Morphine-induced degradation of the host defense barrier role of intestinal mucosal injury

The Reasons for Higher Mortality Rate in Opium Addicted Patients with COVID-19: A Narrative Review

The outbreak of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) caused COVID-19 has developed into an unexampled worldwide pandemic. The most important cause of death in patients with COVID-19 is Acute Respiratory Distress Syndrome (ARDS). Opium is widely used for its analgesic features in control of acute and chronic pain related to different diseases. Opium consumption is increased over the last three decades and leads to adverse effects on the respiratory system; opium also affects the lungs' functions and respiration. The contemplative issue is the higher mortality rate due to SARS-CoV-2 infection in opium addicts' patients. Studies have shown that despite the decrease in proinflammatory cytokines production in opium addicts, there are at least 4 reasons for this increase in mortality rate: downregulation of IFNs expression, development of pulmonary edema, increase thrombotic factors, increase the expression of Angiotensin-converting enzyme 2 (ACE2). Therefore, identifying the causes of mortality and approved therapies for the treatment of COVID-19 patients who use opium for any reason is an important unmet need to reduce SARS-CoV-2 infection-related mortality. This review study demonstrated the effects of opium on immune responses and the reasons for the higher mortality rate in opium addicts' patients with COVID-19.

Bio-engineered palladium nanoparticles: model for risk assessment study of automotive particulate pollution on macrophage cell lines

The surge in vehicular activity in densely populated areas has led to an increased concentration of airborne palladium nanoparticles (PdNPs) in the environment. Recent toxicity data have indicated that PdNPs exhibit adverse effects in in vitro and in vivo models, however, their effect on the immune system is not fully understood. Therefore, in the present study, we aimed to evaluate possible toxic effects of bio-engineered palladium nanoparticles on the murine macrophage cell line (J774). Here we prepared palladium nanoparticles using aqueous leaf extract of Parthenium hysterophorus and characterized them by UV-Vis spectroscopy, XRD, FT-IR spectroscopy, HR-TEM, EDX, SEM and zeta potential. Toxicity parameters such as cell viability, cell membrane integrity, induction of apoptosis and ROS production were assessed on J774 cell lines. Spherical palladium nanoparticles of mean size ∼4 nm, when subjected to time and dose-dependent cytotoxicity assay, showed cell viability was >95% at lower doses (25, 200 μg mL-1) and <50% at higher doses of palladium nanoparticles (400, 500 μg mL-1) after 24 hours of incubation. We also observed cell membrane injury at higher doses by lactate dehydrogenase assay. The induction of apoptosis observed was moderate. H2DCFDA assay revealed visible cell damage which could be due to modest levels of ROS generation. The detection of Pd in the road-dust samples of New Delhi using inductively coupled plasma-mass spectroscopy (ICP-MS) technique was also investigated.

Opioids in Cancer Development, Progression and Metastasis: Focus on Colorectal Cancer

OPINION STATEMENT

So far, opioids have been successfully used to reduce cancer pain in patients in order to improve their quality of life. However, the use of opioids leads to numerous side effects such as constipation, drowsiness, nausea, itching, increased sweating and hormonal changes. In this review, we described the action of opioids in several molecular pathways significant for maintenance of the intestinal homeostasis including the impact on the intestinal epithelium integrity, changes in microbiome composition, modulation of the immune system or induction of apoptosis and inhibition of angiogenesis. We summed up the role of individual opioids in the processes involved in the growth and development of cancer and elucidated if targeting opioid receptors may constitute novel therapeutic option in colon cancer.

Opium Consumption and the Incidence of Cancer: Does Opium Account as an Emerging Risk Factor for Gastrointestinal Cancer?

PURPOSE

Some epidemiological studies have shown an association between opium consumption and the incidence of gastrointestinal (GI) cancer. The present study was designed to investigate the effects of opium on the initiation of GI cancer in rats.

METHODS

Forty-five rats were randomly divided into three groups; each received different treatment for 40 weeks. The rats in group 1 received purified water, while animals in group 2 were treated with 5 mg/kg diethylnitrosamine (DEN) orally for 8 weeks and continued with purified water by the end of the experiment. The third experimental group received 300 mg/kg opium for 16 weeks and then continued with 50 mg/kg phenobarbital by the end of the 40th week. The growth of tumors in the treated groups was assessed by histological changes and the up/down expression of p53, cdkn1, cdk2, e-cdh, and n-cdh genes in different parts of GI tract.

RESULTS

Histological examinations revealed that DEN was able to induce the growth of tumor in GI tract as shown by active mitotic figure in different regions of GI system and hyperplasia of hepatocytes associated with infiltration of inflammatory cells, intestinal villous hypertrophy, and colorectal adenoma. There was also significant (p < 0.05) overexpression of p53, cdk2, and n-Cdh genes in different parts of digestive system in DEN-treated group. However, these pathological changes and the degradation of gene expression were not observed in the opium-treated group.

CONCLUSION

The results of this study suggest that the opium does not promote the initiation of cancer in GI tract.

Perioperative Immunosuppression and Risk of Cancer Progression: The Impact of Opioids on Pain Management

Opioids comprise an important group of drugs used in cancer pain pharmacotherapy. In recent years, more and more studies have emerged indicating the potentially immunosuppressive effects of opioid analgesics and their serious consequences, including the risk of cancer progression. The identification of these risks has prompted a search for other effective, and most importantly, safer methods of perioperative analgesic management. Regional analgesia techniques, which allow for a significant reduction in opioid dosing and thus diminish the risk of immunosuppression associated with these drugs, seem to offer substantial hope in this respect. A number of studies available in the literature assess the effects of regional analgesia techniques on cancer progression; however, it is often difficult to interpret their results owing to several perioperative factors (such as surgical trauma, inadequate pain and stress relief, and hypothermia) which are also attributed immunosuppressive effects and tend to be implicated in increased risk of cancer progression. Further research is needed to verify the available data on both the potential adverse effects of opioids and the possible protective effects of regional analgesia techniques on cancer patients.

GC-MS-based plasma metabolomic investigations of morphine dependent rats at different states of euphoria, tolerance and naloxone-precipitated withdrawal

Long-term or excessive application of morphine leads to tolerance and addiction, which hindered its conventional applications as a drug. Although tremendous progress has been made on the mechanisms of morphine, crucial evidence elaborating the neurobiological basis of tolerance and dependence is still lacking. To further explore the physiological adaptions during morphine's application, a systematic screening of small molecules in blood has been carried out. The plasma of morphine dependent rats was collected at different time points with or without naloxone treatment, and was analyzed by gas chromatography-mass spectrometry (GC-MS). Partial least squares discriminate analysis (PLS-DA) and the Student's t Tests with the false discovery rate (FDR) correction were conducted on the normalized data for the distinction of groups and the identification of the most contributed metabolites. Clear separation is observed between different treatments, and 29 out of 41 metabolites changes significantly compared with the corresponding controls. The concentration of threonine, glycine, serine, beta-d-glucose and oxalic acid are consistently changed in all morphine treated groups compared with controls. Through this experiment we find characteristic metabolites in different dependent states and discuss the possible compensation effects. The interpretation of these metabolites would throw light on the biological effects of morphine and reveal the possibilities to become marker of morphine addiction.

Opioid effect on lungs

Opioids are widely used for their analgesic properties for the management of acute and chronic pain related to a variety of illnesses. Opioid usage is associated with adverse effects on respiration which are often attributed to depression of the central nervous system. Recent data indicate that opioid use has increased over the last two decades. There is also increasing evidence that opioids have a variety of effects on the lungs besides suppression of respiration. Opioids can affect immune cells function, increase histamine release causing bronchospasm, vaso-constriction and hypersensitivity reactions. Together, these actions have a variety of effects on lung function. Here, we provide a comprehensive review of the effects of opioids on the lungs including the respiratory centre, immune function, airways and pulmonary vasculature.

Opioids and immune modulation: more questions than answers

Opioid addicts are more likely to present with infections suggesting opioids are immune modulators. The potential sites/mechanism(s) for this modulation are controversial and on close inspection not well supported by the current literature. It has long been assumed that opioid-induced immune modulation occurs via a combination of direct actions on the immune cell itself, via the hypothalamic-pituitary-adrenal (HPA) axis, or both. Opioid receptors are classified as MOP (μ, mu), DOP (δ, delta), and KOP (κ, kappa)--classical naloxone sensitive receptors--or NOP (the receptor for nociceptin/orphanin FQ), which is naloxone insensitive. Opioids currently used in clinical practice predominantly target the MOP receptor. There do not appear to be classical opioid receptors present on immune cells. The evidence for HPA activation is also poor and shows some species dependence. Most opioids used clinically or as drugs of abuse do not target the NOP receptor. Other possible target sites for immune modulation include the sympathetic nervous system and central sites. We are currently unable to accurately define the cellular target for immune modulation and suggest further investigation is required. Based on the differences observed when comparing studies in laboratory animals and those performed in humans we suggest that further studies in the clinical setting are needed.

Influence of morphine on host immunity

Morphine is a widely used drug for analgesia and substance abuse. It has been accepted as a safe medication with great analgesic efficacy. Previous studies have reported that morphine is highly associated with the risk of immunosuppressive effects. Although the observed clinical effects suggest that morphine has the immunomodulatory capabilities, the mechanism of its action is still unclear. Here we review morphine on the bench to improve our understanding of the drug on the host immunity at the bedside. Studies of the effects of morphine on the innate and adaptive immune systems as well as immune responses are also discussed.

Concentration-dependent toxicity of iron oxide nanoparticles mediated by increased oxidative stress

Iron oxide nanoparticles with unique magnetic properties have a high potential for use in several biomedical, bioengineering and in vivo applications, including tissue repair, magnetic resonance imaging, immunoassay, drug delivery, detoxification of biologic fluids, cell sorting, and hyperthermia. Although various surface modifications are being done for making these nonbiodegradable nanoparticles more biocompatible, their toxic potential is still a major concern. The current in vitro study of the interaction of superparamagnetic iron oxide nanoparticles of mean diameter 30 nm coated with Tween 80 and murine macrophage (J774) cells was undertaken to evaluate the dose- and time-dependent toxic potential, as well as investigate the role of oxidative stress in the toxicity. A 15–30 nm size range of spherical nanoparticles were characterized by transmission electron microscopy and zeta sizer. MTT assay showed >95% viability of cells in lower concentrations (25–200 μg/mL) and up to three hours of exposure, whereas at higher concentrations (300–500 μg/mL) and prolonged (six hours) exposure viability reduced to 55%–65%. Necrosis-apoptosis assay by propidium iodide and Hoechst-33342 staining revealed loss of the majority of the cells by apoptosis. H₂DCFDDA assay to quantify generation of intracellular reactive oxygen species (ROS) indicated that exposure to a higher concentration of nanoparticles resulted in enhanced ROS generation, leading to cell injury and death. The cell membrane injury induced by nanoparticles studied using the lactate dehydrogenase assay, showed both concentration- and time-dependent damage. Thus, this study concluded that use of a low optimum concentration of superparamagnetic iron oxide nanoparticles is important for avoidance of oxidative stress-induced cell injury and death.

Endogenous opiates and behavior: 2006

This paper is the 29th consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning 30 years of research. It summarizes papers published during 2006 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurological disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).