Level Of Fructosamine Research Articles

Correlation between Serum Fructosamine and Self- Monitoring Blood Glucose in Patients with Diet-Controlled Gestational Diabetes Mellitus

Objective: To determine the correlation between serum fructosamine and self-monitoring blood glucose (SMBG) levels in gestational diabetes mellitus (GDM) patients treated by dietary control and to identify the cutoff level of serum fructosamine for determining poorly controlled GDM. Materials and Methods: A cross-sectional study conducted between October 2021 and August 2022 at Queen Savang Vadhana Memorial Hospital that included 78 singleton pregnancies diagnosed with GDM assigned to diet therapy with lifestyle modification. The daily home SMBG was performed following the standard protocol and the serum fructosamine was measured one month after starting dietary control. The correlation between serum fructosamine and means of SMBG were analyzed. The receiver operating characteristics (ROC) curve was plotted to identify the cutoff level of serum fructosamine for predicting poorly controlled GDM based on SMBG levels. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the cutoff level were calculated. Results: The correlation between serum fructosamine and SMBG were 0.436 (p<0.001) and 0.618 (p<0.001) in pre-prandial and post-prandial glucose levels, respectively. The poorly controlled SMBG group had serum fructosamine greater than the well-controlled group with a mean of 165.7±35 and 132.8±23 μmol/L (p<0.001). The ROC curve showed that using 160 μmol/L as the optimal cutoff level to determine poorly controlled GDM had 72.7% sensitivity, 88% specificity, 50% PPV, 95.2% NPV, and 85.9% accuracy. Conclusion: The serum fructosamine was very useful for monitoring dietary control of GDM in terms of drawing blood less frequently, convenient, and more economical. An optimal cutoff point for screening a poorly controlled GDM was 160 mol/L. Keywords: Gestational diabetes mellitus; Serum fructosamine; Self-monitoring blood glucose

Antiglycation and antioxidant potential of coumaric acid isomers: a comparative in-vitro study

Advanced glycation end products (AGEs) are the product of non-enzymatic glycation of serum proteins. AGEs increase reactive oxygen species (ROS) formation, which leads to diabetic complications. Phytochemicals exhibit lesser side effects as compared to conventional therapy. In this study, three isomers of coumaric acid (ortho, meta, para) were used to deduce the better one in terms of reducing diabetic complications. For this purpose, human serum albumin (HSA) was incubated with glucose in the absence and presence of isomers for 28 days. To avoid any growth, NaN3 was added and temperature was kept constant throughout the incubation period. Studies like fluorescence, circular dichroism spectroscopy, fructosamine analysis, free lysine estimation, free thiol group estimation were done. To investigate the ROS production, fluorescence microscopy of isolated lymphocytes using DAPI and dichloro-dihydro-fluorescein diacetate were performed. Molecular docking and molecular dynamic simulations (root-mean-square deviation, root-mean-square fluctuations, radius of gyration and solvent-accessible surface area) of HSA and peroxisome proliferator activated receptor (PPAR) alpha and gamma were also done. It was observed that in glycated protein samples, the level of absorbance, fluorescence, fructosamine and carbonyl group increased along with the loss of secondary structure, free lysine and thiol group. These parameters were found gradually recovered in treated samples. ROS production and apoptosis were found to be reduced in lymphocytes treated with p-Coumaric acid (pCA)-treated protein samples as compared to lymphocyte treated with glycated protein. Computational modelling suggested a stable complex formation of HSA and PPARs with pCA. Results with pCA at 200 µM were consistently better than other two isomers. Our next step is to evaluate this study in rats. Communicated by Ramaswamy H. Sarma

The Importance of Fructosamine for Monitoring the Compensation and Effectiveness of Diabetes Treatment.

The use of fructosamine to assess the glycemic control represents a new step in diagnostics, and it has been accompanied by the active scientific discussion in recent years. That is why the purpose of this work is to study the average level of fructosamine in apparently healthy individuals and individuals with diabetes mellitus (DM), as well as the possibility to use it when evaluating the effectiveness of inpatient treatment of patients with hyperglycemia on the seven to ten days of hospitalization. This research work was carried out in Alma-Ata, Republic of Kazakhstan, based on the endocrinology department in the period from 2020 to 2022. The work consists of a retrospective analysis of previously examined patients and a prospective stage. The statistical evaluation was carried out with the calculation of reliability coefficient, confidence interval, and criteria for testing for normality. The level of fructosamine in healthy individuals in the corresponding region was analyzed in this article for the first time, and the correlation between this indicator and the level of glycated hemoglobin was found. The effectiveness of treatment of the Type 2 DM (according to the treatment protocol) has also been studied in stationary conditions for the seven to ten days, which makes it possible to judge the effectiveness of the prescribed therapy. These results will allow identifying the irrationality of the prescribed therapy at an early stage, which is especially important for the correct management of patients with this pathology, and minimizing the possible complications.

Association of Alternative Markers of Carbohydrate Metabolism (Fructosamine and 1,5-Anhydroglucitol) with Perioperative Characteristics and In-Hospital Complications of Coronary Artery Bypass Grafting in Patients with Type 2 Diabetes Mellitus, Prediabetes, and Normoglycemia.

In the cohort of 383 patients, besides the routine examination, additional markers of carbohydrate metabolism were determined before and on days 7-8 after CABG: glycated hemoglobin (HbA1c), fructosamine, and 1,5-anhydroglucitol. We evaluated the dynamics of these parameters in groups of patients with diabetes mellitus, prediabetes, and normoglycemia, as well as the association of these parameters with clinical parameters. Additionally, we assessed the incidence of postoperative complications and factors associated with their development. In all groups of patients (diabetes mellitus, prediabetes, normoglycemia), there was a significant decrease in the level of fructosamine on the 7th day after CABG compared with baseline (p1st-2nd point 0.030, 0.001, and 0.038 in groups 1, 2, and 3, respectively), whereas the level of 1,5-anhydroglucitol did not change significantly. The preoperative level of fructosamine was associated with the risk of surgery according to the EuroSCORE II scale (p = 0.002), as were the number of bypasses (p = 0.012), body mass index and overweightness (p < 0.001 in both cases), triglyceride (p < 0.001) and fibrinogen levels (p = 0.002), preoperative and postoperative glucose and HbA1c levels (p < 0.001 in all cases), left atrium size (p = 0.028), multiplicity of cardioplegia, cardiopulmonary bypass duration and aortic clamp time (p < 0.001 in all cases). The preoperative level of 1,5-anhydroglucitol showed an inverse correlation with fasting glucose and fructosamine levels before surgery (p < 0.001 in all cases), intima media thickness (p = 0.016), and a direct correlation with LV end-diastolic volume (p = 0.020). The combined endpoint (presence of significant perioperative complications + extended hospital stay after surgery >10 days) was identified in 291 patients. In binary logistic regression analysis patient age (p = 0.005) and fructosamine level (p = 0.022) were independently associated with the development of this composite endpoint (presence of significant perioperative complications + extended hospital stay after surgery >10 days). This study demonstrated that in patients after CABG there was the significant decrease in the level of fructosamine compared with baseline, whereas the level of 1,5-anhydroglucitol did not change. Preoperative fructosamine levels were one of the independent predictors of the combined endpoint. The prognostic value of preoperative assessment of alternative markers of carbohydrate metabolism in cardiac surgery deserves further study.

Identification of chronic stress biomarkers in dairy cows

Stress in dairy herds can occur from multiple sources. When stress becomes chronic because of a long duration and inability of animals to adapt, it is likely to deeply affect the emotional state, health, immunity, fertility and milk production of cows. While assessing chronic stress in herds would be beneficial, no real consensus has emerged from the literature regarding the indicators of interest. The goal of this study was to compare and evaluate potential biomarkers for chronic stress after inducing stress over a 4-week period through severe overstocking, restricted access to feed and isolated unusual events. A total of 30 cows were involved in the experiment and two similar groups were constituted. Over a 4-week period, the 15 cows of the stress group were housed in overstocked conditions, with 4.6 m2 per cow, including resting and feeding areas. In this area, only seven individual places at the feeding area were available for the 15 cows to generate competition for feed access. Twice during the trial and over a period of 2 h, an additional stress was induced by moving cows to an unfamiliar barn and diffusion of stressing noises (dog barking). Meanwhile, the 15 cows of the control group stayed in the original barn, with more than 10 m2 per cow and more individual places at the feeding area than cow number. On a weekly basis, several variables considered as potential biomarkers for chronic stress were recorded. Collected data were analysed using single trait linear repeated mixed models. No differences were observed regarding milk yield, BW of cows or body condition score but the milk loss was more pronounced in the stress group. The activity was more heterogeneous and the rumination of cows was lower in the stress group. The heart rate was lower in the stress group and showed more heterogeneity at the end of the stress period. No differences were observed regarding salivary cortisol, blood glucose, β-endorphin, thyroxine and leucocyte profile. A higher level of hair cortisol and blood fructosamine were observed in the stress group at the end of the stress period. Regarding the practical use of the highlighted biomarkers, milk loss may be an effective and easy way to detect general problems, including stress. The blood fructosamine and the hair cortisol concentrations are promising indicators to assess chronic stress in commercial farms.

Significance of fructosamine in the diagnosis of carbohydrate metabolism disorders in children with cystic fibrosis

Introduction. Cystic fibrosis associated (related) diabetes mellitus (CFDM) is one of the most common severe complications of cystic fibrosis. Today, the issue of the goodness of a single measurement of fasting blood glucose, glycated hemoglobin and fructosamine to assess the degree of carbohydrate metabolism disorders in children with cystic fibrosis is a subject of debate. The gold standard for diagnosing carbohydrate metabolism disorders (impaired fasting glycemia, various pre-diabetic conditions, diabetes mellitus) is the oral glucose tolerance test. Data about the diagnostic value of fructosamine for predicting CFDM aren’t dispositive. No credible studies of fructosamine in children with cystic fibrosis have been found in the Russian medical literature.Aim. To determine the diagnostic informative value of the blood fructosamine and other single-measured glycemic marker levels in the early diagnosis of carbohydrate metabolism disorders at the pre-diabetes stage in children with cystic fibrosis.Materials and methods. The results of laboratory tests and instrumental examinations of 87 children with cystic fibrosis aged 5–18 years were reviewed. A cross-sectional study of fructosamine, fasting blood sugar and glycated hemoglobin level (some patients underwent an oral glucose tolerance test), and liver fibroelastometry were also performed.Results and discussion. An increase in the fructosamine level was observed, which indicates a possible CFDM in children (p = 0.049): CFDM is highly likely, if the level of fructosamine is ≥255.5 µmol/l (reference ranges for children are 272–285 µmol/l; sensitivity = 57.1%, specificity = 85.2%). It has been found that children with cystic fibrosis and liver cirrhosis have increased fructosamine levels: cut-off = 253.0 µmol/l (Sn – 70.0%, Sp – 85.2%).Conclusion. The fructosamine level, a single determination of fasting blood glucose and glycated hemoglobin are not informative markers for the diagnosis of pre-diabetic conditions in cystic fibrosis in children. It is important to bear in mind that concomitant liver cirrhosis can affect the fructosamine levels. CFDM can be diagnosed at the lower fructosamine level, despite the generally accepted ranges.

Ginsenoside derivatives inhibit advanced glycation end-product formation and glucose–fructose mediated protein glycation in vitro via a specific structure–activity relationship

Ginseng (Panax ginseng and red ginseng) extract has been reported to inhibit the formation of advanced glycation end-products (AGEs); however, the potential inhibitory activity of its major constituents (ginsenosides) against AGE formation is still unknown. In the present study, we investigated the inhibitory effect of ginsenoside derivatives on AGE formation. Herein, we assessed the activity of 22 ginsenosides, most of which significantly inhibited fluorescent AGE formation. Notably, ginsenoside Rh2, ginsenoside Rh1, and compound K exhibited the most potent AGE inhibitory potential with IC50 values of 3.38, 8.42, and 10.85 µM, respectively. The structure– activity relationship revealed that the presence of sugar moieties, hydroxyl groups, and their linkages, and the stereostructure of the ginsenoside skeleton played an important role in the inhibition of AGE formation. Furthermore, the inhibitory activity of the most active ginsenoside Rh2 on fructose-glucose-mediated protein glycation and oxidation of bovine serum albumin (BSA) was explored. Rh2 (0.1–12.5 µM) inhibited the formation of fluorescent AGE and non-fluorescent AGE, as well as the level of fructosamine and prevented protein oxidation by decreasing protein carbonyl formation and protein thiol group modification. Rh2 also suppressed the formation of the β-cross amyloid structure of BSA. Ginsenosides might be promising new anti-glycation agents for the prevention of diabetic complications via inhibition of AGE formation and oxidation-dependent protein damage.

Anti-hyperglycemic and ameliorative effect of concentrated hot water-infusion of Phragmanthera incana leaves on type 2 diabetes and indices of complications in diabetic rats.

This study investigated the anti-hyperglycemic effects of concentrated hot water infusion of Phragmanthra incana leaves as well as its ameliorative effect on indices related to diabetic complications in a type 2 diabetes model of rats. Type 2 diabetes was induced by feeding 10% fructose solution ad libitum for two weeks followed by an intraperitoneal injection of streptozotocin (40mg/kg body weight (b.w.)). Concentrated plant infusion was administered orally at a dose of 150 and 300mg/kg b.w. to two type 2 diabetes rat groups. Diabetic rats without treatment served as a negative control while the group administered with metformin was served as a positive control. The intervention lasted for 4weeks when a single oral dose was given daily for 5days a week. Body weight and blood glucose were determined every week. An oral glucose tolerance test was performed in the last week of treatment. The rats were sacrificed after 4weeks of intervention, and the blood and organs were harvested for further analysis. Both dosages of the plant infusion significantly improved body weight, pancreatic β-cell function (HOMA-β), insulin secretion and reduced blood glucose, insulin resistance (HOMA-IR) with concomitant reduction in the elevated level of serum α-amylase activity, fructosamine, uric acid, urea, and liver function enzymes. The liver glycogen content was significantly improved while the activity of liver glucose-6-phosphatase was significantly reduced. The results demonstrate the anti-hyperglycemic ability of P. incana and its ability to delay the onset of diabetic complications which can be exploited for the anti-diabetic drug discovery.

Flavonoids from Polyalthia longifolia prevents advanced glycation end products formation and protein oxidation aligned with fructose-induced protein glycation

Advanced glycation end products (AGEs) are reactive chemical entities formed by non-enzymatic reaction between reducing sugars and amino group of proteins. Enhanced accumulation of AGEs and associated protein oxidation contribute to pathogenesis of diabetes-associated complications. Here, we evaluated the inhibitory activity of flavonoid compounds isolated from the leaves of Polyalthia longifolia on formation of AGEs and protein oxidation. Antiglycation activity was determined by measuring the formation of AGE fluorescence intensity, Nε-(carboxymethyl) lysine, and level of fructosamine. Protein oxidation was examined using levels of protein carbonyls and thiol group. Compounds significantly (p < 0.001) restricted the formation of fluorescent AGEs in fructose- BSA and methylglyoxal-BSA systems. Furthermore, there was a decrease in levels of fructosamine and protein carbonyls, and elevation in level of thiol group in fructose-BSA in presence of flavonoids. In summary, flavonoids from Polyalthia longifolia inhibit fructose-mediated protein glycation and oxidation, and can be potential agent for preventing AGE-mediated diabetic complications.

Analysis of the level of fructosamine in liver diseases

Objective To investigate the level of fructosamine in different liver diseases. Methods From October 2016 to October 2017, 153 patients with liver diseases hospitalized in Tongling Municipal Hospital were selected as study group, including 58 patients with chronic hepatitis B(CHB), 35 patients with liver cirrhosis(LC), 60 patients with primary hepatocellular carcinoma(HCC). Meanwhile, 40 healthy subjects were selected as control group.The total protein(TP), albumin (ALB), cystatin C(CysC), sialic acid(SA) and fasting blood glucose(FBG) were statistically analyzed. Results The difference of fructosamine between the HCC group and the LC group, the CHB group and the control group was statistically significant[(299.1±96.9)μmmol/L, (259.3±41.5)μmmol/L, (248.7±29.5)μmmol/L, (234.9±20.2)μmmol/L](F=11.321, P 0.05). Correlation analysis showed that there was a positive correlation between fructosamine and FBG in the CHB group(r=0.655, P 0.05). Logistic stepwise regression analysis showed that in the HCC group, fructosamine(OR=1.029, 95% CI: 1.007~1.052), CysC (OR=5 454.909, 95% CI: 78.117~380 916.873) and SA(OR=1.155, 95% CI: 1.047~1.275) were independent risk factors of HCC. Conclusion It has positive correlation between fructosamine and FBG in CHB and LC patients, fructosamine may not be related to glycometabolism in HCC patients, but the data of fructosamine reflect the degree of glycosylation of HCC tumor cells. Key words: Liver diseases; Hepatitis B; Liver cirrhosis; Liver neoplasms; Fructosamine; Glycosylation; Sialic acids

Glycated Peptide Levels Are Associated With Cognitive Decline Among Nondiabetic Older Women.

The association between diabetes and dementia may be explained in part by elevated levels of glycated peptides; we sought to determine whether serum-glycated peptides predicted cognitive decline in nondiabetic older adults. We prospectively studied 525 community-dwelling nondiabetic women, mean age of 82 years, and analyzed baseline glycated peptides (serum level of fructosamine and glycated albumin). Cognitive outcomes included 5-year decline on the short Mini-Mental State Examination (sMMSE), Trails B, and performance on a battery of five other cognitive tests at the follow-up visit. Generalized linear models were adjusted for education, age, race, physical activity, body mass index, and vascular disease. Women with higher level of fructosamine (upper two tertiles) had greater 5-year decline in Trails B performance compared with women in the lowest tertile (adjusted mean change = 67 vs 50 seconds, p = .046), but change in sMMSE was not different between groups. Higher fructosamine was also associated with worse cognitive function 5 years later: adjusted mean score for the California Verbal Learning Test-II Short Form was 22.7 versus 23.9 (p = .010) and for Category Fluency was 10.1 versus 11.1 (p = .003). Higher glycated albumin was also associated with worse performance on Category Fluency (10.1 vs 11.1, p = .003) but not on any other test. Among older nondiabetic women, higher concentrations of glycated peptides may be associated with greater cognitive decline, especially in measures of executive function. These associations may present new opportunities for targeted prevention and therapeutic strategies in cognitive aging.

Polyphenols of leaves of Apium graveolens inhibit in vitro protein glycation and protect RINm5F cells against methylglyoxal-induced cytotoxicity

Background: The health benefits of edible plants have been widely investigated and disseminated. However, only polyphenols have been found to have sufficient therapeutic potential to be considered in clinical trials. Fewer manuscripts have other applications such as prospective health benefits and disease treatment. Other components of edible plants are responsible for a range of other benefits including antimalarial, burns, flu, cancer, inflammation, diabetes, glycation, antimicrobial, prevention of neurodegeneration, analgesic, antimigraine activity, sedative activities, etc. Accordingly, the public needs to be informed of the potential edible plants have to act on different targets and maintain better control over diabetes compared to commercial drugs which can be toxic, have side effects, do not have the capacity to maintain blood glucose at normal levels, and do not protect the patient from the complications of diabetes over time. Consequently, edible plants, such as Apium graveolen, which have therapeutic targets on AGEs formation, are potentially a better alternative treatment for diabetes.Methods: The leaves of celery were extracted with methanol (CM). Polyphenols contents in CM were investigated by liquid chromatography-electrospray ionization mass. The ability of the compounds to inhibit formation of AGEs was evaluated in vitro models using formation of AGE fluorescence intensity, level of fructosamine, Nε-(carboxymethyl)lysine (CML), methylglyoxal (MG)-derived protein, and formation of amyloid cross β structure. Protein-oxidation was determined by thiol group and protein carbonyl content. Inhibition of MG-derived AGEs and MG-trapping ability were also measured. Additionally, insulin production was determined in methylglyoxal-treated pancreatic RINm5F cells assay. Results: Apigenin, kaempferol, apiin, rutin, caffeic acid, ferulic acid, chlorogenic acid, coumaroylquinic acid, and p-coumaric acid were the major polyphenols contained in CM. In all the model tests CM displayed potent AGE inhibitory activity, suggesting that CM delayed the three stages of glycation. Accordingly, the mechanisms of action of celery involving dicarbonyl trapping and breaking the crosslink structure in the AGEs formed may contribute to the protection of pancreatic RINm5F cells against MG conditions.Conclusion: These findings indicate that CM have an excellent anti-glycation effect which may be beneficial for future development of antiglycating agents for the treatment of diabetes.Keywords: Apium graveolens, anti-glycation, polyphenols methylglyoxal, insulin, pancreatic cells

Attenuation of Glucose-Induced Myoglobin Glycation and the Formation of Advanced Glycation End Products (AGEs) by (R)-α-Lipoic Acid In Vitro.

High-carbohydrate containing diets have become a precursor to glucose-mediated protein glycation which has been linked to an increase in diabetic and cardiovascular complications. The aim of the present study was to evaluate the protective effect of (R)-α-lipoic acid (ALA) against glucose-induced myoglobin glycation and the formation of advanced glycation end products (AGEs) in vitro. Methods: The effect of ALA on myoglobin glycation was determined via the formation of AGEs fluorescence intensity, iron released from the heme moiety of myoglobin and the level of fructosamine. The extent of glycation-induced myoglobin oxidation was measured via the levels of protein carbonyl and thiol. Results: The results showed that the co-incubation of ALA (1, 2 and 4 mM) with myoglobin (1 mg/mL) and glucose (1 M) significantly decreased the levels of fructosamine, which is directly associated with the decrease in the formation of AGEs. Furthermore, ALA significantly reduced the release of free iron from myoglobin which is attributed to the protection of myoglobin from glucose-induced glycation. The results also demonstrated a significant protective effect of ALA on myoglobin from oxidative damage, as seen from the decreased protein carbonyls and increased protein thiols. Conclusion: The anti-glycation properties of ALA suggest that ALA supplementation may be beneficial in the prevention of AGEs-mediated diabetic and cardiovascular complications.

(R)-\u03b1-Lipoic acid inhibits fructose-induced myoglobin fructation and the formation of advanced glycation end products (AGEs) in vitro

BackgroundFructose-mediated protein glycation (fructation) has been linked to an increase in diabetic and cardiovascular complications due to over consumption of high-fructose containing diets in recent times. The objective of the present study is to evaluate the protective effect of (R)-α-lipoic acid (ALA) against fructose-induced myoglobin fructation and the formation of advanced glycation end products (AGEs) in vitro.MethodsThe anti-glycation activity of ALA was determined using the formation of AGEs fluorescence intensity, iron released from the heme moiety of myoglobin and the level of fructosamine. The fructation-induced myoglobin oxidation was examined using the level of protein carbonyl content and thiol group estimation.ResultsThe results showed that co-incubation of myoglobin (1 mg/mL), fructose (1 M) and ALA (1, 2 and 4 mM) significantly inhibited the formation of AGEs during the 30 day study period. ALA markedly decreased the levels of fructosamine, which is directly associated with the reduction of AGEs formation. Furthermore, ALA significantly reduced free iron release from myoglobin which is attributed to the protection of myoglobin from fructose-induced glycation. The results also demonstrated a significant protective effect of ALA on myoglobin oxidative damages, as seen from decreased protein carbonyl content and increased protein thiols.ConclusionThese findings provide new insights into the anti-glycation properties of ALA and emphasize that ALA supplementation is beneficial in the prevention of AGEs-mediated diabetic and cardiovascular complications.

In Vitro Inhibitory Activity of Acca sellowiana Fruit Extract on End Products of Advanced Glycation.

IntroductionHyperglycemia plays an important role in the pathogenesis of diabetic complications, as it increases protein glycation, as well as the progressive accumulation of advanced glycation end products (AGEs), which are complex structures that produce fluorescence. The glycation reaction raises the levels of protein carbonyl, N ε-(carboxymethyl)lysine (CML), and fructosamine and decreases the level of thiol groups.MethodsIn the present study, the antiglycation activity was determined by fluorescence intensity using the bovine serum albumin (BSA)/glucose, CML method, and the level of fructosamine. The oxidation of proteins was determined by the carbonyl protein content and thiol groups.ResultsThe results show that the hexane extract of Acca sellowiana (FOH) at different concentrations (0.30–5 mg/ml) significantly inhibited the formation of AGEs in the BSA/glucose model during the 4 weeks of the study. FOH reduced the levels of fructosamine and CML. Our results showed a significant effect of FOH in the prevention of oxidative damage of proteins, as well as an effect on the oxidation of thiol groups and carbonyl proteins.ConclusionThe present study indicates that FOH is effective in inhibiting the glycation of proteins in vitro, so it can prevent or ameliorate the chronic conditions of diabetes associated with the formation of AGEs.

Дослідження впливу екстрактів з листя стевії та чорниці на показники розвитку експериментального цукрового діабету, індукованого високофруктозною дієтою з додаванням ін’єкцій дексаметазону

Introduction. Diabetes mellitus type 2 (DM 2) is a metabolic disease, which is characterized by chronic hyperglycemia. It develops as a result of insulin secretion disorder or mechanisms of its interaction with tissue cells. It is known that hyperglycemia is the main cause of cardiovascular complications development.The aim of the work – to study the effect of dry extracts from stevia and bilberry leaves on the metabolic disorders development in rats with experimental diabetes mellitus, caused by dexamethozone on a high-fructose diet ground.Methods of the research. The concentration of glycosylated hemoglobin, the level of fructosamine, the area under the glycemic curves, the level of immunoreactive insulin have been determined in the serum. Lipoperoxidation indicators have been determined according to diene conjugates (DC) and TBA-reactive products (TBA-RAP) content, the state of the antioxidant system has been assessed by reduced glutathione concentration determining (GSH) [8]. The significance of intergroup differences have been assessed due to Student's t-criterion.Results and discussion The introduction of low-dose dexamethasone in laboratory animals causes a complex of disorders, which are specific for metabolic syndrome and type 2 diabetes. Thus, a rise in the level of glycosylated hemoglobin, a concentration of fructosamine, a glucose level, a basal glycemia level, an increase in the area under the glycemic curves are observed in the serum of rats under the indicated conditions. With the introduction of dry extracts of stevia and bilberry leaves together with dexamethasone, the normalizing influence of these substances on the investigated indicators is observed.Conclusions. The use of dry extracts from stevia and bilberry leaves has a normalizing effect on glycosylation indicators, glucose level and lipid metabolism in the rats’ serum in type 2 diabetes mellitus. The more pronounced antioxidant effect of the extract from bilberry leaves and the hypoglycemic action of the extract from stevia leaves have been shown. This proves the advisability of the extracts from stevia and bilberry leaves joint application with the aim of drugs creation on their basis for metabolic disorders correction.

Serum fructosamine, serum glycated albumin and serum glycated β-lipoprotein in type 2 diabetes mellitus patients with and without microvascular complications.

BackgroundGlycation of serum proteins has been proposed as an important mechanism of complications of diabetes but whether there are differences in glycation of different serum proteins and whether it has any correlation with development of microvascular complications has not been studied in depth. This study aimed to assess level of serum fructosamine, glycated albumin and glycated β-lipoprotein in type 2 diabetes mellitus patients with and without microvascular complications and to find out their correlation with diabetes complications.MethodsCase–control study involving 150 individuals at a tertiary care hospital in western India. Fifty participants were healthy controls (group 1), 50 were type 2 diabetes patients without any evident microvascular complication (group 2) and 50 were type 2 diabetes patients with one or more microvascular complications (group 3). Serum fructosamine, FBS, PP2BS and other biochemical parameters were measured. Glycated albumin and glycated β-lipoprotein were measured by agarose gel electrophoresis followed by NBT staining. Unpaired t-test was used to find out significance of difference between two groups and correlation coefficient to find out statistical correlation between two variables.ResultsType 2 diabetes patients with one or more microvascular complications had poor glycemic control as indicated by markers of short and mid-term glycemia. Differences between the groups for fructosamine, glycated albumin and glycated β-lipoprotein were significant (p < 0.001). Glycated albumin correlated with FBS, PP2BS and fructosamine in all diabetic patients (group 2 and 3) whereas glycated β-lipoprotein correlated with these parameters only in group 3 and it was markedly elevated in group 3.ConclusionSerum glycated β-lipoprotein was disproportionately elevated compared to fructosamine and glycated albumin in diabetes patients with microvascular complications (group 3) and it correlated with rest of glycemic markers only in this group. Glycated β-lipoprotein might help in identifying diabetic individuals at high future risk of developing microvascular complications.

Moringa oleifera aqueous leaf extract inhibits reducing monosaccharide-induced protein glycation and oxidation of bovine serum albumin.

Advanced glycation end products (AGEs) play an important factor for pathophysiology of diabetes and its complications. Moringa oleifera is one of the medicinal plants that have anti-hyperglycemic activity. However, anti-glycation property of Moringa oleifera leaf extract on the different types of reducing monosaccharides-induced protein glycation has not been investigated. Therefore, the aim of this study was to examine the protective effect of Moringa oleifera aqueous leaf extract (MOE) on reducing sugars-induced protein glycation and protein oxidation. Total phenolic content of MOE was measured using the Folin–Ciocalteu method. Bovine serum albumin was incubated with 0.5 M of reducing sugars (glucose or fructose) with or without MOE (0.5–2.0 mg/mL) for 1, 2, 3 and 4 weeks. The results found that total phenolic content was 38.56 ± 1.50 mg gallic acid equivalents/g dry extract. The formation of fluorescent and non-fluorescent AGEs [Nε-(carboxymethyl) lysine (CML)] and the level of fructosamine were determined to indicate protein glycation, whereas the level of protein carbonyl content and thiol group were examined for protein oxidation. MOE (0.5–2.0 mg/mL) significantly inhibited the formation of fluorescent, Nε-CML and markedly decreased fructosamine level (P < 0.05). Moreover, MOE significantly prevented protein oxidation manifested by reducing protein carbonyl and the depletion of protein thiol in a dose-dependent manner (P < 0.05). Thus, the findings indicated that polyphenols containing in MOE have high potential for decreasing protein glycation and protein oxidation that may delay or prevent AGE-related diabetic complications.

Inhibitory effect of Clitoria ternatea flower petal extract on fructose-induced protein glycation and oxidation-dependent damages to albumin in vitro.

BackgroundThe accumulation of advanced glycation end products (AGEs) in body tissue has been implicated in the progression of age-related diseases. Inhibition of AGE formation is the imperative approach for alleviating diabetic complications. Clitoria ternatea extract (CTE) has been demonstrated to possess anti-diabetic activity. However, there is no scientific evidence supporting its anti-glycation activity. The objective of this study was to determine the inhibitory effect of CTE on fructose-induced formation of AGEs and protein oxidation. Antioxidant activity of CTE was also assessed by various methods.MethodsThe aqueous extract of CTE (0.25-1.00 mg/ml) was measured for the content of total phenolic compounds, flavonoid, and anthocyanin by Folin-Ciocalteu assay, AlCl3 colorimetric method, and pH differential method, respectively. The various concentrations of CTE were incubated with BSA and fructose at 37°C for 28 days. The formation of fluorescent AGEs, the level of fructosamine, protein carbonyl content, and thiol group were measured. The in vitro antioxidant activity was measured by the 1,1-diphenyl 2-picrylhydrazyl (DPPH) scavenging activity, trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), hydroxyl radical scavenging activity (HRSA), superoxide radical scavenging activity (SRSA), and ferrous ion chelating power (FICP).ResultsThe results demonstrated that the content of total phenolics, flavonoids and total anthocyanins in CTE was 53 ± 0.34 mg gallic acid equivalents/g dried extract, 11.2 ± 0.33 mg catechin equivalents/g dried extract, and 1.46 ± 0.04 mg cyanidin-3-glucoside equivalents/g dried extract, respectively. Moreover, CTE (0.25-1.00 mg/ml) significantly inhibited the formation of AGEs in a concentration-dependent manner. CTE also markedly reduced the levels of fructosamine and the oxidation of protein by decreasing protein carbonyl content and preventing free thiol depletion. In the DPPH radical scavenging activity and SRSA, CTE had the IC50 values of 0.47 ± 0.01 mg/ml and 0.58 ± 0.04 mg/ml. Furthermore, the FRAP and TEAC values of CTE were 0.38 ± 0.01 mmol FeSO4 equivalents/mg dried extract and 0.17 ± 0.01 mg trolox equivalents/mg dried extract. However, CTE showed weak scavenging activity on hydroxyl radical and a weak antioxidant iron chelator.ConclusionsThe results showed that CTE has strong antiglycation and antioxidant properties and might have therapeutic potentials in the prevention of AGE-mediated diabetic complications.

Protective effects of cyanidin-3-rutinoside against monosaccharides-induced protein glycation and oxidation

Cyanidin-3-rutinoside (C3R), a naturally occurring anthocyanin, is present in various fruits and vegetables as a colorant. C3R has been well characterized and demonstrated a number of biological activities attributed to its antioxidant properties. The present study compared the effectiveness of C3R against monosaccharide-induced protein glycation and oxidation in vitro using bovine serum albumin (BSA).The results demonstrated that C3R (0.125–1.00mM) inhibited the formation of fluorescent AGEs in ribose-glycated BSA (2–52%), fructose-glycated BSA (81–93%), glucose-glycated BSA (30–74%) and galactose-glycated BSA (6-79%).Correspondingly, C3R (1.00mM) decreased the level of Nɛ-(carboxymethyl) lysine (56-86%) in monosaccharide-induced glycation in BSA. C3R also reduced the level of fructosamine, β-amyloid cross structure, protein carbonyl content as well as the depletion of thiol in BSA/monosaccharide system. In summary, C3R might offer a new promising antiglycation agent for the prevention of diabetic complications by inhibiting AGE formation and oxidation-dependent protein damage.