Oxidative Stress In Diabetic Rats Research Articles

Acute Pre- and Post-administration of Lactiplantibacillus plantarum 2034 and Its Secretory Metabolites Ameliorates Hyperglycaemia, Hyperlipidaemia, and Oxidative Stress in Diabetic Rats.

The global prevalence rate of diabetes in 2021 was 6.1% making diabetes one of the top 10 causes of death. Prolonged use of antidiabetic medications is associated with various side effects; therefore, alternative treatment strategies for diabetes need exploration. The antidiabetic properties of Lactiplantibacillus plantarum 2034 was explored both in in vitro and in vivo studies. Secretory metabolites of probiotic L. plantarum 2034 exhibited alpha-glucosidase, alpha-amylase, and lipase inhibitory activities, in vitro. Further, the antidiabetic efficacy of 2034 was evaluated in streptozotocin-nicotinamide-induced diabetic rats. In the therapeutic model, oral administration of L. plantarum resulted in normalization of body weight, fasting blood glucose, total cholesterol (TC), and liver enzymes, and significant (p < 0.05) reduction in insulin and triglyceride (TG) levels. Histological evaluation of pancreas, liver, and kidney showed restoration of normal architecture in probiotic-treated group. Similarly, in a preventive + therapeutic model, 14days of pre-administration of 2034 in pre, pre + post, and cell-free supernatant resulted in significant reduction in glucose, TG, TC, and liver biochemistry of diabetic rats as compared to untreated diabetic rats. An oral glucose tolerance test showed that the glucose levels normalized within 90min in all the treated groups. Further, the oxidative stress parameters were also studied that showed that in all the treated groups, the concentration of antioxidant enzymes significantly (p < 0.05) increased as compared to diabetic untreated rats. Thus, administration of L. plantarum 2034 and its metabolites successfully ameliorated hyperglycaemia and hypercholesterolemia in both the models probably due to inhibition of gut enzymes and by increasing the concentration of liver antioxidant enzymes.

Tannins-enriched fraction of TeMac™ protects against aluminum chloride induced Alzheimer's disease-like pathology by modulating aberrant insulin resistance and alleviating oxidative stress in diabetic rats

Ethnopharmacological relevanceAlzheimer's disease is the most common neurodegenerative disease with therapeutic limitations. Insulin resistance plays a role in the progression of Alzheimer's disease. Therapies that modulate insulin secretion and signaling, as well as oxidative stress in the brain are now being investigated for their potential role in the prevention of Alzheimer's disease (AD). Terminalia macroptera (Combretaceae) is a plant that different parts have been used traditionally for the treatment of metabolic and neurological conditions. Previous study has indicated that the crude extract exhibit anti-diabetic property. In addition, the plant is a rich source of tannins, phenolic acids, flavonoids, triterpenes. However, there is no study on its protective effect against biochemical alterations of AD in diabetic rats. Aim of the studyThe present research study investigated the neuroprotective effects of TeMac™ on Alzheimer-like pathology induced by aluminum chloride (AlCl3) in diabetic rats. MethodsA phytochemical analysis of TeMac™ was carried out to quantify tannins. The potential effect of the tannins-enriched fraction (TEF) of TeMac™ to prevent the formation of senile plaques was conducted by its ability to inhibit the activities of β-secretase (EC 3.4.23.46), monoamine oxidase A (EC 1.4.3.4) and the fibrillation of Aβ. A diabetic model was induced from female Wistar rats by a single intraperitoneal injection of streptozotocin (STZ, 35 mg/kg BW). After that, the blood glucose level was measured to confirm the induction of diabetes. Three days after induction, animals received AlCl3 (75 mg/kg BW) alone (AD control) or concomitantly with 400 mg/kg BW of TEF of TeMac™ or 5 mg/kg BW Daonil by daily gavage for 42 days. At the end of the experiment, rats were sacrificed, blood and brains were collected. The levels of amyloid fibrils, glucose, albumin and the activities of DPP4, β-secretase and phosphatase, and markers of oxidative stress in the brain were assessed. ResultsTEF of TeMac™ displays a potential ability to inhibit the activities of β-secretase, monoamine oxidase, and Aβ fibrillation. Treatment with TEF of TeMac™ significantly inhibited DPP4 and BACE1 activities and reduced brain glucose and amyloid fibril levels, and improved cerebral albumin levels and modulated oxidative stress markers. ConclusionOur findings indicate that TEF of TeMac™ prevents Alzheimer's-type pathology linked to insulin resistance in rats. TEF of TeMac™ may be a potential drug candidate for the treatment of diabetes-associated cognitive impairment.

Chrysophyllum albidum (African star apple) Fruit-Skin Attenuates Hyperglycemia-Mediated Oxidative Stress in Experimental Diabetic Rats

Diabetes mellitus, a chronic metabolic disturbance characterized by hyperglycemia has become a health problem affecting millions of people worldwide. Hyperglycemia mediated oxidative stress performs a key role in diabetic complications. The fruit-skin of Chrysophyllum albidum (African star apple) has been reported to have anti-hyperglycemic, hypolipidemic and in vitro antioxidant properties, but its effect on oxidative damage in diabetic animals has not been well investigated. This study investigated the effect of Chrysophyllum albidum fruit-skin (CAFS) in mitigating hyperglycemia induced oxidative stress in diabetic rats. Oxidative stress markers included superoxide dismutase (SOD) and catalase (CAT), lipidperoxidation status using malondialdehyde and non-enzymatic antioxidants in serum, hepatic and pancreatic tissues. Non-diabetic and streptozotocin-diabetic rats were compared after 4 weeks of treatment. The diabetic untreated group showed significant (p&lt; 0.05) elevation of malondialdehyde and depression of non-enzymatic antioxidants levels, while suppressing SOD and CAT activities in serum, hepatic and pancreatic tissues when compared to normal rats. CAFS supplemented diet treatment ameliorated these metabolic disturbances and increased the activities of hepatic and pancreatic SOD from 0.28±0.25 to 0.61±0.13 Unit/mg protein and 0.08±0.01 to 0.15±0.01 Unit/mg protein respectively and CAT from 0.21±0.06 to 0.81±0.17 Unit/mg protein and 0.07±0.01 to 0.50±0.15 Unit/mg protein respectively. The findings suggest that CAFS treatment in diabetic rats exerts a protective effect via attenuation of oxidative stress mediated by hyperglycemia and improves the antioxidant status.&#x0D;

The effect of banana (Musaceae) and onion (Allium cepa) on liver functions and oxidative stress of diabetic rats

The effect of banana (Musaceae) and onion (Allium cepa) on liver functions and oxidative stress of diabetic rats

Salbutamol Attenuates Diabetic Skeletal Muscle Atrophy by Reducing Oxidative Stress, Myostatin/GDF-8, and Pro-Inflammatory Cytokines in Rats.

Type 2 diabetes is a metabolic disorder that leads to accelerated skeletal muscle atrophy. In this study, we aimed to evaluate the effect of salbutamol (SLB) on skeletal muscle atrophy in high-fat diet (HFD)/streptozotocin (STZ)-induced diabetic rats. Male Sprague Dawley rats were divided into four groups (n = 6): control, SLB, HFD/STZ, and HFD/STZ + SLB (6 mg/kg orally for four weeks). After the last dose of SLB, rats were assessed for muscle grip strength and muscle coordination (wire-hanging, rotarod, footprint, and actophotometer tests). Body composition was analyzed in live rats. After that, animals were sacrificed, and serum and gastrocnemius (GN) muscles were collected. Endpoints include myofibrillar protein content, muscle oxidative stress and antioxidants, serum pro-inflammatory cytokines (interleukin-1β, interleukin-2, and interleukin-6), serum muscle markers (myostatin, creatine kinase, and testosterone), histopathology, and muscle 1H NMR metabolomics. Findings showed that SLB treatment significantly improved muscle strength and muscle coordination, as well as increased lean muscle mass in diabetic rats. Increased pro-inflammatory cytokines and muscle markers (myostatin, creatine kinase) indicate muscle deterioration in diabetic rats, while SLB intervention restored the same. Also, Feret's diameter and cross-sectional area of GN muscle were increased by SLB treatment, indicating the amelioration in diabetic rat muscle. Results of muscle metabolomics exhibit that SLB treatment resulted in the restoration of perturbed metabolites, including histidine-to-tyrosine, phenylalanine-to-tyrosine, and glutamate-to-glutamine ratios and succinate, sarcosine, and 3-hydroxybutyrate (3HB) in diabetic rats. These metabolites showed a pertinent role in muscle inflammation and oxidative stress in diabetic rats. In conclusion, findings showed that salbutamol could be explored as an intervention in diabetic-associated skeletal muscle atrophy.

Cannabinoid receptor 2 (CB2) agonists and L-arginine ameliorate diabetic nephropathy in rats by suppressing inflammation and fibrosis through NF-κβ pathway.

Diabetic nephropathy (DN) is a condition that leads to end-stage chronic kidney disease characterized by inflammation and a deficiency ofnitric oxide (NO).Cannabinoid receptor (CB2) activation by specific agonist reduces nuclear factor kappa beta (NF-κβ) expression. Beta caryophyllene (BCP), a natural CB2 receptor activator, protects kidney function in several diseases. L-Arginine (LA) modulates several physiological processes by donating nitric oxide (NO). Hence, we tested a novel BCP-LA combination to treat DN and investigated its molecular mechanisms. BCP, LA, and combinations of both were evaluated in LPS-induced RAW 264.7 macrophage inflammation as well as in streptozotocin (55mg/kg)-induced diabetes in SD rats. Diabetic rats were administered200 mg/kg of BCP, 100mg/kg of LA, and combination of both orally for 28days. Biochemical markers and inflammatory cytokines were assessed in plasma; also, kidney tissue was examined for renal oxidative stress injury, NF-κβ expression, and histology. After 28days of treatment, BCP and LA combination significantly lowered plasma glucose levels than the disease control group. BCP and LA also normalized renal markers and oxidative stress of diabetic rats. Plasma and RAW macrophage cell lines showed reduced levels of IL-6 and TNF-α (P < 0.001). Histopathological evaluations revealed that BCP and LA together decreased renal fibrosis and collagen deposition also improved nephrotic indices. Meanwhile, the effect of BCP and LA together significantly reduced the NF-κβ (P < 0.01) against diabetic rats. These results indicate that the innovative regimen BCP with LA may be a therapeutic treatment for DN, as it protects kidney tissue from diabetes via NF-κβ inhibition.

Ameliorative effects of phlorotannin-rich fraction of Sargassum tenerrimum in high-fat diet and low dose streptozotocin-induced metabolic changes and oxidative stress in diabetic rats

Introduction: Type 2 diabetes mellitus (T2D) is a progressing polygenic disease demanding a multitargeted treatment strategy. Sargassum tenerrimum (ST) is a marine brown alga with potentially bioactive chemicals that could be used as innovative biotherapeutics for diabetes treatment. The current research examined the potential of the phlorotannin-rich fraction from S. tenerrimum (PST) to mitigate diabetes in Wistar albino rats induced with high-fat diet (HFD) and streptozotocin (STZ) administration. Methods: Diabetic rats were given PST (200 and 400 mg/kg) or metformin (250 mg/kg) orally three weeks, and followed by the measurements of insulin, glycemic factors, biological markers of oxidative stress, tumor necrosis factor-alpha (TNF-α), as well as hepatic and pancreatic histopathological changes. Results: PST treatment significantly decreased fasting blood glucose, insulin resistance, lipid profile, hepatic profile, and TNF- α levels and improved serum insulin and glucose tolerance in diabetic rats. In the skeletal muscles of diabetic rats, PST led to a significant rise in antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) reductase, and a decrease in lipid peroxidation. Furthermore, PST treatment significantly reduced pancreatic-cell damage and hepatic fatty accumulation. PST was more efficacious at 400 mg/kg exhibiting a dose-dependent effect. Conclusion: PST improves glucolipid metabolism in HFD and STZ-induced diabetic rats, probably by reducing hyperglycemia, insulin resistance, dyslipidemia, oxidative stress, inflammation, and damage to pancreatic and hepatic architectures. The findings suggest that PST has a curative impact on diabetes mellitus type 2 and represents a new subject of study for the treatment of diabetes naturally.

Antihyperglycemic activity of colostrum peptides

Peptides of plant and animal origin have good anti-diabetic prospects. The research objective was to use bovine colostrum peptides to reduce hyperglycemia in diabetic rats.&#x0D; Bovine colostrum peptides were obtained by trypsin hydrolysis of colostrum proteins with preliminary extraction of triglycerides. The study involved four groups of Wistar rats with seven animals per group. Group 1 served as control; group 2 received 300 mg/kg of trypsin hydrolysate of bovine colostrum as part of their daily diet for 30 days. Groups 3 and 4 had diabetes mellitus caused by intraperitoneal injections of 110 mg/kg of nicotinamide and 65 mg/kg of streptozotocin. Group 4 also received 300 mg/kg trypsin hydrolysate of bovine colostrum intragastrically five times a week for 30 days.&#x0D; Three peptides were isolated from the trypsin hydrolysate of bovine colostrum and tested for the sequence of amino acids and molecular weight. Their identification involved the Protein NCBI database, followed by 2D and 3D modeling, which revealed their chemical profile, pharmacological properties, and antioxidant activity. The diabetic rats treated with colostrum peptides had lower glucose, glycated hemoglobin, malondialdehyde, and catalase activity but a higher content of glutathione in the blood. Their leukocytes and erythrocytes also demonstrated less deviation from the standard. The antioxidant effect of colostrum protein hydrolysate depended on a peptide with the amino acid sequence of SQKKKNCPNGTRIRVPGPGP and a mass of 8.4 kDa.&#x0D; Colostrum peptides reduced hyperglycemia and oxidative stress in diabetic rats. The research revealed good prospects for isolating individual colostrum peptides to be tested for antidiabetic properties.

The effects of ethanol extract of Punica granatum L. peel on the testis damage induced by diabetes in rats

In this study, it was aimed to determine the effect of ethanol extract of Punica granatum L. peel (PGE) on oxidative stress and histopathological values in blood and testis tissue in rats with diabetes. In present study used twenty-eight male Sprague Dawley rats were randomly divided into four equal groups containing of seven rats per group. Group 1; peros physiological saline to the rat, Group 2; STZ 60 mg/kg/IP single dose, Group 3; PGE 10 mg/kg/20days/peros, Group 4; STZ as 60 mg/kg/IP + PGE 10 mg/kg/20days/peros. After the end of the experimental procedure, the rats were sacrificed, blood and testicular tissues were taken, and biochemical and histopathological examinations were performed. The administration of PGE was shown that the activities of CAT, SOD, GPx and GSH increased and the levels of MDA decreased in diabetic rats. Oral administration of PGE reduced the levels of LPO and improved the antioxidant activity in plasma and testis tissues while compared with the Groups 4. Histopathological examination of testicular tissues in the Group 2 is revealed edema in the intertubular spaces, thinning of the tubule walls due to diminished spermatocytes in the walls of the seminiferous tubules and severe degenerative and necrotic changes in spermatocytes. These changes were found to be very mild in Group 4. According to immunohistochemical findings, in Group 2, caspase 3 expression was intensely expressed in spermatocytes. As a result, it was observed that Punica granatum L. peel extract strengthened antioxidant defense and reduced oxidative stress in diabetic rats.

The effects of tempe protein isolate from non-germinated and germinated soybean on oxidative stress in diabetic rats

Diabetes mellitus (DM) patients tend to be more susceptible to the COVID-19 virus. Evidence suggests that infection with the COVID-19 virus leads to increase reactive oxygen species (ROS) production. Moreover, hyperglycaemic conditions also produce excess ROS. Those can lead to oxidative stress in DM patients. This study aimed to prevent oxidative stress by using innovative functional food called tempe protein isolates, which were isolated from both non-germinated soybean (TPIN) and germinated soybeans (TPIG). TPIN, TPIG and commercial soy protein isolate (CSPI) were given 900 mg/kg BW to DM rats for 28 days. The DM rats were modelled by inducing an alloxan dose of 110 mg/kg BW intraperitoneally. Results showed there were no significant differences (p&gt;0.05) in feed intake and blood profile. TPIN significantly prevented excessive weight loss and reduced blood glucose (p&lt;0.05) better than TPIG and CSPI. TPIN and TPIG significantly (p&lt;0.05) prevent the formation of MDA in the kidney, increase the activity of the SOD enzyme in both liver and kidney tissues and increase Cu,Zn-SOD antioxidant. This study concluded that the administration of TPIG and TPIN could prevent liver and kidney tissue damage by free radicals. Furthermore, TPIN has better potential than TPIG to prevent oxidative stress.

Nephroprotective effect of milkfish, patin, and snakehead fish oil by suppressing inflammation and oxidative stress in diabetic rats

Diabetic nephropathy (DN) has been linked to a number of long-term problems caused by diabetes mellitus. Inflammatory and oxidative stress pathways contribute to DN development and progression. Many studies have shown the preventive advantages of diets rich in substances like anti-inflammatory and antioxidant elements like omega-3 fatty acids (n-3 FA) in preventing DN. Milkfish (Chanos chanos F.), patin (Pangasius micronema Blkr.), and snakehead fish (Chana striata Bloch) are types of fish oils that are known to contain n-3 FA. This study aims to prove the nephroprotective effect of the three types of fish oil in a rat model of diabetes mellitus. Thirty male rats were used in this study. The animals were randomly divided into six groups (n = 5): the non-diabetic group, the diabetes mellitus group, the diabetic with 150 mg/kg metformin orally group, the diabetic with 1000 mg/kg milkfish oil orally group, the diabetic with 1000 mg/kg patin fish oil orally group, and the diabetic with 1000 mg/kg snakehead fish oil orally group. Diabetes models were induced using 65 mg/kg streptozotocin and 230 mg/kg nicotinamide intraperitoneally. The test was carried out for 8 weeks, followed by the observation of the biochemical profiles of blood, urine, oxidative stress, and the immunohistochemistry of the kidneys. A normally and homogeneously distributed test followed by a one-way analysis of variance (ANOVA) and the LSD post hoc test were used to look at the data. At p≤0.05, the data was considered statistically significant. The results showed that serum creatinine levels did not differ significantly after the administration of milkfish, catfish, and snakehead fish oil for 8 weeks (p≥0.05). Different results were shown where the levels of serum BUN, uric acid, urine urea, and microalbumin urine were significantly different after administration of the three types of fish oil (p≤0.05). The same results were shown in oxidative stress (superoxide dismutase, glutathione, and malondialdehyde) and inflammation (interleukin-6 and tumor necrosis factor-α) profiles (p≤0.05). The conclusion is that milkfish, patin, and snakehead fish oils have moderate nephroprotection by suppressing inflammation and oxidative stress.

Actinidia deliciosa as a complemental therapy against nephropathy and oxidative stress in diabetic rats

This study aimed to evaluate the anti-hyperglycemic and antioxidant role of Actinidia deliciosa (kiwifruits) aqueous extract in streptozotocin-treated rats. Animals were distributed into; control, A. deliciosa aqueous extract (ADAE; 1 g/kg orally), streptozotocin (STZ; 50 mg/kg, i.p, single dose), and STZ plus ADAE, respectively. Results showed that ADAE had high antioxidant and radical scavenging potency. Elevation in blood sugar level, lipid peroxidation (LPO), kidney function biomarkers, and perturbations in hematological parameters were observed in diabetic rats. While, enzymatic and non-enzymatic antioxidants, protein content, and alkaline phosphatase (ALP) activity declined. Furthermore, histological, immunohistochemical alpha-smooth muscle actin immunoreactivity (α-SMA-ir) and histochemical (collagen, total protein, DNA, and RNA) alterations were observed in rat kidneys. Moreover, STZ produced upregulation of inflammatory associated genes (tumor necrosis factor-alpha; TNF-α and transforming growth factor β1; TGF-β1) and triggered apoptosis by upregulating apoptotic related gene [Bcl2-associated X protein (Bax)] and downregulating anti-apoptotic related gene B-cell lymphoma-2 (Bcl-2) based on real-time PCR data. Moreover, diabetic rats administered with ADAE showed significant restoration in LPO, antioxidant status, and biochemical indices besides tissue architecture, and genes improvement regarding STZ group. Conclusively, A. deliciosa has a valuable ameliorative influence and can restore glucose levels and improve kidney dysfunction in diabetic rats.

Identification of major phenolic compounds of Aloe vera and its protective effect on ovaries under oxidative stress in diabetic rats

Identification of major phenolic compounds of Aloe vera and its protective effect on ovaries under oxidative stress in diabetic rats

Clitoria ternatea extract-loaded chitosan nanoparticles ameliorate diabetes and oxidative stress in diabetic rats

Clitoria ternatea extract-loaded chitosan nanoparticles ameliorate diabetes and oxidative stress in diabetic rats

EVALUATION OF ROLE OF FICUS BENGALENSIS IN MODULATION OF COGNITIVE IMPAIRMENT AND OXIDATIVE STRESS IN DIABETIC RATS

Objectives: Our objective was to study the effects of Ficus benghalensis on cognitive behavior and oxidative stress in diabetic rats and to compare with vitamin C and glimepiride. Methods: Wistar rats of either sex randomized into five groups of diabetic rats by streptozocin (STZ), five groups of non-diabetic rats (distilled water) (n=10). Subgroup division (F. benghalensis dose I and II, i.e., 50 mg/kg and 100 mg/kg; Vitamin C 100 mg/kg and glimepiride 0.5 mg/kg) were done. Each drug was given to one diabetic and one non-diabetic group. Other set served as control. Assessment of blood glucose, cognitive function (using continuous avoidance apparatus and Morris water maze test), and oxidative stress (measuring Malondialdehyde (MDA), reduced glutathione (GSH) levels) were done on Day 0 and 30. The acquisition phase of cognitive behavior tests was assessed on 0, 14, and 29 days and retention phase was assessed on 1, 15, and 30 day. Results: As compared to control group, F. benghalensis dose I, dose II, and glimepiride showed significant decrease (p&lt;0.001) in blood glucose. F. benghalensis dose I, dose II, vitamin C, and glimepiride group showed significant decrease in acquisition and retention of transfer latency on 29 and 30 days. Significant increase in retention of step-down latency on 30 day was shown by both the doses of F. benghalensis. Both doses of F. benghalensis, vitamin C and glimepiride group showed significant increase in retention of Quadrant-time in comparison to control on 30 days. Significant decrease in brain MDA levels while a significant increase in brain GSH levels was observed in all groups except control. Conclusion: F. benghalensis reverses behavioral and biochemical changes induced by STZ and effects are comparable with that of vitamin C and glimepiride.

Vitamin E treatment in insulin-deficient diabetic rats reduces cardiac arrhythmias and mortality during severe hypoglycemia.

In people with type 1 diabetes, hypoglycemia can induce cardiac arrhythmias. In rodent experiments, severe hypoglycemia can induce fatal cardiac arrhythmias, especially so in diabetic models. Increased oxidative stress associated with insulin-deficient diabetes was hypothesized to increase susceptibility to severe hypoglycemia-induced fatal cardiac arrhythmias. To test this hypothesis, Sprague-Dawley rats were made insulin deficient with streptozotocin and randomized into two groups: 1) control (n = 22) or 2) vitamin E treated (four doses of α-tocopherol, 400 mg/kg, n = 20). Following 1 week of treatment, rats were either tested for cardiac oxidative stress or underwent a hyperinsulinemic-severe hypoglycemic (10-15 mg/dL) clamp with electrocardiogram recording. As compared with controls, vitamin E-treated rats had threefold less cardiac oxidative stress, sixfold less mortality due to severe hypoglycemia, and sevenfold less incidence of heart block. In summary, vitamin E treatment and the associated reduction of cardiac oxidative stress in diabetic rats reduced severe hypoglycemia-induced fatal cardiac arrhythmias. These results indicate that in the setting of diabetes, pharmacological treatments that reduce oxidative stress may be an effective strategy to reduce the risk of severe hypoglycemia-induced fatal cardiac arrhythmias.NEW & NOTEWORTHY For people with type 1 diabetes, severe hypoglycemia can be fatal. We show in our animal model that insulin-deficient diabetic rats have fatal cardiac arrhythmias during severe hypoglycemia that are associated with increased cardiac oxidative stress. Importantly, treatment with vitamin E, to reduce oxidative stress, decreased fatal cardiac arrhythmias during severe hypoglycemia.

Effects of zinc supplementation on glycemic control and oxidative stress in experimental diabetes: A systematic review.

Diabetes mellitus (DM), an important public health problem worldwide, can cause imbalances in the homeostasis of trace elements such as zinc (Zn). It is possible that an adequate nutritional status related to nutrients is essential for the normal functioning of antioxidant defense systems, and any change in the concentration of these substances could increase the chances of DM complications. To present a review on the effect of zinc supplementation on glycemic control and oxidative stress in experimental diabetes. This is a systematic review of articles that investigated the effects of zinc supplementation on glycemic control and oxidative stress in diabetic rats. The PICOS strategy was used for the development of the research question, and the Syrcle tool for the quality assessment of the studies included in the review. Articles available in the PubMed, Scopus, and Web of Science databases were included without restriction on year of publication. The Syrcle tool was used to assess the risk of bias of the included studies. Fifteen studies were included in the review, seven of which evaluated glycemic control and oxidative stress after zinc supplementation, five only oxidative stress and three only glycemic control after zinc treatment. In all the studies included, diabetes was induced by the administration of streptozotocin (STZ) at doses ranging from 40 to 100mg/kg. Zinc supplementation was made in the diet or drinking water or by gavage or intraperitoneal injection. The most used doses were 100mg/kg of body weight by gavage and 0.32 and 0.64g/kg in diet. The supplementation period ranged from 14 days to 8 weeks. Six studies revealed that zinc supplementation decreased fasting blood glucose as well as insulin resistance; nine studies included in this review reported decreased MDA concentration; in five studies, there was an increase in the activity of antioxidant enzymes (GPx, SOD, GSH and catalase); and one of the studies reported a reduction in glycated hemoglobin. Zinc supplementation improved hyperglycemia and revealed a protective potential against oxidative stress associated with experimental diabetes.

Insulin supplemented with phenolic fraction concentrates displays anxiolytic and antidepressant-like properties with reductions of oxidative brain damage in chronically stressed diabetic rats

Introduction: The current study aimed to investigate if insulin supplemented with phenolic fraction concentrates (PFC) improves chronic hyperglycemia-related behavioral changes by mitigating oxidative stress in diabetic rats exposed to chronic mild stress (CMS). Methods: Experimental type 1 diabetes mellitus (T1DM) was established by a single intraperitoneal injection of streptozotocin (STZ, 65 mg/kg). After diabetes confirmation, rats were treated with insulin supplemented with PFC and exposed to two unpredictable mild stressors per day for 12 weeks. Body weight changes, fasting blood glucose (FBG), and corticosterone levels were evaluated. The behavioral tests were performed to evaluate anhedonia, anxiety, and depressive-like behaviors. Twenty-four hours after behavioral tests, all rats were anesthetized, and the blood was collected for the analysis of lipid, hepatic, and renal parameters. Finally, the brain areas (striatum, hippocampus, and prefrontal cortex), pancreas, and adrenal glands were dissected for the analysis of oxidative stress markers. Results: The results of this study revealed that treatment with insulin supplemented with PFC for 12 weeks significantly enhanced antioxidant defenses (catalase [CAT] and superoxide dismutase [SOD]) and reduced oxidative stress damage (nitric oxide and malondialdehyde [MDA]), especially in brain regions (prefrontal cortex, hippocampus, and striatum) in stressed diabetic rats (P &lt; 0.001). This combination also ameliorated the corticosterone level (P &lt; 0.001) as well as glucose homeostasis (P &lt; 0.001) and lipid parameters (P &lt; 0.001), which are markedly altered in T1D associated with stress. Conclusion: The associated treatment possesses important anxiolytic and antidepressant-like effects in this rat model, which might be mainly mediated by its capacity to protect brain cells against reactive oxygen species (ROS) triggered by T1DM and/or chronic stress.

L-carnitine Attenuates DNA Damage and Oxidative Stress in Diabetic Animals

Background: Diabetes is a metabolic disorder characterized by high plasma glucose levels. In this disease, increased production of reactive oxygen species (ROS) results in DNA damage and multiple complications. L-carnitine (LC) has shown a potent antioxidant activity that may reduce oxidative stress. Objectives: This study aims at assaying the effect of LC on DNA damage in streptozotocin-induced diabetic rats and evaluating the changes in antioxidant markers and liver function enzymes after the administration of LC . Methods: In the present study, for induction of diabetes, we injected a single dose of streptozotocin (65 mg/kg) by the intraperitoneal route, and diabetic rats were treated with LC 200, 300, and 400 mg/kg daily for 3 weeks. We detected the DNA damage at 7, 14, and 21 days after induction diabetes by the comet assay method. The blood glucose level, plasma alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were tested. Also, we measured the activity levels of superoxide dismutase (SOD) and intracellular glutathione (GSH). Results: The results of this study demonstrated the increasing amount of DNA damage with the amount and duration of hyperglycemia. L-carnitine treatment significantly decreased the parameters of genotoxicity such as % DNA in the tail, tail length, and tail moment over time. Moreover, the treatment of diabetic rats with LC 300 and 400 mg/kg/day after 21 days led to a remarkable decrease in blood glucose than diabetic rats. Also, we observed that LC can ameliorate enzyme liver function and reduce oxidative stress via enhancement of GSH and SOD levels. Conclusions: The results of this study indicated the protective effect of LC against DNA damage and oxidative stress in diabetic rats.

Antioxidant Potential of Non-Extractable Fractions of Dried Persimmon (Diospyros kaki Thunb.) in Streptozotocin-Induced Diabetic Rats.

Oxidative stress causes the progression of diabetes and its complications; thus, maintaining the balance between reactive oxygen species produced by hyperglycemia and the antioxidant defense system is important. We herein examined the antioxidant potential of non-extractable fractions of dried persimmon (NEP) against oxidative stress in diabetic rats. Rats with streptozotocin-induced type 1 diabetes (50 mg/kg body weight) were administered NEP for 9 weeks. Antioxidant enzyme activities and concentration of antioxidants in liver tissues were analyzed with a microplate reader. Extensor digitorum longus (EDL) and soleus muscle fibers were stained with succinate dehydrogenase and muscle fiber sizes were measured. The administration of NEP increased the body weight of diabetes rats. Regarding antioxidant activities, the oxygen radical absorbance capacity and superoxide dismutase activity in liver tissues significantly increased. In addition, increases in glutathione peroxidase activity in liver tissues and reductions in the cross-sectional area of EDL muscle fibers were significantly suppressed. In these results, NEP improved the antioxidant defense system in the liver tissues of diabetic rats, in addition to attenuating of muscle fibers atrophy against oxidative damage induced by hyperglycemia.