Hepatoprotective effect of Ginkgo biloba extract against methotrexate-induced hepatotoxicity via targeting STAT3/miRNA-21 axis.

The usage of the chemotherapeutic agent methotrexate (MTX) was associated with hepatotoxicity that minimized its clinical use. The Ginkgo biloba extract (GBE) was used before to alleviate the MTX-induced liver injury through its antioxidant activity. This work was carried out to elucidate other molecular hepatoprotective mechanisms of GBE via examining the IL-6/STAT3 pathway in addition to the miRNA-21 expression in hepatic tissue. Sprague Dawley rats were allocated into four groups: normal control (NC); Ginkgo biloba extract control (GBEC); methotrexate (MTX); and Ginkgo biloba extract and methotrexate (GBE + MTX) group. GBE was administered orally 60 mg/kg/day for 10 days while MTX was intraperitoneally injected with 20 mg/kg on day 5. After the experiment, the serum was separated for liver enzyme determination while liver tissues were collected for biochemical and histopathological examinations. MTX induced marked elevation in the liver enzymes, hepatic IL-6, and HGF mRNA expressions, phospho-STAT3/STAT3 ratio, and miRNA-21 hepatic expression when compared with the NC group. Liver injury was observed histopathologically after MTX. The GBE administration reversed these biochemical alterations and improved liver histopathology. The hepatoprotective mechanism of GBE against MTX-induced hepatotoxicity via the modulation of the IL-6/STAT3 signaling pathway and the downregulation of the miRNA-21 hepatic expression was reported for the first time.

Hepatoprotective effect of arjunolic acid against cisplatin-induced hepatotoxicity: Targeting oxidative stress, inflammation, and apoptosis.

Minimizing the adverse effects of chemotherapeutic agents remains a therapeutic challenge. Cisplatin (CP) induces hepatotoxicity through activation of oxidative stress, inflammation, and apoptosis cascades which is considered a significant drawback. Thus, this study aimed to highlight the possible hepatoprotective role of arjunolic acid (Arj) in a rat model of CP-induced hepatotoxicity. Four groups of rats were included; the normal control group, Arj control group, CP group which was injected with 7.5 mg/kg CP intraperitoneally to induce hepatotoxicity, and the treated group (Arj + CP), which was orally administered 20 mg/kg Arj for 10 days with a CP hepatotoxic dose on day 5. Blood and liver tissues were assembled for analysis at the end of the study. Pretreatment with Arj exhibited a marked improvement in liver function as well as histopathology when compared with the CP group. Moreover, Arj suppressed the oxidative stress in hepatic tissue by significantly decreasing malondialdehyde and nitric oxide contents along with markedly elevating the levels of superoxide dismutase, catalase, and reduced glutathione when compared with CP injected rats. Attenuation of hepatic inflammation and apoptosis was also reported with Arj treatment through the marked reduction in the proinflammatory cytokine tumor necrosis factor α level as well as the apoptotic marker caspase-3 protein expression in comparison to the CP group. This study explored for the first time the Arj hepatoprotective effect against CP-induced hepatotoxicity through its antioxidant, anti-inflammatory, and antiapoptotic activities.

Renoprotective effect of vildagliptin following hepatic ischemia/reperfusion injury.

Remote renal injury is a drastic consequence of hepatic ischemia/reperfusion (IR) injury. Vildagliptin (V) is a dipeptidyl peptidase-4 inhibitor that has a hepatorenal protective effect against models of liver and renal IR. This research was done to explore the protective role of vildagliptin against renal injury following hepatic IR injury as well as the possible involvement of transforming growth factor-beta (TGF-ß)/Smad/alpha-smooth muscle actin (α-SMA) expressions in the pathophysiological mechanism of the remote renal injury. Three groups of male Wistar rats were organized into: sham group, IR group, and V + IR group in which 10 mg/kg/day of vildagliptin was pretreated for 10 days intraperitoneally. Blood in addition to renal and hepatic tissue samples was used for biochemical and histopathological studies. Hepatic IR induced a marked increase in serum creatinine, blood urea nitrogen, liver enzymes, renal nitric oxide, malondialdehyde, tumor necrosis factor-alpha levels with a marked upregulation of renal mRNA expressions of TGF-ß, Smad2, Smad3, and α-SMA in addition to a marked decline in renal catalase content comparing to the sham group. Abnormal histopathological findings of hepatic and renal injury were detected in the IR group. Vildagliptin significantly improved these biochemical markers as well as the histopathological changes. The upregulation of renal TGF-ß/Smad/α-SMA mRNA expressions was involved for the first time in the pathogenesis of the renal injury following hepatic IR and vildagliptin ameliorated this renal injury through blocking these expressions.

Antineoplastic Activity of Chrysin against Human Hepatocellular Carcinoma: New Insight on GPC3/SULF2 Axis and lncRNA-AF085935 Expression.

The natural flavonoid chrysin possesses antiproliferative activity against various types of cancers, including hepatocellular carcinoma (HCC), which is a common malignancy. However, the exact mechanism of chrysin antiproliferative activity remains unclear. This research was executed to explore the impact of chrysin on glypican-3 (GPC3)/sulfatase-2 (SULF2) axis and lncRNA-AF085935 expression in HCC using HepG2 cells. Cisplatin (20, 50, 100 µg/mL), chrysin (15, 30, and 60 µg/mL) and the combination of 50 µg/mL cisplatin with different concentrations of chrysin were applied for 24/48 h. Cell viability was determined by MTT assay. Protein levels of GPC3 and SULF2 were measured by ELISA at 24/48 h. GPC3 immunoreactivity was detected by immunocytochemistry. Moreover, GPC3 and SULF2 mRNA expressions in addition to lncRNA-AF085935 expression were assessed by qPCR at 48 h. The GPC3 protein, immunostaining and mRNA levels, SULF2 protein and mRNA levels, as well as lncRNA-AF085935 expression, were decreased significantly with cisplatin and chrysin alone when compared with the control untreated HepG2 cells. However, the combination treatment exhibited a better chemopreventive effect in a dose- and time-dependent manner. This study demonstrated, for the first time, the antiproliferative activity of chrysin against HCC through the suppression of the GPC3/SULF2 axis along with the downregulation of lncRNA-AF085935 expression. Synergistic effect of chrysin with cisplatin could potentiate their antiproliferative action in a dose- and time-dependent manner.

Uroprotective mechanism of quercetin against cyclophosphamide-induced urotoxicity: Effect on oxidative stress and inflammatory markers.

The urotoxicity is a common complication associated with patients receiving cyclophosphamide (CYP). This study was designed to investigate the uroprotective mechanism of quercetin (Quer) flavonoid against CYP induced urotoxicity via determination of oxidative stress markers as well as inflammatory mediators in bladder tissue. Forty male Wistar rats were divided into four groups; Normal group: received saline for 10 days. Quer control group: received quercetin 50 mg/kg/day for 10 days. CYP group: received saline for 10 days and injected with a single dose of 150 mg/kg CYP intraperitoneal (i.p) at day 8. The Quer + CYP group: received Quer 50 mg/kg/day for 10 days plus CYP 150 mg/kg i.p. injection at day 8. The CYP injection produced a significant elevation in bladder contents of malondialdehyde (MDA), and nitric oxide (NO), and bladder protein levels and expressions of tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) in addition to the upregulation of cyclooxygenase-2 (COX-2) bladder gene expression. Also, CYP injection showed a marked reduction in bladder levels of catalase, superoxide dismutase (SOD), and IL-10 when compared with normal group. Moreover, histopathological examination of the bladder showed degenerative alterations, severe edema, and inflammation following CYP injection. Quer attenuated the biochemical markers and histopathological changes induced by CYP. The uroprotective effect of Quer was exerted by restoring the balance between oxidative/antioxidative status and pro-/anti-inflammatory cytokines via its antioxidant and anti-inflammatory activities.

Amelioration of cisplatin-induced nephrotoxicity in rats by triterpenoid saponin of Terminalia arjuna.

BACKGROUND: Cisplatin is a potent anti-tumor compound. Nephrotoxicity-inducing oxidative stress is a common side effect. This study was conducted to find out whether, the triterpenoid saponin of Terminalia arjuna (TA), Arjunolic acid which is a natural antioxidant, could prevent cisplatin-induced renal toxicity and if so, explore its possible renoprotective mechanism. METHODS: Thirty male Sprague-Dawley rats were divided into three groups: CONTROL GROUP: rats received saline injection, cisplatin group: rats injected intraperitoneally with 7 mg/kg cisplatin and Arjunolic acid group: rats received 20 mg/kg Arjunolic acid daily for 10 days with cisplatin injection on day 5. Serum creatinine and blood urea nitrogen (BUN) were determined and kidney sections were obtained for histopathology. Oxidative stress was evaluated in kidney homogenates by measuring malondialdehyde (MDA), reduced glutathione (GSH) and nitric oxide (NO) levels. Renal gene expressions of transforming growth factor-beta (TGF-ß), nuclear factor-kappa B (NF-κB), kidney injury molecule-1 (Kim-1) and B cell lymphoma-2 (Bcl-2) were estimated. RESULTS: Cisplatin-treated rats showed a significant reduction in renal GSH and a significant elevation of serum creatinine, BUN, MDA and NO renal levels when compared with control. Moreover, upregulation of TGF-ß, NF-κB and Kim-1 along with downregulation of Bcl-2 renal expressions were also observed in cisplatin-treated rats in comparison to control. All these markers were significantly reversed by TA triterpenoid saponin administration. CONCLUSION: Arjunolic acid ameliorated the nephrotoxic biochemical changes induced by cisplatin supporting its renoprotective effects which may be mediated by attenuation of oxidative stress markers, downregulation of renal expressions of fibrotic (TGF-ß), inflammatory (NF-κB) and kidney injury (Kim-1) markers along with upregulation of renal antiapoptotic marker (Bcl-2) gene expressions.

Cisplatin-induced testicular toxicity in rats: the protective effect of arjunolic acid.

In the present study, the effect of arjunolic acid on testicular damage induced by intraperitoneal injection of rats with 7 mg/kg cisplatin was studied. Cisplatin induced a significant reduction in testicular weights, plasma testosterone, and testicular reduced glutathione levels in addition to a significant elevation of testicular malondialdehyde levels and testicular gene expressions of inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), and p38 mitogen-activated protein kinase (MAPK) when compared with the control group (p < 0.05). Lower tubular diameters and depletion of germ cells and irregular small seminiferous tubules with Sertoli cells only were observed in the cisplatin group. Arjunolic acid administration significantly corrected the changes in both biochemical and histopathological parameters. Arjunolic acid plays a significant protective role against cisplatin-induced testicular injury by attenuating oxidative stress parameters along with downregulation of iNOS, TNF-α, and p38-MAPK testicular expressions.

Rutin mitigates acetic acid-induced ulcerative colitis: novel coloprotective mechanism.

Background: Ulcerative colitis, an inflammatory bowel disease, is characterized by a status of oxidative stress and inflammation. Rutin is a natural flavonoid with many pharmacological activities and its role in acetic acid-induced ulcerative colitis through the high mobility group B1 (HMGB1)/ toll-like receptor-4 (TLR4)/ myeloid differentiation primary response protein 88 (MYD88)/ nuclear factor-kB (NF-kB) signaling pathway needs to be explored. Methods: Four experimental groups were divided into control group, rutin group: treated with 100 mg/kg/day rutin orally for 10 days, acetic acid (AA) group: given intracolonic instillation of AA to induce ulcerative colitis, and acetic acid with rutin treatment (AA/Rutin) group. Results: Acetic acid caused a marked increase in the colon weight/length ratio and induced colonic histopathological changes, leading to a marked rise in the colonic histopathological scores. Acetic acid exhibited a significant rise in LDH and CRP serum levels as well as TOS colonic levels, accompanied by a marked decline in TAS colonic contents compared to the control group. Moreover, AA-induced activation of the HMGB1/TLR4/MYD88/NF-kB signaling pathway. Rutin demonstrated a significant decrease in the colon weight/length ratio, ameliorated the colonic histopathological changes induced by AA, and exhibited a marked decline in the colonic histopathological scores. Rutin showed a significant decrease in serum LDH, and CRP levels as well as colonic TOS contents when compared with the AA group. Rutin suppressed the colonic activation of the HMGB1/TLR4/MYD88/NF-kB signaling pathway. Conclusion: Rutin could be a promising coloprotective agent against AA-induced ulcerative colitis by targeting the HMGB1/TLR4/MYD88/NF-kB signaling pathway.

Alleviation of chemotherapy-induced acute lung injury via NLRP3/ ASC/ Caspase-1 signaling pathway.

Acute lung injury has been reported following various chemotherapeutic agents administration. Several pathways for lung injury have been speculated however, the exact mechanism of the lung injury induced by methotrexate (MTX) is yet to be defined. The potential protective effect of Ginkgo biloba extract (GB), a Chinese herbal medicine, against MTX-induced lung injury is still not reported. Therefore, this study was performed to examine the possible implication of NLRP3 inflammasome and miRNA-21 in the pathogenesis of the MTX-induced lung injury as well as the protective role of GB in ameliorating the induced lung injury. Rats received GB (100 mg/kg/day, orally) for 10 days and MTX (20 mg/kg single dose, intraperitoneally) on the fifth day. MTX-induced lung injury was manifested by lung histopathology. MTX exhibited a marked increase in lung malondialdehyde beside a notable decrease in lung reduced glutathione. Moreover, MTX injection activated the lung NLRP3 inflammasome by significant upregulation of the NLRP3, ASC, caspase-1 lung mRNA expressions and protein levels in addition to lung NF-kBp65 protein expression, and miRNA-21 expression when compared with the normal control group. However, GB administration mitigated lung injury and inhibited the NLRP3 activation. This study is the first report to reveal the involvement of NLRP3 inflammasome in the pathogenesis of MTX-induced lung injury and also to show that the administration of GB alleviates the lung injury induced by MTX via suppressing the oxidative stress, restoring the antioxidant activity, blocking the NLRP3/ASC/Caspase-1 signaling and downregulating the NF-kBp65 protein expression ae well as miRNA-21 expression in lung tissue.

IL-17/Notch1/STAT3 Pathway Contributes to 5-Fluorouracil-Induced Intestinal Mucositis in Rats: Amelioration by Thymol Treatment.

5-Fluorouracil (5-FU) is an anticancer drug with intestinal mucositis (IM) as a deleterious side effect. Thymol is a monoterpene phenol which has been reported to possess an antioxidant and anti-inflammatory activity versus 5-FU-induced IM. The Notch pathway affects multiple cellular activities, such as cellular proliferation, in addition to inflammatory responses modulation. Accordingly, this work was carried out in order to elucidate the role of the Notch pathway in 5-FU-induced IM and to further elucidate the immunomodulatory protective mechanisms of thymol. Experimental rats were divided randomly into four groups: Control, 5-FU, 5-FU+thymol (60 mg/kg/day), and 5-FU+thymol (120 mg/kg/day). 5-FU was injected intraperitoneally at a dose of 150 mg/kg on days 6 and 7, while thymol was orally administered daily for 11 days. By the end of the study, intestinal tissues were collected for the determination of IL-17, CD4, CD8, Notch1, Hes-1, pSTAT3, and STAT-3 protein expressions. The effect of thymol on 5-FU cytotoxicity was also examined using WST1 assay. 5-FU induced a marked increase in IL-17 levels, along with a marked downregulation of CD4 and the upregulation of CD8, Notch1, Hes-1 protein expressions, and activation of STAT3 in the intestinal tissue when compared with the control group. Thymol ameliorated the changes that occurred in these parameters. Additionally, cytotoxicity testing revealed that thymol augmented the antiproliferative action of 5-FU against breast and colorectal human cancer cell lines. This study was the first to show that the IL-17/Notch1/STAT3 pathway is involved in the molecular mechanism of 5-FU-induced IM, as well as the immunomodulatory activity of thymol.

Glycyrrhizic acid ameliorates submandibular gland oxidative stress, autophagy and vascular dysfunction in rat model of type 1 diabetes.

The burden of diabetes mellitus (DM) and associated complications is increasing worldwide, affecting many organ functionalities including submandibular glands (SMG). The present study aims to investigate the potential ameliorative effect of glycyrrhizic acid (GA) on diabetes-induced SMG damage. Experimental evaluation of GA treatment was conducted on a rat model of type I diabetes. Animals were assigned to three groups; control, diabetic and GA treated diabetic groups. After 8 weeks, the SMG was processed for assessment of oxidative stress markers, autophagy related proteins; LC3, Beclin-1 and P62, vascular regulator ET-1, aquaporins (AQPs 1.4 and 5), SIRT1 protein expressions in addition to LC3 and AQP5 mRNA expressions. Also, parenchymal structures of the SMG were examined. GA alleviated the diabetes-induced SMG damage via restoring the SMG levels of oxidative stress markers and ET-1 almost near to the normal levels most probably via regulation of SIRT1, AQPs and accordingly LC-3, P62 and Beclin-1levels. GA could be a promising candidate for the treatment of diabetes-induced SMG damage via regulating oxidative stress, autophagy and angiogenesis.

Alleviation of remote lung injury following liver ischemia/reperfusion: Possible protective role of vildagliptin.

Lung injury is a serious condition encountered following hepatic ischemia/reperfusion (IR). This study aimed to explore whether a dipeptidyl peptidase-4 inhibitor agent vildagliptin (V) could alleviate the lung injury caused by hepatic IR in a rat model and if so elucidate its molecular protective mechanism. Three groups of rats were used. Sham group: received normal saline and exposed to a sham operation, IR group: received normal saline and subjected to the operation of hepatic I (45 min)/ R (180 min), V+IR group: received for 10 days intraperitoneal injection of V (10 mg/kg/day). After reperfusion, liver and lung were collected for biochemical and histological evaluation. Hepatic IR exhibited significant elevation in serum alanine aminotransferase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) enzyme levels, serum and lung malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-α) in addition to lung nitric oxide (NO) levels, hypoxia-inducible factor 1-alpha (HIF-1α) mRNA and protein levels, hepatocyte growth factor (HGF) mRNA expression, and inducible nitric oxide synthase (iNOS) mRNA and protein expressions in lung tissue along with a marked reduction in the serum and lung content of catalase in comparison to the sham group. Moreover, liver and lung injury in the IR group was detected by histopathological examination. Vildagliptin ameliorated markedly the biochemical changes as well as liver and lung architecture in comparison to the IR group. Vildagliptin mitigated the induced lung injury by hepatic IR via suppression of oxidative stress markers, pro-inflammatory cytokine TNF-α as well as the HIF1-α/iNOS/HGF expressions in lung tissue.

Neuroprotective Potential of Bone Marrow-Derived Mesenchymal Stem Cells Following Chemotherapy.

Cisplatin (CP) is extensively used in the medical oncology field for malignancy treatment, but its use is associated with neurological side effects that compromise the patients' quality of life. Cytotherapy is a new treatment strategy for tissue damage that has recently emerged. The use of bone marrow-derived mesenchymal stem cells (BM-MSCs) was investigated for its therapeutic potential against CP-induced chemobrain as well as various models of brain damage. This study was carried out to elucidate, for the first time, the role of the intravenous injection (IV) of BM-MSCs against CP-induced neurotoxicity in a rat model through investigation of the parameters of oxidative stress, inflammation, and apoptosis in brain tissue. A rat model of neurotoxicity was generated by intraperitoneal injection of 7.5 mg/kg CP while 2 × 106 BM-MSCs was given by IV as a therapeutic dose. Injection of CP led to a significant rise in malondialdehyde and nitric oxide levels accompanied by a marked depletion of superoxide dismutase and reduced glutathione content in brain tissue in comparison to the normal control (NC) rats. Furthermore, a remarkable rise in the brain levels of inflammatory cytokines interleukin (IL)-1ß and IL-6, together with the expression of apoptotic marker caspase-3, and the downregulation of the brain expression of proliferating marker Ki-67 in brain tissue were detected in the CP group compared to the NC group. Histopathological alterations were observed in the brain tissue of the CP group. BM-MSCs mitigated the biochemical and histopathological alterations induced by CP without affecting brain cell proliferation. BM-MSCs could be used as a promising neuroprotective agent against CP-induced neurotoxicity.

Ginkgo biloba Extract Attenuates Methotrexate-Induced Testicular Injury in Rats: Cross-talk Between Oxidative Stress, Inflammation, Apoptosis, and miRNA-29a Expression.

Ginkgo biloba leaf extract (GIN) is a popular Chinese herbal medicine. It has a nephroprotective effect against the nephrotoxicity induced by the chemotherapeutic agent methotrexate (MTX). This work was designed to explore the testicular protective role of GIN on MTX-induced testicular injury in a rat model. The experimental protocol lasted for 10 days for the 4 studied groups. First group: received saline (normal control, NC group). The second group was administered GIN (100 mg/kg/day) orally for 10 days (GIN C). Third group: injected with MTX (20 mg/kg ip) only on the fifth day (MTX group). Fourth group: administered GIN for 10 days with MTX injection on the fifth day (GIN+MTX group). MTX induced testicular injury as evident by a marked rise in the malondialdehyde (MDA) content, interleukin-6 (IL-6) and IL-1ß protein levels, nuclear factor kappa-B (NF-κB) protein expression, bcl-2 associated × protein (Bax) mRNA expression, p53 mRNA and protein expressions, and miRNA29-a expression along with a marked decline in the serum level of testosterone and superoxide dismutase (SOD) content in testicular tissue in relation to the NC group. Moreover, histopathological testicular damage with a notable decrease in the Johnsen score together with a significant elevation in the testicular injury score was observed in the MTX group in comparison to the NC group. The administration of GIN ameliorated the biochemical changes as well as the testicular histopathological findings and scores. GIN could protect against MTX-induced gonadotoxicity by its antioxidant, anti-inflammatory, antiapoptotic activities plus the regulation of the miRNA-29a testicular expression.

Candesartan in a rat model of testicular toxicity: New insight on its protective mechanism.

IMPACT STATEMENT: Cisplatin is a commonly used drug in the treatment of solid tumors and its application is associated with testicular toxicity. The effect of candesartan in cisplatin-induced testicular toxicity and its fundamental mechanism of action were investigated. Candesartan had certainly repaired the testicular injury and ameliorated both biochemical and histopathological changes. Candesartan mitigated the gonadotoxicity induced by cisplatin via antioxidative, anti-inflammatory, and antiapoptotic actions.

Ginkgo Biloba Extract Alleviates Methotrexate-Induced Renal Injury: New Impact on PI3K/Akt/mTOR Signaling and MALAT1 Expression.

Renal injury induced by the chemotherapeutic agent methotrexate (MTX) is a serious adverse effect that has limited its use in the treatment of various clinical conditions. The antioxidant activity of Ginkgo biloba extract (GB) was reported to mitigate renal injury induced by MTX. Our research was conducted to examine the nephroprotective role of GB versus MTX-induced renal injury for the first time through its impact on the regulation of phosphatidylinositol 3-kinase/protein kinase B/ mammalian target of rapamycin (PI3K/Akt/mTOR) signaling together with the renal level of TGF-ß mRNA and long non-coding RNA-metastasis-associated lung adenocarcinoma transcript-1 (MALAT1) expression. A group of adult rats was intraperitoneally (ip) injected with MTX 20 mg/kg as a single dose to induce kidney injury (MTX group). The other group of rats was orally administered with GB 60 mg/kg every day for 10 days (GB+ MTX group). The MTX increased the serum creatinine and urea levels, renal TGF-ß mRNA and MALAT1 expression, in addition to dysregulation of the PI3K/Akt/mTOR signaling when compared with normal control rats that received saline only (NC group). Moreover, renal damage was reported histopathologically in the MTX group. The GB ameliorated the renal injury induced by MTX and reversed the changes of these biochemical analyses. The involvement of PI3K/Akt/mTOR signaling and downregulation of TGF-ß mRNA and MALAT1 renal expressions were firstly reported in the nephroprotective molecular mechanism of GB versus MTX-induced renal injury.

The effect of natural antioxidants in cyclophosphamide-induced hepatotoxicity: Role of Nrf2/HO-1 pathway.

Hepatotoxicity induced by cyclophosphamide (Cyclo) is a major concern in clinical practice. This study was designed to investigate the possible cytoprotective effect of natural antioxidants as oleuropein and quercetin against Cyclo induced hepatotoxicity via the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. Male Wistar rats were randomly divided into six groups and treated for 10 days as follow: Group I (Normal control) received saline, group II (Oleu control): received orally oleuropein 30 mg/kg/day, group III (Quer control): administered orally quercetin 50 mg/kg/day, group IV (Cyclo): received saline and injected with single intraperitoneal (i.p) dose of Cyclo 200 mg/kg at day 5, group V (Oleu ttt): treated with oleuropein plus Cyclo i.p. injection at day 5, and group VI (Quer ttt): treated with quercetin plus Cyclo i.p. injection at day 5. Injection of Cyclo showed marked increase in serum transaminases and alkaline phosphatase, hepatic malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-⍺) levels along with significant reduction in hepatic reduced glutathione (GSH), superoxide dismutase (SOD), and catalase levels in addition to downregulation of hepatic Nrf2 and HO-1 expressions and reduction in hepatic nuclear Nrf2 binding activity when compared with normal group. Histopathological examination of Cyclo treated rats revealed hepatic damage. Both oleuropein and quercetin exhibited an improvement in the biochemical and histopathological findings. In conclusion, the natural antioxidants oleuropein and quercetin counteract the Cyclo induced hepatotoxicity through activation of Nrf2/HO-1 signaling pathway with subsequent suppression of oxidative stress and inflammation.

Vildagliptin Attenuates Hepatic Ischemia/Reperfusion Injury via the TLR4/NF-κB Signaling Pathway.

The Toll-like receptor-4 (TLR4)/nuclear factor kappa B (NF-κB) signaling pathway is vital in the pathogenesis of hepatic ischemia/reperfusion (HIR) injury. Dipeptidyl peptidase-4 (DPP4) inhibitors exert protective effects on IR injury of the kidney, heart, and lung; however, their effect on the liver is still unknown. Thus, the purpose of this study was to examine whether pretreatment with vildagliptin (Vilda), a DPP4 inhibitor, produces hepatic protection against IR injury and to investigate its influence on TLR4/NF-κB signaling in a rat model. Thirty male Wistar rats were divided into 3 groups: the sham group: subjected to a sham operation and received normal saline; the HIR group: subjected to HIR and received normal saline; and the Vilda + HIR group: subjected to HIR with pretreatment of 10 mg/kg/day Vilda for 10 days intraperitoneally. Hepatic ischemia lasted for 45 minutes followed by 3-hour reperfusion; then blood and liver samples were collected for biochemical and histopathological examination. The HIR group produced a significant increase in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), hepatic malondialdehyde (MDA), nitric oxide (NO), and tumor necrosis factor alpha (TNF-α) levels and a significant reduction in the hepatic catalase level in comparison to the sham group. Moreover, a significant upregulation of gene and protein expressions of TLR4, NF-κB, and high-mobility group box-1 (HMGB1) along with caspase-3 protein expression was observed in the HIR group when compared with the sham group. Histopathological examination of the liver from the HIR group showed necrosis, sinusoidal congestion, hemorrhage, and hepatocyte degeneration. Administration of Vilda ameliorated the biochemical and histopathological changes caused by HIR. Vildagliptin showed for the first time a hepatoprotective effect in HIR injury through downregulation of TLR4/NF-κB/HMGB1 and caspase-3 hepatic expressions.

Oleuropein potentiates anti-tumor activity of cisplatin against HepG2 through affecting proNGF/NGF balance.

AIMS: Oleuropein is considered as a new chemotherapeutic agent in human hepatocellular carcinoma (HCC) while, its exact underlying molecular mechanism still not yet explored. In addition, cisplatin is a standard anticancer drug against solid tumors with toxic side effects. Therefore, we conducted this study to assess antitumor activity of oleuropein either alone or in combination with cisplatin against HepG2, human HCC cell lines, via targeting pro-NGF/NGF signaling pathway. MAIN METHODS: HepG2 cells were treated with cisplatin (20, 50, 100 µM) and oleuropein (100, 200, 300 and 400 µM) as well as some of the cells were treated with 50 µM cisplatin and different concentrations of oleuropein. Gene expressions of nerve growth factor (NGF), matrix metalloproteinase-7 (MMP-7) and caspase-3 were evaluated by real time-PCR. In addition, protein levels of NGF and pro-form of NGF (pro-NGF) were measured by ELISA while, nitric oxide (NO) content was determined colorimetrically. KEY FINDINGS: Cisplatin treatment showed a significant elevation of NO content and pro-NGF protein level with a marked reduction of NGF protein level in addition to the upregulation of caspase-3 along with downregulation of MMP-7 gene expressions in a dose-dependent manner. However, the combination of 50 µM cisplatin and 200 µM oleuropein showed the most potent effect on the molecular level when compared with oleuropein or cisplatin alone. SIGNIFICANCE: Our results showed for the first time that the anti-tumor activity of oleuropein against HCC could be attributed to influencing the pro-NGF/NGF balance via affecting MMP-7 activity without affecting the gene expression of NGF. Concurrent treatment with both oleuropein and cisplatin could lead to more effective chemotherapeutic combination against HCC.