Antioxidant effects of maslinic acid in livers, hearts and kidneys of streptozotocin-induced diabetic rats: Effects on kidney function
Renal Failure (Impact Factor: 0.94). 12/2013; 36(3). DOI: 10.3109/0886022X.2013.867799
Abstract Studies indicate that hyperglycemia-induced oxidative stress triggers the development of microvascular and macrovascular complications in diabetes. Accordingly, we hypothesized that maslinic acid (MA) prevents these complications due to its antioxidant properties. We, therefore, investigated the effects of 5-week MA treatment of streptozotocin (STZ)-induced diabetic rats on anti-oxidative status of cardiac, hepatic and renal tissues as well as on kidney function. Proximal tubular effects of MA were studied in anesthetized rats challenged with hypotonic saline after a 3.5 h equilibration for 4 h of 1 h control, 1.5 h treatment and 1.5 h recovery periods using lithium clearance. MA was added to the infusate during the treatment period. Oral glucose tolerance responses to MA were monitored in rats given a glucose load after an 18 h fast. Compared with untreated diabetic rats, MA-treated diabetic animals exhibited significantly low malondialdehyde (MDA, a marker of lipid peroxidation) and increased the activity of antioxidant enzymes; superoxide dismutase and glutathione peroxidase in hepatic, cardiac and renal tissues. The expressions of gastrocnemius muscle GLUT4 and kidney GLUT1 and GLUT2 were assessed to elucidate the mechanism of the hypoglycemic effects of MA. MA-treatment diminished the expression of GLUT1 and GLUT2 in diabetic kidney and reduced glycemia values of diabetic rats. MA administration increased urinary Na(+) outputs and additionally the FENa indicating that at least part of the overall reduction in Na(+) reabsorption occurred in the proximal tubules. These results suggest antioxidant effects of MA can ameliorate oxidative stress and improve kidney function in diabetes mellitus.
- [Show abstract] [Hide abstract]
ABSTRACT: Protective effects of maslinic acid (MA) at 10, 15 or 20 mg/kg body weight/day against alcohol-induced acute hepatotoxicity in mice were examined. Mice were administrated by MA for 3 weeks, and followed by alcohol treatment. Results showed that MA pre-intake at three doses resulted in its accumulation in liver; and dose-dependently lowered cytochrome P450 2E1 activity and protein expression at 23.5-51.2% and 21.4-62.3%, respectively (P<0.05). MA pre-intake decreased subsequent alcohol-induced reactive oxygen species, interleukin-6, tumor necrosis factor-alpha, monocyte chemoattractant protein-1, nitric oxide and prostaglandin E2 production; retained glutathione content; maintained catalase and glutathione peroxidase activities; and declined cyclooxygenase-2 and total nitric oxide synthase activities in liver (P<0.05). Furthermore, MA pre-intake suppressed 17.3-51.7% nuclear factor kappa (NF-κ)B p50, 23.5-58.8% NF-κB p65, 25.6-62.4% p-p38 and 24.1-63.0% p-JNK expression in liver (P<0.05). Histological data indicated that MA intake at test doses attenuated hepatic inflammatory infiltrate. These findings support that maslinic acid is a potent preventive agent against acute alcoholic liver disease.Food and Chemical Toxicology 10/2014; 74. DOI:10.1016/j.fct.2014.09.018 · 2.90 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Abstract The tight glycemic control required to attenuate chronic complications in type 1 diabetes mellitus requires multiple daily injections of bolus insulin which cause hyperinsulinemic edema and hypertension due to Na(+) retention. Reports indicate that pectin insulin (PI)-containing dermal patches sustain controlled insulin release into the bloodstream of streptozotocin (STZ)-induced diabetic rats. This study investigated whether PI dermal patches can improve the impaired renal function in diabetes. PI patches were prepared by dissolving pectin/insulin in deionized water and solidified with CaCl2. Short-term (five weeks) effects of thrice daily treatments with PI patches on renal function and urinary glucose outputs were assessed in diabetic animals. Blood and kidney samples were collected after five weeks for measurements of selected biochemical parameters. Blood was also collected for insulin measurement 6 h following treatments. The low plasma insulin concentrations exhibited by STZ-induced diabetic rats were elevated by the application of insulin-containing dermal patches to levels comparable with control non-diabetic rats. Untreated STZ-induced diabetic rats exhibited elevated urinary glucose, K(+) outputs and depressed urinary Na(+) outputs throughout the 5-week period. Treatment with PI dermal patches increased urinary Na(+) output and reduced urine flow, urinary glucose and K(+) excretion rates in weeks 4 and 5. PI dermal patches increased GFR of diabetic rats with concomitant reduction of plasma creatinine concentrations. Transdermal insulin treatment also decreased the renal expressions of GLUT1 and SGLT1 of STZ-induced diabetic rats. We conclude that PI dermal patches deliver physiologically relevant amounts of insulin that can improve kidney function in diabetes.Renal Failure 10/2014; 37(1):1-9. DOI:10.3109/0886022X.2014.970469 · 0.94 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The efficacy of maslinic acid in the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D) was investigated. Rats were divided into five groups: blank control, model, positive control, high-dose maslinic acid, and low-dose maslinic acid. The IBS-D model was set up by acetic acid-constraint-combined stimulation. Fecal water content, abdominal withdrawal reflex, in vitro colon contraction, and pathological staining and 5-hydroxytryptamine (5-HT) immunohistochemistry of colon were detected and analyzed. The in vivo results showed a significant improvement in the fecal water content; and the abdominal withdrawal reflex times returned to the normal range in the high-dose maslinic acid group. The effects were comparable to those of the positive control group. Low-dose maslinic acid exhibited weak activity. No pathological change was observed in any group in vitro. The susceptibility of colon to acetylcholine (Ach) and 5-HT was restored to normal in high-dose maslinic acid group, and 5-HT-positive enterochromaffin cells were reduced. These indicate that maslinic acid had certain efficacy for IBS-D, and high-dose maslinic acid displayed better effects than low-dose. ©, 2015, South China University of Technology. All right reserved.Modern Food Science and Technology 01/2015; 31(1):16-20. DOI:10.13982/j.mfst.1673-9078.2015.1.004
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.