Immuno-metabolic profile of patients with psychotic disorders and metabolic syndrome. Results from the FACE-SZ cohort

Background: Metabolic syndrome (MetS) is a highly prevalent and harmful medical disorder often comorbid with psychosis where it can contribute to cardiovascular complications. As immune dysfunction is a key shared component of both MetS and schizophrenia (SZ), this study investigated the relationship between immune alterations and MetS in patients with SZ, whilst controlling the impact of confounding clinical characteristics including psychiatric symptoms and comorbidities, history of childhood maltreatment and psychotropic treatments. Method: A total of 310 patients meeting DSM-IV criteria for SZ or schizoaffective disorders (SZA), with or without MetS, were systematically assessed and included in the FondaMental Advanced Centers of Expertise for Schizophrenia (FACE-SZ) cohort. Detailed clinical characteristics of patients, including psychotic symptomatology, psychiatric comorbidities and history of childhood maltreatment were recorded and the serum levels of 18 cytokines were measured. A penalized regression method was performed to analyze associations between inflammation and MetS, whilst controlling for confounding factors. Results: Of the total sample, 25% of patients had MetS. Eight cytokines were above the lower limit of detection (LLOD) in more than 90% of the samples and retained in downstream analysis. Using a conservative Variable Inclusion Probability (VIP) of 75%, we found that elevated levels of interleukin (IL)-6, IL-7, IL-12/23 p40 and IL-16 and lower levels of tumor necrosis factor (TNF)-α were associated with MetS. As for clinical variables, age, sex, body mass index (BMI), diagnosis of SZ (not SZA), age at the first episode of psychosis (FEP), alcohol abuse, current tobacco smoking, and treatment with antidepressants and anxiolytics were all associated with MetS. Conclusion: We have identified five cytokines associated with MetS in SZ suggesting that patients with psychotic disorders and MetS are characterized by a specific “immuno-metabolic” profile. This may help to design tailored treatments for this subgroup of patients with both psychotic disorders and MetS, taking one more step towards precision medicine in psychiatry. © 2022 The AuthorsImmuno-Génétique, Inflammation, retro-Virus, Environnement : de l'étiopathogénie des troubles psychotiques aux modèles animauxRéseau d'Innovation sur les Voies de Signalisation en Sciences de la Vi

The upregulating effect of dexamethasone on tumor necrosis factor production is mediated by a nitric oxide-producing cytochrome P450

: Dexamethasone (DEX) is a well-known inhibitor of tumor necrosis factor (TNF) production when given shortly before lipopolysaccharide (LPS). However, DEX (10 mg/kg, ip) potentiates TNF production when administered 24-48 hr before LPS (16 micrograms/kg, ip). We have found that this is probably due to DEX induction of cytochrome P450 3A, which is known to produce nitric oxide (NO). The upregulating effect of DEX on TNF production is associated with increased NO production. Both the upregulation of NO and of TNF production by DEX are inhibited by co-administration of the P450 3A inhibitor troleandomycin (TAO, 40 mg/kg, ip). These data suggest that P450 3A-generated NO might be involved in TNF induction

Chlorpromazine inhibits nitric oxide-mediated increase in intracellular cGMP in a mouse teratocarcinoma cell line

: Chlorpromazine is a phenothiazine with a structure similar to that of methylene blue. Since methylene blue is a well known inhibitor of nitric oxide-induced cyclic GMP accumulation, we investigated whether chlorpromazine had the same effect. Cyclic GMP accumulation, induced in a mouse teratocarcinoma cell line (P19) by sodium nitroprusside (a nitric oxide releasing agent), was inhibited by both methylene blue (IC50 0.34 microM) and chlorpromazine (IC50 35 microM). Chlorpromazine's action was probably directed specifically at soluble guanylate cyclase, since the drug had no effect on ADP-ribosylation in rat hippocampus, another nitric oxide-affected, but cGMP-independent event

Endogenous nitric oxide production by human monocytic cells regulates LPS-induced TNF production

: The ability to produce nitric oxide (NO) of human monocytes macrophages is object of debate. While studying the regulation of tumor necrosis factor (TNF) synthesis induced by endotoxin (LPS) in a human cell line of monocyte origin (THP-1) and in human peripheral blood mononuclear cells (PBMC) we found an indirect evidence of such production. We showed that L-N-monomethyl-arginine (L-NMMA), an inhibitor of NO synthase, and hemoglobin, a chelator of NO, are able to significantly reduce TNF synthesis, indicating that NO production is induced by LPS and contributes to the induction of TNF. Since NO is a known cytostatic agent, we also studied the cytostatic effect of LPS, and demonstrated that it is reverted by L-NMMA. Although we were unable to show any nitrites/nitrates accumulation in the culture media, taken together our data give an indirect evidence of a physiologically relevant LPS-induced NO production in human monocytes-macrophages

A glucocorticoid receptor-independent mechanism for neurosteroid inhibition of tumor necrosis factor production

: We investigated the effect of two neurosteroids, pregnenolone and dehydroepiandrosterone sulfate on lipopolysaccharide-induced tumor necrosis factor (TNF) production in vivo and in vitro. Dehydroepiandrosterone sulfate (0.3-30 mg/kg, i.p.) inhibited serum TNF induced by lipopolysaccharide (2.5 micrograms/mouse, i.p.), without affecting the induction of serum corticosterone. Intracerebroventricular (i.c.v.) administration of dehydroepiandrosterone sulfate (0.2-5 micrograms/mouse) also inhibited brain TNF induced by i.c.v. lipopolysaccharide (2.5 micrograms/mouse). Dehydroepiandrosterone sulfate and pregnenolone (10(-6)-10(-4) M) inhibited TNF production in vitro by lipopolysaccharide-stimulated human peripheral blood mononuclear cells or by the human THP-1 cell line, suggesting that this action might also be relevant in humans. We obtained two lines of evidence that neurosteroids do not inhibit TNF via the glucocorticoid receptor. (1) Dehydroepiandrosterone sulfate and pregnenolone did not activate the alpha 1-acid glycoprotein promoter, a typical effect of glucocorticoids mediated by the glucocorticoid receptor, while strong activation of this promoter was observed with dexamethasone. (2) The inhibitory effect of dehydroepiandrosterone sulfate and pregnenolone on TNF production was not reversed by the glucocorticoid receptor antagonist, mifepristone (RU38486). On the contrary the inhibitory effect of dexamethasone, a classical glucocorticoid and inhibitor of TNF synthesis, was completely reversed by RU38486

Chlorpromazine inhibits tumour necrosis factor synthesis and cytotoxicity in vitro

: Chlorpromazine (CPZ) has been previously shown to protect against endotoxin [lipopolysaccharide (LPS)] lethality and inhibit the release of tumour necrosis factor in vivo. We investigated at the cellular level whether this was due to direct inhibition of tumour necrosis factor-alpha (TNF-alpha) synthesis, using LPS-stimulated THP-1 human monocytic leukemia cells. We also studied the effect of CPZ on human TNF-alpha action by assessing TNF-alpha cytotoxicity on mouse fibrosarcoma L929 cells. CPZ (1-100 microM) inhibited TNF-alpha production in THP-1 cells in a dose dependent manner by a maximum of 80%. This effect was comparable to that of two well-known inhibitory drugs, dexamethasone and cyclicAMP. Inhibition was also evident at the mRNA level. On the other hand CPZ (10-25 microM) also inhibited TNF-alpha activity: in fact it reduced the cytotoxicity of TNF-alpha on L929 cells (EC50 was increased four times) and could provide protection even as a post-treatment. CPZ inhibited TNF-induced apoptosis in L929 cells, as detected by analysis of nuclear morphology. However, since we showed that apoptosis was very limited, and was not the main mode of cell death in our conditions, this could not explain the overall protection. Since CPZ did not interfere with either the oligomerization state of TNF-alpha or its receptor binding, our data suggest that it reduced cytotoxicity by inhibiting some steps in the TNF-alpha signalling pathways

Protective effect of ciliary neurotrophic factor (CNTF) in a model of endotoxic shock: action mechanisms and role of CNTF receptor alpha

: Ciliary neurotrophic factor (CNTF) inhibits the production of tumor necrosis factor (TNF) in lipopolysaccharide (LPS)-treated mice and protects against LPS lethality when coadministered with its soluble receptor (sCNTFR alpha). Both of these activities are abolished in adrenalectomized (ADX) mice. LPS-induced pulmonary polymorphonuclear neutrophil (PMN) infiltration and nitric oxide (NO) production were also inhibited by CNTF + sCNTFR alpha but not by CNTF alone. sCNTFR alpha did not alter the clearance or tissue distribution of CNTF. Furthermore, CNTF variants coadministered with sCNTFR alpha protected against LPS toxicity in a manner related to their affinity for the beta components of CNTFR. Thus, inhibition of TNF production and protection against LPS lethality by CNTF/sCNTFR alpha require an intact hypothalamus-pituitary-adrenal axis (HPAA) and may be mediated by endogenous glucocorticoids. This protective effect is, at least in part, due to the inhibition of PMN infiltration and NO production, and appears to be mediated by cells displaying only beta-receptor subtypes