Effect of aliskiren and carvedilol on expression of Ca(2+)/calmodulin-dependent protein kinase II δ-subunit isoforms in cardiac hypertrophy rat model.

CONTEXT: The critical role of CaMKIIδ isoforms in cardiac hypertrophy is well documented. OBJECTIVE: This study was aimed to investigate the possible inhibitory effects of aliskiren (ALS) and/or carvedilol (CAV) on CaMKIIδ isoforms expression in experimental cardiac hypertrophy. MATERIALS AND METHODS: Male Wistar albino rats were subcutaneously injected with isoproterenol (ISO) (5 mg/kg/day) for 4 weeks to induce cardiac hypertrophy. Hypertrophied rats were daily treated with either ALS (10 mg/kg) and/or CAV (10 mg/kg). At the end of the treatment, rats were killed; blood and hearts were collected for assessing different biochemical parameters. RESULTS: ISO treatment significantly increased heart weight to body weight (HW/BW) ratio, serum creatine kinase MB (CK-MB) and troponin T (Tn-T) levels, and plasma renin activity (PRA) as compared to control rats. Additionally, ISO treatment produced a significant increase in the expression of myocardial CaMKIIδ2 and CaMKIIδ3 that were associated with significant elevation in myocardial caspase-3 protein expression. Histopathological examination of rats exposed to ISO treatment showed severe myocardial cell degeneration. ALS and/or CAV treatment significantly reduced the altered HW/BW ratio, serum CK-MB and Tn-T levels, PRA, and caspase-3 protein expression in hypertrophied rats, with maximal improvement in the combination group. These biochemical findings were supported by the histopathological examination of the heart tissue. Additionally, treatment with ALS and CAV significantly inhibited ISO-induced increase in CaMKIIδ2 and CaMKIIδ3 expression levels. DISCUSSION AND CONCLUSION: The present study indicated that ALS and CAV treatment ameliorated ISO-induced hypertrophy via inhibiting the expression and the activity of CaMKIIδ isoforms and the associated myocardial apoptosis.

New mechanism in the modulation of carbon tetrachloride hepatotoxicity in rats using different natural antioxidants.

Transforming growth factor-ß (TGF-ß1) enhances the expression of apoptosis induced by certain cytokines and oncogenes. Activation of small mother against decapentaplegic (Smads) by TGF-ß results in fibrotic, apoptotic processes. PI-3/AKT focal adhesion kinase-phosphatidylinositol3-kinase (AKT), the mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription-3 (STAT3) pathways are influence in COX-2 and VEGF-stimulating pathways. NF-E2-related factor-2 (Nrf2) is an essential transcription factor that regulates an array of detoxifying and antioxidant defense genes expression in the liver. The objective of this study is to examine whether silymarin alone or in combination with vitamin E and/or curcumin plays a modulatory role against MAPK, STAT3, AKT, Smad-2 and TGF-ß protein expressions that produced apoptotic damage in rat's liver by the administration of carbon tetrachloride (CCl4). The results of the present work revealed that CCl4-induced an elevation of serum alanine aminotransferase (ALT) with concomitant increase in MAPK, STAT3, AKT, Smad-2 and TGF-ß hepatic protein expression, administration of silymarin alone down regulates these expressions. Treatment with vitamin E and/or curcumin along with silymarin produced best results in this concern. On the other hand, Nrf2 protein expression was down regulated by CCl4 whereas concurrent treatment with vitamin E and/or curcumin along with silymarin increased this expression. It was concluded that CCl4-induced protein expression of apoptotic and fibenorgenic factors. Whereas administration of silymarin alone or in combination with vitamin E and/or curcumin plays a modulatory role against the previous aforementioned apoptotic factors expressions. The use of vitamin E and/or curcumin potentiates the anti-apoptotic action of silymarin. So this combination can be used as hepatoprotective agent against other hepatotoxic substances.

Lactoferrin alleviates cyclophosphamide induced-nephropathy through suppressing the orchestration between Wnt4/ß-catenin and ERK1/2/NF-κB signaling and modulating klotho and Nrf2/HO-1 pathway.

AIMS: Cyclophosphamide is an alkylating agent with vast arrays of therapeutic activity. Currently, its medical use is limited due to its numerous adverse events, including nephrotoxicity. This study aimed to follow the molecular mechanisms behind the potential renoprotective action of lactoferrin (LF) against cyclophosphamide (CP)-induced renal injury. MATERIALS AND METHODS: For fulfillment of our aim, Spragw-Dwaly rats were orally administrated LF (300 mg/kg) for seven consecutive days, followed by a single intraperitoneal injection of CP (150 mg/kg). KEY FINDINGS: Treatment of CP-injured rats with LF significantly reduced the elevated creatinine and blood urea nitrogen (BUN), markedly upregulated Nrf2/HO-1 signaling with consequent increase in renal total antioxidant capacity (TAC) and decrease in renal malondialdehyde (MDA) level. Furthermore, LF treatment significantly reduced the elevated renal p-ERK1/2 expression, tumor necrosis factor-α (TNFα), interleukin-6 (IL-6), nuclear factor-kappa B (NF-κB) levels in CP-treated animals. Interestingly, LF treatment downregulated Wnt4/ß-catenin signaling and increased both renal klotho gene expression and serum klotho level. Furthermore, LF treatment reduced apoptosis in kidney tissue via suppressing GSK-3ß expression and modulating caspase-3 and Bcl2 levels. Histopathological examination of kidney tissue confirmed the protective effect of LF against CP-induced renal injury. SIGNIFICANCE: The present findings document the renoprotective effect of LF against CP-induced nephropathy, which may be mediated via suppressing ERK1/2/ NF-κB and Wnt4/ß-catenin trajectories and enhancing klotho expression and Nrf2/HO-1 signaling.

Role of quercetin and arginine in ameliorating nano zinc oxide-induced nephrotoxicity in rats.

BACKGROUND: Nanoparticles are small-scale substances (<100 nm) with unique properties. Therefore, nanoparticles pose complex health risk implications. The objective of this study was to detect whether treatment with quercetin (Qur) and/or arginine (Arg) ameliorated nephrotoxicity induced by two different doses of nano zinc oxide (n-ZnO) particles. METHOD: ZnO nanoparticles were administered orally in two doses (either 600 mg or 1 g/Kg body weight/day for 5 conscutive days) to Wister albino rats. In order to detect the protective effects of the studied antioxidants against n-ZnO induced nepherotoxicity, different biochemical parameters were investigated. Moreover, histopathological examination of kidney tissue was performed. RESULTS: Nano zinc oxide-induced nephrotoxicity was confirmed by the elevation in serum inflammatory markers including: tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6); and C-reactive protein (CRP). Moreover, immunoglobulin (IGg), vascular endothelium growth factor (VEGF), and nitric oxide (NO) were significantly increased in rat serum. Serum urea and creatinine levels were also significantly increased in rats intoxicated with n-ZnO particles compared with the control group. Additionally, a significant decrease in the non-enzymatic antioxidant reduced glutathione (GSH) was shown in kidney tissues and serum glucose levels were increased. These biochemical findings were supported by a histopathological examination of kidney tissues, which showed that in the animals that received a high dose of n-ZnO, numerous kidney glomeruli underwent atrophy and fragmentation. Moreover, the renal tubules showed epithelial desquamation, degeneration and necrosis. Some renal tubules showed casts in their lumina. Severe congestion was also observed in renal interstitium. These effects were dose dependent. Cotreatment of rats with Qur and/or Arg along with n-ZnO significantly improved most of the deviated tested parameters. CONCLUSIONS: The data show that Qur has a beneficial effect against n-ZnO oxidative stress and related vascular complications. Also, its combination with Arg proved to be even more effective in ameliorating nano zinc oxide nephrotoxicity.

Diacerein attenuate LPS-induced acute lung injury via inhibiting ER stress and apoptosis: Impact on the crosstalk between SphK1/S1P, TLR4/NFκB/STAT3, and NLRP3/IL-1ß signaling pathways.

AIMS: Acute lung injury (ALI) is a life-threatening clinical problem with high mortality rate and limited treatments or preventive options that represents a major challenge for clinicians. Diacerein (DIA) is a multi-target anthraquinone derivative with potent anti-inflammatory action. The aim of this study is to assess the protective effect of DIA and its potential molecular targets against lipopolysaccharide (LPS)-induced ALI in rats. MATERIALS AND METHODS: Adult male Sprague-Dawley rats were orally administrated DIA (50 mg/kg) for 5 consecutive days followed by a single intraperitoneal injection of LPS (5mg/kg). KEY FINDINGS: DIA mitigated oxidative lung injury in LPS-challenged rats via significantly decreasing lung wet/dry (W/D) ratio, inflammatory cells infiltration, and lipid peroxidation, with concomitant elevation in enzymatic and non-enzymatic antioxidant levels in lung tissue. Likewise, DIA alleviated endoplasmic reticulum stress and markedly halted inflammation triggered by LPS challenge in pulmonary tissue by suppressing NLRP3/IL-1ß and TLR4/NF-κB signaling with parallel decrease in proinflammatory cytokine levels. Interestingly, DIA down regulated Sphk1/S1P axis, reduced GSK-3ß and STAT3 proteins expression, and markedly decreased caspase-3 besides increasing Bcl-2 levels in lung tissue of LPS-challenged animals. These biochemical findings was simultaneously associated with marked improvement in histological alterations of lung tissue. SIGNIFICANCE: These findings verify the protective effect of DIA against LPS-induced ALI through targeting oxidative stress, endoplasmic reticulum stress, and apoptosis. Importantly, DIA halted the hyperinflammatory state triggered by LPS via multi-faceted inhibitory effect on different signaling pathways, hence DIA could potentially reduce mortality in patients with ALI.

Pramipexole and Lactoferrin ameliorate Cyclophosphamide-Induced haemorrhagic cystitis via targeting Sphk1/S1P/MAPK, TLR-4/NF-κB, and NLRP3/caspase-1/IL-1ß signalling pathways and modulating the Nrf2/HO-1 pathway.

BACKGROUND: The use of cyclophosphamide (CP) as a chemotherapeutic agent is limited by its major complication haemorrhagic cystitis (HC). Finding preventive, safe, and efficient treatments for such problems is extensively ongoing. OBJECTIVE: This research aims to assess the uroprotective effect of pramipexole (PPX) and/or lactoferrin (LF) against CP-induced HC, in addition to shedding light on their possible molecular targets. METHODS: Adult male Sprague-Dawley rats were orally administered PPX (3 mg/kg) and/or LF (300 mg/kg) for seven consecutive days, followed by a single intraperitoneal injection of CP (150 mg/kg). RESULTS: Pretreatment of CP-intoxicated rats with either PPX or LF mitigated oxidative urinary bladder damage via upregulation of the Nrf2/HO-1 signalling pathway, resulting in a significant reduction in bladder MDA and 8-OHdG levels with concomitant elevations in SOD activity and GSH content. Simultaneously, both drugs markedly halted inflammation in bladder tissue through inhibition of the TLR4/NF-κB signalling pathway, followed by a significant decrease in inflammatory cytokine levels (TNF-α and IL-6). Interestingly, the PPX/LF protocol downregulated p-p38, p-ERK1/2, Sphk1, and S1P protein expression and inhibited the NLRP3/caspase1/IL-1ß axis. PPX/LF also significantly reduced BAX and caspase-3, in addition to increasing Bcl-2 levels in bladder tissue of CP-treated animals. These biochemical findings were supported by the improvement in the histological alterations induced by CP in the urinary bladder. CONCLUSIONS: The current study verified the protective effect of PPX and LF against CP-induced HC by halting oxidative stress, inflammation, and apoptosis. The molecular mechanism underlying this protective effect may involve targeting the crosstalk among Sphk1/S1P/MAPK/NF-κB, TLR-4/NF-κB, and NLRP3/caspase-1/IL-1ß signalling pathways and modulating the Nrf2/HO-1 signalling pathway.

Cardioprotective effect of pioglitazone and curcumin against diabetic cardiomyopathy in type 1 diabetes mellitus: impact on CaMKII/NF-κB/TGF-ß1 and PPAR-γ signaling pathway.

Diabetic cardiomyopathy (DCM) is a leading cause of death in diabetic patients, which is currently without available specific treatment. This study aimed to investigate the potential protective effects of pioglitazone (Pio) and curcumin (Cur) against DCM in type 1 diabetes mellitus (T1DM), with pointing to their role on Ca+2/calmodulin-dependent protein kinase II (CaMKII) and peroxisome proliferator-activated receptor gamma (PPAR-γ) expression. Diabetes was induced in adult male Sprague Dawley rats by administration of single intraperitoneal injection of streptozotocin (STZ) (52.5 mg/kg). Diabetic rats were administered either Pio (20 mg/kg/day) or Cur (100 mg/kg/day) orally for 6 weeks. Treatment with Pio and/or Cur markedly reduced serum cardiac injury markers and lipid profile markers in diabetic animals. Additionally, Pio and/or Cur treatment mitigated oxidative stress and fibrosis in diabetic rats as evident from the significant suppression in myocardial lipid peroxidation and tumor growth factor beta 1 (TGF-ß1) level, with concomitant significant elevation in total antioxidant capacity (TAC) and improvement in histopathological architecture of heart tissue. Pio/Cur treatment protocol accomplished its cardioprotective effect by depressing cardiac CaMKII/NF-κB signaling accompanied by enhancement in PPAR-γ expression. Conclusively, these findings demonstrated the therapeutic potential of Pio/Cur regimen in alleviating DCM in T1DM through modulation of CaMKII and PPAR-γ expression. Graphical Abstract.

Curcumin augments the cardioprotective effect of metformin in an experimental model of type I diabetes mellitus; Impact of Nrf2/HO-1 and JAK/STAT pathways.

Metformin is one of the most commonly prescribed antidiabetic drugs. A recent clinical study has highlighted the protective role of metformin against cardiac complications in type I diabetes. Curcumin is a natural compound with well-known antioxidant and anti-inflammatory properties. The present study was designed to investigate the possible role of curcumin in potentiating metformin`s putative effects. Rats received single injection of 52.5 mg/kg streptozocin and the diabetic rats were treated with metformin (200 mg/kg/day), curcumin (100 mg/kg/day) and their combination for 6 weeks. Diabetic rats showed degenerated myocardium as well as significant increase in Creatine Kinase-MB (CK-MB), troponin I and TGF-ß1 levels. In addition, cardiac levels of lipid peroxidation, IL-6, and NF-κB were significantly elevated. Although treatment with metformin restored most of the measured parameters, it showed insignificant improvement in histopathological architecture accompanied by absence of antioxidant effect. Interestingly, concomitant administration of curcumin along with metformin revealed more protection than metformin alone. Inhibition of JAK/STAT pathway and activation of Nrf2/HO-1 pathway seems to be among the mechanisms mediating the effects of curcumin and metformin. The findings of this study highlight the benefits of metformin/curcumin combination in preventing diabetic cardiomyopathy.

Lisinopril has a cardio-protective effect on experimental acute autoimmune myocarditis in rats.

PURPOSE: The present study investigated the effect of lisinopril on experimental autoimmune myocarditis (EAM) in rats, a histologically similar model to human acute myocarditis. ANIMALS AND METHODS: Twenty four, six week-old male Wistar rats were randomly allocated into 4 groups of 6 rats each. Group I received no treatment. Group II received lisinopril at a dose of 15 mg/kg/day suspended in 1 ml of 2% gum acacia daily, from day 1 to day 21. To induce myocarditis, animals of groups III and IV were injected by 1 mg of porcine cardiac myosin on days 1 and 8. In addition, animals of group IV received lisinopril in gum acacia daily, from day 1 to day 21. All rats were sacrificed on day 21. Serum levels of creatine phosphokinase, troponin-T, tumor necrosis factor-α and interleukin-6 were estimated. Hearts were processed for histopathological, as well as immunohistochemical study for thioredoxin (TRX) immunoreactivity. RESULTS: The wall of hearts from rats of myocarditis-lisinopril group showed mild focal myocarditis and a significant decrease of the mean percentage of pyknotic nuclei in cardiomyocytes, coincident with a significant decrease in serum biomarkers levels and TRX immunoreactivity, compared to myocarditis group. CONCLUSION: The present study suggested a cardio-protective effect of lisinopril on acute EAM in rats, probably through a mechanism related to its suppressive effect on angiotensin II formation.

Potential impact of quercetin and idebenone against immuno- inflammatory and oxidative renal damage induced in rats by titanium dioxide nanoparticles toxicity.

The aim of this study was to investigate the toxic impacts of titanium dioxide nanoparticles (TiO2-NPs) on rat kidneys and the possible prophylactic role of either quercetin or idebenone. TiO2-NPs were administered orally at either 600 mg or 1 g/kg body weight for 5 consecutive days to evaluate dose-dependent toxicity referred to the OECD guidelines for testing of chemicals. The results showed that administration of either low or high repeated doses of TiO2-NPs to rats significantly increases serum kideney function biomarkers (urea, creatinine and uric acid) as well as increases in serum glucose and serum immuno- inflammatory biomarkers including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), immunoglobin g (IGg), vascular endothelial growth factor (VEGF, angiogenic factor) and nitric oxide (NO) with a concomitant decrease in renal GSH content versus normal control values. The increase in these biomarkers was more evident in rats intoxicated with high TiO2-NPs repeated doses. Oral co- administration of either quercetin or idebenone (each 200mg/Kg body weight) daily for three weeks to rats intoxicated by either of the two doses markedly ameliorated TiO2-NPs induced alteration in the above biomarkers. The prophylactic impacts of both agents on biochemical markers were more pronounced in rats received low TiO2-NPs repeated doses. The biochemical investigation was supported by histological examination. In conclusion, The data showed the severity in renotoxicity of TiO2-NPs was dose-dependent and the protective effect of quercetin and idebenone may be related to their antioxidant and anti-inflammatory properties.

Nitric oxide pros and cons: The role of L-arginine, a nitric oxide precursor, and idebenone, a coenzyme-Q analogue in ameliorating cerebral hypoxia in rat.

Evidence exists that nitric oxide (NO) may mediate both protective and pathological responses during brain hypoxia (HP). Reactive oxygen species have also been implicated in the pathophysiological response of the brain tissues to HP. Therefore, this study investigated whether a NO precursor, l-arginine (l-arg), a free radical scavenger, idebenone (ID), and their combination would reduce neurological injury resulting from hemic hypoxia (HP) in rats. Adult male Wistar albino rats were injected with sodium nitrite (60 mg/kg, s.c.) to establish hemic hypoxia. ID (100 mg kg(-1), i.p.) and/or l-arg (100 mg kg(-1), i.p.) were administrated 24 and 1h prior to sodium nitrite intoxication, respectively. Hypoxia significantly decreased hemoglobin concentration, while significantly increased serum lactate dehydrogenase (LDH), creatine phosphokinase (CPK), total nitrate/nitrite, sialic, and uric acids concentrations. Moreover, brain lipid peroxides were significantly enhanced, while reduced glutathione, l-ascorbic acids, adenosine triphosphate (ATP) contents, and the activities of catalase and superoxide dismutase, were significantly reduced in the brain tissue. Pretreatment with either ID or l-arg altered the majority of the above-mentioned biochemical changes in hypoxic rats. Additionally, the combination of these two agents significantly reduced injury marker enzyme activities as well as serum sialic, and uric acids level (P>0.05 vs. control). Moreover, this combination exerted a synergistic antioxidant effect by blocking the induction of lipid peroxidation, preserving brain energy (ATP) content, and greatly reducing the hypoxic alterations in brain enzymatic and non-enzymatic antioxidants. Histopathological examination of the brain tissue supported these biochemical findings. This study showed that ID and l-arg were capable of reducing neurological injury following HP in rat, and support the idea of the usefulness of l-arg and ID as prophylaxis from hypoxic brain injury.