The research team, led by investigators affiliated with Heilongjiang University of Chinese Medicine, took an unusually systematic approach. Because PCOS is a heterogeneous, multifactorial disorder and because traditional herbal formulas contain dozens of chemically active compounds acting on many targets simultaneously, the researchers first turned to network pharmacology. This computational strategy treats a disease and a drug as vast interaction networks and searches for the points where they overlap. The team screened the chemical constituents of BHF’s five herbs—Huang Qi (Astragalus membranaceus), Yin Yang Huo (Herba epimedii), Cang Zhu (Rhizoma atractylodis), Fu Ling (Poria cocos), and Dan Shen (Salvia miltiorrhiza)—using the TCMSP database, applying strict filters for oral bioavailability and drug-likeness. The screen yielded 101 active chemical components and 218 predicted protein targets.

Cross-referencing those drug targets against 5,836 PCOS-related targets harvested from the GeneCards and OMIM databases produced a set of 169 intersecting targets. From there, the researchers built a herb–component–target network in Cytoscape and ranked the ingredients by their degree values, a topological measure of how many other network nodes a given compound connects to. Luteolin, a flavonoid with 116 connections, topped the list, followed by wogonin, tanshinone IIA, formononetin, isorhamnetin, and several other molecules with documented anti-inflammatory and metabolic activity. Protein–protein interaction analysis then distilled the target network down to ten hub proteins: AKT1, TNF, IL6, TP53, ESR1, CASP3, EGFR, IL1B, PTGS2, and MMP9—names that will be immediately familiar to anyone who studies inflammation, apoptosis, insulin signaling, or ovarian steroidogenesis.

Enrichment analysis added a pathway-level view. The intersecting targets clustered in the AGE-RAGE signaling pathway in diabetic complications, the IL-17 and MAPK pathways, estrogen signaling, insulin resistance, and—most relevant to this study—the NF-κB signaling pathway. To probe whether the predicted compounds could actually engage their predicted targets, the team performed molecular docking with AutoDock Vina across one hundred compound–protein pairs. Sixty-six of these interactions showed strong binding affinity below −7.0 kcal/mol, indicating thermodynamically stable ligand–receptor complexes. Notably, tanshinone IIA, a diterpenoid from Dan Shen, bound PTGS2—the gene encoding cyclooxygenase-2—more tightly than any other pairing tested, flagging it as a potential lead compound.

Computational predictions, however, are only hypotheses until they meet wet-lab reality. To validate the network findings, the researchers used letrozole, an aromatase inhibitor, to induce PCOS in female Wistar rats via continuous-release pellets. Critically, they examined the animals at two time points—six weeks and twelve weeks after pellet implantation—to capture the dynamic evolution of the disease rather than a single endpoint. The letrozole model reproduced the metabolic and reproductive abnormalities seen in clinical PCOS: treated rats gained significantly more weight, accumulated more inguinal fat, and showed elevated fasting blood glucose compared with controls, with all measures worsening between the six- and twelve-week marks. Histology told a parallel story. While the ovaries of early-stage rats looked largely normal, the twelve-week group developed frank cystic follicular dilation, follicular atresia, and thinning of the granulosa cell layers—textbook signs of established PCOS.

The inflammatory signature emerged early and deepened over time. Immunohistochemistry revealed increased TLR4 and NF-κB protein staining in both ovarian and inguinal fat tissues of the twelve-week model, and a qPCR array of ninety-two NF-κB signaling targets detected significant shifts in genes including ACTB, C3, CXCL3, NQO1, and SELP. When the team isolated granulosa cells—the somatic cells that nurture developing oocytes and are essential for ovulation—they found dramatically elevated secretion of TNF-α, IL-1β, IL-6, IL-8, lipopolysaccharide-binding protein, LPS itself, CD14, and high-sensitivity C-reactive protein. Several of these markers, including IL-1β, IL-6, IL-8, and LPS, rose further between the six- and twelve-week stages, confirming that the inflammatory microenvironment of the PCOS ovary is not static but progressively escalating. The LPS–LBP–CD14 module is particularly significant mechanistically, because this triad is the canonical activator of TLR4, the innate immune receptor that switches on NF-κB and triggers the transcriptional program of chronic inflammation.

Enter the herbal formula. The researchers prepared BHF-containing serum by dosing healthy rats with the decoction and collecting their blood, then co-cultured this serum with granulosa cells isolated from the PCOS animals. The results were striking. In cells from six-week PCOS rats, BHF serum significantly reduced all eight inflammatory markers compared with cells treated with control serum, essentially reversing the heightened inflammatory state. In cells from twelve-week rats, BHF again lowered TNF-α, IL-1β, IL-6, IL-8, LBP, LPS, CD14, and hsCRP—but the reduction was only partial, and treated diseased cells still secreted significantly more inflammatory factors than treated healthy cells. In other words, the formula could suppress inflammation at both stages, but early-stage disease responded far more completely.

This stage-dependence is arguably the study’s most important translational message. It suggests that the chronic low-grade inflammatory state in PCOS precedes the full establishment of the syndrome and may actively contribute to its progression, and that therapeutic windows matter: once the inflammatory loop becomes entrenched, even a multi-target intervention cannot fully unwind it. The finding echoes a core principle of traditional Chinese medicine—“preventing disease before it progresses”—and aligns with the modern concept of early intervention in chronic inflammatory and metabolic disease. Because NF-κB sits at the hub of the cytokine network, feeding back on its own activation through TNF-α and sustaining IL-6 signaling via JAK/STAT3, breaking the loop early may prevent the self-perpetuating inflammation that disrupts granulosa cell steroidogenesis and ultimately ovulation itself.

The authors are appropriately candid about the limitations. The work was conducted entirely in rats and isolated cells; the letrozole model recapitulates only part of the heterogeneous human phenotype; TLR4/NF-κB activation was assessed by immunohistochemistry and gene expression rather than phospho-specific or loss-of-function experiments, so causation remains to be proven; the formula batch was not chemically fingerprinted; and hormonal endpoints such as testosterone and estrous cyclicity were not measured. Human validation—in granulosa cells, follicular fluid, and clinical cohorts—is the essential next step. Still, the convergence of computational prediction, molecular docking, and experimental data provides a rare level of mechanistic coherence for a multi-herb formula. If confirmed, BHF’s ability to modulate the TLR4/NF-κB axis could open a genuinely new direction for managing the inflammatory component of PCOS, one rooted in centuries of empirical practice but tested with thoroughly modern tools.

Subject of Research: Effects of the Bushen Huatan Formula on chronic low-grade inflammation in obese PCOS via the TLR4/NF-κB signaling pathway

Article Title: Bushen Huatan Formula Ameliorates Early Chronic Low‐Grade Inflammation in Obese PCOS Via the TLR4/NF‐κB Signaling Pathway: An Integrated Network Pharmacology and Experimental Study

Article References: Zhang, J., Gu, F., Li, Y., Feng, X., Kuang, H., Xu, F., & Sun, M. (2026). Bushen Huatan Formula Ameliorates Early Chronic Low‐Grade Inflammation in Obese PCOS Via the TLR4/NF‐κB Signaling Pathway: An Integrated Network Pharmacology and Experimental Study. Immunity, Inflammation and Disease, 14(9), Article e70518. https://doi.org/10.1002/iid3.70518

Image Credits: AI Generated

DOI: 10.1002/iid3.70518

Keywords: PCOS, chronic low-grade inflammation, Bushen Huatan Formula, TLR4/NF-κB pathway, network pharmacology, molecular docking, granulosa cells, traditional Chinese medicine, letrozole-induced rat model, inflammatory cytokines, ovarian inflammation, insulin resistance

Inflammation is one of the hallmarks of cancer biology. Long before a tumour becomes clinically detectable, the tumour microenvironment is often populated by immune cells, cytokines and other signalling molecules that can, under certain conditions, support tumour initiation and progression. Epidemiologists have therefore long been interested in whether markers of systemic inflammation measured in the blood, such as C-reactive protein and various circulating cytokines, might serve as early warning signals of future cancer risk. If such associations could be established robustly, they might open the door to risk stratification, earlier surveillance and, ultimately, prevention strategies targeted at women whose inflammatory profiles place them at elevated risk.

Breast cancer is not a single disease but a collection of biologically distinct subtypes, defined in large part by the presence or absence of hormone receptors and by expression of the HER2 protein. Oestrogen receptor-positive tumours are the most common subtype, particularly among postmenopausal women, and their growth is fuelled by oestrogen signalling. Because both inflammation and oestrogen signalling are influenced by shared factors such as adiposity, age and metabolic health, researchers have hypothesised that inflammatory processes may interact with hormonal pathways in ways that are especially relevant to this subtype. Testing that hypothesis requires large, well-characterised cohorts of postmenopausal women followed over long periods, with blood samples collected before any cancer diagnosis.

The case-cohort design adopted by the study is a methodologically important choice. In a classic prospective cohort study, every participant would be followed and their biomarkers measured, an approach that becomes prohibitively expensive when thousands of blood samples must be assayed for multiple inflammatory markers. A case-cohort design offers an efficient alternative: researchers identify all the women in the cohort who went on to develop the cancer of interest, the cases, and compare them with a randomly selected subcohort drawn from the full study population, regardless of disease status. Because the subcohort is randomly sampled, it provides an unbiased estimate of the underlying distribution of biomarker levels in the population at risk, and the resulting statistical models can yield risk estimates that closely approximate those of a full cohort analysis at a fraction of the laboratory cost.

This efficiency comes with analytical subtleties that the researchers had to navigate. Case-cohort analyses require specialised statistical techniques, most commonly variants of the Cox proportional hazards model with weighted pseudo-likelihood approaches, to account for the overlapping structure of the case group and the subcohort. Confounding is a persistent concern in observational biomarker research: systemic inflammation is correlated with body mass index, smoking, physical inactivity, diabetes and a range of other lifestyle and metabolic factors that themselves influence breast cancer risk. A credible analysis must therefore adjust carefully for these covariates, while also considering the possibility that some of the association between inflammation and cancer operates precisely through those intermediary conditions, making over-adjustment as much a hazard as residual confounding.

Timing is another critical consideration. Inflammatory biomarkers measured in blood samples donated years before diagnosis are generally more informative than those measured close to diagnosis, because a developing, undiagnosed tumour can itself elevate circulating inflammatory markers, creating reverse causation. Studies of this kind typically address the problem by excluding cases diagnosed within the first year or two of follow-up, or by demonstrating that associations persist when early diagnoses are removed. The strength of any prospective biomarker study rests on how convincingly it handles this temporal ambiguity, and readers interpreting the findings should pay close attention to the sensitivity analyses the authors report.

The biological rationale linking inflammation specifically to oestrogen receptor-positive disease is worth unpacking. Adipose tissue, particularly visceral fat abundant after menopause, is not merely a passive energy store but an active endocrine organ that secretes pro-inflammatory cytokines and is a major site of oestrogen synthesis in postmenopausal women through the enzyme aromatase. Chronic inflammatory signalling can promote cell proliferation, inhibit apoptosis, stimulate angiogenesis and generate DNA-damaging reactive oxygen species, all of which are processes plausibly relevant to tumour development. At the same time, oestrogen itself modulates immune responses, meaning the two systems are deeply intertwined. Disentangling whether inflammation independently predicts hormone receptor-positive breast cancer, or merely tracks along with adiposity and metabolic dysfunction, is precisely the kind of question a well-powered case-cohort analysis is positioned to address.

For the wider field, the significance of the study lies less in any single risk estimate than in the accumulation of evidence across diverse populations and designs. Previous prospective investigations of inflammatory markers and breast cancer have reported inconsistent findings, with some observing modest positive associations for overall or hormone receptor-defined disease and others finding little or no association once body size was accounted for. These inconsistencies may reflect differences in the biomarkers measured, the assays used, the length of follow-up, the degree of postmenopausal hormone therapy use in the underlying populations, or genuine heterogeneity across populations. Each new, rigorously conducted analysis helps to narrow the range of plausible effects and to identify the conditions under which inflammatory biomarkers do or do not add predictive value beyond established risk factors.

Clinically, the stakes are considerable. Breast cancer risk prediction models currently rely on combinations of demographic, reproductive, hormonal and familial factors, and increasingly on polygenic risk scores. If validated inflammatory biomarkers were shown to meaningfully improve risk discrimination, they could help identify postmenopausal women who might benefit from intensified screening, lifestyle interventions aimed at reducing systemic inflammation, or, in selected high-risk groups, preventive endocrine therapy. Conversely, if inflammatory markers add little once adiposity and metabolic health are fully accounted for, that too is an important result, redirecting attention toward the modifiable upstream factors that drive both inflammation and cancer risk.

The study also underscores a broader lesson in modern cancer epidemiology: subtype matters. Pooling all breast cancers together can dilute or mask associations that are specific to particular molecular subgroups, and analyses restricted to oestrogen receptor-positive disease represent a step toward the kind of aetiological precision the field increasingly demands. As researchers continue to mine pre-diagnostic blood samples with ever more sensitive multiplex assays, including measures of chronic immune activation and emerging markers of inflammageing, studies of this design will remain central to determining whether the inflammatory fingerprint measurable in a routine blood draw can ever become part of practical cancer risk assessment. For now, the new case-cohort analysis offers a methodologically sound contribution to that ongoing effort, and a reminder that the biology linking inflammation, hormones and cancer is as intricate as it is important.

Subject of Research: Association between circulating inflammatory biomarkers and the risk of postmenopausal oestrogen receptor-positive breast cancer

Article Title: Inflammatory biomarkers and risk of postmenopausal oestrogen receptor-positive breast cancer: a case-cohort analysis

Article References: Inflammatory biomarkers and risk of postmenopausal oestrogen receptor-positive breast cancer: a case-cohort analysis. (n.d.). https://doi.org/10.1038/s41416-026-03624-6

Image Credits: AI Generated

DOI: 10.1038/s41416-026-03624-6

Keywords: inflammatory biomarkers, breast cancer, postmenopausal women, oestrogen receptor-positive, case-cohort analysis, C-reactive protein, chronic inflammation, cancer epidemiology, risk prediction, adiposity, cytokines, British Journal of Cancer

Immunosenescence is far more than a simple decline in immune vigor. It is a sweeping remodeling of both the innate and adaptive arms of immunity, marked by a shrinking pool of naive T cells, an accumulation of exhausted memory cells, a narrowing of T-cell receptor diversity, and a chronic, low-grade inflammatory state often called inflammaging. These changes are closely tied to impaired immunometabolism, mitochondrial dysfunction, and shifts in key signaling networks, including the AMPK/mTOR axis, the NF-kappaB pathway, autophagy, and the NLRP3 inflammasome. Because no single molecular defect drives the process, the authors contend that a multi-target agent may be better suited to intervene than highly specific drugs aimed at one pathway at a time.

Berberine, an isoquinoline alkaloid extracted from plants such as Berberis vulgaris, has been used in traditional Chinese and Ayurvedic medicine for centuries. Modern pharmacology has mapped an impressive array of its molecular actions: it activates AMP-activated protein kinase (AMPK) partly by inhibiting mitochondrial respiratory complex I, suppresses mTOR signaling, modulates NF-kappaB-driven inflammation, promotes autophagy, and inhibits NLRP3 inflammasome activation. Each of these targets sits squarely at the intersection of the pathways that go awry during immunosenescence. Clinical evidence already supports berberine’s benefits in cardiometabolic disease, including type 2 diabetes, nonalcoholic fatty liver disease, and metabolic syndrome, and a phase 2 trial of berberine ursodeoxycholate showed proof of concept in patients with non-alcoholic steatohepatitis and type 2 diabetes.

The review assembles evidence from cellular, animal, and early human studies that speaks directly to immune aging. In cell culture, berberine suppresses gero-conversion, the transition from reversible cell-cycle arrest to full senescence, and protects cells from oxidative stress-induced senescence through AMPK activation, restoration of autophagic flux, and elevation of intracellular NAD+. In mice, the compound ameliorates cellular senescence and extends lifespan by regulating p16 and cyclin protein expression. In simpler organisms, berberine prolongs lifespan and stimulates locomotor activity in Drosophila melanogaster and extends lifespan in Caenorhabditis elegans through multi-target antioxidant effects and ROS-dependent activation of the PMK-1/SKN-1 stress-response pathway.

Particularly relevant to immune aging are berberine’s documented effects on inflammatory signaling. The compound inhibits LPS-induced inflammatory responses through the NF-kappaB pathway, blocks NLRP3 inflammasome activation in macrophages by triggering autophagy and regulating the mTOR/mitochondrial ROS axis, and reduces SASP-related inflammation through the RXRalpha/PPARgamma/NEDD4 pathway in models of atherosclerosis. It also modulates sirtuin 1 activity, a deacetylase implicated in immune cell longevity, and enhances innate antiviral defenses via the p38 MAPK pathway, with demonstrated anti-influenza activity in mice. Because the senescence-associated secretory phenotype, or SASP, is a major driver of chronic age-related inflammation, a drug that dampens SASP output while simultaneously supporting autophagy and mitochondrial quality control addresses several hallmarks of immune aging at once.

The review also highlights a newer generation of berberine derivatives engineered to overcome the parent compound’s most stubborn limitation: poor oral bioavailability. Berberine is poorly absorbed from the gut, relies partly on gut microbiota transformation into the intestine-absorbable form dihydroberberine, and is subject to efflux by P-glycoprotein. Chemists have responded with 8,8-dimethyldihydroberberine, 9-O-substituted and 9-N-alkyl derivatives, liposomal and nanoparticle formulations, and self-microemulsifying delivery systems, all of which improve absorption in animal or human studies. Some derivatives add entirely new capabilities: a 13-decyl berberine derivative has been described as a novel mitochondria-targeted antioxidant and potent inhibitor of ferroptosis, while tetrahydroberberrubine retards heart aging in mice by promoting PHB2-mediated mitophagy, and berberrubine-based mitorubin compounds improve mitochondrial function and protect against age-related cardiac dysfunction.

Yet the authors are careful to temper enthusiasm with critical caveats. Much of the immunosenescence-relevant evidence comes from in vitro work or from animal models whose immune systems differ substantially from aged humans. Direct clinical trials testing berberine specifically against immunosenescence biomarkers, such as T-cell receptor repertoire diversity, p16INK4a expression in peripheral blood T cells, senescence-associated beta-galactosidase in CD8+ T cells, or inflammatory aging clocks like iAge, have not been performed. Safety considerations also warrant attention: berberine inhibits cytochrome P450 enzymes in humans, raising drug-interaction risks, and it has been shown to alter blood levels of immunosuppressants such as cyclosporin A in transplant recipients. Its interaction with the adenine nucleotide translocator and complex I inhibition, while mechanistically central to AMPK activation, could be a double-edged sword in metabolically stressed immune cells.

To move the field forward, the review proposes a framework for future studies. The authors call for properly designed experiments in aged animal models that measure established immunosenescence biomarkers rather than generic inflammation endpoints, followed by carefully monitored human trials in older populations. They emphasize the value of modern immune-aging metrics, including single-cell immune aging clocks that capture inter-individual heterogeneity during infection and vaccination, and suggest that derivatives with improved bioavailability and mitochondrial targeting should be prioritized. Vaccine responsiveness in the elderly, which is notoriously blunted and linked to T-cell autophagy decline, is identified as a clinically meaningful outcome that a berberine-based intervention could plausibly improve.

The broader significance of the analysis lies in its reframing of an old herbal medicine as a systems-level geroprotector. Where most anti-aging pharmacology pursues single targets, berberine’s pleiotropy, acting simultaneously on energy sensing, inflammatory transcription, autophagy, inflammasome activity, and mitochondrial function, mirrors the interconnected nature of immune aging itself. Whether that pleiotropy translates into safe and measurable rejuvenation of the human immune system remains an open question, but the review provides the mechanistic rationale and the experimental roadmap needed to find out. If subsequent trials validate the promise, a compound once confined to traditional apothecaries could become a cornerstone of interventions designed to keep aging immune systems, and the aging populations they protect, healthier for longer.

Subject of Research: Evaluation of berberine and its derivatives as multi-target modulators of age-related immune system decline (immunosenescence).

Article Title: Berberine and its derivatives as candidate modulators of immunosenescence: a critical evaluation

Article References: Zinovkin, R. A., Lyamzaev, K. G., Churov, A., Maltseva, O., & Wu, Z. (2026). Berberine and its derivatives as candidate modulators of immunosenescence: a critical evaluation. Biogerontology, 27(5), Article 153. https://doi.org/10.1007/s10522-026-10504-2

Image Credits: AI Generated

DOI: 10.1007/s10522-026-10504-2

Keywords: berberine, immunosenescence, aging, AMPK, mTOR, NF-kappaB, autophagy, NLRP3 inflammasome, inflammaging, mitochondria, berberine derivatives, geroprotection

Unlike adaptive immune memory, which is associated mainly with B cells and T cells, trained immunity describes a long-lasting functional change in innate immune cells. The innate immune system responds rapidly to threats without relying on the highly specific receptors used by adaptive immunity. After exposure to infections, vaccines, inflammatory signals or other stressors, innate immune cells and their precursors can become “trained,” responding more strongly to a later challenge. This phenomenon can improve protection against unrelated pathogens, but the new study highlights how persistent or improperly regulated training may turn into a liability over time.

The proposed connection begins in the bone marrow, where hematopoietic stem cells, or HSCs, reside in specialized microenvironments known as niches. HSCs are normally maintained in a relatively quiet state, dividing only when new blood cells are needed. During infection or tissue injury, inflammatory cytokines and other danger signals can activate these cells and redirect blood production toward myeloid cells, including monocytes, macrophages and neutrophils. This emergency response is useful in the short term. However, repeated or prolonged exposure to inflammatory signals may leave a durable imprint on HSCs, changing how they behave even after the original threat has disappeared.

That imprint can involve several layers of cellular regulation. Inflammatory stimulation may alter chromatin, the DNA-protein structure that controls access to genes, as well as DNA methylation, metabolic pathways and the activity of transcription factors. These changes can influence which genes are switched on when an HSC produces descendants. A stem cell affected by trained immunity may therefore generate blood cells with an enhanced tendency to produce inflammatory mediators. Over years, this could create a self-reinforcing system in which inflammation modifies stem cells, and the altered stem cells continually replenish inflammatory immune populations.

This mechanism offers a framework for understanding why aging is accompanied by a gradual shift in blood-cell production. With advancing age, HSC populations often become more heterogeneous and may favor myeloid output over the generation of lymphoid cells. The result can be a larger supply of innate immune cells alongside a weaker capacity to produce certain lymphocytes, contributing to an immune system that is simultaneously more inflammatory and less adaptable. The authors’ concept of maladaptive trained immunity places this imbalance upstream, suggesting that long-term changes in stem-cell behavior may help organize the broader immune dysfunction seen in older adults.

The idea also overlaps with research into clonal hematopoiesis, a process in which genetically or epigenetically altered HSCs expand and produce a substantial fraction of a person’s blood cells. Some of these clones carry mutations in genes involved in epigenetic control or inflammatory signaling. Their descendants can release elevated levels of cytokines such as interleukin-1 beta and interleukin-6, molecules that help coordinate immune responses but can damage tissues when persistently produced. Trained immunity and clonal hematopoiesis are not identical, yet both illustrate how long-lived changes in HSCs can influence the inflammatory state of the entire body.

The proposed model may help explain why inflammation can persist without a continuing infection. In younger individuals, inflammatory responses are generally followed by resolution, a coordinated process involving anti-inflammatory signals, tissue repair and the removal of activated cells. Aging can weaken these resolution pathways while increasing exposure to inflammatory stimuli from damaged tissues, altered gut microbes, metabolic stress and recurrent infections. If HSCs retain a memory of these pressures, the bone marrow may continue producing immune cells primed for aggressive responses. The immune system would then remain prepared for danger, but at the cost of damaging healthy tissues.

The implications extend beyond basic immunology. If maladaptive trained immunity is a major driver of inflammaging, interventions might need to target the bone marrow and HSC regulatory networks rather than suppress inflammation throughout the body. Possible strategies could include selectively interrupting inflammatory cytokine signaling, restoring metabolic or epigenetic balance in HSCs, improving the bone-marrow niche, or reducing the expansion of harmful blood-cell clones. Such approaches would require caution because completely blocking trained immunity could impair protection against infection and weaken beneficial vaccine responses. The challenge would be to distinguish protective immune memory from the persistent, pathological form described by the authors.

The study also points toward new ways of studying biological age. Blood-cell composition, inflammatory proteins, HSC activity and epigenetic signatures could potentially be combined to identify people whose immune systems have entered a maladaptive state. Future research will need to determine how permanent trained-immunity signals are, whether they can be reversed, and which exposures are most important in establishing them. By placing hematopoietic stem cells at the center of the inflammaging process, Divangahi and King provide a unifying hypothesis: the aging immune system may not simply become weaker, but may be actively reprogrammed by its history of inflammatory encounters. Understanding that history could become essential to slowing age-related disease while preserving the immune system’s ability to respond when real threats arrive.

Subject of Research: Hematopoietic stem cells, trained immunity, inflammaging and age-related immune dysfunction

Article Title: Maladaptive trained immunity as a hematopoietic stem cell driver of inflammaging

Article References: Divangahi, M., King, K.Y. Maladaptive trained immunity as a hematopoietic stem cell driver of inflammaging. Nat Aging (2026). https://doi.org/10.1038/s43587-026-01197-w

Image Credits: AI Generated

DOI: 10.1038/s43587-026-01197-w

Keywords: trained immunity, hematopoietic stem cells, inflammaging, aging, innate immunity, bone marrow, clonal hematopoiesis, inflammation, immune memory, cytokines

Endotoxemia, primarily triggered by translocated LPS derived from Gram-negative bacteria in the gut, is a pivotal pathogenic mechanism in the development of obesity, diabetes, and multifactorial metabolic diseases. Persistent systemic exposure to LPS provokes chronic low-grade inflammation, insulin resistance, and dysregulated lipid metabolism. While previous investigations acknowledged probiotics’ role in mitigating plasma LPS concentrations, the precise molecular pathways remained inadequately characterized.

In this context, Professor Liu’s team delved into the multifaceted “BAs-LPS” nexus, revealing distinct biochemical and immunometabolic pathways through which C. tenuis ameliorates host metabolic parameters. Employing a DIO mouse model, their research demonstrated that oral administration of this probiotic species significantly enhanced glucose tolerance and lipid profiles while attenuating inflammation markers concomitantly with a consistent reduction in circulating and hepatic LPS levels.

At the mechanistic level, the study reveals that C. tenuis represses the LPS-driven TLR4 (Toll-like receptor 4) signaling cascade, a well-known mediator of inflammatory responses and metabolic disturbances. By attenuating this pathway, C. tenuis indirectly restores metabolic homeostasis, suppressing downstream effectors involved in chronic inflammation and metabolic derangements. However, the novelty of this research lies in linking bile acid metabolism alterations induced by C. tenuis to its protective effects.

Comprehensive omics analyses uncovered that treatment with C. tenuis elevated the abundance of free bile acids in the gut, a critical shift from the predominance of conjugated bile acids typically seen in DIO conditions. In vitro experiments confirmed that C. tenuis possesses bile salt hydrolase (BSH) activity, enzymatically hydrolyzing conjugated bile acids into their free forms. This enzymatic activity reshapes the bile acid pool, altering intestinal milieu and systemic metabolic signals.

Further structural and biophysical investigations, including molecular dynamics simulations, elucidated that free bile acids form stable complexes with LPS molecules. These complexes are characterized by their non-permeability to cell membranes, effectively sequestering LPS within the gut lumen and preventing its translocation across the epithelial barrier into systemic circulation. This mechanism serves as a novel barrier-enhancing strategy that mitigates endotoxemia at its source.

Supporting these findings, isothermal titration calorimetry assays provided thermodynamic evidence of direct binding interactions between free bile acids and LPS. The binding process was demonstrated to be enthalpy-driven, suggesting strong molecular affinity and specificity. This quantitative biophysical validation corroborates computational models and signifies a robust interaction critical for inhibiting LPS absorption.

Remarkably, the team also conducted intervention experiments administering free bile acids alone to DIO mice. These treatments mimicked the probiotic’s effects by decreasing plasma LPS concentrations and improving metabolic indices, reinforcing the centrality of bile acid-mediated LPS sequestration as a universal and physiologically relevant mechanism.

This multi-disciplinary study, integrating microbiology, metabolomics, computational biology, and immunometabolism, substantially advances the understanding of gut barrier integrity regulation by probiotics. C. tenuis emerges not only as a beneficial commensal modulator of bile acid metabolism but also as a key agent capable of intercepting deleterious endotoxemia-related signaling pathways fundamental to metabolic disease pathogenesis.

The investigators propose that therapeutic strategies targeting the BAs-LPS axis, possibly through engineered probiotics or bile acid analogs, offer promising avenues for combating the global burden of obesity and its associated metabolic disorders. These findings highlight the importance of microbial-host co-metabolic interactions and suggest that modulation of gut microbial enzymatic functions may revolutionize gut-targeted intervention approaches.

This work was co-authored by Dr. Yu Jiang, Dr. Minzhi Jiang, and Dr. Jingyi Zhu, under the guidance of corresponding authors Professor Shuang-jiang Liu, Professor Chang Liu, and Associate Researcher Dr. Xukai Jiang. Their research marks a significant milestone in deciphering how gut microbiota-derived bile acid transformations can directly influence systemic inflammatory mediators and metabolic equilibrium.

By unveiling a previously unrecognized molecular mechanism wherein C. tenuis hydrolyzes bile acids to free forms that sequester LPS and prevent its systemic translocation, this study enriches the toolkit for future explorations into microbiome-based therapies. It underscores the therapeutic potential of precision modulation of gut metabolites and microbial enzymes to restore homeostasis disrupted by modern lifestyle-related diseases.

Ultimately, the study’s integration of in vivo, in vitro, and in silico methodologies provides a robust, multi-angle validation of the protective role of C. tenuis in metabolic health. It paves the way for innovative probiotic and bile acid-centered clinical applications designed to reduce metabolic endotoxemia and improve life quality for millions afflicted by obesity and related conditions.

Subject of Research:
Gut microbiota-probiotic interactions, bile acid metabolism, endotoxemia, and metabolic disorders.

Article Title:
Christensenella tenuis alleviates metabolic disorders by inhibiting gut LPS translocation.

News Publication Date:
Not specified.

Web References:
http://dx.doi.org/10.1007/s11427-025-3014-6

References:
Not explicitly detailed in the news content.

Image Credits:
©Science China Press

Keywords:
Christensenella tenuis, gut microbiota, bile acids, bile salt hydrolase, lipopolysaccharide, endotoxemia, metabolic disorders, diet-induced obesity, TLR4 signaling, probiotic therapy, gut barrier integrity, molecular dynamics simulation, isothermal titration calorimetry

Obesity and depression individually contribute massively to the global burden of disease, but their bidirectional relationship has long puzzled scientists. It is well-established that obesity increases the risk for depression, and conversely, depressive disorders can lead to weight gain. However, the biological underpinnings of this link have remained elusive. The study in question, encompassing 11,324 participants representative of over 450 million Americans, delved into this conundrum by focusing on systemic inflammation—a chronic, low-grade inflammatory state commonly observed in obesity—as a potential biological conduit.

The team adopted validated clinical metrics to gauge the severity of these conditions. Body Mass Index (BMI), the standard indicator for classifying obesity, was utilized to stratify participants. Depression was quantified using the Patient Health Questionnaire-9 (PHQ-9), a well-regarded self-report tool that captures the extent of depressive symptoms. To measure systemic inflammation’s multifaceted nature, the researchers employed innovative hematological markers: the Neutrophil-to-Lymphocyte Ratio (NLR), the Systemic Inflammation Response Index (SIRI), and the Systemic Immune-Inflammation Index (SII). These indices, derived from routine blood counts, provide insight into immune system dynamics and inflammatory status beyond conventional cytokine assays.

Analytical methods embraced weighted logistic regression models tailored to accommodate the NHANES complex sampling design. This approach allowed for robust examination of the associations between obesity, inflammation, and depression across the population. Linear regression analyses probed the dose-response relationship between BMI and inflammation markers, while Restricted Cubic Spline (RCS) analyses elegantly teased out potential non-linear trends in these biological interrelations. Subgroup analyses assessed whether factors such as age, sex, or ethnicity moderated these links, and interaction tests evaluated synergistic effects.

The results revealed a striking pattern: individuals classified with Class III obesity—the most severe obesity category characterized by a BMI of 40 or higher—exhibited significantly elevated levels of all three inflammatory markers and simultaneously showed a higher prevalence of depressive symptoms. These findings reinforce the hypothesis that systemic inflammation acts not merely as a correlate but potentially as a causal intermediate. Notably, mediation analyses quantified this contribution, with inflammation markers accounting for approximately 5-6% of the obesity-depression association, underscoring inflammation’s partial yet meaningful mediatory role.

What makes these findings compelling is the quantifiable mediation effect demonstrated for the NLR, SIRI, and SII metrics. Each index independently carried a modest but consistent mediation percentage, suggesting that systemic inflammation constitutes a biological pathway that partly explains how excess adiposity translates into neuropsychiatric manifestations like depression. This mechanistic insight opens avenues for targeted interventions aimed at mitigating inflammation as a means to disrupt this deleterious link.

The implications ripple through both clinical and public health domains. Obesity management has long focused on metabolic and cardiovascular endpoints, but this study highlights the necessity of integrating mental health perspectives and inflammatory biomarkers into comprehensive care paradigms. Conversely, therapeutic strategies addressing depression might benefit from concurrent attention to inflammatory status, particularly in patients with obesity, potentially enhancing treatment responses through personalized, biologically informed approaches.

Moreover, the utilization of hematological inflammation indices like NLR, SIRI, and SII offers practical and cost-effective tools for routine clinical assessment. Unlike specialized cytokine panels, these markers can be easily derived from standard complete blood counts, making them accessible for large-scale screening and longitudinal monitoring. The study’s demonstration of their mediatory role encourages their incorporation into future research and clinical workflows.

Despite the strengths of this expansive, nationally representative cohort, the study design remains observational, inherently limiting causal inferences. Bidirectionality and residual confounding cannot be entirely excluded. Longitudinal and interventional studies are warranted to validate and extend these findings, particularly to ascertain whether reducing systemic inflammation in obese individuals diminishes depressive symptomatology or prevents its onset.

Furthermore, delineating the molecular and cellular mechanisms by which systemic inflammation impacts brain function remains a critical research frontier. Chronic inflammation may alter neurotransmitter systems, neuroplasticity, and stress axis regulation, providing plausible biological substrates for depression. Elucidating these pathways at the mechanistic level will enable the development of novel therapeutics that target both obesity-driven inflammation and neuropsychiatric symptoms simultaneously.

In conclusion, this seminal investigation reinforces systemic inflammation as a key mediator in the empathetic relationship between obesity and depression. By confirming that heightened inflammatory states partially explain the increased risk of depression in severely obese individuals, the study paves the way for integrated strategies combining metabolic, immunological, and psychiatric care. As the global burden of these intertwined conditions continues to escalate, such multidisciplinary insights are urgently needed to inform effective prevention and treatment efforts.

This research represents a pivotal step toward decoding the complex interplay of body and mind, revealing that inflammation—the body’s silent alarm—might be the missing link connecting two of the most pressing health crises of our time. Future work inspired by these findings holds promise for reducing suffering and improving quality of life on a population scale through innovative, holistic medical paradigms.

Subject of Research: The role of systemic inflammation as a mediator in the relationship between obesity and depression.

Article Title: Systemic inflammation as a mediator in the link between obesity and depression: Evidence from a nationwide cohort study

Article References:
Wang, X., Liang, X., Jiang, M. et al. Systemic inflammation as a mediator in the link between obesity and depression: Evidence from a nationwide cohort study. BMC Psychiatry 25, 449 (2025). https://doi.org/10.1186/s12888-025-06892-3

Image Credits: AI Generated

DOI: https://doi.org/10.1186/s12888-025-06892-3