The gut reaction to couples' relationship troubles: A route to gut dysbiosis through changes in depressive symptoms

Depressive symptoms at short-, medium-, and long-term follow-up after bariatric surgical procedures: A systematic review and meta-analysis

IMPORTANCE

Patients experience both positive and negative changes in mood following bariatric surgery and mental health outcomes have been reported to differ between procedure types. Understanding changes in symptoms over time and between surgical procedures is vital to providing meaningful, long-term, patient-centered care.

OBJECTIVE

To examine the nature and time course of changes in depressive symptoms after different bariatric procedures.

EVIDENCE REVIEW

Medline, Embase, Emcare, PsycINFO, CINAHL, and CENTRAL databases were systematically searched from inception to January 18, 2024. Ninety publications describing patient-reported depressive symptoms in 13,146 individuals undergoing bariatric procedures were included.

FINDINGS

Qualitative analysis indicated a reduction of depressive symptoms at all time points following all bariatric procedure types. However, a subset of patients experienced worsening symptoms post-surgery. Meta-analyses indicated depressive symptoms improve following bariatric surgery by an SMD of -0.6 (95% CI: -0.8, -0.4) in the short term (0-4 months post-surgery), -0.9 (95% CI: -1.0, -0.8) in the medium term (5-12 months), and -0.7 (95% CI: -0.9, -0.5) in the long term (> 12 months). There was no evidence that surgery type was associated with the change in depressive symptoms at any time point post-surgery.

CONCLUSIONS AND RELEVANCE

Patient-reported depressive symptoms improve following bariatric surgery with improvements peaking in the medium term and diminishing over time. Significant heterogeneity in the results cannot be explained by surgery type, baseline depression, or depression instrument used across studies. Long-term management of post-bariatric surgery patients must consider the potential for adverse psychological effects of surgery.

Critical Review of the Cross-Links Between Dietary Components, the Gut Microbiome, and Depression

The complex relationship between diet, the gut microbiota, and mental health, particularly depression, has become a focal point of contemporary research. This critical review examines how specific dietary components, such as fiber, proteins, fats, vitamins, minerals, and bioactive compounds, shape the gut microbiome and influence microbial metabolism in order to regulate depressive outcomes. These dietary-induced changes in the gut microbiota can modulate the production of microbial metabolites, which play vital roles in gut-brain communication. The gut-brain axis facilitates this communication through neural, immune, and endocrine pathways. Alterations in microbial metabolites can influence central nervous system (CNS) functions by impacting neuroplasticity, inflammatory responses, and neurotransmitter levels-all of which are linked to the onset and course of depression. This review highlights recent findings linking dietary components with beneficial changes in gut microbiota composition and reduced depressive symptoms. We also explore the challenges of individual variability in responses to dietary interventions and the long-term sustainability of these strategies. The review underscores the necessity for further longitudinal and mechanistic studies to elucidate the precise mechanisms through which diet and gut microbiota interactions can be leveraged to mitigate depression, paving the way for personalized nutritional therapies.

Couples in breast cancer survivorship: Daily associations in relationship satisfaction, stress, and health

Romantic relationships are a key health determinant underlying both morbidity and mortality. Dr. Janice Kiecolt-Glaser's prolific research revealed cardiovascular, metabolic, endocrine, and immune pathways connecting marriage to health and longevity. In addition to her empirical work, she developed conceptual models on marriage, the gut microbiome, stress reactivity, and spousal health concordance; these models guide and inspire mechanistic research, serve as essential readings for graduate students and mentees, and provide inspiration for researchers across career stages. This paper highlights Dr. Kiecolt-Glaser's influential work, includes personal reflections and professional growth as past mentees, and provides Dr. Kiecolt-Glaser-inspired evidence linking relationships to health among couples in breast cancer survivorship. Using baseline questionnaires and daily dairies, breast cancer survivors (stage I-IIIB) and their cohabiting partners (60 individuals, 30 couples) rated their relationship satisfaction, stress, and physical health symptoms every day for 7 days. Results suggest that breast cancer survivors and their partners who felt more satisfied with their relationships also felt less stressed, both typically and on a daily basis. Survivors' and partners' lower stress was also associated with fewer physical health problems on average and in daily life. These findings demonstrate the daily stress and health advantages of satisfying relationships for both breast cancer survivors and their partners. We discuss the study's implications and several avenues for Dr. Kiecolt-Glaser-inspired research addressing a relationship's long-term health impact among couples in survivorship.

The post-Cartesian dilemma: Reuniting the mind and body through psychoneuroimmunology

While today, it might seem absurd to hear anyone claim that stress does not alter all aspects of the human experience, including behavioral, cognitive, affective, and physiological processes. Dr. Janice Kiecolt-Glaser started her career at a time when stress was primarily considered a neuroendocrine response with cardiovascular repercussions. She was part of a small group of innovative scientists who began to push the boundaries of stress research - many contemporary immunologists and virologist disputed their early results in 1980s and 90s - and, yet, they persevered by connecting psychological stress to altered immune function via stress-related neuroendocrine changes. As a clinical psychologist, she focused mainly on human research studies to advance the field of psychoneuroimmunology throughout her career. Her research demonstrates how adversity and psychosocial aspects of human experience alter physiological functioning, primarily immune, and health or, in other words, the embodiment of our lived experiences. This short review is a contextualized synthesis of Dr. Kiecolt-Glaser's key contributions to the fields of psychoneuroimmunology and health psychology and her influence on my present day thinking and research approaches, as well as potential steps forward in our post-pandemic world.

A social science: Using psychoneuroimmunology principles to promote career longevity, productivity, and meaning

Over the past several decades, psychoneuroimmunologists have uncovered key principles (e.g., social support and stress management) that can inform future research content and conduct. That is, psychoneuroimmunology (PNI) can inform how scientists from all disciplines engage in the scientific method in a more sustainable manner. Dr. Janice Kiecolt-Glaser, a PNI pioneer, recently ended her long and celebrated career. Her unique engagement in the scientific method, including her mentorship style, is worthy of closer examination. As her final graduate student, I observed Dr. Kiecolt-Glaser's science and mentorship style at their full maturity. Her scientific content, remarkable in its own right, is the subject of commentaries and accolades; yet, her scientific conduct - the foundation of her success and innovation - deserves further consideration. This article outlines ten research conduct principles that Dr. Kiecolt-Glaser explicitly and implicitly taught: (1) applying the literature to one's own health behaviors; (2) knowing and remembering "the why" behind the science; (3) developing and adhering to a vision; (4) creating a streamlined workflow; (5) embracing team science; (6) pursuing depth and breadth; (7) communicating ideas clearly; (8) engaging in a daily rhythm of science; (9) treating trainees like future primary investigators; and (10) working toward clinical meaningfulness. These principles correspond to PNI findings and account for her health and longevity as a scientist.

Moving toward affective immunology: Legacy and future directions

The term "affective immunology" has recently been used to denote a field focused on the interplay between affective processes (including mood states, specific emotions, and regulatory processes) and various aspects of immune function. The overarching goals of this commentary are a) to provide historical underpinnings of this field with a focus on the profound impact of the work of Janice Kiecolt-Glaser, who is further honored in this special issue, b) to review important off-shoots of her legacy work in this domain, and c) to highlight important future directions for the field. Kiecolt-Glaser's work laid much of the foundation for affective immunology, with groundbreaking research related to depression, hostility and dyadic interactions, loneliness, and other affective patterns, often in the context of holistic models, novel experimental designs, and interventions. Her former mentees (and many of their mentees) have carried on her legacy in these domains, in ways that continue to advance appreciation of how affective processes relate to immune function. There are numerous remaining questions for the field to pursue, including better understanding of the role of emotion regulation, emotional reactivity and recovery, restorative processes, affective variability, and developmental and dynamic social processes. Such work will require greater use of longitudinal and within-person approaches and/or examination of processes in daily life, as well as models that account for interactive and reciprocal processes and which integrate behavior, social context, sociocultural factors, individual differences, and other aspects of health. As more work in these domains continues, building on Kiecolt-Glaser's rich legacy, we move toward the emergence of affective immunology as an important subfield in the domain of psychoneuroimmunology, one which will offer more nuanced understanding of the role of affective processes in immune health.

Couples-based health behavior change interventions: A relationship science perspective on the unique opportunities and challenges to improve dyadic health

Epidemiological studies indicate that better marital quality is associated with less morbidity and premature mortality. A number of interpersonal processes related to marital quality are also associated with health-relevant surrogate biomarkers across different physiological systems. Despite these replicated correlational findings, few interventions have harnessed interpersonal processes as potential interventions to enhance health. Building on Dr. Janice Kiecolt-Glaser's model of relationships and health, we propose that couples-based health behavior change interventions may represent an effective way to decrease dysregulation across autonomic, endocrine and immune systems and, ultimately, improve dyadic health. Given that the cohabiting partner is an essential part of the social context in which the behavior change is being pursued, it is important to consider the relational issues triggered by dyadic interventions. Using a relationship science perspective, this article reviews the literature on couples' concordance in health behaviors and health outcomes, the potential pathways underlying this concordance, theories of the couple as a self-sustaining social system, dyadic adaptation of individual self-regulation strategies, effective and ineffective social support and social control in couple relationships, the integration of relationship-building and health behavior change strategies, and the consideration of key moderators related to the nature of the relationship and the context surrounding the relationship. These findings highlight the importance of adopting a relationship science perspective when designing and testing dyadic interventions to improve health outcomes. The data reviewed provide insights on how to optimize couples-based health behavior change interventions to reduce physiological dysregulation and improve dyadic health.

Human Gut Microbiota for Diagnosis and Treatment of Depression

Nowadays, depressive disorder is spreading rapidly all over the world. Therefore, attention to the studies of the pathogenesis of the disease in order to find novel ways of early diagnosis and treatment is increasing among the scientific and medical communities. Special attention is drawn to a biomarker and therapeutic strategy through the microbiota-gut-brain axis. It is known that the symbiotic interactions between the gut microbes and the host can affect mental health. The review analyzes the mechanisms and ways of action of the gut microbiota on the pathophysiology of depression. The possibility of using knowledge about the taxonomic composition and metabolic profile of the microbiota of patients with depression to select gene compositions (metagenomic signature) as biomarkers of the disease is evaluated. The use of in silico technologies (machine learning) for the diagnosis of depression based on the biomarkers of the gut microbiota is given. Alternative approaches to the treatment of depression are being considered by balancing the microbial composition through dietary modifications and the use of additives, namely probiotics, postbiotics (including vesicles) and prebiotics as psychobiotics, and fecal transplantation. The bacterium Faecalibacterium prausnitzii is under consideration as a promising new-generation probiotic and auxiliary diagnostic biomarker of depression. The analysis conducted in this review may be useful for clinical practice and pharmacology.

Gut Microbiota Richness and Diversity Track With T Cell Aging in Healthy Adults

BACKGROUND

This study examined how gut microbiota diversity and richness relate to T cell aging among 96 healthy adults of all ages. It also explored whether these links differed throughout the lifespan.

METHODS

Peripheral blood was obtained from 96 study participants (N = 96, aged 21-72) to assess mRNA markers of T cell aging (p16ink4a, p14ARF, B3gat1, Klrg1) and DNA methylation. T cell aging mRNA markers were combined into an aging index, and the Horvath epigenetic clock algorithm was used to calculate epigenetic age based on DNA methylation status of over 500 loci. Participants also collected a stool sample from which the V4 region of the 16S rRNA gene was sequenced to derive the Shannon and Simpson diversity indices, and the total count of observed operational taxonomic units (richness). Models controlled for BMI, comorbidities, sex, dietary quality, smoking status, physical activity, and sleep quality.

RESULTS

Lower microbiota richness was associated with higher T cell age based on mRNA markers, but when probing the region of significance, this relationship was only significant among adults 45 years and older (p = .03). Lower Shannon diversity (p = .05) and richness (p = .07) marginally correlated with higher epigenetic age (ie, greater T cell DNA methylation).

CONCLUSIONS

Gut microbiota complexity may correspond with the rate of T cell aging, especially in mid-to-late life. These results suggest an interplay between the gut microbiome and immunological aging that warrants further experimental work.

The Muscle-Gut-Brain Axis and Psychiatric Illness

The microbiota-gut-brain axis (MGBA) has been the subject of much research over the past decade, offering an exciting new paradigm for the treatment of psychiatric disorders. In this review, the MGBA is extended to include skeletal muscle and the potential role of an expanded "muscle-gut-brain axis" (MuGBA) in conditions such as anxiety and depression is discussed. There is evidence, from both preclinical and human studies, of bidirectional links between the gut microbiome and skeletal muscle function and structure. The therapeutic role of exercise in reducing depressive and anxiety symptoms is widely recognised, and the potential role of the gut microbiota-skeletal muscle link is discussed within this context. Potential pathways of communication involved in the MuGBA including the tryptophan-kynurenine pathway, intestinal permeability, immune modulation, and bacterial metabolites such as short-chain-fatty-acids are explored.

Gut Microbiome-Brain Alliance: A Landscape View into Mental and Gastrointestinal Health and Disorders

Gut microbiota includes a vast collection of microorganisms residing within the gastrointestinal tract. It is broadly recognized that the gut and brain are in constant bidirectional communication, of which gut microbiota and its metabolic production are a major component, and form the so-called gut microbiome-brain axis. Disturbances of microbiota homeostasis caused by imbalance in their functional composition and metabolic activities, known as dysbiosis, cause dysregulation of these pathways and trigger changes in the blood-brain barrier permeability, thereby causing pathological malfunctions, including neurological and functional gastrointestinal disorders. In turn, the brain can affect the structure and function of gut microbiota through the autonomic nervous system by regulating gut motility, intestinal transit and secretion, and gut permeability. Here, we examine data from the CAS Content Collection, the largest collection of published scientific information, and analyze the publication landscape of recent research. We review the advances in knowledge related to the human gut microbiome, its complexity and functionality, its communication with the central nervous system, and the effect of the gut microbiome-brain axis on mental and gut health. We discuss correlations between gut microbiota composition and various diseases, specifically gastrointestinal and mental disorders. We also explore gut microbiota metabolites with regard to their impact on the brain and gut function and associated diseases. Finally, we assess clinical applications of gut-microbiota-related substances and metabolites with their development pipelines. We hope this review can serve as a useful resource in understanding the current knowledge on this emerging field in an effort to further solving of the remaining challenges and fulfilling its potential.

Gut Microbiota in Anxiety and Depression: Unveiling the Relationships and Management Options

The gut microbiota is critical for maintaining human health and the immunological system. Several neuroscientific studies have shown the significance of microbiota in developing brain systems. The gut microbiota and the brain are interconnected in a bidirectional relationship, as research on the microbiome-gut-brain axis shows. Significant evidence links anxiety and depression disorders to the community of microbes that live in the gastrointestinal system. Modified diet, fish and omega-3 fatty acid intake, macro- and micro-nutrient intake, prebiotics, probiotics, synbiotics, postbiotics, fecal microbiota transplantation, and 5-HTP regulation may all be utilized to alter the gut microbiota as a treatment approach. There are few preclinical and clinical research studies on the effectiveness and reliability of various therapeutic approaches for depression and anxiety. This article highlights relevant research on the association of gut microbiota with depression and anxiety and the different therapeutic possibilities of gut microbiota modification.

Mechanistic Insights into the Link between Gut Dysbiosis and Major Depression: An Extensive Review

Depression is a highly common mental disorder, which is often multifactorial with sex, genetic, environmental, and/or psychological causes. Recent advancements in biomedical research have demonstrated a clear correlation between gut dysbiosis (GD) or gut microbial dysbiosis and the development of anxiety or depressive behaviors. The gut microbiome communicates with the brain through the neural, immune, and metabolic pathways, either directly (via vagal nerves) or indirectly (via gut- and microbial-derived metabolites as well as gut hormones and endocrine peptides, including peptide YY, pancreatic polypeptide, neuropeptide Y, cholecystokinin, corticotropin-releasing factor, glucagon-like peptide, oxytocin, and ghrelin). Maintaining healthy gut microbiota (GM) is now being recognized as important for brain health through the use of probiotics, prebiotics, synbiotics, fecal microbial transplantation (FMT), etc. A few approaches exert antidepressant effects via restoring GM and hypothalamus–pituitary–adrenal (HPA) axis functions. In this review, we have summarized the etiopathogenic link between gut dysbiosis and depression with preclinical and clinical evidence. In addition, we have collated information on the recent therapies and supplements, such as probiotics, prebiotics, short-chain fatty acids, and vitamin B12, omega-3 fatty acids, etc., which target the gut–brain axis (GBA) for the effective management of depressive behavior and anxiety.

Stressor-Induced Reduction in Cognitive Behavior is Associated with Impaired Colonic Mucus Layer Integrity and is Dependent Upon the LPS-Binding Protein Receptor CD14

Purpose

Commensal microbes are impacted by stressor exposure and are known contributors to cognitive and social behaviors, but the pathways through which gut microbes influence stressor-induced behavioral changes are mostly unknown. A murine social stressor was used to determine whether host-microbe interactions are necessary for stressor-induced inflammation, including neuroinflammation, that leads to reduced cognitive and social behavior.

Methods

C57BL/6 male mice were exposed to a paired fighting social stressor over a 1 hr period for 6 consecutive days. Y-maze and social interaction behaviors were tested following the last day of the stressor. Serum cytokines and lipopolysaccharide binding protein (LBP) were measured and the number and morphology of hippocampal microglia determined via immunohistochemistry. Intestinal mucous thickness and antimicrobial peptide expression were determined via fluorescent staining and real-time PCR (respectively) and microbial community composition was assessed using 16S rRNA gene amplicon sequencing. To determine whether the microbiota or the LBP receptor (CD14) are necessary for stressor-induced behavioral changes, experiments were performed in mice treated with a broad-spectrum antibiotic cocktail or in CD14-/- mice.

Results

The stressor reduced Y-maze spontaneous alternations, which was accompanied by increased microglia in the hippocampus, increased circulating cytokines (eg, IL-6, TNF-α) and LBP, and reduced intestinal mucus thickness while increasing antimicrobial peptides and cytokines. These stressor-induced changes were largely prevented in mice given broad-spectrum antibiotics and in CD14-/- mice. In contrast, social stressor-induced alterations of social behavior were not microbe-dependent.

Conclusion

Stressor-induced cognitive deficits involve enhanced bacterial interaction with the intestine, leading to low-grade, CD14-dependent, inflammation.

The gut connection: Intestinal permeability as a pathway from breast cancer survivors' relationship satisfaction to inflammation across treatment

BACKGROUND

Breast cancer survivors are prone to weakened gut barriers, allowing bacteria to migrate into the blood stream. Gut permeability fuels inflammation, which, among survivors, can elevate risk for comorbid disease development, cancer recurrence, and a poor quality of life; however, survivors' satisfying relationships can provide health benefits. This longitudinal study used a conceptual model addressing how intimate relationships is associated with health through changes in gut permeability and inflammation.

METHOD

Breast cancer survivors (n = 139, stages 0-IIIC) completed a baseline visit before treatment and two follow-up visits 6 and 18 months after treatment ended. Women who had an abnormal breast cancer test followed by a benign diagnosis completed visits within a comparable timeframe (noncancer patient controls; n = 69). All women completed questionnaires assessing their relationship satisfaction and provided blood samples to assess two bacterial endotoxin biomarkers, lipopolysaccharide-binding protein (LBP) and soluble CD14 (sCD14), as well as C-reactive protein (CRP) and interleukin 6 (IL-6).

RESULTS

Within-person multilevel mediation analyses showed that when a survivor's relationship satisfaction was higher than usual, her own LBP and LBP/sCD14 were lower, which was associated with lower than her own average CRP and IL-6 (95% CIs [-0.0104, -0.0002]). IL-6 was also higher when older survivors, but not younger survivors, experienced higher than usual intestinal permeability (p = .001). These effects of satisfying relationships held after accounting for cancer-related and behavioral factors. Post-hoc analyses showed LBP, sCD14, and LBP/sCD14 were associated with CRP for the cancer survivors, but only LBP and LBP/sCD14 were linked to CRP among the noncancer control patients.

CONCLUSION

The gut environment is a new promising candidate for understanding a relationship's long-term health impact, particularly among those with elevated health risks. Survivors may reap multiple physiological benefits from satisfying relationships.

Earth Dreams: Reimagining ARPA for Health of People, Places and Planet

Bold new approaches are urgently needed to overcome global health challenges. The proposed Advanced Research Projects Agency for Health (ARPA-H) is intended to provide rapid health breakthroughs. While new technologies for earlier disease detection and more effective treatment are critical, we urge equal attention be given to the wider (physical, emotional, social, political, and economic) environmental ecosystems driving the non-communicable disease (NCD) crisis in the first place. This requires an integrated, cross-sectoral vision that spans the interwoven connections affecting health across the scales of people, places, and planet. This wider "exposome" perspective considers biopsychosocial factors that promote resilience and reduce vulnerabilities of individuals and communities over time-the many variables driving health disparities. Since life course health is strongly determined by early life environments, early interventions should be prioritized as a matter of effectiveness and social justice. Here, we explore the origins of the Advanced Research Project Agency and point to its potential to build integrated solutions, with wisdom and ethical value systems as a compass. Since the planned ARPA-H is anticipated to spawn international collaborations, the imagined concept is of relevance to a broad audience of researchers. With appropriate input, the quest for health equity through personalized, precision medicine while deconstructing unacceptable structural inequities may be accelerated.

The health consequences of stress in couples: A review and new integrated Dyadic Biobehavioral Stress Model

Despite marriage's health benefits, all couples experience stress that can increase morbidity and mortality risks. Marital stress can alter endocrine, cardiovascular, and immune function-key pathways from troubled relationships to poor health. This review discusses how partners "get under each other's skin" to influence psychological, behavioral, and biological health. Then, I offer a comprehensive Dyadic Biobehavioral Stress Model to build on this foundational work and inspire transdisciplinary research integrating psychoneuroimmunological and relational lenses. This conceptual and empirically driven model provides promising new directions to investigate mechanisms linking individuals' relationships behaviors to their own and their partners' health, with particular emphasis on biological pathways. These mechanisms may impact each partner's physical health outcomes, such as disease development, illness severity, and accelerated biological aging. Risk and protective factors across developmental stages and diverse contexts are also discussed to help explain how, and under what conditions, partners influence each other's health. Research applying this model can push the boundaries of our current understanding on dyadic stress its far-reaching health effects on self-report and biological markers across the lifespan.