Antioxidant Enzymes and Lipid Peroxidation in Type 2 Diabetes Mellitus Patients with and without Nephropathy

BACKGROUND

Oxidative stress has been considered to be a pathogenic factor of diabetic complications including nephropathy. There are many controversies and limited studies regarding the antioxidant enzymes in diabetic nephropathy.

AIM

This study was to evaluate the levels of antioxidant enzymes and lipid peroxidation in Type-2 Diabetes Mellitus (DM) patients with and without nephropathy.

MATERIALS AND METHODS

The study included 90 age and sex matched subjects. Blood samples of all subjects were analyzed for all biochemical and oxidative stress parameters.

RESULTS

The malondialdehyde (MDA) levels and catalase (CAT) activity were significantly increased and reduced glutathione (GSH) levels and activities of glutathione peroxidase (GPx) and glutathione reductase (GR) were significantly decreased in Type-2 DM with and without nephropathy as compared to controls and also in Type-2 DM with nephropathy as compared to Type-2 DM without nephropathy. There were an excellent positive correlation of glycohemoglobin (HbA1c) with MDA and a good negative correlation of GPx with GSH in controls. There were positive correlations of GR, CAT, and superoxide dismutase (SOD) with MDA in Type-2 diabetes patients with nephropathy.

CONCLUSIONS

Intensity of oxidative stress in Type-2 diabetic patients with nephropathy is greater when compared with Type-2 diabetic patients without nephropathy as compared to the controls.

Association of contrast sensitivity with LogMAR visual acuity and glycosylated hemoglobin in non-insulin dependent diabetes mellitus

A tertiary care center-based prospective case-control study was undertaken to evaluate the association of contrast sensitivity with LogMAR visual acuity and glycosylated hemoglobin (HbA1c) in 205 cases of non-insulin dependent diabetes mellitus and 115 controls. LogMAR visual acuity and contrast sensitivity were scored using ETDRS and Pelli-Robson charts, respectively. Bivariate correlation between contrast sensitivity and LogMAR visual acuity showed significant inverse correlation in cases without retinopathy (r = -0.466) and with non-proliferative retinopathy (r = -0.307). In a multivariate model, on applying linear regression analysis, LogMAR visual acuity (p < 0.001) and HbA1c (p = 0.002) had significant association with contrast sensitivity. Significant difference in contrast sensitivity was not observed between cases without diabetic retinopathy and with non-proliferative diabetic retinopathy, implying no association with retinal microvascular changes. Contrast sensitivity dysfunction observed in diabetes mellitus results from changes in retinal function secondary to alteration in carbohydrate metabolism depicted in glycosylated hemoglobin.

Deuterohemin-AlaHisLys mitigates the symptoms of rats with non-insulin dependent diabetes mellitus by scavenging reactive oxygen species and activating the PI3-K/AKT signal transduction pathway

Damage to pancreatic β-cells plays an important role in the development of type 2 diabetes, and oxidative stress is a likely contributor. In the present study, we investigated the effect of deuterohemin-AlaHisLys (DhHP-3), a microperoxidase-11 mimic, on rats with non-insulin dependent diabetes mellitus and examined the action mechanisms of DhHP-3. The induced hyperglycemia, glucose intolerance, and insulin resistance in diabetic rats were associated with increased oxidative stress and damage to pancreatic islets. DhHP-3 (3 mg/kg) ameliorated hyperglycemia and insulin resistance, protected pancreas islet, decreased the content of malondialdehyde, and increased the activity of superoxide dismutase in plasma and pancreatic tissue by reducing ROS levels. Furthermore, DhHP-3 stimulated the proliferation of INS-1 cells and inhibited apoptosis by activating the phosphatidylinositol 3-kinase/protein kinase B (PI3-K/AKT) signaling pathway. Our results demonstrated for the first time that DhHP-3 decreased blood glucose level in rats with non-insulin dependent diabetes mellitus, scavenged reactive oxygen species, activated the PI3-K/AKT signaling pathway, and protected pancreatic β-cells against apoptosis.

A randomized placebo-controlled trial of the effect of coffee consumption on insulin sensitivity: Design and baseline characteristics of the Coffee for METabolic Health (COMETH) study

BACKGROUND

Coffee consumption has been consistently associated with a lower risk of type 2 diabetes mellitus in cohort studies. In addition, coffee components increased insulin sensitivity in animal models. However, data from intervention studies on the effect of coffee consumption on glucose metabolism have been limited by small sample sizes, lack of blinding, short follow-up duration and the use of surrogate indices of insulin sensitivity. We designed the Coffee for Metabolic Health (COMETH) study to evaluate the effect of coffee consumption on insulin sensitivity.

METHODOLOGY

The COMETH study is a double-blind randomized placebo-controlled 24-week trial. Participants were overweight, male and female habitual coffee consumers who were of Chinese, Malay and Asian-Indian ethnicity. We excluded smokers, persons with diabetes, and persons with low insulin resistance (HOMA-IR < 1.30). Participants were randomly assigned to receive daily 4 cups of instant regular coffee or 4 cups of a coffee-like placebo beverage. The hyperinsulinemic euglycemic clamp was performed at baseline and at the end of 24 weeks to determine changes in the bodyweight standardized M-value. Secondary outcomes included changes in fasting glucose and insulin sensitivity mediators such as adiponectin, markers of inflammation, liver function, and oxidative stress.We enrolled 128 participants, 126 (57.1% males; aged 35-67 years) of whom completed baseline assessments.

DISCUSSION

If improvement in insulin sensitivity in the coffee group is significantly greater than that of the placebo group, this would support the hypothesis that coffee consumption reduced risk of type 2 diabetes through biological pathways involving insulin sensitivity.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01738399. Registered on 28 November 2012. Trial Sponsor: Nestlé Research Center, Lausanne, Switzerland. Trial Site: National University of Singapore.

Severe hypoglycemia and risk of hospitalization for heart failure in adults with diabetes treated with oral medications with or without insulin: A population-based study

AIMS

We aimed to determine if severe hypoglycemia (SH) independently increases the risk of hospitalization for heart failure (hHF) in type 2 diabetes, regardless of the prevalent or incident cardiovascular disease (CVD).

METHODS

This was a nationwide population-based propensity score-matched study using Korean National Health Insurance Service data (2002-2018). The hazards of hHF were compared in individuals who experienced SH (n = 8,965) and 1:3 matched controls, among adults with diabetes using oral anti-diabetes medications (OADs) with or without insulin and without previous hHF at baseline.

RESULTS

During 236,417 person-years, 1,189 cases of hHF occurred. The hazard of hHF was higher in individuals with SH compared to matched controls (adjusted hazard ratio [aHR] 1.503, 95 % confidence interval [CI] 1.324-1.707). The increase in aHR remained significant when excluding participants with prevalent or incident major adverse cardiovascular events (MACE; aHR 1.352, 95 % CI 1.228-1.622) and any CVD (aHR 1.342, 95 % CI 1.025-1.756). Two or more SH events were associated with further increase in hHF risk.

CONCLUSION

SH was associated with increased risks of hHF among adults with diabetes using OAD with or without insulin. The increased risk was attenuated but remained significant in those without prevalent or incident MACE or CVDs.

Influence of consuming coffee and other beverages in adolescence on risk of type 2 diabetes in adulthood

BACKGROUND

Dietary strategies for type 2 diabetes (T2DM) prevention have mainly focused on solid foods and nutrients. Emanating evidence suggests that beverage consumption in adulthood may also influence T2DM development, whereas the role of beverages during adolescence remains unknow.

OBJECTIVE

To examine adolescent beverages consumption, and their changes from adolescence to adulthood in relation to T2DM risk in adulthood.

METHODS

This prospective cohort study, conducted within the Nurses' Health Study II (NHS II), enrolled 41,317 women who completed a food-frequency questionnaire (FFQ) regarding their diet in high school and had no diabetes, cardiovascular disease, or cancer at baseline (1997). Beverage consumption including coffee, tea, regular or diet soda, fruit juice or milk, was assessed using the FFQ. Cox proportional hazards models were utilized to estimate hazard ratios (HRs) for the association between beverage consumption in adolescence and risk of incident type 2 diabetes (T2DM) in adulthood, adjusting for potential confounders.

RESULTS

During 725,650 person-years of follow-up, 2,844 participants developed T2DM. After adjustment for demographic, lifestyle and dietary risk factors, comparing ≥ 1 serving/day with non-consumers, adolescent coffee [HR, 0.86 (95% confidence interval: 0.75 to 0.98); P-trend = 0.02)] and orange juice [HR, 0.83 (0.71 to 0.96); P-trend = 0.0008)] consumption was associated with lower T2DM risk, whereas, regular soda [HR, 1.37 (1.20 to 1.57); P-trend < 0.0001)] and iced tea [HR, 1.41 (1.21 to 1.65); P-trend < 0.0001)] intake was associated with higher T2DM risk. Increased coffee intake from adolescence to adulthood in 1991 was associated with a lower T2DM risk [HR, 0.70 (0.61 to 0.80); P-trend < 0.0001), comparing ≥ + 3 servings/day with no change], whereas the opposite was observed for increased regular soda [HR, 1.20 (1.06 to 1.35); P-trend = 0.004), comparing ≥ + 1 or more servings/week with no change)] and diet soda consumption [HR, 1.59 (1.41 to 1.80); P-trend = 0.0002), comparing ≥ + 2 servings/day with no change].

CONCLUSION

Adolescent consumption of coffee or orange juice intake was associated with a lower risk of T2DM, whereas the opposite was observed for intake of regular soda or iced tea. In addition, increased coffee intake was associated with a lower diabetes risk, whereas the opposite was observed for regular or diet soda intake. These data highlight a potentially important role of beverage intake at early life in the etiology of diabetes during adulthood.

Prognostic value of high sensitivity C-reaction protein in non-insulin dependent diabetes mellitus patients with non-alcoholic fatty liver disease

BACKGROUND AND PURPOSE

High sensitivity C-reaction protein (hsCRP) has been used as a significant predictive factor of cardiovascular events in patients with non-insulin dependent diabetes mellitus (NIDDM). However, existing reports in regards to the significance of hsCRP in predicting the progression of hepatic complications in NIDDM patients are too sparse to deliver clear results. This study is aimed at investigating the prognostic value of hsCRP in NIDDM patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

1128 NIDDM patients with a definite diagnosis of NAFLD were enrolled and followed for one year. The baseline body mass index (BMI), waist-hip circumference ratio (WHR), serum aspartate aminotransferase (AST), presence of hypertension, alanine aminotransferase (ALT), serum hsCRP, total cholesterol (Tch), fasting blood glucose (FBG), triglycerine (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and hepatitis B surface antigen (HBsAg) were recorded to analyze the significance of hsCRP in predicting the short-term progression from NAFLD to non-alcoholic steatohepatitis (NASH).

RESULTS

One year after baseline, 32% of the NAFLD patients suffered progression to NASH and the percentages of NASH were respectively 8.2%, 12.5%, 33.8% and 72.6% in 4 groups with quartered baseline serum level of hsCRP; there was significant difference among the 4 groups in percentage of NASH (P<0.001). With sex, age, WHR, BMI, hypertension, TG, TCH, HDL-C, LDL-C, FBG and HBsAg included, the calibrated regression model gave the OR values of 1.000, 1.669, 6.635 and 32.131 in in 4 quartered baseline serum levels of hsCRP.

CONCLUSION

High serum level of hsCRP is an independent risk factor of short-term progression to NASH in patients with NIDDM and NAFLD. Those NIDDM patients with NAFLD that present with high serum level of hsCRP should be subjected to regular monitoring, lifestyle intervention and medication.

Efficacy and safety of enavogliflozin vs. dapagliflozin as add-on therapy in patients with type 2 diabetes mellitus based on renal function: a pooled analysis of two randomized controlled trials

BACKGROUND

We assessed the efficacy and safety of enavogliflozin (0.3 mg), a newly developed SGLT-2 inhibitor, in patients with type 2 diabetes mellitus based on kidney function via pooled analysis of two 24-week, randomized, double-blind phase III trials.

METHODS

Data from 470 patients were included (enavogliflozin: 0.3 mg/day, n = 235; dapagliflozin: 10 mg/day, n = 235). The subjects were classified by mildly reduced (60 ≤ eGFR < 90 mL/min/1.73 m², n = 247) or normal eGFR (≥ 90 mL/min/1.73 m², n = 223).

RESULTS

In the mildly reduced eGFR group, enavogliflozin significantly reduced the adjusted mean change of HbA1c and fasting plasma glucose levels at week 24 compared to dapagliflozin (- 0.94% vs. -0.77%, P = 0.0196). Enavogliflozin exhibited a more pronounced glucose-lowering effect by HbA1c when combined with dipeptidyl peptidase-4 inhibitors than that observed in their absence. Enavogliflozin showed potent blood glucose-lowering effects regardless of renal function. Conversely, dapagliflozin showed a significant decrease in the glucose-lowering efficacy as the renal function decreased. Enavogliflozin showed a higher urinary glucose excretion rate in both groups. The homeostatic model assessment showed that enavogliflozin markedly decreased the insulin resistance. The blood pressure, weight loss, or homeostasis model assessment of beta-cell function values did not differ significantly between enavogliflozin and dapagliflozin. Adverse events were similar between both drugs.

CONCLUSIONS

The glucose-lowering efficacy of enavogliflozin is superior to that of dapagliflozin in patients with type 2 diabetes mellitus with mild renal function impairment; this is attributed to its potent urinary glucose excretion-promoting ability. The emergence of new and potent SGLT-2 inhibitors is considered an attractive option for patients with inadequate glycemic control and decreased renal function.

TRIAL REGISTRATION

Not applicable (pooled analysis).