Immune and glial cell alterations in the rat brain after repeated exposure to the synthetic cannabinoid JWH-018.

The use of synthetic cannabinoid receptor agonists (SCRAs) poses major psychiatric risks. We previously showed that repeated exposure to the prototypical SCRA JWH-018 induces alterations in dopamine (DA) transmission, abnormalities in the emotional state, and glial cell activation in the mesocorticolimbic DA circuits of rats. Despite growing evidence suggesting the relationship between substance use disorders (SUD) and neuroinflammation, little is known about the impact of SCRAs on the neuroimmune system. Here, we investigated whether repeated JWH-018 exposure altered neuroimmune signaling, which could be linked with previously reported central effects. Adult male Sprague-Dawley (SD) rats were exposed to JWH-018 (0.25 mg/kg, i.p.) for fourteen consecutive days, and the expression of cytokines, chemokines, and growth factors was measured seven days after treatment discontinuation in the striatum, cortex, and hippocampus. Moreover, microglial (ionized calcium-binding adaptor molecule 1, IBA-1) and astrocyte (glial fibrillary acidic protein, GFAP) activation markers were evaluated in the caudate-putamen (CPu). Repeated JWH-018 exposure induces a perturbation of neuroimmune signaling specifically in the striatum, as shown by increased levels of cytokines [interleukins (IL) -2, -4, -12p70, -13, interferon (IFN) γ], chemokines [macrophage inflammatory protein (MIP) -1α, -3α], and growth factors [macrophage colony-stimulating factor (M-CSF), vascular endothelial growth factor (VEGF)], together with increased IBA-1 and GFAP expression in the CPu. JWH-018 exposure induces persistant brain region-specific immune alterations up to seven days after drug discontinuation, which may contribute to the behavioral and neurochemical dysregulations in striatal areas that play a role in the reward-related processes that are frequently impaired in SUD.

Neuroticism, depressive symptoms, and serum BDNF.

OBJECTIVE: Animal models and clinical studies suggest that brain-derived neurotrophic factor (BDNF) is involved in the pathophysiology of depression. We test whether serum and plasma levels of BDNF are associated with trait neuroticism and its facets and with state measures of depressive symptoms. METHODS: In a community-based cohort (N = 2099), we measured serum and plasma BDNF concentrations and administered the Revised NEO Personality Inventory and the Center for Epidemiological Studies Depression Scale. Covariates included age, sex, cigarette smoking, obesity, and antidepressant use. RESULTS: Serum BDNF concentrations were inversely related to neuroticism (r = -0.074, p < .001), in particular the depression facet (r = -0.08, p < .001). Lower BDNF concentrations were also associated with severe depressive symptoms (Center for Epidemiological Studies Depression Scale ≥ 28; odds ratio = 0.906; 95% confidence interval = 0.851-0.965). The association of serum BDNF with neuroticism was independent of depressive symptoms, indicating that serum BDNF might represent a biological correlate of neuroticism and not just of transient depressive states. Plasma BDNF was not associated with measures of depression. CONCLUSIONS: Our study suggests that lower serum BDNF is associated with both a dispositional vulnerability to depression and acute depressive states in the general population.

Independent and additive effects of cytokine patterns and the metabolic syndrome on arterial aging in the SardiNIA Study.

OBJECTIVE: Metabolic syndrome (MetS) and its components accelerate age-associated increases in arterial stiffness and thickness. We investigated whether specific proinflammatory cytokines contribute to arterial aging, independent of age, sex, MetS, and other traditional CV risk factors. RESEARCH DESIGN AND METHODS: MetS components (ATP III criteria) and arterial properties were assessed in 6148 subjects, aged 14-102 in Sardinia, Italy. Common carotid artery (CCA) diameter, intima-media thickness (IMT), and aortic pulse wave velocity (PWV), adiponectin, leptin, high-sensitivity C reactive protein (hsCRP), monocyte chemoattractant protein 1 (MCP1), and interleukin 6 (IL6) were measured. RESULTS: While cytokine levels - except for MCP1 - were significantly higher (lower for adiponectin) in MetS than in control subjects, and the increased PWV and CCA IMT with aging were associated with MetS, this association was independent of cytokine levels (p<0.001 for both PWV and CCA IMT). Specific cytokines, however, were significantly associated with arterial stiffness (higher leptin, p<0.001, and higher hsCRP, p<0.001) or thickness (lower adiponectin, p<0.05, and higher IL6, p<0.001) - independent of age, sex, MetS and other traditional CV risk factors. The co-occurrence of both MetS and higher cytokines levels was associated with greater increases in arterial stiffness and thickness. CONCLUSION: While MetS and specific cytokine patterns associated with arterial aging, the increases in arterial stiffness and thickness are greater when both MetS and higher cytokine levels are present, suggesting a possible synergistic effect of MetS and inflammation on the arterial wall.

Genome-wide association study of vitamin B6, vitamin B12, folate, and homocysteine blood concentrations.

The B vitamins are components of one-carbon metabolism (OCM) that contribute to DNA synthesis and methylation. Homocysteine, a by-product of OCM, has been associated with coronary heart disease, stroke and neurological disease. To investigate genetic factors that affect circulating vitamin B6, vitamin B12, folate and homocysteine, a genome-wide association analysis was conducted in the InCHIANTI (N = 1175), SardiNIA (N = 1115), and BLSA (N = 640) studies. The top loci were replicated in an independent sample of 687 participants in the Progetto Nutrizione study. Polymorphisms in the ALPL gene (rs4654748, p = 8.30 x 10(-18)) were associated with vitamin B6 and FUT2 (rs602662, [corrected] p = 2.83 x 10(-20)) with vitamin B12 serum levels. The association of MTHFR, a gene consistently associated with homocysteine, was confirmed in this meta-analysis. The ALPL gene likely influences the catabolism of vitamin B6 while FUT2 interferes with absorption of vitamin B12. These findings highlight mechanisms that affect vitamin B6, vitamin B12 and homocysteine serum levels.

Phosphodiesterase 8B gene variants are associated with serum TSH levels and thyroid function.

Thyroid-stimulating hormone (TSH) controls thyroid growth and hormone secretion through binding to its G protein-coupled receptor (TSHR) and production of cyclic AMP (cAMP). Serum TSH is a sensitive indicator of thyroid function, and overt abnormalities in thyroid function lead to common endocrine disorders affecting approximately 10% of individuals over a life span. By genotyping 362,129 SNPs in 4,300 Sardinians, we identified a strong association (p = 1.3 x 10(-11)) between alleles of rs4704397 and circulating TSH levels; each additional copy of the minor A allele was associated with an increase of 0.13 muIU/ml in TSH. The single-nucleotide polymorphism (SNP) is located in intron 1 of PDE8B, encoding a high-affinity cAMP-specific phosphodiesterase. The association was replicated in 4,158 individuals, including additional Sardinians and two genetically distant cohorts from Tuscany and the Old Order Amish (overall p value = 1.9 x 10(-20)). In addition to association of TSH levels with SNPs in PDE8B, our genome scan provided evidence for association with PDE10A and several biologically interesting candidates in a focused analysis of 24 genes. In particular, we found evidence for association of TSH levels with SNPs in the THRB (rs1505287, p = 7.3 x 10(-5)), GNAQ (rs10512065, p = 2.0 x 10(-4)), TG (rs2252696, p = 2.2 x 10(-3)), POU1F1 (rs1976324, p = 3.9 x 10(-3)), PDE4D (rs27178, p = 8.3 x 10(-3)), and TSHR (rs4903957, p = 8.6 x 10(-3)) loci. Overall, the results suggest a primary effect of PDE8B variants on cAMP levels in the thyroid. This would affect production of T4 and T3 and feedback to alter TSH release by the pituitary. PDE8B may thus provide a candidate target for the treatment of thyroid dysfunction.