TLR4/ MyD88/NF-κB signaling pathway involved in the protective effect of diacerein against lung fibrosis in rats.

PURPOSE: Pulmonary fibrosis (PF) is an inescapable problem. Diacerein, a chondro-protective drug, has antioxidant and anti-inflammatory effects. Its effect on PF injury has not yet been fully clarified. Therefore, the current study aimed to detect its protective effect on lung tissue with the explanation of possible underlying mechanisms. METHODS: Adult male albino rats were assigned to four groups: control group, diacerein control group, PF non-treated group, and PF diacerein pretreated group. Lung tissue oxidative stress parameters, inflammatory biomarkers mainly Toll-like receptors-4 (TLR4), and myeloid differentiation factor 88 (MyD88) levels were determined. Histopathological examination of lung tissue and immunohistochemical studies of nuclear factor-kappa B (NF-κB), and transforming growth factor- ß (TGF-ß) were also done. RESULTS: Diacerein pretreatment has the ability to restore the PF damaging effect, proved by the reduction of the oxidative stress and lung tissue inflammation via downregulation of TLR4/NF-κB signaling pathway together with the restoration of TGF-ß level and improvement of the histopathological and immunohistochemical study findings in the lung tissue. CONCLUSION: These results suggested the protective effect of diacerein on PF relies on its antioxidant and anti-inflammatory effects reducing TLR4/NF-κB signaling pathway.

Empagliflozin Protects against Haloperidol Experimentally-Induced Ovarian Toxicity.

The present experiment aimed to identify the potential protective role of empagliflozin (EMPA) on haloperidol (HAL)-induced ovarian damage in female rats because of its anti-inflammatory, antioxidant, and antiapoptotic effects. EMPA was administered in the presence and absence of HAL. Thirty-two adult female albino rats were divided into four groups. Control group, EMPA group: received EMPA (10 mg/kg/day) p.o., HAL group: received HAL (2 mg/kg/day) p.o., HAL + EMPA group: HAL (2 mg/kg/day) combined with EMPA for 28 days. Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), and anti-mullerian hormone (AMH) levels were measured. Ovarian oxidative stress parameters, besides inflammatory and apoptotic biomarkers, and ovarian Sirtuin-1 (Sirt-1) were evaluated. Ovarian histopathological examination and heat shock protein 70 (Hsp70) immunohistochemical study were performed. HAL significantly increased serum levels of FSH, LH, and ovarian inflammatory, apoptotic, and oxidative stress biomarkers and decreased serum AMH levels and Sirt-1 expression. Histopathological findings of ovarian damage and high Hsp70 immunoexpression were detected. EMPA significantly normalized the distributed hormonal levels, oxidative stress, inflammatory, and apoptotic biomarkers with a prompt improvement in the histopathological picture and a decrease in Hsp70 immunoexpression. Accordingly, EMPA protected against HAL-induced ovarian toxicity by modulating the Sirt-1/Hsp70/TNF-α/caspase-3 signaling pathway.

Potential role of carvedilol in intestinal toxicity through NF-κB/iNOS/COX-2/TNF-α inflammatory signaling pathway in rats.

BACKGROUND: The increased use of indomethacin (IND) is associated with gastrointestinal injury. This research aims to investigate the effects of a beta-blocker, carvedilol (CAR) on a rat model of IND-induced acute intestinal damage and clarify the probable underlying protective mechanisms. MATERIALS AND METHODS: Twenty-four male Wistar rats were divided into four groups. Control group: given vehicles; CAR-treated group: given 10 mg/kg/day CAR PO daily by gastric gavage for 10 consecutive days; IND-treated group: given a single Sc dose of 10 mg/kg IND at the end of the ninth day of the experiment; combined CAR/IND-treated group: given both IND and CAR. RESULTS: In the rats that received IND, severe intestinal histopathological changes together with oxidative and nitrosative intestinal stress were present biochemically and immunohistochemically. Obvious inflammatory and tissue damage were represented by the significant intestinal increases in TNF-α, COX-2, and caspase-3 together with the elevated expression of VCAM-1 adhesion molecules. Intestinal gene expression of NF-kB and COX-2 was also increased. Pretreatment with CAR significantly reversed the IND-induced intestinal toxic manifestations. CONCLUSION: CAR has beneficial intestinal protective effects. Its ameliorative action is conferred through its antioxidant, antinitrosative, anti-inflammatory, and antiapoptotic properties.

Diacerein ameliorates letrozole-induced polycystic ovarian syndrome in rats.

Polycystic ovary syndrome (PCOS) is the most common gynaecological endocrine disease that causes anovulatory infertility. The current study aimed to explore the possible role of diacerein (DIA), an IL-1ß inhibitor, in treating letrozole-induced PCOS in rats that exhibit the metabolic and endocrinal criteria of PCOS patients. PCOS was induced in female Wistar rats by the oral administration of letrozole (1 mg/kg, per orally, p.o.) for 21 days. Rats were then treated with DIA (25 mg/kg/day, p.o.), DIA (50 mg/kg/day, p.o.), or metformin (2 mg/100 g/day, p.o.) for 14 days after the PCOS induction. PCOS resulted in a significantly higher body weight, ovarian weight, ovarian size, and cysts, as well as an elevation in serum testosterone, LH, insulin, glycemia, and lipid profile levels. All of these effects were significantly reduced by the DIA administration. Additionally, DIA remarkably inhibited the letrozole-induced oxidative stress in the ovaries, muscles, and liver by reducing the upraised levels of malondialdehyde and total nitrite and increasing the suppressed levels of superoxide dismutase and catalase. DIA enhanced the protective proteins Keap-1, Nrf2, and OH-1 levels. Finally, DIA inhibited the elevated mRNA levels of NLRP3 and caspase-1, the up-regulated inflammatory cytokines IL-6, TNF-α, and the IL-1ß/NFκB signaling pathway. Our results proved that DIA ameliorates letrozole-induced PCOS through its antioxidant and anti-inflammatory properties.

Role of IL-6/STAT3 pathway in mediating the protective effect of agomelatine against methotrexate-induced lung/intestinal tissues damage in rats.

BACKGROUND: Methotrexate (MTX), an anticancer drug, has been linked to multiple organ toxicity. The drug-induced acute toxic symptoms can negatively affect the patient's commitment to the course of treatment. MATERIALS AND METHODS: This study aimed to investigate the mitigating action of agomelatine (Ago) against MTX-induced lung and intestinal toxicity. Forty eight male Wister rats were randomized into six experimental groups: Group 1: Control; Groups 2 and 3: received Ago L&H (20/40 mg/kg, respectively by gavage); Group 4: received MTX 10 mg/kg/day, i.p. on days 7-9; Group 5: received Ago L (20 mg/kg) + MTX; Group 6: received Ago H (40 mg/kg) +MTX. The duration of the study was 10 days. Lung/intestine oxidative markers were measured. Lung/intestinal tissues IL-6, STAT3, and HO-1 levels were evaluated by ELISA. Besides, lung/intestinal tissues were examined for Histological changes, collagen fibers detection using Massonꞌs trichome stain, and immunohistochemical study using HSP70 antibody. RESULTS: MDA, NOx, IL-6, and STAT3 levels were significantly higher in the MTX group's lungs and intestines, indicating lung and intestinal toxicity. There were substantial decreases in GSH, SOD tissue levels, and HSP 70 immunoexpression, as well as histological changes suggesting significant lung and intestinal injury. All of the above parameters improved significantly by using Ago. CONCLUSION: By reducing oxidative stress, inflammatory processes, and modulating the IL-6/STAT3 pathway, Ago has potent ameliorative effects against MTX-induced lung/intestinal toxicities.

Rivaroxaban Modulates TLR4/Myd88/NF-Kß Signaling Pathway in a Dose-Dependent Manner With Suppression of Oxidative Stress and Inflammation in an Experimental Model of Depression.

Depression is a common mental illness leading to upset or anxiety, with a high incidence rate in the world. Depression can lead to suicidal thoughts and behavior. The present study aimed to evaluate the effect of the direct oral anticoagulant rivaroxaban (RVX), in the model of depression induced by chronic unpredicted mild stress (CUMS) in rats. Fifty-six male Wister rats were randomly divided into seven experimental groups (8 rats/group); Group 1: Control group given vehicle per oral (p.o.), Group 2: RVXL-control group (received rivaroxaban 20 mg/kg/day, p.o..), Group 3: RVXH-control group (received rivaroxaban 30 mg/kg/day, p.o.), Group 4: chronic unpredictable mild stress (CUMS) group, Group 5: FLX-treated CUMS group (received fluoxetine 10 mg/kg/day, p.o..), Group 6: RVXL-treated CUMS group (received rivaroxaban 20 mg/kg/day, p.o.), and Group 7: RVXH-treated CUMS group (received rivaroxaban 30 mg/kg/day, p.o.). The rats received the drugs from the first day of the experiment and continued till 4 weeks-the duration of the study. The following were measured: monoamine neurotransmitters, malondialdehyde (MDA), total nitrite/nitrate (NOx), reduced glutathione (GSH), superoxide dismutase (SOD), Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), brain-derived neurotrophic factor (BDNF), and vascular endothelial growth factor-A (VEGF-A). A forced swimming test (FST) was done. Furthermore, histological changes and glial fibrillary acidic protein (GFAP) immunoexpression were evaluated. CUMS showed a significant decrease in hypothalamic neurotransmitters, hippocampal GSH, SOD, BNDF, and VEGF-A with a significant increase in hippocampal MDA, NOx, NF-kß, Myd88, TLR4, TNF-α, and GFAP immunoexpression. RVX showed significant improvement in all parameters (p -value < 0.0001). In conclusion, RVX in a dose-dependent manner possesses potent ameliorative effects against depression by reducing the oxidative stress and inflammatory process, through the regulation of the TLR4/Myd88/NF-kß signaling pathway.

Diacerein protects rats with liver ischemia/reperfusion damage: Down-regulation of TLR4/ NFκ-B signaling pathway.

PURPOSE: Liver ischemia-reperfusion (I/R) injury is an inescapable problem. Diacerein, a chondro-protective drug, has antioxidant and anti-inflammatory effects. Its effect on liver I/R injury has not yet been fully clarified. Therefore, the current study aimed to detect its hepatic protective effect with the explanation of possible underlying mechanisms. METHODS: Adult male albino rats were assigned to 4 groups: sham group, diacerein pretreated sham group, I/R non-treated group, and I/R diacerein pretreated group. Serum liver enzymes, hepatic tissue oxidative stress parameters, inflammatory biomarkers mainly Toll-like receptors-4 (TLR4), and liver fatty acid binding protein (L-FABP) levels were determined. Histopathological examination of liver tissues and immunohistochemical studies of heat shock protein 70, nuclear factor-kappa B, and Cluster of Differentiation 68 were also done. RESULTS: Diacerein pretreatment has the ability to restore the hepatic I/R damaging effect, proved by the reduction of serum liver enzymes, the decrease of the oxidative stress and hepatic inflammation via down-regulation of TLR4/ NFκ-B signaling pathway together with the restoration of L-FABP level and improvement of the histopathological and immunohistochemical study findings in the hepatic tissue. CONCLUSION: These results suggested the hepatoprotective effect of diacerein relies on its antioxidant and anti-inflammatory effects reducing TLR4/ NFκ-B signaling pathway.

Amelioration of testosterone-induced benign prostatic hyperplasia using febuxostat in rats: The role of VEGF/TGFß and iNOS/COX-2.

Benign prostatic hyperplasia (BPH) is a common male disorder. Febuxostat is a non-purine, selective inhibitor of xanthine oxidase (XO), which has a strong antioxidant capacity and pleiotropic pharmacological properties. This study's objective was to explore the potential ameliorative effects of febuxostat against testosterone-induced BPH in rats. Febuxostat (10 mg/kg/day, per os [p.o.]) prevented increased prostate index levels, serum levels of prostate-specific antigen (PSA), and testosterone levels compared to animals treated with testosterone alone, when administered for 28 days. Histological examination indicated that febuxostat dramatically ameliorated pathological changes in the prostate architecture compared to the testosterone group. Similarly, febuxostat markedly improved testosterone-induced oxidative stress by inhibiting the increase in lipid peroxide and nitrite content, and by reducing the level of depletion of reduced glutathione (GSH) and superoxide dismutase (SOD) activity, which significantly reduced the prostate content of pro-inflammatory cytokines, including tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6). Furthermore, febuxostat significantly reduced the prostatic content, both in terms of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) messenger ribonucleic acid (mRNA) levels, and of protein levels. Moreover, compared to the testosterone group, febuxostat's beneficial effects prevented the increase in growth factors, comprising vascular endothelial cell growth factor A (VEGF-A) and transforming growth factor beta (TGF-ß) protein levels. Its ameliorating effects were equal to those of finasteride, which is the most widely used remedy for BPH. In conclusion, this study provides novel evidence that febuxostat experimentally attenuates testosterone-induced BPH in rats, at least in part by inhibiting iNOS/COX-2 and VEGF/TGF-ß pathways.

Fenofibrate ameliorates testicular damage in rats with streptozotocin-induced type 1 diabetes: role of HO-1 and p38 MAPK.

BACKGROUND: Since diabetes mellitus type-1 (DM-1) induces testicular oxidative and inflammatory damage with finally an ultimate male infertility, and as fenofibrate (FEN) plays an important antioxidant and anti-inflammatory role, the aim of the present study was to investigate the effects of FEN on diabetes-induced reproductive damage and clarifying the underlying related mechanisms. METHODS: DM-1 was induced in male Wistar rats by a single intraperitoneal injection of streptozotocin (50 mg/kg). FEN (100 mg/kg/day, orally) was administrated to diabetic rats for 4 weeks. Testicular damage was detected by estimation of both testicular and body weights, assessment of serum testosterone, testicular oxidative stress parameters (malondialdehyde and nitric oxide levels) and testicular oxidant defenses (reduced glutathione, superoxide dismutase and hemeoxygenase-1). Expressions of the inflammatory markers (inducible nitric oxide synthase, p38 mitogen-activated protein kinase (MAPK), tumor necrosis factor alpha, interleukin-6 and apoptotic marker (caspase-3) were evaluated in testicular tissue. Our results were confirmed by histopathological examination of testicular tissues. RESULTS: Diabetic testicular damage was proved by both biochemical and histopathological examinations. FEN treatment reversed diabetic testicular damage; normalized the serum testosterone level, improved anti-oxidative capacity, ameliorated the pro-inflammatory cytokine expression in testicular tissue with the down regulation of p38 MAPK mediated-testicular apoptosis. CONCLUSION: FEN treatment exerted a protective effect against streptozotocin-induced diabetic reproductive dysfunction not only through its powerful antioxidant and hypoglycemic effects, but also through its anti-inflammatory and anti-apoptotic effect via down-regulation of testicular p38 MAPK expression in diabetic rats.

Role of nitric oxide in mediating the cardioprotective effect of agomelatine against isoproterenol-induced myocardial injury in rats.

Myocardial infarction (M/I) is a common cause of mortality worldwide. Agomelatine (AGO), a potent melatonin receptor agonist, proved to have an anti-inflammatory and antioxidant effect. The present study aimed to explore the cardioprotective effect of AGO on isoproterenol (ISO)-induced myocardial injury in a rat model and determine the role of nitric oxide (NO) in mediating this beneficial effect. Rats were randomly divided into 6 groups and treated for 12 days. Group 1, control, received normal saline. Group 2, ISO group, received ISO (100 mg/kg, i.p.) in 11th and 12th days. Group 3, positive control group, received atenolol (100 mg/kg/day) + ISO. Group 4, AGO-treated group, received AGO (80 mg/kg/day) + ISO. Group 5, L-NNA + ISO, received L-NG-nitro arginine (L-NNA) (25 mg/kg, orally) + ISO. Group 6, AGO + L-NNA + ISO, co-treated with AGO + ISO + L-NNA. Serum cardiac enzymes and cardiac tissue oxidative stress parameters were assessed along with histopathological evaluation. Gene expression quantification of nuclear factor erythroid 2 (Nrf-2) and heme oxygenase-1 (HO-1) were assessed. Immunoexpression of inducible NO synthase (iNOS) and caspase-3 were evaluated. The outcomes proved that ISO significantly increased serum cardiac enzymes, with histopathological changes of myocardial tissue along with a major increase in oxidative, inflammatory, and nitrosative stress, besides a reduction in cardiac Nrf-2 and HO-1 gene expressions with marked myocardial cell apoptosis. However, pretreatment with AGO significantly reversed these profound ISO myocardial damaging effects. AGO protects against ISO-induced myocardial injury through its antioxidant, anti-inflammatory, and anti-apoptotic effects with modulation of NOS enzymes.

Possible mechanisms mediating the protective effect of cilostazol in L-arginine induced acute pancreatitis in rats: role of cGMP, cAMP, and HO-1.

Acute pancreatitis (AP) is an inflammatory disorder with a high mortality rate. Cilostazol is a selective phosphodiesterase-3 inhibitor drug that is commonly used as an antiplatelet, antithrombotic, and vasodilator drug. It exhibits antioxidant, anti-inflammatory, and anti-apoptotic activities, but its effect on AP has not been fully elucidated yet. The present study aimed to investigate the effects of cilostazol on L-arginine-induced AP and the possible protective mechanisms. A rat model of AP was established by a single i.p. injection of 3-g/kg L-arginine on day 13 of the experiment. The treated groups received a single daily oral dose of either 100 or 300 mg/kg/day for 14 consecutive days. Rats with AP showed histopathological changes of pancreatic tissue injury together with increased serum amylase enzyme activity and decreased serum insulin, pancreatic adiponectin, and cGMP levels. Moreover, AP rats showed increased pancreatic inflammatory biomarker (TNF-α, VCAM-1, and MPO) levels with decreased anti-inflammatory IL-10 levels. In addition, oxidative stress biomarkers (MDA and NO) were increased in AP with decreased antioxidant SOD activity and GSH level. Moreover, HO-1 immunostaining was increased in the AP group. Cilostazol pretreatment reversed the histopathological change; decreased the amylase activity and the levels of TNF-α, VCAM-1, and MPO; and increased the levels of insulin, adiponectin, cGMP, cAMP, and IL-10. Moreover, cilostazol decreased MDA and NO but increased SOD and GSH. Lastly, cilostazol increased the HO-1 immunostaining more than in the AP group. These data suggest that cilostazol protects against L-arginine-induced AP, which may be related to an increase in cGMP, cAMP, and upregulation of HO-1 with subsequent anti-inflammatory and antioxidant properties.

Cilostazol protects against cyclophosphamide-induced ovarian toxicity in female rats: role of cAMP and HO-1.

Purpose: Cancer rates have been increased among women of reproductive age nowadays. Hence, many young female will be exposed to chemotherapeutic agents as cyclophosphamide (CP), carrying the hazards on female fertility. Cilostazol is a selective phosphodiesterase-3 inhibitor drug which exhibits antioxidant, anti-inflammatory, and anti-apoptotic activities. We aimed in this study to explore the possible protective effects of cilostazol against CP-induced ovarian damage in female rats.Methods: Cilostazol (10 mg/kg/day) was administered orally for 10 days in presence and absence of CP (150 mg/kg IP single dose) treatment. Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), estrogen (E2), and anti-Müllerian hormone (AMH) levels were determined. Ovarian oxidative stress parameters along with inflammatory biomarkers were measured. 3,5-Cyclic adenosine monophosphate (cAMP) ovarian level was detected. Ovarian histopathological examination and caspase-3 immunohistochemical study were evaluated.Results: CP-treated rats showed a significant increase in serum levels of FSH and LH with decreased serum E2 and AMH levels with an increase in the ovarian inflammatory and oxidative stress biomarkers besides a significant decrease in cAMP ovarian level with an evident histopathological picture of ovarian damage and a high caspase-3 immunoexpression. Cilostazol pretreatment significantly restored the distributed hormonal levels, the oxidative stress and inflammatory biomarkers to their normal levels with marked improvement in histopathological picture of ovarian damage with a significant decrease in caspase-3 immunoexpression.Conclusions: These data suggest that cilostazol protects against CP- induced ovarian damage, which may be related to an increase in cAMP with subsequent anti-inflammatory, antioxidant, and anti-apoptotic properties.

Sitagliptin protects male albino rats with testicular ischaemia/reperfusion damage: Modulation of VCAM-1 and VEGF-A.

Twisting of the spermatic cord is considered a popular problem in the urological field, which may lead to testicular necrosis and male infertility. Sitagliptin, a glucose-lowering agent, proved to have a vindicatory function in myocardial and renal ischaemia/reperfusion (I/R), but its role in testicular I/R has not yet been studied. The current work investigates its capability to recover the testicular I/R injury with shedding more light on the mechanism of its action. Four groups were used: sham, sham pretreated with sitagliptin, I/R and sitagliptin/I/R-pretreated groups. The outcomes proved that I/R significantly decreased the serum testosterone, with a major increase in oxidative, inflammatory and nitrosative stress, along with a reduction in testicular vascular endothelial growth factor-A level with marked germinal cell apoptosis. However, pretreatment with sitagliptin significantly reversed the profound testicular I/R damaging effects, on the basis of its antioxidant, anti-inflammatory and anti-apoptotic activities with the ability of recuperation of the testicular vascularity.