Microbial Infections, Immunomodulation, and Drugs of Abuse

Abstract

The use of recreational drugs of abuse has generated serious health concerns. There is a long-recognized relationship between addictive drugs and increased levels of infections. Studies of the mechanisms of actions of these drugs became more urgent with the advent of AIDS and its correlation with abused substances. The nature and mechanisms of immunomodulation by marijuana, opiates, cocaine, nicotine, and alcohol are described in this review. Recent studies of the effects of opiates or marijuana on the immune system have demonstrated that they are receptor mediated, occurring both directly via specific receptors on immune cells and indirectly through similar receptors on cells of the nervous system. Findings are also discussed that demonstrate that cocaine and nicotine have similar immunomodulatory effects, which are also apparently receptor mediated. Finally, the nature and mechanisms of immunomodulation by alcohol are described. Although no specific alcohol receptors have been identified, it is widely recognized that alcohol enhances susceptibility to opportunistic microbes. The review covers recent studies of the effects of these drugs on immunity and on increased susceptibility to infectious diseases, including AIDS

Anti-Inflammatory Properties of Anesthetic Agents

“…Diverse in vitro experiments with human immune cells ex vivo [2], in vivo tests [10] and animal models have demonstrated a wide range of effects of anesthetic drugs on the immune system, including changes in immune cell counts and their functionality and effects on the secretion patterns of diverse immune mediators, affecting the inflammatory response in the postoperative period [1][2][3].…”

“…Its principal components are the epithelial membranes (which block pathogen entry), phagocytic cells (neutrophils * Correspondence: ppelosi@hotmail.com 2 Department of Surgical Sciences and Integrated Diagnostics, IRCCS AOU San Martino IST, University of Genoa, 16132 Genoa, Italy Full list of author information is available at the end of the article and macrophages), dendritic cells, natural killer (NK) cells and several plasma proteins, including the complement system. The most important cellular reaction of innate immunity is inflammation -the process, mediated by dendritic and NK cells, whereby phagocytic cells are recruited and activated to eliminate aggressor agents [2,3].…”

“…To avoid a potential detrimental effect of long-term sedation in critically ill patients, the duration and the doses of sedative agents should be kept as low as possible, not least because these patients are immunocompromised. Daily wake-up trials are recommended to reduce the risk of oversedation [1][2][3][4].…”

Morphine Withdrawal Inhibits IL-12 Induction in a Macrophage Cell Line through a Mechanism That Involves cAMP

“…CRL-2019 cells were treated as described above and, after 24 h of in vitro withdrawal, cells were stimulated with LPS for 5, 10, and 20 min. Following the stimulation, the cells were lysed, whole cell lysates were prepared and separated on 3 Abbreviations used in this paper: MOR, opioid receptor; IKK, I B kinase; PKA, protein kinase A. . CRL-2019 macrophages were cultured and treated as described above and stimulated overnight with 5 g/ml LPS.…”

Evaluation of the alum–naloxone adjuvant activity against experimental murine leishmaniasis due to L. major

“…The activation of Th1 responses is associated with the production of cytokines such as IFN-c and IL-12 which stimulate the microbicidal activity of macrophages (Ameen 2010). Exposure to opioids increases the susceptibility to bacterial, fungal, and opportunistic infections (Friedman et al 2003;Roy et al 2011). It is now clear that the endogenous opioids modulate both innate and acquired immune responses (McCarthy et al 2001).…”