Dapagliflozin prevents ERK activation and SGLT2-dependent endoglin upregulation in a mechanically provoked cardiac injury model.

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are rapidly gaining ground in the treatment of heart failure (HF) with reduced ejection fraction (HFrEF) and acute myocardial infarction (AMI) by an unknown mechanism. Upregulation of Na+/H+ exchanger 1 (NHE1), SGLT1, and Ca2+/calmodulin-dependent protein kinase II (CaMKII) in the diseased hearts was found to be attenuated by prolonged SGLT2i treatment. Unfortunately, dapagliflozin is not well understood as to how Na+/Ca2+ homeostasis is affected in cardiomyocytes. In this study, we aimed to investigate whether mechanical stretch in cardiomyocytes upregulate SGLT2, resulted to loss of Na+/Ca2+ homeostasis via ERK and eNOS signaling. AMI (+) and AMI (-) serum levels were estimated using ELISA assays of TGFß-1 or endoglin (CD105). Human cardiomyocyte cell line AC16 was subjected to different stresses: 5% mild and 25% aggressive, at 1 Hz for 24 h. Immunofluorescence assays were used to estimate troponin I, CD105, SGLT1/2, eNOSS633, and ERK1/2T202/Y204 levels was performed for 5% (mild), and 25% elongation for 24 h. AMI (+) serum showed increased TGFß1 and CD105 compared to AMI (-) patients. In consistent, troponin I, CD105, SGLT1/2, eNOSS633 and ERK1/2T202/Y204 were upregulated after 25% of 24 h cyclic stretch. Dapagliflozin addition caused SGLT2 inhibition, which significantly decreased troponin I, CD105, SGLT1/2, eNOSS633, and ERK1/2T202/Y204 under 25% cyclic stretching. In summary, SGLT2 may have sensed mechanical stretch in a way similar to cardiac overloading as in vivo. By blocking SGLT2 in stretched cardiomyocytes, the AMI biomarkers (CD105, troponin I and P-ERK) were decreased, potentially to rescue eNOS production to maintain normal cellular function. This discovery of CD105 and SGLT2 increase in mechanically stretched cardiomyocytes suggests that SGLT2 may conceive a novel role in direct or indirect sensing of mechanical stretch, prompting the possibility of an in vitro cardiac overloaded cell model, an alternative to animal heart model.

Microglial activation and toll-like receptor 4-Dependent regulation of angiotensin II type I receptor-mu-opioid receptor 1 heterodimerization and hypertension in fructose-fed rats.

Our previous study reported that the heterodimer of Angiotensin II Type I Receptor (AT1R) and Mu-Opioid Receptor 1 (MOR1) involves Nitric Oxide (NO) reduction which leads to elevation of blood pressure. Secondly, we showed that Toll-like Receptor 4 (TLR4) may be involved in the heterodimerization of AT1R and MOR1 in the brainstem Nucleus Tractus Solitarii (NTS), which regulates systemic blood pressure and gastric nitric oxide through the insulin pathway. Here, we investigated the role of microglial activation and TLR4 in the heterodimerization of AT1R and MOR1. Hypertensive rats were established after four weeks of fructose consumption. SBP of rats was measured using non-invasive blood pressure method. PLA technique was utilized to determine protein-protein interaction in the nucleus tractus solitarii. Results showed that the level of MOR-1 and AT1R was induced significantly in the fructose group compared with control. PLA signal potentially showed that AT1R and MOR1 were formed in the nucleus tractus solitarii after fructose consumption. Meanwhile, the innate immune cell in the CNS microglia was observed in the nucleus tractus solitarii using biomarkers and was activated. TLR4 inhibitor CLI-095, was administered to animals to suppress the neuroinflammation and microglial activation. CLI-095 treatment reduced the heterodimer formation of AT1R and MOR1 and restored nitric oxide production in the nucleus tractus solitarii. These findings imply that TLR4-primed neuroinflammation involves formation of heterodimers AT1R and MOR1 in the nucleus tractus solitarii which leads to increase in systemic blood pressure.

Recent Advances in Engineering Carriers for siRNA Delivery.

RNA interference (RNAi) technology has been a promising treatment strategy for combating intractable diseases. However, the applications of RNAi in clinical are hampered by extracellular and intracellular barriers. To overcome these barriers, various siRNA delivery systems have been developed in the past two decades. The first approved RNAi therapeutic, Patisiran (ONPATTRO) using lipids as the carrier, for the treatment of amyloidosis is one of the most important milestones. This has greatly encouraged researchers to work on creating new functional siRNA carriers. In this review, the recent advances in siRNA carriers consisting of lipids, polymers, and polymer-modified inorganic particles for cancer therapy are summarized. Representative examples are presented to show the structural design of the carriers in order to overcome the delivery hurdles associated with RNAi therapies. Finally, the existing challenges and future perspective for developing RNAi as a clinical modality will be discussed and proposed. It is believed that the addressed contributions in this review will promote the development of siRNA delivery systems for future clinical applications.

Pyrazine Functionalization in Eu-MOF for Exclusive Ratiometric Luminescence Sensing of PO43.

Single-emission luminescence sensors are less than satisfactory for complex systems due to their susceptibility to environmental disturbances. Lanthanum-based metal-organic frameworks (Ln-MOFs) with highly stable ratiometric dual-emission are regarded as promising luminescence probes owing to their fascinating ligand-to-metal energy transfer behaviors (also known as the antenna effect). Herein, we report the synthesis of a pair of isostructural europium-based MOFs (termed JNU-219 and JNU-220) by utilizing two X-shaped tetracarboxylate linkers, 4,4',4″,4‴-benzene-2,3,5,6-tetrayl-tetrabenzoate (BTEB) and 4,4',4″,4‴-pyrazine-2,3,5,6-tetrayl-tetrabenzoate (BTTB). Both JNU-219 and JNU-220 present the characteristic red luminescence of Eu3+, yet the pyrazine functionalization of the BTTB linker renders JNU-220 with significantly increased luminescence emission, almost 30 times that of JNU-219. As a result, the detection limit of JNU-220 for the ratiometric luminescence sensing of PO43- was determined to be as low as 0.22 µM, which is far superior to those of other reported MOF materials. Additionally, we demonstrate the excellent stability and reusability of JNU-220, further verifying its potential as a robust ratiometric luminescence probe.

Attenuation of epithelial-mesenchymal transition via SGLT2 inhibition and diabetic cataract suppression by dapagliflozin nanoparticles treatment.

AIMS: Chronic hyperglycemia triggers overproduction of AKR1B1 (aldo-keto reductase family 1 member B) and receptor for advanced glycation end product (RAGE), which causes epithelial-mesenchymal transition (EMT) in the lens epithelial cells (LECs) of diabetic mellitus (DM) cataracts. However, it is unclear whether EMT in LECs is related to abnormal increase of SGLT2. Sodium glucose cotransporter 2 (SGLT2) inhibitor, also known as dapagliflozin (Dapa) can be used to treat diabetes. Here, we examined how Dapa or nano eye-drops (DapaN) reduce EMT in LECs of DM cataracts. The nano eye-drop provides an ophthalmic treatment that suppressed diabetic cataract progression and improved potency with reduced side effects. MAIN METHODS: SD rats were injected with streptozocin (STZ) (65 mg/kg, ip), nano-Dapa drops (0.456 mg/10 ml/eye) or Dapa (1.2 mg/kg/day) treatment for 6-12 weeks. Immunofluorescence staining was used for protein quantification of RAGE, SGLT2, N-cadherin and E-cadherin in the LECs of rats. KEY FINDINGS: In this study, Dapa applies nanotechnology-based delivery system and it contains polyvinylpyrrolidone (PVP) and HPBCD. Dapa showed therapeutic effect on DM cataracts, wherein it targeted EMT biomarker, E-cadherin. The nano-Dapa drops or oral Dapa inhibited SGLT2, suppressed AKR1B1 expression, decreased AcSOD2- and RAGE-induced EMT in diabetic cataracts. Our findings suggest that nanotechnology-based Dapa eye drops (Dapa-PVP-HPBCD) can effectively improve solubility of Dapa in aqueous solution. SIGNIFICANCE: Taken together, results suggest that the SGLT2-mediated DM cataract therapy may involve the AKR1B1-RAGE-AcSOD2-EMT pathway. The nano eye drops and Dapa show potential beneficial effects for cataract prevention. This study conveys new insights into cataract treatment and supplementation of nano-Dapa drops shows promising result in preventing diabetic cataracts.

Linker Engineering for Reactive Oxygen Species Generation Efficiency in Ultra-Stable Nickel-Based Metal-Organic Frameworks.

Interfacial charge transfer on the surface of heterogeneous photocatalysts dictates the efficiency of reactive oxygen species (ROS) generation and therefore the efficiency of aerobic oxidation reactions. Reticular chemistry in metal-organic frameworks (MOFs) allows for the rational design of donor-acceptor pairs to optimize interfacial charge-transfer kinetics. Herein, we report a series of isostructural fcu-topology Ni8-MOFs (termed JNU-212, JNU-213, JNU-214, and JNU-215) with linearly bridged bipyrazoles as organic linkers. These crystalline Ni8-MOFs can maintain their structural integrity in 7 M NaOH at 100 °C for 24 h. Experimental studies reveal that linker engineering by tuning the electron-accepting capacity of the pyrazole-bridging units renders these Ni8-MOFs with significantly improved charge separation and transfer efficiency under visible-light irradiation. Among them, the one containing a benzoselenadiazole unit (JNU-214) exhibits the best photocatalytic performance in the aerobic oxidation of benzylamines with a conversion rate of 99% in 24 h. Recycling experiments were carried out to confirm the stability and reusability of JNU-214 as a robust heterogeneous catalyst. Significantly, the systematic modulation of the electron-accepting capacity of the bridging units in donor-acceptor-donor MOFs provides a new pathway to develop viable noble-metal-free heterogeneous photocatalysts for aerobic oxidation reactions.

Creation of Chitosan-Based Nanocapsule-in-Nanofiber Structures for Hydrophobic/Hydrophilic Drug Co-Delivery and Their Dressing Applications in Diabetic Wounds.

Nanofiber meshes (NFMs) loaded with therapeutic agents are very often employed to treat hard-to-heal wounds such as diabetic wounds. However, most of the NFMs have limited capability to load multiple or hydrophilicity distinctive-therapeutic agents. The therapy strategy is therefore significantly hampered. To tackle the innate drawback associated with the drug loading versatility, a chitosan-based nanocapsule-in-nanofiber (NC-in-NF) structural NFM system is developed for simultaneous loading of hydrophobic and hydrophilic drugs. Oleic acid-modified chitosan is first converted into NCs by the developed mini-emulsion interfacial cross-linking procedure, followed by loading a hydrophobic anti-inflammatory agent Curcumin (Cur) into the NCs. Sequentially, the Cur-loaded NCs are successfully introduced into reductant-responsive maleoyl functional chitosan/polyvinyl alcohol NFMs containing a hydrophilic antibiotic Tetracycline hydrochloride. Having a co-loading capability for hydrophilicity distinctive agents, biocompatibility, and a controlled release property, the resulting NFMs have demonstrated the efficacy on promoting wound healing either in normal or diabetic rats.

Efficiency comparison of an isoeugenol-derivated compound, eugenosedin-A, with glibenclamide and pioglitazone in protecting cardiovascular dysfunction of diabetic SHR.

This study was to investigate three agents possible protective effect against DM-induced cardiovascular dysfunction in spontaneously hypertensive rats (SHR). Control group was fed normal diet, DM group was injected with STZ/NA and fed high fat diet (HFD), and treatment groups were given STZ/NA, fed HFD, and then oral gavaged with eugenosedin-A (Eu-A), glibenclamide (Gli), or pioglitazone (Pio) 5 mg/kg/per day for 4-week, respectively. Eu-A, Gli, and Pio clearly ameliorated the changes of body weight, cardiac weight, and the biochemical parameters, cardiovascular disorders and inflammation. Like Gli and Pio, Eu-A may be effectively to control DM and the cardiovascular dysfunction.

Preparation of CO2 -Based Cationic Polycarbonate/Polyacrylonitrile Nanofibers with an Optimal Fibrous Microstructure for Antibacterial Applications.

Utilizing CO2 as one of the monomer resources, poly(vinylcyclohexene carbonates) (PVCHCs) are used as the precursor for preparing cationic PVCHCs (CPVCHCs) via thiol-ene click functionalization. Through the functionalization, CPVCHC-43 with a tertiary amine density of 43% relative to the backbone is able to display a significantly antibacterial ability against Staphylococcus aureus (S. aureus). Blending CPVCHC-43 with polyacrylonitrile (PAN), CPVCHC/PAN nanofiber meshes (NFMs) have been successfully prepared by electrospinning. More importantly, two crucial fibrous structural factors including CPVCHC/PAN weight ratio and fiber diameter have been systematically investigated for the effects on the antibacterial performance of the NFMs. Sequentially, a quaternization treatment has been employed on the NFMs with an optimal fibrous structure to enhance the antibacterial ability. The resulting quaternized NFMs have demonstrated the great biocidal effects against Gram-positive and Gram-negative bacteria. Moreover, the excellent biocompatibility of the quaternized NFMs have also been thoroughly evaluated and verified.

Blocking of SGLT2 to Eliminate NADPH-Induced Oxidative Stress in Lenses of Animals with Fructose-Induced Diabetes Mellitus.

Chronic hyperglycemia triggers an abnormal rise in reactive oxygen species (ROS) that leads to blindness in patients with diabetes mellitus (DM) and cataracts. In this study, the effects of dapagliflozin, metformin and resveratrol on ROS production were investigated in lens epithelial cells (LECs) of animals with fructose-induced DM. LECs were isolated from patients without DM, or with DM devoid of diabetic retinopathy. Animals were treated with 10% fructose for 8 weeks to induce DM, which was verified by monitoring blood pressure and serum parameters. For drug treatments, 1.2 mg/day of dapagliflozin was given for 2 weeks, 500 mg/kg/day of metformin was given, and 10 mg/kg/day of resveratrol was given. Dihydroethidium was used to stain endogenous O2˙- production in vivo of the LECs. Superoxide production was expressed in the cataract of DM, or patients without DM. Sodium-glucose cotransporter 2 (SGLT2), glucose transporter 1 (GLUT1), GLUT5, the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit p47/p67-phox, NOX4 and RAGE were significantly increased in LECs with DM. In addition, the dapagliflozin treatment reduced GLUT5, p47/p67-phox, NADPH oxidase 4 (NOX4) and receptor for advanced glycation end products (RAGE) expressions. On the contrary, metformin or resveratrol inhibited p47-phox, GLUT5, and SGLT2 expressions, but not nuclear factor erythroid 2-related factor 2 (NRF2). In summary, dapagliflozin, metformin or resveratrol down-regulated p47-phox expression through SGLT2 inactivation and ROS reduction. These important findings imply that SGLT2 can be blocked to ameliorate oxidative stress in the cataracts of DM patients.

Pre-germinated brown rice alleviates non-alcoholic fatty liver disease induced by high fructose and high fat intake in rat.

In past researches, we had been proved the action mechanism of pre-germinated brown rice (PGBR) to treat metabolic syndrome and diabetes mellitus. This study was to investigate the protective effect of PGBR in high fructose and high fat-induced non-alcoholic fatty liver disease (NAFLD) in rodents. WKY rats were divided into: Control group was fed normal drinking water and diet; FLD group was fed 10% high-fructose-water (HFW) and high-fat-diet (HFD); PGBR group was given HFW, and HFD mixed PGBR. After four weeks, the body, hepatic and cardiac weight gains of FLD group had significant increases than that of Control group. The enhanced blood pressure and heart rate, hypertriglyceridemia, hyperuricemia, and higher liver function index (GPT levels) were observed; meanwhile, the IL-6 and TNF-α levels of serum, and TG level of liver were also elevated in FLD group. The related protein expressions of lipid synthesis, inflammation, cardiac fibrosis, and hypertrophy were deteriorated by HFW/HFD. However, in treatment group, PGBR decreased all above influenced parameters, additionally GOT; and related protein expressions. PGBR treated HFW/HFD-induced NAFLD and cardiac complications might be via improving lipid homeostasis, and inhibiting inflammation. Together, PGBR could be used as a healthy food for controlling NAFLD and its' cardiac dysfunction.

Glut5 Knockdown in the Nucleus Tractus Solitarii Alleviates Fructose-Induced Hypertension in Rats.

BACKGROUND: Several studies have suggested mechanisms whereby excessive fructose intake increases blood pressure (BP). Glucose transporter 5 (GLUT5) is a fructose transporter expressed on enterocytes, and its involvement in the nucleus tractus solitarius (NTS)-modulated increase in BP following fructose intake remains unclear. OBJECTIVES: Herein, we investigated whether NTS Glut5 knockdown (KD) can alleviate fructose-induced hypertension in rat models. METHODS: Male Wistar-Kyoto rats (6-8 weeks old; average weight: 230 g) were randomly assigned into 4 groups [control (Con), fructose (Fru), fructose + scrambled (Fru + S), and Fru +  KD]. The Con group rats had ad libitum access to regular water, and the other 3 groups were provided 10% fructose water ad libitum for 4 weeks (2 weeks before lentiviral transfection in the Fru + S and Fru + KD groups). Glut5 short hairpin RNA was delivered into the NTS of rats using a lentivirus system. Fructose-induced hypertension was assessed via the tail-cuff technique, a noninvasive blood pressure measurement approach. GLUT5-associated and other insulin signaling pathways in the NTS of rats were assessed using immunofluorescence and immunoblotting analyses. We evaluated between-group differences using the Mann-Whitney U test or Kruskal-Wallis 1-way ANOVA. RESULTS: Compared with the Fru + S group, the Fru + KD group had reduced sympathetic nerve hyperactivity (48.8 ± 3.2 bursts/min; P < 0.05), improved central insulin signaling, upregulated protein kinase B (AKT; 3.0-fold) and neuronal NO synthase (nNOS; 2.78-fold) expression, and lowered BP (17 ± 1 mmHg, P < 0.05). Moreover, Glut5 KD restored signaling dependent on adenosine 5'-monophosphate-activated protein kinase and reduced fructose-induced oxidative stress 2.0-fold, and thus decreased NAD(P)H oxidase in p67-phox 1.9-fold within the NTS. CONCLUSIONS: Fructose-induced reactive oxygen species generates in the NTS of rats through GLUT5 and receptor for advanced glycation end products signaling, thus impairing the AKT-nNOS-NO signaling pathway and ultimately causing hypertension.

µ-Opioid Receptor-Mediated AT1R-TLR4 Crosstalk Promotes Microglial Activation to Modulate Blood Pressure Control in the Central Nervous System.

Opioids, a kind of peptide hormone involved in the development of hypertension, cause systemic and cerebral inflammation, and affects regions of the brain that are important for blood pressure (BP) control. A cause-and-effect relationship exists between hypertension and inflammation; however, the role of blood pressure in cerebral inflammation is not clear. Evidence showed that AT1R and µOR heterodimers' formation in the NTS might lead to the progression of hypertension. In this study, we investigated the formation of the µOR/AT1R heterodimer, determined its correlation with µORs level in the NTS, and explored the role of TLR4-dependent inflammation in the development of hypertension. Results showed that Ang II increased superoxide and Iba-1 (microgliosis marker: ionized calcium-binding adaptor molecule (1) levels in the NTS of spontaneously hypertensive rats (SHRs). The AT1R II inhibitor, losartan, significantly decreased BP and abolished superoxide, Iba-1, TLR4 expression induced by Ang II. Furthermore, losartan significantly increased nNsOSS1416 phosphorylation. Administration of a µOR agonist or antagonist in the NTS of WKY and SHRs increased endogenous µ-opioids, triggered the formation of µOR/AT1R heterodimers and the TLR4-dependent inflammatory pathway, and attenuated the effect of depressor nitric oxide (NO). These results imply an important link between neurotoxicity and superoxides wherein abnormal increases in NTS endogenous µ-opioids promote the interaction between Ang II and µOR, the binding of Ang II to AT1R, and the activation of microglia. In addition, the interaction between Ang II and µOR enhanced the formation of the AT1R and µOR heterodimers, and inactivated nNOS-derived NO, leading to the development of progressive hypertension.

Mechanical Stretching-Induced Traumatic Brain Injury Is Mediated by the Formation of GSK-3ß-Tau Complex to Impair Insulin Signaling Transduction.

Traumatic brain injury confers a significant and growing public health burden. It is a major environmental risk factor for dementia. Nonetheless, the mechanism by which primary mechanical injury leads to neurodegeneration and an increased risk of dementia-related diseases is unclear. Thus, we aimed to investigate the effect of stretching on SH-SY5Y neuroblastoma cells that proliferate in vitro. These cells retain the dopamine-ß-hydroxylase activity, thus being suitable for neuromechanistic studies. SH-SY5Y cells were cultured on stretchable membranes. The culture conditions contained two groups, namely non-stretched (control) and stretched. They were subjected to cyclic stretching (6 and 24 h) and 25% elongation at 1 Hz. Following stretching at 25% and 1 Hz for 6 h, the mechanical injury changed the mitochondrial membrane potential and triggered oxidative DNA damage at 24 h. Stretching decreased the level of brain-derived neurotrophic factors and increased amyloid-ß, thus indicating neuronal stress. Moreover, the mechanical injury downregulated the insulin pathway and upregulated glycogen synthase kinase 3ß (GSK-3ß)S9/p-Tau protein levels, which caused a neuronal injury. Following 6 and 24 h of stretching, GSK-3ßS9 was directly bound to p-TauS396. In contrast, the neuronal injury was improved using GSK-3ß inhibitor TWS119, which downregulated amyloid-ß/p-Taus396 phosphorylation by enhancing ERK1/2T202/Y204 and AktS473 phosphorylation. Our findings imply that the neurons were under stress and that the inactivation of the GSK3ß could alleviate this defect.

Therapeutic Effect of α-MSH in Primary Cultured Orbital Fibroblasts Obtained from Patients with Thyroid Eye Disease.

Inflammation, hyaluronan production, and adipogenesis are the main pathological events leading to thyroid eye disease (TED). α-Melanocytemelanocyte-stimulating hormone (α-MSH) is a well-known tridecapeptidetreatment for several inflammatory disorders including sepsis syndrome, acute respiratory distress syndrome, rheumatoid arthritis, and encephalitis. Here, we investigated the effect of α-MSH treatment on TED. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Lactate Dehydrogenase (LDH) assays were performed to analyze the effect of α-MSH on cell viability and it's toxicity. Using primary cultures of orbital fibroblasts from TED patients and non-TED as control, we examined the effects of α-MSH on proinflammatory cytokine production induced by interleukin (IL)-1ß, further analyzed by real-time reverse transcription-polymerase chain reaction (qPCR) and western blotting. Immunofluorescence staining assay and qPCR were performed to examine proopiomelanocortin (POMC) expression, the upstream neuropeptide of α-MSH in TED patients and non-TED control. Treatment with non-cytotoxic concentrations of α-MSH resulted in the dose-dependent inhibition of mRNA and protein levels (p < 0.05) for IL-1ß-induced inflammatory cytokines: IL-6, IL-8, MCP-1, ICAM-1, and COX-2. The expression of POMC mRNA and protein were significantly higher in TED patients compared to non-TED control (p < 0.05). Our data show significant inhibitory effects of α-MSH on inflammation, POMC production in orbital fibroblasts. At present, this is the first in vitro preclinical evidence of α-MSH therapeutic effect on TED. These findings indicate that POMC and α-MSH may play a role in the immune regulation of TED and can be a potential therapeutic target.

3H-1,2-Dithiole-3-Thione Protects Lens Epithelial Cells against Fructose-Induced Epithelial-Mesenchymal Transition via Activation of AMPK to Eliminate AKR1B1-Induced Oxidative Stress in Diabetes Mellitus.

Studies demonstrated that the receptor of advanced glycation end products (RAGE) induced epithelial-mesenchymal transition (EMT) formation in the lens epithelial cells (LECs) of diabetic cataracts. This work investigated how 3H-1,2-dithiole-3-thione (D3T) reduces EMT formation in LECs of the fructose-induced diabetes mellitus (DM). LECs were isolated during cataract surgery from patients without DM or with DM. In a rat model, fructose (10% fructose, eight weeks) with or without D3T (10 mg/kg/day) treatment induced DM, as verified by blood pressure and serum parameter measurements. We observed that the formation of advanced glycation end products (AGEs) was significantly higher in epithelial human lens of DM (+) compared to DM (-) cataracts. Aldose reductase (AKR1B1), AcSOD2, and 3-NT were significantly enhanced in the rat lens epithelial sections of fructose-induced DM, however, the phosphorylation level of AMPKT172 showed a reversed result. Interestingly, administration of D3T reverses the fructose-induced effects in LECs. These results indicated that AMPKT172 may be required for reduced superoxide generation and the pathogenesis of diabetic cataract. Administration of D3T reverses the fructose-induced EMT formation the LECs of fructose-induced DM. These novel findings suggest that the D3T may be a candidate for the pharmacological prevention of cataracts in patients with DM.

The effectiveness comparisons of eugenosedin-A, glibenclamide and pioglitazone on diabetes mellitus induced by STZ/NA and high-fat diet in SHR.

OBJECTIVES: Eugenosedin-A (Eu-A), an adrenergic and serotonergic antagonist, is known to have anti-metabolic syndrome effects. In this study, we evaluated its protective effects against diabetes mellitus (DM) in spontaneous hypertensive rats (SHR) and compared it with two anti-diabetes medications, glibenclamide (Gli) and pioglitazone (Pio). METHODS: We divided 10-week-old SHRs into five groups: a control group fed a normal diet; an untreated DM group induced by injecting the SHRs with STZ/NA and feeding them a high-fat diet (HFD); and three treated groups (after giving STZ/NA and HFD) gavage given with Eu-A, Gli or Pio (5 mg/kg per day) for 4 weeks. KEY FINDINGS: The untreated DM group weighed less and had hyperglycaemia, hypoinsulinemia and hyperlipidemia. They were also found to have aberrant glucose-dependent insulin pathways, glucose metabolism and lipid synthesis proteins, while the controls did not. Eu-A, Gli and Pio ameliorated the above biochemical parameters in the treatment groups. Eu-A and Pio, but not Gli, improved hypertension and tachycardia. CONCLUSIONS: Taken together, Eu-A ameliorated DM, hypertension and tachycardia by improving glucose, lipid homeostasis and anti-adrenergic, serotonergic activities. We concluded that Eu-A could be used in the development of an effective agent for controlling DM and its complications.

CX3CR1-microglia mediates neuroinflammation and blood pressure regulation in the nucleus tractus solitarii of fructose-induced hypertensive rats.

BACKGROUND: Inflammation is a common pathophysiological trait found in both hypertension and cardiac vascular disease. Recent evidence indicates that fractalkine (FKN) and its receptor CX3CR1 have been linked to inflammatory response in the brain of hypertensive animal models. Here, we investigated the role of CX3CR1-microglia in nitric oxide (NO) generation during chronic inflammation and systemic blood pressure recovery in the nucleus tractus solitarii (NTS). METHODS: The hypertensive rat model was used to study the role of CX3CR1-microglia in NTS inflammation following hypertension induction by oral administration of 10% fructose water. The systolic blood pressure was measured by tail-cuff method of non-invasive blood pressure. The CX3CR1 inhibitor AZD8797 was administered intracerebroventricularly (ICV) in the fructose-induced hypertensive rat. Using immunoblotting, we studied the nitric oxide synthase signaling pathway, NO concentration, and the levels of FKN and CX3CR1, and pro-inflammatory cytokines were analyzed by immunohistochemistry staining. RESULTS: The level of pro-inflammatory cytokines IL-1ß, IL-6, TNF-α, FKN, and CX3CR1 were elevated two weeks after fructose feeding. AZD8797 inhibited CX3CR1-microglia, which improved the regulation of systemic blood pressure and NO generation in the NTS. We also found that IL-1ß, IL-6, and TNF-α levels were recovered by AZD8797 addition. CONCLUSION: We conclude that CX3CR1-microglia represses the nNOS signaling pathway and promotes chronic inflammation in fructose-induced hypertension. Collectively, our results reveal the role of chemokines such as IL-1ß, IL-6, and TNF-α in NTS neuroinflammation with the involvement of FKN and CX3CR1.

Vitamin D Attenuates Loss of Endothelial Biomarker Expression in Cardio-Endothelial Cells.

Vitamin D is associated with cardiovascular health through activating the vitamin D receptor that targets genes related to cardiovascular disease (CVD). The human cardiac microvascular endothelial cells (HCMECs) were used to develop mechanically and TGF-ß1-induced fibrosis models, and the rat was used as the isoproterenol (ISO)-induced fibrosis model. The rats were injected with ISO for the first five days, followed by vitamin D injection for the consecutive three weeks before being sacrificed on the fourth week. Results showed that mechanical stretching reduced endothelial cell marker CD31 and VE-cadherin protein expressions, as well as increased α-smooth muscle actin (α-SMA) and fibronectin (FN). The transforming growth factor-ß1 (TGF-ß1) reduced CD31, and increased α-SMA and FN protein expression levels. Vitamin D presence led to higher protein expression of CD31, and lower protein expressions of α-SMA and FN compared to the control in the TGF-ß1-induced fibrosis model. Additionally, protein expression of VE-cadherin was increased and fibroblast-specific protein-1 (FSP1) was decreased after vitamin D treatment in the ISO-induced fibrosis rat. In conclusion, vitamin D slightly inhibited fibrosis development in cell and animal models. Based on this study, the beneficial effect of vitamin D may be insignificant; however, further investigation of vitamin D's effect in the long-term is required in the future.

AKR1B1-Induced Epithelial-Mesenchymal Transition Mediated by RAGE-Oxidative Stress in Diabetic Cataract Lens.

PURPOSE: Cataracts are a major cause of visual acuity deterioration in diabetes mellitus (DM) in developed and developing countries. Studies have demonstrated that overproduction of AKR1B1 and receptor for advanced glycation end products (RAGE) plays a major role in the pathogenesis of diabetic cataracts, but it is unclear whether the prevalence of diabetic cataracts is related to epithelial-mesenchymal transition (EMT) in lens epithelial cells. This study aimed to analyze the role of EMT in cataract formation of DM patients. METHODS: Immunofluorescence and immunohistochemistry assays were used to estimate AKR1B1, RAGE, AMPK, and EMT levels in epithelial human lens of DM or non-DM cataracts. RESULTS: Immunohistochemical staining demonstrated that pathologic phases and N-cadherin expression levels were significantly higher in epithelial human lens of DM (+) compared to DM (-) cataracts. Immunofluorescent staining showed that AKR1B1 and RAGE were significantly higher in epithelial human lens of DM (+) compared to DM (-) cataracts. Interestingly, acetyl superoxide dismutase 2 (AcSOD2) levels were significantly higher in DM patients' lens epithelial cells (LECs), whereas AMPKT172 phosphorylation was significantly increased in non-DM patients. This indicates that AMPKT172 might be related to superoxide reduction and diabetic cataract formation. CONCLUSIONS: Our results suggest that AKR1B1 overexpression can decrease AMPK activation, thereby increasing AcSOD2 and RAGE-induced EMT in epithelial human lens of DM cataracts. These novel findings suggest that AKR inhibitors may be candidates for the pharmacological prevention of cataracts in patients with DM.