Chronic morphine treatment induces oxidant and apoptotic damage in the mice liver

A multi-target ligand (JM-20) prevents morphine-induced hyperalgesia in naïve and neuropathic rats

The present study examines the possible inhibitory effect of JM-20, a multi-target neuroprotective compound, on the development of morphine-induced hyperalgesia in Male Sprague-Dawley naïve rats. Additionally, the impact of JM-20 on chronic constriction injury (CCI) rats under chronic morphine exposure was investigated, and its efficacy in reducing mechanical hypersensitivity and histopathological changes in the sciatic nerve was assessed. JM-20 (20 mg/kg, per os [p.o.]), administered 60 min before morphine (10 mg/kg, s.c. twice daily at 12 h intervals) for ten days, significantly inhibited the development of morphine-induced hyperalgesia assessed using an electronic pressure-meter paw test, hot-plate, and formalin test, as well as the appearance of spontaneous withdrawal somatic symptoms in rats. Furthermore, JM-20 decreases spinal pro-inflammatory interleukin-1β and restores glutathione to close physiological concentrations, biomarkers directly related to the intensity of mechanical hypernociception. After CCI and sham surgery, co-treatment with JM-20 (10 mg/kg, p.o.) for five days decreased morphine increased-mechanical hypersensitivity, even 12 days after its discontinuation. Continued morphine treatment imposed a neuroinflammatory challenge in CCI animals, further increasing cellularity (>75% immune cell infiltration) with lymphocytes and macrophages. However, JM-20 co-treatment still reduced the presence of cellular infiltrates (51-75%) with a predominance of lymphocytes. Even in the absence of nerve injury, JM-20 attenuated the peripheral neuroinflammatory response observed in morphine-treated sham-operated animals (0% vs. 1-25%). These findings suggest that JM-20 could prevent morphine-induced hyperalgesia by anti-inflammatory and antioxidant mechanisms.

Activation of the Keap1/Nrf2 Pathway as an Adaptive Response to an Electrophilic Metabolite of Morphine

Morphinone (MO) is an electrophilic metabolite of morphine that covalently binds to protein thiols via its α,β-unsaturated carbonyl group, resulting in toxicity in vitro and in vivo. Our previous studies identified a variety of redox signaling pathways that are activated during electrophilic stress. Here, we examined in vitro activation of a signaling pathway involving Kelch-like ECH-associated protein 1 (Keap1) and nuclear factor erythroid 2-related factor 2 (Nrf2) in response to MO. Exposure of HepG2 cells to MO caused covalent modification of Keap1 thiols (evaluated using biotin-PEAC₅-maleimide labeling) and nuclear translocation of Nrf2, thereby up-regulating downstream genes encoding ATP binding cassette subfamily C member 2, solute carrier family 7 member 11, glutamate-cysteine ligase catalytic subunit, glutamate-cysteine ligase modifier subunit, glutathione S-transferase alpha 1, and heme oxygenase 1. However, dihydromorphinone, a metabolite of morphine lacking the reactive C7-C8 double bond, had little effect on Nrf2 activation. These results suggest that covalent modification is crucial in the Keap1/Nrf2 pathway activation and that this pathway is a redox signaling-associated adaptive response to MO metabolism.

Assessment of Neurotoxic Effects of Oxycodone and Naloxone in SH-SY5Y Cell Line

Opioid drugs have analgesic properties used to treat chronic and post-surgical pain due to descending pain modulation. The use of opioids is often associated with adverse effects or clinical issues. This study aimed to evaluate the toxicity of opioids by exposing the neuroblastoma cell line (SH-SY5Y) to 0, 1, 10, and 100 µM oxycodone and naloxone for 24 h. Analyses were carried out to evaluate cell cytotoxicity, identification of cell death, DNA damage, superoxide dismutase (SOD), glutathione S-transferase (GST), and acetylcholinesterase (AChE) activities, in addition to molecular docking. Oxycodone and naloxone exposure did not alter the SH-SY5Y cell viability. The exposure to 100 µM oxycodone and naloxone significantly increased the cells' DNA damage score compared to the control group. Naloxone exposure significantly inhibited AChE, GST, and SOD activities, while oxycodone did not alter these enzymes' activities. Molecular docking showed that naloxone and oxycodone interact with different amino acids in the studied enzymes, which may explain the differences in enzymatic inhibition. Naloxone altered the antioxidant defenses of SH-SY5Y cells, which may have caused DNA damage 24 h after the exposure. On the other hand, more studies are necessary to explain how oxycodone causes DNA damage.

Oxidative Stress and Extracellular Matrix Remodeling Are Signature Pathways of Extracellular Vesicles Released upon Morphine Exposure on Human Brain Microvascular Endothelial Cells

Morphine, a commonly used antinociceptive drug in hospitals, is known to cross the blood-brain barrier (BBB) by first passing through brain endothelial cells. Despite its pain-relieving effect, morphine also has detrimental effects, such as the potential induction of redox imbalance in the brain. However, there is still insufficient evidence of these effects on the brain, particularly on the brain endothelial cells and the extracellular vesicles that they naturally release. Indeed, extracellular vesicles (EVs) are nanosized bioparticles produced by almost all cell types and are currently thought to reflect the physiological state of their parent cells. These vesicles have emerged as a promising source of biomarkers by indicating the functional or dysfunctional state of their parent cells and, thus, allowing a better understanding of the biological processes involved in an adverse state. However, there is very little information on the morphine effect on human brain microvascular endothelial cells (HBMECs), and even less on their released EVs. Therefore, the current study aimed at unraveling the detrimental mechanisms of morphine exposure (at 1, 10, 25, 50 and 100 µM) for 24 h on human brain microvascular endothelial cells as well as on their associated EVs. Isolation of EVs was carried out using an affinity-based method. Several orthogonal techniques (NTA, western blotting and proteomics analysis) were used to validate the EVs enrichment, quality and concentration. Data-independent mass spectrometry (DIA-MS)-based proteomics was applied in order to analyze the proteome modulations induced by morphine on HBMECs and EVs. We were able to quantify almost 5500 proteins in HBMECs and 1500 proteins in EVs, of which 256 and 148, respectively, were found to be differentially expressed in at least one condition. Pathway enrichment analysis revealed that the "cell adhesion and extracellular matrix remodeling" process and the "HIF1 pathway", a pathway related to oxidative stress responses, were significantly modulated upon morphine exposure in HBMECs and EVs. Altogether, the combination of proteomics and bioinformatics findings highlighted shared pathways between HBMECs exposed to morphine and their released EVs. These results put forward molecular signatures of morphine-induced toxicity in HBMECs that were also carried by EVs. Therefore, EVs could potentially be regarded as a useful tool to investigate brain endothelial cells dysfunction, and to a different extent, the BBB dysfunction in patient circulation using these "signature pathways".

Characteristics of opioid prescribing to outpatients with chronic liver diseases: A call for action

Background

Chronic liver disease (CLD) is among the strongest risk factors for adverse prescription opioid-related events. Yet, the current prevalence and factors associated with high-risk opioid prescribing in patients with chronic liver disease (CLD) remain unclear, making it challenging to address opioid safety in this population. Therefore, we aimed to characterize opioid prescribing patterns among patients with CLD.

Methods

This retrospective cohort study included patients with CLD identified at a single medical center and followed for one year from 10/1/2015-9/30/2016. Multivariable, multinomial regression was used identify the patient characteristics, including demographics, medical conditions, and liver-related factors, that were associated with opioid prescriptions and high-risk prescriptions (≥90mg morphine equivalents per day [MME/day] or co-prescribed with benzodiazepines).

Results

Nearly half (47%) of 12,425 patients with CLD were prescribed opioids over a one-year period, with 17% of these receiving high-risk prescriptions. The baseline factors significantly associated with high-risk opioid prescriptions included female gender (adjusted incident rate ratio, AIRR = 1.32, 95% CI = 1.14–1.53), Medicaid insurance (AIRR = 1.68, 95% CI = 1.36–2.06), cirrhosis (AIRR = 1.22, 95% CI = 1.04–1.43) and baseline chronic pain (AIRR = 3.40, 95% CI = 2.94–4.01), depression (AIRR = 1.93, 95% CI = 1.60–2.32), anxiety (AIRR = 1.84, 95% CI = 1.53–2.22), substance use disorder (AIRR = 2.16, 95% CI = 1.67–2.79), and Charlson comorbidity score (AIRR = 1.27, 95% CI = 1.22–1.32). Non-alcoholic fatty liver disease was associated with decreased high-risk opioid prescriptions (AIRR = 0.56, 95% CI = 0.47–0.66).

Conclusion

Opioid medications continue to be prescribed to nearly half of patients with CLD, despite efforts to curtail opioid prescribing due to known adverse events in this population.

Melatonin attenuates morphine-induced conditioned place preference in Wistar rats

PURPOSE

Morphine is the predominantly used drug for postoperative and cancer pain management. However, the abuse potential of morphine is the primary disadvantage of using opioids in pain management. Melatonin is a neurohormone synthesized in the pineal gland and is involved in circadian rhythms in mammals, as well as other physiological functions. Melatonin provenly attenuates alcohol-seeking and relapse behaviors in rats. Therefore, we aimed to investigate the involvement of the melatonergic system in attenuating morphine dependence.

MATERIALS AND METHODS

Male Wistar rats were divided into three groups: control, morphine, and morphine + melatonin. Animals were habituated for 3 days, and the initial preference was evaluated. Following the initial preference, the control group received the vehicle and was placed for a 45-min session in the assigned chamber every day, alternating between the two chambers, for 8 days. The morphine group received a morphine injection (5 mg/kg, IP) and was placed for a 45-min session in the white chamber, for a total of four sessions. The morphine + melatonin group received the morphine injection (5 mg/kg, IP) for a total of four sessions over an 8-day period. In the posttest session, the control and morphine groups received a vehicle injection 30 min before placement in the conditioned place preference (CPP). The morphine + melatonin group received a single injection of melatonin (50 mg/kg, IP) 30 min before the preference test.

RESULTS

Statistical analysis revealed that repeated administration of morphine for four sessions produced a significant increase in the CPP score in the morphine group compared to the control group. However, a single melatonin injection administered 30 min before the posttest attenuated morphine-seeking behavior and reduced morphine-induced place preference.

CONCLUSION

These findings provide novel evidence for the role of the melatonergic system as a potential target in modulating morphine-seeking behavior.

Codeine exerts cardiorenal injury via upregulation of adenine deaminase/xanthine oxidase and caspase 3 signaling

AIMS

Codeine treatment has been shown to be associated with glucolipid deregulation, though data reporting this are inconsistent and the mechanisms are not well understood. Perturbation of glutathione-dependent antioxidant defense and adenosine deaminase (ADA)/xanthine oxidase (XO) signaling has been implicated in the pathogenesis of cardiometabolic disorders. We thus, hypothesized that depletion of glutathione contents and upregulation of ADA/XO are involved in codeine-induced glucolipid deregulation. The present study also investigated whether or not codeine administration would induce genotoxicity and apoptosis in cardiac and renal tissues.

MATERIALS AND METHODS

Male New Zealand rabbits received per os distilled water or codeine, either in low dose (4 mg/kg) or high dose (10 mg/kg) for 6 weeks.

KEY FINDINGS

Codeine treatment led to reduced absolute and relative cardiac and renal mass independent of body weight change, increased blood glucose, total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL-C), as well as increased atherogenic indices and triglyceride-glucose index (TyG). Codeine administration significantly increased markers of cardiac and renal injury, as well as impaired cardiorenal functions. Codeine treatment also resulted in increased cardiac and renal malondialdehyde, Advanced Glycation Endproducts (AGE) and 8-hydroxydeoxyguanosine (8-OH-dG), and myeloperoxidase (MPO), ADA, XO, and caspase 3 activities. These observations were accompanied by impaired activities of cardiac and renal proton pumps.

SIGNIFICANCE

Findings of this study demonstrate that upregulation of ADA/XO and caspase 3 signaling are, at least partly, contributory to the glucolipid deregulation and cardiorenal injury induced by codeine.

Morphine may act via DDX49 to inhibit hepatocellular carcinoma cell growth

Pain in hepatocellular carcinoma (HCC) is a frequent cause of low quality of life, and morphine is routinely used as a first-line opiate analgesic in HCC. Morphine may exert not only analgesic effects but also anti-cancer effects via unknown mechanisms. Here we show that morphine can inhibit HCC cell proliferation. We further show that DEAD-box helicase 49 (DDX49) is up-regulated in HCC tumors, and that knocking down the DDX49 gene decreases tumor formation in vivo and in vitro, as well as reduces tumor metastasis in vivo. Morphine decreases DDX49 expression in HCC cells. Our results suggest that DDX49 contributes to HCC, and that morphine may exert anti-cancer effects by down-regulating it.

Heroin use is associated with liver fibrosis in the Miami Adult Studies on HIV (MASH) cohort

BACKGROUND

People who use opioids and people living with HIV (PLWH) are at increased risk for liver-related morbidity and mortality. Although animal models suggest that chronic opioid use may cause liver damage, research in humans is limited. We aimed to determine whether opioid use, particularly heroin, was associated with liver fibrosis.

METHODS

Cross-sectional analysis of 679 participants (295 HIV/HCV uninfected, 218 HIV mono-infected, 87 HCV mono-infected, 79 HIV/HCV coinfected) from the Miami Adult Studies on HIV (MASH) cohort. Liver fibrosis was assessed via magnetic resonance elastography (MRE) on a 3 T Siemens MAGNETOM Prisma scanner.

RESULTS

A total of 120 (17.7 %) participants used opioids. Liver fibrosis was present in 99 (14.6 %) participants and advanced liver fibrosis in 31 (4.6 %). Heroin use (N = 46, 6.8 %) was associated with HCV-seropositivity, smoking, misuse of prescription opioids, and polysubstance use. The use of heroin, but not misuse of prescription opioids, was significantly associated with liver fibrosis (OR = 2.77, 95 % CI: 1.18-6.50) compared to heroin non-users, after adjustment for confounders including excessive alcohol consumption, polysubstance use and HIV and HCV infections. Both HIV and HCV infections were associated with liver fibrosis, whether virally suppressed/undetectable or viremic.

CONCLUSIONS

Heroin use was independently associated with increased risk for liver fibrosis irrespective of the use of other substances and HIV or HCV infections. Both HIV and HCV were associated with higher risk for liver fibrosis, even among those with suppressed or undetectable viral loads. The exact mechanisms for opioid-induced liver fibrosis remain to be fully elucidated.

Mesoporous Polydopamine Nanoparticles Attenuate Morphine Tolerance in Neuropathic Pain Rats by Inhibition of Oxidative Stress and Restoration of the Endogenous Antioxidant System

Oxidative stress resulting from reactive oxygen species (ROS) is known to play a key role in numerous neurological disorders, including neuropathic pain. Morphine is one of the commonly used opioids for pain management. However, long-term administration of morphine results in morphine antinociceptive tolerance (MAT) through elevation of ROS and suppression of natural antioxidant defense mechanisms. Recently, mesoporous polydopamine (MPDA) nanoparticles (NPS) have been known to possess strong antioxidant properties. We speculated that morphine delivery through an antioxidant nanocarrier might be a reasonable strategy to alleviate MAT. MPDAs showed a high drug loading efficiency of ∼50%, which was much higher than conventional NPS. Spectral and in vitro studies suggest a superior ROS scavenging ability of NPS. Results from a rat neuropathic pain model demonstrate that MPDA-loaded morphine (MPDA@Mor) is efficient in minimizing MAT with prolonged analgesic effect and suppression of pro-inflammatory cytokines. Additionally, serum levels of liver enzymes and levels of endogenous antioxidants were measured in the liver. Treatment with free morphine resulted in elevated levels of liver enzymes and significantly lowered the activities of endogenous antioxidant enzymes in comparison with the control and MPDA@Mor-treated group. Histopathological examination of the liver revealed that MPDA@Mor can significantly reduce the hepatotoxic effects of morphine. Taken together, our current work will provide an important insight into the development of safe and effective nano-antioxidant platforms for neuropathic pain management.

Evaluation of male infertility treatment following Rhus coriaria extract administration on rats exposed to morphine

Morphine is the most common analgesic drug that is widely used in post-operative interventions. This drug causes free radical accumulation leading to spermatogenesis failure. Antioxidant agents like Sumach (Rhus coriaria) neutralize cellular free radicals. In this study, the properties of antioxidative, modulative of inflammatory cytokines, and apoptotic genes following Sumach extract administration on morphine-induced fertility destruction in male Wistar rats was evaluated. Sixty-four animals were grouped (n = 8) including; 1: control, 2: morphine, 3-5: Sumach (200, 400, 800 mg/kg), and 6-8: morphine + Sumach. Hydroalcoholic extract of Sumach seeds was prepared. Treatments with Sumach extract were applied orally and intraperitoneally daily for 8 weeks. The P53, Bcl2 and caspase-3 genes expression were measured by real-time PCR. Cytokines involved in inflammation were evaluated by ELISA. Sperm parameters, total antioxidant capacity (TAC), testosterone, and germinal layer height (GLH) were assessed. All parameters (investigated in this study) in Morphine group reduced significantly than the control group (P ˂ 0.01) (except P53 and caspase-3 genes expression and inflammatory cytokine which were improved). All factors in Sumach and Sumach + Morphine groups were significantly enhanced compared to the Morphine group (P ˂ 0.01) (except P53 and caspase-3 genes expression and inflammatory cytokine which were declined). Morphine disrupted the physiological function of male fertility system. Besides, all doses of Sumach showed no therapeutic changes compared to the control group. Sumach with anti-infertility features compensates the toxic effect of Morphine administration.

Repeated Administration of Clinical Doses of Tramadol and Tapentadol Causes Hepato- and Nephrotoxic Effects in Wistar Rats

Tramadol and tapentadol are fully synthetic and extensively used analgesic opioids, presenting enhanced therapeutic and safety profiles as compared with their peers. However, reports of adverse reactions, intoxications and fatalities have been increasing. Information regarding the molecular, biochemical, and histological alterations underlying their toxicological potential is missing, particularly for tapentadol, owing to its more recent market authorization. Considering the paramount importance of liver and kidney for the metabolism and excretion of both opioids, these organs are especially susceptible to toxicological damage. In the present study, we aimed to characterize the putative hepatic and renal deleterious effects of repeated exposure to therapeutic doses of tramadol and tapentadol, using an in vivo animal model. Male Wistar rats were randomly divided into six experimental groups, composed of six animals each, which received daily single intraperitoneal injections of 10, 25 or 50 mg/kg tramadol or tapentadol (a low, standard analgesic dose, an intermediate dose and the maximum recommended daily dose, respectively). An additional control group was injected with normal saline. Following 14 consecutive days of administration, serum, urine and liver and kidney tissue samples were processed for biochemical, metabolic and histological analysis. Repeated administration of therapeutic doses of both opioids led to: (i) increased lipid and protein oxidation in liver and kidney, as well as to decreased total liver antioxidant capacity; (ii) decreased serum albumin, urea, butyrylcholinesterase and complement C3 and C4 levels, denoting liver synthesis impairment; (iii) elevated serum activity of liver enzymes, such as alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and γ-glutamyl transpeptidase, as well as lipid profile alterations, also reflecting hepatobiliary commitment; (iv) derangement of iron metabolism, as shown through increases in serum iron, ferritin, haptoglobin and heme oxygenase-1 levels. In turn, elevated serum cystatin C, decreased urine creatinine output and increased urine microalbumin levels were detected upon exposure to tapentadol only, while increased serum amylase and urine N-acetyl-β-D-glucosaminidase activities were observed for both opioids. Collectively, these results are compatible with kidney injury. Changes were also found in the expression levels of liver- and kidney-specific toxicity biomarker genes, upon exposure to tramadol and tapentadol, correlating well with alterations in lipid profile, iron metabolism and glomerular and tubular function. Histopathological analysis evidenced sinusoidal dilatation, microsteatosis, mononuclear cell infiltrates, glomerular and tubular disorganization, and increased Bowman's spaces. Although some findings are more pronounced upon tapentadol exposure, our study shows that, when compared with acute exposure, prolonged administration of both opioids smooths the differences between their toxicological effects, and that these occur at lower doses within the therapeutic range.

Proteomic analysis of protein composition of rat hippocampus exposed to morphine for 10 days; comparison with animals after 20 days of morphine withdrawal

Opioid addiction is recognized as a chronic relapsing brain disease resulting from repeated exposure to opioid drugs. Cellular and molecular mechanisms underlying the ability of organism to return back to the physiological norm after cessation of drug supply are not fully understood. The aim of this work was to extend our previous studies of morphine-induced alteration of rat forebrain cortex protein composition to the hippocampus. Rats were exposed to morphine for 10 days and sacrificed 24 h (groups +M10 and −M10) or 20 days after the last dose of morphine (groups +M10/−M20 and −M10/−M20). The six altered proteins (≥2-fold) were identified in group (+M10) when compared with group (−M10) by two-dimensional fluorescence difference gel electrophoresis (2D-DIGE). The number of differentially expressed proteins was increased to thirteen after 20 days of the drug withdrawal. Noticeably, the altered level of α-synuclein, β-synuclein, α-enolase and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was also determined in both (±M10) and (±M10/−M20) samples of hippocampus. Immunoblot analysis of 2D gels by specific antibodies oriented against α/β-synucleins and GAPDH confirmed the data obtained by 2D-DIGE analysis. Label-free quantification identified nineteen differentially expressed proteins in group (+M10) when compared with group (−M10). After 20 days of morphine withdrawal (±M10/−M20), the number of altered proteins was increased to twenty. We conclude that the morphine-induced alteration of protein composition in rat hippocampus after cessation of drug supply proceeds in a different manner when compared with the forebrain cortex. In forebrain cortex, the total number of altered proteins was decreased after 20 days without morphine, whilst in hippocampus, it was increased.

Evaluating the Effects of Chronic Administration of Natural Honey on the Development of Dependence on Morphine in the Male Rats

Background: According to the previous studies, the exact mechanism of dependence on opioids and withdrawal syndrome has not been fully understood but one of the most important mechanisms is the increase of pro-inflammatory cytokines in CNS. On the other way, previous studies showed that natural honey (NHO) has anti-inflammatory properties. This study was aimed to evaluate the effects of chronic administration of natural honey on the development of morphine dependence in male rats. Methods: Honey was prepared from Tarom Oliya region in Zanjan province. Experiments were performed on male Wistar rats weighing 225-275 g, randomly divided into 6 groups (n=8). The study groups included morphine group, the three doses of morphine plus honey group (at doses of 200,400 and 800 mg/kg, i.p.), the morphine plus vehicle group, and the saline group. The subcutaneous injections of additive doses of morphine were used for 9 days to create morphine dependency. On the 9th day, one hour after the morning dose of morphine, naloxone (4 mg/kg, i.p.) was injected, and symptoms of withdrawal syndrome were assessed for 60 minutes. Then, blood samples were taken to measure TNF-α. One-way ANOVA and Tukey tests were used to compare the results. P- Value of <0.05 was considered as statistically significant. Results: The results of this study showed that intraperitoneal injection of honey at 3 doses (200, 400 and 800 mg/kg with p <0.001) could significantly decrease the total score of the symptoms compared to the morphine-vehicle control group. Natural honey (NHO) could significantly decrease TNF-α at dose of 400 mg/kg. Conclusion: The results indicated that chronic administration of NHO had beneficial effects in reducing symptoms of morphine withdrawal syndrome, and this effect is probably due to the anti-inflammatory effect caused by the polyphenolic compounds in honey.<br />

Protective Effect of Morphine Against the Oxidant-Induced Injury in H9c2 Cells

There are some indications that morphine may exert myocardial protective effects under certain conditions. The aim of the present study was to investigate the effect of morphine on viability and oxidative state of H9c2 cells (rat cardiomyoblasts) influenced by oxidative stress that was elicited by exposure to tert-butyl hydroperoxide (t-BHP). Our experiments showed that pretreatment with morphine before the addition of t-BHP markedly improved cell viability. Morphine was able to increase total antioxidant capacity of H9c2 cells and to reduce the production of reactive oxygen species, protein carbonylation, and lipid peroxidation. Cellular damage caused by t-BHP was associated with low levels of p38 MAPK and GSK-3β phosphorylation. Pretreatment with morphine augmented p38 phosphorylation, and the increased phospho-p38/p38 ratio was preserved even in the presence of t-BHP. Morphine did not change the level of GSK-3β phosphorylation, but interestingly, the phospho-GSK-3β/GSK-3β ratio significantly increased after subsequent incubation with t-BHP. Furthermore, morphine exposure resulted in upregulation of the antioxidant enzyme catalase. The protective effect of morphine was abrogated by the addition of the PI3K inhibitor wortmannin and/or p38 MAPK inhibitor SB203580. It can be concluded that morphine may protect H9c2 cells against oxidative stress and that this protection is at least partially mediated through activation of the p38 MAPK and PI3K/GSK-3β pathways.

Iranian crack induces hepatic injury through mitogen-activated protein kinase pathway in the liver of Wistar rat

Objectives

Iranian crack (IC) is a heroin-based substance manifesting various pathologic side effects. Herein, we aimed to investigate the mechanism of IC-induced liver injuries in Wistar rats.

Materials and Methods

Twenty male Wistar rats were randomly divided into two groups: control, and IC (0.9 mg/kg/day/IP, for 30 days). Mitochondrial reactive oxygen species (ROS) production was measured by DCF fluorescence staining. The expression of tumor necrosis factor-alpha (TNF-α), interleukin 1β (IL-1β), and phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK) and c-Jun N-terminal kinase (c-JNK) were assessed by immunoblotting assay. The intensity of collagen fiber in the liver was also determined by Trichrome-Masson staining. Furthermore, serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) activities were measured using colorimetric methods.

Results

Our results showed that ROS production, p38 MAPK, c-JNK phosphorylation levels, and expression of TNF-α and IL-1β were significantly elevated in the liver tissue of IC group as compared to the control group. Moreover, collagen fiber and ALT activity were increased in the liver tissue of IC group compared to the control group. However, there was no statistically significant difference in the levels of ALP between two groups. In addition, there was a positive correlation between the intensity of collagen fiber and the ALT activity, and the levels of TNF-α and IL-1β and liver enzymes activities including ALP, ALT, and AST.

Conclusion

Our findings revealed that IC-induced liver cells injury is partially mediated by MAPK stress kinases. Therefore, regular liver examination in substance abuse is strongly recommended.

Postoperative local incision analgesia for acute pain treatment in patients with hepatocellular carcinoma

OBJECTIVE

The present study aimed to investigate the analgesic effect and safety of using local incision analgesia to treat acute postoperative pain in patients with hepatocellular carcinoma (HCC).

METHOD

A cohort of 60 patients undergoing liver cancer resection was randomly divided into three groups (n=20 per group): local incision analgesia (LIA) group, which received local infiltration with ropivacaine combined with a postoperative analgesia pump; intravenous patient-controlled analgesia (PCA) group, which received fentanyl intravenous analgesia postoperatively; and the control group, which received tramadol hydrochloride injection postoperatively according to the NRS scoring system. The postoperative analgesic effect in each group was compared and tumor recurrence (survival) was analyzed using the Kaplan-Meier method.

RESULTS

NRS scores, rate of analgesic usage, ambulation time (h) and intestinal function recovery time (h) were significantly reduced in LIA group compared with the control group at each postoperative time point (6, 12, 24 and 48 hours; p<0.05). Additionally, the NRS scores of LIA patients at 12 hours post-surgery was significantly reduced compared with PCA group (p<0.05), and the occurrence of postoperative adverse events in LIA group was significantly lower than that in PCA group (p<0.05). Survival analysis demonstrated that the mean survival time (tumor recurrence) was significantly increased in LIA group compared with the control group (χ2=4.749; p=0.029).

CONCLUSION

Local incision analgesia improves the analgesic effect, causes fewer adverse reactions and increases postoperative survival time. Our study demonstrated that local incision analgesia is a safe and effective method of postoperative pain management following hepatectomy.

The Impact of Opium Consumption on Blood Glucose, Serum Lipids and Blood Pressure, and Related Mechanisms

Aim: Substance abuse has become a universal crisis in our modern age. Among illegal substances, opium and its derivatives have been ranked second in terms of usage after cannabis in the world. In many Asian regions, the use of opium enjoys a high social acceptance; hence, some common people and even medical practitioners believe that opium lowers blood glucose and pressure and treat dyslipidemia. How much this belief is scientifically justified?

Method: The results of available studies on both humans and animals searched in different search engines up to mid-2016 were integrated (78 articles). Upon the findings we try to offer a more transparent picture of the effects of opium on the mentioned factors along with the probable underlying mechanisms of its action.

Results: Taken together, a variety of evidences suggest that the consumption of opium has no scientific justification for amendment of these biochemical variables. The mechanisms proposed so far for the action of opium in the three above disorders are summarized at the end of the article. Short term effects seems to be mostly mediated through central nervous system (neural and hormonal mechanisms), but long term effects are often due to the structural and functional alterations in some body organs.

Conclusion: Although opium may temporarily reduce blood pressure, but it increases blood glucose and most of blood lipids. Moreover its long term use has negative impacts and thus it aggravates diabetes, dyslipidemia and hypertension. Accordingly, it is necessary to inform societies about the potential disadvantages of unauthorized opium consumption.

Opioids and Viral Infections: A Double-Edged Sword

Opioids and their receptors have received remarkable attention because they have the ability to alter immune function, which affects disease progression. In vitro and in vivo findings as well as observations in humans indicate that opioids and their receptors positively or negatively affect viral replication and virus-mediated pathology. The present study reviews recent insights in the role of opioids and their receptors in viral infections and discusses possible therapeutic opportunities. This review supports the emerging concept that opioids and their receptors have both favorable and unfavorable effects on viral disease, depending on the type of virus. Targeting of the opioid system is a potential option for developing effective therapies; however caution is required in relation to the beneficial functions of opioid systems.

Beneficial effects of Bacopa monnieri extract on opioid induced toxicity

The present study examined the hepatotoxicity and nephrotoxicity of morphine and illicit street heroin and their amelioration by a standardized methanolic extract of Bacopa monnieri (L.) (mBME) in rats. Morphine or street heroin was administered at a dose of 20 mg/kg for 14 and 21 days. mBME (40 mg/kg) or ascorbic acid (50 mg/kg) was administered two hours before morphine or street heroin. High performance liquid chromatography (HPLC) was used for the standardization of bacoside-A major components in mBME. The antioxidant potential of mBME was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Administration of morphine and street heroin resulted in marked elevation of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and creatinine. Histopathological changes induced by morphine and street heroin after 14 days were of reversible nature while treatment for 21 days was associated with irreversible changes. Pretreatment with mBME or ascorbic acid restored the elevation of serum ALT, AST and creatinine and protected liver and kidneys from the toxicological influence of morphine and street heroin. HPLC analysis showed that mBME contained bacoside-A major components i.e. bacoside-A₃ (37.5 μg/mg), bacopaside-II (4.62 μg/mg) and bacopasaponin-C (1.91 μg/mg). The EC₅₀ for the DPPH free radical scavenging assay revealed that mBME possessed strong antioxidant potential. These results concluded that as compared to morphine, street heroin was associated with severe biochemical and histopathological changes in the liver and kidneys. Bacopa monnieri having strong antioxidant potential may provide a beneficial herbal remedy for the efficient management of opioid related hepatotoxicity and nephrotoxicity.

Comparative study of in vitro prooxidative properties and genotoxicity induced by aflatoxin B1 and its laccase-mediated detoxification products

In this paper, the enzymatic detoxification of aflatoxin B1 (AFB1) by laccase was studied, and the prooxidant properties and mutagenicity of the detoxification products were compared with those of AFB1. The optimal enzymatic reaction occurred in 0.1M of citrate buffer containing 20% DMSO at 35 °C, a pH of 4.5, and a laccase activity of 30 U mL(-1). After 2 d, sixty-seven percent of the toxic substrate was removed. The prooxidative properties of the detoxified products (27% versus 86%) and the mutagenicity were significantly decreased in comparison with the parent toxin. Unlike AFB1, which promoted metabolism-dependent genetic mutations by base-pair substitution, the detoxified products did not induce genotoxicity. Comparison of the Km values for AFB1 and riboflavin, a valuable food nutrient, indicated that laccase showed greater affinity for the toxin than for riboflavin.

Opioid use and risk of liver fibrosis in HIV/hepatitis C virus-coinfected patients in Canada

OBJECTIVES

Opioid use and opioid-related mortality have increased dramatically since the 1990s in North America. The effect of opioids on the liver is incompletely understood. Some studies have suggested that opioids cause liver damage and others have failed to show any harm. HIV/hepatitis C virus (HCV)-coinfected persons may be particularly vulnerable to factors increasing liver fibrosis. We aimed to describe opioid use in an HIV/HCV-coinfected population in Canada and to estimate the association between opioid use and liver fibrosis.

METHODS

We conducted a cross-sectional descriptive analysis of the Canadian Co-infection Cohort Study data to characterize opioid use. We then conducted a longitudinal analysis to assess the average change in aspartate aminotransferase-to-platelet ratio index (APRI) score associated with opioid use using a generalized estimating equation with linear regression. We assessed the progression to significant liver fibrosis (APRI ≥ 1.5) associated with opioid use with pooled logistic regression.

RESULTS

In the 6 months preceding cohort entry, 32% of the participants had received an opioid prescription, 28% had used opioids illicitly and 18% had both received a prescription and used opioids illicitly. Neither prescribed nor illicit opioid use was associated with a change in the median APRI score [exp(β) 0.99 (95% confidence interval (CI) 0.82, 1.12) and exp(β) 0.95 (95% CI 0.81, 1.10), respectively] or with faster progression to liver fibrosis [hazard odds ratio (HOR) 1.20 (95% CI 0.73, 1.67) and HOR 1.09 (95% CI 0.63, 1.55), respectively].

CONCLUSIONS

Although opioids were commonly used both legally and illegally in our cohort, we were unable to demonstrate a negative impact on liver fibrosis progression.

The effect of various morphine weaning regimens on the sequelae of opioid tolerance involving physical dependency, anxiety and hippocampus cell neurodegeneration in rats

Chronic consumption of morphine induces physical dependency, anxiety, and neurodegeneration. In this study, morphine on its own has been used for the management of morphine-induced dependency, oxidative stress, and apoptosis. Forty-eight male rats were randomly divided into six groups. Rats in groups 1-5 were made morphine dependent by an increasing manner of morphine for 7 days (15-45 mg/kg). For the next 14 days, morphine was administered using the following regimen: (i) once daily 45 mg/kg (positive controls), (ii) the same dose at additional intervals (6 h longer than the previous intervals each time), (iii) 45 mg/kg of morphine at irregular intervals like of 12, 24, 36 h, (iv) decreasing dose once daily (every time 2.5 mg/kg less than the former dosage). Group 5 received 45 mg/kg of morphine and 10 mg/kg of SOD mimetic agent (M40401) injection per day. Group 6 (negative control) received saline solution only. On day 22, all animals received naloxone (3 mg/kg) and their Total Withdrawal Index (TWI) and blood cortisol levels were measured. After drug treatment, hippocampus cells were isolated, and oxidative, antioxidative, and apoptotic factors were evaluated. Various regimens of morphine reduced TWI, cortisol levels, Bax activity, caspase-3, caspase-9, TNF-α, and IL-1β and lipid peroxidation. In all treatment groups, GSH level, superoxide dismutase, glutathione peroxidase, and Bcl-2 activity were significantly increased. Furthermore, SOD mimetic agent c diminished morphine effect on SOD activity. Thus, varying the dosage regimen of morphine can reduce the severity of morphine-induced dependency and neurodegeneration.

Efficacy of postoperative continuous wound infiltration with local anesthesia after open hepatectomy

Objectives:

Local anesthetic wound infiltration is widely used as an effective adjunct during multimodal postoperative pain management. The aim of this study was to evaluate the effectiveness of continuous wound infusion of ropivacaine in postoperative pain relief, opioid sparing, incidence of nausea and vomiting, and bowel and liver function improvement in patients undergoing open hepatectomy.

Methods:

Forty patients undergoing open hepatectomy were enrolled in this prospective, randomized, double-blinded, placebo-controlled trial. Patients were divided into 2 groups: the 0.9% saline continuous infusion group (the control group; n=20) and the ropivacaine continuous infusion group (the Ropi group; n=20). Outcomes measured postoperatively were pain score at rest and on movement, sufentanil consumption, incidence of nausea and vomiting, and sedation score across 48 postoperative hours. Time to bowel recovery, liver function change, mean length of hospitalization, patient satisfaction, and other data after 48 postoperative hours were collected until hospital discharge.

Results:

Pain scores at rest were lower for the ropivacaine group and reached significance after 8 and 16 hours (P<0.01). Sufentanil consumption (41.50±21.80 vs. 89.70±35.22 μg; P<0.01) after 48 hours, time to bowel recovery (1.80±0.70 vs. 3.15±1.04 d; P<0.01), incidence of nausea and vomiting (1.75±0.72 vs. 2.40±0.68; P<0.05), and mean length of hospitalization (5.6±2.44 vs. 7.35±2.85 d; P<0.01) were significantly reduced, and the sedation score and liver function change were also comparable between the 2 groups. There was no difference with respect to pain scores on movement, nor with respect to patient satisfaction.

Conclusions:

Surgical wound infusion with ropivacaine after hepatectomy can improve pain relief at rest and accelerate recovery and discharge.

Naltrexone attenuates endoplasmic reticulum stress induced hepatic injury in mice

Endoplasmic reticulum (ER) stress provides abnormalities in insulin action, inflammatory responses, lipoprotein B100 degradation and hepatic lipogenesis. Excess accumulation of triglyceride in hepatocytes may also lead to disorders such as non-alcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Opioid peptides are involved in triglyceride and cholesterol dysregulation, inflammation and cell death. In this study, we evaluated Naltrexone effects on ER stress induced liver injury. To do so, C57/BL6 mice received saline, DMSO and Naltrexone, as control groups. ER stress was induced by tunicamycin (TM) injection. Naltrexone was given before TM administration. Liver blood flow and biochemical serum analysis were measured. Histopathological evaluations, TNF-α measurement and Real-time RT-PCR were also performed. TM challenge provokes steatosis, cellular ballooning and lobular inflammation which significantly reduced in Naltrexone treated animals. ALT, AST and TNF-α increased in the TM group and improved in the Naltrexone plus TM group. Triglyceride and cholesterol levels decreased in TM treated mice with no increase in Naltrexone treated animals. In the Naltrexone plus TM group, gene expression of Bax/Bcl-2 ratio and caspase3 significantly lowered compared with the TM group. In this study, we found that Naltrexone had a notable alleviating role in ER stress induced steatosis and liver injury.

Effects of sufentanil on human gastric cancer cell line SGC-7901 in vitro

Sufentanil is a new kind of opioid analgesic and acts on μ opioid receptor. In this study, we aim to investigate the effects of sufentanil on gastric cancer cell line SGC-7901, after being exposed to different concentrations of sufentanil. Gastric cancer cells were exposed to sufentanil for a predetermined time at concentrations of 0, 0.5, 5, 50 and 500 nmol/l, respectively. Cell viability at different time points after exposure to sufentanil was tested by CCK-8 assay. FDA-PI staining was used to observe membrane integrity of gastric cancer SGC7901 cells. The apoptosis of gastric cancer cells was analyzed by Annexin V-FITC/PI Flow Cytometry and the changes of the cell cycle was determined by a detection kit. As a result, cell viability decreased in a dose- and time-dependent manner. Furthermore, with the concentration of sufentanil increased, the proportion of dead and apoptotic SGC-7901 cells increased, and more cells were arrested in G2/M phase. In a word, sufentanil can inhibit the cell viability and induce the apoptosis of gastric cancer SGC-7901 cells in vitro.

Morphine as a Potential Oxidative Stress-Causing Agent

Morphine exhibits important pharmacological effects for which it has been used in medical practice for quite a long time. However, it has a high addictive potential and can be abused. Long-term use of this drug can be connected with some pathological consequences including neurotoxicity and neuronal dysfunction, hepatotoxicity, kidney dysfunction, oxidative stress and apoptosis. Therefore, most studies examining the impact of morphine have been aimed at determining the effects induced by chronic morphine exposure in the brain, liver, cardiovascular system and macrophages. It appears that different tissues may respond to morphine diversely and are distinctly susceptible to oxidative stress and subsequent oxidative damage of biomolecules. Importantly, production of reactive oxygen/nitrogen species induced by morphine, which have been observed under different experimental conditions, can contribute to some pathological processes, degenerative diseases and organ dysfunctions occurring in morphine abusers or morphine-treated patients. This review attempts to provide insights into the possible relationship between morphine actions and oxidative stress.

Nitric oxide mediates the beneficial effect of chronic naltrexone on cholestasis-induced memory impairment in male rats

Recent studies suggest an augmentation of endogenous opioids following bile duct ligation (BDL) and their pivotal role in the pathophysiology of cholestasis. In this study, the effect of naltrexone, an opioid receptor antagonist, was determined on cholestasis-induced memory impairment and the possible involvement of nitric oxide (NO) in this effect. Male Albino-Wistar rats were randomized to sham-operated and BDL-operated groups. In each group, animals were treated for up to 28 days with saline; naltrexone (10 mg/kg); naltrexone and N(G)-nitro-L-arginine methyl ester (L-NAME), a nonselective nitric oxide synthase (NOS) inhibitor (3, 10 mg/kg); naltrexone and aminoguanidine, an inducible NOS inhibitor (100 mg/kg); or methylnaltrexone, a peripherally acting opioid receptor antagonist (3 mg/kg, intraperitoneal). Spatial recognition memory was determined in a Y-maze task on the day before surgery and days 7, 14, 21, and 28 after surgery. Memory performance was impaired 14 days after BDL in cholestatic rats and was significantly reversed by chronic treatment with naltrexone at days 14, 21, and 28 after BDL. On day 21 after BDL, chronic L-NAME produced only a nonsignificant decrease in the beneficial effect of naltrexone, whereas on day 28, chronic administration of both L-NAME and aminoguanidine significantly reversed this effect of naltrexone. It is therefore shown in this study that naltrexone improves BDL-induced memory deficit in rats. We conclude that the memory impairment in cholestatic rats might be because of an increase in the level of endogenous opioids and that naltrexone improved the spatial recognition memory by antagonizing opioid receptors. The observation that the procognitive effect of naltrexone is counteracted either by general inhibition of NOS enzymes or by selective inhibition of inducible NOS suggests the nitrergic pathway as a probable mechanism involved in the amelioration of spatial recognition memory by naltrexone in BDL rats.

The role of anesthetic drugs in liver apoptosis

CONTEXT

The modern practice of anesthesia is highly dependent ona group of anesthetic drugs which many of them are metabolized in the liver.

EVIDENCE ACQUISITION

The liver, of course, usually tolerates this burden. However, this is not always an unbroken rule. Anesthetic induced apoptosis has gained great concern during the last years; especially considering the neurologic system.

RESULTS

However, we have evidence that there is some concern regarding their effects on the liver cells. Fortunately not all the anesthetics are blamed and even some could be used safely, based on the available evidence.

CONCLUSIONS

Besides, there are some novel agents, yet under research, which could affect the future of anesthetic agents' fate regarding their hepatic effects.

A review on renal toxicity profile of common abusive drugs

Drug abuse has become a major social problem of the modern world and majority of these abusive drugs or their metabolites are excreted through the kidneys and, thus, the renal complications of these drugs are very common. Morphine, heroin, cocaine, nicotine and alcohol are the most commonly abused drugs, and their use is associated with various types of renal toxicity. The renal complications include a wide range of glomerular, interstitial and vascular diseases leading to acute or chronic renal failure. The present review discusses the renal toxicity profile and possible mechanisms of commonly abused drugs including morphine, heroin, cocaine, nicotine, caffeine and alcohol.

Geranylgeranylacetone protects against morphine-induced hepatic and renal damage in mice

The acute or chronic administration of opioid drugs may induce oxidative damage and cellular apoptosis in the liver and kidney, and hence result in hepatic and renal damage. Thioredoxin-1 (Trx-1) and heat shock protein 70 (Hsp70) are emerging as important modulators of cellular functions. They have been shown to be involved in cellular protective mechanisms against a variety of toxic stressors. The present study was designed to investigate the effects of geranylgeranylacetone (GGA), a pharmacological inducer of Trx-1 and Hsp70, on morphine-induced hepatic and renal damage. Morphine induced apoptosis in the liver and kidney through the mitochondria-mediated apoptosis pathway, but not the endoplasmic reticulum-mediated pathway. The activation of caspases-9 and -3 was attenuated by pre‑treatment with GGA. In addition, the morphine-induced increase of malondialdehyde (MDA) levels was suppressed by GGA. Furthermore, GGA enhanced morphine-induced expression of Trx-1 and Hsp70 in the liver and kidney. The findings of this study suggest that GGA may be a safe and novel therapeutic agent for morphine‑induced hepatic and renal damage.

Prolonged morphine administration alters protein expression in the rat myocardium

Background

Morphine is used in clinical practice as a highly effective painkiller as well as the drug of choice for treatment of certain heart diseases. However, there is lack of information about its effect on protein expression in the heart. Therefore, here we aimed to identify the presumed alterations in rat myocardial protein levels after prolonged morphine treatment.

Methods

Morphine was administered to adult male Wistar rats in high doses (10 mg/kg per day) for 10 days. Proteins from the plasma membrane- and mitochondria-enriched fractions or cytosolic proteins isolated from left ventricles were run on 2D gel electrophoresis, scanned and quantified with specific software to reveal differentially expressed proteins.

Results

Nine proteins were found to show markedly altered expression levels in samples from morphine-treaded rats and these proteins were identified by mass spectrometric analysis. They belong to different cell pathways including signaling, cytoprotective, and structural elements.

Conclusions

The present identification of several important myocardial proteins altered by prolonged morphine treatment points to global effects of this drug on heart tissue. These findings represent an initial step toward a more complex view on the action of morphine on the heart.

HIV-1 coinfection and morphine coexposure severely dysregulate hepatitis C virus-induced hepatic proinflammatory cytokine release and free radical production: increased pathogenesis coincides with uncoordinated host defenses

Coinfection with human immunodeficiency virus type-1 (HIV-1) and hepatitis C virus (HCV) is a global problem that is more prevalent in injection drug users because they have a higher risk for acquiring both viruses. The roles of inflammatory cytokines and oxidative stress were examined in HIV-1- and HCV-coinfected human hepatic cells. Morphine (the bioactive product of heroin), HIV-1 Tat and the MN strain gp120 (gp120(MN)) proteins, and X4 HIV-1(LAI/IIIB) and R5 HIV-1(SF162) isolates were used to study the mechanisms of disease progression in HCV (JFH1)-infected Huh7.5.1 cell populations. HCV increased tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) release and augmented production of reactive oxygen species (ROS), nitric oxide (NO), and 3-nitrotyrosine (3-NT) in Huh7.5.1 cells. Morphine preferentially affected R5-tropic, but not X4-tropic, HIV-1 interactions with Huh7.5.1 cells. HIV-1 proteins or isolates increased cytokine release in HCV-infected cells, while adding morphine to coinfected cells caused complex imbalances, significantly disrupting cytokine secretion depending on the cytokine, morphine concentration, exposure duration, and particular pathogen involved. Production of ROS, NO, and 3-NT increased significantly in HCV- and HIV-1-coexposed cells while exposure to morphine further increased ROS. The proteasome inhibitor MG132 significantly decreased oxyradicals, cytokine levels, and HCV protein levels. Our findings indicate that hepatic inflammation is increased by combined exposure to HCV and HIV-1, that the ubiquitin-proteasome system and NF-κB contribute to key aspects of the response, and that morphine further exacerbates the disruption of host defenses. The results suggest that opioid abuse and HIV-1 coinfection each further accelerate HCV-mediated liver disease by dysregulating immune defenses.

Insight into pain-inducing and -related gene expression: a challenge for development of novel targeted therapeutic approaches

The multidimensional issue of pain in relation to the need for efficient treatment has been the focus of extensive research. Gaining insight into the molecular mechanisms of pain and identifying specific genes and proteins as possible drug targets is strongly required considering that not all patients can be adequately treated with the currently available drugs. This up-to-date review aimed to summarize the findings of recent proteomic and genomic approaches in different types of pain to comment on their potential role in pain signaling pathways and to evaluate their possible contribution to the development of novel and possibly more targeted pain therapeutic strategies. Although pain treatment strategies have been greatly improved during the past century, no ideal targeted pain treatment has been developed. The development of modern and accurate platforms of technology for the study of genetics and physiology of pain has led to the identification of an increased number of altered genes and proteins that are involved in pain-related pathways. Through genomics and proteomics, pain-related genes and proteins, respectively, may be identified as diagnostic markers or drug targets improving therapeutic strategies. Furthermore, such molecular mediators of pain may reveal novel strategies for individualized pain management. The utilization of unique experimental approaches (through specific animal models) as well as powered genetic association studies conducted on appropriate populations is more than essential.

In vivo morphine treatment synergistically increases LPS-induced caspase activity in immune organs

Caspases are a family of proteins important for the elimination of infected cells through the induction of apoptosis as well as the initiation of inflammatory cytokines including IL-1β and IL-18. Morphine exposure to animals and/or cells has been associated with the induction of apoptosis. The most common practices of apoptosis detection have involved removing tissues from animal or humans and the analysis of apoptosis on cells or tissues. These methods can potentially induce spontaneous apoptosis that is unrelated to the actual treatment. The objective of this study was to develop an in vivo detection method for assessing caspase activity induced both by morphine directly and by morphine combined with lipopolysaccharide (LPS)-immune activation. Mice were administered saline, morphine, LPS, or a combination of morphine and LPS. Prior to sacrifice, mice were injected with a polycaspase-specific apoptosis detection probe to detect internal caspase activity in vivo. Results revealed that morphine alone did not directly induce caspase activity. However, morphine significantly enhanced the LPS-induced caspase activity in spleen, thymus, and bone marrow-derived immune cells. The use of a poly-caspase detection probe methodology to label caspase activity in vivo provides a powerful quantitative tool for the in vivo analysis of caspase activity.

Histopathological and biochemical changes of morphine sulphate administration on the cerebellum of albino rats

In this study the long-term effects of morphine sulphate treatment (MST) on histopathological and biochemical changes in the cerebellum was assessed in albino rats. Normal saline (5ml) was given orally as placebo in the control group (n=25). Morphine groups received morphine orally at a dose level of 5mg/kg body weight day after day for 10, 20 and 30 days (n=25/group). Light microscopy revealed that the molecular layer showed vacuolation. The Purkinje cells lost their specific shaped appearance, decreased in size and numbers. The granular cells highly degenerated. Electron microscopy revealed fragmentation of the cisterns of the both types of endoplasmic reticulum, resulted in a progressive depletion of total protein contents as well as general carbohydrates in all treated groups as supported by histochemical observation. Obvious destruction of mitochondrial inner membrane and cristae mediate cell death. Also, abnormal nucleus with deformed perforated nuclear membrane and deformation of the plasma membrane with degeneration of the synapses could interpreted as a sign of necrosis. Biochemical analysis revealed that dopamine (DA) and norepinephrine (NE) were significantly decreased in four brain areas (cortex striatum, thalamus/hypothalamus, and cerebellum). In contrast, serotonin (5-HT) level was increased in these brain regions; with an exception of 5-HT on day 10 and neurotransmitter levels in the pons were unaffected. The quantitative analysis showed a significant decrease (P<0.05) in the diameter of Purkinje cells and in the thickness of both molecular and granular layers treated groups. Morphine sulphate induces may be a cell death or necrosis in the rat cerebellum and modulating neurotransmitter system. Our findings pointed out the risk of increased cerebellum damage due to long-term of morphine use.

Characteristics of chronic hepatitis C among intravenous drug users: a comparative analysis

Hepatitis C virus (HCV) usually evades the host's immune system and persists as a chronic infection. Intravenous drug users (IVDU) represent the majority of patients infected with HCV. Combined therapy of chronic hepatitis C (CHC) with peginterferon alpha-2a and ribavirin can be successful even when patients continue the intravenous drug use. In this study, we compared the characteristics of age, gender, genotype, and stage of fibrosis and the therapy outcome among IVDU and patients with no history of drug use. The study included 69 patients diagnosed with chronic hepatitis C, evaluated and treated at the Clinic for infectious diseases in Nis from 2005 to 2009. HCV RNA was detected by a polymerase chain reaction and the determination of genotypes was undertaken. Liver biopsies were examined histopathologically. Patients received a combined treatment of peginterferon alfa-2a and ribavirin. Therapy efficiency was evaluated based on the achievement of the sustained virological response (SVR). A comparison of characteristics was performed with the use of Mann-Whitney U test, chi-square (chi2) test and logistic regression. IVDU were significantly younger than patients in the control group. Prevalence of stage 1 fibrosis was significantly higher among IVDU. The therapy outcome is influenced by the patient's age and HCV genotypes. Each year added to one patient decreased the therapy efficiency by 8.1%, while genotypes 2 and 3 experienced a therapy which was 2.08 times more efficient than in other cases. IVDU represent a specific population different from non-using patients. However, they can be treated effectively if an adequate patient-doctor relationship is established.

Morphine sulphate induced histopathological and histochemical changes in the rat liver

In this study, the histopathological and histochemical changes due to chronic usage of morphine sulphate in liver were assessed in rats with both light and electron microscopes. Twenty male albino rats (Rattus norvegicus) (130-150 g) were included and divided into four groups. Normal saline (5 ml) was given orally as placebo in the control group (N=5). Morphine groups (N=5) received morphine orally at a single dose of 5 ml/kg/day for 10, 20 and 30 days (groups II, III and IV), respectively. Liver specimens from all groups were evaluated for histopathological and histochemical changes. Light microscopy revealed severe centrilobular congestion, portal fibrosis with bile ductal proliferation and an increased inflammatory infiltration and focal parenchymal necrosis. Histochemical study revealed a progressive depletion of general carbohydrates and an increase in total protein contents. These changes were confirmed at ultrastructural level, including the presence of accumulated lipid in the hepatocytes; deposits of a collagen-like fibrous material were seen in the space of Disse and a reduction in the number of endothelial cell fenestrations. Our findings pointed out the risk of increased lipid fibrosis and hepatic damage due to long-term use of morphine. Although opioids are reported to be effective in pain management, their toxic effects should be kept in mind during chronic usage.

Opioid use affects antioxidant activity and purine metabolism: preliminary results

OBJECTIVE

More must be learned about metabolic and biochemical alterations that contribute to the development and expression of drug dependence. Experimental opioid administration influences mechanisms and indices of oxidative stress, such as antioxidant compounds and purine metabolism. We examined perturbations of neurotransmitter-related pathways in opioid dependence (OD).

METHODS

In this preliminary study, we used a targeted metabolomics platform to explore whether biochemical changes were associated with OD by comparing OD individuals (n = 14) and non-drug users (n = 10).

RESULTS

OD patients undergoing short-term methadone detoxification showed altered oxidation-reduction activity, as confirmed by higher plasma levels of alpha- and gamma-tocopherol and increased GSH/GSSG ratio. OD individuals had also altered purine metabolism, showing increased concentration of guanine and xanthosine, with decreased guanosine, hypoxanthine and hypoxanthine/xanthine and xanthine/xanthosine ratios. Other drug use in addition to opioids was associated with partly different biochemical changes.

CONCLUSIONS

This is a preliminary investigation using metabolomics and showing multiple peripheral alterations of metabolic pathways in OD. Further studies should explore the metabolic profile of conditions of opioid abuse, withdrawal and long-term abstinence in relation to agonist and antagonist treatment and investigate biochemical signatures of opioid substances and medications.

Morphine induces apoptosis of human endothelial cells through nitric oxide and reactive oxygen species pathways

Morphine has been widely used for pain management. Other than analgesia, it has effects on vascular endothelial cells, including angiogenesis and apoptosis. An in vitro model of human umbilical vein endothelial cells (HUVECs) was made to investigate the effects and comprehensive mechanisms of morphine on vascular endothelial cells. Morphine enhanced apoptosis of HUVECs, increased intracellular reactive oxygen species (ROS), and reduced mitochondrial membrane potentials (MMPs). It also induced the release of NO and activated NF-kappaB in HUVECs. Naloxone, the opioid receptor antagonist, could reverse cell apoptosis and ROS generation, NO production, and MMP loss. Expression levels of Bak and Bax, and the activation of caspases 3 and 7 in HUVECs significantly increased when treated with morphine. Inhibition of NO production by NO synthase inhibitor reduced morphine-induced apoptosis. Morphine could induce apoptosis of HUVECs through both the NO and ROS pathways. Thus, inhibiting NO or ROS may be a potential target in blocking morphine-induced apoptosis of endothelial cells.