Cigarette and Cannabis Smoking Effects on GPR15+ Helper T Cell Levels in Peripheral Blood: Relationships with Epigenetic Biomarkers

Epigenetic effects of cannabis: A systematic scoping review of behavioral and emotional symptoms associated with cannabis use and exocannabinoid exposure

BACKGROUND

Recent research suggests that epigenetic modifications may mediate the behavioral effects of cannabis, influencing exocannabinnoids' long term effects in cognitive function and its role in the emergence of psychotic symptoms.

BASIC PROCEDURES

In this systematic scoping review, we assessed the current evidence of epigenetic effects associated with the use of cannabis or exocannabinoid administration and their relationship with behavioral and emotional symptoms. We searched PubMed, Cochrane CENTRAL, and Web of Science, up to January 2022, using the terms "cannabis" and "epigenetics." The search yielded 178 articles, of which 43 underwent full article revision; 37 articles were included in the review.

MAIN FINDINGS

The gathered evidence included observational cross-sectional studies conducted on human subjects and experimental designs using animal models that conveyed disparity in administration dosage, methods of cannabis use assessment and targeted epigenetic mechanisms. Nine studies performed epigenome-wide analysis with identification of differentially methylated sites; most of these studies found a global hypomethylation, and enrichment in genes related to cellular survival and neurodevelopment. Other studies assessed methylation at specific genes and found that cannabis exposure was associated with reduced methylation at Cg05575921, DNMT1, DRD2, COMT, DLGAP2, Arg1, STAT3, MGMT, and PENK, while hypermethylation was found at DNMT3a/b, NCAM1, and AKT1.

CONCLUSIONS

The review found evidence of an exocannabinoid-induced epigenetic changes that modulate depressive-anxious, psychotic, and addictive behavioural phenotypes. Further studies will require dosage exposure/administration uniformization and a customized pool of genes to assess their suitability as biomarkers for psychiatric diseases.

A Transcriptomic Analysis of Smoking-Induced Gene Expression Alterations in Coronary Artery Disease Patients

Smoking is a well established risk factor for coronary artery disease (CAD). Despite this, there have been no previous studies investigating the effects of smoking on blood gene expression in CAD patients. This single-centre cross-sectional study was designed with clearly defined inclusion criteria to address this gap. We conducted a high-throughput approach using next generation sequencing analysis with a single-end sequencing protocol and a read length of 75-cycles. Sixty-one patients with a median age of 67 years (range: 28-88 years) were recruited, and only 44 subjects were included for further analyses. Our investigation revealed 120 differentially expressed genes (DEGs) between smokers and nonsmokers, with a fold change (FC) of ≥1.5 and a p-value < 0.05. Among these DEGs, 15 were upregulated and 105 were downregulated. Notably, when applying a more stringent adjusted FC ≥ 2.0, 31 DEGs (5 upregulated, annotated to immune response pathways, and 26 downregulated, involving oxygen and haem binding or activity, with FDR ≤ 0.03) remained statistically significant at an alpha level of <0.05. Our results illuminate the molecular mechanisms underlying CAD, fortifying existing epidemiological evidence. Of particular interest is the unexplored overexpression of RCAN3, TRAV4, and JCHAIN genes, which may hold promising implications for the involvement of these genes in CAD among smokers.

Emerging roles of a chemoattractant receptor GPR15 and ligands in pathophysiology

Chemokine receptors play a central role in the maintenance of immune homeostasis and development of inflammation by directing leukocyte migration to tissues. GPR15 is a G protein-coupled receptor (GPCR) that was initially known as a co-receptor for human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV), with structural similarity to other members of the chemoattractant receptor family. Since the discovery of its novel function as a colon-homing receptor of T cells in mice a decade ago, GPR15 has been rapidly gaining attention for its involvement in a variety of inflammatory and immune disorders. The recent identification of its natural ligand C10orf99, a chemokine-like polypeptide strongly expressed in gastrointestinal tissues, has established that GPR15-C10orf99 is a novel signaling axis that controls intestinal homeostasis and inflammation through the migration of immune cells. In addition, it has been demonstrated that C10orf99-independent functions of GPR15 and GPR15-independent activities of C10orf99 also play significant roles in the pathophysiology. Therefore, GPR15 and its ligands are potential therapeutic targets. To provide a basis for the future development of GPR15- or GPR15 ligand-targeted therapeutics, we have summarized the latest advances in the role of GPR15 and its ligands in human diseases as well as the molecular mechanisms that regulate GPR15 expression and functions.

The Use of Cannabinoids in the Treatment of Inflammatory Bowel Disease (IBD): A Review of the Literature

Around the world, about 15 to 40% of individuals with inflammatory bowel disease (IBD) rely on cannabis and cannabinoids to reduce the need for other medications, as well as increase appetite and reduce pain. Whereas more and more patients continue to report benefits accruing from cannabis and cannabinoid usage in IBD, agreement relative to the use of cannabis and its derivatives in IBD remains unclear. This paper reviewed the interplay between cannabinoid use and IBD disease treatment, remission, or symptom relief. The study was conducted from a systematic review perspective. It involved consulting literature from published original research articles, noting outcomes, and performing a meta-analysis to identify trends and draw conclusions. The selected articles were those that had been published in a 10-year period ranging between 2012 and 2022. The motivation was to ensure recency and also relevance to contemporary scientific research and clinical environment practices. Indeed, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework helped in answering the focal question of the investigation, which revolved around whether cannabinoids are beneficial to IBD treatment and to what extent. The aim of using this protocol was to ensure the satisfaction of the article exclusion and inclusion criteria, as well as ensure the utilization of articles directly contributing to the central subject under investigation. In the findings, it was established that on the one hand, cannabinoid usage in IBD treatment comes with promising results as reported in the majority of the selected studies which reported reduced clinical complications which were assessed using Mayo scores, Crohn's Disease Activity Index (CDAI) score, weight gain, enhanced patient health perception, Lichtiger Index and Harvey-Bradshaw Index or general wellbeing. On the other hand, cannabinoid use remains questionable because evidence of high quality is yet to surface vividly, especially in terms of the mode of administration and the appropriate dose. It is also notable that the findings were characterized by a state of high heterogeneity in terms of the study designs of the studies that were selected, disease activity indices, the duration of treatment by different scholarly researchers, the difference in the modes of administration of cannabinoid and cannabis by different researchers, variations in cannabis dosage, differences in the selected studies' inclusion criteria, and variations in their case definitions. The implication is that whereas the efficacy of cannabinoid use in IBD treatment was reported in most studies, outcome generalizability from the review was highly likely to be restricted. In the future, it is recommended that randomized controlled trials center, set universal parameters for IBD treatment using cannabis and cannabinoids to determine intervention safety and effectiveness as well as having homogenous outcomes that can be compared between different studies. In so doing, the appropriate dose and ideal mode of administration of cannabis and its derivatives might be discerned, ensuring relevance based on patient characteristics such as gender and age, as well as the appropriate administration mode and dose as per IBD symptom severity.

Inflammatory and Oxidative Stress Biomarkers in the Elderly, the Birjand Longitudinal Aging Study

Cigarette smoking is a significant risk factor for chronic and atherosclerotic vascular disease that causes preventable considerable morbidity and mortality worldwide. This study is aimed at comparing inflammation and the levels of oxidative stress biomarkers in elderly subjects. The authors recruited the participants (1281 older adults) from the Birjand Longitudinal of Aging study. They measured oxidative stress and inflammatory biomarkers serum levels in the 101 cigarettes and 1180 nonsmokers. The mean age of smokers was 69.3 ± 7.95 years, and most were male. The most percentage of male cigarette smokers have lower body mass index (BMI) (≤19 kg/m²). Females have higher BMI categories than males (P ≤ 0.001). The percentage of diseases and defects was different between cigarette and non-cigarette smoker adults (P ≤ 0.01 to P ≤ 0.001). The total white blood cells, neutrophils, and eosinophils were significantly higher in cigarettes compared to non-cigarette smokers (P ≤ 0.001). Besides, cigarette consumers' percentage of hemoglobin and hematocrit compared to other aged people was significantly different (P ≤ 0.001). However, biomarkers of oxidative stress and antioxidant levels were not significant differences between the two senior groups. Cigarette smoking in older adults was associated with increased inflammatory biomarkers and cells, but it did not find a significant difference in oxidative stress markers. Longitudinal prospective studies may help illuminate the mechanisms inducing oxidative stress and inflammation due to cigarette smoking in each gender.

Elevated Expression and Activation of GPR15 in Immune Cells in Graves' Disease

GPR15 plays an important role in lymphocyte homing and is a key immune molecule to maintain organ immune homeostasis. Yet, no study on the association between GPR15 and Graves' disease (GD) is available. In this study, we systematically investigated the expression of GPR15 in different types of immune cells and different tissues of GD patients. We found that the expressions of GPR15 and GPR15L in peripheral blood of GD patients were increased compared with those in healthy controls. A flow cytometry analysis showed that GPR15 positive cells were mainly CD14+ monocytes and CD56+ natural killer cells (NK cells) of innate immunity, T helper cells and cytotoxic T cells of adaptive immunity. We also found that the expressions of GPR15 and GPR15L in the PBMC of GD patients were positively correlated with the Tfh-specific cytokines IL21 and IL4. In addition, immunohistochemistry showed that the level of GPR15 in thyroid tissue of GD patients was higher than that of the control group. Our results demonstrate for the first time that GPR15 is highly expressed in various immune cells in GD patients, suggesting that GPR15-GPR15L is associated with the activation and infiltration of proinflammatory immune cells in the thyroid tissue of GD patients.

Hemp-Derived Nanovesicles Protect Leaky Gut and Liver Injury in Dextran Sodium Sulfate-Induced Colitis

Hemp (Cannabis sativa L.) is used for medicinal purposes owing to its anti-inflammatory and antioxidant activities. We evaluated the protective effect of nanovesicles isolated from hemp plant parts (root, seed, hemp sprout, and leaf) in dextran sulfate sodium (DSS)-induced colitis in mice. The particle sizes of root-derived nanovesicles (RNVs), seed-derived nanovesicles (SNVs), hemp sprout-derived nanovesicles (HSNVs), and leaf-derived nanovesicles (LNVs) were within the range of 100–200 nm as measured by nanoparticle tracking analysis. Acute colitis was induced in C57BL/N mice by 5% DSS in water provided for 7 days. RNVs were administered orally once a day, leading to the recovery of both the small intestine and colon lengths. RNVs, SNVs, and HSNVs restored the tight (ZO-1, claudin-4, occludin) and adherent junctions (E-cadherin and α-tubulin) in DSS-induced small intestine and colon injury. Additionally, RNVs markedly reduced NF-κB activation and oxidative stress proteins in DSS-induced small intestine and colon injury. Tight junction protein expression and epithelial cell permeability were elevated in RNV-, SNV-, and HSNV-treated T84 colon cells exposed to 2% DSS. Interestedly, RNVs, SNVs, HSNVs, and LNVs reduced ALT activity and liver regeneration marker proteins in DSS-induced liver injury. These results showed for the first time that hemp-derived nanovesicles (HNVs) exhibited a protective effect on DSS-induced gut leaky and liver injury through the gut–liver axis by inhibiting oxidative stress marker proteins.

Impact of the Exposome on the Epigenome in Inflammatory Bowel Disease Patients and Animal Models

Inflammatory bowel diseases (IBD) are chronic inflammatory disorders of the gastrointestinal tract that encompass two main phenotypes, namely Crohn's disease and ulcerative colitis. These conditions occur in genetically predisposed individuals in response to environmental factors. Epigenetics, acting by DNA methylation, post-translational histones modifications or by non-coding RNAs, could explain how the exposome (or all environmental influences over the life course, from conception to death) could influence the gene expression to contribute to intestinal inflammation. We performed a scoping search using Medline to identify all the elements of the exposome that may play a role in intestinal inflammation through epigenetic modifications, as well as the underlying mechanisms. The environmental factors epigenetically influencing the occurrence of intestinal inflammation are the maternal lifestyle (mainly diet, the occurrence of infection during pregnancy and smoking); breastfeeding; microbiota; diet (including a low-fiber diet, high-fat diet and deficiency in micronutrients); smoking habits, vitamin D and drugs (e.g., IBD treatments, antibiotics and probiotics). Influenced by both microbiota and diet, short-chain fatty acids are gut microbiota-derived metabolites resulting from the anaerobic fermentation of non-digestible dietary fibers, playing an epigenetically mediated role in the integrity of the epithelial barrier and in the defense against invading microorganisms. Although the impact of some environmental factors has been identified, the exposome-induced epimutations in IBD remain a largely underexplored field. How these environmental exposures induce epigenetic modifications (in terms of duration, frequency and the timing at which they occur) and how other environmental factors associated with IBD modulate epigenetics deserve to be further investigated.

Effects of Smoking on Inflammatory-Related Cytokine Levels in Human Serum

Cardiovascular and respiratory diseases, and several cancers resulting from tobacco smoking, are initially characterized by chronic systemic inflammation. Cytokine imbalances can result in inflammation, making it important to understand the pathological mechanisms behind cytokine production. In this study, we collected blood samples from 78 healthy male volunteers, including non-smokers (n = 30), current smokers (n = 30), and ex-smokers (n = 18), and utilized the liquid suspension chip technique to investigate and compare the expression levels of 17 cytokines and chemokines in the human serum of these volunteers. The results demonstrated that the expression levels of CXCL9/MIG and sIL-6R significantly increased after smoking, and continued to increase after quitting smoking. The expression levels of TARC, ITAC, and sVEGFR-3 increased after smoking but decreased after quitting smoking; the expression level of SAA significantly decreased after smoking and showed an upward trend after quitting smoking. Seven cytokines (IL-1β, BCA-1, TNF-α, CRP, ENA-78, MDC, and TNFRII) did not vary between the three groups, while four cytokines (IL-1α, IL-6, IL-8, and SCF) were not detected in any serum sample. In conclusion, this study assessed the physiological production of cytokines and chemokines, highlighting the differences in each due to smoking status. Our results could help evaluate the early development of smoking-related chronic diseases and cancers.

Intervention effects on self-control decrease speed of biological aging mediated by changes in substance use: A longitudinal study of African American youth

Biological aging is a common root for multiple diseases causing morbidity and mortality, and trajectories of aging may start early in life. This study was designed to examine whether a universal family-based substance use preventive intervention to enhance self-control and reduce substance use would also result in reductions in biological aging among Black youth from the rural South. The Adults in the Making (AIM) program is a randomized controlled trial with six 2-h sessions for Black youth. The 216 youths agreeing to provide blood at age 22 included 114 who had received the AIM intervention and 102 who assigned to the control group. We examined accelerated DNA methylation (DNAm)-based aging using a recently developed measure, "GrimAge," that has been shown to predict the risk of early mortality and that is known to be more strongly affected by substance use than other DNAm-based aging indices. Relative to those randomly assigned to the control group, those receiving the intervention demonstrated significantly enhanced self-control, slower increases in substance use, and reduced Grim aging at age 22. Using a bootstrapping method with 1000 replications, we found a significant indirect effect of AIM on reduced Grim aging through its effect on self-control and substance use. Sensitivity analyses examined effects using other indices of DNAm-based aging. These findings suggest that a family-based program designed to enhance rural Black youth's self-control can have beneficial effects on self-control, enhancing young adult health and health behavior, and ultimately decreased mortality risk.

The Role of GPR15 Function in Blood and Vasculature

Since the first prominent description of the orphan G protein-coupled receptor 15 (GPR15) on lymphocytes as a co-receptor for the human immunodeficiency virus (HIV) type 1 and 2 and the first report about the GPR15-triggered cytoprotective effect on vascular endothelial cells by recombinant human thrombomodulin, several decades passed before the GPR15 has been recently deorphanized. Because of new findings on GPR15, this review will summarize the consequences of GPR15 signaling considering the variety of GPR15-expressing cell types and of GPR15 ligands, with a focus on blood and vasculature.

Dysregulated epigenetic modifications in psoriasis

The observed incidence of psoriasis has been gradually increasing over time (J Am Acad Dermatol, 03, 2009, 394), but the underlying pathogenic factors have remained unclear. Recent studies suggest the importance of epigenetic modification in the pathogenesis of psoriasis. Aberrant epigenetic patterns including changes in DNA methylation, histone modifications and non-coding RNA expression are observed in psoriatic skin. Reversing these epigenetic mechanisms has showed improvement in psoriatic phenotypes, making epigenetic therapy a potential avenue for psoriasis treatment. Here, we summarize relevant evidence for epigenetic dysregulation contributing to psoriasis susceptibility and pathogenesis, and the factors responsible for epigenetic modifications, providing directions for potential future clinical avenues.

Cannabis and Canabidinoids on the Inflammatory Bowel Diseases: Going Beyond Misuse

Inflammatory bowel diseases (IBD) are characterized by a chronic and recurrent gastrointestinal condition, including mainly ulcerative colitis (UC) and Crohn’s disease (CD). Cannabis sativa (CS) is widely used for medicinal, recreational, and religious purposes. The most studied compound of CS is tetrahydrocannabinol (THC) and cannabidiol (CBD). Besides many relevant therapeutic roles such as anti-inflammatory and antioxidant properties, there is still much controversy about the consumption of this plant since the misuse can lead to serious health problems. Because of these reasons, the aim of this review is to investigate the effects of CS on the treatment of UC and CD. The literature search was performed in PubMed/Medline, PMC, EMBASE, and Cochrane databases. The use of CS leads to the improvement of UC and CD scores and quality of life. The medical use of CS is on the rise. Although the literature shows relevant antioxidant and anti-inflammatory effects that could improve UC and CD scores, it is still not possible to establish a treatment criterion since the studies have no standardization regarding the variety and part of the plant that is used, route of administration and doses. Therefore, we suggest caution in the use of CS in the therapeutic approach of IBD until clinical trials with standardization and a relevant number of patients are performed.

The Effect of Tobacco Smoking Differs across Indices of DNA Methylation-Based Aging in an African American Sample: DNA Methylation-Based Indices of Smoking Capture These Effects

Smoking is one of the leading preventable causes of morbidity and mortality worldwide, prompting interest in its association with DNA methylation-based measures of biological aging. Considerable progress has been made in developing DNA methylation-based measures that correspond to self-reported smoking status. In addition, assessment of DNA methylation-based aging has been expanded to better capture individual differences in risk for morbidity and mortality. Untested to date, however, is whether smoking is similarly related to older and newer indices of DNA methylation-based aging, and whether DNA methylation-based indices of smoking can be used in lieu of self-reported smoking to examine effects on DNA methylation-based aging measures. In the current investigation we examine mediation of the impact of self-reported cigarette consumption on accelerated, intrinsic DNA methylation-based aging using indices designed to predict chronological aging, phenotypic aging, and mortality risk, as well as a newly developed DNA methylation-based measure of telomere length. Using a sample of 500 African American middle aged smokers and non-smokers, we found that a) self-reported cigarette consumption was associated with accelerated intrinsic DNA methylation-based aging on some but not all DNA methylation-based aging indices, b) for those aging outcomes associated with self-reported cigarette consumption, DNA methylation-based indicators of smoking typically accounted for greater variance than did self-reported cigarette consumption, and c) self-reported cigarette consumption effects on DNA methylation-based aging indices typically were fully mediated by DNA methylation-based indicators of smoking (e.g., PACKYRS from GrimAge; or cg05575921 CpG site). Results suggest that when DNA methylation-based indices of smoking are substituted for self-reported assessments of smoking, they will typically fully reflect the varied impact of cigarette smoking on intrinsic, accelerated DNA methylation-based aging.