their antibacterial effectiveness. This study emphasizes the metabolic mechanisms and biological activity of MCMs by summarizing the prevailing state of knowledge on this topic, as well as providing insights into prospective techniques for developing the beneficial applications of MCMs to realize the industrialized production.

miR-449a ameliorates acute rejection after liver transplantation via targeting procollagen-lysine1,2-oxoglutarate5-dioxygenase 1 in macrophages.

Acute rejection (AR) is an important factor that leads to poor prognosis after liver transplantation (LT). Macrophage M1-polarization is an important mechanism in AR development. MicroRNAs play vital roles in disease regulation; however, their effects on macrophages and AR remain unclear. In this study, rat models of AR were established following LT, and macrophages and peripheral blood mononuclear cells were isolated from rats and humans, respectively. We found miR-449a expression to be significantly reduced in macrophages and peripheral blood mononuclear cells. Overexpression of miR-449a not only inhibited the M1-polarization of macrophages in vitro but also improved the AR of transplant in vivo. The mechanism involved inhibiting the noncanonical nuclear factor-kappaB (NF-κB) pathway. We identified procollagen-lysine1,2-oxoglutarate5-dioxygenase 1 (PLOD1) as a target gene of miR-449a, which could reverse miR-449a's inhibition of macrophage M1-polarization, amelioration of AR, and inhibition of the NF-κB pathway. Overall, miR-449a inhibited the NF-κB pathway in macrophages through PLOD1 and also inhibited the M1-polarization of macrophages, thus attenuating AR after LT. In conclusion, miR-449a and PLOD1 may be new targets for the prevention and mitigation of AR.

The feasibility of quantitative assessment of dynamic 18F-fluorodeoxyglucose PET in Takayasu's arteritis: a pilot study.

PURPOSE: PET has been demonstrated to be sensitive for detecting active inflammation in Takayasu's arteritis (TAK) patients, but semi-quantitative-based assessment may be susceptible to various biological and technical factors. Absolute quantification via dynamic PET (dPET) may provide a more reliable and quantitative assessment of TAK-active arteries. The purpose of this study was to investigate the feasibility and efficacy of dPET in quantifying TAK-active arteries compared to static PET. MATERIALS AND METHODS: This prospective study enrolled 10 TAK-active patients (fulfilled the NIH criteria) and 5 control participants from March to October 2022. One-hour dPET scan (all TAK and control participants) and delayed static PET scan at 2-h (all TAK patients) were acquired. For 1-h static PET, summed images from 50 to 60 min of the dPET were extracted. PET parameters derived from 1- and 2-h static PET including SUV (SUV1H and SUV2H), target-to-background ratio (TBR) (TBR1H and TBR2H), net influx rate (Ki), and TBRKi extracted from dPET were obtained. The detectability of TAK-active arteries was compared among different scanning methods using the generalized estimating equation (GEE) with a logistic regression with repeated measures, and the GEE with gamma distribution and log link function was used to evaluate the different study groups or scanning methods. RESULTS: Based on the disease states, 5 cases of TAK were classified as untreated and relapsed, respectively. The SUVmax on 2-h PET was higher than that on 1-h PET in the untreated patients (P < 0.05). However, no significant differences were observed in the median SUVmax between 1-h PET and 2-h PET in the relapsed patients (P > 0.05). The TBRKi was significantly higher than both TBR1H and TBR2H (all P < 0.001). Moreover, the detectability of TAK-active arteries by dPET-derived Ki was significantly higher than 1-h and 2-h PET (all P < 0.001). Significant differences were observed in Kimax, SUVmax-1H, TBR1H, and TBRKi among untreated, relapsed, and control groups (all P < 0.05). CONCLUSIONS: Absolute quantitative assessment by dPET provides an improved sensitivity and detectability in both visualization and quantification of TAK-active arteries. This elucidates the clinical significance of dPET in the early detection of active inflammation and monitoring recurrence.

HSP110 aggravates ischemia-reperfusion injury after liver transplantation by promoting NF-κB pathway.

BACKGROUND: Ischemia-reperfusion injury (IRI) poses a significant challenge to liver transplantation (LT). The underlying mechanism primarily involves overactivation of the immune system. Heat shock protein 110 (HSP110) functions as a molecular chaperone that helps stabilize protein structures. METHODS: An IRI model was established by performing LT on Sprague-Dawley rats, and HSP110 was silenced using siRNA. Hematoxylin-eosin staining, TUNEL, immunohistochemistry, ELISA and liver enzyme analysis were performed to assess IRI following LT. Western blotting and quantitative reverse transcription-polymerase chain reaction were conducted to investigate the pertinent molecular changes. RESULTS: Our findings revealed a significant increase in the expression of HSP110 at both the mRNA and protein levels in the rat liver following LT (P < 0.05). However, when rats were injected with siRNA-HSP110, IRI subsequent to LT was notably reduced (P < 0.05). Additionally, the levels of liver enzymes and inflammatory chemokines in rat serum were significantly reduced (P < 0.05). Silencing HSP110 with siRNA resulted in a marked decrease in M1-type polarization of Kupffer cells in the liver and downregulated the NF-κB pathway in the liver (P < 0.05). CONCLUSIONS: HSP110 in the liver promotes IRI after LT in rats by activating the NF-κB pathway and inducing M1-type polarization of Kupffer cells. Targeting HSP110 to prevent IRI after LT may represent a promising new approach for the treatment of LT-associated IRI.

Untargeted Lipidomics Method for the Discrimination of Five Crab Species by Ultra-High-Performance Liquid Chromatography High-Resolution Mass Spectrometry Combined with Chemometrics.

In this study, ultra-high-performance liquid chromatography high-resolution accurate mass-mass spectrometry (UHPLC-HRAM/MS) was applied to characterize the lipid profiles of five crab species. A total of 203 lipid molecular species in muscle tissue and 176 in edible viscera were quantified. The results indicate that Cancer pagurus contained high levels of lipids with a docosahexaenoic acid (DHA) and eicosapntemacnioc acid (EPA) structure in the muscle tissue and edible viscera. A partial least squares discriminant analysis (PLS-DA) showed that PE 16:0/22:6, PE P-18:0/20:5, PA 16:0/22:6 and PC 16:0/16:1 could be used as potential biomarkers to discriminate the five kinds of crabs. In addition, some lipids, such as PE 18:0/20:5, PC 16:0/16:1, PE P-18:0/22:6 and SM 12:1;2O/20:0, could be used as characteristic molecules to distinguish between Cancer magister and Cancer pagurus, which are similar in appearance. This study provides a new perspective on discriminating crab species from MS-based lipidomics.

Discrimination of chrysanthemum varieties using lipidomics based on UHPLC-HR-AM/MS/MS.

BACKGROUND: Chrysanthemum is one of the most important and popular ornamentals over the world. Chrysanthemum drink is a type of traditional healthy drink like Chinese tea. Owing to the differences in the chemical compositions, different chrysanthemum varieties have different medicinal effects on human health. Thus, the identification of different chrysanthemum varieties is very important and necessary. This study aims to distinguish seven chrysanthemum varieties that are widely used in China. First, total lipids were obtained from chrysanthemums. After that, lipid profiles were characterized using ultra-high-performance liquid chromatography hyphenated with a Q Exactive™ high resolution-accurate-mass mass spectrometer. RESULTS: A total of 163 lipid molecular species from 17 types of lipid classes in seven varieties of chrysanthemums were determined. Principal component analysis indicated that three lipid molecules, lysophosphatidylethanolamine(18:2) (LPE(18:2)), LPE(16:0), and phosphatidic acid(18:2/18:3) (variable importance in projection >3, P < 0.001), can be used as potential biomarkers to distinguish seven chrysanthemum varieties. Hierarchical cluster analysis showed that the lipid molecular profiles of 'Gongju' were most similar to 'Jinzijianju', followed by 'Huaibaiju', 'Boju', 'Hangbaiju', 'Chuju', and 'Fubaiju'. CONCLUSION: This comprehensive analysis provided a new method to identify chrysanthemum varieties through the perspective of lipidomics combined with chemometrics. © 2022 Society of Chemical Industry.

Cytotoxic and Pro-Apoptotic Effects of Leaves Extract of Antiaris africana Engler (Moraceae).

Antiaris africana Engler leaves have been used in Senegalese folk medicine to treat breast cancer. The present study aimed to investigate the anticancer potential of Antiaris africana Engler leaves using several human cancer cell lines. The leaves of Antiaris africana Engler were extracted in parallel with water or 70% ethanol and each extract divided into three parts by successive liquid-liquid extraction with ethyl acetate and butanol. The phytochemical components of the active extract were investigated using ultra-performance liquid chromatography-diode array detector-quadrupole time-of-flight tandem mass spectrometry (UPLC-DAD-QTOF-MS/MS). The cytotoxic and cytostatic effects of each extract, as well as their fractions, were evaluated in vitro via flow and image cytometry on different human cancer phenotypes, such as breast (MCF-7), pancreas (AsPC-1), colon (SW-620) and acute monocytic leukemia (THP-1). Both hydro-alcoholic and aqueous extracts induced strong apoptosis in MCF-7 cells. The water fraction of the hydro-alcoholic extract was found to be the most active, suppressing the cell growth of MCF-7 in a dose-dependent manner. The half maximum effective concentration (EC50) of this fraction was 64.6 ± 13.7 µg/mL for MCF-7, with equivalent values for all tested phenotypes. In parallel, the apoptotic induction by this fraction resulted in a EC50 of 63.5 ± 1.8 µg/mL for MCF-7, with again equivalent values for all other cellular tested phenotypes. Analysis of this fraction by UPLC-DAD-QTOF-MS/MS led to the identification of hydroxycinnamates as major components, one rutin isomer, and three cardiac glycosides previously isolated from seeds and bark of Antiaris africana Engler and described as cytotoxic in human cancer models. These results provide supportive data for the use of Antiaris africana Engler leaves in Senegal.

Cannabis sativa Extract Induces Apoptosis in Human Pancreatic 3D Cancer Models: Importance of Major Antioxidant Molecules Present Therein.

In recent years, interest in Cannabis sativa L. has been rising, as legislation is moving in the right direction. This plant has been known and used for thousands of years for its many active ingredients that lead to various therapeutic effects (pain management, anti-inflammatory, antioxidant, etc.). In this report, our objective was to optimize a method for the extraction of cannabinoids from a clone of Cannabis sativa L. #138 resulting from an agronomic test (LaFleur, Angers, FR). Thus, we wished to identify compounds with anticancer activity on human pancreatic tumor cell lines. Three static maceration procedures, with different extraction parameters, were compared based on their median inhibitory concentration (IC50) values and cannabinoid extraction yield. As CBD emerged as the molecule responsible for inducing apoptosis in the human pancreatic cancer cell line, a CBD-rich cannabis strain remains attractive for therapeutic applications. Additionally, while gemcitabine, a gold standard drug in the treatment of pancreatic cancer, only triggers cell cycle arrest in G0/G1, CBD also activates the cell signaling cascade to lead to programmed cell death. Our results emphasize the potential of natural products issued from medicinal hemp for pancreatic cancer therapy, as they lead to an accumulation of intracellular superoxide ions, affect the mitochondrial membrane potential, induce G1 cell cycle arrest, and ultimately drive the pancreatic cancer cell to lethal apoptosis.

Probiotics-fermented blueberry juices as potential antidiabetic product: antioxidant, antimicrobial and antidiabetic potentials.

BACKGROUND: Fermentation is a traditional food-preserving technique. It is an effective process, widely used to enrich the nutrients diversity and bioactivity of the fermented foods since ancient times. This study aimed at investigating the effects of various fermentation starters on the physicochemical, antioxidant, antimicrobial, and antidiabetic properties of blueberry juices. The blueberry juices were fermented by natural fermentation (NFBJ), self-made starters fermentation (SFBJ), and commercial starters fermentation (CFBJ); fresh blueberry juice (BBJ) was processed without fermentation for comparison. RESULTS: Probiotics-fermented blueberry juices (SFBJ and CFBJ) showed less total and reducing sugars, higher titratable acidity, and a wider variety and higher amounts of organic acids than non-fermented blueberry juice (BBJ) did. All the fermented blueberry juices (NFBJ, SFBJ, and CFBJ) showed significantly (P < 0.05) higher antioxidant potentials than that of BBJ measured by 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid, cupric-reducing antioxidant capacity, and ferric-reducing ability power assays. The SFBJ exhibited the highest antibacterial activities against Escherichia coli, Staphylococcus aureus, and Salmonella Typhimurium, with inhibition zone diameters of 38.84 ± 1.74 mm, 34.91 ± 1.53 mm, and 36.18 ± 3.16 mm respectively. Compared with BBJ, the α-glucosidase inhibitory activity of the SFBJ and CFBJ increased by two-to threefold. The α-amylase inhibitory activity of the SFBJ and CFBJ increased by 600%, whereas the spontaneous fermentation showed no improvement. The SFBJ and CFBJ promoted glucose consumption of HepG2 cell lines, indicating the promising potential for a higher glucose bio-utilization. CONCLUSIONS: The SFBJ and CFBJ showed remarkable improvements in the antioxidant, antimicrobial, and antidiabetic activities compared with non-fermented and spontaneous fermented juices, indicating their promising potentials as an antihyperglycemic agent. © 2021 Society of Chemical Industry.

The Role of the AIMP1 Pathway in Diabetic Retinopathy: AIMP1-Targeted Intervention Study in Diabetic Retinopathy.

INTRODUCTION: We characterized the role of aminoacyl-tRNA synthetase-interacting multifunctional protein 1 (AIMP1) in retinal inflammation and apoptosis regulation, both in vivo and in vitro. In addition, we used clinical specimens to show the relationship between AIMP1 and the development of diabetic retinopathy (DR). OBJECTIVE: To elucidate the role of AIMP1 in DR. METHODS: A diabetic AIMP1-specific knockout (KO) C57 mouse model was used. Human retinal microvascular endothelial cells (HRMECs) were incubated with normal glucose, high glucose (HG), and HG + AIMP1-small interfering RNA (siRNA). The expression of AIMP1 and relative inflammatory and apoptotic cytokines in diabetic mice retina and HRMECs were measured using Western blotting and polymerase chain reaction. The apoptosis of HRMECs was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The levels of AIMP1 in the vitreous humor and serum were determined using ELISA. Possible correlations between the intravitreal level of AIMP1 and blood glucose, glycosylated hemoglobin HbA1c, intravitreal levels of IL-1ß, and caspase-3 were determined. RESULTS: The expression of inflammatory and apoptotic proteins was inhibited in the AIMP1 KO mice and HRMECs incubated with AIMP1-siRNA. The apoptosis of HRMECs was decreased in the AIMP1-siRNA group. The intravitreal level of AIMP1 in DR patients was significantly higher than that in nondiabetic patients (p < 0.01). There was a positive correlation between intravitreal AIMP1 and HbA1c and intravitreal IL-1ß and caspase-3 (p < 0.05). CONCLUSIONS: HG induced increased expression of AIMP1 in HRMECs and retinas from diabetic C57 mice, thereby increasing the expression of inflammatory and apoptotic cytokines, which promoted DR progression. A decrease in AIMP1 expression prevented the development of DR by inhibiting the activation of inflammatory and apoptotic signaling. Therefore, AIMP1 is an effective interfering target for the prevention and treatment of DR.

Effects of increasing alfalfa (Medicago sativa) leaf levels on the fattening and slaughtering performance of organic broilers.

A feeding trial was conducted to evaluate the effects of increasing alfalfa leaf levels on the performance of organic broilers. The impact of drying temperature on the nutritional value of alfalfa leaves and thereby on broiler performance was studied using alfalfa leaves dried at either low (alfalfa leaves low temperature (ALLT)) or high temperatures (alfalfa leaves (AL)). Six hundred male Hubbard JA-757 broilers were divided into five feeding groups (Control (C), AL2, AL3, AL4 and ALLT5). Alfalfa leaf content was increased in each of the three fattening phases by 5% (C: 0%-0%-0%; AL2: 0%-5%-10%; AL3: 5%-10%-15%; AL4: 10%-15%-20%; and ALLT5: 10%-15%-20%). At the end of the experiment, broilers in group C had the highest body and carcass weights. Groups AL3, AL4 and ALLT5 showed the lowest body and carcass weights. In particular, the early introduction of alfalfa leaves (5% in phase 1) and high alfalfa leaf content (15%-20%) significantly decreased performance. Antinutritional substances such as saponins occur in alfalfa. In fact, the saponin analysis showed high contents of 3-Glc-Glc-28-Ara-Rha-medicagenic acid and HexA-dHex-Pen-Pen-Pen-zanhic acid in both high- and low-temperature alfalfa leaves.

In vitro and in vivo investigations of probiotic properties of lactic acid bacteria isolated from Chinese traditional sourdough.

A total of 88 lactic acid bacteria (LAB) strains were isolated from Chinese traditional sourdough and five of them were selected based on their bile resistance. All the five strains were identified as Lactobacillus plantarum by 16S rRNA gene sequencing. In vitro probiotic properties of the L. plantarum strains including tolerance to simulated gastrointestinal conditions, aggregation activity, and cholesterol removal ability were assessed. Two representatives, L. plantarum ZJUFT34 and L. plantarum ZJUFT17, were intragastrically administered to male C57BL/6J mice of 4-week age for 6 weeks to evaluate their in vivo health-promoting effects. The results indicated that L. plantarum ZJUFT34, L. plantarum ZJUFHN9, and L. plantarum ZJUFAH5 could survive the 3-h incubation in simulated gastric juice with a pH value of 2.0, while L. plantarum ZJUFT32 and L. plantarum ZJUFT17 exhibited better autoaggregation activities and coaggregation activities with pathogens. All the strains showed a cholesterol removal ability in vitro. However, L. plantarum ZJUFT34 or L. plantarum ZJUFT17 administration did not significantly change the serum total cholesterol in vivo. But the ratio of high-density lipoprotein cholesterol to low-density lipoprotein cholesterol was significantly increased by the L. plantarum administration. Besides, L. plantarum ZJUFT17 significantly lowered serum tumor necrosis factor (TNF)-α concentrations. Furthermore, the administration of the LAB strains showed significant influences on lipid metabolism-related gut microbiota. These findings suggested that the L. plantarum strains may benefit the prevention of metabolic syndrome.

Dietary glycerol monolaurate supplementation for the modification of functional properties of egg white protein.

BACKGROUND: Understanding the interactions between feed additives and the functional properties of egg white protein (EWP) may offer novel insights into the effects of feed additives on laying hens and may provide an alternative for modification of the functional properties of EWP by using laying hens as bioreactors. Glycerol monolaurate (GML) is widely used in the food industry as an effective antibacterial emulsifier. In this work, the effects of three doses of dietary GML supplementation (150, 300, and 450 mg kg-1 hen) on the functional properties of EWP were investigated. RESULTS: The hardness of EWP gels was significantly improved by 300 and 450 mg kg-1 GML supplementation. Foaming capacity (FC) and foaming stability (FS) were increased after GML treatment; 450 mg kg-1 GML supplementation showed the most significant improvements, with 44.82% in FC and 23.39% in FS. Stabilization of EWP-oil emulsions was also improved, supported by a slowed creaming process and the formation of smaller oil droplets. The heat denaturation temperature and rheological properties were also modified by dietary GML supplementation, implying improved thermal stability. CONCLUSION: Our study demonstrated that GML supplementation has the potential to modify the functional properties of EWP, broadening the application of GML and providing a new perspective for evaluation of the efficacy of feed additives. © 2019 Society of Chemical Industry.

Change of ranibizumab-induced human vitreous protein profile in patients with proliferative diabetic retinopathy based on proteomics analysis.

BACKGROUND: Preoperative treatment of anti-vascular endothelial growth factor (VEGF) agents is extensively used in proliferative diabetic retinopathy (PDR), but the molecular mechanism is not fully understood. The objective of this research is to observe change of protein profile induced by ranibizumab (an anti-VEGF agent) in vitreous humor from PDR patients and reveal the effects of anti-VEGF treatment on PDR. METHODS: A proteomic method was used to identify differentially expressed proteins in vitreous humor. Untreated PDR patients were defined as PDR group, while those who treated with intravitreal injection of ranibizumab (IVR) were defined as IVR. Gene Ontology (GO) annotation and REACTOME pathways were obtained from DAVID Bioinformatics Resources. Intravitreal level of apolipoprotein C-I (APOC1), serpin peptidase inhibitor clade A member 5 (SERPINA5), tissue inhibitor of metalloproteinases (TIMP2), and keratin 1 (KRT1) were determined by enzyme-linked immuno sorbent assay (ELISA). RESULTS: 339 differentially expressed proteins were identified in response to IVR. The most notable GO annotation describes the altered proteins was "innate immune response". The most notable REACTOME pathway was "platelet degranulation". ELISA result showed increased level of APOC1, SERPINA5, KRT1 and a decreased level of TIMP2 in PDR group compared with IVR. CONCLUSIONS: In addition to decreasing VEGF level, ranibizumab is associated with change of human vitreous protein profile in patients with PDR, in which the differential proteins are involved in immune response, platelet degranulation, complement activation etc., suggesting that the effects of VEGF are involved in these signaling pathways.

Activation of the TXNIP/NLRP3 inflammasome pathway contributes to inflammation in diabetic retinopathy: a novel inhibitory effect of minocycline.

OBJECTIVE AND DESIGN: Chronic low-grade inflammation occurs in diabetic retinopathy (DR), but the underlying mechanism(s) remains (remain) unclear. NLRP3 inflammasome activation is involved in several other inflammatory diseases. Thus, we investigated the role of the NLRP3 inflammasome signaling pathway in the pathogenesis of DR. METHODS: Diabetes was induced in rats by streptozotocin treatment for 8 weeks. They were treated with NLRP3 shRNA or minocycline during the last 4 weeks. High glucose-exposed human retinal microvascular endothelial cells (HRMECs) were co-incubated with antioxidants or subjected to TXNIP or NLRP3 shRNA interference. RESULTS: In high glucose-exposed HRMECs and retinas of diabetic rats, mRNA and protein expression of NLRP3, ASC, and proinflammatory cytokines were induced significantly by hyperglycemia. Upregulated interleukin (IL)-1ß maturation, IL-18 secretion, and caspase-1 cleavage were also observed with increased cell apoptosis and retinal vascular permeability, compared with the control group. NLRP3 silencing blocked these effects in the rat model and HRMECs, confirming that inflammasome activation contributed to inflammation in DR. TXNIP expression was increased by reactive oxygen species (ROS) overproduction in animal and cell models, whereas antioxidant addition or TXNIP silencing blocked IL-1ß and IL-18 secretion in high glucose-exposed HRMECs, indicating that the ROS-TXNIP pathway mediates NLRP3 inflammasome activation. Minocycline significantly downregulated ROS generation and reduced TXNIP expression, subsequently inhibited NLRP3 activation, and further decreased inflammatory factors, which were associated with a decrease in retinal vascular permeability and cell apoptosis. CONCLUSIONS: Together, our data suggest that the TXNIP/NLRP3 pathway is a potential therapeutic target for the treatment of DR, and the use of minocycline specifically for such therapy may be a new avenue of investigation in inflammatory disease.

On-Line Screening, Isolation and Identification of Antioxidant Compounds of Helianthemum ruficomum.

Many Helianthemum species (Cistaceae) are recognized for their various medicinal virtues. Helianthemum ruficomum is an endemic species to the septentrional Sahara on which no report is available so far. The purpose of this work was to investigate the chemical composition and the radical scavenging capacity of this species and its isolated components. Collected from Mougheul (south-west of Algeria), the aerial parts were macerated with 80% EtOH/H2O, after evaporation, the remaining extract was diluted with H2O and extracted with petroleum ether, chloroform, ethyl acetate and n-butanol. EtOAc and n-BuOH extracts were evaluated for their free radical scavenging capacity by on-line HPLC-ABTS•+ assay. The obtained data which were confirmed by TEAC and ORAC assays, allowed guiding the fractionation of these extracts by CC, TLC and reverse phase HPLC. Among the components, 14 were isolated and identified by spectroscopic analyses: protocatechuic acid (1), trans-tiliroside (2), cis-tiliroside (3), astragalin (4), picein (7), vanillic acid 4-O-ß-d-glucopyranoside (8), lavandoside (9), 4-hydroxybenzoic acid 4-O-ß-d-glucopyranoside (10), nicotiflorin (11), rutin (12), vicenin-2 (13), narcissin (14) and stigmasterol (5) and ß-sitosterol (6) as a mixture (71% and 29%, respectively). Compounds 5, 7, 8, 9, 10 and 14 were new for the genus Helianthemum. The antioxidant power of all the isolated compounds was also evaluated by HPLC-ABTS•+, TEAC and ORAC assays. The results clearly indicated high antioxidant potential of the extracts and tested compounds of this species especially, compounds 1, 4, 8, 9, 10 and 12.

ANGPTL-4 correlates with vascular endothelial growth factor in patients with proliferative diabetic retinopathy.

PURPOSE: To investigate the relationship between angiopoietin-like protein 4 (ANGPTL-4) and vascular endothelial growth factor (VEGF) in the serum and vitreous of eyes in patients with proliferative diabetic retinopathy (PDR). METHODS: Thirty-five eyes of 35 patients with PDR, 20 eyes of 20 patients with non-proliferative diabetic retinopathy, 20 eyes of 20 patients with diabetes but no diabetic retinopathy, and 14 eyes of 14 nondiabetic patients with an idiopathic macular hole (IMH) were recruited from Shanghai First People's Hospital. The ANGPTL-4 and VEGF concentrations were determined using enzyme-linked immunosorbent assays. Group means were compared using one-way analysis of variance with GraphPad Prism 4.0 and SPSS ver. 17.0. The research followed the tenets of the Declaration of Helsinki. RESULTS: The ANGPTL-4 and VEGF levels were significantly higher in the vitreous and serum of patients with PDR compared with patients with IMH. There were significant correlations between the ANGPTL-4 and VEGF levels in the vitreous and serum of patients with PDR. The vitreous and serum ANGPTL-4 levels were also significantly correlated in patients with PDR. The ANGPTL-4 in both the vitreous and serum correlated with the serum triglyceride and high-density lipoprotein cholesterol levels. CONCLUSIONS: The ANGPTL-4 levels were markedly elevated and the ANGPTL-4 expression was directly correlated with the VEGF expression in the vitreous and serum of patients with PDR. The vitreous and serum ANGPTL-4 levels were also significantly correlated with serum lipids in patients with PDR. Our results suggest that the ANGPTL-4 may be used as a new therapeutic target for the treatment of PDR.

Synthesis and antitumor activity evaluation of novel ursolic acid derivatives.

Eleven novel ursolic acid (UA) derivatives were designed and synthesized with modification at positions of C-2, C-3, and C-28 of UA. Their structures were confirmed by MS, (1)H NMR, and elemental analysis. Their in vitro cytotoxicities against various cancer cell lines (HeLa, HepG2, and BGC-823) were evaluated by MTT assay. The results indicated that all compounds could inhibit cell proliferation of HeLa, HepG2, and BGC-823 cells. Among them, compounds I3 and I4 showed more potent cytotoxicity on these three tumor cells than gefitinib (positive control), worthy to be studied further.