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Abstract: Glycation of biomolecules leads to the establishment of advanced glycation end products (AGEs), which have significant role in the pathophysiology of diabetes leading to disorders, such as atherosclerosis. Ribose appears to be the most reactive among the naturally occurring sugars and contribute significantly to the glycation reactions in vivo, however, no report has been published to discuss d-ribose induced glycation of low density lipoprotein (LDL). The present study initially focuses on the glycation of commercially available LDL using different concentrations of d-ribose for varied incubation time intervals. The structural perturbations induced in LDL were analyzed by UV–vis, fluorescence & circular dichroism spectroscopy, and thermal denaturation studies. The ketoamine moieties, carbonyl content and HMF content were also quantitated in native and glycated LDL. We report structural perturbations, increased carbonyl content, ketoamine moieties and HMF content in d-ribose induced glycated LDL (LDL-AGEs) as compared to native analogue. These results provide evidence that LDL-AGEs could interfere in normal physiological functions and might contribute in the initiation of diabetes induced atherosclerosis and other secondary cardiovascular problems in diabetic patients. Though ours is a preliminary study, we are sure it would open the topic for further studies. [Copyright &y& Elsevier]

Abstract: Aims: Glycation of proteins and DNA, results in the generation of free radicals causing structural modification of biomacromolecule. This leads to the generation of neo-antigenic epitopes having implication in diabetes mellitus. In this study, human placental DNA was glycated with fructose and its binding was probed with the serum antibodies from type 1 and 2 diabetes patients. Methods: Glycation was carried out by incubating DNA (10μg/ml) with fructose (25mM) for 5 days at 37°C. The induced structural changes in DNA were studied by spectroscopic techniques, thermal denaturation studies and agarose gel electrophoresis. Furthermore, binding characteristics of autoantibodies in diabetes (type 1 and 2) patients were assessed by direct binding and competitive ELISA. Results: DNA glycation with fructose resulted in single strand breaks, hyperchromicity in UV spectrum and increased fluorescence intensity. Thermal denaturation studies demonstrated the unstacking of bases and early onset of duplex unwinding. Type 1 diabetes patients exhibited enhanced binding with glycated DNA as compared to native form, while for type 2 diabetes only those with secondary complications (Nephropathy) showed higher binding. Conclusions: Glycation of DNA has resulted in structural perturbation causing generation of neo-antigenic epitopes that are better antigens for antibodies in diabetes patients. [Copyright &y& Elsevier]

Glycation initiates with the non-enzymatic reaction of amino group of proteins and lipoproteins by carbonyl group of sugar moiety and intermediates of glycative stress such as methylglyoxal (MG). The initial glycation leads to the formation of early glycation products (Amadori products) which undergo rearrangement, cyclization and dehydration to form advanced glycation end products (AGEs). The main objective of the present study is to investigate the non-enzymatic glycation of low density lipoprotein (LDL) by MG at different concentration and at increasing incubation time period in vitro . This modification may increase the formation of Amadori products and AGEs which are physico-chemically characterized with respect to the extent of LDL modification. Additionally, immunogenicity of native and MG modified LDL (MG-LDL) was probed in female rabbits in vivo . Immunogenicity of MG-LDL was found to be highly immunogenic, eliciting high titer immunogen-specific antibodies while native form of LDL is less immunogenic. Furthermore, the histopathology and immune-fluorescence studies suggest that the kidney section of immunized rabbits exhibit the presence of immune complex (MG-LDL-IgG) deposition in the glomerular basement membrane (GBM). [ABSTRACT FROM AUTHOR]

• Pinostrobin (PN) suppressed the growth and proliferation of lung cancer cells (A549). • PN induced apoptosis via intrinsic apoptosis pathway. • PN abrogated the cell cycle progression in A549 lung cancer cells. • PN downregulated notch signaling cascade in lung cancer. Pinostrobin (PN) is a dietary bioflavonoid naturally found in numerous medicinal plants. Even though the anticancer potential of flavonoids has been studied; however the molecular targets and the exact mechanism behind their apoptosis-inducing actions are not yet fully elucidated. The present study was aimed to investigate if PN could induce apoptosis in lung cancer A549 cells of human origin. PN reduced the proliferation of A549 cells in a dose-dependent manner. Induction of apoptosis was observed in PN-treated lung cancer cells as evident by DNA fragmentation and Annexin V positive cells. The PN induced reactive oxygen species (ROS) generation in A549 cells, leading to activation of key regulators of apoptosis such as Bax, Bad and Bcl2 as well as release of cytochrome c, and activation of the caspase cascade including caspase-9 and -3. Enhanced loss of Δψm, cytochrome c release and cleavage of caspase-3 & -9 strongly corroborated our findings. Furthermore, PN treatment of lung cancer cells arrested the cell cycle in G0/G1 phase, inhibited constitutive expression of Cyclin D1and CDK4 and induced the mRNA levels of p21Cip1. A dose-dependent decreased expression of Notch-1, Jagged-1 and Hes-1 were noted in PN treated A549 cells. These findings demonstrated that PN suppressed the growth of A549 cells via downregulating the Notch pathway. Thus, subsequent studies focusing on molecular mechanism of PN can pave path for anticancer drug design. [ABSTRACT FROM AUTHOR]

Glycation of biologically important macromolecules leads to the establishment of advanced glycation end products (AGEs) having significant role in the pathophysiology of various diseases. d -Ribose, is a highly reactive pentose sugar resulting in the rapid formation of AGEs. Formation of d -ribose derived glycated DNA and LDL has been previously demonstrated; however no comparative, extensive studies have been performed to assess the immunogenicity of d -ribose glycated calf thymus DNA (CT-DNA) and LDL. In the present study, the results showed that animals immunized with d -ribose modified CT-DNA and LDL induced antibodies as detected by direct binding and competition ELISA. The modified CT-DNA and LDL were found to be highly immunogenic, eliciting high titer immunogen-specific antibodies, while the native forms of DNA was almost non-immunogenic. The induced antibodies from modified CT-DNA and LDL exhibited wide range of heterogeneity in recognizing various nucleic acid conformers, DNA bases and amino acids. Furthermore, Serum antibodies from diabetes and diabetes atherosclerosis patients were screened for their binding to native CT-DNA, LDL and glycated CT-DNA, LDL. Glycated CT-DNA showed almost equivalent binding to both diabetes and diabetic atherosclerosis group while high recognition was observed when glycated LDL was used as an antigen. [ABSTRACT FROM AUTHOR]

Glycation of proteins results in structural alteration, functional deprivation, and generation of advanced glycation end products (AGEs). Reactive oxygen species (ROS) that are generated during in vivo autoxidation of glucose induces glycoxidation of intermediate glycation-adducts, which in turn give rise to aldehyde and/or ketone groups containing dicarbonyls or reactive carbonyl species (RCS). RCS further reacts non-enzymatically and starts the glycation-oxidation vicious cycle, thus exacerbating oxidative, carbonyl, and glycative stress in the physiological system. Glyoxal (GO), a reactive dicarbonyl that generates during glycoxidation and lipid peroxidation, contributes to glycation. This in vitro physicochemical characterization study focuses on GO-induced glycoxidative damage suffered by immunoglobulin G (IgG) and fibrinogen proteins. The structural alterations were analyzed by UV–vis, fluorescence, circular dichroism, and Fourier transform infrared (FT-IR) spectroscopy. Ketoamines, protein carbonyls, hydroxymethylfurfural (HMF), free lysine, free arginine, carboxymethyllysine (CML), and protein aggregation were also quantified. Structural perturbations, increased concentration of ketoamines, protein carbonyls, HMF, and malondialdehyde (MDA) were reported in glycated proteins. The experiment results also validate increased oxidative stress and AGEs formation i.e. IgG-AGEs and Fib-AGEs. Thus, we can conclude that AGEs formation during GO-mediated glycation of IgG and fibrinogen could hamper normal physiology and might play a significant role in the pathogenesis of diabetes-associated secondary complications. [ABSTRACT FROM AUTHOR]

In diabetes mellitus, hyperglycemia mediated non-enzymatic glycosylation of proteins results in the pathogenesis of diabetes-associated secondary complications via the generation of advanced glycation end products (AGEs). The focus of this study is to reveal the immunological aspects of methylglyoxal (MG) mediated glycation of fibrinogen protein. The induced immunogenicity of modified fibrinogen is analyzed by direct binding and inhibition ELISA. Direct binding ELISA confirmed that MG glycated fibrinogen (MG-Fib) is highly immunogenic and induces a high titer of antibodies in comparison to its native analog. Cross-reactivity and antigen-binding specificity of induced antibodies were confirmed by inhibition ELISA. The enhanced affinity of immunoglobulin G (IgG) from immunized rabbits' sera and MG glycated fibrinogen is probably the aftermath of neo-epitopes generation in the native structure of protein upon modification. Thus, we deduce that under the glycative stress, MG-mediated structural alterations in fibrinogen could induce the generation of antibodies which might serve as a potential biomarker in diabetes mellitus and its associated secondary disorders. • Non-enzymatic glycation is associated with the pathogenesis of diabetes mellitus. • The immunogenicity of modified fibrinogen is analyzed by direct binding and competitive/inhibition ELISA. • Direct binding ELISA infers that MG glycated fibrinogen is highly immunogenic and induces high titer of antibodies. • Cross reactivity and antigen binding specificity of induced antibodies were confirmed by competitive ELISA. [ABSTRACT FROM AUTHOR]

The study focuses on whether antigenic proteins encapsulated in biopolymeric nanoparticles can augment protective efficacy. Chitosan nanoparticles (ChN) were prepared by ionic gelation method and Culture Filtrate Proteins (CFP) - CFP-10 and CFP-21 of Mycobacterium tuberculosis (Mtb) were encapsulated in ChN. The binding efficiency of nanoparticles with CFP-10 and CFP-21 proteins was confirmed by UV-Spectrophotometer. The efficacy of nanoparticles-encapsulated antigenic proteins administered intraperitoneal against Mtb aerosol infection was evaluated in Balb/c mice. Protection study was done by bacterial counts [CFU]. CFP-10 and CFP-21 proteins primed cells demonstrated a Th1 bias T cell response in an ex vivo assay. ChN-CFP10 and ChN-CFP21 nanoparticles have both protective and therapeutic potential against Mtb. In the group of mice immunized with CHN-CFP-10 the number of colonies reduced significantly from day 15 to day 60. ChN-CFP-21 showed maximum protection in ChN-CFP-21 immunized mice. ChN-CFP-10 and ChN-CFP-21 clearly showed enhanced protection against Mtb. Chitosan nanoparticles encapsulated into antigenic proteins of Mycobacterium tuberculosis. (1) The chitosan nanoparticles (CHNP) were prepared by Inotropic gelation method. (2) Culture filtrate proteins (CFP) from Mycobacterium tuberculosis (Mtb) were encapsulated into the nanoparticles. (3) Female Balb/c mice were immunized with CFP-encapsulated nanoparticles via intraperitoneal routes thrice at an interval of three weeks. (4) Mice were exposed for 30 min in a Madison aerosol chamber, by nebulizing 5 ml of a bacterial suspension of H37Rv in 0.9% NaCl solution at a concentration of 2 × 106 bacilli/ml. (5) Mice were sacrificed 10- and 60-days post infection and Colony Forming Unit Assay (CFU) was performed. Unlabelled Image • Chitosan nanoparticles were prepared in the size range of ~250 to ~300nm • Having a zeta potential +41mV • Entrapment efficiency for CFP-10 ~16% and for CFP-21 ~18% • The FTIR studies indicated that the chitosan nanoparticles there was a distinct shift of the peak to 1564.03cm-1 due to the wagging of NH2 bond • The IFN-γ level demonstrated a Th1 biased T cell response in an ex vivo assay • The GST levels were lowered indicating oxidative on Day 7. • Enhanced GST levels was observed on day 21 indicated reduced or no oxidative stress. • Protection was induced in ChN- CFP-10 immunized mice as compared to CFP-10 per se. • Remarkably, in the group of mice immunized with ChN-CFP-10 the number of colonies reduced significantly from day15 to day 60. [ABSTRACT FROM AUTHOR]

Abstract Non-enzymatic glycation occurs rapidly which ultimately leads to the formation of advanced glycation endproducts (AGEs). These AGEs have shown to associated with the development of many diseases such as diabetes-mellitus. This study is focused on immunological characterization of glycated-Hb induced by d -ribose. Here, we analysed the immunogenicity of glycated-Hb by direct binding and competitive inhibition ELISA. Direct binding ELISA confirmed that glycated-Hb was highly immunogenic and induced high titre antibodies as compared to native-Hb. The antigen binding specificity and cross reactivity of these antibodies were also screened by competitive inhibition ELISA. The IgG from rabbit sera showed enhanced binding of glycated-Hb than native-Hb. Thus, it is possible that alterations in Hb induced by d -ribose could have generated highly immunogenic neoepitopes. Moreover, induced antibodies were also found to cross-react with other modified/native proteins. On the basis of the results of this study, we presume that this type of structural perturbations in Hb in vivo by d -ribose might take place in untreated diabetic condition that could induce such type of immunogenic auto-antibodies. Furthermore, increased level of these auto-antibodies could serve as a biomarker in diabetes and its progression. [ABSTRACT FROM AUTHOR]

Abstract Advanced glycation end-products (AGEs) can aggregate amid incessant inflammation, as may be available in patients with rheumatoid arthritis. d -Ribose reacts more promptly than glucose monosaccharide to the proteins and forms heterogeneous group of products known as AGEs. Obesity includes persons with provocative joint inflammation with increased lipid profile. Immunogenic evidences recommend a cross-sectional relationship between glycated LDL-Apo B100 and inflammation. The point of this examination was to look at the connection between d -ribose glycated ApoB100 (ApoB100-AGE) with obesity and rheumatoid arthritis. The binding specificity of auto-antibodies against ApoB100-AGE antigen present in obesity and rheumatoid arthritis patient's serum were inspected by direct binding and was further established by competitive inhibition ELISA. In the present study, hydroxyl radical, superoxide radical, ketoamine moieties, hydroxyl-methyl furfural (HMF) and carbonyl substances were evaluated in the patients' serum via respective specific methods. The prevalence of auto-antibodies against ApoB100-AGE antigen was recorded to be 58% and 52.86% from obese and rheumatoid arthritis patient respectively in contrast to its native analogue (P < 0.001). Moreover, the autoantibodies present in obese and arthritis patients were found to be highly specific towards ApoB100-AGE as confirmed by inhibition ELISA. Highlights • The keto-amine moieties, HMF and carbonyl substance were higher in obese and Arthritic patient sera. • High degree of specificity in 80% obese and 73% rheumatoid sera against Apo-B100-AGE-IgG was obtained. • In obese and Rheumatoid sera, inhibition with glycated ApB 100 was 87% and 64% respectively. [ABSTRACT FROM AUTHOR]

Non-enzymatic glycation mediated advanced glycation end products (AGEs) generation results in the pathogenesis of diabetic complications and atherosclerotic cardiovascular disease (ASCVD) which is greatly influenced by 3-hydroxy-3-methyl-glutaryl Co-A reductase (HMG-R) activity. HMG-R inhibitors, statins, are well known for reducing mortality and morbidity of ASCVD in patients with diabetes due to their pleiotropic effects independent of cholesterol lowering. Due to distinct chemical structures, various statins may play important role in the inhibition of AGEs mediated pathologies. Herein, we evaluated the anti-glycating potential of atorvastatin (AT), rosuvastatin (RT), pitavastatin (PT), fluvastatin (FT), simvastatin (ST) alone as well in combination with ezetimibe (EZ) and tocotrienol (TT) against d -ribose mediated BSA and LDL glycation by various physicochemical approaches. Our data suggested that AT, TT, RT, EZ, EZ-AT, and EZ-RT were able to substantially inhibit the AGEs formation via modulation of hyperchromicity, fluorogenic AGEs, % contribution of α-helix and β-sheets to protein secondary structure, amide-I band stretching, carbonyl and HMF content in Gly-BSA as well as Gly-LDL. On the basis of above findings, we concluded that HMG-R inhibitors and TT, alone or in combination with EZ, may be established as terrific therapeutic agents for the patients suffering from AGEs induced diabetic cum ASCVD complications. [ABSTRACT FROM AUTHOR]

Glycation of biological macromolecule leads to the establishment of advanced glycation end products (AGEs) having implications in metabolic disorders. d ‑ribose appears to be the most reactive among the naturally occurring sugars and contribute significantly to the glycation reactions in vivo , however, no report have been published yet to discuss d ‑ribose induced glycation of hemoglobin (Hb). Therefore, the present study was designed to investigate d ‑ribose induced glycoxidative damage to Hb protein. Briefly, the commercially available Hb was glycated with d ‑ribose for varying time intervals. The structural perturbation induced in glycated Hb (GHb) was confirmed by biophysical techniques viz. , UV–visible, fluorescence spectroscopy, circular dichroism, Fourier transform infra-red spectroscopy, dynamic light scattering, MALDIthermal denaturation by UV–visible spectrophotometer and DSC. Biophysical techniques confirm the secondary and tertiary structural perturbation in GHb as compared to native Hb. The values of carbonyl content, hydroxy methyl furfural, thiobarbituric acid reactive substance and nitro blue tetrazolium were found to be increased and free lysine and free arginine content were decreased in the GHb due to structural change. Thus, results of this study have established that glycation with d ‑ribose lead to the structural changes in the native Hb which might play an important role in pathophysiology metabolic diseases. [ABSTRACT FROM AUTHOR]

The diterpene lactone andrographolide, isolated from Andrographis paniculata, has been proven to possess several important protective biological activities, including antioxidant, anti-inflammatory, immunomodulatory, antiseptic, antimicrobial, cytotoxic, hypolipidemic, cardioprotective, hepatoprotective, and neuroprotective effects. In addition, it has been reported to play a therapeutic role in the treatment of major human diseases, such as Parkinson's disease, rheumatoid arthritis, and colitis. This systematic review aims to highlight andrographolide as a promising agent in cancer treatment. To this purpose, a number of databases were used to search for the cytotoxic/anticancer effects of andrographolide in pre-clinical and clinical studies. Among 1703 identified literature articles, 139 were included in this review; 109 were investigated as non-clinical, whereas 24, 3, and 3 were pre-clinical, clinical, and non-pre-clinical trials, respectively. Among the model systems, cultured cell lines appeared as the most frequently (79.14%) used, followed by in vivo models using rodents, among others. Furthermore, andrographolide was found to exert cytotoxic/anticancer effects on almost all types of cell lines with the underlying mechanisms involving oxidative stress, cell cycle arrest, anti-inflammatory and immune system mediated effects, apoptosis, necrosis, autophagy, inhibition of cell adhesion, proliferation, migration, invasion, anti-angiogenic activity, and other miscellaneous actions. After careful consideration of the relevant evidence, we suggest that andrographolide can be one of the potential agents in the treatment of cancer in the near future. [ABSTRACT FROM AUTHOR]

Human serum albumin is playing an increasing role as a drug carrier in clinical settings. Biotin molecules are often used as suitable tags in targeted anti-tumor drug delivery systems. We report on the synthesis and properties of a new multimodal theranostic conjugate based on an anti-cancer fluorinated nucleotide conjugated with a biotinylated dual-labeled albumin. Interestingly, in vitro and in vivo study revealed stronger anti-tumor activity of the non-tagged theranostic conjugate than that of the biotin-tagged conjugate, which can be explained by decreased binding of the biotin-tagged conjugate to cellular receptors. Our study sheds light on the importance of site-specific albumin modification for the design of albumin-based drugs with desirable pharmaceutical properties. [ABSTRACT FROM AUTHOR]

We report on the synthesis and properties of a new multimodal theranostic conjugate based on an anticancer fluorinated nucleotide conjugated with a dual-labeled albumin. A fluorine-labeled homocysteine thiolactone has been used as functional handle to synthesize the fluorinated albumin and couple it with a chemotherapeutic agent 5-trifluoromethyl-2′-deoxyuridine 5′-monophosphate (pTFT). The conjugate allows for direct optical and 19 F magnetic resonance cancer imaging and release of the drug upon addition of glutathione. Interestingly, the pTFT release from albumin conjugate could only be promoted by the increased acidity (pH 5.4). The in vitro study and primary in vivo investigations showed stronger antitumor activity than free pTFT. [ABSTRACT FROM AUTHOR]

Aims Glycation of proteins leads to the formation of advanced glycation end products (AGEs, which have significant role in the pathophysiology of diabetes complications. d -ribose appears to be the most reactive among the naturally occurring sugars and contribute significantly to the generation of AGEs. Glycation also results in the generation of free radicals causing structural modification which leads to the generation of neoantigenic epitopes. The aim of the present study was to investigate whether LDL modification results in auto-antibodies formation against its glycated conformer in diabetes and atherosclerosis patients. Methods The binding characteristics of circulating auto-antibodies in patients against native and modified LDL were assessed. T2D ( n = 105), ATH ( n = 106) and T2D-ATH patients ( n = 72) were examined by direct binding ELISA as well as inhibition ELISA, compared with healthy ag e -matched controls ( n = 50). Furthermore, ketoamine moieties, HMF and carbonyl content were also estimated in these patient's and healthy subjects. Key findings High degree of specific binding was observed by 41.91% of T2D, 54.72% of ATH and 70.83% T2D-ATH patient's sera towards d -ribose glycated LDL, in comparison to its native analog ( P < 0.05). Normal human sera showed negligible binding with either antigen. Competitive inhibition ELISA reiterates the direct binding results. The higher concentration of HMF, ketoamine and carbonyl content was observed in patient's sera than healthy subjects. Significance LDL glycation results in structural perturbation causing generation of neoantigenic epitopes that are better antigens for antibodies in T2D, ATH and T2D-ATH patients where T2D-ATH subjects showed higher prevalence in auto-antibodies against ribosylated LDL. [ABSTRACT FROM AUTHOR]

Non-enzymatic glycation is the addition of a free carbonyl group of a reducing sugar to the free amino groups of proteins, which results in the formation of early and advanced glycation end-products (AGEs). Glycation reaction is profoundly associated with diabetes and its secondary complications, such as nephropathy and neuropathy. Glyoxal is a carbonyl species that reacts rapidly with the free amino groups of proteins to form AGEs. While the formation of AGEs with various glycating agents has previously been demonstrated, no extensive studies have been conducted to assess the role of quercetin in all three stages of glycation (early, intermediate and late). In this study, we report the glycation of HSA (human serum albumin) and its characterization by several spectroscopic techniques. Furthermore, inhibition of products at all stages of glycation was studied by various assays. Spectroscopic analysis suggests structural perturbations in the HSA macromolecule as a result of modification, which might be due to the generation of free radicals and the formation of AGEs. Inhibition in the formation of glycation has established that quercetin is a better and a more potent antiglycating agent than aminoguanidine at all stages of glycation. [ABSTRACT FROM AUTHOR]

Glyoxal, methylglyoxal and 3-deoxyglucosones are reactive dicarbonyl compounds, which transform free amino groups of proteins and lipoproteins macromolecule into advanced glycation end-products (AGEs). AGEs play a significant role in the pathophysiology of aging and diabetic complications because of their genotoxic effect. Glyoxal also reacts with free amino group of nucleic acids resulting in the formation of DNA–AGEs. The present study reports the genotoxicity and immunogenicity of AGEs formed by Glyoxal–Arginine–Fe 3+ (G–Arg–Fe 3+ ) system as a glycating agent. Immunogenicity of native and G–Arg–Fe 3+ –DNA was probed in female rabbits. Immunofluorescence suggests the presence of immune complex deposition in the kidney section of immunized rabbits. Spectroscopic analysis and melting temperature indicates the structural modification in the human DNA. The modified human DNA is found to be highly immunogenic, whereas unmodified form was simply non-immunogenic. This study shows the presence of auto-antibodies against G–Arg–Fe 3+ modified human DNA in the sera of diabetes type 1 and in few cases type 2 patients due to secondary complications of nephropathy. The glyco-oxidative lesions have also been detected in the lymphocyte DNA isolated from patients having type 1 and type 2 diabetes. The results show structural perturbations generating new epitopes in G–Arg–Fe 3+ –DNA rendering it pretty immunogenic. [ABSTRACT FROM AUTHOR]

Abstract: The non-enzymatic addition of carbonyl group of sugar moiety to the amino group of DNA macromolecule leads to the formation of early glycation products (Amadori products) which undergoes rearrangement, cyclization and dehydration to form advanced glycation end products (AGEs). While the formation of glucose derived glycated DNA has been previously demonstrated, however no extensive studies have been performed to assess the glycation of DNA using d-ribose as glycating agent. d-ribose, an important monosaccharide, is a highly reactive pentose sugar which results in the rapid formation of AGEs. To the best of our knowledge, this is the first study to characterize the d-ribose-induced changes in calf thymus DNA, as well as calf thymus DNA Amadori and calf thymus DNA-AGEs. The main objective of the study is to investigate the non-enzymatic glycation of calf thymus DNA by using different concentrations of d-ribose at increasing time period. The obtained Amadori products, AGEs were characterized with respect to the extent of DNA strand break and base modifications. Additionally, their nitroblue tetrazolium (NBT) reduction assay, absorbance, agarose gel electrophoresis, fluorescence, circular dichroism (CD) and thermal denaturation (T m) characteristics were extensively studied. We found significant changes in the modification of DNA and in AGE-specific fluorescence, using different concentration of modifiers (d-ribose). The results provide the mechanistic insight of d-ribose induced glycation in calf thymus DNA. The bio-availability of d-ribose makes this carbonyl species quite reactive and damaging, therefore having direct implication in diabetes. This is the preliminary study done on d-ribose glycation and warrants further study to probe the role ribose-DNA glycation in different disease state including diabetes. [Copyright &y& Elsevier]

Advanced glycation end products (AGEs) trigger intracellular reactive oxygen species (ROS) generation, activation of receptor for AGEs (RAGE) expression/functionality and RAGE-associated signalling pathways which influence the diabetic-cum-atherosclerotic complications, whereas, the atherosclerosis progression is greatly influenced by hepatic β-Hydroxy-β-methyl-glutaryl-Co-A reductase (HMG-R) activity. The present report was premeditated to uncover the regulatory role of HMG-R inhibitors and ezetimibe (EZ) in attenuating the LDL-AGEs-induced pathogenicity via targeting cellular-ROS and RAGE-associated signalling in HEK-293 cells. The MTT assay was used to assess either the cytotoxic or cytoprotective impact of each HMG-R inhibitors, EZ, and LDL-AGEs, whereas, quantification of ROS was performed by DCFDA method. The qRT-PCR was used to detect the mRNA level of RAGE, neuropilin-1 (NRP-1) and other RAGE-associated genes like MMP-2, NF-κB, and TGFβ-1. The HMG-R inhibitors do not exert any cytotoxicity in HEK-293 cells, whereas, and LDL-AGEs negatively affected the cell viability of HEK-293 cells. However, viability of LDL-AGEs-treated HEK-293was markedly retained after simultaneous treatment with our test inhibitors. Further, DCFDA staining showed that LDL-AGEs-induced ROS was also suppressed upon treatment with our test inhibitors in HEK-293 cells. qRT-PCR analysis reflected that these inhibitors suppress the RAGE, NF-κB, TGFβ-1, and MMP-2 expression, whereas, the NRP-1 was up-regulated by these compounds in LDL-AGEs-exposed HEK-293 cells. The above pharmacological effects signify that HMG-R inhibitors and EZ (alone or in combination) may implied in the treatment of AGEs-induced oxidative stress and tissue damage in diabetic complications via targeting intracellular-ROS, NRP-1 functionality and RAGE-associated genes i.e. NF-κB, TGFβ-1, and MMP-2. Unlabelled Image [ABSTRACT FROM AUTHOR]