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Hyperglycemia is a poorly controlled diabetic condition, affects about 70% of people all round the world. In the year 2015, about 41.5 crore people were diabetic and is expected to reach around 64.3 crore by the year 2040. Cardiovascular diseases (CVDs) are considered as one of the major risk factors that cause more than half of the death of diabetic patients and promote related comorbidities. Atherosclerosis and amyloidosis are the prime factors linked with CVDs. Apolipoprotein A-I (ApoA-I) of HDL has protective action against CVDs, participates in reverse cholesterol transport mechanism and lipid metabolism, but gets easily glycated under prolonged hyperglycemic aura, i.e. glycation. ApoA-I has a potent role in maintenance of glucose level, providing a compelling link between diabetes and CVDs. Increased protein glycation in people with diabetes promotes atherosclerosis, which might play possible role in promotion of protein aggregation by altering the protein structure and its conformation. Here, we intend to investigate the mechanistic behavior of ApoA-I under the menace of glycation and its impact on ApoA-I structure and function that possibly link with aggregation or amyloidosis. [ABSTRACT FROM AUTHOR]

Glycation refers to carbonyl group condensation of the reducing sugar with the free amino group of protein, which forms Amadori products and advanced glycation end products (AGEs). These AGEs alter protein structure and function by configuring a negative charge on the positively charged arginine and lysine residues. Glycation plays a vital role in the pathogenesis of metabolic diseases, brain disorders, aging, and gut microbiome dysregulation with the aid of 3 mechanisms: (i) formation of highly reactive metabolic pathway-derived intermediates, which directly affect protein function in cells, (ii) the interaction of AGEs with its associated receptors to create oxidative stress causing the activation of transcription factor NF-κB, and (iii) production of extracellular AGEs hinders interactions between cellular and matrix molecules affecting vascular and neural genesis. Therapeutic strategies are thus required to inhibit glycation at different steps, such as blocking amino and carbonyl groups, Amadori products, AGEs-RAGE interactions, chelating transition metals, scavenging free radicals, and breaking crosslinks formed by AGEs. The present review focused on explicitly elaborating the impact of glycation-influenced molecular mechanisms in developing and treating noncommunicable diseases. [ABSTRACT FROM AUTHOR]

The influence of advanced glycation end products (AGEs) in the biological processes contribute to the life-changing complications such as progression of cancer, diabetes and other chronic disorders. The receptor of AGEs while interacting with its ligands causes a never-ending irregularity in the cell-signaling communication. Hence, AGEs are considered as an important link between progression and contribution to cancer. This study focuses on the presence and/or absence of oxidative and glycative stress in the serum samples of various cancer patients. During analysis of the early and intermediate glycation product in cancer patient's sera, our result indicates an increasing trend of both the adducts as compared to normal healthy subjects. Similarly, one of the AGEs i.e., carboxymethyllysine was found to be enhanced in cancer sera as compared to NHS. The binding characteristics of circulating auto-antibodies in cancer patient's sera against human serum albumin (HSA)-AGEs were assessed through ELISA and furthermore, the maximum percent inhibition against HSA-AGEs was observed as 57–63%, 46–62% and 42–64% in prostate cancer, lung cancer and head and neck cancer. Hence, our result successfully assisted the presence of AGEs in all the cancer patient's sera though it is not clear which specific cancer is more potent to AGEs. [ABSTRACT FROM AUTHOR]

Glycation of biological macromolecules, due to hyperglycemia, promotes the formation of advanced glycation end products (AGEs). It is accelerated in diabetic patients and is responsible for the pathophysiology and progression of diabetes. Previous reports have shown that amount of AGEs formation and glycation-induced structural damage is higher in hemoglobin (Hb) than other proteins present in blood. In our previous study, we have shown structural changes in Hb by D-ribose which may result into the generation of immunogenic neo-epitopes. Thus, we hypothesized that D-ribose induced structural perturbations in Hb, could result in the formation of neo-epitopes which may provoke an auto-immune response and may also be involved in the immuno-pathogenesis of diabetes type-2 associated complications. Therefore, in the current study, we analyzed the prevalence of autoantibodies in diabetic patient's sera against D-ribose glycated-Hb by direct binding and competitive ELISA. Direct binding ELISA confirmed that autoantibodies in diabetic patients exhibit significantly high binding with D-ribose glycated-Hb as compared to its native form. The antigen binding specificity of these antibodies was also screened by competitive inhibition ELISA. We also used D-glucose glycated-Hb as a positive control to detect the presence of auto-antibodies by direct binding and inhibiton ELISA. We found that D-glucose glycated-Hb binds with T2DM samples but the affinity to binding is lower than D-ribose glycated-Hb. The overall findings of this study suggest the prevalence of circulating autoantibodies against D-ribose glycated-Hb in diabetic patients and thus, the level of these autoantibodies may be used as biomarker for progression of diabetes. [ABSTRACT FROM AUTHOR]

Glycation is the result of covalent bonding of a free amino group of biological macromolecules with a reducing sugar, which results in the formation of a Schiff base that undergoes rearrangement, dehydration and cyclization to form a more stable Amadori product. The final products of nonenzymatic glycation of biomacromolecules like DNA, proteins and lipids are known as advanced glycation end products (AGEs). AGEs may be generated rapidly or over long times stimulated by distinct triggering mechanisms, thereby accounting for their roles in multiple settings and disease states. Both Schiff base and Amadori glycation products generate free radicals resulting in decline of antioxidant defense mechanisms and can damage cellular organelles and enzymes. This critical review primarily focuses on the mechanistic insight of glycation and the most probable route for the formation of glycation products and their therapeutic interventions. Furthermore, the prevention of glycation reaction using therapeutic drugs such as metformin, pyridoxamine and aminoguanidine (AG) are discussed with special emphasis on the novel concept of the bioconjugation of these drugs like, AG with gold nanoparticles (GNPs). At or above 10 mM concentration, AG is found to be toxic and therefore has serious health concerns, and the study warrants doing this novel bioconjugation of AG with GNPs. This approach might increase the efficacy of the AG at a reduced concentration with low or no toxicity. Using the concept of synthesis of GNPs with abovementioned drugs, it is assumed that toxicity of various drugs which are used at high doses can be minimized more effectively. [ABSTRACT FROM PUBLISHER]

Advanced glycation end-products (AGEs) are known to be mutagenic, diabetogenic and vascular disease risk factors. Methylglyoxal (MG) is a dicarbonyl species that reacts with biological macromolecule (proteins, DNA and lipids) to give AGEs. Nonenzymatic glycation of MG with lysine (Lys) in the presence of copper (Cu2+) is reported to generate reactive oxygen species (ROS) capable of causing DNA damage. We show that DNA modification in MG–Lys–Cu2+ system results in the generation of strand breaks, base modification, hyperchromicity and increased fluorescence intensity. Superoxide generation in the MG–Lys system was found to be significantly higher when compared with that in the MG and Lys alone. Moreover, d-penicillamine and pyridoxal phosphate significantly inhibited the formation of glycation products. The presence of a major DNA glycation adduct, N2-carboxyethyl-2′-deoxyguanosine (CEdG), was detected by high performance liquid chromatography (HPLC) and confirmed by nuclear magnetic resonance (NMR). As reported earlier, modified DNA (MG–Lys-Cu2+-DNA) was highly immunogenic in experimental animals. Furthermore, induced anti-MG–Lys–Cu2+–DNA antibodies were effective probe for detecting glycoxidative lesions in human genomic DNA of type I diabetes patients. Our results clearly imply that interaction of MG–Lys and Cu2+ leads to the formation of AGEs and also the production of potent ROS, capable of causing DNA damage, thereby playing an important role in diabetes mellitus. [ABSTRACT FROM AUTHOR]

Background Efficacy of Colistin the last line agent against infections due to multidrug-resistant (MDR) gram-negative pathogens, has been challenged when Liu et al. reported a plasmid-mediated gene, mcr-1 , in 2015. Thereby this plasmid-borne mcr has been reported in bacterial isolates worldwide taken from humans, animals, farms, foods, and the environment. The present work invesitigate the mcr gene among clinical isolates of Acinetobacter Baumannii at our tertiary referral hospital of India. Methods The study was conducted at Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India. MIC values for 100 consecutive non-duplicate MDR isolates of Acinetobacter were checked for Colistin. PCR amplification of mcr gene was performed followed by sequencing of the amplicons. Clinical features of patients infected with mcr positive isolates were unveiled. Clonal relatedness of these isolates was investigated by Pulsed-field gel electrophoresis (PFGE). The mcr-1 localization was checked by conjugation followed by PFGE southern hybridization. Results 20/100 (20%) isolates were colistin resistant with having MIC Values of more than 8≤ µg/mL. The 20 colistin resistances isolates were PCR positive for mcr-1 and had been assigned EMBL/GeneBank nucleotide accession numbers MH730099-MH730118. Oher antibiotic resistance gene like ESBL, NDM-1, VIM, and 16s rRNA methyl transferases like Arm A, rmtC, rmt F were also found in these isolates. Majority of these patients recovered from the infection (65%) after proper antibiotic therapy.The IS Apl1 transposable elements were not detected in these isolates. These isolates were found clonally unrelated when analyze by pulsed-field gel electrophoresis. The conjugation attempt to transfer mcr-1 to recipient's E. coli J53 failed, Southern hybridization showed that mcr-1 was found located on chromosome in multiple copies. Conclusion This is the first case of mcr-1 in a human clinical isolate in Acinetobacter Baumnnii from India. These findings highlight the vertical transferability of colistin resistance by mcr-1 gene in Acinetobacter Baumnnii with the association of known some unknown insertion sequence located on chromosome. Strategies required to contain their spread and evolution of such genes. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]