Possible mechanisms for the renoprotective effects of date palm fruits and seeds extracts against renal ischemia/reperfusion injury in rats

PURPOSE

This work investigates the possible renoprotective effects of date palm fruits and seeds extract against renal ischemia and their underlying mechanisms.

METHODS

108-Sprague Dawle male rats were randomly allocated into 6 equal groups differently receiving aqueous or methanolic fruit and seed extracts. Assay of serum creatinine, BUN and TNF-α, morphological examination of the left kidney, markers of the redox state (MDA, CAT, and GSH), the expression of TNFα and Nrf2 genes at the level of mRNA, the expression of caspase-3 and TGF-β proteins by immunohistochemistry were performed.

RESULTS

45-min renal I/R caused significant deterioration of kidney functions (increase in serum creatinine and BUN) and morphology (P < 0.001) and significant reduction in CAT activity and GSH levels with significant increase in serum TNF-α and MDA concentration and the expression of Nrf2, caspase-3, TNF-α, and TGF-β in kidney tissues. Pre-treatment with either date palm fruit or seed extracts significantly improved kidney functions and morphology (P ≤ 0.001) with a significant increase in the expression of Nrf2 and CAT activity, and GSH concentration and a reduction in serum TNF-α and expression of caspase-3, TNF-α, and TGF-β (P < 0.001).

CONCLUSIONS

Administration of date palm extracts exhibited a renoprotective effect against renal I/R injury.This renoprotective action might be due to their antioxidants, anti-apoptotic and anti-inflammatory actions. Moreover, aqueous fruit extracts offered powerful renoprotective effect than aqueous seed extracts, and aqueous fruit and seed extracts were generally more effective than methanolic extracts.

Effects of Exercise and Ferulic Acid on Alpha Synuclein and Neuroprotective Heat Shock Protein 70 in An Experimental Model of Parkinsonism Disease

BACKGROUND & OBJECTIVE

This study investigated the effects of ferulic acid (FR), muscle exercise (Ex) and combination of them on rotenone (Rot)-induced Parkinson disease (PD) in mice as well as their underlying mechanisms.

METHOD

56 male C57BL/6 mice were allocated into 8 equal groups, 1) Normal control (CTL), 2) FR (mice received FR at 20 mg/kg/day), 3) Ex (mice received swimming Ex) and 4) Ex + FR (mice received FR and Ex), 5) Rot (mice received Rot 3 mg/Kg i.p. for 70 days), 6) ROT+ FR (mice received Rot + FR at 20 mg/kg/day), 7) ROT+ Ex (mice received Rot + swimming Ex) and 8) ROT+ Ex + FR (mice received Rot + FR and Ex). ROT group showed significant impairment in motor performance and significant reduction in tyrosine hydroxylase (TH) density and Hsp70 expression (p< 0.05) with Lewy bodies (alpha synuclein) aggregates in corpus striatum. Also, ROT+FR, ROT+EX and ROT + Ex+ FR groups showed significant improvement in behavioral and biochemical changes, however the effect of FR alone was more potent than Ex alone (p< 0.05) and addition of Ex to FR caused no more significant improvement than FR alone.

CONCLUSION

We concluded that, FR and Ex improved the motor performance in rotenone-induced PD rodent model which might be due to increased Hsp70 expression and TH density in corpus striatum and combination of both did not offer more protection than FR alone.

Effects of exercise and stevia on renal ischemia/reperfusion injury in rats

BACKGROUND

The present work was designed to study the effects of methanolic stevia extracts and aerobic exercise and combination of both on renal I/R injury in male rats.

METHODS

60 adult male Sprague-Dawley rats were subdivided into five equal groups as sham, control, exercise, stevia, and stevia plus exercise group. After 5 weeks of exercise and stevia, animals were exposed to 45 min of left renal ischemia and right nephrectomy followed by reperfusion. Serum creatinine, creatinine clearance, fractional Na excretion (FENa+), malondialdehyde (MDA), reduced glutathione (GSH) and catalase (CAT) levels in kidney tissues were measured. Also, renal histopathology and the expression of caspase-3 by immunohistochemical examination were done.

RESULTS

The results showed that stevia, exercise or combination of stevia and exercise caused a significant decrease in serum level of creatinine (p < 0.001) and FENa+ (p < 0.001) and an increase in creatinine clearance (p < 0.001). Moreover, this caused a significant decrease in (MDA; p < 0.046) and an increase in GSH (p < 0.01) and CAT (p < 0.01), as well as causing a significant decrease in caspase 3 expression compared to the control group.

CONCLUSIONS

Pretreatment with either stevia or exercise of combination of both seem to have protective effects on renal I/R injury. However, the protective effect of exercise against renal I/R injury seems to be less than stevia. These effects might be due to attenuation of oxidative stress and apoptosis in kidney tissues.

Combinatorial metabolism drives the naive to primed pluripotent chromatin landscape

Since epigenetic modifications are a key driver for cellular differentiation, the regulation of these modifications is tightly controlled. Interestingly, recent studies have revealed metabolic regulation for epigenetic modifications in pluripotent cells. As metabolic differences are prominent between naive (pre-implantation) and primed (post-implantation) pluripotent cells, the epigenetic changes regulated by metabolites has become an interesting topic of analysis. In this review we discuss how combinatorial metabolic activities drive the developmental progression through early pluripotent stages.

Melatonin Improves Memory Deficits in Rats with Cerebral Hypoperfusion, Possibly, Through Decreasing the Expression of Small-Conductance Ca2+-Activated K+ Channels

This study investigated the expression pattern, regulation of expression, and the role of hippocampal small-conductance Ca²⁺-activated K⁺ (SK) channels in memory deficits after cerebral hypoperfusion (CHP) with or without melatonin treatment, in rats. Adults male Wistar rats (n = 20/group) were divided into (1) a sham (2) a sham + melatonin (3) a two-vessel occlusion (2-VO) model, and (4) a 2-VO + melatonin. Melatonin was administered (i.p.) to all rats at a daily dose of 10 mg kg^-1 for 7 days starting at the time of 2-VO-induction. In contrast to 2-VO rats, melatonin increased the latency of the passive avoidance learning test and decreased time to find the hidden platform in Water Morris Test in all tested rats. In addition, it concomitantly downregulated SK1, SK2, and SK3 channels, downregulated mRNA levels of TNFα and IL-1β, enhanced BDNF levels and activity of PKA levels, and restored the levels of cholinergic markers in the hippocampi of the treated-rats. Mechanistically, melatonin significantly prevented CHP-induced activation of ERK1/2, JNK, and P38 MAPK at least by inhibiting ROS generation and enhancing the total antioxidant potential. In cultured hypoxic hippocampal neurons, individual blockage of MAPK signaling by the MEK1/2 inhibitor (U0126), but not by the P38 inhibitor (SB203580) or JNK inhibitor (SP600125), completely prevented the upregulation of all three kinds of SK channels. These data clearly confirm that upregulation of SK channels plays a role in CHP-induced memory loss and indicate that melatonin reverses memory deficits after CHP in rats, at least by, downregulation of SK1, SK2, and SK3 channels in their hippocampi.

Effects of heme oxygenase-1 upregulation on isoproterenol-induced myocardial infarction

The present study was designed to examine the effect of heme oxygenase-1 (HO-1) induction by cobalt protoporphyrin (CoPP) on the cardiac functions and morphology, electrocardiogram (ECG) changes, myocardial antioxidants (superoxide dismutase [SOD] and glutathione [GSH]), and expression of heat shock protein (Hsp) 70 and connexin 43 (Cx-43) in myocardial muscles in isoproterenol (ISO) induced myocardial infarction (MI). Thirty two adult male Sprague Dawely rats were divided into 4 groups (each 8 rats): normal control (NC) group, ISO group: received ISO at dose of 150 mg/kg body weight intraperitoneally (i.p.) for 2 successive days; ISO + Trizma group: received (ISO) and Trizma (solvent of CoPP) at dose of 5 mg/kg i.p. injection 2 days before injection of ISO, with ISO at day 0 and at day 2 after ISO injections; and ISO + CoPP group: received ISO and CoPP at a dose of 5 mg/kg dissolved in Trizma i.p. injection as Trizma. We found that, administration of ISO caused significant increase in heart rate, corrected QT interval, ST segment, cardiac enzymes (lactate dehydrogenase, creatine kinase-muscle/brain), cardiac HO-1, Hsp70 with significant attenuation in myocardial GSH, SOD, and Cx-43. On the other hand, administration of CoPP caused significant improvement in ECG parameters, cardiac enzymes, cardiac morphology; antioxidants induced by ISO with significant increase in HO-1, Cx-43, and Hsp70 expression in myocardium. In conclusions, we concluded that induction of HO-1 by CoPP ameliorates ISO-induced myocardial injury, which might be due to up-regulation of Hsp70 and gap junction protein (Cx-43).

Renoprotective effect of local sildenafil administration in renal ischaemia-reperfusion injury: A randomised controlled canine study

Objectives: To design a new canine model to assess the renoprotective effect of local sildenafil administration, as the renoprotective effect of systemic sildenafil administration in renal ischaemia-reperfusion (IR) injury in animal models has been shown but its local effects have not been established to date. Materials and methods: In all, 120 dogs were assigned to five groups: sham, oral control (OC) group (right nephrectomy + left renal ischaemia for 60 min), oral sildenafil (OS) group (oral sildenafil 1 mg/kg, 60 min before ischaemia), local control (LC) group (local renal perfusion with saline and heparin for 5 min) and local sildenafil (LS) group (perfusion with sildenafil 0.5 mg/kg). Renal functions, histopathological changes, expression of caspase-3, nuclear factor erythroid 2-related factor 2 (Nrf2), inflammatory cytokines (intracellular adhesion molecule 1, tumour necrosis factor α and interleukin 1β) and endothelial nitric oxide synthase (eNOS) in renal tissues were assessed in all groups at 1, 3, 7 and 14 days. Results: There were significant improvements in renal functions and cortical and medullary damage scores in the sildenafil-treated groups compared to their control groups (P < 0.05). Also, the LS group showed significantly better improvement of renal functions and cortical and medullary damage scores than the OS group (P < 0.05). Moreover, sildenafil significantly decreased the expression of caspase-3 and inflammatory cytokines and increased the expression of Nrf2 and eNOS in renal tissue, which were statistically significant in the LS group. Conclusion: LS has a greater renoprotective effect against renal IR injury than systemic administration via anti-inflammatory, antioxidant and anti-apoptotic pathways. Abbreviations: BUN: blood urea nitrogen; Ct: cycle threshold; eNOS: endothelial nitric oxide synthase; GAPDH: glyceraldehyde 3-phosphate dehydrogenase; H&E: haematoxylin and eosin; IL-1β: interleukin 1β; NO: nitric oxide; Nrf2: nuclear factor erythroid 2-related factor 2; OC: oral control; OS: oral sildenafil; LC: local control; LS: local sildenafil.

Effects of metformin on apoptosis and α-synuclein in a rat model of pentylenetetrazole-induced epilepsy

The present study was designed to examine the possible neuroprotective and antiepileptic effects of metformin (Metf) in a rat model of pentylenetetrazole (PTZ)-induced epilepsy and its possible underlying mechanisms. Forty male albino rats were assigned to 4 groups of equal size: (1) normal control (NC) group, (2) Metf group: daily treatment with Metf (200 mg/kg, i.p.) for 2 weeks, (3) PTZ group: treatment with PTZ (50 mg/kg, i.p.) every other day for 2 weeks, and (4) Metf + PTZ group: daily treatment with PTZ and metformin (200 mg/kg, i.p.) for 2 weeks. Administration of PTZ caused a significant increase in seizure score and duration, induced a state of oxidative stress (high malondialdehyde, low reduced glutathione and catalase activity), and led to the upregulation of β-catenin, caspase-3, and its cleavage products, Hsp70 and α-synuclein, in hippocampal regions as well as a significant reduction in seizure latency. While Metf treatment significantly ameliorated PTZ-induced seizures, attenuated oxidative stress, and upregulated α-synuclein and β-catenin expression, it also inhibited caspase-3 activation and the release of the cleavage product and caused more upregulation in Hsp70 expression in hippocampal regions (p < 0.05). In conclusion, the antiepileptic and neuroprotective effects of Metf in PTZ-induced epilepsy might be due to the inhibition of apoptosis, attenuation of oxidative stress and α-synuclein expression, and upregulation of Hsp70.

Effects of low dose of aliskiren on isoproterenol-induced acute myocardial infarction in rats

This study examined the effects of aliskiren (Ali) (direct renin inhibitor) on serum cardiac enzymes (LDH and CK-MB), electrocardiography (ECG) changes, myocardial oxidative stress markers (MDA, CAT, and GSH) and the expression of Bcl2, HO-1, and Nrf2 genes in isoproterenol (ISO)-induced myocardial infarction (MI). A total of 40 male albino rats were allocated into four groups, (1) normal control (NC) group, (2) Ali group (rats received Ali at 10 mg/kg/day p.o. for 5 days), (3) ISO group (rats received ISO 150 mg/kg i.p. for two consecutive days at 24 h intervals), and (4) Ali + ISO group (rats received ISO + Ali at 10 mg/kg/day p.o. for 5 days from the 2^nd dose of ISO). ISO group showed significant rise in serum cardiac enzymes (CK-MB and LDH), myocardial damage scores, myocardial MDA, HO-1, myocardial Nrf2 expression with significant reduction in myocardial antioxidants (CAT and GSH), and Bcl2 expression compared to the normal group (p < 0.05). ECG showed ST segment elevation, prolonged QT interval and QRS complex, and increased heart rate in ISO group. Co-administration of Ali and ISO caused significant increase in cardiac enzymes and morphology with increase in MDA, serum K, and creatinine with significant decrease in Bcl2, HO-1, and Nrf2 without significant changes in ECG parameters compared to ISO group. We concluded that low dose of Ali seems to exacerbate the myocardial injury in ISO-MI, which might be due to the enhanced oxidative stress and apoptosis.

Upregulation of heme oxygenase 1 (HO-1) attenuates kidney damage, oxidative stress and inflammatory reaction during renal ischemia/ reperfusion injury

The current study investigated the effect of upregulation of heme oxygenase 1 (HO-1) by cobalt protoporphyrin (CoPP) on renal dysfunctions in renal ischemia/reperfusion (I/R) injury and its underlying mechanisms. 72 male Sprague Dawley rats were divided into 4 groups: sham group, ischemic group (left 45-min renal ischemia), CoPP-before group (as ischemic group with CoPP 20 mg/kg 30 min before ischemia) and CoPP-after group (as ischemic group with CoPP 20 mg/kg 20 min after ischemia). Serum creatinine, urea and TGF-β1 and markers of redox state (MDA, SOD, GSH and CAT), nitric oxide (NO), TGF-β1 and HO-1 in kidney tissues were measured. Serum creatinine and urea levels were significantly increased in ischemic group and attenuated in CoPP-treated groups (p < 0.05). Also, markers of redox state showed significant deteriorations in ischemic group which were improved significantly in CoPP-treated groups (p < 0.05). HO-1 expression in kidney tissues showed significant increase in ischemic group and showed more significant increase in CoPP-treated groups (p < 0.05). Moreover, serum and renal TGF-β1 levels were significantly increased in ischemic group and attenuated in CoPP-treated groups (p ≶ 0.05). We concluded that up-regulation of HO-1 by CoPP treatment before and after renal I/R injury improved the kidney function and morphology and this might be due to impairment of oxidative stress and inflammatory cytokines in kidney tissues.

Possible mechanisms underlying fatty liver in a rat model of male hypogonadism: A protective role for testosterone

AIMS

To investigate the effects of testosterone (Test) deficiency and testosterone replacement therapy (TRT) on the development of non-alcoholic fatty liver disease (NAFLD) and associated peripheral insulin resistance (IR) in male rats and to illustrate the underlying mechanisms of action.

MATERIALS AND METHODS

male Sprague Dawley rats were divided into 3 groups as follows: 1) sham-operated group (n = 11), 2) ORCD-induced group (n = 9) exposed to orchidectomy (ORCD), achieved by complete surgical removal of testicles, and 3) ORCD + Test treated group (n = 10) (11 ng/mL Test propionate, 3x/week, S.C.).

RESULTS

Data revealed significant increases in final body, liver, visceral and subcutaneous fats weights with significant increases in fasting plasma glucose and insulin levels and HOMA-IR. Additionally, ORCD rats had higher UAC for measured glucose levels and insulin levels during OGTT and higher AUC for measured glucose levels during ITT. Interesting, higher serum and hepatic levels of TGs and CHOL and higher serum levels of LDL were seen in ORCD-induced rats. Mechanistically, significant increases in mRNA levels of SREBP-1, SREBP-2, ACC-1, FAS, HMGCOAR and HMGCOAS with significant increases in protein levels of both precursor and mature SREBP-1 and SREBP-2, PPAR-α, p-PPAR-α, CPT-1 and UCP-2 and significant lower protein levels p-AMPK and p-ACC-1 were detected in livers of ORCD rats. Test administration to ORCD-induced rats significantly ameliorated all of the above mentioned biochemical endpoints and reversed the effect of ORCD on mRNA and protein levels of these targets. In conclusion, Test deficiency could be an independent risk factor for the development of NAFLD by upregulation of lipid synthesis and disturb fatty acids oxidation whereas Test therapy is a protective strategy.

Attenuation of metabolic dysfunctions in the skeletal muscles of type 1 diabetic rats by Stevia rebaudiana extracts, via AMPK upregulation and antioxidant activities

BACKGROUND

Stevia rebaudiana Bertoni leaves are well-known for their sweetness and have been used as a non-caloric sweetener in several countries. It has numerous therapeutic properties which have been proven safe and effective over hundreds of years. In the present study, we aimed to evaluate the possible antioxidant effects of stevia extracts and their role in regulating AMPK in type-1 diabetic rats.

METHODS

Fifty male Sprague Dawely rats were divided into: (1) normal control (NC) group; normal rats receiving 0.5 ml normal saline, (2) DM group; diabetic rats receiving 0.5 ml normal saline, (3) DM + MSE group; DM rats receiving 200 mg/kg of methanolic extract of stevia, (4) DM + S group; DM rats receiving 2 mg/kg of pure stevioside, and (5) DM + CGA group; DM rats receiving 10 mg/kg of pure chlorogenic acid. Four weeks after treatment, AMPK activity, GLUT4 mRNA and oxidative stress markers were measured in frozen muscles. Also, fasting blood glucose in serum, insulin and HbA1c were measured at the end of experiment.

RESULTS

DM caused a significant increase in serum fasting glucose, HbA1c and muscle MDA with significant reduction in serum insulin, muscle SOD, catalase, GPx, AMPK activity and GLUT4 expression (p < 0.05). Treatment with stevia extract, pure stevioside and chlorogenic acid caused significant improvements in the studied parameters (p < 0.05).

CONCLUSIONS

We concluded that stevia extracts and derivatives may improve metabolic dysfunction in skel- etal muscles via upregulation of AMPK and GLUT4 and suppression of oxidative stress.

Morphometric parameters and histological study of the filum terminale of adult human cadavers and magnetic resonance images

BACKGROUND

Morphology and histology of filum terminale (FT) has a role in the pathophysiology of tethered cord syndrome (TCS). This research was implemented to investigate the morphometric parameters and histological structure of normal FT in adult human cadavers and magnetic resonance imaging (MRI) scans to correlate them with the pathophysiology of TCS.

MATERIALS AND METHODS

Twenty five adult human cadavers (15 males, 10 females) and 100 MRI echo scans of lumbosacral region (50 males and 50 females), were used in this study. MRI patients were divided into 21-40 and 41-60 age groups. The cadavers were dissected at the prone position to explore their fila. The length of FT, filum terminale internum (FTI), filum terminale externum (FTE), vertebral level of beginning, dural piercing and termination of FT, and the initial, midpoint, and mid-FTE diameters were determined. Four segments were excised from lower conus, upper, middle, and lower thirds of FT. The specimens were processed for light microscopic examination. Statistical analysis was done for these parameters.

RESULTS

MRI morphometrical parameters of FT, except FTI length, revealed no age effect or sex differences, where length of FTI, FTE, initial diameter, level of conus medullaris termination (CMT) and dural sac termination (DST) were 174.1 ± 16.8, 75.8 ± 9.5, 1.6 ± 0.21, L1-2 and S2U in males and 166.9 ± 18.9, 74.1 ± 9.3, 1.53 ± 0.25, L1-2 and S2M vertebrae in females, respectively. However, non-significant sex difference was observed in morphometric parameters of cadaveric FT, where length of FTI and FTE, initial diameter, CMT and DST levels were 164.2 ± 11.6, 76.7 ± 8.1, 1.7 ± 0.14, L1L and S2U vertebrae in males and 159.2 ± 10.1, 71.02 ± 7.3, 1.6 ± 0.29, L1L and S2U in females, respectively. Moreover, CMT below L2 vertebra was seen in 5% of MRI scans and 8% of cadavers. Also, the initial diameter of FT > 2 mm was recorded in 7% of MRI and 8% of cadaveric cases. Histologically, the structure of FT showed gradual reduction in nervous, glial, and vascular tissues with converse increase in collagen content in FTE compared with those of FTI.

CONCLUSIONS

Knowledge of the morphometric parameters and the histological structure of FT are necessary for clinicians who dealing with diagnosis or treatment of tethered cord syndrome.

l-Carnitine Modulates Epileptic Seizures in Pentylenetetrazole-Kindled Rats via Suppression of Apoptosis and Autophagy and Upregulation of Hsp70

l-Carnitine is a unique nutritional supplement for athletes that has been recently studied as a potential treatment for certain neuropsychiatric disorders. However, its efficacy in seizure control has not been investigated. Sprague Dawley rats were randomly assigned to receive either saline (Sal) (negative control) or pentylenetetrazole (PTZ) 40 mg/kg i.p. × 3 times/week × 3 weeks. The PTZ group was further subdivided into two groups, the first received oral l-carnitine (l-Car) (100 mg/kg/day × 4 weeks) (PTZ + l-Car), while the second group received saline (PTZ + Sal). Daily identification and quantification of seizure scores, time to the first seizure and the duration of seizures were performed in each animal. Molecular oxidative markers were examined in the animal brains. l-Car treatment was associated with marked reduction in seizure score (p = 0.0002) that was indicated as early as Day 2 of treatment and continued throughout treatment duration. Furthermore, l-Car significantly prolonged the time to the first seizure (p < 0.0001) and shortened seizure duration (p = 0.028). In addition, l-Car administration for four weeks attenuated PTZ-induced increase in the level of oxidative stress marker malondialdehyde (MDA) (p < 0.0001) and reduced the activity of catalase enzyme (p = 0.0006) and increased antioxidant GSH activity (p < 0.0001). Moreover, l-Car significantly reduced PTZ-induced elevation in protein expression of caspase-3 (p < 0.0001) and β-catenin (p < 0.0001). Overall, our results suggest a potential therapeutic role of l-Car in seizure control and call for testing these preclinical results in a proof of concept pilot clinical study.

Effects of ferulic acid on oxidative stress, heat shock protein 70, connexin 43, and monoamines in the hippocampus of pentylenetetrazole-kindled rats

The present study investigated the effects of ferulic acid (FA) on pentylenetetrazole (PTZ)-induced seizures, oxidative stress markers (malondialdehyde (MDA), catalase, and reduced glutathione (GSH)), connexin (Cx) 43, heat shock protein 70 (Hsp 70), and monoamines (serotonin (5-HT) and norepinephrine (NE)) levels in a rat model of PTZ-induced kindling. Sixty Sprague Dawley rats were divided into 5 equal groups: (a) normal group; (b) FA group: normal rats received FA at a dose of 40 mg/kg daily; (c) PTZ group: normal rats received PTZ at a dose of 50 mg/kg i.p. on alternate days for 15 days; (d) FA-before group: treatment was the same as for the PTZ group, except rats received FA; and (e) FA-after group: rats received FA from sixth dose of PTZ. PTZ caused a significant increase in MDA, Cx43, and Hsp70 along with a significant decrease in GSH, 5-HT, and NE levels and CAT activity in the hippocampus (p < 0.05). Pre- and post-treatment with FA caused significant improvement in behavioral parameters, MDA, CAT, GSH, 5-HT, NE, Cx43 expression, and Hsp70 expression in the hippocampal region (p < 0.05). We conclude that FA has neuroprotective effects in PTZ-induced epilepsy, which might be due to attenuation of oxidative stress and Cx43 expression and upregulation of neuroprotective Hsp70 and neurotransmitters (5-HT and NE).

Possible Underlying Mechanisms of the Renoprotective Effect of Remote Limb Ischemic Preconditioning Against Renal Ischemia/Reperfusion Injury: A Role of Osteopontin, Transforming Growth Factor-Beta and Survivin

BACKGROUND

It has been documented that remote limb ischemic preconditioning (rIPC) protect kidneys against renal ischemia/reperfusion (I/R). We hypothesized that osteopontin (OPN), transforming growth factor beta (TGF-β), apoptotic proteins (survivin and caspase-3) and oxidative stress play role in the renoprotective effects of rIPC.

MATERIALS AND METHODS

Fifty-four male Sprague-Dawley rats were randomized into 3 equal groups: sham group, I/R group (left renal 45 min ischemia) and rIPC group (as I/R group with 3 cycles of left hind limb ischemia just before renal ischemia). Each group was subdivided into 24, 48 and 72 h groups according to the time of sacrifice. We measured serum creatinine and blood urea nitrogen (BUN) at the baseline and end points. Also, left kidney was harvested at study end points for assessment of the expression of OPN, TGF-β, apoptotic proteins (survivin and caspase-3) and oxidative stress markers (malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD)) in kidney tissues and histopathological examination.

RESULTS

Serum creatinine and BUN levels and histopathological damage score were significantly lower in rIPC group than I/R group (p < 0.005). Also, compared to I/R group, the levels of MDA and the expression of OPN, TGF-β and caspase-3 in kidney tissues were significantly lower in rIPC group, while the levels of SOD and GSH and the expression of survivin in kidney tissues were significantly higher in rIPC group at all time points (p ≤ 0.05).

CONCLUSIONS

rIPC exhibited protective effects against renal I/R injury which might be due to inhibition of OPN expression, inflammatory cytokine TGF-β and caspase-3 and activation of anti-apoptotic protein survivin as well as improvement of oxidative stress in kidney tissues.

Beta Lactams Antibiotic Ceftriaxone Modulates Seizures, Oxidative Stress and Connexin 43 Expression in Hippocampus of Pentylenetetrazole Kindled Rats

Background and Purpose:

This study aimed to investigate the effect of ceftriaxone on oxidative stress and gap junction protein (connexin 43, Cx-43) expression in pentylenetetrazole (PTZ) induced kindling model.

Methods:

Twenty four Sprague dawely rats were divided into 3 equal groups (a) normal group: normal rats. (b) PTZ kindled group: received PTZ at the dose of 50 mg/kg via intraperitoneal injection (i.p.) every other day for 2 weeks (c) ceftriaxone treated group: received ceftriaxone at the dose 200 mg\kg/12 hrs via i.p. injection daily from the 6th dose of PTZ for 3 days. Racine score, latency before beginning the first myoclonic jerk and duration of the jerks used as parameters of behavioral assessment. Immunohistopathological study for Cx-43 expression in hippocampus and measurement of markers of oxidative stress (malondialdehyde [MDA], low reduced glutathione [GSH] and catalase [CAT]) in hippocampal neurons were done.

Results:

PTZ kindling was associated with behavioral changes (in the form high stage of Racine score, long seizure duration and short latency for the first jerk), enhanced oxidative stress state (as demonstrated by high MDA, low GSH and CAT) and up regulation of Cx43 in hippocampal regions. While, ceftriaxone treatment ameliorated, significantly, PTZ-induced convulsions and caused significant improvement in oxidative stress markers and Cx-43 expression in hippocamal regions (p < 0.05).

Conclusions:

These findings support the anticonvulsive effects of some beta-lactams antibiotics which could offer a possible contributor in the basic treatment of temporal lobe epilepsy. This effect might be due to reduction of oxidative stress and Cx43 expression.

Modulation of renal ischemia/reperfusion in rats by a combination of ischemic preconditioning and adipose-derived mesenchymal stem cells (ADMSCs)

The present study investigated the effects of combination of ischemic preconditioning (Ipre) and adipose-derived mesenchymal stem cells (ADMSCs) on renal ischemia-reperfusion (I-R) injury in rats. 90 male Sprague Dawley rats were divided into 5 equal groups; sham operated, control (45 min left renal ischemia), Ipre group as control group with 3 cycles of Ipre just before renal ischemia, ADMSCs-treated group (as control with ADMSCs 10(6) cells in 0.1 mL via penile vein 60 min before ischemia time), and Ipre + ADMSCs group as ADMCs group with 3 cycles of Ipre. Ipre and ADMSCs groups showed significant decrease in serum creatinine and blood urea nitrogen (BUN) and caspase-3 and CD45 expression in kidney and significant increase in HIF-1α, SDF-1α, CD31, and Ki67 expressions in kidney compared with the control group (p < 0.05). Moreover, the Ipre + ADMSCs group showed significant decrease in serum BUN and caspase-3 and CD45 expression in kidney with significant increase in HIF-1α, SDF-1α, CD31, and Ki67 expression in kidney compared with the Ipre and ADMCs groups (p < 0.05). We concluded that Ipre potentiates the renoprotective effect of ADMSCs against renal I/R injury probably by upregulation of HIF-1α, SDF-1α, CD31, and Ki67 and downregulation of caspase-3 and CD45.

Effects of aluminum oxide (Al2O3) nanoparticles on ECG, myocardial inflammatory cytokines, redox state, and connexin 43 and lipid profile in rats: possible cardioprotective effect of gallic acid

The objectives of present study were to examine the effects of aluminum oxide (Al2O3) nanoparticles on myocardial functions, electrical activities, morphology, inflammation, redox state, and myocardial expression of connexin 43 (Cx43) and the effect of gallic acid (GA) on these effects in a rat animal model. Forty male albino rats were divided into 4 equal groups: the control (normal) group; the Al2O3 group, rats received Al2O3 (30 mg·kg(-1), i.p.) daily for 14 days; the nano-alumina group, rats received nano-alumina (30 mg·kg(-1), i.p.) daily for 14 days; and the nano-alumina + GA group, rats received GA (100 mg·kg(-1) orally once daily) for 14 days before nano-alumina administration. The results showed disturbed ECG variables and significant increases in serum levels of LDH, creatine phosphokinase (CPK), CK-MB, triglycerides (TGs), cholesterol and LDL, nitric oxide (NO), and TNF-α and myocardial concentrations of NO, TNF-α, and malondialdehyde (MDA), with significant decreases in serum HDL and myocardial GSH, SOD, catalase (CAT), and Cx43 expression in the nano-alumina group. Pretreatment with GA improved significantly all parameters except serum and myocardial NO. We concluded that chronic administration of Al2O3 NPs caused myocardial dysfunctions, and pretreatment with GA ameliorates myocardial injury induced by nano-alumina, probably through its hypolipidaemic, anti-inflammatory, and antioxidant effects and upregulation of Cx43 in heart.

Renoprotective effects of aliskiren on adenine-induced tubulointerstitial nephropathy: possible underlying mechanisms

The present study investigated the possible renoprotective effect of direct renin inhibitor (aliskiren) on renal dysfunctions, as well as its underlying mechanisms in rat model of adenine-induced tubulointerstitial nephropathy. Forty male Sprague-Dawley rats were randomized into 4 groups; normal group, aliskiren group (normal rats received 10 mg/kg aliskiren), adenine group (animals received high-adenine diet for 4 weeks and saline for 12 weeks), and adenine + aliskiren group (animals received adenine for 4 weeks and aliskiren 10 mg/kg for 12 weeks). It was found that adenine caused significant decrease in body mass, Hb, HR, serum Ca(2+), eNOS and nrf2 expression, GSH, and catalase in kidney tissues with significant increase in arterial blood pressure (ABP), serum creatinine, BUN, plasma renin activity (PRA), K(+) and P, urinary albumin excretion (UAE), caspase-3, and MDA (lipid peroxidation marker) in kidney tissues compared to normal group (p < 0.05). Administration of aliskiren caused significant improvement in all studied parameters compared to adenine group (p < 0.05). We concluded that aliskiren has renoprotective effect against adenine-induced nephropathy. This might be due to inhibition of PRA, attenuation of oxidative stress, activation of Nrf2 and eNOS genes, and suppression of caspase-3.