Preliminary results of a randomized controlled trial carried out with a fixed combination of S-adenosyl-L-methionine and betaine versus amitriptyline in patients with mild depression

Depression-associated gut microbes, metabolites and clinical trials

Depression is one of the most prevalent mental disorders today. Over the past decade, there has been considerable attention given to the field of gut microbiota associated with depression. A substantial body of research indicates a bidirectional communication pathway between gut microbiota and the brain. In this review, we extensively detail the correlation between gut microbiota, including Lactobacillus acidophilus and Bifidobacterium longum, and metabolites such as short-chain fatty acids (SCFAs) and 5-hydroxytryptamine (5-HT) concerning depression. Furthermore, we delve into the potential health benefits of microbiome-targeted therapies, encompassing probiotics, prebiotics, and synbiotics, in alleviating depression. Lastly, we underscore the importance of employing a constraint-based modeling framework in the era of systems medicine to contextualize metabolomic measurements and integrate multi-omics data. This approach can offer valuable insights into the complex metabolic host-microbiota interactions, enabling personalized recommendations for potential biomarkers, novel drugs, and treatments for depression.

Discovery of the Potential Novel Pharmacodynamic Substances From Zhi-Zi-Hou-Po Decoction Based on the Concept of Co-Decoction Reaction and Analysis Strategy

Background: Zhi-Zi-Hou-Po Decoction (ZZHPD), a classic traditional Chinese medicine (TCM) formula, is clinically used to treat insomnia and depression. The analysis strategy based on the concept of co-decoction of TCM is helpful to analyse the effective substances of TCM formula in depth. Aim of the study: This manuscript intends to take ZZHPD as a model sample to explore the phenomenon of co-decoction of complex formula in the combination of liquid chromatography-mass spectrometry (LC-MS) technology, data analysis, and molecular docking. Materials and methods: In the current research, an innovative LC-MS method has been established to study the active ingredients in ZZHPD, and to identify the ingredients absorbed into the blood and brain tissues of mice. And molecular docking was used to study the binding pattern and affinities of known compounds of the brain tissue toward insomnia related proteins. Results: Based on new processing methods and analysis strategies, 106 chemical components were identified in ZZHPD, including 28 blood components and 18 brain components. Then, by comparing the different compounds in the co-decoction and single decoction, it was surprisingly found that 125 new ingredients were produced during the co-decoction, 2 of which were absorbed into the blood and 1 of which was absorbed into brain tissue. Ultimately, molecular docking studies showed that 18 brain components of ZZHPD had favourable binding conformation and affinity with GABA, serotonin and melatonin receptors. The docking results of GABRA1 with naringenin and hesperidin, HCRTR1 with naringenin-7-O-glucoside, poncirenin and genipin 1-gentiobioside, and luteolin with SLC6A4, GLO1, MAOB and MTNR1A may clarify the mechanism of action of ZZHPD in treating insomnia and depression. Conclusion: Our study may provide new ideas for further exploring the effective substances in ZZHPD.

Evidence to Support the Use of S-Adenosylmethionine for Treatment of Post-Concussive Sequelae in the Military

INTRODUCTION

Since the year 2000, over 413,000 service members have sustained traumatic brain injury (TBI) and may present with post-concussive sequelae including headaches, fatigue, irritability, cognitive problems, depression, insomnia, and chronic pain. Although the focus of the article is on military TBI, the usefulness of S-adenosylmethionine (SAMe) would extend to both civilian and military populations. This narrative review examines the preclinical and clinical literature of SAMe's metabolism and alterations seen in disease states such as depressive disorders, pain disorders, fatigue, cognition, dementia, use in pregnancy and peripartum, children, adolescents, and adults, to the elderly with and without dementia, stroke, and neurodegeneration, in order to highlight its potential benefit in post-concussive sequelae after TBI.

MATERIALS AND METHODS

A MEDLINE/PubMed and Cochrane Database search was conducted between May 3, 2018 and July 30, 2019 by combining search terms for SAMe with terms for relevant disease states including depression, brain injury, dementia, Alzheimer's disease, Parkinson's disease, cognition, fatigue, and pain. This search retrieved a total of 676 references. 439 were excluded for being over a 10-year publication date, except where clinically relevant. After additional removal of repeated articles, the number of articles were totaled 197. An additional 59 articles were excluded: 10 not in English, 4 duplicates, 4 not original investigations, and 41 outside the scope of this article. The remaining 138 articles were used in this review and included 25 clinical studies, 46 preclinical studies, 63 reviews, and 4 case reports.

RESULTS

This narrative review examined the preclinical and clinical literature of SAMe's metabolism and alterations seen in MDD, pain disorders, fatigue, cognition and memory, dementia, and other disorders to highlight the potential benefit of SAMe in post-concussive sequelae in mTBI. The literature showed potential for improvement, safety, and tolerability in these symptom clusters commonly seen in military mild TBI (mTBI).

CONCLUSION

There is evidence of a potential benefit of SAMe as an intervention to help with symptoms across the range of post-concussive sequelae and syndromes commonly seen in military mTBI. Since the discovery of SAMe in 1952, this pleiotropic molecule has shown the significance of its involvement in several metabolic cascades in such disparate systems as epigenetics, bioenergetics, DNA methylation, neurotransmitter systems, and potential usefulness in military TBI. Significant limitations include disparate presentations seen in patients with mild TBI, those with post-concussive syndrome, as well as those with comorbid depression and posttraumatic stress disorder. Also, over-the-counter medications are not regulated and SAMe products may vary widely in price and quality. Given the potential for mania in patients with bipolar disorder, evaluation and recommendations should be made by a physician able to evaluate the underlying bipolar diathesis. Furthermore, this narrative review serves as the rationale for future open-label and double-blind placebo-controlled trials in military mTBI and SAMe.

Gut microbial metabolites in depression: understanding the biochemical mechanisms

Gastrointestinal and central function are intrinsically connected by the gut microbiota, an ecosystem that has co-evolved with the host to expand its biotransformational capabilities and interact with host physiological processes by means of its metabolic products. Abnormalities in this microbiota-gut-brain axis have emerged as a key component in the pathophysiology of depression, leading to more research attempting to understand the neuroactive potential of the products of gut microbial metabolism. This review explores the potential for the gut microbiota to contribute to depression and focuses on the role that microbially-derived molecules – neurotransmitters, short-chain fatty acids, indoles, bile acids, choline metabolites, lactate and vitamins – play in the context of emotional behavior. The future of gut-brain axis research lies is moving away from association, towards the mechanisms underlying the relationship between the gut bacteria and depressive behavior. We propose that direct and indirect mechanisms exist through which gut microbial metabolites affect depressive behavior: these include (i) direct stimulation of central receptors, (ii) peripheral stimulation of neural, endocrine, and immune mediators, and (iii) epigenetic regulation of histone acetylation and DNA methylation. Elucidating these mechanisms is essential to expand our understanding of the etiology of depression, and to develop new strategies to harness the beneficial psychotropic effects of these molecules. Overall, the review highlights the potential for dietary interventions to represent such novel therapeutic strategies for major depressive disorder.

Maternal choline status during pregnancy, but not that of betaine, is related to antenatal mental well-being: The growing up in Singapore toward healthy outcomes cohort

BACKGROUND

Choline and betaine status have previously been associated with symptoms of depression. However, the relation of maternal plasma choline and betaine concentrations in pregnancy to peripartum maternal mood is unknown.

METHODS

Maternal plasma choline and betaine concentrations (μmol/L) were measured at 26-28 weeks gestation in the Growing Up in Singapore Toward healthy Outcomes (GUSTO) mother-offspring cohort. Participants completed the State-Trait Anxiety Inventory (STAI) and Edinburgh Postnatal Depression Scale (EDPS) at 26-28 weeks gestation (n = 949) and at 3 months postnatal (n = 689): higher scores are indicative of more symptoms of anxiety and depression. Multivariate linear regression models were used to estimate the association of choline and betaine with ante- and postnatal mental well-being adjusting for covariates.

RESULTS

Mean (SD) antenatal plasma choline and betaine concentrations were 9.2 μmol/L (1.6) and 13.1 μmol/L (2.7), respectively. Plasma choline concentrations were positively associated with antenatal depressive (β = .24 EPDS score [95% CI: 0.05-0.43] per μmol/L] and anxiety symptoms (β = .46 STAI-state score [95% CI: 0.03-0.88] per μmol/L) adjusting for covariates. Plasma betaine concentrations were not associated with antenatal depression or anxiety symptoms. No associations were observed between pregnancy choline or betaine and postnatal mental well-being.

CONCLUSION

This study suggests that higher maternal plasma choline status during pregnancy is associated with more symptoms of antenatal depression and anxiety, whereas plasma betaine concentrations showed no associations. No associations were observed for postnatal mental well-being. Prospective studies are required to replicate these findings and further examine the direction of causality and possible biological mechanisms.

S-adenosyl methionine (SAMe) for depression in adults

BACKGROUND

Depression is a recurrent illness with high rates of chronicity, treatment-resistance and significant economic impact. There is evidence in the literature that S-adenosyl methionine (SAMe), a naturally occurring compound in the human body, has antidepressant efficacy. This product may be an important addition to the armamentarium of antidepressant agents.

OBJECTIVES

To assess the effects of SAMe in comparison with placebo or antidepressants for the treatment of depression in adults.

SEARCH METHODS

We searched the Cochrane Common Mental Disorders Group's Specialised Register (CCMDCTR Studies and Reference Register), MEDLINE, EMBASE, PsycINFO, international trial registers ClinicalTrials.gov and the World Health Organization trials portal (ICTRP). We checked reference lists, performed handsearching and contacted experts in the field. The CCMDCTR literature search was last updated on 5 February 2016.

SELECTION CRITERIA

Randomised controlled trials comparing SAMe with placebo or antidepressants in adults with a diagnosis of major depression.

DATA COLLECTION AND ANALYSIS

Two authors independently performed extraction of data and assessment of risk of bias. We contacted trialists of included studies for additional information.

MAIN RESULTS

This systematic review included eight trials comparing SAMe with either placebo, imipramine, desipramine or escitalopram. We accepted trials that used SAMe as monotherapy or as add-on therapy to selective serotonin reuptake inhibitors (SSRIs), and we accepted both oral and parenteral administration. The review involved 934 adults, of both sexes, from inpatient and outpatient settings.The trials were at low risk of reporting bias. We judged the risk of selection, performance, detection and attrition bias as unclear or low, and one study was at high risk of attrition bias.There was no strong evidence of a difference in terms of change in depressive symptoms from baseline to end of treatment between SAMe and placebo as monotherapy (standardised mean difference (SMD) -0.54, 95% confidence interval (CI) -1.54 to 0.46; P = 0.29; 142 participants; 2 studies; very low quality evidence). There was also no strong evidence of a difference in terms of drop-out rates due to any reason between SAMe and placebo, when used as monotherapy (risk ratio (RR) 0.88, 95% CI 0.61 to 1.29; P = 0.52; 142 participants; 2 studies; low quality evidence).Low quality evidence showed that the change in depressive symptoms from baseline to end of treatment was similar between SAMe and imipramine, both as monotherapy (SMD -0.04, 95% CI -0.34 to 0.27; P = 0.82; 619 participants; 4 studies). There was also no strong evidence of a difference between SAMe and a tricyclic antidepressant in terms of drop-outs due to any reason (RR 0.61, 95% CI 0.28 to 1.31; P = 0.2; 78 participants; 3 studies; very low quality evidence).There was little evidence of a difference in terms of change in depressive symptoms from baseline to end of treatment between SAMe and escitalopram, both as monotherapy (MD 0.12, 95% CI -2.75 to 2.99; P = 0.93; 129 participants; 1 study; low quality evidence). There was no strong evidence of a difference between SAMe and escitalopram in terms of drop-outs due to any reason (RR 0.81, 95% CI 0.57 to 1.16; P = 0.26; 129 participants; 1 study; low quality evidence).There was low quality evidence that SAMe is superior to placebo as add-on to SSRIs in terms of change in depressive symptoms from baseline to end of treatment (MD -3.90, 95% CI -6.93 to -0.87; P = 0.01; 73 participants; 1 study). There was no strong evidence of a difference between SAMe and placebo as adjunctive therapy to an SSRI in terms of drop-outs due to any reason (RR 0.70, 95% CI 0.31 to 1.56; P = 0.38; 73 participants; 1 study; very low quality evidence).For all comparisons, secondary outcome measures of response and remission rates were consistent with these primary outcome measures.With regard to all extractable measures of the acceptability of SAMe, the quality of the evidence was low to very low. SAMe was not different from placebo and established antidepressants. The exception was that compared to imipramine, fewer participants experienced troublesome adverse effects when treated with parenteral SAMe.The specific adverse effects were not detailed in most of the included studies. There were two reports of mania/hypomania recorded for 441 participants in the SAMe arm.

AUTHORS' CONCLUSIONS

Given the absence of high quality evidence and the inability to draw firm conclusions based on that evidence, the use of SAMe for the treatment of depression in adults should be investigated further. Future trials should be in the form of large randomised controlled clinical trials of high methodological quality, with particular attention given to randomisation, allocation concealment, blinding and the handling of missing data. Comparator antidepressants from all classes should be used. Adverse events should be detailed for each participant, bearing in mind that induction of mania is of particular interest.