The development of artificial intelligence in the histological diagnosis of Inflammatory Bowel Disease (IBD-AI).

BACKGROUND: Inflammatory bowel disease (IBD) includes Crohn's Disease (CD) and Ulcerative Colitis (UC). Correct diagnosis requires the identification of precise morphological features such basal plasmacytosis. However, histopathological interpretation can be challenging, and it is subject to high variability. AIM: The IBD-Artificial Intelligence (AI) project aims at the development of an AI-based evaluation system to support the diagnosis of IBD, semi-automatically quantifying basal plasmacytosis. METHODS: A deep learning model was trained to detect and quantify plasma cells on a public dataset of 4981 annotated images. The model was then tested on an external validation cohort of 356 intestinal biopsies of CD, UC and healthy controls. AI diagnostic performance was calculated compared to human gold standard. RESULTS: The system correctly found that CD and UC samples had a greater prevalence of basal plasma cells with mean number of PCs within ROIs of 38.22 (95 % CI: 31.73, 49.04) for CD, 55.16 (46.57, 65.93) for UC, and 17.25 (CI: 12.17, 27.05) for controls. Overall, OR=4.968 (CI: 1.835, 14.638) was found for IBD compared to normal mucosa (CD: +59 %; UC: +129 %). Additionally, as expected, UC samples were found to have more plasma cells in colon than CD cases. CONCLUSION: Our model accurately replicated human assessment of basal plasmacytosis, underscoring the value of AI models as a potential aid IBD diagnosis.

Novel cellular systems unveil mucosal melanoma initiating cells and a role for PI3K/Akt/mTOR pathway in mucosal melanoma fitness.

BACKGROUND: Mucosal Melanomas (MM) are highly aggressive neoplasms arising from mucosal melanocytes. Current treatments offer a limited survival benefit for patients with advanced MM; moreover, the lack of pre-clinical cellular systems has significantly limited the understanding of their immunobiology. METHODS: Five novel cell lines were obtained from patient-derived biopsies of MM arising in the sino-nasal mucosa and designated as SN-MM1-5. The morphology, ultrastructure and melanocytic identity of SN-MM cell lines were validated by transmission electron microscopy and immunohistochemistry. Moreover, in vivo tumorigenicity of SN-MM1-5 was tested by subcutaneous injection in NOD/SCID mice. Molecular characterization of SN-MM cell lines was performed by a mass-spectrometry proteomic approach, and their sensitivity to PI3K chemical inhibitor LY294002 was validated by Akt activation, measured by pAkt(Ser473) and pAkt(Thr308) in immunoblots, and MTS assay. RESULTS: This study reports the validation and functional characterization of five newly generated SN-MM cell lines. Compared to the normal counterpart, the proteomic profile of SN-MM is consistent with transformed melanocytes showing a heterogeneous degree of melanocytic differentiation and activation of cancer-related pathways. All SN-MM cell lines resulted tumorigenic in vivo and display recurrent structural variants according to aCGH analysis. Of relevance, the microscopic analysis of the corresponding xenotransplants allowed the identification of clusters of MITF-/CDH1-/CDH2 + /ZEB1 + /CD271 + cells, supporting the existence of melanoma-initiating cells also in MM, as confirmed in clinical samples. In vitro, SN-MM cell lines were sensitive to cisplatin, but not to temozolomide. Moreover, the proteomic analysis of SN-MM cell lines revealed that RICTOR, a subunit of mTORC2 complex, is the most significantly activated upstream regulator, suggesting a relevant role for the PI3K-Akt-mTOR pathway in these neoplasms. Consistently, phosphorylation of NDRG1 and Akt activation was observed in SN-MM, the latter being constitutive and sustained by PTEN loss in SN-MM2 and SN-MM3. The cell viability impairment induced by LY294002 confirmed a functional role for the PI3K-Akt-mTOR pathway in SN-MM cell lines. CONCLUSIONS: Overall, these novel and unique cellular systems represent relevant experimental tools for a better understanding of the biology of these neoplasms and, as an extension, to MM from other sites.

Arsenic may be a carcinogenic determinant of a subset of gallbladder cancer: A pilot study.

Gallbladder cancer (GBC) is one of the deadliest malignancy and treatment options are deplorably limited. Better strategies of prevention are urgently needed but knowledge on risk factors remains scarce. Recent data suggested that arsenic (As) may be involved in GBC carcinogenesis but the question remains debated. To date, there are no data on As measurement in GBC samples. This pilot study aimed to measure As concentrations in tissue samples from patients with GBC compared to non-cancerous gallbladder (NCGB). Included patients underwent cholecystectomy at Hospital Clinico Universidad de Chile, Santiago in Chile, a country with high As exposure, between 2001 and 2020. Tissue samples were preserved in formalin-fixed, paraffin-embedded blocks. Selected samples were retrieved, processed and submitted to inductively coupled plasma mass spectrometry (ICP-MS) to determine As concentrations. A total of 77 patients were included, including 35 GBC and 42 NCGB. The two groups were comparable, except for age (68 vs. 49 years, p < 0.001). Measured in 11 GBC and 38 NCGB, total As was detected in 5 GBC (14%) compared to 0 NCGB samples (p < 0.001). GBC group also showed higher median values of As compared to NCGB (p < 0.001). This pilot study provided a proof-of-concept to measure As concentrations in gallbladder samples and showed higher level of As in GBC samples compared to NCGB, paving the way for future studies aiming to investigate the impact of As on GBC, which may contribute to the prevention of this deadly disease.

Natural Language Processing to extract SNOMED-CT codes from pathological reports.

Objective: The use of standardized structured reports (SSR) and suitable terminologies like SNOMED-CT can enhance data retrieval and analysis, fostering large-scale studies and collaboration. However, the still large prevalence of narrative reports in our laboratories warrants alternative and automated labeling approaches. In this project, natural language processing (NLP) methods were used to associate SNOMED-CT codes to structured and unstructured reports from an Italian Digital Pathology Department. Methods: Two NLP-based automatic coding systems (support vector machine, SVM, and long-short term memory, LSTM) were trained and applied to a series of narrative reports. Results: The 1163 cases were tested with both algorithms, showing good performances in terms of accuracy, precision, recall, and F1 score, with SVM showing slightly better performances as compared to LSTM (0.84, 0.87, 0.83, 0.82 vs 0.83, 0.85, 0.83, 0.82, respectively). The integration of an explainability allowed identification of terms and groups of words of importance, enabling fine-tuning, balancing semantic meaning and model performance. Conclusions: AI tools allow the automatic SNOMED-CT labeling of the pathology archives, providing a retrospective fix to the large lack of organization of narrative reports.

Gluten Induces Subtle Histological Changes in Duodenal Mucosa of Patients with Non-Coeliac Gluten Sensitivity: A Multicentre Study.

Background: Histological changes induced by gluten in the duodenal mucosa of patients with non-coeliac gluten sensitivity (NCGS) are poorly defined. Objectives: To evaluate the structural and inflammatory features of NCGS compared to controls and coeliac disease (CeD) with milder enteropathy (Marsh I-II). Methods: Well-oriented biopsies of 262 control cases with normal gastroscopy and histologic findings, 261 CeD, and 175 NCGS biopsies from 9 contributing countries were examined. Villus height (VH, in µm), crypt depth (CrD, in µm), villus-to-crypt ratios (VCR), IELs (intraepithelial lymphocytes/100 enterocytes), and other relevant histological, serologic, and demographic parameters were quantified. Results: The median VH in NCGS was significantly shorter (600, IQR: 400−705) than controls (900, IQR: 667−1112) (p < 0.001). NCGS patients with Marsh I-II had similar VH and VCR to CeD [465 µm (IQR: 390−620) vs. 427 µm (IQR: 348−569, p = 0·176)]. The VCR in NCGS with Marsh 0 was lower than controls (p < 0.001). The median IEL in NCGS with Marsh 0 was higher than controls (23.0 vs. 13.7, p < 0.001). To distinguish Marsh 0 NCGS from controls, an IEL cut-off of 14 showed 79% sensitivity and 55% specificity. IEL densities in Marsh I-II NCGS and CeD groups were similar. Conclusion: NCGS duodenal mucosa exhibits distinctive changes consistent with an intestinal response to luminal antigens, even at the Marsh 0 stage of villus architecture.

Reproducibility of the electronic chromoendoscopy PICaSSO score (Paddington International Virtual ChromoendoScopy ScOre) in ulcerative colitis using multiple endoscopic platforms: a prospective multicenter international study (with video).

BACKGROUND AND AIMS: Endoscopic and histologic remission (HR) are key therapeutic targets in the management of ulcerative colitis (UC). The aim of this study was to evaluate the reproducibility of the Paddington International virtual ChromoendoScopy ScOre (PICaSSO), a virtual chromoendoscopy score originally validated by use of the iSCAN platform, with the narrow-band imaging (NBI), linked-color imaging (LCI), and blue-laser imaging (BLI) platforms. METHODS: We evaluated endoscopic activity using the Mayo Endoscopic Score (MES), the Ulcerative Colitis Endoscopic Index of Severity (UCEIS), and PICaSSO in 159 UC patients (78 NBI and 81 BLI/LCI) who underwent colonoscopy in 2 tertiary referral centers. HR was defined by the Robarts Histopathology Index (RHI) and the Nancy Histologic Index (NHI). Receiver operating characteristic curves were plotted to evaluate endoscopic scores for the prediction of HR. Intraclass correlation coefficients (ICC) between endoscopists were evaluated. RESULTS: PICaSSO had an ICC of 0.825 when the NBI and BLI/LCI cohorts were combined, higher than MES and UCEIS. The correlation between PICaSSO and RHI and NHI was 0.83 and 0.79 in the NBI cohort and between 0.63 and 0.65 in LCI/BLI. In the NBI cohort, the accuracy of MES, UCEIS, and PICaSSO was 0.936, 0.897, and 0.808 for HR measured by RHI and 0.897, 0.885, and 0.821 by NHI, respectively. In the BLI/LCI cohort, the accuracy of MES, UCEIS, LCI PICaSSO and BLI PICaSSO was 0.765, 0.778, 0.827, and 0.79 to predict HR with RHI and NHI, respectively. CONCLUSIONS: The PICaSSO score can be consistently and accurately reproduced with NBI and LCI/BLI and therefore can be applied to all virtual electronic chromoendoscopy platforms.

Single-Shot Local Injection of Microfragmented Fat Tissue Loaded with Paclitaxel Induces Potent Growth Inhibition of Hepatocellular Carcinoma in Nude Mice.

Hepatocellular carcinoma (HCC) is poorly beneficiated by intravenous chemotherapy due to inadequate availability of drugs at the tumor site. We previously demonstrated that human micro-fragmented adipose tissue (MFAT) and its devitalized counterpart (DMFAT) could be effective natural scaffolds to deliver Paclitaxel (PTX) to tumors in both in vitro and in vivo tests, affecting cancer growth relapse. Here we tested the efficacy of DMFAT-PTX in a well-established HCC in nude mice. MFAT-PTX and DMFAT-PTX preparations were tested for anti-cancer activity in 2D and 3D assays using Hep-3B tumor cells. The efficacy of DMFAT-PTX was evaluated after a single-shot subcutaneous injection near a Hep-3B growing tumor by assessing tumor volumes, apoptosis rate, and drug pharmacokinetics in an in vivo model. Potent antiproliferative activity was seen in both in vitro 2D and 3D tests. Mice treated with DMFAT-PTX (10 mg/kg) produced potent Hep-3B growth inhibition with 33% complete tumor regressions. All treated animals experienced tumor ulceration at the site of DMFAT-PTX injection, which healed spontaneously. Lowering the drug concentration (5 mg/kg) prevented the formation of ulcers, maintaining statistically significant efficacy. Histology revealed a higher number of apoptotic cancer cells intratumorally, suggesting prolonged presence of PTX that was confirmed by the pharmacokinetic analysis. DMFAT may be a potent and valid new tool for local chemotherapy of HCC in an advanced stage of progression, also suggesting potential effectiveness in other human primary inoperable cancers.

Histopathology of IBD Colitis. A practical approach from the pathologists of the Italian Group for the study of the gastrointestinal tract (GIPAD).

Inflammatory bowel diseases (IBDs) are lifelong disorders in which an interaction between genetic and environmental factors is involved. IBDs include two entities: Crohn's disease (CD) and ulcerative colitis (UC); these can be adequately diagnosed and distinguished with a correct methodological approach based on communicating exhaustive clinical, endoscopic and laboratory information to the pathologist and performing adequate bioptic sampling and precise morphological signs including crypt architecture, distribution of inflammation and granulomas, when present. IBD needs to be distinguished from non-IBD colitis, mostly at its onset. Moreover, IBDs are associated with an increased risk of developing colorectal adenocarcinoma. In daily pathological practice, correct diagnosis of IBD and its subclassification as well as a correct detection of dysplasia is imperative to establish the best therapeutic approach.

Histopathology of Non-IBD Colitis. A practical approach from the Italian Group for the study of the gastrointestinal tract (GIPAD).

Non-IBD colitides (NIBDC) are intestinal diseases clinically and endoscopically overlapping with Inflammatory Bowel Diseases (IBD), sometimes with a similar histological picture. NIBDC include entities such as infectious colitis, ischemic colitis, pseudomembranous colitis, eosinophilic colitis, autoimmune enterocolitis, segmental colitis associated with diverticulosis, drug-induced colitis, radiation-induced colitis, diversion colitis, and microscopic colitis, this last including two entities: collagenous and lymphocytic colitis. The knowledge of the most useful histological features and the main clinical data for each entity is mandatory in daily clinical practice, for correct pathological diagnosis and clinical management.

Histopathology of non-IBD colitis practical recommendations from pathologists of IG-IBD Group.

Pathologists are often called upon to diagnose colitides that differ from the two main forms of inflammatory bowel disease (IBD). These non-IBD colitides include infectious colitis, microscopic colitis, ischemic colitis, eosinophilic colitis, autoimmune enterocolitis, segmental colitis associated with diverticulosis, drug-induced colitis, radiation colitis and diversion colitis. The diagnosis of these different disease entities relies on the histopathological examination of endoscopic biopsies of the gastrointestinal tract. This paper reviews the main histomorphological characteristics of the various Non-IBD colitides.

Microscopic imaging of Inflammatory Bowel Disease (IBD) and Non-IBD Colitis on digital slides: The Italian Group-IBD Pathologists experience.

BACKGROUND: The aim of the study is to report the experience of the pathologists of the Italian Group for the Study of Inflammatory Bowel Disease (IBD) (group formed by pathologists with various experience) on the morphological assessment of digital slides pertaining to IBD and Non-IBD colitis underlining the necessity to implement this tool in daily routine and its utility to share opinions on difficult cases. MATERIALS AND METHODS: Forty-eight histological slides stained with haematoxylin and eosin obtained from ileo-colorectal endoscopic biopsies were digitized using Menarini D-Sight 2.0 system, uploaded onto a website platform and shared among 40 pathologists participating in the study. Information regarding the site of biopsy was disclosed; clinical data were blinded. Each participant was committed to write a comment on microscopic features purposing diagnostic opinion. One month after the last uploaded case, a form was sent to each participant to evaluate the personal experience on digital slide sharing. RESULTS: Sixteen pathologists out of 40 (40%) had consistently accessed to the site,9/40 (22%) commented on all slides, a diagnostic opinion was rendered in 8 slides. Most common critical issues were: A) poor internet connection resulting in ineffective evaluation of the digital slides, B) time-consuming cases raising difficult diagnostic interpretation, C) lack of clinical history. Overall, 24 participants (60%) found the forum valuable for practical training and educational purposes. CONCLUSIONS: Sharing scanned slides circulating within a dedicated forum is an effective educational tool in both IBDs and Non-IBDs colitis. Although our results demonstrated a substantial compliance of the participants, their limited participation was an objective shortcoming. Hence, further efforts are needed to encourage this potentially rewarding practice among the pathologist community.

hERG1 and HIF-2α Behave as Biomarkers of Positive Response to Bevacizumab in Metastatic Colorectal Cancer Patients.

BACKGROUND: In search of novel biomarkers of response to bevacizumab in metastatic colorectal cancer (mCRC), we analyzed the expression and prognostic role of several proteins related to angiogenesis. METHODS: A retrospective, multicenter study on 80 surgical samples from mCRC patients treated in first line with bevacizumab plus chemotherapy was accomplished. The following proteins were analyzed by immunohistochemistry: hERG1 potassium channel, ß1-integrin, pAKT, NFkB, HIF-1α, HIF-2α, p53, VEGF-A, GLUT-1, and CA-IX. Data were analyzed in conjunction with the clinicopathological characteristics of the patients, KRAS status, response to bevacizumab, and follow-up. RESULTS: (1) All the proteins were expressed in the samples, with statistically significant associations between HIF-1α and gender, HIF-2α and left colon, hERG1 and VEGF-A, ß1-integrin and HIF-2α, GLUT-1 and both HIF-1α and HIF-2α, and CA-IX and VEGF-A. (2) At the univariate analysis, positivity for hERG1, VEGF-A, and the active form of HIF-2α (aHIF-2α), and the G3 histological grade showed a positive impact on progression-free survival (PFS). (3) hERG1 and aHIF-2α maintained their positive impact on PFS at the multivariate analysis. (4) hERG1 behaved as a protective factor for PFS independently on KRAS status. CONCLUSIONS: hERG1 and aHIF-2α might help to identify patients who would benefit from bevacizumab treatment.

Histopathology of inflammatory bowel disease - Position statement of the Pathologists of the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD) and Italian Group of Gastrointestinal Pathologists (GIPAD-SIAPEC).

Diagnosis of the inflammatory bowel diseases ulcerative colitis (UC) and Crohn's disease (CD) relies mainly on the histopathological examination of endoscopic biopsies of the gastrointestinal tract. To facilitate the accurate diagnosis of these two conditions, this paper addresses key issues on the: (A) gastrointestinal biopsy procedure, (B) histomorphological characteristics of UC and CD, and (C) diagnosis of dysplasia. The 13 statements presented here represent the consensus of two groups of Italian pathologists (IG-IBD and GIPAD).

Long Non-Coding RNA GAS5 and Intestinal MMP2 and MMP9 Expression: A Translational Study in Pediatric Patients with IBD.

BACKGROUND: The long non-coding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) seems to be involved in the regulation of mediators of tissue injury, in particular matrix metalloproteinases (MMPs), implicated in the pathogenesis of inflammatory bowel disease (IBD). We investigated the role of GAS5 in regulating MMP2 and MMP9 expression in pediatric patients with IBD and in vitro. METHODS: In total, 25 IBD patients were enrolled: For each patient paired inflamed and non-inflamed biopsies were collected. RNA was extracted and GAS5, MMP2, and MMP9 were quantified by TaqMan assay. The expression of GAS5 and MMPs was also determined in the human monocytic THP1 cells differentiated into macrophages and stimulated with lipopolysaccharide (LPS). The function of GAS5 was assessed by overexpressing the lncRNA and evaluating the MMPs levels. RESULTS: Real-time PCR results demonstrated a downregulation of GAS5 and an upregulation of both MMPs in inflamed tissues. In vitro data confirmed the trend observed in patients for the three genes: The stimulation with LPS promoted a downregulation of GAS5 while an increase of MMPs was observed. Overexpression experiments showed that higher levels of GAS5 lead to a decrease of both enzymes. CONCLUSION: These results provide new information about the role of GAS5 in IBD: The lncRNA could mediate tissue damage by modulating the expression of MMPs.

Long-Lasting Anti-Inflammatory Activity of Human Microfragmented Adipose Tissue.

Over the last few years, human microfragmented adipose tissue (MFAT), containing significant levels of mesenchymal stromal cells (MSCs) and obtained from fat lipoaspirate (LP) through a minimal manipulation in a closed system device, has been successfully used in aesthetic medicine as well as in orthopedic and general surgery. Interestingly, in orthopedic diseases, this ready-to-use adipose tissue cell derivative seems to have a prolonged time efficacy even upon a single shot injection into osteoarthritic tissues. Here, we investigated the long-term survival and content of MSCs as well the anti-inflammatory activity of LP and its derived MFAT in vitro, with the aim to better understand a possible in vivo mechanism of action. MFAT and LP specimens from 17 human donors were investigated side by side. During a long-term culture in serum-free medium, we found that the total cell number as well the MSC content in MFAT decreased more slowly if compared to those from LP specimens. The analysis of cytokines and growth factors secreted into the conditioned medium (CM) was similar in MFAT and LP during the first week of culture, but the total amount of cytokines secreted by LP decreased much more rapidly than those produced by MFAT during prolonged culture (up to 28 days). Similarly, the addition of MFAT-CM recovered at early (3-7 days) and late stage (14-28 days) of culture strongly inhibited inflammatory function of U937 monocyte cell line, whereas the anti-inflammatory activity of LP-CM was drastically reduced after only 7 days of culture. We conclude that MFAT is an effective preparation with a long-lasting anti-inflammatory activity probably mediated by a long-term survival of their MSC content that releases a combination of cytokines that affect several mechanisms involved in inflammation processes.

Localization of TNF alpha in ileocolonic biopsies of patients with inflammatory bowel disease.

BACKGROUND: Although antitumor necrosis factor alfa (TNFα) agents are widely used to treat patients with inflammatory bowel diseases (IBD) - both Crohn's disease (CD) and ulcerative colitis (UC) - there is still some uncertainty in the cell type expressing TNFα in human ileo-colonic segments. AIMS: We investigated the immunohistochemical (IHC) expression of TNFα in the ileo-colonic segments of patients with both active CD and UC, to establish its anatomic and cellular localization in the inflamed sites. Our aim was to identify patients potentially resistant to anti TNFα agents. PATIENTS AND METHODS: Ileo-colonic slides of complete histological mapping of patients with CD and UC before any treatment was started were obtained, and serial sections assessed for TNFα expression, together with IHC markers for lymphocytes, macrophages, and plasma cells. RESULTS: TNFα was expressed in almost all inflamed segments of IBD patients, albeit with different strength, and was present, in addition to lymphocytes and, to a lesser extent, to macrophages, in plasma cells, where it had a strong positivity, as also demonstrated by colocalization of specific IHC staining. The expression of TNFα was mostly focal in CD patients and more diffuse in UC patients, likely due to the different patterns of inflammation (transmural and mucosal) of the two entities. CONCLUSIONS: In IBD, TNFα is strongly expressed also in plasma cells, and it is easily evidenced by conventional IHC techniques. It remains to be established whether this observation might be useful in future to establish in routine biopsy samples whether patients may be responsive to treatments toward this cytokine.

Colonic hypereosinophilia in ulcerative colitis may help to predict the failure of steroid therapy.

BACKGROUND: Although glucocorticosteroids (GS) and mesalazine are effective and widely employed to treat moderate-to-severe ulcerative colitis (UC), information regarding the factors responsible for response to such therapy is still scarce. One of these factors is thought to be an increased number of mucosal eosinophils. The aim of our study was to determine whether the presence of hypereosinophilia in colonic mucosa of UC patients might influence the short-term response to l treatment with GS and mesasalazine. METHODS: Clinical, endoscopic, and pathologic data from patients with a recent diagnosis of moderate UC, who had not undergone treatment, were obtained, and the short-term outcome after 1 month of conventional first-line treatment (mesalazine plus GS) was evaluated. RESULTS: There were 53 patients with a median age of 37 years (95% CI 30-47).Overall, at the end of treatment period 16 (30%) patients responded, whereas a response was not observed in the other 37 (70%) patients. Interestingly, all patients of this latter group had colonic mucosal hypereosinophilia. No significant differences were found between the two groups concerning sex and age at diagnosis, but hypereosinophilia was inversely correlated with the duration of the disease (p = 0.054), and significantly correlated to the localization of UC (p = 0.0023). In addition, The Mayo score was significantly higher in patients with hypereosinophilia (median 8; 95% CI 8-9;) when compared to patients without hypereosinophilia (median 7; 95% CI 7-7, p < 0.0001) including the Mayo endoscopic subscore (median 3; 95% CI 2-3 vs median 2; 95% CI 2-2, respectively; p = 0.007). CONCLUSIONS: The presence of colonic mucosal hypereosinophilia may be useful to predict the short-term outcome to conventional first-line therapy in treatment-naïve UC patients. It remains to be seen whether this might be important in modifying the first-line therapy in this subgroup of patients.

7-Hydroxymatairesinol improves body weight, fat and sugar metabolism in C57BJ/6 mice on a high-fat diet.

7-Hydroxymatairesinol (7-HMR) is a plant lignan abundant in various concentrations in plant foods. The objective of this study was to test HMRLignan™, a purified form of 7-HMR, and the corresponding Picea abies extract (total extract P. abies; TEP) as dietary supplements on a background of a high-fat diet (HFD)-induced metabolic syndrome in mice and in the 3T3-L1 adipogenesis model. Mice, 3 weeks old, were fed a HFD for 60 d. Subgroups were treated with 3 mg/kg body weight 7-HMR (HMRLignan™) or 10 mg/kg body weight TEP by oral administration. 7-HMR and TEP limited the increase in body weight (-11 and -13 %) and fat mass (-11 and -18 %) in the HFD-fed mice. Epididymal adipocytes were 19 and -12 % smaller and the liver was less steatotic (-62 and -65 %). Serum lipids decreased in TEP-treated mice (-11 % cholesterol, -23 % LDL and -15 % TAG) and sugar metabolism was ameliorated by both lignan preparations, as shown by a more than 70 % decrease in insulin secretion and insulin resistance. The expression of several metabolic genes was modulated by the HFD with an effect that was reversed by lignan. In 3T3-L1 cells, the 7-HMR metabolites enterolactone (ENL) and enterodiol (END) showed a 40 % inhibition of cell differentiation accompanied by the inhibited expression of the adipogenic genes PPARγ, C/EBPα and aP2. Furthermore, END and ENL caused a 10 % reduction in TAG uptake in HEPA 1-6 hepatoma cells. In conclusion, 7-HMR and TEP reduce metabolic imbalances typical of the metabolic syndrome and obesity in male mice, whereas their metabolites inhibit adipogenesis and lipid uptake in vitro.