Vanillylacetone attenuates cadmium chloride-induced hippocampal damage and memory loss through up-regulation of nuclear factor erythroid 2-related factor 2 gene and protein expression.

JOURNAL/nrgr/04.03/01300535-202412000-00030/figure1/v/2024-04-08T165401Z/r/image-tiff Memory loss and dementia are major public health concerns with a substantial economic burden. Oxidative stress has been shown to play a crucial role in the pathophysiology of hippocampal damage-induced memory impairment. To investigate whether the antioxidant and anti-inflammatory compound vanillylacetone (zingerone) can protect against hippocampal damage and memory loss induced by cadmium chloride (CdCl2) administration in rats, we explored the potential involvement of the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, which is known to modulate oxidative stress and inflammation. Sixty healthy male Wistar rats were divided into five groups: vehicle-treated (control), vanillylacetone, CdCl2, vanillylacetone + CdCl2, vanillylacetone + CdCl2 + brusatol (a selective pharmacological Nrf2 inhibitor) groups. Vanillylacetone effectively attenuated CdCl2-induced damage in the dental gyrus of the hippocampus and improved the memory function assessed by the Morris Water Maze test. Additionally, vanillylacetone markedly decreased the hippocampal tissue levels of inflammatory biomarkers (interleukin-6, tumor necrosis factor-α, intracellular cell adhesive molecules) and apoptosis biomarkers (Bax and cleaved caspase-3). The control and CdCl2-treated groups treated with vanillylacetone showed reduced generation of reactive oxygen species, decreased malondialdehyde levels, and increased superoxide dismutase and glutathione activities, along with significant elevation of nuclear Nrf2 mRNA and protein expression in hippocampal tissue. All the protective effects of vanillylacetone were substantially blocked by the co-administration of brusatol (a selective Nrf2 inhibitor). Vanillylacetone mitigated hippocampal damage and memory loss induced by CdCl2, at least in part, by activating the nuclear transcription factor Nrf2. Additionally, vanillylacetone exerted its potent antioxidant and anti-inflammatory actions.

Improvement of Na+-K+ ATPase Activity and Gene Expression Associated with Glomerular Ultrastructural Protection in Diabetic Nephropathy by Acacia senegal: Role of Oxidative Stress Disturbances / Mejora de la actividad Na+-K+ ATPasa y la Expresión Génica Asociada con la Protección Ultraestructural Glomerular en la Nefropatía Diabética por Acacia senegal: Papel de las Alteraciones del Estrés Oxidativo

SUMMARY: This study assessed the effects of Acacia Senegal (AS) combined with insulin on Na+/K+-ATPase (NKA) activity and mRNA expression, serum glucose, renal function, and oxidative stress in a rat model of diabetic nephropathy (DN). Sixty rats were equally divided into six groups: normal control, normal+AS, diabetic (DM), DM+insulin, DM+AS, and DM+insulin+AS groups. Diabetes mellitus (type 1) was induced by a single injection of streptozotocin (65 mg/kg), and insulin and AS treatments were carried until rats were culled at the end of week 12. Serum glucose and creatinine levels, hemoglobin A1c (HbA1c) were measured. Renal homogenate levels of NKA activity and gene expression, malondialdehyde, superoxide dismutase (SOD), catalase and reduced glutathione (GSH) were evaluated as well as kidney tissue histology and ultrastructure. Diabetes caused glomerular damage and modulation of blood and tissue levels of creatinine, glucose, HbA1c, malondialdehyde, NKA activity and gene expression, SOD, catalase and GSH, which were significantly (p<0.05) treated with AS, insulin, and insulin plus AS. However, AS+insulin treatments were more effective. In conclusion, combined administration of AS with insulin to rats with DN decreased NKA activity and gene expression as well as oxidative stress, and improved glycemic state and renal structure and function.

Este estudio evaluó los efectos de Acacia senegal (AS) combinada con insulina sobre la actividad Na+/K+- ATPasa (NKA) y la expresión de ARNm, la glucosa sérica, la función renal y el estrés oxidativo en un modelo de nefropatía diabética (ND) en ratas. Sesenta ratas se dividieron equitativamente en seis grupos: control normal, normal+AS, diabética (DM), DM+insulina, DM+AS y DM+insulina+AS. La diabetes mellitus (tipo 1) se indujo mediante una única inyección de estreptozotocina (65 mg/kg), y los tratamientos con insulina y AS se llevaron a cabo hasta que las ratas fueron sacrificadas al final de la semana 12. Se midieron niveles séricos de glucosa y creatinina, hemoglobina A1c (HbA1c). Se evaluaron los niveles de homogeneizado renal de actividad NKA y expresión génica, malondialdehído, superóxido dismutasa (SOD), catalasa y glutatión reducido (GSH), así como la histología y ultraestructura del tejido renal. La diabetes causó daño glomerular y modulación de los niveles sanguíneos y tisulares de creatinina, glucosa, HbA1c, malondialdehído, actividad y expresión génica de NKA, SOD, catalasa y GSH, los cuales fueron tratados significativamente (p<0,05) con AS, insulina e insulina más AS. Sin embargo, los tratamientos con AS+insulina fueron más efectivos. En conclusión, la administración combinada de AS con insulina a ratas con DN disminuyó la actividad de NKA y la expresión genética, así como el estrés oxidativo, y mejoró el estado glucémico y la estructura y función renal.

Acacia senegal inhibits diabetic nephropathy ultrastructure alteration and renal biomarkers changes in rats / Acacia senegal inhibe la alteración de la ultraestructura de la nefropatía diabética y los cambios en los biomarcadores renales en rata

SUMMARY: Diabetic nephropathy (DN) is the most common complication of diabetes. Several studies have been done in a trial to protect against this problem at the ultrastructure level. This study investigates the protective effect of oral administration of Acacia senegal (AS) against the development of DN. Sixty male albino rats were randomly divided into six groups: control, Acacia senegal control, Diabetic untreated, diabetic insulin-treated, Diabetic AS treated, and Diabetic insulin and AS combined treated groups. Plasma glucose, HbA1c, serum Albumin, creatinine, urine creatinine was measured using specific kits. Determinations of creatinine clearance and blood pressure were done. The renal tissues of both kidneys were prepared to investigate under both light (LM) and electron microscope (EM). Ultrastructure examination of renal rats tissue of diabetic untreated rats showed the destruction of the glomerular basement membrane and endothelial cells together with hemorrhage in glomerular capsules (Bowman's capsules). On the other side, both LM and EM revealed improving the endothelial cells and the other glomerular capsules structures, especially with the combined treated group, which confirmed the improvement of the biochemical investigation in the study. In conclusion, from the present study, using the oral AS together with SC insulin could be protected against the development of DN.

RESUMEN: La nefropatía diabética (ND) es la complicación más común de la diabetes. Se han realizado varios estudios de ensayo para abordar esta dificultad a nivel de ultraestructura. Este estudio investiga el efecto protector de la administración oral de Acacia senegal (AS) contra el desarrollo de la ND. Se dividieron sesenta ratas albinas machos aleatoriamente en seis grupos: control, control de Acacia senegal, diabéticos no tratados, diabéticos tratados con insulina, diabéticos tratados con AS y grupos tratados con compuesto de insulina diabética + AS. Se midieron utilizando kits específicos, glucosa plasmática, HbA1c, albúmina sérica, creatinina en sangre y en orina. Se registraron la creatinina y la presión arterial. Los tejidos renales de ambos riñones se prepararon para investigar tanto con microscopio óptico (MO) como electrónico (ME). El examen de la ultraestructura del tejido renal de ratas diabéticas no tratadas mostró la destrucción de la membrana basal glomerular y las células endoteliales junto con hemorragia en las cápsulas glomerulares (cápsulas de Bowman). Por otro lado, tanto MO como ME revelaron una mejora de las células endoteliales y las estructuras capsulares glomerulares, en el grupo tratado con el compuesto, lo que confirmó la mejora de la investigación bioquímica. En conclusión, el uso de AS oral en combinación con insulina podría proteger contra el desarrollo de ND.

Maslinic Acid Protects against Streptozotocin-Induced Diabetic Retinopathy by Activating Nrf2 and Suppressing NF-κB.

This study tested the protective effect of maslinic acid (MA) against diabetic retinopathy (DR) in rats with type 1 diabetes mellitus (T1DM) and investigated possible mechanisms of action. DM was introduced by streptozotocin (STZ) (65 mg/kg, i.p.). Control and STZ (T1DM) were divided into 2 subgroups, which received either the vehicle or MA (80 mg/kg). Serum, pancreases, and retinas were collected for further use. MA significantly reduced fasting glucose levels in the control and T1DM rats but enhanced fasting insulin levels and partially increased the size of the islets of Langerhans and the number of ß-cells in T1DM rats. In addition, MA significantly improved the retina structure by preventing the reduction in the area between the inner and outer limiting membranes (ILM and OLM, respectively) and increasing the number of cells forming the ganglion cell layer (GCL), inner nuclear layer (INL), and outer nuclear layer (ONL). Associated with these effects, MA significantly reduced the total levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), as well as the nuclear levels of NF-κB p65, mRNA levels of Bax, and protein levels of cleaved caspase-3 in the retinas of T1DM rats. However, MA significantly lowered levels of reactive oxygen species (ROS) and malondialdehyde (MDA) but significantly increased the nuclear levels of Nrf2, protein levels of Bcl2, and total levels of superoxide dismutase (SOD) and reduced glutathione (GSH) in the retinas of the control and T1DM rats. In conclusion, MA prevents DR by antioxidant potential mediated by the activation of Nrf2.

Effect of Acacia senegal on TGF-ß1 and vascular mediators in a rat model of diabetic nephropathy.

CONTEXT: Transforming growth factor-ß1 (TGF-ß1), endothelin-1 and angiotensin II are responsible for extracellular matrix accumulation within the kidney in diabetic nephropathy. OBJECTIVE: This study evaluated the effect of adding Gum Arabic (GA) and insulin on serum glucose, renal function, TGF-ß1, endothelin-1, and angiotensin II in rats with diabetic nephropathy. METHODS: Sixty male Sprague-Dawley rats were divided into; normal, normal plus GA, diabetic rats (DM), DM plus insulin, DM plus GA, and DM plus insulin plus GA groups. Levels of glucose and creatinine in serum, TGF-ß1, angiotensin II, and endothelin-1 in renal homogenate and HbA1c were measured. RESULTS: Serum creatinine, TGF-ß1, angiotensin II, and endothelin-1 were increased in diabetic rats. GA decreased serum glucose, TGF-ß1, angiotensin II, endothelin-1, and HbA1c in diabetic rats. GA and insulin decreased serum glucose, creatinine, TGF-ß1, angiotensin II, endothelin-1, and HbA1c in diabetic rats. CONCLUSION: Co-administration of GA with insulin to rats with diabetic nephropathy improved the glycemic state, renal function, TGF-ß1, endothelin-1, and angiotensin II.

Modulatory Effect of Concomitant Administration of Insulin and Vanadium on Inflammatory Biomarkers in Type 2 Diabetic Rats: Role of Adiponectin.

The aim of this study is to investigate the effect of vanadium and/or insulin on the proinflammatory biomarkers in type 2 diabetes mellitus (T2DM) rat model. Sixty male Sprague Dawley rats were divided into six groups (n = 10). Control group, control vanadium group, T2DM group, insulin-treated diabetic group, vanadium-treated diabetic group, and concomitant insulin and vanadium-treated diabetic group. At the end of the experiment, serum glucose, insulin, lipid profile, tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), high sensitivity C reactive protein (hs- CRP), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and adiponectin were measured. Administration of insulin and/or vanadium significantly decreased in the plasma levels of glucose, lipid profile, TNF-α, IL-6, hs-CRP, ICAM-1, and VCAM-1 with significant increase in adiponectin in comparison to the diabetic group. Concomitant administration of insulin and vanadium significantly improved the above measured parameters compared to either insulin or vanadium treatment. Based on our results we can conclude that administration of both vanadium and insulin reduced the low-grade systemic inflammation in T2DM, through reduction of both proinflammatory cytokines and adhesion molecules and increase adiponectin.

Penile calcific uremic arteriolopathy occurring postparathyroidectomy in a hemodialysis patient.

Calcific uremic arteriolopathy (CUA), also known as calciphylaxis, is a rare condition most frequently seen in patients with advanced chronic kidney disease. The clinical picture is characterized by painful skin lesions and ulcerations. The underlying pathology is medial calcification and intimal proliferation with microthrombi of small arteries. CUA is commonly associated with secondary hyperparathyroidism and high serum calcium and phosphate products. This article reports an atypical case where CUA developed after parathyroidectomy and in the course of treatment of hungry bone syndrome. The patient was on hemodialysis for 14 years. He had developed secondary hyperparathyroidism and severe osteodystrophy. Calcium, Vitamin-D supplements, and calcimimetics failed to control his condition. He underwent parathyroidectomy but developed hungry bone syndrome postoperatively. He was managed with large doses of calcium and active Vitamin-D analogs to maintain his serum calcium. Two weeks later, he developed a painful single lesion on the tip of the penis which was diagnosed as CUA on clinical and radiographic evidence. The patient refused surgical intervention and opted for traditional treatment with honey and herbs with an excellent outcome. The case highlights the risk of CUA complicating the aggressive management of post-parathyroidectomy hungry bone syndrome.

Tolerance and efficacy of a low dose of the calcimimetic agent cinacalcet in controlling moderate to severe secondary hyperparathyroidism in hemodialysis patients.

Secondary hyperparathyroidism is almost a constant feature in chronic kidney disease (CKD) patients maintained on hemodialysis (HD). Calcimimetic agents appear to offer an alternative to surgery in controlling secondary hyperparathyroidism in these patients. Recent studies provide conflicting data on the benefits, efficacy and tolerance of cinacalcet as first-line therapy for the treatment of secondary hyperparathyroidism in CKD. This study was designed to investigate the efficacy and tolerance of a low dose of the calcimimetic agent cinacalcet in patients on long-term HD having moderate to severe secondary hyperparathyroidism. Twenty five adult male patients on HD for more than three years were included in the study. All had moderate to severe secondary hyperparathyroidism with serum intact parathyroid hormone (iPTH) >50 pmol/L, resistant to conventional treatment. We used the targets of Chronic Kidney Disease: Outcomes Quality Initiative (K/DOQI) clinical guidelines as optimal target of serum iPTH, calcium and phosphate. Patients were administered cinacalcet as a single oral daily dose of 30 mg and were followed-up for six months. Cinacalcet treatment for six months resulted in a significant reduction in the serum phosphate and iPTH levels while the serum calcium levels remained unchanged. Thirty-six percent of the patients attained the recommended serum iPTH levels, 40% achieved significant reduction of the serum iPTH levels and 24% showed no favorable response. Only one patient dropped out because of severe gastrointestinal symptoms. Our results suggest that treatment of CKD patients, having moderate to severe secondary hyperparathyroidism, with low-dose cinacalcet is effective and well tolerated.

Preventive roles of swimming exercise and pioglitazone treatment on hepatic dysfunction in a rat model of metabolic syndrome.

Pioglitazone (Pio) and swimming exercise (SE) are insulin sensitisers. This investigation was suggested because of the significant side effects associated with Pio treatment in metabolic syndrome (MetS). This study was, therefore, designed to investigate the preventive role of Pio treatment and SE in terms of efficiency and pathological changes in MetS in a rat model. Sixty male Sprague-Dawley rats were distributed equally among 6 groups: (i) control group (C), (ii) exercised control group (C+E), (iii) Pio-treated control group (C+Pio), (iv) group with MetS, (v) group with MetS treated with Pio (MetS+Pio), and (vi) exercised MetS group (MetS+E). Systolic blood pressure and heart rate were measured at the end of the experiments (16 weeks). Retro-orbital blood samples were used to determine the serum levels of glucose, insulin, lipids, gamma glutamyl transferase, alanine transaminase, aspartate transaminase, alkaline phosphatase, fetuin-A, and adiponectin. Semiquantitative reverse transcriptase - PCR insulin gene expression assays and hepatic histopathological examination were conducted. Swimming exercise significantly improved all of the aforementioned parameters, more so than the Pio treatment. In particular, the serum hepatic enzyme levels and hepatic histopathological changes were improved compared with the MetS group. These results suggested that swimming exercise might be an alternative physiological preventive tool against hepatic dysfunction to avoid the side effects associated with Pio treatment, and this could be demonstrated in a rat model of metabolic syndrome.

Alpha-tocopherol ameliorates oxidative renal insult associated with spinal cord reperfusion injury.

Ischemic-reperfusion procedures targeting a specific organ often results in remote multiple organ injuries mediated possibly by heightened oxidative stress levels. As the kidney is one of the most vulnerable organs for ischemic oxidative stress, the aim of the present study was to confirm the occurrence of renal complication secondary to spinal cord ischemic-reperfusion injury (SC-IRI) induced by aortic clamping. The study also investigated the possible prophylactic effect of long-term administration of α-tocopherol (α-TOL) against high level of renal oxidative stress and inflammatory processes induced by SC-IRI. In this study, a total of 60 male Sprague-Dawley rats were randomly divided into five equal groups: C group underwent no surgery; CE group received α-TOL 600 mg/kg intramuscular twice weekly for 6 weeks; S group were subjected to laparotomy without clamping of the aorta; SE group were handled as S group and treated with α-TOL as group CE; SC-IRI group were subjected to laparotomy with clamping of the aorta just above the bifurcation of the aorta for 45 min, then the clamp was released for 48 h for reperfusion. SC-IRIE group was subjected to IRI as in group SC-IRI and was injected with α-TOL in the same dose and route as α-TOL-treated control group. SC-IRI resulted in increases in serum creatinine, blood urea nitrogen, plasma nitrite/nitrate level, serum tumor necrosis factor alpha, renal tissue homogenate level for malondialdehyde, superoxide dismutase and prostaglandin E2. Long-term prophylactic treatment with α-TOL resulted in amelioration of the renal functional disturbances and all measured parameters of oxidative stress and inflammation. Ischemic reperfusion injury of the spinal cord induced some remote renal functional disturbances although some of the observed changes may have resulted from decreased renal blood flow due to the hypotension induced during the procedure. Prophylactic long-term α-TOL administration guards against the renal function disturbances an effect that can be attributed, at least partially, to improvement of the renal pro-oxidant/antioxidant balance and inhibition of the inflammatory processes.

Effect of vanadium on renal Na+,K+-ATPase activity in diabetic rats: a possible role of leptin.

Several researches attempt to protect diabetic patients from the development of nephropathy. Involvement of leptin and renal Na+,K+-ATPase enzyme in diabetic nephropathy (DN) development is a recent field for researches. Vanadium, as a trace element with insulin mimetic effect, may act synergistically with insulin to protect against the development of DN. Sixty male Sprague Dawley rats were divided into six groups: control group (C), vanadium control group (CV), streptozotocin-induced diabetic group (D), insulin-treated diabetic group (DI), vanadium-treated diabetic group (DV), and combined insulin and vanadium-treated diabetic group. Six weeks later, systolic blood pressure (SBP) was measured and retro-orbital blood samples were collected to estimate glycosylated hemoglobin (HbA(1c)), serum sodium (Na+) and creatinine, blood urea nitrogen (BUN) and plasma leptin levels. Preparation of microsomal fraction of renal tissue homogenate for estimation of Na+,K+-ATPase activity was done. The D group showed a significant increase in SBP, HbA(1c), serum Na+, creatinine, and BUN levels and Na+,K+-ATPase activity in microsomal fraction of renal tissue homogenate while plasma leptin level decreased significantly compared with C and CV groups. Both DI and DV groups showed a significant improvement in all the above measured parameters compared with D group while there were no significant changes between the DI and DV groups. Concomitant treatment with insulin and vanadium resulted in a significant improvement in all the measured parameters compared to each alone. Vanadium in combination with insulin ameliorates DN markers and reduces renal Na+,K+-ATPase overactivity in diabetic rats. An effect that may be partially mediated through correction of hypoleptinemia observed in these animals.

Effects of L-canavanine and ozone on vascular reactivity in septicemic rats.

Septicemia leads to oxidative stress with overproduction of reactive-oxygen species (ROS) and consumption of endogenous antioxidant enzymes. We tested a twofold hypothesis: (1) does oxidative stress (OxS) induced by sepsis acting alone or in concert with augmented inflammatory processes contributes to sepsis-related vascular dysfunction, and, (2) whether ozone (O(3)) and L-canavanine (CAV) mitigate the negative impact of the aforementioned phenomena. We investigated the relative impact of treatment with CAV and/or O(3) on vascular OxS associated vascular functional changes in septicemic rats. For this study, 60 male Sprague-Dawley rats were used and divided into six experimental groups (n = 10): control group (C), sham-operated (Sham), septicemic rats (S), S rats treated with CAV (100 mg/kg. i.p; S + CAV), S rats treated with O(3) (1.2 mg/kg, i.p.; S + O(3)) and S rats treated with both O(3) and CAV (S + O(3) + CAV). After 22 h, the mean arterial blood pressure (MAP), the aortic ring vascular reactivity to phenylephrine, abdominal aortic blood flow (AABF), serum tumor necrosis factor-alpha (TNF-alpha) and plasma nitrite/nitrate (NOx) concentration were measured. In addition, hepatic antioxidant enzyme activities sodium dismutase (SOD) and glutathione peroxidase (GSH-Px) were estimated. Septicemia caused significant elevation of serum TNF-alpha (p < 0.001) and plasma NOx (p < 0.001) and significant (p < 0.001) reduction of AABF (p < 0.001), aortic vascular response to phenylephrine (p < 0.001), MAP (p < 0.001) and hepatic SOD and GSH-Px activity (p < 0.001) compared with the C group, while treatment with O(3) and/or CAV induced significant amelioration of all those increases. Abnormalities were attenuated to a similar extent with treatment with both O(3) and CAV. These results suggested that concomitant administration of O(3) and CAV alleviated the compromised vascular reactivity in septicemic conditions and prevent its progression into septic shock compared with each alone.

A potential protective effect of alpha-tocopherol on vascular complication in spinal cord reperfusion injury in rats.

BACKGROUND: Paraplegia remains a potential complication of spinal cord ischemic reperfusion injury (IRI) in which oxidative stress induced cyclooxygenase activities may contribute to ischemic neuronal damage. Prolonged administration of vitamin E (alpha-TOL), as a potent biological antioxidant, may have a protective role in this oxidative inflammatory ischemic cascade to reduce the incidence of paraplegia. The present study was designed to evaluate the preventive value of alpha-TOL in IRI of spinal cord. METHODS: For this study, 50 male Sprague-Dawley rats were used and divided into five experimental groups (n = 10): Control group (C); alpha-TOL control group (CE) which received intramuscular (i.m.) alpha-TOL injections (600 mg/kg); Sham operated group (S), IRI rats were subjected to laparotomy and clamping of the aorta just above the bifurcation for 45 min, then the clamp was released for 48 hrs for reperfusion; and IRIE rats group, received 600 mg/kg of alpha-TOL i.m. twice weekly for 6 weeks, followed by induction of IRI similar to the IRI group. At the end of the experimental protocol; motor, sensory and placing/stepping reflex evaluation was done. Plasma nitrite/nitrate (NOx) was measured. Then animals' spinal cord lumbar segments were harvested and homogenized for measurement of the levels of prostaglandin E2 (PGE2), malondialdehyde (MDA) and advanced oxidation products (AOPP), while superoxide dismutase (SOD) and catalase (CAT) activity were evaluated. RESULTS: Induction of IRI in rats resulted in significant increases in plasma levels of nitrite/nitrate (p < 0.001) and spinal cord homogenate levels of PGE2, MDA, advanced oxidation protein products AOPP and SOD with significant reduction (p < 0.001) in CAT homogenate levels. Significant impairment of motor, sensory functions and placing/stepping reflex was observed with IRI induction in the spinal cord (p < 0.001). alpha-TOL administration in IRIE group significantly improved all the previously measured parameters compared with IRI group. CONCLUSIONS: alpha-TOL administration significantly prevents the damage caused by spinal cord IRI in rats with subsequent recovery of both motor and sensory functions. Alpha-tocopherol improves the oxidative stress level with subsequent reduction of the incidence of neurological deficits due to spinal cord IRI conditions.

Improvement of renal oxidative stress markers after ozone administration in diabetic nephropathy in rats.

BACKGROUND: Several complications of diabetes mellitus (DM) e.g. nephropathy (DN) have been linked to oxidative stress. Ozone, by means of oxidative preconditioning, may exert its protective effects on DN. AIM: The aim of the present work is to study the possible role of ozone therapy in ameliorating oxidative stress and inducing renal antioxidant defence in streptozotocin (STZ)-induced diabetic rats. METHODS: Six groups (n = 10) of male Sprague Dawley rats were used as follows: Group C: Control group. Group O: Ozone group, in which animals received ozone intraperitoneally (i.p.) (1.1 mg/kg). Group D: Diabetic group, in which DM was induced by single i.p. injections of streptozotocin (STZ). Group DI: Similar to group D but animals also received subcutaneous (SC) insulin (0.75 IU/100 gm BW.). Group DO: In which diabetic rats received the same dose of ozone, 48 h after induction of diabetes. Group DIO, in which diabetic rats received the same doses of insulin and ozone, respectively. All animals received daily treatment for six weeks. At the end of the study period (6 weeks), blood pressure, blood glycosylated hemoglobin (HbA1c), serum creatinine, blood urea nitrogen (BUN), kidney tissue levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxide (GPx), aldose reductase (AR) activities and malondialdehyde (MDA) concentration were measured. RESULTS: Induction of DM in rats significantly elevated blood pressure, HbA1c, BUN, creatinine and renal tissue levels of MDA and AR while significantly reducing SOD, CAT and GPx activities. Either Insulin or ozone therapy significantly reversed the effects of DM on all parameters; in combination (DIO group), they caused significant improvements in all parameters in comparison to each alone. CONCLUSIONS: Ozone administration in conjunction with insulin in DM rats reduces oxidative stress markers and improves renal antioxidant enzyme activity which highlights its potential uses in the regimen for treatment of diabetic patients.