The concomitant use of cannabis and cocaine coexists with increased LPS levels and systemic inflammation in male drug users

Cocaine-Induced Cardiac Alterations: Histological and Immunohistochemical Post-Mortem Analysis

Background: Cocaine abuse represents a serious health issue. The cardiovascular system is one of the main sites on which cocaine elicits its toxicity, as indicated by deadly events mainly related to myocardial infarction. The main aim of this study was to characterize the histological and immunohistochemical alterations related to cocaine abuse in cardiac tissue. Methods: Cardiac tissue samples derived from cocaine-related (n = 30) and not-cocaine-related deaths (n = 30). Histomorphology evaluations and immunohistochemistry for inflammatory biomarkers (CD45 and CD3) have been performed on formalin-fixed, paraffin-embedded (FFPE) cardiac tissue samples. Results: A higher frequency of cardiac alterations, such as wavy fibers, interstitial edema, fibrosis and hemorrhagic extravasation, were found in the group of cocaine users compared to the control group. Moreover, immunohistochemical analysis showed higher levels of inflammatory cells infiltrate within the cocaine-related deaths group. Conclusions: These data could shed new light on the complex relationship between cocaine use and cardiac alterations. Specifically, our data support the evidence that cocaine abuse is related to cardiac inflammation. Therefore, the generation of an inflammatory state could promote functional and structural cardiac alterations and lead ultimately to myocardial infarction. This would explain the high frequency of acute myocardial infarction in cocaine users.

Increased Mortality Risk in Patients with Illicit Substance Use and COVID-19: Analysis of a Large Brazilian Sample

BACKGROUND

Illicit substance use (ISU) may be a potential predisposing factor for severe COVID-19 outcomes.

OBJECTIVE

To conduct a propensity score-matching analysis to assess and compare the mortality rate of individuals who reported ISU among a sizable cohort of hospitalized COVID-19 patients in Brazil.

METHODS

This population-based retrospective cohort study analyzed a nationwide Brazilian database of patients hospitalized for COVID-19. Eligible patients were aged >18 years and tested positive for SARS-CoV-2 infection. The primary exposure of interest was ISU, defined as substances prohibited under Brazilian law, primarily marijuana, cocaine, and crack. Statistical analysis was performed using t-tests, chi-square tests, the Propensity Score Matching (PSM) technique to create a balanced comparison group, and the McNemar test for paired samples to assess mortality risk among patients with ISU.

RESULTS

In a cohort of 2,124,285 patients, 1,845 had ISU. The mortality rate in the ISU group was slightly higher than that in the non-ISU group (33% vs. 32%). After PSM, we found a higher odds ratio for death in patients with ISU (OR 2.18; 95% CI 1.85-2.57; p < 0.001).

CONCLUSION

Our study highlights a significant association between ISU and an increased mortality risk in COVID-19 patients.

Medicinal Cannabis and the Intestinal Microbiome

Historically, the multiple uses of cannabis as a medicine, food, and for recreational purposes as a psychoactive drug span several centuries. The various components of the plant (i.e., seeds, roots, leaves and flowers) have been utilized to alleviate symptoms of inflammation and pain (e.g., osteoarthritis, rheumatoid arthritis), mood disorders such as anxiety, and intestinal problems such as nausea, vomiting, abdominal pain and diarrhea. It has been established that the intestinal microbiota progresses neurological, endocrine, and immunological network effects through the gut-microbiota-brain axis, serving as a bilateral communication pathway between the central and enteric nervous systems. An expanding body of clinical evidence emphasizes that the endocannabinoid system has a fundamental connection in regulating immune responses. This is exemplified by its pivotal role in intestinal metabolic and immunity equilibrium and intestinal barrier integrity. This neuromodulator system responds to internal and external environmental signals while also serving as a homeostatic effector system, participating in a reciprocal association with the intestinal microbiota. We advance an exogenous cannabinoid-intestinal microbiota-endocannabinoid system axis potentiated by the intestinal microbiome and medicinal cannabinoids supporting the mechanism of action of the endocannabinoid system. An integrative medicine model of patient care is advanced that may provide patients with beneficial health outcomes when prescribed medicinal cannabis.

Exploring peripheral biomarkers in psychostimulant use: A systematic review on neurotrophins, stress-related hormones, oxidative stress molecules and genetic factors

BACKGROUND

This systematic review aims to comprehensively explore the impact of psychostimulant substances on neurotrophic and inflammatory pathways, including brain-derived neurotrophic factor (BDNF), pro-BDNF, cortisol, dehydroepiandrosterone sulfate (DHEAS), thiobarbituric acid reactive substances (TBARS), interleukins, and the role of genetic factors. The study seeks to address existing gaps in the literature by providing a thorough evaluation of neurotrophic and inflammatory system alterations associated with different stages of psychostimulant dependence for a more nuanced understanding of substance use disorder (SUD) neurobiology.

METHODS

A systematic review was conducted in PubMed, Scopus, and Web of Science databases following the PRISMA guidelines. The research encompasses 50 studies with a participant pool totaling 6792 individuals using psychostimulant substances.

RESULTS

Key findings include diverse impacts of cocaine on BDNF levels, mainly consisting of their significant increase during withdrawal. In contrast, NGF showed an opposite behavior, reducing during withdrawal. Cortisol and DHEAS levels exhibited relevant increases after psychostimulant use, while TBARS showed conflicting results. Genetic investigations predominantly focused on the Val66Met polymorphism of the BDNF gene, revealing associations with susceptibility to stimulant addiction.

CONCLUSIONS

Neurotrophins and inflammatory molecules play a significant role in the pathophysiological mechanisms following psychostimulant use. A better understanding of their complex interplay could aid clinicians in identifying biomarkers of different disease stages. Moreover, clinical interventions designed to interfere with neurotrophic and inflammatory pathways could possibly lead to craving-modulatory strategies and reduce pathological neuronal and systemic consequences of psychostimulant use.

The impact of psychostimulants on central and peripheral neuro-immune regulation: a scoping review of cytokine profiles and their implications for addiction

It is now well-accepted that psychostimulants act on glial cells causing neuroinflammation and adding to the neurotoxic effects of such substances. Neuroinflammation can be described as an inflammatory response, within the CNS, mediated through several cytokines, reactive oxygen species, chemokines and other inflammatory markers. These inflammatory players, in particular cytokines, play important roles. Several studies have demonstrated that psychostimulants impact on cytokine production and release, both centrally and at the peripheral level. Nevertheless, the available data is often contradictory. Because understanding how cytokines are modulated by psychoactive substances seems crucial to perspective successful therapeutic interventions, here, we conducted a scoping review of the available literature. We have focused on how different psychostimulants impact on the cytokine profile. Publications were grouped according to the substance addressed (methamphetamine, cocaine, methylphenidate, MDMA or other amphetamines), the type of exposure and period of evaluation (acute, short- or long-term exposure, withdrawal, and reinstatement). Studies were further divided in those addressing central cytokines, circulating (peripheral) levels, or both. Our analysis showed that the classical pro-inflammatory cytokines TNF-α, IL-6, and IL-1β were those more investigated. The majority of studies have reported increased levels of these cytokines in the central nervous system after acute or repeated drug. However, studies investigating cytokine levels during withdrawal or reinstatement have shown higher variability in their findings. Although we have identified fewer studies addressing circulating cytokines in humans, the available data suggest that the results may be more robust in animal models than in patients with problematic drug use. As a major conclusion, an extensive use of arrays for relevant cytokines should be considered to better determine which cytokines, upon the classical ones, may be involved in the progression from episodic use to the development of addiction. A concerted effort is still necessary to address the link between peripheral and central immune players, including from a longitudinal perspective. Until there, the identification of new biomarkers and therapeutic targets to envision personalized immune-based therapeutics will continue to be unlikely.

The Inflammatory Signals Associated with Psychosis: Impact of Comorbid Drug Abuse

Psychosis and substance use disorders are two diagnostic categories whose association has been studied for decades. In addition, both psychosis spectrum disorders and drug abuse have recently been linked to multiple pro-inflammatory changes in the central nervous system. We have carried out a narrative review of the literature through a holistic approach. We used PubMed as our search engine. We included in the review all relevant studies looking at pro-inflammatory changes in psychotic disorders and substance use disorders. We found that there are multiple studies that relate various pro-inflammatory lipids and proteins with psychosis and substance use disorders, with an overlap between the two. The main findings involve inflammatory mediators such as cytokines, chemokines, endocannabinoids, eicosanoids, lysophospholipds and/or bacterial products. Many of these findings are present in different phases of psychosis and in substance use disorders such as cannabis, cocaine, methamphetamines, alcohol and nicotine. Psychosis and substance use disorders may have a common origin in an abnormal neurodevelopment caused, among other factors, by a neuroinflammatory process. A possible convergent pathway is that which interrelates the transcriptional factors NFκB and PPARγ. This may have future clinical implications.

Endotoxin tolerance and low activation of TLR-4/NF-κB axis in monocytes of COVID-19 patients

Higher endotoxin in the circulation may indicate a compromised state of host immune response against coinfections in severe COVID-19 patients. We evaluated the inflammatory response of monocytes from COVID-19 patients after lipopolysaccharide (LPS) challenge. Whole blood samples of healthy controls, patients with mild COVID-19, and patients with severe COVID-19 were incubated with LPS for 2 h. Severe COVID-19 patients presented higher LPS and sCD14 levels in the plasma than healthy controls and mild COVID-19 patients. In non-stimulated in vitro condition, severe COVID-19 patients presented higher inflammatory cytokines and PGE-2 levels and CD14 + HLA-DRlow monocytes frequency than controls. Moreover, severe COVID-19 patients presented higher NF-κB p65 phosphorylation in CD14 + HLA-DRlow, as well as higher expression of TLR-4 and NF-κB p65 phosphorylation in CD14 + HLA-DRhigh compared to controls. The stimulation of LPS in whole blood of severe COVID-19 patients leads to lower cytokine production but higher PGE-2 levels compared to controls. Endotoxin challenge with both concentrations reduced the frequency of CD14 + HLA-DRlow in severe COVID-19 patients, but the increases in TLR-4 expression and NF-κB p65 phosphorylation were more pronounced in both CD14 + monocytes of healthy controls and mild COVID-19 patients compared to severe COVID-19 group. We conclude that acute SARS-CoV-2 infection is associated with diminished endotoxin response in monocytes. KEY MESSAGES: Severe COVID-19 patients had higher levels of LPS and systemic IL-6 and TNF-α. Severe COVID-19 patients presented higher CD14+HLA-DRlow monocytes. Increased TLR-4/NF-κB axis was identified in monocytes of severe COVID-19. Blunted production of cytokines after whole blood LPS stimulation in severe COVID-19. Lower TLR-4/NF-κB activation in monocytes after LPS stimulation in severe COVID-19.

C-Reactive Protein (CRP): A Potent Inflammation Biomarker in Psychiatric Disorders

An increasing number of studies have investigated the role of inflammation in psychiatric disorders, by demonstrating how an altered/dysfunctional immunological and inflammatory system may underpin a psychiatric condition. Particularly, several studies specifically investigated the role of a neuroinflammatory biomarker, named C-reactive protein (CRP), in psychiatric disorders. Overall, even though scientific literature so far published still does not appear definitive, CRP is more likely reported to be elevated in several psychiatric disorders, including schizophrenia, mood disorders, anxiety disorders and post-traumatic stress disorder. Moreover, a low-grade inflammation (CRP >3 mg/L) has been more likely observed in a subgroup of patients affected with a more severe psychopathological symptomatology, more treatment resistance and worst clinical mental illness course, strengthening the hypothesis of the need for a different clinical and prognostic characterization based on this concomitant neuroinflammatory predisposition. However, even though further research studies are needed to confirm this preliminary evidence, CRP may represent a potential clinical routine biomarker which could be integrated in the clinical routine practice to better characterize clinical picture and course as well as address clinicians towards a personalized treatment.

Could Alcohol Abuse and Dependence on Junk Foods Inducing Obesity and/or Illicit Drug Use Represent Danger to Liver in Young People with Altered Psychological/Relational Spheres or Emotional Problems?

Recent data show that young people, mainly due to the pressure of some risk factors or due to disrupted interpersonal relationships, utilise greater reward value and display greater sensitivity to the reinforcing properties of "pleasurable stimuli", specifically in those situations in which an enhanced dopamine release is present. Alcoholic beverages, foods rich in sugar and fat, and illicit drug use are pleasurable feelings associated with rewards. Research shows that there is a link between substance abuse and obesity in brain functioning. Still, alcohol excess is central in leading to obesity and obesity-related morbidities, such as hepatic steatosis, mainly when associated with illicit drug dependence and negative eating behaviours in young people. It is ascertained that long-term drinking causes mental damage, similarly to drug abuse, but also affects liver function. Indeed, beyond the pharmacokinetic interactions of alcohol with drugs, occurring in the liver due to the same metabolic enzymes, there are also pharmacodynamic interactions of both substances in the CNS. To complicate matters, an important noxious effect of junk foods consists of inducing obesity and obesity-related NAFLD. In this review, we focus on some key mechanisms underlying the impact of these addictions on the liver, as well as those on the CNS.

Multiple substance use, inflammation and cardiac stretch in women living with HIV

BACKGROUND

Cardiovascular disease (CVD) and heart failure (HF) are disproportionately high in people living with HIV and differ by sex. Few CVD-related studies focus on drug use, yet it is common in low-income women living with HIV (WLWH) and increases cardiac dysfunction.

SETTING

We recruited unsheltered and unstably housed WLWH from San Francisco community venues to participate in a six-month cohort study investigating linkages between drug use, inflammation, and cardiac dysfunction.

METHODS

Adjusting for CVD risk factors, co-infections, medications, and menopause, we examined the effects of toxicology-confirmed drug use and inflammation (C-reactive protein, sCD14, sCD163 and sTNFR2) on levels of NT-proBNP, a biomarker of cardiac stretch and HF.

RESULTS

Among 74 WLWH, the median age was 53 years and 45 % were Black. At baseline, 72 % of participants had hypertension. Substances used included tobacco (65 %), cannabis (53 %), cocaine (49 %), methamphetamine (31 %), alcohol (28 %), and opioids (20 %). Factors significantly associated with NT-proBNP included cannabis use (Adjusted Relative Effect [ARE]: -39.6 %) and sTNFR2 (ARE: 65.5 %). Adjusting for heart failure and restricting analyses to virally suppressed persons did not diminish effects appreciably. Cannabis use was not significantly associated with sTNFR2 and did not change the association between sTNFR2 and NT-proBNP.

CONCLUSIONS

Among polysubstance-using WLWH, NT-proBNP levels signaling cardiac stretch were positively associated with sTNFR2, but 40 % lower in people who used cannabis. Whether results suggest that cardiovascular pathways associated with cannabis use mitigate cardiac stress and dysfunction independent of inflammation in WLWH who use multiple substances merits further investigation.

Inflammatory Biomarkers in Addictive Disorders

Substance use disorders are a group of diseases that are associated with social, professional, and family impairment and that represent a high socio-economic impact on the health systems of countries around the world. These disorders present a very complex diagnosis and treatment regimen due to the lack of suitable biomarkers supporting the correct diagnosis and classification and the difficulty of selecting effective therapies. Over the last few years, several studies have pointed out that these addictive disorders are associated with systemic and central nervous system inflammation, which could play a relevant role in the onset and progression of these diseases. Therefore, identifying different immune system components as biomarkers of such addictive disorders could be a crucial step to promote appropriate diagnosis and treatment. Thus, this work aims to provide an overview of the immune system alterations that may be biomarkers of various addictive disorders.