Evolution of molecular switches for regulation of transgene expression by clinically licensed gluconate.

Synthetic biology holds great promise to improve the safety and efficacy of future gene and engineered cell therapies by providing new means of endogenous or exogenous control of the embedded therapeutic programs. Here, we focused on gluconate as a clinically licensed small-molecule inducer and engineered gluconate-sensitive molecular switches to regulate transgene expression in human cell cultures and in mice. Several switch designs were assembled based on the gluconate-responsive transcriptional repressor GntR from Escherichia coli. Initially we assembled OFF- and ON-type switches by rewiring the native gluconate-dependent binding of GntR to target DNA sequences in mammalian cells. Then, we utilized the ability of GntR to dimerize in the presence of gluconate to activate gene expression from a split transcriptional activator. By means of random mutagenesis of GntR combined with phenotypic screening, we identified variants that significantly enhanced the functionality of the genetic devices, enabling the construction of robust two-input logic gates. We also demonstrated the potential utility of the synthetic switch in two in vivo settings, one employing implantation of alginate-encapsulated engineered cells and the other involving modification of host cells by DNA delivery. Then, as proof-of-concept, the gluconate-actuated genetic switch was connected to insulin secretion, and the components encoding gluconate-induced insulin production were introduced into type-1 diabetic mice as naked DNA via hydrodynamic tail vein injection. Normoglycemia was restored, thereby showcasing the suitability of oral gluconate to regulate in situ production of a therapeutic protein.

A novel water-soluble Cu(II) gluconate complex inhibits cancer cell growth by triggering apoptosis and ferroptosis related mechanisms.

Metal copper complexes have attracted extensive attention as potential alternatives to platinum-based anticancer drugs due to their possible different modes of action. Herein, a new copper(II) gluconate complex, namely [Cu(DPQ)(Gluc)]·2H2O (CuGluc, DPQ = pyrazino[2,3-f][1,10]phenanthroline), with good water-solubility and high anticancer activity was synthesized by using D-gluconic acid (Gluc-2H) as an auxiliary ligand. The complex was well characterized by single-crystal X-ray diffraction analysis, elemental analysis, molar conductivity, and Fourier transform infrared spectroscopy (FTIR). The DNA-binding experiments revealed that CuGluc was bound to DNA by intercalation with end-stacking binding. CuGluc could oxidatively cleave DNA, in which 1O2 and H2O2 were involved. In addition, CuGluc was bound to the IIA subdomain of human serum albumin (HSA) through hydrophobic interaction and hydrogen bonding, showing a good affinity for HSA. The complex showed superior anticancer activity toward several cancer cells than cisplatin in vitro. Further studies indicated that CuGluc caused apoptotic cell death in human liver cancer (HepG2) cells through elevated intracellular reactive oxygen species (ROS) levels, mitochondrial dysfunction, cell cycle arrest, and caspase activation. Interestingly, CuGluc also triggered the ferroptosis mechanism through lipid peroxide accumulation and inhibition of glutathione peroxidase 4 (GPX4) activity. More importantly, CuGluc significantly inhibited tumor growth in vivo, which may benefit from the combined effects of apoptosis and ferroptosis. This work provides a promising strategy to develop highly effective antitumor copper complexes by coordinating with the glucose metabolite D-gluconic acid and exploiting the synergistic effects of apoptosis and ferroptosis mechanisms.

Evaluation of Effect of Natural Extract Sodium Gluconate on Smear Layer and Dentine Decalcification Compared with EDTA - An In-vitro Study.

OBJECTIVE: Mechanical instrumentation of the root canal system generates a smear layer on the canal walls which are removed most commonly with the help of chelators such as ethylenediaminetetraacetic acid (EDTA) but can potentially cause severe dentinal erosion. Considerable research has been conducted to find an al- ternative to EDTA which removes the smear layer without causing dentinal erosion. The current study aimed at evaluating the ability of sodium gluconate compared with that of 17% EDTA in smear layer removal along with its effect on dentine decalcification when used as a final irrigant. METHODS: Twenty single-rooted mandibular premolars were collected and prepared based on the pre-set criteria. Following preparation, the specimens were exposed to the test solutions as a final irrigant. Then the specimens were subjected to (Scanning electron microscope) SEM analysis at 1000x for evaluating the smear layer and 5000x for evaluating the dentinal erosion, and a Vickers microhardness tester was used for evaluat- ing the reduction in dentine microhardness post-treatment. The values obtained were analysed using SPSS software for a statistically significant difference with Mann-Whitney U test for evaluating of smear layer remov- al and dentinal erosion and using one-way (Analysis of variance) ANOVA test for microhardness evaluation. RESULTS: The smear layer removal capability of sodium gluconate was as effective as EDTA on the contrary so- dium gluconate did not cause any dentinal erosion compared to EDTA with a statistically significant difference (p=0.002 in middle third and p=0.001 in apical third of the canal). Microhardness reduction caused by sodium gluconate was less compared to EDTA, however, no statistically significant difference (p=0.113) was noted. CONCLUSION: Sodium gluconate, therefore, can produce a balance between smear layer removal and dentinal decalcification and can be considered a potential alternative to EDTA. (EEJ-2023-01-017).

Deep Learning-Based Image Analysis for the Quantification of Tumor-Induced Angiogenesis in the 3D In Vivo Tumor Model-Establishment and Addition to Laser Speckle Contrast Imaging (LSCI).

(1) Background: angiogenesis plays an important role in the growth and metastasis of tumors. We established the CAM assay application, an image analysis software of the IKOSA platform by KML Vision, for the quantification of blood vessels with the in ovo chorioallantoic membrane (CAM) model. We added this proprietary deep learning algorithm to the already established laser speckle contrast imaging (LSCI). (2) Methods: angiosarcoma cell line tumors were grafted onto the CAM. Angiogenesis was measured at the beginning and at the end of tumor growth with both measurement methods. The CAM assay application was trained to enable the recognition of in ovo CAM vessels. Histological stains of the tissue were performed and gluconate, an anti-angiogenic substance, was applied to the tumors. (3) Results: the angiosarcoma cells formed tumors on the CAM that appeared to stay vital and proliferated. An increase in perfusion was observed using both methods. The CAM assay application was successfully established in the in ovo CAM model and anti-angiogenic effects of gluconate were observed. (4) Conclusions: the CAM assay application appears to be a useful method for the quantification of angiogenesis in the CAM model and gluconate could be a potential treatment of angiosarcomas. Both aspects should be evaluated in further research.

Gluconate-Lactobionate-Dextran Perfusion Solutions Attenuate Ischemic Injury and Improve Function in a Murine Cardiac Transplant Model.

Static cold storage is the cheapest and easiest method and current gold standard to store and preserve donor organs. This study aimed to compare the preservative capacity of gluconate-lactobionate-dextran (Unisol) solutions to histidine-tryptophan-ketoglutarate (HTK) solution. Murine syngeneic heterotopic heart transplantations (Balb/c-Balb/c) were carried out after 18 h of static cold storage. Cardiac grafts were either flushed and stored with Unisol-based solutions with high-(UHK) and low-potassium (ULK) ± glutathione, or HTK. Cardiac grafts were assessed for rebeating and functionality, histomorphologic alterations, and cytokine expression. Unisol-based solutions demonstrated a faster rebeating time (UHK 56 s, UHK + Glut 44 s, ULK 45 s, ULK + Glut 47 s) compared to HTK (119.5 s) along with a better contractility early after reperfusion and at the endpoint on POD 3. Ischemic injury led to a significantly increased leukocyte recruitment, with similar degrees of tissue damage and inflammatory infiltrate in all groups, yet the number of apoptotic cells tended to be lower in ULK compared to HTK. In UHK- and ULK-treated animals, a trend toward decreased expression of proinflammatory markers was seen when compared to HTK. Unisol-based solutions showed an improved preservative capacity compared with the gold standard HTK early after cardiac transplantation. Supplemented glutathione did not further improve tissue-protective properties.

Effect of Dairy Matrix on the Postprandial Blood Metabolome.

This study investigated the postprandial plasma metabolome following consumption of four dairy matrices different in texture and structure: cheddar cheese (Cheese), homogenized cheddar cheese (Hom. Cheese), and micellar casein isolate (MCI) with cream (MCI Drink) or a MCI Gel. An acute, randomized, crossover trial in male participants (n = 25) with four test days was conducted. Blood samples were collected during an 8-h postprandial period after consumption of a meal similar in micro- and macronutrients containing one of the four dairy matrices, and the metabolome was analyzed using nuclear magnetic resonance (NMR) spectroscopy. A liquid dairy matrix (MCI Drink) resulted in a faster absorption of amino acids compared to products, representing either a semi-solid (MCI Gel and Hom. Cheese) or solid (Cheese) dairy matrix. For the MCI Gel, plasma concentration of acetic acid and formic acid increased approximately 2 h following consumption, while 3-hydroxybyturate and acetoacetic acid increased approximately 6 h after consumption. The structure and texture of the dairy matrix affected the postprandial absorption of amino acids, as revealed by the plasma metabolome. Our study furthermore pointed at endogenous effects associated with consumption of dairy products containing glucono-δ-lactone.

Evaluation of in vitro activity of copper gluconate against SARS-CoV-2 using confocal microscopy-based high content screening.

CONTEXT: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) that emerged late in 2019 is the etiologic agent of coronavirus disease 2019 (Covid-19). There is an urgent need to develop curative and preventive therapeutics to limit the current pandemic and to prevent the re-emergence of Covid-19. This study aimed to assess the in vitro activity of copper gluconate against SARS-CoV-2. METHODS: Vero E6 cells were cultured with or without copper gluconate 18-24 hours before infection. Cells were infected with a recombinant GFP expressing SARS-CoV-2. Cells were infected with a recombinant GFP expressing SARS-CoV-2. Infected cells were incubated in fresh medium containing varying concentration of copper gluconate (supplemented with bovine serum albumin or not) for an additional 48 -h period. The infection level was measured by the confocal microscopy-based high content screening method. The cell viability in presence of copper gluconate was assessed by XTT and propidium iodide assays. RESULTS: The viability of Vero E6 cells exposed to copper gluconate up to 200 µM was found to be similar to that of unexposed cells, but it dropped below 70 % with 400 µM of this agent after 72 h of continuous exposure. The infection rate was 23.8 %, 18.9 %, 20.6 %, 6.9 %, 5.3 % and 5.2 % in cells treated prior infection with 0, 2, 10, 25, 50 and 100 µM of copper gluconate respectively. As compared to untreated cells, the number of infected cells was reduced by 71 %, 77 %, and 78 % with 25, 50, and 100 µM of copper gluconate respectively (p < 0.05). In cells treated only post-infection, the rate of infection dropped by 73 % with 100 µM of copper gluconate (p < 0.05). However, the antiviral activity of copper gluconate was abolished by the addition of bovine serum albumin. CONCLUSION: Copper gluconate was found to mitigate SARS-CoV-2 infection in Vero E6 cells but this effect was abolished by albumin, which suggests that copper will not retain its activity in serum. Furthers studies are needed to investigate whether copper gluconate could be of benefit in mucosal administration such as mouthwash, nasal spray or aerosols.

Characterization of the Domoic Acid Uptake Mechanism of the Mussel (Mytilus galloprovincialis) Digestive Gland.

Cultures of the mussel Mytilus galloprovincialis are frequently affected by accumulation of the amnesic shellfish poisoning toxin domoic acid (DA). This species is characterized by a fast uptake and release of the toxin. In this work, the main characteristics of the uptake mechanism have been studied by incubation of digestive gland thin slices in media with different composition and DA concentration. DA uptake seems to follow Michaelis-Menten kinetics, with a very high estimated KM (1722 µg DA mL-1) and a Vmax of 71.9 µg DA g-1 h-1, which is similar to those found for other amino acids in invertebrates. Replacement of NaCl from the incubation media by Cl-choline (Na+-free medium) did not significantly reduce the uptake, but replacement by sorbitol (Na+-free and Cl--depleted medium) did. A new experiment replacing all chlorides with their equivalent gluconates (Na+- and Cl--free medium) showed an important reduction in the uptake that should be attributed to the absence of chloride, pointing to a Na+-independent, Cl- (or anion-) dependent transporter. In media with Na+ and Cl-, neither decreasing the pH nor adding cyanide (a metabolic inhibitor) had significant effect on DA uptake, suggesting that the transport mechanism is not H+- or ATP-dependent. In a chloride depleted medium, lowering pH or adding CN increased the uptake, suggesting that other anions could, at least partially, substitute chloride.

Strontium gluconate potently promotes osteoblast development and restores bone formation in glucocorticoid-induced osteoporosis rats.

Glucocorticoid-induced osteoporosis (GIOP) has emerged as a challenge after long-term glucocorticoid administration during the clinical therapy of diverse diseases. Although some candidates for GIOP treatment have been explored, there is still a lack of reliable drugs for GIOP prevention. In this study, rat bone marrow stem cells (rBMSCs) were utilized to investigate the feasibility of applying strontium gluconate (GluSr), which displays mild activity, easy absorption and good biocompatibility, for GIOP prevention. Thirty-two SD rats were divided into 4 groups to explore the effects of GluSr on osteoporosis rescue in vivo. Our results suggested that GluSr markedly alleviated dexamethasone (DEX)-induced apoptosis of osteoblast precursor cells and rBMSCs and enhanced rBMSC osteogenesis differentiation in vitro. GluSr also effectively promoted osteoblast survival, inhibited osteoclast differentiation and restored bone formation in GIOP rat models. Microarray analysis of the femora from GIOP rats treated with GluSr revealed that the signalling pathways of the glucocorticoid receptor (GR), oestrogen receptor gene (ESR) and vitamin D receptor (VDR) were involved in bone restoration by GluSr. In summary, our study proved that GluSr enhanced osteoblast differentiation and suppressed osteoclast activity both in vitro and in vivo. GluSr might function as a novel strontium reagent for GIOP prevention.

Corneometric evaluation of skin moisture after application of 10% and 30% gluconolactone.

BACKGROUND: Dry skin, caused by improper care or genetic conditions, can affect people of all ages. Skin hydration is determined its lipid content, which inhibits water loss from the epidermis, as well as other substances such as polyhydroxy acids and gluconolactone that can bind water. The aim of this study was to evaluate skin hydration after the application of 10% and 30% gluconolactone solution in a split face model. MATERIALS AND METHODS: Sixteen healthy women were qualified for the study. Three split face treatments were performed, with 10% and 30% gluconolactone solution applied to two sides of the face. Skin moisture was measured before each treatment and a week after the last treatment at three measurement sites on either side of the face, that is, on the forehead, around the eye and on the cheek. RESULTS: Corneometric measurements showed a significant increase in facial skin hydration after gluconolactone treatment. No significant differences were observed between the application of 10% and 30% solution. CONCLUSION: Gluconolactone is a moisturizing substance which works well in dry skin care.

Synthesis, DNA binding, antibacterial and anticancer properties of two novel water-soluble copper(II) complexes containing gluconate.

In this paper, two new Cu(II) complexes, [Cu(Gluc)(HPB)(H2O)]Gluc (CuG1) and [Cu(Gluc)(HPBC)(H2O)]Gluc (CuG2) (where HPB = 2-(2'-pyridyl)benzimidazole, HPBC = 5-chloro-2-(2'-pyridyl)benzimidazole, Gluc = d-Gluconic acid), with good water solubility were synthesized and characterized. These complexes exhibited a five-coordinated tetragonal pyramidal geometry. The DNA binding and cleavage properties of the complexes were investigated using multi-spectroscopy, viscosity measurement, molecular docking and gel electrophoresis analysis methods. The results showed that the complexes could interact with DNA by insertion and groove binding, and cleave CT-DNA through a singlet oxygen-dependent pathway in the presence of ascorbic acid. The studies on antibacterial and anticancer activities in vitro demonstrated that both complexes had good inhibitory activity against three Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes) and one Gram-negative bacterium (Escherichia coli) and good cytotoxic activity toward the tested cancer cells (A549, HeLa and SGC-7901). CuG2 showed higher antimicrobial and cytotoxic activities than CuG1, which was consistent with their binding strength and cleavage ability to DNA, indicating that their antimicrobial and cytotoxic activities may be related to the DNA interaction. Moreover, the cell-based mechanism studies have indicated that CuG1 and CuG2 could arrest the cell cycle at G2/M phase, elevate the levels of intracellular reactive oxygen species (ROS) and decrease the mitochondrial membrane potential (MMP). The results showed that the complexes could induce apoptosis through DNA-damaged and ROS-mediated mitochondrial dysfunction pathways. Finally, the in vivo antitumor study revealed that CuG2 inhibited tumor growth by 50.44%, which is better than that of cisplatin (40.94%).

Gluconate enhanced the water uptake and improved the growth of rice seedlings under PEG-induced osmotic stress.

Low-molecular-weight organic acid not only serves as a nutrient of plants or as a source of energy metabolism but also a bioactive molecule, which can be linked with hormones, nitrogen (N), and other signals to participate in regulating gene expression, stress response, growth, and development of plants via mechanisms that remain poorly understood. We investigated how the supply of gluconate and sulfate affects rice plant growth and water absorption at the same N supply under osmotic stress. Using a greenhouse hydroponic experimental approach, we assessed the physiology of rice seedlings supplied with C6H11O7NH4 (AG) and (NH4)2SO4 (AS) over multiple weeks. The root xylem sap rate in rice roots treated with AG increased significantly compared with AS treatment and the control under osmotic stress. The length of roots between 0.5 and 1.5 mm in diameter was obtained after treatment with polyethylene glycol (PEG) solutions containing AG, which was lower than those treated with PEG alone and PEG solutions containing AS. Compared with PEG alone and PEG solutions containing AS, AG induced a significant increase in root lignin under PEG-induced osmotic stress. However, relative to AS supply characteristics, the markedly reduced aerenchyma and porosity of roots, as well as higher root activity, increased fine root tips and length, and higher aquaporins and glutamate synthase (GS) activity in AG supply resulted in increased water uptake under osmotic stress. In addition, AG supply markedly increased leaf area and chlorophyll content. These results suggested that gluconate can enhance the water absorption capacity of the root system by promoting the growth and development of the root system, increasing the activity of aquaporin and GS and reducing the aeration tissue and porosity of the root system under osmotic stress.

Intestinal microbiota regulates anti-tumor effect of disulfiram combined with Cu2+ in a mice model.

BACKGROUND: A growing number of studies show that intestinal microbiota affect the therapeutic effects of antineoplastic agents. Disulfiram (tetraethylthiuram disulfide, DSF) is an old alcohol-aversion drug that has been shown to be effective against various types of cancers in preclinical studies, while few studies are carried out to explore its mechanism. METHODS: A mice model of melanoma xenograft was generated and treated with antibiotics (Abx), disulfiram/copper (DSF/Cu2+ ), Abx + DSF/Cu2+ , and the tumor volume and survival curve were observed. Hematoxylin-eosin (HE) staining and western blotting (WB) were used to observe the protein changes related to cell morphology, inflammation, and apoptosis in tumor tissues. Quantitative real time polymerase chain reaction (qPCR) was used to detect the expression of pro-inflammatory cytokines in tumors. High-throughput sequencing was used to detect the effects of Abx and DSF/Cu2+ on intestinal microbiota. RESULTS: The DSF/Cu2+ and Abx + DSF/Cu2+ markedly delayed tumor progression and prolonged mice survival, of which the combination of Abx and DSF/Cu2+ possessed the best anti-tumor effect. Abx + DSF/Cu2+ significantly reduced the pro-inflammatory cytokines Interleukin-1ß (IL-1ß), IL-6 and tumor necrosis factor α (TNF-α) in tumors, and significantly reduced the expression of phosphorylated-protein kinase B (p-AKT)/protein kinase B (AKT), toll-like receptors 4 (TLR-4), and phosphorylated- nuclear factor kappa-B (p-NFκB)/NFκB in tumors. Moreover our high-throughput sequencing first indicated that the sound anti-cancer effect of Abx + DSF/Cu2+ had a strong connection with the increased abundance of intestinal beneficial bacteria Akkermansia, as well as the reduced abundance of opportunistic pathogenic bacteria Campylobacterales, Helicobacteraceae, and Coriobacteriaceae. CONCLUSIONS: The disturbed intestinal microbiota (increased abundance of opportunistic pathogens Campylobacterales, Helicobacteraceae, and Coriobacteriaceae) and the over-activated TLR4/NF-κB signaling pathway in tumor tissues deteriorated the cancer development, and the using of antibiotics is benefit to enhance the therapeutic effect of DSF on tumors via inhibiting the growth of opportunistic pathogenic bacteria.

Kaempferol and zinc gluconate mitigate neurobehavioral deficits and oxidative stress induced by noise exposure in Wistar rats.

This study investigated the effects of kaempferol and zinc gluconate on neurobehavioural and oxidative stress changes in Wistar rats exposed to noise. Thirty (30) rats were randomly divided into five groups: Groups I and II were administered with deionized water (DW); Group III, kaempferol (K); Group IV, zinc gluconate (Zn); Group V, kaempferol + zinc gluconate. Groups II, III, IV, and V were subjected to noise stress (N) induced by exposing rats to 100 dB (4 h/day) for 15 days, from day 33 to day 48 after starting the drug treatments. Neuromuscular coordination, motor coordination, motor strength, sensorimotor reflex, and learning and memory, were evaluated using standard laboratory methods. Levels of nitric oxide (NO), malondialdehyde (MDA) and activities of glutathione peroxidase (GPx), catalase and superoxide dismutase (SOD) were evaluated in the hippocampus. Exposure of rats to noise, induced significant neurobehavioural deficits and oxidative stress while the combined administration of kaempferol and zinc gluconate significantly (P < 0.05) improved open-field performance, motor coordination, motor strength, sensorimotor reflex, and learning and memory. Co-administration of kaempferol and zinc gluconate ameliorated noise-induced oxidative stress as demonstrated by the significantly increased activities of GPx, catalase, and SOD, and decreased levels of NO and MDA (P < 0.05 and P < 0.01 respectively), compared to the DW + N group. Our results suggest that oxidative stress, evidenced by increased NO and MDA concentration and decreased activities of GPx, catalase and SOD, were involved in the molecular mechanism underlying neurobehavioural impairment in Wistar rats, exposed to noise stress. Single treatment of kaempferol exerted a more potent mitigative effect than zinc gluconate, while their combination produced an improved outcome.

Study Protocol for Better Evidence for Selecting Transplant Fluids (BEST-Fluids): a pragmatic, registry-based, multi-center, double-blind, randomized controlled trial evaluating the effect of intravenous fluid therapy with Plasma-Lyte 148 versus 0.9% saline on delayed graft function in deceased donor kidney transplantation.

BACKGROUND: Delayed graft function, the requirement for dialysis due to poor kidney function post-transplant, is a frequent complication of deceased donor kidney transplantation and is associated with inferior outcomes and higher costs. Intravenous fluids given during and after transplantation may affect the risk of poor kidney function after transplant. The most commonly used fluid, isotonic sodium chloride (0.9% saline), contains a high chloride concentration, which may be associated with acute kidney injury, and could increase the risk of delayed graft function. Whether using a balanced, low-chloride fluid instead of 0.9% saline is safe and improves kidney function after deceased donor kidney transplantation is unknown. METHODS: BEST-Fluids is an investigator-initiated, pragmatic, registry-based, multi-center, double-blind, randomized controlled trial. The primary objective is to compare the effect of intravenous Plasma-Lyte 148 (Plasmalyte), a balanced, low-chloride solution, with the effect of 0.9% saline on the incidence of delayed graft function in deceased donor kidney transplant recipients. From January 2018 onwards, 800 participants admitted for deceased donor kidney transplantation will be recruited over 3 years in Australia and New Zealand. Participants are randomized 1:1 to either intravenous Plasmalyte or 0.9% saline peri-operatively and until 48 h post-transplant, or until fluid is no longer required; whichever comes first. Follow up is for 1 year. The primary outcome is the incidence of delayed graft function, defined as dialysis in the first 7 days post-transplant. Secondary outcomes include early kidney transplant function (composite of dialysis duration and rate of improvement in graft function when dialysis is not required), hyperkalemia, mortality, graft survival, graft function, quality of life, healthcare resource use, and cost-effectiveness. Participants are enrolled, randomized, and followed up using the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry. DISCUSSION: If using Plasmalyte instead of 0.9% saline is effective at reducing delayed graft function and improves other clinical outcomes in deceased donor kidney transplantation, this simple, inexpensive change to using a balanced low-chloride intravenous fluid at the time of transplantation could be easily implemented in the vast majority of transplant settings worldwide. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12617000358347. Registered on 8 March 2017. ClinicalTrials.gov: NCT03829488. Registered on 4 February 2019.

Development of sodium chlorite and glucono delta-lactone incorporated PLA film for microbial inactivation on fresh tomato.

Chlorine dioxide (ClO2) is an effective disinfectant used in the sanitization of fresh produce. Glucono delta-lactone (GDL), widely used as an acidifier during food processing, can be partially hydrolyzed to become a weak acid-gluconic acid under chemical equilibrium upon dissolution in water. This study focused on the development of a novel polylactic acid (PLA) film which incorporated with sodium chlorite (NaClO2) and GDL for ClO2(g) generation. The effects of PLA amount, NaClO2 + GDL/PLA ratio, NaClO2/GDL ratio, temperature and relative humidity on the release profiles of ClO2(g) were elucidated. The storage test indicated that film efficacy was well maintained after 4 weeks of storage under ambient conditions. The microbial inactivation results revealed that ClO2(g) generated from the films reduced populations of surface-inoculated Salmonella and Escherichia coli O157:H7 from ca. 5 log CFU/tomato to undetectable level (<1 log CFU/tomato) within 2 and 4 h respectively and the complete elimination in populations of both bacterial species was maintained throughout the 14-day storage period at both 10 and 22 °C. The sensory properties of treated tomatoes were evaluated and exhibited no significant difference (p > 0.05) compared to controls except for appearance on day 14 under 22 °C storage.

Gelation of milks of different species (dairy cattle, goat, sheep, red deer, and water buffalo) using glucono-δ-lactone and pepsin.

Dynamic low-amplitude oscillatory rheology was used to study the gelation properties of skim milk gels made at 37°C, using glucono-δ-lactone alone (acid gels) or a combination of glucono-δ-lactone and porcine pepsin ("combination gels"). The protein contents of the skim milks increased in the order goat milk < cattle milk < buffalo milk < sheep milk < deer milk, whereas the average casein micelle diameters increased in the order cattle milk < buffalo milk < goat milk < sheep milk ≃ deer milk. The gelation pH (4.55-4.73) of all milks were close to the isoelectric pH (4.6) of casein, except for buffalo milk, which had a significantly higher gelation pH (5.72). The storage moduli (G') of the acid gels increased with time in the milks of all species except for buffalo milk, for which a double peak in G' was observed. The final storage moduli after 6 h (G'final) increased in the order goat milk < cattle milk < sheep milk < deer milk < buffalo milk. In general, for the combination gels, the G'final values and the gelation pH increased to variable extents, except for goat milk. Confocal scanning laser microscopy showed that goat milk and cattle milk formed gels with more open protein networks compared with the dense clustered protein networks of the milks with high protein content (buffalo, sheep, and deer milks). This study indicates that milks from different species respond differently under the action of an acid precursor and pepsin. These results can be used to provide a better understanding of curd making and the digestion properties of noncattle milks.

Oral Administration of Strontium Gluconate Effectively Reduces Articular Cartilage Degeneration Through Enhanced Anabolic Activity of Chondrocytes and Chondrogenetic Differentiation of Mesenchymal Stromal Cells.

Osteoarthritis (OA), a common degenerative disease affecting articular cartilage, is caused by multiple factors, and currently, there are few approaches to effectively delay its progression. This study aimed to evaluate whether a strontium compound (in the form of strontium gluconate, Glu-Sr) could reduce OA pathology severity in osteoarthritic rat models by directly targeting chondrocytes, including catabolic/anabolic activities and/or chondrogenic differentiation. Glu-Sr was administered to OA rats by oral gavage beginning during OA induction and continuing for 8 weeks. Glu-Sr treatment was found to significantly reduce cartilage degeneration and delay OA progression. Further examination showed that collagen II, Sox9, and aggrecan (ACAN) genes were up-regulated whereas IL-1ß was down-regulated in chondrocytes isolated from Glu-Sr-treated rats. Glu-Sr also antagonized the catabolic effects of IL-1ß on chondrocytes. Furthermore, Glu-Sr was shown to promote the chondrogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs), possibly through promoting chondrogenic gene expression, including CTGF and FGF1, as revealed by RNA-sequencing (RNA-seq). These results suggest that systemic administration of Glu-Sr may be useful in prophylactic and therapeutic treatment of chronic cartilage degradation through affecting multiple steps from chondrogenic differentiation of progenitors to matrix formation in mature chondrocytes.

Effects of zinc supplementation on serum adiponectin concentration and glycemic control in patients with type 2 diabetes.

BACKGROUND: Previous studies have suggested that zinc is involved in insulin homeostasis. Adiponectin is a well-known adipokine with anti-diabetic, anti-atherogenic, and anti-inflammatory properties. The aim of this study was to investigate the effect of zinc supplementation on glycemic control, and the potential mediating role of adiponectin, in patients with type 2 diabetes. METHODS: In this randomized double-blind placebo-controlled clinical trial, 60 patients with diabetes, 30-60 years, were randomized to receive either 30 mg/d zinc (as zinc gluconate) or placebo for 12 weeks. Circulating levels of adiponectin, zinc, glucose homeostasis parameters, and lipid profiles, as well as anthropometric parameters and dietary intakes, were assessed. RESULTS: About 53.3% of the patients had zinc insufficiency at baseline. Serum zinc levels improved significantly in the intervention than control group following 12 weeks supplementation (P < 0.001). Adiponectin (1.23 ± 2.23 µg/ml, P = 0.006) and insulin (3.6 ± 4.66 µIU/ml, P = 0.001) levels increased significantly compared to baseline in the zinc group; but this change was not significant compared with the control group. Following supplementation, there were no significant differences in glycemic control and anthropometric parameters between the two groups. Serum HDL levels increased significantly in the zinc (5.37 ± 14.8 mg/dl) compared to control (-1.53 ± 6.9 mg/dl) group following supplementation (P = 0.039). CONCLUSION: Despite a significant increase in serum zinc level, no improvement was observed in glycemic control, following 12 weeks supplementation with 30 mg/d zinc (as zinc gluconate). Zinc supplementation restored adiponectin concentrations partly within the intervention group, and increased HDL levels compared to the control group. The current findings did not support improvement in glucose homeostasis following zinc supplementation in patients with type 2 diabetes under the present study design.

Berberine induces ZIP14 expression and modulates zinc redistribution to protect intestinal mucosal barrier during polymicrobial sepsis.

AIMS: The present study investigated if berberine might induce Zrt-Irt-like protein 14 (ZIP14) and affect zinc redistribution to protect intestinal barrier in sepsis. MAIN METHODS: Rodent model of sepsis was induced by cecal ligation and puncture (CLP). Plasma endotoxin was assayed by LAL test and plasma zinc was measured by flame atomic spectrophotometer. Gut mucosal permeability was determined by plasma FITC-dextran. Zinc content and ZIP14 mRNA in gut mucosa were assayed by spectrophotometer and qRT-PCR, respectively. Tight junction integrity of Caco-2 was evaluated by transepithelial electrical resistance (TEER). Tight junction (TJ) protein expression was detected by Western blotting. KEY FINDINGS: Berberine and zinc gluconate pretreatment to CLP rats improved survival rate, reduced plasma endotoxin level, alleviated hypozincemia, increased zinc accumulation and ZIP14 mRNA expression in the intestinal mucosa. Berberine and zinc gluconate pretreatment decreased CLP-elicited intestinal hyperpermeability to FITC-dextran. These effects of berberine in vivo were abolished by AG1024. In vitro, lipopolysaccharide (LPS) repressed zinc transfer into Caco-2 cells exposed to zinc gluconate. Berberine and IGF-I treatment increased ZIP14 protein expression and promoted zinc transfer into Caco-2 cells exposed to zinc gluconate plus LPS. Berberine treatment induced TJ protein (claudin-1 and occludin) and raised TEER in LPS-treated Caco-2 cells. These effects of berberine in vitro were partially inhibited by ZIP14 siRNA. SIGNIFICANCE: The present study reveals that berberine induces ZIP14 expression and affects zinc re- distribution to protect intestinal barrier in sepsis, which is partially linked with the activation of IGF-I signaling.