There is some evidence that major depression-in particular, treatment-resistant depression (TRD)-is accompanied by activation of the inflammatory response system and that proinflammatory cytokines may play a role in the etiology of depression. This study was carried out to examine the effects of antidepressive agents, i.e., imipramine, venlafaxine, L-5-hydroxytryptophan, and fluoxetine on the production of interferon-γ (IFN-γ), a proinflammatory cytokine, and interleukin-10 (IL-10), a negative immunoregulatory cytokine. Diluted whole blood of fluoxetine-treated patients with TRD (mean age, 50.6 ± 3.9 years) and age-matched healthy controls (mean age, 51.6 ± 1.7 years) and younger healthy volunteers (mean age, 35.4 ± 9.6 years) was stimulated with phytohemagglutinin (1 μg/mL) and lipopolysaccharide (5 μg/mL) for 48 hours with and without incubation with the antidepressants at 10−6 M and 10−5 M. IFN-γ and IL-10 were quantified by means of enzyme-linked immunoassays. The ratio of IFN-γ to IL-10 production by immunocytes was computed because this ratio is of critical importance in determining the capacity of immunocytes to activate or inhibit monocytic and T-lymphocytic functions. All four antidepressive drugs significantly increased the production of IL-10. Fluoxetine significantly decreased the production of IFN-γ. All four antidepressants significantly reduced the IFN-γ/IL-10 ratio. There were no significant differences in the antidepressant-induced changes in IFN-γ or IL-10 between younger and older healthy volunteers and TRD patients. Tricyclic antidepressants, selective serotonin reuptake inhibitors, and serotonin-noradrenaline reuptake inhibitors, as well as the immediate precursor of serotonin, have a common, negative immunoregulatory effect by suppressing the IFN-γ/IL-10 production ratio. It is suggested that the therapeutic efficacy of antidepressants may be related to their negative immunoregulatory effects.
Use of methamphetamine (MA) commonly co-occurs with the use of other substances. The present study aims to examine substance initiation patterns of other substances, including alcohol, nicotine, inhalants, and cannabis (OTH), in MA users and its consequence on the time lag of MA dependence.Sociodemographic, environmental, and clinical data were obtained from MA users at a Thai substance treatment center. The Semi-Structured Assessment for Drug Dependence and Alcoholism was employed to diagnose drug dependence.Of 991 MA users, 52.6% were males, and the average age was 26.8 ± 7.1 years. The mean age of first MA use (18 years) was greater than the mean age of first use of alcohol (17 years), nicotine (16 years), and inhalants (15 years) (P < 0.001), but was comparable with the mean age at the first use of cannabis (P > 0.05). Family history of MA use and nicotine dependence were associated with early MA onset. Participants who used MA as their first drug (MA>OTH) were more likely to be female and less likely to smoke intensely and to be exposed to severe traumatic events than those who used MA later than other substances (OTH>MA). The time lag from age at onset of MA use to MA dependence was shorter in OTH>MA than in MA>OTH (3 vs 5 years; χ = 5.7, P = 0.02, log-rank test).A higher proportion of women was observed in MA>OTH than in OTH>MA. The use of other substances before MA increases the individual's vulnerability in shortening the interval between age at onset of MA use and MA dependence in a substance treatment cohort.
An abstract is not available for this content. As you have access to this content, full HTML content is provided on this page. A PDF of this content is also available in through the ‘Save PDF’ action button.
The aim of this study was to determine if variable number of tandem repeats (VNTR) in the second intron (STin2) of the serotonin transporter (SLC6A4) gene was associated with tobacco use disorder, successful smoking cessation, or smoking characteristics. In this case–control study, patients with current tobacco use disorder, diagnosed according to DSM IV criteria (n = 185), and never-smokers, diagnosed according to CDC criteria (n = 175), were recruited and received 52 weeks of combined pharmacotherapy and cognitive therapy. Successful smoking cessation was defined as exhaled carbon monoxide < 6 ppm. SLC6A4 gene STin2 VNTR polymorphism was assessed using a Multiplex-PCR-based method. At baseline, participants were evaluated using the Fagerström Test for Nicotine Dependence (FTND) and the ASSIST scale. The STin2.12 allele (OR = 2.45; 95% CI = 1.44-4.15, p < 0.001) was associated with an increased risk for tobacco use disorder, while the STin2.10/10 genotype (OR = 0.42; 95% CI 0.25-0.71, p < 0.001) decreased risk. There were no significant associations between tobacco use disorder and the STin2.10 or STin2.9 alleles or the other genotypes (STin2.12/12, 12/10, 12/9, 10/9 or 9/9). There were no significant associations between the STin2 genotypes and alleles and successful smoking cessation, smoking characteristics and increased alcohol or sedative use risk. Our results suggest that the STin2.10/10 genotype and STin2.12 allele are associated with tobacco use disorder or nicotine dependence, but not with treatment response or severity of dependence. It is hypothesized that the ST2in.12 allele by modulating the metabolism of serotonin may participate in the pathophysiology of tobacco use disorder or nicotine dependence.
Alzheimer's disease (AD), the most common form of dementia, is a progressive disorder manifested by gradual memory loss and subsequent impairment in mental and behavioral functions. Though the primary risk factor for AD is advancing age, other factors such as diabetes mellitus, hyperlipidemia, obesity, vascular factors and depression play a role in its pathogenesis. The human gastrointestinal tract has a diverse commensal microbial population, which has bidirectional interactions with the human host that are symbiotic in health, and in addition to nutrition, digestion, plays major roles in inflammation and immunity. The most prevalent hypothesis for AD is the amyloid hypothesis, which states that changes in the proteolytic processing of the amyloid precursor protein leads to the accumulation of the amyloid beta (Aβ) peptide. Aβ then triggers an immune response that drives neuroinflammation and neurodegeneration in AD. The specific role of gut microbiota in modulating neuro-immune functions well beyond the gastrointestinal tract may constitute an important influence on the process of neurodegeneration. We first review the main mechanisms involved in AD physiopathology. Then, we review the alterations in gut microbiota and gut-brain axis that might be relevant to mediate or otherwise affect AD pathogenesis, especially those associated with aging. We finally summarize possible mechanisms that could mediate the involvement of gut-brain axis in AD physiopathology, and propose an integrative model.
In the past, some researchers found increased cortisol and prolactin responses to the administration of fenfluramine in major-depressed patients. It was believed that the fenfluramine test could prove to constitute another challenge probe to reflect the central serotonergic function. The present study was conducted in order to investigate the pituitary/adrenal responses to fenfluramine in major- versus minor-depressed patients. To this end we administered 60 mg D,L-fenfluramine p.o. to 40 depressed patients categorized according to the DSM-III. The basal levels of cortisol, adrenocorticotrophic hormone (ACTH), beta-endorphins and prolactin and their levels 2 and 4 h after fenfluramine administration were measured. We found no significant effect for fenfluramine treatment on cortisol, ACTH or beta-endorphins. There was a significant (p = 0.02) effect for fenfluramine treatment on prolactin. The enhanced secretion of prolactin was only significant (p = 0.006) in major (296.X2, 296.X3, 296.X4) and not in minor (300.40, 309.00) depressives. It was concluded that our findings corroborate the thesis of a hypersensitive serotonergic neurotransmission during a major depressive episode.
Both corticotropin releasing hormone (CRH) and serotonin (5-HT) participate in the stress response and are known to modulate cytokine release by human immune cells. Extracellular 5-HT concentrations at or above the serum values have negative immunoregulatory effects by inhibiting the production of interferon-γ (IFNγ), a pro-inflammatory cytokine produced by Th-1-like lymphocytes, whereas 5-HT has no significant effects on the production of interleukin-10 (IL10), an anti-inflammatory cytokine. In one study, CRH significantly decreases IFNγ production by cultured human peripheral blood immunocytes, whereas in other studies CRH increases the production of cytokines, such as IL-1, IL-2 and IL-6. The aims of the present study were to examine i) the effects of CRH, 10–9 M, 10–8 M and 10–7 M, on the stimulated production of IFNγ, IL-10 and tumor necrosis factor-α (TNFα) by human whole blood; and ii) whether CRH, 10–9 M, 10–8 M and 10–7 M, may antagonize some of the negative immunoregulatory effects of 5-HT, 1.5 µg/mL or 15 µg/mL. We found that CRH, 10–9 M, 10–8 M and 10–7 M, had no significant effects either on the stimulated production of IFNγ, IL-10 or TNFα or on the IFNγ/IL-10 production ratio, which reflects the pro-inflammatory capacity of the culture. 5-HT, 1,5 µg/dL and 15 µg/dL, significantly suppressed the production of IFN γ and TNFα and the IFNγ/IL-10 production ratio. CRH, 10–7 M, significantly reversed the 5-HT (1.5 µg/mL and 15 µg/mL)-induced suppression of IFNγ production. CRH at all concentrations significantly blocked the 5-HT (1.5 µg/mL and 15 µg/ mL)-induced suppression of TNFα production. The results suggest that CRH has no significant direct effects on the production of IFN γ, IL-10 and TNFα, but antagonizes the negative immunoregulatory effects of 5-HT on the production of IFNγ and TNFα and on the IFNγ/IL-10 production ratio.
There are different case definitions of premenstrual syndrome, one proposed by the American College of Obstetricians and Gynecologists (ACOG) and another based on the Daily Record of Severity of Problems (DRSP) scores. Here we review our recent findings indicating that the gold-standard methods to assess PMS, including ACOG, provide a high degree of false-negative findings. We propose a new case definition of the Menstrual Cycle-Associated Syndrome (MCAS), which is characterized by increased DRSP scores during the menstrual cycle and symptom that increases the week prior to the menses. The MCAS case definition was externally validated by diverse biomarkers including plasma levels of progesterone and estradiol, chemokines (e.g. CCL2, CCL5 and CCL11), epidermal growth factor, hydroperoxides, paraoxonase 1 activity and complement C4. These biomarkers as well as IgA responses to Gram-negative bacteria are significantly associated with the DRSP and its subdomains including depression, anxiety, and physiosomatic symptoms(fatigue, pain). In conclusion, we propose, a) to use the MCAS diagnosis as an indicant of menstrual cycle-related symptoms; and b) to examine the associations of the time series in the DRSP and its subdomains and those in biomarkers including distributed lag models. Aberrations in the uterine-chemokine-brain-axis underpin the pathophysiology of MCAS whereby suboptimal pre-ovulatory follicular development coupled with a relative corpus luteum insufficiency may drive increased chemokine production, lowered antioxidant defenses, neuro-oxidative stress pathways, and increased bacterial translocation. As such, we have delineated new drug targets for the treatment of MCAS. This opinion paper reviews new possible treatments that should be trialed in MCAS.
No studies have examined the immune fingerprint of major neuro-cognitive psychosis (MNP) or deficit schizophrenia using M1 macrophage cytokines in combination with chemokines such as CCL-2 and CCL-11. The present study delineated the neuro-immune fingerprint of MNP/deficit schizophrenia by analyzing plasma levels of IL-1&beta;, sIL-1RA, TNF-&alpha;, sTNFR1, sTNFR2, CCL-2 and CCL-11 in MNP (n=120) versus healthy controls (n=54) in association with neurocognitive deficits (as assessed with the Brief Assessment of Cognition in Schizophrenia) and PHEMN (psychotic, hostility, excitation, mannerism and negative) symptoms. All immune biomarkers were significantly higher in MNP than in normal controls. MNP was best predicted by a combination of CCL-11, TNF-&alpha;, IL-1&beta; and sIL-1RA which yielded a bootstrapped (n=2000) area under the Receiver Operating Curve of 0.985. Composite scores reflecting M1 macrophage activity and neurotoxic potential including combined effects of CCL-11 plus CCL-2 were significantly increased in MNP. Nevertheless, the effects of increased IL-1&beta; and TNF-&alpha; in MNP were attenuated (statistically) by increased sIL-1RA and sTNFR2, two negative immune-regulatory markers. A large part of the variance in PHEM (38.4%-52.6%) and negative (65.8-7439%) symptoms was explained by combinations of immune markers whereby CCL-11 was consistently the most important. The immune markers also explained a large part of the variance in the Mini Mental State examination, list learning, digit sequencing task, category instances, controlled word association, symbol coding and Tower of London. Soft Independent Modeling of Class Analogy performed on the biomarkers showed that the inter-class distance between the models constructed around MNP and controls was 19.3 indicating a good separation. Partial Least Squares analysis showed that 72.7% of the variance in overall phenomenology was explained by the regression on IL-1&beta;, sIL-1RA, CCL-11, TNF-&alpha; (all positively) and education (inversely). It is concluded that the combination of the above-mentioned markers defines MNP as a distinct neuro-immune disorder and that those markers in combination explain a large part of the variance in memory and executivive impairments and PHEMN symptoms.
There is evidence that inflammatory, oxidative and nitrosative stress (IO&NS) pathways participate in the pathophysiology of a subgroup of patients with Myalgic Encephalomyelitis/chronic fatigue syndrome (ME/CFS). Increased IgM-related autoimmune responses to oxidative specific epitopes (OSEs), including malondialdehyde (MDA), oleic acid and phosphatidyl inositol (Pi), and nitroso-(NO)-adducts, including NO-tryptophan (NOW), NO-arginine and NO-cysteinyl, are frequently observed in ME/CFS. Autoimmune responses in ME/CFS may be driven by increased bacterial translocation as measured by IgM and IgA responses to LPS of gram negative bacteria.The aim of this study is to examine whether IgM responses to OSEs and NO-adducts are related to a better outcome as measured by the Fibromyalgia and Fatigue Rating Scale (FF). 76 ME/CFS patients with initially abnormal autoimmune responses were treated with care-as-usual, including nutraceuticals with anti-IO&NS effects (NAIOS), such as L-carnitine, coenzyme Q10, taurine + lipoic acid, with or without curcumine + quercitine or N-acetyl-cysteine, zinc + glutamine.We found that use of these NAIOS was associated with highly significant reductions in initially increased IgM-mediated autoimmune responses to OSEs and NO-adducts. A greater reduction in autoimmune responses to OSEs during intake of these NAIOS was associated with a lower FF score. Reductions in IgM responses to oleic acid, MDA and Pi, but not in any of the NO-adducts, were associated with reductions in severity of illness. These associations remained significant after adjusting for possible effects of increased bacterial translocation (leaky gut).Our results show that autoimmune responses to OSEs are involved in the pathophysiology of ME/CFS and that these pathways are a new drug target in a subgroup of ME/CFS patients. Although hypernitrosylation and nitrosative stress play a role in ME/CFS, reductions in these pathways are not associated with lowered severity of illness. Randomized controlled trials with NAIOS should be carried out in the subgroup of ME/CFS patients with initially increased autoimmune responses to OSEs.
