Effect of levosimendan, an inodilator, on streptozotocin-induced diabetic nephropathy in rats

Type 2 diabetes mellitus in obesity promotes prolongation of cardiomyocyte contractile function, impaired Ca2+ handling and protein carbonylation damage

AIMS

To investigate whether the obesity associated to T2DM presented cardiomyocyte myocardial contractility dysfunction due to damage in Ca²⁺ handling, concomitantly with increased biomarkers of oxidative stress.

METHODS

Male Wistar rats were randomized into two groups: control (C): fed with standard diet; and obese (Ob) that fed a saturated high-fat. After the characterization of obesity (12 weeks), the Ob animals were submitted to T2DM induction with a single dose of intraperitoneal (i.p.) injection of streptozotocin (30 mg/kg). Thus, remained Ob rats that were characterized as to the presence (T2DMOb; n = 8) and/or absence (Ob; n = 10) of T2DM. Cardiac remodeling was measured by post-mortem morphological, isolated cardiomyocyte contractile function, as well as by intracellular Ca²⁺-handling analysis.

RESULTS

T2DMOb presented a significant reduction of all fat pads, total body fat and adiposity index. T2DMOb group presented a significant increase in protein carbonylation and superoxide dismutase (SOD) activity, respectively. T2DMOb promoted elevations in fractional shortening (15.6 %) and time to 50 % shortening (5.8 %), respectively. Time to 50 % Ca²⁺ decay was prolonged in T2DMOb, suggesting a possible impairment in Ca²⁺recapture and/or removal.

CONCLUSION

Type 2 diabetes mellitus in obesity promotes prolongation of cardiomyocyte contractile function with protein carbonylation damage and impaired Ca²⁺ handling.

Evaluation of vaspin and irisin hormones levels in diabetic rats and relationship with diet

BACKGROUND: Type-2 diabetes with an increasing prevalence is a public health problem. Irisin and vaspin, which are secreted a majority from adipose tissue, are discovered hormones recently, and their effects on diabetes are studied. OBJECTIVE: This study aims to the effects of diet on these hormones levels in diabetic rats. METHODS: In this study, ten-week-old 18 Wistar-Albino rats were divided into three groups randomly. The diabetic group (n = 6) was fed a high-fat diet (HFD). Other rats were divided into two control groups, one of them (n = 6) was fed a control diet (CD), and the other group (n = 6) was fed HFD. The feeding time for all groups was 4 weeks. Streptozotocin (STZ) was used for diabetes induction in rats. RESULTS: At the end of the four weeks, the body weight of the diabetic group decreased significantly. In the diabetic group compared to the control groups, it was observed that besides high fasting blood glucose (FBG), triglyceride, total cholesterol levels, and insulin resistance (HOMA-IR) scores. Vaspin levels were significantly higher in diabetic rats, while irisin levels were similar between groups. Besides, vaspin level correlation with biochemical parameters such as glucose, triglycerides, total cholesterol, and HOMA-IR score was significant. CONCLUSION: In conclusion, this study showed that besides the evidence that vaspine is a hormone associated with diabetes, diet composition could give an opinion about the type-2 diabetes process by looking at hormone levels.

Nephroprotective Effect of the Virgin Olive Oil Polyphenol Hydroxytyrosol in Type 1-like Experimental Diabetes Mellitus: Relationships with Its Antioxidant Effect

The aim of this study was to determine whether hydroxytyrosol administration prevented kidney damage in an experimental model of type 1 diabetes mellitus in rats. Hydroxytyrosol was administered to streptozotocin-diabetic rats: 1 and 5 mg/kg/day p.o. for two months. After hydroxytyrosol administration, proteinuria was significantly reduced (67-73%), calculated creatinine clearance was significantly increased (26-38%), and the glomerular volume and glomerulosclerosis index were decreased (20-30%). Hydroxytyrosol reduced oxidative and nitrosative stress variables and thromboxane metabolite production. Statistical correlations were found between biochemical and kidney function variables. Oral administration of 1 and 5 mg/kg/day of hydroxytyrosol produced an antioxidant and nephroprotective effect in an experimental model of type 1-like diabetes mellitus. The nephroprotective effect was significantly associated with the systemic and renal antioxidant action of hydroxytyrosol, which also influenced eicosanoid production.

Effect of flaxseed on systemic inflammation and oxidative stress in diabetic rats with or without chronic kidney disease

Background

Diabetes mellitus (DM) and chronic kidney disease (CKD) are common causes of morbidity and mortality. Flaxseed contains several bioactive compounds that have been shown to possess anti-inflammatory and antioxidative properties. The aim of the present study was to investigate the possible effect of flaxseed in diabetic rats with adenine–induced CKD.

Methods

Male Wister rats (n = 48) were randomly divided into seven equal groups and treated for 33 consecutive days as follows: G1: control. G2 adenine, G3: streptozotocin (STZ), G4: flaxseed, G5: adenine+flaxseed, G6: STZ+flaxseed, G7: adenine+STZ+flaxseed). DM or CKD were experimentally induced by a single intraperitoneal injection of streptozotocin (STZ) or by adenine via oral gavage, respectively.

Results

Rats fed adenine alone exhibited several changes including decreased body weight, increased food and water intake and urine output, increased urinary albumin/creatinine ratio. They also showed an increase in plasma urea and, creatinine, indoxyl sulfate, neutrophil gelatinase-associated lipocalin and cystatin C, and a decrease in renalase activity. These were associated with significant changes in inflammatory and oxidative biomarkers, e.g., increase in 8-isoprostane, 8 -hydroxy -2-deoxy guanosine and decrease in antioxidant enzymes, as well as increase in interleukins 1β and 6, and NF-κB, and a decrease in interlukin-10. Histopathologically, there was increased tubular necrosis and fibrosis. Concomitant administration of adenine and STZ further worsened the renal damage induced by adenine alone. Flaxseed significantly ameliorated the changes caused by adenine and STZ, given either singly or in combination.

Conclusion

These findings suggest that flaxseed is a potential therapeutic agent in attenuating the progression of CKD in diabetes.

Effect of levosimendan on renal function in background of left ventricular dysfunction: a meta-analysis of randomized trials

OBJECTIVE

Levosimendan, an inotrope, is widely used in the management of heart failure (HF) and cardiac surgery, but it remains uncertain whether levosimendan can improve renal function in patients with left ventricular dysfunction (LVD).

METHODS

PubMed, Embase, and Cochrane CENTRAL from the inception to June 2020 were systematically screened for randomized controlled trials (RCTs) to investigate whether levosimendan offers kidney-related advantages in cardiovascular patients with LVD. We pooled the effects using a random-effect model.

RESULTS

Twenty-eight studies enrolling 5069 patients were included. Levosimendan reduced the sCr (SMD -0.28, 95% CI (-0.48, -0.09), P = 0.005, I² = 52.5%, high quality) and the risk of ARF (relative risk 0.75, 95%CI (0.60, 0.95), P = 0.017, I² = 11.3%, moderate-quality) in patients with LVD compared with control group. The reduction of sCr was more pronounced in patients with a relatively higher baseline sCr level. For secondary outcomes, levosimendan therapy was associated with the improvement of GFR (SMD 0.32, 95%CI (-0.05, 0.68), P = 0.092, I² = 55.1%, low-quality) and urine output (SMD 0.42, 95%CI (0.06, 0.79), P = 0.024, I² = 50.0%, very low-quality), but there was no significant reduction in BUN (SMD -0.14, 95%CI (-0.97, 0.70), P = 0.774, I² = 77.9%, very low-quality).

CONCLUSIONS

Levosimendan might improve renal function of patients with LVD.