Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the effects of advanced glycation end products (AGEs), which are known to accumulate in patients with diabetes, autoimmune diseases, or those who smoke, on embryonal development. Pronuclear (PN) embryos were obtained by flushing the fallopian tubes of rats after superovulation and mating. The cleavage rate and blastocyst yield were evaluated at 24, 72, 96, and 120 h of culture. Glyoxal, an AGE-forming aldehyde, suppressed embryonal development at every stage from PN to blastocyst in a concentration-dependent manner. The cleavage rate of the embryo was also signifi cantly decreased by treatment with glyoxal at concentrations of 1 mM or higher. The blastocyst yield was significantly decreased by treatment with glyoxal at concentrations of 0.5 mM or higher. N-acetyl-L-cysteine (L-NAC) at 1 mM significantly suppressed the glyoxal-induced embryonal toxicity. BSA-AGEs at 5 microg/ml or higher concentration signifi cantly reduced the cleavage rate and blastocyst yield compared to those for BSA-treated embryos. L-NAC at 1 mM significantly suppressed BSAAGE-induced embryonal toxicity. Because AGEs are embryo-toxic, AGE contamination may influence the pregnancy rate of in vitro fertilization and embryo transfer. AGEs, which are increased in women under pathological conditions, may also be involved in their infertility.
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PMID:Adverse effects of advanced glycation end products on embryonal development. 1846 85

The first synthesis of an optically pure (2R,3R,4S)-hydantoin 2, analogue of (2S,3R,4S)-4-hydroxyisoleucine, was achieved in two steps in un-optimized 35% overall yield from previously reported aldehyde synthon 1. (2R,3R,4S)-Hydantoin is stable at acidic pH. This solves the major drawback of (2S,3R,4S)-4-hydroxyisoleucine that easily cyclizes into inactive lactone. Furthermore, (2R,3R,4S)-hydantoin stimulates the insulin secretion by 150% at 25microM compared with 4-hydroxyisoleucine and insulin secretagogue drug repaglinide. In view of its stability and biological activity, (2R,3R,4S)-hydantoin represents a good candidate for type-2 diabetes management and control.
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PMID:Synthesis of hydantoin analogues of (2S,3R,4S)-4-hydroxyisoleucine with insulinotropic properties. 1862 29

Aloe greatheadii var. davyana (Asphodelaceae) is used among rural South African communities to treat arthritis, skin cancer, burns, eczema, psoriasis, digestive problems, high blood pressure and diabetes, despite very little supporting scientific evidence. Due to increased interest by both the scientific community and industry regarding the medicinal uses of this plant species, we identified, quantified and compared the phytochemical contents and antioxidant capacities of two extracts of A. greatheadii; a leaf gel extract (LGE) and a 95 % aqueous ethanol leaf gel extract (ELGE), using various modified extraction procedures, GC-MS and spectrophotometry. Apart from extensively characterizing this medicinal plant with regards to its organic acid, polyphenols/phenolic acid, alcohol, aldehyde, ketone, alkane, pyrimidine, indole, alkaloid, phytosterol, fatty acid and dicarboxylic acid contents and antioxidant capacities, we describe a modified extraction procedure for the purpose of general phytochemical characterization, and compare this to a 95 % aqueous ethanol extraction technique. From the results it is clear that A. greatheadii contains a variety of compounds with confirmed antioxidant capacity and other putative health benefits (such as blood glucose, cholesterol and cortisol lowering properties) relating to the prevention or treatment of diabetes, cardiovascular disease, cancer and hypertension. The results also indicate that separate ethyl acetate/diethyl ether and hexane extractions of the LGE, better serve for general phytochemical characterization purposes, and 95 % aqueous ethanol extraction for concentrating selective groups of health related compounds, hence justifying its use for biological in vivo efficacy studies.
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PMID:Phytochemical contents and antioxidant capacities of two Aloe greatheadii var. davyana extracts. 1883 Jan 48

The primary functional role of collagen is as a supporting tissue and it is now established that the aggregated forms of the collagen monomers are stabilised to provide mechanical strength by a series of intermolecular cross-links. In order to understand the mechanical properties of collagen, it is necessary to identify and quantitatively determine the concentration of the cross-links during their changes with maturation, ageing and disease. These cross-links are formed by oxidative deamination of the epsilon-amino group of the single lysine or hydroxylysine in the amino and carboxy telopeptides of collagen by lysyl oxidase, the aldehyde formed reacting with a specific lysine or hydroxylysine in the triple helix. The divalent Schiff base and keto-amine bonds so formed link the molecules head to tail and spontaneously convert during maturation to trivalent cross-links, a histidine derivative and cyclic pyridinolines and pyrroles, respectively. These latter bonds are believed to be transverse inter-fibrillar cross-links, and are tissue rather than species specific. We describe the determination of these cross-links in detail.Elastin is also stabilised by cross-linking based on oxidative deamination of most of its lysine residues to yield tetravalent cross-links, desmosine and iso-desmosine, the determination of which is also described.A second cross-linking pathway occurs during ageing (and to a greater extent in diabetes mellitus) involving reaction with tissue glucose. The initial product glucitol-lysine can be determined as furosine and pyridosine, and determination of advanced glycation end-products believed to be cross-links, such as pentosidine, are also described.
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PMID:quantitative determination of collagen cross-links. 1924 1

We investigated the effects of the in vivo administration of thymosin alpha-1 (Talpha-1) on streptozotocin (STZ)-induced pancreatic lesions and diabetes. Mice were randomly divided into four experimental groups: normoglycemic control, STZ-treated, STZ plus 0.1 microg/kg body weight/day Talpha-1-treated, and STZ plus 1 microg/kg/day Talpha-1-treated. Blood glucose was assayed periodically, and serum insulin was determined at the end of the experiment using the ELISA Kit. Aldehyde fuchsin staining was used for histopathological examination of the pancreas. Parameters for oxidative stress were measured with pancreatic malondialdehyde (MDA) level, glutathione (GSH) content and enzymatic activities of superoxide dismutase and catalase. Fourteen days after the initiation of Talpha-1 treatment and up to day 35 when the treatment was stopped, both of the two STZ and Talpha-1-co-treated mouse groups had significant lower levels of blood glucose than the STZ-treated but Talpha-1-untreated mice, although both remained higher than that of the normoglycemic controls. At the end of the Talpha-1 treatment, the serum insulin level for STZ-treated mice receiving 1 microg/kg/day Talpha-1 for 35 days was 2-fold (P<0.001) as much as that of the Talpha-1-untreated STZ-diabetic mice, although not completely restored to the normal level. Pancreatic aldehyde fuchsin staining showed that STZ treatment caused significant pancreatitis, islet atrophy, and a significant reduction in the number of pancreatic beta cells. These histological lesions, however, were significantly alleviated by 1 microg/kg/day Talpha-1 treatment for 35 days. Furthermore, compared with the Talpha-1- untreated STZ-diabetic mice, the pancreatic GSH level of the 1 microg/kg/day Talpha-1-treated STZ-induced mice was 1.92-fold that of the untreated STZ-induced mice (P<0.01), whereas the pancreatic MDA level was only 81.9% that of the untreated STZ-diabetic mice (P<0.05). Together these results demonstrate that co-administration of Talpha-1 leads to significant protection against STZ-induced pancreatic damage and diabetes, and part of the protection might be achieved through enhancing pancreatic antioxidative capability.
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PMID:Intraperitoneal co-administration of thymosin alpha-1 ameliorates streptozotocin-induced pancreatic lesions and diabetes in C57BL/6 mice. 1936 Mar 17

Glycolaldehyde (GA) is a highly reactive aldehyde that can be generated during inflammation and hyperglycemia. It can react with arginine and lysine residues impairing protein function. As inflammation and diabetes present haemostatic dysfunction, we hypothesized that GA could participate in this process. The aim of this study was to investigate if plasma incubated in the presence of GA presents alteration in the coagulation process. We also aimed to evaluate the role of fibrinogen in GA-induced haemostatic dysfunction. For this purpose, plasma and fibrinogen were each incubated separately, either in the presence or absence of 1 mM GA for 8 and 4 h, respectively. After that, plasma coagulation and fibrin polymerization kinetics were recorded, as well as the kinetic of plasma clot digestion and fibrinolysis protein carbonylation was quantified. An SDS-PAGE was run to check the presence of cross-linking between fibrinogen chains. GA induced a delay in plasma coagulation and in fibrin polymerization. Maximum absorbance decreased after GA treatment, indicating the generation of thinner fibers. Fibrin generated after complete coagulation showed resistance to enzymatic digestion, which could be related to the generation of thinner fibers. Protein carbonylation also increased after GA treatment. All parameters could be reversed with AMG (a carbonyl trap) co-treatment. The data presented herein indicate that GA causes post-translational modification of lysine and arginine residues, which are central to many events involving fibrinogen to fibrin conversion, as well as to fibrinolysis. These modifications lead to the generation of persistent clots and may contribute to mortality seen in pathologies such diabetes and sepsis.
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PMID:Glycolaldehyde induces fibrinogen post-translational modification, delay in clotting and resistance to enzymatic digestion. 1939 1

The antioxidant activity of L-carnosine (beta-alanyl-L-histidine, bioactivated in ocular tissues) versus N-acetylcarnosine (N-acetyl-beta-alanyl-L-histidine, ocular-targeted small dipeptide molecules) was studied in aqueous solution and in a lipid environment, employing liposomes as a model of lipid membranes. Reactive oxygen species (ROS) were generated by an iron/ascorbate promoter system for induction of lipid peroxidation (LPO). L-carnosine, which is stabilized from enzymatic hydrolysis, operates as a universal aldehyde and ROS scavenger in both aqueous and lipid environments and is effective at preventing ROS-induced damage to biomolecules. Second-generation carnosine analogs bearing the histidyl-hydrazide moiety were synthesized and tested versus L-carnosine for their ability to reverse the glycation process, also known as the Maillard reaction, and reverse the stable intermolecular cross-links, monitored in the glucose-ethylamine Schiff base model, ultimately resulting in the formation of the advanced glycation end products (AGEs) from nonenzymatic glycation, accumulating in numerous body tissues and fluids. The obtained data demonstrate the transglycation properties of the ophthalmically stabilized L-carnosine and L-carnosine histidyl-hydrazide derivatives tested and can be used to decrease or predict the occurrence of long-term complications of AGE formation and improve therapeutically the quality of vision and length of life for diabetes mellitus patients and survivors with early aging. Scientists at Innovative Vision Products, Inc. (IVP), developed lubricant eyedrops designed as a sustained-release 1% N-acetylcarnosine prodrug of L-carnosine. The eyedrops contain a mucoadhesive cellulose-based compound combined with corneal absorption promoters and glycerine in a drug-delivery system. Anti-aging therapeutics with the ophthalmic drug eyedrop formula including N-acetylcarnosine showed efficacy in the nonsurgical treatment of age-related cataracts for enrolled participants in the prospective, randomized, double-masked, placebo-controlled crossover clinical trial after controlling for age, gender, and daily activities. In a cohort in excess of 50,500 various patients seeking cutting-edge medical care, the N-acetylcarnosine topical eyedrops target therapy was demonstrated to have significant efficacy, safety, and good tolerability for the prevention and treatment of visual impairment in this older population with relatively stable patterns of causes for blindness and visual impairment. Overall, accumulated study data demonstrate that the IVP-designed new vision-saving drugs, including N-acetylcarnosine eyedrops, promote health vision and prevent vision disability from senile cataracts, primary open-angle glaucoma, age-related macular degeneration, diabetic retinopathy, and aging. N-acetylcarnosine eyedrop therapy is the crown jewel of the anti-aging medical movement and revolutionizes early detection, treatment, and rejuvenation of aging-related eye-disabling disorders. N-acetylcarnosine, as an innovative medical science tool and component of the home medicine and alternative medicine approaches, has the potential to alleviate visual impairment and its associated social, economic, and political woes for an aging population.
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PMID:N-acetylcarnosine lubricant eyedrops possess all-in-one universal antioxidant protective effects of L-carnosine in aqueous and lipid membrane environments, aldehyde scavenging, and transglycation activities inherent to cataracts: a clinical study of the new vision-saving drug N-acetylcarnosine eyedrop therapy in a database population of over 50,500 patients. 1948 26

Mechanism of most of herbal used for diabetes mellitus treatment has not been well defined. This study was performed to investigate hypoglycemic effect of walnut leaf (Juglans regia L.), coriander leaf (Coriandrum sativum L.) or pomegranate seed (Punica granatum L.), and their possible role on pancreatic tissue. Diabetes mellitus was induced in 20 adult male Sprague Dawley rats and the animals were divided into four groups; three of them fed a diet supplemented with about 15 gram (60 g/ kg body weight /day) of mentioned plants for 15 days. The fourth diabetic untreated group (positive control) and a non-diabetic group (negative control) received standard diet. Blood glucose was measured every day and on the last day pancreases were isolated and stained with hematoxylin & eosin (H&E) and Gomeri aldehyde fuchsin (GAF). Histomorphology and following morphometric factors were studied; Volume density of beta cells, volume density of islets, percent of beta cells, number of islets per square centimeter and average area of islets. The results of this study indicate that only walnut leaf was able to reduce blood glucose significantly compared with diabetic untreated group (9.029 vs. 14.358 mmol/l) (P<0.05). Hypercellularity of islets tissue, increased hyperchromic nucleus in pancreatic islets of this group was obvious. Density of islets in pancreatic tissue, percent of beta cells and islets size increased significantly in this group in comparison with diabetic untreated group which may signify regeneration of islets or beta cells in group received walnut leaf (P<0.05).
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PMID:Effect of walnut leaf, coriander and pomegranate on blood glucose and histopathology of pancreas of alloxan induced diabetic rats. 2016 93

Abnormal proliferation of vascular smooth muscle cells (VSMC) is a key feature of development of cardiovascular complications, atherosclerosis, and restenosis. Patients with diabetes have higher risk for restenosis after coronary angioplasty than nondiabetic patients due to hyperglycemia-induced release of cytokines such as TNF-alpha. However, the molecular mechanisms regulating VSMC proliferation remain unclear. Herein, we report that inhibition of the polyol pathway enzyme aldose reductase (AR) prevents high glucose (HG)- and/or TNF-alpha-induced VSMC proliferation by accumulating cells at the G1 phase of the cell cycle. Treatment of VSMC with AR inhibitor sorbinil prevented HG- as well as TNF-alpha-induced phosphorylation of retinoblastoma protein and activation of E2F-1. Inhibition of AR also prevented HG- and TNF-alpha-induced phosphorylation of cyclin-dependent kinase (cdk)-2 and expression of G1/S transition regulatory proteins such as cyclin D1, cyclin E, cdk-4, c-myc, and proliferative cell nuclear antigen. More importantly, inhibition of AR prevented the increased expression of E2F-1 and proliferative cell nuclear antigen in diabetic rat aorta. Treatment of VSMC with the most abundant and toxic lipid aldehyde 4-hydroxy-trans-2-nonenal (HNE) or its glutathione conjugate [glutathionyl (GS)-HNE] or AR-catalyzed product of GS-HNE, GS-1,4-dihydroxynonane, resulted in increased E2F-1 expression. Inhibition of AR prevented HNE- or GS-HNE-induced but not GS-1,4-dihydroxynonane-induced up-regulation of E2F-1. Collectively, these results show that AR could regulate HG- and TNF-alpha-induced VSMC proliferation by altering the activation of G1/S-phase proteins such as E2F-1, cdks, and cyclins. Thus, inhibition of AR may be a useful therapeutic approach in preventing vascular complications.
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PMID:Aldose reductase regulates vascular smooth muscle cell proliferation by modulating G1/S phase transition of cell cycle. 2030 28

Aldose reductase is a member of aldehyde-keto reductase superfamily widely existing in the kidney, adrenal gland, lens, retina, nerve, heart, placenta, brain, skeletal muscle, testis, blood vessels, lung, liver, et al. It is a reduced nicotinamide-adenine dinucleotide phosphate (NADPH)-dependent enzyme catalyzing the reduction of various aldehydes and ketones to the corresponding alcohol. It is involved in many oxidative stress diseases, cell signal transduction and cell proliferation process as well as diabetes complications. In recent years, some progress has been made in research of the activity and gene regulation of aldose reductase and the relation with many common diseases.
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PMID:[Research progress in aldose reductase]. 2044 67


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