Inducers of cytochrome P450 2E1 enhance methotrexate-induced hepatocytoxicity

Social defeat stress induces liver injury by modulating endoplasmic reticulum stress in C57BL/6J mice

Social defeat stress is associated with endoplasmic reticulum (ER) stress, inflammation and apoptosis. ER stress is thought to contribute to many lifestyle diseases such as liver injury, cardiovascular dysfunction and depression. We investigated the expression of the ER stress markers RNA-dependent protein kinase-like ER kinase (PERK), eukaryotic translation initiation factor 2α (eIF2α) and C/EBP homologous protein (CHOP), as well as inflammatory and apoptotic factors, to assess how social defeat stress induces liver injury. Furthermore, we evaluated the effects of the ER stress inhibitor phenylbutyric acid (PBA) and ER stress inducer thapsigargin (TG) on liver injury. Adult mice were divided into the control, social defeat, social defeat + PBA, TG, PBA and TG + PBA groups. The social defeat and social defeat + PBA groups were simultaneously exposed to social defeat stress for 10 days. The social defeat + PBA, TG, PBA and TG + PBA groups were treated with PBA or TG via intraperitoneal injections. PBA was injected 1 h before the TG injection into the TG + PBA group. Liver samples from six groups of mice were analyzed by histological analysis and western blotting. Social defeat stress promoted ER stress, increased the expression of inflammatory factors and induced apoptosis in the liver of socially defeated mice, which was reversed by PBA. Moreover, ER stress induces TG-induced liver injury by initiating ER stress. Social defeat stress initiates ER stress, promotes the expression of inflammatory and apoptotic factors, and induces liver injury. PBA suppresses liver injury caused by social defeat stress and TG treatment.

Protective Effect of Vitamin D against Hepatic Molecular Apoptosis Caused by a High-Fat Diet in Rats

The protective effects of vitamin D (VitD) in different diseases were studied. The liver is of great interest, especially with the presence of VitD receptors. A high-fat diet (HFD) is associated with many diseases, including liver injury. Consumption of saturated fatty acids triggers hepatic apoptosis and is associated with increased inflammation. We aimed in this study to investigate the protective effects of VitD on hepatic molecular apoptotic changes in response to an HFD in rats. Forty male Wistar albino rats were used and divided into four groups: control, HFD, control + VitD, and VitD-supplemented HFD (HFD + VitD) groups. After six months, the rats were sacrificed, and the livers were removed. RNA was extracted from liver tissues and used for the quantitative real-time RT-PCR of different genes: B-cell lymphoma/leukemia-2 (BCL2), BCL-2-associated X protein (Bax), Fas cell surface death receptor (FAS), FAS ligand (FASL), and tumor necrosis factor α (TNF-α). The results showed that an HFD increased the expression of the pro-apoptotic genes Bax, FAS, and FASL, and reduced the expression of the anti-apoptotic gene BCL2. Interestingly, a VitD-supplemented HFD significantly increased the BCL2 expression and decreased the expression of all pro-apoptotic genes and TNFα. In conclusion, VitD has a protective role against hepatic molecular apoptotic changes in response to an HFD.

Galangin mitigates oxidative stress, inflammation, and apoptosis in a rat model of methotrexate hepatotoxicity

Methotrexate (MTX) is an efficient chemotherapeutic agent for treating various malignancies and autoimmune diseases. However, the long-term use of MTX can result in hepatotoxicity and this limits its use. Galangin (Gal) is a potent flavonoid with various biological activities; however, its protective effect against MTX hepatotoxicity has not been previously investigated. This study evaluated the hepatoprotective of Gal against MTX-induced liver injury. Rats received Gal for 10 days and a single dose of MTX (20 mg/kg) at day 7. The administration of MTX induced liver damage reflected by increased serum biomarkers of liver function and histopathological manifestations. MTX increased hepatic reactive oxygen species (ROS), nitric oxide (NO), malondialdehyde (MDA), and pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), and diminished GSH and antioxidant enzymes. Gal relieved liver injury, ameliorated liver function, oxidative stress, and inflammation markers, and increased antioxidants in MTX-treated rats. In addition, Gal decreased the expression of inflammation and apoptosis markers in MTX-treated rats. In conclusion, Gal possesses a hepatoprotective effect mediated by attenuating oxidative damage, inflammation, and apoptosis in rats.

Toxic mechanisms and pharmacological properties of euptox A, a toxic monomer from A. adenophora

A. adenophora (Spreng.) R.M. King & H. Rob. is as invasive plant known to cause toxicity in humans and animals. The plant's toxic activities have been associated with some toxic phytochemicals present in the plant. One of the major phytochemicals that have been reported to induce toxicity in various organs is euptox A (9-oxo-10, 11-dehydroageraphorone). Previous studies have reported that the main target organs of euptox A are the liver and spleen. Although, many studies have reported on euptox A toxicity in rats and mice, the mechanism of action and the beneficial uses of this toxin as well as it potential uses have not been fully established in literatures. Therefore, this review firstly, aims at elaborating on the toxic effects and mechanism of action of euptox A to give basic knowledge to researchers to help in the development of strategies that will reduce its toxicity to the environment. Secondly, this paper will also report on some beneficial uses of euptox A in recent years as well as suggest some future potential applications of this toxin to help in the utilization of this plant resource.

Effect of Opuntia ficus indica extract on methotrexate-induced testicular injury: a biochemical, docking and histological study

Methotrexate (MTX) is a chemotherapeutic medicine used in the treatment of several types of cancer and inflammatory diseases. It exhibits several drawbacks especially on highly dividing and developing cells. This study aimed to assess the role of Opuntia ficus indica ethanolic extract on testicular damage induced by MTX in rat. MTX was administrated for 10 days (20 mg/kg). Extract of cactus cladodes (Opuntia ficus indica) was given to MTX-treated rats (0.4 g/kg). Spermatozoa were collected from cauda epididymis and analyzed for sperm count and motility. Testis samples were used for histopathological and oxidative stress studies (assessment of malondialdehyde (MDA) levels, protein carbonyls (PCs), catalase (CAT) glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities). Moreover, levels of testosterone were measured in serum by radioimmunoassay. Our results showed that MTX had destructive effects on sperm count and motility associated with significant decrease in testosterone levels in MTX group. This effect was then confirmed by docking results. Testis of MTX group showed increased oxidative stress status. In fact, PCs and MDA were increased and CAT, GPx and SOD were decreased suggesting increased reactive oxygen species and deficiency in enzymatic antioxidant. These findings were associated with disrupted testicular morphology as assessed by histological study. Cladodes extract had protective effects on rat's gonad histology, oxidative stress and improve both sperm parameters (count and motility) and serum testosterone levels. In conclusion, our results suggested that Opuntia ficus indica cladodes extract improved MTX-induced testicular injury and possess potent fertility boosting effects in rats.Communicated by Ramaswamy H. Sarma.

Euptox A Induces G0 /GI arrest and apoptosis of hepatocyte via ROS, mitochondrial dysfunction and caspases-dependent pathways in vivo

As a toxin of Ageratina adenophora (A. adenophora), euptox A (9-oxo-10, 11-dehydroageraphorone) is known to cause hepatotoxicity in animals. In this study, we examined the effects of euptox A on mouse liver cells and its underlying mechanisms for the first time. We found that euptox A induced liver cell cycle arrest and apoptosis in a dose-dependent manner mainly by mitochondria -related pathways, with the affected cells characterized by the appearance of DNA fragmentation, membrane blebbing, and chromatin condensation. The results showed that euptox A similarly induced hepatocyte G0 /GI arrest and apoptosis mainly by ROS accumulation and mitochondria-mediated and caspase-dependent pathways, elucidated by the loss of mitochondrial membrane potential, release of cytochrome C and AIF, activation of caspase-3/-9, Bax, as well as suppression of Bcl-2. This paper will provide new insights into the mechanisms involved in liver toxicity caused by euptox A in mice.

Imbalance of Drug Transporter-CYP450s Interplay by Diabetes and Its Clinical Significance

The pharmacokinetics of a drug is dependent upon the coordinate work of influx transporters, enzymes and efflux transporters (i.e., transporter-enzyme interplay). The transporter-enzyme interplay may occur in liver, kidney and intestine. The influx transporters involving drug transport are organic anion transporting polypeptides (OATPs), peptide transporters (PepTs), organic anion transporters (OATs), monocarboxylate transporters (MCTs) and organic cation transporters (OCTs). The efflux transporters are P-glycoprotein (P-gp), multidrug/toxin extrusions (MATEs), multidrug resistance-associated proteins (MRPs) and breast cancer resistance protein (BCRP). The enzymes related to drug metabolism are mainly cytochrome P450 enzymes (CYP450s) and UDP-glucuronosyltransferases (UGTs). Accumulating evidence has demonstrated that diabetes alters the expression and functions of CYP450s and transporters in a different manner, disordering the transporter-enzyme interplay, in turn affecting the pharmacokinetics of some drugs. We aimed to focus on (1) the imbalance of transporter-CYP450 interplay in the liver, intestine and kidney due to altered expressions of influx transporters (OATPs, OCTs, OATs, PepTs and MCT6), efflux transporters (P-gp, BCRP and MRP2) and CYP450s (CYP3As, CYP1A2, CYP2E1 and CYP2Cs) under diabetic status; (2) the net contributions of these alterations in the expression and functions of transporters and CYP450s to drug disposition, therapeutic efficacy and drug toxicity; (3) application of a physiologically-based pharmacokinetic model in transporter-enzyme interplay.

Therapeutic effect of N-acetylcysteine on chemotherapy-induced liver injury

BACKGROUND

N-acetylcysteine (NAC) may be useful in the management of chemotherapy-induced liver injury.

AIMS

The present study evaluates the possible therapeutic effects of NAC on chemotherapy-induced hepatotoxicity.

METHODS

A total of 102 patients' files who were diagnosed with cancer between 2015 and 2019 were evaluated retrospectively. Two patient groups with and without NAC were selected. NAC was administered in a 3-μg/kg IV dose in a 24-h infusion to 70 patients when any alanine aminotransferase (ALT) or gamma-glutamyl transferase (GGT) values reached three times the normal levels. The other group consisted of 32 patients who were not treated with NAC. Alanine aminotransferase and GGT values were recorded at pretreatment, and on the 1st, 3rd, 5th, and 7th days in both the NAC and non-NAC groups from files.

RESULTS

In the NAC group, ALT and GGT values on day 1, 3, 5, and 7 differed from each other, decreasing from day 1 to day 7. A statistically significant difference was noted between the values in the NAC group (p < 0.001). In the non-NAC group, the ALT values on day 7 were lower than the ALT values on day 1. A comparison of the ALT and GGT values in the NAC and non-NAC groups found that the values in the NAC group decreased earlier than in the non-NAC group.

CONCLUSIONS

This study shows that NAC has a therapeutic effect on hepatotoxicity in children being treated with chemotherapeutic agents due to underlying malign diseases. The early reduction in the results of liver function tests is important for the continuation of chemotherapy.

Adverse effects with intravenous methotrexate in children with acute lymphoblastic leukemia/lymphoma: a retrospective study

Methotrexate (MTX) forms the backbone of maintenance cycles in childhood acute lymphoblastic leukemia (ALL) chemotherapy, including interim maintenance. There is sufficient published data describing toxicities of high dose MTX (HD-MTX), but toxicities with escalating doses of MTX (Capizzi regimen) is not well documented. Capizzi regimen is thought to be relatively safe; we contend that even low escalating doses of MTX have significant toxicities. Our study intends to characterise such events with Capizzi MTX in comparison to that seen with HD-MTX. The retrospective study was conducted at a tertiary care centre of North India. We looked for the presence of six main toxicities: febrile neutropenia, thrombocytopenia, mucositis, hepatic toxicity, renal toxicity and skin toxicity from the clinical records of children with newly diagnosed acute lymphoblastic leukemia and lymphoma (intermediate and high risk disease), treated at our centre from November 2013 to July 2018. Intermediate risk ALL (IR-ALL) received Capizzi MTX, whereas high risk ALL (HR-ALL/T-NHL), received HD-MTX. Both these regimens do not use L-asparaginase. A total of 237 cycles of Capizzi escalating MTX and 151 cycles of HD-MTX (B cell: 3 gm/m² and T cell ALL/T-NHL: 5 gm/m²) during interim maintenance were studied in 93 children. Fifty-four (54) children were of IR (all B cell ALL) and 39 of HR-ALL (21 B-ALL, 18 T-ALL/T-NHL). The combined incidence of toxicities, were similar between the two groups: 68/237 cycles (28.7%) of Capizzi MTX and 45/151 cycles (29.8%) of HD-MTX (P = 0.815). However, mucositis was more commonly witnessed in the later group at 22/151 cycle (14.6%) versus 13/237 cycles (5.5%) in Capizzi MTX (P = 0.002). Nephrotoxicity and skin toxicity was seen only in the HD-MTX group. There was no difference in the severity of toxicity, graded using NCI CTCAE v 5.0, between the two groups. There was no mortality directly attributable to methotrexate toxicity (Grade V toxicity). Serum MTX levels were available in 69/151 (45.7%) cycles of HD-MTX and showed no association with toxicity in this group. Also, there was no difference in the incidence of combined toxicities between groups with (19/69 cycles) or without (26/82 cycles) available serum MTX levels in the HR group (P = 0.577). Male gender, lower baseline ANC and lower BMI had significant association with toxicity. Methotrexate related toxicity is common with both Capizzi and HD-MTX schedule in childhood ALL with a correlation of lower BMI, baseline ANC and male gender. However, it is possible to administer Capizzi as well as HD-MTX in lower middle income countries, with manageable toxicity. Further studies will be required to substantiate our findings and determine the predictors of such events.

Serum Caspase-Cleaved Cytokeratin (M30) Indicates Severity of Liver Dysfunction and Predicts Liver Outcome

BACKGROUND The Model for End-Stage Liver Disease (MELD) score is a well-established tool for assessing hepatic failure. The present retrospective study investigated whether serum keratin 18 (M65) and caspase-cleaved cytokeratin (M30) were associated with liver dysfunction and post-transplant graft failure. MATERIAL AND METHODS A total of 147 patients with liver cirrhosis were categorized into 2 groups according to their baseline MELD score (group I: MELD score <20, n=87, and group II: MELD score ≥20, n=60). Serum M65 and M30 levels were measured by ELISA. RESULTS Cirrhotic patients had significantly higher serum M65 and M30 levels than healthy controls (p<0.0001). Serum M65 was correlated with the MELD score and serum bilirubin (p≤0.007) and serum M30 was correlated with the MELD score, international normalized ratio, and serum bilirubin (p≤0.001). Group II had significantly higher serum M65 and M30 levels than group I (M65, p=0.025 and M30, p<0.001). Patients who lost the allograft during the first post-transplant year had significantly higher serum M30 levels than patients with a graft survival of >1 year (p=0.004). In the regression analysis, serum M30 was associated with the MELD score (odds ratio [OR]=2.545, p=0.005), serum bilirubin (OR=2.605, p=0.005) and 1-year graft loss (OR=3.61, p=0.006). CONCLUSIONS Our data indicate that serum M30 levels reflect the degree of liver dysfunction and can predict 1-year graft loss.

TAT-mediated intracellular delivery of carboxypeptidase G2 protects against methotrexate-induced cell death in HepG2 cells

Side effects of methotrexate (MTX) especially hepatotoxicity limits clinical applications of this anticancer agent. Carboxypeptidase G2 (CPG2) is administrated for the treatment of elevated plasma concentrations of MTX. In this study, we have investigated the intracellular delivery of CPG2 fused to the transactivator transduction domain (TAT) and its protective effects against MTX-induced cell death of HepG2 cells. We have observed that both native and denatured forms of the enzyme transduced into the HepG2 cells efficiently in a concentration and time-dependent manner. The denatured protein transduced with higher efficiency than the native form and was functional inside the cells. MTX exposure significantly decreased HepG2 cell viability in a dose- and time-dependent manner. The cell viability after 24 and 48 h of incubation with 100 μM MTX was reduced to 44.37% and 17.69%, respectively. In cells pretreated with native and denatured TAT-CPG2 protein the cell viability was 98.63% and 86.31% after 24 and 48 h, respectively. Treatment with MTX increased the number of apoptotic HepG2 cells to 90.23% after 48 h. However, the apoptosis percentage in cells pretreated with native and denatured TAT-CPG2 was 21.49% and 22.28%, respectively. Our results showed that TAT-CPG2 significantly prevents MTX-induced oxidative stress by decreasing the formation of ROS and increasing the content of glutathione (GSH) and catalase activity. Our finding indicates that both native and denatured TAT-CPG2 strongly protect HepG2 cells against MTX-induced oxidative stress and apoptosis. Hence, intracellular delivery of CPG2 might provide a new therapeutic strategy for protecting against MTX mediated cytotoxicity.

Diosmin Attenuates Methotrexate-Induced Hepatic, Renal, and Cardiac Injury: A Biochemical and Histopathological Study in Mice

The current study was designed to investigate the beneficial role of diosmin, a biologically active flavonoid, against methotrexate- (MTX-) induced hepatic, renal, and cardiac injuries in mice. Male Swiss albino mice received a single intraperitoneal injection of MTX (at 20 mg/kg, body weight) either alone or in combination with oral diosmin (at 50 or 100 mg/kg body weight, for 10 days). Serum was used to evaluate tissue injury markers, while hepatic, renal, and cardiac tissue samples were obtained for determination of antioxidant activity as well as histopathological examination. Diosmin treatment ameliorated the MTX-induced elevation of serum alkaline phosphatase, aminotransferases, urea, creatinine, lactate dehydrogenase, and creatine kinases as well as plasma proinflammatory cytokines (interleukin-1-beta, interleukin-6, and tumor necrosis factor-alpha). Additionally, both diosmin doses significantly reduced tissue levels of malondialdehyde and nitric oxide and increased those of glutathione, glutathione peroxidase, glutathione reductase, glutathione S-transferase, superoxide dismutase, and catalase, compared to the MTX-intoxicated group. Histopathological examination showed that diosmin significantly minimized the MTX-induced histological alterations and nearly restored the normal architecture of hepatic, renal, and cardiac tissues. Based on these findings, diosmin may be a promising agent for protection against MTX-induced cytotoxicity in patients with cancer and autoimmune diseases.

Pharmacokinetics, pharmacodynamics and pharmacogenetics associated with nonsteroidal anti-inflammatory drugs and opioids in pediatric cancer patients

INTRODUCTION

Advancing appropriate and adequate analgesic pharmacotherapy in pediatric patients with cancer is an area of clinical need. Few studies have been performed to evaluate the selection of an analgesic and appropriate dosing corresponding to analgesic effect among pediatric cancer patients. This review describes information related to pharmacokinetic, pharmacodynamic, and pharmacogenomic (when applicable) considerations for analgesics that are commonly used to manage pain experienced by pediatric patients with cancer. Areas covered: Analgesics commonly used to treat pediatric patients with malignancy patterned after the World Health Organization's 'analgesic ladder' for cancer pain management. Expert opinion: Addressing pain management safely and effectively in pediatric patients with cancer will require advances in both drug development, to increase the armament of analgesics available for children, and our pharmacologic understanding of those analgesics in current use. However, performing the necessary types of studies to develop new analgesics, or gain knowledge of existing therapy, within a population that is relatively small, diverse, and who experience pain originating from a variety of sources, is a tremendous challenge.

The frequency of hepatotoxicity and myelotoxicity in leukemic children with different high doses of methotrexate

Background and objectives

Methotrexate (MTX) is a chemotherapeutic agent that functions as a folic acid antagonist. The frequency of high dose methotrexate (HDMTX)-associated toxicity is variable. In this study, we investigated the frequency of myelotoxicity and hepatotoxicity 7 days after HDMTX infusion.

Patients and methods

This study included children diagnosed with acute lymphoblastic leukemia (ALL) between January 2010 and April 2015. The patient blood counts and biochemical parameters measured before and after 7 days of HDMTX infusion were retrospectively recorded. We assessed HDMTX infusions for 48 children. The number of patients and drug doses included the following: 17 children receiving 1 g/m² (68 infusions), 14 children receiving 2 g/m² (56 infusions), and 17 children receiving 5 g/m² (68 infusions). The classification of toxicity was made based on the Common Terminology Criteria for Adverse Events (CTCAE) 2010 criteria. Myelotoxicity was defined as a hemoglobin level <10 g/L and absolute neutrophil count <1 × 10⁹/L or platelet count <75 × 10⁹/L. The presence of transaminase levels ≥5 times the upper limit was considered to be hepatotoxicity grade ≥3. The MTX levels at 42 h in patients with and without toxicity were compared to evaluate the correlation between MTX levels, hematologic parameters, and transaminase levels.

Results

Myelotoxicity was observed in 35.2%, 37.5%, and 33.8% of the infusions, and hepatotoxicity grade ≥3 was detected in 13.2%, 12.5%, and 11.7% of the infusions in patients receiving 1, 2 and 5 g/m² HDMTX after 7 days, respectively. There was no statistically significant difference between MTX levels at 42 h in patients with and without toxicity (P > .05, for all). There was no correlation between hematologic parameters and transaminase levels and MTX levels at 42 h.

Conclusion

Hematologic toxicity was the most common toxicity observed. The data indicate the hematologic toxicity increased after repeated cycles in patients receiving 5 g/m². However, the hepatic toxicity decreased with additional cycles. Our results show the level of MTX at 42 h is not effective to identify toxicity.

Protective Role of Silymarin on Hepatic and Renal Toxicity Induced by MTX Based Chemotherapy in Children with Acute Lymphoblastic Leukemia

BACKGROUND

ALL is the most common childhood malignancy. The children with ALL are treated with methotrexate (MTX) based chemotherapy protocols. MTX causes unpredictable serious hepatic and renal side effects. Silymarin has antioxidant and anti-inflammatory activities and stimulates tissue regeneration. This study aims to evaluate the protective effects of Silymarin on MTX-based chemotherapy-induced Hepatic and renal toxicity in children with ALL.

PATIENTS AND METHODS

80 children with newly diagnosed ALL were enrolled in the study. They were randomly divided into two groups. Group I included 40 children with ages ranging from 4-13 years and the mean age of 6.85± 2.89 years, who received Silymarin 420 mg/day in 3 divided doses for one week after each MTX dose. Group II included 40 children, with ages ranging from 4-12 years and the mean age of 7.30±2.6 years, who received placebo for one week after MTX therapy. For all patients liver functions including serum bilirubin, total proteins, albumin, globulin and albumin-globulin ratio, alkaline phosphatase, ALT and AST, prothrombin time and activity and renal functions including blood urea and serum creatinine, serum cystatin C and urinary N-acetyl-beta-D-glucosaminidase were done to assess hepatic and renal toxicity before and after chemotherapy.

RESULTS

There were no significant differences between group I and II as regard liver and renal functions before chemotherapy. After chemotherapy, there were significantly higher values of ALT and AST and alkaline phosphatase, and significantly lower Prothrombin activity in group II compared with group I. No significant differences between group I and II were found in total bilirubin, serum protein, and albumin levels. There was significantly lower blood urea, serum creatinine, and cystatin C and urinary N-acetyl-beta-D-glucosaminidase in group I compared with group II.

CONCLUSION

Silymarin improved some hepatic and renal functions in children with ALL who received MTX-based chemotherapy protocols.

RECOMMENDATIONS

Extensive multicenter studies could be recommended to prove the hepatic and renal protective effects of Silymarin in patients with ALL who received MTX-based chemotherapy protocols.

Toward the Definition of the Mechanism of Action of Silymarin: Activities Related to Cellular Protection From Toxic Damage Induced by Chemotherapy

Silymarin, the active extract from milk thistle, has been extensively used in patients with liver disease of different etiology. Although silymarin is a complex of 7 flavonolignans and polyphenols, silibinin is usually regarded as the most active component. In vitro and in vivo studies indicate that silymarin and silibinin protect the liver from oxidative stress and sustained inflammatory processes, mainly driven by Reactive Oxygen Species (ROS) and secondary cytokines. Oxidative stress and inflammation are also involved in cellular damage of many other tissues and their role in the development and toxic reactions in patients receiving cancer therapies is established. The protective effects of silymarin and silibinin, demonstrated in various tissues, suggest a clinical application in cancer patients as an adjunct to established therapies, to prevent or reduce their toxicity. Here we discuss the possible mechanism of the protective action of silymarin and silibinin, focusing on cancer therapies as agents causing cellular damage.

The protective role of G protein-coupled estrogen receptor 1 (GPER-1) on methotrexate-induced nephrotoxicity in human renal epithelium cells

Nephrotoxicity is an important problem during methotrexate (MTX) treatment, which has been widely used for the treatment of several cancer types. Females are less susceptible to kidney diseases; however, the reason for this condition has not to be fully clarified. But sex hormones such as estrogen may have a protective effect on the kidney. We aimed to evaluate the possible protective role of estrogen on the MTX-induced renal epithelial cell death. Primary renal proximal tubular epithelial cells (RPTEC) were incubated with MTX (1, 10 and 100 μM), either alone or in combination with the 17β-estradiol, G protein-coupled estrogen receptor 1 (GPER1) agonist G-1, estrogen receptor alpha agonist propyl pyrazole triol (PPT), estrogen receptor beta agonist diarylpropionitrile (DPN). Cell viability was determined by MTT assays. Interleukin (IL)-1β, IL-6, superoxide dismutase (SOD) and malondialdehyde (MDA) levels were determined in RPTEC. Approximately half of the cell death was observed with 10 μM MTX incubation for 48 h. The cell death was prevented by co-incubating with17β-estradiol, PPT and G-1. MTX was significantly induced IL-1β and IL-6.17β-estradiol, PPT and G-1 significantly decreased effects of MTX. SOD activity was significantly decreased treatment with MTX compared to control group. SOD activity was increased with co-incubation with 17β-estradioland G-1 compared to treatment with MTX. MDA levels significantly increased in treatment with MTX compared with the control group. Increased MDA levels by MTX-induced was decreased significantly by the treatment with 17β-estradiol and G-1. These data indicate that especially 17β-estradiol and G-1 may be useful in preventing undesirable effects of MTX in renal failure.

Mechanisms of Thymoquinone Hepatorenal Protection in Methotrexate-Induced Toxicity in Rats

To investigate mechanisms by which thymoquinone (TQ) can prevent methotrexate- (MTX-) induced hepatorenal toxicity, TQ (10 mg/kg) was administered orally for 10 days. In independent rat groups, MTX hepatorenal toxicity was induced via 20 mg/kg i.p. at the end of day 3 of experiment, with or without TQ. MTX caused deterioration in kidney and liver function, namely, blood urea nitrogen, creatinine, alanine aminotransferase, and aspartate aminotransferase. MTX also caused distortion in renal and hepatic histology, with significant oxidative stress, manifested by decrease in reduced glutathione and catalase, as well as increase in malondialdehyde levels. In addition, MTX caused nitrosative stress manifested by increased nitric oxide, with upregulation of inducible nitric oxide synthase. Furthermore, MTX caused hepatorenal inflammatory effects as shown by increased tumor necrosis factor-α, besides upregulation of necrosis factor-κB and cyclooxygenase-2 expressions. MTX also caused apoptotic effect, as it upregulated caspase 3 in liver and kidney. Using TQ concurrently with MTX restored kidney and liver functions, as well as their normal histology. TQ also reversed oxidative and nitrosative stress, as well as inflammatory and apoptotic signs caused by MTX alone. Thus, TQ may be beneficial adjuvant that confers hepatorenal protection to MTX toxicity via antioxidant, antinitrosative, anti-inflammatory, and antiapoptotic mechanisms.

End-stage methotrexate-related liver disease is rare and associated with features of the metabolic syndrome

BACKGROUND

Methotrexate (MTX) is one of the most frequently prescribed drugs in contemporary medicine with a well-recognised hepatotoxic potential, for which stringent laboratory and histological surveillance has long been advocated.

AIM

To estimate the population burden of end-stage methotrexate-related liver disease (MTX-LD) in the United States and identify independent host risk factors for this disease entity.

METHODS

We analysed the records of all individuals who had been listed for, and/or received, liver transplantation in the United States, as reported to the Organ Procurement and Transplantation Network between 1 October 1987 and 31 December 2011, and identified those whose liver disease was attributed, wholly or partly, to MTX therapy. We also compared the demographic and clinical characteristics of adult individuals with MTX-LD with those listed and/or transplanted for alcoholic liver disease (ALD, n = 43,285), non-alcoholic steatohepatitis (NASH, n = 7569) and primary sclerosing cholangitis (PSC, n = 8526) using the adjusted odds ratios (AORs) derived from multi-variable logistic regression models.

RESULTS

Of 158 904 adults who had been listed for, and/or received, liver transplantation during the study period, only 117 (0.07%) had MTX-LD. Compared with individuals with ALD and PSC, those with MTX-LD were more likely to be older (AORs per 5-year increase: 1.27, P < 0.001 and 1.33, P < 0.001 respectively); female (AORs: 1.78, P = 0.003 and 3.87, P < 0.001); Caucasian (AORs: 3.03, P = 0.001 and 2.05, P = 0.04); and diabetic (AORs: 2.76, P < 0.001 and 4.12, P < 0.001). With the exception of Caucasian ethnicity (AOR: 1.94, P = 0.05), the odds of these characteristics did not differ from individuals with NASH. The odds of elevated body mass index among MTX-LD individuals were higher than those with PSC (AOR per 5 kg/m(2) : 1.51, P < 0.001); similar to those with ALD (AOR per 5 kg/m(2) :1.15, P = 0.1); and lower than those with NASH (AOR per 5 kg/m(2) : 0.66, P < 0.001).

CONCLUSIONS

The United States population burden of end-stage methotrexate-related liver disease is likely to be exceedingly small, suggesting the need for reappraisal of current hepatotoxicity surveillance guidelines. The risk factor profile of methotrexate-related liver disease supports the notion that it may share a common pathogenesis with NASH.

Modulatory effect of silymarin on inflammatory mediators in experimentally induced benign prostatic hyperplasia: emphasis on PTEN, HIF-1α, and NF-κB

The current study aimed to investigate the potential role of the anti-inflammatory effects of silymarin (SIL) in inhibiting experimentally induced benign prostatic hyperplasia (BPH) in rats. Rats were injected testosterone (3 mg/kg/day, subcutaneously (s.c.)) for 2 weeks. In the treatment group, SIL (50 mg/kg, per orally (p.o.)) was administered daily to rats concomitantly with testosterone. Rats were killed 72 h after the last testosterone injection. Then, prostate tissues were dissected out, weighed, and subjected to histological, immunohistochemical, and biochemical examinations. Rats treated with testosterone showed marked increase in prostate weight and prostate weight/body weight with histopathological picture of inflammation and hyperplasia as well as increased collagen deposition. Co-treatment with SIL significantly alleviated these pathological changes. Further, SIL attenuated testosterone-induced nuclear factor-kappa B (NF-κB), cyclooxygenase-II (COX-II), and inducible nitric oxide synthase (iNOS) upregulation, and blunted testosterone-mediated increase in nitric oxide level and messenger RNA (mRNA) expression of interleukin-6 (IL-6) and IL-8. Testosterone-induced downregulation of phosphatase and tensin homolog (PTEN) and upregulation of hypoxia-inducible factor 1α (HIF-1α) were alleviated by SIL. Our findings highlight the anti-inflammatory properties of SIL as a crucial mechanism of its preventive actions against experimental BPH. This can be attributed to, at least partly, attenuating the expression of NF-kB and the subsequent inflammatory cascade, ameliorating the expression of PTEN, and mitigating that of HIF-1α. These data warrant further investigations for the potential use of SIL in the management of BPH.

Alcoholic liver disease: a synopsis of the Charles Lieber's Memorial Symposia 2009-2012

This paper is based upon the 'Charles Lieber Satellite Symposia' organized by Manuela G. Neuman at each of the 2009-2012 Research Society on Alcoholism (RSA) Annual Meetings. The presentations represent a broad spectrum dealing with alcoholic liver disease (ALD). In addition, a literature search (2008-2013) in the discussed area was performed in order to obtain updated data. The presentations are focused on genetic polymorphisms of ethanol metabolizing enzymes and the role of cytochrome P4502E1 (CYP2E1) in ALD. In addition, alcohol-mediated hepatocarcinogenesis, immune response to alcohol and fibrogenesis in alcoholic hepatitis as well as its co-morbidities with chronic viral hepatitis infections in the presence or absence of human deficiency virus are discussed. Finally, emphasis was led on alcohol and drug interactions as well as liver transplantation for end-stage ALD.

Molecular mechanisms of hepatic apoptosis

Apoptosis is a prominent feature of liver diseases. Causative factors such as alcohol, viruses, toxic bile acids, fatty acids, drugs, and immune response, can induce apoptotic cell death via membrane receptors and intracellular stress. Apoptotic signaling network, including membrane death receptor-mediated cascade, reactive oxygen species (ROS) generation, endoplasmic reticulum (ER) stress, lysosomal permeabilization, and mitochondrial dysfunction, is intermixed each other, but one mechanism may dominate at a particular stage. Mechanisms of hepatic apoptosis are complicated by multiple signaling pathways. The progression of liver disease is affected by the balance between apoptotic and antiapoptotic capabilities. Therapeutic options of liver injury are impacted by the clear understanding toward mechanisms of hepatic apoptosis.

Molecular mechanisms of hepatic apoptosis

Apoptosis is a prominent feature of liver diseases. Causative factors such as alcohol, viruses, toxic bile acids, fatty acids, drugs, and immune response, can induce apoptotic cell death via membrane receptors and intracellular stress. Apoptotic signaling network, including membrane death receptor-mediated cascade, reactive oxygen species (ROS) generation, endoplasmic reticulum (ER) stress, lysosomal permeabilization, and mitochondrial dysfunction, is intermixed each other, but one mechanism may dominate at a particular stage. Mechanisms of hepatic apoptosis are complicated by multiple signaling pathways. The progression of liver disease is affected by the balance between apoptotic and antiapoptotic capabilities. Therapeutic options of liver injury are impacted by the clear understanding toward mechanisms of hepatic apoptosis.

The effects of alcohol on the metabolism and toxicology of anti-psoriasis drugs

INTRODUCTION

Alcohol has long been suspected to be a triggering and precipitating factor of psoriasis. Alcohol misuse is common in patients with moderate-to-severe psoriasis and appears to impair treatment outcome.

AREAS COVERED

In this article, the authors review the available data regarding the metabolic and toxicological interactions between anti-psoriasis systemic drugs and ethanol and/or alcoholic beverages. Special attention is given to the influence of alcohol consumption on the hepatotoxic risk of some anti-psoriasis drugs. The article was prepared using a MEDLINE literature search.

EXPERT OPINION

The available knowledge highlights the existence of a few significant pharmacological interactions, such as the reduced exposure to cyclosporine by red wine, the possible increase of cyclosporine levels following a heavy acute alcohol intake, and, especially, the conversion of acitretin to etretinate, in the presence of ethanol, with important implications in females of child-bearing potential. There are limited data on the contributing role of alcohol in the hepatotoxicity induced by some anti-psoriasis drugs and the existing information on this topic is still controversial. However, further investigation is needed to assess the relevance of interactions between alcohol consumption and drug therapy for psoriasis, under both pharmacological and toxicological perspectives. Long-term prospective studies on large cohorts of patients are warranted to disclose the actual significance of such potential interactions in clinical practice.

Role of Grape Seed Extract on Methotrexate Induced Oxidative Stress in Rat Liver

The efficacy of methotrexate (MTX), a widely used cytotoxic chemotherapeutic agent, is often limited by its severe hepatotoxicity. Regarding the mechanisms of these adverse effects, several hypotheses have been put forward, among which oxidative stress is noticeable. The present study was undertaken to determine whether grape seed extract (GSE), a new natural free radical scavenger, could ameliorate the MTX-induced oxidative injury in the rat liver. The animals were divided into 3 groups. Each group consisted of 12 animals. MTX-GSE group: rats were given GSE (100mg/kg body weight) orally for 15 days, and a single dose of MTX (20mg/kg, intraperitoneally) was added on the 10th day. MTX group: these received placebo distilled water (orally) instead of GSE for 15 days and the same MTX protocol applied to this group on the 10th day. Control group: rats were given distilled water (orally) through 15 days and physiological saline (intraperitoneally) instead of MTX was administered on the 10th day in a similar manner. On the 16th day, liver tissue samples were obtained under deep anaesthesia. The level of malondialdehyde (MDA), an end product of lipid peroxidation, and the activities of süperoxide dismutase (SOD) and catalase (CAT), two important endogenous antioxidants, were evaluated in the tissue homogenates. MTX administration increased the MDA level and decreased the SOD and CAT activities in the liver homogenates ( p < 0.001), while these alterations were significantly reversed by GSE treatment ( p < 0.001). MTX led to significantly reduced whole blood count parameters ( p < 0.05). When GSE was supplemented, no significant changes in blood count parameters were noted. It appears that GSE protects the rat liver and inhibits methotrexate-induced oxidative stress. These data indicate that GSE may be of therapeutic benefit when used with MTX.

Beneficial effects of montelukast against methotrexate-induced liver toxicity: a biochemical and histological study

The effects of montelukast against methotrexate-induced liver damage were investigated. 35 Wistar albino female rats were divided into 5 groups as follows: group I: control; group II: montelukast (ML); group III: methotrexate (Mtx); group IV: montelukast treatment after methotrexate application (Mtx + ML); group V: montelukast treatment before methotrexate application (ML + Mtx). At the end of the experiment, the liver tissues of rats were removed. Malondialdehyde (MDA), myeloperoxidase (MPO), and reduced glutathione levels were determined from liver tissues. In addition, the liver tissues were examined histologically. MDA and MPO levels of Mtx group were significantly increased when compared to control group. In Mtx + ML group, these parameters were decreased as compared to Mtx group. Mtx injection exhibited major histological alterations such as eosinophilic staining and swelling of hepatocytes. The glycogen storage in hepatocytes was observed as decreased by periodic acid schiff staining in Mtx group as compared to controls. ML treatment did not completely ameliorate the lesions and milder degenerative alterations as loss of the glycogen content was still present. It was showed that montelukast treatment after methotrexate application could reduce methotrexate-induced experimental liver damage.

Antioxidant peptides from protein hydrolysate of microalgae Navicula incerta and their protective effects in HepG2/CYP2E1 cells induced by ethanol

Marine microalgae have been reported as valuable new sources of pharmacologically active compounds and there are now numerous commercial applications of microalgae. Hence, in this study we evaluated the protective effects of peptides purified from marine microalgae, Navicula incerta, against alcohol-induced damage in HepG2/CYP2E1 cells. To obtain bioactive peptides from microalgae, N. incerta was hydrolysed using various enzymes (alcalase, α-chymotrypsin, neutrase, papain, pepsin, pronase-E and trypsin), and the hydrolysates were evaluated for cytoprotective activity. Among them, papain-derived hydrolysate exhibited higher antioxidant activities than those of other enzymes. Therefore, papain hydrolysate was purified in order to obtain potent antihepatotoxic and antioxidative peptides. The amino acid sequences of the purified peptides were analysed as; NIPP-1 (Pro-Gly-Trp-Asn-Gln-Trp-Phe-Leu) with molecular mass 1 171 Da, and NIPP-2 (Val-Glu-Val-Leu-Pro-Pro-Ala-Glu-Leu) with molecular mass 1108 Da. Furthermore, this study demonstrated that NIPP-1 and NIPP-2 peptides inhibited ethanol-induced cytotoxicity in HepG2/CYP2E1 cells.

Markers of inflammation and fibrosis in alcoholic hepatitis and viral hepatitis C

High levels of profibrinogenic cytokine transforming factor beta (TGF-β), metalloprotease (MMP2), and tissue inhibitor of matrix metalloprotease 1 (TIMP1) contribute to fibrogenesis in hepatitis C virus (HCV) infection and in alcohol-induced liver disease (ALD). The aim of our study was to correlate noninvasive serum markers in ALD and HCV patients with various degrees of inflammation and fibrosis in their biopsies. Methods. Serum cytokines levels in HCV-infected individuals in the presence or absence of ALD were measured. Student's-t-test with Bonferroni correction determined the significance between the groups. Results. Both tumor-necrosis-factor- (TNF)-α and TGF-β levels increased significantly with the severity of inflammation and fibrosis. TGF-β levels increased significantly in ALD patients versus the HCV patients. Proinflammatory cytokines' responses to viral and/or toxic injury differed with the severity of liver inflammation. A combination of these markers was useful in predicting and diagnosing the stages of inflammation and fibrosis in HCV and ALD. Conclusion. Therapeutic monitoring of TGF-β and metalloproteases provides important insights into fibrosis.

Effect of rifampin on production of inflammatory mediators in HepG2 liver epithelial cells

Rifampin, a potent antibacterial agent, is one of the main drugs used in the treatment of mycobacterial infections. Hepatotoxicity is a well-documented adverse event. The aim of this study was to investigate the effect of rifampin on the production of inflammatory mediators in human epithelial HepG2 liver cells in the absence or presence of proinflammatory cytokines. Incubation of HepG2 cells with a cytokine mix plus rifampin was associated with a significant dose-dependent increase in the production of nitric oxide compared to incubation with the cytokine mix alone (P < 0.05) as well as with an increase in inducible nitric oxide synthase protein and mRNA expression. Rifampin significantly increased the secretion of interleukin 8 (IL-8) in both untreated cells (P < 0.001) and cytokine-treated cells (P < 0.006). An array screening assay revealed that rifampin stimulated the production of IL-1β and gamma interferon-induced protein-10 (IP-10) in untreated cells and increased the secretion of RANTES in cytokine-treated cells. Together, these results indicate that rifampin may exert proinflammatory effects on liver cells.

Role of ursodeoxycholic acid in prevention of methotrexate-induced liver toxicity

AIM

Methotrexate (MTX)-induced hepatotoxicity restricts the clinical use of this immunosuppressive drug. In this study, our aim was to research the role of oxidative stress in the hepatic toxicity of MTX and the protective effect of ursodeoxycholic acid (UDCA) in this setting.

METHODS

Wistar type rats (n = 32) were divided into four groups; group-1 as the MTX + UDCA, group-2 as the MTX, group-3 as the UDCA, group-4 as the saline-receiving groups. The MTX + UDCA and MTX groups of rats received 50 mg/kg of UDCA administered orally; whilst physiological saline was administered orally to the MTX and saline groups and continued for the next 6 days. On the second day of the study, the MTX + UDCA and MTX groups had a single intraperitoneal dose of MTX of 20 mg/kg. The UDCA and saline groups also received similar volumes of physiological saline intraperitoneally. On the sixth day, serum samples were collected and analyzed for ALT, alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (GGT) and homogenated liver tissues were examined for reactive oxygen metabolites (ROM); luminol, lucigenin, lipid peroxygenation product malondialdehyde (MDA) and glutathione (GSH) levels.

RESULTS

In the MTX group, serum ALT, ALP, GGT and tissue ROM levels were higher and GSH level was lower. On the histopathological examination, hepatocellular necrosis was clearly more evident in the MTX group than the MTX + UDCA group.

CONCLUSIONS

UDCA treatment protects against MTX-induced liver toxicity. Histopathologically hepatocyte necrosis can be prevented by UDCA treatment, indicating clearly the hepatoprotective effect of this agent on MTX-induced liver injury.

Senecio latifolius induces in vitro hepatocytotoxicity in a human cell lineThis article is one of a selection of papers published in this special issue (part 2 of 2) on the Safety and Efficacy of Natural Health Products

The objectives of this study were twofold: (i) to determine the mechanism(s) of Senecio -induced toxicity in human hepatoblastoma cells (HepG2) in vitro and whether such toxicity could be prevented using N-acetyl-cysteine (NAC), and (ii) to evaluate whether caspases are involved in Senecio-induced apoptosis. Cells were treated with aqueous extracts of Senecio (10 mg·mL–1) with and without NAC. Cytotoxicity was determined by using the MTT assay. Total glutathione (GSH) was measured by using the Tietze assay. Cells were also treated with aqueous extracts of Senecio in the presence or absence of 50 μmol/L caspase-3 inhibitor (IDN) for 24 h. Apoptosis was determined by transmission electron microscopy, and DNA fragmentation was determined by ELISA and terminal dUTP nick-end labelling (TUNEL). Senecio produced cytotoxicity and depleted GSH in a concentration- and time-dependent manner. A significant depletion in GSH was observed after 15 min (p < 0.001 vs. control), whereas significant cytotoxicity was only observed after 3 h (p < 0.001 vs. control). Treatment with NAC prevented Senecio-induced GSH depletion and resulted in a significant decrease in Senecio-induced cytotoxicity (p < 0.001 vs. NAC-untreated cells). Treatment with Senecio for 24 h resulted in 22% ± 2.5% (p < 0.001) apoptosis (vs. control). Pretreatment with 50 μmol caspase inhibitor reduced Senecio-induced apoptosis significantly (vs. non-exposed to IDN) (12% ± 1.5%; p < 0.05). Our results suggest the mechanism of Senecio-induced cytotoxicity in HepG2 cells in vitro involves depletion of cellular GSH. Cytotoxicity is reduced by supplementation with NAC, which thus prevents GSH depletion. Caspase activation is involved in Senecio-induced apoptosis.

Psoriasis patients with diabetes type 2 are at high risk of developing liver fibrosis during methotrexate treatment

BACKGROUND/AIMS

We investigated the impact of diabetes mellitus type 2, overweight, alcohol over-consumption, and chronic hepatitis B or C as risk factors, for liver fibrosis in psoriasis patients treated with methotrexate.

METHODS

One hundred and sixty-nine liver biopsies from 71 patients who underwent liver biopsies as part of the monitoring of methotrexate treatment for psoriasis were reviewed. Fibrosis, steatosis and inflammation were staged according to the NAFLD activity score.

RESULTS

Twenty-six patients had one or more of the risk factors and 25 (96%) of these (median cumulative dose methotrexate 1500 mg) developed liver fibrosis. Of those without risk factor, 26 (58%) (p=0.012) developed fibrosis (median cumulative dose methotrexate 2100 mg). Ten (38%) of the patients with risk factor(s) had severe fibrosis (stage 3-4) (mean cumulative dose methotrexate 1600 mg), while four (9%) (p=0.0012) of those without risk factors had severe fibrosis (median cumulative dose methotrexate 1900 mg).

CONCLUSIONS

Patients with methotrexate treated psoriasis and risk factors for liver disease, especially diabetes type 2 or overweight, are at higher risk of developing severe liver fibrosis compared to those without such risk factors, even when lower cumulative methotrexate doses are given.

An updated systematic review of the pharmacology of silymarin

BACKGROUND

Recent years have seen an explosion of scientific papers that deal with drugs from the fruits of milk thistle and its active substances silymarin (standardized mixture of flavonolignanes), thus justifying an updated systematic review.

METHODS

Electronic databases identified silymarin, silibinin, silicristin or milk thistle as descriptors in >700 papers (34% published in last 5 years; 92% dealt with animal pharmacological). Only papers adequately reporting on experimental conditions, dosing, variables tested and statistics were analysed.

RESULTS

Silymarin was found to modify specifically the functions related to various transporters and receptors located in the cell membranes; that is, organic anion uptake transporter peptides (OATP), ABC transporters (P-gp), bile salt export pump, as well as TNF-alpha-dependent and possibly selectin-dependent phenomena. In the cytoplasm, some antioxidant properties and the inhibition of the lipoxygenase pathway seem quite selective and could concur to the antitoxic effects. Some effects like the inhibition of inducible nitric-oxide synthase, of nuclear factor kappa B, and reduction of collagen synthesis are indicative of DNA/RNA-mediated effects. Several studies using 'in vitro' and 'in vivo' cancer models suggest a potential of silymarin in such diseases. Topical and systemic silymarin has skin protective properties against UV-induced damage in epidermis and causes an up-regulation of tumour-suppressor genes p53- and p21CIP1. There were no data on hepatic viral replication, viremia or spontaneous tumours in the data examined.

CONCLUSIONS

Data presented here do not solve the question about the complex mechanism(s) of action of the medicinal herbal drug silymarin. Silymarin may be a natural multi-functional and multi-target drug.

L-Carnitine ameliorates methotrexate-induced oxidative organ injury and inhibits leukocyte death

Methotrexate (MTX), a folic acid antagonist widely used for the treatment of a variety of tumors and inflammatory diseases, affects normal tissues that have a high rate of proliferation, including the hematopoietic cells of the bone marrow and the gastrointestinal mucosal cells. To elucidate the role of free radicals and leukocytes in MTX-induced oxidative organ damage and the putative protective effect of L-carnitine (L-Car), Wistar albino rats were administered a single dose of MTX (20 mg/kg) followed by either saline or L-Car (500 mg/kg) for 5 days. After decapitation of the rats, trunk blood was obtained, and the ileum, liver, and kidney were removed for histological examination and for the measurement of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity, and collagen content. Our results showed that MTX administration increased the MDA and MPO activities and collagen content and decreased GSH levels in all tissues, while these alterations were reversed in L-Car-treated group. The elevated serum TNF-alpha level observed following MTX treatment was depressed with L-Car. The oxidative burst of neutrophils stimulated by Annexin V was reduced in the saline-treated MTX group, while L-Car abolished this inhibition. Similarly, flow cytometric measurements revealed that leukocyte apoptosis was increased in MTX-treated animals, while L-Car reversed these effects. Severe degeneration of the intestinal mucosa, liver parenchyma, and glomerular and tubular epithelium observed in the saline-treated MTX group was improved by L-Car treatment. These results suggest that L-Car, possibly via its free radical scavenging and antioxidant properties, ameliorates MTX-induced oxidative organ injury and inhibits leukocyte apoptosis. Thus, supplementation with L-Carnitine as an adjuvant therapy may be promising in alleviating the systemic side-effects of chemotherapeutics.

β-glucan ameliorates methotrexate-induced oxidative organ injury via its antioxidant and immunomodulatory effects

Methotrexate is an antifolate that is widely used in the treatment of rheumatic disorders and malignant tumors. The efficacy of methotrexate is often limited by severe side effects and toxic sequelae, where oxidative stress is noticeable. In the present study, the possible protective effect of beta-glucan in methotrexate-induced toxicity was investigated. Following a single dose of methotrexate injection (20 mg/kg), either saline or beta-glucan (50 mg/kg; orally) was administered for 5 days. After decapitation of the rats, trunk blood was obtained and the ileum, liver and kidney were removed to measure tissue malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content, as well as histological examination. Methotrexate caused a significant decrease in GSH levels, while MDA levels, MPO activity and collagen content were increased in all the tissues (P<0.05-0.001). On the other hand, administration of beta-glucan following methotrexate abolished the depletion of GSH and inhibited the increases in MDA, MPO activity and collagen content, while the histological analysis revealed that beta-glucan attenuated the tissue damage. Stimulation index, an indicator of oxidative burst in the neutrophils, was decreased by methotrexate (P<0.001), while beta-glucan abolished this effect. Furthermore, increased leukocyte apoptosis and cell death in methotrexate-treated animals were inhibited by beta-glucan (P<0.05). Thus, the findings of the present study suggest that beta-glucan, through its antioxidant and immunoregulatory effects, may be of therapeutic value in alleviating the leukocyte apoptosis, oxidative tissue injury and thereby the intestinal and hepatorenal side effects of methotrexate treatment.

The Activities of Antioxidant Enzymes and the Level of Malondialdehyde in Cerebellum of Rats Subjected to Methotrexate: Protective Effect of Caffeic Acid Phenethyl Ester

Methotrexate (MTX), a folic acid antagonist, is widely used as a cytotoxic chemotherapeutic agent. MTX-associated neurotoxicity is an important clinical problem. The aim of this study was to investigate the role of caffeic acid phenethyl ester (CAPE) on cerebellar oxidative stress induced by MTX in rats. A total of 19 adult male rats were divided into three experimental groups as follows: MTX group (MTX treated), MTX+CAPE group (MTX+CAPE treated), and control group. MTX was administered intraperitoneally (i.p.) with a single dose of 20 mg kg(-1) on the second day of experiment. CAPE was administered i.p. with a dose of 10 micromol kg(-1) day(-1) for 7 days. Malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD) and catalase (CAT) were determined in cerebellar tissue of rats. MTX caused to significant increase in MDA levels (an important marker of lipid peroxidation) in the MTX group compared with the controls (p = 0.006). CAPE significantly reduced the MTX induced lipid peroxidation in the MTX+CAPE group compared to the MTX (p = 0.007). The activities of SOD and CAT were significantly increased in the MTX group when compared with the control group (p = 0.0001, p = 0.004, respectively). The increased activities of these enzymes were significantly reduced by CAPE treatment (p = 0.004, p = 0.034, respectively). As a result, CAPE may protect from oxidative damage caused by MTX treatment in rat cerebellum.

Taurine protects against methotrexate-induced toxicity and inhibits leukocyte death

The efficacy of methotrexate (MTX), a widely used cytotoxic chemotherapeutic agent, is often limited by severe side effects and toxic sequelae. Regarding the mechanisms of these side effects, several hypotheses have been put forward, among which oxidative stress is noticeable. The present study was undertaken to determine whether taurine, a potent free radical scavenger, could ameliorate MTX-induced oxidative injury and modulate immune response. Following a single dose of methotrexate (20 mg/kg), either saline or taurine (50 mg/kg) was administered for 5 days. After decapitation of the rats, trunk blood was obtained and the ileum, liver, and kidney were removed to measure malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity, and collagen content, as well as histological examination. Our results showed that MTX administration increased the MDA, MPO activity, and collagen contents and decreased GSH levels in all tissues (P < 0.001), while these alterations were reversed in taurine-treated group (P < 0.05-0.01). Elevated (P < 0.001) TNF-alpha level observed following MTX treatment was depressed with taurine (P < 0.01). Oxidative burst of neutrophils stimulated by phorbol myristate acetate was reduced in saline-treated MTX group (P < 0.001), while taurine abolished this effect. Similarly, flow cytometric measurements revealed that leukocyte apoptosis and cell death were increased in MTX-treated animals, while taurine reversed these effects (P < 0.05). Reduced cellularity in bone marrow samples of MTX-treated group (P < 0.01) was reversed back to control levels in taurine-treated rats. Severe degeneration of the intestinal mucosa, liver parenchyma, glomerular, and tubular epithelium observed in saline-treated group was improved by taurine treatment. In conclusion, it appears that taurine protects against methotrexate-induced oxidant organ injury and inhibits leukocyte apoptosis and may be of therapeutic potential in alleviating the systemic side effects of chemotherapeutics.

Silymarin treatment of viral hepatitis: a systematic review

Silymarin from the milk thistle herb (Silybum marianum) is used by many patients with chronic viral hepatitis, but its efficacy remains unknown. We performed a systematic review of silymarin for the treatment of chronic viral hepatitis B and C. An exhaustive search strategy identified 148 papers that studied silymarin compounds in liver disease. Of these, four trials included patients with hepatitis C, one included hepatitis B patients, and two, unspecified chronic viral hepatitis. However, only one trial exclusively studied patients with hepatitis C, and none involved patients with only hepatitis B. Silymarin treatment resulted in a decrease in serum transaminases compared with baseline in four studies, and compared with placebo in only one study. There is no evidence that silymarin affects viral load or improves liver histology in hepatitis B or C. No studies were found that investigated the use of silymarin concomitantly with interferon, nucleoside analogues, or other conventional treatments for hepatitis B or C. In conclusion, silymarin compounds likely decrease serum transaminases in patients with chronic viral hepatitis, but do not appear to affect viral load or liver histology. Nevertheless it may be worthwhile to determine its effects in conjunction with standard antiviral treatment.

Paediatric cancer pain management using the WHO analgesic ladder--results of a prospective analysis from 2265 treatment days during a quality improvement study

OBJECTIVE

To collect data on pain management in paediatric oncology with respect to the WHO ladder approach. SETTING, DESIGN, PATIENTS AND METHODS: Eight German tertiary care paediatric oncology centres prospectively documented all their in-patient pain treatment courses from June 1999 to December 2000. Pain was scored using a 1-6 faces scale.

RESULTS

Two hundred and twenty four patients (median age, 9 years; range 0.2-32.1) were enrolled. Three hundred and thirty three pain episodes comprising a total of 2265 treatment days were documented. Pain was mostly therapy associated. The most frequently administered non-opioid analgesics were dipyrone and paracetamol. On WHO step 2, tramadol was almost the only opioid used. During tramadol monotherapy average daily pain scores were lower than with a combination of tramadol and non-opioid analgesics. On WHO step 3, morphine was at least part of the analgesic regimen on most treatment days. Strong opioids were combined with a non-opioid analgesic on 41% of the treatment days. The mean intravenous morphine equivalence dose was 0.034 mg/kg/h. During opioid and non-opioid combination therapy, adverse effects were more frequent, and average pain scored higher than on opioid monotherapy.

CONCLUSIONS

WHO-guidelines were closely followed in Germany and seem to provide effective analgesia for children with cancer pain. In our patient group there is no evidence that a combination of an opioid with a non-opioid is more effective than opioid therapy alone in in-patient paediatric oncology pain treatment.

The activities of purine-catabolizing enzymes and the level of nitric oxide in rat kidneys subjected to methotrexate: Protective effect of caffeic acid phenethyl ester

The aim of this experimental study was to investigate the possible role of nitric oxide (NO) levels, and activities of adenosine deaminase (ADA) and xanthine oxidase (XO) in the pathogenesis of methotrexate-induced nephrotoxicity, and was the effect of caffeic acid phenethyl ester (CAPE), the potent free radical scavenger, in decreasing the toxicity. A total of 19 adult male rats were divided into three experimental groups, as follows: control group, MTX-treated group, and MTX+CAPE treated group. MTX were administered intraperitoneally (i.p.) with 20 mg/kg for single dose. CAPE was administered i.p. with a dose of 10 micromol//kg once daily for 7 days. The injection of MTX induced a significant increase in the activities of ADA and XO, and NO levels in renal tissue of rats (p < 0.0001). Co-treatment with CAPE caused a significantly decrease activities of ADA and XO, and the levels of NO in renal tissue (p < 0.0001). The results of this study revealed that NO, XO and ADA may play an important role in the pathogenesis of MTX-induced oxidative renal damage. CAPE may have protective potential in this process and it will become a promising drug in the prevention of this undesired side effect of MTX.

Glycogen Synthase Kinase-3 Mediates Acetaminophen-Induced Apoptosis in Human Hepatoma Cells

The mild analgesic drug acetaminophen (AAP) induces severe hepatic injury when taken at excessive doses. Recent evidence shows that the initial form of damage is through apoptosis, but this fails to go to completion and degenerates into necrosis. The aim of this study was to elucidate the mechanism through which AAP induces apoptosis using human HuH7 hepatoma cells as an in vitro model system to investigate the initial phase of AAP-induced hepatic injury. AAP-induced apoptosis in HuH7 cells as evidenced by chromatin condensation was preceded by the translocation of Bax to mitochondria and the cytoplasmic release of the proapoptotic factors cytochrome c and Smac/DIABLO. A concomitant loss of mitochondrial membrane potential occurred. Activation of the mitochondrial pathway of apoptosis led to the activation of execution caspases-3 and -7. AAP-induced apoptosis and cell death was blocked by inhibitors of caspases but not by inhibitors of calpains, cathepsins, and serine proteases. Apoptosis was unaffected by inhibitors of the mitochondrial permeability transition pore and by inhibitors of Jun NH(2)-terminal kinases, p38 mitogen-activated protein kinase, or mitogen-activated protein kinase kinase 1/2. However, pharmacological inhibition of glycogen synthase kinase-3 (GSK-3) delayed and decreased the extent of AAP-induced apoptosis. In comparison, endoplasmic reticulum stress-induced but not prooxidant-induced apoptosis of HuH7 cells was sensitive to GSK-3 inhibition. It is concluded that AAP-induced apoptosis involves the mitochondrial pathway of apoptosis that is mediated by GSK-3 and most likely initiated through an endoplasmic reticulum stress response.

Methotrexate induction of human sulfotransferases in Hep G2 and Caco-2 cells

Methotrexate (MTX) was the first antifolate drug developed for the treatment of cancer. It is also effective in treating inflammatory and autoimmune diseases. Sulfotransferases are phase II drug-metabolizing enzymes and their induction by hormones and endogenous molecules is relatively well known, although xenobiotic drug induction of sulfotransferases has not been well studied. In the present investigation, MTX is shown to be a xenobiotic inducer of human sulfotransferases in transformed human liver (Hep G2) and intestinal (Caco-2) cells. Following MTX treatment, various sulfotransferases were induced in both cell lines. Enzyme assay, Western blot and reverse-transcription polymerase chain reaction (RT-PCR) results demonstrated that protein and mRNA expressions of human simple phenol sulfotransferase (P-PST), human monoamine sulfotransferase (M-PST), human dehydroepiandrosterone sulfotransferase (DHEA-ST) and human estrogen sulfotransferase (EST) were induced in Hep G2 cells; M-PST and DHEA-ST were induced in Caco-2 cells. Inductions in both cell lines were dose dependent. Enzyme activity and Western blot results were in good agreement with RT-PCR results, suggesting that the induction is at the gene transcription level. Folic acid had a significantly lesser effect on sulfotransferases compared with MTX. Interestingly, the induction of different sulfotransferases by MTX was inhibited by high doses of folic acid at both protein and mRNA levels in Hep G2 cells. Methotrexate is the first antifolate and apoptosis-inducing drug to show induction of sulfotransferases in Hep G2 cells and Caco-2 cells. The inhibition by folic acid suggests a possible mechanism for MTX induction.

Herbal and complementary medicine in dermatology

This article is a description of how I have integrated Complementary Medicine into the practice of dermatology over the past 2 decades. It emphasizes observing the principles of the system being used, such as the herbal concept of the synergy of the entire plant extract. Examples discussed include the use of flavonoids to protect the liver and capillaries. Herbs and techniques for reducing the inflammatory response, as well as for enhancing immunity, are given. The concept of homeopathy and a few remedies to use in office practice are discussed. Finally, a few methods to complement the treatment of melanoma are presented.