Effect of captopril and telmisartan on methotrexate-induced hepatotoxicity in rats: impact of oxidative stress, inflammation and apoptosis

Modified citrus pectin ameliorates methotrexate-induced hepatic and pulmonary toxicity: role of Nrf2, galectin-3/TLR-4/NF-κB/TNF-α and TGF-β signaling pathways

Introduction

Methotrexate (MTX) is a frequently utilized anti-inflammatory and anticancer agent. Its potential liver and lung toxicity often limits its clinical effectiveness. We conducted this study to demonstrate the possible protective impacts of a natural galectin-3 (Gal-3) inhibitor, modified citrus pectin (MCP), against MTX-induced liver and lung toxicity and verify the potential signaling pathways of these suggested effects. In vitro, the cytotoxicity of MCP and its modulatory effect on MTX cytotoxic efficacy were assessed.

Methods

Four groups of rats were used: control, MTX (40 mg/kg, single intraperitoneal injection on day 9), MTX + MCP (200 mg/kg/day, orally, for 2 weeks), and MCP alone. MCF7, Nalm6, and JEG3 cell lines were used for the in vitro cytotoxicity assay.

Results

MCP counteracted liver and lung toxicity evidenced by ameliorating the markers of liver and lung functions. Moreover, MCP minimized oxidative stress elicited by MTX in lung and liver tissues, as indicated by reduced malondialdehyde levels, elevated levels of reduced glutathione, increased superoxide dismutase activity, and upregulated Nrf2 protein expression. In hepatic and pulmonary tissues, MCP downregulated the inflammatory signaling pathway, Gal-3/TLR-4/NF-κB/TNF-α. MCP pretreatment decreased TGF-β, collagen content, and cleaved caspase-3 levels. MCP enhanced the cytotoxicity of MTX in Nalm6 and JEG3 and did not interfere with its cytotoxicity in the MCF7 cell lines.

Discussion

MCP attenuated MTX-induced liver and lung toxicity through antioxidant, anti-fibrotic, anti-inflammatory, and anti-apoptotic influences, as demonstrated by the improved histopathological changes induced by MTX in pulmonary and hepatic tissues. Moreover, it increased MTX cytotoxicity in different human cell lines.

Mechanistic insight into the hepatoprotective effect of Moringa oleifera Lam leaf extract and telmisartan against carbon tetrachloride-induced liver fibrosis: plausible roles of TGF-β1/SMAD3/SMAD7 and HDAC2/NF-κB/PPARγ pathways

The increasing prevalence and limited therapeutic options for liver fibrosis necessitates more medical attention. Our study aims to investigate the potential molecular targets by which Moringa oleifera Lam leaf extract (Mor) and/or telmisartan (Telm) alleviate carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Liver fibrosis was induced in male Sprague-Dawley rats by intraperitoneal injection of 50% CCl4 (1 ml/kg) every 72 hours, for 8 weeks. Intoxicated rats with CCl4 were simultaneously orally administrated Mor (400 mg/kg/day for 8 weeks) and/or Telm (10 mg/kg/day for 8 weeks). Treatment of CCl4-intoxicated rats with Mor/Telm significantly reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities compared to CCl4 intoxicated group (P < 0.001). Additionally, Mor/Telm treatment significantly reduced the level of hepatic inflammatory, profibrotic, and apoptotic markers including; nuclear factor-kappa B (NF-κB), tumor necrosis factor-alpha (TNF-α), transforming growth factor-βeta1 (TGF-β1), and caspase-3. Interestingly, co-treatment of CCl4-intoxicated rats with Mor/Telm downregulated m-RNA expression of histone deacetylase 2 (HDAC2) (71.8%), and reduced protein expression of mothers against decapentaplegic homolog 3 (p-SMAD3) (70.6%) compared to untreated animals. Mor/Telm regimen also elevated p-SMAD7 protein expression as well as m-RNA expression of peroxisome proliferator-activated receptor γ (PPARγ) (3.6 and 3.1 fold, respectively p < 0.05) compared to CCl4 intoxicated group. Histopathological picture of the liver tissue intoxicated with CCl4 revealed marked improvement by Mor/Telm co-treatment. Conclusively, this study substantiated the hepatoprotective effect of Mor/Telm regimen against CCl4-induced liver fibrosis through suppression of TGF-β1/SMAD3, and HDAC2/NF-κB signaling pathways and up-regulation of SMAD7 and PPARγ expression.

Insights gained into the injury mechanism of drug and herb induced liver injury in the hepatic microenvironment

Drug-Induced Liver Injury (DILI) and herb Induced Liver Injury (HILI) continues to pose a substantial challenge in both clinical practice and drug development, representing a grave threat to patient well-being. This comprehensive review introduces a novel perspective on DILI and HILI by thoroughly exploring the intricate microenvironment of the liver. The dynamic interplay among hepatocytes, sinusoidal endothelial cells, Kupffer cells, hepatic stellate cells, cholangiocytes, and the intricate vascular network assumes a central role in drug metabolism and detoxification. Significantly, this microenvironment is emerging as a critical determinant of susceptibility to DILI and HILI. The review delves into the multifaceted interactions within the liver microenvironment, providing valuable insights into the complex mechanisms that underlie DILI and HILI. Furthermore, we discuss potential strategies for mitigating drug-induced liver injury by targeting these influential factors, emphasizing their clinical relevance. By highlighting recent advances and future prospects, our aim is to shed light on the promising avenue of leveraging the liver microenvironment for the prevention and mitigation of DILI and HILI. This deeper understanding is crucial for advancing clinical practices and ensuring patient safety in the realm of DILI and HILI.

Oral Administration of Fermented Milk from Co-Starter Containing Lactobacillus plantarum Y44 Shows an Ameliorating Effect on Hypertension in Spontaneously Hypertensive Rats

Fermented dairy foods such as yogurt exhibit some beneficial effects on consumers, including relieving the symptoms of hypertension. This study aims to obtain fermented dairy products from a co-starter that have a great flavor and the auxiliary function of reducing blood pressure after longtime consumption. Commercial starter cultures composed of Lactobacillus delbrueckii subsp. bulgaricus CICC 6047 and Streptococcus thermophilus CICC 6038 were combined with Lactobacillus plantarum strains Y44, Y12, and Y16, respectively, as a combined starter culture to ferment the mixed milk of skim milk and soybean milk. The fermented milk produced using the combined starter culture mixed with L. plantarum Y44 showed an angiotensin-converting-enzyme (ACE) inhibitory activity (53.56 ± 0.69%). Some peptides that regulate blood pressure were released in the fermented milk, such as AMKPWIQPK, GPVRGPFPII, LNVPGEIVE, NIPPLTQTPV, and YQEPVL. In spontaneously hypertensive rat (SHR) oral-administration experiments compared with the gavage unfermented milk group, the gavage feeding of SHRs with the fermented milk produced using the combined starter culture mixed with L. plantarum Y44 significantly reduced the blood pressure of the SHRs after long-term intragastric administration, shown with the systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreasing by 23.67 ± 2.49 mmHg and 15.22 ± 2.62 mmHg, respectively. Moreover, the abundance of short-chain fatty acids (SCFA), bacterial diversity in the gut microbiota, and SCFA levels including acetic acid, propionic acid, and butyric acid in the feces of the SHRs were increased via oral administration of the fermented milk produced using the combined starter culture containing L. plantarum Y44. Furthermore, the ACE-angiotensin II (Ang II)-angiotensin type 1 (AT 1) axis was downregulated, the angiotensin-converting-enzyme 2 (ACE 2)-angiotensin(1-7) (Ang1-7)-Mas receptor axis of the SHRs was upregulated, and then the RAS signal was rebalanced. The fermented milk obtained from the combined starter culture shows the potential to be a functional food with antihypertension properties.

MicroRNAs in Anticancer Drugs Hepatotoxicity: From Pathogenic Mechanism and Early Diagnosis to Therapeutic Targeting by Natural Products

Patients receiving cancer therapies experience severe adverse effects, including hepatotoxicity, even at therapeutic doses. Consequently, monitoring patients on cancer therapy for hepatic functioning is necessary to avoid permanent liver damage. Several pathways of anticancer drug-induced hepatotoxicity involve microRNAs (miRNAs) via targeting mRNAs. These short and non-coding RNAs undergo rapid modulation in non-targeted organs due to cancer therapy insults. Recently, there has been an interest for miRNAs as useful and promising biomarkers for monitoring toxicity since they have conserved sequences across species and are cellular-specific, stable, released during injury, and simple to analyze. Herein, we tried to review the literature handling miRNAs as mediators and biomarkers of anticancer drug-induced hepatotoxicity. Natural products and phytochemicals are suggested as safe and effective candidates in treating cancer. There is also an attempt to combine anticancer drugs with natural compounds to enhance their efficiencies and reduce systemic toxicities. We also discussed natural products protecting against chemotherapy hepatotoxicity via modulating miRNAs, given that miRNAs have pathogenic and diagnostic roles in chemotherapy-induced hepatotoxicity and that many natural products can potentially regulate their expression. Future studies should integrate these findings into clinical trials by formulating suitable therapeutic dosages of natural products to target miRNAs involved in anticancer drug hepatotoxicity.

Exploring the role of ATP-sensitive potassium channel, eNOS, and P-glycoprotein in mediating the hepatoprotective activity of nicorandil in methotrexate-induced liver injury in rats

BACKGROUND

Methotrexate (MTX) is a commonly used chemotherapeutic agent; however, its clinical use is challenged by various types of injuries, including hepatotoxic side effects. Therefore, finding new protective drugs against MTX-induced toxicities is a critical need. Moreover, the different mechanisms mediating such effects are still not clear. The current study aimed to evaluate the possible ameliorative action of nicorandil (NIC) in MTX-induced hepatotoxicity and examine the roles of the ATP-sensitive potassium channel (KATP), endothelial nitric oxide synthase (eNOS), and P-glycoprotein (P-gp).

MATERIALS AND METHODS

Thirty-six male Wistar albino rats were used. NIC (3 mg/kg/day) was given orally for 2 weeks, and hepatotoxicity was induced by a single intraperitoneal injection of MTX (20 mg/kg) on the 11th day of the experiment. We confirmed the role of KATP by co-administering glimepiride (GP) (10 mg/kg/day) 30 min before NIC. The measured serum biomarkers were [alanine transaminase (ALT) and aspartate transaminase (AST)], total antioxidant capacity (TAC), malondialdehyde (MDA), nitric oxide (NOx), tumor necrosis factor-alpha (TNFα), superoxide dismutase (SOD), and P-gp. Histopathology, eNOS, and caspase-3 immunoexpression were evaluated.

RESULTS

The MTX group displayed hepatotoxicity in the form of elevations of ALT, AST, MDA, NOx, and caspase-3 immunoexpression. Furthermore, the histopathological examination showed marked liver injury. TAC, SOD, P-gp, and eNOS immunoexpression showed significant inhibition. In the protective group, all parameters improved (P value < 0.05).

CONCLUSION

NIC has an ameliorative action against MTX-induced hepatotoxicity, most probably via its antioxidant, anti-inflammatory, and anti-apoptotic functions together with the modulation of the KATP channel, eNOS, and P-glycoprotein.

Advantages of a Novel Model for Predicting Hepatic Fibrosis in Chronic Hepatitis B Virus Carriers Compared with APRI and FIB-4 Scores

BACKGROUND AND AIMS

Aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis-4 index (FIB-4) are widely used to assess liver fibrosis in chronic hepatitis B virus (HBV) infection. Currently, the definition of normal alanine aminotransferase (ALT) is controversial. We aimed to examine the diagnostic value of APRI and FIB-4 in chronic HBV carriers with different upper limits of normal (ULNs) for ALT.

METHODS

581 chronic HBV carriers were divided into the following four groups based on different ULNs for ALT: chronic HBV carriers I, II, III, and IV. Furthermore, 106 chronic HBV carriers formed an external validation group. Predictive values of APRI and FIB-4 were elucidated using the area under the curve (AUC). A liver fibrosis-predictive model-GPSA (named for its measure of gamma glutamyl transpeptidase, platelet count, HBsAg and albumin) was developed using multivariate logistic regression analysis.

RESULTS

In chronic HBV carriers I, the AUCs of APRI and FIB-4 were 0.680 and 0.609 for significant fibrosis and 0.678 and 0.661 for cirrhosis, respectively. The AUCs of GPSA for significant fibrosis in the training group, internal group, and external validation group were 0.877, 0.837, and 0.871, respectively. The diagnostic value of GPSA differed among chronic HBV carriers I, II, III, and IV, with AUCs for significant fibrosis being 0.857, 0.853, 0.868, and 0.905 and AUCs for cirrhosis being 0.901, 0.905, 0.886, and 0.913, respectively. GPSA showed a higher diagnostic value than APRI and FIB-4 for predicting significant fibrosis in the four groups.

CONCLUSIONS

The GPSA model allows for accurate diagnosis of liver fibrosis in chronic HBV carriers with different ULN for ALT.

Protective mechanisms of telmisartan against hepatic ischemia/reperfusion injury in rats may involve PPARγ-induced TLR4/NF-κB suppression

Hepatic ischemia-reperfusion (I/R) is an important cause of liver damage in many clinical situations. Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) is an inflammatory pathway activated in hepatic I/R injury. Telmisartan, a selective angiotensin II type 1 receptor antagonist and peroxisome proliferator-activated receptor-gamma (PPARγ) partial agonist, can inhibit the expression of pro-inflammatory cytokines. The present work investigated the possible protective effect of telmisartan against hepatic I/R injury and explored its possible mechanisms in rats. Rats were divided into four equal groups: sham-operated control, telmisartan-treated sham-operated control, I/R untreated, and I/R telmisartan-treated groups. Hepatic injury was evaluated biochemically by serum activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and histopathological examination. Hepatic oxidative stress biomarkers, myeloperoxidase level, PPARγ and TLR4 mRNA expression, and NF-κB and active caspase 3 immunoexpression were determined. The study showed that telmisartan attenuated hepatic I/R, as evidenced by decreased serum ALT and AST activities and confirmed by improvement of the histopathological changes. The protective effect of telmisartan was associated with modulation of oxidative stress parameters, myeloperoxidase level, PPARγ and TLR4 mRNA expression, and NF-κB and caspase 3 immunoexpression. Taken together, the current study showed that telmisartan could protect the rat liver from I/R injury. This hepatoprotective effect was attributed to, at least in part, increase in PPARγ expression and suppression of TLR4/NF-κB pathway.

The angiotensin-converting enzyme inhibitor, captopril, suppressed hepatic stellate cell activation via NF-kappaB or wnt3α/β-catenin pathway

Activation of hepatic stellate cells (HSC) is associated with hepatic fibrogenesis, which is one of complications of diabetes mellitus. Captopril possesses potent anti-inflammation, oxidative stress and fibrosis effects. However, the specific molecular mechanism of captopril in high glucose (HG)-induced hepatic stellate cells has not been elucidated. Following the treatment of HG or captopril treatment for rat hepatic stellate cells (HSC-T6), cell activities were detected by Cell Counting Kit-8 (CCK8) assay. Reactive oxygen species (ROS) levels were determined by ROS staining. The expression of inflammation-related proteins (Interleukin (IL)-1β, IL-6 and IL-8) and fibrosis-related proteins (fibronectin (FN), collagen I, collagen III, collagen IV, matrix metallopeptidase (MMP-2 and MMP-9) were determined by Western blot. Captopril significantly decreased HSC-T6 cell viability induced by HG in a dose-dependent manner, as well as decreased levels of malondialdehyde (MDA), ROS, pro-inflammatory markers and fibrosis-related proteins, while upregulated superoxide dismutase (SOD) activities. We further found that captopril decreased the ratio of p-IκBα/IκBα and the ratio of p-p65/p65. Intriguing, phorbol myristate acetate (PMA) or LiCl was able to significantly reverse the captopril-induced alteration of oxidative stress-, inflammation- and fibrosis-marker levels. In conclusion, in HG-stimulated HSC-T6 cells, captopril displayed a potent ability to inhibit oxidative stress, inflammation and hepatic fibrogenesis via NF-kappaB or wnt3α/β-catenin. These results demonstrated the mechanism of captopril as well as the role of the NF-kappaB or wnt3α/β-catenin on HSC-T6 activation induced by HG.

Telmisartan alleviates alcohol-induced liver injury by activation of PPAR-γ/ Nrf-2 crosstalk in mice

Excessive consumption of alcohol may induce severe liver damage, in part via oxidative stress and inflammatory responses, which implicates these processes as potential therapeutic approaches. Prior literature has shown that Telmisartan (TEL) may provide protective effects, presumably mediated by its anti-oxidant and anti-inflammatory activities. The purpose of this study was to determine TEL's hepatoprotective effects and to identify its possible curative mechanisms in alcoholic liver disease. A mouse chronic alcohol plus binge feedings model was used in the current study for induction of alcoholic liver disease (ALD). Our results showed that TEL (10 mg/kg/day) has the ability to reduce serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP). TEL also increased the activity of superoxide dismutase (SOD) and glutathione (GSH) with concomitant reduction of nitric oxide (NO) malonaldehyde (MDA) in the liver homogenate. Moreover, TEL downregulated nuclear factor kappa B (NF-κB) expression and decreased liver content of interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α). These anti-inflammatory and anti-oxidant activities were associated with a significant increase in the expression of nuclear factor erythroid 2-related factor 2 (Nrf-2), peroxisome proliferator-activated receptors -γ (PPAR-γ), and heme oxygenase-1 (Hmox-1). In conclusion, TEL's hepatoprotective effects against ALD may be attributable to its anti-inflammatory and anti-oxidant activities which may be in part via the modulation of PPAR-γ/ Nrf-2/ NF-κB crosstalk.

Hepatotoxic potentials of methotrexate: Understanding the possible toxicological molecular mechanisms

Methotrexate (MTX) is one of the most effective and widely used drugs in the management of autoimmune and dermatological diseases. Rheumatoid arthritis and psoriasis patients who are under long term MTX-therapy are at high risk of developing a liver injury. Accumulation of intracellular MTX-polyglutamate (MTX-PG), a metabolite of MTX triggers oxidative stress, inflammation, steatosis, fibrosis, and apoptosis in hepatocytes. MTX-PG causes oxidative stress in the liver by inducing lipid peroxidation thereby releasing reactive oxygen species and suppressing antioxidant response elements. MTX-PG induces several pro-inflammatory signaling pathways and cytokines such as tumor necrosis factor-α, nuclear factor kappa B and interleukin 6 (IL-6), IL- β1, IL-12. MTX-PG depletes hepatic folate level and decreases RNA and DNA synthesis leading to hepatocyte death. MTX-PG inhibits 5-aminoimidazole-4-carboxamide ribonucleotide transformylase enzyme and thereby causes accumulation of intracellular adenosine, which causes activation of hepatic stellate cells, extracellular matrix accumulation and hepatic fibrosis. MTX-PG induces hepatocytes apoptosis by activation of caspase 3 via the intrinsic pathway. Clinically, aggravation of underlying fatty liver to non-alcoholic steatohepatitis with fibrosis seems to be an important mechanism of liver injury in MTX-treated RA patients. Therefore, there is a need for monitoring liver injury in RA, psoriatic and cancer patients with NAFLD and fibrosis risk factors during MTX treatment. This review summarizes the possible molecular mechanism of MTX-induced hepatotoxicity. It may pave the way for early detection of liver injury and develop novel strategies for treating MTX mediated hepatotoxicity.

Empagliflozin and neohesperidin mitigate methotrexate hepatotoxicity via Nrf2/PPARγ/HO-1 signalling initiation and suppression of NF-κB/Keap1/HSP70/caspase-3 axis in rats

Hepatotoxicity is the main adverse effect of methotrexate (MTX), which limits its clinical use and effectiveness. Both empagliflozin (EMPA) and neohesperidin dihydrochalcone (NHD) have promising criteria for suppressing oxidative stress, inflammation and apoptosis. In this current study, we suggested that EMPA and NHD exhibit protective effects against MTX-triggered liver injury, considering N-acetylcysteine (NAC) as a reference standard. In order to inspect our suggestion, An experimental rat model comprising 70 male adult rats (7 groups, 10 rats in each) was implemented to investigate the effects of MTX (20 mg/kg, i.p. once), alone or with EMPA (10 and 30 mg/kg/day, p.o.), NHD (40 and 80 mg/kg/day, p.o.), and NAC (150 mg/kg/day, p.o.) compared to the normal control animals (1%CMC, p.o.). Pre-treatment with EMPA and NHD showed significant attenuation in liver function abnormalities, pathological tissue deteriorations, hepatic oxidative stress parameters, and the level of expression of pro-inflammatory cytokines TNF-α and IL-6. Also, EMPA and NHD showed significant decreases in NF-κB/Keap1/HSP70/caspase-3 and increases in Nrf2/PPARγ/HO-1 expression levels. In addition, EMPA and NHD showed a marked enhancement of the anti-tumour activity of MTX against HepG2 and lung (A549) cancer cells. This research reveals that both EMPA and NHD can inhibit oxidation, inflammatory reactions, and apoptosis in the liver tissues of MTX-treated rats, mainly through Nrf2/PPARγ/HO-1 signalling initiation and suppression of NF-κB/Keap1/HSP70/caspase-3 axis, considered a unique class of drugs that attenuates or at least delays the onset of MTX-induced toxicity and serves as an innovative therapeutic target for future clinical application in humans.

Captopril downregulates expression of Bax/cytochrome C/caspase-3 apoptotic pathway, reduces inflammation, and oxidative stress in cisplatin-induced acute hepatic injury

Cisplatin (Cis) is an effective cancer therapy commonly employed in many therapeutic regimens. However, treatment regimens that contain either a high dose or cumulative doses of Cis could trigger liver damage. A unique study demonstrated that captopril (Cap) protects against Cis-induced liver toxicity, but only some liver function enzymes and some antioxidant enzymes were investigated in that study. Our study aims to elucidate the protective mechanism of Cap against Cis liver toxicity. Acute liver toxicity was induced in rats by injecting a single Cis dose (7.5 mg/kg) in three groups (n = 6). Two groups were pre-treated with low (50 mg/kg) and high (100 mg/kg) Cap doses for one week before Cis injection, and the third group was injected with Cis only. The high Cap dose significantly improved liver function markers (ALT, AST, and ALP) and hepatic tissue pathology. The low Cap dose significantly improved ALP and, to a lesser extent, hepatic tissue pathology. Both Cap doses significantly decreased liver contents of MDA, IL-1β, and cleaved caspase-3; and liver protein expression of TNF-α, Bax, and caspase-3. The high Cap dose significantly increased liver contents of GSH, GPx, CAT, and SOD, and the liver protein expression of Bcl2. Moreover, only the high Cap dose significantly decreased liver IL-6 content and cytochrome C protein expression. Cap did not inhibit the antitumor impact of Cis against HCT116 cancer cells. Therefore, Cap restricts Cis-induced liver toxicity by reducing inflammation and apoptosis and augmenting the antioxidant system.

Serum ceruloplasmin can predict liver fibrosis in hepatitis B virus-infected patients

BACKGROUND

The presence of significant liver fibrosis in hepatitis B virus (HBV)-infected individuals with persistently normal serum alanine aminotransferase (PNALT) levels is a strong indicator for initiating antiviral therapy. Serum ceruloplasmin (CP) is negatively correlated with liver fibrosis in HBV-infected individuals.

AIM

To examine the potential value of serum CP and develop a noninvasive index including CP to assess significant fibrosis among HBV-infected individuals with PNALT.

METHODS

Two hundred and seventy-five HBV-infected individuals with PNALT were retrospectively evaluated. The association between CP and fibrotic stages was statistically analyzed. A predictive index including CP [Ceruloplasmin hepatitis B virus (CPHBV)] was constructed to predict significant fibrosis and compared to previously reported models.

RESULTS

Serum CP had an inverse correlation with liver fibrosis (r = -0.600). Using CP, the areas under the curves (AUCs) to predict significant fibrosis, advanced fibrosis, and cirrhosis were 0.774, 0.812, and 0.853, respectively. The CPHBV model was developed using CP, platelets (PLT), and HBsAg levels to predict significant fibrosis. The AUCs of this model to predict significant fibrosis, advanced fibrosis, and cirrhosis were 0.842, 0.920, and 0.904, respectively. CPHBV was superior to previous models like the aspartate aminotransferase (AST)-to-PLT ratio index, Fibrosis-4 score, gamma-glutamyl transpeptidase-to-PLT ratio, Forn's score, and S-index in predicting significant fibrosis in HBV-infected individuals with PNALT.

CONCLUSION

CPHBV could accurately predict liver fibrosis in HBV-infected individuals with PNALT. Therefore, CPHBV can be a valuable tool for antiviral treatment decisions.

Telmisartan Protects Auditory Hair Cells from Gentamicin-Induced Toxicity in vitro

BACKGROUND

Telmisartan is an angiotensin II receptor blocker that has pleiotropic effects and protective properties in different cell types. Moreover, telmisartan has also shown partial agonism on the peroxisome proliferator-activated receptor γ (PPAR-γ). Auditory hair cells (HCs) express PPAR-γ, and the protective role of PPAR-γ agonists on HCs has been shown.

OBJECTIVES

The objective of this study was to investigate the effects of telmisartan on gentamicin-induced ototoxicity in vitro.

METHODS

Cochlear explants were exposed to gentamicin with or without telmisartan, and/or GW9662, an irreversible PPAR-γ antagonist.

RESULTS

Telmisartan protected auditory HCs against gentamicin-induced ototoxicity. GW9662 completely blocked this protective effect, suggesting that it was mediated by PPAR-γ signaling. Exposure to GW9662 or telmisartan alone was not toxic to auditory HCs.

CONCLUSIONS

We found that telmisartan, via PPAR-γ signaling, protects auditory HCs from gentamicin-induced ototoxicity. Therefore, telmisartan could potentially be used in the future to prevent or treat sensorineural hearing loss.

Protective effects of hesperidin against MTX-induced hepatotoxicity in male albino rats

Hesperidin (HD), a bioflavonoid, has been shown to exert hepatoprotective effects. Our aim is to investigate the possible protective effects of HD against methotrexate (MTX) hepatotoxicity in adult male Sprague-Dawley (SD) rats that were divided into four groups (10 rats/each) and were exposed to MTX with or without HD co-administration for consecutive 28 days. The results showed that HD significantly ameliorated MTX-induced increase in liver enzymes and histopathological changes. Hepatic oxidative stress was suppressed by HD, as evidenced by the decrease in malondialdehyde (MDA), with a concomitant increase in total antioxidant activity (TAC), catalase (CAT), and glutathione (GSH) levels. Moreover, co-administration of HD with MTX remarkably upregulated the expression of Nrf2 and HO-1 compared with the MTX group. By the decrease in nuclear factor-kB (NF-κB) pathway and tumor necrosis factor α (TNF-α), HD obviously attenuated inflammatory response in MTX-lesioned livers. Likewise, the downregulation of P53 by HD could explain its antiapoptotic effects as indicated by increase BCl2 and the significant decrease of caspase-9 mRNA expression as compared with the MTX group. Thus, these findings revealed the hepatoprotective nature of HD against MTX hepatotoxicity by attenuating the pro-inflammatory and apoptotic mediators and improving antioxidant aptitude.

The angiotensin converting enzyme inhibitor captopril attenuates testosterone-induced benign prostatic hyperplasia in rats; a mechanistic approach

Benign prostatic hyperplasia (BPH) is the most widespread urological disorder among elderly men. It is influenced by several factors, among which is the prostatic renin angiotensin system (RAS). Prostatic RAS activates several signaling pathways as proliferation, inflammation and angiogenesis that contribute to BPH development and progression. Captopril is a potent inhibitor of the angiotensin converting enzyme. Therefore, this study was performed to explore the potential protective effect of captopril against testosterone-induced BPH in rats. Male Sprague-Dawley rats were treated with either testosterone (3 mg/kg, s. c.) and/or captopril (100 mg/kg, orally) for four weeks. After treatments, prostatic serum markers and histopathology were assessed. Mechanistically, apoptotic, inflammatory and angiogenic pathways were examined. Testosterone significantly increased prostate weight, prostatic index, prostatic acid phosphatase and prostate specific antigen. These effects were almost prevented by captopril (100 mg/kg). Moreover, testosterone significantly elevated proliferating cell nuclear antigen and reduced Bax/Bcl-2 ratio, p53 and caspase-3 activity. Furthermore, it significantly elevated nuclear factor kappa-B, cyclooxygenase-II, tumor necrosis factor-α and interleukin-8. Besides, it caused a significant rise in vascular endothelial growth factor, basic fibroblast growth factor and matrix metalloproteinase-9. On the contrary, captopril effectively neutralised the proliferative, inflammatory and angiogenic effects of testosterone. Finally, the angiotensin-1 receptor expression in the BPH group was markedly decreased while captopril restored the receptor expression. Collectively, these findings indicate that captopril possesses a potent protective effect against testosterone-induced BPH via inducing apoptotic and suppressing inflammatory and angiogenic signaling pathways.

Effect of Telmisartan in the Oxidative Stress Components Induced by Ischemia Reperfusion in Rats

The therapeutic effects of telmisartan, an angiotensin II receptor antagonist and a peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist, have been demonstrated in several disorders. It has antioxidant and immune response modulator properties and has shown promising results in the treatment of an ischemia/reperfusion (I/R) lesion. In this study, a skeletal muscle (right gastrocnemius muscle) I/R lesion was induced in rats and different reperfusion times (1 h, 24 h, 72 h, 7-day, and 14-day subgroups) were assessed. Furthermore, levels of oxidative markers such as enzymatic scavengers (catalase (CAT) and superoxide dismutase (SOD)) and metabolites (nitrates and 8-oxo-deoxyguanosine) were determined. The degree of tissue injury (total lesioned fibers and inflammatory cell count) was also evaluated. We observed an increase in CAT and SOD expression levels under telmisartan treatment, with a decrease in injury and oxidative biomarker levels in the 72 h, 7-day, and 14-day subgroups. Telmisartan reduced oxidative stress and decreased the damage of the I/R lesion.

Protective Effects of Magnesium Glycyrrhizinate on Methotrexate-Induced Hepatotoxicity and Intestinal Toxicity May Be by Reducing COX-2

Magnesium isoglycyrrhizinate (MgIG), which has been widely employed to treat chronic hepatitis, is synthesized from 18-β glycyrrhizic acid, a main component of traditional Chinese medicine Glycyrrhiza uralensis Fisch. Although the protective effects of MgIG on methotrexate (MTX)-induced liver toxicity have been well-documented, the underlying mechanism remains elusive. MTX was initially used to treat pediatric acute leukemia, and has been widely applied to psoriasis therapy. However, its clinical applications are limited due to hepatotoxicity and intestinal toxicity. Herein, prophylactic administration of MgIG (9 and 18 mg/kg/day) significantly reduced the levels of aspartate aminotransferase and alanine aminotransferase in the serum of rats receiving intravenous injection of MTX (20 mg/kg body weight). MgIG also attenuated MTX-induced hepatic fibrosis. Moreover, it better protected against MTX-induced hepatocyte apoptosis and decreased the serum level of malondialdehyde than reduced glutathione (80 mg/kg/day) did. Interestingly, MTX-induced cyclooxygenase-2 (COX-2) expression, intestinal permeability and inflammation were attenuated after MgIG administration. In addition, MgIG (9 and 18 mg/kg) reduced MTX-induced colocalization of zonula occludens-1 (ZO-1) and connexin 43 (Cx43) in intestinal villi. In conclusion, MgIG exerted beneficial effects on MTX-induced hepatotoxicity and intestinal damage, as a potentially eligible drug for alleviating the hepatic and intestinal side effects of MTX during chemotherapy.

Renin-angiotensin system inhibitor attenuates oxidative stress induced human coronary artery endothelial cell dysfunction via the PI3K/AKT/mTOR pathway

INTRODUCTION

The renin-angiotensin system is associated with blood pressure regulation, inflammation, oxidative stress and insulin resistance. It can decrease intracellular oxidative stress. Stimulation with H₂O₂ leads to increased oxidative stress and activation of the AKT/mTOR pathway. However, the role of renin-angiotensin system inhibitors in oxidative stress-induced endothelial cell dysfunction and H₂O₂-induced AKT activation remains unclear.

MATERIAL AND METHODS

Human coronary artery endothelial cells (HCAECs) were used. The cells were treated with H₂O₂, captopril, the AKT inhibitor MK-2206, and the AKT activator SC79, either separately, or in combination. p53 and ICAM-1 expression, and p-eNOS, p-Akt and mTOR activation were measured by Western blot. Cell viability was assessed by MTT assay. Levels of reactive oxygen species (ROS) were assayed by flow cytometry. Proliferation was monitored by BrdU labeling, while cell migration and invasion were determined by wound healing and Transwell assays, respectively.

RESULTS

The renin-angiotensin system inhibitor captopril reversed H₂O₂-induced oxidative stress and apoptosis in HCAECs. Co-treatment with captopril and the AKT inhibitor MK-2206 reduced the H₂O₂-induced P53 and ICAM-1 protein expression (p < 0.05). The proliferation, migration and invasion of HCAECs were significantly enhanced by co-treatment with captopril and MK-2206 (p < 0.05).

CONCLUSIONS

The study revealed the protective effect of captopril against H₂O₂-induced endothelial cell dysfunction through the AKT/mTOR pathway, and its enhancement of cell survival. These findings provide new insights into the protective effects of captopril and novel therapeutic approaches to treatment of cardiovascular disease.

Management of individuals with chronic hepatitis B virus infection and persistent normal or mildly elevated aminotransferase levels

No consensus exists with respect to positive hepatitis B virus (HBV) DNA results and persistent normal or mildly elevated alanine aminotransferase (ALT). The aim of this study is to investigate the appropriate management and prognosis of these populations with chronic hepatitis B (CHB). A total of 235 subjects with positive HBV DNA results and persistent normal or mildly elevated ALT were enrolled in this study. Liver biopsy and liver stiffness measurements (LSM) were performed in all participants at baseline. Antiviral therapy was initiated in patients with significant hepatic inflammation (G ≥ 2) and/or fibrosis (S ≥ 2). The patients were divided into entecavir and adefovir groups based on HBV DNA load (>2000 IU/mL vs <2000 IU/mL). The liver biopsies were repeated at 72 weeks for the patients received antiviral therapy. We found that 112 subjects were hepatitis B e antigen (HBeAg) positive, and 123 subjects were negative. The corresponding median ALTs were 46 (39.5-52.5) and 48 (41.5-57.0) U/mL, respectively. G ≥ 2 and/or S ≥ 2 diseases were present in 48.8% (82/168) of the HBeAg-positive and 51.2% (86/168) of HBeAg-negative patients, respectively. In addition, 96 HBeAg-positive and 72 HBeAg-negative patients were divided into entecavir and adefovir groups. Meanwhile, liver biopsies had greater diagnostic accuracy for determining cirrhosis than LSM (0.711 vs 1.0, P < 0.0001). At the end of the study period, undetectable HBV DNA levels and normal ALT levels were observed in CHB-infected patients. Furthermore, the patients showed histologic improvement at 72 weeks compared with baseline measurements (G, 1.72 ± 1.00 vs 0.73 ± 0.88, P = 0.0002; S, 1.484 ± 0.90 vs 0.99 ± 1.13, P < 0.0001). Collectively, liver biopsy enhanced diagnostic accuracy for CHB-infected individuals with persistent normal or mildly elevated aminotransferase levels. Moreover, antiviral therapy can improve or regress the hepatic fibrosis and cirrhosis.

Beneficial role of virgin coconut oil supplementation against acute methotrexate chemotherapy-induced oxidative toxicity and inflammation in rats

Background

Methotrexate (MTX) is a commonly used antineoplastic and anti-rheumatoid agent whose efficacy is limited by marked organ toxicities associated with oxidative stress. The study investigated beneficial effect of virgin coconut oil (VCO) supplementation on MTX-induced oxidative stress and inflammation in rats.

Methods

Rats were divided into 4 groups (n = 6): Control, MTX (20 mg/kg bw), VCO (5%) + MTX and VCO (15%) + MTX. The pre-treatment with VCO for 14 days was followed by single intraperitoneal injection of MTX and the rats were sacrificed after 3 days. Serum activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and levels of reduced glutathione (GSH) and malondialdehyde (MDA) were determined. Interleukin-6 (IL-6), C-reactive protein (CRP) and nitric oxide (NO) levels were also evaluated.

Results

MTX induced a distinct diminution in serum activities of oxidative stress markers (SOD, CAT, GPx and GSH), while lipid peroxidation considerably increased demonstrated by MDA level. Similarly, levels of IL-6, CRP and NO increased prominently in MTX control rats. The VCO supplementation markedly enhanced resistance to the MTX-induced biochemical alterations in rats.

Conclusion

VCO can be a useful adjuvant natural product in MTX chemotherapy by reducing oxidative stress and pro-inflammatory responses.