Effects of Methamphetamine on Cortisone Concentration, NK Cell Activity and Mitogen Response of T-lymphocytes in Female Cynomolgus Monkeys

Immunity on ice: The impact of methamphetamine on peripheral immunity

Methamphetamine (METH) regulation of the dopamine transporter (DAT) and central nervous system (CNS) dopamine transmission have been extensively studied. However, our understanding of how METH influences neuroimmune communication and innate and adaptive immunity is still developing. Recent studies have shed light on the bidirectional communication between the CNS and the peripheral immune system. They have established a link between CNS dopamine levels, dopamine neuronal activity, and peripheral immunity. Akin to dopamine neurons in the CNS, a majority of peripheral immune cells also express DAT, implying that in addition to their effect in the CNS, DAT ligands such as methamphetamine may have a role in modulating peripheral immunity. For example, by directly influencing DAT-expressing peripheral immune cells and thus peripheral immunity, METH can trigger a feed-forward cascade that impacts the bidirectional communication between the CNS and peripheral immune system. In this review, we aim to discuss the current understanding of how METH modulates both innate and adaptive immunity and identify areas where knowledge gaps exist. These gaps will then be considered in guiding future research directions.

Dynamic immune and exosome transcriptomic responses in patients undergoing psychostimulant methamphetamine withdrawal

Methamphetamine (METH) addiction and withdrawal cause serious harm to both the immune system and nervous system. However, the pathogenesis remains largely unknown. Herein, we investigated the peripheral cytokines and exosomal transcriptome regulatory networks in the patients with METH use disorders (MUDs) undergoing withdrawal. Twenty-seven cytokines were simultaneously assessed in 51 subjects, including 22 at the acute withdrawal (AW) stage and 29 at the protracted withdrawal (PW) stage, and 31 age and gender-matched healthy controls (HCs). Compared to the HCs, significantly decreased levels of interleukin (IL)-1β, IL-9, IL-15, Basic FGF, and MIP1a, increased levels of IL-1rα, IL-6, Eotaxin IP-10, VEGF, and RANTES were identified in AW. These disturbances were mostly or partly restored to the baseline in PW. However, the cytokines IL-6, IL-7, and IL-12p70 were consistently increased even after one year of withdrawal. Besides, a significant decrease in CD3+T and CD4+T cell numbers was observed in AW, and the diminishment was restored to baseline in PW. Comparatively, there were no statistically significant changes in CD8+T, NK, and B cells. Furthermore, the exosomal mRNAs and long non-coding RNAs (lncRNA) were profiled, and the lncRNA-miRNA-mRNA networks were constructed and associated with METH AW and PW stages. Notably, the chemokine signaling was remarkably upregulated during AW. By contrast, the differentially expressed mRNAs/lincRNAs were significantly enriched in neurodegeneration-related diseases. Taken together, a group of METH withdrawal-related cytokines and exosomal mRNA/lncRNA regulatory networks were obtained, which provides a useful experimental and theoretical basis for further understanding of the pathogenesis of the withdrawal symptoms in MUDs.

Drugs and Bugs: The Gut-Brain Axis and Substance Use Disorders

Substance use disorders (SUDs) represent a significant public health crisis. Worldwide, 5.4% of the global disease burden is attributed to SUDs and alcohol use, and many more use psychoactive substances recreationally. Often associated with comorbidities, SUDs result in changes to both brain function and physiological responses. Mounting evidence calls for a precision approach for the treatment and diagnosis of SUDs, and the gut microbiome is emerging as a contributor to such disorders. Over the last few centuries, modern lifestyles, diets, and medical care have altered the health of the microbes that live in and on our bodies; as we develop, our diets and lifestyle dictate which microbes flourish and which microbes vanish. An increase in antibiotic treatments, with many antibiotic interventions occurring early in life during the microbiome's normal development, transforms developing microbial communities. Links have been made between the microbiome and SUDs, and the microbiome and conditions that are often comorbid with SUDs such as anxiety, depression, pain, and stress. A better understanding of the mechanisms influencing behavioral changes and drug use is critical in developing novel treatments for SUDSs. Targeting the microbiome as a therapeutic and diagnostic tool is a promising avenue of exploration. This review will provide an overview of the role of the gut-brain axis in a wide range of SUDs, discuss host and microbe pathways that mediate changes in the brain's response to drugs, and the microbes and related metabolites that impact behavior and health within the gut-brain axis.

Methamphetamine Dysregulation of the Central Nervous System and Peripheral Immunity

Methamphetamine (METH) is a potent psychostimulant that increases extracellular monoamines, such as dopamine and norepinephrine, and affects multiple tissue and cell types in the central nervous system (CNS) and peripheral immune cells. The reinforcing properties of METH underlie its significant abuse potential and dysregulation of peripheral immunity and central nervous system functions. Together, the constellation of METH's effects on cellular targets and regulatory processes has led to immune suppression and neurodegeneration in METH addicts and animal models of METH exposure. Here we extensively review many of the cell types and mechanisms of METH-induced dysregulation of the central nervous and peripheral immune systems. SIGNIFICANCE STATEMENT: Emerging research has begun to show that methamphetamine regulates dopaminergic neuronal activity. In addition, METH affects non-neuronal brain cells, such as microglia and astrocytes, and immunological cells of the periphery. Concurrent disruption of bidirectional communication between dopaminergic neurons and glia in the CNS and peripheral immune cell dysregulation gives rise to a constellation of dysfunctional neuronal, cell, and tissue types. Therefore, understanding the pathophysiology of METH requires consideration of the multiple targets at the interface between basic and clinical neuroscience.

Role of Autophagy in HIV Pathogenesis and Drug Abuse

Autophagy is a highly regulated process in which excessive cytoplasmic materials are captured and degraded during deprivation conditions. The unique nature of autophagy that clears invasive microorganisms has made it an important cellular defense mechanism in a variety of clinical situations. In recent years, it has become increasingly clear that autophagy is extensively involved in the pathology of HIV-1. To ensure survival of the virus, HIV-1 viral proteins modulate and utilize the autophagy pathway so that biosynthesis of the virus is maximized. At the same time, the abuse of illicit drugs such as methamphetamine, cocaine, morphine, and alcohol is thought to be a significant risk factor for the acquirement and progression of HIV-1. During drug-induced toxicity, autophagic activity has been proved to be altered in various cell types. Here, we review the current literature on the interaction between autophagy, HIV-1, and drug abuse and discuss the complex role of autophagy during HIV-1 pathogenesis in co-exposure to illicit drugs.

The overexpression of Thioredoxin-1 suppressing inflammation induced by methamphetamine in spleen

BACKGROUND

Methamphetamine (METH) is an addictive psychostimulant and has been shown to induce oxidative stress and inflammation in various tissues. Thioredoxin-1 (Trx-1) plays the roles in regulating redox and inhibiting inflammation. Whether Trx-1 is involved in METH-induced inflammation is still unknown.

METHODS

The present study was designed to investigate inflammatory factors in spleen of wild type and Trx-1 overexpression transgenic mice after METH treatment.

RESULTS

We found the mRNA level of Trx-1 was decreased and mRNA level of Trx-1 binding protein-2 (TBP-2) was increased. The mRNA levels of tumor necrosis factor-α (TNF-α), interferon-γ(IFN-γ), interleukin-2 (IL-2), T-bet and signal transducer and activators of transcription 4 (STAT 4) were increased and the mRNA levels of IL-10, GA-TA-binding protein-3 (GATA-3) and STAT 6 were decreased. Overexpression of Trx-1 reversed the above effects induced by METH.

CONCLUSION

The present study showed for the first time that Trx-1 overexpression suppressed the inflammation induced by METH.

Plasma Inflammatory Factors Are Associated with Anxiety, Depression, and Cognitive Problems in Adults with and without Methamphetamine Dependence: An Exploratory Protein Array Study

OBJECTIVES

It is hypothesized that immune factors influence addictive behaviors and contribute to relapse. The primary study objectives were to (1) compare neuropsychiatric symptoms across adults with active methamphetamine (MA) dependence, in early remission from MA dependence, and with no history of substance dependence, (2) determine whether active or recent MA dependence affects the expression of immune factors, and (3) evaluate the association between immune factor levels and neuropsychiatric symptoms.

METHODS

A cross-sectional study was conducted using between group comparisons and regression analyses to investigate associations among variables. Eighty-four adults were recruited into control (CTL) (n = 31), MA-active (n = 17), or MA-remission (n = 36) groups. Participants completed self-report measures of anxiety, depression, and memory complaints and objective tests of attention and executive function. Blood samples were collected, and a panel of immune factors was measured using multiplex technology.

RESULTS

Relative to CTLs, MA-dependent adults evidenced greater anxiety and depression during active use (p < 0.001) and remission (p < 0.007), and more attention, memory, and executive problems during remission (p < 0.01) but not active dependence. Regression analyses identified 10 immune factors (putatively associated with cytokine-cytokine receptor interactions) associated with anxiety, depression, and memory problems.

CONCLUSION

While psychiatric symptoms are present during active MA dependence and remission, at least some cognitive difficulties emerge only during remission. Altered expression of a network of immune factors contributes to neuropsychiatric symptom severity.

Neuroimmune basis of methamphetamine toxicity

Although it is not known which antigen-specific immune responses (or if antigen-specific immune responses) are relevant or required for methamphetamine's neurotoxic effects, it is apparent that methamphetamine exposure is associated with significant effects on adaptive and innate immunity. Alterations in lymphocyte activity and number, changes in cytokine signaling, impairments in phagocytic functions, and glial activation and gliosis have all been reported. These drug-induced changes in immune response, particularly within the CNS, are now thought to play a critical role in the addiction process for methamphetamine dependence as well as for other substance use disorders. In Section 2, methamphetamine's effects on glial cell (e.g., microglia and astrocytes) activity and inflammatory signaling cascades are summarized, including how alterations in immune cell function can induce the neurotoxic and addictive effects of methamphetamine. Section 2 also describes neurotransmitter involvement in the modulation of methamphetamine's inflammatory effects. Section 3 discusses the very recent use of pharmacological and genetic animal models which have helped elucidate the behavioral effects of methamphetamine's neurotoxic effects and the role of the immune system. Section 4 is focused on the effects of methamphetamine on blood-brain barrier integrity and associated immune consequences. Clinical considerations such as the combined effects of methamphetamine and HIV and/or HCV on brain structure and function are included in Section 4. Finally, in Section 5, immune-based treatment strategies are reviewed, with a focus on vaccine development, neuroimmune therapies, and other anti-inflammatory approaches.

Impact of methamphetamine on infection and immunity

The prevalence of methamphetamine (METH) use is estimated at ~35 million people worldwide, with over 10 million users in the United States. METH use elicits a myriad of social consequences and the behavioral impact of the drug is well understood. However, new information has recently emerged detailing the devastating effects of METH on host immunity, increasing the acquisition of diverse pathogens and exacerbating the severity of disease. These outcomes manifest as modifications in protective physical and chemical defenses, pro-inflammatory responses, and the induction of oxidative stress pathways. Through these processes, significant neurotoxicities arise, and, as such, chronic abusers with these conditions are at a higher risk for heightened consequences. METH use also influences the adaptive immune response, permitting the unrestrained development of opportunistic diseases. In this review, we discuss recent literature addressing the impact of METH on infection and immunity, and identify areas ripe for future investigation.

Association of leukocytosis with amphetamine and cocaine use

OBJECTIVE

Determining the etiology of unexplained leukocytosis in asymptomatic patients may incur unnecessary testing, cost, and prolonged emergency department stay. The objective was to delineate if use of amphetamines and/or cocaine is a factor.

METHODS

For two years we reviewed all psychiatric patients presenting for medical clearance with exclusions for infection, epilepsy, trauma, or other nonpsychiatric medical conditions.

RESULTS

With a total of 1,206 patients, 877 (72.7%) amphetamines/cocaine-negative drug screen controls had mean WBC 8.4 ± 2.6 × 10³/µL. The 240 (19.9%) amphetamines-positive, cocaine-negative, patients had WBC 9.4 ± 3.3 × 10³/µL (P < 0.0001). The 72 (6.0%) amphetamines-negative, cocaine-positive, patients had WBC 7.1 ± 1.8 × 10³/µL (P < 0.0001). The remaining 17 (1.4%) amphetamines/cocaine-positive patients had WBC 10.0 ± 4.2 × 10³/µL (P = 0.01). Amphetamines-positive patients had a supranormal WBC ratio significantly higher than controls (23.8% versus 14.8%, P = 0.001), whereas only one cocaine-positive patient had a supranormal WBC count, with significantly lower ratio (1.4%, P = 0.0003).

CONCLUSION

Use of amphetamines, not cocaine, may be associated with idiopathic leukocytosis. This may be explained by unique pharmacologic, neuroendocrine, and immunomodulatory differences.

Methamphetamine administration targets multiple immune subsets and induces phenotypic alterations suggestive of immunosuppression

Methamphetamine (Meth) is a widely abused stimulant and its users are at increased risk for multiple infectious diseases. To determine the impact of meth on the immune system, we utilized a murine model that simulates the process of meth consumption in a typical addict. Our phenotypic analysis of leukocytes from this dose escalation model revealed that meth affected key immune subsets. Meth administration led to a decrease in abundance of natural killer (NK) cells and the remaining NK cells possessed a phenotype suggesting reduced responsiveness. Dendritic cells (DCs) and Gr-1^high monocytes/macrophages were also decreased in abundance while Gr-1^low monocytes/macrophages appear to show signs of perturbation. CD4 and CD8 T cell subsets were affected by methamphetamine, both showing a reduction in antigen-experienced subsets. CD4 T cells also exhibited signs of activation, with increased expression of CD150 on CD226-expressing cells and an expansion of KLRG1⁺, FoxP3⁻ cells. These results exhibit that meth has the ability to disrupt immune homeostasis and impact key subsets of leukocytes which may leave users more vulnerable to pathogens.

Methamphetamine causes persistent immune dysregulation: a cross-species, translational report

Methamphetamine (MA) dependence causes serious cognitive impairments that can persist during abstinence and negatively affect recovery outcomes. Evidence suggests that immune factors, such as cytokines, chemokines, and cellular adhesion molecules, contribute to MA-induced immune dysfunction, neuronal injury, and persistent cognitive impairments, yet the role of MA-induced brain inflammation remains unclear. To address this question, we used a cross-species, translational approach. Thirty-two male C57BL/6J mice were administered MA (1 mg/kg) or saline subcutaneously for seven consecutive days. Mice were euthanized at 72 h or 3 weeks after the last drug dose, and blood and brain samples were collected. In addition, 20 adults in remission from MA dependence and 20 non-dependent controls completed neuropsychological assessments and a blood draw. Multiplex assays were used to measure cytokine, chemokine, and intercellular adhesion molecule (ICAM-1) expression in mouse and human samples. A number of significant MA-induced changes in neuroimmune factors were observed. Of particular interest were the chemokine monocyte chemoattractant protein 1 (MCP-1) and the cellular adhesion molecule ICAM-1, which were similarly increased in the plasma of MA exposed mice as well as humans. In human participants, MA-induced changes in the cytokine and chemokine milieu were accompanied by increased cognitive impairments. Mice showing MA-induced changes in peripheral immune molecule expression also had significant brain-region specific changes in pro-inflammatory cytokines, chemokines, and ICAM-1. This cross-species, translational study suggests that chronic CNS immune dysregulation may in part contribute to the longlasting neuropsychiatric consequences of MA dependence.

Extraction and purification of a lectin from red kidney bean and preliminary immune function studies of the lectin and four Chinese herbal polysaccharides

Reversed micelles were used to extract lectin from red kidney beans and factors affecting reverse micellar systems (pH value, ionic strength and extraction time) were studied. The optimal conditions were extraction at pH 4–6, back extraction at pH 9–11, ion strength at 0.15 M NaCl, extraction for 4–6 minutes and back extraction for 8 minutes. The reverse micellar system was compared with traditional extraction methods and demonstrated to be a time-saving method for the extraction of red kidney bean lectin. Mitogenic activity of the lectin was reasonably good compared with commercial phytohemagglutinin (extracted from Phaseolus vulgaris) Mitogenic properties of the lectin were enhanced when four Chinese herbal polysaccharides were applied concurrently, among which 50 μg/mL Astragalus mongholicus polysaccharides (APS) with 12.5 μg/mL red kidney bean lectin yielded the highest mitogenic activity and 100 mg/kg/bw APS with 12.5 mg/kg/bw red kidney bean lectin elevated mouse nonspecific immunity.

Methamphetamine increases brain viral load and activates natural killer cells in simian immunodeficiency virus-infected monkeys

Methamphetamine (Meth) abuse increases risky behaviors that contribute to the spread of HIV infection. In addition, because HIV and Meth independently affect physiological systems including the central nervous system, HIV-induced disease may be more severe in drug users. We investigated changes in blood and brain viral load as well as differences in immune cells in chronically simian immunodeficiency virus-infected rhesus macaques that were either administered Meth or used as controls. Although Meth administration did not alter levels of virus in the plasma, viral load in the brain was significantly increased in Meth-treated animals compared with control animals. Meth treatment also resulted in an activation of natural killer cells. Given the prevalence of Meth use in HIV-infected and HIV at-risk populations, these findings reveal the likely untoward effects of Meth abuse in such individuals.

Effects of single or repeated administrations of methamphetamine on immune response in mice

The present study aimed to clarify the connection between immune responses and the administration frequency of methamphetamine (MAP) in male and female mice. Male and female ddY mice were given single or multiple (repeated for 10 days) intraperitoneal injections of MAP (5.0 mg/kg/day). The following immune parameters were examined; the number of leukocytes in peripheral blood and the proliferative activity (phytohemagglutinin;PHA, lipopolysaccharide; LPS response) and natural killer (NK) cell activity in splenic lymphocytes. Further, the differences in metabolic function in the spleen in response to MAP (and its metabolite amphetamine) in male and female mice were measured by gas chromatography. The results of the present study were that; 1) single and repeated MAP injections reduced leukocytes; 2) single MAP injection increased the proliferative response of splenic lymphocytes to PHA stimulation in only male mice, but the response to LPS stimulation was slightly increased in both male and female mice; 3) single and repeated MAP injections reduced NK cell activity of splenic lymphocytes, and especially in female mice with 5 injections of MAP; 4) with 10 MAP injections the NK cell activity and leukocytes recovered to the level of controls; and 5) the metabolic activity of MAP was reduced in female mice treated acutely with MAP in comparison to male mice. These results appear to indicate that immune responses to MAP were involved in the different results shown for administration frequency, sex difference and metabolic process of MAP.